As we all know, soybean has a high content of protein, an appropriate and complete proportion of amino acids, and excellent structural quality of essential amino acids. Rich in brain-strengthening, brain-benefiting and brain-nourishing ingredients; Rich in calcium, phosphorus and iron, it is very beneficial to children who are growing up, the elderly with osteoporosis and those with iron deficiency anemia. However, how to eat soybeans to achieve the best nutritional and therapeutic effects?
I. Processing
The utilization degree of soybean nutritional advantages is directly proportional to the processing degree. Soybean is a high protein plant, and the digestibility of protein before processing is very low. The finer the soybean processing, the higher the utilization rate. For example, the protein digestibility of fried beans is 60%, cooked whole beans are 68%, cooked soybean milk is 85%, and the digestibility of tofu, tofu and soybean powder is as high as 95%. Therefore, making soybean into industrial food can better play its role.
Soybeans must be cooked. Some active ingredients of raw soybean and raw soybean milk, such as trypsin inhibitor, phytohemagglutinin, phytic acid, saponin, etc. It has special effects such as anti-cancer, but it also has adverse effects such as inhibiting nutrient absorption, stimulating digestive tract mucosa and causing allergic discomfort to sensitive people, so it was previously called anti-nutritional factor. Modern research has proved that these active ingredients can be reduced to harmless level after cooking or proper processing, and can still play a role in dietotherapy.
It should be noted that processing will change the nutritional composition of soybeans, such as excessive heating will cause the loss of water-soluble vitamins; Soymilk and tofu do not contain insoluble cellulose; The protein digestibility of raw beans is low, but as an anti-cancer diet, the effect will be better if a variety of active ingredients cooperate with each other. Fermented bean products have increased amino acid content and high digestibility, and also contain nutrients such as VB 12 that soybean itself does not contain, but almost no soluble dietary fiber oligosaccharides. Therefore, the same soybean product should not be too partial to one of them, but should be diversified and balanced, which makes the process of soybean industrialization more urgent.
Second, balance.
A very important concept in a balanced diet is the nutritional complementarity of protein. This nutritional term means that two or more different protein can make up for the deficiency of amino acids, thus improving the overall absorption rate and achieving higher nutritional value. Among them, the mutual promotion of animals and plants and protein is also called "the complementary action of animals and plants", which is an important standard of balanced diet. Soybean occupies a very special position in a balanced diet. It is the only plant complete protein, which can have a good nutritional complementary effect with almost all animal and plant proteins. Fresh milk and soybean milk are typical complementary effects of animals and plants. Except protein, casein in milk can promote the absorption of calcium in soybean milk, iron in soybean milk can make up for the lack of iron in milk, and soybean lecithin can reduce the absorption of fat and promote fat metabolism, so that people can keep a good figure without pursuing skim milk with poor taste and high price. Therefore, fresh milk soybean milk is the best drink for men, women and children. Soybeans are the best source of protein for vegetarians. The protein nutritional complementarity between soybeans and cereals (such as cereals and wheat) is also commendable. In China, cereals and pasta are staple foods, which easily lead to the lack of lysine and threonine. Eating soybean together with rice and flour can not only supplement these restrictive amino acids, but also balance the amino acids with relatively low sulfur content in soybean. This is also strongly advocated by the balanced diet proposed by the China Food and Nutrition Advisory Committee.
Third, milk and soybean milk.
Now there is a popular saying in society: "Men drink milk and women drink soybean milk". This statement is scientific, because soybean contains phytoestrogen isoflavones, which have special physiological effects on women, such as regulating endocrine, making skin fit, preventing breast cancer, and preventing hot flashes in menopause. But it doesn't mean that men drinking soy milk or women drinking milk will do any harm. Especially when men see the propaganda of soybean estrogen, there is no need to have resistance. Soybean is the only effective source of phytoestrogen (isoflavone). The mechanism of isoflavones acting on human body is to replace the receptor position of endogenous estrogen in human body, regulate hormone level and reduce the risk of hormone-related cancers, such as breast cancer. Estrogen receptors also exist in men, and isoflavones can also have beneficial physiological effects on men, including reducing the incidence of prostate cancer.