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An JH, Lee HS. Effect of the storage temperature on the quality of eggs inoculated with Salmonella Enteritidis onto shell. Food Sci Biotechnol 2024; 33:1255-1260. [PMID: 38440673 PMCID: PMC10908673 DOI: 10.1007/s10068-023-01402-1] [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: 04/24/2023] [Revised: 07/10/2023] [Accepted: 07/24/2023] [Indexed: 03/06/2024] Open
Abstract
This study explored the temperature-dependent effect on the growth characteristics of Salmonella Enteritidis (SE) on eggshell toward identifying an appropriate storage temperature for unwashed eggs in an actual distribution environment. Among the test storage temperatures (10 °C, 25 °C, and 35 °C), 25 °C was determined to be an appropriate storage temperature, with no effect of changing temperature on the control of SE on eggshell. Regarding the effect of the temperature on egg quality, the quality indicators of egg such as Haugh unit, yolk index, albumin index, and albumin pH were significantly maintained. These results indicated that unwashed eggs should be distributed at 25 °C for SE control, and the storage temperature should be below 10 °C from at least day 4 onward after the start of distribution to maintain egg quality. This study will assist for safety management of unwashed egg in an actual distribution environment.
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Affiliation(s)
- Ji-Hoon An
- Department of Food Safety and Regulatory Science, Chung-Ang University, Anseong, 17546 Republic of Korea
| | - Hee-Seok Lee
- Department of Food Safety and Regulatory Science, Chung-Ang University, Anseong, 17546 Republic of Korea
- Department of Food Science and Biotechnology, Chung-Ang University, Anseong, 17546 Republic of Korea
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2
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Guan S, Jiang R, Chen DY, Michael A, Meng C, Biswal B. Multifractal long-range dependence pattern of functional magnetic resonance imaging in the human brain at rest. Cereb Cortex 2023; 33:11594-11608. [PMID: 37851793 DOI: 10.1093/cercor/bhad393] [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: 09/12/2023] [Revised: 10/01/2023] [Accepted: 10/02/2023] [Indexed: 10/20/2023] Open
Abstract
Long-range dependence is a prevalent phenomenon in various biological systems that characterizes the long-memory effect of temporal fluctuations. While recent research suggests that functional magnetic resonance imaging signal has fractal property, it remains unknown about the multifractal long-range dependence pattern of resting-state functional magnetic resonance imaging signals. The current study adopted the multifractal detrended fluctuation analysis on highly sampled resting-state functional magnetic resonance imaging scans to investigate long-range dependence profile associated with the whole-brain voxels as specific functional networks. Our findings revealed the long-range dependence's multifractal properties. Moreover, long-term persistent fluctuations are found for all stations with stronger persistency in whole-brain regions. Subsets with large fluctuations contribute more to the multifractal spectrum in the whole brain. Additionally, we found that the preprocessing with band-pass filtering provided significantly higher reliability for estimating long-range dependence. Our validation analysis confirmed that the optimal pipeline of long-range dependence analysis should include band-pass filtering and removal of daily temporal dependence. Furthermore, multifractal long-range dependence characteristics in healthy control and schizophrenia are different significantly. This work has provided an analytical pipeline for the multifractal long-range dependence in the resting-state functional magnetic resonance imaging signal. The findings suggest differential long-memory effects in the intrinsic functional networks, which may offer a neural marker finding for understanding brain function and pathology.
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Affiliation(s)
- Sihai Guan
- College of Electronic and Information, Southwest Minzu University, Chengdu 610041, China
- Key Laboratory of Electronic and Information Engineering, State Ethnic Affairs Commission, Chengdu 610041, China
| | - Runzhou Jiang
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 611731, China
- Medical Equipment Department, Xiangyang No.1 People's Hospital, Xiangyang 441000, China
| | - Donna Y Chen
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, United States
| | - Andrew Michael
- Duke Institute for Brain Sciences, Duke University, Durham, NC 27708, United States
| | - Chun Meng
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 611731, China
| | - Bharat Biswal
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 611731, China
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, United States
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3
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Bolívar A, Garrote Achou C, Tarlak F, Cantalejo MJ, Costa JCCP, Pérez-Rodríguez F. Modeling the Growth of Six Listeria monocytogenes Strains in Smoked Salmon Pâté. Foods 2023; 12:foods12061123. [PMID: 36981050 PMCID: PMC10048639 DOI: 10.3390/foods12061123] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 02/23/2023] [Accepted: 02/28/2023] [Indexed: 03/30/2023] Open
Abstract
In this study, the growth of six L. monocytogenes strains isolated from different fish products was quantified and modeled in smoked salmon pâté at a temperature ranging from 2 to 20 °C. The experimental data obtained for each strain was fitted to the primary growth model of Baranyi and Roberts to estimate the following kinetic parameters: lag phase (λ), maximum specific growth rate (μmax), and maximum cell density (Nmax). Then, the effect of storage temperature on the obtained μmax values was modeled by the Ratkowsky secondary model. In general, the six L. monocytogenes strains showed rapid growth in salmon pâté at all storage temperatures, with a relatively short lag phase λ, even at 2 °C. The growth behavior among the tested strains was similar at the same storage temperature, although significant differences were found for the parameters λ and μmax. Besides, the growth variations among the strains did not follow a regular pattern. The estimated secondary model parameter Tmin ranged from -4.25 to -3.19 °C. This study provides accurate predictive models for the growth of L. monocytogenes in fish pâtés that can be used in shelf life and microbial risk assessment studies. In addition, the models generated in this work can be implemented in predictive modeling tools and repositories that can be reliably and easily used by the fish industry and end-users to establish measures aimed at controlling the growth of L. monocytogenes in fish-based pâtés.
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Affiliation(s)
- Araceli Bolívar
- Department of Food Science and Technology, UIC Zoonosis y Enfermedades Emergentes ENZOEM, ceiA3, Universidad de Córdoba, 14014 Córdoba, Spain
| | - Chajira Garrote Achou
- Department of Agronomy, Biotechnology and Food, School of Agriculture Engineering, Public University of Navarre (UPNA), Campus de Arrosadia, 31006 Pamplona, Spain
| | - Fatih Tarlak
- Department of Nutrition and Dietetics, Istanbul Gedik University, 34876 Istanbul, Turkey
| | - María Jesús Cantalejo
- Department of Agronomy, Biotechnology and Food, School of Agriculture Engineering, Public University of Navarre (UPNA), Campus de Arrosadia, 31006 Pamplona, Spain
| | - Jean Carlos Correia Peres Costa
- Department of Food Science and Technology, UIC Zoonosis y Enfermedades Emergentes ENZOEM, ceiA3, Universidad de Córdoba, 14014 Córdoba, Spain
| | - Fernando Pérez-Rodríguez
- Department of Food Science and Technology, UIC Zoonosis y Enfermedades Emergentes ENZOEM, ceiA3, Universidad de Córdoba, 14014 Córdoba, Spain
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4
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Chitra M, Sutha S, Pappa N. Application of deep neural techniques in predictive modelling for the estimation of Escherichia coli growth rate. J Appl Microbiol 2020; 130:1645-1655. [PMID: 33064920 DOI: 10.1111/jam.14901] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 10/01/2020] [Accepted: 10/12/2020] [Indexed: 11/27/2022]
Abstract
AIMS To develop a predictive model for Escherichia coli using deep neural networks. METHODS AND RESULTS Batch experiments are conducted at different temperatures closer to optimum value (36·5°C, 37°C, 37·5°C, 38°C and 38·5°C) to obtain the growth curves of E .coli K-12. Two primary models namely modified Gompertz and new logistic are chosen. Three secondary models namely Gaussian, nonlinear autoregressive eXogenous (NARX) model and long short-term memory (LSTM) are developed. The novelty in this paper is the development of secondary models using artificial neural network (ANN) and deep network. The performance measures chosen to compare the developed primary and secondary models are correlation coefficient (R2 ), root-mean-square error (RMSE) and accuracy factor (Af ). Results show that modified Gompertz model has better R2 (0·99) and RMSE (0·019) when compared to new logistic model. Also, the deep network model outperforms other secondary models. Based on the primary and novel secondary model, a predictive model (tertiary model) is developed with improved accuracy and is validated. CONCLUSIONS The proposed predictive model exhibit good validation results in terms of RMSE and R2 values and can be applied for determining the growth rate of E. coli at a particular temperature value. SIGNIFICANCE AND IMPACT OF THE STUDY The proposed model can be used in food processing industries during enzyme production such as Chymosin, to predict the growth rate of E. coli as a function of temperature. Also, the developed LSTM and NARX models can be used to predict maximum specific growth rate of other microbial strains with proper training.
