Effects of Sucrose, Guar Gum, and Carboxymethylcellulose on the Release of Volatile Flavor Compounds under Dynamic Conditions

Abstract

The effect of viscosity and thickener type (sucrose, guar gum, and carboxymethylcellulose) on dynamic flavor release was tested with model flavor solutions at two equiviscous levels. Dynamic flavor release was measured under simulated mouth conditions in an apparatus at 37 °C, with a shear rate of 100 s-1. The volatilized flavors were swept in a flow of helium gas into a mass spectrometer for selected ion monitoring chemical ionization. A plot of time versus ion abundance was recorded for each data set. The highly volatile compounds showed a large decrease in maximum ion abundance (Imax) as viscosity increased. Carboxymethylcellulose, guar gum, and sucrose solutions with a viscosity of 160 mPa s showed 36, 44, and 86% decreases compared to water, respectively, for the release of α-pinene. Similarly, 1,8-cineole decreased 32, 40, and 70% and ethyl 2-methylbutyrate decreased 58, 63, and 94%, respectively. The less volatile compounds methyl anthranilate, vanillin, and maltol showed less of an effect. Thickened solutions of similar viscosity did not show the same flavor release, indicating that both viscosity and binding of flavors with the food matrix affect flavor release. Keywords: Viscosity; mass transfer; diffusion; volatility; flavor release; mouth; shear; Stokes−Einstein; thickeners; binding; hydrocolloid