Yeast Harvesting from Starter

[Otto Von Blotto]

I have a bit of a volcano on the kitchen bench currently. This 1469 yeast went mental!

 

[BeakedRiot]

Am I correct in thinking that the yeast harvested from a starter deteriorates (pretty quickly) once stored in the fridge, just like store bought liquid yeast does?

 

My understanding is that you use a yeast calculator to determine the viability of the yeast based on the date it was harvested, but after playing around with the numbers it looks like if you harvest 135 billion cells (like your last example) you would only get a few months before likely needing a step-up starter.

 

Is there any reliable option for more long term storage?

[Otto Von Blotto]

I'm led to believe the same thing, which is why I only keep 3 strains for regular use. I have stepped them up in the past if they've been left in the fridge for a while, depends on the estimated viability of the calculator.

 

I have read a couple of low-key experiments that appear to show that the rate of viability decrease isn't as fast as the yeast calculators would suggest, however it's probably better to be conservative anyway, so I just go by the calculator.

 

If you want to store it long term it can be frozen in a glycerine solution, or look up yeast slants. These have to be built up in multi-stepped starters prior to use in a batch as they only save a small amount of yeast.

[Dickster86]

Really want to start getting into better yeast management for lack of a better word.

 

I have started rehydrating all of my yeasts as a rule, and typically dont use kit yeasts anymore. But would be keen to get into starters.

 

Is there any real point if using dry yeast though? or is this more for liquid yeast?

[Otto Von Blotto]

Depends on the dry yeast - and your reasoning for making a starter from it. If it's simply to pitch it into the batch, then there probably isn't a lot of point making a starter*. If you're planning on re-using it a number of times then I think it's worth the effort even though dry yeast isn't all that costly. I'm up to about 10 generations on a pack of US-05 I bought about a year ago, that's about $50 worth of yeast I've not had to buy.

 

*For lager yeast rather than waste a heap of money buying 2 or 3 packets of it, or use the pitch warm and bring down to temp later method, I prefer to make a starter with it because it costs more than ale yeast and I prefer to pitch as close to ferment temp as possible.

[Dickster86]

Yeah a bit of both i suppose. Being able to re-use the same yeast multiple times. But also just making sure i am pitching enough viable cells.

 

And when i do get on to making lagers properly with temp control and all that jazz then i would be wanting to pitch at low temperature, and from what i understand from your other posts that means i am going to need a lot more cells.

 

Plus in the future id like to move on to liquid yeasts so some practice first will be handy

[Otto Von Blotto]

Yeah a bit of both i suppose. Being able to re-use the same yeast multiple times. But also just making sure i am pitching enough viable cells.

 

And when i do get on to making lagers properly with temp control and all that jazz then i would be wanting to pitch at low temperature' date=' and from what i understand from your other posts that means i am going to need a lot more cells.

 

Plus in the future id like to move on to liquid yeasts so some practice first will be handy[/quote']

 

Both are very good reasons for making starters. I've had great success with this method since I began using it early last year. I was making starters before that but I never even thought to harvest directly from them until I read it on Brulosophy.

 

It's only my opinion but I think lagers turn out nicer if pitched low rather than pitching warm and bringing it down after a day or whatever. That's why they need about double the pitch rate of ales. Most of my lagers need around 450 billion cells pitched, whereas my ales are more around 200-220 billion.

[Dickster86]

Yeah because say i use a us-05, according to the spec sheet it has 6 x 10^9 viable cells per gram, thats only 69 billion cells in an 11.5 gram pack. But if i look at yeastcalc it says for a 25L ale with OG of 1.050 i need 232 billion. So definitely a massive under pitch.

 

Regarding lagers that totally makes sense to me. I like the idea of pitching at ferment temp, not pitching then cooling. That early stress stage cant do any favours to off flavours

[Petermur]

The simplest method of all is just dumping a new batch on top of an old yeast cake. This negates the need for cleaning out the FV between batches' date=' and you have a heap of yeast which gets to work in record time usually. Of course, you still get all the rubbish in the yeast, and while I have done this occasionally, it's usually only been when the new batch is similar to the old batch, or it's something like a porter going in after a pale ale. It's probably more suited to AGers who don't have to mix up ingredients in the FV like kits/extracts do.

