Acrylamide formation in red-, purple- and yellow-fleshed potatoes by frying and baking

Potatoes are a significant source of essential macronutrients and many other health-promoting phytochemicals. However, under thermal processing, undesirable harmful acrylamide might be formed. In the present study, the content of acrylamide (LC-ESI-MS/MS) after baking and frying in thirteen colored potato varieties was investigated. Asparagine (LC-ESI-MS/MS), glucose, fructose, sucrose (HPLC-RI) and chlorogenic acid isomers (HPLC-DAD) were determined in raw tubers. Yellow-fleshed potato varieties produced lower acrylamide content (190 mu g/kg FW after frying and 25.2 mu g/kg FW after baking) than red-(1120 mu g/kg FW and 112 mu g/kg FW) and purple-fleshed (2005 mu g/kg FW and 59.1 mu g/kg FW). Acrylamide content positively correlated with fructose (R = 0.265 frying and R = 0.225 baking at p < 0.05), glucose (R = 0.262 frying), and sucrose contents (R = 0.316 frying) that were more limiting in acrylamide formation than higher asparagine levels. Chlorogenic acid isomers also showed a positive effect on the formation of acrylamide content, which was higher in baking (R = 0.356 at p < 0.05). However, under the same temperature, frying caused significantly higher acrylamide production compared to baking (16.5x on average). Climatic conditions at two growing localities had a significant effect on the amount of acrylamide formed in the heat-treated tubers, as higher temperature and lower precipitation caused lower acrylamide content.