Vegetables differ in their nutrients as well as their content due to different edible parts, shades of color, differences in growing periods, and different parts of the same vegetable. Vegetables can be categorized into three main types: stem and leaf, tuberous root and fruit, in addition to flower and melon vegetables.
The stem and leaf type vegetables are rape, leek, cabbage, spinach, etc., generally rich in vitamin C and carotene. Spinach contains iron, but also contains a lot of oxalic acid, which can prevent the absorption of calcium and iron in food, so before cooking spinach, it should be blanched in boiling water, which can remove some of the oxalic acid, and spinach is best not to eat too much at a time to avoid diarrhea.
The root vegetables are radish, carrot, taro, potato, sweet potato and so on. Radish contains a lot of vitamin C, carrots contain a lot of carotene, sweet potatoes contain both vitamin C and carotene, potatoes, taro contains more starch, high calories, other nutrients less. Tuberous root vegetables have a **** the same characteristics is rich in crude fiber. If the radish, carrot cut into thin slices or thin strips, placed 1 to 2 days later, its crude fiber can increase about 3 times. So radish food to cut now eat, should not be cut and stored.
Fruit vegetables are tomatoes, beans, persimmon peppers, cucumbers, squash, pumpkin and eggplant. This type of vegetables in addition to beans, pumpkin, squash, eggplant, the best raw food, in order to avoid the destruction of vitamins in the cooking process. Tomatoes contain more lycopene and vitamin C. Beans, including lentils, peas and beans, have a higher protein content, more amino acids than grains, and higher content of other things such as calcium, phosphorus, iron, and vitamin B1 than other vegetables. Pumpkin contains a lot of carotene. Chili peppers are rich in carotene and vitamin C.
The same vegetables in different parts of the nutrient content also varies, such as green onion green part than the white part of the onion nutrition content is much higher. Onion white part of vitamin A, vitamin B1 and vitamin C content is less than half of the green part of the onion. The same celery plant, dark green celery leaves than light green stalks, stalks contain more vitamin A and vitamin C. There is also cabbage, its leaves than the stem part of the nutrient content is high.
Vegetables can be divided into four colors: green, reddish-purple, yellow and nearly white. After scientists analyzed the nutrient content of each type of vegetables, they found that dark-colored vegetables have high nutrient content and light-colored ones have low nutrient content. They are listed in the order of green (dark green contains the highest chlorophyll), reddish-purple, yellow and white. Green vegetables include mustard, rape, bok choy, amaranth, spinach and celery. Reddish-purple vegetables include purple kale, which was introduced from Europe, and red cabbage, purple lentils, and eggplant in China. Yellow vegetables include tomatoes, carrots, sweet potatoes, cabbage and so on. Colorless vegetables include winter melon, melon, bamboo shoots, wild rice and cauliflower.
Consumption of green vegetables in order to receive adequate sunlight dark green vegetables is the best. Scientists have found that the same green vegetables, their nutritional value and health benefits often vary with the degree of sunshine. Green vegetables in the vitamins, interferon-inducing agents, etc. are "afraid of heat" weakness, high-temperature cooking can be made to suffer damage, so it is best to eat fresh vegetables, and can be eaten raw is best to eat raw, because the human body needs a "full range" of nutrients, simply eat any kind of vegetable It is impossible to meet this requirement, so only reasonable, clever mix and match, insist on more varieties, more color to ensure balanced nutrition.