Gas mixtures approach to improve turkey meat shelf life under modified atmosphere packaging: the effect of carbon monoxide.

Gas mixtures with CO have been applied to beef and pork meat, but no data have been reported regarding their application to poultry meat. The aim of this study was to evaluate the effect of an anaerobic gas mixture with CO on the growth of spoilage flora, color, and lipid oxidation stability of turkey meat under modified atmosphere packaging (MAP) stored at 0°C. Sliced meat samples were individually packaged under aerobiosis (aerobic packaging) and in 4 different modified atmospheres containing different gas mixtures: MAP 1, 50% N(2) and 50% CO(2); MAP 2, 0.5% CO, 50% CO(2), and 49.5% N(2); MAP 3, 0.5% CO, 80% CO(2), and 19.5% N(2); and MAP 4, 100% N(2). All the samples were stored at 0 ± 1°C in the dark for 12 to 25 d. Meat samples packaged in aerobic packaging were analyzed for their microbial and physicochemical characteristics on d 0, 5, and 12 of storage, which was extended to 19 and 25 d when samples were under MAP. For meat packaged with MAP 3, the total mesophilic and psychrotrophic counts were significantly lower (P < 0.001) than those observed in condition MAP 1. The introduction of CO, added to a higher concentration of CO(2), inhibited microbial flora in general, with particular action on Brochothrix thermosphacta. In terms of microbial quality, the shelf life of turkey meat under the MAP study conditions was longer than that of meat in aerobic packaging (5 d): 12 d for mixture MAP 4, 19 d for MAP 1 and MAP 2, and 25 d for MAP 3. Only MAP 4 without CO(2) or CO prevented lipid oxidation of the meat. The presence of CO in anoxic gas mixtures with CO(2) for turkey meat under MAP was useful, giving the bright pink color preferred by consumers without leading to the appearance of undercooked meat.