How to Ferment Hard Seltzer or Cider at Home

You’ve mastered making cocktails at home and probably even crafted your own cocktail ingredients. But have you tried home brewing or fermentation? Working with yeast and siphons may sound and look intimidating. But Emma Christensen covers the fermentation process in her book, Hard Seltzer, Iced Tea, Kombucha, and Cider. All you need are a couple of weeks, equipment, and gumption. Here, she breaks down how to ferment and even offers some of her expert tips.

As a newbie, you might make a mess, but that’s just part of the learning process, writes Christensen. However, just to be safe, start by bottling water just to get a feel for how the equipment, like the siphon and bottle capper, work. And for those nervous about the sanitizing and bottling steps, Christensen suggests reading those sections of her book carefully and watching instructive videos online.

Days 1 to 6

Sanitize your equipment

Before you touch a single ingredient, clean your equipment. Scrub everything with soapy water and follow that by sanitizing it. Do this in your fermenter, which needs to be sanitized anyway, or any other large container where you can submerge the equipment, such as the air locks and spoons, in the sanitizer for a minute or two. Make sure to also sanitize the mouth of your fermenter. Sanitized equipment can be used wet or dry. “After you’re done sanitizing all your equipment, save a small container or a spray bottle of sanitizer in case you have any last-minute sanitizing needs,” Christensen suggests.

Mix your sugary base

Once your fermenter is pristine, pour the sugar in and cover it with the liquid base of your recipe. Sprinkle yeast across the liquid’s surface. (Christensen prefers champagne yeast because it’s easy to work with and doesn’t impart much residual flavor.) After a couple of minutes when the grains have dissolved, mix it with a sanitized whisk for about 30 to 60 seconds until there is a bit of foam. “Whisking your sugary base incorporates oxygen into the mixture, which is beneficial to the yeast and helps ensure a strong fermentation,” Christensen explains. Now seal the fermenter with the lid and rubber stopper. Fill the air lock with either your reserved sanitizer or vodka.

Store your fermentation mixture

Place your fermenting brew somewhere dark and a little warm with not much traffic, like a kitchen cupboard or laundry room. You’ll want it out of the way but still be able to keep an eye on things. “If you need to store your beverage on the counter while it ferments, wrap it in a thick layer of towels to protect it from the light,” she recommends. And just to be safe, set the fermenter on a towel in the event that happy yeast pushes liquid out of the air lock.

Add yeast nutrients

Even though the fermentation process is hands off for the most part, you need to feed the yeast nutrients. “Yeast nutrients help keep your yeast happy and your fermentation vigorous!” she says. Otherwise, stressed yeast can make for off-flavors or stop the fermentation. Christensen feeds her yeast 1 teaspoon of diammonium phosphate and food-grade urea (mixed with a few tablespoons of warm water) per gallon over three days. Pour the yeast nutrient into the fermenter, gently mixing it in. Repeat over the next two days.

Days 7 to 14

Add and adjust flavors

After a week or so when the fermentation has slowed down, it’s time to add some flavors, such as liqueurs, fruit, or herbs. The ingredients can then be carefully added to the liquid in the fermenter in a sanitized mesh bag. Gently swish it around and return the fermenter to its storage space. After a few days, taste test your brew with a small sanitized measuring cup. “Add more [flavoring] if you’d like a stronger flavor and bottle when you’re happy with how it tastes,” she says. This process can take a minimum of three days. However, Christensen writes that a “week of infusion is typically a good middle ground for extracting the best flavor and staying on schedule.”

Bottle

When the mixture has stopped fermenting (i.e. it’s no longer bubbling in the air lock), it’s time to bottle it up. You definitely don’t want to bottle it while it’s still fermenting else you risk cracking the bottle and a big mess to clean up. If you’re not sure, simply wait a few more days to bottle. Once you’re ready, place a sanitized stockpot on a table or chair about a foot or two below the fermenter. Add corn sugar dissolved in a half cup of water to the sanitized stockpot. This will carbonate the drink.

After removing the fermenter’s lid, gently insert the autosiphon along one side of the fermenter until it hits the bottom. Place the other end of the tube in the stockpot. Hold it in place with one hand to prevent it from jumping around, and, with the other, pump the autosiphon a few times to get the liquid flowing. Siphon all the liquid from the fermenter. When nearing the bottom, tilt the vessel to capture as much liquid as possible, leaving behind the solid ingredients and the sludge.

Next, place the filled stockpot on the counter with the autosiphon and put the bottles where the stockpot was below. Christensen puts the bottles on a tray to contain any possible spillage. Once you attach the bottle filler to the siphon tube, insert it in the bottle, pressing the tip to the bottom. Then pump the autosiphon to start the flow. When the bottle is filled up to its lip, put out the bottle filler. “Once the filler is removed from the bottle, it will leave the exact right amount of empty headspace in the bottle so the liquid can carbonate,” she writes. Repeat this process until there is no liquid left in the stockpot.

To cap the bottles, first place a clean dish towel on the counter to prevent the bottles from sliding when you cap them. Put a sanitized bottle cap over the bottle’s mouth and the middle of the bottle capper’s circular part over the bottle cap. Press down until the capper’s handles are parallel to the counter.

Store your bottles

Keep your bottled brew in a box so not only are they easy to transport but they’ll contain any unexpected messes from overcarbonation. Store the bottles in a dark place at room temperature, waiting a week before you crack one open. “These homemade drinks are meant to be consumed fresh, but they can be stored for up to 3 months without any significant change in quality or flavor,” Christensen writes.

Enjoy your homemade drink

Now the moment of truth: time to taste your creation. “If your drink isn’t as sweet as you’d like, add a few tablespoons of simple syrup to your glass,” suggests Christensen.