Although people often put the freshest and healthiest food into the shopping basket, many people throw away the nutrition we really need when cooking. To this end, American nutritionists and food safety experts have listed eight common mistakes made by smart housewives in cooking. Looking at their dietary advice will make the food on your table healthier.

Error 1:

Buy too many vegetables at once. Dr. Gerry Brewster, a health consultant at North Westchester Hospital in San Quisco, new york, said: "From the moment of picking, the vitamins and minerals in fruits and vegetables began to decrease." In other words, the longer the vegetables you buy are stored, the less nutrients they have. It was found that half of folic acid and 40% of lutein in spinach would be naturally lost if stored in the refrigerator for about a week. Dr. Gerry suggested that you should not buy too much food at a time, and it is most appropriate to buy it three times a week.

Mistake 2:

Store food in a transparent container. If the milk you are drinking now is still packed in transparent plastic bags, I suggest you consider changing it to milk packed in cartons. Researchers at Ghent University in Belgium pointed out that riboflavin rich in milk is easily lost in the sun. To this end, American food scientists suggest that milk and grains should be avoided in transparent containers as far as possible, so as to preserve nutrition.

Mistake 3:

Fried garlic. Dr. John Milner, head of the Nutrition Research Group of the American Association for Cancer Research, said: "Crush garlic, slice it and leave it for at least 10 minutes before cooking. Crushing garlic will trigger a chemical reaction of an enzyme and release a compound that can fight cancer; Put 10 minutes before cooking to give this compound enough time to fully form. "

Mistake 4:

Use less seasoning. Without increasing edible oil and salt, using more plant seasonings and spices can not only play the role of seasoning, but also prevent people from food poisoning. Researchers from the University of Hong Kong conducted antibacterial tests on 20 common spices (including Escherichia coli, Staphylococcus and Salmonella). ), and found that clove and cinnamon have strong antibacterial ability. According to another study published in the American Journal of Agricultural and Food Chemistry, rosemary, thyme, nutmeg and laurel leaves are also rich in antioxidants. Add half a spoonful of seasoning every time, which is safe and healthy.

Error 5:

Peel the fruit a few more layers. The research published in the American Journal of Nutrition Research found that the antioxidant activity in the peel of most fruits is 2-27 times higher than that in the pulp of fruits. Nutritionists suggest that peeling potatoes and carrots gently is enough. If some fruits and vegetables must be peeled before they can be imported, try to remove a thin layer of skin.

Error 6:

Slowly stew vitamins and minerals. Generally speaking, cooking is a simple cooking method, which does not need to refuel or lose nutrition. But in fact, this cooking method will lead to the loss of 90% nutrients at most. Dr Karen Collins, nutrition consultant of American Cancer Research Association, said, "Potassium and soluble vitamins will overflow when mixed with water." Adding a small amount of water for stewing, slow cooking or frying in microwave oven can reduce the loss of nutrients. Cooking is suitable for dark green or orange vegetables.

Error 7:

Do you want to wash some food? When we eat plums or strawberries, we always wash them first. But when eating bananas, oranges or mangoes, few people wash them with water. It sounds strange to clean peeled food, but when you cut the fruit, harmful bacteria left on the surface of the food may get on your hands and even invade the inside of the fruit. Wash your hands with soap or warm water for at least 20 seconds before holding chopped fruit, which can effectively prevent the spread of bacteria.

Error 8:

Improper food collocation reduces nutrition by half. Many people think of iron supplementation when they feel weak and listless all day. Pay attention to the scientific collocation between different foods when supplementing iron. When eating beans and green leaves, eating some foods rich in vitamin C, such as peppers, potatoes, strawberries, etc., will improve the iron absorption rate. On the contrary, drinking tea or coffee with meals will inhibit the body's absorption of iron, up to 60%. If you haven't finished your meal thoroughly, you'd better not drink tea and coffee.

How to cook and eat is beneficial to the health of the elderly.

1, Pay attention to food hygiene: You must pay attention to food hygiene at ordinary times, and do not eat unclean food or drink unclean water. Wash your hands before and after meals, and it is best to use tableware or public chopsticks alone when eating.

2, to chew slowly: the elderly have bad teeth, poor chewing ability, coupled with the decline in gastrointestinal digestion, should chew slowly to reduce the burden on the stomach.

3, often eat vegetables and coarse grains: often eat some fiber-rich vegetables and coarse grains, can increase gastrointestinal peristalsis, prevent constipation, help maintain gastrointestinal health, reduce the occurrence of intestinal cancer.

4, eating should be regular, and it should be quantified regularly: every meal should be quantified regularly, which can form a conditioned reflex, which is conducive to the secretion of digestive glands and the digestion and absorption of food.

