This study investigated the impact of degree of roasting, grinding, and brewing on the evolution of coffee
aroma in green coffee beans from Ethiopia, Hawaii, and El Salvador. Using a highly-trained descriptive
panel, 15 aromatic sensory attributes were identified and quantified in green beans, roasted beans (light,
medium, and dark), ground coffee, and brewed coffee. Analysis of variance (ANOVA) and principal
components analysis (PCA) were done separately for each preparation stage/step. The ANOVA showed
that green beans had low coffee-related characteristics and were high in beany, green, musty/earthy, and
sour aromatics, all of which carried through to the final brews. In general, the light roast was perceived to
be sweeter in all stages and the darker roasts attained higher intensity of the typical ‘coffee’ attributes
with which coffee consumers might like (coffee, roasted, burnt/acrid, and ashy/sooty). The aroma profiles
generated were more influenced by the preparation stages and degrees of roasting than the coffee
varieties.