On the morning of June 8, Weibo Big V Ye sent a Weibo about salt. The microblog said that table salt generally contains a "anti-coagulation" chemical substance "potassium ferrocyanide", "decomposes at high temperatures, emits nitrogen, and generates potassium cyanide and iron carbide". It is well known that "potassium cyanide" is highly toxic, and the microblog has spread rapidly. As of 4 p.m. on June 8, there were nearly 18,000 likes alone. The big V also called on everyone to "be careful when buying salt" on Weibo, but followed by a "eat out" question, which made netizens nervous.
△ The picture shows the Weibo posted by Weibo Big V Ye Moumou.
Are there really such toxic chemicals in the salt we eat? The reporter of the Shanghai rumor dispelling platform verified and found that this is an "old rumor". In 2017, the Shanghai rumor-busting platform debunked the rumors on the relevant networks, but the rumors have been spread in the society and have become one of the topics of speculation in various self-media marketing accounts. The search found that in addition to the above Weibo big V's statement that "potassium ferrocyanide will generate potassium cyanide at high temperatures", some public accounts also said that "the amount of table salt containing potassium ferrocyanide in China exceeds 90%", "potassium ferrocyanide is not allowed to be used abroad", "China's excessive addition of potassium ferrocyanide" and so on.
In fact, the above claims are false rumors.
Potassium ferrocyanide is a food additive, also known as yellow blood potassium, the chemical formula is K4 [Fe(CN)6], used in salt production, the main purpose is to prevent salt clumping, and is often used to produce rock salt that is more likely to clump. According to China's "National Standard for Edible Salt" (GB5461-2000), potassium ferrocyanide is a chemical substance that is allowed to be added, and its addition standard is not more than 10 mg per kilogram.
Is potassium ferrocyanide toxic? According to the Joint Expert Committee on Food Additives (JECFA) under the Food and Agriculture Organization of the United Nations and the World Health Organization, according to animal tests, animals have not experienced any adverse reactions when oral doses of potassium ferrocyanide reach 25 mg per kilogram of body weight. On this basis, JECFA used a safety factor of 1000 to set the maximum safety limit for humans, that is, the allowable daily intake (ADI), to 0.025 mg/kg body weight. That is, a 50 kg adult is safe if he eats 1.25 mg of potassium ferrocyanide per day. Usually, the salt purchased by the family is 200 grams / packet, according to the upper limit of the amount of addition, a maximum of only 2 mg of potassium ferrocyanide in a pack of salt. In other words, even if you eat half a pack of salt a day, the intake of potassium ferrocyanide will not exceed the standard.
At the same time, potassium ferrocyanide is not only used in China. The upper limit of potassium ferrocyanide added by the European Union is 20 milligrams per kilogram, which is twice the Chinese standard; the United States allows the use of sodium ferrocyanide (similar in nature to potassium ferrocyanide, the same as the anticoagulant), and the limit is basically the same as in China. The reporter found a brand of british imported salt, which also used sodium ferrocyanide as an anti-coagulant. Therefore, statements such as "only china uses it" and "over-add" are also pure nonsense.
△ In a brand of salt imported from the United Kingdom, sodium ferrocyanide is also used as an anti-coagulant.
In addition, even if vinegar is added, frying and stir-frying do not have to worry about the potassium ferrocyanide in table salt will decompose into hydrocyanic acid and potassium cyanide. Because the binding force of cyanogen and iron in potassium ferrocyanide is very strong and the stability is very high, it takes nearly 400 ° C to decompose to produce potassium cyanide. What is the concept of 400°C? The cooking temperature of the home is generally between 100 ° C and 200 ° C, and the baking temperature is within 250 ° C. After cooking at 400°C, the surface of the non-stick pan may have melted and most of the food is burned.
It is recommended that netizens should not trust and spread this rumor anymore, let alone listen to the "cyanide" discoloration. If you still have concerns about "potassium ferrocyanide", you can also choose lake salt and sea salt without such additives.
Column Editor-in-Chief: Mao Jinwei Text Editor: Mao Jinwei Title Image Source: Visual China Image Editor: Zi Xi