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The molecular structure, rheological properties, microstructure and physical stability of oil-in-water emulsions using octenyl succinic-sugary maize soluble starch (OS-SMSS) were investigated and compared with two commercial OS-starches (HI-CAP 100 and Purity Gum 2000). The degree of substitution (DS), weight-average molecular weight (Mw) and z-root mean square radius of gyration (Rz) of OS-SMSS, HI-CAP 100 and Purity Gum 2000 were 0.0050, 223.4 × 10 5 g/mol and 38.8 nm, 0.0037, 9.6 × 10 5 g/mol and 29.3 nm, and 0.0031, 31.3 × 10 5 g/mol and 39.6 nm, respectively. FT-IR spectra showed two new absorption bands at 1725 and 1570 cm −1 from OS ester linkage in all tested samples. The emulsion with OS-SMSS exhibited a pseudoplastic behavior over the whole shear rate range, whereas other two emulsions showed a similar Newtonian fluid. All hydrophobic starch stabilized emulsions satisfied the Herschel–Bulkley model. All emulsions displayed storage modulus (G′) was higher than loss modulus (G″), and only G′ and G″ of OS-SMSS stabilized emulsion were independent of frequency. The volume-average droplet size ( d 43 ) value of emulsions stabilized by three modified starches was 27.9, 15.2 and 24.4 μm, respectively. During 4 weeks storage, lower change in d 43 of emulsion with OS-SMSS was observed. The above results with schematic models of emulsions suggested that an emulsion with high stability could be prepared using 3% of OS-SMSS due to the formation of high density and thick nanoparticle layer at the interface, indicating OS-SMSS was a Pickering emulsion stabilizer for good long-term stability. [ABSTRACT FROM AUTHOR]

• OSA-SMDG-stabilized emulsions incorporated with β -carotene had high encapsulation efficiency. • OSA-SMDG-based emulsions improved storage stability of β -carotene. • OSA-SMDG-based emulsions promoted antioxidant activity of β -carotene and protected cells against oxidative stress. • Higher concentration of OSA-SMDG in Pickering emulsion enhanced bioaccessibility of β -carotene. The impact of sugary maize dendrimer-like glucan octenyl succinate (OSA-SMDG) on the storage stability and antioxidant activity of β -carotene (BC)-loaded emulsions as well as bioaccessibility were investigated. The encapsulation efficiency of β -carotene in emulsions containing 3% OSA-SMDG (3OSA-SMDG-BC) or 5% OSA-SMDG (5OSA-SMDG-BC) was 89.6% and 94.9%, respectively. The antioxidant activity of both emulsions was higher than that of pure β -carotene. During simulated digestion, the particle size of emulsions was immediately reduced, whereas zeta-potential was continuously increased in intestinal digestion. After 2 h digestion, the free fatty acids (FFA) release rate of 3OSA-SMDG-BC and 5OSA-SMDG-BC was significantly higher than that of blank emulsion. Bioaccessibility of β -carotene encapsulated in 3OSA-SMDG-BC and 5OSA-SMDG-BC was also significantly higher than that of blank emulsion. FFA release rate and β -carotene bioaccessibility of 5OSA-SMDG-BC were higher than that of 3OSA-SMDG-BC. These results demonstrated that OSA-SMDG could be used to fabricate food-grade O/W Pickering emulsion as a delivery system for bioactive compounds. [ABSTRACT FROM AUTHOR]