So I don't know enough about chemistry to know if this is valid or not.
I'm trying to estimate the percentage of lactic acid in my Sauergut so that I can dose my beer accordingly, but I'm really lazy and don't want to buy a titration kit to measure it properly.
So I plugged my Sauergut recipe and volumes into Bru'nwater and I measured the pH with a calibrated meter at the end of the minimash and immediately after adding 1mL of 88%lactic acid to drop the pH for the lactobacillus. I measured a pH of 4.9.
Today I took a second pH reading of 3.2 immediately before brewing.
So I plugged all my numbers back into Bru'nwater including 1mL of 88% lactic, and then used guess and check to see how many ml of 100% lactic acid it would take to reach a pH of 3.2
It estimated 3.2mL (interesting coincidence) and a have 2500mL of total Sauergut, so that puts me at approximately 0.13% lactic acid by volume.
That seems low but I then plugged my helles recipe into Bru'nwater and used a mixture of 1L of 0.13% lactic acid and 3mL 88% lactic acid to target a pH of 5.4.
I just measured the mash pH and it's 5.2 indicating that the acid % estimate of the Sauergut was indeed a little low.
So did I get lucky? Or is this a valid method for creating a gross estimate of Sauergut acid content without titration?
I'm trying to estimate the percentage of lactic acid in my Sauergut so that I can dose my beer accordingly, but I'm really lazy and don't want to buy a titration kit to measure it properly.
So I plugged my Sauergut recipe and volumes into Bru'nwater and I measured the pH with a calibrated meter at the end of the minimash and immediately after adding 1mL of 88%lactic acid to drop the pH for the lactobacillus. I measured a pH of 4.9.
Today I took a second pH reading of 3.2 immediately before brewing.
So I plugged all my numbers back into Bru'nwater including 1mL of 88% lactic, and then used guess and check to see how many ml of 100% lactic acid it would take to reach a pH of 3.2
It estimated 3.2mL (interesting coincidence) and a have 2500mL of total Sauergut, so that puts me at approximately 0.13% lactic acid by volume.
That seems low but I then plugged my helles recipe into Bru'nwater and used a mixture of 1L of 0.13% lactic acid and 3mL 88% lactic acid to target a pH of 5.4.
I just measured the mash pH and it's 5.2 indicating that the acid % estimate of the Sauergut was indeed a little low.
So did I get lucky? Or is this a valid method for creating a gross estimate of Sauergut acid content without titration?
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