Effects of gas atmosphere, storage temperature and time on the quality and shelf-life of sliced poultry sausage

The aim of the study was to determine the effect of modified atmosphere packaging (100% nitrogen or 70% nitrogen and 30% carbon dioxide), compared to air atmosphere packaging, on the quality and shelf-life of medium comminuted poultry meat sausage stored at temperatures of 1 +/- 1 degreesC and 7 +/- 1 degreesC. Basic chemical composition, malonaldehyde content, pH value, and colour by reflectance method were determined. Microbiological examination comprised: total count of psychrophilic aerobic bacteria, lactic acid bacteria count, yeasts and moulds total count, coliform bacteria, and anaerobic spore forming bacilli. Microbiological, chemical, and sensory quality of sliced poultry meat sausage was dependent on the composition of atmosphere used in the packaging and storage temperature. At both examined temperatures, the sliced sausage packaged with modified atmosphere containing nitrogen and carbon dioxide resulted in a lower count of psychrophilic aerobic bacteria, lower dynamics of changes in TBA number, and substantially lower rate of unfavourable changes of taste and odour, in comparison to sausage samples packaged with nitrogen only or with air atmosphere. The elevation of storage temperature from 1 +/- 1 degreesC to 7 +/- 1 degreesC resulted in a twice as large reduction of the shelf-life of sliced sausage packaged with the mixture of nitrogen and carbon dioxide. The replacement of 30% nitrogen with carbon dioxide in the packaging, in comparison with 100% nitrogen atmosphere, resulted in extension of product shelf-life at 1 +/- 1 degreesC temperature by I week. The experimental findings confirmed the effectiveness of 30% carbon dioxide content in the packaging in the reduction of chemical and microbiological changes that occur in perishable meat products at both studied storage temperatures.