The Relations between Enzyme System in Jiangxiang Daqu and Enzyme Produced by Microbial Metabolism

Jiangxiang Daqu, produced by wheat, is a block starter containing a variety of fungi and enzymes. With the deep exploration of Jiangxiang Daqu, people know more about Jiangxiang Daqu gradually. The importance of Daqu enzyme system has been highlighted. A large amount of enzyme is produced by microbial metabolism in Daqu. Accordingly, there is surely a direct relation between Daqu enzyme system and microbes in Daqu. In this experiment, the activities of acidic protease, glucoamylase, cellulase, pectinase, lipase in enzyme system in Jiangxiang Daqu were measured. Enzyme production test was carried with 48 bacteria strains and 35 fungus strains which were screened from Jiangxiang Daqu, and the varieties and the activities of the produced enzyme were determined at the same time. The results suggested that, all the screened bacteria strains and fungi strains could produce enzyme, and strains with high-yield of enzyme could be used for the preparation of intensified Daqu. The physiochemical indexes of Jiangxiang Daqu could indirectly reflect the relation between Daqu enzyme system and the microbes in Daqu. This study provided theoretical evidence for the optimization of Daqu- making techniques and the preparation of intensified Daqu.