Technological and nutritional advantages of mechanical separation process applied to three European aquacultured species

Recently, mechanical separation (MS) process has been applied on fish sector, however, its impact on fish quality is scarcely investigated. Aim of the present study was to compare the impact of mechanical separation with manual mincing applied on European sea bass, gilthead sea bream, and rainbow trout by evaluating physico-chemical properties and nutritional quality. MS process yield was found higher than the manual one when applied to sea bass, and sea bream (42, and 45g/100g, respectively against 39, and 40g/100g). Rainbow trout had the highest processing yield even if the high presence of residual on the drum (5g/100g) lead a lower MS yield than the manual processing. MS seemed to slightly increase water content in sea bream and trout (71.12, and 70.65g/100g, respectively against 68.05, and 68.11g/100g of fillets) and decrease minerals, especially in trout, which showed loss of Ca, Mg, Na, and P. Hopefully, lipid fraction of the three species remained unaltered, indeed no significant differences were found in the fatty acid composition of the products, and consequently for the calculated atherogenicity and thrombogenicity indexes. In sum, manufacturing of products by exploiting fish without altering the nutritional value of whole fish is a goal reached adopting mechanically separation process.