Soybeans (Glycine max)
FABACEAE, Legume Family
A plant perhaps destined to save the world from starvation is the soybean (Glycine max), which hails from China. This plant is sometimes called the "king of the legumes," because the seeds can contain up to 44% protein. This protein can be used for flour and, therefore, a protein fortifier for anything that uses flour. From the seeds comes soybean oil, which is a drying oil used in paints and which has many excellent uses. The roots of the plants are loaded with nodules, in which nitrogen fixation occurs. This plant grows as an annual under many field conditions; and soybeans can be used not only as a valuable cash crop, yielding at least two products, but also as a crop that resotres the fertility to the soil for the next crop, such as a grain.
Soy protein is the key product. For centuries this has been made into bean curd (tofu) and flour (miso, in Japan), particularly in eastern Asia, but over the last 35 years, soy protein has been widely used in the United States. Tofu has become an important ingredient in baby foods and is a substitute for baby formula for those children who are allergic to other milks. Researchers discovered that the protein can be spun into fibers and then made into fake meat, imitation bacon, textured vegetable protein, and the like. From a field of soybeans, one can get 15 to 20 times as much protein as beef raised on the same area. This protein made soybean second in importance as a crop plant in the United States Corn Belt, even though it was a relatively minor crop three decades ago. For example, in 1940 the annual production was ten million tons, whereas in 1972 world production was more than 60 million tons. Recently the annual production easily exceeds 100 million tons. World soybean production per person has increase from 7 kilograms in 1950 to more than 20 kilograms now. Brazil is also a major producer of soybeans.
Soy sauce is made from cooked soybeans, wheat flour, salt, and water, together which is fermented by a yeast. In Asia, aging is done in stone crocks, but in the United States, soy sauce is often aged chemically.
The worst thing about soybeans is that most strains contain a hydrolytic enzyme in the fresh seeds, which interferes with protein digestion by blocking an enzyme in the stomach. Plant geneticists are using their molecular techniques to cut this enzyme out of important soybean strains using the procedures of genetic engineering.