So I make my Berliners using the sour wort method. I collect my wort in a corny keg and drop 8 oz of unmilled US 2-row in the keg. I then put the keg in my fermentation chamber set at 110 degrees Fahrenheit for optimal lactobacillus growth. It usually gets the pH down to 3.2-3.3 in about 27 hours. Then proceed to boil. I've done this method about 5 times and it turns out great every time. But this time my pH has not dropped at all. So was something wrong with my grains? I'm stumped.
I think it would be hard to find grains that don't have some bacteria on them, but I suspect the amount is pretty variable. Maybe add more grains/more time.
Keep it in the keg at 110F or a little higher, with no O2, and I don't imagine anything would happen, except for lacto activity.
