仿草包曲在黄酒发酵中的应用及其对黄酒风味的影响

为了提高生麦曲的发酵效率及品质,以传统草包曲的制作工艺为基础,将生小麦经现代通风控温控湿工艺培养后制成仿草包曲,分别比较仿草包曲与对照块曲的酶活性能和微生物群落结构、仿草包曲与对照块曲所酿黄酒理化指标、风味物质含量.结果表明:仿草包曲的酶活性能高于对照块曲;仿草包曲的细菌群落结构与对照块曲基本相似,但不同属真菌的相对丰度存在差异;仿草包曲与对照块曲在黄酒发酵过程中的理化指标变化趋势相同,仿草包曲所酿黄酒的酒精度较对照块曲提高4.7％,氨基氮降低9.6％,总酸与还原糖变化趋势相同;风味物质中醇类与酯类物质较对照块曲分别增加51.06 mg/L与18.27 mg/L,醛类与酸类物质含量差异不显著.主成分分析结果表明:仿草包曲具有与对照块曲相近的发酵性能,熟麦曲的添加是仿草包曲与对照块曲发酵黄酒的风味组成差异显著的主要原因.

Application of Imitated Caobao Koji in Huangjiu Fermentation and Its Influence on Huangjiu Flavor

In order to improve the efficiency and quality of raw wheat koji fermentation, basing on the traditional production technology of Caobao koji, the raw wheat was cultured and made into imitated Caobao koji with modern temperature and humidity control technology. The enzyme activity and community structure of the two kinds of koji, the physicochemical index and flavor substance content of Huangjiu brewed by the two kinds of koji were compared. Results showed that the enzyme activity of imitated Caobao koji was higher than that of control block koji. And the bacterial community structure was comparable with that in the control block koji, while the relative abundance of fungi in different genera was different.The physical and chemical indexes of Huangjiu fermented by imitated Caobao koji or control block koji had the same changing trend.The alcohol content and amino nitrogen of the Huangjiu brewed with imitated Caobao koji were increased by 4.7% and decreased by 9.6% than those of the control block koji, respectively. And the changing trends about the content of total acid and reducing sugar in both groups was same. The alcohol and ester flavor substances were increased 51.06mg/L and 18.27mg/L than those in the control block koji, respectively.There was no significant difference between aldehydes and acids.Principal component analysis showed that the fermentation performance of imitated Caobao koji was similar to that of control block koji,and the main reason for the significant difference in flavor composition between imitated Caobao koji and control was the addition of cooked wheat koji.