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gron151
10-13-2010, 08:43 AM
For some of my wines i have placed the wine in a fridge/freezer and bought the temp to a point where the wine would almost freeze with the alcohol thatís less than 32f. This has killed out the yeast without having to use any preservatives. Anyone know if this works with Meads as well or is there any chance I might rune the batch?

chiguire
10-13-2010, 10:21 AM
My worry would be that instead of killing the yeast, you would just make them go dormant, only to have them wake up when the environment warmed up. But, I am sure someone else will chime in with better information.

I have heard of cold crashing to try and help clear the mead/wine/beer, but I have not heard of it used to definitively kill the yeast.

gron151
10-13-2010, 10:35 AM
Its worked well with my wines. The idea is to leave it at just above where it would freeze for a few weeks. I have even back sweetend a few wines and use this method. It has been over a year since they were bottled and no popped corks yet.

Chevette Girl
10-13-2010, 10:46 AM
For some of my wines i have placed the wine in a fridge/freezer and bought the temp to a point where the wine would almost freeze with the alcohol thatís less than 32f. This has killed out the yeast without having to use any preservatives. Anyone know if this works with Meads as well or is there any chance I might rune the batch?

You won't ruin the batch by chilling it, there are a few people who use cold-crashing to halt yeast but I think they generally add chemicals afterwards just to make sure.

wayneb
10-13-2010, 01:55 PM
My worry would be that instead of killing the yeast, you would just make them go dormant, only to have them wake up when the environment warmed up. But, I am sure someone else will chime in with better information.

I have heard of cold crashing to try and help clear the mead/wine/beer, but I have not heard of it used to definitively kill the yeast.
This can indeed happen. Cold crashing, even at temperatures hovering around freezing, and even if done for weeks at a time, may only cause the yeast to go dormant and they can in fact wake back up and begin to ferment again.

Generally the folks who have had success with bottling cold crashed meads with residual sugar have also been very careful about racking the finished mead off of its lees. Dormant yeast are slightly more dense than water, and they will precipitate out of cold crashed wines. So if you are careful about racking you may be able to leave enough of them behind that you don't get enough viable cells to build back up to a colony size that can do significant refermentation once the mead is warmed back up.

However that is a chancy proposition, and while it might work most of the time for some folks, there will likely come a time when too many recently re-awakened yeast do come along for the ride into bottles, and then bottle bombs are the inevitable result. As CG said earlier, most people who stop fermentation by cold crashing also ensure that it stays stopped by adding a little sulphite and sorbate to the racked mead before bottling.

Medsen Fey
10-13-2010, 02:25 PM
This also will vary from yeast to yeast, and will be impacted by things like how close you are to the alcohol tolerance of the yeast. If you are very near the tolerance, it might be enough to keep them suppressed when they warm up. I don't think I'd be trying this with EC-1118. It is worth remembering that some high-ABV yeast can appear dormant for a long time then reawaken up to two years later.

I would not recommend cold crashing as the only step for stabilizing any fermentation.

YogiBearMead726
10-15-2010, 11:31 AM
This also will vary from yeast to yeast, and will be impacted by things like how close you are to the alcohol tolerance of the yeast. If you are very near the tolerance, it might be enough to keep them suppressed when they warm up. I don't think I'd be trying this with EC-1118. It is worth remembering that some high-ABV yeast can appear dormant for a long time then reawaken up to two years later.

I would not recommend cold crashing as the only step for stabilizing any fermentation.

Speaking from experience with EC-1118, I decided to decant my "racking losses" so that I could try some of my tomato-basil mead by throwing it in the fridge (~40-45 F). For the next week or so, there was still activity going on, despite the less than ideal temp conditions. All in all, cold crashing seems like a dangerous game to play if it's all you rely on.

allyouneedismead
08-16-2016, 12:29 PM
could it be filtered instead of using chemicals to remove both yeast and bacteria?

bernardsmith
08-16-2016, 02:08 PM
Short answer - yes, but to filter your mead really must be bright clear - that is to say with absolutely no particles floating in the mead. Any particles will quickly clog the filter. So if you cannot read the fine print of a document through the bottle and if reading through your mead is not like reading through clean glass then filtration may not be your best bet.