The ancient Roman army was one of the most formidable battalions in Europe in its heyday, with some attributing that strength from “posca,” a mixed drink of vinegar, sweeteners, and herbs that was a constant in your typical Roman solider’s rations.

They thought the beverage gave them resilience, and a Roman maxim extolled the virtue of posca while also claiming that wine inebriates, “posca fortem, vinum ebrium fecit.” Vinegar’s consumption to improve health and well-being lasts to this day, and when Allison and Stephen Ellsworth found that drinking shots of apple cider vinegar improved their health, they set out to create a more palatable “prebiotic soda.” Originally called “Mother,” the duo—armed with an investment from “Shark Tank” host and CAVU Ventures founder Rohan Oza—decided to rebrand their line of vinegar-containing drinks to Poppi.