Many people ignore these "signals" of food spoilage

Many of the foods we come into contact with every day

It is a delicious and nutritious food when fresh

But once it is not fresh, sprouts or even deteriorates

It will produce toxins that are harmful to your health

It may even endanger life

Don't be careless!

Plus, many people like to hoard food.

I can't bear to throw it away even after the expiration date

Sometimes in order to avoid waste

They also heat up expired and spoiled food before eating it.

Can spoiled food still be eaten after being exposed to high temperatures?

Let’s find out together!

The harm of spoiled food to the body

Food spoilage refers to the change in the physical and chemical properties of food under the influence of external factors, resulting in a decrease in quality, change in color, deterioration in taste, and even the emission of unpleasant odors, thereby losing its edible and nutritional value.

1. Spoiled food can cause poisoning

Many foods will produce a large number of bacteria and toxins after they go bad. In particular, some fresh aquatic ingredients such as fish, shrimp and crab will produce amines and hydrogen sulfide that are harmful to the human body after they go bad. After these substances are absorbed by the human body, people will have obvious poisoning reactions. The most common manifestations are skin flushing, conjunctival congestion, chest tightness and headache.

2. Spoiled food can cause gastrointestinal discomfort

When food goes bad, it will produce a large number of bacteria. After entering the human stomach and intestines, these bacteria will multiply rapidly and affect the balance of probiotics in the stomach and intestines, causing people to have gastrointestinal discomfort. In severe cases, people will experience nausea, vomiting, diarrhea and other adverse symptoms, which will directly endanger people's health.

3. Spoiled food can cause cancer

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Carcinogenesis is a serious consequence of eating spoiled food, and is also one of the main hazards of spoiled food to the human body, especially rotten ginger. During the decaying process, a highly toxic safrole will be produced. After this substance enters the human body, it will cause obvious poisoning reactions, and will cause liver cell damage. It will increase the incidence of common cancers such as esophageal cancer and liver cancer, and in severe cases it will directly endanger people's lives.

Can spoiled food still be eaten after boiling?

Since food spoilage is caused by external microorganisms, can we kill the microorganisms in the spoiled food by using high temperatures so that it can be eaten safely?

The answer is no !

This is because some bacteria are resistant to high temperatures and cannot be completely eliminated even after heating . In addition, most of the toxins contained in spoiled food cannot be reduced or eliminated by high temperatures, such as aflatoxin and fumonisin, which are very heat-resistant. In other words, spoiled food can still cause vomiting, diarrhea, food poisoning, etc. after boiling.

In addition, even if only part of the spoiled food is rotten and the rest looks intact, it is not suitable to continue eating. For example, moldy fruit is common in life. Studies have shown that for some moldy fruits, even if the rest looks normal to the naked eye, they contain a lot of mold. If you continue to eat them at this time, it will only increase the risk of getting sick.

What are the characteristics of spoiled food?

1. Yogurt becomes sour

The acidity of yogurt is limited. If yogurt is separated from the cold chain during storage and logistics, such as being left at room temperature or outdoors, lactic acid bacteria will multiply rapidly, causing the acidity of the yogurt to increase and exceed the acceptable range. Such yogurt will taste very sour, and the activity of lactic acid bacteria will decrease, and the degree of milk protein denaturation will increase, which is not conducive to human absorption and gastrointestinal health. The longer the yogurt is stored, the harder it is to guarantee its quality. Therefore, do not buy a lot of yogurt at one time, and try to buy and drink it now.

2. Potatoes turn brown after being cut, and freshly squeezed juice changes color

Fruits, vegetables and potatoes naturally contain "phenol oxidase", which is also rich in "polyphenols" with antioxidant effects. If they come into contact with each other and are combined with oxygen, "enzymatic browning" will occur, that is, phenol oxidase catalyzes the oxidation reaction of colorless polyphenols to generate colored "quinones". These quinones can polymerize with each other, making the color darker and darker. Although no harmful substances are produced in this process, the antioxidant capacity of polyphenols decreases after browning, and it is also accompanied by the loss of vitamin C. To avoid this reaction, the raw materials should be scalded with boiling water before juicing to inactivate phenol oxidase, or a piece of vitamin C should be added when juicing. If potatoes, lotus root slices or yam cannot be cooked immediately after cutting, they should be placed in water with vinegar.

