Soybeans are a variety of edible bean belonging to the legume family. They are native to East Asia but are now cultivated and consumed across the globe in a wide range of climates. Soybean products are used for human consumption, animal feed, and a variety of nonfood consumer and industrial products. Soybeans are sold fresh, frozen, canned, and dried and can be cooked and eaten similarly to other types of beans.
- Nutritional Information: a complete protein
- Origin: East Asia
- Uses: tofu, vegetable oil, soy sauce
What Are Soybeans?
Soybeans, also known as soya beans, are the beans of a species of legume, Glycine max. Although Chinese farmers began growing soybeans more than 5,000 years ago, it wasn't until the 1800s that they were planted in the United States. Currently, the U.S. is responsible for 50 percent of soybean production. Soybeans are harvested either green or mature and then sold fresh or dried. The immature soybeans are called edamame; they are smooth, crisp, and firm, retain their texture after cooking, and are sold frozen and fresh. Mature soybeans are a light brown color and are available in and out of the pod; dried are smaller and require soaking and cooking.
The small, round soybean seeds have a tiny dark spot (called hilum) and are most often a pale yellow color. They are available as beans, although sometimes are offered in the pods, which contain three beans each.
Soybeans vs. Edamame
Soybeans are also sometimes referred to as edamame, but it is just one type of soybean that is technically edamame. The term is reserved for immature soybeans that are harvested when green, which is about 30 days before the pods turn brown and become dry. Edamame can also refer to the dish comprised of steamed immature soybeans. Edamame are large with a sweet taste that lacks the "beany" flavor often found in mature beans.
There are over 2,500 varieties of soybeans; they range in color from white (the most common) to black, brown, and green. Each variety is used for different purposes. Green, for example, is often used in the manufacturing of roasted soy flour (kinako) and to make green tofu and natto, while black is simmered and eaten as part of the traditional Japanese New Year meal. Edamame can be any color soybean as long as it has been harvested when immature.
Soybeans have been a staple food in many parts of the world for thousands of years, and over time, several different products have been made using soybeans, allowing them to be enjoyed in a variety of ways. Some of the most common products produced with soybeans are tofu, soy milk, soy sauce, tempeh, TVP (textured vegetable protein), and soy flour. Approximately 85 percent of soybeans grown around the world are used to make vegetable oils that are either sold to consumers or used commercially. Soybeans are also roasted and salted and sold as snacks.
Different-sized soybeans serve different functions. Large soybeans are used for cooking, and the small are fermented. Medium-sized soybeans are used to make processed foods.
How to Cook With Soybeans
Raw soybeans are unsafe to eat as certain chemicals can cause digestive problems and long-term health issues. These chemicals are destroyed by heat, so soybeans must be cooked with moist heat (steaming, boiling, poaching, etc.) prior to consumption.
Like other dried beans, soybeans need to be soaked and cooked before using in a recipe. Soybeans, however, should be stored in the refrigerator while soaking to prevent fermentation, and have the longest cooking time of any dried bean—up to three hours. Even after that, the beans will not get soft, but will be tender to the bite, and can be added to soups and stews and incorporated into recipes.
Edamame can be cooked in a few different ways, including boiling, steaming, microwaving, and pan-searing. Canned soybeans simply need to be rinsed before using.
What Do They Taste Like?
Soybeans barely have any taste and don't absorb much of the flavors of the ingredients they are cooked with. The exception is edamame, which has a buttery flavor and richness with sweet and nutty undertones.
Since soybeans are mild tasting and need seasoning, they are often combined with several other flavorful ingredients in a recipe.
Where to Buy Soybeans
Soybeans can be found in health food stores, specialty markets, and the natural food section of the supermarket. They are available in cans but when dried are sold in packages and in bulk. Edamame is sold fresh and frozen in and out of the pods, and the bean is also sold in cans. Organic and non-GMO varieties are also available. The beans or pods should be firm, plump, and blemish free. If buying in bulk, be sure the bins are covered and that the product is replenished frequently.
Fresh soybeans and edamame should be stored in the refrigerator and used within two days. They can also be frozen and kept for several months. Dried soybeans can be left in an airtight container in a cool, dry place for up to a year, while canned will last a year or more.
Nutrition and Benefits
Soybeans provide all nine essential amino acids and are therefore considered to be a complete protein. In combination with low levels of saturated fat and cholesterol, this makes soybeans an ideal substitute for animal-based protein sources and a heart-healthy alternative to red meat.
Soybeans are also an excellent source of dietary fiber, which promotes healthy gastrointestinal function, reduces bad cholesterol, and is correlated with a reduced risk of cardiovascular disease. The beans are also a good source of isoflavones (phytochemicals), which may help prevent postmenopausal bone loss and certain types of cancers. In addition, soybeans contain good amounts of potassium and iron, as well as manganese, phosphorus, and selenium.
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