Sodium Aluminum Sulfate (SAS)

Soda alum, NaAl(SO4)2, supplied in anhydrous and dodecahydrate forms. A slow-acting leavening acid used in self-rising flour and double-acting baking powders, plus a firming and astringent agent in selected pickled-vegetable applications.

White crystalline powder or granular material. Soluble in water; aqueous solution is acidic due to hydrolysis of the aluminum cation.

We supply food-grade Sodium Aluminum Sulfate from manufacturers in China holding ISO, Halal, Kosher and other certifications relevant to the product and production. Aluminum-additive use restrictions in several jurisdictions should be confirmed against the destination market regulations before purchase.

Common market grades include food-grade anhydrous for industrial baking powder, food-grade dodecahydrate for general food and pickling use, and industrial grade for non-food applications. Particle size is specified by baking-powder formulator.

Bulk and reduced-MOQ shipments. Batch-level COA covering assay, aluminum content, neutralizing value, free acid, heavy metals, and microbiology.

Sodium Aluminum Sulfate, commonly called soda alum, has been used as a leavening acid since the late nineteenth century, when aluminum-based leavening systems offered cost advantages over cream of tartar in industrial baking. The product gained widespread commercial use in self-rising flour and double-acting baking powder formulations through the twentieth century.

Production proceeds by reaction of aluminum hydroxide or aluminum sulfate with sodium sulfate under controlled stoichiometry, followed by crystallization. The dodecahydrate is the kinetic product of typical aqueous synthesis; anhydrous material is produced by controlled dehydration.

Regulated in the EU as E521, with use restrictions in several jurisdictions that limit aluminum-containing additives in foods consumed in large quantities by children. JECFA established a Provisional Tolerable Weekly Intake for aluminum from food additives, and several major markets have reduced or eliminated permitted use in specific food categories. Customers should verify current regulatory status against the destination market before specifying SAS in finished-product formulations.

Mechanism as a leavening acid is hydrolysis-driven: the aluminum cation in solution forms acidic hydrated species that react with sodium bicarbonate to release CO2. Reaction is slow at room temperature and accelerates at oven temperatures, making SAS a true heat-activated late-action leavening acid. The slow profile distinguishes SAS from MCP (fast) and SAPP (intermediate), providing the late CO2 burst that sets cake crumb structure during the final phase of baking.

Strategic positioning: SAS is one of three classical leavening-acid options for double-acting systems, alongside SALP and SAPP. The regulatory tightening on aluminum additives has reduced its use in some markets, but it remains a permitted ingredient for industrial baking applications where its kinetic profile is matched to product specification.

• Slow-acting leavening acid in double-acting baking powder formulations
• Self-rising flour and industrial pre-mix baking applications
• Pickling crisp-up agent in selected cucumber and bread-and-butter pickle products
• Astringent in dental and pharmaceutical preparations
• Mordant in dyeing and textile applications outside the food sector
• Water treatment flocculant in some municipal and industrial systems
• Component in fire-suppression chemistry
• Aluminum source in specialty chemical synthesis