JPH0238467B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to popcorn and easily openable containers therefor, and more particularly to popcorn and container combinations suitable for use in a microwave oven.

BACKGROUND OF THE INVENTION A variety of popcorn containers are known that allow corn kernels to be toasted and popped on or within a conventional cooking stove. One such container is described in US Pat. No. 3,110,233 to Mennen entitled "Metal Foil Forming Apparatus." However, these conventional containers are not suitable for use in microwave ovens, where metal foil is prohibited. Therefore, paper containers for popping corn in a microwave oven have been devised, one example of which is the U.S. patent issued to Brandburg et al.
No. 3973045, ``Popcorn packaging for popcorn using microwaves.'' However, these containers are specifically configured for microwave use;
Paper cannot be used in other types of ovens as it will burn.

However, currently known popcorn paper containers have several other significant drawbacks.
Paper containers soak up the shortening, or fat, contained in the popcorn and are therefore susceptible to soiling, and must be frozen to prevent the shortening from leaching to the outside of the paper container. When frozen before use, paper containers tend to transfer heat through the microwave floor, thus creating cold spots and reducing the efficiency of the popping action. Furthermore,
Known paper containers tend to allow steam to pass through, thus allowing steam to escape, reducing the temperature within the container and reducing the efficiency of the popping action, increasing the percentage of fruit that does not pop. On the other hand, if the container does not allow steam to pass through, the steam will remain inside the container, resulting in the disadvantage that the popped fruit will become moist within a very short time and will not be crispy. Paper also does not tear as easily as metal foil, making it difficult to open, especially when hot. Therefore, solving this problem requires an enclosure arrangement that is relatively complex and costly to fabricate.

The present invention provides a popcorn material and container combination suitable for use in a microwave oven that overcomes many of the problems described above. Generally, bags have a conventional upright configuration with a bottom panel, front and back panels, and gusseted side panels that are folded inwards. The edge of the bag opposite the bottom panel is foldable flat.
The bag is made of paper with an inner layer of impermeable material, preferably of polyester such as polyethylene terephthalate (PET). A coating, also preferably made of polyester, is applied to the inner layer to form a peelable seal along the top edge.

Preferably, the popcorn material within the bag includes corn kernels and cornstarch, which is solid at room temperature. The moisture content of corn kernels is at least about 11.5%, preferably
It is 13-14%. The peelable seal has sufficient strength to withstand the internal vapor pressure generated by this moisture content during at least half of the fruit popping process. Preferably, the bag is ventilated at its top seam to allow steam to escape before the fruit popping process is completed. It is preferable to allow steam to escape during at least the last 30 seconds of the fruit bursting process.

In a preferred embodiment of the invention, there is provided a central strip extending vertically along the bag between the gusseted sides where the front and back panels contact each other when the bag is folded flat. There is. A seal formed by heat and pressure at the top edge
The strength is lowest along the central strip where there is only a few layers of material. Therefore, the seal area corresponding to the central strip is where venting normally occurs. This ventilation action allows steam to escape,
This prevents the popped corn kernels from becoming too moist and crispy to chew.

Other features and advantages of the invention will be apparent from the following detailed description, which illustrates by way of example the principles of the invention and is taken in conjunction with the accompanying drawings, in which: FIG.

Popcorn bag 10 and its material 11 suitable for use in a microwave oven and constructed according to the invention
are shown in FIGS. 1 to 8 of the accompanying drawings.
The overall shape of the bag 10 is that of a conventional upright type, with a flat rectangular bottom panel 12, rectangular front and rear panels 14 and 16, and gusseted side panels 18 folded inwards. have

Material 11 is placed in the bag adjacent bottom panel 12. These materials 11 mainly consist of corn kernels, cornstarch, and salt.
Preferably they are all approximately the same size,
Almost all fruits burst uniformly within a short time frame, and the bursting time in the microwave depends on the size of the fruit. The bursting of the fruit is due to the moisture content, so
It is important that there is sufficient moisture. The moisture content should be at least 11.5% by weight of the fruit, better 13-14%, especially 13.5%. If the moisture content is too low, the burst fruit will be small and its density will be too high, making it impossible to obtain the desired fluffy feel.

Material 11 also includes a solid cutting at room temperature. Therefore, there is no need for refrigeration and the product has good shelf life. Animal fats are preferred as they tend to generate higher temperatures which are more favorable to the popping action.

