Soy has more and more followers around the world. Originally from Asia, this legume contains complete proteins, which can replace meat for vegetarians. In addition, soy does not contain cholesterol and it contains good quality fats including monounsaturated and polyunsaturated acids. In the kitchen, it offers a multitude of possibilities and lends itself to all combinations.
Characteristics of soybeans
- Excellent source of vegetable protein;
- Rich in phytoestrogens;
- Source of unsaturated lipids;
- Promotes cardiovascular health;
- Good source of vitamins and minerals.
Nutritional and caloric values of soybeans
|Nutritional value of some soy products|
|weight/volume||Soybeans, 100g||Tofu nature, 100 g||Salted soy sauce, 100 ml|
|Proteins||34,5 g||13,4 g||7.1 g|
|Carbohydrates||20,8 g||2,9 g||3,6 g|
|Lipids||19,2 g||8,5 g||0,1 g|
|Dietary fiber||13 g||0,1 g||0,86 g|
Focus on the micronutrients contained in soy
Among the nutrients contained in good quantities in soybeans, we can mention the following:
- Iron. Soy, especially tofu, is an excellent source of iron. Each body cell contains iron. This mineral is essential for the transport of oxygen and the formation of red blood cells in the blood. It also plays a role in the production of new cells, hormones and neurotransmitters. It should be noted that the iron contained in plants is not as well absorbed by the body as the iron contained in foods of animal origin. However, the absorption of iron from plants is favored if it is consumed with certain nutrients, such as vitamin C;
- Zinc. Soy is a good source of zinc. Zinc participates in particular in immune reactions, in the production of genetic material, in the perception of taste, in the healing of wounds and in the development of the fetus. Zinc also interacts with sex and thyroid hormones. In the pancreas, it participates in the synthesis (production), storage and release of insulin;
- Calcium. Soy, especially tofu made from calcium sulfate, and fortified soy beverages are a good source of calcium. Calcium is by far the most abundant mineral in the body. It is mainly stored in the bones, of which it is an integral part. It contributes to the formation of the latter, as well as that of the teeth, and to the maintenance of their health. Calcium also plays an essential role in blood clotting, maintaining blood pressure and the contraction of muscles, including the heart.
The benefits of soy
With its remarkable nutritional profile, soy is a healthy ally that deserves its place in a varied and balanced diet. Numerous studies have highlighted its anti-cancer properties and its positive effects on cardiovascular health, in particular due to its quality fat content.
Soy contains phytoestrogens, including genistein, daidzein and glycitein, molecules that resemble estrogen, a female hormone synthesized by the human body. In the body, phytoestrogens and estrogens would compete. These would therefore have the ability to replace part of the estrogen. As estrogens would contribute to the proliferation of certain types of cancerous cells, phytoestrogens would lead to their destruction, thus reducing the size of breast tumors. The risk of breast cancer would therefore be lower when women have higher levels of phytoestrogens in the blood. This effect was noticed only in premenopausal women.
In addition, the studies that demonstrate a protective effect of soy on breast cancer have, for the most part, been carried out in Asian women who consume five times more phytoestrogens than North American women and more soy in fermented form (tempeh , miso, natto). It is therefore necessary to be vigilant with regard to the results of these studies.
Finally, phytoestrogens have also been studied in relation to increased hot flashes during menopause, a sign of declining estrogen levels. A meta-analysis of several scientific studies has shown that taking 30 to 80 mg per day of isoflavones, a type of phytoestrogen, reduces the frequency of hot flashes by 21% in postmenopausal women.
The American Heart Association encourages the consumption of soy products which may benefit cardiovascular health due to their nutritional qualities. However, no large study has shown that high intakes of soy protein have beneficial effects on blood cholesterol levels. The positive effects on heart health would be partly due to the fact that by consuming soy, we reduce our consumption of foods of animal origin such as red meat, for example, which contain saturated and trans fats and which are harmful to the heart.
Soy and sex hormones, what links?
