Mash PH Questions

[Paws Xa]

Starting this as a general discussion on mash PH for the more experienced brewers to help out the newbies (Like me) to understand the finer points of checking and adjusting mash PH to improve their beers.

So to start off.

I have bought one of the cheap yellow PH meters off trademe to start checking my mash PH an improve my process. I brewed a simple SMaSH brew today with Gladfields Pilsner malt.

I tested the mash at mash temp (67 degrees C) and had a result of 5.5. I then cooled a sample to room temp (about 23 degrees) and the meter said 6.1. This is a massive difference in PH and 6.1 is a long way from ideal.

My meter does not come with Automatic temperature correction (ATC) so what was my actual mash PH?

And what do I need to do to get an accurate reading of mash PH?I really want to get this right before I start adjusting my mash PH

All help appreciated.

[James Guilford]

Where can I get a water report from for my local area? Im in Napier and the council does not have much online.

My Pale Ales are suffering with some astringency which Im guessing is a mash pH issue.  

[Harry]

http://hbrc.govt.nz/Services/Environmental-Sciences/Water/Pages/Gro...

[Cain Harland]

Thanks Harry. Gret info now i just need to figure out how to make sense of it

[James Guilford]

Thanks Harry. I was looking in the wrong place. Regional Council not City Council. 

[Harry]

if you go back a few weeks there is a thread on hawkes bay water.

Im jealous about that website though, council over here are not nearly as useful.

[Cain Harland]

I think I'm having the same issue just a slight astringency that doesn't ruin the beer but I would be happy to lose it.

I have been using gladfields PA base malt and according to their web site:

"Our malts have a typically high pH, a congress mash of this reflects the combination of all the other factors we take into account when malting. This is something of a balance we look at as maltsters, in order to lower this pH we would inadvertently affect other quality factors of our malt. Things like fermentability, Kolbach Index extract and flavour.
Remember that you can easily adjust your pH with use of our Sour Grapes Malt (1% Sour Grapes lowers 0.1 pH), but a lack of flavour or extract are much more difficult to make up for.
Measuring the Mash pH is really important to keep the Yeast happy!"

So I'm starting to add a little acidulated malt to my mash.