Empleo de aceites esenciales para prolongar la vida útil de hamburguesas de salmón y algas ; Use of essential oils to extend the shelf-life of salmon and algae hamburgers

[EN] Today’s consumers seek food with excellent nutritional value, easy to prepare, without chemical additives, etc. Accordingly, the fish is a healthy food with high nutritional value. The hamburgers made from salmon and seaweeds (developed in a previous work) are a good alternative to promote fish consumption, because they are easy to prepare, do not contain bones or additives. On the other hand, essential oils are natural compounds with antioxidant and antimicrobial potential. The aim of this work was to evaluate the effect of different essential oils on the quality and shelf-life of fish and seaweed hamburgers during storage. Initially, different essential oil (EO) concentrations of thyme, cinnamon and oregano, were tested and a sensory analysis was carried out. Thyme and oregano EO were selected in a concentration of 0.05% (v/w). Three types of samples were prepared: salmon and seaweed hamburgers without EO (control sample), hamburgers with thyme EO and hamburgers with oregano EO, which were vacuum packaged and cold stored for 17 days. Physicochemical and microbiological analyses were carried out periodically throughout the storage. The addition of both EO did not have any effect on the evolution of the pH and the moisture. As for the total volatile basic nitrogen (TVB-N) and trimethylamine nitrogen (TMA-N), only the thyme EO managed to slightly slow down the increase of both parameters, but this inhibition would not be enough to increase significantly the hamburgers shelf- life, since all the samples reached the acceptance limit established for TVB-N at the same time. With regard to the oxidation of the samples, those which contained oregano EO and especially the samples which contained thyme EO showed a minor oxidation from the 10 day of storage, which demonstrates the antioxidant potential of these essential oils. Due to the vacuum packaging and the antioxidant capacity of seaweeds, the control samples did not show oxidation problems during the period of study. As for texture of the hamburgers, the ...