Do yeast manufacturers post actual attenuation or apparent attenuation figures for yeast strains on their websites? Neither the Wyeast FAQ’s page nor quick searches on Google and the AHA forum gave me the answer.
Click on any strain and you will find the attenuation.
http://www.wyeastlab.com/hb_yeaststrain.cfm
You can just scroll for White labs.
http://www.whitelabs.com/beer/homebrew_strains.html#ALE_YEAST
Well, actually kinda neither. The figures that manufacturers publish are simply a way of comparing on strain to another using a standardized wort. They may or may not be an indication of the attenuation you can expect. That’s dependent on things like recipe and techniques.
I should’ve been more clear. I was referring to whether these figures were actual or apparent. So it looks like neither. Are the manufacturer provided attenuations even useful for comparison with my apparent attenuation?
It’s apparent attenuation but as Denny said it’s only really useful for comparing one strain to another on paper.
Not IMO. OK, maybe a bit…personally, though. I don’t even look at or consider the manufacturer figures. I can get 60% or 90% attenuation out of the same yeast depending on the wort.
I see I should have had more coffee.
Agreed with the other posters here. The number is apparent attenuation, but it’s more if a relative measurement. You could likely get close to that if you mash at 150°F, pitch 10 million cells per ml into a 10°P wort and ferment at 20°C, but chances are that’s not the beer you are going for.
Recently I did a matrix of 40 fermentations with wort gravities from 3°P to 15°P and inoculations rates from 30 million per ml to 120 million per ml and was quite surprised by the variation in attenuation.
Data will be on my blog soon.
Looking forward to seeing it.