Correlation of Coextruded Barrier Sheet Properties With Packaged Food Quality

Abstract

Shelf life in food packaging is related to the sterilization process, the food product itself and to the type of barrier container. Heat sterilization to achieve various degrees of freedom from pathogenic micro organisms in food has been known and practiced for centuries. However, renewed interest has surfaced mainly due to "aseptic packaging"—the separate sterilization of food and the container using various methods and systems for forming/filling/sealing under sterile conditions. In order to prevent reinfection, the container must be made of a material resisting penetration of such organisms. The container also has to provide suitable resistance to penetration of the container by other substances. Thus aseptic packaging requires that containers be made of barrier material to resist such deleterious microorganisms and preserve the food. Correlating these plastic barrier materials to the required shelf life for packaged food quality is most economically accomplished through coextrusion.