Is it true that overnight watermelons will have a lot of bacteria?

Watermelon is a great fruit to cool off in summer, especially chilled watermelon, which quenches thirst and cools down. The reason why watermelon is very popular with everyone is mainly because watermelon has more water and tastes sweeter.

It can be done to cool down the body in a short period of time, and the amount of urine will also increase. Moreover, watermelon is rich in potassium, which can quickly replenish potassium that is easily lost with sweat in summer, preventing muscle cramps and body fatigue.

However, the watermelon is so big that it will definitely not be eaten at one time, so most people will choose to put it in the refrigerator and eat it when they need it the next day. But this will create a question, can you still eat watermelon after overnight? Will there be a large number of bacteria present?

Many people have heard the saying that watermelons can reproduce tens of thousands of offspring in just a few hours, even with plastic wrap. And I heard that a family of three had stomach trouble after eating overnight watermelon, and kept running to the toilet all day long. Even a 70-year-old man in Changsha had to be removed after eating overnight iced watermelon, which caused necrosis of the small intestine.

The microbiology laboratory of the Food Inspection and Testing Center recently conducted an experiment, mainly on "whether watermelons left overnight in the refrigerator will produce a large number of bacteria". The total number of bacteria in the watermelon samples was compared after 12 hours at room temperature 30 and refrigerator 4.

After research, it was found that the total number of watermelon bacteria preserved at room temperature 30 is 7x10 to the 6th power cfu gram, while the total number of watermelon bacteria refrigerated in the refrigerator 4 is 10 cfu grams, it can be seen that the gap is very large, and our country's regulations on fruits shall not exceed 1000cfu grams.

Therefore, the watermelon that has been left in the refrigerator overnight can no longer be eaten, the bacteria have far exceeded the prescribed level, and eating such watermelon is very bad for your health. The total number of watermelon bacteria that is placed in the refrigerator overnight is very small and relatively safe.

It should be noted that when the watermelon is put in the refrigerator, it will still breed bacteria on its surface, and refrigeration can only inhibit the reproduction of bacteria, but cannot freeze the germs. It is best not to leave the watermelon for more than 12 hours, and cover the uneaten part with a thin plastic wrap as soon as possible, which can isolate the watermelon from other foods in the refrigerator and avoid secondary contamination.

Overnight watermelon, fruit, food safety, food poisoning, plastic wrap, bacteria, food therapy, health.

It was found that the watermelon was opened within 4 hours, regardless of whether it was put in the refrigerator or not, whether it was pasted with plastic wrap or not, the total number of colonies on the watermelon was within the safety line, and it could be eaten with confidence, after 16 hours of refrigeration, the number of bacteria on the surface of the watermelon without film reached the danger line of 1000cfu grams, and the watermelon with plastic wrap created a closed environment conducive to the reproduction of bacteria, and the total number of colonies was as high as 4

Indeed, because it will have a lot of bacteria attached to its surface

It's true that overnight watermelons will have a lot of bacteria.

Yes, so it's best to finish watermelon and not overnight.

Yes, the taste of watermelon will change overnight.

Yes, it's really unhygienic, so be careful.

Yes, so it's best to eat it on the same day.

Its surface is infested with a lot of bacteria.

Yes, there will be a lot of bacteria, and it is better not to eat it.

Definitely, it's best not to eat overnight melons.

No, many people will eat watermelon overnight.

It is necessary to judge whether eating overnight watermelon will be poisoned according to the specific situation of the patient.

If the overnight watermelon is not infected with various pathogens such as bacteria and viruses and is not moldy or spoiled, the patient is usually not poisoned after eating it.

If you eat watermelon overnight on a hot summer day, the watermelon is not stored well, the watermelon has rotted or is infected by various pathogens such as bacteria, viruses, and parasites, and the patient may be poisoned after eating this watermelon.

Common poisoning reactions <> eating watermelon overnight include nausea, vomiting, abdominal pain, bloating, diarrhea, etc. In severe cases, severe conditions such as fever, exhaustion, weakness, and dehydration may occur.

So, is it really not possible to eat such a watermelon?

In fact, this experiment does not mean that if you keep the habit of staying in the refrigerator overnight, you will not be able to eat and there will be problems after eating, but it reminds you to pay attention to the correct use of knives and cutting boards, to distinguish different foods when cutting them, and not to cut them all at once. Watermelon can be stored in the refrigerator. Here are a few things to keep in mind for safe eating:

First of all, how to cut watermelon properly, I recommend that you use a special knife and cutting board to make sure the knife is clean.

