Sensory optimization of a powdered chocolate milk formula

Abstract

Four experiments were carried out to optimize the formulation of a powdered chocolate milk. The first of these compared facial vs. verbal-numeric self-administered scales when measuring sensory acceptability of different attributes among 11-year-old children. Both scales were equivalent. In a second experiment, magnitude estimation was performed to analyze sensory viscosity as a function of gum concentration, and chocolate flavor as a function of cocoa concentration. Steven's Law exponents were: 0.37 for viscosity and 0.78 for chocolate flavor. Third, by using a minimum bias method, the optimum level of sugar concentration resulted in 5.0% for adults and 6.0% for children. In the fourth experiment gum and cocoa concentration were optimized using response surface methodology. Based on Steven's Law exponents, levels were varied geometrically. Contour plots for appearance, texture, flavor and overall preference are presented for children and adults. No unique formula would satisfy both age groups for all attributes.