Bru'n Water pH Rounding

[oujens]

Martin or anybody else with the answer - what is the rounding used for the Bru'n Water mash pH estimate? I assume to the nearest tenth? My meter accuracy is +/-.02 so I just want to be sure how to interpret the estimate. I recently discovered that my estimates have been off for some beers using a different calculator so I'm making the switch. I'm using RO water, salts and lactic acid to hit mash pH.

thanks

 

[ajdelange]

Be aware that each of the spreadsheets will give you a different answer based on different models of differing robustness. There is a robust model (or pretty robust anyway) that no-one uses for various reasons including it's creator in which case it's because the data isn't available to put into it. So don't expect answers with rms accuracies of ±0.01 or 0.02.

If you find one calculator gives you better answers (compared to your meter readings) than another then that one models your malts and methods better than the others. Stick with it but still be prepared for the occasional surprise. Rely on the meter.

 

[oujens]

Thanks for the response. I typically brew paler beers. I found my ph estimates are off when fewer salts are added. I guess I could take a pH reading and adjust accordingly, but I would rather be as close as possible to the target. I'm not comfortable with adjustments "on the fly" just yet. I'm assuming adjustments would need to be made fairly quickly to have an impact? So if I take a reading 15 minutes in it would probably be too late?

 

[ajdelange]

Yes, there are definitely problems with 'on the fly' adjustments. The best way around this is to use a spreadsheet or calculator to get into the ballpark, to prepare a test mash (about a pound of grist and a something over a quart of mash temp water) and check its pH. On the fly adjustments can then be made the test mash. Those adjustments applied to the full length brew should get you pretty close but you will still want to measure the actual mash and then make small adjustments in future brews of the same beer. Eventually you will converge.