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Bansal V, Veena N. Understanding the role of pH in cheese manufacturing: general aspects of cheese quality and safety. JOURNAL OF FOOD SCIENCE AND TECHNOLOGY 2024; 61:16-26. [PMID: 38192705 PMCID: PMC10771476 DOI: 10.1007/s13197-022-05631-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 08/10/2022] [Accepted: 10/07/2022] [Indexed: 11/30/2022]
Abstract
Cheese production has emerged as science and technology in the past few years, which was considered an artisan craft in the earlier period. However, despite intensive research work from many decades, the complex changes that occur during preparation and ripening of cheese are not apparent, affecting the quality and safety of cheese. Over time, several factors are studied and reviewed that affect cheese quality. The pH of the cheese curd matrix from manufacturing till ripening is one of the most crucial parameters that governs several aspects of cheese quality. Therefore, this paper aims to highlight the effect of pH on various processes (such as rennet coagulation, whey syneresis, salt absorption and ripening), microstructure and dynamic rheology, and microbiological changes that regulate the overall quality and safety aspects of cheeses. Understanding the role of pH on cheese quality parameters will aid to make better and more consistent cheeses that will satisfy both the consumers and cheese-makers.
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Affiliation(s)
- Venus Bansal
- Department of Dairy Technology, College of Dairy Science and Technology, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab 141004 India
| | - N. Veena
- Department of Dairy Chemistry, College of Dairy Science and Technology, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab 141004 India
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2
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Microbiological Testing by Industry of Ready-to-Eat Foods under FDA's Jurisdiction for Pathogens (or Appropriate Indicator Organisms): Verification of Preventive Controls. J Food Prot 2022; 85:1646-1666. [PMID: 36099067 DOI: 10.4315/jfp-22-143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/17/2022] [Indexed: 11/11/2022]
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3
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Flynn BT, Kozak SM, Lawton MR, Alcaine SD. Lactose oxidase: An enzymatic approach to inhibit Listeria monocytogenes in milk. J Dairy Sci 2021; 104:10594-10608. [PMID: 34334205 DOI: 10.3168/jds.2021-20450] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 06/16/2021] [Indexed: 12/18/2022]
Abstract
Listeria monocytogenes is a ubiquitous pathogen that can cause morbidity and mortality in immunocompromised individuals. Growth of L. monocytogenes is possible at refrigeration temperatures due to its psychrotrophic nature. The use of antimicrobials in dairy products is a potential way to control L. monocytogenes growth in processes with no thermal kill step, thereby enhancing the safety of such products. Microbial-based enzymes offer a clean-label approach for control of L. monocytogenes outgrowth. Lactose oxidase (LO) is a microbial-derived enzyme with antimicrobial properties. It oxidizes lactose into lactobionic acid and reduces oxygen, generating H2O2. This study investigated the effects of LO in UHT skim milk using different L. monocytogenes contamination scenarios. These LO treatments were then applied to raw milk with various modifications; higher levels of LO as well as supplementation with thiocyanate were added to activate the lactoperoxidase system, a natural antimicrobial system present in milk. In UHT skim milk, concentrations of 0.0060, 0.012, and 0.12 g/L LO each reduced L. monocytogenes counts to below the limit of detection between 14 and 21 d of refrigerated storage, dependent on the concentration of LO. In the 48-h trials in UHT skim milk, LO treatments were effective in a concentration-dependent fashion. The highest concentration of LO in the 21-d trials, 0.12 g/L, did not show great inhibition over 48 h, so concentrations were increased for these experiments. In the lower inoculum, after 48 h, a 12 g/L LO treatment reached levels of 1.7 log cfu/mL, a reduction of 1.3 log cfu/mL from the initial inoculum, whereas the control grew out to approximately 4 log cfu/mL, an increase of 1 log cfu/mL from the inoculum on d 0. When a higher challenge inoculum of 5 log cfu/mL was used, the 0.12 g/L and 1.2 g/L treatments reduced the levels by 0.2 to 0.3 log cfu/mL below the initial inoculum and the 12 g/L treatment by >1 log cfu/mL below the initial inoculum by hour 48 of storage at refrigeration temperatures. After the efficacy of LO was determined in UHT skim milk, LO treatments were applied to raw milk. Concentrations of LO were increased, and the addition of thiocyanate was investigated to supplement the effect of the lactoperoxidase system against L. monocytogenes. When raw milk was inoculated with 2 log cfu/mL, 1.2 g/L LO alone and combined with sodium thiocyanate reduced ~0.8 log cfu/mL from the initial inoculum on d 7 of storage, whereas the control grew out to >1 log cfu/mL from the initial inoculum. Furthermore, in the higher inoculum, 1.2 g/L LO combined with sodium thiocyanate reduced L. monocytogenes counts from the initial inoculum by >1 log cfu/mL, whereas the control grew out 2 log cfu/mL from the initial inoculum. Results from this study suggest that LO is inhibitory against L. monocytogenes in UHT skim milk and in raw milk. Therefore, LO may be an effective treatment to prevent L. monocytogenes outgrowth, increase the safety of raw milk, and be used as an effective agent to prevent L. monocytogenes proliferation in fresh cheese and other dairy products. This enzymatic approach is a novel application to control the foodborne pathogen L. monocytogenes in dairy products.
