Homemade Hard Seltzer: How to Make Flavored Hard Seltzer at Home

If you didn’t read our last post How to Make Hard Seltzer at Home, go check it out. We walk through a couple different ways to make hard seltzer at home as well as a couple different ways to flavor the seltzer.

This time, we’ll walk you through our first foray into making hard seltzer. Having brewed many batches of beer over the past 10+ years, making a hard seltzer seems like its going to be a walk in the park (famous last words, right?). In general, it seems like a very simple process, not requiring all of the precision timing of mash rest, hop additions and other measurements that brewing a good beer might require. So, here goes nothing!

We started with this simple ingredient list:

• Corn Sugar (Dextrose)
• Yeast / Safale US-05
• Purified Water
• Natural Grapefruit Flavoring

We chose to do a 3-gallon batch as a trial and we were shooting a bit high on the ABV, looking for 5-6% figuring that we could cover up any imperfections with natural flavoring. A 3-gallon batch would be the perfect amount for our Ss Brewtech Brew Bucket Mini Fermenter.

We started by adding 1.5 gallons of purified water to a kettle and bringing that to a boil. Since we were doing such a small batch, we just did this on the stovetop. We set aside another 1.5 gallons of water to add to the fermenter to allow us to help bring the temperature of the boiling water down quicker once that step was complete.

Once the water came to a boil, we slowly stirred in 3 pounds of corn sugar (dextrose) until it dissolved completely and then we let it boil for about 10 minutes. The 3 pounds of corn sugar dissolved into the water very easily. Once the boil process was complete, we pulled it off of the heat and poured it into our fermenter allowing it to mix with the other 1.5 gallons, giving us about 3 gallons. Next, we waited for the sugar water to cool down so that we could pitch the yeast.

Side note, we completely underestimated how long it’d take the sugar water to cool down to below 80F, so we didn’t have a chiller ready. We used the set it and forget it method. Typically, we brew 15-20 gallon batches of beer and we use a chiller to help cool the wort down. We made the huge mistake of assuming that 3-gallons would cool down relatively quickly… it did not.

Once the liquid had cooled down to about 72F, we added the Safale US-05 yeast (more on that later), covered the fermenter and let it start to do its thing.

Gallery: Making Hard Seltzer at Home

Fermenting Hard Seltzer

Corn sugar is 100% fermentable, so the expectation was to see fermentation start quickly and finish quickly. Especially considering the fact that we used a full packet of Safale US-05 for a 3 gallon batch, however, that was not the case at all. Fermentation wasn’t visible until the 3rd day, and even then, it was not at all vigorous. We had a short trip planned, so rather than leaving it for the 7-10 days that were originally planned, we ended up leaving it for just over 2 weeks – 15 days in total.

After 15 days in the fermenter, I decided that whether it was fermented or not, we were going to add some flavor and keg it up — we had less than $15 invested in this between the corn sugar and yeast, so what the heck, right? Upon opening the fermenter and looking at the “hard seltzer”, it appeared much like most hard seltzers that we’ve seen at our local breweries – a bit white and cloudy. But it was a gravity reading that would let us determine if what we had was actually hard seltzer or just a bucket of partially fermented sugar water.

I failed to take an original gravity reading (rookie mistake), but decided to take a final gravity reading as that would help determine whether or not the hard seltzer had actually fermented or not. The gravity reading revealed that fermentation was certainly not complete. With a final gravity of 1.030, we had basically brewed a batch of yeasty sugar water.

Thoughts on why the seltzer water didn’t completely ferment:

• Bad packet of yeast – not likely as dry yeast has always done its job for me in the past
• Failure to rehydrate the yeast – also not likely; some brewers maintain the rehydration is a necessary step, however Safale, the yeast manufacturer, says that it is not required
• Wort / sugar water too hot when pitching the yeast – this is a distinct possibility as I decided to trust the stick on thermometer on when determining the temperature of the liquid – also, the temperature of the liquid in the center of the vessel could have been much hotter than that around the perimeter – this could have killed off most of the yeast
• No minerals or nutrients to help the yeast out – since this was literally just a bucket full of sugar water, next time I’ll add yeast nutrient when pitching the yeast in order to give the yeast a little something extra to feed on
• Wrong type of yeast – after completing this, I began doing a bit more reading and it turns out that most brewers are using a champagne yeast when brewing seltzers – I’ll try that next time
• Hydrometer reading incorrectly – ruled this out after a zero reading in

Hard Seltzer Color & Appearance

Take a look at the images below that compares the color of hard seltzers from a couple of our local breweries as with our homemade hard seltzer.

You’ll notice that each of the hard seltzers has a white, cloudy look to it. This is going to be common in most homebrewed seltzers. This cloudy haze can be removed through filtration. Since most homebrewers don’t have a filtration system, I figured we’d try a different method of filtration – fining hard seltzer using gelatin (using our method of clarifying beer through adding gelatin).

Kegging, Flavoring and Fining Homemade Hard Seltzer

Regardless of the fact that this had only minimally or partially fermented, I had already made my mind up that this would be flavored, kegged and carbonated as a test batch. We drained our Brew Bucket fermenter directly into our cleaned & sanitized keg, then added gelatin in hopes of clarifying the seltzer, and added our natural grapefruit flavoring.

Once in the keg, it was hooked up to CO2 and purged. It was then set to 40psi and left to rest for a few days to allow the seltzer to carbonate. Once carbonated, we poured off about 12oz to get rid of the gelatin and anything that settled to the bottom. Just a quick note regarding fining seltzer with gelatin – it did not work. When fining beer with gelatin, there is a noticeable difference, however with hard seltzer, the difference was negligible.

Next time we try this, we will definitely be making a few changes:

• Using champagne yeast
• Adding yeast nutrient
• Being better about taking measurements – both original and final gravity as well as measuring temperatures prior to adding yeast as well as during fermentation

Have you tried brewing your own hard seltzer? Let us know in the comments below!