This week I take a look at the best practices for making hard seltzer at home. Seltzer has grown in popularity the last decade, as many Craft breweries have expanded their product line to appeal to a wider variety of drinkers, but home brewers can easily make seltzer at home.
Hard Seltzer Basics
Hard seltzer is remarkably easy to make at home, and the average homebrewer has all the equipment needed – typically consisting of a large pot for the boil, fermenter and accessories for sanitizing, transferring and packaging the final product. Hard seltzer is made from simple cane or beet sugar which is boiled up with water, and then cooled and fermented to create the base seltzer. Then various artificial or natural flavors can be added to get the flavor of seltzer you desire.
A Simple Hard Seltzer Recipe
- 5.5 gallons (21 L) of water
- 3.75 lbs (1.7 kg) of Cane (Grocery store) Sugar
- 1 pouch of White Labs California Ale Yeast WLP001
- Phosphoric or Lactic Acid for pH adjustment
- Yeast Nutrient (DAP or other – optional – see below)
- Artificial fruit flavor of your choice
This will create a 5 gal (19 liter) batch of seltzer with an OG of 1.035, FG of 0.992 and about 5.5% alcohol. You can lower the sugar level if you prefer a lower alcohol option.
Brewing Your Seltzer
Heat the water in a large pot and mix in the sugar until it fully dissolves. The sugar is typically boiled with the full volume of water to sanitize, but if you don’t have a large pot you can boil the sugar with part of the water and then add cold water to bring your starting volume up to 5 gallons (19 l) for fermentation. You don’t need to do a long boil, as there are no volatiles to boil off, so a 10-15 minute boil is fine.
Fermentation pH and Seltzer
After boiling you need to chill the water/sugar mix down to room temperature before pitching your yeast. If you have access to a pH meter, I recommend measuring the pH of the mixture before fermenting. Because you are not using any malts (which are acidic) it is not unusual for the pH to be high. You can add phosphoric or lactic acid to bring the pH down to at least 5.0 before fermenting. You can do this by slowly adding some lactic or phosphoric acid to the mix. However since there is no buffering capacity (no malt) in the mix, the pH will drop rather rapidly as you add the acid, so I would probably add something like 1/4 to 1/2 tsp (1-2 ml) at a time, mix it in and then measure again. If you don’t have access to a pH meter, then perhaps use 1 tsp of lactic acid and let it go as the pH will drop further once fermentation starts.
Yeast Nutrients
Yeast nutrients can aid in fermenting a seltzer cleanly. Nitrogen, in particular, is lacking in regular cane sugar, so a nitrogen boosting nutrient like DAP, Fermaid-O or Fermaid-K can help. A variety of yeast providers now sell yeast nutrients in small packets to use with home brewed seltzers. You can also use typical nitrogen additives like DAP, Fermaid-O or Fermaid-K, though calculating the exact amount to add and YAN nitrogen levels is a bit beyond the level of this article. If you want to get in the ballpark on nutrients you can consider using the mead nutrient tool in BeerSmith which will give you a conservative estimate based on original gravity and yeast used. Yeast nutrients are often added in four equal staggered additions at 24 hours, 48 hours, 72 hours and at the 1/3 sugar break (or 7 days).
Fermentation
Because you are fermenting pure sugar, the fermentation is a fairly straightforward affair. The main fermentation typically only takes a few days and there is little need for aging a seltzer. Your main concern is waiting for the yeast to drop out and clarity to improve, which is why it is good to use a high attenuation yeast that flocculates out quickly. You can aid the flocculation by rapidly chilling the seltzer to near freezing or filtering if needed. The finishing gravity for seltzers is usually well below 1.000.
Flavoring Options
Unflavored seltzer is a bit boring though it can be used in mixed drinks. The simplest way to flavor your seltzer is to use artificial flavoring additives. The advantage of these is that they usually require only small additions and they can be added “to taste” until you get your desired flavor balance. I have an article on how to do this with beer here, basically by premeasuring your beverage and additions until it tastes good and then scaling up. The same method applies with seltzers.
A second option is to use fruits or natural flavorings. The challenge with these is that many are fermentable, so if you add something like fruit puree or fruit juice to your keg of seltzer you run the risk of kicking off another fermentation. This can be a real disaster if you then try bottling it. So if you are considering using any fermentable flavoring like fruit, you should first add a dose of potassium metabisulfites and potassium sorbate to your seltzer to inhibit future fermentation.
This process of halting fermentation and then adding fruit is called backsweetening and is covered in more detail in this article. I personally recommend storing any back sweetened seltzer in a keg and not bottling it as there is always a risk of a secondary fermentation which can create bottle bombs. Kegs, in contrast, can typically handle the extra pressure if you accidentally get another fermentation going.
Packaging Seltzer
Seltzer is almost always carbonated. If you are using most artificial flavors or unflavored seltzer it is possible to bottle it with a bit of corn sugar to naturally carbonate just like you would with beer. However if you backsweeten your seltzer using a fermentable fruit, juice or sweetener, you can’t really carbonate it in the bottle as you already inhibited fermentation. Also bottling with backsweetening runs a high risk of starting fermentation again resulting in a bottle bomb. As a result, your best bet is to keg your seltzer and then pressure carbonate it again just like you would with kegged beer.
I hope you enjoyed this week’s article on brewing seltzers. Thanks for joining me on the BeerSmith Home Brewing Blog. If you want to take the guesswork out of brewing, please try my BeerSmith recipe software from BeerSmith.com. Be sure to sign up for my newsletter or my podcast (also on itune and youtube) for more great tips on homebrewing.