The influence of thermal process of coloured potatoes on the content of glycoalkaloids in the potato products

► Coloured potatoes contained lower than 300 mg kg−1 d.w. of glycoalkaloids. ► The highest changes of proportion between α-solanine and α-chaconine were in crisps. ► Peeling process, cooking of un-peeled potato and cooking peeled potato decreased TGA content. ► The highest decrease of TGA were found in crisps and French fries.