 

But now that I have been made aware of this harvesting from the starter method, thanks to Ben 10's link in one of the brew day threads, I can have clean yeast for every batch and I probably won't be doing the new-batch-onto-old-cake method much again, if at all. I certainly won't be mucking around with rinsing anymore. [img']lol[/img]

 

Cheers

 

Kelsey

 

Hi Mr Von Blotto,

Can you tell me more about this "Simplest Method" - are you saying that after bottling, I can start a new batch of brew by mixing a kit and kilo, or extract wort, straight into the now mostly empty FV and pouring it onto the trub (which I normally throw away and clean my FV).

In other words, can a new batch be made more than once without using new dry yeast or cleaning the FV.

I currently do extracts and use a new US05 each time and I'm OK with this, but I'm intrigued with the simple method.

Can you give a few tips on this way - how is cloudiness, taste, etc.

Thanks, Peter.

[Beerlust]

Hi Dickster86.

Yeah because say i use a us-05' date=' according to the spec sheet it has 6 x 10^9 viable cells per gram, thats only 69 billion cells in an 11.5 gram pack. But if i look at yeastcalc it says for a 25L ale with OG of 1.050 i need 232 billion. So definitely a massive under pitch.[/quote']

Not true.

 

You're missing one very important symbol from the US-05 spec sheet on the viable cell count per gram, that being ">" at the beginning.

 

It should read "...Viable cells at packaging: > 6 x 10^9/g". That means greater than that number of yeast cells.

 

Jamil Zainasheff (co-author of the book "Yeast - The Practical Guide To Beer Fermentation") confirmed sometime back on a Brewing Network podcast that Clayton Cone (a Lallemand based yeast expert) said dry yeast has 20 billion cells/gram. He also says all of the tests he has done (i.e. cell counts after proper rehydration) show around 20 billion cells/gram. He offers the explanation that the yeast makers probably hedge their bets to account for poor storage and poor pitching technique (i.e. sprinkling on wort without rehydration) when giving the value of 6 billion cells/gram.

 

What you have in that single sachet of US-05 yeast is something a lot closer to 230 billion yeast cells, not 69 billion.

 

In the case of your brew, I'd be more inclined to scale back your volume from 25 litres to 21-23 litres @ the same 1.050 OG as you are certainly on the limits for a successful fermentation if using a single sachet of dry yeast in that configuration. That, or you can of course attempt to increase your starting volume of yeast cells through making a starter.

 

On a personal note I am still not convinced about what volume of yeast cells are actually required to adequately ferment out brews successfully, but do agree it is better to overpitch rather than underpitch.

 

Cheers,

 

Lusty.

[Otto Von Blotto]

Yeah because say i use a us-05' date=' according to the spec sheet it has 6 x 10^9 viable cells per gram, thats only 69 billion cells in an 11.5 gram pack. But if i look at yeastcalc it says for a 25L ale with OG of 1.050 i need 232 billion. So definitely a massive under pitch.

 

Regarding lagers that totally makes sense to me. I like the idea of pitching at ferment temp, not pitching then cooling. That early stress stage cant do any favours to off flavours[/quote']

 

Yes, Lusty is right there about it being a minimum of 69 billion cells in a pack. How many there actually are who knows. Another reason why I am favouring liquid yeasts more and more now, because they actually tell you straight out on the pack 100 billion viable cells (at packaging).

 

As for lagers, the reason I believe low temp pitching with more cells is better than warm temp pitching with less cells is because the cells don't have to multiply as much. Some esters are formed during this multiplication phase, and given most lagers are clean flavoured with minimal esters, it makes sense to limit their production as much as possible.

 

Petermur, that's basically the idea yeah. Note that I said simplest method, however it's far from the best method. In most cases it is a bloody huge over pitch (something like 5x) which can create problems of its own. I also tend to see it a bit like eating tonight's dinner off last night's dirty plates.

