MX2008010133A - Pouch for steaming vegetables - Google Patents

Abstract

A flexible pouch for cooking a food item using microwave energy. The pouch includes a base configured to retain hot gases above atmospheric pressure within the pouch to heat and cook the food item when the package is exposed to microwave energy. The pouch also includes a cover comprising a sealant layer and a score layer. The score layer includes a weak portion which ruptures and vents the pouch at a predictable location when pressure within the pouch due to the hot gasses exceeds a predetermined pressure.

Description

Bag for cooking steamed vegetables Field of the invention The invention is generally related to microwave cooking, and more particularly relates to a system using a flexible bag containing and cooking a food product that regulates and maintains a high internal heat and pressure during the microwave cooking process.

Antecedent of the Invention It is generally desired to prepare the food products in a bag. This allows the food product to be handled hygienically without direct contact with the food and commonly reduces or eliminates the need to clean kitchen utensils. For example, it is known to boil a variety of foods including rice and pasta in net bags. In doing so, the net bag with rice or pasta is immersed in boiling water. After the food is cooked, the bag is extracted from the water. Then the bag acts as its own sieve while water drains from the food and leaves the bag through the spaces in the network.

The bags described above are not commonly used for certain types of foods such as vegetables or fish because cooking these types of food directly in the water can cause a loss of vitamins and color in these foods. Water can also cause a change in the structure of the product as well as the overall flavor of the product.

In response to these disadvantages caused by the direct exposure of certain foods to water during the cooking process, the process of "boiling in a bag" has been developed. The process "boil in a bag" is a closed bag that avoids contact between the food that is in the bag and the water along with the loss of vitamins and color described above. In addition, meals boiled in bags are usually pre-cooked dishes in a sauce that means they can not be placed directly in the water without any protective packaging. Said bags are very difficult to handle after boiling due to the heat given off because the boiling is kept in the bag and can cause burns to the consumer when the bag is opened to access the food.

In response to these disadvantages of the "boil in a bag" process described above, several types of disposable containers have been developed for use in heating or cooking food in microwave ovens. For example, U.S. Patent No. 4,961,944 to Matoba et al. Discloses a flexible bag for use in cooking frozen foods. The food is poured into the bag that is sealed and then frozen. The bag has a number of openings covered by an adhesive tape. The adhesive tape is removed before going to the microwave to provide a vent for the steam that is generated during the microwave cooking process.

Plastic containers having edges with pressure relief valves are also known as disclosed in Application PCT / CH98 / 00546. This application discloses the use of a container that has a tray and a rigid lid. The lid has a pressure release valve that opens and closes to maintain a predetermined pressure for the cooking pressure of fresh food in the container heated by a microwave. However, such packaging is relatively expensive and the life of fresh foods is relatively short.

In view of the present, there is a need for a low cost, low waste item and a method for steam cooking frozen food products without encountering the disadvantages inherent in prior art.

Extract of the Invention The invention generally includes a flexible bag for use in microwaves by heating frozen foods that allows the product to be steamed during preparation. The bag provides a predictable breathing location, and it is easily manipulated and opened when it is completely heated. More specifically, the invention includes a flexible bag for cooking a food article using the energy of the microwave. The bag includes a base configured to retain the hot gases on atmospheric pressure in the bag to heat and cook the food when the package is exposed to microwave energy. The bag also includes a lid that compresses a sealing layer and a layer of dots. The dot layer includes a weak part that breaks and ventilates the bag in a desired location when the pressure in the bag due to hot gases exceeds a certain pressure.

In an alternative embodiment, the invention includes a bagged food that includes a plurality of pieces of frozen food, a flexible bag having an inner surface containing the food, and an outer surface. The inner surface is defined by a base and a sealing layer. The base is configured to retain the hot gases on atmospheric pressure in the bag to heat and cook the food when the bag is exposed to microwave energy. The bag also includes a layer of dots disposed on the sealing layer. The dot layer includes a weak portion configured to rupture and vent the bag in a foreseeable location when the pressure inside the bag due to the hot gases exceeds a certain pressure.

In yet another embodiment, the invention includes a method for cooking a food article that uses microwave energy. The method comprises the steps of obtaining a bagged food having a plurality of frozen food pieces. The bag has an inner surface containing the food and an outer surface, characterized in that the inner surface is defined by a base and a sealing layer. The bag also includes a layer of dots disposed on the sealing layer. The dot layer includes a weak portion configured to break and vent the bag in a Predictable location when the pressure inside the bag due to hot gases exceeds a predetermined pressure.

The method also includes the step of cooking the food article with the steam and hot gases generated by heating the food with microwave energy during the first phase of a cooking process. During the first phase of the cooking process, the sealing layer expands to hold the increased volume of hot gases until the sealing layer forms a permeable membrane. At this point, a second phase of the cooking process begins.

