本文通过添加一株嗜盐产香酵母菌（鲁氏酵母）与米曲霉协同制曲，探讨制曲过程中酶系、各项理化指标及风味与酵母代谢调控的相关性。动态监测制曲过程中酵母菌落数、米曲霉孢子数、酶系活力、理化指标的变化规律及采用GC-MS对成曲进行挥发性成分分析。结果表明，当酵母的添加量为1.5×106个/g曲料，米曲霉接种量为0.15%（m/m）时，米曲霉孢子数无明显变化，中性蛋白酶活与对照组相当，36 h时达到3100 U/g，α-淀粉酶活较对照组降低了22%，糖化酶活与对照组相比增加了7%，氨肽酶活、酸性羧肽酶活与对照组无明显差异。制曲结束时对照组与添加酵母氨基态氮和还原糖含量基本相近，有机酸含量低于对照。添加酵母和对照组成曲中分别检测出32种，23种挥发性风味物质。综合分析知，接种一定量的酵母菌协同制曲并未对米曲霉生长及酶系产生显著影响，但改善了曲料的风味品质。

A halophilic aromatic yeast (Zygosaccharomyces rouxii) was added to Aspergillus oryzae and their synergistic effect on the preparation of koji was explored in terms of the metabolic regulation of yeast with enzymatic systems, physicochemical indices, and volatile compounds. Changes in the numbers of the yeast colonies and Aspergillus oryzae spores, the activity of the enzymatic systems, and physicochemical indicators during the preparation of koji were dynamically monitored, while the volatile components of the finished product were analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that when the amount of yeast added was approximately 1.5 × 106 yeast/g koji and the inoculum size of Aspergillus oryzae was 0.15% (m/m), the number of Aspergillus oryzae spores did not significantly change and the neutral protease activity was 3100 U/g at 36 h, which was comparable to the results obtained for the control group. However, α-amylase activity decreased by 22% and saccharifying enzyme activity increased by 7% in the yeast-inoculated group, while aminopeptidase and acidic carboxypeptidase activities did not exhibit significant difference compared to the results obtained in the control group. After the preparation of koji was complete, the concentrations of amino nitrogen and reducing sugar were almost the same for the yeast-inoculated and control groups, while the organic acid content of the yeast-inoculated sample was lower than that of control. There were 32 and 23 volatile components identified by GC-MS in the yeast-inoculated and control groups, respectively. Comprehensive analysis showed that inoculation of a halophilic aromatic yeast during the preparation of koji did not show a significant effect on the enzymatic system and growth of Aspergillus oryzae; however, it improved the flavor and quality of the finished koji.

湖北省自然科学基金（2013CFA096，2013CFB032）；湖北省教育厅项目（Q20141409）