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Robintun
06-21-2008, 10:58 PM
I do not know anyone who makes mead or brews, but I was chatting with this guy and mentioned I was making my first batch of mead when he said he brews beer. During our conversation he mentioned that you can re-use yeast and even "grow" it stronger with subsequent generations. I looked through my books, did a bit of searching on the internet and put a few searches on the site here and have not come up with much of anything. Is this something that can be done or is it only with beer yeast? He seems to rack differently than what I have read though. He made it sound like the first racking has nothing in the lees I would want, the second drops out dormant yeast and he racks at least one more time after that and there is very little if any yeast left at that point. I do not know how good of a brewer this guy is so maybe he was just feeding me a line.

Oskaar
06-21-2008, 11:51 PM
Yes you can re-use your yeast ... if you have the proper equipment to do so. This means knowing how to harvest the yeast at optimum growth time and growing colonies on selective growth media in order to isolate out any spoilage flora. Once done you have several other steps necessary to ensure you are breeding a healthy, virulent strain of yeast that you can propagate. Other equipment necessary includes, a good microscope, yeast growth slants, incubator, petrie dishes with agar for colony counts and streaking, etc. There's a lot of stuff necessary to do it right. Yes, beer yeast cake can be taken right off the ferment after rack and used to fire up another batch. Different environment with different results for the yeast.

For the average meadmaker it is simpler, more cost effective and time effective to spend the $3 to buy two packs of active dry yeast, rehydrate it properly and pitch it.

Hope that helps,

Oskaar

vahan
06-22-2008, 05:43 PM
Oskaar is of course right, as usual!

If you're making beer, it nice to "re-use" yeast (the $8 liquid kind). I recently made a batch of belgian wit and made another batch my racking right onto the yeast that had settled into the primary. It worked so well my airlock exploded and yeast spewed all over the place. I wouldn't go more that 2 batches with beer b/c of the possibilities of contamination, mutation, etc (and you'd be brewing beer weekly--which is fine if you're a professional brewer, but not practical if you're a homebrewer).

With dry wine yeast for mead, it is sooooo much easier to just buy some more packets....

happy drinking,
vahan

Robintun
06-23-2008, 01:23 PM
Thanks, is what I needed to know - not worth it at this stage.

But you are the second person Oskaar I have noticed mentioning using 2 packets of yeast. My first batch I only put one in. It said it was good to 5 gallons and a week later still seems to be bubbling along ok as best I can tell - 1 big bubble from a tree-piece airlock every 4-6 seconds which is what it has done since the first day. Of course from my recipe here (http://www.gotmead.com/smf/index.php?topic=6956.0) you can see I "accidentally" had to make a bit of a starter for the first 12 hours so maybe that is why it is doing ok? Is it always better to do 2 packets or will making a starter suffice? It is only an extra buck to use 2, but just curious.

wayneb
06-23-2008, 01:59 PM
I can chime in on that one. Yeast will take a little time to get acclimated to the new, nutrient rich environment of the must (the lag phase) and will undergo a certain number of replication cycles (the exponential growth phase) on the way to establishing a stable colony in your must. The more you pitch up front, the fewer cycles will be needed to get up to where it needs to be to support vigorous fermentation. For the most part, the yeast available in one 5 g packet of active dry culture will be more than enough to get a healthy colony in a 5 gallon batch established pretty quickly. But in some special cases where it will take the yeast an exceptionally long time to develop (say, in a must with an exceptionally high starting gravity), it can help the yeast to get a quicker foothold when you pitch a greater amount to begin with. So in those cases it is a good idea to pitch two, or even three, packs of dry yeast.

Oskaar
06-23-2008, 02:56 PM
Wayne is on the button with what he said. Standard protocol for pitching is one package for musts under 26 brix, two packets for musts equal to or above 26.

Cheers,

Oskaar

andrewschwab
10-07-2009, 11:51 PM
This is killing me, was searching for a way to reuse a native wine yeast that is currently going as I type.