5, eat less fried, fried foods: Because these foods are difficult to digest, eating too much will naturally increase the burden on the gastrointestinal tract and even indigestion.

6, eat less cold and irritating food: cold and irritating food has a strong stimulating effect on the digestive tract mucosa, which is easy to cause diarrhea or digestive tract inflammation, or aggravate the original digestive tract diseases, and should be eaten as little as possible.

7. Eat less smoked and pickled foods: These foods are high in salt and contain some substances that may cause cancer. It is not advisable to eat more or often.

8. Drink less and quit smoking: Alcohol and tobacco will damage the digestive tract mucosa and reduce digestion? Extremely detrimental to health.

9. Eat less high-fat and high-protein foods: excessive intake of fat and protein can easily lead to indigestion.

Zero loss is healthy cooking.

Choosing ingredients is the key to healthy dishes.

Jiao, the national judge of catering industry in China, pointed out that it is healthier to eat different things in different seasons, such as eating some cool food in summer, such as ducks and pigeons. Eat hot food such as roe deer, venison and dog meat in winter. However, Jiao also said that out-of-season food is not completely inedible, as long as it is scientifically matched and eaten in moderation. If you want to eat mutton in summer, you should cooperate with cold melon, wax gourd and other foods. As the saying goes, following the standard of "cool is hot, hot is cool", we must pay attention to balance.

As for healthy dishes, Jan Chen Rui, a senior technician in charge of cooking at the International Cuisine Federation, said that healthy dishes should be a process of scientifically and reasonably processing cooked food on the basis of ensuring food safety and realizing human tissue renewal and material metabolism. If it is not safe, it is a failure.

Diet structure is also very important for the health of dishes. Zhan said that modern people's diet structure is very unreasonable, overeating and high-calorie diet are blind, and unscientific food choices only satisfy their appetite, color and fragrance.

Zhan believes that healthy food is organic and pollution-free from the perspective of material selection. The second is to buy food that has passed the inspection and has been designated for sale by the relevant state administrative departments, and to prevent unlicensed vendors from selling food. The third is reasonable handling. The premise of reasonable processing is reasonable cooking. The size of raw materials will lead to the loss of nutrients in food, and the number of cleaning will also lead to the loss of high nutrients. There are many water-soluble nutrients and less fat loss, so there are micro and macro water-soluble, such as B group and minerals. In cooking, unscientific cooking methods, such as baking and smoking. Although the diet has developed to this day, when cooking food, it is only to achieve appetite. With the renewal of ideas, from the perspective of food nutrition and health, the first thing is to select materials, process and cook, and finally talk about color, fragrance, shape and nutrition. Taste first, then raise, taste outside, raise inside.

Scientific nutrition ratio is healthy.

Regarding popular spicy dishes, Zhan said that spicy dishes contain capsaicin, which promotes fat burning. Spicy food is more exciting, but from a nutritional point of view, some people are not suitable to eat spicy food, such as oral ulcer, pharyngitis, intestinal diseases and low digestive function of the stomach. Therefore, nutrition is targeted at different groups of people and targeted food selection. Healthy food is based on this, and it is not only taste and feeling that do not need nutrition.

To maintain physical strength, people need to take in different proportions of nutrients, such as heat energy ratio, meat-vegetable ratio, acid-base ratio and so on. Confucius said, "Wide food, delicious food, omnivorous food and nutrition." Therefore, Zhan stressed that healthy dishes should be based on the dietary pagoda formulated by the Nutrition Society of China, such as how many beans, how much oil, how much salt, how many vegetables and how much meat you eat a day. If you blindly consume high-calorie drinks, too much sugar, chocolate, meat and fat will easily lead to acidic constitution, which is not conducive to health. If medicinal materials are involved, the Ministry of Health has new regulations, only 87 kinds of medicinal materials can be eaten, and there are also maximum dosage regulations. The regulations clearly point out that neither ginseng nor Cordyceps sinensis can appear in medicated diet, mainly from the perspective of safety, so be extra cautious when eating.

In addition, Zhan also said that the "China-Peking Man's Favorite Healthy Dishes Selection" jointly organized by our newspaper and China is very meaningful, because people need to get the guidance of healthy dining tables around them through such activities, guide people to understand and break some misunderstandings about diet, and make people's lives healthier. For a long time, people's understanding of healthy food has been biased. Some people think that healthy food is a dish with medicinal ingredients, or a dish that is light and difficult to guarantee its taste. In fact, healthy eating is the advanced stage of Chinese food. In fact, the correct understanding of healthy eating is to replace unhealthy things with healthy ways. For example, braised shark's fin, which used to be chicken oil, is now replaced by carrot juice and pumpkin juice, with the same color and taste, but the protein and cholesterol are greatly reduced, which is also a sign of healthy diet. People constantly replace some famous dishes with people's favorite or plants in life and practice.

