Erin M Castelli, David L Campos, Andrea English, Kendra K Nightingale, Mindy M Brashears
{"title":"Using a Dose Response Approach on the Growth of Food Borne Pathogens in Feces of Cattle Fed Three Different Direct-Fed Rations Reveals the Efficacy of Lactobacillus salivarius L28.","authors":"Erin M Castelli, David L Campos, Andrea English, Kendra K Nightingale, Mindy M Brashears","doi":"10.1016/j.jfp.2025.100502","DOIUrl":"https://doi.org/10.1016/j.jfp.2025.100502","url":null,"abstract":"<p><p>In the past two decades, the use of probiotics in livestock production has significantly increased. Direct-fed microbials (DFMs) have become popular in beef cattle production due to consumer demand for more natural meat alternatives. The objectives of this study were to 1) evaluate the dose-response of L28 at concentrations of 6, 7, and 8 log CFU/mL to inhibit the growth of STEC and S. enterica in cattle manure, and 2) assess tylosin and monensin in cattle manure and the efficacy of L28 in pathogen inhibition.Fecal samples were collected from cattle fed three different rations: 1.) monensin and tylosin (MONTY), 2.) monensin with L28 (MONPRO), and 3.) no L28, tylosin or monensin (BASE). Sterilized fecal samples were inoculated with a cocktail mixture of three Shiga toxin producing Escherichia coli (STEC) or Salmonella enterica (S. enterica) strains to an initial concentration of 3.0 - 4.0 log CFU/g. To evaluate the dose response, Lactobacillus salivarius (L. salivarius) L28 was applied at concentrations of 6, 7, and 8 log CFU/ml. ForS. enterica, the (BASE) ration had a significant treatment time effect at 12 h and 24 h with L28 at a dose of 8 log CFU (p = 0.01, p = 0.03). For STECs, the (BASE) had a similar effect, however not significant for 24 h (p = 0.7). A dose of 8 log CFU/mL reduced S. enterica growth in manure samples by 1.3 to 4.2 log CFU/g compared to BASE. While L. salivarius does not completely prevent bacterial growth, it effectively reduces foodborne pathogens. Using L. salivarius in beef products offers a natural alternative to antibiotics, benefiting both consumers and the beef industry.</p>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":" ","pages":"100502"},"PeriodicalIF":2.1,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143743022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A E Asmus, K M Heimer, K W Davis, P M Ferm, K E Belk, R S Singer, T J Johnson, N R Noyes
{"title":"Temporality and genetic relatedness of Salmonella in a pork processing facility.","authors":"A E Asmus, K M Heimer, K W Davis, P M Ferm, K E Belk, R S Singer, T J Johnson, N R Noyes","doi":"10.1016/j.jfp.2025.100500","DOIUrl":"https://doi.org/10.1016/j.jfp.2025.100500","url":null,"abstract":"<p><p>The goal of this study was to investigate the prevalence and genetic relatedness of Salmonella enterica in meat and contact surfaces from two processing lines at a pork processing plant over a commercial production schedule. Across 192 samples, there was no significant difference in Salmonella prevalence between Bootjack Trim (BJ) and Boston Butt Trim (BBT) meat (11.5% vs. 11.5%, P = 1.0), though prevalence was higher in meat than on contact surfaces for both the BJ (11.5% vs. 0%, P = 0.01) and BBT (11.5% vs. 3.1%, P = 0.08) processing lines. Both Salmonella prevalence and identified serotypes clustered within four distinct processing windows that spanned multiple dates and processing lines. Phylogenetic analysis using core single nucleotide polymorphisms (SNPs) identified a highly related Salmonella I4,[5],12:i:- strain (N = 33, 0 - 2 SNPs difference across all isolates) in both the BJ and BBT lines, persisting over consecutive days within one processing window. Similarly, a highly related Salmonella London strain (N = 18, 0 - 1 SNPs) was found across both processing lines on three processing dates that spanned 28 days. Additional highly related strains of Salmonella Typhimurium (N = 8, 0 - 1 SNPs) and Salmonella Agona (N = 7, 0 - 3 SNPs) were also detected across multiple dates. Strains of S. I4,[5],12:i:- and S. London were genetically distinct (>30 SNPs) from publicly available genomes from isolates obtained from other pork processing plants located in the Upper Midwest. Overall, findings suggested that Salmonella prevalence varies across processing lines and production schedules. However, the high phylogenetic relatedness among the Salmonella serotypes suggests a common source may have been present prior to each primal cut being processed into subprimal cuts.