Author Topic: Unfermentable, da-dee-dee-da  (Read 1715 times)

Offline denny

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Re: Unfermentable, da-dee-dee-da
« Reply #15 on: July 18, 2011, 10:41:40 AM »
I've checked my own pH and that of a few other brewers and never seen anything other than a very minor, not-to-worry-about pH increase.  But I've heard from a few people that they do get large increases.  Obviously, it will depend on your water, but for most people it shouldn't be an issue.
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Offline richardt

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Re: Unfermentable, da-dee-dee-da
« Reply #16 on: July 18, 2011, 11:04:01 AM »
Agreed.  But you have great water.

Those, like me, whose tap water has high bicarbonate (and alkalinity) concentrations would likely notice significant pH issues with sparging (or even steeping, if using extract+grains), i.e., pH rising.  Results in crappy tasting beer. 
Kirk, you have to know your water profile and figure out what will work for you.  FWIW, you'll notice less pH increase during sparging if you're using RO, distilled, or "spring water".  I prefer to build from scratch using RO water and brew salt additions.
You can predict the effect of all this by using Martin's Bru'n water calculator.

Offline tomsawyer

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Re: Unfermentable, da-dee-dee-da
« Reply #17 on: July 18, 2011, 01:58:36 PM »
Why would 0.4 pH increase during a sparge result in crappy tasting beer?  The mash is done at the right pH, you're just rinsing sugar with the sparge.  If you are in the right range to begin with its not going to put you into the 6.0+ range where I understand theres issues with extraction of tannins.

Just another reason to do no-sparge!
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Offline narcout

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Re: Unfermentable, da-dee-dee-da
« Reply #18 on: July 18, 2011, 03:12:04 PM »
You don't use up buffering power.  They're salts in the mash water, and the water stuck to the grains has the same concentration as the free mash liquor.  Usually around 25% of the water stays behind in the grain (1/2 qt/lb when mashing with 2 qt/lb), and those buffers (primarily phosphate) proceed to buffer the sparge.

I guess I'm not quite following you here.  There's only so much alkalinity a certain quantity of grain can neutralize with malt phytin right? 

For what it's worth, the beers with the high sparge pH turned out just fine.  I haven't entered many beers in competition (maybe 17 or 18), but I don't think I've ever gotten dinged for astringency or tannins.  Maybe this is due to the short duration of a batch sparge?

Anyway, it's easy enough to correct.