Original recipe was 80% pils, 8% munich light, 8% white wheat, 4% carahell but had to use what I had available.

Density of 85% phosphoric acid = 1.685-1.689 g/ml

(grain 30.262 change in pH) / 14.75 = ml 85% phosphoric acid to change boil pH

Adjusting

Swapped out 1 lb Vienna for 1 lb White Wheat.

Was trying to remember why some may mash/boil higher and lower pH at end of boil. Alpha Amalase is more active closer to 5.6 and DMS is boiled off easier at high pH. Lower pH is desired in boil for protein coagulation.

Kai: https://www.homebrewtalk.com/forum/attachments/1437746446595-jpg.292063/

"There is no uniform method for how the pH is used during the process.
The Bavarian method is to mash relatively high with a pH around 5.5 and keep it at that value in the boil until break formation. Then brewmaster treat it differently as well. Some adjust to 5.2 immediately after the break to encourage an even brighter end product, some do it 10-15 minutes before the end.
In Germany there is a trend of mashing much lower, some as low as 5.2, with a minimal dose in the boil.
These all are a matter of preference and style.
In the end they all end up with wort at 5.1-5.2 hitting the fermenter and all use Sauergut. It is "de rigeur""
http://forum.germanbrewing.net/viewtopic.php?f=46&t=207&start=10

"Regardless of style or maltster, the same principle applies:
As the pH increases, protein excretion improves and hop utilisation increases. That's why one is interested in conducting the boil at a pH of 5.4-5.7, seldom outside that range.
Towards the end of the boil the pH naturally has dropped a little and we now lower the pH into the pH 5.2-5.1 range to aid focculation of the proteins, improve taste, colour and biological stability. Usually this is done 10 minutes towards the end of the boil. That's how you get the egg soup effect.
It's quite straightforward"
http://forum.germanbrewing.net/viewtopic.php?f=49&t=174&start=10

"That is not necessarily the main reason for performing a late- or post-boil pH adjustment. DMS removal is aided by boiling at higher pH. My research indicates that German brewers tend to target a modest kettle pH of around 5.4 and dose with saurergut late in their boil to bring the wort pH down several more tenths to suit the yeast and the resulting beer flavor."
http://www.milkthefunk.com/wiki/Dimethyl_Sulfide ctrl+f pH

So boil @ higher pH to reduce DMS, lower pH to ~5.0-5.2 in last 10 minutes for yeast and protein coagulation.

Calculation for adjusting boil pH:
Grain Weight34.25∆pH/11 = ml 88% lactic acid to adjust wort
10.5lb, 5.4->5.2
10.534.25(0.2/11) = 6.5386 ml

Random german brewing ppt: http://www.ahaconference.org/wp-content/uploads/presentations/2008/SteveHolle_GermanBrewing.pdf

Sauergut method: http://forum.germanbrewing.net/viewtopic.php?f=46&t=537&start=10#p8186

Sauergut: https://discussions.probrewer.com/showthread.php?6245-lactic-acid&s=88f328aba6b321ab6b5122872f8447bf&p=15668#post15668