Bacterial diversity analysis of pork longissimus lumborum following long term ohmic cooking and water bath cooking by amplicon sequencing of 16S rRNA gene

The bacterial ecology of long term ohmic- (LTOH) and water bath- (WB) cooked pork longissimus lumborum during refrigerated storage was investigated by culture-dependent and amplicon sequencing of 16S rRNA gene. High bacterial diversity was observed in both LTOH- and WB-cooked meat, and the diversity decreased with prolonged storage, however, it was more complex in LTOH-cooked meat compared with WB treated ones. Bacillus, Pseudomonas, Enterococcus and Lactococcus were the most prevalent genera in the first two weeks and were replaced by Carnobacterium by the end of storage. Brevundimonas, Bacteroidaceae, Lactobacillaceae, uncultured Clostridiales Family_XIII, Alcaligenaceae and Micrococcales were more abundant in LTOH-cooked meat, while only Moraxellaceae were more abundant in WB-cooked samples. The different abundances may have resulted from the reaction of bacteria to different heating mechanisms. Overall, LTOH-cooked meat has a similar shelf-life with shorter processing time compared to WB treated ones.