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Affiliation(s)
- M Chitra
- Department of Instrumentation Engineering, Madras Institute of Technology (MIT) Campus, Anna University, Chennai, India
| | - S Sutha
- Department of Instrumentation Engineering, Madras Institute of Technology (MIT) Campus, Anna University, Chennai, India
| | - N Pappa
- Department of Instrumentation Engineering, Madras Institute of Technology (MIT) Campus, Anna University, Chennai, India
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5
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Development of a general model to describe Salmonella spp. growth in chicken meat subjected to different temperature profiles. Food Control 2020. [DOI: 10.1016/j.foodcont.2020.107151] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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6
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Ranucci D, Roila R, Andoni E, Braconi P, Branciari R. Punica granatum and Citrus spp. Extract Mix Affects Spoilage Microorganisms Growth Rate in Vacuum-Packaged Cooked Sausages Made from Pork Meat, Emmer Wheat ( Triticum dicoccum Schübler), Almond ( Prunus dulcis Mill.) and Hazelnut ( Corylus avellana L.). Foods 2019; 8:foods8120664. [PMID: 31835622 PMCID: PMC6963912 DOI: 10.3390/foods8120664] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 11/28/2019] [Accepted: 12/09/2019] [Indexed: 01/01/2023] Open
Abstract
Sausage made from pork meat, emmer wheat (Triticum dicoccum Schübler), almond (Prunus dulcis Mill.), and hazelnut (Corylus avellana L.) was integrated with a mix of Punica granatum and Citrus spp. extracts to evaluate the possible effects on the growth and oxidation of spoilage microorganisms. Two concentrations of the mix were added, respectively, during sausage-making, and the final products were compared with a control group, without the extract mix, during storage. The use of the mix, especially at 10 g/1000 g of the whole ingredients, delayed the pH drop and thiobarbituric acid-reactive substances (TBARs) value during storage. Total viable count, lactic acid bacteria and psychrotrophic microbial counts were also affected, as the extract mix lowered the maximum growth rate of the microbial population considered. The sensory analyses revealed an improvement in the shelf-life of 6 and 16 days, respectively, when 5‰ and 10‰ of the mix were used.
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Affiliation(s)
- David Ranucci
- Centro Interuniversitario per l’Ambiente (CIPLA), University of Perugia, Via Enrico dal Pozzo, 06123 Perugia, Italy; (D.R.); (P.B.)
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, Italy;
| | - Rossana Roila
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, Italy;
| | - Egon Andoni
- Faculty of Veterinary Medicine, Universiteti Bujqësor i Tiranës, Kodër Kamëz, SH1, 1000 Tiranë, Albania;
| | - Paolo Braconi
- Centro Interuniversitario per l’Ambiente (CIPLA), University of Perugia, Via Enrico dal Pozzo, 06123 Perugia, Italy; (D.R.); (P.B.)
| | - Raffaella Branciari
- Centro Interuniversitario per l’Ambiente (CIPLA), University of Perugia, Via Enrico dal Pozzo, 06123 Perugia, Italy; (D.R.); (P.B.)
- Department of Veterinary Medicine, University of Perugia, Via San Costanzo 4, 06126 Perugia, Italy;
- Correspondence:
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7
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Thomas M, Tiwari R, Mishra A. Predictive Model of Listeria monocytogenes Growth in Queso Fresco. J Food Prot 2019; 82:2071-2079. [PMID: 31714806 DOI: 10.4315/0362-028x.jfp-19-185] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Listeria monocytogenes is a hardy psychrotrophic pathogen that has been linked to several cheese-related outbreaks in the United States, including a recent outbreak in which a fresh cheese (queso fresco) was implicated. The purpose of this study was to develop primary, secondary, and tertiary predictive models for the growth of L. monocytogenes in queso fresco and to validate these models using nonisothermal time and temperature profiles. A mixture of five strains of L. monocytogenes was used to inoculate pasteurized whole milk to prepare queso fresco. Ten grams of each fresh cheese sample was vacuum packaged and stored at 4, 10, 15, 20, 25, and 30°C. From samples at each storage temperature, subsamples were removed at various times and diluted in 0.1% peptone water, and bacteria were enumerated on Listeria selective agar. Growth data from each temperature were fitted using the Baranyi model as the primary model and the Ratkowsky model as the secondary model. Models were then validated using nonisothermal conditions. The Baranyi model was fitted to the isothermal growth data with acceptable goodness of fit statistics (R2 = 0.928; root mean square error = 0.317). The Ratkowsky square root model was fitted to the specific growth rates at different temperatures (R2 = 0.975). The tertiary model developed from these models was validated using the growth data with two nonisothermal time and temperature profiles (4 to 20°C for 19 days and 15 to 30°C for 11 days). Data for these two profiles were compared with the model prediction using an acceptable prediction zone analysis; >70% of the growth observations were within the acceptable prediction zone (between -1.0 and 0.5 log CFU/g). The model developed in this study will be useful for estimating the growth of L. monocytogenes in queso fresco. These predictions will help in estimation of the risk of listeriosis from queso fresco under extended storage and temperature abuse conditions.
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Affiliation(s)
- Merlyn Thomas
- Department of Food Science and Technology, University of Georgia, 100 Cedar Street, Athens, Georgia 30602
| | - Ratnesh Tiwari
- Department of Mechanical Engineering, University of Maryland, College Park, Maryland 20742, USA
| | - Abhinav Mishra
- Department of Food Science and Technology, University of Georgia, 100 Cedar Street, Athens, Georgia 30602
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8
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Noviyanti F, Hosotani Y, Koseki S, Inatsu Y, Kawasaki S. Predictive Modeling for the Growth ofSalmonellaEnteritidis in Chicken Juice by Real-Time Polymerase Chain Reaction. Foodborne Pathog Dis 2018; 15:406-412. [DOI: 10.1089/fpd.2017.2392] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Fia Noviyanti
- Tsukuba Life Science Innovation, University of Tsukuba, Tsukuba, Japan
| | - Yukie Hosotani
- Division of Food Safety Research, Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Japan
| | - Shigenobu Koseki
- Research Faculty of Agriculture, Hokkaido University, Hokkaido, Japan
| | - Yasuhiro Inatsu
- Division of Food Safety Research, Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Japan
| | - Susumu Kawasaki
- Tsukuba Life Science Innovation, University of Tsukuba, Tsukuba, Japan
- Division of Food Safety Research, Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Japan
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9
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Effect of storage conditions in the response of Listeria monocytogenes in a fresh purple vegetable smoothie compared with an acidified TSB medium. Food Microbiol 2018; 72:98-105. [DOI: 10.1016/j.fm.2017.11.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 10/29/2017] [Accepted: 11/11/2017] [Indexed: 11/23/2022]
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10
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Aldars-García L, Marín S, Sanchis V, Magan N, Medina A. Assessment of intraspecies variability in fungal growth initiation of Aspergillus flavus and aflatoxin B 1 production under static and changing temperature levels using different initial conidial inoculum levels. Int J Food Microbiol 2018; 272:1-11. [PMID: 29482078 DOI: 10.1016/j.ijfoodmicro.2018.02.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 01/06/2018] [Accepted: 02/11/2018] [Indexed: 11/24/2022]
Abstract
Intraspecies variability in fungal growth and mycotoxin production has important implications for food safety. Using the Bioscreen C we have examined spectrophotometrically intraspecies variability of A. flavus using 10 isolates under different environments, including temperature shifts, in terms of growth and aflatoxin B1 (AFB1) production. Five high and five low AFB1 producers were examined. The study was conducted at 5 isothermal conditions (from 15 to 37 °C) and 4 dynamic scenarios (between 15 and 30 °C). The experiments were carried out in a semisolid YES medium at 0.92 aw and two inoculum levels, 102 and 103 spores/mL. The Time to Detection (TTD) of growth initiation was determined and modelled as a function of temperature through a polynomial equation and the model was used to predict TTD under temperature upshifts conditions using a novel approach. The results obtained in this study have shown that a model can be developed to describe the effect of temperature upshifts on the TTD for all the studied isolates and inoculum levels. Isolate variability increased as the growth conditions became more stressful and with a lower inoculum level. Inoculum level affected the intraspecies variability but not the repeatability of the experiments. In dynamic conditions, isolate responses depended both on the temperature shift and, predominantly, the final temperature level. AFB1 production was highly variable among the isolates and greatly depended on temperature (optimum temperature at 30-35 °C) and inoculum levels, with often higher production with lower inoculum. This suggests that, from an ecological point of view, the potential isolate variability and interaction with dynamic conditions should be taken into account in developing strategies to control growth and predicting mycotoxin risks by mycotoxigenic fungi.
