People from the North: Yes, don't you see tea eggs sold everywhere!
People from the South: No, especially for men, because it can cause hernia/scrotal swelling.
Scientists: Not necessarily! Because if the egg is not fully cooked, the uncooked yolk, if eaten overnight, can easily breed bacteria if improperly stored, which can be harmful to health, such as causing gastrointestinal discomfort, bloating, etc.
However, if the egg is fully cooked and properly sealed and stored at a low temperature (like a refrigerator), it is generally fine to keep for 48 hours. From the scientist's tip, we can know: whether overnight eggs can be eaten depends not just on whether they are reheated, but on whether they were fully cooked the first time they were boiled. Only after being fully cooked the first time can they be reheated and eaten the next day without a problem. Tea eggs are a good example of this. Many people may not know that tea eggs are boiled twice: the first time to cook them through, and the second time after cracking the shells and adding tea and other ingredients to simmer again. So tea eggs are definitely cooked. Now, some people like to eat half-cooked eggs (with a runny yolk); those eggs cannot be eaten overnight, even if they are reheated the second time.
2. Overnight tea should not be drunk!
Because it has been left for too long, most of the vitamins in overnight tea are lost, and the proteins, sugars, etc., in the tea become nutrients for bacteria and mold to grow, so people generally believe that overnight tea should not be drunk.
3. Even overnight boiled water should not be drunk?
Boiling tap water for 3-5 minutes minimizes the content of harmful substances like nitrites and chlorides, making it most suitable for drinking. Drink less overnight boiled water: Nitrites can form carcinogenic nitrosamines in the body. Experts have found that the nitrite content in boiled water is higher than in raw water. Moreover, the nitrite content increases significantly in water that has been boiled repeatedly for too long or for more than 24 hours. After being left for 24 hours, the nitrite content in boiled water is 1.3 times higher than when it was just boiled. Chinese people have a habit of drinking boiled water. It is best to boil and drink it fresh or only drink the boiled water from the same day, and avoid water that has been boiled for too long.
4. Can overnight tremella (wood ear fungus) be eaten?
Tremella soup is a high-nutritional health food, but after being left overnight, its nutritional value decreases and harmful substances are produced. This is because both indoor-cultivated and log-cultivated tremella contain a relatively high amount of nitrates. After being cooked and left for a long time, under the action of bacterial decomposition, the nitrates are reduced to nitrites. When a person drinks this soup, nitrites naturally enter the bloodstream. The red blood cells in the blood contain hemoglobin, which can carry large amounts of oxygen for the body's needs. However, nitrites have the opposite effect, oxidizing the body's normal hemoglobin into methemoglobin, which loses its ability to carry oxygen, causing a lack of normal hematopoietic function in the body!
5. Do not eat overnight leafy green vegetables!
Because some leafy green vegetables contain a relatively high amount of nitrates, if cooked and left for too long, under the action of bacterial decomposition, the nitrates will be reduced to nitrites, which are carcinogenic and cannot be removed by reheating. Healthy way to eat: Leafy stem vegetables usually have the highest nitrate content, followed by root and stem vegetables and flower vegetables like cauliflower, with gourd vegetables being lower. Therefore, if you buy different types of vegetables at the same time, you should eat the leafy stem ones first, such as Chinese cabbage, spinach, etc. If you plan to cook extra food to reheat the next day, you should try to make fewer leafy stem vegetables and choose gourd vegetables instead.
6. What to do with overnight soup?
Put leftover soup in the refrigerator and bring it to a boil again the next day to drink. Is this overnight soup good for your body? Healthy way to eat: The best way to store soup is not to add seasonings like salt to the base. After cooking the soup, use a clean spoon to serve the portion for the day. For the leftover soup, it is best to store it in a clay pot in the refrigerator. Because when leftover soup is kept in aluminum or stainless steel pots for a long time, chemical reactions are likely to occur. It should be stored in glass or ceramic containers.
7. Seafood should not be eaten overnight!
Overnight foods that should not be eaten include fish, seafood, leafy green vegetables, and cold dishes. Fish and seafood can easily produce protein degradation products overnight, which can damage liver and kidney function. Leafy green vegetables contain varying amounts of nitrates. If overcooked or left for too long, not only will the vegetables turn yellow and change in flavor, but the nitrates will also be reduced by bacteria into toxic nitrites, which have carcinogenic effects. Cold dishes are often more contaminated during preparation, so even after refrigeration, they are very likely to have spoiled overnight and should be made and eaten fresh.