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View Full Version : how do i stop the yeast from fermenting past a certain point?



capoeirista13
09-04-2008, 03:25 PM
Hi all, so I brewed my first mead recently and it is now in the secondary. But I was not expecting how much it would ferment. The yeast ate up allllll my sugar and it lost a lot of sweetness. But I expect it will be good anyway, just not suited to my tastes.

At any rate, I will be making a new batch soon and I want it to not only be sweet, but also to have a low alcohol content. I am looking to make a 5 gallon batch using snowberry honey, vanilla, and brown sugar. My concern is that this will have a lot of sugars in it, but I only want it to ferment to about 6.5% at highest. So how do I stop the yeast from fermenting anymore once they get to this point? And once I've stopped them how do I keep them from starting up again?

wayneb
09-04-2008, 03:38 PM
There is no way to reliably stop a fermentation that is already in progress in order to leave a sweet result with lower than your yeast's alcohol potential, without possibly messing up the mead in the process. Neither chemical methods (sulfite and sorbate) nor environmental methods (such as "cold crashing") work every time with vigorous ongoing fermentations, so the best trick is to mix up a must that will yield the % ABV that you want when it is fermented to dryness. Then stabilize that finished dry mead (using either the sulfite/sorbate stabilization method or repeated cold crashings and racking off of lees - the chemical method is less likely to result in a restarted fermentation) and backsweeten it with enough honey to give the sweetness that you desire in your finished product.

Medsen Fey
09-04-2008, 04:10 PM
A sterile filtration will stop an active fermentation, but it has to be done in a manner that removes essentially all the yeast. If a few slip through, look out.

Wayneb's suggestion is more practical.

capoeirista13
09-04-2008, 04:33 PM
hmm, i see, I hadn't thought of it in that way, thanks big time for the info.

Now, because I don't want a very high %, should I use a yeast that has a low alcohol tolerance, or use the one I was planning on using ( D-47 ) and just give it a limited supply of sugars?

wayneb
09-04-2008, 05:30 PM
If you limit the sugars, then fermentation will naturally stop when the yeast run out of food. Then they will precipitate out of the must, forming a lees layer on the bottom of your fermenter. That's my preferred approach since even yeasts that are advertised as relatively low in ethanol tolerance can often ferment well above their advertised limits, if provided with appropriate nutrients and oxygen at the beginning of fermentation. It is more reliable to stop them exactly where you want them to stop by limiting the sugar that they have to work with. So I'd recommend that you use the yeast you've chosen (I'm assuming that choice was as much for the flavor profile as for the ethanol tolerance, right?) and just give 'em a lightweight must to work with.

capoeirista13
09-04-2008, 06:16 PM
actually I chose D-47 because some people on these boards said it had a 'smooth profile', plus I had 2 extra packs from last time, lol, and I don't know any better : /

wayneb
09-04-2008, 07:00 PM
Sounds like good enough reasons for your second batch to me! :icon_thumright: