Degree of darkens
or time of roasting, type of roaster used and expected quality of
coffee (light, medium and dark) guide the roasting conditions
and affect the PAHs levels of the processed product. Dark coffee
blends like dark Sumatra undergoes higher degree of roasting for
longer duration to achieve its dark texture and desired aroma,
and thus exhibited highest contamination of PAHs over light and
medium coffee blends (Jiménez et al., 2014).