how to PERMANENTLY stop fermentation?

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eschatz

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Seriously though, cold crashing is usually how I do it.
I take gravity readings until I get to the point where I want the beer. Then I immediately keg and put in the fridge. Stops the yeast.... cold :mug:
 
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aliu630

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My problem is w/ long term storage. I have some mead in the fridge right now just where I like the sweetness to be, and I'mma end up having to move it out to make room for lagering or other stuff. I also don't have a kegging system. So I'm kind of worried about bottle bombs once temps come back up.I was just curious if there's anything that will kill the yeast and not bring them back to life once temps come back up. Damn these suckers are tough
 

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It's almost impossible to stop a fermentation once it's going. It's like trying to stop a freight train.

What most mead and wine makers do is to let it finish. When it's completely done, completely clear, and ready to bottle, then a campden tablet (one per gallon and crushed) and potassium sorbate is added by racking the mead into it. Wait a few days, then sweeten to taste with sugar, honey, brown sugar, etc. It's easiest to do it if you pull out a sample with a wine thief or turkey baster, and then dissolve the sweetener into that. Add it to the carboy, wait a few days to ensure that fermentation will not restart, and then bottle.

Some have stabilized (added sorbate and sulfite) before allowing it to finish, with mixed results. It's always best to let it finish, so you know that you won't have it restart in the bottle, and then sweeten it.
 

Gordie

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Sterile filtering. 0.5 micron should do it. Otherwise all you can reasonably do is lull them to sleep or kill them sulphur (and wait for the sulphur to dissipate over a few days).
 

beerthirty

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Pasteurize to 160* for 15 minutes in a low O2 environment. Even one living cell can kick off fermentation again. This temp is just below alcohols boil point so it wont drive off alcohol but it is hot enough to kill the yeast.
Edit: not sure how I missed Yoop or Evans post, unless it was that second bottle of pasteurized mead. ;)
 
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aliu630

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It's almost impossible to stop a fermentation once it's going. It's like trying to stop a freight train.

What most mead and wine makers do is to let it finish. When it's completely done, completely clear, and ready to bottle, then a campden tablet (one per gallon and crushed) and potassium sorbate is added by racking the mead into it. Wait a few days, then sweeten to taste with sugar, honey, brown sugar, etc. It's easiest to do it if you pull out a sample with a wine thief or turkey baster, and then dissolve the sweetener into that. Add it to the carboy, wait a few days to ensure that fermentation will not restart, and then bottle.

Some have stabilized (added sorbate and sulfite) before allowing it to finish, with mixed results. It's always best to let it finish, so you know that you won't have it restart in the bottle, and then sweeten it.

I'm confused about campden tablets. I always thought they were used to kill wild yeasts. How does it work against the brewing yeast when fermentation is complete? How come you can only use them after primary fermentation is complete instead of before?
 
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aliu630

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Pasteurize to 160* for 15 minutes in a low O2 environment. Even one living cell can kick off fermentation again. This temp is just below alcohols boil point so it wont drive off alcohol but it is hot enough to kill the yeast.
Edit: not sure how I missed Yoop or Evans post, unless it was that second bottle of pasteurized mead. ;)
Stupid question, so when you say pasteurize at 160* does that mean stick the carboy in the oven? please elaborate :)
 
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aliu630

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So I wiki'd campden tablets and it says
Campden tablets - Wikipedia, the free encyclopedia
Campden tablets are also used towards the end of the fermentation process to halt the ferment before all the available sugars are converted by the yeast, hence controlling the amount of residual sweetness in the final product. This balancing between sweet, dry and tart flavors is part of the artistry of wine and cider making.
There's no source to this so I don't how reliable the information is. Can anyone confirm this or point me in the right direction?
 

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+1 to pasteurize
I think you can pasteurize it at 143F° (60C°) for 1 hour.
To make that you should bottle you mead, put it in your brewing pot WITH WATER, and heat to the desired temperature the water in the brewing pot. Then let it sit for 1 hour. You should reach a bigger temperature, like 160F° and let it sit for 1 hour, to make sure it won't drop below 143.

