Homogenity of oil and sugar components of flour amaranth investigated by GC-MS

Abstract

Gas chromatography with mass spectrometry (GC-MS) was used for performing a qualitative analysis of liposoluble and hydrosoluble flour extracts of three genotypes of Amaranthus sp. All three samples were first defatted with hexane. Hexane extracts were used for the analysis of fatty acids of lipid components. TMSH (Trimethylsulfonium hydroxide, 0.2M in methanol) was used as the transesterification reagent. With transesterification reaction, fatty acids were esterified from acilglycerol to methyl-esters. Defatted flour samples 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 methyl-esters of fatty acids are very similar in all the three samples. Such a similarity was not detected in the analysis of soluble sugars. The following test cluster analysis was used for the comparison of liposoluble and hydrosoluble flour extracts of three genotypes of Amaranthus sp.