Soya Bean
Glycine max

Family: Fabaceae or Leguminosae

What it is like

Glycine max is a ANNUAL growing to 0.6 m (2ft). See above for USDA hardiness. It is hardy to UK zone 8. It is in flower from July to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. It can fix Nitrogen. Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It cannot grow in the shade. It prefers moist soil.

Height (m): 0.6

Where it is found

Lowland thickets, C. and S. Japan.

E. Asia.

Conservation Status:

Countries/locations it is found in

How it is used

Food

Rating: 4

Mature seed - cooked. The seeds furnish one of the world's most important sources of oil and protein, they can be eaten as they are in soups, stews etc, though they are also very commonly used in the preparation of various meat substitutes. The dried seed can be ground into a flour and added to cereal flours or used for making noodles etc. The Japanese make a powder from the roasted and ground seed, it is called 'Kinako' and has a nutty flavour and fragrance - it is used in many popular confections. The sprouted seed is eaten raw or added to cooked dishes. The toasted seeds can be eaten as a peanut-like snack. The seed is also made into numerous fermented foods such as miso and tempeh and is also used to make soya milk, a valuable protein supplement in infant feeding which also provides curds and cheese. The seed contains 20% oil and 30 - 45% protein. All seeds on a soybean plant mature at essentially the same time. Maturity of the seed is accompanied by a rapid dropping of the leaves and drying of the stems. Average yield of beans is about 1700 kg/ha. High-yielding cvs, adapted to the locality and grown under proper culture and favourable conditions will yield more than twice the average yield. The immature seed is cooked and used like peas or eaten raw in salads. The strongly roasted and ground seeds are used as a coffee substitute. The young seedpods are cooked and used like French beans. An edible semi-drying oil is obtained from the seed. It is cooked or can be used as a dressing in salads etc and for manufacture of margarine and shortening. Young leaves - raw or cooked.

Oil: Oil

Seed: includes nuts, cereals, peas and beans.

Seedpod: things such as Okra, French and Runner beans.

Coffee: the various substitutes that can be used instead of coffee.

Milk: made from plants, that is.

Medicine

Rating: 2

The fermented seed is weakly diaphoretic and stomachic. It is used in the treatment of colds, fevers and headaches, insomnia, irritability and a stuffy sensation in the chest. The bruised leaves are applied to snakebite. The flowers are used in the treatment of blindness and opacity of the cornea. The ashes of the stems are applied to granular haemorrhoids or fungus growths on the anus. The immature seedpods are chewed to a pulp and applied to corneal and smallpox ulcers. The seed is antidote. It is considered to be specific for the healthy functioning of bowels, heart, kidney, liver and stomach. The seed sprouts are constructive, laxative and resolvent. They show an oestrogen-like activity in the body and are also antispasmodic.The sprous are used in the treatment of oedema, dysuria, chest fullness, decreased perspiration, the initial stages of flu and arthralgia. A decoction of the bark or root is astringent. Soybean diets are valued for treating acidosis. Since soybean oil has a high proportion of unsaturated fatty acid, it is recommended, like safflower, poppy seed, etc. to combat hypercholesteremia. Commercial grades of natural lecithin, which are often derived from soybean, are reported to contain a potent vasopressor. Medicinally lecithin is indicated as a lipotropic agent. Soybean is listed as a major starting material for stigmasterol, once known as an antistiffness factor. Sitosterol, also a soy by-product, has been used to replace diosgenin in some antihypertensive drugs.

Antidote: Counters poisoning.

Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.

Diaphoretic: Induces perspiration.

Laxative: Stimulates bowel movements in a fairly gentle manner.

Ophthalmic: Treats eye complaints.

Resolvent: Breaks down tumors. This might be placed under antitumor.

Stomachic: Aids and improves the action of the stomach.

