Lactic acid

[kabert7]

I found a recipe elsewhere that incorperated lactic acid to give the sour character to their beer. It said to add the acid to the finished beer. I tried adding some 88% lactic acid (about 300uL) to 12 oz of our Irish Stout. It had the desired effect. The question is: Can you acidify the beer before bottling or would the drop in pH inhibit the yeast from converting the priming sugar?

 

[david_42]

Took a bit to find this, but I remembered a lecture by a Wyeast lab tech:

The "tried and true" method of washing yeast utilizes phosphoric acid (H3PO4) to acidify the yeast slurry to around pH 2, where it is held for a given amount of time, ranging from two hours to overnight. In theory, undesirable organisms are destroyed by the low pH and trub is removed from the yeast. The healthy yeast remains suspended and is used for pitching, while dead cells and trub collect at the bottom of the washing vessel.

I don't think a little lactic acid will slow them down.

 

[kabert7]

Thanks for the information. I'll post the success or failure of our lactic acid test.