Perceived Sweetness and Redness in Colored Sucrose Solutions

Perceived sweetness and redness in five red colored solutions containing 0.25–5.0% FD&C Red 40 were quantified using magnitude estimation. Three panels of 14 subjects each evaluated solutions containing five sucrose concentrations ranging from 2.7–5.3%. Color had a statistically significant effect (p≤0.05) on sweetness perception in 80% of the treatments. Sweetness in darker colored solutions was 2–10% greater than the lighter reference when the actual sucrose concentration was 1% less. Sweetness increased linearly over all sucrose concentrations and over a narrow range of color intensities. Color was measured using the Gardner XL-23 Colorimeter and the G.E. Recording Spectrophotometer. All color measurements were converted to L*, a*, b* and the value arctan (a*/b*) - used to represent color intensity. The perception of increasing color intensity was a linear power law function of arctan (a*/b*).