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Affiliation(s)
- Brenna T Flynn
- Department of Food Science, Cornell University, Ithaca, NY 14853
| | - Sarah M Kozak
- Department of Food Science, Cornell University, Ithaca, NY 14853
| | - Marie R Lawton
- Department of Food Science, Cornell University, Ithaca, NY 14853
| | - Samuel D Alcaine
- Department of Food Science, Cornell University, Ithaca, NY 14853.
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Falardeau J, Trmčić A, Wang S. The occurrence, growth, and biocontrol of Listeria monocytogenes in fresh and surface-ripened soft and semisoft cheeses. Compr Rev Food Sci Food Saf 2021; 20:4019-4048. [PMID: 34057273 DOI: 10.1111/1541-4337.12768] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/16/2021] [Accepted: 04/17/2021] [Indexed: 01/05/2023]
Abstract
Listeria monocytogenes continues to pose a food safety risk in ready-to-eat foods, including fresh and soft/semisoft cheeses. Despite L. monocytogenes being detected regularly along the cheese production continuum, variations in cheese style and intrinsic/extrinsic factors throughout the production process (e.g., pH, water activity, and temperature) affect the potential for L. monocytogenes survival and growth. As novel preservation strategies against the growth of L. monocytogenes in susceptible cheeses, researchers have investigated the use of various biocontrol strategies, including bacteriocins and bacteriocin-producing cultures, bacteriophages, and competition with native microbiota. Bacteriocins produced by lactic acid bacteria (LAB) are of particular interest to the dairy industry since they are often effective against Gram-positive organisms such as L. monocytogenes, and because many LAB are granted Generally Regarded as Safe (GRAS) status by global food safety authorities. Similarly, bacteriophages are also considered a safe form of biocontrol since they have high specificity for their target bacterium. Both bacteriocins and bacteriophages have shown success in reducing L. monocytogenes populations in cheeses in the short term, but regrowth of surviving cells can commonly occur in the finished cheeses. Competition with native microbiota, not mediated by bacteriocin production, has also shown potential to inhibit the growth of L. monocytogenes in cheeses, but the mechanisms are still unclear. Here, we have reviewed the current knowledge on the growth of L. monocytogenes in fresh and surface-ripened soft and semisoft cheeses, as well as the various methods used for biocontrol of this common foodborne pathogen.
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Affiliation(s)
- Justin Falardeau
- Department of Food, Nutrition, and Health, University of British Columbia, British Columbia, Vancouver, Canada
| | - Aljoša Trmčić
- Milk Quality Improvement Program, Department of Food Science, Cornell University, Ithaca, New York, USA
| | - Siyun Wang
- Department of Food, Nutrition, and Health, University of British Columbia, British Columbia, Vancouver, Canada
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5
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Martinez-Rios V, Gkogka E, Dalgaard P. Predicting growth of Listeria monocytogenes at dynamic conditions during manufacturing, ripening and storage of cheeses - Evaluation and application of models. Food Microbiol 2020; 92:103578. [PMID: 32950162 DOI: 10.1016/j.fm.2020.103578] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 05/19/2020] [Accepted: 06/20/2020] [Indexed: 12/14/2022]
Abstract
Mathematical models were evaluated to predict growth of L. monocytogenes in mould/smear-ripened cheeses with measured dynamic changes in product characteristics and storage conditions. To generate data for model evaluation three challenge tests were performed with mould-ripened cheeses produced by using milk inoculated with L. monocytogenes. Growth of L. monocytogenes and lactic acid bacteria (LAB) in the rind and in the core of cheeses were quantified together with changes in product characteristics over time (temperature, pH, NaCl/aw, lactic- and acetic acid concentrations). The performance of nine available L. monocytogenes growth models was evaluated using growth responses from the present study and from literature together with the determined or reported dynamic product characteristics and storage conditions (46 kinetics). The acceptable simulation zone (ASZ) method was used to assess model performance. A reduced version of the Martinez-Rios et al. (2019) model (https://doi.org/10.3389/fmicb.2019.01510) and the model of Østergaard et al. (2014) (https://doi.org/10.1016/j.ijfoodmicro.2014.07.012) had acceptable performance with a ASZ-score of 71-70% for L. monocytogenes growth in mould/smear-ripened cheeses. Models from Coroller et al. (2012) (https://doi.org/10.1016/j.ijfoodmicro.2011.09.023) had close to acceptable performance with ASZ-scores of 67-69%. The validated models (Martinez-Rios et al., 2019; Østergaard et al., 2014) can be used to facilitate the evaluation of time to critical L. monocytogenes growth for mould/smear-ripened cheeses including modification of recipes with for example reduced salt/sodium or to support exposure assessment studies for these cheeses.