A meta-analysis of several clinical studies assessed the effect of soy and isoflavone consumption on testosterone levels and other sex hormones in men. The results show that soy consumption has no impact on sex hormone levels. Studies on the effects of soy consumption on bone mineralization or the risk of osteoporosis and prostate cancer are not yet conclusive to make recommendations.
Among the foods richest in isoflavones, we can mention the following:
- Soy flour ;
- Edamames ;
- Tempeh ;
- Tofu ;
- Soy beverages;
- Miso ;
- Textured soy protein;
- Soja sauce.
How to choose the right soy?
Soybeans belong to the large Fabaceae family, just like the vast majority of legumes with which they also share some similarities from a nutritional point of view. Originally from China, soy has been grown in Asia for a very long time and is an integral part of Asian cuisine. In France, it is now easily found in supermarkets and in organic stores in various forms.
Soy ID card
- Family: Fabaceae;
- Origin: China;
- Season: available all year round;
- Color: light brown;
- Flavor: neutral.
Choosing Soy Wisely
The immature green beans of soybeans (known as edamame – literally “bean on branches”) are now found in the frozen aisle of supermarkets. Since the grain of soybeans does not lend itself to cold pressing, only highly refined oil can be found on the market.
For optimal preservation
Dried grains can be kept for one year in a dry and cool place. To prevent it from going rancid, keep the flour preferably in the fridge or freezer. Fresh soy freezes in its pod after being blanched for five minutes in boiling water and cooled in ice water. Dry the pods well before freezing them. Milk, tofu, natto, and tempeh will keep for a week or two in the fridge.
Finally, soy sauce, miso, fermented black beans can be kept for a year or more, cool and dry.
How to prepare soybeans
In cooking, soy offers many possibilities and can be incorporated into everyday recipes in all its forms: grains, soy drinks, fermented soy, soy sauce, tofu, etc. Its relatively neutral taste benefits from being associated with foods rich in flavor and with spices. Soy-based drinks, flavored or not, are becoming more and more popular and allow the creation of desserts that are both gourmet and nutritious.
On the market, there are varieties with yellow seeds and black seeds. The latter are tastier and allow more varied uses; but if you want to make your own milk, you will preferably choose yellow soybeans. It takes about three hours to cook the grains in water after soaking for one hour. To save time, they can be cooked in a pressure cooker. They will be served with rice and sautéed vegetables.
- Kinako is prepared by first soaking the grains for six hours, then roasting them on a baking sheet in the oven until they turn a nice golden brown color. They are eaten as they are with a little salt;
- Like mung beans, soybeans can be sprouted and then used in various Asian dishes;
- The finely ground grain gives a flour which may contain, depending on the transformation process, 12% to 65% protein, and whose oil content will vary from 0.5% to 24% depending on whether it is whole, semi-defatted or degreased. It is used to bind sauces, to make cakes, muffins and cookies. Because of its high protein content, many processed foods are fortified with soy flour;
- Edamame: the Japanese eat the green beans as a snack. They cook them with their pods for a few minutes in boiling water. They then bring the pod to their mouths and squeeze it to extract the grain.
Soy-based drinks, an asset in the kitchen
Soybeans are simply pressed after cooking to extract a milky substance that can be used in all dishes where cow’s milk would normally be used: pastries, smoothies, sauces, flans, soufflés, puddings, etc
Soy beverages fortified with vitamin A, D, B12, thiamin, zinc, calcium, and unsweetened are the plant-based beverages that have the nutritional profile most similar to plain cow’s milk. In fact, they contain about the same amount of protein as cow’s milk and similar amounts of vitamins and minerals. Since these drinks are made from plant-based ingredients (soybeans) unlike milk which comes from dairy cows, they contain no trans fats and cholesterol and less sugar (6-7 grams per cup).
The Japanese recover the skin (yuba) which forms on the surface of the milk after it has been heated. They eat it as it is or use it to make rice or vegetable rolls. By using a wide and shallow pan, you can collect a good amount of skins. Simply warm the milk after each collection and let it cool for five to seven minutes. Take the skin with a stick slipped under the surface and hang it to drain.
What to do with tofu?
