E573 - Aluminium stearate

Origin

Aluminium stearate is a metallic soap derived from the reaction of stearic acid (a naturally occurring fatty acid) with an aluminium salt, typically aluminium chloride or aluminium sulfate. Stearic acid can be sourced from both animal and vegetable fats. The specific origin of the stearic acid used to produce aluminium stearate is often not specified, making it difficult to ascertain its precise source without detailed product information from the manufacturer.

Usage

In the food industry, aluminium stearate functions primarily as an anti-caking agent, lubricant, and release agent. It is used in powdered food products to prevent clumping and ensure free flow. It can also be found in some confectionery items and chewing gum. Beyond food, aluminium stearate has applications in pharmaceuticals, cosmetics (e.g., as a thickening agent in lotions and creams), and industrial products like paints and greases. Its hydrophobic properties make it useful in water-repellent coatings.

Side Effects

The safety of aluminium stearate has been evaluated by various regulatory bodies. Concerns primarily revolve around the potential for aluminium accumulation in the body, which has been linked to neurotoxicity and bone disorders in high concentrations. However, the levels of aluminium stearate used in food are generally considered safe for most individuals. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has established an Acceptable Daily Intake (ADI) for aluminium from all sources. It's important to note that individuals with kidney problems may be more susceptible to aluminium accumulation. Allergic reactions to aluminium stearate are rare but possible. More research is continuously being conducted to further assess the long-term effects of aluminium exposure from food additives.