Flavour-Matrix Interactions in Powder-Based Encapsulation: Mechanisms, Retention, and Food Applications

Food flavours are complex multi-component systems and have crucial impacts on the perception and acceptability of food products. Powder-based flavour encapsulation in various matrices, including wall materials, surfactants, and solvents, has been extensively applied to enhance oxidative and thermal stability, reduce volatile loss, and regulate flavour release. This review discusses current encapsulation strategies with emphasis on the fundamental flavour-matrix and matrix-matrix interactions in governing flavour stabilisation, release mechanisms, and sensory performance. Conventional wall materials (e.g. proteins, starches, and polysaccharides) and emerging systems (e.g. lipids, fibres, and cell-derived substances) provide diverse non-covalent interactions, including hydrophobic, electrostatic, and hydrogen bonding as well as covalent interactions such as Maillard reactions, disulphide cleavage, Schiff base formation, and/or Michael addition. Hydrophobic and electrostatic interactions usually act as the primary driving forces for flavour binding, while hydrogen bonds facilitate the dimensional compatibility and strengthen the encapsulation matrix via crosslinking. In contrast, covalent flavour-matrix interactions are usually associated with flavour loss and changes in sensory perception. This review highlights the importance of understanding flavour-matrix and matrix-matrix interactions to guide the rational design of encapsulation systems for targeted, stimuli-responsive flavour release and improved sensory perception in real food matrices.