Effect of Modified Atmosphere Packaging on Quality Preservation of Mackerel Fillets

In Korea, mackerel is the most preferred red fish commodity and has been increasingly consumed in chillstored fresh state rather than in frozen or salted fish. Modified atmosphere packaging (MAP) technology as a replacement of air with low O2 and high CO2 concentration gas was applied in this study to preserve its freshness. Four MAP conditions of CO2(60):O2(30):N2(10), CO2(60):O2(5):N2(35), CO2(60):O2(0):N2(40), and CO2(30):O2(0):N2(70) were compared in quality preservation effect with air package used as Control. Three hundred grams mackerel fillets packaged in gas barrier tray were stored for duration of 10 days at 5oC. Quality was assessed in total aerobic bacterial count, pH, total volatile basic nitrogen (TVB-N), thiobarbituric acid-reactive substances (TBARS), peroxide value (POV), texture, and surface color. High CO2 concentration MAPs (CO2(60):O2(30):N2(10), CO2(60):O2(5):N2(35), and CO2(60):O2(0): N2(40)) inhibited total aerobic bacteria growth in the fish fillets. MAPs of high CO2 concentration with O2 containment (CO2(60):O2(30):N2(10) and CO2(60):O2(5):N2(35)) showed a low TVB-N content through the storage. The treatments containing O2 above 20% (Control and CO2(60):O2(30):N2(10)) showed more accelerated increases in TBARS and POV than other treatments. The visual appearance was better for fillets in the packages of CO2(60):O2(5):N2(35), CO2(60): O2(0):N2(40), and CO2(30):O2(0):N2(70) than for those of other treatments. The MAPs of CO2(60):O2(5):N2(35) and CO2(60):O2(0):N2(40) are expected to be effective in keeping the freshness of mackerel fillets.