Does Fermentation or Distillation Make a Product Gluten-Free?

Published December 9, 2020

Is alcohol gluten-free? When it comes to adult beverages, going for gluten-free beer or spirits can be confusing. Part of the confusion often involves understanding the different processes for crafting beer versus liquor products. If you’re living gluten-free and looking to enjoy a libation, here’s what you need to know.

Starting with Fermentation

Alcoholic beverages typically start with a fermentation process. Fermentation is the conversion of sugars into ethyl alcohol. The fermentation process involves the chemical breakdown of a substance, like a grain or even potatoes. The breakdown happens through the introduction of bacteria, yeasts, or other microorganisms.

Beer most commonly begins with the fermentation of wheat or barley, two gluten-containing grains. Hard liquor can be made from fermented grains like wheat or rye or, in the case of vodka, can also be made from sugar cane or potatoes. If you start with a gluten-containing substance to make alcohol, fermentation might break down some gluten proteins, but the process does not remove all the gluten.

Moving on to Distillation

Distillation takes place through boiling and condensation and can separate particulates in a liquid – like the liquid drawn out of a fermentation process. The fermented liquid is heated up in a still – a large vat with vertical tubes coming out of the top – and with heat, the most volatile compounds become gases that rise to the top, while the less volatile and heavier ones sink to the bottom.

Alcohol is volatile and rises to the top to be syphoned off from the main liquid. Proteins are heavy and gluten proteins are not volatile, so they should sink to the bottom rather than get syphoned off into the distilled liquid. The resulting distilled liquid becomes gluten-free.

Note that an alcoholic beverage could still encounter gluten or traces of gluten after distillation such as whiskey aged in a beer barrel. The safe bet is looking for labeled or certified gluten-free spirits.

Certifying Gluten-Free Distilled Products

In August 2020, the US Food and Drug Administration (FDA) ruled that distilled food products made from gluten-containing grains – rye, barley and wheat – can be labeled as ‘gluten-free.’ Three months later, the Alcohol and Tobacco Tax and Trade Bureau (TTB) came out with an updated ruling on gluten content statements on labeling and advertising of wine, distilled spirits, and malt beverages. The new ruling allows producers to label their distilled spirits as ‘gluten-free’ even if they are made from gluten-containing grains.

The Gluten-Free Certification Organization (GFCO) can certify distilled alcoholic products as gluten-free if they pass through all the steps of its certification process. Beer (and wine) are not distilled alcoholic products. The GFCO’s current position is that any alcoholic beverage derived from gluten-containing grains, but not distilled, cannot be certified gluten-free.

One alcoholic beverage gaining popularity is hard seltzer. Hard seltzer is typically made with cane sugar mixed with water and yeast. In general, a cane sugar-based hard seltzer is gluten-free and can be certified by the GFCO. Another popular alcoholic beverage is the “fermented malt” drink such as a hard lemonade. Fermented malt drinks are not gluten-free, since malt is derived from barley. Note that some hard seltzers use fermented malt instead of cane sugar. Check the ingredients labels carefully on any alcoholic beverage to be sure.

But What About Gluten-Removed Products?

Beer is a product of fermentation and involves yeast breaking down the originating grains, usually wheat or barley. Both wheat and barley contain gluten and should be avoided by anyone living gluten-free and particularly by anyone diagnosed with celiac disease.

Some beer-making companies start with barley, then go through processes to “remove” the gluten proteins that may still be present in the alcohol by-product after the fermentation of the barley. They do this by adding enzymes at the end of the brewing process that break down residual proteins. Adding enzymes to barley beer has been done for decades to prevent the beer from getting cloudy over time, but a secondary effect of the enzymes seems to be a reduction in detectable gluten content.

Unfortunately, it is hard to get an accurate reading on gluten content with the existing tests available. Why? Gluten consists of a number of different protein fragments. Enzymes can break down the specific gluten peptide detected by ELISA (enzyme-linked immunosorbent assay) kits to detect and quantify gluten peptides and proteins.

Most gluten test kits look at, and can identify, one or two of these protein fragments. Currently available (and commonly used) test kits may not see the gluten protein fragments they’re designed to identify because they’ve been broken down by the enzymes. There may still be residual gluten proteins in the tested liquid that can be a problem, particularly for people diagnosed with celiac disease. .

If the “gluten-removed” liquid is put through more powerful testing, such as through a protein analysis process called liquid chromatography-mass spectrometry (LCMS), barley gluten fragments may still be detected.

The Bottom Line

Fermentation doesn’t make a gluten-containing substance gluten-free and the fermentation by-products will still contain gluten fragments. Distillation can purify the alcohol by-product, and the FDA, TTB and GFCO recognize that distilled alcohol may be gluten-free (as long as no gluten-containing flavorings or additives are added after this distillation process). Adding enzymes to barley-based beers can break down the most commonly detected gluten proteins and peptides in the fermented liquid, however, stronger testing processes may still detect barley glutens in gluten-removed products.

If you are living gluten-free, and particularly if you have a diagnosis of a sensitivity, celiac disease, or a wheat allergy, take careful note of the labels on fermented and distilled alcoholic beverages. As time goes on, you may see the official new GFCO mark on more distilled beverages. When in doubt, err on the side of caution.