Browsing by Author "Wahlgren, Saara"

Microbiological and sensory quality are the main attributes to estimate the shelf life of the broiler chicken meat. Both can be affected by MAP (modified atmosphere packaging). Even though there has been a lot of research on MAP, the same gas mixture might not work even for similar products. The first aim of this study was to determine the best possible gas mixture for the microbial and sensorial quality of the chicken fillets. Secondly, to find out if a pre-treatment affects the functionality of the MAP and if the packaging material influences gas stability. Three different kind of chicken breast fillets were used as samples: natural, slightly salted, and marinated. Each of the fillets were packed in five different gas mixtures (1–5) which were combinations of carbon dioxide (CO2) and nitrogen (N2). Samples were packed in two different packaging materials where one of them had a better gas barrier than the other. The samples were stored in cold room (5ºC) for 21 days. Microbiological measurements were carried out for four days and quality measurements for three days. Quality analyses measured the water holding capacity, pH, colour, smell, tenderness of the meat, packaging collapse and gas stability. According to our results we could not differentiate a gas mixture that would fit best for all differently pre-treated samples. Gas mixture (3) prolonged the shelf life only with natural fillets. Fillets packed to gas mixture (3) had lower pH, but higher drip and cooking losses. Higher CO2 content in the gas mixture was connected to greater packaging collapse. Gas mixtures (1), (4) and (5) maintained the quality characteristics best. Pre-treatment influenced the tenderness of the fillets, microbiological quality, and the gas composition. Packaging material had a slight effect on the gas composition but there was no significant difference at the end of the storage period.