EFFECTS OF MODIFIED GAS ATMOSPHERE PACKAGING ON PORK LOIN COLOR, DISPLAY LIFE AND DRIP LOSS

Boneless loins front both sides of 20 pig carcasses were divided into five sections each and assigned equally to five packaging treatments: 100% CO2: 50% CO2/50% N-2; 25% CO2/75% N-2; 25% CO2/65% N-2/10% O-2 an d vacuum. Loin sections were packaged in bags of low O-2 permeability, then stored in darkness at 1 degrees C for up to 22 days. Retail chop s were cut from the sections and displayed in oxygen-permeable film un der light at 3 degrees C for 3 additional days. The O-2 concentrations in packages with nominally anoxic atmospheres were 0.1-0.4%. Sections stored in 25% CO2/65% N-2/10% O-2 had more surface greying and greeni ng, stronger off-odour and psychotropic counts after storage were more than one log(10) higher compared to sections from the other four trea tments. Displayed chops from sections stored in 25% CO2/65% N-2/10% O- 2 also had greying/greening at an outer layer of the chops. Off-odour of chops was most pronounced for treatments with 10% O-2 and vacuum. D rip loss from loin sections was highest for those in 100% CO2 (4.2%) a nd lowest for those in vacuum (3.2%). In conclusion, storage in CO2 or CO2/N-2 atmospheres benefitted the overall shelf life of pork. Copyri ght (C) 1996 Elsevier Science Ltd