Components of Topnote Aroma of Soy Sauce

Topnote aroma concentrate from soy sauce was prepared by the use of closed system apparatus including a circular pump and cold traps. The aroma concentrate and its isopentane extract were analysed by combined gas chromatography and mass spectrometry. A large amount of ethanol, ethyl acetate, an adequate amount of acetaldehyde, isobutyraldehyde, isovaleraldehyde, 1, 1-diethoxy-2-methylpropane, 1, 1-diethoxy-3-methylbutane, isoamyl-alcohol and a trace amount of dimethylsulfide were found to be the constituents of topnote aroma of good quality soy sauce.