Bag 10 is a single sheet of kraft paper 20 treated with a commercially available stain inhibitor (see Figure 5).
It is made up of an outer layer consisting of Inner layer 22 is a polyester layer such as polyethylene terephthalate, an example of which is O-L Mylar film available from DuPont. As a modification, the layer materials can be co-extruded to form polyethylene.
It may be a multilayer film having an outer layer of terephthalate and an intermediate layer of polycarbonate (such as Lexan manufactured by General Electric Co.) and ethylene vinyl alcohol. The preferred thickness of the inner layer 22 is about 0.5 to 1.0 mil and has a temperature of about 177 to 232 °C (350 °C) when exposed in a microwave oven.
It must be able to withstand temperatures of ~450°C without melting or contaminating the material 11 or imparting flavor. A coating (not separately shown in the drawings) sensitive to a combination of heat and pressure, commonly referred to as a heat seal coating, is applied to the exposed interior surface of inner layer 22. This coating is also polyethylene terephthalate, which is chemically similar to inner layer 22, but the coating is amorphous and sealable while the inner layer is crystalline.

All seams of bag 10 are sealed with a heat seal coating, and all seams have an additional back-up seal, except those extending along top edge 26 opposite bottom panel 12. The kraft paper 20 is not covered by an inner layer 22, but the surfaces of the paper are glued together. This is the 6th
As shown, this is accomplished along a seam 28 extending upwardly on the rear panel 16. There, the two ends of the kraft paper 20 are brought together, one end 30 is folded, and the other end is superimposed on the kraft paper on the one end side beyond the folded one end 30. As a result, a seal is formed in which the inner layers face each other in a portion close to the inside of the bag 10, and a seal in which the paper faces each other is formed on the outside thereof. The seal where the paper faces each other is the outer seal, and the seal where the inner layers face each other is the inner seal, so the entire inner surface of the bag that is exposed to the material 11 is covered by the inner layer 22, that is, the coating.
Material 11 does not come into direct contact with kraft paper 20. The inner layer 22 is impermeable to shortening;
Otherwise, the kraft paper 2 will be dry at room temperature.
0 can easily cause discoloration and unsanitary conditions, especially if not frozen. An oxygen barrier is also formed by the inner layer 22 so that material 1
1. The shelf life of item 1 increases. A back-up seal is a layer-to-layer seal that is not as strong as a paper-to-paper seal bonded to each other, especially due to the presence of internal vapor pressure generated during the bursting of the fruit. Even if a part should break, it is guaranteed that the material 11 will not come out.

When the bag 10 is prepared for use by a consumer, the bag is placed in a microwave oven 32 (as shown in FIG. 1).
2, and the bottom panel 12 of the bag is placed on the stove floor 34 as shown in FIG. When corn kernels absorb microwave energy,
The moisture contained in the fruit turns into steam and causes the fruit to burst, and the steam begins to fill the bag 10 in which the fruit is bursting, and the fruit reaches an expanded upright state as shown in FIG. 3 and then in FIG. 4. Become. During at least the initial stages of the bursting process, the lower part of the gusseted sides expands while the top edge 26 of the bag 10 remains closed against this pressure. Steam cannot escape from the bag 10 due to the inner layer 22. If the steam escapes prematurely, the volume of the product becomes too small and the popped corn becomes too dry and overcooked. Expansion of the bag 10 due to internal vapor pressure creates a vertical space of sufficient height above the bottom panel 12;
Enables free and unrestricted fruit popping action,
It should be noted that this reduces the number of fruits that do not burst.

As previously mentioned, the peelable sheet along the top edge 26 of the bag 10 is the inner layer-to-inner layer facing seam that is most easily separated as a result of the process in which it is treated with a heat seal coating. obtained as. Additionally, there is no back-up paper-to-paper seam along the top edge 26. Therefore, as pressure increases, the seam along the top edge 26 opens first. The strength of the top edge seal is such that the seam remains closed for at least the first half of the bursting time when the corn kernels have a moisture content of 11.5% or more by weight.

When the bag 10 is removed from the microwave oven 32, the top edge seal provides a convenient configuration for quickly opening the bag 10. As shown in Figure 7, bag 1
Grasp the diagonally opposite corners of 0 and pull them away. To fully open the bag 10, as shown in FIG. 8, the remaining two diagonally opposite corners can be pulled in the same way. This arrangement is very hygienic as the person opening the bag 10 does not have to touch the internal surfaces or material 11 at any point. Opening can be carried out when the bag 10 is hot, which is particularly advantageous if steam is still contained within the bag.

Although the seal along the top edge 26 can remain closed throughout the popping process, it is advantageous to open it late in the popping process, preferably before the last 30 seconds, to allow steam to escape. The bag 10 can be erected after the end of the popping process without any precautions, as would occur if the microwave oven 32 was equipped with a timer. If the bag 10 is left standing for several minutes with steam trapped inside, the popcorn will not be crispy and chewable, which is undesirable.

