Physical and chemical properties of tigernut oil as influenced by variety and method of extraction

Abstract

This study was carried out to investigate the physical and chemical properties of tigernut oil as influenced by variety and methods of extraction. Oil was extracted from yellow and brown varieties of tigernut using mechanical screw press and N-hexane, and it was characterized for physical and chemical composition. The moisture content, acid value, free fatty acid, iodine value, saponification value and peroxide value for tigernut oil from extraction methods ranged from 2.97 to 3.30%, 0.28 to 0.56mgKOH/g, 0.55 to 1.12g/100g, 66.11 to 69.75gI/100g, 174.93 to 210.06mgKOHg and 0.27 to 0.56MgH2O2, respectively. The range of values for specific gravity, percentage impurity, cloud point, smoke point and melting point are: 0.64 to 0.99g/ml, 0.15 to 0.24%, 9.00 to 25.5°C, 170.5 to 204.5°C and 18.0 to 28.5°C, respectively. However, the study showed that both the physical and chemical composition of tigernut oil were affected by the extraction methods used in this study.