Shellac is a resin secreted by the female lac bug, on trees in the forests of India and Thailand. It is processed and sold as dry flakes (pictured at right), which are dissolved in ethanol to make liquid shellac, which is used as a brush-on colorant, food glaze and wood finish.
Many people may not be aware that the glaze that covers some of their favorite products – including vitamins, pharmaceuticals, candy and even some fruit – may actually be made from shellac; a resin from the secretions of the female lac insect.
When used in food and confections, shellac has the food additive number E904, and is described on food labels as ‘confectioner’s glaze’, ‘confectioner’s resin’, ‘resinous glaze’, ‘candy glaze’, ‘pure food glaze’ and ‘natural glaze’.
Is there a vegan alternative to shellac? Of course! Zein, a corn protein, is a competitive non-animal-based product. Pure zein is clear, odorless, tasteless, hard, water-insoluble, and edible. It is already used as a coating for candy, nuts, fruit, pills, and other encapsulated foods and drugs. In the United States, it may also be labeled as ‘confectioner’s glaze’. NOTE: As well as sometimes being made from shellac, confectioner’s glaze can also contain beeswax.
I couldn't find a source for consumers for a Zein based Confectioner's glaze.