5

  1. What produces more crema when extracting espresso, darker or lighter roast?

  2. What produces more crema when extracting espresso, finer or coarser coffee grind ?

  3. why am I getting a very thin layer of crema when pulling a SINGLE shot, although the extraction time is 20 sec, the pressure is correct as per the manufacturer of the espresso machine (Breville Barista) I have, and the coffee beans were roasted two weeks ago?! what is wrong?

Edoardo
  • 158
  • 13
Anis
  • 71
  • 1
  • 3
  • I feel like these questions have been asked a bunch of times before. https://coffee.stackexchange.com/questions/2867/what-factors-influence-crema-production-in-espresso https://coffee.stackexchange.com/questions/9/what-factors-affect-espresso-crema – avocado1 Oct 01 '18 at 09:17
  • Have you tried some robusta beans? – Edoardo Oct 05 '18 at 10:42

1 Answers1

3

The CO2 stuck within coffee grounds produce the crema. At least, it is the main substance that forms the crema along with other minor components.

This is a very classic problem -and thus a question.

  • If you consider roasting, darker roasts have more crema as they contain more CO2 as the product of Maillard reaction. Here is a proposed previous post to be read. You may also want to check this previous post as it may lead to more reading on other metrics you may consider.

  • Grind has some effect, but limited. You may see the factors that effect crema production in espresso in this proposed previous post to be read.

  • As you have mentioned, time has a crucial importance. I think this should be your main consideration and you should focus on fixing this first. Basically, fresh coffee has more crema, always. You can read a lot more in this previous post.

MTSan
  • 7,738
  • 2
  • 21
  • 47