1. High in Protein
Soybean (Glycine max L.) is one of the most important high-quality vegetable protein crops (Singh et al. 2007) with a well-balanced amino acid composition and outstanding functional properties such as water binding, emulsifying action and oil absorption. Its high nutritional value and versatility make it a popular food for humans and an ideal plant protein source for people on vegetarian or low-fat diets. The soybean is also a valuable raw material for the manufacture of many other products such as medicines, animal feeds and industrial chemicals (Fehr et al. 2002).
The soybean is rich in high-quality proteins, essential fatty acids, vitamins and minerals. The soybean is particularly rich in the amino acid lysine, which makes it an excellent source of dietary protein for people who do not eat meat or dairy products. It is also a good source of folic acid, vitamin B6 and vitamin B12. The soybean contains high amounts of phytochemicals called isoflavones, which are similar to female sex hormone estrogen and act as anti-oxidants and help reduce cholesterol levels in the blood (Reynolds et al., 2006).
Protein contents vary between different soybean genotypes. The proteins in soybean are mainly composed of the storage proteins b-conglycinin (7S) and glycinin (11S). Protein quality in soybeans is affected by the environment, including temperature, photoperiod and nitrogen availability. The protein content of soybeans can be improved by genetic selection, plant breeding and environmental conditions (Bellaloui et al., 2011).
The protein in soybeans is highly digestible, which means it can be absorbed easily by the human digestive tract. However, its nutrient density is reduced by the presence of anti-nutritional factors such as trypsin inhibitor, phytic acid and phenols. The levels of phytic acid in soybeans can be reduced by boiling, sprouting and fermenting the beans. Phytic acid chelates mineral nutrients such as zinc and iron, reducing their availability to the body (Liener, 1981).
2. Low in Calories
A typical soybean contains only about 230 calories, making it low in fat and rich in nutrients. Soybean-based foods such as tofu, tempeh, soy milk and soy bread are often used in vegetarian diets, as they are high in protein and offer many health benefits including improved bone health, lower risk of heart disease and cancer. It is important to note that soya beans are also low in allergens, meaning those with allergies can enjoy foods made from soybean lecithin and soya bean oil without worrying about allergic reactions.
3. High in Fiber
Black soybeans (Glycine max L.) are a variety of the more common yellow soybeans and can be eaten in the same way as other legumes, either dried and reconstituted or canned. Like other legumes, they are a high-fiber source and also provide the body with protein. They can be used to make a soy milk, which is often made with just water, and also used in many soy products such as tofu and tempeh. The beans can also be roasted to make soy bean tea. One cup of black soybeans provides 11 grams of protein and 3 grams of fiber.
Compared to other beans, black soybeans have lower levels of fat. They have a low glycemic index and, when cooked, they release soluble fiber which can slow down the rate at which blood sugar rises after eating. They also contain healthy unsaturated fats, which can help reduce cholesterol.
A diet including soya beans is a great source of dietary fiber, protein, and many vitamins and minerals. They are especially rich in iron, potassium, magnesium, copper, manganese and riboflavin. They are also an excellent source of folate, which can help prevent heart disease and cancer.
Soybean proteins are considered a complete protein, meaning they contain all the essential amino acids needed by the human body. Moreover, they are rich in omega-3 and omega-6 fatty acids.
Soybean crops are a critical component of smallholder agriculture in sub-Saharan Africa, where most farmers have less than two hectares of land. They produce a wide range of goods and services and have been credited with reducing poverty and improving food security in the region. However, soybean farming can be problematic for those with allergies. People with a soy allergy can experience symptoms such as vomiting, diarrhea, wheezing and hives. Some soy products may be cross-contaminated with gluten, which can trigger a reaction in those with celiac disease or non-celiac gluten sensitivity.
4. High in Minerals
The high mineral content of soybeans makes them a valuable source for soil fertility improvement. The roots of the plant contain bacteria called rhizobia that convert atmospheric nitrogen into a form readily available for other plants [2, 23]. Soybean has a natural function to improve soil fertility by biologically fixing nitrogen, which helps save farmer’s money on the cost of inorganic fertilizers [2, 26]. This non-market benefit can be a major motivating factor for smallholder farmers to invest in soybean production.
In a study conducted in Ghana, a mixed research approach was used to survey the views of farmers on the economic and non-market benefits of soya bean production. Qualitative methods such as key informant interviews and focus group discussions were employed to collect data on farmers’ perceptions of the market and non-market benefits of soybean production. Quantitative surveys were also conducted to measure the economic efficiency of soybean production by assessing the costs of producing soybeans, the amount of soybeans sold and reserved for home consumption, and the prices of soybeans on the market.
Unlike other legumes, soybean is highly responsive to changes in the environment during the growing season. Rainfall intensity and timing is an important factor in the accumulation of macro- and micronutrients in seeds. Soybean seeds accumulated more of the nutrients N, P, Ca, Mg, Zn, Cu, and Mn in years with low rainfall in June and in the first two-thirds of August, compared to the year with more evenly distributed rainfall. [35]
In a study of the response of soybean to nitrogen treatment, it was found that the time of application of nitrogen is an important factor in the yield of soybeans. The highest soybean seed yield was obtained when a quarter of the nitrogen was applied before sowing and the rest at the beginning of the seed-filling stage. Moreover, the genetic factor also has an effect on the uptake of nitrogen by soybeans. The Merlin cultivar accumulated more of the macro-nutrients N, P, and K and less of the micro-nutrients Cu and Fe than the Amandine variety.
5. Low in Fat
Despite the fact that beans contain some fat, they are very low in total fat and provide a significant amount of healthy unsaturated fats. Beans are a particularly good source of the omega-3 fatty acid a-linolenic acid. Beans have a moderately low glycemic index, which makes them a suitable food for individuals with diabetes.
Soybeans are a staple in many Asian diets. They are high in protein and fibre and low in calories and fat. They are also a good source of iron, zinc and folate. Soybeans are also a source of hormone-like substances called isoflavones, which have been linked to reduced risk of cancer and improved bone health.
Edamame are soybeans that are harvested while still green and typically served as an appetizer or snack. They are high in protein and dietary fibre and contain good amounts of the plant-based omega-3 fatty acids. They are a very good source of isoflavones and a variety of vitamins and minerals.
Dry soybeans are cooked and processed into a wide variety of foods including tofu, soy milk, edamame, tempeh, soy sauce, miso and other Asian condiments. Soymilk is an excellent alternative to cow’s milk for people who are lactose intolerant. It is also high in protein and a good source of calcium, phosphorus, potassium and vitamin B6.
Soybean products are a popular substitute for meat in vegetarian and vegan diets. They are a good source of protein and other nutrients including folate, iron, calcium, niacin, selenium and thiamine. Some studies have suggested that soybeans may help to reduce the risk of heart disease, lower cholesterol levels and prevent brittle bones, but more research is needed.
