Light, Medium or Dark Roast? What Does It Actually Mean?

roast process

Look at a shelf of coffee bags and you'll probably find some labelled light roast, some medium roast and others dark roast.

It sounds straightforward. Three categories, three different colours, job done.

Except coffee has a habit of making simple things complicated.

There is no single universal line separating every light roast from every medium roast. Different roasters use different approaches, and a colour alone doesn't tell you everything about how a coffee will taste.

But roast level is still a useful place to start.

What happens during roasting?

Green coffee beans don't look or smell much like the coffee you're used to drinking.

Roasting transforms them. Heat drives off moisture, develops aromas and changes the chemical structure of the beans.

As roasting progresses, the flavours that were already present in the coffee interact with the flavours created by roasting.

The balance changes.

That's why two coffees roasted differently can taste remarkably different, even if they started as the same green coffee.

Light roast

Light roasts generally retain more of the character associated with the coffee's origin.

Depending on the coffee, you might find floral aromas, citrus, berries or a lively acidity.

These coffees can be particularly enjoyable as filter coffee, where you can explore the flavours without too much interference from milk.

They can also work beautifully as espresso. They may simply need a little more attention when you're dialling them in.

Medium roast

Medium roasts sit somewhere between the bright character of lighter roasts and the deeper flavours that develop with more roasting.

Chocolate, nuts, caramel and balanced fruit notes are common descriptions, although the original coffee still matters enormously.

This can be a very versatile starting point if you enjoy both espresso and filter coffee.

Dark roast

As roasting continues, roast-developed flavours become more prominent.

Think deeper chocolate, toasted nuts and, with darker roasting, more smoky or bitter notes.

The original character of the coffee can become less obvious as the roast becomes more dominant.

Some people love this style. Others prefer something lighter.

Neither group is wrong.

Which roast should you buy?

Start with the way you enjoy drinking coffee.

If you like exploring different flavours, try a lighter roast. If you prefer chocolatey espresso or coffee with milk, a medium roast may be a good starting point. If you enjoy a more pronounced roasted flavour, explore darker options.

These are suggestions, not rules.

And remember: dark roast doesn't automatically mean strong coffee, just as light roast doesn't automatically mean weak coffee.

Read next: What Is Specialty Coffee? to understand what makes a coffee special beyond its roast colour.

— Henning  Al-Gharb Coffee Roasters, Algarve

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