Abstract:

In order to evaluate antioxidant capacity of peach fruit using phenolic compounds content，fruits of 12 red，7 white and 4 yellow flesh peach cultivars were used to analyze the difference of individual and total phenol content. Comparing with white and yellow flesh peach cultivars，most of the red ones had higher epicatechin and total phenol content. Eight phenol content indices were generalized into 4 independent comprehensive indices through principal component analysis after correlation analysis between different indices. Comprehensive evaluation value（D）was calculated based on both subordinate function value and weight. After comprehensive ranking on flesh antioxidant capacity of different cultivars，we found that the red flesh cultivar‘Beijing Yixianhong’had the highest D value，meanwhile，red flesh types sorting in the front and most of white and yellow types followed behind，which was in accordance with the result of cluster analysis. These results suggested that peach fruit antioxidant capacity was closely related with flesh color. Peach fruit antioxidant capacity could be evaluated synthetically using both individual and total phenol content by principal component analysis，subordinate function method and cluster analysis method. The order of the contribution of phenol to the antioxidant capacity of peach fruit was neochlorogenic acid，total phenol，epicatechin，ferulic acid，chlorogenic acid，rutin，catechin and quercetin.

Key words: peach, phenolic compounds, evaluation of antioxidant capacity, principal component analysis, subordinate function analysis, cluster analysis