This is a gamay noir pyment, no yeast added, just who was hitching on the grapes. For now it is looking good.

BUT alas, I was hoping to repitch what settles out on the bottom, to try in a traditional mead, to see what results it would give. It sounds as if this won't work. ugggg or could it :rolleyes:

Oskaar
10-08-2009, 12:07 AM
Try propagating a new batch of about a quart of must or so. Once the lag phase is ended, and the yeast are really kicking up a kerfuffle, take the dense layer of yeast from about an inch below the bubbling surface of the must and plate it out, or put it into a slant or other similar media.

You should be able to propagate that up to a usable strain.

Cheers,

Oskaar

wayneb
10-08-2009, 08:50 AM
Like Oskaar said, the key is to snag the yeast that you want to propagate before it gets too far along in the fermentation of the batch that you're harvesting from. As long as you grab it while the fermentation is still vigorous, you'll preserve a pure strain of that native yeast. Once fermentation has been underway long enough for the ethanol concentration in the must to get high enough, those yeast that are still viable in that heavily alcoholic environment have undergone mutations to adapt to the toxic mix and so are no longer your desired native strain. Sometimes those changes are benign, sometimes they can actually result in a yeast that performs better than the original, but in the vast majority of cases the changes will be for the worse.

Beer is a different animal, since the ETOH concentration in most brews doesn't get up to the point where the yeast are so stressed that they mutate to adapt.

andrewschwab
10-08-2009, 09:52 AM
Ahhhh SNAP, already at the 1/2 break, plus the other buckets have things going on in them also. Like a blueberry, and another pyment with rc212.

Next year, will need to think something up. So as to be able to use the yeast without running a full pyment, maybe a quart jar starter with grapes then poor that into a 5-6 gallon must???

thanks for the info, saved me from wasting some honey... :cool:

wayneb
10-08-2009, 10:07 AM
Yup - the quart jar thing should work for you. I'd suggest doing a couple of things to ensure that the yeast you're getting is the yeast that you want. First, I'd do the quart jar of crushed grapes. Then, when fermentation is in the early active phase, pull off a sample (maybe about a cup) from just under the cap, as Oskaar suggested. Let the rest of the quart ferment quietly in a corner while you use that cup as a starter seed into another quart, this time perhaps with some grapes and honey. As soon as that batch is in the early active phase, repeat the process with another quart and some fresh grapes/honey/water. This way you're doing a liquid culture of the strain, and after you've done this for several iterations, you'll have a starter ready to pour into a main batch, and the first quart will have fermented down to the point where a taste or two from that batch will tell you if this is a yeast that you actually want to use in a larger batch.

The culturing of yeast in a dish or a slant tube of nutrient media may or may not be something that you're ready to try (depends on how much you enjoyed high school biology class, I think), but this simple "liquid culture propagation" technique is fairly straightforward for anyone who has already done a batch or three of their own mead.

andrewschwab
10-08-2009, 11:43 PM
Thanks for the suggestion/information. That sounds like a good plan.


The culturing of yeast in a dish or a slant tube of nutrient media may or may not be something that you're ready to try (depends on how much you enjoyed high school biology class, I think), but this simple "liquid culture propagation" technique is fairly straightforward for anyone who has already done a batch or three of their own mead.

A, ya, that is a bit to much for me at this time. I don't have enough time or space. Family, kids, bees, work etc... all pulling for there share of time..

But the quart thing sounds like a plan... Someone pull this thread back up come next year Mid Sept... ;) Cause if I print it I will loose it.

Cuchulain
04-20-2010, 10:42 PM
I wonder whether this is one of those "received method" issues which people just take as read and don't bother testing.

I figured I'd check it out a bit. Wine yeast has a higher tolerance to alcohol than beer yeast, so it shouldn't be as stressed as people say, so long as it hasn't come from a nutrient-poor must.

