Kettle Sour Question - Top off after souring, before boiling?

[TAK]

I did a "kettle" sour where I soured in a temp controlled keg before transferring back to a kettle for boiling. The thing is though, I can only get 5 gal out of the souring keg before boiling. Then after boiling, I loose about a gallon.

Is there any issue with topping off with a gallon of water after kettle souring before boiling, to account for the expected boil off?

Is it reasonable to assume the pH would remain about the same, not diluted, since I'll be adding the same amount that will get boiled off?

 

[BryceL]

I'm actually wondering the same thing. I'm souring about 7.75 gallons of wort in my 8 gallon kettle and will be transferring it to my larger boil kettle in a couple days. My target preboil volume is 8.5 gallons. Not sure if I should just roll with the 7.75 gallons and come up a little short, or top off with water...

 

[youreanimpulse]

I say go for it. Imagine you lautered more originally then soured. Theoretically sugars would be diluted slightly and souring would proceed the same way. Then you'd boil off the extra water. In my mind it's not different.