Effect of hot-air drying temperature on volatile organic compounds in corn using headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS)

This study investigated the effects of hot-air drying (HD) temperature (50-90°C) on volatile organic compounds in corn. The results demonstrate that HD temperature significantly altered both the composition and concentration of volatile organic compounds in corn. A total of 658 volatile organic compounds were identified using headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS). As the HD temperature increased, the contents of ketones, esters, and alcohols decreased, whereas those of aldehydes and heterocyclic compounds increased. Multivariate statistical analysis indicated that the flavor profiles of HD70 and HD80 corn were similar. Based on ROAV analysis, 22 key flavor compounds were identified. Compared with fresh corn, HD promoted the formation of heterocyclic compounds such as 2-ethyl-3,5-dimethylpyrazine, which enhanced the roasted and nutty flavors of dried corn. These findings provide a foundation for further research on the metabolic pathways of volatile organic compounds in corn. They also offer a theoretical basis for optimizing drying processes to improve flavor quality. • Detection of volatile organic compounds in corn using HS-SPME-GC-MS. • HD significantly increased the content of heterocyclic compounds. • ROVA screening identified 22 key flavor compounds. • HD promoted a shift in corn flavor from a fresh, sweet aroma to a roasted taste. • Temperature exerts a significant regulatory effect on flavor.