Preliminary Microbiological Studies on the Preservation of Palm Wine

Palm wine is essentially a heavy suspension of yeasts and bacteria in fermenting palm sap. The water extract of a local preservative, from the bark of Sacoglottis gabonensis , failed to inhibit several yeasts and bacteria from palm wine. Sodium metabisulphite, diethylpyrocarbonate (DEPC) and sorbic acid inhibited to varying extents micro-organisms in palm wine. Sorbic acid was thought to be the most suitable preservative tested since DEPC left a residual pungent smell and sodium metabisulphite was not suitable because it is unacceptable to man above 0.35 mg/kg of body weight (Mossel, 1971). Pasteurization at 70° for 30 min was more effective than any of the chemical methods in reducing the microbial load of the wine. It is suggested that pasteurization at 70° for 30 min combined with subsequent treatment with sorbic acid may prove useful as a means of preserving palm wine.