Soybean oil (
British English
British English (BrE, en-GB, or BE) is, according to Lexico, Oxford Dictionaries, "English language, English as used in Great Britain, as distinct from that used elsewhere". More narrowly, it can refer specifically to the English language in ...
: soyabean oil) is a
vegetable oil
Vegetable oils, or vegetable fats, are oils extracted from seeds or from other parts of fruits. Like animal fats, vegetable fats are ''mixtures'' of triglycerides. Soybean oil, grape seed oil, and cocoa butter are examples of seed oils, or f ...
extracted from the seeds of the
soybean
The soybean, soy bean, or soya bean (''Glycine max'') is a species of legume native to East Asia, widely grown for its edible bean, which has numerous uses.
Traditional unfermented food uses of soybeans include soy milk, from which tofu a ...
(''Glycine max''). It is one of the most widely consumed
cooking oils and the second most consumed vegetable oil. As a
drying oil
A drying oil is an oil that hardens to a tough, solid film after a period of exposure to air, at room temperature. The oil hardens through a chemical reaction in which the components crosslink (and hence, polymerize) by the action of oxygen (no ...
, processed soybean oil is also used as a base for
printing ink
Ink is a gel, sol, or solution that contains at least one colorant, such as a dye or pigment, and is used to color a surface to produce an image, text, or design. Ink is used for drawing or writing with a pen, brush, reed pen, or quill. Thicker ...
s (
soy ink
Soy ink is a plant-based ink derived from soybeans (''Glycine max''). Unlike traditional petroleum-based ink, soy-based ink is environmentally friendly, provides precise colours, and makes it easier to recycle paper. It is slower to dry than many ...
) and
oil paint
Oil paint is a type of slow-drying paint that consists of particles of pigment suspended in a drying oil, commonly linseed oil. The viscosity of the paint may be modified by the addition of a solvent such as turpentine or white spirit, and va ...
s.
History
Chinese records dating prior to 2000 BCE mention use of cultivated soybeans to produce edible soy oil. Ancient Chinese literature reveals that soybeans were extensively cultivated and highly valued as a use for the soybean oil production process before written records were kept.
Production
To produce soybean oil, the soybeans are cracked, adjusted for moisture content, heated to between 60 and 88 °C (140–190 °F), rolled into flakes, and solvent-extracted with
hexane
Hexane () is an organic compound, a straight-chain alkane with six carbon atoms and has the molecular formula C6H14.
It is a colorless liquid, odorless when pure, and with boiling points approximately . It is widely used as a cheap, relatively ...
s. The oil is then refined, blended for different applications, and sometimes
hydrogenated
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic ...
. Soybean oils, both liquid and partially hydrogenated are sold as "vegetable oil", or are ingredients in a wide variety of processed foods. Most of the remaining residue (
soybean meal
Soybean meal is used in food and animal feeds, principally as a protein supplement, but also as a source of metabolizable energy. Typically 1 bushel (i.e. 60 lbs. or 27.2 kg) of soybeans yields 48 lbs. (21.8 kg) of soybean meal. Some ...
) is used as animal feed.
In the 2002–2003 growing season, 30.6 million
ton
Ton is the name of any one of several units of measure. It has a long history and has acquired several meanings and uses.
Mainly it describes units of weight. Confusion can arise because ''ton'' can mean
* the long ton, which is 2,240 pounds
...
s (MT) of soybean oil were produced worldwide, constituting about half of worldwide edible vegetable oil production, and thirty percent of all fats and oils produced, including animal fats and oils derived from tropical plants.
In 2018–2019, world production was at 57.4 MT with the leading producers including
China (16.6 MT),
US (10.9 MT),
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
(8.4 MT),
Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
(8.2 MT), and
EU (3.2 MT).
Composition
Soybean oil contains only trace amounts of fatty carboxylic acids (about 0.3% by mass in the crude oil, 0.03% in the refined oil). Instead it contains esters. In the following content, the expressions "fatty acids" and "acid" below refer to
esters
In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ar ...
rather than
carboxylic acids.
Per 100 g, soybean oil has 16 g of saturated fat, 23 g of monounsaturated fat, and 58 g of polyunsaturated fat. The major
unsaturated fatty acids in soybean oil
triglycerides
A triglyceride (TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids (from ''tri-'' and ''glyceride'').
