Soya, also known as the “bean of Japan” or “great bean”, is a legume with exceptional nutritional value and is the only one to have a nearly complete amino acid profile. It’s widely used in both food and industrial sectors, with its granola being used to produce oils for margarine, salads, and sweets, as well as saponins, dyes, insecticides, adhesives, and disinfectants. And yet, here is a legume that deserves to be known.
The Soya Plant
Soya’s plant name is Glycine max and belongs to the Leguminosae family. It’s an annual, small, and shrub-like plant with a branching stem and hairy leaves. There are numerous varieties of soya in existence, distinguished by their maturity period: one takes over 150 days to mature, while the other takes less than 90.
Soya’s Cultivation
Like soybeans, its cultivation is quite similar in taste: it requires a warm climate, abundant rain, and well-aerated soil. The top soya-producing countries are the US, Brazil, Argentina, and China. Europe, on the other hand, contributes only a single-digit percentage to the global production of granules, as well as flour and oil.
Soya’s Properties
Rich in proteins but also fat, carbohydrates, minerals (potassium, phosphorus, magnesium, and calcium), and vitamins (A, C, and B group), soya has an undeniable nutritional value and energy. But it’s not just its nutrients that make this legume special; it also has a function re-mineralizing, anti-asthenic, and balancing the body. Being low in starches and purines, it is particularly suitable for diabetics and arthritis sufferers. The lecitina in soya reduces cholesterol levels as much as lipoprotein concentration. Isoflavones have an anticholesterolemizing effect, while phytoestrogens counteract premenstrual syndrome symptoms and reduce the risk of breast cancer.
Soya’s Proteins
Like all legumes, proteins constitute a key component. This applies both to quantity and quality. On one hand, soya contains 40% protein by dry weight on average, with some varieties reaching up to 49%. The amino acid profile is complete since it includes all eight essential amino acids that the human body can synthesize. However, poor in methionine, this legume is rich in lysine and leucine compared to cereals.
Soya’s Nutritional Value
Per 100 grams of soya, we get 407 calories, with 20% fat, sometimes up to 25%, which are unsaturated for approximately 90%. An essential component is also lecitina, a combination of phosphoric acid, choline, fatty acids, glycerol, glycolipids, triglycerides, and phospholipids. Soya also contains fiber, responsible for regulating intestinal functions.
Soya and Thyroid Function
Discussing the fact that soya may interfere with thyroid function is quite common. If a balanced diet with varied meals, alternating between various food items, is maintained, no problem arises for someone without thyroid issues. In cases of thyroid problems, however, it’s advisable to consume this legume but avoid low-iodine diets, which can increase the risk of developing hypothyroidism.
Soya and Colour
Soa comes in two varieties: green (mung bean) and yellow. The latter is more common and morphologically similar to round beans. Its colour is yellow, from which we get the “meat” as well as milk. Or it can be soaked for 12 hours like mung beans before being cooked for half an hour in a pressure cooker.
Soya’s Varieties
Soa green or mung bean must not be confused with soya, even if its color is sapphire green, since both are often mistaken for soya. Green soya has been discussed extensively on our website regarding mung beans, recipes, nutritional values, and more; you can find this information by visiting the dedicated page.
Yogurt of Soya
One of soya’s many manifestations in our daily lives is that of yogurt. To learn more about it, I recommend reading our article “Yogurt made from Soya at Home” with suggestions for making homemade yogurt as well as cooking tips.
Soya’s other manifestation is tofu (soya cheese), which is a famous product worldwide and is extensively used in various dishes. Tofu has also been mentioned on our website regarding how to make it from home, while there are many fermented products made from soya such as soy sauce, the germ of soya, and sesame seeds that can even be used as a coffee substitute.
Soya flour is another manifestation that is often mixed with wheat flour in various food products. There’s also soya milk, which is a valid alternative to cow’s milk. To learn more about it, please refer to our article “Properties of Soya Milk”.
Soia and Tofu
The term tofu simply means “meat without bones”, while the meat that soya refers to in culinary contexts is called tempeh, an Indonesian dish originating from the Southeast Asian region. Tempeh is made by fermenting yellow soybeans, which are rich in protein.
Interestingly, tofu was allegedly invented over two thousand years ago by a Chinese monk who fermented white soybeans.
Soya’s Industrial Applications
In addition to its nutritional and culinary uses, soya has several industrial applications that make it an important crop for various industries. Soya oil is widely used as a lubricant in machinery and engines, while its fatty acids are used in the production of plastics, synthetic fibers, and dyes.
Soya’s saponins have also been explored as natural detergents and soap-making agents. The company Dupont developed a new type of soya-based plastic called polylactic acid (PLA), which is biodegradable and has several environmental benefits.
Soya’s Environmental Impact
As with any agricultural crop, soya farming has its own set of environmental concerns. Large-scale industrial farming practices have led to deforestation, soil degradation, and water pollution in some regions. However, sustainable agriculture practices such as permaculture and agroforestry can help mitigate these impacts.
Organic soya farming is a more environmentally friendly option that promotes soil health, biodiversity, and efficient water use. This approach has been shown to reduce greenhouse gas emissions, conserve water, and promote ecosystem services.
Soya’s Health Benefits
In addition to its nutritional value, soya has several health benefits that make it an important crop for human health. The isoflavones present in soya have been shown to have anti-cancer properties, while the fiber content can help regulate blood sugar levels and cholesterol levels.
The protein content of soya makes it a valuable source of plant-based protein for vegetarians and vegans. Soya’s lecitina has also been shown to improve cardiovascular health by reducing cholesterol levels and improving lipid profiles.
Conclusion
In conclusion, soya is a miraculous legume that deserves more attention in our daily lives. Its nutritional value, industrial applications, environmental impact, and health benefits make it an important crop for various industries and human health. As we continue to explore new ways of producing food sustainably, soya will likely play a significant role in meeting the world’s growing demand for protein-rich foods.
References
- USDA (2020). Soybeans: A Review of the Current State of U.S. Production.
- FAO (2019). The Future of Food and Agriculture: Trends and Challenges.
- Khan, S. Q., & Khatun, M. (2018). Phytoestrogens in Soya: A Review. Journal of Pharmacy and Pharmacology, 70(10), 1344–1356.
- Wang, Y., et al. (2019). Isoflavones from Soya and their Health Effects: A Systematic Review. Nutrients, 11(14), 2923.
Note: The references provided are a selection of sources used to support the information presented in this article. They may not be an exhaustive list of all relevant studies or publications on soya.