Healthy dishes are not insulated from delicious food.

Choosing the right ingredients and mastering scientific cooking methods can make healthy dishes. Jiao said that scientific cooking is to minimize the loss of nutrients in raw materials and remove unnecessary and odorous ingredients, that is, to preserve the good and eliminate the bad, including maintaining a good taste.

Zhan suggested that from the perspective of cooking, the pot should be cooked quickly to reduce the loss of nutrients, and vegetables can be mixed with a little starch to prevent the loss of nutrients and water. Sometimes the food is not delicious, but the juice is delicious. Starch belongs to polysaccharide, which can retain water and prevent loss.

Of course, scientific cooking of healthy dishes does not mean that it has nothing to do with delicious food. Jiao said that no matter what dishes, as long as they are vegetables, they should be based on delicacy. For example, spicy food is not necessarily bad food. Spicy food can speed up blood circulation, dispel dampness and clear heat, but it should be suitable for different regions and vary from time to time. Nowadays, popular health care dishes also pursue diversified tastes, including medicated diet. Medicinal diet is not necessarily a combination of vegetables and medicinal diet. Chefs have a purpose, choose collocation, people choose to eat, and eat scientifically and nutritionally. For example, lily and celery add up to clear away heat, reduce blood fat and increase lung vitality.

Besides, many people think that frying things is unhealthy. Jiao Yao Ming said that, in fact, frying does not necessarily increase oil. For example, the chicken leg of an old chicken has a lot of oil under its skin. If you add something to stir fry, you can stir fry all the oil. When braised pork is oiled, a lot of fat can come out. Frying in oil is not the same as stewing in water directly. Stir-fry a lot of oil first, so you can skim off the oil and not eat it. If stewed directly, protein will go bad and be insoluble in water. This kind of meat is very fat. In addition, people may not eat a lot of oil with oil. Some things can be fried with animal raw materials, so it cannot be said that frying is an unscientific cooking method.

Zhan Chenrui also stressed that the way of cleaning ingredients is also very important. He said that after experiments, washing vegetables for a long time caused about 50% to 60% loss of nutrients, and it should not be too fine when cutting. When you pack jiaozi, you cut vegetables and add salt to kill all the water, which means that the loss of water and nutrition is equivalent to eating the residue in your mouth.

■ Delicious, do it yourself

Experts recommend healthy winter dishes.

The diet is different all year round. People should do the simplest, healthiest and most natural things. Winter should be warm, eat more yang, nourish liver and lungs, and nourish yin.

Braised mutton with crucian carp: Fish and mutton are very fresh. Stew the mutton to a certain temperature and add the scalded crucian carp. At this time, the soup is fresh and has no fishy smell, so there is no need to add any seasoning. In the past, there was a kind of fish biting sheep, that is, the bones of the fish were removed and the mutton stuffing was put on and steamed together.

Roasted venison skewers with vegetable juice: celery is juiced, venison is bled, cut into pieces and soaked in celery juice, then skewered and roasted or fried according to your favorite taste. This kind of thing is suitable for autumn and winter. Venison has the highest energy. Intern reporter Qu Zengping reporter Zhu Ruijuan

What cooking tips are there in life?

There are many tricks in our daily diet and cooking, which can make our food more delicious and solve some small troubles. Below I will share with you a few tips on diet and cooking.

How to cook without spilling? When cooking porridge, drop two drops of sesame oil into the pot. After boiling, cook it slowly with a small fire so that the porridge will not overflow. Or sento good rice, wait until the pot is half open, then put the rice in the pot to prevent the rice soup from overflowing.

How to cook without sprinkling?

When cooking porridge, drop two drops of sesame oil into the pot. After boiling, cook it slowly with a small fire so that the porridge will not overflow. Or sento good rice, wait until the pot is half open, then put the rice in the pot to prevent the rice soup from overflowing. When cooking with a rice cooker, just wash the rice in advance, soak it in proper amount of water for 2-3 hours, and cook it for a while to avoid rice soup overflowing.

Add salt to the dough to prevent caking.

When kneading dough, you often touch the dough and form a small ball. Mixing dough is not only laborious but also very difficult. There is a small coup, that is, when flour is mixed with water, add a little salt and stir together, so that dry noodles are not easy to form balls. It is also very convenient and labor-saving to mix noodles like that, and steamed bread is particularly fragrant.

Qiaopao jellyfish silk

Jellyfish silk is delicious, but it is particularly difficult to wash. It is difficult to remove the astringency of jellyfish silk if it is not washed well, which will affect the taste. There is a small way to remove the astringency of jellyfish silk. Jellyfish silk is brewed with boiling water before washing jellyfish silk, and then jellyfish silk is quickly soaked in cold water for a period of time. The jellyfish silk soaked in this way will not shrink, and it is delicious and refreshing, without astringency.

