Soy sauce is 'harmful oil', not only toxic but also carcinogenic? Is soy sauce still edible? tell you the truth

"Did you know? There are carcinogens in soy sauce!"

"What's going on? I haven't heard of it before."

"The Hong Kong Consumer Council found that 11 types of soy sauce contained carcinogens during a random inspection. This is too scary."

"My mom even asked me to buy a box of soy sauce during Double Eleven last time... I'm a bit afraid to eat it now"

“……”

Basically, every household may need to use soy sauce for seasoning when cooking. However, in recent years, there has been an endless stream of sayings that "soy sauce is harmful oil". More and more people are worried that soy sauce is really a health hazard. Does soy sauce really cause cancer? Will it be harmful to the human body?

1. Soy sauce was found to be a carcinogen, can it still be eaten?

In the sampling inspection of soy sauce, the carcinogen detected was 4-methylimidazole, which may cause cancer in humans.

The reason why 4-methylimidazole appears in soy sauce is mainly from the caramel pigment added in soy sauce. Caramel coloring can make soy sauce look dark brown, which can be divided into two types: natural and synthetic.

Among them, the natural caramel pigment mainly refers to the fried sugar color when cooking. The synthetic caramel color refers to a by-product produced during the production process, including 4-methylimidazole .

As for the carcinogenicity of 4-methylimidazole, international authoritative organizations also believe that the safety of 4-methylimidazole is still very good.

The International Agency for Research on Cancer (IARC) under the World Health Organization (WHO) lists 4-methylimidazole as a 2B carcinogen, that is, there is clear evidence that it can cause cancer in animals, but there is no evidence that it is carcinogenic to humans .

In China, there are strict controls on the limit value of 4-methylimidazole in caramel coloring.

According to the "National Food Safety Standard Food Additive Caramel Color", the limit value of 4-methylimidazole in caramel coloring added to food is 200mg/kg, that is, the content of 4-methylimidazole per kilogram of soy sauce cannot exceed 200mg.

The daily intake of 4-methylimidazole allowed by the human body is less than 0.04 mg, calculated on the basis of a 60-kg adult, the daily intake of 4-methylimidazole should be less than 2.4 mg .

Among the soy sauces checked, the highest content of 4-methylimidazole is only 6mg/kg , which is equivalent to 0.03mg of 4-methylimidazole intake based on the calculation of using about 5ml of soy sauce each time, which is far lower than the human body Allowable Daily Intake.

So what if you really don't want to buy soy sauce containing 4-methylimidazole?

First of all, buy soy sauce produced by a regular big brand, and choose one that does not contain caramel coloring in the ingredient list.

Secondly, try to choose light soy sauce, because light soy sauce is mainly for seasoning, and many of them do not add caramel pigments , while the main function of dark soy sauce is to improve color, and more caramel pigments are usually added.

2. If you eat too much soy sauce, will your skin turn black?

It is said that eating too much soy sauce will cause the skin to darken. Is this statement true or false?

First of all, let us understand how the skin turns black. A person's skin tone can be influenced by factors such as genetics, carotenoids, hemoglobin status, and more. Among acquired factors, the most important factor affecting skin color is the production of melanin.

When the skin produces more melanin, the skin color will become darker, otherwise it will appear whiter. The common factors that stimulate the production of melanin include sun exposure, estrogen, melanotropin and progesterone, so it has nothing to do with whether you eat soy sauce or not.

If you have scars on your body, will the scars be darker if you eat soy sauce? The answer is no, whether it is soy sauce or other foods that contain natural or artificial colors, it will not affect the color of scars.

Wound healing is mainly related to the metabolism of the skin. In the process of skin repair, fibroblasts are mainly responsible. When a local inflammatory response occurs, fibroblast proliferation is stimulated to promote wound healing.

At the same time, inflammation will also stimulate pigment cells and make their functions active, so more melanin will be produced, causing pigmentation, so the wound will look darker than the surrounding skin. After the wound heals, it will become "black." " will gradually fade away .

3. Prepared soy sauce VS brewed soy sauce, which one to buy?

Soy sauce on the market can be divided into two types: prepared soy sauce and brewed soy sauce.

Brewed soy sauce refers to the soy sauce made from soybeans as the main raw material, adding a small amount of wheat flour, rice husk or bran and other raw materials, and undergoing natural fermentation and other processes . Due to the large geographical environment during the fermentation process, so different Soy sauce produced in each region has its own characteristics.

Formulated soy sauce is based on brewing soy sauce, adding acid hydrolyzed vegetable protein pulp and a small amount of food additives to make soy sauce. There is no natural fermentation in the production process, and the production process is relatively simple and time-consuming.

It should be noted that there are certain health risks in the preparation of soy sauce.

Since brewed soy sauce will be diluted in the preparation of soy sauce, its nutritional value will be lower than that of brewed soy sauce. In addition, during the production process, chloropropanols may exceed the standard in the preparation of soy sauce . These chloropropanol compounds have certain toxicity, mutagenicity and carcinogenicity to the liver, kidneys, blood circulation and nervous system of the human body.

How to choose a good soy sauce? Mainly look at 3 indicators:

• Amino nitrogen

When purchasing soy sauce, the first thing to look at is its amino acid nitrogen content, which is the key to determining the quality of soy sauce. Generally speaking, the higher the amino acid nitrogen content in soy sauce, the higher the quality of the soy sauce and the stronger the umami taste.

Because the length of soy sauce brewing time will affect the amino acid ammonia content, the ammonia nitrogen content in soy sauce brewed for 180 days is about 1.1g/100ml, and the ammonia nitrogen content in soy sauce brewed for 380 days is about 1.2g/100ml.

The content of amino acid nitrogen in qualified soy sauce should not be lower than 0.4g/100ml; if the content of amino acid nitrogen reaches more than 0.8g/100ml, it is a special grade soy sauce.

• accompaniment or cooking

When purchasing soy sauce, it is necessary to distinguish the main purpose. Light soy sauce is mainly used to accompany meals and can be eaten raw, such as cold salad or dipping, so the requirements for hygienic quality will be relatively high during production.

Dark soy sauce is mainly used for cooking, such as cooking braised pork and other dishes, which need to be heated before eating, and the requirements for hygienic quality will be lower. If you always use the same bottle of soy sauce, it is recommended to try to choose light soy sauce for meals .

• sodium content

The level of sodium content in soy sauce is also an important indicator to identify the quality of soy sauce. When choosing soy sauce, try to choose ones with lower sodium content among similar units , and avoid high sodium content. A spoonful (10 ml) of soy sauce contains about 1.5-2 grams of salt, and according to the recommendations of the World Health Organization, the daily salt intake of adults should be controlled within 5 grams.

Therefore, it is recommended not to pour directly from the bottle when seasoning with soy sauce, as it is easy to pour too much with shaking hands, and it is better to control the amount of soy sauce when adding soy sauce with a spoon.

Soy sauce is a very common condiment. Generally speaking, as long as you buy a regular brand of soy sauce, you don't have to worry about carcinogens. When purchasing soy sauce, for the sake of health, try to buy brewed soy sauce with high amino acid nitrogen content and low sodium content.

References:

[1] Comparative test of 21 types of soy sauce: 11 types detected trace amounts of possible carcinogens. Consumer Reports. 2017-01-14

[2] Zhang Jingbo. Eating soy sauce will make the wound turn black. China Consumer News. 2006-08-02

[3] Choose soy sauce brewing or preparation? .Guangzhou Daily.2016-09-01

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