Refrigerator ≠ safe, take a look at who the “dangerous elements” are in the refrigerator!

The tragedy that occurred in October 2020 in Jixi, Heilongjiang, where a family all died after eating sour soup at a dinner party, has brought up a question worth pondering for everyone - in daily life, does storing various foods in the refrigerator keep them fresh or does they slowly turn into poison? Is it really safe to store food in the refrigerator?

Nowadays, although every household uses refrigerators, not many people really understand them. Although refrigerators can maintain low temperatures for a long time, since refrigerators are a closed environment, once the food inside is spoiled, bacteria will multiply in large numbers. Perhaps some people will ask, in such a cold environment, are bacteria so "tough"? The answer is yes. Some bacteria are much "tougher" than us humans. Not only are they not "afraid" of the cold in the refrigerator, they can also "enjoy themselves" in the refrigerator, form "families", and quickly grow and reproduce more bacteria.

Refrigerator ≠ safe

Refrigerators use a method of lowering the temperature to keep food relatively fresh, inhibit the reproduction of microorganisms in food, catalyze enzymes, and reduce the oxidation rate of food. However, it is worth noting that the low temperature in the refrigerator cannot completely kill the microorganisms in food. Some cold-loving microorganisms such as Flavobacterium, Pseudomonas, Achromobacter, and a few yeasts can grow slowly in a low-temperature environment. As food is stored in the refrigerator for a longer time, it will also spoil as the number of microorganisms increases.

The refrigerator is not a "safe" for food. Photo: Ruijing Creative

Therefore, although refrigerators can keep food fresh, the storage conditions will vary depending on the food. Every summer, there are always several news reports of "chilled watermelon cross contamination causing poisoning". In fact, this is also a reminder that using refrigerators to keep food fresh is not as effective as using fresh ingredients. Sometimes, even wrong operation can cause food poisoning. The refrigerator is not a "safe" for food, it is just a "small hotel" where food stays temporarily.

The pervasive "dangerous elements"

Many families have the problem of refrigerator odor, so they go to the supermarket to buy various deodorizers or use a lot of orange peels to improve the smell in the refrigerator. In fact, this constant odor is not a simple smell, but comes from the gas produced by bacterial metabolism, such as hydrogen sulfide, methylamine, etc. A research institute once conducted a "family hygiene survey" in 9 countries including Australia, Canada, and the United States. The results showed that 46% of family refrigerators have excessive bacteria, including Listeria, E. coli, and Salmonella. Among them, the most common "dangerous molecule" is Listeria. Why is it typical? Because it is always everywhere and pervasive.

Listeria map/web

Listeria can hide in a variety of foods, the most common of which are various meats, such as raw meat, cooked meat, pickled meat, etc. It is also common in some unpasteurized milk, eggs, vegetables, fruits, and even some unfinished food put in the refrigerator. As a cold-resistant bacterium, it has a very strong ability to survive and can still grow slowly in a refrigerated environment of 0~4℃. In addition, it is also resistant to dryness and high-salt environments. Infected people often develop diseases such as meningitis, sepsis, and endocarditis, and may even cause miscarriage in pregnant women.

Of course, there is no need to panic if you encounter "dangerous elements". Generally speaking, healthy adults often do not have particularly serious consequences after infection, and some people will not get sick even if they carry bacteria. They often like to target some susceptible groups, such as pregnant women, infants, the elderly or people with low immunity. Studies have shown that the probability of pregnant women being infected with Listeria is about 20 times higher than that of ordinary people. If a pregnant woman is infected with it, the miscarriage rate is 30%.

Four types of food will go bad quickly if placed in the refrigerator

Some tropical fruits

Common ones include bananas, mangoes, avocados, pineapples, etc. If these tropical fruits are put into the refrigerator before they are ripe, the low temperature may inhibit their ripening. In addition, they are very fragile and afraid of "frostbite". It is generally recommended to store them at around 12℃ and put them in a cool place indoors. Too low a temperature will cause these tropical fruits to "frostbite", blacken, rot, etc.

Starchy foods

Common ones include steamed buns, flower rolls, bread, etc. Starch-rich foods are prone to starch aging after being placed in the refrigerator, making the food hard and affecting the taste of the food. If you really can't finish it, it is recommended to put it in a food preservation bag and freeze it.

Some vegetables

Green peppers, cucumbers, tomatoes, etc. are not suitable for storage in the refrigerator. Green peppers are generally stored at 7-9 degrees Celsius. If the temperature is too low, the green peppers will be "frozen", softened or even deteriorated. If tomatoes are placed in the refrigerator when they are not ripe, they will no longer mature. If they are kept for a long time, they will fall apart, dark spots will appear on the surface, and they may even become sour and rotten. In addition, foods such as onions, cabbage, garlic, and radishes can also be stored for a long time at room temperature, so they do not need to be placed in the refrigerator.

High-salt and high-sugar foods

High-salt foods such as bacon, pickles and other preserved foods, and high-sugar foods such as honey, preserved fruits, and candies often have high salt and sugar content. When stored at room temperature, microorganisms cannot reproduce and grow. Therefore, these foods only need to be placed in a cool and ventilated place. In addition, if honey is refrigerated, it is easy to cause crystallization of glucose, and chocolate will also have fat crystallization due to being placed in the refrigerator for a long time, which will affect the taste.

Some foods are not suitable for being stored in the refrigerator. You should learn how to use the refrigerator properly. Image/Rui Jing Creative

The correct way to open the refrigerator

Separate raw and cooked food

In the refrigerator, it is generally recommended to put cooked food on the top two layers, such as leftovers, milk, cooked food, etc.; raw food on the bottom two layers, such as raw vegetables, raw tofu, etc. It is recommended to cover cooked food with plastic wrap. If there are a lot of leftovers, you can choose to store them separately. All raw food is best packaged separately, such as putting a plastic bag for each vegetable.

Partition storage

In the refrigerator, the temperature varies at different locations, and the best location for storing different types of food is often different. Generally speaking, the bottom of the refrigerator is colder than the top, and the deep inside is colder than the door. Therefore, it is recommended to place foods that are afraid of freezing, such as vegetables and fruits, on the outside; bean products, milk, and leftovers that are not afraid of freezing can be pushed closer to the inside. Fresh meat, fresh fish, shrimp, etc. are the most susceptible to spoilage when not frozen, so it is best to place them in a 0℃ refrigerated fresh-keeping box.

70% full

When storing food in the refrigerator, it is recommended to store it at most 70% full. Leave enough space in the refrigerator to ensure cold air circulation to ensure that the temperature can reach the ideal value. Storing too much food will affect the normal cooling function of the refrigerator.

Text/Wang Qian