E523 – Aluminium ammonium sulfate

Description

White crystalline solid or powder

Risks

Notes

Aluminium ammonium sulfate, commonly known as alum, is a white crystalline mineral compound that combines aluminum, ammonium, and sulfur with oxygen. It can be found naturally in certain rock formations, but the food-grade version is typically produced synthetically by combining aluminum sulfate with ammonium sulfate in controlled laboratory conditions. The resulting white, odorless crystals dissolve easily in water. In food production, E523 works as a firming agent, helping to maintain the crisp texture and structural integrity of processed foods. You'll most commonly find it in pickled vegetables, where it keeps cucumbers crunchy in pickle jars, and in some baked goods where it helps maintain texture. It's also used in certain canned vegetables to prevent them from becoming mushy during the preservation process. This additive is synthetic rather than naturally extracted, and it's generally suitable for vegetarian and vegan diets since it contains no animal-derived ingredients. However, it's worth noting that some people prefer to avoid aluminum-containing additives, though regulatory agencies consider E523 safe for consumption at approved levels. It's approved for use in most countries, including the EU and US, with specific limits on how much can be used in different food categories.