低盐固态工艺条件下米曲霉3.042和米曲霉RIB40酿造酱油发酵性能的比较

Comparison of Fermentation Performance between A.oryzae 3.042 and A.oryzae RIB40 in Low-salt Solid-state Fermentation of Soy Sauce

探讨了在低盐固态酱油酿造工艺下,我国广泛应用的米曲霉3.042和日本的米曲霉RIB40在发酵性能方面的差异。对比了两株米曲霉种曲孢子数、大曲制备工艺、发酵过程中理化指标、有机酸含量以及酱油风味物质方面的不同。研究发现米曲霉3.042具有产孢快、生长迅速的特点。通过跟踪测定蛋白酶活、纤维素酶活和糖化酶活,确定了两株米曲霉的最佳收曲时间均为36h。同时发现米曲霉RIB40的糖化酶活很高(3208.939U/g干基,36h)。理化指标的变化情况表明:采用两株米曲霉制曲酿造酱油均达到了特级酱油标准。在有机酸方面,米曲霉RIB40酱醅的乳酸和乙酸的含量具有一定优势,这有利于酱油良好口感的形成。风味物质的检测结果表明:米曲霉RIB40酿造酱油中醇类物质具有优势,而米曲霉3.042在酯类物质方面具有优势。在实际生产中,可以根据产品需要选择合适的菌株。

The fermentation performance differences of A.oryzae 3.042 widely used in China and A.oryzae RIB40 from Japan are studied by using low-salt solid-state fermentation method.The koji spores number,koji preparation process,physical and chemical indicators in fermentation process, organic acids content and soy sauce flavor substances of two strains of A.oryzae are compared.It is found that the spores of A.oryzae 3.042 grow fast,and they are much more than those of A.oryzae RIB40.Protease activity,cellulose activity and glucoamylase activity are measured during the growth of koji and the best time to end the growth of koji of two strains of A.oryzae are identified as 36 h. The glucoamylase activity of A.oryzae RIB40 is quite high （3208.939 U/g dry basis,36 h）.The changes of data of physical and chemical indicators during the fermentation indicate that using the two strains of A.oryzae,premium soy sauce has been made,which reaches the super standard.The con-tent of lactic acid and acetic acid of the fermented grains of A.oryzae RIB40 has certain advantages, which is conducive to the formation of good taste.The results of flavor substances show that the soy sauce of A.oryzae RIB40 has high content of alcohols,while the A.oryzae 3.042 has an advantage in esters.In actual production,according to the product needs,the appropriate strains can be selected.