Ammonium ferric citrate is a double salt with citrate as anion and ferric ion and ammonium ion as cations. As an anti-caking agent, ammonium ferric citrate can delay the caking of salt by adding an appropriate proportion of ammonium ferric citrate to edible salt.
Before refined salt appeared, the salt people ate was large granular salt, which had good fluidity and was not easy to agglomerate. Later, with the continuous improvement of people's living standards, the food they ate became more and more exquisite. In addition to polished rice, refined powder and essential oil, even salt has become refined salt, and large granular salt is only used when pickling vegetables.
However, the refined salt is easy to absorb the moisture in the air after being opened, and it is easy to agglomerate after being wet, and sometimes it can't be crushed by hand, which is not conducive to daily use. "Today, there is basically no phenomenon of salt caking, because anti-caking agents are added to the salt.
Ammonium ferric citrate is brown or green flake or powder with hygroscopicity. As an anti-caking agent, it is added to salt to prevent salt from caking. According to the National Food Safety Standard Food Additives (GB2760-20 14) issued by the former National Health and Family Planning Commission, in addition to potassium ferrocyanide, sodium ferrocyanide, ammonium ferric citrate, silicon dioxide and calcium silicate can also be added to salt products.
Extended data:
According to China's national standard (GB/T 546 1-20 16), the water-insoluble impurities in salt should not be higher than 0.2%, and to achieve the ideal anti-caking effect, the addition of silica or calcium silicate should reach at least 0.3%, so these two anti-caking agents are not suitable.
In addition, ammonium ferric citrate has also been used as iron fortifier, but its anti-caking effect is not as good as that of potassium ferrocyanide. Only 5 mg of potassium ferrocyanide is needed per kilogram of salt, and 20 mg to 25 mg of ammonium ferric citrate is needed to achieve the same effect. In addition, the salt added with ammonium ferric citrate will appear pale yellow, which is not as easily accepted by consumers as snow-white salt in sense. In terms of cost, ammonium ferric citrate is almost twice as expensive as potassium ferrocyanide.
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