MAP, product safety and nutritional quality F. Devlieghere and J. Debevere, Ghent University, Belgium and M I Gil, CEBAS-CSIC, Spain 11.1 Introduction Modified atmosphere packaging(MAP) may be defined as the enclosure of food products in gas-barrier materials, in which the gaseous environment has been changed(Young et al, 1988). Because of its substantial shelf-life extending effect, MAP has been one of the most significant and innovative growth areas in retail food packaging. The potential advantages and disadvantages of mAP have been presented by Farber (1991), Parry (1993) and Davies(1995) Whilst there is considerable information available regarding suitable mixtures for different food products, there is still a lack of scientific detail regarding many aspects relating to MAP. These include mechanism of action of carbon dioxide(CO2)on microorganisms safety of MAP packaged food products effect of MAP on the nutritional quality of packaged food products Current research and gaps in knowledge are discussed in the following sections 11.2 Carbon dioxide as an antimicrobial gas The gases that are applied in MAP today are basically O2, CO2 and N2. The last has no specific preservative effect but functions mainly as a filler gas to avoid the collapse that takes place when CO2 dissolves in the food product. CO because of its antimicrobial actrviduyced into the package, it is partly dissolved in11.1 Introduction Modified atmosphere packaging (MAP) may be defined as ‘the enclosure of food products in gas-barrier materials, in which the gaseous environment has been changed’ (Young et al., 1988). Because of its substantial shelf-life extending effect, MAP has been one of the most significant and innovative growth areas in retail food packaging. The potential advantages and disadvantages of MAP have been presented by Farber (1991), Parry (1993) and Davies (1995). Whilst there is considerable information available regarding suitable gas mixtures for different food products, there is still a lack of scientific detail regarding many aspects relating to MAP. These include: • mechanism of action of carbon dioxide (CO2) on microorganisms • safety of MAP packaged food products • effect of MAP on the nutritional quality of packaged food products. Current research and gaps in knowledge are discussed in the following sections. 11.2 Carbon dioxide as an antimicrobial gas The gases that are applied in MAP today are basically O2, CO2 and N2. The last has no specific preservative effect but functions mainly as a filler gas to avoid the collapse that takes place when CO2 dissolves in the food product. CO2, because of its antimicrobial activity, is the most important component in applied gas mixtures. When CO2 is introduced into the package, it is partly dissolved in 11 MAP, product safety and nutritional quality F. Devlieghere and J. Debevere, Ghent University, Belgium and M I Gil, CEBAS-CSIC, Spain