Conference lecture and academic presentation » Academic lecture
DEVELOPMENT OF A VOLUMETRIC METHOD TO DETERMINE CO2 SOLUBILITY INTO MUSCLE FOODS DURING MODIFIED ATMOSPHERE PACKAGING OR SOLUBLE GAS STABILISATION
WEFTA; Antwerp, 2005-09-19–2005-09-22
The object of this study was to develop a method to determine CO2 solubility into meat and fish packaged in flexible or semi-rigid packages during modified atmosphere (MA) packaging or soluble gas stabilization (SGS). Correctly adopted, MA packaging can extend the shelf-life and give better keeping quality for many foods. However, MA packaging of muscle foods with high water content are hampered by the need for a large gas to product volume ratio (g/p) when enhanced CO2 atmospheres are introduced, because of the high solubility of CO2 in water. A high g/p counteracts package collapse and ensures CO2 availability and thus, inhibition of microbial growth. The g/p is often as high as 2 or 3, and reducing this ratio would be economically beneficial for the industry. A novel way to reduce the package size is by using SGS, i.e. dissolving the CO2 into the product prior to packaging. In order to apply SGS correctly the amount of CO2 dissolved during treatment must be controlled and the solubility known. A volumetric method to determine CO2 dissolved in products packaged in semi-rigid packages was developed by applying the universal gas-law,Henrys law and Avogadro’s principle by submerging the package under water and measuring the lift force by a texture analyzer (Stable Micro Systems Ltd, TAXT plus, Godalming, UK). Temperated (274 and 280 K) distilled water (100 and 200 ml) packaged in CO2 (22.9 % and 72.4 %) balanced with N2 in polyethylene tray (HDPE-tray no 523, 415 ml Polimoon,Kristiansand, Norway) stored for 72 hours to reach equilibrium were used for method development and validation. Modelling of CO2 level, temperature and g/p ratio effect on CO2 solubility in water gave good correlation with literature data (r² = 99,1 %, prediction error =52,54 ppm). Results from MA packaged and SGS-treated (95% CO2 for 2 hours and 12 hours)non-respiring muscle food with low fat content measured with the developed method will be presented.