Winterization of oil is a process of removing the higher melting point parts from oil like waxes or triglycerides by slowly cooling vegetable oils and felling saturated glycerides from the solvent. Used primarily for oils in salad dressings. Mainly applied in bioindustry. The most common oil that is winterized is Rice Bran oil which has a high content of waxes, fatty acids and lipids.
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Winterization of oil Wikipedia(Text) CC BY-SA