Are Emerging Non-Thermal Technologies a Viable Solution for Extending the Shelf Life of Rehydrated Cod Products Under Refrigeration?

Cod has long held substantial economic and cultural importance in northern European societies. Today, rehydrated cod, obtained by desalting salted and dried products, is increasingly marketed as a ready-to-cook seafood product but remains highly perishable. The increased water activity, reduced salt content, and structural modifications induced by rehydration can promote microbial growth and quality deterioration, resulting in a limited refrigerated shelf life. This review critically examines available evidence on emerging non-thermal technologies for rehydrated cod, considering how rehydration-induced changes may influence treatment performance. High-pressure processing (HPP), non-thermal atmospheric plasma (NTAP), ultraviolet (UV) radiation, pulsed light, ozonation, and other approaches are evaluated in terms of their antimicrobial effectiveness, effects on quality, advantages, and limitations. Available evidence indicates that HPP is the most extensively investigated technology for delaying microbial spoilage, whereas evidence supporting NTAP, UV radiation, and pulsed light remains limited and does not establish their effectiveness as stand-alone treatments. Hurdle strategies warrant further investigation, although treatment interactions and outcomes depend strongly on matrix properties and processing conditions. Preservation strategies must therefore be optimized and validated directly in rehydrated cod rather than extrapolated from other seafood matrices. Further studies under industrially relevant conditions are needed to establish treatment efficacy and support industrial implementation.