Effect of Cottonseed Oil Refining Stages on Fatty Acid Composition and Oil Quality

In this study, it is investigated the effects of 8 different cottonseed oil refining stages (decanter input, decanter output, after neutralization, after the first washing, after the second washing, dryer output, bleaching output, deodorization output) on quality and fatty acid composition. Color value, refractive index, free fatty acidity, soap amount, peroxide value, conjugated diene-triene amount, α-tocopherol amount and fatty acid composition of cottonseed oils obtained from the refining stages were determined. A continuous decrease in color values was observed. The value of refractive index, free fatty acids , peroxide value varied between 1.4625-1.4645 (Nd-40⁰C), 0.03-2.28% and, 0-7.8 meq O2/kg, respectively; the amounts of soap, conjugated diene, conjugated triene, α-tocopherol were between 0-871.63 ppm, 4.13-14.12, 1.68-6.42 and, 51.99-76.88 µg/g, respectively. Concerning fatty acid composition, the amount of oleic, linoleic, palmitic acid were determined between 17.0-17.4%, 53.9- 54.4% and, 23.68-23.76%, respectively. While the refining stages have a significant impact on the quality of cottonseed oil; they did not cause a significant change on the fatty acid composition.