Food safety aspects of dry-aged beef

Dry-aged beef has attracted attention, and recently has a legislative gap been filled through the introduction of a regulatory definition of dry aging. Nevertheless, the data available in the literature on food safety remain limited. In this context, this PhD Thesis aimed to expand knowledge on dry-aged beef, to provide an integrated assessment of microbiological safety. A critical review of the literature enabled the identification of the main knowledge gaps, which were further explored in this Thesis. First insights into dry-aged Holstein beef confirmed that, when processed in dedicated cabinets under controlled parameters, microbiological safety is preserved. The behavior of Listeria monocytogenes and Yersinia enterocolitica was evaluated during 60 days of dry aging, and the results showed that the growth of L. monocytogenes was not supported, whereas Y. enterocolitica was able to proliferate for up to 40 days in two batches. The evaluation of sampling depth for pH and water activity during the process highlighted the importance of the sampling method for the development of predictive models of microbial growth, which are currently insufficient to reproduce a growth curve comparable to the behavior of L. monocytogenes. The potential influence of trimming and portioning operations performed by Food Business Operators (FBOs) was evaluated, and the results demonstrated that operational conditions and processing practices affect the microbiological quality of the product. In conclusion, the results provide a contribution by helping to address and partially fill some of the main knowledge gaps, while offering useful information for FBOs and competent authorities. These findings support the improvement of Good Hygiene Practices and Good Manufacturing Practices, as well as the development of guidelines for their implementation and the definition of microbiological criteria dedicated to dry-aged meat, which are useful for risk assessment and for the regulatory harmonization of the process.