| In the paper, soymilk was used to make soybean cheese by Roguefort cheese processing technology. Beany flavor removal methods were studied in this paper; Selection of enzyme in processing of soybean cheese and its optimal condition were studied; Lactic acid bacteria and molds starter fitting for processing soybean cheese were selected; Investigate ripeness characteristics of soybean cheese.The research results are as follows:1. The sensory quality of soymilk made different treatments for taking off the beany flavor was judged synthetically with the method of the fuzzy mathematics. The result showed that the effect of removal beany flavor from good to bad the order was hot water soaking with microwave oven heating for five minute to handle soymilk→0.1% NaHCO3 liquor with microwave inactivation enzyme→microwave inactivation enzyme→hot water soaking→brine soaking→lye soaking method. Microwave heating method and hot water soaking method were used to remove beany flavor.2. Soymilk coagulation was studied by experimentation of five proteases.According to clotting time,firmness and cohesiveness of gel, bromelin was selected to use as enzyme in processing of soybean cheese. By four factors and four levels of orthogonal experiments, it was concluded that the additive amount of bromelin was 0.01%, CaCl2 was 0.01%, the time of heat preservation was at 60℃for 30 minutes.3. After comparing fermenting characteristics of five lactic acid bacteria, we can see KLDS 1.0201with the best ability producing of acidity and cohesiveness, Str with better proteolysis and KLDS1.0205 fermenting soymilk with strong producing ability of acetic acid. The results elicited from observing coagulation properties of five lactic acid bacteria showed that the clotting time of Str and Lb was shortest but with relax structure and plenty of whey, KLDS 1.0205with white whey and its structure was more relax than Str's or Lb's, and KLDS 1.0201's and KLDS 4.0303's clotting milk were soft and flexible. From the statistical analysis results of fermenting characteristics of five lactic acid bacteria by synthetic method, we elected KLDS 4.030 and KLDS 1.0201 as the optimal lactic acid bacteria according to its'clotting condition and whey's turbidity results.4. The growth and ability of producing acid of selected lactic acid bacteria were researched in the paper. The results showed that the growth and acid production amount of mixed culture with KLDS 4.0303 and KLDS 1.0201 at the same time were higher than that of culture alone. There was a good intergrowth between KLDS 4.0303 and KLDS 1.0201, which can be used together as starter of soybean cheese.5. The ability of fermenting soymilk, resisting low temperature and resisting salt of six individual molds were researched. And the results showed that the strongest molds of fermenting soymilk and proteolysis was Aspergillus oryzae; the strongest molds of lipolysis ability was Rhizopus oryzae ,and the second was Aspergillus oryzae; Aspergillus oryzae and Penicillium oxalicum were able to grow in culture medium with 15 percent of salt at 4℃. Comprehensively, we can use Aspergillus oryzae as molds starter to process soybean cheese.6. Three factors and three levels of orthogonal experiments were used to find the additive amount of molds, the additive amount and ratio of lactic acid bacteria. the result showed that Aspergillus oryzae was 5 %, the ratio of KLDS 4.0303 and KLDS 1.0201 was 1:1,additive amount was 4%.7. Proteolysis and lipolysis, texture and sensory properties of soybean cheese after different ripeness conditions were researched. The result showed that temperature and time had influence to the proteolysis and lipolysis. The amount of soluble nitrogen and free fatty acid in soybean cheese with the ripeness degree at 10℃was higher than of 4℃. However, temperature had a little effect to texture of soybean cheese. With the time continuing, hardness, Springiness and chewiness fell at first, and then increased. From the statistical results of texture analysis and sensory evaluation of soybean cheese with different ripening conditions, we concluded that the ripening condition for soybean cheese was ripening under 10℃for 28 days.
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