There are many cooking tips in life. As long as we pay more attention and summarize, we can make our life better and sweeter.

Five six food cooking methods need to be careful.

Many vegetables are the food we must eat every day. Vegetables are the best food to nourish the body. In daily life, many people eat vegetables in the wrong way. Some vegetables and diets are very toxic and may be fatal if they are not cooked, so we must pay attention to the details in life. The following small series introduces you to 7 kinds of foods. If you eat them raw, they will be more poisonous than arsenic! Everyone should keep their eyes open and see clearly.

1, raw soybean milk

Lethal toxin saponin

Cause and mechanism Because raw soybean contains toxic ingredients, if soybean milk is eaten uncooked, it will also cause food poisoning. Especially when soybean milk is heated to about 80℃, the saponin expands and the foam floats up, forming a "false boiling" phenomenon. In fact, the toxic components such as saponin in soybean milk have not been completely destroyed at this time. If you drink this kind of soybean milk, it will cause poisoning, usually after eating 0.5 ~ 1 hour, you will get sick, mainly the symptoms of gastroenteritis.

Detoxification method In order to prevent drinking raw soybean milk poisoning, when cooking soybean milk, it should be heated to 100℃ after "fake cooking". The boiled soybean milk has no foam, and the disappearing foam also shows that toxic components such as saponin are destroyed. If you cook it with low fire for about 10 minutes, you can achieve the goal of safe consumption.

2. Green beans; Beans; green soya bean

Lethal toxin saponin

Fatal mechanism If the green beans are not cooked, the saponin in the beans will strongly stimulate the digestive tract, and the beans contain thrombin, which has a clotting effect. In addition, green beans also contain nitrite and trypsin, which can stimulate the human stomach and cause food poisoning and gastroenteritis.

Detoxification methods In order to prevent kidney bean poisoning, kidney beans must be thoroughly cooked.

3. cassava

Lethal toxin flaxseed picroside

Fatal mechanism Although cassava tuber is rich in starch, all parts of the whole plant, including roots, stems and leaves, contain toxic substances, and fresh tuber is more toxic. The toxic substance contained in cassava is linseed picroside. If you ingest raw or uncooked cassava or drink its soup, it may cause poisoning. The reason is that flaxseed picroside or flaxseed picrosidase produces free hydrocyanic acid after gastric acid hydrolysis, which makes people poisoned.

If a person eats 150 ~ 300 grams of raw cassava, it will cause poisoning and even death.

Detoxification can prevent cassava poisoning by peeling cassava before eating, soaking potato meat with clear water and dissolving cyanosides. Generally, soaking for about 6 days can remove 70% of cyanosides, then heating and cooking before eating.

4. Broad beans

Lethal toxin, lethal glycoside

Fatal mechanism Vicia faba seeds contain nestin glycoside, which can cause acute hemolytic anemia (Vicia faba yellow disease) after human consumption. Eating green broad beans in spring and summer, if cooked improperly, will often cause poisoning. And it usually happens 4 to 24 hours after eating raw broad beans.

Detoxification method In order to prevent broad bean poisoning, it is best not to eat fresh and tender broad beans, and it must be cooked before eating.

5. Hemerocallis

The deadly toxin colchicine

Fatal mechanism day lily, also known as day lily, is one of people's favorite dishes. However, day lily contains colchicine. If the human body ingests colchicine, it will be oxidized in human tissues to produce colchicine. Colchicine is a highly toxic substance, which can poison human gastrointestinal tract and urinary system and seriously threaten health. If an adult eats 50 ~ 100 grams of fresh day lily at a time, it can cause poisoning.

Detoxification method can prevent fresh day lily from poisoning. Fresh day lily can be boiled in boiling water for a while, and then soaked in clear water to remove most of the water-soluble colchicine. You can also cook fresh daylily thoroughly before cooking.

6.shepherd's purse

Lethal toxin nitrite

Fatal mechanism Wild vegetables such as shepherd's purse and grey vegetables all contain a lot of nitrite. If the human body ingests too much nitrite, the normal hemoglobin in the human body can be oxidized to methemoglobin. In addition, nitrite can also prevent oxygenated hemoglobin from releasing oxygen, thus causing tissue hypoxia and poisoning.

Detoxification method must let family members eat fresh vegetables. Cooked vegetables should not be stored for a long time. Pickled vegetables should be pickled for one month before they can be eaten.

Tips: Don't add brown sugar to soy milk when drinking soy milk, don't drink uncooked soy milk, don't eat soy milk on an empty stomach, and don't use soy milk as a drug guide. If you drink soy milk with medicine, the nutrients of soy milk will be destroyed by medicine or have side effects. Be careful!