Characterisation of a novel gel system containing pectin, heat inactivated pectin methylesterase and NaCl

An interesting and novel gelation system is described consisting of pectin, heat inactivated pectin methylesterase and NaCl. Gelation occurs at pH values ranging from 3 to 7, with gels formed at lower pH values being more stable. The rheological properties of the gel depend on the concentration of its components and the temperature at which gel formation takes place. Under optimum conditions, storage moduli can reach values of >1000 Pa. Disruption of the gel network by increasing the temperature to 65°C is reversible upon cooling, yielding gels whose strength is very similar to that of the original gel. Experimental data suggest that mainly hydrophobic interactions and hydrogen-bonding contribute to the formation and stabilisation of junction zones whereas electrostatic interactions play only a minor role.