Fish Burger Enriched by Olive Oil Industrial by-Product

Oil industry produces large volume of wastes, both solid and liquid, which represent a disposal and potentially environmental pollution problem. Nevertheless, they are also promising sources of compounds that can be recovered and used as valuable substances. The aim of this work is to exploit solid olive by-products, in particular dry olive paste flour (DOPF) coming from Coratina cultivar, to enrich fish burger and enhance its quality characteristics. The addition of olive by-products leads to an increase of the phenolic content and antioxidant activity of the enriched food product; however, this also involves a deterioration of its sensory quality. To balance the quality and sensory characteristics of the investigated food, the study has been organized in three subsequent phase: first, the quality value of DOPF in terms of phenolic compounds content and antioxidant activity, has been assessed; afterward, DOPF has been added to fish burger to enhance its quality characteristics and, finally, the formulation of DOPF loaded fish burger has been optimize in order to improve its sensory quality. Results recorded in this study suggested that the enriched burger with 10% of DOPF showed a considerably increase in aliquot of polyphenols and antioxidant activity, but it negatively influenced its sensory quality. Pre-treating DOPF by hydration/extraction with milk, significantly improved the burger sensory quality by reducing the concentration of bitter components such as polyphenols.