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Xie Y, Long X, Kim Y, Harris LJ, Nitin N. Survival of Salmonella enterica and Enterococcus faecium on Abiotic Surfaces During Storage at Low Relative Humidity. J Food Prot 2024; 87:100292. [PMID: 38718984 DOI: 10.1016/j.jfp.2024.100292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/26/2024] [Accepted: 04/30/2024] [Indexed: 05/23/2024]
Abstract
Currently, there is limited knowledge on the survival of bacteria on surfaces during postharvest handling of dry products such as onions. Extended survival of microorganisms, coupled with a lack of established and regular, validated cleaning or sanitation methods could enable cross-contamination of these products. The aim of the study was to evaluate the survival of a potential surrogate, Enterococcus faecium, and Salmonella enterica on typical onion handling surfaces, polyurethane (PU), and stainless steel (SS), under low relative humidity. The influence of onion extract on the survival of E. faecium and Salmonella on PU and SS was also investigated. Rifampin-resistant E. faecium NRRL B-2354 and a five-strain cocktail of Salmonella suspended in 0.1% peptone or onion extract were separately inoculated onto PU and SS coupons (2 × 2 cm), at high, moderate, or low (7, 5, or 3 log CFU/cm2) levels. The inoculated surfaces were stored at ∼34% relative humidity and 21°C for up to 84 days. Triplicate samples were enumerated at regular intervals in replicate trials. Samples were enriched when populations fell below the limit of detection by plating (0.48 log CFU/cm2). Scanning electron microscopy was used to observe the cell distribution on the coupons. Reductions of E. faecium of less than ∼2 log were observed on PU and SS over 12 weeks at all inoculum levels and with both inoculum carriers. In 0.1% peptone, Salmonella populations declined by 2 to 3 log over 12 weeks at the high and moderate inoculum levels; at the low inoculum level, Salmonella could not be recovered by enrichment at 84 days. Survival of E. faecium and Salmonella was significantly (P < 0.05) enhanced over 84 days of storage when suspended in onion extract, where cells were covered by a layer of onion extract. E. faecium might have utility as a conservative surrogate for Salmonella when evaluating microbial survival on dry food-contact surfaces.
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Affiliation(s)
- Yucen Xie
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - Xiaonuo Long
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - Yoonbin Kim
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - Linda J Harris
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA; Western Center for Food Safety, University of California, Davis, CA 95616, USA.
| | - Nitin Nitin
- Department of Food Science and Technology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA; Department of Agricultural and Biological Engineering, University of California, Davis, CA 95616, USA.
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Mkangara M. Prevention and Control of Human Salmonella enterica Infections: An Implication in Food Safety. INTERNATIONAL JOURNAL OF FOOD SCIENCE 2023; 2023:8899596. [PMID: 37727836 PMCID: PMC10506869 DOI: 10.1155/2023/8899596] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 08/19/2023] [Accepted: 08/26/2023] [Indexed: 09/21/2023]
Abstract
Salmonella is a foodborne zoonotic pathogen causing diarrhoeal disease to humans after consuming contaminated water, animal, and plant products. The bacterium is the third leading cause of human death among diarrhoeal diseases worldwide. Therefore, human salmonellosis is of public health concern demanding integrated interventions against the causative agent, Salmonella enterica. The prevention of salmonellosis in humans is intricate due to several factors, including an immune-stable individual infected with S. enterica continuing to shed live bacteria without showing any clinical signs. Similarly, the asymptomatic Salmonella animals are the source of salmonellosis in humans after consuming contaminated food products. Furthermore, the contaminated products of plant and animal origin are a menace in food industries due to Salmonella biofilms, which enhance colonization, persistence, and survival of bacteria on equipment. The contaminated food products resulting from bacteria on equipment offset the economic competition of food industries and partner institutions in international business. The most worldwide prevalent broad-range Salmonella serovars affecting humans are Salmonella Typhimurium and Salmonella Enteritidis, and poultry products, among others, are the primary source of infection. The broader range of Salmonella serovars creates concern over multiple strategies for preventing and controlling Salmonella contamination in foods to enhance food safety for humans. Among the strategies for preventing and controlling Salmonella spread in animal and plant products include biosecurity measures, isolation and quarantine, epidemiological surveillance, farming systems, herbs and spices, and vaccination. Other measures are the application of phages, probiotics, prebiotics, and nanoparticles reduced and capped with antimicrobial agents. Therefore, Salmonella-free products, such as beef, pork, poultry meat, eggs, milk, and plant foods, such as vegetables and fruits, will prevent humans from Salmonella infection. This review explains Salmonella infection in humans caused by consuming contaminated foods and the interventions against Salmonella contamination in foods to enhance food safety and quality for humans.
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Affiliation(s)
- Mwanaisha Mkangara
- Department of Science and Laboratory Technology, Dar es Salaam Institute of Technology, P.O. Box 2958, Dar es Salaam, Tanzania
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3
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Xu S, Chen H. The influence of almond's water activity and storage temperature on Salmonella survival and thermal resistance. Food Microbiol 2023; 113:104269. [PMID: 37098429 DOI: 10.1016/j.fm.2023.104269] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/21/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023]
Abstract
This study investigated the effects of inoculation method, water activity (aw), packaging method, and storage temperature and duration on the survival of Salmonella on almonds as well as their resistance to subsequent thermal treatments. Whole almond kernels were inoculated with a broth-based or agar-based growth Salmonella cocktail and conditioned to aw of 0.52, 0.43 or 0.27. Inoculated almonds with aw of 0.43 were treated with a previously validated treatment (4 h of dry heat at 73 °C) to determine the potential differences in heat resistance resulted from the two inoculation methods. The inoculation method did not significantly (P > 0.05) impact the thermal resistance of Salmonella. Inoculated almonds at aw of 0.52 and 0.27 were either vacuum packaged in moisture-impermeable mylar bags or non-vacuum packaged in moisture-permeable polyethylene bags before stored at 35, 22, 4, or -18 °C for up to 28 days. At selected storage intervals, almonds were measured for aw, analyzed for Salmonella population level, and subjected to dry heat treatment at 75 °C. Over the month-long storage of almonds, Salmonella populations remained almost unchanged (<0.2 log CFU/g) at 4 °C and -18 °C and declined slightly (<0.8 log CFU/g) at 22 °C and more substantially (1.6-2.0 log CFU/g) at 35 °C regardless of the inoculation method, packaging method, and almond aw. When stored at 35 °C, almonds with initial aw of 0.52 had significantly higher (P < 0.05) Salmonella reductions than those with initial aw of 0.27. Prior storage of almonds vacuum packaged in mylar bags at temperatures between -18 °C and 35 °C for 28 days affected their aw levels but did not significantly (P > 0.05) affect the subsequent thermal resistance of Salmonella at 75 °C regardless of almond aw and storage duration. Salmonella on almonds with higher aw was more sensitive to heat treatment than those with lower aw. To achieve >5 log CFU/g reductions of Salmonella, a dry heat treatment at 75 °C for 4 and 6 h was needed for almonds with initial aw of 0.52 and 0.27, respectively. When applying the dry heating technology for almond decontamination, the processing time needs to be determined based on initial aw of almonds regardless of storage condition or age of almonds within the current design frame.
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Zwe YH, Li D. Pathogenic and transmissional potentials of a Chromobacterium haemolyticum isolate from a hydroponic farm. J Appl Microbiol 2023; 134:lxad149. [PMID: 37442627 DOI: 10.1093/jambio/lxad149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/26/2023] [Accepted: 07/12/2023] [Indexed: 07/15/2023]
Abstract
AIMS This study aims to investigate the in vitro pathogenicity of Chromobacterium haemolyticum strain WI5 toward the intestinal tract, its resistance to water treatments, and its potential for foodborne transmission through leafy greens produced in hydroponic systems. METHODS AND RESULTS C. haemolyticum WI5 caused cytopathic effects in human colon cells HCT116 and exhibited an 8.2-fold higher cell attachment compared to Salmonella serotype Typhimurium. It showed comparable resistance to sodium hypochlorite (NaOCl) and ultraviolet (UV) treatments as Escherichia coli O157: H7 and Pseudomonas aeruginosa but was more susceptible to desiccation. On lettuce, C. haemolyticum WI5 failed to persist, with counts decreasing below the detection limit (≥4 log reductions) after 3 and 2 days at 4 and 25°C, respectively. CONCLUSIONS C. haemolyticum WI5 demonstrated considerable virulence features and high in vitro pathogenicity toward the intestinal tract. NaOCl and UV treatments were effective in disinfecting C. haemolyticum in water. Due to its high susceptibility to desiccation and poor survivability on lettuce, the foodborne transmission potential of C. haemolyticum is considered limited.
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Affiliation(s)
- Ye Htut Zwe
- Department of Food Science and Technology, National University of Singapore, Singapore 117543
| | - Dan Li
- Department of Food Science and Technology, National University of Singapore, Singapore 117543
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5
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Fay ML, Salazar JK, Zhang X, Zhou X, Stewart D. Long-Term Survival of Listeria monocytogenes in Nut, Seed, and Legume Butters. J Food Prot 2023; 86:100094. [PMID: 37086973 DOI: 10.1016/j.jfp.2023.100094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/12/2023] [Accepted: 04/17/2023] [Indexed: 04/24/2023]
Abstract
Nut, seed, and legume butters have become increasingly popular with consumers. Listeria monocytogenes contamination of a variety of butters has resulted in several recalls, although no known outbreaks have been identified. L. monocytogenes has been shown to survive on a variety of seeds for up to 6 months, legumes and nuts for over 12 months, and in peanut butter and peanut-chocolate spreads for 21 to 60 weeks depending on formulation; however, long-term survival in other butters has not yet been characterized. In this study, the survival of L. monocytogenes in various nut, seed, legume, and chocolate-containing butters (n=10) based on inoculation level, storage temperature, and the pH, aw, and nutrient contents of the butters, was examined. First, butters were inoculated with L. monocytogenes at 4 log CFU/g and stored at either 5 or 25°C with enumeration and/or enrichment at intervals over 12 months. L. monocytogenes survived in all butters examined with no significant change in population after storage at 5°C, whereas the population was reduced to <1.70 log CFU/g in as little as 3 months at 25°C; the only exception was for sunflower butter, where L. monocytogenes decreased approximately 1 log CFU/g. Subsequently, all butters were inoculated at 1 log CFU/g and stored at 25°C for 6 months with enrichment during storage. L. monocytogenes was detected in all butters, except pecan butter, after 6-month storage. Butters containing chocolate did not inhibit L. monocytogenes survival, regardless of the inoculation level. Results indicate there may be association between high fat and carbohydrate level and survivability of L. monocytogenes in various types of butters. This work highlights the need to mitigate the potential for cross-contamination of L. monocytogenes into nut, seed, and legume butters due to the potential for long-term survival. Running title: Listeria survival in butters.
