The process of flour manufacturing and potato variety
affected the anthocyanins content. The anthocyanin content of
the flour from purple-flesh potatoes of the Blue Congo and Valfi
varieties decreased compared to raw material, from 72.2% to
68.8%; and in particular, the dominant anthocyanin, petunidin-
2-p-coumaroylrutinoside-glucoside, was lost. Nonetheless, the
total anthocyanin content and the basic pigment, petunidin-3-caffeylrutinoside-
5-glucoside, did not change significantly in the
product from Salad Blue potatoes (also purple-fleshed) but other
anthocyanins present in the flour from this variety showed slight
variations.