It should be noted that after blanching, the beef contains more heat, and the tissue cells are in a state of expansion and division. If you cook it right away, it is easy to be boiled, and it can also shorten the cooking time and reduce the loss of nutrients. If it is not cooked immediately after blanching, this kind of raw materials will shrink due to the cold surface, resulting in the phenomenon of "rejuvenation", which will eventually lead to unsatisfactory cooking effect.
A pot of water is boiled with different ingredients. First, the ingredients with small smell should be boiled, and then the ingredients with big smell should be boiled. Burn the light color first, then the dark color. In addition, when using spinach, amaranth and other vegetables with high oxalic acid content to make soup or noodles, you should blanch them first, and then put them in when the soup is going out of the pot to avoid too much oxalic acid in the soup.
Extended data:
Bleaching technique
1, add some salt when blanching vegetables.
Can reduce the loss of nutrients in vegetables. From a nutritional point of view, blanching vegetables will increase the loss of water-soluble nutrients. For example, if Chinese cabbage is scalded in boiling water at 100℃ for 2 minutes, the loss rate of vitamins will be as high as 65%. If 1% refined salt is added during blanching, the loss rate of soluble nutrients in vegetables can be slowed down.
It's better to add some alkali when the beans are blanched.
This is because fat keratin and a lot of wax are formed on the surface of beans during their growth. Because these substances cover the chlorophyll contained in the epidermal cells of beans, the green color of beans is not prominent, and the keratin and wax of beans are insoluble in water and only soluble in hot alkaline water. So add a little alkali to the beans, and the beans will appear green.
However, it should be noted that the addition of alkali should not be too much, otherwise it will affect the flavor characteristics and nutritional value of dishes.
If you don't do it immediately after cooking, you should mix some cooked oil.
Great changes have taken place in vegetables after blanching, and the protective wax and tissue cells on the surface of vegetable leaves have been destroyed. If you don't cook it immediately after blanching, it is easy to change color and cause nutrient loss. If blanched vegetables are mixed with cooked vegetable oil, a thin oil film can be formed on the surface of vegetables, which can not only prevent water from evaporating and keep vegetables crisp and tender, but also prevent vegetables from oxidative discoloration and loss of nutrients.
4. The blanching time of brittle raw materials should not be too long.
For example, pork belly, shredded cuttlefish, snail, conch and so on. Because these raw materials are crisp, tender and tough, the fiber texture is delicate and contains a lot of water. If the blanching time is too long, the fiber texture will suddenly shrink, and a lot of water will be discharged, which will make the raw materials stiff and tough, lose the sense of crispness, make it difficult to eat and chew, and have a bad taste. Brittle raw materials should be recoiled after blanching.
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