Bacterial Dynamics During the Processing of Nuodeng Dry-cured Ham

To study the community composition and dynamics of bacteria in Nuodeng dry-cured ham,16S rRNA gene V₃-V₄ region of interior bacteria of the ham during the curing,drying,fermentation,and maturation stages were amplified and sequenced via high-throughput sequencing technology. The diversity of bacterial community and its correlation with the physicochemical properties of ham have been analyzed. The results showed that there was the highest bacterial diversity in the ham at the curing stage. Firmicutes,Proteobacteria,Actinobacteria,Bacteroidetes and other bacteria were the dominant bacteria in the whole fermentation process. Staphylococcus,Psychrobacter,Pseudomonas and other bacteria were distributed in the four processing stages. The highest abundance in the entire processing was Staphylococcus. Moisture content had the greatest impact on the bacterial community during the curing stage,and the moisture content in the maturation stage dropped to about 33.4%. The salt content had the most obvious effect on the samples of the drying and fermentation stages in which Staphylococcus and the salt content was significantly positively correlated,and the salt content in the maturation stages increased to about 6.7%.The pH and free amino acid content were the most correlated with the samples of the maturation stages. The pH in this stage was about 6.05,and the free amino acid content reached to 1.86%. This research provided reference data for the study of microbial influence on the characteristic properties of Nuodeng ham and the development of starter culture that can improve the quality and fermentation efficiency of fermented meat products.