EFFECT OF MOISTURE CONTENT ON THE YIELD AND CHARACTERISTICS OF OIL FROM MORINGA OLEIFERA SEEDS

The effect of moisture content variation on the yield and characteristics of oil from Moringa Oleifera seeds were investigated. The oil was extracted using the soxhlet method at 7.28%, 10%, 15% and 20% moisture content for sample A, B, C and D respectively. The extracted oil was characterized using standard methods. The results show a percentage oil yield of 38.01%, 38.48%, 32.56% and 27.53% for samples A, B, C and D respectively. The extracted oil had viscosity (kg/m3) of 43.50, 43.69, 44.00 and 44.30 with specific gravity of 0.90, 0.93, 0.94 and 0.97 for samples A, B, C and D respectively. The results also shows saponification (mg/KOH/mol) and iodine (g/100g) values of 117.12, 93.97, 96.77, 91.16 and 68.58, 68.50, 68.41, 68.42 for sample A, B, C and D respectively. The acid values (mg/KOH/mol) are 3.23, 3.16, 2.81 and 2.81 for sample A, B, C and D respectively. The peroxide value (mg/KOH/mol) and free fatty acid (mg/KOH/mol) ranged between 0.95-1.15 and 5.61-6.45 for the extracted oil at moisture content of 7.28-20%. It can be concluded that oil yield decreases with increase in moisture content, with the highest oil yield obtained at 10% moisture content. Moisture content has no effect on the refractive index of moringa seed oil; the high free fatty acid value indicates its edibility while the iodine value is a measure of the unsaturation of the oil. Therefore, an initial seed moisture content of 10% (w.b) is recommended for the extraction of oil to obtain maximum oil yield while the oil can be use as lubricant, cooking as substitute for other vegetable oil but it is not suitable for soap making.