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Affiliation(s)
- Megan L Fay
- Division of Food Processing Science and Technology, U. S. Food and Drug Administration, Bedford Park, IL, USA
| | - Joelle K Salazar
- Division of Food Processing Science and Technology, U. S. Food and Drug Administration, Bedford Park, IL, USA.
| | - Xinyuan Zhang
- Illinois Institute of Technology, Institute for Food Safety and Health, Bedford Park, IL, USA
| | - Xinyi Zhou
- Illinois Institute of Technology, Institute for Food Safety and Health, Bedford Park, IL, USA
| | - Diana Stewart
- Division of Food Processing Science and Technology, U. S. Food and Drug Administration, Bedford Park, IL, USA
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6
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Ahmad NH, Hildebrandt IM, Pickens SR, Vasquez S, Jin Y, Liu S, Halik LA, Tsai HC, Lau SK, D'Souza RC, Kumar S, Subbiah J, Thippareddi H, Zhu MJ, Tang J, Anderson NM, Grasso-Kelley EM, Ryser ET, Marks BP. Interlaboratory Evaluation of Enterococcus faecium NRRL B-2354 as a Salmonella Surrogate for Validating Thermal Treatment of Multiple Low-Moisture Foods. J Food Prot 2022; 85:1538-1552. [PMID: 35723555 DOI: 10.4315/jfp-22-054] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 06/16/2022] [Indexed: 11/11/2022]
Abstract
ABSTRACT This multi-institutional study assessed the efficacy of Enterococcus faecium NRRL B-2354 as a nonpathogenic Salmonella surrogate for thermal processing of nonfat dry milk powder, peanut butter, almond meal, wheat flour, ground black pepper, and date paste. Each product was analyzed by two laboratories (five independent laboratories total), with the lead laboratory inoculating (E. faecium or a five-strain Salmonella enterica serovar cocktail of Agona, Reading, Tennessee, Mbandaka, and Montevideo) and equilibrating the product to the target water activity before shipping. Both laboratories subjected samples to three isothermal treatments (between 65 and 100°C). A log-linear and Bigelow model was fit to survivor data via one-step regression. On the basis of D80°C values estimated from the combined model, E. faecium was more thermally resistant (P < 0.05) than Salmonella in nonfat dry milk powder (DEf-80°C, 100.2 ± 5.8 min; DSal-80°C, 28.9 ± 1.0 min), peanut butter (DEf-80°C, 133.5 ± 3.1 min; DSal-80°C, 57.6 ± 1.5 min), almond meal (DEf-80°C, 34.2 ± 0.4 min; DSal-80°C, 26.1 ± 0.2 min), ground black pepper (DEf-80°C, 3.2 ± 0.8 min; DSal-80°C, 1.5 ± 0.1 min), and date paste (DEf-80°C, 1.5 ± 0.0 min; DSal-80°C, 0.5 ± 0.0 min). Although the combined laboratory D80°C for E. faecium was lower (P < 0.05) than for Salmonella in wheat flour (DEf-80°C, 9.4 ± 0.1 min; DSal-80°C, 10.1 ± 0.2 min), the difference was ∼7%. The zT values for Salmonella in all products and for E. faecium in milk powder, almond meal, and date paste were not different (P > 0.05) between laboratories. Therefore, this study demonstrated the impact of standardized methodologies on repeatability of microbial inactivation results. Overall, E. faecium NRRL B-2354 was more thermally resistant than Salmonella, which provides support for utilizing E. faecium as a surrogate for validating thermal processing of multiple low-moisture products. However, product composition should always be considered before making that decision. HIGHLIGHTS
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Affiliation(s)
- Nurul Hawa Ahmad
- Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824
| | - Ian M Hildebrandt
- Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, Michigan 48824.,U.S. Food Drug Administration, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Shannon R Pickens
- U.S. Food Drug Administration, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Sabrina Vasquez
- Department of Food Science and Technology, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Yuqiao Jin
- Department of Biological Systems Engineering, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Shuxiang Liu
- Department of Biological Systems Engineering, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Lindsay A Halik
- Illinois Institute of Technology, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Hsieh-Chin Tsai
- School of Food Science, Washington State University, Pullman, Washington 99164
| | - Soon Kiat Lau
- Department of Food Science and Technology, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501.,Department of Biological System Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588
| | - Roshan C D'Souza
- Department of Poultry Science, University of Georgia, Athens, Georgia 30602, USA
| | - Sanjay Kumar
- Department of Poultry Science, University of Georgia, Athens, Georgia 30602, USA
| | - Jeyamkondan Subbiah
- Department of Food Science and Technology, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501.,Department of Biological System Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska 68588
| | | | - Mei-Jun Zhu
- School of Food Science, Washington State University, Pullman, Washington 99164
| | - Juming Tang
- Department of Biological Systems Engineering, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Nathan M Anderson
- U.S. Food Drug Administration, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Elizabeth M Grasso-Kelley
- U.S. Food Drug Administration, Institute of Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Elliot T Ryser
- Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824
| | - Bradley P Marks
- Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, Michigan 48824
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Thermal Death Kinetics of Three Representative Salmonella enterica Strains in Toasted Oats Cereal. Microorganisms 2022; 10:microorganisms10081570. [PMID: 36013988 PMCID: PMC9416204 DOI: 10.3390/microorganisms10081570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 08/01/2022] [Indexed: 11/16/2022] Open
Abstract
Several reports have indicated that the thermal tolerance of Salmonella at low-water activity increases significantly, but information on the impact of diverse food matrices is still scarce. The goal of this research was to determine the kinetic parameters (decimal reduction time, D; time required for the first decimal reduction, δ) of thermal resistance of Salmonella in a previously cooked low water activity food. Commercial toasted oats cereal (TOC) was used as the food model, with or without sucrose (25%) addition. TOC samples were inoculated with 108 CFU/mL of a single strain of one of three Salmonella serovars (Agona, Tennessee, Typhimurium). TOC samples were ground and equilibrated to aw values of 0.11, 0.33 and 0.53, respectively. Ground TOC was heated at temperatures between 65 °C and 105 °C and viable counts were determined over time (depending on the temperature for up to 6 h). Death kinetic parameters were determined using linear and Weibull regression models. More than 70% of Weibull’s adjusted regression coefficients (Radj2) and only 38% of the linear model’s Radj2 had values greater than 0.8. For all serovars, both D and δ values increased consistently at a 0.11 aw compared to 0.33 and 0.53. At 0.33 aw, the δ values for Typhimurium, Tennessee and Agona were 0.55, 1.01 and 2.87, respectively, at 85 °C, but these values increased to 65, 105 and 64 min, respectively, at 0.11 aw. At 100 °C, δ values were 0.9, 5.5 and 2.3 min, respectively, at 0.11 aw. The addition of sucrose resulted in a consistent reduction of eight out of nine δ values determined at 0.11 aw at 85, 95 and 100 °C, but this trend was not consistent at 0.33 and 0.53 aw. The Z values (increase of temperature required to decrease δ-value one log) were determined with modified δ values for a fixed β (a fitting parameter that describes the shape of the curve), and ranged between 8.9 °C and 13.4 °C; they were not influenced by aw, strain or sugar content. These findings indicated that in TOC, high thermal tolerance was consistent among serovars and thermal tolerance was inversely dependent on aw.
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8
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Thermal death kinetics of Salmonella Enteritidis PT30 in peanut butter as influenced by water activity. Food Res Int 2022; 157:111288. [DOI: 10.1016/j.foodres.2022.111288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 04/20/2022] [Accepted: 04/21/2022] [Indexed: 11/22/2022]
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9
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Xie Y, Zhang S, Sun S, Zhu MJ, Sablani S, Tang J. Survivability of Salmonella and Enterococcus faecium in chili, cinnamon and black pepper powders during storage and isothermal treatments. Food Control 2022. [DOI: 10.1016/j.foodcont.2022.108935] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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10
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Recent development in low-moisture foods: Microbial safety and thermal process. Food Res Int 2022; 155:111072. [DOI: 10.1016/j.foodres.2022.111072] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/22/2022] [Accepted: 02/24/2022] [Indexed: 11/17/2022]
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11
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Szpinak V, Ganz M, Yaron S. Factors affecting the thermal resistance of Salmonella Typhimurium in tahini. Food Res Int 2022; 155:111088. [DOI: 10.1016/j.foodres.2022.111088] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 01/16/2022] [Accepted: 02/28/2022] [Indexed: 11/25/2022]
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12
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Morasi RM, Rall VLM, Dantas STA, Alonso VPP, Silva NCC. Salmonella spp. in low water activity food: Occurrence, survival mechanisms, and thermoresistance. J Food Sci 2022; 87:2310-2323. [PMID: 35478321 DOI: 10.1111/1750-3841.16152] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 03/04/2022] [Accepted: 03/22/2022] [Indexed: 01/17/2023]
Abstract
The occurrence of disease outbreaks involving low-water-activity (aw ) foods has gained increased prominence due in part to the fact that reducing free water in these foods is normally a measure that controls the growth and multiplication of pathogenic microorganisms. Salmonella, one of the main bacteria involved in these outbreaks, represents a major public health problem worldwide and in Brazil, which highlights the importance of good manufacturing and handling practices for food quality. The virulence of this pathogen, associated with its high ability to persist in the environment, makes Salmonella one of the main challenges for the food industry. The objectives of this article are to present the general characteristics, virulence, thermoresistance, control, and relevance of Salmonella in foodborne diseases, and describe the so-called low-water-activity foods and the salmonellosis outbreaks involving them.