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Affiliation(s)
- Veronica Martinez-Rios
- National Food Institute (DTU Food), Technical University of Denmark, Kgs. Lyngby, Denmark.
| | | | - Paw Dalgaard
- National Food Institute (DTU Food), Technical University of Denmark, Kgs. Lyngby, Denmark
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Aljasir SF, D'Amico DJ. The effect of protective cultures on Staphylococcus aureus growth and enterotoxin production. Food Microbiol 2020; 91:103541. [PMID: 32539968 DOI: 10.1016/j.fm.2020.103541] [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: 02/21/2020] [Revised: 04/01/2020] [Accepted: 04/30/2020] [Indexed: 10/24/2022]
Abstract
Staphylococcus aureus is the causative agent of staphylococcal food poisoning and is a common contaminant in milk. Despite efforts to control S. aureus, recalls and outbreaks continue to occur, highlighting the need for additional interventions. This study determined the potential for protective cultures (PC) that are commercially available to producers to control S. aureus growth in raw milk and attenuate virulence by impeding staphylococcal enterotoxin (SE) production in raw milk and laboratory medium. Cultures of Hafnia alvei and Lactococcus lactis effectively inhibited S. aureus growth in raw milk to counts ~5 log CFU/mL lower than control when cocultured following a cheesemaking time and temperature profile; two cultures of Lactobacillus plantarum inhibited growth to ~1.5 log CFU/mL less than control. Cocultures of S. aureus with Lc. lactis, H. alvei and Lb. plantarum in raw milk reduced SE levels by 24.9%, 62.4%, and 76%, respectively. Lc. lactis also decreased SE production in raw milk in the absence of PC-mediated growth inhibition. Significant reductions in SE production in the absence of pathogen growth inhibition were also achieved in laboratory medium. Together, these results demonstrate the potential for PCs to inhibit S. aureus growth and impede SE production in the absence of growth inhibition.
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Affiliation(s)
- Sulaiman F Aljasir
- Department of Animal Science, University of Connecticut, U-4163, Agricultural Biotechnology Laboratory, 1390 Storrs Road, Storrs, Connecticut 06269, USA.
| | - Dennis J D'Amico
- Department of Animal Science, University of Connecticut, U-4163, Agricultural Biotechnology Laboratory, 1390 Storrs Road, Storrs, Connecticut 06269, USA.
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7
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The efficacy of individual and combined commercial protective cultures against Listeria monocytogenes, Salmonella, O157 and non-O157 shiga toxin-producing Escherichia coli in growth medium and raw milk. Food Control 2020. [DOI: 10.1016/j.foodcont.2019.106924] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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8
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Salazar JK, Gonsalves LJ, Natarajan V, Shazer A, Reineke K, Mhetras T, Sule C, Carstens CK, Schill KM, Tortorello ML. Population Dynamics of Listeria monocytogenes, Escherichia coli O157:H7, and Native Microflora During Manufacture and Aging of Gouda Cheese Made with Unpasteurized Milk. J Food Prot 2020; 83:266-276. [PMID: 31961226 DOI: 10.4315/0362-028x.jfp-18-480] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 10/17/2019] [Indexed: 11/11/2022]
Abstract
ABSTRACT Cheeses made with unpasteurized milk are a safety concern due to possible contamination with foodborne pathogens. Listeria monocytogenes and Escherichia coli O157:H7 have been implicated in several outbreaks and recalls linked to Gouda cheese made with unpasteurized milk. The U.S. Food and Drug Administration Code of Federal Regulations requires cheeses made with unpasteurized milk to be aged at a minimum of 1.7°C for at least 60 days before entering interstate commerce. The goal of this study was (i) to assess the population dynamics of L. monocytogenes and E. coli O157:H7 during aging of Gouda cheese when the pathogens were inoculated into the unpasteurized milk used for manufacture and (ii) to compare the native microbial populations throughout manufacture and aging. Unpasteurized milk was inoculated with L. monocytogenes at 1 or 3 log CFU/mL or with E. coli O157:H7 at 1 log CFU/mL, and Gouda cheese was manufactured in laboratory-scale or pilot plant-scale settings. Cheeses were stored at 10°C for at least 90 days, and some cheeses were stored up to 163 days. Initial native microflora populations in unpasteurized milk did not differ significantly for laboratory-scale or pilot plant-scale trials, and population dynamics trended similarly throughout cheese manufacture and aging. During manufacture, approximately 81% of the total L. monocytogenes and E. coli O157:H7 populations was found in the curd samples. At an inoculation level of 1 log CFU/mL, L. monocytogenes survived in the cheese beyond 60 days in four of five trials. In contrast, E. coli O157:H7 was detected beyond 60 days in only one trial. At the higher 3-log inoculation level, the population of L. monocytogenes increased significantly from 3.96 ± 0.07 log CFU/g at the beginning of aging to 6.00 ± 0.73 log CFU/g after 150 days, corresponding to a growth rate of 0.04 ± 0.02 log CFU/g/day. The types of native microflora assessed included Enterobacteriaceae, lactic acid bacteria, mesophilic bacteria, and yeasts and molds. Generally, lactic acid and mesophilic bacterial populations remained consistent at approximately 8 to 9 log CFU/g during aging, whereas yeast and mold populations steadily increased. The data from this study will contribute to knowledge about survival of these pathogens during Gouda cheese production and will help researchers assess the risks of illness from consumption of Gouda cheese made with unpasteurized milk. HIGHLIGHTS
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Affiliation(s)
- Joelle K Salazar
- U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Lauren J Gonsalves
- U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Vidya Natarajan
- Institute for Food Safety and Health, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Arlette Shazer
