Soya oil is obtained from soya beans (seeds from Leguminose Glycine max. L.) by pressing or extraction, after which it is usually refined.
The soya bean is a native of China, where it was mentioned as far back as 2800 B.C., under the rule of the Emperor Chennung. The bean also became established in Japan at an early stage. Here, it was not the oil, but Tofu, a substance similar to quark, which was of importance. With its high fat and protein content, the soya bean has been a favourite food in Eastern Asia since ancient times. Missionaries brought the plant to Europe in 1740, but it was not until the end of the 19th century that the soya bean reached America. There, it ran into difficulties initially (the bacterial strain Rhizobium japoninicum, which is specific to Asian soil, was missing; as a 'short-day plant', the soya bean would not ripen in temperate latitudes) but it then caught on rapidly, with extensive cultivation.
The pea-like fruit is yellow, green or black in colour. Nowadays, soya beans are cultivated not only in America (principal world cultivation centre) but also in Canada, Brazil, Eastern Asia and the former Soviet Union. Ideally, the soil needs to be loamy and sandy, with a sufficiently high proportion of nitrogen bacteria, day-lengths of 12-16 hours and temperatures of 30-32° C, with warm nights.
The seed oil content is approx. 18%, this oil being collected after the seed has been dried, cleansed, peeled, pulverised and heat treated, by pressing it to yield an oil rich in palmitic, oleic, linoleic and linoleneic acids. However, it is usually obtained by means of (solvent) extraction. The clear, pale yellow, semi-drying liquid with a faint, characteristic smell is a typical all-round-oil, 55-65% of which consists of multiple unsaturated fatty acids.
Soya oil is used primarily as an edible oil and in the production of margarine and confectionery. In the pharmaceuticals trade, soya oil is used as a source of energy for intravenous nutrition. In the dietetics and babyfoods businesses and in the food industry, the oil is used for salad dressings and mayonnaise. In specialist industries, the oil is used for soap production and as a stand oil for paints, oil colours, linoleum, printing colours and alkyd resins.
INCI Name: Glycine Soja Oil