Comparative characterization of key odorants of French fries and oils at the break-in, optimum, and degrading frying stages. (30th January 2022) - Xu, Lirong
Highlights: Three stages of flavor development in French fries (FFs): break-in, optimum, and degrading. Key aroma compounds of FFs and SO were clarified by molecular sensory science. Oxidation at TPC above 22.70% in frying oil induced rancid off-flavor. Abstract: Flavor is a significant factor determining the popularity of French fries (FFs). The frying process of soybean oil (SO) showed three obvious stages—break-in, optimum, and degrading. Further, in order to distinguish the key aroma compounds in each stage, the FFs prepared in SO with total polar compounds (TPC) of 6.5% (FF7), 16.37% (FF16), and 26.5% (FF27), and their corresponding oils (SO7, SO16, SO27) were chosen for sensory-directed analysis. In the break-in stage (6.50–13.50% of TPC), the flavor of the FFs was light and undesirable due to the lower content of ( E, E )-2, 4-decadienal. Then at the optimum stage (15.43–22.70% of TPC), the FFs obtained a higher sensory score, mainly owing to the increase of ( E, E )-2, 4-decadienal with a strong, deep-fried odor. However, in the degrading stage (over 22.70% of TPC), high level of four acids (hexanoic, heptanoic, octanoic, and nonanoic acid), benzeneacetaldehyde and trans -4, 5-epoxy-( E )-2-decenal resulted in flavor deterioration in FF27.