- U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Karl Reineke
- U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Tanvi Mhetras
- Institute for Food Safety and Health, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Chinmyee Sule
- Institute for Food Safety and Health, Illinois Institute of Technology, 6502 South Archer Road, Bedford Park, Illinois 60501, USA
| | - Christina K Carstens
- U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Kristin M Schill
- U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501
| | - Mary Lou Tortorello
- U.S. Food and Drug Administration, Division of Food Processing Science and Technology, 6502 South Archer Road, Bedford Park, Illinois 60501
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9
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Batty D, Meunier-Goddik L, Waite-Cusic JG. Camembert-type cheese quality and safety implications in relation to the timing of high-pressure processing during aging. J Dairy Sci 2019; 102:8721-8733. [DOI: 10.3168/jds.2018-16236] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 05/07/2019] [Indexed: 11/19/2022]
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10
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de Medeiros Carvalho M, de Fariña LO, Strongin D, Ferreira CLLF, Lindner JDD. Traditional Colonial-type cheese from the south of Brazil: A case to support the new Brazilian laws for artisanal cheese production from raw milk. J Dairy Sci 2019; 102:9711-9720. [PMID: 31447161 DOI: 10.3168/jds.2019-16373] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 06/10/2019] [Indexed: 11/19/2022]
Abstract
Artisanal Colonial-type cheese is made from raw milk and is the main cheese produced by rural families of the southern region of Brazil. The aim of this study was to investigate, identify problems, and propose solutions for the current situation of small family farms producing and informally selling artisanal Colonial-type cheese located in the western part of Santa Catarina State in Southern Brazil. A semistructured questionnaire was employed in 12 rural properties to analyze the mode of production. Physical-chemical and microbiological analyses of water, raw milk, and cheese were performed, and it was found that 92, 50, and 100% of the samples, respectively, were outside of the current Brazilian regulatory parameters. None of the cheesemakers involved in this study met the requirements, as established by law, for artisanal cheese production from raw milk. This study concluded that technical support and changes in public policy are needed to ensure the preservation of this artisanal cheese, considering the historical importance and cultural traditions of these local communities and the socioeconomic importance of cheesemaking to family farming. Furthermore, more research on the safety of the cheese produced from raw milk is needed as well as the development of specific microbiological standards for artisanal Brazilian cheeses. Public policies aimed at guaranteeing food safety that formalize the commercialization of these cheeses will increase food security in those communities that currently produce artisanal cheese informally.
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Affiliation(s)
- Michelle de Medeiros Carvalho
- Departamento de Ciência e Tecnologia de Alimentos, Universidade Federal de Santa Catarina, 88034-001, Florianópolis, SC, Brazil
| | - Luciana Oliveira de Fariña
- Departamento de Ciências Agrárias, Universidade Estadual do Oeste do Paraná, 85960-000, Marechal Candido Rondon, PR, Brazil
| | - Daniel Strongin
- IM Organização e Planejamento Ltda, 22281-080, Rio de Janeiro, RJ, Brazil
| | - Célia Lucia L F Ferreira
- Departamento de Ciência e Tecnologia de Alimentos, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil
| | - Juliano De Dea Lindner
- Departamento de Ciência e Tecnologia de Alimentos, Universidade Federal de Santa Catarina, 88034-001, Florianópolis, SC, Brazil.
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Protective effect of reuterin-producing Lactobacillus reuteri against Listeria monocytogenes and Escherichia coli O157:H7 in semi-hard cheese. Food Control 2018. [DOI: 10.1016/j.foodcont.2017.08.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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13
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Currie A, Galanis E, Chacon PA, Murray R, Wilcott L, Kirkby P, Honish L, Franklin K, Farber J, Parker R, Shyng S, Sharma D, Tschetter L, Hoang L, Chui L, Pacagnella A, Wong J, Pritchard J, Kerr A, Taylor M, Mah V, Flint J. Outbreak of Escherichia coli O157:H7 Infections Linked to Aged Raw Milk Gouda Cheese, Canada, 2013. J Food Prot 2018; 81:325-331. [PMID: 29369688 DOI: 10.4315/0362-028x.jfp-17-283] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Between 12 July and 29 September 2013, 29 individuals in five Canadian provinces became ill following infection with the same strain of Escherichia coli O157:H7 as defined by molecular typing results. Five case patients were hospitalized, and one died. Twenty-six case patients (90%) reported eating Gouda cheese originating from a dairy plant in British Columbia. All of the 22 case patients with sufficient product details available reported consuming Gouda cheese made with raw milk; this cheese had been produced between March and July 2013 and was aged for a minimum of 60 days. The outbreak strain was isolated from the implicated Gouda cheese, including one core sample obtained from an intact cheese wheel 83 days after production. The findings indicate that raw milk was the primary source of the E. coli O157:H7, which persisted through production and the minimum 60-day aging period. This outbreak is the third caused by E. coli O157:H7 traced to Gouda cheese made with raw milk in North America. These findings provide further evidence that a 60-day ripening period cannot ensure die-off of pathogens that might be present in raw milk Gouda cheese after production and have triggered an evaluation of processing conditions, physicochemical parameters, and options to mitigate the risk of E. coli O157:H7 infection associated with raw milk Gouda cheese produced in Canada.
