Hydrodynamic properties of whole arabic gum

Abstract

The most economically important of the hydrodynamic properties of a material are viscosity and density, which allow determining the intrinsic viscosity of raw materials used in the food industry. They serve as an indirect measure of molecular weight (M), hydrodynamic radius (RH), number of Simha, (ν(P)), Perrin parameter (P); hydration value (δ), Scheraga-Mandelkern parameter (β), and Flory parameters (0 and P0). Normally, these parameters are reported at a temperature of 25ºC, which limits their use at different temperatures. This work studies the temperature-dependence of whole arabic gum (WAG) in aqueous solution, finding that in aqueous solution, this biopolymer presents a random coil shape with ν(p) ≈ 2.55. The behavior of WAG in this system indicates that it behaves as a colloidal particle that tends to compact as temperature increases (RH decrease). The M of WAG calculated here are 760000 g/mol. The Mark-Houwink-Sakurada equation constants, a and k, for WAG in water solvent-temperature systems have been reported already, where the value of a ranges from 0.5496 to 0.5085 within a temperature range of 20 to 50°C.