too low wort pH

[D-urb]

So, I have been trying to figure out an efficiency problem and have a question about pH. My local water pH is around 9.5 and when I checked my pH with an electric meter I bought, it was 4.2 in the mash. Would this lead to my efficiency problem? Would longer mash time fix this? Or, should I add bicarbonate?

 

[craigmw]

So, I have been trying to figure out an efficiency problem and have a question about pH. My local water pH is around 9.5 and when I checked my pH with an electric meter I bought, it was 4.2 in the mash. Would this lead to my efficiency problem? Would longer mash time fix this? Or, should I add bicarbonate?

You need to figure out what your water parameters are, and should be able to get these from your local water utility. Then, use Brewer's Friend or Bru'nWater to determine your needed additions. Did your grain bill have lots of crystal or darker malts? These will reduce the pH, and you can control for this using lime or bicarbonate. However, it would be best to estimate how much adjustment would be needed based on the grain bill and your water parameters (e.g. total alkalinity, total calcium, etc). Incidentally, if your mash pH was truly that low, that could indeed impair diastatic activity during the mash. Optimal mash pH is around 5.3 as a compromise for alpha and beta activity.

 

[ja09]

First off, how did you take your sample, which ph meter do you use, and was it properly calibrated the same day before use? That's really far to be off unless you have something seriously wrong with your water, recipe or process. What's your water source and what's the recipe?

 

[mabrungard]

4.2 is really hard to believe if that measurement was performed on a room-temperature sample with a calibrated pH meter. It would take quite a bit of screw-ups to get the pH that low. I've produced a mash pH as low as 4.9, but that was also a fairly untypical case.

You do need to find out what your water quality is before thinking about treatment options.

 

[D-urb]

Thanks for the feedback. I think I know what I did now. It was simple PA that shouldn't bee too acidic. I've looked at our water and it should be good for most beers except pilsners. I actually took the sample while in the mash tun. I forgot that it needed to be at room temperature. I used an electronic meter that was calibrated correctly. I just dipped it into the mash to check it. I remember now reading that it had to be at room temperature but forgot about that when I did my last brew. Do you guys just pour off some wort and cool it, then check it? I didn't think I should be low based on our water profile.

My efficiency last brew was actually good. I've pretty much got what was going on figured out and the pH was the last thing I was checking. I've never checked before and never had problems but the process of figuring out my problem made me want to check...just did it incorrectly.