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Affiliation(s)
- Andrea Currie
- 1 Centre for Foodborne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, Ontario, Canada N1H 8J1
| | - Eleni Galanis
- 2 Communicable Disease Prevention and Control Services
| | - Pedro A Chacon
- 3 Canadian Food Inspection Agency, Ottawa, Ontario, Canada K1A 0Y9
| | - Regan Murray
- 1 Centre for Foodborne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, Ontario, Canada N1H 8J1
| | | | - Paul Kirkby
- 3 Canadian Food Inspection Agency, Ottawa, Ontario, Canada K1A 0Y9
| | - Lance Honish
- 5 Alberta Health Services, Edmonton, Alberta, Canada T5J 2Y2
| | - Kristyn Franklin
- 1 Centre for Foodborne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, Ontario, Canada N1H 8J1
| | - Jeff Farber
- 6 Bureau of Microbial Hazards, Health Canada, Ottawa, Ontario, Canada K1A 0K9.,7 University of Guelph, Guelph, Ontario, Canada N1G 2W1
| | - Rob Parker
- 8 Interior Health Authority, Kelowna, British Columbia, Canada V1Y 0C5
| | | | - Davendra Sharma
- 3 Canadian Food Inspection Agency, Ottawa, Ontario, Canada K1A 0Y9
| | - Lorelee Tschetter
- 9 National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada R3E 3R2
| | - Linda Hoang
- 10 British Columbia Public Health Microbiology and Reference Laboratory, Centre for Disease Control, Vancouver, British Columbia, Canada V5Z 4R4
| | - Linda Chui
- 11 Provincial Laboratory for Public Health, Edmonton, Alberta, Canada T2N 4W4.,12 Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada T6G 2R7
| | - Ana Pacagnella
- 10 British Columbia Public Health Microbiology and Reference Laboratory, Centre for Disease Control, Vancouver, British Columbia, Canada V5Z 4R4
| | - Julie Wong
- 10 British Columbia Public Health Microbiology and Reference Laboratory, Centre for Disease Control, Vancouver, British Columbia, Canada V5Z 4R4
| | - Jane Pritchard
- 13 Ministry of Agriculture, Abbotsford, British Columbia, Canada V3G 2M3; and
| | - Ashley Kerr
- 1 Centre for Foodborne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, Ontario, Canada N1H 8J1
| | - Marsha Taylor
- 2 Communicable Disease Prevention and Control Services
| | - Victor Mah
- 14 Alberta Health, Edmonton, Alberta, Canada T5J 1S6
| | - James Flint
- 1 Centre for Foodborne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, Ontario, Canada N1H 8J1
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14
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Boor KJ, Wiedmann M, Murphy S, Alcaine S. A 100-Year Review: Microbiology and safety of milk handling. J Dairy Sci 2017; 100:9933-9951. [DOI: 10.3168/jds.2017-12969] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/16/2017] [Indexed: 01/30/2023]
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15
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Jayanth HS, Varadaraj MC. Survival of a native toxigenic isolate of Listeria monocytogenes CFR 1302 during storage of milk-based foods can be a potential cause of health risk. FOOD SCI TECHNOL INT 2017; 23:426-436. [PMID: 28675967 DOI: 10.1177/1082013217698329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The ability of a native toxigenic culture of Listeria monocytogenes CFR 1302 to survive and elaborate associated toxigenic trait in ice cream and mango pulp-based lactic fermented milk was studied. The culture of L. monocytogenes inoculated at two initial levels of 4.6 and 5.6 log10 CFU/ml almost remained unaltered during storage of the food products. However, in both the milk-based products, a marginal increase in viable population was observed during 2-4 d of storage as against the initial inoculum levels. The toxigenic trait, listeriolysin "O" was detected by PCR based on species-specific hlyA primers in the two products without any step of enrichment. The positive amplification in PCR was evidenced with initial population levels of 6.3, 7.3, and 8.3 log10 CFU/ml of the respective products. In culture broth, PCR detection was positive with the lowest level of 2.3 log10 CFU/ml. The established pathogenic strain of L. monocytogenes Scott A used as a reference culture revealed almost the same behavior to that of native culture in the food products. The findings of present study bring into focus that, irrespective of low storage temperatures, there exists the potential health hazard associated with foods initially contaminated with risk population levels of L. monocytogenes.