In the second phase of the cooking process steam and hot gases are conserved in the bag through the base and the dot layer. Then, the bag breaks in the weak portion of the dot layer during a final phase of the cooking process.

During the final phase of the cooking process, the internal pressure of the bag exceeds the predetermined pressure required to break the dot layer in the weak portion to allow release of the excessive pressure. Then, the method includes the step of venting steam and hot gases through the permeable sealing layer and the weak portion of the sealing layer. Finally, the steam and hot gases are retained in the bag to complete the heating and cooking of the food item.

Brief description of the figures The invention can be more fully understood in consideration of the following specification of several embodiments of the invention in relation to the accompanying figures, in which: Figure 1 shows an isometric view of the bag of the present invention.

Figure 2 shows a top view of the bag of the present invention.

Figure 3 shows a lateral cross-sectional view of the bag of the present invention before the heating process.

Figure 4 shows a side cross-sectional view of the bag of the present invention during a first phase of the heating process.

Figure 5 shows a side cross-sectional view of the bag of the present invention during a second phase of the heating process.

Figure 6 shows a side cross-sectional view of the bag of the present invention during a final phase of the heating process.

Figure 7 shows a top view of the bag of the present invention during a final phase of the heating process.

Figure 8 shows an isometric view of the bag of the present invention in an open position.

Figure 9 shows an isometric view of an alternative embodiment of the bag of the present invention during a final phase of the heating process.

Figure 10 shows an isometric view of an alternative embodiment of the bag of the present invention in an open position.

While the invention is subject to several modifications and alternative forms, specifications of the same have been shown by way of example in the figures and will be described in detail. It will be understood, however, that the intention is not to limit the invention to particular embodiments described. On the contrary, the intention is to cover all the modifications, equivalents, and alternatives that lie within the spirit and scope of the invention as defined by the appended claims.

Detailed description of the preferred embodiment A flexible bag 10 according to the invention is shown in Figure 1. The bag 10 is generally defined by a base 12 and a cover 14. The base 12 includes a side wall 18 and a base 20. The side wall 18 extends upwards from the base 20, defining an interior 22 to contain the food item 24. The edge 26 extends radially outwardly relative to the side wall 18. As shown in Fig. 1 the base 12 generally forms a rectangular container , although a variety of shapes including, round, triangular, irregular, or flat could be used as long as it is within the scope of the invention. Base 12 can also be manufactured from a variety of materials. In one embodiment, base 12 is an integrally thermoformed plastic material, such as, for example, polyolefins (eg, polypropylene, polyethylene) blends of polyolefins, polystyrene, HIPS, or materials based on polyester-CPET resin, polypropylene foam, polyethylene, paper and laminations of paper with polypropylene, polyester, etc. In an alternative embodiment, base 12 can be manufactured using compression molding or injection molding techniques.

With reference to Fig 3., the details of the lid 14 will now be discussed. The lid 14 includes a point layer 28 and a sealant layer 30. In a preferred embodiment, the point layer 28 and the sealant layer 30 include a laminated film such as PET / PE.

The combination of the sealant layer 30 and the base 12 defines the interior 22. The point layer 28 is disposed against the sealant layer 30. In one embodiment, the point layer 28 is attached to the sealant layer 30 with adhesive. In another embodiment, the dot layer 28 can be thermally bonded to the sealant layer 30.

The dot layer 28 includes the point 16. The point 16 does not extend to the sealing layer 30 of the lid 14, resulting in a completely sealed bag containing the food 24.

In one embodiment, the point 16 extends from the edge 26 on one side of the bag 10 to another edge on an opposite side of the bag. The point 16 can be formed mechanically in a layer of points 28. In alternative embodiments, the point 16 can be formed thermally or chemically in a dot layer 28. By weakening the tensile strength of the dot layer 28 at point 16, point 16 provides a predictable break location in the dot layer 28. In another embodiment, the tensile strength of the point layer 28 at point 16 is half the tensile strength of the point layer 28 without the point 16. In a preferred embodiment the tensile strength of the point layer 28 measured up to approximately 17 lbs / in and the tensile strength of the dot layer 28 at point 16 measured approximately 7 lbs / in.

As shown in Fig. 3, the bottom 20 of the bag 10 is generally flat. A flat edge 20 generates a stable location of the bag 10 on a table, in the microwave oven, or on another flat surface. In an alternative embodiment, the bottom 12 can be concave upwardly or inwardly relative to the interior 22 of the bag 10 to increase the interaction of the microwave with the food items in the bag 10.

As shown in the figures, the side 18 is continuous, extending radially upwards and outwards from the bottom 20 until it ends at the edge 26. It should be recognized, however, that in a preferred embodiment, the components of the base 12 and the Top 14 are highly flexible and can form a variety of shapes.

With reference to FIGs 3-10, the details of the bag 10 will now be discussed. When a user wishes to heat the food 24, the excess material of the package (not shown) is separated from the bag 10 and the bag 10 is located in the microwave. The user then programs the microwave to heat a desired cooking time. Although the cooking time depends on a variety of factors including food quantity 24 and microwave energy. Typical cooking times range from about 1 minute to 10 minutes, preferably between 2 to 6 minutes and more preferably between about 3 to 5 minutes.

When the microwave begins the cooking process, the bag 10 generally comprises the transverse configuration shown in Fig 3. During a first phase of the cooking process, steam and hot gases are generated in the interior 22 of the bag. The bag then expands to support the excessive volume created by the formation of steam as shown in Fig. 4. When steam and hot gases are generated, the lid 14 begins to bend in an upward direction while the sealing layer 30 pushes against the dot layer 28.

When the continuous cooking process, the sealing layer 30 begins to stretch and deform to allow the increased volume in the interior 22 of the bag 10 due to the generation of additional steam. In a second phase of the cooking process shown in Fig. 5, the sealing layer 30 fractures to form a permeable membrane which allows the vapor to be vented through several openings 32. When the steam is initially vented through the openings 32 the sealing layer 30 can be separated from the layer of stitches forming one or more pockets 43. The formation of the pocket 34 increases the pressure in the stitch layer 16 causing deformation when the steam and hot gases are conserved in the bag a through the base and the dot layer.

During a final phase of the cooking process, the pressure inside the bag 10 exceeds a predetermined pressure which causes the bag to break into a weak portion of the dot layer 28 as shown in Fig. 6. Because the weakest portion of the dot layer is in the maca 16, the bag 10 will break at the resulting point in a foreseeable ventilation location near the end of the heating. In this configuration, the steam and hot gases are vented through the permeable sealing layer and the weak portion of the dot layer while the steam and hot gases are conserved in the bag to complete the heating and cooking of the food item. .

Once the cooking process is complete, the bag 10 is extracted from the microwave. In a preferred embodiment, the user removes the bag 10 from the microwave by taking the edge 26 on opposite sides of the bag 10. The edge 26 provides a convenient and intuitive location in the bag 10 for the user to maintain it. The location of the edge 26 in relation to the food 24 allows the edge 26 to cool at a relatively fast rate allowing the user to remove the bag 10 from the microwave without discomfort.

Fig. 7 illustrates a top view of the bag 10 after the cooking process is completed but before the food 24 is removed from the bag. In a preferred embodiment, point 16 remains identifiable. However, point 16 contains openings 36, 38, and 40 that allow steam and hot gases to escape from interior 22 of bag 10 during the cooking process. Although three openings 36, 38, and 40 are shown in Fig. 7 by way of illustration, it is important to note that any number of openings can be formed at point 16 while within the scope of the invention.

With reference to Fig., Removal of food 24 from bag 10 will now be discussed. The configuration of point 16 upon completion of the cooking process provides a natural location for the extraction of food 24. However, generally, openings 36, 38, and 40 need to be combined in a single opening 50 to facilitate easy removal of the food.

To create the opening 50, the user takes edge 26 at the locations transverse to point 16. When using one hand to take point 42 and another hand to take point 44, the user separates point 42 from 44. When the distance between the point 42 and the point 44 increases, the openings 36, 38 and 40 are They expand to form a single opening 50. This configuration also provides a convenient location for users to move away from the heat of any remaining vapor that may escape from the bag. At this point, the food 24 can be easily removed from the container.

It is important to recognize that the point 16 can be located in a variety of locations in the point layer 28 as long as it is within the scope of the invention. For example, in Figures 7 and 8, point 16 is located centrally at points 42 and 44. However, it may be desired to locate point 16 closer to point 44 to facilitate removal of large or enlarged food from bag 10. In a preferred embodiment, the bag 10 incorporates a material that is easily broken to allow the lid 14 to be removed from the base 12 without scissors or knife. This aspect of the invention also allows the removal of large articles from the bag 10.

With reference to Figures 9 and 10, an alternative embodiment of the bag 10 will now be discussed. Figure 9 shows two openings 52 and 54 that are formed in point 16 upon completion of the cooking process. Again, it is necessary to combine openings 52 and 54 in point 16 to create a 50 single opening to facilitate a simple extraction of some food products.

To create an opening 50, the user holds the handles 56 and 58. The handles 56 and 58 are located near the edge 26 in locations transverse to point 16. When using one hand to take the handle 56 and another hand to take the handle 58 , the user separates the handle 56 from the handle 58. When the distance between the handle 56 and the handle 58 increases, the openings 52 and 54 expand to form a single opening 50. This configuration also provides a convenient location for the users are away from the heat of any remaining steam that may leave the bag 10. At this point, the food 24 can be easily removed from the container.

