摘要：The effect of moisture content variation on the characteristics and oil yield of tiger nut (Cyperus esculentus) seeds was investigated. The oil was extracted using the Soxhlet method at 9.5%, 20%, 30% and 40% moisture content for sample A, B, C and D respectively. The extracted oil was characterized using standard methods. The result showed a percentage oil yield of 25.89%, 19.05%, 12.48% and 12.14% for sample A, B, C and D respectively. The viscosity (mm2/s), specific gravity and smoke point ranges from 0.53-2.27, 0.91-0.84, and 231-215 respectively. The saponification value (mg/KOH/g), iodine value (g/100g) and acid value (mg/KOH/g) are 143.06, 185.13, 260.87, 294.52; 72.00, 88.45, 85.60, 88.45 and 3.37, 30.86, 65.90, 71.81 for sample A, B, C and D respectively. The peroxide value (m/mol/kg) and free fatty acid (mg/KOH/g) ranges from 2-21 and 6.73-143.62 respectively for the extracted oil at moisture content range of 9.5- 40%. Moisture content has no effect on the refractive index of tiger nut oil; the high free fatty acid value indicates its edibility. It can be concluded that oil yield decreases with increase in moisture content, with the highest oil yield obtained at 9.5% moisture content. Therefore, an initial seed moisture content of 9.5% is recommended for the extraction of oil to obtain maximum oil yield. The oil can be use as lubricant, cooking as substitute for other vegetable oil and good for soap making.