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Affiliation(s)
- Rafaela Martins Morasi
- Department of Food Sciences And Nutrition, Faculty of Food Engineering, State University of Campinas (UNICAMP), Monteiro Lobato Street, 80, Campinas, São Paulo, Brazil
| | - Vera Lúcia Mores Rall
- Sector of Microbiology and Immunology, Department of Chemical and Biological Sciences, Institute of Biosciences of Botucatu, São Paulo State University (UNESP), Botucatu, Brazil
| | - Stéfani Thais Alves Dantas
- Sector of Microbiology and Immunology, Department of Chemical and Biological Sciences, Institute of Biosciences of Botucatu, São Paulo State University (UNESP), Botucatu, Brazil
| | - Vanessa Pereira Perez Alonso
- Department of Food Sciences And Nutrition, Faculty of Food Engineering, State University of Campinas (UNICAMP), Monteiro Lobato Street, 80, Campinas, São Paulo, Brazil
| | - Nathália Cristina Cirone Silva
- Department of Food Sciences And Nutrition, Faculty of Food Engineering, State University of Campinas (UNICAMP), Monteiro Lobato Street, 80, Campinas, São Paulo, Brazil
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13
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Flock G, Richardson M, Pacitto-Reilly D, Anderson N, Chen F, Ahnrud G, Mendoza A, Senecal A. Survival of Salmonella enterica in Military Low-Moisture Food Products during Long-Term Storage at 4, 25, and 40°C. J Food Prot 2022; 85:544-552. [PMID: 34669966 DOI: 10.4315/jfp-21-321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 10/19/2021] [Indexed: 11/11/2022]
Abstract
ABSTRACT Salmonella enterica has been increasingly implicated in foodborne outbreaks involving low-moisture foods (LMF) during the recent decade. This study aimed to investigate the potential for persistence of S. enterica in a range of LMF during storage at three temperatures. LMF products, boil-in-bag eggs (freeze-dried product), chocolate protein drink, cran-raspberry First Strike bars, mocha dessert bar, and peanut butter, were inoculated with a five-strain cocktail of S. enterica and stored at 4, 25, or 40°C for 36 months. Salmonella populations remained above 7 log CFU/g in all products stored at 4°C and above 6 log CFU/g in products stored at 25°C, excluding the cran-raspberry First Strike bars. Storage at 40°C resulted in Salmonella populations above 5.5 log CFU/g in boil-in-bag eggs after 36 months and demonstrated survivability for 12 months or less in the other five products. Additionally, a mocha bar production temperature profile study identified rapid cooling of bars in which the temperatures reached would have no measurable impact on Salmonella populations. The results indicate the ability of Salmonella to survive in a variety of LMF category foods, even under adverse storage conditions and identifies how the food matrix may affect Salmonella survivability. The data indicate the importance of establishing food processing procedures that adequately mitigate the presence of Salmonella throughout food processing systems, while also increasing comprehensive understanding of Salmonella survivability mechanisms. HIGHLIGHTS
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Affiliation(s)
- Genevieve Flock
- Combat Capabilities Development Command Soldier Center, 10 General Greene Avenue, Natick, Massachusetts 01760, USA
| | - Michelle Richardson
- Combat Capabilities Development Command Soldier Center, 10 General Greene Avenue, Natick, Massachusetts 01760, USA
| | - Dominique Pacitto-Reilly
- Combat Capabilities Development Command Soldier Center, 10 General Greene Avenue, Natick, Massachusetts 01760, USA
| | - Nathan Anderson
- Illinois Institute of Technology, Institute for Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Fangyu Chen
- Binjiang Center, Binjiang Boulevard, Lujiazui, Pudong, Shanghai 200120, People's Republic of China
| | - Gianna Ahnrud
- Combat Capabilities Development Command Soldier Center, 10 General Greene Avenue, Natick, Massachusetts 01760, USA
| | - Alma Mendoza
- Combat Capabilities Development Command Soldier Center, 10 General Greene Avenue, Natick, Massachusetts 01760, USA
| | - Andre Senecal
- Combat Capabilities Development Command Soldier Center, 10 General Greene Avenue, Natick, Massachusetts 01760, USA
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14
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Suehr QJ, Liu X, Grasso-Kelley EM, Anderson NM. Predictive Microbial Modeling of Enterococcus faecium NRRL B-2354 Inactivation during Baking of a Multicomponent Low-Moisture Food. J Food Prot 2021; 84:1990-2001. [PMID: 34189582 DOI: 10.4315/jfp-21-036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 06/28/2021] [Indexed: 11/11/2022]
Abstract
ABSTRACT The use of baking ovens as a microbial kill step should be validated based on results of thermal inactivation models. Although traditional isothermal models may not be appropriate for these dynamic processes, they are being used by the food industry. Previous research indicates that the impact of additional process conditions, such as humidity, should be considered when validating thermal processes for the control of microbial hazards in low-moisture foods. In this study, the predictive performance of traditional and modified thermal inactivation kinetic models accounting for process humidity were assessed for predicting inactivation of Enterococcus faecium NRRL B-2354 in a multi-ingredient composite food during baking. Ingredients (milk powder, protein powder, peanut butter, and whole wheat flour) were individually inoculated to achieve ∼6 log CFU/g, equilibrated to a water activity of 0.25, and then mixed to form a cookie dough. An isothermal inactivation study was conducted for the dough to obtain traditional D- and z-values (n = 63). In a separate experiment, cookies were baked under four dynamic heating conditions: 135°C, high humidity; 135°C, low humidity; 150°C, high humidity; and 150°C, low humidity. Process humidity measurements; time-temperature profiles for the product core, surface, and bulk air; and microbial survivor ratios were collected for the four conditions at six residence times (n = 144). The traditional isothermal model had a high root mean square error (RMSE) of 856.51 log CFU/g, significantly overpredicting bacterial inactivation during the process. The modified model accounting for the dynamic time-temperature profile and process humidity data was a better predictor with an RMSE of 0.55 log CFU/g. These results indicate the importance of accounting for additional process parameters in baking inactivation models and that model performance can be improved by utilizing model parameters obtained directly from industrial-scale experimental data. HIGHLIGHTS
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Affiliation(s)
- Quincy J Suehr
- U.S. Food and Drug Administration, Illinois Institute of Technology, Institute for Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Xiyang Liu
- Department of Food Science and Nutrition, Illinois Institute of Technology, Institute for Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Elizabeth M Grasso-Kelley
- Department of Food Science and Nutrition, Illinois Institute of Technology, Institute for Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Nathan M Anderson
- U.S. Food and Drug Administration, Illinois Institute of Technology, Institute for Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
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15
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Thermal inactivation of Salmonella, Listeria monocytogenes and Enterococcus faecium NRRL B-2354 in desiccated shredded coconut. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.111851] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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16
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Desiccation and thermal resistance of Salmonella and Enterococcus faecium NRRL B-2354 in almond meal as impacted by water activity and storage temperature. Food Control 2021. [DOI: 10.1016/j.foodcont.2021.108037] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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17
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Xie T, Yuan X, Wen D, Shi H. Growth and thermal inactivation of
Listeria monocytogenes
and
Escherichia coli
O157:H7 in four kinds of traditionally non‐fermented soya bean products. Int J Food Sci Technol 2021. [DOI: 10.1111/ijfs.15031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Tianhui Xie
- College of Food Science Southwest University 1 Rd Tiansheng Beibei, Chongqing400715China
| | - Xue Yuan
- College of Food Science Southwest University 1 Rd Tiansheng Beibei, Chongqing400715China
| | - Dingyuan Wen
- College of Food Science Southwest University 1 Rd Tiansheng Beibei, Chongqing400715China
| | - Hui Shi
- College of Food Science Southwest University 1 Rd Tiansheng Beibei, Chongqing400715China
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18
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Dhowlaghar N, Zhu MJ. Control of Salmonella in low-moisture foods: Enterococcus faecium NRRL B-2354 as a surrogate for thermal and non-thermal validation. Crit Rev Food Sci Nutr 2021; 62:5886-5902. [PMID: 33798006 DOI: 10.1080/10408398.2021.1895055] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Salmonella has been implicated in multiple foodborne outbreaks and recalls associated with low water activity foods (LawF). To verify the effectiveness of a process against Salmonella in LawF, validation using a nonpathogenic surrogate strain is essential. Enterococcus faecium NRRL B-2354 strain has been used as a potential surrogate of Salmonella in different processing of LawF. However, the survival of Salmonella and E. faecium in LawF during food processing is a dynamic function of aw, food composition and structure, processing techniques, and other factors. This review assessed pertinent literature on the thermal and non-thermal inactivation of Salmonella and its presumable surrogate E. faecium in various LawF and provided an overview of its suitibility in different LawF. Overall, based on the D-values, survival/reduction, temperature/time to obtain 4 or 5-log reductions, most studies concluded that E. faecium is a suitable surrogate of Salmonella during LawF processing as its magnitude of resistance was slightly greater or equal (i.e., statistical similar) as compared to Salmonella. Studies also showed its unsuitability which either does not provide a proper margin of safety or being overly resistant and may compromise the quality and organoleptic properties of food. This review provides useful information and guidance for future validation studies of LawF.
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Affiliation(s)
- Nitin Dhowlaghar
- School of Food Science, Washington State University, Pullman, Washington, USA
| | - Mei-Jun Zhu
- School of Food Science, Washington State University, Pullman, Washington, USA
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19
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Yan R, Pinto G, Taylor-Roseman R, Cogan K, D'Alesandre G, Kovac J. Evaluation of the Thermal Inactivation of a Salmonella Serotype Oranienburg Strain During Cocoa Roasting at Conditions Relevant to the Fine Chocolate Industry. Front Microbiol 2021; 12:576337. [PMID: 33763036 PMCID: PMC7982832 DOI: 10.3389/fmicb.2021.576337] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 02/04/2021] [Indexed: 12/31/2022] Open
Abstract
Cocoa roasting produces and enhances distinct flavor of chocolate and acts as a critical control point for inactivation of foodborne pathogens in chocolate production. In this study, the inactivation kinetics of Salmonella enterica subsp. enterica serotype Oranienburg strain was assessed on whole cocoa beans using roasting protocols relevant to the fine chocolate industry. Beans were inoculated with 107-108 log10 CFU/bean of Salmonella Oranienburg and roasted at 100-150°C for 2-100 min. A greater than 5 log10 reduction of S. Oranienburg was experimentally achieved after 10-min roasting at 150°C. Data were fitted using log-linear and Weibull models. The log-linear models indicated that the roasting times (D) needed to achieve a decimal reduction of Salmonella at 100, 110, 115, 120, 130, and 140°C were 33.34, 18.57, 12.92, 10.50, 4.20, and 1.90 min, respectively. A Weibull model indicated a decrease in the Salmonella inactivation rate over time (β < 1). Statistical analysis indicated that the Weibull model fitted the data better compared to a log-linear model. These data demonstrate the efficacy of cocoa roasting in inactivation of Salmonella and may be used to guide food safety decision-making.
