Deodorization function during edible/vegetable oil refining

Deodorization meaning: All kinds of vegetable oils have their own unique flavor and taste. After deacidification and decolorization, there are traces of aldehydes, ketones, hydrocarbons, low molecular weight fatty acids, glyceride oxides and white clay. The process of removing these bad odors is called deodorization.

The deodorization method includes a vacuum stripping method, a gas blowing method, a hydrogenation method, and etc. The most common method is vacuum stripping, which uses high vacuum, high temperature combined with direct steam stripping to remove the gas components in the oil.

Deodorization mechanism is based on the same conditions, the vapor pressure of the odor small molecule component is much larger than the vapor pressure of the triglyceride, that is, the odor substance is more volatile. Therefore, the principle of steam distillation is used for stripping and deodorization. The principle of steam distillation deodorization is that when water vapor passes through the grease containing the odor component, the vapor-liquid surface contacts, the water vapor is saturated by the volatile odor component, and escapes at a partial pressure ratio, thereby the purpose of removing the odor component is achieved.

Physical vacuum deodorization is mainly the physical refining method for stripping free fatty acids (FFA). Deodorization of oil and fat not only removes the odorous substances in the oil, improves the smoke point of the oil, improves the flavor of the edible oil, but also improves the stability, color and quality of the oil. Because it can remove free fatty acids, peroxides and their decomposition products and some thermosensitive pigments while deodorizing, remove the volatile decomposition products of proteins in the mold oil, remove small molecular weight polycyclic aromatic hydrocarbons and residual pesticides to the safe range.