Valorization of Eco‐Friendly Nanochitosan Particles on the Production of Low‐Sodium Smoked Fish Products

ABSTRACT Smoked fish products are widely consumed; however, they often contain high sodium levels (up to 4 g NaCl/100 g), which are associated with an increased risk of hypertension and cardiovascular diseases. Therefore, developing low‐sodium alternatives without compromising product quality and safety has become an urgent public health priority. This study evaluated the effectiveness of two nano‐saline brining solutions—NaCl/CS NPs (20% NaCl + 0.2% chitosan nanoparticles) and NaCl/KCl/CS NPs (15% NaCl + 5% KCl + 0.2% chitosan nanoparticles) in producing low‐sodium hot‐smoked mackerel fillets and cold‐smoked roe of gray mullet. Characterization of the synthesized nano‐saline formulations was carried out to confirm particle size, morphology, and structural properties. Treated products were assessed for sodium chloride, potassium, sodium content, sensory attributes, physical properties, nutritional contribution, as well as biochemical and microbiological stability over 30 days of refrigerated storage. Both nano‐formulations significantly reduced sodium content. The NaCl/KCl/CS NP solution achieved sodium reductions of up to 58% in mackerel fillets and 53.3% in mullet roe, with corresponding reductions in NaCl content of up to 73.1% and 72.8%, respectively. The NaCl/CS NP formulation reduced sodium content by 40% in mackerel fillets and 32% in mullet roe, along with NaCl reductions of 48.6% and 42.56%, respectively. Treated samples exhibited good sensory acceptability, lower pH and water activity, and microbiological safety; other technological and physical properties were also preserved or enhanced. Nano‐saline brining using NaCl/CS NPs and NaCl/KCl/CS NPs offers a promising strategy for producing healthier smoked fish products with significantly reduced sodium content, without compromising safety or quality.