As shown in FIG. 6, the bag 10 has a central strip 3 where the front panel 14 and back panel 16 contact each other when the bag is folded flat.
It has 6. There are only two layers in the central strip 36, an inner layer and an outer layer, but there are more layers in the area of the gusseted sides 18. For example, there are six layers on one side where the seam 28 extends vertically above the bag 10 across one gusseted side. Since the seal along the top edge 26 is formed under pressure and heat, unless there are special circumstances that remove this effect, the seal will not adhere as strongly along the center strip 36 where the pressure is least. . Therefore,
The central portion of the top edge 26 is the primary vent for the seal, although in exceptional cases other portions of the top seal may initially vent. The location where ventilation is most likely to occur is indicated by the alpha-abbet "V" in Figure 6, which is close to the side where six layers of the bag 10 are present, and is the area where the width of the top layer is the narrowest. .

As can be seen from the foregoing description, the present invention provides a popcorn material and container combination that is convenient to use and suitable for use in a microwave oven.
The unique construction of the bag with a coating layer on the inside provides convenient and hygienic, easy-to-open features and automatic venting of steam.

While one particular form of the invention has been illustrated and described, it will be obvious that various changes may be made therein without departing from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.

[Brief explanation of drawings]

FIG. 1 is a front and plan view (partially cut away) of a bag according to the present invention and its contents placed in a microwave oven. Figure 2 is a cross-sectional view of the bag and contents along line 2-2 in Figure 1;
FIGS. 3 and 4 are partially cutaway perspective side views of the bag and its contents when the bursting process has started and when the bursting process is nearing completion, respectively. FIG. 5 is a cross-sectional view showing the material from which the bag is made; FIG. 6 is a plan view showing the top edge of the bag, with the thickness of each layer exaggerated to make the drawing easier to see. FIGS. 7 and 8 are plan views of the bag while it is being opened. 10...Popcorn bag, 11...Ingredients, 12
...Bottom panel, 14...Front panel, 16...
Rear panel, 18... Gusset-like side panel, 2
0... Outer layer of kraft paper, 22... Inner layer, 26...
...Top edge, 32...Microwave, 36...Central strip.

Claims (1)

[Scope of Claims] 1. A long-lasting combination of an easily openable upright bag for use in a microwave oven and a mixture of edible popcorn ingredients therein, wherein the bag has a bottom panel, a front panel, , a rear panel and an inwardly folded gusseted side panel, said panel being able to hold said bag when said gusseted side panel is closed and said front panel and rear panel are in contact with each other along a central strip. is configured to fold flat, and the bag defines a top edge having the thinnest thickness along the central strip, and the bag further includes an outer layer of paper forming an outer surface of the bag;
an inner impermeable layer forming the inner surface of the bag and a peelable seal formed along the top edge by a coating that is sensitive to a combination of heat and pressure; a peelable seal that retains steam until an internal pressure is reached, then opens in a central strip to allow steam to escape, and then opens along said top edge in response to being pulled at diagonally opposite corners; A material is disposed adjacent to the bottom panel and includes corn kernels having a moisture content of at least 11.5% by weight, and is thereby heated at a temperature of about 177-232°C (about 350-450°C). , a combination characterized in that an internal pressure sufficient to open the seal is generated along at least a portion of the top edge. 2. The combination according to claim 1, characterized in that the coating is polyester. 3. The combination according to claim 1, characterized in that the inner layer is polyethylene terephthalate. 4. The combination according to claim 1, wherein the shortening is a solid at room temperature. 5. The combination of claim 1, wherein the coating covers the entire interior surface of the bag exposed to the material. 6. Claim 1, wherein the moisture content of the corn is approximately 13 to 14% by weight.
Combinations listed in section. 7. said inner layer is polyethylene terephthalate and said coating is polyester, said coating covering the entire inner surface of said bag exposed to said material; said corn having a moisture content of about 13-14% by weight; A combination according to claim 1, characterized in that the shortening is a solid at room temperature. 8. A combination of an easily openable bag for use in a microwave oven and a mixture of edible popcorn material therein, comprising: the bottom panel, front panel, rear panel and a gusset folded inside of the bag; side panels configured to allow the bag to fold flat with the gusseted side panels closed and the front and back panels in contact with each other along a central strip; The bag forms a top edge opposite the bottom panel with the thinnest thickness along the central strip, and the bag is comprised of an outer layer of kraft paper and a polyethylene terephthalate layer with the entire exposed interior of the bag. formed along the apical edge by a non-permeable inner layer covering the surface and a coating sensitive to a combination of heat and pressure and capable of (1) responding to temperatures of approximately 177-232°C (approximately 350-450〓); (2) a peelable seal that confines the vapor until a predetermined internal pressure is reached and then opens in the central strip to allow the vapor to escape; and (2) then opens along the top edge in response to being pulled at diagonally opposed corners. the popcorn material is disposed adjacent to the bottom panel and comprises corn kernels and a cold, solid material, the corn kernels having a water content of about 13-14% by weight. amount, thereby causing the end of the bursting process to occur at the above-determined internal pressure.
A combination characterized by reaching 30 seconds ago.