Triglycerides are the main constituents of body fat in humans and other vertebrates, as we ...
are the polyunsaturates
alpha-linolenic acid
''alpha''-Linolenic acid (ALA), also known as α-Linolenic acid (from Greek ''alpha'' meaning "first" and ''linon'' meaning flax), is an ''n''−3, or omega-3, essential fatty acid. ALA is found in many seeds and oils, including flaxseed, wa ...
(C-18:3), 7-10%, and
linoleic acid
Linoleic acid (LA) is an organic compound with the formula COOH(CH2)7CH=CHCH2CH=CH(CH2)4CH3. Both alkene groups are ''cis''. It is a fatty acid sometimes denoted 18:2 (n-6) or 18:2 ''cis''-9,12. A linoleate is a salt or ester of this acid.
...
(C-18:2), 51%; and the monounsaturate
oleic acid
Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish. In chemical terms, oleic acid is classified as a monounsaturated omeg ...
(C-18:1), 23%.
It also contains the saturated fatty acids
stearic acid (C-18:0), 4%, and
palmitic acid
Palmitic acid (hexadecanoic acid in IUPAC nomenclature) is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.Gunstone, F. D., John L. Harwood, and Albert J. Dijkstra. The L ...
(C-16:0), 10%.
The high-proportion of oxidation-prone polyunsaturated fatty acid is undesirable for some uses, such as cooking oils. Three companies,
Monsanto Company,
DuPont/
Bunge, and Asoyia in 2004 introduced low linolenic
Roundup Ready soybeans.
Hydrogenation
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organ ...
may be used to reduce the unsaturation in linolenic acid. The resulting oil is called hydrogenated soybean oil. If the hydrogenation is only partially complete, the oil may contain small amounts of
trans fat
Trans fat, also called trans-unsaturated fatty acids, or trans fatty acids, is a type of unsaturated fat that naturally occurs in small amounts in meat and milk fat. It became widely produced as an unintentional byproduct in the industrial pr ...
.
Trans-fat is also commonly introduced during conventional oil deodorization, with a 2005 review detecting 0.4 to 2.1% trans content in deodorized oil.
Comparison to other vegetable oils
Applications
Food
Soybean oil is mostly used for
frying and
baking. It is also used as a
condiment
A condiment is a preparation that is added to food, typically after cooking, to impart a specific flavor, to enhance the flavor, or to complement the dish. A table condiment or table sauce is more specifically a condiment that is served separat ...
for
salad
A salad is a dish consisting of mixed, mostly natural ingredients with at least one raw ingredient. They are typically served at room temperature or chilled, though some can be served warm. Condiments and salad dressings, which exist in a va ...
s.
Drying oils
Soybean oil is one of many
drying oil
A drying oil is an oil that hardens to a tough, solid film after a period of exposure to air, at room temperature. The oil hardens through a chemical reaction in which the components crosslink (and hence, polymerize) by the action of oxygen (no ...
s, which means that it will slowly harden (due to free-radical based polymerization) upon exposure to air, forming a flexible, transparent, and waterproof solid. Because of this property, it is used in some printing ink and
oil paint
Oil paint is a type of slow-drying paint that consists of particles of pigment suspended in a drying oil, commonly linseed oil. The viscosity of the paint may be modified by the addition of a solvent such as turpentine or white spirit, and va ...
formulations. However, other oils (such as
linseed oil) may be superior for some drying oil applications.
Medical uses
Soybean oil is indicated for
parenteral nutrition
Parenteral nutrition (PN) is the feeding of nutritional products to a person intravenously, bypassing the usual process of eating and digestion. The products are made by pharmaceutical compounding companies. The person receives a nutritional mi ...
as a source of calories and essential fatty acids.
Fixative for insect repellents
While soybean oil has no direct
insect repellent
An insect repellent (also commonly called "bug spray") is a substance applied to skin, clothing, or other surfaces to discourage insects (and arthropods in general) from landing or climbing on that surface. Insect repellents help prevent and cont ...
activity, it is used as a
fixative to extend the short duration of action of
essential oils such as
geranium oil in several commercial products.
Trading
Soybean oil is traded at the
Chicago Board of Trade in contracts of 60,000 pounds at a time. Prices are listed in cents and thousandths of a cent per pound, with a minimum fluctuation of 5/1000 cents. It has been traded there since 1951.
Below are the
CQG contract specifications for Bean Oil:
References
External links
*
{{Authority control
Soy products
Chinese inventions
Soy-based foods
Vegetable oils