# Why Don't All Strains Dry?



## RobB (25/4/13)

I have had a look through Chris White's "Yeast" and scoured this new fangled interweb thingy, but I can't find why some strains of yeast are able to be dried while others can't.

Is their a single governing characteristic which indicates that a yeast is able to survive the drying process? I've got this image in my mind of a bloke in a lab coat, looking into a microscope going "phwoar, nice lipids....."

I think it's pretty exciting that we have had a few new dry yeasts introduced recently and I was wondering which other strains might be in line for this process and which strains will simply never make it.

Any mycologists out there?


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## hoppy2B (25/4/13)

I don't think I have ever seen anything but a dry wine yeast. 
I'd be surprised if all yeast couldn't be dried. Some companies seem to just make liquid yeast and they may have their strains covered by patent.


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## Screwtop (25/4/13)

Like all questions commercial...................................... if in doubt, tick cost!

Screwy


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## manticle (25/4/13)

hoppy2B said:


> I don't think I have ever seen anything but a dry wine yeast.
> I'd be surprised if all yeast couldn't be dried. Some companies seem to just make liquid yeast and they may have their strains covered by patent.


What are you talking about?


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## black_labb (25/4/13)

manticle said:


> What are you talking about?


I think he's talking about the strains that they pinched from a brewery and then patented... but that didn't happen


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## slash22000 (25/4/13)

To sell more expensive liquid yeast, I would imagine.

I don't want to come off as a conspiracy theorist or anything but aside from the variety liquid yeast has every disadvantage. It dies about an hour out of the factory door, you need to **** around with making starters, you can't post it anywhere without an FBI escort in a liquid nitrogen container, it costs twice as much for half the yeast ...

... Okay so I'm exaggerating (slightly) but seriously, I'd be interested to know the answer to this question.


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## bum (26/4/13)

Demand.


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## Womball (26/4/13)

The thing I remember about this after listening to hours of podcasts on brewing is that some yeasts are better suited to the drying/rehydration process than others......They are able to survive. I believe the process for manufacturing dried yeast has got much better in the past few years and it's likely the more dried yeast strains will become available in time.


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## jc64 (26/4/13)

This is a great question, as far as I know everyone who promotes the use of liquid yeast cites the variety available as the number one reason to purchase them. Then they use WLP001 for most beers anyway.

I do like trying out other types of yeast, at present I have a oatmeal stout with s-04 fermenting alongside a Irish Red with WLP028. So I do use liquid yeasts but would use dry every time if it was the same strain.


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## Logman (26/4/13)

I read in a Coopers thread the other day that Coopers have not been able to successfully develop their yeast as a dry yeast and that's why you have to make a starter from the bottles. The thread made it sound as though they gave it a go but weren't able to.

That info could be wrong though I guess...


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## Ducatiboy stu (26/4/13)

Longman you are correct. I spoke to Dr Tim about it and it won't dry successfully . They are keen to use their commerciall yeast for kits but it just won't work. They had to find a dry yeast that was similar for their kits. That's why they promote making starters from bottles. Bottle and keg yeast are the same.


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## Yob (26/4/13)

And they sell more bottles


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## hoppy2B (26/4/13)

manticle said:


> What are you talking about?


Once upon a time there was no such thing as dried yeast. In the wine yeast category I am unable to find or have never seen a liquid wine yeast advertised for sale as far as I can remember. 
Yeast drying tech is improving all the time and I would be surprised if there isn't a company out there with the tech to dry Coopers yeast.


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## Bribie G (26/4/13)

I don't know if Coopers produce their own kit yeast, if not then Mauri at Toowoomba are the only yeast drying mob in Australia AFAIK so I guess it's a very technical and specialised operation. Mauri do the bread yeasts by the tanker load and HB is a sideline.

If most strains could be dried then you can bet that Wyeast or some other US company would be cranking them out in bulk so you don't have to do the smack and starter routine. From US forums it seems that, as here and the UK, they still rely on good old Danstar etc.

Edit: I used Edme dried yeast in the late 60s onwards, so I don't know how far back you want to go.


