Technological watch

Convenient cuts of poultry products are of significant interest, but they are perishable products with a short shelf life. Modified atmosphere packaging (MAP) or the application of active packaging based on edible and biodegradable coatings could extend the shelf life of perishable foods. The aim of the present work was the kinetic modelling of the effect of MAP and active coatings with antimicrobial agents on the microbial growth and shelf life of chicken cuts. Broiler chicken thighs processed with pectin-based (2% w/w aqueous solution) edible coatings enriched with 1% extract of citrus bioflavonoids (flavomix) or 0.5% glucono-δ-lactone were stored under aerobic conditions at 0, 5 and 10 °C. Untreated thighs were also stored aerobically or in MAP (42.7% O2, 18.5% CO2). Quality evaluation was based on the growth of spoilage bacteria (TVC, Pseudomonas spp., Brochothrix thermosphacta), pH, colour, and sensory scoring. The tested quality indices were kinetically modelled and the Arrhenius model was used for the definition of the temperature dependence of the quality loss rates. Pseudomonas spp. dominated spoilage at all packaging and temperature conditions. Microbial growth correlated well with sensory degradation (Ea = 80–100 kJ/mol). Glucono-δ-lactone-enriched edible coatings resulted in 2 days of shelf life extension for chicken thighs at 5 °C. MAP and active, edible coatings with citrus extract showed a similar effect on the quality deterioration rate, and thus the shelf life of chicken cuts. Based on microbial growth, the shelf life was 6–7, 11, and 13 days at 5 °C for the control, EC-glu, MAP, and EC-flav samples, respectively (limit of acceptability = 107 cfu/g for TVC). The results of the study show the potential for using MAP or edible, active coatings to extend the shelf life and improve the commercial value of broiler chicken cuts.