There’s a trend in vodka that I’ve noticed over the past few years: multiple distillations, i.e., repeating the process of distillation, of heating and collecting the condensate and repeating 4, 5, or 6 times.
Spirit manufacturers often claim that, due to marked reduction in gluten proteins with the process of a single distillation, vodka, whiskey, bourbon, gin, etc. are virtually gluten-free, though most have not pursued applying this formal designation that FDA regulations established as having to contain less than 20 parts per million gluten. The Federal Alcohol and Tobacco Tax and Trade Bureau also does not permit a gluten-free label to be affixed to a spirit if it was originally brewed from a gluten-containing grain, such that no vodka brewed from wheat can be designated gluten-free. The Trade Bureau does, however, allow designations such as “processed,” “treated,” or “crafted” to remove gluten.
Just as water can be distilled to remove both dissolved and suspended impurities, the separation of the various components of a liquor means that the protein residues, i.e., gluten and others, are left behind, separated from the alcohol and the components that confer flavor. (Vodka purists sometimes claim that multiple distillations also reduce the flavor and uniqueness of a vodka, but our first concern here is safety.) Anecdotally, however, many of us have reacted to such presumptively gluten-free spirits subjected to single distillations.
Enter multiple distillations. In multiple distillations, the product of the first pass of distillation is again subjected to the heating/condensing of a second distillation process. The process is then repeated for as many cycles as desired.
My first encounter with a multiply-distilled product was Tito’s vodka that has been distilled 6 times. Although brewed from corn and thereby potentially containing zein protein residues, I have had an occasional martini made with Tito’s and have never reacted. (My reactions involve virtually immediate gastrointestinal turmoil.) Of course, don’t be confused by the claim made by manufacturers who make the mistake of claiming that, because it is not brewed with gluten-containing grains wheat, rye, or barley, it must therefore be gluten-free—spirits brewed from corn are indeed gluten-free but not free of the closely-related “prolamin” protein of corn, zein, that overlaps in many effects with gluten (actually gliadin, the prolamin protein of wheat, rye, and barley). But it means that Tito’s, distilled 6 times starting with a mash that certainly contains plentiful zein proteins, likely has little to none in the final product.
I put the multiple distillation idea to the ultimate personal test: I made martinis with Costco’s vodka brewed from wheat and distilled 6 times. Besides being surprisingly smooth for a very low-cost product, I had no reactions. And this has held true over several more martinis over the months.
I know of no formal testing to prove the proposition that multiple distillations reduce gliadin/gluten/prolamin protein content to negligible levels, but it does make sense when you think about the process of distillation. I believe it means that multiple distillations of even a vodka brewed from wheat may be safe. But what is the minimum number of distillations required to achieve this–3, 4, 5, 6? I don’t know, but I believe that the greater the number of distillations, the more assured you can be that you will not react.
Vodka choices, even singly-distilled, but brewed from non-grain sources include brands brewed from grape (Ciroc, Trader Joe’s Versatile Spirit) and potato (Chopin, Luksusowa Red Label, Monopolowa, Boyd & Blair, Cold River, Blue Ice), and sugar cane (Ocean, Cane). But we expand the list with multiply-distilled choices brewed from grains:
Tito’s—distilled 6 times from corn
Costco vodka—distilled 6 times from wheat and grains
New Amsterdam—distilled 5 times from wheat and grains
Skyy—distilled 4 times from wheat and grains
Belvedere—distilled 4 times from rye
Please feel free to share your finds from the multiply-distilled vodka world, as well as your taste and health reactions.