Abstract: In order to explore the changes of volatile components in half-boiled and pan-fried potatoes at different processing stages, the volatile components and metabolites were determined by gas chromatography-mass spectrometry (GC-MS), gas chromatography-ion mobility spectrometry (GC-IMS) and widely targeted metabolomics. It was found that the color of potatoes changed from light yellow to golden yellow to brown yellow after being half-boiled and pan-fried. GC-MS analysis showed that the volatile components in raw potatoes mainly included alcohols, with a relative content of 91.85%, and the key flavor substances were octanal, nonanal, decanal, and 2-pentylfuran. The major volatile components in half-boiled potatoes were aldehydes and esters, with relative contents of 38.82% and 15.81%, respectively, and the key flavor substances were octanal, nonanal, decanal and 2-pentylfuran. The major volatile components in half-boiled and pan-fried potatoes were aldehydes and pyrazines, with relative contents of 57.40% and 28.76%, respectively, and the key flavor compounds were octanal, nonal, decal, 2-pentylfuran, trans-2,4-heptandienal, 2-ethyl-5 or 6-methylpyrazine, and 2-ethyl-3,6-dimethylpyrazine. A total of 36 volatile components were identified by GC-IMS, and the types of these volatile components were different from those identified by GC-MS, but the results of GC-MS and those of GC-IMS complemented to each other. By widely targeted metabolomic analysis, 22 kinds of metabolites, such as amino acids and their derivatives, carbohydrates, nucleotides and their derivatives, lipids and their derivatives, and flavonoids were identidied, among which 14 were identified as different metabolites with variable importance in the projection (VIP) > 1 at P < 0.05 in t-test, which were significantly correlated with volatile components. L-Asparagine, L-glutamic acid, acetamide, and phosphoric acid had a significant correlation with various volatile metabolites, and their contents were higher in the samples.

Key words: half-boiled and pan-fried potato; processing; flavor substances; chroma; metabolic compounds