Dry Vs Liquid

[Nick JD]

I add some water to my dry yeasts. :blink:

 

[hazard]

Probably that some yeasts are only available as a liquid although I understand liquid to be considered better for reharvesting too. I use 05 over 1056 but that's as much due to the fact that beers in which I use 05 rely on a clean yeast - I'm not looking for stone fruit esters etc and 05 does the job well.

So do you harvest yeast from US-05? I have used WY1056, but recently used US05 for an amber ale because I didn't have time to make a starter. As usual, I threw out yeast cake from the primary, and collected all the yeast from the secondary (its now in a jar in the fridge). I expect that most of the yeast I have collected is "new" yeast that grew during fermentation, is there any reason why this yeast would be different if the original medium was liquid rather than dry? I can't see why it would be, but I have seen other posts that make the comment that its not ideal to harvest from dry yeast - just wondering if there is any real reason.

 

[katzke]

With all the malt and hop choices to brew with I have decided to limit my yeast choices. Changing the fermentation temperature can get a big difference in flavor. I am also overly sensitive to yeast esters so have settled on US-05 and S-04 dry yeast. Belgian yeast makes beer taste like bubble gum to me. The wheat yeasts have too much clove or banana for me. I brewed an Irish Red with S-04 and it was as good as the commercial beer I tasted to compare it to. With all the malt and hop choices I have decided to limit my yeast choices to simplify my brewing.

Liquid yeast also requires a starter for most brews. Dry yeast is a bit more forgiving. If the packet is not big enough the cost is low enough for me to just pitch a second pack. So far I have not had any problems with pitching rates. I think I did have that problem when I started brewing and was using liquid yeast.

A note, I am a few hours from the yeast factory that makes the smack packs.

So it is dry yeast for me. Why? Because of cost, ease of use (no starters or mucking about), and most important I am happy with the results.

 

[boobiedazzler]

I dont get this either. If the dry yeast has replicated itself, then surely the yeast health is then optimum, regardless of the condition of the original pack.

Concerning yeast out of secondary, I read just last night in JP's textbook that the secondary yeast cells are less flocculant, therefore future beers will be slower to clarify. But again, I dont see how this is relevant if you make up a small starter from the secondary harvest to create new, vibrant cells.

 

[katzke]

I expect that most of the yeast I have collected is "new" yeast that grew during fermentation, is there any reason why this yeast would be different if the original medium was liquid rather than dry?

Any yeast can be different in later generations.

I am not a yeast harvester.

 

[Pennywise]

I try and stick to liquid because it's alot cheaper, I do always have a few pack of dry though for emergencies. I get 20 brews from a pack of wyeast. I don't like harvesting from trub so I stick with liquid and spilt the wyeast pack

 

[boobiedazzler]

To Katzke's comment - the fermentis dry yeasts are 11 grams, which is double that of kit yeast sachets. If one fermentis pack is considered not enough by half, then how do the kits packets manage to get the job done, being half as much in weight again?

Although I have made over 30 batches, mostly partials before the recent move to AG, I dont really have the expertise to tell what the negative impact has been with alleged underpitching which by all accounts I have been doing in the past. Using liquid yeasts several generations down the line from an original liquid strain, not following all the stringent washing techniques (but ensuring good sanitation of course) I am yet to observe any problems. To be honest though, I have never brewed the same beer twice, nor done any side by side comparisions - something I hope to do in the near future with split batches.

As far as following ALL the rules with yeast management, how do people rate it's importance to a new AG brewer - personally Im focusing more on my mash efficiencies for the time being, because... well, because I think its more important.

 

[boobiedazzler]

Comments flying thick and fast LOL, cant keep up with relevant responses.

If yeast is mutating between generations, does this mean that one can create their own blended strains, theortically, or will ther be a dominance of one or the other ? As an example, I pitched a whitelabs wheat yeast a few weeks ago, after 40 hours there was zero activity so I pitched a packet of S04, all I had to hand, which started the activity quickly. The resulting beer is not very good, its clearly a wheat-based beer with not much wheat yeast flavour, and the reserved trub clumped heavily, which is to be expected of an English Ale yeast, and not a wheat.

My conclusion is that the S04 dominated during the reproduction cycle.

 

[katzke]

As far as following ALL the rules with yeast management, how do people rate it's importance to a new AG brewer - personally Im focusing more on my mash efficiencies for the time being, because... well, because I think its more important.

I think it is all important. You have brewing experience so hopefully you have found and fixed some mistakes in those first 30 brews. If not then you lead a charmed life.

Other then gross sanitation issues yeast management, mostly proper fermentation temperature, is the single most important part of brewing. Least that is my opinion. There is a lot to yeast health and management. Some even crosses over to helping the mash process.

 

[katzke]

Comments flying thick and fast LOL, cant keep up with relevant responses.

If yeast is mutating between generations, does this mean that one can create their own blended strains, theortically, or will ther be a dominance of one or the other ?

