Sensory-directed flavor analysis of key odorants compounds development of French fries and oils in the break-in, optimum and degrading frying stage

The flavor is a decisive sensory characteristic that determines the popularity of French fries (FFs). During high-oleic rapeseed oil (RO) frying, the flavor development of FFs showed three noticeable stages including break-in (3.5%-7.5% of total polar compounds (TPC)), optimum (7.5%-22.18% of TPC), and degrading stages (above 22.18% of TPC). Further, in order to distinguish the key aroma compounds in each stage, the FFs prepared in RO at TPC of 3.5% (FF4), 14.5% (FF15), and 26.96% (FF27) and their relevant oils (RO4, RO15, RO27) were selected for sensory-directed analysis. The results revealed that the FF4 had low contents of (E,E)-2,4-decadienal (deep-fried odor) which also caused lower sensory score in FF4 sample. The higher contents of (E,E)-2,4-decadienal in FF15 induced its higher deep-fried odor. The FF27 had higher hexanoic acid (sweaty odor), heptanoic acid, nonanoic acid, benzene acetaldehyde (stale odor), and trans-4,5-epoxy-(E)-2-decenal (metallic odor) compared with FF4 and FF15, thus leading to the undesirable flavor of FF27. Moreover, the decrease of 2,5-dimethylpyrazine and 2-ethyl-6-methyl-pyrazine in FF27 induced the lower roasty flavor, which may also lead to the decline of the sensory score. Similarly, the higher contents of (E)-2-undecenal, hexanoic acid, heptanoic acid, and nonanoic acid in RO27 lead to increase its rancid score and thus lower the sensory score. (c) 2023 Beijing Academy of Food Sciences. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The flavor development of French fries can be divided into three stages: break-in, optimum, and degrading. Different aroma compounds in each stage affect the sensory score of the fries.