Title : Valorization of marine co-products: from lipid extraction using green processes to nutraceutical and food applications
Abstract:
Total fisheries and aquaculture production reached a record 214 million tons in 2020 (FAO, 2022). The expansion of fisheries processing and aquaculture production has resulted in increasing quantities of by-products, which may represent up to 60% of total biomass, including heads, skin, flesh, and bones. These marine resources are rich in nutrients and bioactive substances, such as proteins and long-chain n-3 polyunsaturated fatty acids (LC-PUFAs) that Global Health Authorities recommend consuming for their health benefits to prevent diseases.
Different marine sources, including fish by-products, sea cucumber, scallop, squid, and fish roe, can be valorized by conventional and non-conventional extraction techniques (solvents, supercritical fluid extraction, enzyme-assisted extraction…). Salmon by-products (Salmo salar) generated by the food chain represent a source of eicosapentaenoic acid (EPA 20: 5n-3) and docosahexaenoic acid (DHA 22: 6n-3) and peptides that can be used as supplements in food for nutraceutical or health applications. The extraction of polar lipids naturally rich in PUFAs by enzymatic processes without organic solvent (controlled by pH-Stat method at laboratory and industrial scale), coupled with the production of 1 kDa salmon peptides by membrane filtration, allowed the formulation of nanocarriers. The physicochemical properties of the nanoliposomes (size, zeta potential, encapsulation efficiency) were measured, and the bioactivity of salmon hydrolysate peptides was assessed (antioxidant and antiradical activity: ABTS, ORAC, DPPH; iron metal chelation).
Examples of encapsulation of various molecules will be presented to illustrate the interest of these dual-functional vectors attributed to the composition of LC-PUFAs, as well as encapsulated bioactive substances (antioxidants, vitamins, calcein, curcumin, enzymes, peptides…), which have proven to have a beneficial or protective physiological effect against chronic diseases.
These valorization techniques through green processes could be of interest to some aquaculture farms to valorize co-products and/or to have vectors whose composition in peptides and lipids would adapt to the growth of the fry.
