Influence of temperature on the dynamic and steady-shear rheology of pectin dispersions

J. A. Lopes da Silva, M. P. Gonçalves*, M. A. Rao

*Autor correspondente para este trabalho

Resultado de pesquisarevisão de pares

68 Citações (Scopus)

Resumo

The influence of temperature on the dynamic and steady-shear theology of ionic polysaccharides, high-methoxyl and low-methoxyl pectins, has been studied and compared with the behaviour of locust bean gum, a virtually neutral biopolymer. Using the time-temperature superposition principle, the theological parameters were reduced to an arbitrary reference temperature. Activation energies were calculated and their dependence on temperature and shear rate analysed. Concerning the viscosity dependence on temperature, two approaches have been considered: one associated with the theory of absolute reaction rates leading to an Arrhenius type equation, and the other associated with the free volume theory, expressed by the Williams-Landel-Ferry equation. The difficulties encountered in the superposition of the dynamic properties of the pectin dispersions, the high activation energies, yield values and elastic plateau at low oscillatory frequency, are consistent with a macromolecular organization of these polymers dominated by important aggregation phenomena, which could be attributed to important intermolecular interactions like hydrogen bonding and hydrophobic interactions, especially in conditions of low degree of ionization of the carboxylic groups.
Idioma originalEnglish
Páginas (de-até)77-87
Número de páginas11
RevistaCarbohydrate Polymers
Volume23
Número de emissão2
DOIs
Estado da publicaçãoPublicado - 1994

Impressão digital

Mergulhe nos tópicos de investigação de “Influence of temperature on the dynamic and steady-shear rheology of pectin dispersions“. Em conjunto formam uma impressão digital única.

Citação