The Valorization Potential of Freshwater Fish, Including Common Carp (Cyprinus carpio), in the Context of Obtaining Functional Food Ingredients

Freshwater fish represent an underutilized source of bioactive compounds with potential applications in food enrichment and functional food design. This article reviews the current state of knowledge regarding bioactive components derived from freshwater fish, including proteins, amino acids, protein hydrolysates, bioactive peptides, lipids and polyunsaturated fatty acids, polysaccharides, pigments, minerals, vitamins, and other compounds of high functional value. Particular attention is paid to their biological and technological properties and potential applications in food products. Conventional and modern extraction and processing technologies used on an industrial scale are also discussed. Furthermore, the importance of biorefinery as a tool for the comprehensive management of freshwater fish biomass is presented. Available data indicate significant potential for bioactive components derived from freshwater fish, but their wider application requires further research to optimize recovery processes and their use in real food matrices.