Hua En healthy life
When it comes to vegetarian dishes, you can't help but mention tofu. Tofu plays an important role in China's food culture, especially vegetarian culture. This is because tofu originated in China, which is not only nutritious and easy to digest, but also white as jade, soft and tender. It can be used as both a main ingredient and a side dish. The dishes produced are rich in variety and delicious, and are deeply loved by Chinese people.
What's the difference between three kinds of tofu?
The types of tofu in China are mainly divided into north tofu, south tofu and lactone tofu. What's the difference in nutritional value between these kinds of tofu?
Northern Tofu-Tight Tofu
North tofu, also known as old tofu, is made of brine as coagulant, which is characterized by high hardness, strong toughness, water content of about 85% and tough and rough texture.
Southern Tofu-Tender Tofu
South tofu, also known as tender tofu, is made of gypsum as coagulant. It is characterized by tender and smooth texture, elasticity, water content of about 90% and soft texture, and is often called "tender tofu".
Lactone tofu
As for the soft lactone tofu on the market, it is actually made of a new coagulant-gluconolactone. This kind of tofu has better water retention and smoother taste.
Nutritional value of these three kinds of tofu
There are certain differences.
Source: China Food Composition Table (2009) published by Peking University Medical Press.
Compared with South Tofu, protein and calcium content are higher because of its less water content. Lactone tofu has high water content and low nutrients.
Tofu is made by grinding, boiling and solidifying soybeans, but the difference between old tofu and tender tofu lies in the different coagulants used. Old tofu is also called north tofu, the coagulant is brine (mainly calcium chloride or magnesium chloride), the tender tofu is also called south tofu, and the coagulant is gypsum (mainly calcium sulfate).
From the point of view of calcium supplementation, there is no difference between eating old tofu and tender tofu, and the effect of calcium supplementation is very good.
Dietary Guidelines for China Residents suggest that 20 ~ 25g of bean products corresponding to soybeans should be consumed every day. 25 grams of soybeans is equivalent to 77 grams of old tofu or 150 grams of tender tofu. A box of 300 grams of tofu, whether cold, stir-fried or made into tofu soup, is enough to meet the recommended intake of bean products for a family of three, and can also supplement calcium.
In terms of potassium content, the potassium content of tender tofu is 1.45 times that of old tofu. Studies have shown that potassium supplementation can lower blood pressure to a certain extent, so patients with hypertension are recommended to eat tender tofu.
The content of zinc and selenium in old tofu is about twice that of tender tofu, and zinc and selenium are related to human immunity. The weather is getting cold, the immunity is low, and it is easy to get sick. Might as well eat more old tofu to contribute to enhancing immunity.
Bottom line: Eating lactone tofu is far worse than eating traditional north-south tofu. Especially northern tofu, the nutritional value is more than twice as high as lactone tofu.
Spinach and tofu cannot be eaten together.
Onions and tofu can't be eaten together.
Spinach tofu soup and shallots mixed with tofu can be safely eaten, and there is no problem of tofu mixed with spinach or shallots. However, it is best to blanch spinach with boiling water before putting it into tofu soup, because spinach contains oxalic acid, which will affect the absorption of calcium in tofu.
Don't buy two kinds of tofu no matter how cheap it is.
The first type: sticky to the touch.
High-quality tofu blocks should be complete, moderate in hardness and elasticity, very delicate in texture and free from impurities. The structure of broken tofu will become loose and rough, inelastic, and the surface will be a little silky and even sticky. Even if you wash it with water, it will still touch your hand. Don't buy such tofu.
The second type: sour.
Fresh tofu will have a unique faint tofu fragrance. If it goes bad, it will be sour and even rancid. Especially when it is getting hotter and hotter, the shelf life of tofu is actually very short. Don't buy tofu with sour taste.
Tofu is good, but don't be greedy!
Although tofu has high nutritional value, eating too much will also cause some unnecessary problems, such as the following:
1. Causes indigestion: Tofu is rich in protein. Eating too much at a time will not only hinder the absorption of iron, but also cause symptoms such as bloating and diarrhea.
2. Increase the burden on the kidneys: Eating a lot of tofu will lead to excessive intake of plant protein, which will increase the burden on the kidneys and is not conducive to health.
3. Gout patients should eat less: tofu contains more purines, and those with abnormal purine metabolism and high blood uric acid concentration should be used with caution.
Finally, I would like to remind you that the weather is getting hotter and hotter after the long summer, and tofu is easy to deteriorate. When buying tofu, it is best to buy as much as you eat. If you can't finish eating, you can put the rest in the freezer to make frozen tofu.