Keeping green after blanching vegetables can be achieved by the following methods:

1. Add two drops of oil to the water when blanching vegetables

This can prevent the oxidase from destroying chlorophyll and keep the vegetables bright. In addition, the blanched vegetables have a high temperature, and when they are taken out of the water, they come into contact with oxygen in the air, resulting in thermal oxidation, which will not only lose nutrients, but also easily change color.

Therefore, the blanched vegetables should be cooled in time, and they can be put into cold boiled water, but they should be taken out immediately. Need to be reminded that if the blanched vegetables are directly used for cooking and frying, you don't need cold water, but you can't put them in the air for a long time. It's best to cook and fry them immediately after taking them out.

2. Stir-fry over high fire

Whether it's blanching or cooking, use strong fire. On the one hand, it can reduce the oxidation loss of nutrients, on the other hand, it can help to kill the oxidase that can destroy chlorophyll and keep green vegetables. In addition, the cooking time should be as short as possible, and the longer the heating time, the more serious the discoloration of vegetables.

3. Don't put vinegar in open cooking

Studies have proved that acetic acid contained in vinegar will destroy the structure of chlorophyll, turn chlorophyll into "pheophytin", lose its original green color, and vegetables will quickly turn yellow-brown. Therefore, the green leafy vegetables should be cooked with little or no vinegar. Don't cover the pot when cooking and frying, so as to avoid the organic acids in vegetables being difficult to volatilize, forming an acidic environment and turning chlorophyll into "pheophytin".

4. Put the salt later

Salt has a strong dehydration effect. When frying vegetables, the salt is put too early. When the salt and vegetables are stir-fried, the osmotic pressure of the vegetables in the pot will increase, and the dehydrated vegetables will make the fried vegetables look "dry", while putting salt before cooking will make the vegetables crisp and delicious.

Extended information

Methods to reduce nutrient loss when vegetables are blanched

Boiling water with plenty of water and blanching for a short time can reduce the heat loss of nutrients. Because there is oxidase in vegetable cells, it can accelerate the oxidation of vitamin C, especially at the water temperature of 6℃ ~ 8℃. In boiling water, oxidase is unstable to heat and quickly loses its activity. At the same time, boiling water contains almost no oxygen, thus reducing the loss of vitamin C caused by thermal oxidation.

adding 1% salt to the blanching water can make the vegetables in the physiological salt solution, which can slow down the diffusion of soluble nutrients in vegetables into the water. Keep the vegetables intact as much as possible before blanching, so as to reduce the heating and water contact area.

when there are many raw materials, the raw materials should be fed in batches to ensure that the raw materials are at a higher water temperature. After blanching, the temperature of vegetables is relatively high, and it comes into contact with oxygen in the air after leaving water to produce thermal oxygen, which is the continuation of nutrient loss. Therefore, vegetables after blanching should be cooled in time.