Tips for DIY Fermentation

fermentation-strawberry-water-kefir-crdt-lara-ferroniWith DIY projects more popular than ever, imbibers are increasingly making their own of kombuchas, kefirs and sodas at home (check out our DIY Pinterest board for ideas). Back in our May/June 2015 issue, Kate Simon tackles the topic of at-home fizz fests, complete with recipes for everything from kombucha to kvass to water kefir and lacto-fermented sodas. Now, in honor of the current Home Issue, we’ve revived these helpful tips to help you maximize your ferments and avoid messy disasters at home.

Keep it clean. We can’t emphasize this enough. Cleanliness is critical with fermented drinks. Sterilized bottles and tools are essential for keeping good yeasts in and bad bacteria out. These unwelcome outsiders can infect your brew with funky flavors and even cause the entire fermentation to halt. To help prevent the cross-contamination, run your gear through the sanitize cycle in your dishwasher, cover with water and boil on the stovetop for several minutes, or pick up a commercial sanitizer like Star San at your local homebrew store (or on Amazon) to use before you get started.

Reach for plastic. Fermentation builds carbonation, and carbonation means those bottles are tight under pressure. Added pressure means things can fizz over when opened, or even worse, the bottle could burst. To help avoid any added messes, use plastic bottles (sanitized soda bottles work like a charm), which can help you keep tabs on the progression of your fermentation. “Until you have a feel for how quickly your beverage carbonates, it’s helpful to keep it in plastic bottles,” says Emma Christensen, author of True Brews and Brew Better Beer, “when the bottle feels rock solid, it’s ready.”

Chill out. As noted above, while the fermentation continues, pressure builds within the bottles. Once your drink has reached the desired level of carbonation, it’s important to move it to the refrigerator to stop fermentation from continuing and pressure building. Most yeasts go dormant at a low temperature, so refrigeration is key to keeping unwanted pressure from building.

When in doubt, throw it out. Fermentation is as much an art as it is a science, and on occasion, unexpected things can happen. If you see mold growing on top of your ferment, throw it out and start over. Usually, mold forms when the ambient room temperature is too low for strong fermentation, so find a warmer location (or consider using a heat pad) and try again.

Be flexible, and have fun. “There are a lot of variations in how fermented soda can shape up, based on temperature, the culture you’re using—and this is part of the fun,” says Ariana Mullins, author of And Here We Are at the Table and the blog And Here We Are. “You may need to add more sugar or an acidic element, or it may ferment faster or slower than you expect. Look at it as a fun and interesting project, and learn as you go.”