low Ph on this mash...WHY?

[gizmodog51]

hello,

i started all grain about 1 1/2 years ago with BIAB. my wards water report basically showed i could brew anything but could use a little calcium chloride to bring the mash Ph into the sweet spot 5.1-5.4.

well yesterday i brewed a 20 lb pale malt batch with 1 lb of 120 carmel & .5 lb of 90 carmel with about 3.5 oz of sauermaltz which i have read does the same thing as lactic acid with bringing in the Ph into the sweet spot.

well it went badly.....the Ph was never any higher then 4 range. i got desprate/panicked and added some gypsum which is supposed to up the Ph.

normally i don't use gypsum because i can taste the hop sharpness it imparts in the brew even though the H2O report list SO4 at the 6 rating.

i just want to clear my head and understand why this happened? is it because the roasted grain was enough to acidfy the mash and using the sauermaltz put it over the top?

thanx for any help.......

gizmodog

 

[ajdelange]

i started all grain about two years ago with BIAB. my wards water report basically showed i could brew anything...

You can, with occasional exceptions, brew almost any beer with almost any water if you treat the water right (which often involves dilution with so much RO water that you might as well use straight RO with mineral additions)

...but could use a little calcium chloride to bring the mash Ph into the sweet spot 5.1-5.4.

It usually takes a lot of calcium to have much effect on mash pH but as I have no idea what your water is like nor how much a 'little' calcium chloride is I can't comment further.

The 'sweet spot' is probably 5.4 - 5.5 (at room temperature). 5.2 - 5.6 (at room temperature) is the OK band.

well yesterday i brewed a 20 lb pale malt batch with 1 lb of 120 carmel & .5 lb of 90 carmel with about 3.5 oz of sauermaltz which i have read does the same thing as lactic acid with bringing in the Ph into the sweet spot.

well it went badly.....the Ph was never any higher then 4 range.

I can only get a rough estimate as to how your malts would behave using a mix of Kai Troester's data and mine and assuming RO water and 100 mg/L calcium from your additions the mash pH should be about 5.46. If your water has typical alkalinity of 75 it would be more like 5.5.

i got desprate/panicked and added some gypsum which is supposed to up the Ph.

As it contains calcium it actually lowers pH somewhat but, as noted earlier, not by much.

If you give me more details on the water I can give you a bit more detail but it appears that there was a problem with pH measurement. How do you measure pH?

 

[gizmodog51]

yeah i apologize i was off on the ph sweet spot....

here's my water report
Ph 7.8
TDS 200
Sodium. NA.... 11
Potassium. K.... 2
Calcium,Ca..... 48
Magnesium, Mg. 8
Total hardness, 148
Nitrate, NO3-N .06 safe
Sulfate: SO4-S. 6
chloride, Cl..... 14
cabonate, CO3..>1
bicabonate, HCO3..168
Total Alkaninityt, CaCO3..148

i usually start with about 1/2 teaspoon of calcium chloride to bring Ph into range. i usually brew belgian beer pales....dubbels, wits..saisons...

yeah i know it a bummer...i use pricision labs test strips....#4662

thanx for your reply.
GD51

 

[ajdelange]

With those numbers and making some assumptions about your water to grist ratio we can get estimates of where the protons flow. The numbers below are deficits i.e. the number of protons absorbed in order for individual grist components to come to mash pH. If the number absorbed in negative then it represents the number thrown off. All numbers are in milliequivalents:

Water's alkalinity (carbonate and bicarbonate): 38.62 mEq
Protons from Ca/PO4 reaction: -20.57
Protons from Mg/PO4 reaction: -1.39
Absorbed by base malt: 44.59
Absorbed by 90L Caramel: -11.95
Absorbed by 150L Caramel: -16.65
Absorbed by Sauermalz: -32.65

These sum to 0 at pH 5.51 which is the estimated pH for this mash.

