Steady shear flow properties of Cordia myxa leaf gum as a function of concentration and temperature.
The steady shear flow properties of dispersions of Cordia myxa leaf gum (CMLG) were determined as a function of concentration (0.5-2.5%, w/w), and temperature (10-50 °C). The CMLG dispersions exhibited strong shear-thinning behavior at all concentrations and temperatures. The Power-law (Ostwald-Waele's) and Herschel-Bulkley models were employed to characterize flow behavior of CMLG solutions at 0.1-100 s(-1) shear rate. Non-Newtonian shear-thinning behavior was observed at all temperatures and concentrations. While increase in temperature decreased the viscosity and increased the flow behavior indices, adverse effect was obtained by increasing the concentration. The Power-law model was found the best model to describe steady shear flow behavior of CMLG. The pseudoplasticity of CMLG increased markedly with concentration. An Arrhenius-type model was also used to describe the effect of temperature. The activation energy (Ea) appeared in the range of 5.972-18.104 kJ/mol, as concentration increased from 0.5% to 2.5%, at a shear rate of 10 s(-1).
Department of Food Science and Technology, Collage of Agricultural and Natural Resources, Ahvaz Branch, Islamic Azad University, Ahvaz, Iran.
Mahmood
M
Chaharlang
Department of Food Science & Technology, Ramin Agricultural & Natural Resources University, Ahvaz, Iran. Electronic address: uniquehimlen@gmail.com.
Vahid
V
Samavati
D031213:Cordia / Q000737:chemistry*; D053149:Plant Gums / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D012212:Rheology; D033081:Shear Strength; D013535:Suspensions; D013696:Temperature; D013816:Thermodynamics; D014783:Viscosity
D053149:Plant Gums; D013535:Suspensions
Cordia myxa leaf; Gum; Modeling; Rheology