Sensory Properties of Under-Roasted Coffee Beverages

Conditions milder than standard roasting (under roasting:140-170°C for 20-12 min) have been proposed to reduce the formation of potentially harmful compounds developing during standard coffee roasting. In the present study, sensory properties of brews prepared with under roasted coffees (140 to 165°C for 20 min) were described by Descriptive Analysis. Two meta-attributes were defined: “coffee” consisting of attributes positively related to the increasing of process temperature and “no-coffee” consisting of those negatively related to temperature. The progressive lowering of “no-coffee” and the corresponding increasing of “coffee” mean values were induced by temperature increasing in under roasting conditions. The processing temperature of 150°C seems to represent the changing point between the two meta-attributes with “no-coffee” prevailing at lower and “coffee” at higher temperatures. Consumer responses indicate the positive effect of both product processing temperature and “coffee” attribute intensity on liking. Brews from coffee treated at temperature lower than 150°C, showed a sensory profile characterized by “no-coffee” attributes and resulted the less preferred by regular coffee consumers. Practical Applications Results from this study represent a contribution to the description of the sensory properties of coffee beverages obtained by means thermal processes milder than standard roasting. A new set of sensory descriptors, and relative reference standards, was defined to describe the specific sensory properties of beverages from under roasted coffee. Furthermore, thermal treatment conditions leading to under roasted coffee beverages accepted by coffee regular consumers were determined.