The word “overnight” seems to carry some kind of debuff, as long as it is overnight, it will produce “toxin” and cause cancer.
But when you open the refrigerator and see yesterday’s leftovers, you start to hesitate: throw it away, which is a pity. If you don’t throw it away, you’re afraid of eating bad.
So, overnight food, eat? Or not? I’ll tell you the answer today.
————
It’s just about this whether you can eat the overnight food
The rest of our food is actually a large natural medium.
Not only do we love to eat, but bacteria also love it.
A lot of overnight food is a large bacterial medium
Food spoilage is actually a process of continuous decomposition by microorganisms. The night is a long time, which gives bacteria the chance to grow on food.
Due to different preservation conditions and food types, some foods will have more bacteria, while others will have less bacteria. And if you eat food that carries a lot of pathogenic bacteria, you may get sick.
Therefore, whether the overnight food can be eaten or not is one thing: whether the bacteria exceed the standard.
————
These are the night foods that are known to be poisonous,
Actually, it can be eaten
tea
We often hear the rumor that “tea and water should not be drunk overnight, and it will produce nitrite carcinogens in multiples!”
But in fact, if you think about it carefully, it is no different from tea in the morning to tea in the afternoon and overnight tea only in terms of time
The only reason why you don’t recommend overnight tea is that it’s not good.
A study published in 2020 detected the nitrite content of Tieguanyin, black tea and green tea overnight. The results showed that after 12 hours, the content of nitrite in tea more than doubled to about 0.022mg/l, but they were still far below the safety limit of 1mg / L.
Therefore, overnight tea is not enough to endanger people’s health.
Green leafy vegetables
Another kind of food which is misunderstood because of “nitrite production”.
Many people say that because green leafy vegetables contain more nitrate, stored in the refrigerator overnight, nitrate will be converted into a large number of nitrite, so it will cause cancer.
It’s just bullshit.
The school of public health of Soochow University studied nitrite in overnight dishes. The results showed that nitrite was increasing with time, but the content was far less than the national standard (3 mg / kg for meat and 4 mg / kg for vegetable).
The nitrite intake from leftovers may not be as much as a ham sausage.
watermelon
Is it true that “there are hundreds of millions of bacteria in watermelon overnight, do you dare to eat after watching these”?
Some people have done relevant experiments.
Fujian Academy of Agricultural Sciences once analyzed the bacterial colonies of three different varieties of chilled watermelon. The results showed that most of the colonies in refrigerated watermelon at night were common bacteria in air and soil environment, and their pathogenicity was weak.
Therefore, fresh cut watermelon after overnight cold storage does not exist due to the proliferation of bacteria caused by food safety problems. After all, bacteria are also harmful and beneficial, aren’t they?
So just cover up the unfinished watermelon Fresh keeping film Put it in the refrigerator and refrigerate it. You can eat it as soon as possible~
Egg
Although raw eggs contain a certain amount of Salmonella, as long as the eggs are cooked, the bacteria will be killed.
And as long as refrigerated and sealed properly, it can be eaten overnight. Therefore, whether the eggs can be eaten overnight mainly depends on whether the eggs are cooked when they are boiled for the first time. It is no problem to cook the eggs overnight only after the eggs are cooked for the first time.
The same goes for tea eggs. Tea eggs need to be cooked twice. The first time is cooked, and the second time, the egg skin is broken, tea and other auxiliary materials are added, and then boiled. Therefore, tea eggs must be well cooked and can be eaten overnight.
————
These foods are not recommended to be eaten overnight
salad
It has been pointed out that raw vegetables and corn are the source of 132 different kinds of Enterobacteriaceae.
Because cold dishes or salads are not boiled and sterilized at high temperature, they are more likely to breed bacteria than cooked food.
Therefore, it is best to do a good job in advance of vegetable cleaning and heating.
Moreover, the taste of cold dishes will be strange after the next heating, so the cold dishes are not suitable for eating overnight.
Leftovers stored at room temperature
You must have heard mom say, “let the leftovers dry before you put them in the refrigerator.” There are some families, lunch leftovers, will take a gauze cover cover, until dinner a little hot to continue to eat.
But in fact, the risk of leftovers stored at room temperature is very high.
Ningbo Food Inspection Institute has done a statistics on the total number of colonies of overnight vegetables under different temperature conditions. The results showed that the microorganisms of overnight vegetables stored in 4 ℃ refrigerator had less proliferation, while those stored at 25 ℃ could proliferate after 6 hours.
Therefore, the danger is not “overnight”, but not putting food in the refrigerator in time.
Half cooked eggs
Raw egg itself will carry a certain amount of Salmonella, if not completely heated, bacteria are not completely killed, after overnight storage of loose eggs will be more likely to breed bacteria.
Therefore, if you buy hot spring eggs or soft boiled eggs from convenience stores, remember to eat them on the same day.
Unfinished milk and other dairy products:
Milk is rich in nutrients and is an excellent medium. It can breed different kinds of bacteria at 0-70 ° C. Therefore, it is not necessarily safe to put it into the refrigerator. Therefore, we still recommend that you drink milk as soon as you open it (especially in small packages).
If it is a large package of milk, one can not drink, then do not drink to the mouth, pour a little out each time, and then cover it as soon as possible and put it back into the refrigerator. After each time to drink, must first confirm whether there is a peculiar smell, to prevent deterioration.
Undercooked seafood
Generally speaking, meat dishes are OK overnight, but when reheated again, some B groups are lost vitamin But the protein and minerals can be completely retained, and the taste has no obvious change.
But fish and seafood are exceptions, because the proteins in these aquatic products are particularly vulnerable to microbial decomposition.
Studies have shown that shrimp, crab, shellfish and other aquatic products are often contaminated by low temperature resistant microorganisms, and these foods are usually heated for a short time in order to be fresh and delicious.
If it is not thoroughly cooked, not fully heated, and fails to kill all microorganisms, there is a risk that pathogenic microorganisms will multiply even if they are refrigerated in the refrigerator.
Leftovers from a dinner party
When the food is just out of the pot, there are few bacteria, because the process of cooking and heating is a process of high temperature sterilization.
However, if you eat it on the table for a while, you are pushed back and forth by different people’s chopsticks, and the saliva is mixed to mix, which is equivalent to helping the bacteria “inoculate”.
Therefore, if the food is ordered or cooked too much, it is better to set aside a part of it and refrigerate it as far as possible to reduce the contact between food and bacteria.
————
We don’t advocate eating overnight
At the end of the day, we don’t encourage you to eat overnight.
After all, apart from safety issues, the nutritional value and taste of “overnight food” may be affected.