Coffee Roasting
Roasting is performed in a large special made roasting machine, which look like an extra large tumble dryer.
The green coffee beans are poured into the roasters cylindrical container which is preheated to an exact temperature.
The beans are then spun around in the cylinder to ensure they are heated evenly.
Through out the process the person roasting keeps a very close eye on the beans by checking their temperature, time, smell, appearance and the sound they make.
The sound and appearance is checked by taking a small sample from the drum by means of a tryer.
Commercial Coffee Roaster
The whole process usually takes between 10-15 minutes dependant on the type of taste require.
- A quicker roast, around 8 minutes, gives a light more acid taste and is referred to as a cinnamon roast
- A medium roast, 9 to 11 minutes, gives a light brown slightly sweeter taste with more balanced acidity and is known as full city.
- A longer roast, 12-14 minutes, give a much darker beam with a sweet chocolaty taste though still holding some of the acidity. This is referred to as a Vienna roast and is highly popular.
- Finally a very long roast, 15+ minutes, give a very dark, almost black bean. The sugars have carbonised giving a smoky intense flavour, though its has now lost the subtle coffee flavour. The is know as a French roast.
Once ready the roaster door is open and the coffee beans tumble onto a cooling tray below.
The beans are spread evenly over a screen which has small holes allowing air to be drawn over then beans helping to cool them.
When the coffee beans have cooled they are ready to be packaged for sale or made into a cup of coffee.