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

  • J
    Comment Author: Jeff

    I have a Apple mash 3 pounds rough chopped apples 3 gallons apple juice and topped with water to make 10 Gallon total with 10 pound sugar don’t have a way to check gravity but mash still bubbles after 8 days how do I tell when ready to run been kept in constant 70 degree room since yeast pitched any help appreciated

  • R
    Comment Author: Roger

    This is my second five gallon run and it was week so I was wondering if I could run it again

  • L
    Comment Author: Lee

    My blueberry mash is still working after 10 Days is that alright

  • K
    Comment Author: Ketfeshkellen

    Making 90-130 proof booze 101. If your just starting out Here is the most simple mash recipe out there.
    Step 1: go to the store and pick up 3 to 5 lbs of “dark” brown sugar, active dry yeast, “and if your a city slicker” 5 gallons of spring or purified water.
    Step 2: bust out your biggest pot, throw in at least 3 lbs of your dark brown sugar, all 5 if you like your booze “in this case rum” to be on the warm side and you know how to party. Mix in about 2.5 gallons of water.
    Step 3 bring it to a boil and shutter down about 30 seconds later.
    Step 4: poor it in to your carboy or 5 gallon bucket and poor in the rest of your water. “Hopefully this will help get it cooler quicker”
    Step 6: “very important” wait for your mash to cool down to room temperature
    Step 5: if your mash is cooled down thrown in 1-1.5 table spoons of yeast “I throw in an extremely heaping teaspoon”
    Step 6: find a nice consistently warm around your house or property “preferably not outside” and wait two weeks occasionally giving your mash a whiff to make sure everything is copacetic and up to par.
    Step 7:….. Well considering that I should have told ya how to build a fermentation chamber and added more specific shopping list I’ll have to make this a part two but if ya know how to make a fermentation chamber and can run a still the this was likely to much info for ya but if not then I’ll leave another comment tomorrow on all that

  • J
    Comment Author: Jesus

    In prison my cellie would make 6 water bottles of fire. He used fruit sticks and Mango juice and bread.