The loss rate of vitamin C was as high as 65% when Chinese cabbage was scalded in 100 ℃ water for 2 minutes, and almost all of vitamin C was lost when blanched for more than 10 minutes. Therefore, proper methods should be adopted to reduce the loss of nutrients.
How to blanch vegetables? 4 skills of blanching vegetables
Add the right amount of vegetables at a time. If there are many dishes, it is suggested to do it in several times to avoid lowering the water temperature. Blanching time should be short to avoid excessive loss of nutrition.
2. When blanching green leafy vegetables, you should not only add salt, but also oil
This can not only prevent the oxidase from destroying chlorophyll, but also keep the bright color of vegetables. Vegetables such as beans and peas are blanched in cold water and refrigerated for many days without sprouting.
3. Don't cut vegetables before boiling water
Keep the whole shape of vegetables as much as possible to reduce the area of heating and water contact. In the case of more raw materials, it should be fed in batches to ensure that the raw materials are in a higher water temperature.
How to blanch vegetables
4. After blanching, vegetables should be immediately put into cold water to cool down before cooking.
After blanching, the temperature of vegetables is relatively high. After leaving the water, it contacts with oxygen in the air to produce thermal oxygen, which is the continuation of nutrient loss. Therefore, boiled vegetables should be cooled in time. The common method is to use a large amount of cold water or cold air for cooling and heat dissipation, and the latter has less nutrition loss. Which vegetables need blanching to eat? 1. Vegetables containing more oxalic acid
Such as spinach, bamboo shoots, Zizania latifolia, etc., generally speaking, vegetables with a little astringent taste contain more oxalic acid. Excessive intake of oxalic acid will affect the absorption of calcium, zinc and other minerals, and increase the risk of stones. Research shows that vegetables such as spinach and amaranth can remove 40% ~ 70% oxalic acid by boiling water once.
2. Vegetables containing glucosinolates
Mustard vegetables such as kohlrabi contain glucosinolates. Blanched in water and hydrolyzed to produce volatile mustard oil, it tastes better and can promote digestion and absorption.
3. Wild vegetables such as purslane
Wild vegetables may have risks of pesticide residues and pollution by waste water and waste gas. In order to reduce these risks, it is necessary to blanch them before cooking. Blanching wild vegetables such as Portulaca oleracea can completely remove dust and insects and prevent allergy.
How to blanch vegetables
4. Cruciferous vegetables
Such as broccoli, cauliflower and so on after blanching taste better, they contain rich cellulose and are easier to digest.
5. Vegetables containing colchicine
Day lily, also known as day lily, is one of people's favorite dishes. But daylily contains colchicine. If the human body ingests colchicine, it will be oxidized in human tissues to form colchicine. Colchicine is a kind of highly toxic substance, which can poison the gastrointestinal tract and urinary system of human body and seriously threaten the health. If an adult eats 50-100 grams of fresh day lily at a time, it can cause poisoning.
6. Chinese toon
Toona sinensis contains more nitrate and nitrite, which may form carcinogens in vivo. But blanching Toona sinensis with hot water for about 1 minute can remove more than 2 / 3 of nitrite and nitrate. Therefore, it is better to blanch Toona before cooking.
7. Auricularia auricula
Auricularia auricula will absorb a lot of water when soaking, and boiling water is conducive to the discharge of water. Therefore, there will be no frying when frying. What needs to be reminded is that Auricularia auricula is curly, with many "small grooves". After blanching, put the Auricularia into the drain net and drain it, and then knock the drain net several times.