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Affiliation(s)
- Laila Aldars-García
- Food Technology Dept, XaRTA-UTPV, Agrotecnio Center, University of Lleida, Spain.
| | - Sonia Marín
- Food Technology Dept, XaRTA-UTPV, Agrotecnio Center, University of Lleida, Spain.
| | - Vicente Sanchis
- Food Technology Dept, XaRTA-UTPV, Agrotecnio Center, University of Lleida, Spain.
| | - Naresh Magan
- Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Bedford MK43 0AL, UK.
| | - Angel Medina
- Applied Mycology Group, Environment and AgriFood Theme, Cranfield University, Cranfield, Bedford MK43 0AL, UK.
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11
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Salazar JK, Sahu SN, Hildebrandt IM, Zhang L, Qi Y, Liggans G, Datta AR, Tortorello ML. Growth Kinetics of Listeria monocytogenes in Cut Produce. J Food Prot 2017; 80:1328-1336. [PMID: 28708030 DOI: 10.4315/0362-028x.jfp-16-516] [Citation(s) in RCA: 35] [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
Cut produce continues to constitute a significant portion of the fresh fruit and vegetables sold directly to consumers. As such, the safety of these items during storage, handling, and display remains a concern. Cut tomatoes, cut leafy greens, and cut melons, which have been studied in relation to their ability to support pathogen growth, have been specifically identified as needing temperature control for safety. Data are needed on the growth behavior of foodborne pathogens in other types of cut produce items that are commonly offered for retail purchase and are potentially held without temperature control. This study assessed the survival and growth of Listeria monocytogenes in cut produce items that are commonly offered for retail purchase, specifically broccoli, green and red bell peppers, yellow onions, canned green and black olives, fresh green olives, cantaloupe flesh and rind, avocado pulp, cucumbers, and button mushrooms. The survival of L. monocytogenes strains representing serotypes 1/2a, 1/2b, and 4b was determined on the cut produce items for each strain individually at 5, 10, and 25°C for up to 720 h. The modified Baranyi model was used to determine the growth kinetics (the maximum growth rates and maximum population increases) in the L. monocytogenes populations. The products that supported the most rapid growth of L. monocytogenes, considering the fastest growth and resulting population levels, were cantaloupe flesh and avocado pulp. When stored at 25°C, the maximum growth rates for these products were 0.093 to 0.138 log CFU/g/h and 0.130 to 0.193 log CFU/g/h, respectively, depending on the strain. Green olives and broccoli did not support growth at any temperature. These results can be used to inform discussions surrounding whether specific time and temperature storage conditions should be recommended for additional cut produce items.
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Affiliation(s)
- Joelle K Salazar
- 1 U.S. Food and Drug Administration, Division of Food Processing Science and Technology, Office of Food Safety, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Surasri N Sahu
- 3 Illinois Institute of Technology, Institute for Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501; and
| | - Ian M Hildebrandt
- 1 U.S. Food and Drug Administration, Division of Food Processing Science and Technology, Office of Food Safety, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Lijie Zhang
- 2 U.S. Food and Drug Administration, Division of Virulence Assessment, Office of Applied Research and Safety Assessment, 8301 Muirkirk Road, Laurel, Maryland 20708
| | - Yan Qi
- 2 U.S. Food and Drug Administration, Division of Virulence Assessment, Office of Applied Research and Safety Assessment, 8301 Muirkirk Road, Laurel, Maryland 20708
| | - Girvin Liggans
- 4 U.S. Food and Drug Administration, Retail Food Protection Staff, Office of Food Safety, 5001 Campus Drive, College Park, Maryland 20740, USA
| | - Atin R Datta
- 3 Illinois Institute of Technology, Institute for Food Safety and Health, 6502 South Archer Road, Bedford Park, Illinois 60501; and
| | - Mary Lou Tortorello
- 1 U.S. Food and Drug Administration, Division of Food Processing Science and Technology, Office of Food Safety, 6502 South Archer Road, Bedford Park, Illinois 60501
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12
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Sutton AO, Strickland D, Norris DR. Food storage in a changing world: implications of climate change for food-caching species. ACTA ACUST UNITED AC 2016. [DOI: 10.1186/s40665-016-0025-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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13
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Galarz LA, Fonseca GG, Prentice C. Predicting bacterial growth in raw, salted, and cooked chicken breast fillets during storage. FOOD SCI TECHNOL INT 2016; 22:461-74. [DOI: 10.1177/1082013215618519] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 10/19/2015] [Indexed: 11/15/2022]
Abstract
Growth curves were evaluated for aerobic mesophilic and psychrotrophic bacteria, Pseudomonas spp. and Staphylococcus spp., grown in raw, salted, and cooked chicken breast at 2, 4, 7, 10, 15, and 20 ℃, respectively, using the modified Gompertz and modified logistic models. Shelf life was determined based on microbiological counts and sensory analysis. Temperature increase reduced the shelf life, which varied from 10 to 26 days at 2 ℃, from nine to 21 days at 4 ℃, from six to 12 days at 7 ℃, from four to eight days at 10 ℃, from two to four days at 15 ℃, and from one to two days at 20 ℃. In most cases, cooked chicken breast showed the highest microbial count, followed by raw breast and lastly salted breast. The data obtained here were useful for the generation of mathematical models and parameters. The models presented high correlation and can be used for predictive purposes in the poultry meat supply chain.
