Abstract: The purpose of this study was to investigate the effects of different varieties and maturities of peach on the yield and quality of peach juice and to select the optimal variety for juice processing. A total of 45 peach juices from 15 mid-early ripening cultivars harvested at 3 maturities (I, II and III) were measured for 15 quality indicators including sugar, acid, total phenols and browning degree and comprehensive evaluation of their quality was investigated by conventional descriptive statistics, principal component analysis (PCA) and cluster analysis (CA). The results showed that quality indicators varied significantly among different peach cultivars and maturities. A total of 5 principal components were extracted through PCA, which represented 80.333% of the total variability. The first and second principal components (PC1 and PC2) were related to total sugar and acid concentrations. The third and fourth principal components (PC3 and PC4) were related to juice yield and color. The fifth principal component was related to total phenolic concentration and browning degree. In the PC1 versus PC2 score plot, the cultivars with higher comprehensive scores were clearly separated from those with lower comprehensive scores. In the PC1 versus PC3 score plot, the three maturities were clearly discriminated. CA classified the 45 samples into 6 groups on the basis of the measured parameters and the results were consistent with the PCA. The white-fleshed nectarine cultivar ‘Zhongyoutao 12’ harvested at maturity III ranked first in terms of comprehensive score among all these samples, while the white-fleshed peach cultivar ‘Zhongtao 1’ harvested at maturity I ranked last. Overall, peach juice from the yellow-fleshed cultivars had better quality, and the mid-ripening varieties had better quality than the early-ripening varieties. The quality of peach juice was better at higher maturity levels.

Key words: cultivar, maturity, principal component analysis, cluster analysis, juice quality