WASHINGTON — Iced coffee is a staple for many coffee drinkers during the hot summer months, but there’s an entirely different way to get a cool caffeine fix — and it comes with bubbles.
No; it’s not soda. It’s a coffee tonic — an unlikely combination that produces a bright, tangy, fizzy beverage perfect for seasonal sipping.
“A coffee tonic, quite simply, is concentrated coffee with tonic water,” says Cory Andreen, the man behind the coffee program at Mockingbird Hill in Northwest D.C. There he serves up coffee tonics, along with seasonal pour-overs, mixed coffee drinks and coffee flights during the sherry bar’s daytime hours.
To make the coffee tonic on Mockingbird Hill’s menu, Andreen mixes about three and a half ounces of tonic with about two ounces of a concentrated coffee. He prefers a Yirgachef coffee from Ethiopia, which he prepares with an aero press.
What makes a coffee tonic so refreshing? The bitterness from the quinic acid, found in both dark-roasted coffees and tonic water, is one reason the unlikely pairing works. Another reason, Andreen says, is the subtle floral hints found in Yirgachef coffees.
“Our approach to [coffee tonics] is very much like that of a gin and tonic; different gin will taste different in different tonics,” says Andreen, who lives in Berlin and travels to D.C. frequently to visit Mockingbird Hill. “When [Yirgachef coffees] are fresh and prepared right, they have a lot of natural sweetness to them. That pairs really well with the tonic water.”
Coffee tonics are not new to the beverage scene. Andreen first heard of the drink about two years ago, when his friends at a roastery in Helsingborg, Sweden, served the combo.
“I still don’t know of very many places that do it,” Andreen says. “A handful of places here in the States and scattered throughout Europe.”
If you’re not close to an establishment that crafts coffee tonics, Andreen says they’re pretty simple to make at home. The biggest challenge is creating a concentrated coffee, so he suggests using a French press, a stovetop espresso maker or an aero press to achieve a strong brew.
Another trick is to chill the coffee before it’s poured over ice and mixed with the tonic water. This will ensure the drink doesn’t dilute too quickly. Andreen says to put the coffee container into an ice bath for a few minutes.
“It takes not even a minute to chill,” he says.
Andreen also suggests using a coffee that’s in season to attain a citrusy, seasonal flavor. During the summer months, the best varieties are from Ethiopia and Kenya; he says they tend to pack “more zest and more acidity.”
Also on the menu at Mockingbird Hill is Andreen’s Kenia Cola — a combination of Kieni coffee, sugar, bitters and soda. The drink was recently featured in The New York Times’ “6 Innovative Iced Coffees.”
“It takes advantage of the fact that Kenyan coffee has a lot of phosphoric acid in it — it’s the only region that has this characteristic, so they always stand out. And phosphoric acid is one of the main ingredients in a Coca-Cola or Pepsi; it’s what gives them their characteristic flavor, so we use that and turn it into a coffee soda that very much tastes like a cola.”
When asked whether the coffee tonic will one day replace the iced coffee, Andreen says no way. In his opinion, “a properly done iced coffee is a treat unto itself,” but he encourages iced coffee fans to give the tonic a try.
Caffeinated Washingtonians don’t need too much of a nudge; Andreen says the coffee tonic is one of the most popular beverages on Mockingbird Hill’s coffee menu.
“I think it’s a really nice alternative to what you’re normally presented with. It doesn’t have to be sugar bomb; it doesn’t have to be something that’s more about the chocolate and the cream than about the coffee. I think it’s nice to celebrate the coffee in a way that highlights that and the way it harmonizes with ingredients you wouldn’t necessarily associate with coffee.”