Omari, Athumani; Mgani, Quintino A.; Mubofu, Egid B.
Description:
This paper reports on the assessment of the quality and quantity of castor oil from castor seeds collected from different regions in Tanzania. The castor seeds from Arusha, Dar es Salaam, Dodo-ma, Iringa, Kagera and Morogoro regions in Tanzania were extracted by Soxhlet method using n-hexane and the oil yields were determined. The yields were 52.78%, 49.95%, 47.89%, 44.23%, 43.71% and 43.69% for Dodoma, Arusha, Iringa, Morogoro, Kagera and Dar es Salaam respectively. The physico-chemical parameters that were determined were refractive index (1.468-1.473), pH 5.7-6.3, viscosity (0.943-0.954), specific gravity (165.50-187.46 mg KOH/g Oil), saponification value (76.68-80 mg KOH/g Oil), iodine value (76.68-80.12 g I2/100 g Oil), acid value (0.44-1.97 mg NaOH/g Oil), free fatty acid (0.22-0.99) and peroxide value (10.79-13.73). Fatty acid profile of castor oil was analysed using Shimadzu GCMS and ricinoleic acid ranged from 83.5% to 92.3% of the total fatty acids in the castor oils