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Affiliation(s)
- Runan Yan
- Department of Food Science, The Pennsylvania State University, University Park, PA, United States
| | - Gabriella Pinto
- Department of Food Science, The Pennsylvania State University, University Park, PA, United States
| | | | - Karen Cogan
- Dandelion Chocolate Inc., San Francisco, CA, United States
| | | | - Jasna Kovac
- Department of Food Science, The Pennsylvania State University, University Park, PA, United States
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20
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Igo MJ, Schaffner DW. Models for factors influencing pathogen survival in low water activity foods from literature data are highly significant but show large unexplained variance. Food Microbiol 2021; 98:103783. [PMID: 33875211 DOI: 10.1016/j.fm.2021.103783] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 03/02/2021] [Accepted: 03/03/2021] [Indexed: 11/19/2022]
Abstract
Factors that control pathogen survival in low water activity foods are not well understood and vary greatly from food to food. A literature search was performed to locate data on the survival of foodborne pathogens in low-water activity (<0.70) foods held at temperatures <37 °C. Data were extracted from 67 publications and simple linear regression models were fit to each data set to estimate log linear rates of change. Multiple linear stepwise regression models for factors influencing survival rate were developed. Subset regression modeling gave relatively low adjusted R2 values of 0.33, 0.37, and 0.48 for Salmonella, E. coli and L. monocytogenes respectively, but all subset models were highly significant (p < 1.0e-9). Subset regression models showed that Salmonella survival was significantly (p < 0.05) influenced by temperature, serovar and strain type, water activity, inoculum preparation method, and inoculation method. E. coli survival was significantly influenced by temperature, water activity, and inoculum preparation. L. monocytogenes survival was significantly influenced by temperature, serovar and strain type, and inoculum preparation method. While many factors were highly significant (p < 0.001), the high degrees of variability show that there is still much to learn about the factors which govern pathogen survival in low water activity foods.
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Affiliation(s)
- Matthew J Igo
- Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, NJ, 08901, USA
| | - Donald W Schaffner
- Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, NJ, 08901, USA.
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21
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Steghöfer S, Limburn R, Margas E. Microbiological assessment of heat treatment of broiler mash at laboratory scale to evaluate Salmonella reduction during feed conditioning. J APPL POULTRY RES 2021. [DOI: 10.1016/j.japr.2020.100122] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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22
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Wei X, Agarwal S, Subbiah J. Evaluation of Enterococcus faecium NRRL B-2354 as a surrogate for Salmonella enterica in milk powders at different storage times and temperatures. J Dairy Sci 2021; 104:198-210. [DOI: 10.3168/jds.2020-19190] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/02/2020] [Indexed: 01/15/2023]
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23
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Yang R, Xu J, Lombardo SP, Ganjyal GM, Tang J. Desiccation in oil protects bacteria in thermal processing. Food Res Int 2020; 137:109519. [PMID: 33233153 DOI: 10.1016/j.foodres.2020.109519] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/30/2020] [Accepted: 07/02/2020] [Indexed: 11/30/2022]
Abstract
Edible oils have long been considered to have a protective effect on bacteria from thermal inactivation, but the mechanism for this effect remains unclear. Our recent study suggests that the water activity (aw) of oil decreases exponentially with increasing temperature. Therefore, in thermal processing, the aw of the bacteria inside oil may also decrease making the bacteria more resistant to heat. To validate this hypothesis, the equilibrium aw of bacteria (Enterococcus faecium NRRL B2354, or E. faecium) in peanut oil samples, with different initial aw (0.93, 0.75, 0.52 & 0.33) at room temperature, were measured at elevated temperatures up to 80 °C. Meanwhile, the thermal resistances of E. faecium in these samples were also tested at 80 °C. Results indicate that the aw of the bacteria-in-oil systems changed in the same manner as that of pure peanut oil; it decreased exponentially with temperature from 0.93, 0.75, 0.52 & 0.33 (at ~23 °C) to 0.36, 0.30, 0.21 & 0.13 (at 80 °C), respectively. This confirmed that bacterial cells experienced desiccation in oil during the thermal treatments. The thermal death rates of E. faecium in peanut oil samples followed first-order kinetics. The D80 value (time needed to achieve 1-log reduction at 80 °C) increased exponentially with the reduced aw at 80 °C, from 87 min at aw 0.36 to 1539 min at aw 0.13. A graphical comparison (logD80 vs. high-temperature aw) showed a similarity between the thermal resistance of E. faecium in oil and that in dry air, which supports the hypothesis that oil protects bacteria from thermal treatments through desiccation.
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Affiliation(s)
- Ren Yang
- Department of Biological Systems Engineering, Washington State University, P.O. Box 646120, Pullman, WA 99164-6120, USA
| | - Jie Xu
- Department of Biological Systems Engineering, Washington State University, P.O. Box 646120, Pullman, WA 99164-6120, USA
| | - Stephen P Lombardo
- Technical Innovation Center, McCormick & Company, Inc., Hunt Valley, MD 21031, USA
| | - Girish M Ganjyal
- School of Food Science, Washington State University, P.O. Box 646376, Pullman, WA 99164-6376, USA
| | - Juming Tang
- Department of Biological Systems Engineering, Washington State University, P.O. Box 646120, Pullman, WA 99164-6120, USA.
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24
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Pelaez MAB, Anapi GR, Bautista DV, Dallo MDP, Libunao JCM, Gabriel AA. Thermal inactivation of Salmonella enterica in Philippine flowing-type peanut butter. Lebensm Wiss Technol 2020. [DOI: 10.1016/j.lwt.2020.109507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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25
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Olaimat AN, Osaili TM, Al-Holy MA, Al-Nabulsi AA, Obaid RS, Alaboudi AR, Ayyash M, Holley R. Microbial safety of oily, low water activity food products: A review. Food Microbiol 2020; 92:103571. [PMID: 32950156 DOI: 10.1016/j.fm.2020.103571] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/17/2020] [Accepted: 06/13/2020] [Indexed: 12/25/2022]
Abstract
Oily, low water activity (OL aw) products including tahini (sesame seed paste), halva (tahini halva), peanut butter, and chocolate, have been recently linked to numerous foodborne illness outbreaks and recalls. This review discusses the ingredients used and processing of OL aw products with a view to provide greater understanding of the routes of their contamination with foodborne pathogens and factors influencing pathogen persistence in these foods. Adequate heat treatment during processing may eliminate bacterial pathogens from OL aw foods; however, post-processing contamination commonly occurs. Once these products are contaminated, their high fat and sugar content can enhance pathogen survival for long periods. The physiological basis and survival mechanisms used by pathogens in these products are comprehensively discussed here. Foodborne outbreaks and recalls linked to OL aw foods are summarized and it was observed that serotypes of Salmonella enterica were the predominant pathogens causing illnesses. Further, intervention strategies available to control foodborne pathogens such as thermal inactivation, use of natural antimicrobials, irradiation and hydrostatic pressure are assessed for their usefulness to achieve pathogen control and enhance the safety of OL aw foods. Sanitation, hygienic design of manufacturing facilities, good hygienic practices, and environmental monitoring of OL aw food industries were also discussed.
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Affiliation(s)
- Amin N Olaimat
- Department of Clinical Nutrition and Dietetics, Faculty of Applied Medical Sciences, The Hashemite University, P.O. Box 150459, Zarqa, 13115, Jordan.
| | - Tareq M Osaili
- Department of Clinical Nutrition and Dietetics, College of Health Science, University of Sharjah, Sharjah, United Arab Emirates; Department of Nutrition and Food Technology, Jordan University of Science and Technology, P.O. Box 3030, Irbid, 22110, Jordan.
| | - Murad A Al-Holy
- Department of Clinical Nutrition and Dietetics, Faculty of Applied Medical Sciences, The Hashemite University, P.O. Box 150459, Zarqa, 13115, Jordan
| | - Anas A Al-Nabulsi
- Department of Nutrition and Food Technology, Jordan University of Science and Technology, P.O. Box 3030, Irbid, 22110, Jordan
| | - Reyad S Obaid
- Department of Clinical Nutrition and Dietetics, College of Health Science, University of Sharjah, Sharjah, United Arab Emirates
| | - Akram R Alaboudi
- Department of Pathology and Public Health, Faculty of Veterinary Medicine, Jordan University of Science and Technology, P.O. Box 3030, Irbid, 22110, Jordan
| | - Mutamed Ayyash
- Department of Food, Nutrition and Health, College of Food and Agriculture, United Arab Emirates University (UAEU), Al Ain, UAE
| | - Richard Holley
- Department of Food Science and Human Nutrition, University of Manitoba, Winnipeg, Manitoba, R2J 3L8, Canada
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26
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Lee K, Shoda M, Kawai K, Koseki S. Relationship between glass transition temperature, and desiccation and heat tolerance in Salmonella enterica. PLoS One 2020; 15:e0233638. [PMID: 32469949 PMCID: PMC7259547 DOI: 10.1371/journal.pone.0233638] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 05/08/2020] [Indexed: 11/19/2022] Open
Abstract
Pathogenic bacteria such as Salmonella enterica exhibit high desiccation tolerance, enabling long-term survival in low water activity (aw) environments. Although there are many reports on the effects of low aw on bacterial survival, the mechanism by which bacteria acquire desiccation tolerance and resistance to heat inactivation in low-aw foods remains unclear. We focused on the glass transition phenomenon, as bacteria may acquire environmental tolerance by state change due to glass transition. In this study, we determined the glass transition temperature (Tg) in S. enterica serovars under different aw conditions using thermal rheological analysis (TRA). The softening behaviour associated with the state change of bacterial cells was confirmed by TRA, and Tg was determined from the softening behaviour. Tg increased as the aw decreased in all S. enterica serovars. For example, while the Tg of five S. enterica serovars was determined as 35.16°C to 57.46°C at 0.87 aw, the Tg of all the five serovars increased by 77.10°C to 83.30°C at 0.43 aw. Furthermore, to verify the thermal tolerance of bacterial cells, a thermal inactivation assay was conducted at 60°C for 10 min under each aw condition. A higher survival ratio was observed as aw decreased; this represented an increase in Tg for Salmonella strains. These results suggest that the glass transition phenomenon of bacterial cells would associate with environmental tolerance.
