Soya Beans

The soya bean in the UK, or called soybeans in the US, is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses, ranging from animal feed to vegetable oil to soy milk and soy sauce, to tofu and other meat and dairy analogues. The UN Food and Agricultural Organization (FAO) class the plant as an oilseed rather than a pulse.

Soya beans can be broadly classified as “vegetable” (garden) or field (oil) types. Vegetable types cook more easily, have a mild, nutty flavour, better texture, are larger in size, higher in protein, and lower in oil than field types. Tofu and soymilk producers prefer the higher protein cultivars bred from vegetable soya beans originally brought to the United States in the late 1930s. The “garden” cultivars are generally not suitable for mechanical combine harvesting because there is a tendency for the pods to shatter upon reaching maturity.

The main producers of soy are the United States, Argentina, Brazil, China and India. The United States is also the world’s largest consumer of soya beans.

History

Soya beans were a crucial crop in Eastern Asia long before written records. They remain a major crop in China, Japan, and Korea. Prior to fermented products such as soy sauce, tempeh, natto, and miso, soy was considered important for its use in crop rotation as a method of fixing nitrogen in the soil. The plants would be ploughed under to clear the field for food crops.

First introduced into Europe in the early 18th century and to British colonies in North America in 1765, where it was first grown for hay, Benjamin Franklin wrote a letter in 1770 mentioning sending soya beans home from England. Soya beans did not become an important crop outside of Asia until about 1910. In America, soy was considered an industrial product only, and was not used as a food prior to the 1920s.

After World War I, soy became very important for drought-stricken areas of the US during the Great Depression, its nitrogen-fixing properties making it very effective in regenerating soil in parts of the country affected by the Dust Bowl.

Henry Ford also promoted the soya bean, helping develop uses for it both in food and in industrial products, even demonstrating auto body panels made of soy-based plastics. Ford’s interest led to two bushels (120 pounds) of soya beans being used in each Ford car, as well as products like the first commercial soymilk, ice cream and all-vegetable non-dairy whipped topping.

While soya beans first arrived in the Caribbean 1767, it remains a minor crop there, but its uses for human food are growing steadily. Soya beans didn’t arrive in Africa until 1857 with its introduction in Egypt as a food crop. It is now widespread across the continent.

Cultivation

Soya beans are an important global crop, providing oil and protein. Cultivation is successful in climates with hot summers, with optimum growing conditions in mean temperatures of 20 to 30°C (68 to 86°F); temperatures of below 20°C and over 40°C (68°F, 104°F) retard growth significantly. They can grow in a wide range of soils, with optimum growth in moist alluvial soils with a good organic content.

Uses

Approximately 85% of the world’s soya bean crop is processed into soya bean meal and vegetable oil. The bulk of the US soya bean crop is grown for oil production, with the high-protein defatted and “toasted” soy meal used as livestock feed. A smaller percentage of soya beans are used directly for human consumption.

In China, Japan, and Korea, the bean and products made from it are a popular part of the diet. The Chinese invented tofu and also made use of several varieties of soya bean paste as seasonings. Japanese foods made from soya include miso, natto, kinako and edamame. Also many kinds of food are produced using tofu, including atsuage and aburaag. In Korean cuisine, soya bean sprouts, called kongnamul, are used in a variety of dishes, also the base ingredient in doenjang, cheonggukjang and ganjang. In Vietnam, soya beans are used to make soya bean paste, tofu, soya sauce, soya milk and tofu sweet soup.

Health benefits

There are a number of health benefits associated with soya beans including:

  • Reduction of prostate cancer risk in men
  • Decreased risk of death or recurrence of breast cancer among women
  • May reduce the risk of colorectal cancer in postmenopausal women
  • Improved cognitive function, particularly verbal memory and in frontal lobe function
  • Omega-3 fatty acids, like those found in some algae and oily fish are also found in soya beans
  • Cholesterol-lowering food, along with other heart and health benefits.
  • Soya beans contain a high level of phytic acid, which has many effects including acting as an antioxidant and a chelating agent, for reducing cancer, minimizing diabetes and reducing inflammation.