Characterization and optimization of a new immobilized system of κ-carrageenan through interaction with carob bean gum and polyols

Abstract

The optimum relationships of κ-carrageenan and carob bean gum were investigated in order to obtain an immobilization system with better compression resistance, trapping capacity, and storage stability, and less syneresis phenomenon, when compared to κ-carrageenan itself. With that objective, different concentrations of polyols (glycerol and propylene glycol) were added, because of their water-retention characterization in the containing system. In this way, an improved system with good compression resistance was obtained: 15 × 10 −4 N/m 2 in modified κ-carrageenan gel without E. coli cells and 11 × 10 −4 N/m 2 with Escherichia coli cells. In the modified κ-carrageenan gel, the syneresis phenomenon decreased. The enzymatic activity in the system was 18 U/g, which did not present a change over a storage period of six months.