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Affiliation(s)
- Kyeongmin Lee
- Graduate School of Agricultural Science, Hokkaido University, Sapporo, Japan
| | - Masaki Shoda
- Graduate School of Agricultural Science, Hokkaido University, Sapporo, Japan
| | - Kiyoshi Kawai
- Graduate School of Integrated Sciences for Life, Hiroshima University, Higashi-Hiroshima, Hiroshima, Japan
| | - Shigenobu Koseki
- Graduate School of Agricultural Science, Hokkaido University, Sapporo, Japan
- * E-mail:
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27
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Screening of non-pathogenic surrogates of Listeria monocytogenes applicable for chemical antimicrobial interventions of fresh apples. Food Control 2020. [DOI: 10.1016/j.foodcont.2019.106977] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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28
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Ahmed S, Downs S, Fanzo J. Advancing an Integrative Framework to Evaluate Sustainability in National Dietary Guidelines. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2019. [DOI: 10.3389/fsufs.2019.00076] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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29
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Tsai HC, Ballom KF, Xia S, Tang J, Marks BP, Zhu MJ. Evaluation of Enterococcus faecium NRRL B-2354 as a surrogate for Salmonella during cocoa powder thermal processing. Food Microbiol 2019; 82:135-141. [DOI: 10.1016/j.fm.2019.01.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Revised: 01/07/2019] [Accepted: 01/11/2019] [Indexed: 10/27/2022]
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30
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Deen B, Diez-Gonzalez F. Assessment of Pediococcus acidilactici ATCC 8042 as potential Salmonella surrogate for thermal treatments of toasted oats cereal and peanut butter. Food Microbiol 2019; 83:187-192. [PMID: 31202412 DOI: 10.1016/j.fm.2019.05.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 04/19/2019] [Accepted: 05/26/2019] [Indexed: 10/26/2022]
Abstract
The control of Salmonella in low water activity foods poses a challenge for the food industry because of its thermal resistance. The use of surrogate bacteria in a food plant is considered a critical component to validate processing steps. The objective of this study was to evaluate the use of Pediococcus acidilactici ATCC 8042, a generally recognized as safe bacterium (GRAS), as potential surrogate for Salmonella in commercial toasted oats cereal (TOC) and peanut butter. P. acidilactici was compared to a five-serovar cocktail of Salmonella and Enterococcus faecium NRRL-B2354, separately. Cultures were inoculated into TOC and thermal kinetic parameters (δ, β) were determined at 80, 85, 90, and 95 °C using the Weibull model. In peanut butter, δ and β parameters were obtained at 63, 68, 73, and 77 °C. In TOC, the δ values (initial decimal reduction time) of P. acidilactici were 63 and 7 min at 80 and 95 °C, respectively, and at all four temperatures they were not significantly different from δ values of E. faecium. The δ value of Salmonella at 80 °C (139 min) was two-fold greater than the other two bacteria's values (p < 0.05). In peanut butter, δ values of P. acidilactici ranged from 31 min at 63 °C to 2.6 min at 77 °C, and at all temperatures they were not significantly different from E. faecium's δ values. In peanut butter, all Salmonella cocktail's δ values were significantly smaller than P. acidilactici's with values of 2 min at 63 °C and 0.4 min at 77 °C. These results indicated that P. acidilactici was as heat tolerant as E. faecium in these food matrices. However, the thermal inactivation kinetic parameters suggested that P. acidilactici can only be considered a Salmonella surrogate in TOC at temperatures above 85 °C. Because of its greater thermal tolerance in peanut butter, P. acidilactici may be used as Salmonella surrogate if an additional safety factor is recommended.
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Affiliation(s)
- Bronwyn Deen
- Center for Food Safety, Department of Food Science and Technology, University of Georgia, Griffin, GA, 30223, USA
| | - Francisco Diez-Gonzalez
- Center for Food Safety, Department of Food Science and Technology, University of Georgia, Griffin, GA, 30223, USA.
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31
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Xu J, Tang J, Jin Y, Song J, Yang R, Sablani SS, Zhu MJ. High temperature water activity as a key factor influencing survival of Salmonella Enteritidis PT30 in thermal processing. Food Control 2019. [DOI: 10.1016/j.foodcont.2018.11.054] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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32
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Forghani F, den Bakker M, Liao JY, Payton AS, Futral AN, Diez-Gonzalez F. Salmonella and Enterohemorrhagic Escherichia coli Serogroups O45, O121, O145 in Wheat Flour: Effects of Long-Term Storage and Thermal Treatments. Front Microbiol 2019; 10:323. [PMID: 30853953 PMCID: PMC6395439 DOI: 10.3389/fmicb.2019.00323] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 02/07/2019] [Indexed: 01/09/2023] Open
Abstract
Salmonella and enterohemorrhagic Escherichia coli (EHEC) are of serious concern in wheat flour and its related products but little is known on their survival and thermal death kinetics. This study was undertaken to determine their long-term viability and thermal inactivation kinetics in flour. Inoculation was performed using mixtures of EHEC serogroups O45, O121, O145 and Salmonella followed by storage at room temperature (23°C) or 35°C (for Salmonella). Plate counting on tryptic soy agar (TSA) and enrichment were used to assess long-term survival. For thermal studies, wheat flour samples were heated at 55, 60, 65, and 70°C and cell counts of EHEC and Salmonella were determined by plating. The δ-values were calculated using the Weibull model. At room temperature, EHEC serovars and Salmonella were quantifiable for 84 and 112 days, and were detectable for the duration of the experiment after 168 and 365 days, respectively. The δ-values were 2.0, 5.54, and 9.3 days, for EHEC O121, O45, and O145, respectively, and 9.7 days for Salmonella. However, the only significant difference among all values was the δ-value for Salmonella and serogroup O121 (p ≤ 0.05). At 35°C, Salmonella counts declined to unquantifiable levels after a week and were not detected upon enrichment after 98 days. Heat treatment of inoculated wheat flour at 55, 60, 65, and 70°C resulted in δ-value ranges of 20.0-42.9, 4.9-10.0, 2.4-3.2, and 0.2-1.6 min, respectively, for EHEC. The δ-values for Salmonella at those temperatures were 152.2, 40.8, 17.9, and 17.4 min, respectively. The δ-values obtained for Salmonella at each temperature were significantly longer than for EHEC (p ≤ 0.05). Weibull model was a good fit to describe the thermal death kinetics of Salmonella and EHEC O45, O121 and O145 in wheat flour. HIGHLIGHTS -EHEC and Salmonella can survive for extended periods of time in wheat flour.-Long-term storage inactivation curves of EHEC and Salmonella were similar.-EHEC was more sensitive to heat than Salmonella.-Weibull model was a good fit to describe thermal death kinetics of EHEC and Salmonella.-Flour storage at 35°C may be a feasible method for microbial reduction.
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Affiliation(s)
- Fereidoun Forghani
- Center for Food Safety, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, GA, United States
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33
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Kapetanakou AE, Makariti IP, Nazou EΝ, Manios SG, Karavasilis K, Skandamis PN. Modelling the effect of osmotic adaptation and temperature on the non-thermal inactivation of Salmonella spp. on brioche-type products. Int J Food Microbiol 2019; 296:48-57. [PMID: 30849706 DOI: 10.1016/j.ijfoodmicro.2019.02.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 12/27/2018] [Accepted: 02/12/2019] [Indexed: 11/24/2022]
Abstract
Salmonella spp. is known to survive in intermediate- and low-moisture foods. Bakery products such as cream-filled brioche (aw 0.82-0.84), depending mainly on the aw of the fillings and the baking they receive for food preservation, may support survival of the pathogen. The study aimed to model the inactivation of osmotically adapted and non-adapted Salmonella in cream-fillings (praline and biscuit) and cream-filled brioche at different storage temperatures. All matrices were inoculated with ca. 6.0 log CFU/g of osmotically adapted and non-adapted five-strain cocktail of Salmonella (Typhimurium, Agona, Reading, and Enteritidis) and stored aerobically in 120 mL screw-capped containers at 15, 20, and 30 °C. Adaptation of Salmonella was induced in cream-fillings (praline and biscuit) with aw adjusted to 0.88, by adding sterile water to each of the original fillings (aw 0.78-0.83) and incubating at 37 °C for 1 h. Survival of Salmonella was assessed at regular time intervals throughout storage using thin layer agar method to enhance the recovery of injured cells (n = 4). Inactivation curves were fitted best with the Weibull model using the freeware GInaFit tool and the estimated δ and β values were used to calculate the time for 4D reduction-t4D. Results showed that inactivation of Salmonella increased with temperature, while osmotic adaptation enhanced its survival in a food matrix-related manner. Higher survival rates of adapted cells were observed in cream-fillings (t4D: 79.9 ± 27.1 days on biscuit and 150.3 ± 19.6 days on praline) compared to brioche (t4D: 61.3 ± 0.9 days on biscuit and 52.5 ± 4.6 days on praline) at 20 °C. Secondary (linear) modelling of t4D showed that the survival of Salmonella was affected by temperature and osmotic adaptation. Model simulation of pathogen inactivation in independent trials on cream-fillings agreed well with observed data. In conclusion, the present data could be used as a means to identify areas for improving the performance of existing models quantifying the survival of Salmonella in bakery-confectionary products with intermediate aw.
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Affiliation(s)
- Anastasia E Kapetanakou
- Laboratory of Food Quality Control and Hygiene, Department of Food Technology & Human Science, Agricultural University of Athens, Greece
| | - Ifigeneia P Makariti
- Laboratory of Food Quality Control and Hygiene, Department of Food Technology & Human Science, Agricultural University of Athens, Greece
| | - Eleftheria Ν Nazou
- Laboratory of Food Quality Control and Hygiene, Department of Food Technology & Human Science, Agricultural University of Athens, Greece
| | | | | | - Panagiotis N Skandamis
- Laboratory of Food Quality Control and Hygiene, Department of Food Technology & Human Science, Agricultural University of Athens, Greece.
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Limcharoenchat P, James MK, Marks BP. Survival and Thermal Resistance of Salmonella Enteritidis PT 30 on Almonds after Long-Term Storage. J Food Prot 2019; 82:194-199. [PMID: 30667289 DOI: 10.4315/0362-028x.jfp-18-152] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Salmonella survival and thermal resistance on the surface of almond kernels were evaluated after periods of storage. Almond kernels were inoculated with Salmonella Enteritidis PT 30 and equilibrated to 0.45 water activity. Samples were separated into two groups (I and II) and stored in sealed metal cans at room temperature. Group I samples (stored 7, 15, 27, and 68 weeks) were re-equilibrated in controlled humidity chambers to 0.45 water activity before performing the thermal treatments after each storage period, but group II samples (stored 70 and 103 weeks) were thermally treated immediately after the cans were opened. For thermal treatments, individual almond kernels were vacuum sealed in thin plastic bags, heated isothermally in a water bath (80°C) for nine intervals, immediately cooled in an ice bath, and assayed for surviving Salmonella. Log-linear and Weibull models were fit to the inactivation data. Salmonella population decreased ( P < 0.05) more than 2 log CFU/g during the long-term storage. Salmonella survival in group II at 70 weeks (7.3 log CFU/g) was higher ( P < 0.05) than in group I (which had been re-equilibrated multiple times) at 68 weeks (6.2 log CFU/g). However, the thermal resistance of Salmonella Enteritidis PT 30 did not decrease ( P > 0.05) for up to 68 weeks of storage, and the log-linear model best described the thermal inactivation data. Overall, the results suggest that re-equilibrating almonds (group I) multiple times may have increased the rate of reduction of Salmonella populations during long-term storage. However, Salmonella thermal resistance on almonds appears to be essentially unaffected by long-term storage, which is important information for designing and conducting validation studies for pathogen control processes.
