For every family, leftovers are always unavoidable. However, there is an online article saying that putting leftovers in refrigerators will increase the nitrite content of foods and cause cancer. Then leftovers Will the refrigerator become a 'poison'? How can we cook safely and eat well? The author interviewed Lei Min, the deputy director of the Nutrition Department of the Third Hospital of Hebei Medical University.
'It should be said that the problem of nitrite carcinogenesis does exist, but putting leftovers in the refrigerator is not a 'culprit' for our health. ' Lei Min said that someone had done an experiment if he put a The newly prepared dish was put into the refrigerator without turning. The content of nitrite was only increased from 3mg/kg to 7mg/kg the next day. The value was far lower than the nitrite carcinogenic national standard.
According to experts, nitrates in foods can be converted to nitrites under the action of nitrate reductase. All factors that are conducive to the growth and reproduction of certain reducing bacteria, such as temperature, humidity, pH, etc., can be Promote the reduction of nitrate to nitrite. Normally, the content of nitrate and nitrite in food increases with the storage temperature. Therefore, leftovers are put in the refrigerator, although nitrous acid The salt content will increase, but the total amount is still lower than the storage at room temperature. From the health point of view, the food refrigerator is still a safer choice. In addition, different storage methods will also make the nitrate and nitrite content There are significant differences. In general, the optimal storage option is a refrigerator bag, which is then stored in a refrigerator, stored at room temperature, and bagged at room temperature.
For leftovers, the increased nitrite content is not as horrible as the article said. According to experts, nearly all foods will increase in nitrite content as storage time increases. When the quantity is controlled within the safe range, it will not cause harm to the human body.
How to easily judge whether the nitrite content is beyond the standard? 'For most fruits and vegetables, whether raw or cooked, if the sensory state to maintain a fresh and normal state, its nitrite content is relatively low, if you start to decay Or rancidity, then its nitrite content will increase rapidly.' Lei Min said.
What is the difference between the increased nitrite content and hazards of different foods (eg meat, vegetables, cereals) left in the refrigerator after meals?
'For different foods, different varieties, origins, seasons, freshness, edible parts, growth stages, storage conditions, cooking methods, etc., will make the difference between the nitrate and nitrite content of dishes. ' Lei Min said that under normal circumstances, the content of nitrite in leeks is relatively low, so if it can not eat, it is necessary to adhere to the principle of 'remaining large meat leftovers, no seafood, soy products and cold dishes'.
'Although refrigerators can delay the production of nitrite in leftovers, refrigerators are not a 'treasure chest' and there is a time limit for food storage. ' Lei Min said that with the extension of storage time, leftovers will The bad taste, loss of some nutrients, but also easy to breed bacteria, mold and toxins, accelerate food spoilage, and thus pose a safety hazard to human health.
How can we eat safe and nutritious? Maybe listen to the advice given by the experts.
For dishes that require frying, proper cooking is the key. When processing, you can use water or blisters on the dishes first, so that most of the nitrates and nitrites are lost in the water, and the dishes are thoroughly cooked and cooked before serving.
For salad dishes, it is very important to place the allowance in advance into the refrigerator and put it in the refrigerator. In addition, garlic and vinegar should be added to the seasoning. “This is because of garlic, vinegar and lemon juice, etc. Both can inhibit the growth of bacteria and naturally help control the production of nitrite. ' Lei Min said.
'For leftovers, they should be eaten as much as possible within 24 hours. But if it is really difficult to 'eliminate', we must pay attention to thoroughly heating the dishes thoroughly when eating again. ' Lei Min said that during the heating of leftovers, You can also add fresh garlic, chili, ginger, tomato, vinegar, hawthorn and other natural ingredients, and serve with foods rich in vitamin C, such as tomatoes, kiwifruit, strawberries, prickly pears, grapefruit, etc.; foods rich in vitamin A, Such as the liver, deep red and dark green vegetables and fruits; foods rich in vitamin E, such as nuts, beans, vegetable oil, etc., to block the production of carcinogens.