"Espresso! My Espresso!"
An Ongoing Internet Novelette
by Randy Glass - Copyright 2002 - All rights reserved
E-mail me at firstname.lastname@example.org
Always Room For Improvement
After nearly two weeks or more of excellent espresso I thought I would share my findings. In the past I have always suggested, particularly to newish, home barristas ("That's funny... you don't LOOK newish!"), as well as those who have lost the handle on consistency, to tamp hard- around forty to fifty pounds of force, and grind accordingly to dial in the 25-30 second, one and one half to two ounce double. The reason this works is that the hard tamp is very repeatable because after about 35 pounds of force, the coffee compresses very little if at all- at least not enough to change the shot. The difference between a twenty pound tamp and a twenty-five pound tamp can be dramatic, but there is little difference between a thirty and a forty pound tamp.
As in all arts, you don't get something for nothing. The heavier tamp necessitates a coarser grind, and a coarser grind does not allow as full of an extraction. It only makes sense. The particles are larger so there is less surface area of coffee exposed to the water in proportion to the volume of the coffee. There is also the matter of larger particles leave more space between themselves for the water to flow, and that is why you need a harder tamp with a coarser grind.
Anyway, I have had some really great espresso at my roaster friend's shop from his Giotto. I noticed that his grind was noticeably finer than what I have been using and he also used a much lighter tamp than I have been. I took some of his blend (roasted by him as well) and went home and experimented. Some test pulls and taste tests led me to a finer grind and lighter tamp. What this has brought me is about two weeks of daily great espresso with only one pull discarded and that was from a poorly seated portafilter that allowed clear water to leak into the cup. The pulls stay dark longer and even at the end of the pull are still rich in color- more dark caramel colored at the end whereas before the pulls got light about the last five seconds or so. The crema is dark and the smell of the espresso is deep and rich with far less bitter overtone that I would often receive before.
Now the problem is, how to tamp with less force, consistently, and without the bathroom scale in the kitchen or the espresso machine in the bathroom. It is a matter of feel, and it's difficult. With only a couple of weeks or so of practice, I cannot state that I have got the feel for it, but it goes something like this. It is around a 20-30 pound tamp (again, I have not measured it to know for sure). The usual procedure is followed (light tamp, tap tap, heavy tamp). The heavy tamp is done slowly until the coffee reaches the point where the tamp goes from fluffy to firm. I will try to get out the bathroom scale and quantify it in a future chapter, once my "new" procedure settles in.
For now, I will say to you- grind finer, tamp lighter, and sip happily.