My conclusion is that the S04 dominated during the reproduction cycle.

You have to remember that yeast reproduce mostly by cloning. There is a sexual aspect and I can not say what percent of reproduction is from each part.

Mainly yeast are living and all living things mutate or evolve. That is how we were able to create better crops with out fancy science labs. The farmer noticed a plant or animal did better and selected it for future planting or breading.

If you brewed the same beer enough with multiple separate yeast cultures you may notice one yeast produces better beer and toss the other less desirable yeast. That is how we ended up with the zillion yeast stains we have now.

As home brewers we have several problems. One is batch size and the limits it imposes on repeatable results. The other is we brew so many different beers we rarely get the chance to repeat a brew. Last is we have no control over our raw materials. All of this and more makes it very hard to know just what makes any difference in our results. That is why I have simplified my life and limited my yeast selection.

 

[Nick JD]

Here's a question: how long does a yeast cell live for?

I've often wondered if someone is stepping up a starter from a slant and they are aiming for a billion cells, but they start with only a million ... I'm no mathemagenious, but to make a billion from a million through "budding" (exponential growth (simplifying it a little)) then the yeast that's actually pitched in the fermenter is ten generations older than the original.

How many generations does the 100 billion cells go through to multiply to a fermenter-load of yeast?

What I'm getting at is, are we only considering a "generation" as "each time we pitch"? And disregarding the actual amount of budding that's taken place?

 

[Pennywise]

Interesting point, I've not noticed any changes in re-using 4 times

 

[Bribie G]

I'm currently brewing like a madman for the BABBs comp, as I moved house a few weeks ago and just got back into brewing after a month off so, to keep myself in quaffables I'm doing a series of kits n bits until my mashed brews stock gets back to normal. I found a pack of US-05 in the freezer and resurrected that and used it in a Coopers lager with BE2 and steeped crystal and some US late hops - I'll be doing three of the same brew as a keg filler over the next month and intend to just repitch the US-05 each time, so it will be interesting to see how they turn out, if there is any difference that can be attributed to the yeast.

 

[Nick JD]

Interesting point, I've not noticed any changes in re-using 4 times

That's kinda what I'm getting at. If mutational changes are the problem here then here's two scenarios:

1.) A whole pack of liquid yeast is pitched into a 25L brew. It breeds up and ferments out. The trub is kept for the next brew.

...what is the average generational gap between the pitch yeast and the trub yeast?

2.) A pack of yeast is used to make slants and the rest pitched. The trub from the pitch is thrown out. Each time a new brew is done a starter is made up from a very small amount of yeast.

...what is the average generational gap between the few yeast in the starter and the eventual trub?

Will 1. be fewer generations away from Wyeast's original after being reused five times than 2. being used once?

 

[Pennywise]

I've never had anything to do with slants, but I spose the difference between the two scenarios would depend on how many time you need to step the starter up to get tha same amount of trub?

 

[boobiedazzler]

Good point, although I wonder what sequence you are using - 1,2,4,8,16,32 etc. I have been doing my head in for the last 20 minutes trying to prove to myself why that doesnt feel like the right way to look at it. Maybe its a brewer's practical reference when speaking of generations, not a microbiologist's one.

 

[Nick JD]

I've never had anything to do with slants, but I spose the difference between the two scenarios would depend on how many time you need to step the starter up to get tha same amount of trub?

So if you start with a million cells and you need 100 billion that's like 18 generations - I have no idea how many cells in a slant though.

If stepping up small populations is cool for yeast use ... why the bad news about reusing trub ten times?

 

[Pennywise]

For me, the only reason I prefer not to use the trub is I believe there'll be more of an infection risk because there's a bit more handling. I guess on the plus side for trub, there's usually hop debri left which could act as a preserver if you were to keep it for an amount of time

 

[manticle]

So do you harvest yeast from US-05? I have used WY1056, but recently used US05 for an amber ale because I didn't have time to make a starter. As usual, I threw out yeast cake from the primary, and collected all the yeast from the secondary (its now in a jar in the fridge). I expect that most of the yeast I have collected is "new" yeast that grew during fermentation, is there any reason why this yeast would be different if the original medium was liquid rather than dry? I can't see why it would be, but I have seen other posts that make the comment that its not ideal to harvest from dry yeast - just wondering if there is any real reason.

Generally not. I did save a bit of 05 slurry in a few longnecks a while back but opening and smelling proved that to be a waste of time. Stinky stuff that I wouldn't use. Screwtop has mentioned a few times about bacteria multiplying inside dried yeast (there is a small bacteria content in the dried stuff when fresh which multiplies as the yeast multiplies) and it's cheap enough not to worry too much.

I reharvest/split most of my liquids though.

I'm sure there's info out there more specific than my fairly unspecific reasoning above.

 

[boss brew]

I have pitched onto an US05 cake with excellent results, and have brew buddies that have done the same. Never tried more than 1 though...it's just too cheap to buy a pack or 2!

Dave