Micro- and nano-encapsulation technologies for enhanced flavour preservation in food systems: materials, mechanisms, challenges, and future perspectives

The preservation of volatile flavour compounds in foods remains challenging because of evaporation, oxidation, thermal and photo-induced degradation, and partitioning within complex food matrices. Microencapsulation provides established protection and scalable processing routes, whereas nanoencapsulation can offer additional control over interfacial area, dispersion, carrier structure, and release. This review critically compares micro- and nano-encapsulation for flavour preservation, distinguishing retention during manufacture from stability during storage and flavour release and perception during consumption. It examines nanoemulsions, nanoliposomes, solid lipid nanoparticles, nanostructured lipid carriers, protein- and polysaccharide-based nanocarriers, and selected hybrid systems, with emphasis on flavour chemistry, carrier–flavour interactions, release mechanisms, food-matrix effects, quantitative performance metrics, and sensory consequences. Nano-enabled packaging and nanosensing are considered only as indirect preservation or monitoring technologies and are explicitly distinguished from direct flavour delivery. The review further evaluates industrial scale-up, cost, technology readiness, safety, migration, regulatory requirements, and sustainability, alongside emerging approaches including AI-assisted formulation, machine learning, digital-twin modelling, microfluidic manufacturing, and precision flavour delivery. Overall, the review identifies when nanoencapsulation provides a meaningful technological advantage over microencapsulation and when conventional microencapsulation may remain the more practical choice.