Physicochemical changes of raffia sap (Raphia mambillensis) contents during spontaneous fermentation

Abstract

The chemical content of a substance can influence its shelf life. Fermentation causes changes in freshly tapped sap and therefore makes its large scale use difficult. In order to study the effect of time on fermentation on the raffia sap property, its physico-chemical and microbiological characteristics were determined during five days. The results recorded for the harvest reveal an acidity, proteins and energy of about 67.7°D, 6.69 g/l, and 113.64 kcal/l respectively. Raffia sap acidity and protein content increase during fermentation when the energy value decreases. The microbiological analysis showed that this sap contains an average of 16.46 x 10⁷ cfu/ml of total germs which increases during fermentation. This sap is therefore rich in useful and pathogenic micro-organisms. We noticed that this sap is very rich in lactic acid bacteria and yeasts which could be isolated and exploited for alcoholic and malolactic fermentations in order to obtain a very stable raffia sap.

Keywords: Raffia sap, spontaneous fermentation, physicochemical property, lactic acid bacteria, yeast, nutrient content

African Journal of Biotechnology Vol. 12(41), pp. 6013-6018