| With the high improvement of living standard, people improve their requirements to the taste, nutrition and exterior of food. The character of food influences the economic efficiency of enterprise directly. As a traditional fermented food of China,fermented bean curd have the particularly exquisite character. It is soft and smooth, highly nutritious, rich in not only free fatty acid, amino acid, oryzanin, riboflavin, calcium and phosphorus, but also some physiological active substance in soya bean as well as some physiological active substance created through fermentation. According to microorganism fungus used in sufu fermentation, the hairy mould model sufu is researched relatively deep so far. But the research of head mold model sufu is quite little, especially the Rhizopus oligosporus Saito model sufu. This paper is exactly researching the Rhizopus oligosporus Saito GIM3.381model sufu, providing some theory basis for the development of traditional sufu industry. Implemented some aspects in research as follows:Firstly, the protease activity as index, observe the influence of fermantative temperature, time, pH and inoculating amount on protease activity, use the single factor and the orthogonal test optimize conditions of sufu primary fermentation;secondly, measure and analyse the change of protease activity, water, sodium chloride, texture and chroma in the whole fermenting process; Thirdly, evaluate the contents of amino acid nitrogen and sense organ parameter of the mature sufu. Achievements in research as follows:(1) Fermenting sufu by Rhizopus oligosporus Saito GIM3.381, the optimum of primary fermentation:temperature20℃, time48h, pH2.5, inoculating amount10%. In this process, the protease activity is22.10μg/mL, besides, when primary fermentation finished, the hypha is pure white and compact, character is good, reaching the standard of sufu production.(2) During the fermentation of sufu, follow-through measure and analyse the texture characteristic of tofu, semifinished product, salting pehtze and salting pehtzesalting pehtze ansufu in different after-fermentation time, Get a conclusion about theChange of texture and structure: hardness increased first and then decreased, elasticity decreased gradually, adhesion increased gradually, coherence decreased gradually, adhesiveness and chewinesschewiness both tend to increased firstlyand then decreased, the50d in the period of after-fermentation, change tend to stable. Compared with tofu, the hardness of mature billet decreased75.5%, elasticity decreased42.2%, adhesion increased42.5%, coherence decreased54.6%, adhesiveness decreased89.2%, chewiness decreased93.1%. 3. During the fermentation of sufu, water of billet decreased from tofu to the end of salting pehtze stage; But following the after-fermentation, the content of water increased. Sodium chloride increased quickly in salting pehtze stage, decreased gradually in after-fermentation, then tend to Stable state in the50d.4. During the fermentation of sufu, change of brightness, red degree and yellow degree are not obvious in primary fermentation and salting pehtze stage; Since monascorubin insoluble in water while soluble in alcohol and acetic acid, following the after-fermentation, monascorubin dissolved a little in the ingredients which the content of alcohol is limited. As a result, the surface of sufu Will appear color, red degree increased, yellow degree increased slightly, brightness decreased gradually.5. The50d in the period of after-fermentation, texture change of sufu tend to be stable, the smell of alcohol have cleared away, texture is exquisite, speculating sufu have matured. At this moment, the contents of Amino acid nitrogen, Water and Sodium chloride were1.54g/100g,66.1%and8.9g/100g. Accordingly, the50d in the period of after-fermentation reaching the mature standard. |
PDF Full Text Request