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Paladin906
08-23-2015, 09:04 PM
Hi All,

Is there any way to stop an active fermentation without cold crashing? For my next batch I want to attempt an ABV of 12% but I wanna use a yeast strain that has a much higher alcohol tolerance. Also, is there a yeast strain that has a 10-12% tolerance?

Squatchy
08-23-2015, 10:25 PM
It's always a gamble as to whether one can stop an active fermentation at all. Cold crashing is no guarantee and neither sulfite/sorbates. Why do you want to use a yeast with a much higher tolerance level than what you need. Makes little sense to me. You can look at the manufactures web sites and find what the alcohol tolerances are. Lalvin 71-b is a 14%, but just because it says a certain limit doesn't insure it will stop there either.

http://www.lallemandwine.com/

bernardsmith
08-24-2015, 11:39 AM
Just thinking aloud here but if yeast die if the temperature is too high (eg 130F - 140 F might it be possible to stop all yeast activity if the batch was heated to say 135 F . Would such heat be enough to destroy volatile aromatics or set pectins?

EJM3
08-24-2015, 12:08 PM
I think that is getting into the realm of Madeira or Sherry making temperatures, don't quote me on that one, I think that Medsen has experience with those techniques...

As for stopping an active ferment, I've never been able to, on purpose that is. I've made a goof & dropped the pH to something ridiculous like 2, I used it as an "alcoholic vinegar". I tried cold crashing & the little basetards chomped another 15 points before finally giving up.

About the only effective method is to cold crash first, then rack onto sulfite & sorbate. I usually had to cold crash for an average of 2 weeks to get my crystal clear, YMMV...

Paladin906
08-24-2015, 11:24 PM
It's always a gamble as to whether one can stop an active fermentation at all. Cold crashing is no guarantee and neither sulfite/sorbates. Why do you want to use a yeast with a much higher tolerance level than what you need. Makes little sense to me. You can look at the manufactures web sites and find what the alcohol tolerances are. Lalvin 71-b is a 14%, but just because it says a certain limit doesn't insure it will stop there either.

http://www.lallemandwine.com/

I've had good results with EC 1118 and I want to stick with it but I don't want an abv of 19% this time. I like the result i got by letting the yeast die at its tolerance. I had an awesome batch that eventually went bad after cold crashing. I honestly don't know if the cold crash caused it to go bad but would like to avoid it if there are other options.

Squatchy
08-24-2015, 11:43 PM
I certainty don't know everything by any stretch, but I'm sitting here thinking to myself and I cannot think of how, or why would cold crashing ruin a batch. Tell us about your ordeal and maybe we can figure something out

Maylar
08-25-2015, 01:45 PM
Some ale yeasts finish in that range. Nottingham is about 12% and S-04 is 10-12%

EJM3
08-25-2015, 03:45 PM
When you cold crash the air inside of your carboy shrinks & sucks the air from your refrigerator into it, if you have mold or other contaminants those will be sucked into the carboy. To prevent this from happening to my batches I usually fill the airlock with fresh vodka so as to kill any possible infection organisms. Also if you have a large amount of head space it will suck in large amounts of air, with oxygen it it, that will then oxidize your mead, so minimize head space before you cold crash, if possible.

Paladin906
08-25-2015, 09:32 PM
I don't have the science to explain what exactly happened. All I can tell you is that my ferment was slowing but still active. It had reached the SG I desired so I cold crashed. I put it in the fridge for two weeks. My must had a spectacular taste before the cold crash but a week after taking it out of the fridge, there was a noticeable difference in taste that got progressively worst.

I did have an airlock on the carboy filled with vodka but I also had a moderate amount of head space. This was a two gallon batch. My next batch will be a 5 gallon so the next question is how do you even cold crash a 5 gallon batch? My fridge isn't that big.

Paladin906
08-25-2015, 11:39 PM
Some ale yeasts finish in that range. Nottingham is about 12% and S-04 is 10-12%

Do you have any experience with these strains for mead?

Squatchy
08-25-2015, 11:43 PM
I live in Colorado and do most of my fermenting during the winter. It's easy for me to put it on the front porch in the winter to cold crash it.

GntlKnigt1
08-26-2015, 12:05 AM
I cold crash on patio here, which isn't a problem for me, but for someone like JD Webb is southern California, it would be. Temp has to get well below the active fermentation temp for a week or more, and I stabilize the batch with 1/8 tsp (440 mg) potassium metabisulfite per gallon and tsp (1 gram) potassium sorbate per gallon, especially if I am planning on backsweetening at some future time. Success with doing that depends, in some measure, on the yeast used, according to Oskaar. Off tastes after 2 weeks in frig could be the result of stressed yeast as much as possible contamination.

curgoth
08-26-2015, 10:03 AM
Being in Toronto, I cold crash on my balcony in winter, though I have to keep an eye on the temperature to make sure I don't freeze it.

bernardsmith
08-26-2015, 10:28 AM
I don't have the science to explain what exactly happened. All I can tell you is that my ferment was slowing but still active. It had reached the SG I desired so I cold crashed. I put it in the fridge for two weeks. My must had a spectacular taste before the cold crash but a week after taking it out of the fridge, there was a noticeable difference in taste that got progressively worst....

.

What was the difference in taste and what do you mean when you say that it got progressively worse? How did you sample the mead to taste it (from the top of the container or from the bottom)?

Paladin906
08-26-2015, 06:22 PM
What was the difference in taste and what do you mean when you say that it got progressively worse? How did you sample the mead to taste it (from the top of the container or from the bottom)?

It developed a sour taste that was mild and progressively became pronounced. The samples were taken when I'd rack at first then I used a sterile baster at times to draw samples from the middle.

kudapucat
09-02-2015, 07:02 PM
Cold Crashing then chemical stabilisation
Alcohol stabilisation (fortify it with spirit) I'd still get it cold to make it hold better.
Pasteurisation - (I wouldn't be too happy with what I think might happen - cooking changes the taste of most everything)

These are about the only options out there.
Temperature poses a risk, you need sudden and sharp temperature changes, or the yeast will try to adapt and may throw strange flavours as they go to sleep or die.