Calculating to adjust pre boil pH

[aeviaanah]

Want to adjust a future Gose pre boil pH to help lacto get started. Any calculators out there?

 

[yeehaw_charles]

Use Brew'n Water. Set desired pH at 4.7 to give the lacto a nice head start.

 

[aeviaanah]

I currently use brew n water to calculate mash pH. How can you get the spreadsheet to calculate from a measured preboil pH to a desired?

 

[yeehaw_charles]

Just keep increasing lactic acid addition until pH drops to 4.7.

 

[aeviaanah]

I still want to mash around 5.4. Are you saying take the difference to get to 4.7 and add that after the mash?

 

[aeviaanah]

Bump

 

[mabrungard]

Yes, mash around 5.4 to produce the proper enzymatic reactions and then acidify the resulting wort to around 4.5 to help avoid unwanted beer spoilers from taking hold before your lacto culture takes over and drops the pH the rest of the way.

 

[aeviaanah]

But how do I figure the actual lactic acid addition (4.5ph)? Should I just add the acid addition difference from estimated mash pH figured at 5.4 and 4.5?

 

[cactusgarrett]

Interested to know if there are calculators to do this.

In my limited experience with this topic it seems (to me) the two practical approaches are 1) measure with a pH meter as you add lactic acid to the pre-boil, or 2) just add a given amount and hope for the best to get in the ballpark. I did the later with a recent Berliner Weisse (due to my lack of pH meter) and it appears acceptable to me; crazy sour.

I read that given a 'standard' grainbill (mashed around 5.2-5.4) the ballpark amount to add is something like 5-15mL of 88% lactic acid to 6gal pre-boil to bring down to ~4.6 pH.