Quaternized chitosan-based hollow salts as a novel curing strategy for dry-cured meat: enhancing NaCl diffusion, protein hydrolysis, and sensory quality in air-dried duck

Traditional dry-cured meats typically contain excessive amounts of NaCl. This study introduces a novel technique using quaternized chitosan-based hollow salt to cure duck for air-dried production, aiming to reduce NaCl usage while improving product quality. Compared with traditional NaCl curing, substitution with hollow salt significantly enhanced Na⁺ diffusion in muscle and accelerated its release during mastication, thereby reducing overall NaCl usage and enhancing early saltiness perception. A moderate substitution level (particularly 60%) optimally activated endogenous muscle protease activity, promoted myofibrillar protein degradation, and increased the accumulation of free amino acids. A total of 62 volatile flavour compounds were identified in air-dried duck, with results indicating that hollow salt substitution slightly diminished the aromatic intensity. However, sensory attributes such as colour, texture, taste, and overall acceptability were significantly improved. This study provides a promising strategy for developing healthier and more palatable dry-cured meat products.