Image Credit: (Northern Brewer)

Want to know how to make a crushable hard seltzer that will have everyone asking how you did it? What if I told you it could go from kettle to glass in a week?

Introduction

I’ve never understood the people that scoff at hard seltzer, especially when they’re drinking a Light American Lager and my seltzer has a whole ‘nother percent on them. If you like crushable brews and have a brewing pipeline, that is, a need to keep beverages flowing in your household then you should seriously consider making seltzer. These things will please everyone who tries them, if you follow my advice. At brew club meetups and gatherings my seltzer kegs are routinely nearly empty by the end of the night. With the right process, ingredients and touch you can make a seltzer to sway anyone’s opinion.

I started making hard seltzer when I cut my carb intake back to extreme levels to lose weight. When I make seltzers, they end up around 90 calories per pint, 5% ABV and about 1.5 – 2g carbohydrates per pint. Not bad! It did work. I lost 85 lbs in about a year and a half. But that’s another story. This is about seltzer! Don’t think you can only make 4 or 5% seltzer either. You could easily nail an imperial seltzer by just adding more fermentables (although I recommend putting a disclaimer on that tap or bottle for your guests!). Selter also doesn’t have to feel boring. I have done hard hop water (massive hit), hopped fruit seltzers, fruited seltzers, and wood aged seltzers.

Your imagination should be kicking in about now.

There are a few keys to making good seltzer, and near the end of this post I will give you a cheat sheet if you just want to make good seltzer without understanding why this all works!

1. Acidity
2. Effervescence
3. Low Final Gravity
4. Quality Flavoring Additions
5. Nutrient

Let’s start at the top.

Acidity

Image Credit: (Clean Water Gear, 2020)

What’s the biggest reason we perceive hard seltzer as so refreshing and quaffable? pH. No, really! Commercial seltzers are pH adjusted as low as 3.1 using either citric or malic acid. I’ve also used lactic acid with great success. There are several aspects of acidity to consider, and all are important if you want to impress with your seltzers.

I typically measure my pH at the end of primary fermentation and dose the batch with enough acid to bring the pH down to around 3.2-3.4. I have had excellent results this way. Could you acidify prior to fermentation? Absolutely! I just prefer precision whenever possible, and acidifying before you ferment will mean uncertainty as far as the final pH goes. If the yeast causes it goes too low, you will encounter sourness and rip away any perception of sweetness in the brew.

Enhances Sweetness

Yep, you read that right. The right amount of acidity will cause people to perceive higher amounts of sweetness in food, beer, seltzers or anything consumable really. That’s probably why Americans enjoy acidic foods and drinks; they love sweet things. I specifically ferment with Kveik Lutra for my seltzers since it finishes cleanly in two days but is also known to have a lower finishing pH when compared with other yeasts. Lutra also has a tendency to contribute some citrus notes, which in this case is wonderful!

While there will be VERY little residual sweetness once you ferment this out (I’m talking around .995 or lower FG), acidity is going to convince drinkers that there is indeed an ever-so-slightly sweet character to compliment the dryness of the seltzer.

Increases the Effects of Carbonation

Effervescence, which I’ll talk a bit about in a moment, combined with acidity and a high volume of CO2 creates a distinctly pronounced dry sensation. This is where a lot of the super refreshing qualities of seltzer come from.

Mouthfeel

Acids can contribute to astringency, a dry, puckering sensation in the mouth. Astringency can give a sensation of dryness, which contrasts with the smooth or viscous mouthfeel that sweetness might impart.

Saliva Production

Acidity stimulates saliva production. Saliva is often very slightly alkaline. When it’s produced in response to an acidic beverage like seltzer, it can neutralize some of the acid, leading to a cleaner finish. As a bonus, the increased saliva can wash away residual sugars or other compounds, further contributing to a clean, dry finish.

Effervescence

Image credit: (Savarino, 2020)

Yeah, it’s a big word. Effervescence means the formation and release of gas bubbles in a liquid, typically carbon dioxide, that creates a fizzy or bubbly sensation.

How do you achieve an effervescent hard seltzer? It’s really simple: Carbonate to high volumes of CO2. I aim for about 4 volumes! If you bottle, make sure you are using bottles that can support this much CO2. For those who keg, you have nothing to worry about.

Effervescence has a few things going for it. It creates a wonderful experience that makes use of all senses!

Mouthfeel

High amounts of carbonic acid will cause a prickly sensation in the mouth, which is commonly associated with refreshment.

Aroma Release

When applied to seltzer, this is no different than with beer. CO2 will carry aromatic compounds from the liquid and bring them straight to your nose. Your olfactory system has a lot to do with taste, and your taste buds will thank you for amplifying the good thing that is citrus or other flavors in your seltzer.