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## bum (26/4/13)

It is an expensive process and the break-even point is at ridiculous volumes (in terms of production and sales - this process isn't "small batch" friendly as I hear it). There won't ever be a direct mapping between liquid and dry yeast varieties (unless the arse falls right out of the liquid yeast market, I guess).


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## Logman (26/4/13)

bum said:


> It is an expensive process and the break-even point is at ridiculous volumes (in terms of production and sales - this process isn't "small batch" friendly as I hear it). There won't ever be a direct mapping between liquid and dry yeast varieties (unless the arse falls right out of the liquid yeast market, I guess).


I guess this begs the question as to how Coopers tried to produce their yeast as a dry strain i.e. did they try to get someone to do it or did they make some sort of attempt of their own. It makes sense that they could have justified decent expenditure on trying given that it would have gone in all of their kits, plus the fact that it was popular amongst home brewers.


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## Ducatiboy stu (26/4/13)

Coopers use Mauri for their kit yeast.


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## Yob (26/4/13)

They have a yeast lab on site and a resident yeast guy.. Paul used to have to run away and ask him questions when I drilled him about Coopers yeast questions... So presumably on site


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## growler (26/4/13)

My 2c

I think Coopers uses 2 different yeast types for their kits. 

Back in my K&K days I noticed the more expensive kits had INT stamped with the date on the outside of the yeast sachet and the texture was a mixture of large and small particles of different colours.... relatively speaking of course!

The standard kits all had the same size particles that were the same colour. 

.... but....I know bugga all really. 

G.


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## DUANNE (26/4/13)

slash22000 said:


> To sell more expensive liquid yeast, I would imagine.
> 
> I don't want to come off as a conspiracy theorist or anything but aside from the variety liquid yeast has every disadvantage. It dies about an hour out of the factory door, you need to **** around with making starters, you can't post it anywhere without an FBI escort in a liquid nitrogen container, it costs twice as much for half the yeast ...
> 
> ... Okay so I'm exaggerating (slightly) but seriously, I'd be interested to know the answer to this question.


so danstar and fermentis are only interested in selling more liquid yeast? im sure that if it was possible these guys would have a lot more strains on offer and if the saison and west coast ale yeast releases are anything to go by then they are working on it.


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## Mardoo (26/4/13)

hoppy2B said:


> n the wine yeast category I am unable to find or have never seen a liquid wine yeast advertised for sale as far as I can remember.


Now White Labs and Wyeast both sell liquid wine yeasts.:

http://www.whitelabs.com/wine
http://www.wyeastlab.com/hw_products.cfm


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## hoppy2B (26/4/13)

Mardoo said:


> Now White Labs and Wyeast both sell liquid wine yeasts.:
> 
> http://www.whitelabs.com/wine
> http://www.wyeastlab.com/hw_products.cfm


Cool, thanks for that. I have only ever notice the dry stuff.


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## Yob (26/4/13)

http://www.winemakermag.com/guide/yeast

Plenty about...


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## super_simian (26/4/13)

Ducatiboy stu said:


> Coopers use Mauri for their kit yeast.


I noticed in a previous post you mentioned having had a word with Dr Tim; did he give you that information? I know they use Mauri to *manufacture* their dried yeast, however Coopers have said on record that their dried yeast is a proprietary strain. Which would make it different to 514 ale yeast. I'm not trying to pick a fight here, just wondering if you have it from the horses mouth.



growler said:


> My 2c
> 
> I think Coopers uses 2 different yeast types for their kits.
> 
> ...




You are somewhat right; there are comprehensive guides for what yeast comes with what Coopers kit (here and on other sites), but they use more than 2 all up. And in at least one instance the supplied yeast is a blend, which may explain the difference in appearance.


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## Yob (26/4/13)

this thread on the Coopers site outlines what the blends are for those that are interested 

http://www.coopers.com.au/the-brewers-guild/talk-brewing?g=posts&t=1803


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## Ducatiboy stu (26/4/13)

It is a propriety strain, but not the strain used in their bottles. 

