E904

E904 is the food additive designation for shellac, a natural resin secreted by lac insects. The resin is produced by female lac insects, primarily Kerria lacca, on host trees in parts of Asia. After collection, the lac resin is purified and processed into edible shellac that can be used as a glaze or coating.

Shellac forms a hard, glossy film when applied to foods or pharmaceutical tablets. It is hydrophobic and dissolves in certain solvents, notably alcohols, which allows it to form edible coatings that are resistant to moisture and gas to some extent. Common uses include glazing confectionery, candies, chocolates, and the protective coating on tablets and capsules.

Regulatory status and safety: E904 is approved as a glazing and coating agent in many jurisdictions, including the European Union, where it is listed as a permitted food additive. It is typically used in small amounts and must be labeled when present. In pharmaceuticals, shellac coatings are used for enteric or controlled-release purposes on some medicines. Potential allergies or sensitivities to lac-derived products exist, though such cases are rare.

Notes: Shellac coatings can be bleached or color-adjusted during processing, resulting in a range of appearances from clear to amber. As a natural resin, shellac serves as an alternative to some synthetic film-forming coatings in both the food and pharmaceutical industries.