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Four the rebuild two natural villages bridges food Co., Ltd. production of \Sichuan is a must. \Has fermented bean curd production level is still relatively backward technology update is also quite slow. Workshop-style production model, is lagging far behind the development of the entire food industry standardization, standardization and security of the requirements. In this study, the fermented bean curd production, starting from these two strains of Mucor and Rhizopus, its culture conditions, the fermentation medium mixing ratio and other aspects of the exploration and in-depth study and carried out in a pilot for tofu further development of milk production to provide a theoretical basis and technical support. In the research of this subject, first, Mucor protease production culture conditions were optimized. Initial pH value of temperature, time, inoculum size, fermentation of four single-factor test based on four factors and three levels of response surface analysis and interaction of various factors significantly drawn Mucor optimal culture conditions: temperature of 27.57 ° C, 9.90% of the time 68.46h, inoculum size, fermentation medium initial pH value of 4.51, the protease activity of 152U. Secondly, on top of the the Rhizopus foundation fermentation medium Plackett-Burman design methods from wheat bran, casein peptone, olive oil, soybean powder, peptone, maltose, sucrose, glucose, MgSO4 · 7H2O of MgSO4,, KH2PO411 kinds of impact production glucoamylase live fermentation medium components screened out of three of the most important influencing factors, respectively, olive oil, casein Building, wheat bran, and come to reduce the olive oil content and increased casein peptone and wheat bran content to improve glycated enzyme activity are favorable; then approach the center of the response surface test steepest ascent experiments, the results show that the optimal center as olive oil 0.04%, 8.00% casein Building, wheat bran 4.00%; further Box-Behnken Design response surface analysis, there is a maximum point of the regression model, the olive oil 0.01%, 8.14% casein Building, wheat bran, 4.32%, the glucoamylase live for 18.7U than before. increased by 81%. Furthermore, Rhizopus as the original strain, in the four single-factor test temperature, time, inoculum size, fermentation medium initial pH value on the basis of four factors and three levels of response surface method various factors significantly analysis and interaction, and came to the conclusion Rhizopus glucoamylase production optimal culture conditions: temperature of 31.99 ℃, time 71.94h, 11.94% of the inoculum size, fermentation medium initial pH of 6.06, the glucoamylase activity was 24.39U. Then the Mucor and Rhizopus mixing ratio, exploration, to select mixing ratio by volume of 1,2 ︰ 1 ︰ 1,3 ︰ 1,4 ︰ 1,5 ︰ 1,6 ︰ 1 test, results showed that when the volume ratio for the detection of indicators of 2 ︰ 1 bean curd with good. Finally, in a pilot study results, every month of the indicators of the fermented bean curd track detection. The test results show that: of the tofu Baipi spray Mucor and Rhizopus mixed broth Aspergillus oryzae add in the accessories and add 12% salt, amino acid nitrogen content Sufu five months to reach 1.52g / 100g, water-soluble protein content of 13.52g/100g, total acid content 1.04g/100g, fermented bean curd hardness 124.6 g, coliform counts and aflatoxin B1 levels were lower than the safety limit.
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