yeast?

[barrelboy]

Hi all, there is probably already answers to questions ask, but I think their in all different threads so I've call this yeast, just for yeast questions. Just bottled a stout style brew, will 500 ml of extracted yeast be enough for my next brew? Also what detrimental affect does a yeast from one style, eg stout, have if you use on say a lager?
Cheers all BB

[warra48]

Not sure what you mean by "extracted yeast". Which yeast did you use?
However, if you mean you have 500 ml of slurry from your last brew, then, yes, it is enough to pitch into your next brew.

The general wisdom is that if you wish to use the harvested yeast slurry from one brew to use in the next, you go from the lighter to the darker beer.
And, of course, you need to ensure the yeast is appropriate for the style you wish to pitch it into.

I'd say that pitching the harvested yeast from a Stout into a Lager is to set yourself up for a less than satisfactory outcome. It will, no doubt, ferment it, but it's not ideal. One's an Ale, the other is a Lager. Even the fermentation temperatures and characteristics are quite different.

I guess that's why there are so many style specific yeasts produced by the likes of Wyeast or White Labs etc. It's not accidental. Certain styles really depend to a major degree on their specific yeast to give them their character.

To give you a specific answer to your question, what you propose can be done. For example, last year I did a series of brews from the one smakpak of WY1968, using the slurry in subsequent brews. In this order, I did a Mild, IPA, Stout, ESB, Best Bitter. It worked out fine, although the order I did them is theoretically not ideal. However, there's no way that yeast could ever be used for a Lager of any description. I ferment my Ales at 18 to 20°C, my Lagers at 9.5°C. An Ale yeast would go to sleep at Lager temperatures.

[squirt in the turns]

Hey warra, see what you mean about the order. I'm guessing Mild - Best Bitter - IPA - ESB - Stout, would have been better, depending on the actual colour of each beer. I've done this only once: an amber ale straight onto the slurry of a pale, which worked out fine.

Does gravity get any consideration when reusing yeast cake? And what effect does it actually have if you pitch yeast from a dark beer into a lighter one, other than affecting the colour?

[barrelboy]

Thanks Warra, appreciate the time spent and information.
Cheer BB

[warra48]

Hey warra, see what you mean about the order. I'm guessing Mild - Best Bitter - IPA - ESB - Stout, would have been better, depending on the actual colour of each beer. I've done this only once: an amber ale straight onto the slurry of a pale, which worked out fine.

Does gravity get any consideration when reusing yeast cake? And what effect does it actually have if you pitch yeast from a dark beer into a lighter one, other than affecting the colour?

From what I understand, it's best to go from the lower OG up to the higher OG.
Having said that, I think we tend to over complicate a lot of this stuff. I'm sure it will work just as well if you harvest from a 1.040 OG brew to pitch a 1.060 brew as it does the other way round. The main thing is really to ensure you have sufficient yeast. The higher the OG, the more you will need to pitch.

As for colour, you wouldn't really want to pitch the slurry from say, a Munich Dunkel into a Pils. It will probably have some effect of darkening the colour of the Pils to a degree, which isn't really what we want. If you're not concerned about colour, then just do what you fell like. Colour is all very well, but I brew for aroma and flavour. The way it looks and clarity is nice, but it's not the be all and end all.

[Tipsy]

I suppose a quick wash would solve the colour issue.

[warra48]

I suppose a quick wash would solve the colour issue.

Yep, would do the trick.