Enzymatic Extraction of Oil fromBalanites Aegyptiaca(Desert Date) Kernel and Comparison with Solvent Extracted Oil

Abstract

Aqueous enzymatic extraction of oil from Balanites aegyptiaca (desert date) kernel was optimized using a mixture of four enzymes (alcalase, cellulase, viscozyme L and protease). The physicochemical properties and fatty acid composition of the oil obtained by enzyme assisted aqueous extraction and byorganic solvent extraction were compared. Using 2% of each enzyme and 1:10 of water-to-kernel flour ratio, the yield of oil extraction was 38%, estimated in comparison with extraction by Soxhlet method. Linoleic acid was the most prominent fatty acid, followed by oleic acid, and palmitic acid. No significant differences (P > 0.05) were observed in the fatty acid composition of the oil extracted using enzymes mixtures and organic solvents. However, the oil obtained by aqueous enzymatic extraction presented a significantly lower (P < 0.05) acid value, peroxide value, color intensity and phospholipids content than the oil obtained by solvent extraction. Practical Application The enzymatic process described for oil extraction from desert date kernel is environment-friendly as it does not require organic solvents and does not produce harmful waste, which is desirable not only for the safety of employees, but also for environmental protection. Oil with superior characteristics than those obtained by organic solvent extraction is produced, due to its lower FFAs and peroxide values and lower color intensity. Additionally, the overall costs of the refining process are reduced because the phospholipids are retained in the residual solid phase and there is no need of degumming.