Effects of Potato Processing and Frying on Oxylipin Concentrations

Abstract

Potatoes undergo several processing steps including blanching and par-frying to form frozen French fries, which are typically fried in oil subjected to multiple frying cycles. The present study aimed to comprehensively measure the effects of potato processing (i.e., blanching, par-frying, deep frying and repeated frying cycles) on the concentration of primary oxidized fatty acids known as oxylipins in potatoes and the oil used to fry them. Compared to raw peeled potatoes, blanching decreased linoleic acid (LA)-derived epoxides and diols and increased α-linolenic acid-derived hydroxides. Par-frying and one cycle of deep frying reduced several hydroxylated and ketone metabolites of LA or ALA, and increased LA-derived diols relative to raw potatoes. Repeated frying cycles increased several LA- and ALA-derived oxylipins in oil. Some but not all of these changes were reflected in potato French fries heated in the same oil. It is concluded that distinct oxylipin profiles are observed when oil and potatoes are subjected to different processing conditions.