Blanching, as the name suggests, is one of the commonly used cooking methods in the home by putting the ingredients in hot water for a short and urgent time before cooking. Some people are accustomed to blanching before cooking, while some people don't like this cumbersome step, thinking that not only the nutrition will be lost after blanching vegetables, but also the taste is not good, it is better to fry directly in the pot, and save trouble. As everyone knows, some vegetables are likely to poison people if they are not blanched and eaten, and even cause death in serious cases, especially the following four types of vegetables.
1. Vegetables with high oxalic acid
Such vegetables include spinach, amaranth, purslane, fresh bamboo shoots, etc. These vegetables are rich in oxalic acid, and after oxalic acid enters the body, it will not only affect the absorption of calcium in the body, stimulate the gastrointestinal mucosa, cause abdominal pain, diarrhea and other symptoms, but also easily form stones with calcium in the urethra. Studies have shown that discarding vegetable soup after blanching can reduce oxalic acid by 30%-87%. Therefore, it is recommended to blanch these vegetables in boiling water at 100°C for 5-10 seconds before eating, and cook them immediately after removing them without affecting the taste.
2. Vegetables that are prone to nitrite
A typical vegetable is toon. Freshly picked toons have a low nitrite content, but if they are left at room temperature for 3 days, their nitrite content will increase dramatically. When nitrite enters the body, it can interact with amines in the body to form nitrosamines, which are well-defined carcinogens that can seriously harm health. Since nitrite is soluble in water, more than 70% of nitrate and nitrite can be removed by blanching it in boiling water. Therefore, remember to blanch the toon for 30 seconds before eating.
3. Vegetables that contain toxins
The first is leguminous vegetables, such as kidney beans, lentils, long beans, etc., these vegetables contain saponin and phytohemagglutinin, if not cooked and burned thoroughly, it is easy to cause nausea, vomiting, numbness of limbs and other food poisoning symptoms after entering the human body. However, this ingredient is afraid of heat, and heating it at 100 °C for more than 5 minutes to make it lose its original green color, or blanching it before eating, can make this toxic into a splitting solution to avoid poisoning.
The second is fresh daylily, fresh daylily contains a substance called colchicine, which will be oxidized into colchicine in the body, which is a highly toxic substance, adults will eat 0.1~0.2 mg colchicine at a time will cause acute poisoning, resulting in nausea, vomiting and other symptoms, which can seriously cause death. Therefore, it is recommended to blanch fresh daylily in boiling water for 5 minutes before eating, and then stir-fry and eat.
4. Vegetables that are not easy to clean
For example, broccoli, cauliflower, etc. These vegetables are not easy to wash and cannot be peeled, and there are likely to be pesticide residues on the surface of the vegetables, so blanching them in boiling water can better remove pesticide residues. It is recommended to blanch in boiling water for 1-2 minutes before cooking, not for too long.
Does blanching affect the taste and nutrition of vegetables?
Many people don't like blanching before eating because they are worried that it will affect the taste and nutrition of vegetables. In fact, vegetables, especially green leafy vegetables, do lose some vitamins and minerals when blanching, but if you master the skills of blanching and preservation, you can retain the nutrients and taste to the greatest extent, so you don't have to worry too much.
1. Generally, when blanching, choose a pot under boiling water, not a pot under cold water, so as to maintain the nutrition and taste of vegetables to the greatest extent.
2. Leaf and root vegetables should be blanched with boiling water at 100 °C as much as possible, and the blanching time should not be too long, keep it within 3 seconds, otherwise it will easily lead to serious loss of chlorophyll, darken the color, and increase vitamin C oxidation. In addition, it is best to cook immediately after fishing, if you do not cook for the time being, you can put it in the refrigerator after cold water, and you can also add vegetable oil to the vegetables to help effectively slow down the evaporation of vegetable water, and at the same time can prevent vegetables from being oxidized, in order to prevent further loss of nutrients, which can be described as killing two birds with one stone.
3. It is worth noting that if a pot of water blanches different ingredients, the small smell should be blanched first, and then the big smell; Blanch the light ones first, then the dark ones. In addition, when making soup or noodles with vegetables with high oxalacid such as spinach and amaranth, you should blanch them first and put them in when the soup is about to come out of the pot to avoid too much oxalic acid in the soup.