EFFECTS OF DEGUMMING AND BLEACHING ON PHYSICOCHEMIAL PROPERTIES OF CRUDE SUNFLOWER OIL

The oil sample used for this study was obtained from sunflower seeds. The oil was extracted by solvent extraction; the crude oil obtained was degummed and bleached. The oil samples were assessed for their physicochemical parameters and fatty acid composition. The specific gravity of all samples was 0.92, while the refractive index range values were 1.47-1.48. The colour ranges between 7-18 units, flash, fire, smoke and turbidity points were in the range value of 335-339, 339-342, 233-235 0C and 5-8jtu respectively. The free fatty acid ranged between 0.51-1.40(% linoleic acid), acid value 1.02-3.09(% linoleic acid), saponification value 188.64-197.43 mg KOH/g oil, peroxide value 12.60-20.40 Meq.peroxide/kg, and iodine value 131.60-145.87 wjs. The yield was 41.30%. The fatty acid composition was determined using gas chromatography. The fatty acids detected in the oil samples were Myristic, palmitic, palmtoleic, stearic, oleic, linoleic, linoleric and arachidic acids. Linoleic acid dominates with range values of 51.65-67.66 %/100g. The result indicated among others, the oil contains high degree of unsaturation, and the quality characteristics of the oil improve upon treatment with phosphoric acid and bleaching earth.