The acidity and sourness of coffee brews (together with aroma and bitterness) have always been recognized as important attributes of their sensory quality (Ginz et al., 2000). Marbrouk and Deatherage established in 1956 that the acidity of coffee depends upon the degree of roast (Balzer, 2001). Although malic and citric acids are already present in the green coffee bean, most of the acidity is generated at the beginning of the roasting process.