Increase in ethanol concentration (20–80 vol.%) in the extraction medium enhanced the amount of anthocyanins that could be extracted from boiled purple-fleshed potatoes only slightly (Fig. 3). However, as concentration of the anthocyanin extract should be carried out after the extraction, higher ethanol concentration in the extract is favorable in this respect as the evaporation of ethanol is easier than that of water due to the higher vapor pressure of ethanol (pethanol(20 ◦C) = 5.8 kPa (The Dortmund Data Bank, 2016); pwater(20 ◦C) = 2.4 kPa (The Dortmund Data Bank, 2016)).