DOBBS FERRY, NY. — A chef-led startup has developed a line of sparkling beverages based on acid whey, the nutrient-rich liquid leftover from yogurt production.

Brothers Adam and Jeremy Kaye founded the Spare Food Co. to transform unused and overlooked ingredients into nutritious products. This past April, the company debuted its first offering, Spare Tonic, formulated with whey sourced from The White Moustache, a Brooklyn, NY-based yogurt maker, plus fruit, spices and local honey. Flavors include peach and turmeric, blueberry and ginger, cucumber and lime, and lemon and ginger.

The beverages provide a good source of protein, potassium and magnesium and an excellent source of calcium and vitamins B12 and B6. They also contain probiotics from the whey, said Adam Kaye, chief culinary officer.

“The ethos of The Spare Food Co. is captured in every can of Spare Tonic,” said Adam Kaye. “We take an unused ingredient and craft it into a delicious food. In the process, we eliminate climate-destructive waste, support a regional food system of farmers, producers and vendors, and bring a healthful product to market.”

For every cup of strained yogurt produced, two cups or three cups of whey are created. Production of Greek-style yogurt in New York state generates an estimated billion lbs per year of whey, Adam Kaye said. Applications include fertilizer, feed and energy generation; however, “most of it is getting pre-treated and disposed,” he said.

“So often what is being discarded in our food system is where so much of the nutrition is,” he said. “In the case of strained yogurt, the fact that you’re losing up to three quarters of your raw material, which is where the good stuff is, is mind-blowing. What’s even more mind-blowing is there is a multibillion industry that is predicated upon losing three-quarters of the volume of your raw material. I don’t think you’d pass business school if you had to propose that as a business.”

Spare Tonic is sold in area specialty retailers and restaurants and available to select regions through online grocers Imperfect Foods and FreshDirect. The company plans to expand production and distribution this year. Other focuses in the future may include surplus produce, overlooked parts of plants and additional byproducts of food manufacturing processes, he said.

“We’re not done with whey yet,” Adam Kaye said. “There’s many line extensions of whey-based beverages that are certainly in the pipeline and in the cards... Whey as an ingredient generally beyond beverages has great potential.”

Prior to founding the business, Adam Kaye was chef and culinary director at Blue Hill at Stone Barns, a high-end farm-to-table restaurant in the Hudson Valley. Jeremy Kaye, chief executive officer of Spare Food Co., previously held a product development role at Patagonia, where he helped create and launch a sustainable sportswear business. The brothers are fourth-generation food entrepreneurs, Adam Kaye said.

Spare Food Co. was among 10 startups selected to receive seed grant funding from The Kroger Co. Zero Hunger/Zero Waste Foundation Innovation Fund last May. Adam Kaye recently joined the board of the Upcycled Food Association, a non-profit organization focused on reducing food waste.

“This whole upcycled food world is relatively nascent, and we are at the cutting edge of that,” he said. “What we’re doing here is, in our view, we’re fixing a broken food system. We are rewiring a highly inefficient system.”