Wheat classification according to its origin by an implemented volatile organic compounds analysis

Abstract

Food volatile organic compounds (VOCs) analysis is a useful tool in authentication and classification processes, but, to date, the analysis of wheat VOCs is still little explored. In this study a method of analysis based on solid phase microextraction coupled with gas chromatography-mass spectrometry was optimized by testing different types of fibers, sample preparation methods and amounts, extraction temperatures and times, desorption times and oven programs. The analysis was applied to six wheat cultivars harvested in different areas, and permitted to identify 158 VOCs, of which 98 never found before. A principal component analysis performed on the dataset showed that the area of cultivation accounted for the highest source of variability. Partial least squares analysis permitted to correctly classify wheats based on their cultivation area and species, and to identify the most discriminant VOCs. These results are promising for the study of the influence of geographical origin on wheat quality.

Keywords: GC–MS; Pedoclimatic conditions; SPME; Volatile organic compounds; Wheat species.