Has anyone considered that each yeast strain might prefer a particular pH?

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SpeedYellow

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Current consensus seems to be that we should target a mash pH of about 5.2-5.6 because of what's happening in the mash tun. But I've made some superb beers at the extremes of this range (5.0 and 5.8) and some stinkers right in the middle. I've struggled to understand what makes some beers good if I've completely flouted the mash pH rules, or bad when I've followed them.

So is it possible that we should be looking at what our selected YEAST wants, not the mash? Perhaps certain strains want a low (or high) pH?
 
I think that some strains (ale) like a lower pH than others (lagers) and assume that is why ales generally have lower pH than lagers but I assume that the yeast themselves set the pH to the range they want. It is the yeast, after all, that secrete the acids responsible for the lowering of wort pH from a little over 5 to something between 4 and 4.7. I assume there is a regulatory mechanism in play i.e. that they stop secreting when they get it where they want it to be.

But this doesn't mean that we shouldn't keep an eye on kettle pH. I suppose we could reason that it would be easier for the yeast to reach the desired pH if they were given low pH wort as they would then not have to produce as much acid relative to how hard it would be for them to pull a high pH wort low. OTOH too low a mash pH might have other detrimental effects on the quality of the wort. Keeping the yeast happy isn't the only reason to control pH.

Of course there are lots of other ways to screw up a beer beyond improper mash pH. Getting that right is a sine qua non but it is not a guarantee. A mathematician would call it a necessary but not sufficient condition.

All the foregoing is pure speculation on my part. I can't back it up with any references or even experiences so consider that in pondering it.
 
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