Vegetable oil is from grain and plants through pressing and extraction process. The crude oil alway have little phosphatide, FFA, pigment, mechanical impurities, moisture, solvent, waxiness, etc. So it must be refined from degumming,, deacidfication, dehydration, desolventizing, decolorization, deodorization, dewaxing and winterization process then can reach different standards of edible oil.