E536 - Kaliumferrocyanid

Origin

Potassium ferrocyanide is a synthetic compound produced by reacting hydrogen cyanide with ferrous chloride and then treating it with calcium hydroxide. The resulting calcium ferrocyanide is then reacted with potassium carbonate to yield potassium ferrocyanide. It is a coordination complex, meaning that the cyanide ions are tightly bound to the iron atom, making it stable and non-toxic under normal conditions.

Usage

E536, potassium ferrocyanide, is primarily used as an anticaking agent in table salt. It prevents the formation of lumps and ensures that the salt remains free-flowing. The permitted levels are strictly regulated to ensure consumer safety. It is also used in the production of citric acid and wine. The levels used in salt are very low, typically up to 20 mg/kg.

Side Effects

Potassium ferrocyanide is considered safe for consumption in the small quantities used in food. The cyanide is strongly bound to the iron atom and is not readily released. However, at very high temperatures (above 300°C), it can decompose and release toxic hydrogen cyanide gas. This is not a concern in normal food preparation or consumption. Regulatory bodies such as EFSA and the FDA have evaluated its safety and have established acceptable daily intake (ADI) levels. There are no known significant side effects associated with its use as an anticaking agent at permitted levels. The ADI is not specified, meaning that at the levels used in food, it does not represent a health concern.

Regulatory Status

Potassium ferrocyanide (E536) is approved for use as a food additive in many countries, including the European Union and the United States. The European Food Safety Authority (EFSA) has evaluated its safety and has set specific limits for its use in food products. In the United States, the Food and Drug Administration (FDA) permits its use as an anticaking agent in salt under specific conditions outlined in the Code of Federal Regulations (CFR).