Determination of potent odourants in roasted coffee by stable isotope dilution assays

Abstract Stable isotope dilution assays were developed for 14 important odourants of roasted coffee. The following amounts (mg/kg) were found in the Arabica (I) and the Robusta (II) coffees: 2‐furfurylthiol (1.08 I, 1.73 II), methional (0.24 I, 0.095 II), 3‐mercapto‐3‐methylbutyl formate (0.13 I, 0.115 II), 2‐ethyl‐3‐5‐dimethylpyrazine (0.33 I, 0.94 II), 2,3‐diethyl‐5‐methylpyrazine (0.095 I, 0.31 II), guaiacol (4.2 I, 28.2 II), 4‐vinylguaiacol (64.8 I, 177.7 II), 4‐ethylguaiacol (1.63 I, 18.1 II), vanillin (4.8 I, 16.1 II), ( E )‐β‐damascenone (0.195 I, 0.205 II), 4‐hydroxy‐2,5‐dimethyl‐3(2 H )‐furanone (109 I, 57 II), 3‐hydroxy‐4,5‐dimethyl‐2(5 H )‐furanone (1.47 I, 0.63 II), 5‐ethyl‐3‐hydroxy‐4‐methyl‐2(5 H )‐furanone (0.16 I, 0.085 II), 5‐ethyl‐4‐hydroxy‐2‐methyl‐3(2 H )‐furanone (17.3 I, 14.3 II).