Essentials of good espresso

To produce a single espresso you need:

• fresh, good quality coffee
• water temperature ~90-95C
• 7gm coffee (fine espresso grind)
• ~20 seconds extraction time
• producing 30ml of espresso

All of these points can be achieved by using a well maintained modern machine and having well trained operators.

The last two items are the most common problems. Thirty millilitres of espesso doesn't look like much, but any more water going through the coffee will only produce a bitter, "over extracted" taste.

Coffee shop owners: treat this as a checklist and make sure your machine and operators adhere to it.