Effect of homo‐ and hetero‐fermentative lactic acid bacteria on physicochemical properties, amino acid, and volatile flavor compounds during paocai fermentation by pure culture
This study investigated the physicochemical properties, amino acid, and volatile flavor compounds of paocai inoculated with homo- (Lactobacillus pentosus NCU050008 and Lactobacillus plantarum NCU001290) and hetero-fermentative lactic acid bacteria (LAB) (Leuconostoc mesenteroides NCU018030 and Lactobacillus brevis NCU002227). The lactic acid, arginine, cysteine, cineole and (+)-3-carene mainly contributed to the characteristics of paoccai fermented inoculated with homo-fermentative LAB, while the acetic acid, proline, histidine, alanine, valine, leucine, isoleucine, glycine, phenylalanine, methionine and trans-3-caren-2-ol mainly contributed to the characteristics of paoccai fermented inoculated with hetero-fermentative LAB. Principal Component Analysis showed that the metabolism of paocai samples fermented inoculated with homo-fermentative LAB significantly differed from those in paocai with hetero-fermentative LAB. This study provides insights into the effects of homo- and hetero-fermentative lactic acid bacteria on the physicochemical properties, amino acid, and volatile flavor in paocai and might help for the industrial paocai production. Novelty Impact Statement: The results in this study showed the physicochemical properties, amino acid, and volatile flavor compounds of paocai inoculated with homo-fermentative lactic acid bacteria significantly differed from those of paocai inoculated with hetero-fermentative lactic acid bacteria (LAB) (Leuconostoc mesenteroides NCU018030 and Lactobacillus brevis NCU002227). Moreover, the characteristics compounds of paoccai fermented inoculated with homo-fermentative LAB were also differed from those of paoccai fermented inoculated with hetero-fermentative LAB. Therefore, the data obtained in this study provides a better understanding of the effects of homo-fermentative lactic acid and hetero-fermentative lactic acid bacteria on the paocai, and would be very beneficial for the production of high quality paocai.