 

I think a better method if you don't go down the starter method described in this thread would be simply to scoop some of the yeast cake (say 1/4-1/3) up into a jar, clean out the FV, mix up the new batch and pitch the jar of slurry. Not sure how well it works with dry hopped beers though unless the hops have been contained in something. At least this way you won't be massively overpitching it. I have simply dumped the new batch onto the old cake once or twice and while the resultant beers were ok, they weren't anything noticeably better than pitching at proper rates. Now that I know more about pitching rates and how they affect the taste etc. I wouldn't do it again.

 

Cheers

 

Kelsey

[Dickster86]

Hi Dickster86.

Yeah because say i use a us-05' date=' according to the spec sheet it has 6 x 10^9 viable cells per gram, thats only 69 billion cells in an 11.5 gram pack. But if i look at yeastcalc it says for a 25L ale with OG of 1.050 i need 232 billion. So definitely a massive under pitch.[/quote']

Not true.

 

You're missing one very important symbol from the US-05 spec sheet on the viable cell count per gram, that being ">" at the beginning.

 

It should read "...Viable cells at packaging: > 6 x 10^9/g". That means greater than that number of yeast cells.

 

Jamil Zainasheff (co-author of the book "Yeast - The Practical Guide To Beer Fermentation") confirmed sometime back on a Brewing Network podcast that Clayton Cone (a Lallemand based yeast expert) said dry yeast has 20 billion cells/gram. He also says all of the tests he has done (i.e. cell counts after proper rehydration) show around 20 billion cells/gram. He offers the explanation that the yeast makers probably hedge their bets to account for poor storage and poor pitching technique (i.e. sprinkling on wort without rehydration) when giving the value of 6 billion cells/gram.

 

What you have in that single sachet of US-05 yeast is something a lot closer to 230 billion yeast cells, not 69 billion.

 

In the case of your brew, I'd be more inclined to scale back your volume from 25 litres to 21-23 litres @ the same 1.050 OG as you are certainly on the limits for a successful fermentation if using a single sachet of dry yeast in that configuration. That, or you can of course attempt to increase your starting volume of yeast cells through making a starter.

 

On a personal note I am still not convinced about what volume of yeast cells are actually required to adequately ferment out brews successfully, but do agree it is better to overpitch rather than underpitch.

 

Cheers,

 

Lusty.

 

That damned greater than symbol. You are quite right. I didn't read properly.

 

I imagine you are correct regarding the hedging bets aspect, at least i hope so anyway, would seem like a normal corporate ass covering technique, bit annoying though when you are trying to calculate a correct number.

 

Thanks for the info though Lusty, much appreciated. I always rehydrate these days, and normally add a bit of wort to the rehydrating mixture too, but that said the debate seems out on that too, hence why i'd like to start doing proper starters.

[Dickster86]

Yeah because say i use a us-05' date=' according to the spec sheet it has 6 x 10^9 viable cells per gram, thats only 69 billion cells in an 11.5 gram pack. But if i look at yeastcalc it says for a 25L ale with OG of 1.050 i need 232 billion. So definitely a massive under pitch.

 

Regarding lagers that totally makes sense to me. I like the idea of pitching at ferment temp, not pitching then cooling. That early stress stage cant do any favours to off flavours[/quote']

 

Yes, Lusty is right there about it being a minimum of 69 billion cells in a pack. How many there actually are who knows. Another reason why I am favouring liquid yeasts more and more now, because they actually tell you straight out on the pack 100 billion viable cells (at packaging).

 

As for lagers, the reason I believe low temp pitching with more cells is better than warm temp pitching with less cells is because the cells don't have to multiply as much. Some esters are formed during this multiplication phase, and given most lagers are clean flavoured with minimal esters, it makes sense to limit their production as much as possible.

 

Petermur, that's basically the idea yeah. Note that I said simplest method, however it's far from the best method. In most cases it is a bloody huge over pitch (something like 5x) which can create problems of its own. I also tend to see it a bit like eating tonight's dinner off last night's dirty plates.

