Is a 4.79 Mash pH too low?

[W0rthog]

In an effort to get my mash pH down to 5.3~, I calculated my water and added 5oz of acidulated malt to drop it. This was in accordance with the advanced water tool calculation on Brewers Friend. My protein rest yielded 4.45, while my Sac rest at 147deg measured 4.79 pH.

Are there any know issues with a mash pH this low?

I'm using my pH meter for the first time and it came with a calibration verification, so I assume it's accurate out of the box.

Thanks in advance.

 

[mabrungard]

Well yes, that pH is too low. However, there is a good chance that the meter's calibration could be off...regardless of the verification. Meters need to be calibrated prior to each session to assure that it is operating and reporting properly.

Issues with pH that low can include a loss of body and increased level of fermentability. An important issue could be a tart or acidic flavor for the beer. But, don't worry. It will still be beer.

 

[ajdelange]

In an effort to get my mash pH down to 5.3~, I calculated my water and added 5oz of acidulated malt to drop it. This was in accordance with the advanced water tool calculation on Brewers Friend.

Use the calculators to get a rough idea as to what to expect and to study the effects of adding different grains, changing water alkalinity etc. but do not rely on them for accurate mash predictions. As a rule of thumb 1% sauermalz will drop the mash pH by 0.1 pH but this is a rule of thumb - not a super accurate predictor. Before using more than 3% sauermalz make a test mash with and without the sauermalz.

My protein rest yielded 4.45, while my Sac rest at 147deg measured 4.79 pH.

Are there any know issues with a mash pH this low?

Just that the beer won't be as good as it might otherwise have been. Some will tell you that if the mash pH is too low the beer will taste sour. There is little truth in this as the yeast tend to set the beer pH where they like it with strong disregard for the pH at which wort is presented to them though obviously their ability to control pH depends to some extent on this.

I'm using my pH meter for the first time and it came with a calibration verification, so I assume it's accurate out of the box.

A pH meter, as is the case with any new tool, has an associated learning curve. As apparently your meter did not come with adequate instructions you might want to take a look at https://www.homebrewtalk.com/f128/ph-meter-calibration-302256/ for some tips on how to use one and check its calibration and stability. No, you cannot assume it is accurate out of the box. You can only assume it is accurate right after a proper calibration. Some of the less expensive instruments are not capable of being calibrated properly but there are workarounds (see the link).

 

[revansCAAD8]

Huh also, did you check the mash ph at room-temprature, not mash temp? Mash temps could damage &/or shorten the probe life and affect ph results.

 

[hoppybrewster]

I hope I'm in the right place for this question. Going from extract to AG so I'm starting to pay closer attention my well water. Bought a water test kit and everything tests within range except PH. Now I don't have a fancy meter, just the strips. It's a wide range one at least. I'm getting numbers in the low to mid 4's. So I bought that PH stabilizer that suppose to put it at or just above five. My confusion is should the mash be 5 ish or the water right out of the tap? I put this stuff in my water out of the tap and it doesn't seem to budge the numbers.

 

[ajdelange]

I hope I'm in the right place for this question. Going from extract to AG so I'm starting to pay closer attention my well water. Bought a water test kit and everything tests within range except PH.

The pH of the water is not important (relatively speaking). What is most important is the alkalinity and then calcium, magnesium, chloride and sulfate ion contents. Instead of using a hardware store kit invest the money in a test from Ward Labs.

Now I don't have a fancy meter, just the strips. It's a wide range one at least. I'm getting numbers in the low to mid 4's.

That's quite unlikely. Wells in mesic regions tend to test in the high 5's to low 6's. Test strips are pretty worthless.

So I bought that PH stabilizer that suppose to put it at or just above five. My confusion is should the mash be 5 ish or the water right out of the tap? I put this stuff in my water out of the tap and it doesn't seem to budge the numbers.

That product is supposed to buffer mash to pH 5.2 - not water. It buffers water to around 6. This is further evidence that the pH strips you are using are worthless.

 

[MindenMan]

The pH strips on the plastic type backing are better than the ones on a paper backing. The 5.2 product is up for discussion, some people swear by it, some people say it is bunk.

 

[ajdelange]

The 5.2 product has been pretty thoroughly discussed with a lot of people including the guy who formulated it and all agree that it does not do what the label says it does. So this becomes another opportunity to launch the comment that it works for people who do not own pH meters but does not work for those who do.

 

[W0rthog]

Thank you for your time and feedback.

 

[TrickyDick]

Since the topic of pH meters came up, any endorsements on specific brand/model for homebrewers?

 

[ajdelange]

See https://www.homebrewtalk.com/f128/ph-meter-calibration-302256/

 

[beentheredrankthat]

Given that this is the brewing science forum it should probably be mentioned that at very low mash and subsequent lower beer pH the reactions that form Trans-2-Nonenal (papery, cardboard taste in beer) from malt derived lipids are favored. Probably not an issue if you are not storing your beer for long periods.

 

[KeninMN]

Has there been any research on the effects of pH on conversion efficiency?