3. Roasted meat turns brown and baked buns turn yellow

After being cooked at a high temperature of more than 120°C, foods containing carbohydrates and amino acids will turn yellow and brown, and release an attractive aroma. This reaction is called the Maillard reaction. For example, braised pork, roast duck, toast, pancakes, deep-fried... almost all kinds of cooking that turn the color darker and browner promote the Maillard reaction. Acrylamide (a carcinogen) is a byproduct of this reaction. It has nothing to do with aroma and has no color. But generally speaking, the darker the color and the stronger the aroma of the food after heating, the higher the acrylamide content. Therefore, do not bake steamed bread slices and bread slices to the extent that they are too yellow, and try to eat less baked, fried, and puffed potato products, such as potato chips.

4. Blanching purple cabbage turns blue

Strawberries, purple cabbage, purple sweet potatoes, purple rice and other foods are rich in anthocyanins, which are powerful antioxidants that can protect the human body from free radical damage. The characteristics of anthocyanins are that they are red in acidic conditions and usually turn blue in alkaline conditions. There may also be transitional colors such as purple and green in the middle, and the water in the north is generally weakly alkaline. These color changes are normal and can be eaten with confidence, but generally speaking, anthocyanins are relatively stable under acidic conditions. For example, adding a little vinegar will make the purple cabbage more red.

5. Green leafy vegetables turn yellow after frying

The reason why green vegetables appear green is mostly due to the magnesium ions in chlorophyll. When light shines on chlorophyll, porphyrin (a compound in chlorophyll) containing magnesium ions will make other colors of light have no return, and only reflect green light. However, during the heating process, chlorophyll is very unstable. Studies have shown that acetic acid (acetic acid) in vinegar will destroy the structure of chlorophyll, turning chlorophyll into "de-pheophytin", and the vegetables will quickly turn yellow-brown. Therefore, add less vinegar or no vinegar when stir-frying green leafy vegetables.

6. Floccules appear after heating milk

There are two reasons why flocs appear after heating milk. First, certain proteases in milk change the structure of the protein in milk, thereby destroying the stability of milk and causing denaturation and coagulation during heating. Although such milk has not expired, it is not recommended for drinking. Second, the proliferation of residual microorganisms in milk causes the acidity of milk to change, further destroying the stability of milk, resulting in flocs. In short, milk with flocs after heating is not recommended for drinking.

7. The surface of tofu is sticky

Tofu, like meat, is a protein-rich food, so it is easy to breed bacteria in poorly ventilated and high-temperature environments, making the tofu sticky. If the bacteria are pure, there is no need to worry about its safety. However, there are many bacteria in the home environment, which may be mixed with harmful bacteria. Some of them will produce toxins, and washing with hot water cannot guarantee that they will be completely washed away. Therefore, sticky tofu is not recommended for consumption. In addition, high-protein foods such as dried tofu and animal offal should also be thrown away if there are sticky or slippery substances on the surface.

8. Vinegar makes your hair grow white

The "white hair" in vinegar is likely to be mold film produced by Mucor, which is widely present in the environment. If the white hair in vinegar is simply caused by Mucor, it will not be a big problem to remove the mold film and continue to eat it. However, there are other pathogens in the air. If they also reproduce in vinegar, they may pose a health threat. Therefore, it is best not to continue to eat vinegar with white hair.

In conclusion

Food safety is no small matter

Be wary of any food spoilage

Mild cases may cause diarrhea and vomiting

Serious cases can be life-threatening

The safest approach is to:

All spoiled food should be put into the trash

Source: Chongqing Tianji Network Co., Ltd.

Source: Science Popularization China, China Youth Network, Voice of the Market

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