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Affiliation(s)
- Hampapura S Jayanth
- 1 Department of Microbiology and Fermentation Technology, CSIR-Central Food Technological Research Institute, Mysore, India.,2 Department of Microbiology, Yuvaraja's College, University of Mysore, Mysore, India
| | - Mandyam C Varadaraj
- 1 Department of Microbiology and Fermentation Technology, CSIR-Central Food Technological Research Institute, Mysore, India
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16
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Verraes C, Vlaemynck G, Van Weyenberg S, De Zutter L, Daube G, Sindic M, Uyttendaele M, Herman L. A review of the microbiological hazards of dairy products made from raw milk. Int Dairy J 2015. [DOI: 10.1016/j.idairyj.2015.05.011] [Citation(s) in RCA: 98] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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17
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Abstract
The history of cheese manufacture is a "natural history" in which animals, microorganisms, and the environment interact to yield human food. Part of the fascination with cheese, both scientifically and culturally, stems from its ability to assume amazingly diverse flavors as a result of seemingly small details in preparation. In this review, we trace the roots of cheesemaking and its development by a variety of human cultures over centuries. Traditional cheesemakers observed empirically that certain environments and processes produced the best cheeses, unwittingly selecting for microorganisms with the best biochemical properties for developing desirable aromas and textures. The focus of this review is on the role of fungi in cheese ripening, with a particular emphasis on the yeast-like fungus Geotrichum candidum. Conditions that encourage the growth of problematic fungi such as Mucor and Scopulariopsis as well as Arachnida (cheese mites), and how such contaminants might be avoided, are discussed. Bethlehem cheese, a pressed, uncooked, semihard, Saint-Nectaire-type cheese manufactured in the United Sates without commercial strains of bacteria or fungi, was used as a model for the study of stable microbial succession during ripening in a natural environment. The appearance of fungi during a 60-day ripening period was documented using light and scanning electron microscopy, and it was shown to be remarkably reproducible and parallel to the course of ripening of authentic Saint-Nectaire cheese in the Auvergne region of France. Geotrichum candidum, Mucor, and Trichothecium roseum predominate the microbiotas of both cheese types. Geotrichum in particular was shown to have high diversity in different traditional cheese ripening environments, suggesting that traditional manufacturing techniques selected for particular fungi. This and other studies suggest that strain diversity arises in relation to the lore and history of the regions from which these types of cheeses arose.
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McIntyre L, Wilcott L, Naus M. Listeriosis outbreaks in British Columbia, Canada, caused by soft ripened cheese contaminated from environmental sources. BIOMED RESEARCH INTERNATIONAL 2015; 2015:131623. [PMID: 25918702 PMCID: PMC4396127 DOI: 10.1155/2015/131623] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 12/19/2014] [Accepted: 12/22/2014] [Indexed: 11/17/2022]
Abstract
Soft ripened cheese (SRC) caused over 130 foodborne illnesses in British Columbia (BC), Canada, during two separate listeriosis outbreaks. Multiple agencies investigated the events that lead to cheese contamination with Listeria monocytogenes (L.m.), an environmentally ubiquitous foodborne pathogen. In both outbreaks pasteurized milk and the pasteurization process were ruled out as sources of contamination. In outbreak A, environmental transmission of L.m. likely occurred from farm animals to personnel to culture solutions used during cheese production. In outbreak B, birds were identified as likely contaminating the dairy plant's water supply and cheese during the curd-washing step. Issues noted during outbreak A included the risks of operating a dairy plant in a farm environment, potential for transfer of L.m. from the farm environment to the plant via shared toilet facilities, failure to clean and sanitize culture spray bottles, and cross-contamination during cheese aging. L.m. contamination in outbreak B was traced to wild swallows defecating in the plant's open cistern water reservoir and a multibarrier failure in the water disinfection system. These outbreaks led to enhanced inspection and surveillance of cheese plants, test and release programs for all SRC manufactured in BC, improvements in plant design and prevention programs, and reduced listeriosis incidence.
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Affiliation(s)
- Lorraine McIntyre
- Environmental Health Services, BC Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, Canada V5Z 4R4
| | - Lynn Wilcott
- Environmental Health Services, BC Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, Canada V5Z 4R4
| | - Monika Naus
- Immunization Programs and Vaccine Preventable Diseases Services, BC Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, Canada V5Z 4R4
- School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada V6T 1Z9
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Fernández M, Hudson JA, Korpela R, de los Reyes-Gavilán CG. Impact on human health of microorganisms present in fermented dairy products: an overview. BIOMED RESEARCH INTERNATIONAL 2015; 2015:412714. [PMID: 25839033 PMCID: PMC4369881 DOI: 10.1155/2015/412714] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 09/04/2014] [Indexed: 02/07/2023]
Abstract
Fermented dairy products provide nutrients in our diet, some of which are produced by the action of microorganisms during fermentation. These products can be populated by a diverse microbiota that impacts the organoleptic and physicochemical characteristics foods as well as human health. Acidification is carried out by starter lactic acid bacteria (LAB) whereas other LAB, moulds, and yeasts become dominant during ripening and contribute to the development of aroma and texture in dairy products. Probiotics are generally part of the nonstarter microbiota, and their use has been extended in recent years. Fermented dairy products can contain beneficial compounds, which are produced by the metabolic activity of their microbiota (vitamins, conjugated linoleic acid, bioactive peptides, and gamma-aminobutyric acid, among others). Some microorganisms can also release toxic compounds, the most notorious being biogenic amines and aflatoxins. Though generally considered safe, fermented dairy products can be contaminated by pathogens. If proliferation occurs during manufacture or storage, they can cause sporadic cases or outbreaks of disease. This paper provides an overview on the current state of different aspects of the research on microorganisms present in dairy products in the light of their positive or negative impact on human health.
