Chemical Composition of Some Natural Palm Wine Preservatives

Palm wine is the commonest name of the beverage obtained from fermented palm sap, the exudate from tapped unopened spathe of oil palm tree (Elaeis guineensis). This refreshing wine of West and Central Africa is very sweet but within 24 hours the concentration of sucrose falls to less than 50% the initial amounts due to a rapid sugar fermentation by microorganisms. In Cameroon, Central Africa, traditional attempts to preserve palm wine imply the introduction of natural preservatives mostly barks and leaves from edible or medicinal plants. The leaves of Cymbopogon citratus, Pimenta racemosa, Vernonia amygdalina, Ocimum basilicum and the barks and the leaves of Garcinia lucida and of Adansonia digitata commonly used in palm wine preservation were analyzed for their chemical composition. The results showed that lipid, protein, ash, crude fiber, total sugars and vitamin C contents were respectively from 15.70 ± 1.13 to 23.57 ± 1.80%, from 8.38 ± 0.38 to 43.81 ± 3.69%, from 1.14 ± 0.17 to 10.06 ± 0.39%, from 11.74 ± 1.11 to 48.42 ± 0.55%, and from 1.49 ± 0.02 to 22.56 ± 0.59% and from 55.76 ± 3.15 to 175.71 ± 2.09 μg /100 g dw. The phyto-chemicals levels were respectively from 1.37 ± 0.22 to 3.61 ± 0.6 % for total alkaloids, 2.66 ± 0.12 to 4.80 ± 0.24 % for total phenolics and 0.57 ± 0.09 to 1.88 ± 0.09 mg /100 g dw for total saponins. Concerning anti-nutrients, the oxalates levels were higher than the threshold value (250 mg/100 g) reported as safety limit. Despise the proven antimicrobial benefits of alkaloids, saponins and phenolics found in those leaves and barks, caution shall be paid during their use due to their high oxalates levels.