Effects of High Pressure Treatment on Physicochemical Quality of Pre- and Post-Rigor Palm Ruff (Seriolella Violacea) Fillets

Abstract

8Fish and fish products are characterized for having a short shelf-life. Non-thermal 9 processing techniques such as High Hydrostatic Pressure (HHP) have increasingly been 10 employed to extend shelf-life of food products. The aim of this study was to evaluate 11 changes on flesh physicochemical spoilage parameters (pH, Total Volatile Bases (TVB-N), 12Trimethylamine (TMA), Thiobarbituric Acid (TBA) and color) of palm ruff (Seriolella 13 violacea) fillets in pre-and post-rigor conditions, subjected to two different HHP 14 conditions: 450 MPa and 550 MPa, for 3 and 4 min each. Unpressurized and pressurized 15 fillets were kept in chilled storage (4±1 °C) for 26 days to assess the effect of HHP on 16shelf-life. pH and TBA values increased after HHP treatment and with storage time for both 17 unpressurized and pressurized samples. This is attributable to pressure induced lipid 18 oxidation. Lightness (L*) values increased with pressure, where fish fillets became a 19 cooked appearance. TMA and TVB-N values decreased after HHP treatment compared to 20 the unpressurized samples, showing that HHP treatment is an efficient method to maintain 21 the quality of palm ruff fillets. There was no clear difference between pre-and post-rigor in 22 the parameters evaluated. 23Keywords: Palm ruff, high pressure, rigor stage, trimethylamine, color. 24 25 which is evidenced by a fast growing and a high fertility rate (Oliva et al., 1996). Therefore, 48Palm ruff rises as an alternative to the national fishing industry, currently focused on 49 salmon and mackerel farming, which in the last 10 years has suffered from huge 50 economical losses due to fish diseases (SERNAPESCA, 2008) and scarcity. 51 Fresh fish have a short shelf-life due to the rapid post-mortem flesh deterioration caused by 52 bacterial growth, autolytic enzymes activity (Dalgaard, 2000) protein degradation, lipid 53 oxidation and ATP decomposition, all of which accelerate the loss of freshness and quality 54 of fish (Ayala et al., 2010). These processes are delayed during chilled storage, however, 55 significant losses of sensory and nutritional values still occur (Reyes et al., 2015). All 56 muscle degradation processes occurring post-mortem start slowly during pre-rigor mortis 57 and spike after post-rigor has resolved (Cherét et al., 2005). Thus, prolonging the pre-rigor 58 state would retard flesh quality losses and increase shelf-life (Kristoffersen et al., 2007; Samples were taken at 0, 4, 8, 14 and 26 days. 79 80 HHP treatments 81Vacuum sealed fish fillets were placed in a cylindrical loading container at room 82 temperature and pressurized at 450 and 550 MPa for 3 and 4 min (hereafter 450/3, 450/4, 83 550/3, 550/4) at a rate of 17 MPa/s and room temperature (20.0±2.0 °C) in a high-pressure 84 unit (Avure Technol. Inc., Kent, WA, USA) using water as the pressure-transmitting 85 medium. After pressurization, samples were kept under chilled storage at 4±1 °C. The 86 experimental conditions were determined by a previous study to optimize the conditions of 87 HHP t...

Combined Treatments of High Hydrostatic Pressure and CO2 in Coho Salmon (Oncorhynchus kisutch): Effects on Enzyme Inactivation, Physicochemical Properties, and Microbial Shelf Life

“…The HHP treatment <200 MPa is not usually effective in extending salmon SL [26]; in the present study, there is no synergistic effect when HHP is combined with CO 2 to extend SL during storage. The HHP treatments on fish samples are commonly applied between 150 and 450 MPa and higher pressures are related to better microbial inactivation; they are also associated with significant changes in physicochemical and sensory properties [13,51]. The CO 2 inhibits aerobic bacterial growth (Pseudomonas spp.…”