Analysis of Aroma Components in Four Red Grape Varieties

The aroma components in Cabernet Gernischt,Cabernet Sauvignon,Cabernet Franc and Merlot were identified by gas chromatography-mass spectrometry(GC-MS) and gas chromatography-olfactometry(GC-O).The aroma components in grapes were extracted by vibrating extraction at constant temperature,and the non-volatile components were removed by solvent-assisted flavor evaporation(SAFE).The volatile components were condensed by N2 and analyzed by GC-MS and GC-O methods.A total of 67 aroma compounds were detected and 60 aroma compounds were identified in four kinds of grapes.The major aroma compounds were hexanal,1-hexanol,(Z)-3-hexen-1-ol,acetic acid,(E,Z)-2,6-nonadienal,3-methylbutanoic acid,anethole,hexanoic acid,benzyl alcohol,β-phenylethyl alcohol,β-ionone,2-hexenoic acid,4-methoxy benzaldehyde,and an unknown herb-like compound.Although similar aroma components were observed in four kinds of grapes,the aroma intensities of these aroma components were different.These aroma components were classified into seven categories including fruit aroma,plant flavor,chemical flavor,microbiological flavor,floral flavor,caramel flavor and other flavors according to wine aroma wheel.Among 4 kinds of grapes,the chemical flavor exhibited the highest aroma intensity,which was followed by floral flavor,plant flavor and fruit flavor.The aroma characters of four winemaking grapes were closely correlated with the contents of volatile aroma compounds.