PERCEPTION OF FAT IN A MILK MODEL SYSTEM USING MULTIDIMENSIONAL-SCALING

This study examined the contributions of stimulus fat content and flav or volatiles to the perception of fat in a milk model system. The mode l system was formulated by adding bland vegetable oil (0%, 5%, or 10% w/v) and natural cream flavor (0%, 0.5% or 1% w/v) to a skim milk base . Panelists judged pairs of samples for similarity on the basis of thr ee attributes (fat content, mouthcoating and thickness) and the result s were analyzed using a multidimensional scaling procedure. Two-dimens ional solutions best represented the data. The stimulus spaces for fat content and mouthcoating were visually similar to each other and prov ided reasonable separation of the samples. instrumental measures helpe d to define the underlying dimensions of the stimulus space for fat co ntent. Dimension I related to texture and included the contributions o f viscosity, and fat particle size and number distribution; dimension 2 related to flavor perception. The sample with a moderate fat content (5%) and the highest concentration of added cream flavor (1%) was per ceived to be similar to the 10% fat samples with added flavor. Thus, t he added flavor provided the sensation of higher fat content. These da ta suggest that flavor plays an important role in the preception of fa t in dairy foods. A psychophysical model of fat perception in dairy fo ods is proposed which includes the contribution of viscosity, fat part icle size and number distribution, and volatile flavor perceptions.