Photo of the Spirit espresso machine, kindly provided by Kees Van Der Westen.

• We explain how different machines control the water temperature and why some designs are more precise than others.
• We explore how the water temperature and other factors can alter the effective brewing temperature in the puck.
• We discuss the links between brewing temperature and other factors, such as shot time.
• We look at the effects of brewing temperature on extraction and flavour.

End 5.00