Optimum conditions for expression of oil from Allanblackia floribunda seeds and assessing the quality and stability of pressed and solvent extracted oil

The study was carried out to establish the optimum conditions for the extraction of oil from Allanblackia floribunda nuts and also assess the quality and stability of both the crude pressed oil (CPO) and solvent extracted oil (SEO). The optimum conditions of extraction were established by varying the moisture levels of the milled seed samples under different temperatures. The oil was expressed using a manual screw press and the soxhlet apparatus was used to extract the oil using petroleum ether as the solvent. Quality parameters assessed included specific gravity, refractive index, free fatty acids, acid value, melting range, unsaponifiable matter, saponification value, iodine value, peroxide value and calorific value. The results showed the seeds were high in oil. The oil yields from manual expeller and solvent extraction were 48.60 and 67.59% respectively. The oils had a melting point ranging between 42 - 44°C. There were no significant differences in the quality parameter such as refractive index, specific gravity, iodine value, saponification value, peroxide value, free fatty acid, acid value and ester value. There were however, significant differences in the moisture and volatile matter as well as unsaponifiable matter of the oils. The peroxide value and free fatty acid content were used as the indicators for stability of the oil. The pressed oil was more stable during storage of the oil in plastic containers than the solvent extracted oil. Allanblackia seeds can be used commercially in the food sector and also for non food purposes.   Key words: Allanblackia floribunda seeds, mechanical extraction, optimum conditions, quality characteristics.