冠突散囊菌发酵青钱柳前后特征风味与挥发性物质的变化

Variation of characteristic flavor and volatile substances in Cyclocarya paliurus fermented with Eurotium cristatum

青钱柳(Cyclocarya paliurus)是珍贵的药食两用植物。为改善青钱柳茶风味并提高资源的利用率,采用冠突散囊菌(Eurotium cristatum)对青钱柳茶进行固态发酵,对比检测发酵前后青钱柳茶的感官品质及主要活性物质的含量,并运用基于顶空固相微萃取-气相质谱联用(headspace solid-phase micro extraction/gas chromatography-mass spectrometry,HS-SPME/GC-MS)技术的非靶向代谢组学方法研究挥发性物质的变化。结果表明,发酵后的青钱柳茶滋味甘甜醇和,产生了独特的药香、菌花香;多酚、游离氨基酸、可溶性糖、三萜的含量分别下降53.04%、10.74%、13.46%、27.91%,总黄酮含量上升了25.66%。发酵前后的青钱柳茶中共检测到67种差异挥发性物质(FC≥2或≤0.5,P<0.05,VIP>1),结合香气活度值鉴定出具有辛辣木香属性的月桂烯、丁香酚、α-紫罗兰酮和香叶醇是青钱柳茶的特征香气成分;具有甘草香属性的脱氢紫罗烯是发酵青钱柳茶的特征香气成分。该研究可以为发酵青钱柳茶的风味特性研究提供科学依据。

Cyclocarya paliurus is an edible and medicinal plant.To improve the flavor and the utilization rate of C.paliurus resources,the C.paliurus leaves were fermented with Eurotium cristatum and the differences of sensory quality,main active components and volatile substances between non-fermented and fermented C.paliurus were compared by sensory evaluation combined with nontargeted metabolomics based on headspace solid-phase micro extraction/gas chromatography-mass spectrometry.Results showed that fermented C.paliurus tasted mellow sweet with unique smell.The total contents of polyphenols,free amino acids,soluble sugar and triterpenoids decreased by 53.04%,10.74%,13.46%,and 27.91%,respectively,while flavonoids increasing by 25.66%.Nontargeted metabolomics revealed that 67 volatile substances were significantly regulated(FC≥2 or≤0.5,P<0.05,VIP>1)after fermentation.Based on odor activity value calculation,C.paliurus tea had myrcene,eugenol,α-ionone and geraniol with spicy and woody properties as characteristic aroma components,while fermented C.paliurus tea had dehydro-ar-ionene with licorice property as characteristic aroma component.This study provides a theoretical basis for the research of flavor characteristics of fermented C.paliurus.