Other

Rating: 4

The seed contains up to 20% of an edible semi-drying oil. It is non-drying according to another report. This oil has a very wide range of applications and is commonly used in the chemical industry. The oil is used industrially in the manufacture of paints, linoleum, oilcloth, printing inks, soap, insecticides, and disinfectants. Lecithin phospholipids, obtained as a by-product of the oil industry, are used as a wetting and stabilizing agent in food, cosmetic, pharmaceutical, leather, paint, plastic, soap, and detergent industries. Both the meal and the soy bean protein are used in the manufacture of synthetic fibre, adhesives, textile sizing, waterproofing, fire-fighting foam and many other uses. The plant is sometimes grown as a green manure. The straw can be used to make paper, stiffer than that made from wheat straw. The plant is an excellent source of biomass. The oil from the seeds can be used as a diesel fuel whilst the stems can be burnt as a fuel.

Biomass: Provides a large quantity of plant material that can be converted into fuel etc.

Green manure: Fast-growing plants that can be used to increase the fertility of the soil.

Oil: Vegetable oils have many uses, as lubricants, lighting, soap and paint making, waterproofing etc. This does not include the edible oils unless they are also mentioned as having other uses.

Paper: Related to the entry for Fibre, these plants have been specifically mentioned for paper making.

Nitrogen Fixer: Plants that fix nitrogen in the soil

How it is grown

A fairly easily-grown plant, it grows best in a sunny position on fertile, well-drained soils, but does tolerate a wide range of soil conditions. Soybeans will brow better than many crops on soils that are low in fertility, droughty or poorly drained. Prefers a well-drained sandy soil. Prefers a slightly acid soil. Soya does not grow well in a wet climate, nor will it withstand excessive heat or severe cold winters. The plant has been reported to tolerate an annual precipitation in the range of 31 to 410cm (though it requires at least 50cm for a good crop), an annual mean temperature range of 5.9 to 27°C and a pH in the range of 4.3 to 8.4 (preferring 6 - 6.5). Soya is one of the most widely cultivated plants in the world, being grown for its oil and protein rich edible seed, there are many named varieties. A subtropical plant, but its cultivation extends from the tropics to as far north as latitude 52°N. The species, and most of its cultivars, is a short-day plant and does not flower or set seed unless the daylight hours are less than 13 hours per day. There are three basic types of soya bean, those with green seeds are considered to be the most tender and best flavoured and are the type best suited for northern climates. Black seeded forms are normally used dried and yellow seeded forms are used for making soya milk, flour etc. The plant requires a hot summer with a mean July temperature between 16 and 18°c and a dry autumn if it is to do well in Britain, though it is as hardy as the runner bean, Phaseolus coccineus. The best crops outdoors in Britain are obtained if the plants are started off in a greenhouse and planted out in late spring although a direct sowing outdoors in early May can succeed in good summers but yields will then normally be low. Many cultivars will not flower in the shorter days of late summer in the northern hemisphere and so are not suitable for growing in Britain. Some botanists separate the cultivated forms of soya from this species and call them G. soja. Sieb.&Zucc. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. Soybean soils must contain the proper nitrogen-fixing bacteria. When grown on the same land for 2 - 3 successive years, increasing yields are obtained year after year. Seed can be purchased that has been treated with this rhizobium, it is unnecessary on soils with a pH below 5.5 but can be helpful on other soils. When removing plant remains at the end of the growing season, it is best to only remove the aerial parts of the plant, leaving the roots in the ground to decay and release their nitrogen. Research at the University of Illinois has crossed Glycine max (annual soybean) with Glycine tomentella (perennial) which could lead to the production of a perennial edible soybean.

Propagating it: Pre-soak the seed for 12 hours in warm water and then sow in early spring in a greenhouse. The seed should germinate within two weeks at a temperature between 12 - 16°c. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in late spring or early summer, after the last expected frosts. Seed can also be pre-soaked for 12 hours in warm water and then sown in situ in late spring, though this will not yield well unless the summer is very hot.

Best place to grow: Cultivated Beds;

Habit: Annual

Hardiness: 7-10

Growth:

Soil: Light (sandy), medium

Shade: No shade

Moisture: Moist

Things to keep in mind

The raw mature seed is toxic and must be thoroughly cooked before being eaten. The sprouted raw seed is sometimes eaten and is considered to be a wholesome food.

Its other names

Local names

Synonyms

G. hispida. G. soja. Sieb.&Zucc.