Temperature dependence of the formation and melting of pectin–Ca2+ networks: a rheological study

摘要: Abstract Small deformation dynamic rheometry was used to characterise the calcium-induced gelation of low-methoxyl pectins, at two different pH values. The kinetics interpreted with basis on change storage modulus time, taken as a measure changes in cross-linking density within pectin–calcium network. temperature influence rate gel formation and ageing evaluated, well sensitivity cured gels. softening/melting networks were also studied under non-isothermal conditions. structural diversity pectin samples had great thermal behaviour these networks, due differences steric arrangement or environment and/or availability chelating groups. An association mechanism is suggested predominate conditions low dissociated carboxylic groups, pH, higher degree methylation, constraints introduced by acetylation neutral side chains, from classical ‘egg-box’ model, where non-ionic hydrogen bonding hydrophobic interactions may co-exist cooperate coordinative binding calcium-ions.