Crude vegetable oil and fats obtained after rendering, crushing or solvent extraction contain variable amounts of unwanted components such as free fatty acids (FFA), mono and di-glycerides, phosphatides (gums), sterols, tocopherols, hydrocarbons, pigments, vitamins, glucosides, glycolipids, protein fragments, traces of pesticides and trace metals. Oil refining process removes these unwanted constituents without damaging glycerides and with minimum loss of desired constituents, which in turn improves flavor, odor, color and stability.