Visual Appeal

The sight of bubbles rising to the surface and persisting as a fizzy head can be visually appealing to many. It can indicate freshness and quality, setting expectations for the drinking experience.

Sound

The sound of a seltzer being poured, with the fizzing and bubbling noises, can enhance the overall sensory experience. It can create anticipation and set the stage for a refreshing drink.

Final Gravity

Your FG with a seltzer should be very low. You really do need to aim for dry and attenuated to make a traditional seltzer. Could you keep it sweeter and still enjoy it? Of course! But I’m not sure how I would classify that style. You’d also need to fine it with something to kill off the yeast, otherwise you are looking at bottle bombs. The simple sugars in hard seltzer are highly fermentable, so yeast will be able to attenuate the brew very well. The FG is going to contribute greatly to the refreshing character of your brew and will work positively with the other factors: effervescence and acidity.

Quality Flavoring Additions

I would highly recommend using your own lime or other citrus zest to create a tincture (or just toss it into the boil). The flavoring I use is locally made and contains only alcohol and zest. Super simple. If you try to use those cheaper flavor extracts it will still turn out okay, but there is something obscenely artificial tasting about them. I personally can vouch for extracts from Horner International based out of Durham, NC. The only ingredients in their extracts are extracts of adjuncts and ethanol. In the case of lime, the only ingredients are “extractives of lime, water, and ethanol (75%). Their extracts make my seltzers taste like I made the extract fresh by hand.

Add your flavoring at kegging or bottling time if using an extract or tincture. If you opt to try zest alone, experiment with tossing it into the boil as well as into secondary fermentation.

Nutrient

Image Credit: (MoreBeer)

You must add nutrient to your seltzer. I have not found a way around this. Will it ferment without it? Yep. But good luck dealing with off flavors, poor performance and terrible attenuation. When we brew beer, malt contributes the necessary nutrients to allow yeast to reproduce, grow and produce alcohol healthily. When we make seltzer, we are simply adding dextrose to water, which has none of those nutrients available. We are mainly talking about Magnesium, Calcium and Nitrogen but we also need other vitamins and minerals:

Vitamins

• Biotin
• Pantothenic acid
• Thiamine (Vitamin B1)
• Riboflavin (Vitamin B2)
• Niacin (Vitamin B3)
• Pyridoxine (Vitamin B6)
• Folic acid
• Cobalamin (Vitamin B12)

Minerals

• Potassium
• Magnesium
• Calcium
• Phosphate
• Sulfate
• Zinc
• Iron
• Copper
• Manganese

Finally, we need trace elements like molybdenum, boron, and nickel.

I have always used Propper Seltzer Nutrient and had fantastic results. If you don’t have a local homebrew shop, grab some here Propper Seltzer Nutrient. I don’t even need to treat my water with salts when I use these. Just add a packet in the last 10 minutes of the boil and call it a day.

Recipe!

Stellar Scream: Lime Rift

ABV: 5.3%

OG: 1.035

FG: 0.995

IBU: 0

Batch Size: 5.5 Gallons

Boil Time: 10 Minutes

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Fermentables:

• 4.25lb Dextrose

Miscellaneous:

• Propper Selter Nutrient
• High Quality Flavor Extract (Lime)

Yeast:

• Kveik Lutra (Dry, No Rehydration)

Water:

• 5 Gallons (Sugar will bring it up to 5.5G)

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1. First, heat the water to 180F
2. Turn off heat and stir in dextrose until dissolved
3. Turn heat on and set target to boiling
4. When boil is reached, add nutrient. You’ll notice the seltzer looks really yellow when you mix the nutrient in, and the finished seltzer will be cloudy. This is completely normal. You can fix this by cold crashing and using a fining like gelatin.
5. Boil for 1Sanitize your chiller as you normally would
6. Chill to 75F and pitch your yeast!
7. If using Lutra, you can ferment hot. Way hotter than you think. I typically run between 85F and 90F.
8. If using flavor extract, add it when packaging your seltzer.

It’s that easy!

Just don’t forget to add acid after fermentation is complete.

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References

Clean Water Gear. “What is Acidic Water?” Image. Accessed September 16, 2023. https://cleanwatergear.com/what-is-acidic-water/#google_vignette.

MoreBeer. (n.d.). Propper Seltzer Yeast Nutrient for Hard Seltzers. [Image]. https://www.morebeer.com/products/propper-seltzer-yeast-nutrient-hard-seltzers.html

Northern Brewer. (n.d.). How to make hard seltzer. [Image]. https://www.northernbrewer.com/blogs/kombucha-and-beyond/how-to-make-hard-seltzer

Savarino, Maggie. “American Effervescence.” Medium. Image. Accessed September 16, 2023. https://medium.com/@maggiesavarino/american-effervescence-4beffb5c644a.