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Affiliation(s)
- Pichamon Limcharoenchat
- Department of Biosystems and Agricultural Engineering, Michigan State University, 524 South Shaw Lane, East Lansing, Michigan 48824, USA
| | - Michael K James
- Department of Biosystems and Agricultural Engineering, Michigan State University, 524 South Shaw Lane, East Lansing, Michigan 48824, USA
| | - Bradley P Marks
- Department of Biosystems and Agricultural Engineering, Michigan State University, 524 South Shaw Lane, East Lansing, Michigan 48824, USA
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Wang P, Goggins WB, Chan EYY. Associations of Salmonella hospitalizations with ambient temperature, humidity and rainfall in Hong Kong. ENVIRONMENT INTERNATIONAL 2018; 120:223-230. [PMID: 30103121 DOI: 10.1016/j.envint.2018.08.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/04/2018] [Accepted: 08/02/2018] [Indexed: 05/26/2023]
Abstract
BACKGROUND Little is known about the relationship between Salmonella infection and meteorological parameters other than air temperature. This study aimed to explore associations of Salmonella hospitalizations with temperature, relative humidity (RH) and rainfall. METHODS With negative binomial distribution assumed, time-series regression model adjusting for season and time trend were constructed employing distributed lag non-linear models and generalized additive models. Meteorological variables including mean temperature, RH, and daily total rainfall as well as indicator variables including day of the week and public holiday were incorporated in the models. RESULTS Higher temperature was strongly associated with more hospitalizations over the entire range of temperatures observed. There was a net 6.13 (95%Confidence Interval (CI) 3.52-10.67) relative risk of hospitalization at a temperature of 30.5 °C, relative to 13 °C, lag 0-16 days. Positive associations were found for RH above 60% and rainfall between 0 and 0.14 mm. Extreme high humidity (96%) and trace rainfall (0.02 mm) were associated with 2.06 (95%CI 1.35-3.14), lag 0-17 day, and 1.30 (95%CI 1.01-1.67), lag 0-26 days, relative risks of hospitalizations, relative to 60% and no rain, respectively. CONCLUSIONS High temperatures, high RH and light rainfall are positively associated with Salmonella hospitalizations. The very strong association with temperatures implies that hotter days will lead to increases in Salmonella morbidity in the absence of other changes, and the public health implications of this could be exacerbated by global climate change.
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Affiliation(s)
- Pin Wang
- School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - William B Goggins
- School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
| | - Emily Y Y Chan
- Collaborating Centre for Oxford University and CUHK for Disaster and Medical Humanitarian Response, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
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36
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Jin Y, Pickens SR, Hildebrandt IM, Burbick SJ, Grasso-Kelley EM, Keller SE, Anderson NM. Thermal Inactivation of Salmonella Agona in Low-Water Activity Foods: Predictive Models for the Combined Effect of Temperature, Water Activity, and Food Component. J Food Prot 2018; 81:1411-1417. [PMID: 30059253 DOI: 10.4315/0362-028x.jfp-18-041] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Salmonella can survive in low-moisture, high-protein, and high-fat foods for several years. Despite nationwide outbreaks and recalls due to the presence of Salmonella in low-moisture foods, information on thermal inactivation of Salmonella in these products is limited. This project evaluated the impact of water activity (aw), temperature, and food composition on thermal inactivation of Salmonella enterica serovar Agona in defined high-protein and high-fat model food matrices. Each matrix was inoculated with Salmonella Agona and adjusted to obtain a target aw, ranging from 0.50 to 0.98. Samples were packed into aluminum test cells and heated (52 to 90°C) under isothermal conditions. Survival of Salmonella Agona was detected on tryptic soy agar with 0.6% yeast extract. Complex influences by food composition, aw, and temperature resulted in significantly different ( P < 0.05) thermal resistance of Salmonella for the conditions tested. It was estimated that the same point temperatures at which the D-values of the two matrices at each aw (0.63, 0.73, 0.81, and 0.90) were identical were 79.48, 71.28, 69.62, and 38.42°C, respectively. Above these temperatures, the D-values in high-protein matrices were larger than the D-values in high-fat matrices at each aw. Below these temperatures, the inverse relationship was observed. A correlation between temperature and aw existed on the basis of the level of fat or protein in the food, showing that these compositional factors must be accounted for when predicating thermal inactivation of Salmonella in foods.
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Affiliation(s)
- Yuqiao Jin
- 1 Illinois Institute of Technology, Institute of Food Safety and Health, and
| | - Shannon R Pickens
- 1 Illinois Institute of Technology, Institute of Food Safety and Health, and
| | - Ian M Hildebrandt
- 2 U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Stephen J Burbick
- 2 U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | | | - Susanne E Keller
- 2 U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Nathan M Anderson
- 2 U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
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Newkirk JJ, Wu J, Acuff JC, Caver CB, Mallikarjunan K, Wiersema BD, Williams RC, Ponder MA. Inactivation of Salmonella enterica and Surrogate Enterococcus faecium on Whole Black Peppercorns and Cumin Seeds Using Vacuum Steam Pasteurization. FRONTIERS IN SUSTAINABLE FOOD SYSTEMS 2018. [DOI: 10.3389/fsufs.2018.00048] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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38
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Forghani F, den Bakker M, Futral AN, Diez-Gonzalez F. Long-Term Survival and Thermal Death Kinetics of Enterohemorrhagic Escherichia coli Serogroups O26, O103, O111, and O157 in Wheat Flour. Appl Environ Microbiol 2018; 84:e00283-18. [PMID: 29678913 PMCID: PMC6007106 DOI: 10.1128/aem.00283-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 04/12/2018] [Indexed: 11/20/2022] Open
Abstract
Wheat flour has been associated with outbreaks of enterohemorrhagic Escherichia coli (EHEC), but little is known on EHEC's survival during storage and thermal processing. The objective of this study was to determine long-term viability and thermal inactivation kinetics of EHEC serogroups O26, O103, O111, and O157. Wheat flour samples were inoculated with a cocktail of five strains of a single serogroup and stored at 23 and 35°C. Inoculated samples were heated at 55, 60, 65, and 70°C. Viability was determined by plate counting. Decimal reduction time (D) and first decimal reduction time (δ) values were calculated with log-linear and Weibull models, respectively. At 23°C, EHEC counts declined gradually for 84 days and samples tested positive from 84 to 280 days. The thermal resistance (D and δ) values ranged from 7.5 to 8.2 and 3.1 to 5.3 days, respectively, but there were no significant differences among serogroups (P ≤ 0.05). At 35°C, no EHEC was quantifiable by day 7 and no positive samples were detected after 49 days. Heating at 55 and 65°C resulted in δ-value ranges of 15.6 to 39.7 min and 3.0 to 3.9 min, respectively, with no significant difference among serogroups either. Z values were 12.6, 6.7, 10.2, and 13.4°C for O26, O103, O111, and O157, respectively. Thermal death kinetics of EHEC in flour were better described using the Weibull model. Survival and inactivation rates of four serogroups were remarkably similar. These findings indicated that all EHEC serovars tested remained viable for at least 9 months at room temperature and survived for up to 60 min at 70°C in wheat flour.IMPORTANCE Enterohemorrhagic Escherichia coli (EHEC) and Salmonella have recently caused several gastroenteritis outbreaks and recalls of wheat flour. Because EHEC can cause illness with very low doses and there is very scarce information regarding their ability to survive storage and heating in flour, the present study was undertaken to assess the long-term survival of EHEC serogroups O26, O103, O111, and O157 in flour. These findings are relevant, as we report that EHEC can survive for more than 9 months in wheat flour during storage. In addition, results obtained suggest that thermal inactivation at 65°C for 30 min or 2 months of storage at 35°C may be feasible strategies to mitigate the risk of most EHEC serovars in wheat flour.
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Affiliation(s)
- Fereidoun Forghani
- Center for Food Safety, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, Georgia, USA
| | - Meghan den Bakker
- Center for Food Safety, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, Georgia, USA
| | - Alexandra N Futral
- Center for Food Safety, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, Georgia, USA
| | - Francisco Diez-Gonzalez
- Center for Food Safety, College of Agricultural and Environmental Sciences, University of Georgia, Griffin, Georgia, USA
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Liu S, Tang J, Tadapaneni RK, Yang R, Zhu MJ. Exponentially Increased Thermal Resistance of Salmonella spp. and Enterococcus faecium at Reduced Water Activity. Appl Environ Microbiol 2018; 84:e02742-17. [PMID: 29439987 PMCID: PMC5881056 DOI: 10.1128/aem.02742-17] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 02/01/2018] [Indexed: 01/13/2023] Open
Abstract
Salmonella spp. exhibit prolonged survivability and high tolerance to heat in low-moisture foods. The reported thermal resistance parameters of Salmonella spp. in low-moisture foods appear to be unpredictable due to various unknown factors. We report here that temperature-dependent water activity (aw, treatment temperature) plays an important role in the sharply increased thermal resistance of Salmonella enterica serovar Enteritidis PT 30 and its potential surrogate Enterococcus faecium NRRL B-2354. In our study, silicon dioxide granules, as carriers, were separately inoculated with these two microorganisms and were heated at 80°C with controlled relative humidity between 18 and 72% (resulting in corresponding aw,80°C values for bacteria between 0.18 and 0.72) in custom-designed test cells. The inactivation kinetics of both microorganisms fitted a log-linear model (R2, 0.83 to 0.97). Reductions in the aw,80°C values of bacterial cells exponentially increased the D80°C (the time needed to achieve a 1-log reduction in a bacterial population at 80°C) values for S Enteritidis and E. faecium on silicon dioxide. The log-linear relationship between the D80°C values for each strain in silicon dioxide and its aw,80°C values was also verified for organic wheat flour. E. faecium showed consistently higher D80°C values than S Enteritidis over the aw,80°C range tested. The estimated zaw (the change in aw,80°C needed to change D80°C by 1 log) values of S Enteritidis and E. faecium were 0.31 and 0.28, respectively. This study provides insight into the interpretation of Salmonella thermal resistance that could guide the development and validation of thermal processing of low-moisture foods.IMPORTANCE In this paper, we established that the thermal resistance of the pathogen S Enteritidis and its surrogate Enterococcus faecium, as reflected by D values at 80°C, increases sharply with decreasing relative humidity in the environment. The log-linear relationship between the D80°C values of each strain in silicon dioxide and its aw,80°C values was also verified for organic wheat flour. The results provide new quantitative insight into the way in which the thermal resistance of microorganisms changes in low-moisture systems, and they should aid in the development of effective thermal treatment strategies for pathogen control in low-moisture foods.
