Physicochemical characterization and emulsifying properties evaluation of RG-I enriched pectic polysaccharides from Cerasus humilis.

Abstract Rhamnogalacturonan I (RG-I) enriched pectic polysaccharides (CSP) were extracted from Cerasus humilis fruits (RG-I: 74.46%). Structural characterization including FTIR, XRD, NMR, HPAEC and SEM demonstrated that CSP was a high-methoxy acetylated pectin macromolecule with abundant arabinose and galactose side chains (DM: 53.41%, MW: 1098 kDa, (Ara + Gal)/Rha: 5.37%). CSP afforded additional lipid oxidation stability for emulsions, and exhibited significantly better emulsification performance than citrus pectin. In addition, CSP formed a weak gel network that stabilized the emulsions (G′ > G″). Interestingly, CSP had behaviors that are divergent from those of commercial high-methoxy pectin because it demonstrated potential in forming sugar-free gels systems. Overall, Cerasus humilis is a new source of pectin rich in RG-I. CSP can be used as a novel emulsifier with gelling and antioxidant effects, providing its alternative application as a natural emulsifier and rheological modifier in a wide range of products, including those with oil-in-water and low sugar.