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Affiliation(s)
- Liane Aldrighi Galarz
- Laboratory of Food Technology, School of Chemistry and Food, Federal University of Rio Grande, Rio Grande, Brazil
| | - Gustavo Graciano Fonseca
- Laboratory of Bioengineering, Faculty of Biological and Environmental Sciences, Federal University of Grande Dourados, Dourados, Brazil
| | - Carlos Prentice
- Laboratory of Food Technology, School of Chemistry and Food, Federal University of Rio Grande, Rio Grande, Brazil
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14
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Lin H, Shavezipur M, Yousef A, Maleky F. Prediction of growth of Pseudomonas fluorescens in milk during storage under fluctuating temperature. J Dairy Sci 2016; 99:1822-1830. [DOI: 10.3168/jds.2015-10179] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 09/23/2015] [Indexed: 11/19/2022]
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15
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Giacometti F, Serraino A, Finazzi G, Daminelli P, Losio MN, Tamba M, Garigliani A, Mattioli R, Riu R, Zanoni RG. Field handling conditions of raw milk sold in vending machines: experimental evaluation of the behaviour ofListeria monocytogenes, Escherichia coliO157:H7,Salmonella TyphimuriumandCampylobacter jejuni. ITALIAN JOURNAL OF ANIMAL SCIENCE 2016. [DOI: 10.4081/ijas.2012.e24] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Wang X, Dong Q, Liu Y, Shi Y, Song X, Liu Q. Modeling Growth of Pseudomonas Aeruginosa
Single Cells with Temperature Shifts. J Food Saf 2016. [DOI: 10.1111/jfs.12258] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xin Wang
- School of Medical Instrument and Food Engineering; University of Shanghai for Science and Technology; Shanghai China
| | - Qingli Dong
- School of Medical Instrument and Food Engineering; University of Shanghai for Science and Technology; Shanghai China
| | - Yangtai Liu
- School of Medical Instrument and Food Engineering; University of Shanghai for Science and Technology; Shanghai China
| | - Yujiao Shi
- School of Medical Instrument and Food Engineering; University of Shanghai for Science and Technology; Shanghai China
| | - Xiaoyu Song
- China National Center for Food Safety Risk Assessment; Beijing China
| | - Qing Liu
- School of Medical Instrument and Food Engineering; University of Shanghai for Science and Technology; Shanghai China
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17
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An attempt to model the probability of growth and aflatoxin B1 production of Aspergillus flavus under non-isothermal conditions in pistachio nuts. Food Microbiol 2015; 51:117-29. [DOI: 10.1016/j.fm.2015.05.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 05/12/2015] [Accepted: 05/26/2015] [Indexed: 11/18/2022]
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Zhu S, Chen G. Numerical solution of a microbial growth model applied to dynamic environments. J Microbiol Methods 2015; 112:76-82. [DOI: 10.1016/j.mimet.2015.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 03/06/2015] [Accepted: 03/07/2015] [Indexed: 10/23/2022]
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Powell S, Ratkowsky D, Tamplin M. Predictive model for the growth of spoilage bacteria on modified atmosphere packaged Atlantic salmon produced in Australia. Food Microbiol 2015; 47:111-5. [DOI: 10.1016/j.fm.2014.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 11/25/2014] [Accepted: 12/01/2014] [Indexed: 10/24/2022]
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McConnell JA, Schaffner DW. Validation of mathematical models for Salmonella growth in raw ground beef under dynamic temperature conditions representing loss of refrigeration. J Food Prot 2014; 77:1110-5. [PMID: 24988016 DOI: 10.4315/0362-028x.jfp-14-038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Temperature is a primary factor in controlling the growth of microorganisms in food. The current U. S. Food and Drug Administration Model Food Code guidelines state that food can be kept out of temperature control for up to 4 h without qualifiers, or up to 6 h, if the food product starts at an initial 41 °F (5 °C) temperature and does not exceed 70 °F (21 °C) at 6 h. This project validates existing ComBase computer models for Salmonella growth under changing temperature conditions modeling scenarios using raw ground beef as a model system. A cocktail of Salmonella serovars isolated from different meat products ( Salmonella Copenhagen, Salmonella Montevideo, Salmonella Typhimurium, Salmonella Saintpaul, and Salmonella Heidelberg) was made rifampin resistant and used for all experiments. Inoculated samples were held in a programmable water bath at 4.4 °C (40 °F) and subjected to linear temperature changes to different final temperatures over various lengths of time and then returned to 4.4 °C (40 °F). Maximum temperatures reached were 15.6, 26.7, or 37.8 °C (60, 80, or 100 °F), and the temperature increases took place over 4, 6, and 8 h, with varying cooling times. Our experiments show that when maximum temperatures were lower (15.6 or 26.7 °C), there was generally good agreement between the ComBase models and experiments: when temperature increases of 15.6 or 26.7 °C occurred over 8 h, experimental data were within 0.13 log CFU of the model predictions. When maximum temperatures were 37 °C, predictive models were fail-safe. Overall bias of the models was 1.11. and accuracy was 2.11. Our experiments show the U.S. Food and Drug Administration Model Food Code guidelines for holding food out of temperature control are quite conservative. Our research also shows that the ComBase models for Salmonella growth are accurate or fail-safe for dynamic temperature conditions as might be observed due to power loss from natural disasters or during transport out of temperature control.
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Affiliation(s)
- Jennifer A McConnell
- Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, New Jersey 08901-8520, USA
| | - Donald W Schaffner
- Department of Food Science, Rutgers University, 65 Dudley Road, New Brunswick, New Jersey 08901-8520, USA. schaffner@aesop
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Kamana O, Ceuppens S, Jacxsens L, Kimonyo A, Uyttendaele M. Microbiological quality and safety assessment of the Rwandan milk and dairy chain. J Food Prot 2014; 77:299-307. [PMID: 24490925 DOI: 10.4315/0362-028x.jfp-13-230] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Milk is a valuable and nutritious food product that can partially fulfill the rising food demand of the growing African population. The microbiological status of milk and derived products was assessed throughout the milk and dairy chain in Rwanda by enumeration of the total mesophilic count, coliforms, and Staphylococcus aureus and detection of Salmonella and Listeria monocytogenes. The quality of raw milk was satisfactory for the majority of samples, but 5.2% contained Salmonella. At the processing level, the total mesophilic count and coliform numbers indicated ineffective heat treatment during pasteurization or postpasteurization contamination. Increasing bacterial counts were observed along the retail chain and could be attributed to insufficient temperature control during storage. Milk and dairy products sold in milk shops were of poor and variable microbiological quality in comparison with the pasteurized milk sold in supermarkets. In particular, the microbiological load and pathogen prevalence in cheese were unacceptably high.
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Affiliation(s)
- Olivier Kamana
- Ghent University, Faculty of Bioscience Engineering, Laboratory of Food Microbiology and Food Preservation (LFMFP), Ghent, Belgium; Higher Institute of Agriculture and Animal Husbandry, Faculty of Agriculture and Rural Development, Department of Animal Production, Busogo, Rwanda
| | - Siele Ceuppens
- Ghent University, Faculty of Bioscience Engineering, Laboratory of Food Microbiology and Food Preservation (LFMFP), Ghent, Belgium
| | - Liesbeth Jacxsens
- Ghent University, Faculty of Bioscience Engineering, Laboratory of Food Microbiology and Food Preservation (LFMFP), Ghent, Belgium
| | - Anastase Kimonyo
- Kigali Institute of Science and Technology, Faculty of Applied Sciences, Department of Food Science and Technology, Kigali, Rwanda
| | - Mieke Uyttendaele
- Ghent University, Faculty of Bioscience Engineering, Laboratory of Food Microbiology and Food Preservation (LFMFP), Ghent, Belgium.