 

I think a better method if you don't go down the starter method described in this thread would be simply to scoop some of the yeast cake (say 1/4-1/3) up into a jar, clean out the FV, mix up the new batch and pitch the jar of slurry. Not sure how well it works with dry hopped beers though unless the hops have been contained in something. At least this way you won't be massively overpitching it. I have simply dumped the new batch onto the old cake once or twice and while the resultant beers were ok, they weren't anything noticeably better than pitching at proper rates. Now that I know more about pitching rates and how they affect the taste etc. I wouldn't do it again.

 

Cheers

 

Kelsey

 

Yeah i almost did the pouring over the yeast cake method for the dark ipa (i still dont have a clue how to classify that beer, its nice though) i made recently, but decided against it and am glad i did. It was a two-can job with extra liquid and dry malt, and using both packs of kit yeast, rehydrated it went nuts almost straight away. Plus a lot of the feed back i got off this forum indicated it wasn't worth it for the small saving in time and money

[Otto Von Blotto]

It looks like I'm at the end of the line for the packet of US-05 that I had been re-using since about this time last year. The last two batches of APA I've fermented with it have both displayed strange aromas, like banana, and a weird phenolic type flavour. In both cases these problems are going away in time, but I suspect the yeast is the culprit due to it being re used numerous times and drifting away from its original state.

 

I've noticed with the latest batch that as the yeast drops out more in the keg, the flavour seems to be improving. There are no bottles in this batch. The previous one had bottles which exhibited this crap early on but improved in a few weeks. The kegged portion wasn't too bad on that batch. The batches before these last two didn't display these issues, and nothing has changed other than the hops used. Since I haven't got any need to visit CB just yet, I'll just grab another pack of US-05 and keep it going until I do go down there and pick up some 1272.

 

In contrast, the Urquell lager yeast which I've been re-using for the last 18 months isn't showing any signs yet of throwing strange off flavours like that. Maybe the liquid strains are more suited to it than the dry strains, or maybe it's just the strain itself. I haven't had the 1469 long enough to know its limit yet.

 

So, it looks like about 7 or 8 is the max I'd go to on re-uses of US-05 in future. That's still better than buying a fresh pack for every brew done with it though.

 

Cheers

 

Kelsey

 

[porschemad911]

Interesting, I wonder if that is the same flavour that Christina sometimes gets with US-05? Your description sounds similar to what she describes.

 

I guess it could have been a few things:

• Weak yeast - were those 2 batches slower to show signs of fermentation than normal? If so, it could have been an infection taking hold.
  
• Infected starter - were those 2 batches pitched with yeast that originally came from the same starter? If so, that starter could have been infected.
  
• Mutation over time - as you suspect
  

[BlackSands]

Interesting' date=' I wonder if that is the same flavour that Christina sometimes gets with US-05? Your description sounds similar to what she describes.[/quote']I've had the same thing several times too, but oddly for me it seemed to develop in the bottle as I was pretty sure it was tasting 'clean' at bottling time.

[Otto Von Blotto]

Interesting' date=' I wonder if that is the same flavour that Christina sometimes gets with US-05? Your description sounds similar to what she describes.

 

I guess it could have been a few things:

[list']

[*] Weak yeast - were those 2 batches slower to show signs of fermentation than normal? If so, it could have been an infection taking hold.

[*] Infected starter - were those 2 batches pitched with yeast that originally came from the same starter? If so, that starter could have been infected.

[*] Mutation over time - as you suspect

It could well be, and I agree it does sound similar to what Christina and Blacksands and a couple of others have described too.

 

As for the yeast itself, the two batches in question had pretty quick lag times, probably around 10-12 hours at a guess. The second one which is currently pouring reached FG in 4 days, so I think the yeast was fine in that regard.

 

Two different starters were used, as the first batch to show this was done about 2-3 months ago. The starter for the second one was built up from yeast harvested from the previous one, as per my normal procedure. Also, the same flask was used to build a 1469 starter for my latest ESB; this is also on tap currently and not displaying any of these flavours.

 

It should be noted that wheat malt has been mentioned as a possible cause for these flavours as well, and none of this was used in the brews. I haven't used it since my first few batches of AG actually.

