Shelf-life and safety studies on rainbow trout fillets packaged under modified atmospheres

The combined effect of various gas packaging atmospheres (air, vacuum and gas packaging), films of different oxygen transmission rate (OTR) and storage temperature (4 and 12°C) were investigated on the shelf-life and safety of flesh rainbow trout fillets.Preliminary studies were done to determine the optimum packaging atmospheres to maintain the bright pink color of trout packaged in a high gas barrier film. Both vacuum and gas packaging (85% CO2:15%N2) resulted in the longest shelf-life (~28 days) in terms of color at 4°C. Based on these optimum gas atmospheres for color, shelf-life studies were performed at both refrigerated and temperature abuse conditions (12°C).Challenges studies were also done with Listeria monocytogenes and Clostridium botulinum type E, two psychrotrophic pathogens of concern in modified atmosphere packaged (MAP) fish.Subsequent studies were done to determine the effect of various levels of headspace oxygen (0--100%, balance CO2) or film OTR on the time to toxicity in trout stored at 12°C. (Abstract shortened by UMI.