Shelf-life Extension of Precooked Chicken Fillets by Modified Atmosphere Packaging

Abstract

The objective of this study was to determine the effects of modified atmosphere packaging (MAP) on qualities and shelf-life of chilled precooked chicken fillets. Precooked chicken fillets were packed in air (control) and under MAP conditions (20%CO₂+80%N₂, M1; 40%CO₂+60%N₂, M2 and 60%CO2+40%N₂, M3). All treatments were stored under refrigeration at 4±1°C. The results indicated that MAP conditions and storage time had no effect on water activity, moisture content, pH and surface color of all samples (P≥0.05). The precooked samples kept under MAP conditions showed significantly lower thiobarbituric acid (TBA) value as compared to that of the control sample (P<0.05). MAP was effective for inhibiting growth of total viable counts (TVC), lactic acid bacteria (LAB), Pseudomonas sp., and yeasts and molds. The higher CO₂ concentration, the higher inhibition of microbial records. Counts of E. coli and coliform were less than 2 log cfu/g whereas no Salmonella sp. and Listeria monocytogenes was detected in all chicken samples, irrespective of the packaging conditions throughout the storage period. Sensory analysis revealed that the precooked products were better preserved under MAP conditions. Physicochemical, microbiological and sensorial data indicated that the shelf-life of aerobically packaged precooked chicken fillets was around 5 days. MAP could extend product shelf-life to 35 days under M1 and at least 65 days under M2 and M3.