Roast levels, a discussion of what they mean with Director of Coffee Jeremy Behne

When you walk into one of our coffeehouses you'll find we always have a dark and light roast brewing, ready for your cup. And if you look at our retail bags you'll find terms like Vienna, French and Italian. But what does all of this mean?
Jeremy Behne: Let’s start with the basics, with roasting in general. Coffee is roasted in a roaster for a certain period of time to be brought from room temperature up to as much as a little above 480°. During that time beans go through a first, and maybe, a second crack.

A crack? JB: It’s called crack because there is a cracking noise, like popcorn or roasting nuts in the oven. It’s fairly loud. The first is when moisture expands out of the bean. Immediately after this first crack is the first acceptable point at which you could start drinking the coffee; that is the point where it is considered cooked. Then we roast for an additional small period of time and have the second crack, usually around 440°. This is when the CO2 bursts out. It is a less loud sound but still noticeable. This is when oils, with different degrees of speed, move out of the bean and begin to coat the bean. Most light coffees are pulled before the second crack and dark coffees are roasted past the second crack. And that’s the difference between light and dark.

Light and dark are broken down by two flavor profiles: Light - produces a more citrus, acid note, primarily sweet, with simple sugars. The high acid content does not mean it is more acidic. The coffee notes are sweet, floral. Dark - produces a caramelization of the sugars. The simple sugars turn into complex sugars and you taste more of the roasting notes vs the natural characteristic of coffee.

So now, on to Vienna, Italian and more: JB: To break that down further here at Coffee By Design we have five major categories. The first two I'm talking about are light: Coffee By Design roast - this is the lightest roast that we think makes a good cup of coffee - we used to call it peak roast. This coffee is roasted just to the point where there is an enjoyable contrast between fruit notes and sugars caramelizing. Vienna -- this is slightly darker, focused on caramelized sugars but not roasted beyond the second crack. Acid and floral notes still remain, similar to in the Coffee By Design roast.
And these three are dark: Espresso -- an extended version of Vienna, the coffee is roasted longer to build body, break down acids, develop complex sugars. We take it right up to the second crack and pull it at the very beginning of the second crack. It is not allowed to complete the second crack. It is a slow roast to develop more body and sugars. Italian -- this is our dry dark roast. It will develop oil over time but when it comes out it is not oily. It has strong caramelized sugars, hints of original fruit notes, it is not sour or vibrantly fruity. The marker we shoot for with Italian roasts is a full, rolling second crack.
As such, all of our Italian Roasts are dropped during second crack. It is characteristically a dark roast without a lot of oil. French -- the darkest roast, it has an even distribution of oils across the beans before it is pulled. This roast goes a bit longer past the second crack. It has notes of dark chocolate and bittersweet cacao. The coffee is more brittle and has strong characteristics. The beans are also lighter at this point, weighing less than the lighter roasted coffees.

How does it affect home brewing? If you usually brew dark coffee at home you’ll want to make your grind finer or increase the water temperature for a light roast. Otherwise your light roast coffee will come out weaker. Light beans are more dense. If this is the first time with a dark roast, use cooler water, a shorter brew time and a rougher grind.