Influence of soybean soluble polysaccharides and beet pectin on the physicochemical properties of lactoferrin-coated orange oil emulsion

Based on electrostatic layer-by-layer deposition, the influence of soybean soluble polysaccharides (SSPS) and beet pectin (BP) on the physicochemical properties of lactoferrin-coated orange oil emulsion was investigated. The physicochemical stability of orange oil emulsions was characterized by droplet size and distribution, zeta-potential, turbidity, rheological behavior, transmission profiles using LUMiSizer and degradation of volatile compounds in the emulsions during the storage. Results showed that the droplet characteristics of secondary emulsions were greatly dependent on the polysaccharides concentration and type. The zeta-potential values were decreased from 39.5 mV to −23.2 mV and −37.6 mV, respectively, for the SSPS and BP concentrations from 0 to 0.75 wt%, which indicated that anionic polysaccharides were adsorbed to the droplet surfaces. SSPS and BP concentration of 0.35 wt% was sufficient to saturate the LF-coated droplets and preferred effectively to increase the physical stability of the emulsion systems. During the storage of 4 weeks at 55 °C, SSPS and BP could significantly (p < 0.05) enhance the physical stability of emulsions and protect volatile compounds (decanal, octanal, geranial and limonene) from the oxidation. The least degradation of volatile compounds occurred in LF-BP coated emulsion. These results revealed that the physicochemical stability of LF-coated orange oil emulsions has been improved by the adsorption of anionic polysaccharides.