What I can say from my own experiment: Premier Cuvee yeast, harvested from a very tasty pyment, makes a very tasty show mead. No traces so far of off flavours - in fact it's one of my most successful batches ever. I just racked it off 2 nights ago into several different bottles (2 melomel, 2 show mead 5L bottles) and I've once again harvested the yeast (a cup or so of boiled/cooled water, swish it up, chuck it all in the fridge for half an hour, decant off the suspeded yeast.) It's sitting in my fridge ready for my next batch.

Keep watching for updates.

AToE
04-21-2010, 01:40 AM
I figured I'd check it out a bit. Wine yeast has a higher tolerance to alcohol than beer yeast, so it shouldn't be as stressed as people say, so long as it hasn't come from a nutrient-poor must.



Not at all to discourage any experimentation but I thought I'd point out a flaw in the logic of this paragraph - while yes, wine yeasts have higher tolerances of alcohol, they are almost always pushed to or past their expected tolerance, or at the very least fairly close.

Beer yeasts, while having a much lower tolerance are (from my understanding) almost never pushed anywhere near their tolerances, and as such the stress on them would be less.

My logic would be that the tolerance doesn't matter, it's how that tolerance is pushed that matters.

akueck
04-21-2010, 01:47 AM
Most beer yeasts will ferment to 12% abv or higher given the chance. The perception that they have a lower tolerance is probably caused by the fact that beer yeasts come with an "apparent attenuation" number, but that has a lot to do with the complexity of a beer wort and somewhat less to do with the yeast itself.

You may or may not see off-flavors produced by repitched yeast. You may luck out and get great performance, or you may get rotgut. The thing about repitching yeast, and especially yeast that has been worked to its limits, is that the performance the second time around will be different. Different can be good, or different can be bad. It's a crap-shoot. If you've stumbled on a good bounce, excellent! Ride it out and see where it takes you.

Cuchulain
04-21-2010, 07:08 AM
Well, yes, if I'd pushed it, that would be a problem. But I'm well within the tolerance level - I've been quite kind to the little yeasties. The way I figured it was that the "sweet mead" and "dry mead" yeasts had to come from somewhere - probably from some enterprising chap willing to take a particular strain through a few generations of meads. Why not do the same? As you say, see where it takes me. Seems to be working pretty well so far.

Cuchulain
04-21-2010, 07:29 AM
To take the logic down a different path: I always make a good starter with my yeast, even with the volume of yeast you get by harvesting. It just makes sense to proof your yeast before pitching, make sure everything is healthy and is up to speed.

So: We have the genetic material, enough viable cells which have been fed up on a decent nutrient mix for a day or so. Even if the yeast had been stressed at the end of the last fermentation, by the time they've gone through their starter, they're up to full health again. So the remaining danger comes merely from the possibility of genetic mutation. Actually, I don't fear that. I reckon it's just as likely to get a better flavour profile as a worse one, and the change is probably going to be pretty gradual at that.

So. More experimentation required. I would welcome other people's experimentations and experience as well, if anyone has tried it.

AToE
04-21-2010, 12:21 PM
To be honest, dispite that I feel pretty confident that there's a high chance of less that great results, this is definitely an experiment on my long-term to-do list. I'll probably do 1 gal batches and just see where it goes, it'd be kinda fun too have my own personal strain if it mutates in a good way (or more likely that it mutates into junk, but whatever, that's what experiments are for). :)

Angelic Alchemist
04-21-2010, 12:21 PM
Make a starter out of the old yeast. If the starter smells awful after 24-48 hours, toss it and use new yeast.

Medsen Fey
04-21-2010, 03:32 PM
Unless you let the yeast go through cycles of sporulation and sexual reproduction the strain will indeed mutate, and may lose vigor. Also, as you harvest from the lees, or from the active fermentation, you may get increasing amounts of bacteria going along for the ride. It will probably result in your own "mixed house-culture" that will be unique to your brewery/winery/meadery. It may be good.

As homeys, we can take that risk. If I spoil a 5 gallon batch, its no big deal. If I had a couple of 1000-gallon fermentation tanks and my livelihood depended on it, there's no way I take that chance. A few cents per gallon to have fresh, predictable yeast is a small price for insurance.