Diversity of mesophilic and psychrophilic proteolytic bacteria in different minced meat samples

Since minced meat provides a large contact surface, it is a food in which the total bacterial load and the enzymatic profiles of the species that make up this load should be addressed, even in cases where it does not contain pathogens. Therefore, this study aimed to investigate the effect of freezing, one of the most commonly used storage methods for minced meat, on total and proteolytic bacterial loads. To simulate the actual storage process, individuals belonging mainly to the genera Bacillus, Serratia, Pseudomonas, Citrobacter, Acinetobacter, and Escherichia were isolated from the samples examined directly and after 15 days of freezing, without any process that would cause a change in the microbial load. 71.11% of these isolates exhibited valine and cystine aminopeptidase activity, while 37.77 and 33.33% exhibited trypsin and α-chymotrypsin activity, respectively. In addition, the results show that cryopreservation allows psychrophilic proteolytic bacteria to increase their numbers in meat.