Wheyskey, anyone? Or perhaps some Cowcohol?
It’s not the most obvious ingredient for spirits, but distilling with whey—the watery liquid left once curds have formed from milk, a key step in the cheesemaking process—is a more established practice than many people realize.
A variety of whey-based spirits have been appearing in recent years on store shelves and in online shops, from vodka to aquavit to, yes, Wheyskey, a barrel-aged spirit from Oregon-based brand Wheyward Spirit. While some small distilleries in Europe and Down Under have been using whey over the past several years, it appears to be only recently catching on in the United States.
Besides being a distinctive, attention-getting product, a major hook for whey spirits is that they use what is often a waste product. Whey also imparts some unique characteristics to a spirit, including a slight sweetness and creamier mouthfeel.
Of course, it’s not as simple as fermenting and distilling it. Even if there’s no lactose left in the finished spirit, its presence in the whey base presents a challenge to distillers. Depending on your location, finding it may not be easy, either.
The Hard Whey
First, you need the proper form of whey—preferably already concentrated and filtered, after being used to make cheese or other dairy products. At Copper Crow Distillery in Bayfield, Wisconsin, they use whey sourced from Burnett Dairy, a farmer-owned cooperative that makes cheese.
As is typical for dairy companies, Burnett uses a reverse-osmosis membrane system to concentrate and filter the whey because the proteins are a valuable by-product—not so valuable, however, to distillers.
Protein in your whey is bad news for making spirits, says Stephen Nold, a microbiology professor at the University of Wisconsin–Stout. “When you get concentrated cheese whey, the lactose concentration is going to be about 20 percent, and filtration is going to get rid of the protein,” he says. In his view, you don’t want that protein in the system because putting it through the still can cause a goopy mess and a clean-up headache.
Copper Crow owner Curt Basina says the company that sells them the concentrated whey also pasteurizes it, giving it a shelf life of about 30 days. “It gives us some time to play around with it before it possibly becomes infected by other bacteria we don’t want,” he says. “Play around with it, have fun with it. But do your best to find a source that already has the proteins removed.”
Once you have the right whey, Nold says, it isn’t too difficult to produce the spirit once you understand a few key steps:
- First, drop the pH to between 5 and 5.5 to inhibit bacteria; at Copper Crow, Basina says they drop it to 5.0 using citric acid.
- Next, add lactase—the same enzyme that helps our bodies digest milk. In our bodies or in the fermentor, it breaks the lactose down into constituent sugars—galactose and glucose—that can be fermented by Saccharomyces cerevisiae.
- Then, pitch the yeast. Nold says that while testing whey-spirit production with Basina, they tried all sorts of strains, and Red Star’s distiller’s active dry yeast is what worked best for them.
After fermenting for about a week at room temperature, Nold says, you can get a base of 8 or 9 percent alcohol, which can then be distilled. Copper Crow Whey Vodka is bottled at 80 proof, 40 percent ABV, and retails for $30 per 375 ml bottle.
Making “Cowcohol”
While it’s still early days for whey spirits, they’re not limited to the country’s biggest dairy state, nor is there only one way to produce them. In Canby, Oregon, just south of Portland, TMK Creamery and Distillery has arrived at a method that has some surprising differences from Copper Crow’s.
TMK is a first-generation dairy farm that became a creamery; owner Todd Koch was milking cows, making cheese, and making ice cream. He heard that Oregon State University in Corvallis was researching the fermentation and distillation of whey, partly to avoid waste and environmentally damaging disposal.
Koch had no background in brewing or distilling before learning more from Paul Hughes, a distillation scientist at OSU. Koch thought it “would be cool if my cows could make spirits.”
Unlike Basina at Copper Crow, Koch keeps the protein in his whey—but he also ferments it differently, using Kluyveromyces marxianus. This yeast is known for its ability to ferment lactose (among other things) so the dairy industry often uses it to turn excess whey into biofuel.
To distill his fermented whey, Koch custom-built a continuous still that can manage the lipids and proteins without too much mess. “As long as it has fermented whey, it would run and avoid scorching, generating steam,” Koch says. “We’re doing an indirect heat distillation using steam. The challenge we had initially—and we had a lot of trial and error—beginning in 2019, we ran into a lot of problems with the lipids and proteins. There are different ways to filter that stuff out, but we are relatively small scale, like 15,000 to 20,000 bottles a year.”
For Koch, the custom still made more sense than filtering the whey to remove the protein. The continuous distillation gets his whey-based spirit up to 192 proof, the azeotrope maximum. Then Koch cuts it down to 80 proof for his Cowcohol Vodka, which sells for $39.99 per 375 ml bottle.
“Two things for us made sense and made it a no-brainer,” he says. “It’s more environmentally friendly to dispose of the whey and create another retail product with an ingredient we start with—milk. Any time you can add another product, you’re becoming more efficient and doing a better job environmentally.”
Why Whey?
Besides the attraction of using a possible food-waste product to make an unusual spirit, there is another appealing point: Whey is pretty cheap, so a craft spirit made from it can go for a relatively high margin. Copper Crow buys its whey for about $100 per 1,000 liters. For TMK, it’s a by-product of their own dairy farming.
For both Basina and Koch, another motivation is environmental. While the proteins in whey are worth something once separated, much of the liquid still goes to waste. It can supplement animal feed to an extent, and farmers can spread it on fields up to a certain saturation point. But it’s not good for wastewater treatment, killing bugs that decompose human waste. Even spraying it on fields can cause problems if it leeches into a stream because it depletes oxygen that other organisms need.
Finally, in the view of the distillers who’ve made them, whey spirits just taste good. There are some accolades to back that up, too, with Wheyward Spirit winning double gold at the New York World Wine and Spirits Competition in 2021.
Copper Crow has about a dozen SKUs, and half are made from whey, including a vodka, gin, starka, and amaretto. Basina plans to produce cocktail bitters with whey spirits as a base, and he says he is excited about other industries using whey for other products.
“I think we’re just at the very tip of the iceberg as far as the distillation is concerned,” Basina says. “We’re just touching the very, very tip of what is possible to be able to ferment and distill whey and turn it into spirits.”