Microwave Packaging

Abstract

A container for heating a food product with microwave energy having a wavelength. The container can include a generally circular centerline having an axis, and a receptacle including a sidewall extending at least partially around a cavity. At least a portion of the cavity can extend along at least a portion of the centerline. The sidewall can include an inner edge and an outer edge each being spaced apart from the axis of the centerline for at least partially retaining the food product in the cavity in proximity to the centerline.

What is claimed is: 
     
         1 . A container for heating a food product with microwave energy comprising a wavelength, the container comprising:
 a generally circular centerline having an axis;   a receptacle comprising a sidewall extending at least partially around a cavity, at least a portion of the cavity extending along at least a portion of the centerline; and   a support element comprising a top panel having at least one opening at least partially receiving the receptacle;   the sidewall comprising an inner edge and an outer edge each being spaced apart from the axis of the centerline for at least partially retaining the food product in the cavity in proximity to the centerline.   
     
     
         2 . The container of  claim 1 , wherein the inner edge is generally circular and is generally concentric with the centerline. 
     
     
         3 . The container of  claim 2 , wherein the centerline has a first diameter that is generally equal to the wavelength of the microwave energy, and the inner edge has a second diameter that is generally equal to at least half the wavelength of the microwave energy. 
     
     
         4 . The container of  claim 3 , wherein the outer edge extends around an outer perimeter of the receptacle and is spaced apart from the inner edge by at least half the wavelength of the microwave energy. 
     
     
         5 . The container of  claim 1 , wherein the inner edge extends along an inner perimeter of the receptacle and at least partially around the axis of the centerline. 
     
     
         6 . The container of  claim 5 , wherein the outer edge extends along an outer perimeter of the receptacle and at least partially around the axis of the centerline. 
     
     
         7 . The container of  claim 5 , further comprising an inner receptacle disposed within the inner perimeter. 
     
     
         8 . The container of  claim 7 , wherein the centerline has a diameter that is generally equal to the wavelength of the microwave energy, and the inner receptacle is generally confined to within a quarter of the wavelength from the axis of the centerline. 
     
     
         9 . The container of  claim 8 , wherein the food product comprises a primary food item for being disposed in the cavity of the receptacle and a secondary food item for being disposed in a secondary container that is for being received in the inner receptacle, and the primary food item is for being exposed to relatively higher microwave energy in the cavity of the receptacle than the secondary food item in the inner receptacle. 
     
     
         10 . The container of  claim 9 , wherein the primary food item comprises a generally lossless dielectric material and the secondary food item comprises a dielectric material that is relatively lossy with respect to the generally lossless dielectric material. 
     
     
         11 . The container of  claim 7 , further comprising an inner flange extending inwardly from the inner edge, the inner flange at least partially defining the inner receptacle. 
     
     
         12 . The container of  claim 5 , further comprising an inner spacing feature at least partially defined by the inner edge. 
     
     
         13 . The container of  claim 1 , further comprising an inner flange extending from the inner edge and an outer flange extending from the outer edge. 
     
     
         14 . The container of  claim 13 , wherein the inner flange extends along an inner perimeter of the receptacle and the outer flange extends along an outer perimeter of the receptacle. 
     
     
         15 . The container of  claim 1 , wherein:
 the receptacle is a first receptacle, the sidewall is a first sidewall, and the cavity is a first cavity;   the container further comprises at least a second receptacle comprising a second sidewall extending at least partially around a second cavity, at least a portion of the second cavity extending along at least a portion of the centerline.   
     
     
         16 . The container of  claim 15 , wherein each of the first sidewall and the second side wall comprises an inner portion, an outer portion spaced apart from the inner portion, and an oblique portion extending from the respective inner portion to the respective outer portion. 
     
     
         17 . The container of  claim 16 , wherein the oblique portion of the first sidewall is disposed proximate to the oblique portion of the second sidewall. 
     
     
         18 . The container of  claim 16 , wherein the centerline has a diameter that is generally equal to the wavelength of the microwave energy, and, for each of the first sidewall and the second sidewall, the inner portion is spaced apart from the axis of the centerline by at least a quarter of the wavelength from the axis of the centerline. 
     
     
         19 . The container of  claim 18 , wherein, for each of the first sidewall and the second sidewall, the outer portion is spaced apart from the inner portion by generally less than half the wavelength of the microwave energy. 
     
     
         20 . The container of  claim 15 , wherein the at least one opening comprises a first opening at least partially receiving the first receptacle and a second opening at least partially receiving the second receptacle. 
     