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Affiliation(s)
- María Fernández
- Instituto de Productos Lácteos de Asturias, Consejo Superior de Investigaciones Científicas (IPLA-CSIC), Paseo Río Linares s/n, Villaviciosa, 33300 Asturias, Spain
| | - John Andrew Hudson
- Food Safety Programme, ESR-Christchurch Science Centre, Christchurch 8540, New Zealand
- Food and Environment Safety Programme, The Food and Environment Research Agency, Sand Hutton, York YO41 1LZ, UK
| | - Riitta Korpela
- Medical Nutrition Physiology Group, Pharmacology, Institute of Biomedicine, University of Helsinki, 00014 Helsinki, Finland
| | - Clara G. de los Reyes-Gavilán
- Instituto de Productos Lácteos de Asturias, Consejo Superior de Investigaciones Científicas (IPLA-CSIC), Paseo Río Linares s/n, Villaviciosa, 33300 Asturias, Spain
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Melo J, Andrew P, Faleiro M. Listeria monocytogenes in cheese and the dairy environment remains a food safety challenge: The role of stress responses. Food Res Int 2015. [DOI: 10.1016/j.foodres.2014.10.031] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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21
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Gould LH, Mungai E, Behravesh CB. Outbreaks attributed to cheese: differences between outbreaks caused by unpasteurized and pasteurized dairy products, United States, 1998-2011. Foodborne Pathog Dis 2014; 11:545-51. [PMID: 24750119 PMCID: PMC4593610 DOI: 10.1089/fpd.2013.1650] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
INTRODUCTION The interstate commerce of unpasteurized fluid milk, also known as raw milk, is illegal in the United States, and intrastate sales are regulated independently by each state. However, U.S. Food and Drug Administration regulations allow the interstate sale of certain types of cheeses made from unpasteurized milk if specific aging requirements are met. We describe characteristics of these outbreaks, including differences between outbreaks linked to cheese made from pasteurized or unpasteurized milk. METHODS We reviewed reports of outbreaks submitted to the Foodborne Disease Outbreak Surveillance System during 1998-2011 in which cheese was implicated as the vehicle. We describe characteristics of these outbreaks, including differences between outbreaks linked to cheese made from pasteurized versus unpasteurized milk. RESULTS During 1998-2011, 90 outbreaks attributed to cheese were reported; 38 (42%) were due to cheese made with unpasteurized milk, 44 (49%) to cheese made with pasteurized milk, and the pasteurization status was not reported for the other eight (9%). The most common cheese-pathogen pairs were unpasteurized queso fresco or other Mexican-style cheese and Salmonella (10 outbreaks), and pasteurized queso fresco or other Mexican-style cheese and Listeria (6 outbreaks). The cheese was imported from Mexico in 38% of outbreaks caused by cheese made with unpasteurized milk. In at least five outbreaks, all due to cheese made from unpasteurized milk, the outbreak report noted that the cheese was produced or sold illegally. Outbreaks caused by cheese made from pasteurized milk occurred most commonly (64%) in restaurant, delis, or banquet settings where cross-contamination was the most common contributing factor. CONCLUSIONS In addition to using pasteurized milk to make cheese, interventions to improve the safety of cheese include limiting illegal importation of cheese, strict sanitation and microbiologic monitoring in cheese-making facilities, and controls to limit food worker contamination.
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Affiliation(s)
- L. Hannah Gould
- Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Elisabeth Mungai
- Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
- Atlanta Research and Education Foundation, Atlanta, Georgia
| | - Casey Barton Behravesh
- Division of Foodborne, Waterborne, and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
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Abstract
ABSTRACT
As the manufacture of cheese relies in part on the select outgrowth of microorganisms, such conditions can also allow for the multiplication of unwanted contaminants. Milk ultimately becomes contaminated with microorganisms originating from infection, the farm environment, and feedstuffs, as well as milking and processing equipment. Thus, poor sanitation, improper milk handling, and animal health issues can result in not only decreased yield and poor quality but also sporadic cases and outbreaks of dairy-related disease. The entry, establishment, and persistence of food-borne pathogens in dairy processing environments also present a considerable risk to products postprocessing. Food safety management systems coupled with regulatory policies and microbiological standards for milk and milk products currently implemented in various nations work to reduce risk while improving the quality and safety of cheese and other dairy products. With that, cheese has enjoyed an excellent food safety record with relatively few outbreaks of food-borne disease considering the amount of cheese produced and consumed worldwide. However, as cheese production and consumption continue to grow, we must remain vigilant in ensuring the continued production of safe, high-quality cheese.
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Dagostin JLA, Carpine D, Masson ML. Influence of Acidification Method on Composition, Texture, Psychrotrophs, and Lactic Acid Bacteria in Minas Frescal Cheese. FOOD BIOPROCESS TECH 2012. [DOI: 10.1007/s11947-012-1029-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ganesan B, Irish DA, Brothersen C, McMahon DJ. Evaluation of microbial survival post-incidence on fresh Mozzarella cheese. J Dairy Sci 2012; 95:6891-6. [PMID: 23063153 DOI: 10.3168/jds.2012-5390] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 08/17/2012] [Indexed: 11/19/2022]
Abstract
Commercial fresh Mozzarella cheese is made by direct acidification and is stored dry or in water without salt addition. The cheese has a shelf life of 6 wk, but usually develops an off-flavor and loses textural integrity by 4 wk, potentially due to the lack of salt and high moisture that allow the outgrowth of undesirable bacteria. To understand how microbial incidence affects cheese quality and how incident pathogen-related bacteria are limited by salt level during refrigerated storage, we made fresh Mozzarella cheese with high (2%) and low (0.5%) salt. The high-salt cheese was packaged and stored dry. The low-salt cheese was packaged and stored either dry or in 0.5% salt brine. One portion of cheeses was evaluated for surviving incident microbes by aerobic plate counts, coliform counts, and psychrophilic bacterial counts, of which coliforms and psychrophiles were not detected over 9 wk. Aerobic plate counts remained at 100 to 300 cfu/g up to 2 wk but increased by 1,000- to 10,000-fold between 4 and 6 wk at all salt levels and storage conditions. Other portions of cheeses were inoculated with either Escherichia coli or Enterococcus faecalis, both of which increased by 100-fold over 90 d of storage. Interestingly, E. coli added to the cheese brine first grew in the brine by 100-fold before attaching to the cheese, whereas Ent. faecalis attached to the cheese within 24h and grew only on the cheese. We conclude that incident bacteria, even from similar environments, may attach to cheese curd and survive differently in fresh Mozzarella cheese than in brine. Overall, 2% salt was insufficient to control bacterial growth, and slow-growing, cold- and salt-tolerant bacteria may survive and spoil fresh Mozzarella cheese.
