having perplexing PH issue

General Homebrew Discussion
1

Need some input with a consistent lower than projected PH. my RO water has PH of 5.5, not abnormal and even though its acidic, it should not have any buffering capacity (TDS 12 today).

Brunwater has predicted my mash to be 5.41, and it came out 5.2. two PH meters both calibrated and both reading the same. PH strip used to verify and it also read around 5.2. been having this issue for 4 months or so…always coming in .2 or so lower than projected with brunwater regardless of the brew recipe. any ideas welcome…getting frustrated.

here’s todays recipe:
  grain              cat        lbs.  ounce  Lovi

munich light base      3.0 0.0 5
pilsner base      4.0 0.0 2
caramunich crystal    0.0 8.0 47
biscuit crystal    0.0 3.0 23
melanoiden roast      0.0 3.0 30
munich base      4.0 0.0 10

water to grain ratio: 1.77
est color: 10.6
mash water 5.25 gal: .8 gypsum, 2.6 epsom, 2.6 cal chloride
sparge water 4.25 gal: .6 gypsum, 2.1 epsom, 2.1 cal chloride

amber balanced profile : 46 calcium, 13 mag, 8 sodium, 74.7 sulfate, 67.8 chloride
projected PH 5.41
actual PH 5.2

2

I remember you posting on this and I asked about your water volumes, so it sounds like there are no issues there. Do you weigh out your own grains or does your LHBS ?  There could be inaccuracies there which could throw things off a bit.  And maybe inaccuracies in the scale you use to weigh out salts ?  Past these things, I’m running out of ideas !

3

good questions. i weigh all my grains just to check, and calibrate the scale. for my salt additions, i also weigh using digital scale and calibrated yesterday before using.

4

Is the mash sample cooled to 70?  Mine routinely comes in .05 to .1 lower than Brunwater and I use 100% distilled, so I keep that in mind when creating my spreadsheet.

5

yes i sample off from mash making sure no grain in the sample, and cool it in ice bath to 68-70F before reading.

6

How are you pulling your sample?  Today I pulled a sample from the mash draining ball valve, got 4.98,  pulled a sample from the top of the mash with the strainer/eyedropper method got 5.51,  gave it a good stir got 5.35.

Sounds like you are bypassing the calcifier on your RO system?

7

yes mixing mash thouroughly and at about 5 minutes taking sample, draining it from grain into sample cup and cooling.

not sure what you mean by bypassing calcifier. i have 3 filter RO system- sediment filter, carbon, RO filter.

8

They sometimes have a calcifier inline to raise your pH for protecting plumbing and fixtures from the acidic  pH 5.5 of pure RO.

I been having the same problem using RO using both Martin’s & Kai’s spreadsheets…sometimes dead on, next time off .1-.2

9

well you having the same issue makes me feel better! feel like im going crazy. i’d like to figure out why its happening, even though its correctable during the mash.

10

Another thing - lovibond ratings do fluctuate even within the same maltster. For example, Northern Brewer’s Weyermann Melanoidin malt is listed at 23-31L. Many malts are listed this way. That difference of 8L for the same malt could definitely affect your pH. The higher the L number, the more acidic to pH.

11

i hear ya. i have it at 30L. even if you switch mela to 60L from 30L only moves PH .01. for this significant of PH variance, it would have to be the base malt(s) being significantly different LB than the range. I do tend to error on the high side for this very reason of LB variability.

12

Yeah, I get that on the small amount of melanoidin. Just meant in general that for the whole grist it’s possible to be off a little on real vs stated L numbers. I honestly think that it’s a combination of a few things being off only a slight amount - weights, L numbers, volumes, etc., to move pH a bit. Obviously your process looks pretty sound to me.

13

yeah agree. its just frustrating when you cant dial in the reason for the variance. going to try distilled water with same recipe and see if i can correlate the variance to the RO water.

14

I hear you, I feel the same when there’s an issue. And honestly, very few people here have true lab grade equipment to measure large and small ingredient amounts, pH and water quantity with real precision. Then add that malts can vary in their stated color ratings and it can be really tricky sometimes. But we make beer that looks and tastes great so I guess we must not be too far off !

15

How are you adding your salts - Do you add them all to the mash, add them all to your total water volume of 9.5 gallons or split them up?

16

see my 1st post…

17

Funny i have had the same issue for a long time now myself. I have determined that it is mainly when i buy a new bag of grain or a different malt.  There seems to be a variance in PH between new bags/malts however not by much. I use to use EZ water and you can change the distilled water PH value of each grain of which i did for a while and it’s just a big pain in the rump. Brunwater is by far the best i think.
I recall some of your previous post and we seem to have the same processes, Funny. Anyway i tend to always shoot a little higher (5.6 room temp) and it works. I have become better at adjusting on the fly and its been fun. good luck wish i could help.

18

EZ Water is better than nothing but I did not get particularly great results using it. It was likely in part user error based upon the water profiles I was targeting rather than the tool itself. Bru’n Water is certainly a superior tool if for no other reason than the ability to input the grains and have it account for how they affect the mash ph.