Effect of high pressure treatments on smoked cod quality during refrigerated storage

The effect of high pressure (HP) treatments on microbiological, chemical, textural and sensory characteristics of vacuum-packaged cold-smoked cod refrigerated at 5 °C for 60 d was evaluated. HP at 400, 500 and 600 MPa for 5 and 10 min reduced microbial counts of smoked cod and delayed microbial growth during refrigerated storage. No differences in lipid oxidation estimated as thiobarbituric acid reactive substances (TBARS) were observed after pressurization and during refrigeration. Only tryptamine and spermine at very low levels were detected among biogenic amines in smoked cod. High pressure treatments induced a brighter appearance of smoked cod, with higher values of L∗ and b∗, whereas a∗ values decreased with pressurization. HP affected hardness and shear strength of smoked cod, with higher values after treatment, but differences with untreated smoked cod were attenuated during the storage period. No differences in overall appearance and odor of smoked cod were reported after sensory evaluation. The results obtained in the present work point to the usefulness of pressurization of smoked cod at 400 MPa for 10 min or 500 MPa for 5 min to obtain an acceptable product with extended shelf-life. HP might increase the safety and protect the product against possible pathogen contamination during processing.