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Affiliation(s)
- Balasubramanian Ganesan
- Dairy Technology and Innovation Laboratory, Western Dairy Center, Department of Nutrition, Dietetics and Food Sciences, Utah State University, Logan, Utah 84322, USA.
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LEGGETT L, TOMASULA P, VAN HEKKEN D, PORTO-FETT A, SHOYER B, RENYE J, LUCHANSKY J, FARKYE N. EFFECT OF STORAGE AT 4 AND 10C ON THE GROWTH OF LISTERIA MONOCYTOGENES IN AND ON QUESO FRESCO*. J Food Saf 2012. [DOI: 10.1111/j.1745-4565.2012.00373.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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26
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Brooks JC, Martinez B, Stratton J, Bianchini A, Krokstrom R, Hutkins R. Survey of raw milk cheeses for microbiological quality and prevalence of foodborne pathogens. Food Microbiol 2012; 31:154-8. [PMID: 22608218 DOI: 10.1016/j.fm.2012.03.013] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 02/17/2012] [Accepted: 03/25/2012] [Indexed: 11/17/2022]
Abstract
Cheese may be manufactured in the United States using raw milk, provided the cheese is aged for at least 60 days at temperatures not less than 35°F (1.7°C). There is now increased concern among regulators regarding the safety of raw milk cheese due to the potential ability of foodborne pathogens to survive the manufacturing and aging processes. In this study, 41 raw milk cheeses were obtained from retail specialty shops, farmers' markets, and on-line sources. The cheeses were then analyzed for the presence of Listeria monocytogenes, Salmonella, Escherichia coli O157:H7, Staphylococcus aureus, and Campylobacter. Aerobic plate counts (APC), coliform and yeast/mold counts were also performed. The results revealed that none of the enteric pathogens were detected in any of the samples tested. Five samples contained coliforms; two of those contained E. coli at less than 10(2) cfu/g. Three other cheese samples contained S. aureus. The APC and yeast-mold counts were within expected ranges. Based on the results obtained from these 41 raw milk cheeses, the 60-day aging rule for unpasteurized milk cheeses appears adequate for producing microbiologically safe products.
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Affiliation(s)
- J C Brooks
- Department of Food Science and Technology, University of Nebraska-Lincoln, 338 Food Industry Complex, Lincoln, NE 68583-0919, USA
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Costa Sobrinho PDS, Marçal de Faria CA, Silva Pinheiro J, Gonçalves de Almeida H, Vieira Pires C, Silva Santos A. Bacteriological Quality of Raw Milk Used for Production of a Brazilian Farmstead Raw Milk Cheese. Foodborne Pathog Dis 2012; 9:138-44. [DOI: 10.1089/fpd.2011.1010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Paulo de Souza Costa Sobrinho
- Department of Nutrition, Federal University of Jequitinhonha and Mucuri Valleys (UFVJM), Diamantina, Minas Gerais, Brazil
| | | | - Julia Silva Pinheiro
- Department of Nutrition, Federal University of Jequitinhonha and Mucuri Valleys (UFVJM), Diamantina, Minas Gerais, Brazil
| | - Héllen Gonçalves de Almeida
- Department of Nutrition, Federal University of Jequitinhonha and Mucuri Valleys (UFVJM), Diamantina, Minas Gerais, Brazil
| | - Christiano Vieira Pires
- Federal University of São João del-Rei, Campus Sete Lagoas, Sete Lagoas, Minas Gerais, Brazil
| | - Aline Silva Santos
- Department of Nutrition, Federal University of Jequitinhonha and Mucuri Valleys (UFVJM), Diamantina, Minas Gerais, Brazil
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Retureau É, Callon C, Didienne R, Montel MC. Is microbial diversity an asset for inhibitingListeria monocytogenesin raw milk cheeses? ACTA ACUST UNITED AC 2010. [DOI: 10.1051/dst/2010010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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29
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O'Brien M, Hunt K, McSweeney S, Jordan K. Occurrence of foodborne pathogens in Irish farmhouse cheese. Food Microbiol 2009; 26:910-4. [DOI: 10.1016/j.fm.2009.06.009] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 06/17/2009] [Accepted: 06/20/2009] [Indexed: 11/24/2022]
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