Antioxidant effect of olive leaf powder on fresh Atlantic horse mackerel ( Trachurus trachurus) minced muscle.

Lipid oxidation is a very complex and important event causing quality loss of foods, especially those containing highly unsaturated fats. There is growing interest in replacing synthetic antioxidants in food by natural counterparts. Olive leaf is an abundant by-product of the olive oil industry. The aim of this study was to investigate the antioxidant capacity of olive leaf powder (OLP) in minced Atlantic horse mackerel stored at 4 °C over 3 days. OLP was introduced in the minced at concentrations of 0 (control), 1.5, 3.5, and 4.5%. OLP characterization showed high antioxidant capacity and fiber content. The addition of OLP significantly prevented and delayed minced fish oxidation over storage. The antioxidant effectiveness of OLP was concentration-dependent, as observed in all the parameters analyzed. The results showed OLP as a potential natural antioxidant for fish products. Practical applications Olive leaves are an important agrifood by-product produced worldwide. This by-product is valorized for the first time, as far as the authors are aware, as natural antioxidant in fish. Olive leaves are rich in polyphenols (principally oleuropein) and α-tocopherol. Consumers may benefit from this research as there is an increasing demand for natural ingredients, along with concern about the environmental effects of food production. The results of the present study suggest that olive leaf powder can be successfully employed as natural ingredient to prevent oxidation in chilled horse mackerel mince. This allows transforming this by-product stream into a commercially valuable antioxidant. [ABSTRACT FROM AUTHOR]