Before we investigate how to make good coffee it helps to look at what is a good cup of coffee? A cup of coffee that makes you happy would be a good place to start.
For today we are going to assume that the beans were picked at the right time the processing, transport, roasting and storage were ideal.
In the 1950s, the National Coffee Association looked to MIT associate professor of food technology, Earl Lockhart, a biochemist by training, to determine what makes a good cup of coffee. His findings in the ’50s still form the basis and fundamentals for consistently brewing a good cup.
As a general guideline, a good cup of coffee (or espresso for that matter) will dissolve 18-22 percent of the ground coffee into the water. Espresso uses pressure and less water to get to a 7.5-9.5% strength or higher while coffee is generally made between 1.15 to 1.5, with stronger brews more common in Europe and outside the US.
Here is a close up of just the coffee section highlighting the differences in the brew strength. The Specialty Coffee Association of America (SCAA) defines a Golden Cup of coffee to be between 18-22% extraction with a strength of 1.15-1.35% dissolved solids. If you dissolve less of the coffee bean into the water, the coffee will most often taste sour and may even taste like drinking vegetable soup. If you go over 22% extraction, the coffee will start to taste bitter and dry and make your mouth pucker.
Here is the same chart with an added “high extraction” zone. With very uniform grind size and a consistent extraction from all of the coffee particles, it is possible to push extraction above 22 to 24-25% or so before making the coffee too bitter. For more information on how to get high extractions check out the resources at the bottom of the page.
Want to find out how to make good coffee now – check out our how to make coffee database and our analysis of over 100 recipes and the common tips and tricks in pour-over coffee and more
- SCAA http://www.scaa.org/chronicle/2013/10/04/the-coffee-brewing-institute/
- Great color brochure on proper coffee brewing by BUNN http://www.bunnomatic.com/sites/default/files/resources/eZine/coffee_basics_scaa/index.html#p=4
- Espresso range of 7.5-9.5% http://www.baristahustle.com/analyzing-espresso-recipes-strength/ and more on coffee tasting http://www.baristahustle.com/coffee-extraction-and-how-to-taste-it/
- Nice piece on optimizing coffee by focusing on the grinder https://www.mpechicago.com/coffee/images/uploads/pdfs/scaa_2010.pdf
High extraction yield:
- A great post on brewing coffee with particles between just 700-800um and extracting to 24% for a great cup https://theotherblackstuff.wordpress.com/2011/02/16/the-dark-age-of-grinding/
- World Champion Barista, Matt Perger on why he extracts over 21% and the importance of a good grinder http://www.baristahustle.com/extract-more-better/