Physicochemical properties and conformations of water-soluble peach gums via different preparation methods

Physicochemical properties and conformations of WEPG (water extracted peach gum), AEPG2.0 (alkali extracted peach gum, 2 M NaOH) and HPPG8 (H2O2 extracted peach gum, 8 h), prepared from the gum of Prunus persica Batsch, were investigated. The yields of WEPG, AEPG2.0 and HPPG8 were 77.25%, 82.60% and 83.34%, respectively. All of the three peach gums were arabinogalactan-type polysaccharides with similar chemical composition. Conformational analysis revealed that WEPG, AEPG2.0 and HPPG8 were macromolecules with compacted coil structures and their molecular weights of 1.34 × 107 g/mol, 1.64 × 107 g/mol and 5.17 × 106 g/mol, respectively. Rheological test showed that WEPG, AEPG2.0 and HPPG8 exhibited non-Newtonian behavior, and their apparent viscosities followed the order of AEPG2.0 > WEPG > HPPG8. Results also indicated that all of the three peach gums significantly (P < 0.05) enhanced the stability of whey protein isolate oil-water emulsions, and AEPG2.0 was the optimal gum extract showing no phase separation over 5 weeks, suggesting it could be used as an effective stabilizer in food emulsions and beverage industry.