毛霉40899和毛霉M/T混合发酵腐乳的研究

Study on Sufu fermented by Mucor 40899 and Mucor M/T

从腐乳毛坯中分离得到毛霉M/T,以毛霉40899和毛霉M/T为混合发酵剂,采用单因素法和响应面法研究混合菌种发酵腐乳的前发酵工艺,并在最优前发酵条件下考察混合菌种发酵过程中腐乳的氨基酸态氮、质构特性和色度的变化,得出如下结果:经鉴定,毛霉M/T为放射毛霉属;腐乳前发酵最优条件为发酵时间60 h,毛霉40899与毛霉M/T质量比1∶1,乳酸pH值3. 5.在此条件下,腐乳的蛋白酶活力达到最大值48. 015 U/m L.腐乳后发酵至30 d时,腐乳中氨基酸态氮含量为0. 53 g/(100 g),达到腐乳行业标准中的成熟标准.腐乳成熟时的硬度、黏附性、弹性等质构特性良好,色差值与市售成熟腐乳接近.

Mucor M/T was isolated from sufu pehtze.Using Mucor 40899 and Mucor M/T as mixed starters,the pre-fermentation process of Sufu was studied through single factors and response surface optimization method.Then,the changes of amino acid nitrogen,texture and chromaticity of Sufu fermented by mixed strains were studied under the optimal pre-fermentation conditions.The results showed that Mucor M/T was identified as the Actinomucor.The optimal pre-fermentation conditions were as follows:fermentation time was 60 h,strain quality ratio of Mucor 40899 and Mucor M/T was 1:1,pH value was 3.5.Under the optimal conditions,the protease activity reached 48.015 U/mL.After post-fermentation of 30 d,the content of amino acid nitrogen in Sufu was 0.53 g/(100 g),which met the mature standard in the industry standard of Sufu.The texture,adhesion and elasticity of Sufu were good.The color difference value was close to that of commercially mature fermented Sufu.