酱香型大曲的理化指标、水解酶系、微生物产酶的关系研究

Relationships among Physiochemical Indices and Hydrolyzing Enzyme Systems and Enzymes-produced-ability in Jiangxiang Daqu

摘要:

酱香型大曲是典型的高温大曲，本文主要对酱香型大曲的理化指标以及水解酶系的种类和酶活力进行测定。研究发现，酱香型大曲的理化指标符合地方标准DB 52/T 871的规定；酱香型大曲中水解酶系主要为蛋白酶、淀粉酶和果胶酶。结合酱香大曲的水解酶系实验结果和原料小麦的成分，对已从酱香型大曲分离鉴定的19株细菌和17株霉菌进行产酶实验，测定其产酸性蛋白酶、中性蛋白酶、糖化酶、纤维素酶、果胶酶和脂肪酶的能力。研究发现，水解酶系能够部分反映出曲中微生物的种类和数量；甲基营养型芽孢杆菌、黄曲霉和阿姆斯特丹散囊菌对酱香型大曲水解酶系贡献比较突出。将功能微生物制作成酶制剂，可用于提高酱香大曲的品质，为优化制曲工艺和强化大曲的制备提供理论依据。

Abstract:

Jiangxiang Daqu is a typical high-temperature Daqu. The physiochemical indices and the types and activities of the hydrolyzing enzymes present in Jiangxiang Daqu were assessed. The results showed that the physiochemical indices of Jiangxiang Daqu met with the requirements of local standards, DB 52/T 871, and the major enzymes present in it were protease, amylase, and pectinase. The results of the experiments to determine the hydrolyzing enzymes and components of wheat (the raw material) showed that 19 strains of bacteria and 17 strains of mold were isolated from Jiangxiang Daqu. These were used to conduct the enzyme production experiment, and capacities of these microorganisms to produce acid protease, neutral protease, saccharifying enzyme, cellulase, pectinase, and lipase were measured. The results suggested that the hydrolyzing enzymes could partially reflect the structure and quantity of microorganisms in the Daqu; Bacillus methylotrophicus, Aspergillus flavus, and Eurotium amstelodami were the major contributors to the hydrolyzing enzymes in Jiangxiang Daqu. The enzymes prepared by functional microbes could be used to improve the quality of Jiangxiang Daqu. These findings provide a theoretical foundation for the optimization of the Daqu-making technique and the preparation of intensified Daqu.