Flavor Characteristic Analysis of Fried Allium tenuissimum L. Flowers by Electronic Nose and Headspace-Gas Chromatography-Ion Mobility Spectrometry

Flavour characteristics of Allium tenuissimum L. (AtL) flowers processed by the Chinese traditional stir-frying method were investigated by electronic nose (E-Nose) and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). E-nose detection with principal component analysis (PCA) revealed that the main volatile components of AtL flowers were nitrogen oxides, terpenes, organic sulfides and sulfur-containing organic compounds, while the stir-frying process distinctly changed the flavor pattern of AtL flowers, resulting in significantly increased levels of sulfur-containing compounds. A total of 56 components were detected across fried AtL (FAtL) and raw AtL flowers, of which 25 were identified as volatile compounds by HS-GC-IMS. The contents of five fat-soluble and two water-soluble compounds in FAtL were far higher than those in AtL, confirming that stir-frying changed the flavor of AtL flowers. In conclusion, the combination of E-Nose and HS-GC-IMS represents an efficient, accurate and sensitive method for the determination of flavor components in Allium plants.