The Effect of Viscosity on the Perception of Flavour

TLDR

Flavour perception in viscous solutions is influenced by hydrocolloid concentration, and models are needed to capture these effects. A trained sensory panel evaluated flavour and sweetness intensity in solutions with varying HPMC, sugar, and flavour volatile concentrations, using magnitude estimation and controlled modulus, while volatile release was measured by MS Nose™. Increasing HPMC concentration above 0.6 g/100 g reduces perceived flavour and sweetness intensity, with the decline aligning with the random coil overlap point c*, yet the actual volatile release measured in breath remains unchanged.

Abstract

A trained sensory panel assessed flavour and sweetness intensity in solutions containing varying concentrations of hydroxy propyl methylcellulose (HPMC), sugar and flavour volatile. The flavour and sweetness of the viscous solutions were rated using magnitude estimation with a controlled modulus. In addition, the concentration of volatile released on the breath was measured using MS Nose™. For low concentrations of HPMC (<0.5 g/100 g), perceived flavour intensity remained the same; however, a steady decrease was noted at higher concentrations (>0.6 g/100 g). The change in perceived intensity occurred at the point of random coil overlap (c*) for this hydrocolloid. The perceived sweetness of the solution showed a similar pattern with increasing HPMC concentration, although the inflection at c* was not so obvious. Despite the change in perceived flavour intensity, the actual concentration of volatile measured on the breath was not affected by the change in HPMC concentration. Low-order polynomial models were produced to describe perceived flavour intensity and sweetness in viscous solutions containing HPMC and potential explanations for the changes in perception are discussed.