Puck Screen Temperature Drift
Lately I've had my butler steam my puck screens before he brews my espresso. I've noticed that the espresso had a slight tinge of what I would call citrus note, something more along the lines of a lime rather than a sharp lemon, something sweeter like a tangerine, but more of a faint hint of lime.
Assuming that this could be a slight issue with temperature, I asked my butler if he was pre-heating my puck screens, and to my surprise HE WAS NOT, so I instructed him to do so. Being a bit of an engineer, I decided to temperature test the shots on my La Marzocco Linea Mini (matte black with all custom walnut, with the built in scale, plumbed in direct to my whole house BWT filtering system), and I was SHOCKED to see a thermal deviation of .08 degrees, which I'm sure was the culprit of the lime aftertaste I mention eailer. Understanding how the temperature of the basket and group affected the final shot, I couldn't believe such a tiny puck screen could make such a HUGE difference in tase. Not only is the overly sweet lime/tangerine afternote gone, the espresso now has more of an apple sweetness, along the lines of a fresh Gala apple in the fall. It totally changes the entire coffee from a good 88 or 89 point cup into something clearly in the 90+ range.