1, fry quickly

Cooking is a heating method based on oil heat transfer, supplemented by direct heat transfer in the pot. Its cooking speed is faster and the loss of soluble water is less. The loss of water-soluble vitamins in ingredients is usually less than that in stewing, but putting more oil will greatly increase the fat content of dishes and cause the loss of carotenoids.

Step 2 bake

The oven temperature can be controlled below 200 degrees Celsius. If the food is wrapped with tin foil, the local temperature can be kept at about 100 degrees Celsius, so that the food can be heated evenly, the nutrients can be maintained well, and less harmful substances are produced. It is also a recommended cooking method.

However, it is not recommended to roast food (such as kebabs) with open flame carbon, because the temperature can't be controlled, and local heating over 200 degrees Celsius will produce heterocyclic amines and polycyclic aromatic hydrocarbons carcinogens, and the surface of baked food will be contaminated with a large number of smoke particles containing carcinogens. Barbecue smoke itself will produce a large number of carcinogens such as PM2.5 and benzopyrene attached to the smoke, which is very unfavorable to lung health.

3. Microwave

Foods rich in water, such as porridge, noodles, milk, vegetables, etc. And is more suitable for microwave heating. Microwave heating efficiency is high, and the cooking time is shortened accordingly, so the loss of vitamin C, flavonoids and chlorophyll is small, there is almost no problem of water loss, and too much oil will not be added to the dish. The main disadvantage of microwave cooking is that the aroma is slightly insufficient and there is no effect of external coke and internal tenderness.

4. High pressure cooking

Compared with normal pressure cooking, pressure cooker cooking is not only simple and fast, but also because the pot body is closed, it is no longer in contact with the outside air after exhausting or pressurizing, which is conducive to preserving the antioxidant active ingredients in the ingredients and has a low degree of fat oxidation. For the ingredients that need to be stewed for a long time in atmospheric cooking, such as beef, miscellaneous grains, beans, etc., the vitamin loss is equivalent or slightly less.

Step 5 steam vegetables

Steaming vegetables is almost the most comprehensive cooking method to retain nutrition. Steamed vegetables have neither the loss of nutrients dissolved in soup when cooking or cooking, nor the problem of too high temperature when cooking. The heating temperature does not exceed 100℃, and the thermal decomposition loss is small, the oxidation loss is small, there is no oil fume, and too much oil will not be introduced.

Step 6 boil

Boiling includes boiling, stewing and scalding. Water is used to transfer heat to food. The boiling temperature is 100℃. Although it will not produce harmful substances, there will be a lot of soluble substances dissolved in water during boiling, such as vitamin C, vitamin B2, folic acid and so on. If you don't drink soup, the loss of these nutrients will be even greater.

Step 7 fry

Water frying is often used to make fried dumplings, pot stickers and other foods. The basic principle is to put a small amount of oil to heat the raw materials, then put water on the lid and steam the raw materials. After the water evaporates, leave a little oil at the bottom of the pot, and fry the bottom of the raw materials until they are crisp, so as to achieve the effect of crispy top and tender inside.

This method is very suitable for cooking quick-frozen semi-finished products with a little oil on the surface, such as egg cakes, fish sticks and popcorn. Compared with frying method, the finished product has less nutritional loss and lower fat content.

However, fried foods are not only high in oil content and calories, but also seriously damaged by vitamins and antioxidants, and high oil temperature will inevitably produce carcinogens. Repeated use of frying oil will produce harmful substances including trans fatty acids and various oxidative polymerization products, which is extremely harmful to health. Smoke contains carcinogens, and inhalation into the lungs will increase the risk of lung cancer.

Extended data

Matters needing attention in cooking

1, vegetables should be washed before cutting, then fried before eating.

Because vitamin C is easily soluble in water and its chemical properties are unstable, it is best not to chop it up before washing it, let alone soak it for a long time.

Don't squeeze out the vegetable juice.

Vegetable juice is rich in vitamin C, enzymes and other nutrients, and generally should not be squeezed out. If you need to squeeze out vegetable juice during special cooking, make full use of it and don't waste it.

3. Use some vinegar appropriately

If you can put a little vinegar in cooking, it will not only taste delicious, but also strengthen the protection of vitamin C, because vitamin C is not easy to decompose in acidic environment.

4. It is not advisable to add alkali.

Adding some alkali when cooking beans and vegetables can soften the food, but it will destroy and invalidate a lot of vitamin C and reduce the nutrition of vegetables, so it is best not to use it.

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