红曲霉的分离鉴定及其在米酒中的应用

Isolation and Identification of Monascus and Its Application in Rice Wine

为满足米酒的多元化发展需求,该实验以筛选得到的红曲霉进行红曲米酒发酵,并通过单因素与正交试验进行红曲米酒发酵工艺优化并进行挥发性风味物质的测定。试验从红曲米中分离筛选到1株霉菌,依据形态和ITS序列鉴定,确定该菌株为紫色红曲菌(Monascus purpureus),命名为JXY。以此红曲霉制作的小曲、活性干酵母为糖化发酵剂,糯米为原料,经工艺优化发酵后的红曲米酒色泽淡红,澄清透亮,酒香浓郁,富含淡淡的清香,是一款具有红曲独特风格的低酒度新型保健米酒。此红曲米酒的最佳工艺条件为:料液比1:2.0g/mL,发酵时间8d,红曲霉种子液接种量体积分数6‰,pH值6.0,发酵温度28℃。在此最佳条件下,红曲米酒酒精度为13.21%vol,经10名专业人员品评后得到感官评分达最高92分,同时通过挥发性风味物质测定发现酯类物质种类共有8种,醇类物质相对含量达到82.22%。这对红曲霉在米酒酿造中的应用和红曲米酒的品质提升有一定指导作用。

In order to satisfy the diversified development needs of rice wine,in this experiment,the screened Monascus was used for Hongqu rice wine fermentation,and the fermentation process of Hongqu rice wine was optimized by the single factor and orthogonal tests,and volatile flavor substances were determined.One mold strain was isolated and screened from Hongqu rice,and according to morphology and ITS sequence identification,the strain was determined was Monascus purpureus(named JXY).Using the Xiaoqu made by this Monascus,active dry yeast as the saccharification and fermentation agent,glutinous rice as the raw material,the Hongqu rice wine produced via the optimized fermentation process was light red in color,clear and translucent,with rich wine aroma and soft fragrance,thereby being a new type of low-alcohol healthy rice wine with a unique style of Hongqu.The optimal process conditions for this Hongqu rice wine were:material-liquid ratio,1:2.0(g/mL);fermentation time,8 d;inoculation volume fraction of Monascus seed liquid,6‰;pH value,6.0;fermentation temperature,28℃.Under this optimal condition,the alcohol content of Hongqu rice wine was 13.21%vol,and the sensory score reached the highest 92 points during the evaluation by 10 professionals.Meanwhile,a total of 8 types of ester substances and 82.22%relative content of alcohols were found through the determination of volatile flavor substances.This has a certain guiding effect on the application of Monascus in rice wine brewing and the quality improvement of Hongqu rice wine.