Second, don't rush to eat after chopping vegetables. Cover the watermelon you want to keep fresh with plastic wrap and put it in the refrigerator in time. By the way, you should keep it separate from other foods, especially cooked food. There should also be a distance between raw and raw foods.

I recommend that you try to eat the leftovers within 12 hours, rather than after a full day. Of course, the best thing to do is to advise you not to buy watermelons that are too big, buy small ones, and eat them separately. It is best to eat it all at once. Such watermelons are fresher, taste better and are healthier.

If you can do this, watermelon can be eaten for a day, but if you are not satisfied with these points, such as cutting other foods with a knife or putting them in the refrigerator too late, it may greatly increase the bacterial content in it. At this point, it is recommended that you do not consume it again overnight.

I would also like to mention that we should not think of refrigerators as a universal thing. Although it provides great convenience for food preservation, it is not completely safe. We should use it properly, especially in the summer. Regarding the use of the refrigerator, please note the following:

Clean the interior and exterior regularly, especially the seals on the doors. Don't ignore it when cleaning. After that, let it dry naturally.

When storing food, don't overfill it. Divide food into crisper bags or crispers before putting them in to avoid cross-flavoring. Raw and cooked foods must be separated.

For uneaten leftovers, if they are fried, it is recommended to store them for no more than 12 hours, cook them for no more than 24 hours, and cold cuts are not recommended for storage.

This is true, because a lot of bacteria are produced on the surface of the watermelon overnight, and if you eat too much, you will get food poisoning, so don't eat the overnight stuff if it spoils.

Depending on the specific situation, if you use a clean cutting board and knives to cut watermelon, wrap it in plastic wrap and put it in the refrigerator, it will not breed bacteria, on the contrary, watermelon will be contaminated with germs, and it should not be eaten overnight.

It's true, because watermelons can grow a lot of bacteria. Eating it in the stomach is especially easy to cause diarrhea, and it can also cause poisoning.

Introduction: In summer, many people like to eat watermelon, watermelon is refreshing and delicious and juicy and sweet, so it is also a very good fruit to relieve the heat, and some people choose to put watermelon in the refrigerator overnight because they have not finished eating. Does keeping watermelon in the fridge overnight breed bacteria?

Although the refrigeration temperature in the refrigerator is relatively low, there are bacteria that can survive, so some bacteria will appear in the refrigerator. It's just that because of the low temperature, the bacteria are not so active and the multiplication rate is not very fast, which is also the reason why people can use the refrigerator to refrigerate food for a period of time. Watermelon will also come into contact with the air after cutting, so there will be some bacteria, plus watermelon has a relatively high sugar content, itself is a very high-quality nutrient, so putting watermelon in the refrigerator overnight will breed bacteria, and it will also affect the taste.

Usually, watermelons taken out overnight in the refrigerator and freshly cut watermelons have a completely different taste. Sometimes the surface of the watermelon will also adhere to the odor of the refrigerator, plus bacteria, so it makes people feel more unpalatable. It is recommended to pay attention to the amount of watermelon when cutting, if you can't eat it on the same day, then don't cut it, if you can eat it on the same day, then you can enjoy delicious watermelon.

After putting the watermelon in the refrigerator and taking it out, it is best to cut off the surface layer before eating.

Whether it is a refrigerator or a freezer, the refrigerator space needs to be cleaned in time. There are often some cooked meals in the refrigerator, which will have a distinct taste and will also affect the overall environment of the refrigerator. Although the temperature in the freezer is relatively low, these times are often placed in the freezer and will have a certain impact on the refrigerator.

Therefore, it is necessary to clean it regularly, unplug it first, take out all the ingredients inside, clean each locker, and put it in after drying, so that your refrigerator will become cleaner again.

Of course not. Because all refrigerators nowadays have a sterilization effect, there will be no bacteria.

Watermelon can grow bacteria when left in the refrigerator overnight, and it will be better to cover the watermelon with plastic wrap before putting it in the refrigerator.

Yes. Because there is a lot of sugar in watermelon, such things are very easy to breed some bacteria.

Bacteria will definitely grow. It can also directly affect a person's stomach, so it is best not to eat watermelon on the 2nd day of the overnight stay.

Yes, this is a very serious problem, and some bacteria can multiply at low temperatures, which is very dangerous.

In order to accurately answer this question, the microbiology laboratory of Ningbo Food Inspection and Testing Center has done special experiments.

