Impact of dry aging on quality parameters and microbiological safety of beef

The market of dry aged meat is rapidly increasing. However, few papers report the impact of specific dry aging parameters on quality and microbiological safety of dry aged meat. In this study we assessed the impact of a 90 days dry aging process, performed in a commercial cabinet, on the quality parameters and microbiological safety of Holstein beef loins. Meat pH, colour indexes and fatty acids were stable during the process. Main volatile compounds' concentration increased over time. Any oxidation of protein residues was detected and the main proteins undergoing proteolytic degradation early in the process were myoglobin, myofibrillar constituents and sarcoplasmic enzymes. The most significant histological changes started at 30 days and striation impairment was observed, not related to oxidative processes. The total bacteria count increased without signs of spoilage, Enterobacteriaceae were not enumerated and few reads of foodborne pathogens were detected by shotgun metagenomic. These results show that when the dry aging process is performed in a dedicated cabinet under strictly controlled process parameters, the microbiological safety of the meat is preserved. Our study provides the first insights of dry aged Holstein loins, whose valorisation would certainly enhance the economic, social and environmental sustainability of the Parmigiano Reggiano food system.