question about lactic acid and mash ph

[Travisty]

I have nothing to add to this thread other than I love these conversations. I'm a pH whore, too and any topic on i grabs my attention.

And I like the different methods used.

+1

These conversations are brewing gold IMO!

[SacoDeToro]

thanks guys. i just picked up a bottle lactic acid and a glass pipette. i will try the lactic acid first... but i am intrigued by the sourmalz.

julian,
what sort of response time for the ph to change do you experience when using the lactic acid?

do you use a meter or strips to check ph? i only have strips... is this good enough? or should i invest in a meter?

I used a pH meter years ago when I began getting into brewing water treatment/chemistry. I was able to zero-in on a few treatment schemes depending on the type of beer I was brewing. After empirically correlating my predictions and calculations with observed consistent results, I pretty much put the pH meter away. On rare occasion I bust it out, but the results are always where I expect them to be. I never measured how quickly pH shifts occurred. For what it's worth, I add my lactic acid to my mash liquor prior to doughing in.

To add to previous prose, the Weyermann rep said the lactic acid used on their malt was made from a large culture they keep at the maltster. In a similar vein, Jim Crute of Lightning Brewery is a Reinheitsgebot adherent and to my knowledge, maintains a lactic culture in a tank for the purposes of making his own "natural" lactic acid to acidify his mashes.

[larry78cj7]

How much of a factor is mash pH on extraction efficiency?

[ajdelange]

How much of a factor is mash pH on extraction efficiency?

See viewtopic.php?f=2&t=18849

i only have strips... is this good enough? or should i invest in a meter?

IMO strips are not adequate. You are looking for pH differences of 0.05 pH or less. Many of the strips have a precison of 0.3 or 0.2 pH and the most popular ones seem to have a bias on top of that of -0.2 to -0.3 units. Chasing down pH with that kind of performance would be like trying to find an address in Seoul if your GPS receiver had a resolution of a half mile.

So should you buy a meter? If you are going to try to adjust pH or want to see its effects then the answer is "yes". I wouldn't have given that answer a few years back but now reasonably priced (under $100) units with reasonable precision (readable to 0.01 pH) are available. I don't know how long the electrodes last but at that price even if it's only a year that may be tolerable.

There are some potential pitfalls with pH meters too, of course. They need to be calibrated with fresh buffers (i.e. a 2 point calibration though many meters allow single buffer calibration) each day they are used and mash (or kettle) samples should be cooled to room temperature (ideally the same temperature as that of the buffers when the instrument was calibrated).

You will learn a lot about the brewing process if you monitor pH at several points throughout the brewday i.e. at dough in, the end of each rest, after the return of each decoction, going into the kettle, coming out of the kettle and throughout the fermentation. This last one should demonstrate a drop of several tenths of a pH unit within hours of pitching well before any bubbling, kreusen or gas evolution are seen.

If you get to the point Julian mentioned where what the meter tells you is exactly what you expect you can take fewer measurements or skip them altogether with the exception of that one in the fermenter. See that pH drop tonight and tomorrow you will have a healthy fermentation underway.