Trub and PH?

Ingredients
1

Do ya think that while taking PH reading that the amount of Trub in the test sample can cause “false” readings?  The last 2 batches i have made my post boil PH has actually went up a bit.  I take all my readings with a calibrated Milwaukee 101 at room temp. I attempt to be very consistent with my “processes” and tend to take the last sample of wort while transferring to fermenter with quite a bit trub in the sample. I suppose ill have to try and take a clean sample.

It must be user error.

Recipe: Vienna TYPE: All Grain
Style: Vienna Lager
—RECIPE SPECIFICATIONS-----------------------------------------------
SRM: 7.8 SRM SRM RANGE: 10.0-16.0 SRM
IBU: 24.3 IBUs Tinseth IBU RANGE: 18.0-30.0 IBUs
OG: 1.051 SG OG RANGE: 1.046-1.052 SG
FG: 1.013 SG FG RANGE: 1.010-1.014 SG
BU:GU: 0.477 Calories: 151.6 kcal/12oz Est ABV: 5.0 %
EE%: 73.00 % Batch: 3.25 gal      Boil: 4.90 gal BT: 60 Mins

—WATER CHEMISTRY ADDITIONS----------------
Starting Water (ppm):
Ca: 66
Mg: 20
Na: 27
Cl: 18
SO4: 36
HCO3: 262

Mash / Sparge Vol (gal): 2.62 / 3
RO or distilled %:       40% / 40%

Total Grain (lb): 6.0

Adjustments (grams) Mash / Boil Kettle:
CaSO4:                 0.5 / 0.6
CaCl2:                 1.2 / 1.4
MgSO4:                   0 / 0
NaHCO3:                  0 / 0
CaCO3:                 0 / 0
Lactic Acid (ml): 0.1
Sauermalz (oz): 0

Mash Water / Total water (ppm):
Ca: 84 / 84
Mg: 12 / 12
Na: 16 / 16
Cl: 69 / 69
SO4: 50 / 50
Cl to SO4 Ratio: 1.39 / 1.39

Alkalinity (CaCO3): 117
RA: 50
Estimated pH: 5.63 Actual was 5.44
(room temp)

Sparge PH 7.35 room temp. Ya thats high but my preboil PH was 5.52 and post boil was 5.6. all at room temp.

Total Grain Weight: 6 lbs 0.5 oz Total Hops: 1.10 oz oz.
—MASH/STEEP PROCESS------MASH PH:5.44

-ADD WATER CHEMICALS BEFORE GRAINS!!<<<<<<<
Amt                  Name                                    Type          #        %/IBU       
4 lbs 13.2 oz        Vienna Malt (Weyermann) (3.5 SRM)        Grain        1        80.0 %       
1 lbs 0.9 oz          Pilsner (2 Row) Ger (2.0 SRM)            Grain        2        17.5 %       
2.4 oz                Caraaroma (150.0 SRM)                    Grain        3        2.5 %

Name              Description                            Step Temperat Step Time   
Mash In          Add 2.64 gal of water at 166.9 F        152.0 F      60 min

—SPARGE PROCESS—

-RECYCLE FIRST RUNNINGS & VERIFY GRAIN/MLT TEMPS: 65.0 F/68.0 F
-ADD BOIL CHEMICALS BEFORE FWH
Fly sparge with 2.99 gal water at 168.0 F
Amt                  Name                                    Type          #        %/IBU       
0.85 oz              Hallertauer [4.30 %] - First Wort 60.0 m Hop          4        22.4 IBUs

—BOIL PROCESS-----------------------------
Est Pre_Boil Gravity: 1.039 SG Est OG: 1.051 SG
Amt                  Name                                    Type          #        %/IBU       
0.25 oz              Tettnang [3.80 %] - Boil 10.0 min        Hop          5        1.9 IBUs

2

I’ve never seen it happen and I can’t think of any reason why it should.

3

I don’t know of a reason why trub would affect pH either. However, I’m wondering how you are predicting the pH?  There are some methods that are better than others.

4

I use EZ water calculator spreedsheet 3.0. Thats all i have ever used and am comfortable with it. That being said i am consistently off by a few tenths of a point. I assume it’s because of my limited knowledge of RA and Alkalinity. I was hoping for some sort of Excel spreed sheet that would allow me to be dead on most of the time but i can see through practical application that Mash PH is a dynamic system and requires further “experimentation” on my end.

Thanks for the continued feedback on my multiple water ?s. It’s much appreciated and helps me wrap my pea brain around it.

5

That might be the problem.  I found EZWater to be pretty inaccurate.