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Gkogka E, Reij M, Gorris L, Zwietering M. Risk assessment strategies as a tool in the application of the Appropriate Level of Protection (ALOP) and Food Safety Objective (FSO) by risk managers. Int J Food Microbiol 2013; 167:8-28. [DOI: 10.1016/j.ijfoodmicro.2013.04.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 04/14/2013] [Accepted: 04/18/2013] [Indexed: 11/26/2022]
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Longhi DA, Dalcanton F, Aragão GMFD, Carciofi BAM, Laurindo JB. Assessing the prediction ability of different mathematical models for the growth of Lactobacillus plantarum under non-isothermal conditions. J Theor Biol 2013; 335:88-96. [DOI: 10.1016/j.jtbi.2013.06.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 06/20/2013] [Accepted: 06/21/2013] [Indexed: 11/26/2022]
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Mathematical Models for Microbial Kinetics in Solid-State Fermentation: A Review. IRANIAN JOURNAL OF BIOTECHNOLOGY 2013. [DOI: 10.5812/ijb.9426] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ivancic T, Jamnik P, Stopar D. Cold shock CspA and CspB protein production during periodic temperature cycling in Escherichia coli. BMC Res Notes 2013; 6:248. [PMID: 23815967 PMCID: PMC3704898 DOI: 10.1186/1756-0500-6-248] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2012] [Accepted: 06/25/2013] [Indexed: 11/30/2022] Open
Abstract
Background Temperature is an important environmental factor which can dramatically affect biochemical processes in bacteria. Temperatures above optimal cause heat shock, while low temperatures induce cold shock. Since the physiological response of the bacterium Escherichia coli to slow temperature fluctuation is not well known, we investigated the effect of periodic temperature cycling between 37° and 8°C with a period of 2 h on proteome profile, cold shock CspA and CspB protein and gene production. Results Several proteins (i.e. succinyl-CoA synthetase subunit alpha, periplasmic oligopeptide-binding protein, maltose-binding periplasmic protein, outer membrane porin protein, flavodoxin-1, phosphoserine aminotransferase) were up or down regulated during temperature cycling, in addition to CspA and CspB production. The results indicate that transcription of cspA and cspB increased during each temperature downshift and consistently decreased after each temperature upshift. In sharp contrast CspA-FLAG and CspB-FLAG protein concentrations in the cell increased during the first temperature down-shift and remained unresponsive to further temperature fluctuations. The proteins CspA-FLAG and CspB-FLAG were not significantly degraded during the temperature cycling. Conclusion The study demonstrated that slow periodic temperature cycling affected protein production compared to cells constantly incubated at 37°C or during classical cold shock. Bacterial cspA and cspB mRNA transcript levels fluctuated in synchrony with the temperature fluctuations. There was no corresponding pattern of CspA and CspB protein production during temperature cycling.
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Affiliation(s)
- Tina Ivancic
- Laboratory of Microbiology, Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, Večna Pot 111, 1000 Ljubljana, Slovenia
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Schaffner DW. Utilization of mathematical models to manage risk of holding cold food without temperature control. J Food Prot 2013; 76:1085-94. [PMID: 23726207 DOI: 10.4315/0362-028x.jfp-12-424] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This document describes the development of a tool to manage the risk of the transportation of cold food without temperature control. The tool uses predictions from ComBase predictor and builds on the 2009 U.S. Food and Drug Administration Model Food Code and supporting scientific data in the Food Code annex. I selected Salmonella spp. and Listeria monocytogenes as the organisms for risk management. Salmonella spp. were selected because they are associated with a wide variety of foods and grow rapidly at temperatures >17°C. L. monocytogenes was selected because it is frequently present in the food processing environment, it was used in the original analysis contained in the Food Code Annex, and it grows relatively rapidly at temperatures <17°C. The suitability of a variety of growth models under changing temperature conditions is largely supported by the published literature. The ComBase predictions under static temperature conditions were validated using 148 ComBase database observations for Salmonella spp. and L. monocytogenes in real foods. The times and temperature changes encompassed by ComBase Predictor models for Salmonella spp. and L. monocytogenes are consistent with published data on consumer food transport to the home from the grocery store and on representative foods from a wholesale cash and carry food service supplier collected as part of this project. The resulting model-based tool will be a useful aid to risk managers and customers of wholesale cash and carry food service suppliers, as well as to anyone interested in assessing and managing the risks posed by holding cold foods out of temperature control in supermarkets, delis, restaurants, cafeterias, and homes.
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Affiliation(s)
- Donald W Schaffner
- Food Science Department, Rutgers University, 65 Dudley Road, New Brunswick, New Jersey 08901, USA.
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Bruckner S, Albrecht A, Petersen B, Kreyenschmidt J. A predictive shelf life model as a tool for the improvement of quality management in pork and poultry chains. Food Control 2013. [DOI: 10.1016/j.foodcont.2012.05.048] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Giuffrida A, Valenti D, Giarratana F, Ziino G, Panebianco A. A new approach to modelling the shelf life of Gilthead seabream (Sparus aurata). Int J Food Sci Technol 2013. [DOI: 10.1111/ijfs.12082] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alessandro Giuffrida
- Department of Veterinary Science; University of Messina; Polo Universitario dell'Annunziata; 98168; Messina; Italy
| | - Davide Valenti
- Department of Physics; University of Palermo and CNISM (Università di Palermo) Group of Interdisciplinary Physics; V.le delle Scienze Ed. 18; 90128; Palermo; Italy
| | - Filippo Giarratana
- Department of Veterinary Science; University of Messina; Polo Universitario dell'Annunziata; 98168; Messina; Italy
| | - Graziella Ziino
- Department of Veterinary Science; University of Messina; Polo Universitario dell'Annunziata; 98168; Messina; Italy
| | - Antonio Panebianco
- Department of Veterinary Science; University of Messina; Polo Universitario dell'Annunziata; 98168; Messina; Italy
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Modelling of bacterial growth with shifts in temperature using automated methods with Listeria monocytogenes and Pseudomonas aeruginosa as examples. Int J Food Microbiol 2012; 155:29-35. [DOI: 10.1016/j.ijfoodmicro.2012.01.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 11/24/2011] [Accepted: 01/15/2012] [Indexed: 11/20/2022]
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Muñoz-Cuevas M, Metris A, Baranyi J. Predictive modelling of Salmonella: From cell cycle measurements to e-models. Food Res Int 2012. [DOI: 10.1016/j.foodres.2011.04.033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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31
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Pujol L, Kan-King-Yu D, Le Marc Y, Johnston MD, Rama-Heuzard F, Guillou S, McClure P, Membré JM. Establishing equivalence for microbial-growth-inhibitory effects ("iso-hurdle rules") by analyzing disparate listeria monocytogenes data with a gamma-type predictive model. Appl Environ Microbiol 2012; 78:1069-80. [PMID: 22156426 PMCID: PMC3273012 DOI: 10.1128/aem.06691-11] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 11/28/2011] [Indexed: 11/20/2022] Open
Abstract
Preservative factors act as hurdles against microorganisms by inhibiting their growth; these are essential control measures for particular food-borne pathogens. Different combinations of hurdles can be quantified and compared to each other in terms of their inhibitory effect ("iso-hurdle"). We present here a methodology for establishing microbial iso-hurdle rules in three steps: (i) developing a predictive model based on existing but disparate data sets, (ii) building an experimental design focused on the iso-hurdles using the model output, and (iii) validating the model and the iso-hurdle rules with new data. The methodology is illustrated with Listeria monocytogenes. Existing data from industry, a public database, and the literature were collected and analyzed, after which a total of 650 growth rates were retained. A gamma-type model was developed for the factors temperature, pH, a(w), and acetic, lactic, and sorbic acids. Three iso-hurdle rules were assessed (40 logcount curves generated): salt replacement by addition of organic acids, sorbic acid replacement by addition of acetic and lactic acid, and sorbic acid replacement by addition of lactic/acetic acid and salt. For the three rules, the growth rates were equivalent in the whole experimental domain (γ from 0.1 to 0.5). The lag times were also equivalent in the case of mild inhibitory conditions (γ ≥ 0.2), while they were longer in the presence of salt than acids under stress conditions (γ < 0.2). This methodology allows an assessment of the equivalence of inhibitory effects without intensive data generation; it could be applied to develop milder formulations which guarantee microbial safety and stability.
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Affiliation(s)
- Laure Pujol
- INRA, UMR1014 Secalim, Nantes, Francea; LUNAM Université, Oniris, Nantes, France.