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Affiliation(s)
- Shuxiang Liu
- Department of Biological Systems Engineering, Washington State University, Pullman, Washington, USA
| | - Juming Tang
- Department of Biological Systems Engineering, Washington State University, Pullman, Washington, USA
| | - Ravi Kiran Tadapaneni
- Department of Biological Systems Engineering, Washington State University, Pullman, Washington, USA
| | - Ren Yang
- Department of Biological Systems Engineering, Washington State University, Pullman, Washington, USA
| | - Mei-Jun Zhu
- School of Food Science, Washington State University, Pullman, Washington, USA
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40
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Limcharoenchat P, Buchholz SE, James MK, Hall NO, Ryser ET, Marks BP. Inoculation Protocols Influence the Thermal Resistance of Salmonella Enteritidis PT 30 in Fabricated Almond, Wheat, and Date Products. J Food Prot 2018; 81:606-613. [PMID: 29528705 DOI: 10.4315/0362-028x.jfp-17-297] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Inoculation methods in pathogen inactivation studies ideally represent conditions that might occur in real-world scenarios. Surface contamination in or on low-moisture foods affects Salmonella thermal resistance, which is critically important for process validation applications. The objective of this study was to quantify the effect of inoculation protocol on the thermal resistance of Salmonella Enteritidis PT 30 in fabricated low-moisture foods. Almond meal, almond butter, wheat meal, wheat flour, and date paste were inoculated via prefabrication and postfabrication protocols. In the prefabrication protocol, kernels and fruits were surface inoculated and equilibrated to a target water activity (aw) (0.40 for almond and wheat products, 0.45 for date products) before fabricating meal, butter, flour, or paste and then reequilibrating the samples to the target aw. In the postfabrication protocol, meal, butter, flour, and paste were fabricated before inoculation and equilibration. All inoculated and equilibrated samples were subjected to isothermal treatment (80°C), pulled sequentially during processing, cooled, serially diluted, and plated to enumerate survivors. Log-linear and Weibull-type models were fit to the Salmonella survivor data and were compared via the corrected Akaike information criterion. Pre- and postfabrication protocols resulted in significant differences ( P < 0.05) in Salmonella thermal resistance in all products. Overall, the thermal resistance of Salmonella Enteritidis PT 30 in almond products was greater ( P < 0.05) than in wheat products, which was also greater ( P < 0.05) than in date paste. Additionally, Salmonella was more thermally resistant in almond products and date paste when inoculated pre- rather than postfabrication; however, the opposite was true for wheat products. These results indicate that the means of inoculation can significantly affect thermal resistance of Salmonella in low-moisture foods.
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Affiliation(s)
| | | | | | - Nicole O Hall
- 1 Department of Biosystems and Agricultural Engineering and
| | - Elliot T Ryser
- 2 Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824, USA (ORCID: http://orcid.org/0000-0003-1337-2658 [E.T.R.])
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41
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Liu S, Rojas RV, Gray P, Zhu MJ, Tang J. Enterococcus faecium as a Salmonella surrogate in the thermal processing of wheat flour: Influence of water activity at high temperatures. Food Microbiol 2018; 74:92-99. [PMID: 29706342 DOI: 10.1016/j.fm.2018.03.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 03/02/2018] [Accepted: 03/02/2018] [Indexed: 11/19/2022]
Abstract
This study investigated the influence of temperature-dependent water activity (aw) on thermal resistances of Enterococcus faecium NRRL B-2354 (E. faecium) and Salmonella Enteritidis PT 30 (S. Enteritidis) in wheat flour. The aw for wheat flour samples at 20, 40, and 60 °C was determined by a vapor sorption analyzer and at 75, 80 and 85 °C using custom-built thermal cells with high temperature humidity sensors. Full-factorial isothermal inactivation studies of both strains in sealed aluminum-test-cells included three temperatures (75, 80, and 85 °C) and three aw,25°C levels (0.30, 0.45 and 0.60 within ±0.02 range, prior to the thermal treatments). Isotherm results of wheat flour demonstrate a significant increase (P < 0.05) of aw as temperature rises (e.g. aw,25°C = 0.45 ± 0.02 became aw,80°C = 0.71 ± 0.02 in a closed system). Inactivation kinetics of both microorganisms fitted a log-linear model, the yielded D-values varied from 2.7 ± 0.2 min (D85°C of S. Enteritidis at aw,25°C 0.60 ± 0.02) to 65.8 ± 2.5 min (D75°C of E. faecium at aw,25°C 0.30 ± 0.02). The zT of E. faecium and S. Enteritidis decreased from 16.4 and 16.9 °C, respectively, to 10.2 °C with increased moisture content (dry basis) from 10 to 14%. Under all tested conditions, E. faecium exhibited equal or higher (1.0-3.1 times) D- and zT-values than those of Salmonella. Overall, E. faecium should be a conservative surrogate for Salmonella in thermal processing of wheat flour for control of Salmonella over a moisture content of 10-14% and treatment temperatures between 75 and 85 °C.
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Affiliation(s)
- Shuxiang Liu
- Department of Biological Systems Engineering, Washington State University, Pullman, WA, USA
| | - Rossana V Rojas
- Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Monterrey, Nuevo León, Mexico
| | - Peter Gray
- Department of Biological Systems Engineering, Washington State University, Pullman, WA, USA; School of Food Science, Washington State University, Pullman, WA, USA
| | - Mei-Jun Zhu
- School of Food Science, Washington State University, Pullman, WA, USA.
| | - Juming Tang
- Department of Biological Systems Engineering, Washington State University, Pullman, WA, USA.
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42
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Nascimento M, Carminati J, Silva I, Silva D, Bernardi A, Copetti M. Salmonella , Escherichia coli and Enterobacteriaceae in the peanut supply chain: From farm to table. Food Res Int 2018; 105:930-935. [DOI: 10.1016/j.foodres.2017.12.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 12/05/2017] [Accepted: 12/08/2017] [Indexed: 11/29/2022]
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43
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Nascimento MS, Carminati JA, Morishita KN, Amorim Neto DP, Pinheiro HP, Maia RP. Long-term kinetics of Salmonella Typhimurium ATCC 14028 survival on peanuts and peanut confectionery products. PLoS One 2018; 13:e0192457. [PMID: 29401480 PMCID: PMC5798841 DOI: 10.1371/journal.pone.0192457] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 01/23/2018] [Indexed: 11/19/2022] Open
Abstract
Due to recent large outbreaks, peanuts have been considered a product of potential risk for Salmonella. Usually, peanut products show a low water activity (aw) and high fat content, which contribute to increasing the thermal resistance and survival of Salmonella. This study evaluated the long-term kinetics of Salmonella survival on different peanut products under storage at 28°C for 420 days. Samples of raw in-shell peanuts (aw = 0.29), roasted peanuts (aw = 0.39), unblanched peanut kernel (aw = 0.54), peanut brittle (aw = 0.30), paçoca (aw = 0.40) and pé-de-moça (aw = 0.68) were inoculated with Salmonella Typhimurium ATCC 14028 at two inoculum levels (3 and 6 log cfu/ g). The Salmonella behavior was influenced (p<0.05) by aw, lipid, carbohydrate and protein content. In most cases for both inoculum levels, the greatest reductions were seen after the first two weeks of storage, followed by a slower decline phase. The lowest reductions were verified in paçoca and roasted peanuts, with counts of 1.01 and 0.87 log cfu/ g at low inoculum level and 2.53 and 3.82 log cfu/ g at high inoculum level at the end of the storage time. The highest loss of viability was observed in pé-de-moça, with absence of Salmonella in 10-g after 180 days at low inoculum level. The Weibull model provided a suitable fit to the data (R2≥0.81), with δ value ranging from 0.06 to 49.75 days. Therefore, the results demonstrated that Salmonella survives longer in peanut products, beyond the shelf life (>420 days), especially in products with aw around 0.40.
