Abstract

Effects of pulsed electric fields (PEF: 1-2 kV/cm, 20 mu s) used alone and combined with carbon dioxide (CO2: 70%) and high hydrostatic pressure (HP: 150 MPa, 5 min) on the physicochemical properties and microbiological shelf life of coho salmon under pre- and post-rigor conditions were studied during refrigerated storage (25 days). The PEF + CO2 + HP treatments reduced color changes in pre-rigor more than in post-rigor salmon. Texture changes of pre- and post-rigor salmon differed between untreated and treated salmon. Combined treatments also effectively reduced the protease and lipase activity of pre-rigor salmon. Collagenase activity of post-rigor salmon remained low in all treatments. Principal component analysis showed a clear difference between pre- and postrigor states in the evaluated parameters; however, microbiological shelf life increased with PEF + CO2 regardless of the rigor condition. In conclusion, combined PEF, CO2, and HP treatments can improve salmon quality during refrigerated storage and thus extend its microbial shelf life. Industrial relevance: The current demand for processed seafood that is similar to fresh products has created a new area of development in non-thermal processing technologies. Refrigeration and freezing have been applied for many years to extend the shelf life of seafood products, but there is deterioration regardless of the preservation method. Therefore, the combination of non-thermal processing technologies (PEF + CO2 + HP) could be applied to a large variety of seafood industries. Seafood products could be treated by PEF combined with CO2 and HP to further evaluate quality attributes under different rigor conditions during chilled storage and estimate the shelf life of the processed product.