Abstract: This study aimed to explore the characteristics of main nutrient contents in citrus pulp from different verities and to develop a comprehensive evaluation method for citrus fruit quality. A comparative analysis of the contents of 20 phenolic substances in fruit pulp and eight conventional fruit quality indicators was carried out among 11 varieties. Factor analysis was applied to comprehensive quality evaluation. The results showed that hesperidin as the major flavonoid and ferulic acid as the chief phenolic acid were detected in the pulp of all these varieties. Five cultivars of sweet orange (Citrus sinensis L. Osbeck) were richer in vitamin C and sinapic acid than six mandarin cultivars (C. reticulata Blanco). The total contents of phenolic compounds in pulp of the mandarin cultivars Gold Nugget and Shasta Gold were the highest among the 11 citrus varieties. The comprehensive quality of sweet oranges was generally better than that of mandarins. The comprehensive quality of the five new mandarin cultivars was better than that of the major cultivar W · Murcott, and the comprehensive quality of the four new sweet orange cultivars were poorer than that of the major cultivar Newhall. Overall, our results demonstrated that the contents of flavonoids and phenolic acids in pulp were important indicators of fruit quality. The comprehensive evaluation of citrus fruit quality by factor analysis could provide a basis for selecting citrus varieties with high quality.

Key words: citrus, phenolics, fruit quality, comprehensive evaluation