Formation of low environment-sensitive whey protein isolate-dextran/chondroitin sulfate nanoparticles for...

Cinnamaldehyde is regarded as a secure antibacterial agent for various food matrices, but the volatility and insolubility restrict its application. Biopolymer nanoencapsulation was emerging as an effective tool to address these drawbacks. However, current nanoparticle fabrication methods enabled cinnamaldehyde protection and sustained release only under narrow pH ranges and low ionic strength, failing to provide simultaneous compatibility with the diverse pH and ionic strength variations encountered in complex food systems. Herein, whey protein isolates-dextran/ chondroitin sulfate (WPI-dextran/ChS) nanoparticles applicable to most of the food systems with varied pH (1-10) and salt level (0-2 mol/L) were obtained based on Maillard reaction and heat-induced gelation. Dynamic light scattering, encapsulation efficiency and loading capacity indicated that the nanoparticles prepared from WPI-dextran conjugates with 3-day incubation exhibited relatively better dispersity and loading ability for cinnamaldehyde. Better antioxidant and antibacterial ability were also observed, with DPPH and ABTS radical scavenging rates of 55.08 % and 47.42 %, lipid peroxidation inhibiting activity of 48.24 %, and the antibacterial efficiency of 83 % and 89 % against E. coli and S. aureus, respectively. The excellent performance of cinnamaldehyde-loaded nanoparticles in preservation of sauced pork was corroborated by multiparametric analysis, which showed that the deterioration of sauced pork was significantly retarded.