Changes of Bacterial Communities in Myeolchi-jeot, Fermented Anchovy, during Fermentation

Abstract

To investigate microbial communities of myeolchi-jeot, made by the fermentation of highly salted [approximately 25% (w/v)] anchovy in Korea, three sets of myeolchi-jeot samples were prepared using anchovy (Engraulis japonicas) with different sizes and their bacterial abundances, pH, and bacterial communities were analyzed during 280 days. The pH profiles were significantly different depending on myeolchi-jeot samples. Bacterial community analysis using pyrosequencing revealed that Photobacterium, Vibrio, and Psychrobacter were dominant at the beginning of the fermentation and the bacterial communities were significantly different depending on myeolchi-jeot samples during the early fermentation period, but eventually members of Tetragenococcus, halophilic lactic acid bacteria, became predominant. During the early fermentation period, bacterial communities in myeolchi-jeot samples prepared by small size anchovy were dominated by different genera including Choromohalobacter, Salinivibrio, Staphylococcus, and Psychrobacter depending on samples, but the myeolchi-jeot samples prepared by large size anchovy were not predominated by specific genera. In conclusion, bacterial successions in myeolchi-jeot were different during the early fermentation period depending on anchovy size, but eventually Tetragenococcus became predominant in all myeolchi-jeot regardless of anchovy sizes during the late fermentation period.