Can you eat overnight watermelon? What are the dangers of eating overnight watermelon?

What are the dangers of eating overnight watermelon? Can we eat overnight watermelon? Let's learn about the reasons why overnight watermelon can't be eaten and how to store it best.

Why can't you eat overnight watermelon?

The speed of bacterial reproduction in overnight watermelons depends on two factors: the degree of food contamination and the environment in which the food is stored. The number of colonies is higher after the cut watermelon is covered with plastic wrap. This cannot be seen as a problem with the plastic wrap alone. Whether the knife and cutting board used to cut the watermelon have been cleaned and sterilized is also the key. Should the refrigerated watermelon be wrapped with plastic wrap? Experts say that if there is a separate space in the refrigerator to store watermelons, it will not cause odor contamination and water loss, so it is not recommended to cover it with plastic wrap. It is indeed not advisable to keep uneaten watermelons for a long time. Cut watermelons can generally be left at room temperature for a maximum of 4 hours. It is safe to refrigerate them in time.

Zhao Yongyi, director of the Clinical Nutrition Department of the First Affiliated Hospital of Guangdong Pharmaceutical University, pointed out the problems: First, the method of preserving watermelons in this experiment was at room temperature, but most citizens know that overnight watermelons need to be refrigerated; second, the experiment was too accidental, and the "hundreds of millions" of bacteria that appeared in the test may have come from the air, knives, or even plastic wrap, and the relationship with "overnight" is uncertain; finally, whether these bacteria are pathogenic bacteria also needs further identification. "But what is certain is that uneaten watermelons should not be kept for a long time at room temperature, and they must be refrigerated in time for safety," Zhao Yongyi said.

According to food experts, after wrapping the fruit with plastic wrap, a relatively closed space is formed between the fruit and the plastic wrap, which provides better conditions for bacterial reproduction. However, "the plastic wrap is produced at high temperatures and cannot carry bacteria. The bacteria in the plastic wrap must have been contaminated by improper storage after it was opened."

How to store watermelon

There is still a lot to learn about how to store watermelons. Here are two methods: Method 1: Cover the surface with clean plastic wrap. Method 2: Use a clean spoon to scoop out the watermelon and put it in a clean, airtight box. However, the refrigeration time should not be too long, and watermelons are cold in nature. People with poor spleen and stomach should not eat too much, especially frozen watermelons. Therefore, refrigerated watermelons should be taken out of the refrigerator a while in advance before eating.

Of course, it is still recommended that you eat the cut melon immediately, first to avoid leaving it and then worrying about whether to waste it, and second to avoid excessive waste of the small amount of vitamins in the watermelon. Eating watermelon is obviously for the enjoyment of cooling off, but don't let it end up causing you to get sick.

Precautions for eating watermelon

Experts suggest that instead of worrying about the number of bacteria, it is better to scald the knife with boiling water

Regarding the test results, Zhou Kang, associate professor of the School of Food Science at Sichuan Agricultural University, said that 3,800 bacteria per gram is not a lot. For example, the raw meat bought by citizens has about 100,000 bacteria per gram, and some even more. Zhou Kang said that because meat and watermelon are eaten differently, many bacteria in raw meat will die after being fried.

According to the GB17401-2003 "Standard for Hygiene of Puffed Foods" issued by the state, food can be safely eaten if there are less than 10,000 bacteria per gram. "Comparatively speaking, the number of bacteria in overnight watermelons is much lower than this number." Zhou Kang said. In this test, the 3,800 bacteria per gram may have many sources, such as bacteria on the knife or bacteria on the plastic wrap. According to the number of bacteria detected, instead of worrying about the preservation of watermelons, it is better to work hard on the knife used to cut watermelons. "If the knife is contaminated, the number of bacteria is far more than this number." Zhou Kang suggested that citizens must use fruit knives and kitchen knives separately. Think about if a knife that has just been used to cut meat is simply washed with cold water and then used to cut watermelons. Not only will there be a lot of bacteria, but it may also contain pathogenic bacteria, which is very risky. It is recommended to scald the knife with boiling water before cutting.