Analyses of polyphenols, soluble sugars and organic acids in fruits of 8 varieties of imported table grape

Objective To evaluate the fruit quality of imported table grape varieties intuitively and scientifically, and to provide reference for selecting and breeding excellent table grape varieties in Xinjiang region.

Methods The contents of soluble sugar, organic acid and phenolic substances were determined in 8 varieties of table grape and then evaluated by TOSIS method.

Results The soluble solids content of 8 varieties of table grape ranged from 16.23% to 23.30%, the total soluble sugar content of 'Red Italy' fruit was the highest, the fructose content of 'Cuibao seedless' fruit was the highest, and the sucrose content of 'Xiangfeng' fruit was the highest. The titrable acid content of 8 fruits ranged from 0.24% to 1.01%, the total organic acid content of 'Xiangfeng' fruit was the highest, among which the malic acid and citric acid content were the highest, and the tartaric acid content of 'Centennial seedless' fruit was the highest. The total phenol content of the fruits of 8 varieties was between 1.18mg/gand 3.86mg/g, the total phenol contents of 'Cuibao seedless' and 'Xiangfeng' fruits were higher than those of the other 6 varieties, and the flavonoids, flavanols and tannins contents of 'SP740' fruits were the highest. According to TOPSIS evaluation, the comprehensive scores of 'Xinyu' and 'SP740' ranked the top, and the comprehensive scores of 'SP528' and 'Xiangfeng' ranked the last two.

Conclusion There is no difference in soluble sugar and organic acid components, but there is significant difference in content, and 'Xinyu' and 'SP740' have better effect.