Isoamyl Acetate in Scotch Malt Whisky

Abstract

Isoamyl acetate content of Scotch malt whjsky was determined by head space gas chromatographic method.
The highest concentration of isoamyl acetate was observed in Highland malts. Lower concentration was in Islay, Lowland and Campbeltown malts in this order.
But the content of isoamyl acetate was higher in new fillings than in matured malt whiskies. Therefore it was assumed that this ester was principally formed during fermentation of distilling wort, concentrated by distillation into raw whisky and annually disappeared by evaporation during maturation in wood.
Peak of isoamyl acetate on gas chromatogram was sharply appeared by reduced alcoholic concentration. Also it was observed that this ester was rapidly evaporated during testing on 20 v/v% ethanol concentration.