Does home cooking affect nutrient contents and retentions of farmed European sea bass?

Objective: to determine contents and true retentions of proximate and fatty acid composition of total lipids in the flesh of farmed European sea bass (Dicentrarchus labrax L.), whenever prepared with home-style cooking methods; to characterize the same matrices as to the response given to cooking by triacylglycerols and phospholipids. Methodology: ten freshly caught batches (20 fish each) of 15-to-16-month-old European sea bass (overall average weight ± s.e. = 312 ± 5 g) were obtained in late summer through mid autumn from an intensive commercial fish farm. Within batch, fish were randomly and evenly allotted to four treatment categories: raw, oven broiling (OB, dry heat), baking in Al foil (BF, moist heat), or microwaving (MW), each analytical sample being a composite paste prepared with all the fillets from each subsample of fish (i.e. treatment within batch). True retention values of nutrients were calculated within each batch using a single composite raw reference for the three cooking methods, as the only devisable solution for portion-size fish. Summary of the main results: yields were quite different among cooking techniques (OB: 14.9%, BF: 9.4%, MW: 11.6%), leading to a significant decrease in moisture and an increase in protein content, independently of method. Lipid content decreased by 17% and 13% following OB and MW, respectively, whereas no substantial variation emerged for BF. The fatty acid composition of total lipids was significantly, though only slightly, modified by cooking. The same held true for both the triacylglycerol and phospholipid fractions, the most remarkable cooking-induced variation being the decrease observed in the PUFA n-6 level of the latter. Conclusion: on the grounds of the nutrient retention data obtained for the three home cooking techniques, BF qualified as the method more able to preserve macro-nutrients and fatty acids in European sea bass flesh, when compared with OB and MW.