I had the pleasure of talking to Dr Tim for over an hour. He had much to say and was very open and passionate about beer. Even down to priming rates etc. They would have like to use the bottled yeast as a dried yeast but they could not get it to dry successfully . Hence they advocate the use of recoultering bottled yeast.


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## peas_and_corn (26/4/13)

It's possible the Coopers yeast does not utilise glycogen stores very well.


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## super_simian (26/4/13)

Ducatiboy stu said:


> It is a propriety strain, but not the strain used in their bottles.
> 
> I had the pleasure of talking to Dr Tim for over an hour. He had much to say and was very open and passionate about beer. Even down to priming rates etc. They would have like to use the bottled yeast as a dried yeast but they could not get it to dry successfully . Hence they advocate the use of recoultering bottled yeast.


Did he have much else to say on their kit yeast? Because I've heard all kinds of things, including that it's "bread yeast" and of course "it's 514," and TBH I've used it for a few AG brews recently, with no complaints. Actually seems better to my palate than 04 or Notts. Knowing a bit more of its provenance would be good.


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## RobB (27/4/13)

Plenty of good replies, but I think the answer is more likely to do with the yeast rather than with the economics.



bum said:


> It is an expensive process and the break-even point is at ridiculous volumes (in terms of production and sales - this process isn't "small batch" friendly as I hear it). There won't ever be a direct mapping between liquid and dry yeast varieties (unless the arse falls right out of the liquid yeast market, I guess).


Adding the extra step of dehydration, plus whatever is required to get the yeast ready for this harsh treatment, will certainly add cost. However, I can buy 220 billion cells in dry form for $4.50 and only 100 billion cells in liquid form for $9.80 (Craftbrewer, Nottingham vs Wyeast). Even in the US, with the freight cost all but removed from the liquid yeast, it's $4.00 vs $6.25 (Northern Brewer).

Cell for cell, dried yeast is cheaper to the end user, be they amateur or professional. However, I see your point about volume, and if a company wants to offer dozens of strains then perhaps liquid is their only option.



Womball said:


> The thing I remember about this after listening to hours of podcasts on brewing is that some yeasts are better suited to the drying/rehydration process than others......They are able to survive. I believe the process for manufacturing dried yeast has got much better in the past few years and it's likely the more dried yeast strains will become available in time.


I think this might be closer to the mark. Consider WB-06 - a good yeast with both fans and detractors, but how much greater would the demand be if they had been able to dry 3638 or 3068? I don't think WB-06 was chosen by Safbrew over 3068, I think it chose itself because it survived drying when 3068 wouldn't.



peas_and_corn said:


> It's possible the Coopers yeast does not utilise glycogen stores very well.


This is the kind of detail I was hoping to get into. Is a cell's ability to withstand dehydration governed by its structure, its metabolism, or some other factor?


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## Feldon (27/4/13)

Malty Cultural said:


> Is a cell's ability to withstand dehydration governed by its structure, its metabolism, or some other factor?


 or cell wall thickness


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## manticle (27/4/13)

Without getting too super scientific about it, consider the impact of dehydration on so many other foodstuffs and the fairly intense flavour impacts.

Mashed potato/deb, milk/milk powder, chicken soup, beer kits are but a few to consider. Never met a 'just add water 'idea that matched something that retained its water in the first place and the reason is probably because sucking the water out of something is a very harsh process. Some things don't cope and if they do cope, they are not necessarily the same afterwards.

None of this is meant to suggest I am not interested in the exact scientific process that occurs on a cellular level because I am - very.

As an aside - I'm not sure why people think using liquid yeast is difficult. A smack pack gets smacked and left for a while till it expands and then you can either add it straight to the wort if the gravity is low enough or make a starter. You can split and step up to save money but that is not a requirement.

A dry yeast pack can be added straight to wort (no need to smack) or rehydrated and if you read the proper instructions for rehydration, they are specific and require some small effort (bit like making a starter). If your gravity is high, you may need two packs, negating the supposed cost saving over liquid.

The extreme of open and sprinkle for dry versus the extreme of step and start on a stirplate for liquid does not represent the only way to use either.

You can **** around with dry and you can open and pour with liquid.


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## Nick JD (27/4/13)

manticle said:


> I'm not sure why people think using liquid yeast is difficult.


