The REAL mash pH?

[Cliff]

The pH is going to change depending on what you put in the mash.

Do a Decoction with oats some time and check it before and after.
Do a pH test before and after adding the water to the grain bed.
Do it using Marris otter and do it using six row and again using two row briess
It'll all seem pretty straightforward once you do a few tests.
After a while you'll just know what your ingredients will do to the mash. If you are fortunate enough to use water from your own well your acidity and mineral will remain constant over long periods of time. So you'll be able to toss all those gizmos in the bottom of a drawer and forget 'em.

[TimmyR]

AJ - here are the results from yesterday's batch. Recalibration certainly was worth it. I should have measured more often, but my one pH measurement was at approximately 20 min into the mash; 5.45 @ 27.5C.

My last water report (2010)

64 Ca++
26 Mg++
31 Na+
221 CO3--
54 SO4-
57 Cl-

I blended this with distilled water 50%/50%. My additions were 14g Gypsum, 1g Epsom Salt, 2g Calcium Chloride.

I just wanted to follow-up, see what you think and say thanks for all the info. The pH meter was cryptic to me when I first received it, much like my refractometer was, and now I am finding it invaluable.

Date: 7/4/11

Size: 14 gal
Efficiency: 83.0%

Original Gravity: 1.068 (1.056 - 1.075)

26.9 lb American 2-row
2.24 lb Carapils®/Carafoam®
17.95 oz Crystal Malt 40°L
1.43 lb White Wheat Malt
13.4 oz Acidulated Malt (Weyermann)

Mash In - Liquor: 12.0 gal; Strike: 165.19 °F; Target: 151.0 °F
Mash Out - Target: 165.0 °F

[ajdelange]

Looks good to me. This is how it's supposed to work.

[TimmyR]

Victory. Do you have any book suggestions for basic chemistry? My reading list is full now, but given the time I'd like to reacquaint myself with chemistry as it applies to brewing.

Thanks again.

[ajdelange]

Do you have any book suggestions for basic chemistry? My reading list is full now, but given the time I'd like to reacquaint myself with chemistry as it applies to brewing.

Your use of the word "reacquaint" causes me to assume that you have studied chemistry at some time in the past. In that case I guess I'd suggest checking with Amazon for a basic college text to use more as a reference than a primary source and hitting the chapters on law of mass action/ionic equilibrium as it is understanding of that subject which is most important in understanding water chemistry.

But there is more to it than water chemistry and, interestingly enough, the key concept of water chemistry is the Henderson-Hasselbalch equation which seems to be presented most clearly in biochemistry texts so I'd get a modern biochem text and start with Henderson-Hasselbalch (which is going to be near the front) and then move on to fermentation and then proteins.

[TimmyR]

Correction....acquaint versus reacquaint. I have no formal chemistry education except for what little I remember from high school / college and some basic exposure at the Siebel Concise Course.

Good catch AJ.