While distillers can produce a seemingly infinite variety of flavors via ingredients, fermentation, distillation, and aging, it’s often fruitful—in the pursuit of characterful spirits—to focus more narrowly on one spoke of the sensory wheel. One such path to impactful flavor is through an often-overlooked ingredient: peppers—and their capsaicin, the compound in chiles that we perceive as hot and spicy.
Distilling with peppers can be challenging. The variety of peppers commercially available is staggering, then there’s the decision of whether to include capsaicin—or, how much to include—in the bottled spirit.
Spicy spirits appear to be gaining traction, but they’re polarizing. Chiles themselves may have Scoville units, but for spirits, there is no agreed-upon metric to convey the exact level of spice consumers should expect. People’s sensitivities also vary widely, so ultimately, it’s hard to know what you’re going to get.
Exploring Peppers’ Not-So-Spicy Flavors
There is an important distinction between the flavor of peppers—including chiles—and the body’s reaction to capsaicin, which is the lipophilic compound that causes a burning sensation when it meets our mucous membranes.
Most people think of peppers as predominantly spicy things, but there are plenty of cultivated varieties with fruits that aren’t spicy. Although bell peppers are members of the genus Capsicum, they don’t produce any capsaicin. (They are the only peppers of that genus that don’t.) Yet they’re versatile and prized by cooks, exhibiting different flavors at each phase of maturation—green, yellow, and red.
Under sensory evaluation, green bell peppers score primarily on grassy, green, cucumber, and bitterness attributes. One of their most significant flavor compounds should be familiar to many distillers, especially those who make of rye whiskey or agave spirits: 2-methoxy-3-isobutylpyrazine, more commonly known as the “bell-pepper pyrazine.” Known precisely for smelling like green peppers, this compound has a very low odor threshold—we can detect it at a point below the level of parts per trillion. Other compounds that make contributions, even if relatively minor, include those that smell “green,” such as aldehydes that evoke cucumber or grass.
As bell peppers ripen, the concentration of most of these volatile compounds decreases. The notable exceptions are (E)-2-hexenal and (E)-2-hexanol, associated with sweet and fruity aromas, which increase as peppers ripen. That change helps explain the aroma and flavor differences among peppers of varying colors. Bell peppers always start off green because of the chlorophyll pigments that are vital for photosynthesis. As the peppers ripen, the chlorophyll pigments start to decompose, and other pigments replace them—violaxanthin is largely responsible for the color in yellow peppers; other contributors include lutein and beta-carotene, the pigments that provide the yellow of egg yolks and the orange of carrots, respectively. In red bell peppers, meanwhile, the color is a product of the carotenoids capsanthin and capsorubin (also known as “paprika ketones”).
Sunlight increases the accumulation of carotenoids, just as it accelerates the degradation of chlorophyll. Researchers have observed decreased carotenoid biosynthesis in fruit grown under shaded conditions; this takes place when the expression of enzymes found within certain fruits is repressed because of inadequate light exposure.
Distillers who use peppers in the production of a spirit should pay attention to where they’re sourcing their fruit. While flavonoids possess antioxidants, it’s the carotenoids, lipids, and amino acids that are the major precursors of flavor volatiles. In peppers, including bell peppers, environmental variation impacts these volatile compounds more strongly than genetic influences.
So, while knowing something about the genetic background of a pepper variety is useful, it’s better to be aware of how a supplier has grown their crop because that will impact the flavor.
Bringing the Heat
The heat in chiles comes from capsaicinoids, which include several different compounds found in a variety of peppers. The most dominant is capsaicin.
When ingested, capsaicinoids work by binding to receptors in the mucous membrane—usually in the mouth, unless you mistakenly rub your eyes after eating something spicy with your fingers. The receptor type is the same one associated with our perception of heat and physical abrasion, which is why hot chiles tend to produce those sensations.
While those sensations are very real, it’s notable that the peppers themselves don’t do any physical damage or harm to the tissue inside your body. The painful sensations, meanwhile, also lead to the production of endorphins, the body’s own compounds that act as natural painkillers. While this reaction helps to explain why many people enjoy hot chiles and spicy food, capsaicin itself is still a toxic compound. However, no chile contains a concentration high enough to be toxic or to be more than a severe irritant to humans.
If you’re distilling with hot chiles, ensuring that some capsaicin remains in the final bottled spirit isn’t so simple as throwing some peppers into the pot as the still heats up for a run. You see, capsaicin is hydrophobic—it’s not soluble in water. But it is soluble in alcohol. By itself, it’s colorless, odorless, and has a boiling point around 410°F (210°C)—so, chemically, it won’t come over in a typical distillation. You have to extract it another way. Most “spicy” spirits involve an addition of capsaicin after distillation.
Many distillers working with chile peppers opt to steep dried ones; the capsaicin usually comes out first, while longer steeping allows the extraction of more of the vegetal, herbal complexity of the peppers into the spirit.
Making Chile Gin at Letherbee
Chicago’s Letherbee Distillers provides one example of how a pepper spirit can work.
In 2019, the distillery released a version of their seasonal Vernal Gin flavored with green chiles. Fresh poblanos and green bell peppers added to the gin’s vegetal and grassy character; the botanicals also included juniper, coriander, and lemon peel, while the spicy finish came from jalapeños and Hatch green chiles.
Letherbee owner Brent Engel says they were aware from the start that it would be a multistep process. “We always knew it was going to be post-distillation steeping; that was the core idea for us,” he says.
However, they also decided to distill some alcohol that had been macerated first with chiles. That would not be where the bulk of the pepper character came from, but they wanted to see what other, more nuanced flavors they could pull from the fruit.
“It’s one of those things that in my opinion creates a premium product from an average product,” Engel says. “The distillation and getting those aromatics made it a more elevated or luxurious product.”
There were, of course, the vegetal notes that one would expect from a spirit macerated with chiles. However, the distillers also found perceptible floral notes in the resulting distillate, and those added complexity to the final gin. Macerating the jalapeños and Hatch green chiles, meanwhile, lent the gin a juicier mouthfeel.
Engel says the seasonal gin was a success, possibly delivering its flavors at the right time for the market. “A lot of the time . . . the success of [our seasonals] depends on what’s trending at the moment,” he says. “In those years, we were closer to the beginning years of mezcal really exploding, so people were using a lot of Ancho Reyes. And so, we were able to kind of capitalize on that trend.”
Choosing a Spirit for Chiles
Cocktails that feature agave spirits and the ingredients commonly paired with them were a natural fit for Letherbee’s spicy Vernal Gin. When used in a familiar cocktail, the New Mexico Hatch chiles and poblano peppers had appeal for many drinkers.
Gin is a relatively unusual vehicle for chile peppers; it’s more common to see vodkas or liqueurs infused with them.
Vodka is a pragmatic choice: With vodka’s neutral (or mostly neutral) base, a producer can focus on executing the most singular pepper flavor possible. Pepper-infused vodka is useful in certain classic cocktails, such as a spicy bloody Mary, Moscow mule, or an adventurous cosmopolitan. Any producers who want to ride the mezcal train while it’s still chugging might consider liqueurs instead, emulating the success of Ancho Reyes—the chile liqueur made in Mexico from Puebla’s famed ancho chiles.
Whether you choose vodka, gin, a liqueur, or something even less traditional, including some peppers in your spirits may be an easy way to spice up your distillery’s portfolio. Plus, with a wide variety of peppers available, and many different ways of handling the fruit, you can get endlessly creative.