How to Know When Fermentation Has Finished

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Portrait of Emmet Leahy

Emmet Leahy is the Chief Operating Officer and lead product developer at Clawhammer Supply, a small scale distillation and brewing equipment company. He loves the process of developing new equipment for making beer at home just as much as he does using it to brew his own beer. He's also passionate about teaching people how to use distillation equipment to produce distilled water, essential oils, and with the proper permits, fuel alcohol and distilled spirits.

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96 Comments

  • RS
    Comment Author: Rob Stark

    Your followers have great questions. Several I would love to see your expertise and opinions concerning your solutions / answers.

    Washington State Shiner

  • K
    Comment Author: kevin

    i forgot to add a step to the 5+5+5 recipe i posted. finally after getting your mash going by pitching the yeast (DADY yeast), top off the five gallon fermenting bucket with water at a temperature of 80+/-10 degrees f, then cap it off.

  • K
    Comment Author: Kevin

    heres a simple recipe, using the “5+5+5 method.” for fermenting in a 5 gallon bucket, bring 3 gallons water to a boil, add 5 pounds of granulated sugar, stir til the sugar is dissolved and the water is clear. turn down the heat, slowly add 5 pounds of corn meal, stirring constantly, stir for a while. turn off the heat, let the mixture cool til its temperature is about 150F. add amylase enzyme, stir for a few more minutes and let it sit for an hour or twq. put the mixture in your fermenter, let it cool til no warmer than 100F. add yeast nutrient according to directions. a can of tomato paste with no additives works instead of fancy nutrient. throw your yeast in there, stir it up. cap it off. i usuall wait until my mash is totally done bubblimg in the airlock before i figure its ready. syphon out the clear stuff, get rid of the mud at the bottom and there ya go. drink as is or do whatever you wanna do with it.

  • D
    Comment Author: DAno

    Thanks for all the info. Is there a chRt- formula for how much water to how much solids- such as sugar- corn /corn meal- etc?

    Thanks Dano

  • T
    Comment Author: Tim

    Are there answers to the questions ppl post?
    q: My mash is going passed 3rd wk of fermenting. I still get the water pushed to the other side in my airlock (bbl’s too slow to watch, but it’s still working).
    Is my mash going to turn to vinegar? I used 20lbs of corn sugar to make 5 gals. The S.G. hasn’t changed (started at 1.150, went to 1.012 & staying) but it’s still giving off Co2. I’m afraid if I wait too long, it’ll turn to vinegar.
    Should I just go ahead & run it, while it’s still giving off Co2? Or wait until no more Co2, & risk it turning? Please help!