Isolate mash PH impact

[Morrey]

If for example we started with neutral water, maybe I'm saying this wrong, but looking for the isolated impact that ph has on the mash process. Considering all other elements are adjusted properly, if there is such a thing, what isolated function does ph play?

 

[MaltMaker]

pH does *not* have just one isolated function in the mash nor does it play one major role, instead it has many signifcant roles.

There is a list of how the pH affects the mash here:

http://braukaiser.com/wiki/index.php?title=How_pH_affects_brewing

Not all are applicable to the mash but the mash is where it begins:

• The enzymatic activity in the mash is increased as all important enzymes get activated. (except for alpha amylase which starts to suffer at a pH below 5.6)
• More zinc, an essential yeast nutrient, goes into solution
• The extract yield (efficiency) is improved
• The protein coagulation and precipitation is improved (improved break formation)
• The redox potential is improved which results in a lower susceptibility to oxygen.
• The run-off speed is improved
• The color increase during the wort boil is reduced
• Better trub precipitation and faster pH drop lead to faster fermentation and greater attenuation of the beer.
• Lover viscosity improves filterability
• The taste of the beer is more rounded, fuller and softer. The beer is crisper, more fresh and shows more character.
• The hop bitterness is more pleasant and doesn't linger
• The foam is more stable and denser
• The color of the beer is lighter
• Mash oxidation is reduced since the main culprit, the lipoxigenase enzyme, doesn't work well at low mash pH conditions
• Haze stability is improved
• Beer digestion is stimulated. This is a positive effect of the lactic acid
• Susceptibility to microbial spoilage is reduced through Lower beer pH: beer spoilage organism don't grow below a pH of 4.4
• Higher attenuation

If you mean what does adding grain to a neutral water do, then all grains acidify and drop the pH. There are various benefits at different pH values.

 

[Morrey]

pH does *not* have just one isolated function in the mash nor does it play one major role, instead it has many signifcant roles.

There is a list of how the pH affects the mash here:

http://braukaiser.com/wiki/index.php?title=How_pH_affects_brewing

Not all are applicable to the mash but the mash is where it begins:

• The enzymatic activity in the mash is increased as all important enzymes get activated. (except for alpha amylase which starts to suffer at a pH below 5.6)
• More zinc, an essential yeast nutrient, goes into solution
• The extract yield (efficiency) is improved
• The protein coagulation and precipitation is improved (improved break formation)
• The redox potential is improved which results in a lower susceptibility to oxygen.
• The run-off speed is improved
• The color increase during the wort boil is reduced
• Better trub precipitation and faster pH drop lead to faster fermentation and greater attenuation of the beer.
• Lover viscosity improves filterability
• The taste of the beer is more rounded, fuller and softer. The beer is crisper, more fresh and shows more character.
• The hop bitterness is more pleasant and doesn't linger
• The foam is more stable and denser
• The color of the beer is lighter
• Mash oxidation is reduced since the main culprit, the lipoxigenase enzyme, doesn't work well at low mash pH conditions
• Haze stability is improved
• Beer digestion is stimulated. This is a positive effect of the lactic acid
• Susceptibility to microbial spoilage is reduced through Lower beer pH: beer spoilage organism don't grow below a pH of 4.4
• Higher attenuation

If you mean what does adding grain to a neutral water do, then all grains acidify and drop the pH. There are various benefits at different pH values.

Valuable information and a great read!

Based on the fact that Ph allows many desirable "things" to happen, I am going to draw a parallel and ask if you feel this is accurate:

I have large fields where I raise Coastal Bermuda hay for livestock. My soil tends to be acetic so I test and apply lime annually to adjust the ph. When ph is properly adjusted, the plants will readily absorb available nutrients (the fertilizer I apply) and grow nicely. If the ph is too acetic or not within a specific range, no amount of fertilizer I could apply will be absorbed or utilized by the plant. Ph per se "unlocks" the ability for many other things to occur.

I realize brewing is not hay raising, but the way I see it, ph is not the magic bullet, but allows all the desirable things we wish to happen to occur. Right?

 

[MaltMaker]

That is correct! Now the question is do you rotate your grass to other crops? That is a common practice where I live as each crop restores something the others take from the soil.

 

[Morrey]

That is correct! Now the question is do you rotate your grass to other crops? That is a common practice where I live as each crop restores something the others take from the soil.

Absolutely crop rotation is of tremendous benefit locally. The hay (grass) I raise is actually "plugged" or sodded making it more of a permanent "crop" similar to the grass in our lawns. This makes ph management even more critical since we have no other beneficial crop to rotate with.

One more question and I am at peace with my quest for ph relationships in mashing and brewing-I have read in posts and some other readings, that mash efficiency is not ph related. But I think I disagree to some extent. Ph is just one of the factors relating to good conversion, but a necessary element if I am thinking correctly. Not saying ph is all there is to it, but since everything interrelates, I suspect that if ph is way out of range that red flag could possibly impact efficiency/conversion. Right?

 

[ajdelange]

pH modulates many biocehmical reaction many of which have pH optima (i.e. values at which they go to completion fastest or most completely or both. As none seem to be at the same pH there are tradeoffs. For example the lower the mash pH the better the bacterial stability of the brew but many think low pH beers taste sharp.

 

[Morrey]

AJ, referencing your Bru'n Water program I use, what is considered a low ph beer?

 

[ajdelange]

You are confusing me with Martin. Of the two of us he is the better looking one.

That aside I should have said low pH mash. Actual beer pH is set more by the yeast than anything else though of course mash pH has some effect.

 

[Silver_Is_Money]

I believe that the average finished beer has a pH of about 4.15, give or take a bit.

Brulosophy mashed (side by side) one beer at pH 4.45, and another (identical recipe) beer at pH 5.30, and after the end of fermentation they both had nearly identical pH readings. Fairly close to 4.15 as I recall.

 

[ajdelange]

4.15 would be towards the low end for ales (though some go lower) whereas lagers tend to minimize around 4.4. I'd guess the average beer would have a pH at about 4.4

 

[Morrey]

You are confusing me with Martin. Of the two of us he is the better looking one.

That aside I should have said low pH mash. Actual beer pH is set more by the yeast than anything else though of course mash pH has some effect.

Lordy Lordy, so y'all are not one in the same after all! J/K. Apologies, I completely glazed over on that one.

Interesting about the impact the yeast has on the finished beer. I have read that really aggressive dry distillers yeast used in making mashes to be distilled has a big impact on the "wash" ph. So the ensuing impact of low ph can be a harshness or sharpness in the distilled product. Good info AJ, always learning.

 

[Morrey]

I believe that the average finished beer has a pH of about 4.15, give or take a bit.

Brulosophy mashed (side by side) one beer at pH 4.45, and another (identical recipe) beer at pH 5.30, and after the end of fermentation they both had nearly identical pH readings. Fairly close to 4.15 as I recall.

Pretty good info here! I have never done this, but wonder if the CO2 bubbles from a carbed beer would mess up the ph readings on a meter like my Hach Pocket Pro? I have wanted to read the ph on some various sour beers and always wondered how to get the most accurate readings??

 

[ajdelange]

Yes it will. CO2 bubbles come from carbonic acid which breaks apart into CO2 gas and water thus causing beer pH to rise. Degass the beer before measuring pH (not to mention the fact that CO2 bubbles on the bulb and junction render their effective areas less).

John P asked me once to calculate the expected drop if the beer is not degassed and though it's been a while I think I got, based on average condition levels, about 0.1 pH.