Hard seltzer is here to stay. More and more, consumers are reaching for the refreshing, clean, and crisp alcoholic water as a low-cal alternative to beer or wine.
We’re die-hard beer geeks… but even the most hardcore fans can appreciate the extra thirst-quenching ability of a nice, cold hard seltzer. But instead of White Claw or Truly, we prefer making our own!
Hard seltzer can be made at home in a few easy steps:
- Boil sugar in some distilled or reverse osmosis water
- Pitch yeast with lots of yeast nutrients
- Ferment for 2 weeks at 68°F to 70°F
- Add flavoring and carbonate
Since hard seltzer is a fermented beverage, you’ll need a bit of special equipment. For avid homebrewers, you should have everything already.
Seltzer is a soft drink made from water and carbon dioxide. It’s basically the same as club soda, soda water, or sparkling water, but seltzer does not usually have added salt or minerals. Simply put, it’s just fizzy water.
Hard Seltzer is boozy seltzer, most of the time around 5% ABV. Popularized in recent years by brands like White Claw and Truly, most big beer companies now offer their own version. Usually, hard seltzer is flavored with tropical fruit and other extract based flavoring you might find in flavored sodas.
It didn’t take long for the hard seltzer craze to catch on throughout the craft beer world either. The likes of Evil Twin, Omnipollo, Cigar City, American Solera, and Two Roads all jumped on the hard seltzer train.
What makes hard seltzer so appealing to the masses is the thirst-quenching drinkability and range of flavors. Brewers get creative in crafting unique flavor combinations – usually fruit based – that speak to a huge audience.
Commercial hard seltzers are made one of two ways:
- Mixing water, carbon dioxide (CO2), neutral alcohol (like vodka), and flavoring
- Fermenting a sugary solution, carbonating, and flavoring
Flavors can come from extracts or pure fruits. Most commercial hard seltzer makers prefer extracts for consistency – they also don’t add any carbs or calories.
For homebrewers, the second method is the way to go. Using corn sugar for 100% of the fermentables, it’s straightforward and inexpensive to make hard seltzer at home.
Hard seltzer needs to check a few key boxes:
- Minimal alcoholic bite
- No fermentation off-flavors
- Very low residual sweetness
- Brilliant clarity
- Highly effervescent
- Interesting and vibrant flavoring
- Massively refreshing
Sounds great, right? Let’s go through what you need to make them.
Corn sugar, also known as dextrose, is all you need in terms of fermentables. You can also use cane sugar. It’s really up to you. I’ve found that dextrose is a bit easier for the yeast to chew through, but your results may vary.
Most hard seltzer is 5% ABV. For that, you’ll need to use 4.7 pounds of dextrose per 5 gallons of water. The starting gravity (OG) should be about 1.038 to 1.040, and it will finish with a final gravity (FG) of about 1.000 to 1.002.
Since hard seltzer is basically just water and sugar, you absolutely need to use great tasting and clean (i.e., neutral) water. Use either reverse osmosis (RO) or distilled water.
You don’t want to use tap water or even most bottled water. High mineral content and hardness will leave your seltzer tasting sharp and solvent-like. It could also contribute to a yellow, hazy appearance.
As for water volume, you’ll lose about a quarter gallon of fermented seltzer to the yeast trub. That means, if you’re making a 5 gallon batch, use about 5.25 gallons of water total.
Neutral, clean fermenting yeast is what you’ll want for hard seltzer.
Consider the use of any of the following ale or wine yeasts:
Since hard seltzer is made with 100% sugar, typical beer and wine yeasts are missing key nutrients for a healthy fermentation. Normal beer wort (or wine must) has a range of yeast-friendly nutrients from the malt (or grapes).
Because of this, the use of additional yeast nutrients and other additives is essential when making hard seltzer.
We use a few additives to help the fermentation in a number of ways:
- Potassium bicarbonate to boost the buffering capability and keep the pH from dropping too low.
- Yeast nutrient that provides the necessary vitamins, minerals, and nitrogen.
- Clarifying agent to make the hard seltzer beautiful and clear.
We recommend using a cocktail of the following additives to give your yeast the best chance to fully attenuate:
- Go Ferm Protect: 10g per 5 gallons
Provides the yeast cell walls with protection against stress caused by the harsh environment.
- BioFine Clear: 1/4 teaspoon per 5 gallons to the fermenter before cold crashing
The best way to get bright and clean flavors, like the top commercial hard seltzer brands, is with flavoring extracts. They’re often shunned in the homebrewing world, but for hard seltzer, the consistency and range of flavors makes them very convenient to use.
Our favorite is OliveNation’s range of flavor extracts but SodaStream extracts available at the grocery store work great as well.
For dosing your fermented hard seltzer with flavor, pull a 250ml sample before packaging. Add a small amount of extract and taste. Repeat until you’ve found the desired flavor profile and scale up to the full batch size. Add the scaled amount to your keg or bottling bucket when racking.
For 5 gallons, it’s usually around 1 to 2 ounces of extract – but every brand and flavor is different.
- 4.9 lb of Corn Sugar (Dextrose)
- 5.25 gallons of distilled or RO water
- Fermaid O Yeast Nutrient: 30g added with the sugar
- Potassium Bicarbonate: 3g added with the sugar
- Go Ferm Protect: 10g when pitching yeast
- BioFine Clear: 1/4 teaspoon to the fermenter before cold crashing
- 1 ounce of Watermelon Extract
- 1 sachet (11.5g) of Safale US-05 American Ale Yeast
The hard seltzer making process is very straightforward. If you need more details into the process, it’s very similar to brewing extract beers.
- Bring 1 gallon of distilled or RO water to a boil in a 2 to 3-gallon pot
- Remove from heat and stir in corn sugar
- Stir well to dissolve the sugar
- Add Fermaid O and Potassium Bicarbonate
- Chill pot in an ice bath to around 100°F
- Pour remaining distilled water into a clean and sanitized fermenter
- Pour the warm water-sugar solution directly into the cold water.
- Allow the temperature to stabilize to 70°F
- Oxygenate solution
- Pitch the yeast and Go Ferm Protect
- Ferment at 68°F to 70°F for 2 weeks.
- Add ¼ teaspoon of BioFine Clear and cold crash to around 32°F for 2 days.
- Add flavoring extract to a clean keg or bottling bucket.
- Rack the hard seltzer to keg or bottling bucket
- Keg or bottle with carbonation of 2.5 to 3.0 volumes CO2
Cold, clean, and damn refreshing, hard seltzer has won over the hearts of many die-hard beer drinkers. There’s no denying that it can be delicious and thirst-quenching. Not only that, everyone seems to love it – from wine drinkers, to cocktail enthusiasts, to craft beer lovers.
Making your own hard seltzer is inexpensive and quick. And the only special equipment you really need is a fermenter and a keg or bottling equipment. Experimenting with extracts and flavorings can be fun and you’ll find a new flavor combination that you absolutely love.
Give hard seltzer a go. You’ll be surprised at how quickly the keg disappears.