Distilled spirits like whisky, gin and vodka are gluten-free even though they are made from gluten-containing grains such as wheat, rye and barley.
The process of alcohol distillation removes all protein, including gluten. This means that people with celiac disease can enjoy distilled spirits if they are sure gluten-containing ingredients have not been added after distillation. This is done with liquors like ouzo and flavoured vodkas, which may no longer be gluten-free after enrichment with different ingredients.
The Alcohol and Tobacco Tax and Trade Bureau (TTB) in the US in 2020 revised its policy to allow labels and advertisements of spirits distilled from wheat and other gluten-containing grains to use the term “gluten-free”. It stressed that maintaining good manufacturing practices is key to ensuring gluten-containing material would not be present in the final product.