[jyl]

Espresso folks,

my shots have been sour lately. I’ve tried using better and darker roasted beans and grinding finer, which helps but not enough. I’m doing 21 g coffee into 36 g shot which takes about 35-40 sec. My machine is a heat exchanger type so I can’t change the brew temperature, at least not easily. The only things I can think of are to change my dose or replace my burrs. The grinder is a Mazza Major with about 7,100 shots on the burrs.

Ideas?