E509, also known as calcium chloride, is a food additive widely used in the food industry as a firming and stabilizing agent, as well as for regulating the acidity of products.
Calcium chloride is often used in cheese production, canning, dairy processing, and winemaking.
While calcium chloride is considered safe for consumption in reasonable amounts, an excess of this additive can cause some unwanted side effects, such as gas, diarrhea, or nausea.