We could argue as to whether any of the malt parameters I used accurately represent your malts and so the estimate is subject to error. But it is instructive, IMO, to see which mash components are the proton suppliers and which the absorbers as the relative contributions/deductions they make.

Test strips typically read 0.3 or more low so supposing that my estimate is 0.1 high you should still be over 5.

 

[gizmodog51]

With those numbers and making some assumptions about your water to grist ratio we can get estimates of where the protons flow. The numbers below are deficits i.e. the number of protons absorbed in order for individual grist components to come to mash pH. If the number absorbed in negative then it represents the number thrown off. All numbers are in milliequivalents:
Water's alkalinity (carbonate and bicarbonate): 44.59 mEq
Protons from Ca/PO4 reaction: -20.57
Protons from Mg/PO4 reaction: -1.39
Absorbed by base malt: 44.59
Absorbed by 90L Caramel: -11.95
Absorbed by 150L Caramel: -16.65
Absorbed by Sauermalz: -32.65

These sum to 0 at pH 5.51 which is the estimated pH for this mash.

We could argue as to whether any of the malt parameters I used accurately represent your malts and so the estimate is subject to error. But it is instructive, IMO, to see which mash components are the proton suppliers and which the absorbers as the relative contributions/deductions they make.

Test strips typically read 0.3 or more low so supposing that my estimate is 0.1 high you should still be over 5.

thank you kindly for this very scientific report.

what actually went wrong? using the sauermaltz with the dark grain?
i don't have any programs to determine the results you obtained. i would just like to know what i can do using the resources i have I.E. water report, common additives and tests strips to try and avoid this again. this is the first time i have experienced this problem...and have brewed 15+ batches...the last four being 10 gallon.
on this batch were are discussing the water amount was 12 gallons.....
grain bill was 21.5 lbs.....did an acid rest 120, (10m) then mashed at 149 (90m) and M.O.at 170, (10m).
cooled with a immersion cooler and collected 5 gallons in two carboys.

learning to brew, the only way to achieve self esteem!

thanx for your help and for your resources and brains.........
GD51

 

[ajdelange]

Before moving on to you questions note that I made a typo last night. The proton deficit of the water would be 38.62 mEq.

what actually went wrong? using the sauermaltz with the dark grain?

Nothing went wrong. You should get a pH around 5.5 ±.1 or .2 from bad assumptions, differences between the malts you used and the malts I modeled etc. The numbers show that the sauermalz just about neutralizes the alkalinity of the water leaving the two dark malts and the calcium derived protons to balance out the base malt's proton requirement. Were you to leave out the sauermalz the expected pH would rise to 5.58. You are getting bad pH readings because you are using strips which just don't seem to work with beer. Fortunately you responded by adding gypsum which would lower pH whereas most guys would have thrown in a tbsp of chalk. Thus the beer should be OK as the gypsum probably didn't lower the real pH to less than 5.35 at worst.

i don't have any programs to determine the results you obtained.

Perhaps not at the moment but you can have the spreadsheet I used if you want it. It is at
http://www.wetnewf.org/pdfs/Brewing_articles/MashpH.xlsx

Depending on how much water (or other) chemistry you know this may be a bit much for you. The spreadsheet is not very polished at this point, only accepts metric units.... If you do download it be sure to get and look at the presentation I gave when I presented it to brewers two weekends ago. The slides are at:
http://www.wetnewf.org/pdfs/Brewing_articles/MBAA_FREDERIC.pptx

i would just like to know what i can do using the resources i have I.E. water report, common additives and tests strips to try and avoid this again.

The only way to prevent this from happening again is to stop using pH strips. If this means not measuring pH then don't measure pH. As we said earlier, most brewers would have responded to a pH measurement like the one you got in a way that would have ruined the beer. Buy a pH meter. If you don't want to do that then you must either totally ignore pH by doing something like using the Primer recommendations or rely on pH predictions computed by spreadsheets or calculators like the one I'm using or one of the many others. These will get you into the ballpark.

