I rarely use darkly roasted, but I am currently playing around with Lucky Goat's Lucky 7 espresso blend. My problem is that I can not slow it down. They said they do 19g in 38g out in 28s. I have a Breville dual boiler with 10s pre infusion, so I am aiming for 38ish seconds, but I can't come close. Even with my smart grind pro on a burr setting of 1 and a grind setting of 5 or less I can't slow it down. Also, I'm only putting in 16.5-17.5g. One thing that has helped is Matt Perger's tamping technique. Any other advice for a novice home barista?

Don't know the specific blend that you are using, but when was the roast date?

Unfortunately, you've probably exceeded the capabilities of your grinder.

DeGaulle wrote:Don't know the specific blend that you are using, but when was the roast date?

I believe 11/15-18. It's a little old now. For the first time I got my extraction at the target time of 38s. It's on Burr 3 grind size 7, and I do the Matt Perger rolling style tamp( I go around the puck with the tamper twice). Hopefully now that I'm in my target range I can start fine tuning it, but if you have any more advice it would be greatly appreciated!

TomC wrote:Unfortunately, you've probably exceeded the capabilities of your grinder.

I agree completely. Getting a more capable grinder will open up new possibilities in adjusting your extraction. The grinder is more key than the espresso machine.

Dark roasts usually require much coarser grinds, maybe its the age? Try less pre-infusion, long preinfusion requires finer grinding.

It depends. Dark roasts may create more fines (dust). Also they are more soluble than light roasts. This suggests a coarse grind. But if a dark roast is too intense, you'll want to grind it finer and downdose. The Caffe Lusso Gran Miscelo Carmo we reviewed this year worked well with a 1:2 brew ratio and a 25 second pull. I didn't do a coarse grind of that coffee. It had to be sufficiently fine to offer resistance. My lever pulls actually took much longer, but that's because of the declining brew pressure of a lever. I like to brew some dark roasts cooler, also, to reduce bitterness and bring out any remaining acidity. That was not the case with the coffee we reviewed, which was very balanced at the usual brew temperatures.

I always consider preinfusion part of my shot time. As long as there is water in contact with grounds it's extracting the coffee. 38 seconds seems way too long for dark roast shots.

Aim for your 38g out in 28 seconds including preinfusion. Also consider reducing preinfusion time from 10 seconds.