 

I suspect it's most likely genetic drift/mutation of the yeast over time and re-use. When it comes time to ferment my next APA, I'll grab a new pack and start all over again and also take note of whether this flavour shows up in that batch too.

 

Cheers

 

Kelsey

[ChristinaS1]

Yes, it does sound similar to what I get sometimes. I see that White Labs recommend limiting repitches to 6-10 generations.

 

Just reading this on the Wyeast website:

 

"Strong sulfur or phenolic aromas indicate possible problems with either sanitation or stress."

 

https://www.wyeastlab.com/com-yeast-harvest.cfm

 

I am not sure I am reading that right? They seems to be saying that phenolic flavours can a be a sign of stress too, not just sanitation issues? That is the first I've heard of that. Here I was thinking that my yeast numbers were somehow a problem, that is insufficient, allowing wild yeast to gain a foothold, but maybe the issue is some kind of stress?

 

But you also mentioned wheat Kelsey. Come to think of it I use 300gm of wheat DME in a lot of my brews, to help with head formation. When I have time I will review my brew log to see if my brews with phenolic flavours where made with wheat. Maybe US-05, like some Belgian yeast, has a tendency to convert ferrulic acid, in wheat malt, into clove-like 4-vinyl guaiacol? If and when I use US-05 again, maybe I will hold the wheat DME and see what happens?

 

Cheers!

 

Christina.

[Otto Von Blotto]

That sounds about the max for this yeast, if that's what is causing these flavours. Everything in my processes is exactly the same as it always is, the only variable really is the yeast and how many times it's been re-used.

 

Yeast stress is known to throw shitty flavours, so that doesn't altogether surprise me. That's why I avoid under pitching by heaps, because it does stress the yeast. I don't think my yeast were stressed in these cases though.

 

It's also something that conditions out of the beer in time, in these two batches at least. It doesn't hang around or get worse, it just disappears. Maybe it's just because the beer is green, but it wasn't noticeable on previous APA batches up until this one and the one before it. I'll go grab another packet of US-05 and use it until I visit CB next, when I'll pick up some 1272.

 

I'll taste the APA again tomorrow night and see if it's improved more than it already had done. I had noticed the flavour had begun to dissipate even over 3 days sitting in the keg in the fridge.

 

If you want head formation/retention etc. without using wheat malt, you could try a 200-250g steep of Carapils. It does pretty much the same thing as wheat malt - which is the main reason I didn't buy any more wheat malt after using up the original 1kg I had. Flavour might be a little different but I enjoy my beers without wheat in them. Late hops and dry hops can apparently aid in head retention as well.

 

Cheers

 

Kelsey

 

 

 

 

[joolbag]

I’m posting to report my first successful starter build! Thanks so much Otto for reviving this post and giving some detailed instructions.

 

I’m paying it forward, in the hope that someone else can get some good information from my experience and apply it to their own home brewery.

 

You may recall that I fermented a Munich Helles with Mangrove Jack’s M76 Bavarian Lager. For this brew I pitched two 10g dry packets of yeast and collected yeast slurry. Slurry was collected about 6 weeks ago.

 

I used MrMalty to estimate how many cells were in my slurry (~200bn). Then used YeastCalc and Brewer’s Friend to work out how many billion cells were required for my next brew, which is a TC pilsner kit with Briess pilsner extract and a short boil of Saaz hops (411bn).

 

I built the starter to 511bn cells with the intention of harvesting 100bn from the starter. Worked out well, but I needed one helluva starter using the shaking method for aeration. 4L of 1.040 wort for a lager stater. I used a 10L water container and shook the hell out of it over the weekend. It took about 36 hours to fully ferment and the krausen to drop. I agitated it, poured out 100bn cells (one fifth of the liquid) into a storage jar into the fridge.

 

As per Otto’s method, I crash chilled it so I could minimise the amount of spent “beer” that would end up in my brew when pitching. Pitched the 411bn cells last night at 10.40pm.

