Agriculturae Conspectus Scientificus, Vol 66, No 1 (2001)

Influence of Malolactic Fermentation on the Quality of Riesling Wine


Pages: 59-64


The composition and sensory properties in Riesling wines of suppressed, natural and induced malolactic fermentation (MLF) were investigated. A Riesling wine from the vintage 1998 was produced by the usual technology for white wines. After completion of alcoholic fermentation, wine was racked and divided into 35 L glass bottles for different treatments. The first treatment was suppressed MLF with SO2 and storage at 10°C. The second one included natural MLF and the third MLF was induced with starter culture Oenococcus oeni. After the MLF of the wines was completed, the wines were analysed and sensory tested. The analysis of the organic acids were performed by HPLC and the concentrations of volatile compounds were determined by gas chromatography.
Malic acid decomposition was completed in wines of all MLF treatments and the result was a significant decrease of total acidity up to 1.3 g/L and an increase of the pH value of 0.1 units. No differences in the concentrations of volatile acidity and ethyl acetate were detected between the wines of suppressed, natural and induced MLF.
MLF was not accompanied by tartaric acid degradation. The citric acid concentration was reduced by up to 42 %. The concentrations of 1-propanol, isobutanol, isoamyl alcohol and 2-phenylethanol remained unchanged after malolactic fermentation. The concentrations of isoamyl acetate, isobutyl acetate, ethyl butyrate and ethyl caproate were lower in the MLF wines. These wines contained more ethyl lactate and diethyl succinate. Higher quantities of ethyl caprylate, ethyl caprate, caproic, caprylic and capric acids were determined in the MLF wines.
Wines of suppressed MLF were of inferior quality compared with malolactic fermented wines, while wines of natural MLF were significantly better.


acids; malolactic fermentation; sensory properties; volatile compounds; wine

Full Text: PDF