Messenger - Vol. 1, No. 2, Page 6 Winter 1992 Seeking the consummate citrus container; James Paik is pursuing the perfect packaging for fresh fruit juices. Over the past year, Paik, an assistant professor of food science, has examined alternative constructions of juice cartons and the interaction of their interior packaging film with citrus products. Industry and consumers alike will benefit from improved packaging that maintains the quality and flavor of juice over time, he says. Under a grant from Westvaco, a packaging company, Paik and his students tested experimental cartons to determine which packaging materials were most effective in protecting the vitamins and taste of fresh juices. The juices were placed in cartons of different materials and laminates and then refrigerated. Students ran tests every few days to see which combinations provided the most protection in quality. After the tests were run, there were back-up taste tests. The study revealed that the way the cartons were sealed was as important as the materials used. "The best carton uses heat sealing conditions that provide the strongest barrier against oxygen," he said. "Cartons can be sealed at different temperatures and pressures and for different lengths of time." In another recent study, Paik tested the absorption and permeability of citrus flavor with polyethylene, polyester and ionomer packing films. Using inverse gas chromotography, he measured the interaction between the stationary phase (the packaging material) and the mobile flavor phase of the juice. Although all three polymers are used by industry for packing film, Paik found that polyester absorbed the least amount of product flavor.