 

Lessons learnt:

• Shaking needs a much larger starter than a stirplate according to the calculators. This was a good foray into yeast management and is easy and cheap to get “started” – hahah pardon the pun. Perhaps down the road I will build or invest in a stirplate.

• My collected slurry had some trub and crap in it. I’ll probably use it one more time for a Dortmunder Export lager, then let it go. In the future I will start with dry yeast packet(s) or liquid yeast because I want to see pure, clean yeast, rather than carry stuff across from a previous brew.

 

So get into it! It is more effort than rehydrating a packet or two, but not much. Time will tell if it will be a rewarding return on investment; my logic is that it certainly can’t hurt the brew to pitch closer to the right amount of yeast.

 

Jools

 

[ChristinaS1]

But you also mentioned wheat Kelsey. Come to think of it I use 300gm of wheat DME in a lot of my brews' date=' to help with head formation. When I have time I will review my brew log to see if my brews with phenolic flavours where made with wheat. Maybe US-05, like some Belgian yeast, has a tendency to convert ferrulic acid, in wheat malt, into clove-like 4-vinyl guaiacol? If and when I use US-05 again, maybe I will hold the wheat DME and see what happens?

 

Cheers!

 

Christina.[/quote']

 

Just went through my brew log found that I have used wheat in about one third of my batches. One in four batches made with wheat had phenolic flavours, but it hardly ever occurred in batches made without wheat (just twice, and those batches both had issues). Hmm, maybe this is more than a coincidence? That is enough for me to reconsider using wheat.

 

FWIW, I used US-05 together with wheat four times. Two were phenolic and two were not. While that is a small sample size, it is double the rate of the other yeasts combined.

 

It would be interesting to take slurry from a phenolic wheat brews and repitch it into a brew made without wheat. If the phenolic flavour was cause by wheat, the second brew would taste clean; if it also tasted phenolic, then it would be due to contamination. But I am not going to risk a batch to that experiment, partly because I am going to stop using wheat.

 

Cheers.

 

Christina.

[Otto Von Blotto]

No problems Joolbag, glad to hear everything went well. Did you also use the cold pitching technique into the main batch last night?

 

A stir plate does make things easier it must be said, for one thing you don't need a hugeass container to make the starters in. They work best with Erlenmeyer flasks; I have a 2L, 3L and 5L. These can be boiled on the stove, so I simply mix up my wort in the flask, drop the stir bar into it and boil the lot on the stove. Once cooled the yeast is pitched and it's put on the stir plate for 24-36 hours.

 

I have a heated (or more accurately, heat-able) stir plate, which is excellent through the cooler months for doing ale starters, although I use the heating for lagers too so they don't take forever. I use the stir plate for things other than yeast starters too, so they can be a useful piece of equipment to have anyway.

 

Cheers

 

Kelsey

[joolbag]

Hey Otto, I did cold pitch. Thanks for that thread too! I friggin' love this forum and the brewing community we have here. You helpful chaps n gals (you know who you are) have been great at stoking and improving my hobby and recent obsession.

 

Now should I/would I create a starter for the 11.5g of K-97 yeast that I have planned for my next brew which is a Kolsch... only have one packet, which would be technically an under pitch... look what you guys have done! You've created a monster!

[Otto Von Blotto]

Big fan of the cold pitching after using it on a number of batches since I posted that thread. It doesn't seem to have done much with the 2001 yeast I use, but the two ale strains kick off really quickly with it.

 

I'll be dumping the jar of US-05 next week and cleaning that jar out to be ready for next time I use that yeast. I'll get another packet and use it until I go to Craftbrewer next, when I'll pick up some 1272 to use instead.

 

Next starter will be for some 1469 for my red ale which is due in the FV next. Probably make it up on Monday. Hopefully this one doesn't escape the flask and make a mess of everything like the last one did

 

Cheers

 

Kelsey

[Beerlust]

Next starter will be for some 1469 for my red ale which is due in the FV next. Probably make it up on Monday. Hopefully this one doesn't escape the flask and make a mess of everything like the last one did

From what I've read & seen about 1469' date=' there is no such thing as "hope". [img']lol[/img]

 

 

Cheers,

 

Lusty.