</p>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":" ","pages":"100500"},"PeriodicalIF":2.1,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143743017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Survivability of Escherichia coli O157:H7 ATCC 43888 and Enterococcus faecium ATCC 8459 in a Hydrocolloid Gel Bar Model and Macronutrient Bar Model in Response to Vacuum Microwave Drying and Storage.","authors":"Dominique Pacitto-Reilly, Genevieve Flock","doi":"10.1016/j.jfp.2025.100499","DOIUrl":"https://doi.org/10.1016/j.jfp.2025.100499","url":null,"abstract":"<p><p>This study aimed to investigate the microbial safety of Vacuum Microwave Drying (VMD) and 30 days storage at 25°C on survivability of Escherichia coli O157:H7 ATCC 43888 and Enterococcus faecium ATCC 8459 in a nutritionally minimal bar model and macronutrient bar model. Sodium alginate hydrocolloid gel bars were inoculated with each microorganism and underwent processing in a 2 kW VMD and subsequent storage at 25°C for 10 days in sealed bags to determine the impact of VMD on bacteria without the influence of a nutritionally dense food matrix. Additionally, effects of macronutrient concentration on organism survivability during processing and storage were tested using a peanut butter banana bar formulated to contain high carbohydrate, high protein, or high fat content. The macronutrient bars were inoculated with each microorganism and underwent VMD with subsequent storage at 25°C for up to 30 days in sealed bags. Results of the hydrocolloid gel model showed that in a nutritionally minimal food matrix, both microorganisms were susceptible to VMD with additional loss of each microorganism during storage. Results showed entire loss of E. coli O157:H7 by day 10 of storage. In the macronutrient bar study, E. faecium had minimal susceptibility to VMD and storage at 30 days while E. coli O157:H7 had minimal susceptibility to VMD with greater susceptibility to storage for 30 days. There was a significant difference (p<0.05) in log loss comparing E. coli O157:H7 VMD processed and unprocessed bars and minimal significance comparing E. faecium VMD processed and unprocessed bars. Water activity and moisture content at storage timepoints had no observed correlation with pathogen survivability in either study.</p>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":" ","pages":"100499"},"PeriodicalIF":2.1,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143743013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Karla M Acosta, Alberto A Beiza, Isabella Raschke, Zhihong Lin, Juan M Madera, Mary Dawson, Zenaida Aguirre-Muñoz, Sujata A Sirsat
{"title":"Synthesis and Effectiveness of a Novel Food Safety Toolkit for Low-Literacy Novice Food Handlers.","authors":"Karla M Acosta, Alberto A Beiza, Isabella Raschke, Zhihong Lin, Juan M Madera, Mary Dawson, Zenaida Aguirre-Muñoz, Sujata A Sirsat","doi":"10.1016/j.jfp.2025.100496","DOIUrl":"https://doi.org/10.1016/j.jfp.2025.100496","url":null,"abstract":"<p><p>The state of Texas announced a requirement for all foodservice employees to pursue an American National Standards Institute (ANSI) certified food handler training in September 2016. However, the effectiveness of ANSI-certified food safety training for low-literacy novice food handlers has not been investigated. Low-literacy novice food handlers are those who have some familiarity with the field but may not have the literacy level or may have a language barrier that is as an obstacle to completing the training and/or certification. This study aimed to develop a novel food safety training toolkit (NTK) as a supplementary resource to existing ANSI-certified training tools and evaluate its effectiveness in improving food handlers' knowledge retention and certification. To achieve this, a mixed-method study was conducted. For the first part of the research, one-on-one interviews were conducted with foodservice stakeholders (managers, sanitarians, owners) to identify the gaps and needs that exist in the current food safety training system. In the second part of the research, NTK was synthesized and designed with clear illustrations and drawings based on previous education and training literature. A between-subjects experiment was conducted to assess the effectiveness of NTK on food handlers' food safety knowledge. Results showed that the participants' overall food safety knowledge significantly increased due to NTK when compared to the control group. This study is distinctive because it directly responds to the needs of the foodservice industry, and the study output (NTK) can serve as the cornerstone to fill the gap in current food safety training for low-literacy or novice food handlers in the future.</p>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":" ","pages":"100496"},"PeriodicalIF":2.1,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143730343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Erika Rene Blickem , Jon W. Bell , Mona Baumgartel , John DeBeer
