Abstract: By separating bacteria from the steep juice of fermented bean curd of strong odour(FBCSO), two bacterial specieshave acquired. They were classified into Coccus and Bacillus according to the morphology, and tentatively determined asNeisseria and Bacillus circulans by means of separate, purification and identification. Based on the traditional craft processtechnology of FBCSO, this paper has studied the factors that affect the flavor of FBCSO. These factors are bacterial species,fermented time, inoculating amount, cultivate temperature and carbon source. The optimum fermented parameters have thenbeen acquired. Namely, the ratio of the Bacillus circulans to Neisseria in the steep liquid was 1:2, the inoculating amount 4%, theadditive amount of rice flour and table salt 1% and 0.5%, respectively, the optimum temperature 30℃ and the cultural time 4～5 days. Under these conditions the FBCSO has shown good flavor and quality.

Key words: fermented bean curd of strong odour, bacterial strain, separate and purify, identification