| Actinomucor elegens and Rhizopus oligosporus are used in sufu manufacture. In view of fermentation control, mycelial growths of both strains were tested for sensitivity to fluctuations of temperature and water activity. This was obtained by measuring radial growth as well as biomass dry weight of pre-germinated microcolonies on defined media. The optimum growth conditions of A. elegens and R. oligosporus were temperature 25?00C and 35--400C, a~ 0.98?.99 and 0.99 respectively. The result indicates that R. oligosporus could be used in the sufu production in a hot summer.The changes of microflora of a sufu production were studied throughout the sufu processing period (tofu, pehtze, salted pehtze, and the ageing stage). Total count of mesophilic aerobic bacteria (TMAB), lactic acid bacteria (LAB), Enterobacteriaceae (Enterob.) , yeast and moulds (fungi), were detected by using the selective media of PCA, MRS, VRBG, and OGYE respectively. The microorganisms tested reached the highest levels during the preparing pehtze stage, and then fungi and Enterob. were decreased rapidly during the consequent steps. But the TMAB kept at a certain level after a slight decrease. LAB appeared a complicated situation, which was strongly affected by the salt concentration. As the result of propagation of LAB, Low-salt sample spoiled, yet the higher wasn affected so apparent. As a whole, microorganisms closely related to sufu flavor and quality due to their abilities of degrading protein and lipid. It is significant to connect the changes of microflora in sufu with it biochemical changes in a sufu production for improving sufu production and developing new product.
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