Purpose of the experiment

Simulates two common ways to store watermelons in everyday life:

1.Store at room temperature 30 °C;

2.Store in the refrigerator;

Through experiments, to determine, should the watermelon that cannot be eaten be wrapped in plastic wrap?

Experimental Methods

According to food safety standards, the total number of colonies is quantitatively detected. （Total number of coloniesIt reflects the cleanliness of the food, and the higher the value, the "dirtier".

Experimental process

Don't look at the simplicity of "eating melons", if you treat it in a scientific and rigorous way, there are university questions in it.

In the laboratory, two ways of storing watermelon in daily life were simulated, one was at room temperature 30 and the other was stored in the refrigerator4. Then the cut watermelon was divided into two situations: wrapped in plastic wrap and not wrapped in plastic wrap, and placed for 4 hours, 8 hours, 16 hours, 24 hours, and 48 hours respectively, and then the total number of bacteria in the watermelon sample was calculated.

It was found

in placeAfter 4 hours and 8 hoursWhether it is put in the refrigerator or not, with or without plastic wrap, the total number of bacteria is basically 20cfu grams, starting from 16 hours, the bacteria begin to multiply, and after 24 hours, the bacteria multiply exponentially.

That is to say,If the watermelon is placed for less than 8 hours, it does not matter whether it is used in plastic wrap or whether it is put in the refrigerator or not.

But placedMore than 24 hoursWatermelons stored at room temperature have a million times more bacteria than watermelons stored in the refrigerator (with or without plastic wrap). It is recommended that watermelon that has been stored at room temperature after 24 hours should not be eaten.

If the watermelon is too big to eat in a day, it is best to choose to put it in the refrigerator. Home refrigerators generally have more things, so it is safer to cover them with plastic wrap. Some families will remove the surface of the watermelon taken out of the refrigerator before eating, whether this method has the effect of reducing bacteria, see the results given to us by the laboratory.

Experimental results

The significant difference occurred at simulated room temperatureAfter 16 hours of storage, the watermelon with the surface removed is significantly less than the watermelon without the surface removed.

When stored in the refrigerator, whether it is 24 hours or 48 hours, the total number of bacteria stored for 48 hours on the surface of the watermelon is 10, on the one hand, because in the refrigerator of 0 -4, this environment can inhibit the bacterial reproduction rate, and on the other hand, after the surface of the watermelon is removed, the bacteria on the surface are removed, so that it is safer and more hygienic to eat watermelon. Thus illustratedAfter watermelon is stored for a long time, cutting off the flesh on the surface can reduce the number of bacteria.

To summarize the correct posture of "eating melons in summer":

1.Before eating melons, you must remember to wash melons; Before cutting melons, you must remember to wash the knife;

2.If it is eaten within 8 hours after cutting, it can be placed in a ventilated place indoors, without covering with plastic wrap, and can be covered with a sarong, etc.; If you like the cool taste of refrigeration, you can choose to put it in the refrigerator with or without plastic wrap;

3.If you cut it and eat it for more than 16 hours, remember to store it in the refrigerator.

Bacteria will grow on the surface of the watermelon after 24 hours of cutting, and leftover watermelon can be covered with a layer of plastic wrap and then put in the refrigerator for refrigeration.

Whether it is a whole half or cut into small pieces of watermelon, store at room temperature for more than 4 hours in a hot high temperature environment, bacteria will breed within 6 hours, refrigerate for more than 24 hours, cover with thin plastic wrap or put directly into the refrigerator to refrigerate watermelon in the refrigerator for a maximum of 24 hours, you can cut off the surface of about 1 cm before eating.

Bacteria can grow after three hours of incision. At this time, keep the watermelon in plastic wrap and put it in the refrigerator.

<>1. Watermelon has more bacteria overnight at room temperature and is inedible; It is relatively safe after refrigeration.

2. The total number of bacteria in the watermelon samples was compared after 12 hours of clumping at room temperature 30 and refrigerator 4. After research, it was found that the total number of watermelon bacteria preserved at room temperature 30 is 7x10 to the 6th power cfu gram, while the total number of watermelon bacteria refrigerated in the refrigerator 4 is 10 cfu grams, it can be seen that the gap is very large, and our country's regulations on fruits shall not exceed 1000cfu grams.

3. Therefore, the watermelon that has not been put in the refrigerator overnight can no longer be eaten, the bacteria have far exceeded the specified level, and eating this watermelon containing this core is very bad for health. The total number of watermelon bacteria that is placed in the refrigerator overnight is very small and relatively safe.