Quantification of sensory difference thresholds for fat and sweetness in dairy-based emulsions

Abstract

The ongoing increase of nutrition-related diseases is a continuous challenge in the development or improvement of foods. Although fat is important as regards energy reduction, no quantitative data are available on the sensory sensitivity of the human towards fat content in complex emulsions. After developing vanilla custards which varied in fat content (1–29g/100g) but were controlled with respect to viscosity, sweetness and flavor, the constant stimulus method was used to determine the difference threshold for fat. Irrespective of reference fat concentration (5, 15 and 25g/100g), difference thresholds were found to be almost constant at 14–15g/100g. In another set of experiments sweetness difference thresholds were determined for reference sugar concentrations of 3%, 6% and 12% at different levels of fat content. Weber fractions for sweetness slightly decreased with increasing reference concentration. At higher sugar concentration levels, a higher sensitivity of the subjects towards sweetness differences was observed when the fat content of the emulsions was increased.