Rumor 1 :Watermelon wrapped in plastic wrap and stored in the refrigerator will cause gastrointestinal
/✗:This is a wrong statement
The claim that “wrapping watermelon in plastic wrap increases bacteria by 10 times” originated in 2013, when a media outlet conducted an experiment by cutting a watermelon into two halves, covering one half with plastic wrap and leaving the other half uncovered. They found that the wrapped half had 1012 more bacteria than the uncovered half, leading to the conclusion that people should avoid using plastic wrap to refrigerate fruits as it promotes bacterial growth. However, is this really the case?
Professionals explain that the speed of bacterial reproduction depends on two factors: the degree of contamination of the food and the storage environment of the food. Covering the surface of watermelon with plastic wrap itself does not cause bacteria to proliferate rapidly. Instead, factors such as storing the watermelon in an unclean environment or at excessively high refrigerator temperatures are the main culprits behind rapid bacterial growth.
Moreover, uncovered frozen watermelon sees faster microbial growth, and its taste, texture, and appearance are inferior to those wrapped in plastic wrap. The role of plastic wrap is actually to prevent water loss, reduce bacterial contamination from the air, and prevent flavor mixing. If cut watermelon is left at room temperature for too long, bacteria will grow and pose a health hazard.
Rumor 2 :Intestinal necrosis may occur two hours after eating iced watermelon
/✗:This is a wrong statement
The bacteria in the intestine are divided into beneficial and harmful bacteria, and it is not easy for harmful bacteria to defeat beneficial bacteria and dominate.
From a pathophysiological perspective, the intestinal wall is divided into the mucosa, submucosa, muscularis, and serosa from inside to outside, which are tightly connected with the surface mucosal epithelial cells, forming an effective “defensive barrier.” Assuming that the bacterial content in iced watermelon is indeed high, even if these bacteria enter the intestine, it is impossible to cause intestinal necrosis in a very short period of time. The entire process is quite complicated.
For the disease to occur, the bacteria first need to proliferate to a sufficiently large number, large enough to replace the original probiotics in the intestine, and then destroy the intestinal mucosal barrier and invade the intestinal wall. Next, under the action of the toxins produced by the bacteria, there will be severe spasms and dysfunction of the mesenteric blood vessels, which may ultimately lead to “intestinal necrosis.”
The entire pathological process generally takes “several hours to several days.” The claim that “eating watermelon can lead to intestinal necrosis within two hours” is exaggerated and does not conform to reality and scientific principles.
So, how to eat watermelon scientifically and safely?
- Buy fresh and whole watermelons
It is recommended to avoid purchasing pre-cut watermelons as it is unclear how long they have been stored.
- Use clean tools for cutting watermelon
If the fruit knife and cutting board are contaminated with bacteria, it will affect the quality of the watermelon. It is best to use a dedicated fruit knife and avoid mixing it with a kitchen knife. Ensure the knife and cutting board are clean before cutting the watermelon, preferably by rinsing the knife with boiling water repeatedly.
- Store at room temperature for no more than 3 hours
In high temperatures, regardless of whether plastic wrap is used, a large number of bacteria will proliferate within about 6 hours. Within 3 hours, there will be minimal bacterial growth, so it is best to cut and eat the watermelon immediately.
- Proper refrigeration storage
Using plastic wrap is still a good method to prevent cross-contamination and flavor mixing of ingredients. However, if there is a separate storage space for watermelon in the refrigerator that does not cause flavor mixing or moisture loss, it is not recommended to cover it with plastic wrap. The refrigerated storage time should not exceed 24 hours.
- Remove the outer layer before reheating
Bacteria mainly proliferate on the outer surface of the cut, while the inner layers have a lower bacterial reproduction rate. Therefore, it is safer to remove about 1cm of the outer skin layer before reheating.
