Laboratoire d'Etude et de Recherche en Chimie Appliquée, Ecole Polytechnique d'Abomey-Calavi, Université d'Abomey-Calavi (LERCA/EPAC/UAC), 01 BP 2009 Cotonou, Benin
Palm wine, known as atan in Benin, is a sweet beverage extracted from the oil palm (Elaeis guineens). Highly prized by the population for its high nutritional value, its marketing is very limited due to a lack of or inappropriate means of preservation. In the search for palliatives, the present study aims at the Bio-preservation of palm wine by using orange peels to extend its shelf life. To achieve this objective, the preservative effect of orange peels was evaluated, and the stabilized wine was characterized in physicochemical, nutritional, microbiological and organoleptic terms. Palm wine samples graded A, B and C received 10g, 15g and 20g of orange peel respectively. During the storage period, the bottles that received the peelings in this order burst after one, two, three and four weeks respectively. The flasks that burst early were those with a low peel incorporation rate. The 33cL bottles containing palm wine and 25g orange peel resisted bursting up to 4 weeks of storage. Analysis of physicochemical and nutritional parameters showed that stabilized palm wine was richer in potassium, magnesium, sodium and calcium than the unstabilized control wine. Microbiological analysis of the stabilized palm wine showed that the yeast, Escherichia coli and Staphylococcus loads were lower than in the unstabilized wine. In terms of sensory quality, the study showed that consumers rated the consistency, color and taste of stabilized wines higher than those of unstabilized (control) wines.
In the present study, Phenolic compounds of ethanolic extracts of three organs (leaves, stem barks and roots) of Pterocarpus erinaceus were studied in UV-Visible Spectrophotometer. Furthermore the antiradical activity of these extracts was determined at room temperature by the method based on the reactivity of the extracts with a free radical, stable in solution, the l, l-diphenyl-2-picrylhydrazyl (DPPH). A synthetic antioxidant commonly used in the food and cosmetic industry, quercetin was used as reference to validate the antioxidant potential of phenolic extracts studied. The preliminary assessment of the phytochemical composition of this plant revealed the presence of polyphenols, tannins, free flavonoids, coumarins, terpenes, sterols and anthocyanins. The colorimetric assay revealed that the polyphenols are more concentrated in the bark of Pterocarpus erinaceus rod than in the leaf and root bark of the plant. Similarly, the stem bark of Pterocarpus erinaceus was more active than the leaf and bark of the root, although lower than the standard used (quercetin) activity. The evaluation of the granulometry influence revealed that the extraction solvent diffuses more easily inside the small particles to extract polyphenol molecules.