The only way to really understand roast is to associate flavor with the color and appearance of the bean rather than with name alone, but for reference I have condensed most of what an aficionado needs to know about the names of roasts in the following roast table.
|Roast color||Bean surface||Agtron Numbers||Common names||Notes|
|Light brown||Dry||80 – 70|| Light|
|Can taste sour and grainy. Typically used only for inexpensive commercial blends.|
|Medium brown||Dry||70 – 50|| Medium|
traditional American norm. Flavor is fully developed; acidity is bright; characteristics of green coffee are clear.
|Medium-dark brown||Dry to tiny droplets or patches of oil||50 – 40|| Viennese|
normal or regular roast for the West and for many newer specialty roasters. Acidity and the characteristics of the green coffee begin to mute. Bittersweetness emerges. The norm for northern-Italian style espresso.
|Dark brown||Shiny surface||40-35|| French|
normal or regular roast for many roasters in the West and Southwest. Acidity
is nearly gone; the characteristics of the green coffee muted. Bittersweet tones dominate. The norm for most American-style espresso.
|Very dark brown||Very shiny surface||35-30|| Italian|
normal or regular roast for Peet’s Coffee and its imitators. Acidity is gone.
In tactful versions of this roast some characteristics of the green coffee
survive; in aggressive versions all coffees taste the same: bittersweet with hints of burned or charred tones.
|Black-brown||Shiny surface||30-25|| Dark French|
differentiating characteristics of the green coffee are gone; burned or charred notes dominate. Body is thin. Flavor is reduced to faint sweet tones.