Fusels relative to strain?

[Lecterfan]

I am by no means up to scratch on my brewing science, but I have trawled the internet to (what I consider to be) a respectable degree before posing this question:

Is the production of fusel alcohols (if we ignore pH and other relevant factors) in terms of temperature relative to yeast strains?

Clearly I don't want to ferment my wy1272 at 32c (it happened once and I was left with very hoppy paint thinners), but I encourage my wy3724 to get up there for sustained periods of time. (yeasts used for demonstrative purposes, not asking only about these specific strains).

Is Belgian saison (wyeast say it's ok up to 35c) still full of 'usually undesirable' chemicals that contribute to the flavour profile of that particular beast when fermented at 35c, or would it take brewing it at ovee 40c to create the type of horrid shitstorm that the average ale yeast at 30c would produce?

I hope I have been reasonably clear.

I'm sure this is a "yes, if..." or "no, but..." type of question, but if someone could wade through my swamp of ignorance and do their best to provide me with an informed answer, well, that would be damned decent of you!

Cheers.

 

[Mattrox]

I don't have the definitive answer, but the question you posed is interesting. And I think you asked it clearly.... well, I reckon I understood what you were asking.

Essentially the metabolic by-product of anerobic respiration is ethanol and carbon dioxide, but there are a whole host of other compounds produced which contribute to flavour (good and horrid). My best guess is that different yeast strains have different metabolic pathways due to the different set of enzymes their DNA codes for. Each unique set of enzymes produces unique sets of compounds. If a yeast is used outside of its optimal temperature range the enzymes work inefficiently. The different enzymes will behave differently when too warm therefore different yeats strain should produce different "off flavours". Not sure about the other alcohols produced though.

 

[Byran]

Again, no definitive answer.
But I have read about the so called "danger zone" when referring to food storage temperature , would it be possible for a higher temperature , relative to the yeast strains optimum temp create an environment more susceptible to the dominance of undesirable biological nasties? Eg. high temp causing the yeast to do less work, but the bacteria and other yeast that like that temp range, taking over creating the off flavours deemed due to brewers yeast high temp stress?

Just a thought.

 

[labels]

I also can give no definitive answer. Saccharomyces cerevisiae, commonly used ale yeast of which there are many different strains still remains Saccharomyces cerevisiae. How much difference there is in producing fusels is unknown as far as I know. Because they are still of all the same genre it could not be as great as one might think. Unknown

-=Steve=-

 

[Nick JD]

Is Belgian saison (wyeast say it's ok up to 35c) still full of 'usually undesirable' chemicals that contribute to the flavour profile of that particular beast when fermented at 35c, or would it take brewing it at ovee 40c to create the type of horrid shitstorm that the average ale yeast at 30c would produce?

This strain seems to require a higher temperature to maintain normal metabolism. It's estery, but no more so than other Belgians.

That it doesn't chuck fusels is more to do with its ability to fall asleep at 25C than anything - and I'd guess that it has a mutation causing a shift in one of the many metabolic pathways resulting in hot fermentation being a prerequisite rather than a problem. Probably something temperature dependant is a bit retarded, and so are the resulting fusels.

 

[hoppy2B]

SN9 is good for fusels. I've used it for my last couple of ales and found it quite nice.