The effects of modified atmosphere packaging on the physical, chemical and microbiological properties of rainbow trout (Oncorhynchus mykiss) fillets

Microbial (total bacteria count at 10°C, 25°C and 37°C, Pseudomonas, lactic acid bacteria, Enterobacteriacae, yeast and mold counts), physical (L, a and b values), chemical analysis [pH, total volatile bases nitrogen (TVB-N), lipid oxidation (TBARS)] and sensory analysis (general appearance and odour) of rainbow trout (Oncorynchus mykiss) fillets under in air (control), vacuum and different gas mixture conditions at 10°C and 4±1°C were determined. The gas mixtures evaluated were 100%CO2, 2.5%02 +7.5%N2+90%CO2 and 30%O2+30%N2+40%CO2. A demolition in sensory quality deterioration, bacterial growth and increases in TVB-N were reduced by modified atmosphere packaging (MAP). Lipid oxidation was lower in gas packages with vacuum and 100% C02 than in those 40% C02 both 10°C and 4±1°C. Compared with vacuum and air packaging it was determined that MAP extended the shelf life of fillets by various durations at 4±1°C. Keywords: Rainbow Trout, MAP, TVB-N, TBARS, Total Bacteria Count