This document discusses the process of making espresso coffee. It begins with an introduction to espresso coffee consumption and caffeine content. The main concepts covered include percolation, which is the extraction of coffee solids and flavors from ground coffee beans using hot water under pressure. The key parameters for percolation in an espresso machine are water temperature of 90 degrees Celsius, an inlet pressure of 9 atmospheres, and a percolation time of 30 seconds. In conclusion, making a good espresso requires understanding percolation as the essential extraction stage.

1. C FFEE
EXTRACTI N

2. WHAT AM I GOING TO
TALK ABOUT?
BASIC
CONCEPTS
PERCOLATION.
THE ESPRESSO
MACHINE
WHAT
HAVE WE
LEARNT?
INTRODUCTION

3. ESPRESSO
COFFEE
o Capacity just over 50
mL
o More than
50.000.000 cups/day
are consumed in the
world
o It contains less
caffeine than the more

4. Percolation
SOLVENT RAFFINATE EXTRACT
SOLIDS
WATER COFFEE
(COFFEE GROUNDS)
EXTRACTION
SOLID
COFFEE
BEANS

6. PARAMETERS
o Water temperature: 90 ºC
o Inlet pressure: 9 atm

7. PARAMETERS
o Percolation time: 30 s

8. WHAT HAVE WE LEARNT?
 It is not that simple to make a
good espresso
 Percolation is the essential
stage

9. QUESTION
S