糯小麦与普通小麦的固态发酵特性比较

Comparison on Solid State Fermentation Characteristics between Waxy Wheat and Common Wheat

为阐明糯小麦与普通小麦在固态发酵特性方面的差异,分别以糯小麦糯麦12和普通小麦09WB4为原料,进行酒曲固态发酵实验,比较两种小麦发酵过程中的物质动态变化,并以糯麦12为原料,设计正交实验,确定最佳发酵工艺。结果表明,糯小麦的产酒精速率快于普通小麦,糯小麦的酒精含量在发酵3d达到基本稳定,而普通小麦在5d时才达到基本稳定,且糯小麦的最终酒精含量高于普通小麦;两者的还原糖含量都是在发酵3d时达到最低值,之后基本保持稳定;pH值先降低后升高,最后基本稳定在一定范围,总酸的变化趋势与之相反;氨基态氮含量在整个发酵过程中缓慢增加。糯小麦所产原酒在总糖、酒精含量方面优于普通小麦,但酸度高于普通小麦,且氨基酸态氮和挥发酯略低。糯小麦进行酒曲发酵的最佳工艺条件为:发酵温度30℃,用曲量0.8%,发酵时间5d。综合分析,糯小麦的酒曲固态发酵特性与效果优于普通小麦。

Waxy wheat Nuomai 12 and common wheat 09WB4 were fermented by inoculating distiller＇s yeast to clarify the differences on characteristics of solid state fermentation between waxy wheat and common wheat. The dynamic changes of main chemical compositions of waxy wheat and common wheat during solid state fermentation were analyzed and compared, and then the optimal condition of fermentation with Nuomai 12 was also investigated by orthogonal experiment. The results showed that waxy wheat produced alcohol quicker than common wheat, the alcohol content produced by waxy wheat reached maximum and stayed stable at the 3rd day, but that by common wheat reached maximum and stayed stable at the 5th day. The alcohol content produced by waxy wheat was higher than by common wheat when fermentation finished; the reducing sugar content of both of them reached minimum and stayed stable at the 3rd day; pH decreased and then increased, and then stayed stable at almost the same time, while the change of total acid was just opposite; the amino acid nitrogen content increased slightly during fermentation. Total sugar and alcohol content of wine fermented with waxy wheat were higher than those fermented with common wheat, but total acid content was higher and amino acid and volatile ester content were lower. The result of orthogonal experiment showed that the optimal condition of fermentation with waxy wheat by inoculating distiller＇s yeast was as follows： fermentation temperature at 30℃, amount of starter at 0.8%, fermentation time for 5 d. In conclusion, the effect and characteristic of solid state fermentation with waxy wheat by inoculating distiller＇s yeast were better than those with common wheat.