Authenticity of Lipid and Sugar Profiles of Various Buckwheat Cultivars Investigated by GC-MS System and Multivariate Analysis

Abstract

Gas chromatography with mass spectrometry (GC-MS) was used to perform a qualitative analysis of the liposoluble and hydrosoluble flour extracts of nine buckwheat samples. All samples were first defatted with hexane. Hexane extracts were used for the analysis of the fatty acids of lipid components. Transesterification reagent was TMSH (Trimethylsulfonium hydroxide, 0.2M in methanol). With transesterification reaction, fatty acids esterified from acilglycerol to methyl esters. Samples of defatted flour were dried in the air and then extracted with ethanol. Ethanol extracts were used for the analysis of soluble carbohydrates. TMSI (Trimethylsilylimidazole) was used as a reagent for the derivatization of carbohydrates into trimethylsilylethers. The results show that the dominant fatty acid methyl esters and sugar composition are very similar in all investigated samples. The cluster analysis was used to compare the liposoluble and hydrosoluble flour extracts of nine buckwheat cultivars to establish homogeneity among them and the possibility of their authentication.