ReviewCarbon dioxide absorbers for food packaging applications

•Types of CO2 scavengers to maintain a desired MA were described.•Thermodynamics and kinetics of CO2 absorption characterising the absorber function.•Some application cases of CO2 absorber in food package were described.•Systematic package design with tailored CO2 balance among the components.

BackgroundAlthough CO2 gas is useful for the modified-atmosphere packaging of foods, excess CO2 accumulation in a package may be detrimental to the quality of the product and/or the integrity of the package, particularly in the case of CO2-producing foods, such as fermented foods and fresh produce. In those cases, including CO2 scavengers in food packages is beneficial for preserving the food quality and package integrity.Scope and ApproachThe common mechanisms that are exploited for CO2 absorption in food packages are chemical reactions and physical adsorption. The CO2 absorption capacity and absorption kinetics of chemical and physical absorbers were examined and reviewed with respect to their proper use in packages of CO2-producing foods. The applications of CO2 scavengers in food packages were examined in terms of the benefits achieved and their efficacy.Key Findings and ConclusionsThe CO2 production characteristics and desired atmospheric conditions of foods must be established and tuned to the thermodynamic and kinetic properties of CO2 absorbers sometimes in combination with the gas transfer behaviour of the package layer. The combined or synergistic use of CO2 scavengers with other active packaging tools may be the direction for further research improving food quality preservation.