Crazy snacks, but don't forget to pay attention to this thing in the bag

Have you ever noticed that there is a small desiccant in the bag when you eat snacks? When we were young, every time we ate snacks, our parents would always remind us that the small package was not edible because it was poisonous.

So, what are the common desiccants we put in food? Are they really toxic?

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Discuss by situation

At present, we use desiccant or deoxidizer in small packages to keep food fresh. Manufacturers will choose which one to use according to their needs. However, no matter which one is chosen, the manufacturer is to prevent the food from being affected by microorganisms and other factors that affect the shelf life of the food .

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Among these “small packages” that extend the shelf life of food, the one we are most familiar with may be food desiccant.

Because microorganisms reproduce at an alarming rate under certain temperature and humidity. These microorganisms are the culprits for food spoilage and mildew. Therefore, by using food desiccant to reduce the humidity in the food bag, microorganisms have no conditions for reproduction, which can naturally extend the shelf life of the food.

There are two main types of desiccants:

Chemical desiccant

It includes calcium oxide and calcium chloride. Calcium oxide is what we often call quicklime. It does have a strong ability to absorb water, but it will also undergo a violent chemical reaction when it comes into contact with water, releasing a lot of heat. Therefore, with the development of technology, this desiccant has gradually faded out of our daily life .

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Physical desiccant

It is further divided into two types: silica gel and montmorillonite. The main component of silica gel is silicon dioxide, which is absorbed and retained in its own structure through its own fine pore network structure. Moreover, it has another advantage that it can be reused, of course, the price is therefore more expensive .

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Montmorillonite is actually clay, which is more suitable for absorbing moisture in an environment below 50℃. When the temperature is higher than 50℃, the degree of "water release" of clay is greater than the degree of "water absorption". However, clay is cheap and is widely used in food packaging that cannot be sealed with oil or gas.

If desiccants cut off the water source of microorganisms, deoxidizers cut off the oxygen source of microorganisms to prevent them from spreading . At the same time, oxygen may also make oils rancid and give food a bad taste.

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If the deoxidizer wants to turn the sealed food packaging into an almost oxygen-free environment without affecting the original production process of the product, it is necessary to use ingredients that are easy to react with oxygen. At present, there are three types of deoxidizers: iron deoxidizers, sulfite deoxidizers, and organic deoxidizers.

For example, iron-based deoxidizers use the fact that iron is prone to rust in the air, and then use breathable plastic film or wrapping paper to allow it to react with oxygen in the food bag to achieve the deoxidation effect. At the same time, calcium chloride, salt, activated carbon and other ingredients are also added to the iron-based deoxidizer to speed up the reaction.

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In general, the ingredients of deoxidizers are relatively safe, and there is no need to worry too much even if they are not edible.

What happens if you accidentally ingest it?

Common physical desiccants will not cause big problems if ingested accidentally, because they mainly absorb water and do not produce chemical reactions, so they are not harmful to the human body. Just drink more water to promote metabolism.

However, if you accidentally ingest a chemical desiccant, it will be troublesome . Strong alkali can cause serious damage to the gastric mucosa and induce digestive tract perforation, so if you accidentally ingest it, you must seek medical attention as soon as possible.

Although deoxidizers are non-toxic, accidental ingestion may cause acute gastrointestinal reactions such as abdominal distension, intestinal burning sensation, nausea and vomiting. A small number of patients may also experience abnormal liver function.

In short, if you accidentally eat the "independent small package" in the food bag, it is best to seek medical attention in time and listen to the doctor's professional advice. You should still carefully check the food you eat and chew it slowly.

Author: Chen Wen

This article was reviewed by Han Hongwei

This article is produced by the Science Popularization China-Creation Cultivation Program. Please indicate the source when reprinting

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