Whole-genome annotation and functional profiling of Pediococcus acidilactici RM1 and its effects on physicochemical characteristics, volatile flavor profiles, and microbial diversity in dry-cured chicken legs.

Abstract

The aim of this study was to evaluate the application potential of Pediococcus acidilactici RM1 (GenBank: PQ669089), isolated from Chinese traditional dry sausages, for dry-cured chicken legs, focusing on physicochemical quality, non-volatile taste compounds and volatile flavor compounds, and microbial diversity. Whole-genome sequencing demonstrated that RM1 lacks virulence factors (such as hemolysins), common antibiotic-resistance genes and biogenic amine-related decarboxylase genes. Functional annotation uncovered core genes involved in proteolysis, amino acid catabolism, lipolysis, fatty acid and carbohydrate metabolism. Compared with the control, P. acidilactici inoculation significantly (P < 0.05) decreased pH, water activity (aw), nitrite content, and the total viable bacterial count of dry-cured chicken legs from 5.84 ± 0.05, 0.72 ± 0.01, 2.94 ± 0.10 mg/kg and 4.96 ± 0.07 log10 CFU/g to 5.71 ± 0.01, 0.69 ± 0.01, 2.22 ± 0.16 mg/kg and 3.77 ± 0.18 log10 CFU/g, respectively. Higher redness (a*), degree of protein hydrolysis, total volatile basic nitrogen (TVB-N), and carbonyl values were observed in the inoculated group. The contents of creatine and glutamic acid significantly increased by 24.5% and 25.5%, respectively in the inoculated group. Inoculation elevated relative proportions of alcohols, ketones and pyrazines, yet reduced the relative abundances of Ligilactobacillus, Lactobacillus and Kineothrix. Collectively, P. acidilactici RM1 reshaped microbial community and improved volatile flavor profiles of dry-cured chicken legs.