Identification of the Volatile Components of Buckwheat Flour and their Distributions of Milling Fractions

Studies on the Flavor of Buckwheat Part 1

Abstract

The volatile concentrates of a stone-milled buckwheat flour were prepared by a continuous distilation-extraction appratus and the components were isolated and identified by gas chromatography and mass spectrometer. Following 45 compounds were found; 13 alcohols, 6 aldehydes, 6 methyl ketones, 2 esters, 6 aromatic hydrocarbons, 7 alkanes and 5 other compounds. On the other hand, seven flour fractions were obtained by roller-milling and their volatile components were investigated. First three fractions consisted of mainly endosperm, and second three had high contents of testa and embryo. The last one was mainly pericarp. The best evaluation score for flavor was obtained for fraction 4 and the second for fraction 5. The major 13 peaks of the volatiles were further investigated. Gradual increase was observed in the amount of n-alkyl alcohols and salicylaldehyde from fraction 1 to 6, and this was extreme for fraction 7. But two peaks containning either n-hexanal or n-nonanal, 2-octanol and n-tetradecane were higher for fraction 3 and 4. These distributions may be related to the evaluation of flavor.