Relationships between the behavior of three different sources of pectin at the oil-water interface and the stability of the emulsion

In this study, structural characterization and chemical compositions of three pectins from different sources were studied, which showed that compared with apple pectin (AP) and citrus peel pectin (CPP), sugar beet pectin (SBP) has higher protein contents, feruloylated groups, acetyl groups and more hairy regions. Molecular dynamics simulations showed that HG domain was tiled on the oil-water interface, while RG-Ⅰ and RG-Ⅱ domains were adsorbed on the oil-water interface in a folded form, resulting in a thick viscoelastic film. Dissipative quartz crystal microbalance (QCM-D) and dilatational rheology studies showed that under high-concentration and acidic conditions, pectin molecules were adsorbed in multiple layers at the oil-water interface, forming a thicker viscoelastic film, which was crucial for the long-term stability of pectin-stabilized emulsions.