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A New Perennial Favorite: Making Whiskey with Kernza

There are costs and challenges—and it’s not all that easy to find—but a growing handful of distillers are excited about the potential of Kernza, a perennial grain domesticated for its environmental benefits.

Courtney Iseman Jan 2, 2024 - 14 min read

A New Perennial Favorite: Making Whiskey with Kernza Primary Image

Courtesy Sustain-A-Grain

Whiskey isn’t whiskey without grain, but what does the future of grain agriculture—and, therefore, whiskey production—look like in the face of climate change? Are there paths forward to make growing grains for spirits more sustainable, responsible, and efficient?

Those are the kinds of questions that The Land Institute, a nonprofit research group based in Salina, Kansas, is answering with a perennial grain called Kernza. Already, a handful of North American distillers are seizing the opportunity to see what Kernza can bring to their whiskeys and to their own sustainability measures.

What Is Kernza?

Founded by Wes and Dana Jackson in 1976, The Land Institute’s mission is to develop more natural, sustainable agriculture by domesticating perennial crops. While most grains can grow for only one season until harvest, perennials can be productive for years. That’s the case with Kernza, an intermediate wheatgrass that The Land Institute developed to have higher yields than other perennials.

“The goal of The Land Institute is to replace annual agriculture as a whole,” says Tessa Peters, the group’s director of crop stewardship.

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For barley and other traditional grains, farmers need to reseed every year. This conventional system of farming can lead to soil erosion, nutrient pollution via nitrogen fertilizers, and the depletion of groundwater resources. With grains such as Kernza, The Land Institute is working to promote a more natural, prairie-like system that is less intensive and does not require reseeding.

“The idea of having perennials on the landscape,” Peters says, “is they have living roots in the soil, holding the soil in place and reducing soil erosion, increasing water filtration and improving water quality and soil structure and health.”

Most farmers plant Kernza in the late summer or early fall, she says. “The first fall, it grows and gets established. It goes dormant in the winter, and in the following spring it comes out of dormancy, continuing to grow and producing a good amount of biomass. In June, it will flower. The grain ripens, and then farmers are able to harvest it between mid- to late June or even as late as August, depending on where they are.”

Farmers can do this without having to replant for three to four years. Growers who have animals can keep the plant in place for up to six years, using Kernza for feed or forage.

For distillers interested in experimenting, Kernza offers some distinctive flavors that may be of interest—more about that below. More broadly, however, it should appeal to any distilleries looking for ways to demonstrate environmental responsibility and to appeal to customers who are looking for the same.

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Sourcing Kernza

Kernza has captured the interest of some distillers as well as brewers, helping to bring attention to the sustainability benefits and raise consumer interest. However, there are challenges to working with the grain—and the first of those is its price.

At Tattersall Distilling in Minneapolis, for example, head distiller Bentley Gillman cites a price tag of $5 to $6 per pound, compared to about 50 cents for more typical grains. However, that cost is declining as more growers take on Kernza, since there is more demand from buyers in various industries. For them, the benefits outweigh the obstacles.

Because it’s still early days for Kernza, some distilleries (including Tattersall) get it by working directly with The Land Institute or with partner organizations. At Denver Distillery, head distiller Chris Anderson-Tarver says they get it through the U.S. Department of Agriculture (USDA), which is facilitating various Kernza partnerships while working on guidelines for growing, selling, and using the grain.

At Smoky Valley Distillery in Marquette, Kansas, cofounder Stan Von Strohe says they get their Kernza from Sustain-A-Grain in nearby Moundridge, Kansas. Sustain-A-Grain has been growing Kernza in collaboration with The Land Institute for five years, meanwhile trying to raise interest among more growers and producers.

Some of those growers are in Minnesota. Greg Lancette, cofounder and master distiller at Revive Distilling—which launched about a year ago with a claim to being the state’s first carbon-negative distillery—says he’s fortunate to be located near farmers who grow Kernza and a local supplier who sells it.

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For most distillers, it may not be quite that easy to find. “The U.S.A. has 80 million acres of corn grown each year,” Lancette says. “Kernza has 4,000 acres worldwide.”

However, organizations such as The Land Institute and Sustain-A-Grain are happy to help connect distillers with growers—and that pool of growers is expanding, which should lead to lower prices and a more reliable supply chain. In fact, Von Strohe at Smoky Valley is about to dramatically slash the distance their Kernza will need to travel: They’ll plant their own this spring, and he says that in two years he should have enough to distill.

Peters says the grain’s footprint is growing: “Over the last five years, we’ve gone from having really only two production regions—the Upper Midwest in Minnesota and a little bit in Wisconsin, and also a little bit in Kansas—to having growers in 25 states.” Plus, Canada, France, Germany, and Sweden are among the countries where growers have expressed interest in planting.

Distilling with Kernza

When Denver Distillery got its Kernza supply through the USDA, Anderson-Tarver says, it arrived pre-milled. That was fortuitous because milling the grain is one of the challenges of working with it—though that has yet to scare away interested distillers, brewers, or other buyers.

Kernza’s small size requires precise milling—a Kernza kernel is about one-fifth the size of a regular wheat kernel. This takes some planning. Tattersall, Gillman says, had theirs milled off site. At Revive, Lancette says they are lucky enough to have a hammer mill at their disposal.

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“The grain is ground into a fine flour instead of just cracked,” Lancette says. “This way, we have access to the whole grain structure. If you have a roller mill, most likely you will have to have someone else mill the grain for you. It is too small for the rollers and will fall right through, thus not allowing you to get the starch conversion you need.”

