Impact of Modern Oven Treatments on Lipid Oxidation and Vitamin E Content of Fillets from Sardine (Sardina pilchardus) at Different Reproductive Cycle Phase

Abstract: The beneficial effects of sardine consumption can be related to the presence of bioactivecompounds, such as vitamin E and !3 polyunsaturated fatty acids. In any case, the levels of thesecompounds in sardine fillet depend on different factors mainly related to the diet and reproductivecycle phase of the fish as well as the technological treatments carried out to cook the fillets. The aim ofthe present study is two-fold: first, to evaluate changes in the total fatty acid profile, lipid oxidation,and vitamin E content of raw fillets from sardine (Sardina pilchardus) at different reproductive cyclephases (pre-spawning, spawning, and post-spawning); and second, to highlight how these nutritionalprofiles are affected by three oven treatments (conventional, steam, and sous-vide). For this purpose,raw fish was grouped into pre-spawning, spawning, and post-spawning phases according to themesenteric fat frequency and the gonadosomatic index evaluation, and submitted to conventional(CO), steam (SO), and sous-vide (SV) baking. The ratio of EPA/DHA and vitamin E increased frompost-spawning to pre-spawning, to spawning. Considering the reproductive phases, baking affectedthe oxidative degree differently: a CO > SO SV impact was found in the worst scenario (postspawning),mitigated by vitamin E, to CO SO > SV in the best scenario (spawning). SV was thebest treatment with high values of vitamin E in pre-spawning individuals (110.1 mg/kg). This studyshows how vitamin E is correlated to the combined effect of endogenous and exogenous factors.