冠突散囊菌发酵桑叶茶品质研究

Study on the Quality of Mulberry Leaf Tea Fermented by Eurotium Cristatum

为探究冠突散囊菌在制作发酵桑叶茶中的应用,从茯砖茶"金花"中筛选冠突散囊菌,并进行菌落形态特征观察、光学显微镜及电镜观察、18S rDNA测序、同源比对,鉴定得到一株冠突散囊菌,命名为GTSNJ001。利用该菌株,以桑叶为原料,制作冠突散囊菌发酵桑叶茶和桑叶绿茶,以多糖、黄酮、多酚、水浸出率、1-脱氧野尻霉素(DNJ)和感官品评为主要评价指标,研究冠突散囊菌发酵桑叶茶和桑叶绿茶品质。结果表明:与桑叶绿茶相比,冠突散囊菌发酵桑叶茶的多糖、黄酮、多酚含量均下降,降幅分别为76.1%、12%、7.1%,而DNJ和水浸出率含量大幅增加,增加量为未发酵桑叶茶的3倍左右,冠突散囊菌发酵桑叶茶感官品评综合得分也优于桑叶绿茶。

In order to explore the application of Eurotium cristatum from Fuzhuan tea in the production of fermented mulberry leaf tea,we screened and isolated Eurotium cristatum named GTSNJ001 from Fuzhuan tea,through observation of colony morphology,optical microscope and electron microscope,18S rDNA sequencing and homology comparison.Mulberry leaf was used as raw material to produce mulberry leaf tea and mulberry leaf green tea.Polysaccharide,flavonoids,polyphenols,water extraction rate,1-deoxynojirimycin (DNJ) and sensory evaluation were used as the main evaluation indexes to study the quality of mulberry leaf tea and mulberry leaf green tea fermented by Eurotium cristatum.Results show that compared with mulberry leaf green tea,the content of polysaccharides,flavonoids and polyphenols in fermented mulberry leaf tea decreased by 76.1%,12% and 7.1%,respectively,while the content of DNJ and water extraction rate increased significantly,with the increase of about 3 times as much as that of unfermented mulberry leaf tea.The comprehensive sensory evaluation score of fermented mulberry leaf tea was also better than mulberry leaf green tea.