Differences in anthocyanin content and antioxidant activity of potato tubers with different flesh colour

The aim of this study was to determine that the total anthocyanin content (TAC) and antioxidant activity (AOA) in potato flesh with different colours grown in the Czech Republic. Four yellow- or white-, six purple- and four red-fleshed varieties were grown in 2009 at two different sites (Valecov – highland, seed potato area at 460 m a.s.l., Přerov nad Labem – lowland, new potatoes area at 178 m a.s.l.) in precise field trials. For purple- and red-fleshed varieties, average TAC values ranged from 61.5 to 573.5 cyanidin mg/kg of FM and significant effect of the variety of the TAC was found. High content reached the Violette and Vitelotte varieties with dark purple flesh, and the low est content the Blue Congo variety with light purple marbled flesh. Significantly higher TAC was found in a lowland area Přerov nad Labem, which is probably related to drought stress. The lowest AOA was achieved by a group of varieties with yellow or white flesh – averaging 82.8 mg ascorbic acid equivalent/kg FM, in a group of red-fleshed varieties it was higher 4.34 times and in a group of purple-fleshed varieties even 5.03 times higher. Also between purple-and red-fleshed varieties significant differences in AOA were found, both high and low values of AOA showed the same varieties as in the case of the TAC. Among experimental sites higher AOA was also demonstrated at Přerov nad Labem. Correlation analysis showed a strong correlation between AOA and TAC (r = 0.8099).