The tea shoots of cultivars Zijuan, Zhongcha 108 and Wuniuzao, with high, middle and low resistances to the tea green leafhopper were collected and cultured in water. Every tea shoot was introduced by 3 leafhoppers with 2 day old, and the shoots suffered for 0, 12, 24, 36, 48 and 60 h respectively. After being damaged, the tea shoots were plucked to produce the steamed tea samples. The taste, aroma and color of tea soup of the steamed tea samples were detected by electronic tongue, electronic nose and colorimeter respectively. The leafhopper-damaged duration was significantly and positively correlated with sourness value (SRS) and saltiness value (STS) of tea soups of three cultivars. The leafhopper-damaged duration on cultivar Zijuan was positively correlated with sourness value (BRS), and significantly negatively correlated with both umami value (UMS) and sweetness value (SWS). The leafhopper-damaged duration on cultivar Zhongcha 108 was positively correlated with BRS, and significantly positively correlated with both UMS and SWS. The leafhopper-damaged duration on cultivar Wuniuzao was significantly and negatively correlated with BRS, UMS and SWS respectively. Data acquired by electronic tongue was analyzed by the principal component analysis (PCA) and the soft independent modeling of class analogy (SIMCA). In both PCA and SIMCA coordinate systems, the six leafhopper-damaged tea samples distributed linearly for each cultivar. Data by electronic nose was also analyzed by PCA and SIMCA, then by PCA or SIMCA coordinate system, the 6 leafhopper-damaged tea samples also distributed linearly for cultivars Zijuan and Zhongcha108, but not Wuniuzao. The colorimeter results revealed that during the time course of damage from 0 h to 60 h, the chroma of yellow-green of tea soups of cultivars Zijuan and Wuniuzao deepened, and the brightness of tea soup of cultivar Zhongcha 108 obviously fell. It was considered that electronic tougue and electronic nose may effectively discriminate resistant cultivar from susceptible cultivar, and differentiate damage degree in tea samples.%剪取对于叶蝉分别具高抗、中抗和感性的紫鹃、中茶108和乌牛早茶树新梢,进行水培.每梢分别接种2日龄叶蝉成虫3头,分别为害0、12、24、36、48、60 h之后采叶制蒸青样.以电子舌测其茶汤滋味,电子鼻测其香气,测色计测其汤色.每个品种蝉害历时与茶汤酸度值SRS和咸度值STS显著正相关;紫鹃蝉害历时与苦度值(BRS)正相关,与鲜度值(UMS)和甜度值(SWS)皆显著负相关;中茶108蝉害历时与BRS正相关,与UMS和SWS皆显著正相关;乌牛早蝉害历时与BRS、UMS和SWS皆显著负相关.电子舌数据分别经主成分分析(PCA)和软独立建模分类法(SIMCA)分析绘制坐标图,在图上每个品种的6个蝉害蒸青茶样的位点呈线性排列.电子鼻数据的PCA和SIMCA分析结果分别显示紫鹃和中茶108的6个蝉害茶样在坐标图上呈线状分布,而乌牛早6个蝉害茶样在坐标图上无规则分布.测色计显示,从受害开始至受害60 h,紫鹃、乌牛早茶汤的黄绿色色度加深,中茶108茶汤的亮度则明显下降.最终认为电子舌和电子鼻等感官智能仪器能够有效区分抗、感性品种的蝉害茶样,辨别蝉害程度不一的茶样.
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