Since it's mead, i dont think you will carb it, because your yeasts friends will be dead.
 

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Although stopping fermentation mid-way might prove difficult, there are a few steps you can take that will increase your chances:

1) You say that you have it in the fridge. The yeast should be flocculating by now. If so, you should rack into a carboy, to get rid of the yeast cake that is forming (some of that yeast might be reactivated when it gets warmer).

2) Indifferent of the flocculation, you should add Potassium sorbate and Metabisulfite. The dosage is about 1 tsp. potassium sorbate and 1/4 tsp. metabisulfite for 6 gallons. The Sorbate will zap the yeast dead (that's why for things like Apfelwein, you musn't have sorbate in the apple juice) and the sulfite will kill wild yeasts and other bacteria as well as preventing oxydation. You should add this to about 1/2 cup of cold water, stir well, then add to the mead and stir again.
This should hopefully stop fermentation, especially if the mead is already cold (many stress factors on the yeast).

Forget about pasteurizing. You will get rid of most of the alcohol, and the burned yeast can give a weird taste.
 

seewala

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I agree with mrfocus,

I have made a number of scratch wines as well, when you are ready, keep your mead cold, rack and add the potassium sorbate and k-meta in the dose he recommends.

You can never really 'kill' yeast, the the metabisulfite stuns the yeast, and the sorbate acts like birth control so any yeast left in the mix can't start up again.

Most LHBS will sell a 'stabilizer', that is premeasured sorbate and sulfite for a 5 gallon batch.
 

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So I wiki'd campden tablets and it says
Campden tablets - Wikipedia, the free encyclopedia


There's no source to this so I don't how reliable the information is. Can anyone confirm this or point me in the right direction?
That's not completely correct. I use campden (potassium metabisulfite) before, during and after fermentation in my wines and meads. It does sanitize the must, killing wild yeast and bacteria. Then, I add yeast and allow fermentation. The reason that this works is that brewer's yeast tends to not be as susceptible to campden- that's why we use sulfites to keep away the bad yeast and bacteria but can use wine yeast. I like to keep my sulfite level at around 50 ppm, which is below the taste threshold but also protective of the wine.

You can't bank on sulfites to "kill yeast" in wine or mead. You can't bank on sorbate to do it either. But together, they keep yeast from reproducing. So, that usually means fermentation doesn't restart once it's finished and the sorbate and campden are added. The remaining yeast are alive, but not able to reproduce.

That's why it's hard to stop a fermentation with it- there are still plenty of yeast to do the job. But if you wait until it's done, and rack off of the lees onto the stabilizers, you have a pretty good chance of it not restarting.

I imaging the pasteurization mentioned above would work. I would never subject my hard work (keeping the mead at a controlled temperature, fining it to clear it, etc) to heat, though. I think the flavor of mead and wine can be very delicate and I think that even a low temperature of 160 degrees would impact it.
 

CBBaron

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Once you have stopped fermentation by cold crashing you can prevent renewed fermentation by adding potassium sorbate AND campden tablets. As Yooper mentions this combination prevents renewed fermentation but probably will not stop and healthy ferment.
You can also get a sweet mead by waiting until the mead ferments dry then adding the sorbate and campden and back-sweetening to the desired sweetness.

Craig
 
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aliu630

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I think I will try pasteurizing 1/2 my mead and trying out some of the potassium sorbate and campden tablets. I only have 1 gal to mess around w/ so not too big of a deal. Thanks for the help guys/gals
 

Bigsnake

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Seriously though, cold crashing is usually how I do it.
I take gravity readings until I get to the point where I want the beer. Then I immediately keg and put in the fridge. Stops the yeast.... cold :mug:
With cold crashing, isn't there still some yeast left suspended in the beer? Then it could still start fermenting again if brought up to room temperature, assuming there was sugar in there for the yeasties.
 

chardo

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In the past I have when dryness/sweetness level was to my liking. I would bottle and wait until the carbonation was right and then run the bottles through the dishwasher to pasteurize them. The normal and hot dry settings worked well on my old dishwasher. Check the times and temps to get the timing right.
Chardo
 
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