Effect of boiling on pH of kettle soured Berlinner Weiss

[torque2]

I'm attempting my first kettle sour Berliner Weisse using WLP 677. After 4 days my pH is sitting at 3.88. I'm looking for a final pH of 3.5 - 3.6. I'm planning on a 90 min. boil which should bring my volume from 15 gal. down to 12.0. Does anyone know how this will affect the pH? I'm assuming that since lactic acid has a higher boiling point than water that the pH will go down, but I don't know how much. Any experience with this?
Thanks,
Tim

 

[torque2]

After further research I'm not going to even boil it, just bring it up to 170 for 10 min w/ 5 ibus of Saaz and call it good. The twang will be mild, but should please a bigger crowd. I'm planning on adding apricot puree to half (post- ferment) and WLP 670 to the other (pre-fermentation).