Hard Seltzer Base- 23L batch

Hydrometer reading-

Starting gravity:                    1.042

Final gravity:                          around 1.000   
Estimated ABV:                      5.5%

6 lb/2.72 kg Dextrose
2 g Potassium Bicarbonate
23 g Fermaid O, divided: 9 g, 7 g, 7 g (100 g/hL)
7 g GoFerm Yeast Rehydration Nutrient (30 g/hL)
1 x 5g Premier Cuvee Yeast


Distilled or Reverse Osmosis (RO) water is recommended to avoid cloudiness and off-flavours.

Prepare Sugar Solution
Heat 8L of distilled/RO water. While heating, add dextrose and potassium bicarbonate to the brew kettle and stir until dissolved. Bring to a boil for 5 minutes to ensure sanitary conditions.  Add 9 g Fermaid O and boil for 5 minutes longer. Cool the sugar solution.


Fill primary fermenter with 8L of cold water, then pour in the cooled sugar solution. Add more cold water (about 7L or an amount needed to bring the volume up to 23L.
For pitching the yeast, the temperature of the sugar solution should be 20-25°C.


Rehydrate Yeast
Dissolve 7 g GoFerm in 140mL hot water (> 80°C) and then cool to 35-40°C.
Add 5 g Premier Cuvee to the rehydrated GoFerm and stir gently.
Wait 20 minutes, stir again and then pitch yeast into sugar wort.

Ferment at 20-25° C
About 24 hours after start of fermentation, add 7g Fermaid O.
About 48 hours after start of fermentation, add 7g Fermaid O.
Adding yeast nutrients in staggered additions ensures that the yeast remain happy and healthy and will avoid any off-flavors that stressed out yeast can generate.

If fermentation seems to stall, it’s likely because the pH has become too low. You may need to make a small addition (1-2g) of potassium bicarbonate.

When fermentation is finished, add finings to clear. Filter if you feel it’s needed.

Add fruit flavouring to taste.

Force carbonate in a keg, or prime with dextrose or Cooper’s Drops to carbonate in bottles.

If you are going to force-carbonate in a keg, you can “scrub” with CO2 after transferring off yeast, to drive any lingering yeast characteristics out. Those can include sulfur, DMS, and other compounds that might hide in beer but are all too noticeable in seltzer.

How to do it:

With the seltzer in a keg and the lid removed, connect a gas line (set to about 3–4 psi or 0.2–0.3 bar) to the “out” post and simply bubble gas up through liquid for five minutes. Then replace the lid and carbonate as usual.

And enjoy!

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