{"title":"USDA Food Recalls for the Period 2012–2023 Compared with FDA Regulated Food Recalls Over the Past Two Decades","authors":"Erika Rene Blickem , Jon W. Bell , Mona Baumgartel , John DeBeer","doi":"10.1016/j.jfp.2025.100492","DOIUrl":"10.1016/j.jfp.2025.100492","url":null,"abstract":"<div><div>This manuscript evaluates recalls of food products that are regulated by the United States Department of Agriculture (USDA), Food Safety and Inspection Service (FSIS). The FSIS regulates food products made from animals raised on farms including beef, pork, poultry, buffalo, and venison, as well as some egg products and farmed or wild-caught seafood of the order of Siluriformes (catfish). During the 12-year period of 2012–2023, 1,001 food recall incidents occurred representing 205.2 million lbs of recalled product. These recall incidents were classified by the FSIS at 76% as Class I, 20% as Class II, and 4% as Class III. The causes of the recalls were combined for this analysis into three master categories: Product Contaminants, Processing Issues, and Other Reasons. Product Contaminants caused of 68% of the FSIS recalls, Processing Issues added 13%, and Other Reasons contributed 19%. Further evaluation of these recall incidents by product type resulted in Poultry at 29%, Beef at 23%, Mixed Animal meat at 23%, and Pork at 22% of the recall incidents. Evaluation of these recalls by product weight showed Mixed Animal meat at 52%, Poultry at 27%, Beef at 16%, and Pork at 4%. Biological Contamination was a component of the Products Contaminants master category, and 4 bacterial species caused almost 59% of the FSIS recalls by weight. <em>Listeria monocytogenes</em> caused 32%, Shiga toxin-producing <em>E. coli</em> (STEC) caused 12%, <em>Salmonella</em> serovars caused 9%, and <em>Bacillus cereus</em> caused 0.5% of these recalls by weight. These FSIS food recalls were compared to the FDA Food & Beverage recalls from a recent publication. <em>Listeria</em> was the common cause of the highest percentage for the FDA recalled by incidents and FSIS recalls by weight. Most of the food recalls were caused by human error. Developing a strong Food Safety Culture along with strong cleanup and sanitation procedures is imperative to minimizing and preventing food recalls.</div></div>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":"88 5","pages":"Article 100492"},"PeriodicalIF":2.1,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
YeonJin Jung, Gabriella Pinto, Gustavo Reyes, Chenhao Qian, Martin Wiedmann, Matthew J Stasiewicz
{"title":"A critical review of parameters relevant for Shiga toxin-producing Escherichia coli and Listeria monocytogenes risk assessments of leafy greens.","authors":"YeonJin Jung, Gabriella Pinto, Gustavo Reyes, Chenhao Qian, Martin Wiedmann, Matthew J Stasiewicz","doi":"10.1016/j.jfp.2025.100497","DOIUrl":"https://doi.org/10.1016/j.jfp.2025.100497","url":null,"abstract":"<p><p>In the past decade, several quantitative models and risk assessments for Shiga toxin-producing Escherichia coli (STEC) and Listeria monocytogenes have been developed to guide the management of these pathogens in fresh produce. However, there is a need to collect and critically review the parameters used to guide their potential reuse in future risk assessments. This review (i) identifies 11 and 7 recently published quantitative models and risk assessments for STEC and L. monocytogenes, respectively, in leafy greens, (ii) summarizes parameters, and (iii) reviews the underlying data sources or mathematical formulas used. A total of 80 key parameters (55 and 25 for STEC and L. monocytogenes, respectively, 10 shared) were extracted from the reviewed models across five supply chain stages, including: Preharvest, Harvest, Processing, Presentation to Consumer (Retail or Foodservice Locations), and Consumer Handling. Primary growth, secondary growth, and dose-response equations and parameters for STEC and L. monocytogenes were also extracted. Additional literature reviews were performed if (i) certain key parameters were based on a single or a few data sources or (ii) key parameters were identified in a supply chain stage for one pathogen, but missing from the other. The critical summaries of parameters presented here (i) provide a resource for future risk assessments, (ii) help define future data collection needs, and (iii) represent a starting point for similar reviews focusing on other produce commodities and pathogens.</p>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":" ","pages":"100497"},"PeriodicalIF":2.1,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143730337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cheryl M Armstrong, Chin-Yi Chen, Yicheng Xie, Javier Atencia, Sophie Pierre, Yiping He, Joe Lee, Gretchen Dykes, Kathleen Johnson, Brice Froment, Sean Martinos, Joseph Capobianco
