Spare Tonic Is Taking the Waste Out of Whey

Spare Tonic is a new drink made with whey, a by-product of yogurt-making. Photo: Joe Linegman

Spending workday afternoons at Westchester brewpubs is a new experience for Adam Kaye, a professionally trained chef who built his career over two decades in the kitchens of Blue Hill and its Stone Barns sibling, most recently as culinary director. But there he was at the River Outpost in Peekskill one Tuesday in mid-April, tinkering with a new flavor of Spare Tonic, the whey-based carbonated beverage he and his brother Jeremy have just launched on the market. It’s the first product to debut from their Spare Food Co., a venture Adam describes as “a value-added upcycled food platform, specifically looking at unused food from farms, from processors, and beyond.”

Spare Tonic, available in three fruit-and-spice-infused flavors, is less simple thirst-quencher and more sleekly branded response to the problem of food waste, a topic Kaye’s been obsessed with for years. In 2015, he and Blue Hill chef-partner Dan Barber organized the restaurant’s wastED pop-up, a three-week celebration of fish spines, fruit cores, and other salvaged scraps. He returned from the London edition in 2017 with a career-changing conviction: “There’s a there there,” he says he thought. “This idea of latent value in our food system — how can we capture that at scale? How can we use culinary innovation to take that latent value and create delicious food?”

The Kaye brothers founded Spare Food in 2018 in order to answer that question. “I just kept coming back to whey,” says Adam, referring to the watery remains of traditional strained-yogurt-making, a booming industry in New York State and the source of an acidic waste product that fosters algae growth in waterways, depleting them of oxygen and ravaging aquatic ecosystems. “In 2018, 1 billion pounds of whey was produced in New York State alone,” says Kaye, who, like other environmentally minded chefs, had been trying to find kitchen applications for the stuff for years — poaching vegetables, brining meats, reducing it into caramel. But now, with new purpose, he and Jeremy set out to build a brand around it, a journey that took them from the WeWork Food Labs accelerator to the Cornell Food Venture Center in Geneva, where food scientists and fermented-beverage experts helped them develop a process that Kaye describes as “more akin to brewing beer” than anything else. The perfect co-manufacturer was close at hand: “I reached out to an old friend of mine at Captain Lawrence, Scott Vaccaro, whose original brewery was five minutes from Stone Barns,” says Kaye. “He said, ‘I have a satellite brewhouse in Peekskill, which I had to close because of COVID. Hire my furloughed brewer. He’s incredible.’ The first time in the brewery, it worked perfectly.”

This isn’t the only relationship Kaye has leveraged. Every Monday morning, he drives a truck to Red Hook, where he picks up several hundred gallons of whey from his friend Homa Dashtaki, owner of the White Moustache yogurt company and, as a marketer of cooking and drinking whey since 2014, something of a whey-repurposing evangelist in her own right. He delivers it to the brewery, where it’s fermented; blended with fruit juices, concentrates, and essences; sweetened with a touch of honey; and carbonated — a process that Kaye says rids it of whey’s natural sour-milk flavor profile. The slim aluminum cans bear the buzzwords you’d expect from a brand incubated in a 21st-century food-lab accelerator: probiotic, upcycled, non-GMO, immunity. But the ingredient list is reassuringly short and the drink itself, in peach-turmeric, blueberry-ginger, and cucumber-lime flavors, is just vaguely sweet, with a pleasing lactic tang and thirst-quenching effervescence. “I look at it like kombucha 2.0,” Kaye says, “only with better nutritionals in terms of the electrolytes and the B vitamins that you’re getting from whey.” Not to mention a compelling sustainability backstory. (For retail outlets, see

Spare Tonic Is Taking the Waste Out of Whey