Soybean oil

Vegetable soybean, is an herbaceous plant from the Fabaceae family (legume) naturally originated in southeastern Asia (Japan, Korea, and China) that was domesticated 3.000 years ago because of its young pods and edible seeds. Their early introduction to the U.S. can be traced back to the mid-eighteenth century, with the largest official introduction occurring in the early 1900s.

Soybeans have high amount of protein and oil, and they are used into diverse food products. Modern soy oil is a stable high quality triglyceride ingredient used widely in commercial processed foods.

It is the major edible oil in use in the United States and is a labeled ingredient of premium food products.

Soy oil is used in cooking, such as margarine, shortening, salad oil as well as in industrial products (paints, printing inks, disinfectants, biofuel, and linoleum).

Soybean oil is a complex mixture of five fatty acids (palmitic, stearic, oleic, linoleic, and linolenic acids) that have vastly differing melting points, oxidative stabilities, and chemical functionalities.

The concentration of soybean oil ranges from 83 g/kg to 279 g/kg. Soybean oil contains a high amount of unsaturated acids important in the human nutrition: α-linolenic acid (omega-3 acid), linoleic, γ-linolenic and arachidonic acid (omega-6 acid), and oleic acid known as omega-9.

The proportion of linoleic acid of soybean oil ranged from 49% to 53.5% and the palmitic acid of oils varied between 9.2% and 11.2%. The major sources of tocopherols were γ-tocopherol, α-tocopherol, and δ-tocopherol in all varieties of soybean oil.

Modern soybean processing starts with solvent extraction to obtain crude oil and defatted meal. For hexane extraction, the solubility of oil and hexane is the basic principal, and it can have over 99% of oil recovery rate.

The oil in water emulsion is formed after the extraction process due to the insolubility of water and oil, and the demulsification is applied to recover the oil from the emulsion.

Crude oil contains variable amounts of non-triglyceride materials. To remove some of these impurities from the crude soy oil and convert it to a high-quality edible oil, it is necessary to subject crude oil to a series of refining operations, including degumming to remove lecithin, neutralization to separate out free fatty acids and bleaching to remove pigments and the residues of previous refining steps. Oil refining is usually a continuous process.

Deodorization is the last process step used to improve the taste, odor, color, and stability of the oil by removal of undesirable substances. All commercial deodorization, whether in continuous, semi-continuous, or batch units. is essentially a steam-stripping of the oil for removal of free fatty acids and other volatile materials.

The final product is a refined, bleached, and deodorized oil, commonly known as RBD oil.
Soybean oil