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Affiliation(s)
- Maristela S. Nascimento
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, Brazil
| | - Joyce A. Carminati
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, Brazil
| | - Karen N. Morishita
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, Brazil
| | - Dionísio P. Amorim Neto
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, Brazil
| | | | - Rafael P. Maia
- Department of Statistics, University of Campinas, Campinas, Brazil
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Osaili T, Al-Nabulsi A, Nazzal D, Shaker R. Effect of storage temperatures and stresses on the survival ofSalmonellaspp. in halva. Lett Appl Microbiol 2017; 65:403-409. [DOI: 10.1111/lam.12791] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 07/27/2017] [Accepted: 07/27/2017] [Indexed: 11/29/2022]
Affiliation(s)
- T.M. Osaili
- Department of Clinical Nutrition and Dietetics; College of Health Sciences; University of Sharjah; Sharjah UAE
- Research Institute of Medical and Health Sciences; University of Sharjah; Sharjah UAE
- Department of Nutrition and Food Technology; Faculty of Agriculture; Jordan University of Science and Technology; Irbid 22110 Jordan
- Department of Nutrition and Food Technology; Faculty of Agriculture; Jordan University of Science and Technology; Irbid 22110 Jordan
| | - A.A. Al-Nabulsi
- Department of Nutrition and Food Technology; Faculty of Agriculture; Jordan University of Science and Technology; Irbid 22110 Jordan
| | - D.S. Nazzal
- Department of Nutrition and Food Technology; Faculty of Agriculture; Jordan University of Science and Technology; Irbid 22110 Jordan
| | - R.R. Shaker
- Department of Clinical Nutrition and Dietetics; College of Health Sciences; University of Sharjah; Sharjah UAE
- Research Institute of Medical and Health Sciences; University of Sharjah; Sharjah UAE
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45
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Wright DG, Minarsich J, Daeschel MA, Waite‐Cusic J. Thermal inactivation of
Salmonella
spp. in commercial tree nut and peanut butters in finished packaging. J Food Saf 2017. [DOI: 10.1111/jfs.12371] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Daniel G. Wright
- Department of Food Science and TechnologyOregon State UniversityCorvallis Oregon
| | - Joseph Minarsich
- Department of Food Science and TechnologyOregon State UniversityCorvallis Oregon
| | - Mark A. Daeschel
- Department of Food Science and TechnologyOregon State UniversityCorvallis Oregon
| | - Joy Waite‐Cusic
- Department of Food Science and TechnologyOregon State UniversityCorvallis Oregon
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Acosta O, Usaga J, Churey JJ, Worobo RW, Padilla-Zakour OI. Effect of Water Activity on the Thermal Tolerance and Survival of Salmonella enterica Serovars Tennessee and Senftenberg in Goat's Milk Caramel. J Food Prot 2017; 80:922-927. [PMID: 28459616 DOI: 10.4315/0362-028x.jfp-16-191] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The low thermal tolerance of Salmonella enterica in foods with intermediate moisture levels, such as caramel sauces, ensures that mild heat treatment is sufficient to achieve 5-log reductions of this pathogen. This treatment mitigates the risk posed by salmonellae in raw materials; however, recontamination might occur because of survival of the pathogen in products that are not heated before consumption. This study was conducted to evaluate the effect of water activity (aw) on the thermal tolerance and survival of S. enterica serovars Tennessee and Senftenberg. The D-values at 76, 78, and 80°C, z-values, and survival at 20.0 ± 0.5°C for 32 weeks of these two serovars were determined in goat's milk caramel at three aw values (0.85, 0.90, and 0.93). The highest thermal tolerance was observed at aw = 0.85 for Salmonella Senftenberg (D76°C = 2.9 ± 0.3 min), and the lowest was at aw = 0.93 for Salmonella Tennessee (D80°C = 0.131 ± 0.007 min). After a logarithmic transformation of the z-values, a significant interaction between serovar and aw was found (P < 0.0001), but no consistent trends were observed at the three evaluated aw levels for either serovar. Survival response was modeled using two sigmoidal three-parameter models. A significant interaction was found between nominal variables aw and serovar when comparing inflection points of the resulting curves: P < 0.0016 for the logistic model (R2 = 0.91) and P < 0.0014 for the Gompertz model (R2 = 0.92). Although a >8-log reduction was observed at week 20 of storage, regardless of the product's aw and the serovar, low levels of salmonellae were found in the product up to week 32 of storage. Our findings may assist the food industry with the establishment of critical limits for the safe thermal treatment of milk- and sugar-based foods with intermediate moisture levels. The survival data presented here highlight the relevance of implementing and effectively maintaining good sanitation and hygiene practices during the production of goat's milk caramel and similar food products.
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Affiliation(s)
- Oscar Acosta
- Department of Food Science, New York State Agricultural Experiment Station, Cornell University, 630 West North Street, Geneva, New York 14456, USA
| | - Jessie Usaga
- Department of Food Science, New York State Agricultural Experiment Station, Cornell University, 630 West North Street, Geneva, New York 14456, USA
| | - John J Churey
- Department of Food Science, New York State Agricultural Experiment Station, Cornell University, 630 West North Street, Geneva, New York 14456, USA
| | - Randy W Worobo
- Department of Food Science, New York State Agricultural Experiment Station, Cornell University, 630 West North Street, Geneva, New York 14456, USA
| | - Olga I Padilla-Zakour
- Department of Food Science, New York State Agricultural Experiment Station, Cornell University, 630 West North Street, Geneva, New York 14456, USA
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Farakos SMS, Pouillot R, Keller SE. Salmonella Survival Kinetics on Pecans, Hazelnuts, and Pine Nuts at Various Water Activities and Temperatures. J Food Prot 2017; 80:879-885. [PMID: 28414256 DOI: 10.4315/0362-028x.jfp-16-392] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The impact of temperature, water activity (aw), and nut composition on Salmonella survival on tree nuts has not been thoroughly examined. The aim of this study was to determine the effect of temperature, aw, and nut composition on the survival of Salmonella on tree nuts and develop predictive models. Pecans, hazelnuts, and pine nuts were chosen based on differences in their typical fat content. Nuts were inoculated with a cocktail of five Salmonella serotypes (11 log CFU/mL) and then were dried and stored at 4, 10, and 25°C at 0.41 ± 0.06 and 0.60 ± 0.05 aw for 1 year. Ten-gram quantities were removed at different intervals up to 364 days to test for surviving Salmonella populations (plating on selective and nonselective media) and aw. Experiments were carried out in triplicate. Salmonella populations were relatively stable over a year at 4 and 10°C at both aw levels with <1.5-log CFU/g decline. The best predictive model to describe Salmonella survival at 4 and 10°C was a log-linear model with a D-value for each tree nut and aw combination. Significant declines in Salmonella levels were observed at 25°C, where the best fit was a Weibull model with a fixed ρ for all tree nuts (ρ = 0.86), a δ value for each tree nut and aw combination, and a random factor to account for variability among replicates. The time for the first log reduction at 25°C and 0.37 ± 0.009 aw was estimated at 24 ± 2 weeks for hazelnuts, 34 ± 3 weeks for pecans, and 52 ± 7 weeks for pine nuts. At the same temperature, but with 0.54 ± 0.009 aw, the mean estimated time for the first log reduction decreased to 9 ± 1 weeks for hazelnuts, 10 ± 1 weeks for pecans, and 16 ± 1 weeks for pine nuts. Tree nut, aw, and temperature were shown to have a statistically significant effect on survival ( P < 0.05). No apparent influence of fat content on survival was observed. The results of this study can be used to predict changes in Salmonella levels on pecans, hazelnuts, and pine nuts after storage at the different temperatures and aw values.
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Affiliation(s)
- Sofia M Santillana Farakos
- 1 U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, College Park, Maryland 20740; and
| | - Régis Pouillot
- 1 U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, College Park, Maryland 20740; and
| | - Susanne E Keller
- 2 U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, Bedford Park, Illinois 60501, USA
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49
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Hokunan H, Koyama K, Hasegawa M, Kawamura S, Koseki S. Survival Kinetics of Salmonella enterica and Enterohemorrhagic Escherichia coli on a Plastic Surface at Low Relative Humidity and on Low-Water Activity Foods. J Food Prot 2016; 79:1680-1692. [PMID: 28221855 DOI: 10.4315/0362-028x.jfp-16-081] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We investigated the survival kinetics of Salmonella enterica and enterohemorrhagic Escherichia coli under various water activity (aw) conditions to elucidate the net effect of aw on pathogen survival kinetics and to pursue the development of a predictive model of pathogen survival as a function of aw. Four serotypes of S. enterica (Stanley, Typhimurium, Chester, and Oranienburg) and three serotypes of enterohemorrhagic E. coli ( E. coli O26, E. coli O111, and E. coli O157:H7) were examined. These bacterial strains were inoculated on a plastic plate surface at a constant relative humidity (RH) (22, 43, 58, 68, or 93% RH, corresponding to the aw) or on a surface of almond kernels (aw 0.58), chocolate (aw 0.43), radish sprout seeds (aw 0.58), or Cheddar cheese (aw 0.93) at 5, 15, or 25°C for up to 11 months. Under most conditions, the survival kinetics were nonlinear with tailing regardless of the storage aw, temperature, and bacterial strain. For all bacterial serotypes, there were no apparent differences in pathogen survival kinetics on the plastic surface at a given storage temperature among the tested RH conditions, except for the 93% RH condition. Most bacterial serotypes were rapidly inactivated on Cheddar cheese when stored at 5°C compared with their inactivation on chocolate, almonds, and radish sprout seeds. Distinct trends in bacterial survival kinetics were also observed between almond kernels and radish sprout seeds, even though the aws of these two foods were not significantly different. The survival kinetics of bacteria inoculated on the plastic plate surface showed little correspondence to those of bacteria inoculated on food matrices at an identical aw. Thus, these results demonstrated that, for low-aw foods and/or environments, aw alone is insufficient to account for the survival kinetics of S. enterica and enterohemorrhagic E. coli .
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Affiliation(s)
- Hidekazu Hokunan
- Graduate School of Agricultural Sciences, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan
| | - Kento Koyama
- Graduate School of Agricultural Sciences, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan
| | - Mayumi Hasegawa
- Graduate School of Agricultural Sciences, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan
| | - Shuso Kawamura
- Graduate School of Agricultural Sciences, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan
| | - Shigenobu Koseki
- Graduate School of Agricultural Sciences, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan
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50
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Carminati JDA, Amorim Neto DP, Morishita KN, Takano LV, Olivier Bernardi A, Copetti MV, do Nascimento MDS. Microbiological contamination in peanut confectionery processing plants. J Appl Microbiol 2016; 121:1071-8. [PMID: 27427217 DOI: 10.1111/jam.13235] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 07/06/2016] [Accepted: 07/14/2016] [Indexed: 10/21/2022]
Abstract
AIMS In order to investigate Enterobacteriaceae, coliforms, Escherichia coli and Salmonella contamination, a survey was conducted at three peanut confectionery processing companies (A, B and C) in Brazil. METHODS AND RESULTS Samples of different peanut confectionery products (n = 59), peanut raw material (n = 30), manufacturing environment (n = 116) and workers' hand surfaces (n = 12) were analysed. Salmonella and E. coli were not detected in any final product or raw material analysed. Enterobacteriaceae was isolated from 15% of final products. Coliforms were detected in only one sample. Referring to the raw material, six samples showed contamination by Enterobacteriaceae and three samples by coliforms. For the process environment, 19% and 11% of samples presented Enterobacteriaceae and coliforms. Escherichia coli was detected in 5% of samples, and one of these samples tested positive for Salmonella; this strain was serotyping as S. Heidelberg. All food handlers surveyed in Company C showed Enterobacteriaceae and coliforms on their hands. Escherichia coli was isolated from one food worker's hand. CONCLUSION The results showed that the manufacturing environment, including food handlers were considered the main sources for possible contamination of peanut confectionery products. SIGNIFICANCE AND IMPACT OF THE STUDY This has been the first study to investigate the occurrence of Salmonella and other Enterobacteriaceae throughout peanut confectionery processing lines. The results might be used to assist risk assessment studies and to establish more effective control measures.
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Affiliation(s)
- J de A Carminati
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - D P Amorim Neto
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - K N Morishita
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - L V Takano
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, SP, Brazil
| | - A Olivier Bernardi
- Department of Food Technology and Science, Federal University of Santa Maria, Santa Maria, RS, Brazil
| | - M V Copetti
- Department of Food Technology and Science, Federal University of Santa Maria, Santa Maria, RS, Brazil
| | - M da S do Nascimento
- Department of Food Technology, School of Food Engineering, University of Campinas, Campinas, SP, Brazil.
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