MISCELLA REFINING TEST METHOD FOR THE DETERMINATION OF COTTONSEED OILCOLOR

Most of the cottonseed oil mills in the United States have already con verted to expander solvent extraction and miscella refining. This prac tice permits mills to produce and market a consistently light-colored, prime bleachable summer yellow cottonseed oil at reduced cost and ref ining loss. A laboratory-scale miscella refining test was developed to assess the oil quality in terms of its color. The test involves the a ddition of 3 parts oleic acid per 100 parts of crude oil in the miscel la followed by refining with 2.5 parts NaOH when crude oil contains le ss than 4.5% free fatty acid (FFA). When crude oil contains FFA betwee n 4.5 and 7.5%, no oleic acid is added prior to refining with 2.5 part s NaOH. When crude oil contains FFA higher than 7.5%, no oleic acid is added and the caustic addition table in American Oil Chemists' Societ y Method Ca 9a-52 is followed. The test was conducted at room temperat ure and gave reproducible colors comparable to commercially refined oi ls.