Most busy modern people eat out most of the time, so leftover food is inevitable. Many people have questions: How should these leftovers be handled? Are all leftovers suitable for taking home?
The science of packing leftovers:
1. Packaged food should be cooled to room temperature before being placed in the refrigerator. This is because when hot food is suddenly placed in a low-temperature environment, the center of the food is prone to spoilage. Moreover, the heat brought by the food will cause water vapor to condense, promoting the growth of mold, which can lead to the spoilage of all food in the refrigerator.
2. Packaged food must be reheated. Food stored in the refrigerator must be reheated after being taken out. This is because the temperature of the refrigerator can only inhibit the growth of bacteria, not kill them completely. If you do not heat the food before eating it, it can cause discomfort after consumption, such as dysentery or diarrhea.
3. The storage time for leftovers should not be too long. Leftovers should ideally be eaten at the next meal, for example, leftovers from breakfast for lunch, and leftovers from lunch for dinner. It is best to finish them within 5-6 hours. This is because, under normal circumstances, certain bacteria, viruses, and parasites can be killed within minutes by heating to 100°C. However, if food is stored for too long, bacteria in the food will release chemical toxins, which cannot be neutralized by heating.
4. Vegetarian dishes are not suitable for taking home. In the process of making vegetarian dishes, salt is generally used in smaller amounts. When cooked vegetarian dishes are left in a relatively warm environment for a long time, bacteria in the food will multiply in large numbers. Under the action of bacteria, nitrates will be reduced to nitrites. Nitrites can easily react with amines in nature to form nitrosamines, which are potent carcinogens. If we consume leftover vegetables for a long time, it is detrimental to our health. For example, the risk of developing stomach cancer is higher for people who regularly pickled foods like salted vegetables.
Things to note when reheating leftovers
Fish: Heat for about four to five minutes.
Bacteria in processed fish dishes multiply easily. The E. coli on the surface can double in number every 8 minutes at a temperature of around 20°C, and within five to six hours, one bacterium can become a hundred million. Such a quantity is enough to cause stomach discomfort. Therefore, packed fish must be heated for four to five minutes. However, if heated for too long, the high-quality protein, fish oil, and rich vitamins in the fish that are beneficial to the human nervous system will lose their nutritional value.Meat: Add some vinegar when reheating.
When reheating meat and animal products, it is best to add some vinegar. This is because these foods contain relatively rich minerals. When heated, these minerals will be lost along with the moisture. Therefore, adding some vinegar during reheating will cause these substances to combine with acetic acid to form calcium acetate, which not only increases its nutritional value but also facilitates the body's absorption and utilization.Seafood: Add seasonings when reheating.
When reheating shellfish and seafood, it is best to add some wine, green onions, ginger, and other seasonings. This not only enhances the flavor but also has a certain bactericidal effect, killing the latent *Vibrio parahaemolyticus* and preventing stomach discomfort. Ginger, in traditional Chinese medicine, has the effect of sterilizing and detoxifying (especially from the toxins of fish, shrimp, and crab).Starchy foods: Finish within 4 hours.
Starchy foods that are taken home should be finished within 4 hours because they are easily parasitized by *Staphylococcus aureus*. The toxins produced by this type of bacteria are not broken down by high-temperature heating, so the problem of spoilage cannot be solved. Therefore, if everyone has not finished the food in a short time, do not eat it anymore, even if it does not appear spoiled on the outside.