I am. You have to make a starter with it - otherwise you have no control over your pitch rates.


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## bradsbrew (27/4/13)

Nick JD said:


> I am. You have to make a starter with it - otherwise you have no control over your pitch rates.


Rubbish. I have never made a starter with a liquid yeast.

Edit. I must clarify that I only have used wyeast smack packs and have not used the white labs test tube vials.


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## GuyQLD (27/4/13)

bradsbrew said:


> Rubbish. I have never made a starter with a liquid yeast.


I haven't either. But I tend to only brew styles where I want to use a liquid yeast based on when Ross gets a new supply. In that regard I'm somewhat treating them as "seasonal" (the "season" being when Ross gets new stock). Past a certain age, I look to a different beer. 

I consider this more a limitation of my own fear of messing around with starters than a limitation of liquid yeasts. 

The reality is however that the majority of the time a starter is probably a good idea.


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## slash22000 (27/4/13)

I've never used liquid yeast (no stir plate, yet), but I've noticed liquid yeasts on some sites with manufacturing dates like "June 2012" or something ... I tried plugging them into a yeast calculator and it tells me that they're virtually completely useless by that stage.

Are we at the whim of when retailers happen to get new stock? Is there a place in AU where we can get fresh yeast on demand? How do so many Aussie brewers use liquid yeast if it's so volatile?


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## bradsbrew (27/4/13)

I have used plenty of wyeast smack packs. In my opinion, if it swells it will work within the gravity range stated by the manufacturer. Have not been let down yet and I get the expected final gravity. I also no chill and get a great airation before pitching. When doing big beers I will use a yeast cake which I guess you could call a starter of sorts.

Cheers


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## Yob (27/4/13)

It would be good to have the option of the variety that you get with liquid as dry.. I really have to get my shit together and try a few more liquids


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## Nick JD (27/4/13)

bradsbrew said:


> Rubbish. I have never made a starter with a liquid yeast.


Then you're underpitching by miles unless it's under a couple of weeks old.


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## whatwhat (27/4/13)

wtf


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## manticle (27/4/13)

Nick JD said:


> I am. You have to make a starter with it - otherwise you have no control over your pitch rates.


Have to?

I use liquid yeast almost exclusively* and I make starters for some beers and not others. That's like saying you HAVE to rehydrate dried yeast.

You can make either format easy or difficult for any number of theoretical reasons.


*Nowadays - have used plenty of dried yeast straight out of the pack as well as rehydrated previously.


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## Bizier (28/4/13)

bradsbrew said:


> I have used plenty of wyeast smack packs. In my opinion, if it swells it will work within the gravity range stated by the manufacturer. Have not been let down yet and I get the expected final gravity. I also no chill and get a great airation before pitching. When doing big beers I will use a yeast cake which I guess you could call a starter of sorts.
> 
> Cheers


I don't mean to be overly rude, but that is average practice at best.


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## bradsbrew (28/4/13)

bradsbrew said:


> Rubbish. I have never made a starter with a liquid yeast.
> 
> Edit. I must clarify that I only have used wyeast smack packs and have not used the white labs test tube vials.





Nick JD said:


> Then you're underpitching by miles unless it's under a couple of weeks old.


OK, I understand and get what you are saying. What negative effects should I be getting by doing this? Are you speaking from practical or theoretical experience?



Bizier said:


> I don't mean to be overly rude, but that is average practice at best.


Yes, going by from what I have read it could be viewed as exactly that, as are other parts of my brewing process. I just see it as a step I dont need to perform to get good results. I have received good feedback and results at local, state and national level with my average practices.

If i am not feeling to lazy next time I might make a starter and see if I can pick a difference.

Cheers


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## Nick JD (28/4/13)

bradsbrew said:


> OK, I understand and get what you are saying. What negative effects should I be getting by doing this? Are you speaking from practical or theoretical experience?


Practical. It's the very reason I gave up expecting a smackpack to be pitchable. The chronic areas I had issues with were hefes, wits and lagers - all of which IMO are very susceptable to pitch rates.

