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Tempeh is a traditional Indonesian fermented food mainly made from soybean with zygomyceteous fungi, particularly Rhizopus oligosporus. Fresh tempeh of good quality is a compact and sliceable mass of processed raw material covered, penetrated and held together by dense nonsporulated mycelium of Rhizopus oligosporus. Tempeh has its unique fermentation fragrance, no odor. It can clearly be seen, the quality of tempeh can be extrapolated from the growth of the tempeh fungus. During the fermentation process, the soybeans are gradually covered by white mycelium, and thus the number of visible beans decreases with time, while the color of the tempeh changes. But how to determination of fungal growth in solid state fermentation (SSF), such as the tempeh fermentation process, is extremely difficult. This work developed a fast, accurate, objective and nondestructive method for monitoring soybean tempeh fermentation.In addition, tempeh is a new food for the Chinese people and its unique flover is not yet accepted by our nation. Fresh tempeh and milk as raw material, has developed a new type of Tempeh milk products, formulations and sterilization process.The main research contents and results are as follows:1. Image analysis of tempeh fermentation processAnalysis Tempeh image obtained in the fermentation process to obtain a fermentation process color (including hue, saturation, luminance, luminance standard deviation, yellow and white area ratio) curve. The trend of the mycelial growth can be judged from the color change of tempeh and the end of tempeh fermentation infer22h. And it’s same with the sensory experience.2. Soybean tempeh enzyme inactivation method optimizationFresh tempeh enzyme inactivation treatment, enzyme inactivation temperature, time, pH and other factors material to liquid, the end result is optimized by single factor and orthogonal experiment:Sterilization temperature of100℃, the sterilization time15min, treatment solution pH9. Under this condition for fresh tempeh15.8%lipase residual activity was measured after sterilization, the sensory score was8.2.3. Tempeh-milk formula optimization and stabilizer selectionThe enzyme inactivation Tempeh post processing, developed into a tempeh-milk. The basic formulation process optimized tempeh-milk:after enzyme inactivation,1:4cider, then tempeh juice and milk2:1mixture by adding4%sugar and0.15%xanthan gum.4. Study on tempeh-milk sterilization processTempeh-milk sterilization process choice, the finalized tempeh-milk sterilization process:Fresh tempeh-milk sterilized by Pasteurized sterilize or UHT sterilize after homogenized, sealing preserved.
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