     
         21 . The container of  claim 20 , wherein the first opening and the second opening of the support element at least partially retain the respective first receptacle and second receptacle so that each of the first cavity and the second cavity is at least partially disposed along at least a portion of the centerline. 
     
     
         22 . The container of  claim 20 , wherein the first receptacle comprises a first flange extending from the first sidewall and the second receptacle comprises a second flange extending from the second sidewall, and each of the first flange and the second flange engages the top panel of the support element to at least partially support the respective first receptacle and second receptacle. 
     
     
         23 . The container of  claim 1 , wherein the support element comprises two side panels foldably connected to the top panel and a base panel foldably connected to the two side panels. 
     
     
         24 . The container of  claim 1 , wherein the support element comprises paperboard. 
     
     
         25 . The container of  claim 1 , wherein the wavelength of the microwave energy is an average wavelength of the microwave energy, and the centerline has a diameter that is generally equal to the average wavelength of the microwave energy. 
     
     
         26 . The container of  claim 1 , wherein the wavelength of the microwave energy is an average wavelength of the microwave energy, and the cavity comprises a maximum width extending radially from the inner edge to the outer edge, the maximum width being generally equal to or less than half the average wavelength of the microwave energy. 
     
     
         27 . The container of  claim 26 , wherein the food product comprises a generally lossless dielectric material. 
     
     
         28 . A method of heating a food product, comprising:
 obtaining a container comprising a generally circular centerline having an axis, a receptacle comprising a sidewall extending at least partially around a cavity, a support element comprising a top panel having at least one opening, at least a portion of the cavity extending along at least a portion of the centerline, the sidewall comprising an inner edge and an outer edge each being spaced apart from the axis of the centerline for at least partially retaining the food product in the cavity in proximity to the centerline;   positioning at least a portion of the food product in the cavity;   positioning the receptacle in the at least one opening so the receptacle is at least partially received in the opening; and   exposing the container and the food product to microwave energy comprising a wavelength.   
     
     
         29 . The method of  claim 28 , wherein the inner edge is generally circular and is generally concentric with the centerline. 
     
     
         30 . The method of  claim 29 , wherein the centerline has a first diameter that is generally equal to the wavelength of the microwave energy, and the inner edge has a second diameter that is generally equal to at least half the wavelength of the microwave energy. 
     
     
         31 . The method of  claim 30 , wherein the outer edge extends around an outer perimeter of the receptacle and is spaced apart from the inner edge by at least half the wavelength of the microwave energy. 
     
     
         32 . The method of  claim 28 , wherein:
 the container further comprises an inner receptacle disposed within the inner perimeter, wherein:   the food product comprises a primary food item and a secondary food item, the positioning at least a portion of the food product comprises positioning the first food item in the cavity; and   the method further comprises disposing the secondary food item in a secondary container and positioning the secondary container to be at least partially received in the inner receptacle.   
     
     
         33 . The method of  claim 32 , wherein the centerline has a diameter that is generally equal to the wavelength of the microwave energy, and the inner receptacle is generally confined to within a quarter of the wavelength from the axis of the centerline, and the exposing the container and the food product to the microwave energy comprises producing the microwave energy having at least the wavelength so that the primary food item generally is exposed to a relatively higher intensity of the microwave energy in the cavity of the receptacle than the secondary food item is generally exposed to in the inner receptacle. 
     
     
         34 . The method of  claim 33 , wherein the primary food item comprises a generally lossless dielectric material and the secondary food item comprises a dielectric material that is relatively lossy with respect to the generally lossless dielectric material. 
     
     
         35 . The method of  claim 28 , wherein:
 the receptacle is a first receptacle, the sidewall is a first sidewall, and the cavity is a first cavity;   the container further comprises at least a second receptacle comprising a second sidewall extending at least partially around a second cavity, at least a portion of the second cavity extending along at least a portion of the centerline; and   the positioning at least a portion of the food product further comprises positioning at least a portion of the food product in the second cavity.   
     
     
         36 . The method of  claim 35 , wherein the at least one opening comprises a first opening at least partially receiving the first receptacle and a second opening at least partially receiving the second receptacle, the method further comprising at least partially removing at least one of the first receptacle and the second receptacle from the support element after the exposing the container and the food product to the microwave energy. 
     
     
         37 . The method of  claim 28 , wherein the wavelength of the microwave energy is an average wavelength of the microwave energy, and the centerline has a diameter that is generally equal to the average wavelength of the microwave energy. 
     
     
         38 . The method of  claim 37 , wherein the food product comprises a generally lossless dielectric material.