Assessment of seed oil yield and characteristics of ten castor plant (Ricinus communis L.) Accessions in Ogbomoso, Nigeria

Experiment was conducted to assess the seed oil yield and physical and chemical characteristics of ten castor plant accessions. The experiment was laid out in a Randomized Complete Block Design replicated three times. At maturity, the racemes were harvested and seeds were extracted. One hundred gram of seed was taken from each accession for oil extraction. The extracted oils were analysed for physical properties and chemical properties. Data collected were subjected to analysis of variance and means were separated using least significant difference at 5% probability. Significant variations (Pc0.05) occurred among the accession’s oil yield, physical and chemical properties. CASGPMAN produced highest oil content (51.90%) which was significantly higher than values obtained for other accessions. Specific gravity (0.97) obtained from IARCAS001 was significantly higher than others. Viscosity (9.4) and refractive index (1.43) obtained from NCRICAS056 were significantly higher than the values obtained from others. The highest saponification value (184.20 mg KOH/g) obtained from NCRICAS057 was significantly higher than 165.10 mg KOH/g obtained from IARCAS001. The highest free fatty acid (2.6 mg KOH/g) was obtained from NCRICAS057 while the least (1.8 mg KOH/g) was obtained from NCRICAS041. The study therefore concludes that NCRICAS057 produced oil with best physical and chemical properties. Key words: Castor plant, oil yield, moisture content, viscosity, free fatty acid.