Understanding the roasting process

When you roast, you are heating the beans in order to create a number of key chemical and physical changes to the coffee bean. The moisture or water in the green bean boils off, the bean's starch transforms into sugar, and the sugar caramelizes to create a sweet, flavorful coffee.

Roasting is smoky. All coffee roasters make smoke. Roast outside, in the garage, in any well-ventilated space or by a stove hood fan.

In addition to being accurate with the amount of coffee you use in each roast, you need to set the timer carefully. Experiment with a few roasts. Always watch the beans closely, especially after 4 minutes. When they start to pop and crackle - it's getting close.

When the green coffee beans roast, they turn light brown, then yellow, and eventually tan as they begin to "pop." This is a chemical reaction known as pyrolosis.

The coffee beans pop because the beans are expanding, roughly doubling in size. The bean's proteins slowly change, becoming the coffee oil that comes to the surface.

(There are about 600 different volatile oils in coffee that give coffee its characteristic aroma and flavor.)

In a few more minutes, the second "pop" occurs, this time as the bean's cellular structure is breaking down. In rapid fashion the beans become dark and oily. The smoke from the roaster increases, as does the bean's smoky flavor, as the coffee sugars can quickly burn!

A deep, dark roast can be tasty, but it needs a sturdy hard grown bean with cellular density that can take the heat. A weaker bean often tastes burnt and then you'll need to add milk and/or artificial flavors to make it drinkable.

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A general description of various roast levels related to taste

A City Roast results in a coffee that is more crisp, and acidic - like a bright wine. The specific features of the variety of coffee will be most prominent. These are flavors that many people have never experienced in coffee and can include fruity notes and chocolate tastes that occur naturally in different coffees. This is the style generally preferred in most of eastern America, and Northern Europe, and quite suitable for drip coffee, especially when drank with milk.

As the roast darkens, the acidity gradually lessens, while the body of the coffee becomes heavier. With Full City Roast, then Viennese Roast, the coffee also gets increasingly sweeter. The original varietal characteristics of the coffee beans get somewhat less pronounced, and the coffee becomes more pungent, and spicy in flavor. As you get into a French Roast the bean surface becomes shiny, the coffee will obtain a very heavy body, and a distinctly bittersweet taste.

As a general rule, to obtain a brighter, light cup with more varietal flavors, try a lighter roast. This is best suitable for drip coffee. To get less acidity and a heavier bodied coffee, use a darker roast, which is usually more enjoyable for vacuum brewing or espresso.

What roast level is best? You decide! A lot depends on the variety or blend of the coffee, how it will be brewed (drip, press pot, espresso machine, etc.), and your own personal tastes.

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