The Rheology of Colloidal and Noncolloidal Food Dispersions

Abstract

Rheological data on a food together with data on its composition and structure or microstructure should lead to understanding the interrelationships between them. A number of foods are dispersions of solids in liquids, liquids in liquids, or gas in liquids. The dispersed particles may be colloidal in nature with dimensions < 10 µm, or larger noncolloidal particles (> 10 µm). For both colloidal and noncolloidal dispersions (either in dilute or concentrated regimes), several theoretical equations exist that provide insights into the role of key rheological parameters, such as particle volume fraction and size, interparticle forces, and fractal dimension on their viscosity, yield stress, and modulus. When theoretical models cannot be easily applied to foods with complex structures, structural analysis and structure-based models provide insight into the role of solids loading and interparticle bonding on rheological behavior. In this review, recent studies on colloidal and noncolloidal food dispersions in which theoretical models as well as structural analysis were employed are discussed.

Estudo Da Estabilidade, Comportamento Reológico E Efeito Da Temperatura Da Polpa De Cupuaçu (Theobroma Grandinflorum) Em Diferentes Concentrações

“…Onde, μ é a viscosidade dinâmica (Pa.s), η é o índice de comportamento (adimensional), γ é a taxa de deformação (s -1 ) e k é o índice de consistência (Pa.s) (Steffe, 1996;Genovese et al, 2007).…”

Preparation and characterization of sub-micron dispersions of sand in ethylene glycol-water mixture

“…The literature data on the temperature influence on relative viscosity is scattered, with a majority of them indicating negligible influence of temperature on relative viscosity (Longo and Zilio, 2011;Vajjha et al, 2010;Chen et al, 2007), while a few others observed an influence of temperature (Nguyen et al, 2007;Duangthongsuk and Wongwises, 2009;Lee et al, 2011). Interparticle forces, Brownian motion and hydrodynamic forces determine the viscosity of a colloidal dispersion (Genovese et al, 2007). At low shear rates, interparticle forces and Brownian motion dominate (Genovese et al, 2007).…”

“…Interparticle forces, Brownian motion and hydrodynamic forces determine the viscosity of a colloidal dispersion (Genovese et al, 2007). At low shear rates, interparticle forces and Brownian motion dominate (Genovese et al, 2007). Brownian motion and interparticle forces are temperature-dependent.…”

Effect of the addition of hydrocolloids and aloe vera gel (Aloe barbadensis Miller) on the rheological properties of a beverage of sweet corn (Zea mays var. saccharata)

“…Hydrocolloids are hydrophilic polymers widely used in food systems because of their ability to modify rheological properties, providing a viscosity modification, forming gel structures or stabilizing suspended particles, among other properties, thus prevent phase separation is generally associated with poor quality [2,3]. The addition of gums, such as CMC, xanthan gum, Arabian gum, gellan gum and guar gum, has been studied recently in the formulation of beverages [4][5][6][7][8].…”