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Does a refrigerator emit radiation? Does it affect the taste of food? Will keeping watermelon in the fridge cause diarrhea? Not everyone knows the answers to these questions.
1. Do you truly understand how to use a refrigerator?
Does a refrigerator emit radiation? Does it affect the taste of food? Will keeping watermelon in the fridge cause diarrhea? Not everyone knows the answers to these questions.
Does a refrigerator emit radiation?
Yes, but it's not harmful.
Essentially, household appliances can generate magnetic fields, and these fields spread into the surrounding environment in the form of electromagnetic waves, also known as radiation.
However, radiation can be categorized into two types based on intensity. One is ionizing radiation, which has high energy and can break chemical bonds, causing harm to the human body. The second type is non-ionizing radiation. The energy of radiation generated by household appliances is very low and belongs to non-ionizing radiation.
Of course, low energy is still energy. So, does prolonged exposure have any effect on the body? On this matter, scientists worldwide have conducted tens of thousands of studies, and so far, no evidence of health effects from non-ionizing radiation has been found.
The radiation intensity of the refrigerator (highlighted in red). Source: WHO
However, as a precaution, there are requirements for the magnetic field intensity of household appliances, which should not exceed 100 µT. According to estimates by the World Health Organization, the magnetic field intensity at a distance of 3 cm from the refrigerator is about 0.5 µT to 1.7 µT, much lower than the limit. So, you have nothing to worry about.
Does a refrigerator affect the taste of food?
Yes, but it also has its own advantages and disadvantages.
Because taste is a highly subjective concept. Therefore, let's take starch as an example to talk about the effect of low temperature on its taste.
There are two types of starch in rice and wheat: amylose, which has a tightly packed structure like a string, and amylopectin, which has many branches but a less dense structure. During cooking, both types gradually break down and become fluid. Subsequently, as the temperature decreases, they return to their original state. However, amylopectin, after synthesis, will have a more compact structure, forming resistant starch. This resistant starch slightly affects the taste but has a very low postprandial blood sugar index. That is, consuming more resistant starch slows down the increase in blood sugar compared to regular starch. This metabolic process is influenced by three factors: amylose content, temperature, and fat content. In summary, changes in food taste due to low temperatures are sometimes not necessarily negative.
However, experimental results show that nitrite levels actually increase when excess food is left at room temperature for 48 hours. However, it does not exceed the safety limit. And if placed in the refrigerator, the rate of nitrite increase will be slower.
Keeping watermelon in the refrigerator does not cause diarrhea; it's a matter of bacteria. Due to their preferred temperature characteristics, bacteria can be divided into three types: low-temperature, high-temperature, and mesophilic bacteria, which grow fastest at around 37°C. The refrigerator's temperature is mainly 4°C, lower in the freezer, thus delaying the development of bacteria significantly. However, delay does not mean destruction. If bacteria exist in the food, they can still multiply and harm humans.
Principles of Using the Refrigerator Correctly
There are four main principles. First, take time to wash fruits, vegetables, and meat before putting them in the fridge. Pay special attention to washing hands thoroughly as bacteria can transfer from hands to food before placing them in the refrigerator. Second, raw and cooked foods should be handled separately to avoid cross-contamination in the fridge. Third, during food processing, we must pay attention to temperature and time. For some types of food, thorough cooking is necessary to kill disease-causing microorganisms. Finally, processed food should be refrigerated as soon as possible (within 1-2 hours) to avoid contamination by the environment. Also, it's best to consume them as soon as possible (preferably within 1 week), including frozen meat. Lastly, regularly clean the refrigerator to protect both the appliance and your health.
