This Is AuburnElectronic Theses and Dissertations

Maintaining Meat Quality through the Beef Supply Chain




Krikorian, Abigail

Type of Degree

Master's Thesis


Animal Sciences


The studies presented here were designed to evaluate the impacts of increased time periods during two key phases of the beef supply chain: pre-harvest transportation and post-processing storage. In the first study, the objective was to determine the relationship between gut microbial community and pathogen presences in cattle under different levels of transportation stress. Cattle were transported for either 2.5 or 12 hours, with samples collected before and after transportation to evaluate microbial shedding, microbiome, temperature, weight, and exit velocity. Under longer transportation, there was greater weight loss compared with short transportation along with a decrease in microbial diversity, which was associated with an increase in the fecal shedding of Escherichia coli. It is likely that long transportation times are associated with increased risks to food safety due to this dysbiosis. The second study objective was to determine the impacts of low temperature storage followed by secondary retail storages for long time periods on hamburger patty quality and shelf-life. Hamburger patties we packaged using modified atmosphere packaging and stored using a novel low temperature storage method for either 16, 20, or 30 days, after which they were kept in dark simulated retail storage for either 7, 10, or 14 days. Microbial growth fluctuated depending on storage time, but never exceeded acceptable limits. Similarly, the consensus of panelist’s sensory scores decreased especially under the retail storage time, but never below acceptable limits. Overall, using this storage regimen, the shelf-life of beef hamburger patties can be extended to at least 30 days without freezing. This thesis demonstrates that it is practical and beneficial to extend the storage time in post-processing phases but increasing the time in pre-processing phases may have negative impacts to the beef supply chain.