Search

The purpose of this study was to prepare Pickering emulsion with synergistic antibacterial effect using whey protein isolated-citral (WPI-Cit) nanoparticles with eugenol for grape preservation. In this emulsion, eugenol was encapsulated in oil phase. The particle size, ζ– potential, and antibacterial mechanism of the nanoparticles were characterized. The rheological properties, antibacterial effects and preservation effects of WPI-Cit Pickering emulsion were measured. The results showed that the optimal preparation condition was performed at WPI/Cit mass ratio of 1:1, WPI-Cit nanoparticles were found to damage the cell wall and membrane of bacteria and showed more effective inhibition against S. aureus. Pickering emulsion prepared with WPI-Cit nanoparticles exhibited a better antibacterial effect after eugenol was encapsulated in it, which extended the shelf life of grapes when the Pickering emulsion was applied as a coating. It demonstrated that the Pickering emulsion prepared in this study provides a new way to extend the shelf life. [Display omitted] • Whey protein isolate and citral nanoparticles were prepared by Schiff reaction. • Whey protein isolate and citral nanoparticles damaged bacteria cell wall and DNA. • Whey protein isolate-citral Pickering emulsion had antibacterial properties. • Whey protein isolate-citral Pickering emulsion and eugenol extend grape shelf life. [ABSTRACT FROM AUTHOR]

• Nanoemulsion (NE) was used to encapsulate docosahexaenoic acid (DHA)-rich fish oil. • Octenyl succinic anhydride-modified chitosan (OSA-CS) was used as coating material. • OSA-CS-coated and CS-coated nanoemulsion (OSA-CS-NE and CS-NE) was compared. • OSA-CS-NE had better storage stability and stability against ambient stresses. • OSA-CS-NE could deliver more DHA into the small intestine. Octenyl succinic anhydride-modified chitosan (OSA-CS) was synthesized and applied as a coating material to enhance the stability of docosahexaenoic acid (DHA)-loaded nanoemulsion. Due to the presence of the positively charged OSA-CS coating, the nanoemulsion exhibited a high positive zeta potential and two different layers. Compared with natural CS-coated nanoemulsion, OSA-CS-coated nanoemulsion showed improved storage stability (physical and chemical stability) and stability against environmental stresses (ionic strengths, temperatures and pH). Besides, OSA-CS-coated nanoemulsion protected encapsulated DHA from simulated gastric fluid damage better than that of natural CS-coated nanoemulsion, suggesting that OSA-CS-coated nanoemulsion had the potential to deliver more DHA into the small intestine. In conclusion, based on the comparison of two coating materials, natural chitosan and OSA-CS, it was found that the encapsulated nutrient was better protected by the OSA-CS coating. Such a finding will provide insights to broaden the application of modified chitosan in food delivery systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • The nanoparticles were prepared by Schiff base reaction of WPI and vanillin. • WPI-Van nanoparticles exhibited good bacteriostatic effect. • Pickering emulsion based on WPI-Van nanoparticles had excellent storage stability. • The retention rate and bioaccessibility of V E encapsulated in emulsion were improved. The purpose of this work was to prepare Pickering emulsion stabilized by bacteriostatic whey protein isolate–vanillin (WPI–Van) nanoparticles as a carrier for encapsulating vitamin E. The particle size, ζ potential, PDI were used to study the optimal preparation conditions of nanoparticles. The results showed that the optimal preparation condition was achieved at WPI/Van mass ratio of 3:1. FTIR spectra demonstrated the complexation of WPI and Van. SEM image showed spherical and slightly rough surface of nanoparticles. Inhibitory effects of nanoparticles on E. coli and S. aureus were also observed. After storage of 21 days at 4 °C, the retention rate of vitamin E in the emulsions remained 43% higher than that of unencapsulated vitamin E. Moreover, the release rate of vitamin E encapsulated in emulsions in the small intestine was 81%, indicating excellent bioaccessibility. The research can provide a new insight for production and application of antibacterial Pickering emulsions. [ABSTRACT FROM AUTHOR]