One of the most important factors in determining the taste of coffee is the degree to which the coffee beans are roasted, which is called its roast profile. The process of coffee roasting starts with raw, green beans that have little to no taste. It transforms them into aromatic and flavourful crunchy coffee beans.
The most common way to determine the roast level of a coffee is by the colour of the roasted beans, ranging from light to extra dark. As coffee beans absorb heat in the roasting process, their colour becomes darker and oils appear on the surface of the beans at higher temperatures. Once the coffees have dried out from around 12% moisture down to less than 4%, interesting things start happening. First the acids in the coffee begin to develop and as it gets darker the sugars will develop. The acids then begin to be consumed, with some turning into new sugars. Eventually the sugars begin to caramelise and crisp (known as Maillard reaction, as found in browned toast) and finally, the fibres will begin to burn.
Preferred roasting profiles can vary depending on where you are in the world. Europeans have traditionally favoured dark roasts, which is why a coffee roast may be described as French, Italian or Spanish, as these are particularly dark. Also, in the United States, those on the West Coast tend to prefer darker roasts than those on the East Coast.
The roast profiles of coffee that we provide here at Redber are medium, medium-dark, and dark. Here is a little more about each one:
Medium roasted coffees are medium brown in colour and have no oil on the surfaces, with a balance of flavour, aroma and acidity.
Try our Ethiopian Sidamo in Medium.
Medium-dark roasts have a richer/darker colour with some oil beginning to show on the surface of the beans. A medium-dark roast has a heavier body in comparison to the medium roast. The flavours and aromas of the roasting process become noticeable, and the taste of the coffee may be somewhat spicy.
Try our Uganda Bukonzo in Medium-Dark.
Dark roasted beans are dark in colour, like chocolate, and may sometimes be almost black. They will have a sheen of oil on the surface, which is usually evident in the cup when the coffee is brewed. Dark roast coffees will generally have a more bitter and smoky taste. Also, the amount of caffeine is substantially decreased.
Try our Guatemala Huehuetenango in Dark.
A few things to note…
- The coffee beans take on more flavour from the roasting process, and lose more of their origin flavours as they get darker.
- Medium roasts have more acidity than darker roasts.
- Darker roasts develop oil on the bean surface.
- The caffeine level decreases as the roast gets darker.
- The weight per coffee bean decreases, and the coffee beans get bigger as the roast gets darker.