Preparation and characterization of zein–caseinate–pectin complex nanoparticles for encapsulation of curcumin: pectin extracted by high‐speed shearing from passion fruit (Passiflora edulis f. flavicarpa) peel

BACKGROUND Pectin extracted by high‐speed shearing from passion fruit peel (HSSP) is a potentially excellent wall material for encapsulating curcumin, which has multiple advantages over pectin prepared by heated water extraction. HSSP was used to fabricate complex nanoparticles of zein–sodium caseinate–pectin for encapsulation of curcumin in this study. The influence of heating on the physicochemical properties of the composite nanoparticles was also investigated, as well as the effect of composite nanoparticles on the encapsulation efficiency, antioxidant activity and release characteristics of curcumin. RESULTS The nanoparticles were formed through electrostatic interactions, hydrogen bonds and hydrophobic interactions between the proteins and HSSP. A temperature of 50 °C was more favorable for generating compact and small‐sized nanoparticles, which could effectively improve the encapsulation efficiency and functional properties. Moreover, compared to other pectin used in the study, the nanoparticles prepared with HSSP showed the best functionality with a particle size of 234.28 ± 0.85 nm, encapsulation rate of 90.22 ± 0.54%, free radical scavenging rate of 78.97% and strongest protective capacity in simulated gastric fluid and intestinal release effect. CONCLUSION Zein–sodium caseinate–HSSP is effective for encapsulating and delivering hydrophobic bioactive substances such as curcumin, which has potential applications in the functional food and pharmaceutical industries.