High Pressure Processing under Mild Conditions for Bacterial Mitigation and Shelf Life Extension of European Sea Bass Fillets

Abstract

High pressure is an industrially established food preservation process applied for the minimal processing or cold pasteurization of chilled, fresh, or ready-to-eat products. This study aimed to quantify the effectiveness of high pressure on the inactivation of spoilage microflora and the shelf life extension of European sea bass (Dicentrarchus labrax) fillets. Fish fillets were subjected to mild, high pressure conditions (100–400 MPa; 3–25 °C; 5–10 min) and then stored at 0.0 ± 0.2 °C. Their shelf life was evaluated in terms of their microbiological, physicochemical, and sensorial quality. The results indicated that a shelf life extension of 1–5 d at 0 °C was achieved when pressures of 100 MPa were applied, whereas higher pressures resulted in an up to 5-fold increase in the shelf life of the fillets, depending on the applied pressure and temperature. A high pressure treatment combined with vacuum packaging showed an additional effect on the shelf life extension of the fillets, increasing the shelf life by 4–12 d when compared to aerobically stored products. Moreover, the high pressure treatment prevented lipid oxidation throughout the storage period, indicating no formation of secondary lipid oxidation products. The estimated shelf life of the fish fillets based on their sensorial quality was in accordance with the estimation based on the microbiological data.

Keywords

• high pressure processing
• low temperature
• bacterial inactivation
• shelf life
• European sea bass