It is one thing having raw coffee, it now needs to be roasted, blended and then converted into a great cup of coffee. In their raw form, coffee beans are relatively odourless, tasteless and indigestible. The roasting process draws out and develops the vast array of aromas and flavour characteristics of coffee as we know it. The same bean can take on different characteristics depending on style and degree of roast. Depending on the degree of roast and the type of roasting equipment, roasting can take anything from 5–22 minutes. It is the same skill and art of the roaster which is vital in understanding how best to roast any particular bean variety or blend.
There are a number of different degrees of roasting, the most common being:
Light – which gives a mild taste, popular in the USA
Medium – for a medium stronger well–rounded flavour
Full – produces a rich, full–bodied, well developed aroma and flavour
High – adds a strong roasty and bitter flavour, favoured by the French and Brazilians
Most well known brands are made from a combination (or blend) of coffees which come from different countries of origin and may contain different degrees of roast. These commercial blends are formulated to produce a consistent taste and aroma.
The purpose of blending is to combine a variety of coffee flavour profiles (i.e. the aromatics of one coffee with the acidity of other and the body of another coffee). For example, a Colombian coffee with high acidity may be combined with a Brazilian coffee with heavier body and no acidity. This will balance the flavour retaining a good body.