Abstract:

Bacterial strains were isolated and identified from bacteria-fermented lobster sauce samples collected from 10 producing areas in Guizhou province. Through the experiments of pure fermentation, sensory evaluation, determination of protease-producing activity and aerogenesis test, this study aimed to screen non-anaerogenic Bacillus strains that have high protease-producing activity and good flavor and can replace the bacterial strains in spontaneous fermentation of lobster sauce. As a result, 3 strains (BJ3-2, BJ1-3 and ZY4-5) with prominent fermentation quality are screened out from 184 strains of Bacillus, whose protease -producing activities (h/c) are 3.60, 1.71 and 1.50 respectively. The physiological and biochemical identification and the 16S rDNA analysis showed that they belong to Bacillus subtilis. Moreover, the enlarged pure fermentation experiment proved that BJ3-2, BJ1-3 and ZY4-5 may be taken as the reference strains for industrial fermentation

Key words: bacteria-fermented lobster sauce, Bacillus, pure fermentation, protease, isolation and identification