Drained milk gives tofu, a kind of vegetable cheese which has little flavor in itself, but which can absorb that of other foods or condiments. It is added to soups, salads, sautéed dishes. It can be barbecued or deep fried.
- Use firm tofu for stir-fries and grills, medium firm for soups and silken for cream or pudding dishes. There is also spicy tofu, colored with natural pigments, flavored with red wine or rice wine, etc. ;
- The simplest and most common way to eat tofu in Japan is to cut it into cubes (eight per tofu loaf) and simmer it for a few minutes in a few centimeters of water or broth and serve it with a soy sauce and the following condiments: roasted and torn nori seaweed, toasted sesame seeds, finely chopped green onion, grated ginger and bonito flakes. The tofu is ready when it rises to the surface of the water;
- Beaten with oil and vinegar, it can replace mayonnaise. It can also be made into a sauce that will accompany vegetables (asparagus or broccoli, for example) by passing it through a blender with tahini, a little honey, soy sauce and rice vinegar;
- Blended with soy sauce, tahini, lemon juice, shallot and sweet pepper, it will make an excellent dip to serve with raw vegetables;
- In summer, cool it by soaking it in ice water. Served with soy sauce or miso, a piece of grated ginger root, finely pressed garlic, strips of nori, sesame salt, grated or minced vegetables, it’s a meal in itself;
- In the guacamole, replace the avocado with tofu;
- Place 2 cm thick slices of tofu under the broiler for about three minutes. Spread on the surface of the slices a mixture of cooked spinach, tahini and white miso that we will have passed through the blender and return to the oven for two minutes. Garnish with thin strips of lemon rind;
- Tofu and scrambled eggs: crumble tofu and cook in a pan with eggs while stirring. Add a julienne of carrot, snow peas and shiitake slices spent two minutes in boiling water and season with a little soy sauce.
Fermented soy products
- Miso: reduced to a purée, then fermented for many months with or without cereal, soy is transformed into miso, a must in Japanese cuisine. It is mainly used to make soups, by diluting it in a seaweed-based broth, or as a sauce to give flavor to vegetable or tofu dishes;
- Soy sauce (shoyu or tamari): fermented with or without cereal, then put in brine, soy gives this unique sauce that no Asian preparation can do without. It is added to cooked dishes or used as a condiment after marinating ginger, chives, horseradish or wasabi, lemon, lime, or finely grated vegetables such as daikon or white turnip. Add it to vinaigrettes or in a yogurt sauce with which to coat a fish;
- Natto: by inoculating the cooked grains with a specific bacterium, we obtain after a day or two this preparation whose flavor is reminiscent of that of blue cheese, and the texture that of mozzarella. It is added to rice, miso soup, tofu or in omelettes. It is made into a dip or an ingredient in tempura;
- Tempeh: Cooked soybeans are seeded with another type of bacteria, then left to ferment for 24 hours. It is then shaped into patties, dumplings, etc. In the West, tempeh is often presented to look like ground meat patties or sausages. It can be added to soups, sauces, chilis. It is pan-fried or steamed, grilled, sautéed or marinated;
- Fermented Black Beans: Soybeans are subjected to a fermentation process that gives them a pronounced color, then preserved in salt. It can be dark soybeans, but not necessarily, the color resulting from fermentation. It is used as a condiment to season dishes. Most cooks recommend soaking them in water for half an hour (to desalinate them) before using them, but others say they lose much of their quality when rinsed. In the kitchen, only a few grains are used at a time, which are minced. Delicious with fish;
- Fermented tofu: very fragrant, like all other fermented products, it is used in small quantities to spice up a bland dish.
Contraindications and allergies to soy
Soy is overall nutritious and good for the health of the body. In some cases, however, its consumption is not recommended, in particular because of its impact on hormonal activity. Other studies are still underway on the effects of soy in women with endometriosis or hormonal pathologies, among others. Until we know more, soy should be consumed in moderation and as part of a varied diet.
History of breast cancer
It should be noted that in women with breast cancer or who have had breast cancer in the past, taking concentrated sources of soy such as powders and supplements is not recommended. On the other hand, moderate consumption of soy foods is not discouraged and some results even suggest an improvement in the prognosis with the consumption of one to two servings of soy products per day.
