In the blazing hot summer, watermelons have become people’s preferred fruit for beating the heat and quenching thirst. However, controversies surrounding the preservation of watermelons have never ceased, especially the claim that “watermelons wrapped in plastic wrap and refrigerated attract more bacteria,” which has spread widely on the internet and caused considerable concern among consumers.
So, what is the truth? This article will uncover the mystery through detailed analysis, experimental verification, and expert interpretations.
I. Online Rumors Spark Concern
In recent years, controversies about the preservation of refrigerated watermelons have escalated, especially the claim that “watermelons wrapped in plastic wrap and refrigerated attract more bacteria,” which has made many consumers wary.
This claim initially originated from an online news report about a 70-year-old woman in Zigong who experienced severe health problems and even ended up in the ICU after consuming watermelon that had been refrigerated for two days and wrapped in plastic wrap.
This incident quickly went viral on the internet and sparked widespread discussion.
Many netizens expressed similar experiences and believed that plastic wrap provided a breeding ground for bacteria during refrigeration.
However, others held different views, arguing that plastic wrap only served to isolate air and prevent moisture loss and would not lead to bacterial growth. So, what is the truth?
II. Experimental Verification: Plastic Wrap Is Not the Culprit of Bacterial Growth
To verify this claim, we conducted an experiment. The experimental process is as follows:
Experimental Preparation: We purchased two watermelons of similar size and maturity from the market to ensure comparability of the experimental subjects.
Then, we cut each watermelon in half and tightly wrapped the cut section of one half with plastic wrap, while the other half was left exposed to the air.
Refrigeration: The processed watermelons were placed in two identical refrigerator compartments with the temperature set to 4°C to ensure the stability of the experimental environment.
Sampling and Testing: After 12 hours, 24 hours, and 48 hours of refrigeration, we took samples from both groups of watermelons for bacterial content testing.
The testing process was conducted in a sterile environment to ensure the accuracy of the results.
Testing Results: After testing, we found that after 12 hours of refrigeration, the bacterial content of both groups of watermelons was low and showed little difference.
However, after 24 and 48 hours of refrigeration, although the bacterial content of both groups increased, there was no significant difference between the wrapped and unwrapped watermelons.
These experimental results contradict the widely circulated online claim. In fact, plastic wrap does not lead to more bacterial growth during refrigeration. On the contrary, it effectively isolates airborne bacteria and reduces contamination on the watermelon surface.
III. Expert Interpretation: The Correct Use of Plastic Wrap
Regarding these experimental results, we interviewed several experts in the field of food science. They stated that plastic wrap plays an important role in food preservation, but the key lies in its correct use.
Preventing Moisture Loss: Plastic wrap effectively prevents moisture loss from the food surface, maintaining its taste and nutritional value. This is particularly important for fruits like watermelons.
Isolating Air and Bacteria: Plastic wrap isolates airborne bacteria and contaminants, reducing contamination on the food surface. However, this does not mean that plastic wrap can kill bacteria or inhibit their growth.
Therefore, when using plastic wrap, attention should still be paid to the hygiene of the food. If the food is already contaminated or bacteria are present, using plastic wrap will not change this fact.