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Finazzi G, Daminelli P, Serraino A, Pizzamiglio V, Riu R, Giacometti F, Bertasi B, Losio M, Boni P. Behaviour of Listeria monocytogenes in packaged water buffalo mozzarella cheese. Lett Appl Microbiol 2011; 53:364-70. [DOI: 10.1111/j.1472-765x.2011.03118.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Velugoti PR, Bohra LK, Juneja VK, Huang L, Wesseling AL, Subbiah J, Thippareddi H. Dynamic model for predicting growth of Salmonella spp. in ground sterile pork. Food Microbiol 2011; 28:796-803. [DOI: 10.1016/j.fm.2010.05.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Revised: 05/07/2010] [Accepted: 05/08/2010] [Indexed: 11/30/2022]
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Santiago L, Alves F, Pinheiro R, Santos VD, Rodrigues A, Chapaval L, Brito ID, Sousa FD. Avaliação in vitro da sensibilidade da Corynebacterium pseudotuberculosis frente a diferentes tipos de antissépticos e desinfetantes e determinação de sua curva de crescimento. ARQUIVOS DO INSTITUTO BIOLÓGICO 2010. [DOI: 10.1590/1808-1657v77p5932010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RESUMO O objetivo deste estudo foi avaliar o efeito in vitro de antissépticos e desinfetantes contra a Corynebacterium pseudotuberculosis e descrever a curva de crescimento deste micro-organismo em caldo de infusão de cérebro e coração adicionado de 0,1% de Tween 80 (BHI + T), ao longo de 48 horas. Foram avaliados tintura de iodo a 10%, hipoclorito de sódio a 2,5%, permanganato de potássio a 5%, sabonete líquido antisséptico Aseptol® e álcool etílico absoluto (99,8%), por meio da metodologia da disco-difusão. Um swab estéril foi imerso na suspensão bacteriana produzida e semeado em placa de ágar Mueller-Hinton. Discos estéreis foram embebidos em cada solução a ser testada e distribuídos na superfície do ágar. Os resultados foram obtidos de acordo com o diâmetro do halo produzido ao redor dos discos. Para obtenção da curva de crescimento, colônias isoladas do micro-organismo foram inoculadas em frasco contendo BHI + T. A cada quatro horas, 2 mL eram retirados para medição da massa celular em espectrofotômetro e 1 mL para realização das diluições seriadas, plaqueamento em ágar sangue e contagem de células viáveis. Observou-se que, para a obtenção de uma concentração máxima de C. pseudotuberculosis, próxima a 1.200 x 105 células viáveis/mL, deve-se manter o inóculo sob incubação adequada por um período de 28 a 40 horas. Quanto à prova de sensibilidade, verificou-se que a tintura de iodo a 10%, seguida pelo hipoclorito de sódio a 2,5% e permanganato de potássio a 5%, foram os antissépticos e desinfetantes com maior poder bactericida in vitro contra a C. pseudotuberculosis.
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Giuffrida A, Valenti D, Ziino G, Panebianco A. Study on the application of an interspecific competition model for the prediction of microflora behaviour during the fermentation process of S. Angelo PGI salami. Vet Res Commun 2009; 33 Suppl 1:229-32. [DOI: 10.1007/s11259-009-9293-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Ben Yaghlene H, Leguerinel I, Hamdi M, Mafart P. A new predictive dynamic model describing the effect of the ambient temperature and the convective heat transfer coefficient on bacterial growth. Int J Food Microbiol 2009; 133:48-61. [DOI: 10.1016/j.ijfoodmicro.2009.04.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2008] [Revised: 04/10/2009] [Accepted: 04/18/2009] [Indexed: 11/16/2022]
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A stochastic interspecific competition model to predict the behaviour of Listeria monocytogenes in the fermentation process of a traditional Sicilian salami. Eur Food Res Technol 2008. [DOI: 10.1007/s00217-008-0988-6] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Panagou EZ, Nychas GJE. Dynamic modeling of Listeria monocytogenes growth in pasteurized vanilla cream after postprocessing contamination. J Food Prot 2008; 71:1828-34. [PMID: 18810866 DOI: 10.4315/0362-028x-71.9.1828] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A product-specific model was developed and validated under dynamic temperature conditions for predicting the growth of Listeria monocytogenes in pasteurized vanilla cream, a traditional milk-based product. Model performance was also compared with Growth Predictor and Sym'Previus predictive microbiology software packages. Commercially prepared vanilla cream samples were artificially inoculated with a five-strain cocktail of L. monocytogenes, with an initial concentration of 102 CFU g(-1), and stored at 3, 5, 10, and 15 degrees C for 36 days. The growth kinetic parameters at each temperature were determined by the primary model of Baranyi and Roberts. The maximum specific growth rate (mu(max)) was further modeled as a function of temperature by means of a square root-type model. The performance of the model in predicting the growth of the pathogen under dynamic temperature conditions was based on two different temperature scenarios with periodic changes from 4 to 15 degrees C. Growth prediction for dynamic temperature profiles was based on the square root model and the differential equations of the Baranyi and Roberts model, which were numerically integrated with respect to time. Model performance was based on the bias factor (B(f)), the accuracy factor (A(f)), the goodness-of-fit index (GoF), and the percent relative errors between observed and predicted growth. The product-specific model developed in the present study accurately predicted the growth of L. monocytogenes under dynamic temperature conditions. The average values for the performance indices were 1.038, 1.068, and 0.397 for B(f), A(f), and GoF, respectively for both temperature scenarios assayed. Predictions from Growth Predictor and Sym'Previus overestimated pathogen growth. The average values of B(f), A(f), and GoF were 1.173, 1.174, 1.162, and 0.956, 1.115, 0.713 for [corrected] Growth Predictor and Sym'Previus, respectively.
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Affiliation(s)
- Efstathios Z Panagou
- Laboratory of Microbiology and Biotechnology of Foods, Department of Food Science and Technology, Agricultural University of Athens, Iera Odos 75, Athens 118 55, Greece.
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40
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Park JP, Lee DS. Analysis of Temperature Effects on Microbial Growth Parameters and Estimation of Food Shelf Life with Confidence Band. Prev Nutr Food Sci 2008. [DOI: 10.3746/jfn.2008.13.2.104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Martino KG, Marks BP. Comparing uncertainty resulting from two-step and global regression procedures applied to microbial growth models. J Food Prot 2007; 70:2811-8. [PMID: 18095435 DOI: 10.4315/0362-028x-70.12.2811] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Two different microbial modeling procedures were compared and validated against independent data for Listeria monocytogenes growth. The most generally used method is two consecutive regressions: growth parameters are estimated from a primary regression of microbial counts, and a secondary regression relates the growth parameters to experimental conditions. A global regression is an alternative method in which the primary and secondary models are combined, giving a direct relationship between experimental factors and microbial counts. The Gompertz equation was the primary model, and a response surface model was the secondary model. Independent data from meat and poultry products were used to validate the modeling procedures. The global regression yielded the lower standard errors of calibration, 0.95 log CFU/ml for aerobic and 1.21 log CFU/ml for anaerobic conditions. The two-step procedure yielded errors of 1.35 log CFU/ml for aerobic and 1.62 log CFU/ ml for anaerobic conditions. For food products, the global regression was more robust than the two-step procedure for 65% of the cases studied. The robustness index for the global regression ranged from 0.27 (performed better than expected) to 2.60. For the two-step method, the robustness index ranged from 0.42 to 3.88. The predictions were overestimated (fail safe) in more than 50% of the cases using the global regression and in more than 70% of the cases using the two-step regression. Overall, the global regression performed better than the two-step procedure for this specific application.