{"title":"Quantification of Salmonella in raw poultry using Droplet Digital PCR with a Whole Cell, Enrichment-free Approach.","authors":"Cheryl M Armstrong, Chin-Yi Chen, Yicheng Xie, Javier Atencia, Sophie Pierre, Yiping He, Joe Lee, Gretchen Dykes, Kathleen Johnson, Brice Froment, Sean Martinos, Joseph Capobianco","doi":"10.1016/j.jfp.2025.100498","DOIUrl":"https://doi.org/10.1016/j.jfp.2025.100498","url":null,"abstract":"<p><p>Salmonella contamination in poultry remains a persistent public health challenge, despite ongoing regulatory efforts to reduce its presence. Traditional culture-based enrichment methods commonly employed for detecting Salmonella have inherent limitations, such as biases in bacterial growth and inaccurate quantification of initial contamination levels. This study introduces an enrichment-free approach for quantifying Salmonella in raw poultry, utilizing the Pathotrak system for bacterial separation and concentration, followed by Droplet Digital PCR (ddPCR) for absolute quantification. Our findings highlight that whole-cell preparations within ddPCR droplets yield significantly higher detection efficiency compared to extracted DNA, likely due to the reduced loss of genetic material during processing. The method was validated by correlating theoretical inoculation levels with ddPCR measurements, resulting in a strong linear relationship (R<sup>2</sup> = 0.903) and a slope of 0.99, indicating high accuracy. Residuals from the regression model were normally distributed, confirming its validity. This platform offers a robust, rapid, and precise tool for detecting low levels of Salmonella in poultry products without enrichment, making it a more accurate and efficient approach to bacterial quantification in complex food matrices.</p>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":" ","pages":"100498"},"PeriodicalIF":2.1,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143730341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Allyson N Hamilton, Sarah L Jones, Christopher A Baker, Xinya Liang, Adam Siepielski, Ashlynn Robinson, Gayatri R Dhulappanavar, Kristen E Gibson
{"title":"A Systematic Review and Meta-Analysis of Chemical Sanitizer Efficacy Against Biofilms of Listeria monocytogenes, Salmonella enterica, and STEC on Food Processing Surfaces.","authors":"Allyson N Hamilton, Sarah L Jones, Christopher A Baker, Xinya Liang, Adam Siepielski, Ashlynn Robinson, Gayatri R Dhulappanavar, Kristen E Gibson","doi":"10.1016/j.jfp.2025.100495","DOIUrl":"https://doi.org/10.1016/j.jfp.2025.100495","url":null,"abstract":"<p><p>Chemical sanitizers are applied to food processing surfaces to inactivate bacterial pathogens. Pathogen type, surface type along with sanitizer type, concentration, and contact time are important factors potentially impacting sanitation efficacy. Numerous studies on chemical agents and lab-generated biofilms have been published; however, cross-study comparisons can be difficult. A systematic literature review (SLR) and meta-analysis was conducted to evaluate chemical sanitizer efficacy against Listeria monocytogenes, Salmonella spp., and Shiga toxin-producing Escherichia coli (STEC) within lab-generated biofilms on food contact surfaces (FCS). The SLR included 13 peer-reviewed articles published between 2000 and 2020. Sanitizer concentration, type, contact time, surface type, and bacteria type were explored using multi-level mixed effects models to determine their impact on bacterial log reduction on FCS. The overall estimated log reduction was 2.90 (effect size [ES]) with a 95% CI = 2.40, 3.39 (p<0.0001). The multi-level mixed effects model estimated log reductions of 2.67 to 3.82 for peracetic acid (PAA), quaternary ammonium compounds, sodium hypochlorite, hydrogen peroxide+PAA, and calcium hypochlorite, with significant differences across sanitizers. No significant differences were found between L. monocytogenes and STEC; however, both pathogens were significantly different from Salmonella spp. All pathogens were significant predictors of mean log reduction (p<0.0001). No significant differences were found between surface types, while all were significant predictors of mean log reduction (p<0.0001). Neither sanitizer concentration (p=0.5554) nor sanitizer contact time (p=0.1800) were found to be significant predictors of estimated mean log reduction. These findings highlight the importance of specific sanitizers and tailored approaches based on surface types and pathogen considerations.