Aluminium sodium sulphate

Aluminium sodium sulphate — a form of sodium alum — is a double sulphate salt containing both aluminium and sodium. Historically, it was used as a component in baking powders (as sodium aluminium sulphate or SAS), providing a delayed acid reaction during baking that resulted in good oven spring and consistent bread texture. It is also used as a firming agent and pickling aid for vegetables, maintaining textural integrity in acidified products.

JECFA reviewed aluminium sodium sulphate in 2006 alongside other aluminium-containing food additives and determined that an ADI could not be allocated. This "not allocated" classification reflects insufficient data to quantify a safe upper intake, combined with general concern about cumulative aluminium burden from all dietary sources. Aluminium from aluminium salts is bioavailable, and repeated dietary exposure contributes to the body's total aluminium load, which accumulates particularly in bone and brain tissue over time.

Aluminium sodium sulphate is permitted in the EU for use in specific applications at regulated maximum levels, with controls designed to limit aggregate aluminium intake from food. EFSA continues to monitor total aluminium intake across European populations, with baked goods made with aluminium-containing leavening agents identified as a significant contributor to dietary aluminium for regular consumers. Home bakers who wish to minimise aluminium in their baked goods can choose aluminium-free baking powder formulations based on monocalcium phosphate, cream of tartar, or sodium acid pyrophosphate, which are widely available.