The function of refining equipment is to remove impurities from cooking oil
The function of refining equipment is to remove impurities in cooking oil, maintain the biological characteristics of oil, and retain or extract useful substances. In fact, the refining facility does not remove all impurities, but selectively removes them. Other components of oils and fats other than the oil triester are called impurities.
According to the composition and properties of impurities in gross oil, it can be divided into three categories:
(1) insoluble solid impurities, such as sediment, meal powder, fiber, clay, catalyst and so on.
(2) colloidal impurities, such as free fatty acids, sterols, vitamin E, pigments, vitamins, gossypol, etc.
(3) volatile impurities, such as water, alcohols, hydrocarbon solvents, odorous substances, etc.
Most impurities are bad for the quality and storage of oil. For example, water not only affects the transparency of oil but also promotes the hydrolysis and rancidity of oil. Free fatty acids affect flavor and promote deterioration. Phospholipid can make grease cloudy, and when heating will produce black precipitate, foaming, bitter, etc. Various pigments directly affect oil color, but also promote oil rancidity; The presence of colloid, sulfur-containing, phosphorous compounds, soap feet, heavy metal salts, etc., makes it difficult to remove acid in subsequent processes such as stripping.
