Interested in doing a gose and would prefer to use lactic acid over malt. From what I hear it’s a good idea to shoot for a ph of 3.8 after conversion. Is that true? Is there a simple conversion for acid malt to lactic acid?
Acidulated malt is ~2% lactic acid by weight, and 88% lactic acid has a density of 1.21 g/mL, so for every pound of acid malt you’d be adding 8.5 mL of acid. Obviously that changes substantially if your maltster uses a different ratio of acid.
Thank you for this.
Can anyone comment on the pH level I should shoot for going into the kettle when attempting a Gose?
The problem is that, contrary to popular belief, Sauermalz (Acid Malt) doesn’t behave or have the same characteristics as Lactic Acid.
In fact, AFAIK, Sauermalz is actually treated with Sauergut (Biological Acid), which also can’t be modeled as xx% Lactic Acid.
A Quote from A.J. deLange:
“The fit was done over the region pH 4.6 to 6 and, as the graph shows, the match is perfect at about 5.45. In other words, 31.3 grams of lactic acid are equivalent in acidity to 1 kG of Weyermann’s Sauermalz at pH 5.45. At any other pH this equivalent does not hold. Thus at pH 5.45 Weyermann’s Sauermalz has an effective lactic acid content of 3.13%.”
I have used a lacto starter with pretty good results - dropped pH to 3.5 in 14 hours. I covered and sealed the kettle with a CO2 blanket to keep the nasties at bay, then boiled for 15 minutes to kill it all off then chill and pitch tha Sacc.
In my experience, 3.5 is barely acceptable in a sour. But less than 3.2 is too much for most drinkers. Somewhere in that range is what I target.