Other names for the additive (synonyms)
General Information
Additive E500(iii) — sodium carbonate and bicarbonate mixture is a subtype of the group of food additives E500, commonly known as "soda". In technical literature, this substance is often referred to as sodium sesquicarbonate or soda salt.
Chemically, the additive is a crystalline hydrate with the composition Na₂CO₃ · NaHCO₃ · 2H₂O — a double salt of carbonic acid containing both sodium carbonate and sodium bicarbonate in a 1:1 ratio with two water molecules.
In industry, sodium sesquicarbonate is produced by evaporating natural mineral brines (trona, nahcolite) or by controlled blending of sodium carbonate and sodium bicarbonate in aqueous solutions followed by crystallization.
In terms of properties, additive E500(iii) is a white crystalline powder that dissolves well in water, creating a slightly alkaline solution. When heated, sodium sesquicarbonate releases CO₂, although this process is less intense than with pure sodium bicarbonate.
In the food industry, additive E500(iii) is used as:
- an acidity regulator and buffer for maintaining stable pH levels;
- an auxiliary component of dough leavening agents;
- an anti-caking agent in dry mixes;
- a texture stabilizer in confectionery products.
The sodium carbonate and bicarbonate mixture is less commonly used in the food sector compared to baking soda (E500(ii)), but it is added to specialized formulations where a gentler regulation of the acid-base balance is required.
Read more about sodium carbonates and their effects on the human body in the main article about additive E500.