Skip to main content
ARS Home » Plains Area » Clay Center, Nebraska » U.S. Meat Animal Research Center » Meat Safety and Quality » Research » Publications at this Location » Publication #419606
Research Project: Holistic Tactics to Advance the Microbiological Safety and Quality of the Red Meat Continuum

Location: Meat Safety and Quality

Title: Recovered bacteria associated with gas accumulation of vacuum-packaged fresh kosher ground beef stored at refrigeration temperature

Author
item Kalchayanand, Norasak
item KOOHMARAIE, MOHAMMAD - Institute Of Environmental Health Laboratories And Consulting Group
item Wheeler, Tommy

Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/17/2025
Publication Date: 4/22/2025
Citation: Kalchayanand, N., Koohmaraie, M., Wheeler, T.L. 2025. Recovered bacteria associated with gas accumulation of vacuum-packaged fresh kosher ground beef stored at refrigeration temperature. Journal of Food Protection. 88(5). Article 100493. https://doi.org/10.1016/j.jfp.2025.100493.
DOI: https://doi.org/10.1016/j.jfp.2025.100493

Interpretive Summary: Vacuum-packaging and storage conditions at chilled temperatures are commonly used in order to prolong the shelf life of meat. Under these conditions, these cold-tolerant spoilage microorganisms not only can grow but the conditions are more favorable for their growth because these conditions eliminate competition from other microorganisms. The objective of this study was to isolate and identify bacteria that caused gas formation and accumulation in vacuum-packaged refrigerated fresh kosher ground beef and from environmental plant samples. Gas accumulation and slight off-odor was detected after 5 d storage at refrigerated temperatures. A variety of bacteria at various levels were detected and identified after 5 and 56 days of refrigerated storage. Based on the results from the present study, the potential bacteria responsible for gas accumulation and distention of the vacuum-packaged ground beef as well as hydrogen sulfide gas production were identified and can be targeted to reduce the incidence of fresh kosher ground beef spoilage.

Technical Abstract: 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), psy-chrotrophic bacteria (PSYB), Enterobacteriaceae (EB) increased by 0.58–1.09 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 (H2S) 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 postpackaging.