Gas-Liquid Chromatographic Analysis of Blackberry Wine Extracts Fermented by Different Yeast Strains

¹ Department of Food Science and Technology, Oregon State University, Corvallis, Oregon, 97331.

Four strains of yeast with different fermentation properties were used in the study to ferment blackberries. The wine that resulted was extracted with ethyl chloride, concentrated by distillation and analyzed by gas chromatography.

Gas chromatography was found to be an effective method for detecting the fermentation products of yeasts and consequently for differentiating between yeast strains. However, greater instrument sensitivity or a larger amount of the wine would be desirable to detect the compounds present in trace quantities.

A tentative identification, using the enrichment technique, was made of several peaks. These, in order, were believed to be: 2, ethyl acetate; 3, ethanol; 4, propanol; 5, isobutanol; 6, butanol; 7, isoamyl alcohol and act-amyl alcohol; 9, methyl octanoate; 10, 2,3-butylene glycol or ethyl octanoate; 13, linaloöl; and 14, ethyl decanoate.

At their high concentrations, the compounds tentatively identified (peaks number 2, 4, 5 and 7) may be expected to contribute to the flavor and aroma of blackberry wine. Certainly, other minor constituents contribute too, and it is possible that certain of these minor constituents, besides being responsible for the organoleptic differences in wines fermented by different yeast strains, are clues to the enzymatic behavior of yeasts.