Like most distillers who are using it, Lancette is working with unmalted Kernza. Besides flavor, starch conversion and available enzymes are factors to weigh when deciding whether to attempt a 100-percent Kernza mash or to blend it with more conventional grains.

Tattersall’s Kernza Perennial Grain Whiskey, released in April 2023, was indeed distilled from a mash of 100 percent Kernza. Gillman says they used about 1,000 pounds of Kernza per cook, getting about two barrels of whiskey from their 850-gallon cooker. They added exogenous enzymes—alpha amylase, beta glucanase, and a glucoamylase—to aid in the conversion. Smoky Valley’s Kernza Whiskey, meanwhile, includes both corn and malted barley in the mash.

At Denver Distillery, Anderson-Tarver says they were excited to see what flavors Kernza would bring to the table, so they knew they wanted it to be more than half the mash bill. To figure out the exact proportion, the team worked backward through the problem.

“A couple of places have published nutritional information on Kernza, which is helpful, but we don’t fully know the proteins and starches we’re dealing with,” Anderson-Tarver says. “Being [a domesticated] intermediate wheatgrass, we think of it as similar to rye or wheat.”

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They factored in the size of their fermentors and how much Kernza they had on hand; they also typically avoid using exogenous enzymes, so they knew that some malted barley would be necessary to help ensure conversion. They ended up at 75 percent Kernza and 25 percent malt, and they also added enzymes to aid conversion as “essentially insurance for us,” Anderson-Tarver says, “since there was no published data that I could find on starch content for Kernza.” He says that they’ll keep playing around with the ratio as they perfect their recipe.

At Revive, Lancette says they also aimed for that benchmark of 51 percent or more. “We wanted to be able to put the Kernza name front and center on the bottle so had to get to that number,” he says. They ended up with 29 percent malted oats plus equal portions of millet and sorghum; Lancette says they also chose those grains based on environmental factors. “All three are low-water crops, drought-tolerant, and can handle heat well.”

His advice for distillers who want to avoid using enzymes, however, is to add 10 to 15 percent malted barley to the grain bill. While Lancette is planning to produce a 100 percent Kernza whiskey—they like its unique, subtle flavor—he says it’s an expensive endeavor. “We wanted to get some barrels filled first and make sure our flavors were spot on,” he says.

Beyond the grain bill and consideration of enzymes, there’s not necessarily anything in the mashing process that needs to be adjusted for Kernza. “We treated [our Kernza whiskey] very similar to our wheat whiskeys,” Lancette says. “Mash temperature and time are similar; we mash at 150°F [66°C].”

Anderson-Tarver’s recommendation is to consider your equipment. “Anyone who knows their way around grain-heavy mashes knows to pay attention to whether their equipment can actually handle it,” he says. He added rice hulls to aid the lauter; how much water to add is something else to monitor.

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The Flavors and Future of Kernza

Flavor-wise, growers and distillers say that Kernza isn’t entirely like any other grain.

In taste tests, Peters at The Land Institute says, people describe it as nutty or sometimes a bit grassy; for her part, she finds some graham cracker–like notes.

Tattersall’s Gillman says it has similarities to wheat, but it does have that nuttiness plus a “light, almost maple syrup–like sweetness.”

Von Strohe at Smoky Valley says that he finds Kernza strikes a balance between bourbon and rye—not quite as sweet as the former, nor as spicy as the latter, but still a bit sweet and slightly spicy. Revive’s Lancette notes a bready character along with notes like baking spices.

Those flavors can also diverge depending on a distillery’s approach to using Kernza. Anderson-Tarver says Denver Distillery’s Kernza whiskey has a jammier quality than the stone fruit–like notes they’re used to getting from their yeast. “There is a Fig Newton, golden raisin flavor we’re extremely excited about,” he says.

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Unlike bourbon, for example, Kernza whiskey is new enough that there are no real restrictions on how to produce it—for example, there are no parameters on barrel types, aging periods, or strengths. This provides room for experimentation and creativity.

“We knew we wanted to age it,” Anderson-Tarver says. “We thought it might be a softer whiskey, and pretty nuanced, so we used second-fill barrels because there’s no rule that says the barrels have to be virgin.” They used spent rye whiskey barrels, getting a bit of spicy rye character to accentuate the Kernza profile.

“It’s very much a wheat,” Gillman says in regard to how Kernza behaves and ages. “From what I’ve learned over my years in distillation, wheat seems to take the longest time to come around in the barrel and mature … so you have to be patient on the back end.”

Patience is something these distillers appear willing to invest, along with the added cost and legwork. While some are still waiting for their first Kernza whiskeys to mature, all have ideas firing about how they’ll tackle their next batches, motivated by the sustainability benefits as well as the flavors. As Lancette says, “We’re all aboard the Kernza train.”

“We’re about to tackle batch number two,” Anderson-Tarver says. “This batch [of Kernza] came not milled, so we’re excited to see what characteristics come from the dehulled grain and take it from there.” While the first batch is still aging, Anderson-Tarver says the team is already so impressed with how the young spirit tastes that they might play around with some in cocktails in their taproom.

As more distillers work with Kernza, and more growers plant it, it will become more affordable and feasible to source—a perfect circle for an intriguing and impactful perennial grain.

Courtney Iseman is a freelancer writer focused on the craft-beverage space, based in Brooklyn, New York.

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