fermentation prematurely, before a substantial quantity of alcohol had been produced, by pasteurizing the kombucha, or, they’d cut the kombucha with juice or unfermented tea, diluting the alcohol content down to an acceptable level. But Brew Dr. Kombucha had another idea. What if that excess alcohol wasn’t a problem at all, but an opportunity? Was there a way to recover it without destroying the kombucha? So in 2014, they began laying the groundwork for a new affiliate company, Thomas & Sons Distillery, to pursue the idea. It was clear from the beginning that a traditional pot or column still was not an option: Prolonged exposure to high heat kills the live cultures in kombucha, eliminating one of its core perceived benefits for consumers. Eventually, they hit on the idea of using a vacuum still, a very gentle method of distillation often used for products that are too volatile or too delicate to be exposed to high heat. Under normal conditions, ethanol boils at 173.1 degrees Fahrenheit. By reducing the atmospheric pressure inside the column, vacuum stills allow alcohol to boil at a much lower temperature, minimizing the impact on the feedstock and creating a very soft, delicate spirit. Thomas & Sons’ vacuum still operates under pressure about equivalent to the atmospheric pressure on the moon, which allows them to boil alcohol at just below 100 degrees Fahrenheit and preserve the kombucha’s distinctive cultures. Residence time inside the still is also very short, much less than a minute. “It’s the equivalent of leaving your kombucha in the back of your car on a hot day for 15 seconds,” says Seth O’Malley, head distiller. The process is so successful that 100 percent of Brew Dr. Kombucha is now run through the still. Thomas & Sons’ vacuum still works a bit differently than other stills. Inside, the column is equipped with pairs of conical plates.
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The bottom plate of each pair is fitted with a fin, which agitates the kombucha and creates a very thin layer of solution on the upper cone. Steam is directed up through the plates, causing the film to release its ethanol. By adjusting the quantity of steam, O’Malley can modify the still’s output. “From a technology standpoint, it accomplished everything I needed,” says O’Malley. The first pass produces a spirit around 11 percent alcohol by volume. Because of the way kombucha is produced, it’s naturally high in acetic acid, which can transform into volatile ethyl acetate. “Acetic acid is fun in mezcal or wild ferments,” says Seth, “but we’re not taking that angle.” To neutralize it, he adds baking soda to the low wines before the second distillation, which typically finishes around 50 percent to 60 percent ABV. While Thomas & Son’s distillation equipment is quite precise, it’s not so precise that it captures only pure ethanol—and that’s a very good thing. Brew Dr. Kombucha produces 11 different flavors of kombucha, each featuring a different blend of teas, herbs, and spices. Those flavors come through in the distillate, producing a range of different flavor profiles in the spirit, from spicy and earthy to delicate and floral. With nearly a dozen different “base spirits,” it quickly became clear that Thomas & Sons was a playground for product development. “I was not interested in opening a distillery making products that people here were already making,” says O’Malley. “Especially in Portland, where we have so many distilleries making great products.” Instead, inspired by the range of flavors they had to work with, Thomas & Sons created a portfolio of unique, tea-inspired liqueurs, amari, and spirits, many featuring a strong botanical influence. “It was fun to take tea as a starting point, because it yielded
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