Food Engineering

FOOD PACKAGING: Package converts microwave into baking oven

April 16, 2003


Two versions of Graphic Packaging’s susceptor-equipped pie plates are in use: the Qwik Wave dish (left) for Pepperidge Farms pot pies, and the Micro-Rite package used by President’s Choice fruit pies.


Microwave ovens traditionally have been the enemies of baked goods, turning them soft and doughy and anything but golden brown. Graphic Packaging Corp. (GPC) devised microwave-friendly packaging that addresses those problems.

GPC’s susceptor-equipped Micro-Rite package debuted in Canadian supermarkets in November, allowing consumers to cook President’s Choice frozen fruit pies in 15 minutes. The pie plate is made of metallized polyester, which browns and crisps, and metallic foil that channels microwave energy to desired areas of oven and energy.

Metallized polyester, or susceptor, packaging reaches a temperature of 350°F almost instantly in a microwave. The metal that is used, along with the amount of reflectance, absorptance and transmittance that the package is allowed to provide, dictates the final temperature that is achieved and the amount of browning that occurs. For Pepperidge Farms’ Flaky Crust Pot Pie, excessive heat was burning the crust on the bottom of the tray while the center of the pie only achieved a temperature of about 70°F. Pepperidge Farms switched to GPC’s Qwik Wave pie dish last October. Unlike Micro-Rite, Qwik Wave does not have a top foil layer, and the susceptor pattern is demetallized in the flange area and the floor of the container, allowing energy to bypass the crust and heat the interior more thoroughly.

For more information:
Robb Hirschberg, Graphic Packaging Corp., 763-513-0478, hirschbergr@graphicpkg.com