The sustained-release mechanism of citrus essential oil from cyclodextrin/cellulose-based Pickering emulsions

Abstract

The design of functional delivery systems is crucial for achieving sustained flavor release in food products. In this study, we compared the stabilizing effects of β-cyclodextrin (CD)-based Pickering emulsions loaded with lemon essential oil (LEO) mediated by cellulose nanocrystals (CNC) and bacterial cellulose (BC). We also explored the potential mechanisms underlying the sustained flavor release in terms of emulsion properties, droplet micromorphology, and interfacial properties. CNC and BC mediation improved the overall stability of emulsions, primarily reflected by increased droplet dispersion and a slight reduction in droplet size (from 10.83 μm to 6.20 and 6.99 μm, respectively). High concentrations (0.12% and 0.24%) of BC mediation led to a sharp increase in emulsion viscosity (from 56.60 to 1872.57 and 6194.29 mPa s, respectively), and the strong network formed by BC in the continuous phase prevented droplet migration. In contrast, the distribution of CNC at the oil-water interface allowed droplets to possess a double-layer interfacial structure, effectively enhancing interfacial tension and interfacial dilatation modulus, and creating a greater barrier to LEO diffusion. These findings provide a scientific basis for the structural design of delivery systems to achieve regulated release of flavor factors.