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Affiliation(s)
- K G Martino
- Department of Biosystems and Agricultural Engineering, A. W. Farrall Hall, Michigan State University, East Lansing, Michigan 48824, USA
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42
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Lee DS, Hwang KJ, An DS, Park JP, Lee HJ. Model on the microbial quality change of seasoned soybean sprouts for on-line shelf life prediction. Int J Food Microbiol 2007; 118:285-93. [PMID: 17804105 DOI: 10.1016/j.ijfoodmicro.2007.07.052] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Accepted: 07/28/2007] [Indexed: 10/23/2022]
Abstract
The growth of aerobic bacteria on Korean seasoned soybean sprouts was modelled as a function of temperature to estimate microbial spoilage and shelf life on a real-time basis under dynamic storage conditions. Counts of aerobic bacteria on seasoned soybean sprouts stored at constant temperatures between 0 degrees C and 15 degrees C were recorded. The bootstrapping method was applied to generate many resampled data sets of mean microbial plate counts that were then used to estimate the parameters of the microbial growth model of Baranyi and Roberts. The distributions of the model parameters were quantified, and their temperature dependencies were expressed as mathematical functions. When the temperature functions of the parameters were incorporated into differential equations describing microbial growth, predictions of microbial growth under fluctuating temperature conditions were similar to observed microbial growth.
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Affiliation(s)
- Dong Sun Lee
- Department of Food Science and Biotechnology, Kyungnam University, 449 Wolyoung-dong, Masan, 631-701, South Korea.
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Fujikawa H, Yano K, Morozumi S. Model comparison for Escherichia coli growth in pouched food. Food Hygiene and Safety Science (Shokuhin Eiseigaku Zasshi) 2006; 47:115-8. [PMID: 16862989 DOI: 10.3358/shokueishi.47.115] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We recently studied the growth characteristics of Escherichia coli cells in pouched mashed potatoes (Fujikawa et al., J. Food Hyg. Soc. Japan, 47, 95-98 (2006)). Using those experimental data, in the present study, we compared a logistic model newly developed by us with the modified Gompertz and the Baranyi models, which are used as growth models worldwide. Bacterial growth curves at constant temperatures in the range of 12 to 34 degrees C were successfully described with the new logistic model, as well as with the other models. The Baranyi gave the least error in cell number and our model gave the least error in the rate constant and the lag period. For dynamic temperature, our model successfully predicted the bacterial growth, whereas the Baranyi model considerably overestimated it. Also, there was a discrepancy between the growth curves described with the differential equations of the Baranyi model and those obtained with DMfit, a software program for Baranyi model fitting. These results indicate that the new logistic model can be used to predict bacterial growth in pouched food.
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Affiliation(s)
- Hiroshi Fujikawa
- Department of Microbiology, Tokyo Metropolitan Institute of Public Health: 3-24-1, Hyakunin-cho, Shinjuku-ku, Tokyo 169-0073, Japan
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Xanthiakos K, Simos D, Angelidis AS, Nychas GJE, Koutsoumanis K. Dynamic modeling of Listeria monocytogenes growth in pasteurized milk. J Appl Microbiol 2006; 100:1289-98. [PMID: 16696676 DOI: 10.1111/j.1365-2672.2006.02854.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS The development and validation of a dynamic model for predicting Listeria monocytogenes growth in pasteurized milk stored at both static and dynamic temperature conditions. METHODS AND RESULTS Growth of inoculated L. monocytogenes in a commercial pasteurized whole milk product was monitored at various isothermal conditions from 1.5 to 16 degrees C. The kinetic parameters of the pathogen were modelled as a function of temperature using a square root type model, which was further validated using data from 92 published growth curves from eight different milk products. Compared to four published models for L. monocytogenes growth, the model developed in this study performed better, with a per cent discrepancy and bias of 49.1 and -1.01%, respectively. The performance of the model in predicting growth at dynamic temperature conditions was evaluated at four different fluctuating temperature scenarios with periodic temperature changes from -2 to 16 degrees C. The prediction of growth at dynamic storage temperature was based on the square root model in conjunction with the differential equations of the Baranyi and Roberts model, which were numerically integrated with respect to time. The per cent relative errors between the observed and the predicted growth of L. monocytogenes were less than 10% for all temperature scenarios tested. CONCLUSIONS Available models from experiments conducted in laboratory media may result in significant overestimation of L. monocytogenes growth in pasteurized milk because they do not take into account factors such as milk composition (e.g. natural antimicrobial compounds present in milk) and the interactions of the pathogen with the natural microflora. The product-targeted model developed in the present study showed a high performance in predicting growth of L. monocytogenes in pasteurized milk under both static and dynamic temperature conditions. SIGNIFICANCE AND IMPACT OF THE STUDY Temperature fluctuations often occur during the transportation and storage of pasteurized milk. A high performance, dynamic model for the growth of L. monocytogenes can be a useful tool for effective management and optimization of product safety and can lead to more realistic estimations of pasteurized-milk related safety risks.
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Affiliation(s)
- K Xanthiakos
- Department of Food Science and Technology, Faculty of Agriculture, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Francois K, Valero A, Geeraerd AH, Van Impe JF, Debevere J, García-Gimeno RM, Zurera G, Devlieghere F. Effect of preincubation temperature and pH on the individual cell lag phase of Listeria monocytogenes, cultured at refrigeration temperatures. Food Microbiol 2006; 24:32-43. [PMID: 16943092 DOI: 10.1016/j.fm.2006.03.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2005] [Revised: 03/24/2006] [Accepted: 03/24/2006] [Indexed: 11/19/2022]
Abstract
The impact of precultural temperature and pH on the distribution of the lag phase of individual Listeria monocytogenes cells was assessed during preincubation at 7 degrees C, using a dilution protocol to obtain single cells, and optical density measurements to estimate the individual lag phase. Firstly, the pure temperature effect (37, 15, 10, 7, 4 and 2 degrees C) was investigated on a subsequent growth at 7 degrees C and pH 7.4. Secondly, low precultural temperatures (10, 7 and 4 degrees C) were combined with a controlled pH at 7.4 and 5.7 with a subsequent growth at 7 degrees C and at different pH values (7.4, 6.0 and 5.5). For all temperature-pH combinations, the individual cell lag phase was determined using a three-phase linear growth model. It was observed that at low precultural temperatures (2, 4 and 7 degrees C), a high proportion of L. monocytogenes cells were able to grow at 7 degrees C with almost no lag phase, consequently, the resulting distributions were positively skewed. Beside this, the variability observed was lower than at higher precultural temperatures. Regarding the precultural pH effect, at pH 7.4 the mean values of the lag phases were shorter at lower preincubation temperatures; while at pH 5.7 small pH transitions produced shorter individual lag phases at all precultural temperatures. The quantification of the effect of precultural conditions on the individual cell lag phase duration would improve the accuracy of the existing growth models, especially when a series of processing and storage steps are linked together in a process model or exposure assessment. Distributions will be fitted to the data for every set of conditions, generating useful tools for further risk assessment purposes.
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Affiliation(s)
- K Francois
- Laboratory of Food Microbiology and Food Preservation, Department of Food Safety and Food Quality, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
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46
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Abstract
Surface growth of Escherichia coli cells on a membrane filter placed on a nutrient agar plate under various conditions was studied with a mathematical model. The surface growth of bacterial cells showed a sigmoidal curve with time on a semilogarithmic plot. To describe it, a new logistic model that we presented earlier (H. Fujikawa et al., Food Microbiol. 21:501-509, 2004) was modified. Growth curves at various constant temperatures (10 to 34 degrees C) were successfully described with the modified model (model III). Model III gave better predictions of the rate constant of growth and the lag period than a modified Gompertz model and the Baranyi model. Using the parameter values of model III at the constant temperatures, surface growth at various temperatures was successfully predicted. Surface growth curves at various initial cell numbers were also sigmoidal and converged to the same maximum cell numbers at the stationary phase. Surface growth curves at various nutrient levels were also sigmoidal. The maximum cell number and the rate of growth were lower as the nutrient level decreased. The surface growth curve was the same as that in a liquid, except for the large curvature at the deceleration period. These curves were also well described with model III. The pattern of increase in the ATP content of cells grown on a surface was sigmoidal, similar to that for cell growth. We discovered several characteristics of the surface growth of bacterial cells under various growth conditions and examined the applicability of our model to describe these growth curves.
