Coffee should not be kept hot on the hotplate of coffee machines or on a warmer. The reason: the
heat will cause the coffee to re-draw. This means that water will evaporate, resulting in the
evaporation of the fine coffee aroma. Coffee will not only lose its flavour; it will also taste bitter very
quickly.
Coffee bought at the small roasteries found in almost any larger town is freshest. These roasteries
generally sell high-quality beans which are roasted gently for a long time.
Espresso and coffee are made from the same bean but the roasting times are different. Espresso is
roasted for longer than coffee. The result: espresso is tastier and has a stronger coffee flavour with a
lower acid content. Classic espresso generally comprises a mixture of Arabica and Robusta beans.
However, what distinguishes espresso and coffee most is the way they are made. Espresso is not
made in filter paper; it is made in a metal sieve. Within 10 to 12 seconds for automatic coffee
machines and within 25 to 35 seconds for espresso machines used on a cooker hotplate, water
heated up to 95°C is forced through this sieve. This means that the espresso powder only makes brief
contact with the hot water. All of the flavouring but only a little caffeine and few bitter substances
are dissolved in the powder. This is why an espresso, which is considered to be a black, particularly
strong beverage, only has half as much caffeine as a cup of coffee.
Training manual Section 7 – Page 9
Coffee machines