Steaming-a good way to preserve nutrition
There are many cooking methods, which can be divided into four categories: one is oil heat transfer, such as frying, frying and frying; One is water heat transfer, such as boiling, stewing and simmering; One is steam heat transfer, such as steaming; The last one is others, such as halogen, mixing and so on. Steaming is a kind of steam heat transfer cooking method, which refers to the process of putting seasoned food raw materials into a vessel, then putting them into a steamer and ripening them by steam. Although China has a 5,000-year-old food culture and various cooking methods, nutritionists prefer steaming cooking methods. Fan Zhihong, an associate professor at the College of Food Science of China Agricultural University, said that it is characterized by keeping the original shape and original flavor of dishes. Compared with frying, frying, frying and other cooking methods, steamed vegetables contain less oil, and can retain various nutritional components of dishes to a great extent, which is more in line with the requirements of healthy eating. This is because when cooking, the boiling point of oil can reach above 300℃, which will destroy nutrients. In contrast, the boiling point of water in steamed vegetables is only 100℃, which can preserve more nutrients. Studies have shown that the content of polyphenols in steamed vegetables, such as quercetin, is significantly higher than that in other cooking methods. At the same time, the steamed food is relatively softer and worse, which is more conducive to digestion and more suitable for people with poor digestive system.
In addition, Wang Xufeng, a national second-class nutritionist, also pointed out that in the cooking process of steamed vegetables, you don't need to add oil and salt, just add a little salt to the last soup to taste, so for modern people who are always high in oil and salt in their diet, it is more conducive to reducing fat and salt and preventing hypertension and obesity. Wang, a national first-class nutritionist, told reporters that the general saying that "steamed food is more nutritious" does not mean that the nutrition of food has increased, but that in the process of cooking, the loss of food nutrition has been greatly reduced, leaving more nutrition. Therefore, when providing dietary nutrition advice to people who come to consult, they will be advised to eat more steamed food, which is more conducive to nutritional intake.
How to cook steamed vegetables is the healthiest?
If you think that cooking steamed vegetables is just putting water in the pot and putting the vegetables in the pot, it's all wet. Steamed vegetables are healthy, but they also test the basic skills of cooking. How to make steamed vegetables delicious and healthy depends on the freshness of ingredients and the mastery of cooking temperature.
Because the biggest feature of steamed vegetables is to keep the original shape and nutrition of food from being destroyed, and the protein in raw materials is not easy to dissolve in water, and the seasoning is not easy to penetrate into the raw materials, so the food texture should be tender, smooth and juicy. Therefore, steamed vegetables have high requirements for the freshness of food raw materials. If it is a stale vegetable, it will wither after steaming and look disgusting. In addition, beef tendon, a dry and hard thing, is not suitable for steaming.
Steamed vegetables are also extremely important in the control of heat, and steaming until the vegetables are cooked is definitely not enough. According to the different ingredients, the cooking time of steamed vegetables can also be divided into three types: strong steaming, medium steaming and slow steaming. Fast steaming in boiling water is suitable for tender raw materials, such as fish and vegetables, and the time is about 15 minutes; For raw materials that are coarse and old in texture and need to be steamed crispy, they should be steamed with boiling water for a long time, such as crispy duck and steamed pork with flour. Fresh and tender dishes, such as eggs, should be steamed slowly with medium fire and low fire.
In addition, Bian Xiao also reminded netizens that if a large steamer is prepared to steam food in layers when preparing for the New Year's Eve, there are two points to pay special attention to: First, the dishes with the same steaming method should be steamed together, and the dishes that should be steamed with a large fire and those that should be steamed slowly with a small fire should not be steamed together, which will destroy the prototype of the food and have certain discounts on nutrition and taste; Second, pay attention to layered placement. Dishes with less soup are placed on top, dishes with more soup are placed below, light-colored dishes are placed above, dark dishes are placed below, dishes that are not easy to cook are placed above, and dishes that are easy to cook are placed below.
Make the steamed vegetables more nutritious.
We are in an era of pursuing diversification, and the nutritional value of steamed vegetables is naturally not satisfied with maintaining food nutrition, but pursuing "extra points" in nutrition. Nutritionists in Wang Xufeng believe that the raw materials of steamed vegetables are very extensive, and China's Millennium food culture is known as "no steamed vegetables". For example, he said that there are basically no vegetables that can't be steamed in Henan, and when cooking steamed vegetables, a variety of vegetables are often used as raw materials. Steaming potatoes, celery, carrots, eggplant, lotus root, chrysanthemum and even wild vegetables together not only makes the steamed vegetables colorful, but also fully embodies the idea of diversified diet. In addition, he also believes that we don't have to stick to wheat flour for the flour with steamed vegetables. Corn flour, millet flour and various kinds of miscellaneous bean flour are all good choices, which can help us supplement coarse grains and increase dietary fiber nutrition.
References:
Steamed vegetables can best preserve nutrition.
Steamed vegetables: the most nutritious way to eat (Author: Wang Xufeng)
Cooking _ Baidu encyclopedia