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Affiliation(s)
- Hiroshi Fujikawa
- Tokyo Metropolitan Institute of Public Health Department of Microbiology, Shinjuku, Tokyo 169-0073, Japan.
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Martino KG, Marks BP, Campos DT, Tamplin ML. Quantifying the robustness of a broth-based model for predicting Listeria monocytogenes growth in meat and poultry products. J Food Prot 2005; 68:2310-6. [PMID: 16300067 DOI: 10.4315/0362-028x-68.11.2310] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Given the importance of Listeria monocytogenes as a risk factor in meat and poultry products, there is a need to evaluate the relative robustness of predictive growth models applied to meat products. The U.S. Department of Agriculture-Agricultural Research Service Pathogen Modeling Program is a tool widely used by the food industry to estimate pathogen growth, survival, and inactivation in food. However, the robustness of the Pathogen Modeling Program broth-based L. monocytogenes growth model in meat and poultry application has not, to our knowledge, been specifically evaluated. In the present study, this model was evaluated against independent data in terms of predicted microbial counts and covered a range of conditions inside and outside the original model domain. The robustness index was calculated as the ratio of the standard error of prediction (root mean square error of the model against an independent data set not used to create the model) to the standard error of calibration (root mean square error of the model against the data set used to create the model). Inside the calibration domain of the Pathogen Modeling Program, the best robustness index for application to meat products was 0.37; the worst was 3.96. Outside the domain, the best robustness index was 0.40, and the worst was 1.22. Product type influenced the robustness index values (P < 0.01). In general, the results indicated that broth-based predictive models should be validated against independent data in the domain of interest; otherwise, significant predictive errors can occur.
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Affiliation(s)
- K G Martino
- Department of Biosystems and Agricultural Engineering, Michigan State University, A. W. Farrall Hall, East Lansing, Michigan 48824, USA
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48
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Koseki S, Isobe S. Prediction of pathogen growth on iceberg lettuce under real temperature history during distribution from farm to table. Int J Food Microbiol 2005; 104:239-48. [PMID: 15979180 DOI: 10.1016/j.ijfoodmicro.2005.02.012] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2004] [Revised: 02/01/2005] [Accepted: 02/19/2005] [Indexed: 10/25/2022]
Abstract
The growth of pathogenic bacteria Escherichia coli O157:H7, Salmonella spp., and Listeria monocytogenes on iceberg lettuce under constant and fluctuating temperatures was modelled in order to estimate the microbial safety of this vegetable during distribution from the farm to the table. Firstly, we examined pathogen growth on lettuce at constant temperatures, ranging from 5 to 25 degrees C, and then we obtained the growth kinetic parameters (lag time, maximum growth rate (micro(max)), and maximum population density (MPD)) using the Baranyi primary growth model. The parameters were similar to those predicted by the pathogen modelling program (PMP), with the exception of MPD. The MPD of each pathogen on lettuce was 2-4 log(10) CFU/g lower than that predicted by PMP. Furthermore, the MPD of pathogens decreased with decreasing temperature. The relationship between mu(max) and temperature was linear in accordance with Ratkowsky secondary model as was the relationship between the MPD and temperature. Predictions of pathogen growth under fluctuating temperature used the Baranyi primary microbial growth model along with the Ratkowsky secondary model and MPD equation. The fluctuating temperature profile used in this study was the real temperature history measured during distribution from the field at harvesting to the retail store. Overall predictions for each pathogen agreed well with observed viable counts in most cases. The bias and root mean square error (RMSE) of the prediction were small. The prediction in which mu(max) was based on PMP showed a trend of overestimation relative to prediction based on lettuce. However, the prediction concerning E. coli O157:H7 and Salmonella spp. on lettuce greatly overestimated growth in the case of a temperature history starting relatively high, such as 25 degrees C for 5 h. In contrast, the overall prediction of L. monocytogenes under the same circumstances agreed with the observed data.
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Affiliation(s)
- Shigenobu Koseki
- Food Processing Laboratory, National Food Research Institute, 2-1-12, Kannondai, Tsukuba, Ibaraki 305-8642, Japan.
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Narang N, Tamplin ML, Cray WC. Effect of refrigerating delayed shipments of raw ground beef on the detection of Salmonella Typhimurium. J Food Prot 2005; 68:1581-6. [PMID: 21132963 DOI: 10.4315/0362-028x-68.8.1581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In eight separate trials, four groups of raw ground beef samples were inoculated with 0.04 to 0.3 CFU/g of Salmonella Typhimurium (DT 104). Each group consisted of four 25-g samples (three inoculated and one uninoculated). After inoculation, these samples were shipped by overnight courier in Shipping containers with ice packs from the U.S. Department of Agriculture (USDA), Eastern Regional Research Center, in Wyndmoor, Pa., to the U.S. Food Safety and Inspection Service (FSIS), Eastern Laboratory, in Athens, Ga. A total of 128 samples (32 in each of four groups) were shipped. A temperature data logger was placed inside each shipping container to record the temperature during shipping and storage. The first group of ground beef samples was analyzed within approximately 1 h of arrival. The second group of samples was left in the original containers, with a gel ice pack, for 24 h before processing. The third and fourth groups of samples were removed from the original shipping containers and stored at room temperature (21 +/- 2 degrees C) for 6 h and then in a refrigerator at 4 +/- 2 degrees C for 24 and 48 h, respectively, before analysis. The samples were analyzed for the presence of Salmonella according to the USDA/FSIS Microbiological Laboratory Guidebook, chapter 4.02. There was no significant difference in the presence and levels of Salmonella in ground beef among the four test groups. These data show that it is acceptable to process the late-arriving ground beef samples for the detection of Salmonella if they are kept in a refrigerator (4 +/- 2 degrees C) for 24 to 48 h or when the shipments arrive late (24 h in the container with ice pack).
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Affiliation(s)
- Neelam Narang
- Eastern Regional Research Center, Microbial Food Safety Research Unit, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA.
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Fujikawa H, Morozumi S. Modeling Staphylococcus aureus growth and enterotoxin production in milk. Food Microbiol 2005; 23:260-7. [PMID: 16943012 DOI: 10.1016/j.fm.2005.04.005] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2005] [Revised: 04/05/2005] [Accepted: 04/05/2005] [Indexed: 11/21/2022]
Abstract
Staphylococcus aureus growth and its enterotoxin production in sterilized milk were modeled with a modification of a new logistic model recently developed by us. The modified model and the Baranyi model described the early exponential phase of a growth curve more accurately than the previous model, at constant temperatures from 14 to 36.5 degrees C. The amount of toxin in milk increased linearly with time from the time the cell population reached about 10(6.5) cfu/ml. The rate of toxin production linearly increased at temperatures between 14 and 32 degrees C. From parameter values obtained at the constant temperatures, the model successfully predicted bacterial growth in the milk at a varying temperature. For toxin level estimation, we postulated that the rate of toxin production might be regulated with the temperature after the cell concentration reached 10(6.5) cfu/ml; the time point when the cell concentration reached that value was predicted with the modified growth model. Introduction of a correction factor in the toxin estimation successfully predicted the toxin level in milk at a varying temperature. These results showed that this prediction system consisting of the modified model and the toxin production algorithm might be a useful tool for modeling bacterial growth and its metabolite production in liquid foods.
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Affiliation(s)
- Hiroshi Fujikawa
- Department of Microbiology, Tokyo Metropolitan Institute of Public Health, 3-24-1, Hyakunin-cho, Shinjuku, Tokyo 169-0073, Japan.
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