Control of microbial growth and rancidity in rabbit carcasses by modified atmosphere packaging

Half‐carcasses of rabbit packed under four different modified atmospheres (MA; A: 30% CO2 + 70% O2; B: 30% CO2 + 30% O2 + 40% N2; C: 40% CO2 + 60% N2; D: 80% CO2 + 20% O2) and stored at 1 °C over 20 days, were assessed in relation to bacteria (total viable counts (TVC), lactic acid bacteria (LAB), Enterobacteriaceae and Pseudomonas) and rancidity development as 2‐thiobarbituric acid reactive substances (TBARS). None of the MA tested produced mean counts greater than 5 log CFU cm−2 for TVC and LAB, or greater 2 log CFU cm−2 for Pseudomonas and Enterobacteriaceae. All MA showed an inhibitory effect on microbial growth, especially on growth of the spoilage bacteria Pseudomonas and Enterobacteriaceae. This inhibition was more relevant in atmospheres with higher CO2 concentrations (types C and D). Significant differences in rancidity levels between MA types (p < 0.01) were observed 10 days post‐packing. In general these values were higher in MA type A, which showed a significant increase in TBARS values (p < 0.05) over time.