Let's use a German Pilsner as an example. 1.055 OG, 20L batch ... Mr Malty assumes a 1 month old pack has a 79% viability (this is a pack manufactured _this month). _The appropriate pitch is *4.9* smackpacks.

Wyeast lager packs can financially never be direct pitched.

The only smackpack I have ever been totally happy with direct pitching was a 3787 that was a couple of weeks old into a 14L batch of Dubbel. Mainly because it puffed up like a pufferfish, and that yeast is on steriods - but in virtually all other instances directly pitching smackpacks (even in ales) will be underpitching by half, or more. Still probably makes good beer, but.

Oh, and I direct pitched a Belgian Saison once, mainly because it was 35 degrees.


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## Bribie G (28/4/13)

Being a no chiller I keep a litre schott bottle of clear wort, cool it down and pour into a 4L lidded round 'bucket' from a cheap shop that I keep for the purpose, kept Starsanned in between uses, add the yeast from the swollen smack pack , shake to oxygenate, "crack" the lid seal slightly and gladdy the whole top. Never fails to fire up, then pitch next day when the cubes are cool. That way I'm assured of a healthy pitch rate right when I need it the next day.

I've kept liquid yeasts for a year and when swollen, often after only a couple of days, they fire up just fine.

I once accidentally froze a smack pack for three months, I'd inadvertently put it in the freezer in a container of hops. It fired up just fine as well.

Edit: when using slurry I half fill a litre schott bottle with liquid slurry, fill it to the top with deox sterile water, shake and come back later to collect the layer of yeast that sits on top of the trub.

That goes into ye faithful tub with the litre of wort and it usually fires up like I'm using a fresh smack pack.

Edit: Edit: some of the worst twangy beers I have tasted have been from crazy stir plate fanatics who start with a tiny yeast sample they've had hanging around for a year, then stir for days and days in the garage. Probably bred up a whole flock of wild yeasts and bacteria whilst doing so. That's why I prefer to use fresh smackpacks, let them run for three generations at the most, or use a good trusty dried yeast like US-05 if I run out. In fact US-05 is the only dried yeast I've used for years, apart from two sachets of Morgan's lager (Mauribrew).


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## peas_and_corn (28/4/13)

OK, something interesting from Brewing Yeast and Fermentation by Boulton and Quain-



> Trehalose is known to confer resistance to heat and desiccation in a diverse range of
> organisms such as insects, plants, yeast and higher fungi. In addition, it is associated
> with spore formation (Elbien 1974; Crowe et al., 1984; Neves & Francois, 1992; de
> Virgilio et al., 1994). Colaco et al., (1992) described the ability of trehalose to stabilise
> ...


It's made clear that this is speculative, the role of trehalose is not definitely confirmed, but is certainly believed to help in protecting the yeast cell during storage. Perhaps some yeasts have difficulty synthesising it?

Page 93, if you would like a pdf of the book, PM me.


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## RobB (28/4/13)

Thanks P&C. Dr Google was much more helpful once I added "trehalose" to my search parameters.

From here: http://www.bioaliment.ugal.ro/revista/2/Paper1pfit.pdf

_"More recent studies have established a stronger correlation between the trehalose content of yeast cells and their resistance to temperature extremes, dehydration and freezing-thawing cycles........_

_......The fact is already accepted that high trehalose levels are important for producing active dry yeast._"

Perhaps only strains with naturally high levels of trehalose are selected for dehydration?


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## bconnery (28/4/13)

There's been discussion around the place that mr malty overstates its pitching rates, thinking more on a commercial scale than a homebrew one.
As one who has nearly always used liquid yeast smacked and direct into the brew, with the exception of lagers, I can't defend it as best practice, but I can defend it as workable practice...

With regards to the original question, I've also read about the place that some strains simply don't dry well...


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## mje1980 (30/4/13)

I used to direct pitch, but occasionally, the yeast would just take too long. Now I make startes for pretty much everything. If its very fresh, and swollen like crazy, and I'm pitching into a 1.035 mild, I might direct pitch, but otherwise, a starter it is for me. 

Get the "yeast" book by JZ, very informative, and a great reference.


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