Modified atmosphere packaging of flounder fillet: Modelling of package conditions and comparison of different flushing atmospheres for quality preservation

Modified atmosphere packaging (MAP) flushed in high CO2 concentration with high gas barrier layer is often applied to preserve fish at chilled temperatures. Dissolution of CO2 in fish product results in changes from the original CO2 concentration and volume of packages. Maintenance of the desired CO2 concentration under appropriate package volume is required for realising effectiveness in fish preservation and handling through distribution channel. In the present work, mathematical model for estimating package gas compositional changes along with volume decrease was developed by incorporating CO2 dissolution dynamics into gas mass balance equation, and it was then validated by 200 g flounder packages flushed with atmospheres of 30 or 60% CO2 and stored at 5°C. Then, the effect of different modified atmospheres (MAs) on preservation of the flounder fillets was examined for 100 g flounder packages stored at 10°C for 5 d. Package flushed with MA of CO2 60%/O2 30%/N2 10% was the best for preserving flounder fillet preservation, in terms of total aerobic bacteria inhibition and low volatile basic nitrogen content as major quality indexes.