The plant is sometimes called the greater or yellow bean. The fruit is a hairy pod that grows in clusters of 3-5, and each pod usually contains 2-4 edible seeds. Soya beans occur in various sizes, and in many seed coat colours, including black, brown, blue, yellow, green and mottled. The hull of the mature bean is hard and water resistant.
Cultivation: It is native to native to east Asia. Soya beans are an important global crop. The main producers of soya are the United States, Brazil, Argentina, China and India. For successful cultivation the crop requires climates with hot summers (mean temperatures of 20 to 30°C) (68 to 86°F), temperatures of below 20°C and over 40°C and moist, rich alluvial soils. Soya beans contain very high levels of protein and they can dry out, yet survive and revive after water absorption, making them a very valuable crop. Raw soya beans are toxic to humans and many animals. A lot of the crop is processed for animal feed; despite this soya appears in a large variety of processed and pre-packaged foods, processed as oils or fermented to produce soya sauce.
Uses: Raw soya beans are toxic to humans, and must be cooked to make them safe. Soya is a good source of protein for vegetarians, for people who cannot afford meat, or those on low-fat diets. Soya vegetable oil is an important ingredient in many meat and dairy substitutes. Soya also has properties which make it suitable for food production requiring high temperature cooking, such as tofu, soy milk and textured vegetable protein (soya flour). Soya beans are also the basis for soy sauce.
Health Value: Among the legumes, the soya bean has the highest protein and oil content (together they account for about 60% of dry soya beans by weight). The remainder consists mainly of carbohydrate. The beans contain significant amounts of omega-3 fatty acids, phytic acid, alpha-linolenic acid and isoflavones. They are considered a cholesterol-lowering food.
Varieties: Soya beans vary in growth, habit and height.