In another embodiment, the bag 10 can essentially be formed of a lid 14. A point 16 is located in the lid 14 to provide a foreseeable ventilation location. This incorporation has the advantage of simplifying the manufacturing process since only a single material is used to make the bag 10.

Bag 10 can be used for a variety of food items including predominantly and individually frozen carbohydrate ingredients, predominantly and individually frozen vegetable ingredients, predominantly and individually frozen meat-based ingredients and combinations thereof, although a wide variety of food items can be used while that are within the scope of the invention.

Although the invention has been described with reference to preferred embodiments, average knowledge workers will recognize that changes can be made in form and detail without departing from the spirit and scope of the invention.

Claims (20)

1. A flexible bag for cooking a food item using microwave energy, the bag comprises: A base configured to keep hot gases on atmospheric pressure in the bag to heat and cook the food item; A lid comprising a sealing layer and a dot layer, characterized in that the dot layer includes a weak portion that breaks and ventilates the bag in a foreseeable location when the pressure in the bag due to hot gases exceeds a predetermined pressure.

2. The bag of claim 1, characterized in that the weak portion is formed mechanically in the dot layer.

3. The bag of claim 1, characterized in that the weak portion is laser marked in the dot layer.

4. The bag of claim 1, characterized in that the tensile strength of the dot layer is greater than the tensile strength of the sealing layer.

5. The bag of claim 4, characterized in that the sealing layer is fixed to the sealing layer with adhesive.

6. The bag of claim 1 further comprises a plurality of pieces of frozen food.

7. The bag of claim 6, characterized in that the food is selected from the group consisting of predominantly and individually frozen carbohydrate ingredients, predominantly and individually frozen vegetable ingredients, predominantly frozen and individually frozen meat ingredients and combinations thereof,

8. The bag of claim 6, characterized in that the plurality of pieces of the frozen food further comprises a frozen liquid.

9. The bag of claim 1, characterized in that the base is configured to preserve said liquid in the bag by heating.

10. The bag of claim 1, characterized in that said bag further comprises a plurality of handles to facilitate the opening of the bag.

11. A food bag that includes: a plurality of pieces of frozen food; a flexible bag having an inner surface containing the food and an outer surface, characterized in that the inner surface is defined by a base and a sealing layer, characterized in that the base is configured to keep the hot gases on atmospheric pressure in the bag for heat and cook the food when the bag is exposed to microwave energy; a second layer disposed over the sealing layer, the sealing layer has a weak portion configured to rupture and vent the bag in a foreseeable location when the pressure inside the bag due to the hot gases exceeds a predetermined pressure.

12. The food of claim 11, characterized in that the weak portion is laser marked in the dot layer.

13. The food of claim 11, characterized in that the weak portion is formed mechanically in the dot layer.

14. The food of claim 13, characterized in that the tensile strength of the dot layer at a location adjacent to the dot is greater than the tensile strength of the sealing layer.

15. The food of claim 14, characterized in that the tensile strength of the dot layer in the weak portion is greater than the tensile strength of the sealing layer.

16. The food of claim 15, characterized in that the dot layer is glued to the sealing layer.

17. The food of claim 16, characterized in that the food is selected from the group consisting of predominantly and individually frozen carbohydrate ingredients, predominantly and individually frozen vegetable ingredients, predominantly frozen and individually frozen meat ingredients and combinations thereof.

The food of claim 17, characterized in that the base is configured to retain said liquid in the bag until heated.

19. The food of claim 18, characterized in that the bag further comprises a plurality of handles to facilitate the opening of the bag.

20. A method for cooking a food article that uses microwave energy comprising the steps of: obtaining a bagged food comprising a plurality of pieces of frozen food, the bag has an inner surface containing the food and an outer surface, characterized in that the inner surface is defined by a base and a sealing layer, the bag further comprises a dot layer disposed on the sealing layer, the dot layer has a weak portion configured to break and vent the bag in a foreseeable location when the pressure inside the bag due to the hot gases exceeds a predetermined pressure; cooking the food article with steam and hot gases generated by heating the food article with microwave energy during a first phase of the cooking process, characterized in that the sealing layer expands to sustain the increased volume of the hot gases until the sealing layer forms a permeable membrane during a second phase of the cooking process, characterized in that said steam and hot gases are conserved in the bag by the base and the dot layer; breaking the bag in the weak portion of the dot layer during a final phase of the cooking process when the internal pressure of the bag exceeds the predetermined pressure to allow release of excessive pressure during a final stage of the cooking process; vent steam and hot gases through the permeable sealing layer and the weak portion of the dot layer; and keep the steam and hot gases in the bag to complete the heating and cooking of the food item.