Differences in the Formation of Certain Acetamides in Grape and Apple Wines

Abstract

N-ethyl and N-isoamyl acetamides were detected in a Zinfandel wine, but not in wines fermented from apple must. When appropriate amines were added to apple must, the acetamides of these compounds were readily detectable in the wine produced. However, efforts to induce the formation of these acetamides in model solutions were unsuccessful. The model solutions consisted of the appropriate amine in aqueous solutions of either acetyl CoA, acetyl phosphate, or yeast culture. The presence of N-ethyl, N-isobutyl, and N-isoamyl acetamides in wine extracts was confirmed by combined gas chromatography-mass spectrometry. While the presence of acetamides appears to distinguish grape wine from apple wine, the biochemistry of the formation of these fermentation products remains unverified.