Why Don't All Strains Dry?

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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.
 
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
 
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.
 
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).
 
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
protein structure such that in the presence of this disaccharide many enzymes exhibit
startling resistance to heat and desiccation. Iwahashi et al. (1995) used whole cell
NMR analysis of yeast and concluded that trehalose protected cells from temperature
extremes by stabilising membrane structure. Further circumstantial evidence for a
role for trehalose distinct from that of simple storage carbohydrate is provided by the
fact that its synthesis requires metabolic energy, whereas no ATP is generated in its
dissimilation. Trehalose has been shown to be a most effective agent for preventing
damage to membranes by its ability to prevent phase transition events in lipid
bilayers. The mechanism of action appears to be via binding of the hydroxyl groups of
the sugar to the polar head groups of phospholipids in locations otherwise occupied
by water. For maximum effectiveness, trehalose requires to be present at both the
inner and outer surfaces of the membrane (Crowe et al., 1984)
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.
 
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?
 
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...
 
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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