</p>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":" ","pages":"100495"},"PeriodicalIF":2.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143692420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Recent Advances in Metabolomic Research Within Food Mycology","authors":"Wanchong He","doi":"10.1016/j.jfp.2025.100494","DOIUrl":"10.1016/j.jfp.2025.100494","url":null,"abstract":"<div><div>In food science, fungi demonstrate a paradoxical role: some species contribute positively by improving food’s flavor, aroma, and texture, while others undermine food safety and quality, leading to spoilage or contamination through the production of harmful mycotoxins. When fungi colonize food materials, they produce distinct chemical profiles consisting of both primary and secondary metabolites. Metabolomics, a field dedicated to the analysis of small molecular compounds within biological entities, offers valuable insights into fungal metabolic activities and their impact on food safety and quality. This paper explores recent progress in applying metabolomics to investigate fungi within food systems, focusing on the complex interactions between fungi and their environments. Additionally, it identifies promising directions for advancing research in this rapidly evolving domain.</div></div>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":"88 5","pages":"Article 100494"},"PeriodicalIF":2.1,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143691832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Norasak Kalchayanand, Mohammad Koohmaraie, Tommy L Wheeler
{"title":"Recovered Bacteria Associated with Gas Accumulation in Vacuum-Packaged Fresh Kosher Ground Beef Stored at Refrigeration Temperature.","authors":"Norasak Kalchayanand, Mohammad Koohmaraie, Tommy L Wheeler","doi":"10.1016/j.jfp.2025.100493","DOIUrl":"https://doi.org/10.1016/j.jfp.2025.100493","url":null,"abstract":"<p><p>Vacuum packaging and storage at chilled temperatures are commonly used to prolong the shelf life of meat. Under these conditions, cold-tolerant facultatively anaerobic spoilage microorganisms not only can grow but the conditions are more favorable for their growth because these conditions eliminate competition from cold-tolerant aerobic microorganisms. The objective of this study was to identify bacteria that caused gas formation and accumulation in vacuum-packaged refrigerated fresh kosher ground beef as well as from processing plant environment samples. A total of 87 vacuum-packaged ground beef (∼454 g size) and 33 environmental samples were received from a kosher processing plant. The initial populations of aerobic bacteria (AB), psychrotrophic bacteria (PSYB), Enterobacteriaceae (EB) increased 0.58 to 1.09 log CFU/g, while the population of lactic acid (LAB) increased 3.18 log CFU/g after 5d at 2-4°C. After 5 d storage at 2-4°C, 34% of the packages exhibited gas accumulation. The accumulated gas reacted with lead acetate and formed a brown-black color indicating hydrogen sulfide (H<sub>2</sub>S) formation, and the ground beef had a slight off-odor. Lactococcus lactis, Enterobacter cloacae, and Klebsiella oxytoca were the most isolated from environmental samples. Based on the results from the present study, the potential bacteria responsible for gas accumulation and distention of the vacuum-packaged ground beef were Leuconostoc mesenteroides (LAB), Lactobacillus curvatus (LAB), and Serratia liquefaciens (EB). The bacterial strains isolated from 5 d storage distended packages after 5 d storage were dominantly LAB, while the bacterial strains isolated after 56 d storage were mainly EB. These results indicated that LAB are potentially responsible for gas formation that occurs early post-packaging.</p>","PeriodicalId":15903,"journal":{"name":"Journal of food protection","volume":" ","pages":"100493"},"PeriodicalIF":2.1,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143692235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}