The truth | Are leftovers poisonous?

The truth | Are leftovers poisonous? I don't know since when, "leftovers" have often been associated with the word "cause...

I don't know since when, "leftovers" have often been associated with the word "cancer". For a time, questions about leftovers have been widely circulated in the circle of friends. Is this kind of overnight food really poisonous and can cause cancer? Today, the editor will explain to you how to eat overnight Food safety issues.

First, there are two major safety issues with overnight food. One is the proliferation of microorganisms, which can cause food deterioration; the other is the increase in nitrite, which can cause food poisoning and cause cancer.

How to judge whether leftovers are safe? Even if the above is overnight, there are different opinions that some food in summer may go bad after being stored at room temperature for 4 hours. Therefore, whether leftovers are safe does not depend on whether they are left overnight, nor on the length of storage time, but on whether harmful substances are produced or spoiled during the storage process.

Leftovers will deteriorate if leftovers are stored for a long time. The production of nitrite is the most concerning issue for everyone. In fact, nitrite is not a scourge. The enzymes contained in vegetables and the enzymes produced by bacteria can convert the nitrate in vegetables into nitrite. Only when excessive nitrite enters the human body, under the action of gastric acid, will combine with the biogenic amines in the stomach to form "nitrosamines". Nitrosamines are the exact carcinogens. Pay attention to one word, excessive. Only excessive nitrite is a problem. (The national regulation is not to exceed 30~70 mg/kg)

Everyone is reluctant to leave leftovers and dare not eat them (especially for people of the grandparents generation). In fact, leftovers are not absolutely inedible. As long as they are properly preserved and cooked properly, they can still be eaten.

The most scientific way to handle vegetables

The fourth point of the "Five Key Points of Food Safety" proposed by the World Health Organization, "Maintaining safe food temperatures", recommends that cooked food should not be stored at room temperature for more than 2 hours, should be refrigerated in time (preferably below 5℃), and should not be kept in the refrigerator for more than 3 days. Leftovers should not be reheated more than once.

1. Allow hot food to cool before placing it in the refrigerator

Hot food suddenly enters a low-temperature environment. The heat of the food will cause water vapor to condense and promote the growth of mold, thus causing the food in the refrigerator to become moldy.

After it cools down, put it in the refrigerator in time. Even in winter, don't leave it outside for a long time, because the refrigerator has a certain antibacterial effect.

2. Store different leftovers separately

to avoid bacterial cross-contamination. It also needs to be stored in a clean container, such as a fresh-keeping box, a fresh-keeping bag, or a layer of plastic wrap on the dishes.

3. The storage time should not be too long

It is best to eat it within 5~6 hours. However, if the food is stored for too long and nitrite and aflatoxin are produced, heating will not be effective.

4. Reheat the food before eating

In addition to proper storage, reheating is also the key to ensuring health. Store leftovers in the refrigerator. Before eating, be sure to return the dish to a high temperature, heat the entire dish to 100°C, and keep it boiling for more than 3 minutes. Because low temperature can only inhibit bacterial reproduction but cannot completely kill bacteria.

5. Clean the refrigerator regularly

Many families' refrigerators are not cleaned regularly, and various types of bacteria (especially E. coli) will breed in the moist and cold environment. If you take out refrigerated food and eat it immediately, bacteria will invade the gastrointestinal tract and cause "refrigerator gastroenteritis". Therefore, the refrigerator needs a general cleaning every three months or so.