Marine-derived alginate oligosaccharides as functional modulators for sodium reduction in coated frozen foods: molecular mechanisms, batter matrix engineering, and sensory compensation: a systematic review

Excessive sodium consumption is closely linked to hypertension and cardiovascular illnesses, leading to worldwide initiatives aimed at decreasing salt content in processed foods. Most of the included studies focused on conventional sodium alginate-based hydrocolloid systems, whereas comparatively limited evidence was available for alginate oligosaccharides (AOS) in sodium-reduced, coated, frozen-food applications. Coated frozen foods, including battered fish, chicken nuggets, and fried potato items, significantly contribute to sodium consumption due to the prevalent use of salt for flavor enhancement, batter efficacy, and moisture regulation. Alginate oligosaccharides (AOS), derived from brown seaweed alginate and obtained by depolymerization, have recently attracted interest as multifunctional food hydrocolloids that can influence microstructure, water retention, and flavor perception in reduced-sodium formulations. This systematic analysis assesses peer-reviewed literature published from 2005 to 2025 on the function of alginate or alginate-derived hydrocolloids in sodium-reduction techniques in coated and fried food systems.