Soy and hypothyroidism
Decreasing the absorption of iodine, soy may harm the normal functioning of the thyroid gland or interfere with the absorption of thyroid medication. Soy products are therefore part of the “goitrogenic” foods along with cruciferous vegetables, millet, cassava and peanuts. On the other hand, the latest studies have shown that soy produces goitrogenic effects only if the person is deficient in iodine. Therefore, individuals with goiter due to iodine deficiency should not consume soy products.
People with hypothyroidism on medication should still avoid consuming soy while taking their medication. You should also know that soy does not affect the thyroid gland of people with a normal state of health.
History and anecdotes
Should we write “soya” or “soya”? One or the other, according to linguists. The term “soya” is inspired by the English soy, itself borrowed from Japanese, while the term “soya” comes from German. In the French-speaking communities of North America, the English derivative has been adopted, while in the French-speaking countries of Europe, the German form has been chosen.
A little history
Researchers have speculated that the soy bean was cultivated as early as 9,000 years ago, but archaeological excavations have yet to confirm this. It is believed to come from central or northern China, possibly Manchuria.
Along with rice, wheat, barley and millet, soybeans were among the five sacred grains that gave birth to Chinese civilization and enabled its expansion. Hence the sumptuous ceremonies organized by the various emperors during the sowing. Over the centuries, poets have never ceased to praise its merits and the services it rendered to humanity.
Between the 2nd century BC and the 15th or 16th century, soy will be introduced in the majority of Asian countries – Japan, Indonesia, Philippines, Vietnam, Thailand, Malaysia, Burma, Nepal and northern India – where the many local varieties will be selected. Despite its popularity in Asia, its culinary interest eluded Westerners until the end of the 16th century. Indeed, the first European travelers who had gone to these countries being unable to establish a relationship between products such as “milk” and “cheese” which were consumed there and the grain of the exotic plant which they had brought back to cultivate it in their botanical gardens.
In America, soy will be cultivated for the first time at the end of the 18th century, by a farmer from Georgia, but its cultivation will remain marginal until the end of the 19th century. We will then gradually become aware of its very great value. It is used as animal feed, cheap substitute for meat and in multiple industrial applications: fuel, plastics, adhesives, paint, printing inks, fermentation medium for the production of antibiotics, emulsifier, etc.
If this is a first crop of soybeans, inoculate the seeds with an appropriate nitrogen-fixing bacterium, genus Rhizobium. Sow after the last frosts, at a rate of 18 to 30 seeds per meter. The black-grained variety “Black Jet” is particularly suitable for northern regions. It takes about 104 days from sowing to harvesting the dry seed. Uproot the plants, hang them in a dry place to complete the drying.
A few varieties have been selected for green harvesting, which is done after 75 to 90 days. Harvest when the pods are just starting to turn yellow. Leave the grains in their pods until ready to cook, they will keep fresher.
Ecology and environment
Virtually unknown in the West a hundred years ago, soy has become an essential ingredient in the food industry. It is estimated that 60% of processed products intended for human consumption contain one or another of the by-products of this plant. In addition, it is displacing all other legumes traditionally used in animal feed.
As a result, it is now the most widely grown legume in the world, and every year more and more arable land is devoted to it. We are therefore witnessing an erosion of the biodiversity of cultivated species. Added to this is the genetic erosion of soybeans themselves since, of the thousands of varieties listed, only a handful are grown, which opens the door wide to massive infestations of insect pests and epidemics. fungal or bacterial diseases. Finally, transgenic soya tends to impose itself everywhere on the planet, with the risks that GMO technology entails for ecosystems.
Although there is no evidence that GMOs are harmful to health, environmental risks are present. There are various solutions that could contribute to reversing this trend: avoiding processed products as much as possible, preferably choosing soy products from organic farming, varying your sources of legumes (peas, chickpeas, lentils, beans, bean, cowpea, amber) and consume less meat or, at least, consume meat from animals whose diet is not exclusively centered on soy (and corn).