2.6.2. Roasted coffee

More than 700 components have been identified in roasted coffee.

Coffee is an excellent example to demonstrate the correlation between the pattern of precursors and the spectra of formed aroma and flavour components.

The major components of roasted coffee are furans and reductones. Arabicas contain higher amounts of furanaldehydes and furaneol than Robustas. The aldehydes and reductones are strecker-active components and further transformed into typical aroma and flavour components.

More than 100 sulfur compounds were characterized in roasted coffee and they are formed in distinct distributions, depending on the coffee types. The following compounds are some of these sulfur compounds.

High amounts of furfurylthiol, furfuryl methyl sulfide and furfuryl methyl dissulfide are typical ingredients in the oil of Robustas whereas Arabicas contain significant concentrations of 5-methyl- derivatives (at similar roasting levels) (Tressl, 1990).