Prepared meal product for microwave oven

Abstract

The present invention relates to a prepared meal product for being heated in a microwave oven and a method for heating said prepared meal product in a solid state microwave oven, wherein the prepared meal comprises a tray with separate areas and food items, characterized in that at least one area of the tray is more thermally insulated than at least one other area of said tray.

1 . A prepared meal product for being heated in a microwave oven, the prepared meal product comprising a microwavable tray and food items, wherein the microwavable tray has at least 2 separate areas, each area comprising at least one food item, at least one area of the microwavable tray is more thermally insulated than at least one other area of the microwavable tray. 
     
     
         2 . The prepared meal product according to  claim 1 , wherein the microwavable tray comprises a thermal insulation material in such a way as to providing more thermal insulation to at least one area of the microwavable tray than to at least one other area of the same microwavable tray. 
     
     
         3 . The prepared meal product according to  claim 1 , wherein the microwavable tray consists of a thermally insulating material in such a way as to provide more thermal insulation to at least one area of the microwavable tray than to at least one other area of the same microwavable tray. 
     
     
         4 . The prepared meal product according to  claim 2 , wherein the thermally insulating material providing more thermal insulation to the at least one area of the microwavable tray has a heat conductivity h=k/x of not more than half of the heat conductivity of the at least one other area of the same microwavable tray. 
     
     
         5 . The prepared meal product according to  claim 3 , wherein the thermal insulating material providing more thermal insulation to the at least one area of the microwavable tray has a heat conductivity h=k/x of not more than 25%, of the heat conductivity of the at least one other area of the same microwavable tray. 
     
     
         6 . The prepared meal product according to  claim 2 , wherein the thermally insulating material providing more thermal insulation to the at least one area of the microwavable tray has a thermal resistance value R of at least 0.01 m 2 K/W. 
     
     
         7 . The prepared meal product according to  claim 1 , wherein the thermal insulation material is in the form of one or several insulation layers. 
     
     
         8 . The prepared meal product according to  claim 1 , wherein the thermal insulation material is selected from the group consisting of cellulose, cork board, fiberglass, paper material, polycarbonate, polyester, polyethylene, polypropylene (PP), polystyrene (PS), polytetrafluorethylene (PTFE), polyvinylchloride (PVC), vinyl ester and combinations thereof. 
     
     
         9 . The prepared meal product according to  claim 1 , wherein the separate areas are separate compartments in the tray. 
     
     
         10 . The prepared meal product according to  claim 9 , wherein the tray has three or more separate compartments. 
     
     
         11 . The prepared meal product according to  claim 9 , wherein at least one of the compartments of the tray is shielded from microwaves in a microwave oven. 
     
     
         12 . The prepared meal product according to  claim 1 , wherein the food item is selected from the group consisting of meat, fish, vegetable, salad, potato, rice, pasta, sauces, gravies, desserts and a bakery product. 
     
     
         13 . The prepared meal product according to  claim 1 , wherein the tray comprising the food items is packaged in a plastic bag, a carton box and/or wrapped with a shrink film. 
     
     
         14 . The prepared meal product according to  claim 1 , wherein the prepared meal product is frozen or chilled. 
     
     
         15 . A method for heating a prepared meal product for being heated in a microwave oven, the prepared meal product comprising a microwavable tray and food items, wherein the microwavable tray has at least 2 separate areas, each area comprising at least one food item, at least one area of the microwavable tray is more thermally insulated than at least one other area of the microwavable tray in a solid state microwave oven, the method comprising the steps of:
 a) placing the prepared meal product into a cavity of a solid state microwave oven;   b) performing two or more radio frequency scans between a predetermined minimal and maximal frequency;   c) determining one or several radio frequencies having a higher power return loss when compared from one radio frequency scan to a previous radio frequency scan; and   d) heating the prepared meal product at a radio frequency determined in step c).   
     
     
         16 . The method according to  claim 15 , wherein the solid state microwave oven comprises an air fan circulating air in the cavity. 
     
     
         17 . The method according to  claim 15 , further comprising a step of heating the inside of the cavity of the solid state microwave oven with a heating source other than solid state microwaves. 
     
     
         18 . The method according to  claim 17 , wherein the heating source other than solid state microwaves is selected from the group consisting of an infrared emitter, a hot air inlet, a heating plate, and an electric grill. 
     
     
         19 . The method according to  claim 15 , wherein the radio frequency scan is from 902 to 928 MHz, or from 2400 to 2500 MHz. 
     
     
         20 . The method according to  claim 15 , wherein the heating in step d) is for at least 30 seconds.