PH adjustments to the Mash

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Jun 5, 2007
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I tried searching on it, but found nothing...

I've been brewing for a long time, and I think I tried to measure PH once at least a decade ago and found it to be fruitless (amber colored sweet wort+ stupid PH test paper= who the hell knows?).

Anyway, generally operated by the philosophy there is no such thing as a bad beer, so I wasn't too concerned if I didn't hit my target SG or FG... hell, if the color was off I didn't care. All I really cared about was making sure everything was nice and clean so my beer fermented with the yeast that I chose not some foreign nastys.... And that philosophy served me well for a long time.

However, now I'm thinking of taking my hobby to the next level. I want predictable, consistent, performance - maybe even enter a contest or two. So, I've been thinking about getting a bit more serious about my brewing, as an engineer that leads in only one direction - gather data then paralysis through analysis then do it again.

And I have been, taking meticulous notes on brewday and during fermentation, noting the ambient condions, timing, temperatures, etc., etc.

What I haven't gathered is grain lot data (wasn't available with my premixed grain bills), and chemical information (Mash PH, water charactaristics, etc.)

Should I measure PH of the mash? Should I try to adjust for PH?
Theoretically, if your grain and mineral profiles are correct, then your mash pH just falls into place. However, in practice, I just treat my water with Five Star 5.2 buffer and forget about pH.

jfliv said:
Should I measure PH of the mash? Should I try to adjust for PH?

Yes and Yes. Measure pH and correct it if necessary. I suggest that you should only correct the pH if necessary, especially if you build your own water. Read this as a primer.

Many brewers use Five Star's 5.2 to correct the pH w/o measuring it. I don't agree with this philosophy since you may be fixing a problem that doesn't exist or add more than necessary.

I agree with Kaiser - only treat your water if you know you have a problem. Most potable water works fine for most beers. The only time you are going to have problems is if you have extremes of water or are brewing really dark or really light beers.

I add gypsum or use 5.2 for extreme beers where I know my pH isn't going to be ideal. With 5.2 I use 1/4-1/2 the recommended amount and get my pH were I need it.

Ok... so I should attempt to control PH...

What's the best way to get a good sample? I have to admit in thinking about this, I've already identified a weakness in my brewing technique. I expect that in the mash the PH is not uniform, as the grist really doesn't circulate.

I don't generally stir the grist, but I was thinking that one would have to to ensure a represetative sample. By the same token, it makes sense to ensure no pockets of heat, or chemical anomoly etc.

Now, I just have to worry about heat retention... maybe it's time to retire the cooler tun in favor of something that I can more easily add heat to.