 

[SpeedYellow]

Gizmodog- abandon this concept of using minerals to affect pH, because it's outdated and largely wrong. Minerals have much more impact on flavor than on pH, so treat them as a flavor ingredient. To reduce pH, use acids or acid malt.

 

[ThreeSheetsBrewing]

Are your strips old or stored improperly? They are notorious in the medical field for going bad and giving crappy results.

 

[gizmodog51]

Before moving on to you questions note that I made a typo last night. The proton deficit of the water would be 38.62 mEq.


Nothing went wrong. You should get a pH around 5.5 ±.1 or .2 from bad assumptions, differences between the malts you used and the malts I modeled etc. The numbers show that the sauermalz just about neutralizes the alkalinity of the water leaving the two dark malts and the calcium derived protons to balance out the base malt's proton requirement. Were you to leave out the sauermalz the expected pH would rise to 5.58. You are getting bad pH readings because you are using strips which just don't seem to work with beer. Fortunately you responded by adding gypsum which would lower pH whereas most guys would have thrown in a tbsp of chalk. Thus the beer should be OK as the gypsum probably didn't lower the real pH to less than 5.35 at worst.


Perhaps not at the moment but you can have the spreadsheet I used if you want it. It is at
http://www.wetnewf.org/pdfs/Brewing_articles/MashpH.xlsx

Depending on how much water (or other) chemistry you know this may be a bit much for you. The spreadsheet is not very polished at this point, only accepts metric units.... If you do download it be sure to get and look at the presentation I gave when I presented it to brewers two weekends ago. The slides are at:
http://www.wetnewf.org/pdfs/Brewing_articles/MBAA_FREDERIC.pptx




The only way to prevent this from happening again is to stop using pH strips. If this means not measuring pH then don't measure pH. As we said earlier, most brewers would have responded to a pH measurement like the one you got in a way that would have ruined the beer. Buy a pH meter. If you don't want to do that then you must either totally ignore pH by doing something like using the Primer recommendations or rely on pH predictions computed by spreadsheets or calculators like the one I'm using or one of the many others. These will get you into the ballpark.

thank you, thank you, thank you! i will look at the presentation . probably will be over my noodle but i'm a sponge and can absorb .....understanding is another matter...LOL!.

sincerely,
the hokey home brewer...
GD51

 

[gizmodog51]

Gizmodog- abandon this concept of using minerals to affect pH, because it's outdated and largely wrong. Minerals have much more impact on flavor than on pH, so treat them as a flavor ingredient. To reduce pH, use acids or acid malt.

thanx , i used sauermaltz to correct Ph and along with the roasted grains it kinda got outa hand .....and may be my test strips are old?? no telling how long they sat on the LBS shelves before i purchased them.

thanx for your reply.......
gd51

 

[gizmodog51]

Are your strips old or stored improperly? They are notorious in the medical field for going bad and giving crappy results.

just kept in the snap cap container at room temps.......guess i need to seek out a decent Ph meter.....anyone got a recommendation?

thanx,
GD51

 

[SpeedYellow]

I'm not convinced that old ColorpHast strips read any different from newer strips. I have some several years old, and they read 0.4 low just like strips I bought last year. The 0.4 low has been pretty consistent over several batches where I've compared.

 

[ajdelange]

To really put all this into perspective we have to recognize that many a brewer has gotten a completely hokey pH reading from a digital meter and wound up ruining his beer by chasing that erroneous pH. Came from a digital meter - it must be right! A pH meter is a tool that requires some experience of its operator with regard to proper care of the electrode, calibration, cleaning etc. As that experience is gained the erroneous readings mysteriously become more and more rare and if one does pop up the experienced operator immediately recognizes it as not fitting the conditions and takes corrective action.

Inexpensive meters are notorious for poor stability e.g. a meter reads 5.65 one minute and 5.85 15 minutes later. The user must know how his meter behaves in this regard and be prepared to recalibrate as often as it takes.