Anthocyanins from Skins and Fleshes of Potato Varieties

Potatoes come in many various colors of tuber peels and/or fleshes. Anthocyanin pigment is responsible for red and purple colors of colored potato varieties. We report anthocyanin determination of a red potato cultivar Kintoki-imo and other colored cultivars grown in Hokkaido, Japan, using DAD-HPLC and ESI-TOF/MS.13C-NMR and 1H-NMR analyses showed that the major Kintoki-imo anthocyanin were pelargonidin 3-(6-O-(4-O-(E)-p-coumaroyl-α-L-rhamnopyranosyl)-β-D-glucopyranoside)-5-β-D-glucopyranoside (pelanin), and pelargonidin 3-(6-O-(4-O-(E)-feruloyl-α-L-rhamnopyranosyl)-β-D-glucopyranoside)-5-β-D-glucopyranoside. The anthocyanin content per 100 g flesh tuber was 2-816 mg. The anthocyanin composition patterns of potato cultivars were classified into five types: type A contained a lot of pelanin and Pg 3-Fr.Rut-5-Glc; type B was similar to type A, except that it included purple pigments such as peonanin and Pn 3-Rut-5-Glc; type C was also close to type A, except that the peonanin content was high; type D had pelanin as the main pigment, but no peonanin; and type E had petanin as the main pigment, but no pelanin.