Abstract:In order to determine the core quality index of Cabernet Sauvignon wine grape in Hexi Corridor, we established a comprehensive evaluation model for Cabernet Sauvignon wine grape quality. Six samples of Cabernet Sauvignon wine grapes were collected from three representative orchards of Zhangye, Wuwei and Jiayuguan, and the quality of Cabernet Sauvignon wine grapes was determined. The core quality index of Cabernet Sauvignon wine grape was determined by principal component analysis and cluster analysis. The analytic hierarchy process was used to determine the index weight and establish a comprehensive evaluation model of Cabernet Sauvignon wine grape quality. The results showed that: (1) there were significant differences in quality indexes of Cabernet Sauvignon wine grapes from different producing areas. The contents of fructose, sucrose, oxalic acid and citric acid of the Cabernet Sauvignon grape in Guofeng Wine manor of Zhangye City were higher than those in other areas. The contents of soluble solids, soluble sugar, total phenol and malic acid were kept at a high level in each producing area. (2) Correlation analysis showed that there was a very significant positive correlation between glucose content and soluble solids content, fructose content and soluble sugar content in grape fruit. Solid ratio and sugaracid ratio were significantly negatively correlated with titratable acid content. (3) Combined with principal component analysis, cluster analysis and correlation analysis, we found Vc, tannin, fructose and solidacid ratio were determined as the core quality indexes of Cabernet Sauvignon grape. The comprehensive evaluation model for grape quality of Cabernet Sauvignon was established by analytic hierarchy process (Y=0.0960 Vc content + 0.1611 tannin content + 0.2771 fructose content + 0.4568 solidacid ratio (all index contents were standardized). It is found that Zhangye is the best Cabernet Sauvignon grape producing area for fruit quality in Hexi Corridor. Fruit Vc, tannin, fructose and solidacid ratio are the core quality indexes of the Cabernet Sauvignon grape. The established evaluation model can be used to comprehensively evaluate the quality of the Cabernet Sauvignon grape.