Patent Application
20080083750
A detailed description of some of the embodiments of this translation is given below to provide a better understanding hereof, with reference to the drawings attached hereto with illustrative, not limitative, purposes.
Characteristic details of this novel foodstuff thawing tray will be shown in the detailed description of the embodiment shown in the attached drawings, indicating the same parts thereof with the same reference signs.
Cavities 3 where Maki sushi is deposited have vertical slots 1 where Japanese chopsticks used to take the sushi rolls are introduced. Regarding the other cavities 5, they also have vertical slots 4 to hold other types of sushi.
Maki containing cavities have passages 2 and passages 6 for other types of sushi in order to allow for the microwave generated heat to enter each cavity.
In other aspects of our invention, in more detail, our invention consists of a package formed by a base, also called tray, and a cover conformed by a plastic film, both are low microwave generated heat absorbents, and which make these microwaves penetrate evenly, being distributed between the cover and the lower end of the tray.
The film is selected for its low heat absorbing qualities, and serves as a lid, and is thermally sealed around the tray edges prior to the air extraction. One advantage of this film is that it is easy for the end consumer to open and further does not contain any adhesive that could contaminate foodstuff.
The tray is made of CPET, which is extruded in sheets that are then subject to a high temperature thermoforming process, which once in the shape of a tray with its resistance to high temperatures provides an unquestionable advantage to avoid absorption of a great amount of heat while on the microwave run, which would cause the sushi to burn or cook, causing thus serious damage to the thawing process.
The film (cover) is a co-extrusion of the polyester resin whose chemical composition is polyethylene terepthalate which in contact with microwaves and during the brief period of time, in which we use it, does not absorb heat quantities that could damage the sushi's integrity by burning and cooking it. It is a biaxial polyester film with a thermosealed amorphous polyester ply, an excellent barrier for oxygen, carbon dioxide, and water, with high resistance to high and low temperatures, and microwave radiations do not interact with this polyester film.
This invention comprises another embodiment of the film, consisting of a film whose main ply is made of dual orientation polyester, but it further contains various plies laminated to such polyester, as follows:
It was then possible to determine that the two materials with the best performance to achieve thawing in a microwave oven, for foodstuff such as sushi, are CPET (tray) and polyester film (cover), with a higher or lower number of plies of the same or different materials.
This CPET made tray is thicker than the cover, and has a thermal treatment applied when the cavities where the components of the meal are to be placed, for example, for sushi, precooked rice, raw fish, and also raw vegetables.
In one of its embodiments, this tray may comprise a black dye in its materials in order to avoid interaction of ultraviolet light and the foodstuff.
Our CPET is extruded with a double structure of the same CPET material in order to increase rigidity and resistance to high temperatures (when subjected to microwaves for thawing), and increases its resistance to impacts when subjected to very low temperatures (minus 21° C.); this is temperature that preserves sushi in the tray.
This invention has been described with details enough so that those skilled in the art may reproduce it and get the results stated herein. However, any person skilled in the art of this present invention may do non-described modifications thereto but if the application of such modifications in a given structure or its manufacture process requires the subject matter included in the following claims, such structures shall be included in the scope of this invention.
