Model studies on the influence of coffee melanoidins on flavor volatiles of coffee beverages

Addition of the total melanoidin fraction isolated by water extraction from medium-roasted coffee powder to a model solution containing a set of 25 ar oma compounds mimicking the aroma of a coffee brew reduced, in particular, the intensity of the roasty, sulfury aroma quality. Model studies performed by static headspace analysis revealed that especially three well-known cof fee odorants, that is, 2-furfurylthiol (FFT), 3-methyl-2-butene-1-thiol, an d 3-mercapto-3-methylbutyl formate, were significantly reduced in the heads pace above an aqueous model solution when melanoidins were added. In partic ular, the low molecular weight melanoidins (1500-3000 I)a) led to the most significant decrease in FFT. In contrast, for example, aldehydes remained u naffected by melanoidin addition.