JP4448583B2 - Package for microwave oven and method for producing package with food - Google Patents

Description

【００４１】
表１から、実施例１〜５、９、参考例１〜３の食品入り包装体は仕上がり性が良好で、またそのまま電子レンジで再加熱しても、包装体が優れた保水性および濡れ戻り性を有するため、食味の低下がないことが示される。これに対して比較例１〜７では、保水性および濡れ戻り性が低く、食味が大きく低下した。
【００４２】
【発明の効果】
本発明の電子レンジ用包装体によれば、コンビニエンスストア等で売られているハンバーガー等の食品の包装体として使用し、該食品を包装したまま電子レンジなどで再加熱処理しても、食品から出る余分な水分や油によって食品の風味が損なわれることがなく、また生産性および外観的にも優れた包装体を得ることができ、安価に食品入り包装体を得ることができる。
【図面の簡単な説明】
【図１】本発明の一実施例を示す食品入り包装体の説明図であり、(A) はラップ式包装体、(B) はガゼット式包装体の説明図である。
【図２】本発明に用いられる成形シートの斜視図であり、(A) は側部がプリーツ状の丸形成形トレー、(B) は側部がプリーツ状の楕円形成形トレー、(C) はフランジ部を有する角形成形トレーの説明図である。
【符号の説明】
１…成形シート、２…外装袋、３…プリーツ、４…フランジ、５…食品（ハンバーガー、６…シール部、１０…食品入りラップ式包装体、１１…食品入りガセット式包装体。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a package for a microwave oven and a package for food, and more particularly suitable for storing hot dogs, hamburgers, etc. sold at convenience stores, etc. A microwave oven package that can prevent the flavor of the food from being damaged by excess moisture and oil from the food when reheated in the range, improves the productivity of the package with food, and has an excellent appearance. The present invention relates to a method for manufacturing a package containing food.
[0002]
[Prior art]
In general, hot docks, hamburgers, and the like sold at convenience stores and the like are placed in containers and sheets made of paper or plastic materials. These foods are reheated in a microwave oven for each container or sheet before eating, but when heated in a microwave oven, steam is generated inside, and this steam stays inside without escaping to the outside. There is a problem that the condensed water becomes condensed and the condensed water adheres to the surface of a hamburger or the like, so that the surface of the food becomes watery and the appearance of the food is deteriorated. Also, when the cooked food is put in a container while it is hot, there is a problem that the deliciousness of the food is impaired by the generated steam and condensed water.
[0003]
In order to improve the above problems, products using materials such as paper and resin have been proposed. For example, a method has been proposed in which tray products made of paper or resin are used, food is placed on these trays and cooked and heated (Japanese Utility Model Publication No. 62-185275, Japanese Patent Application Laid-Open No. 54-101450, No. 3-31834, JP-A-6-329142, JP-A-8-244857, etc.).
However, since these methods assume not only microwave heating but also direct heating by a heater, it is not assumed that a large amount of condensed water will be generated when cooking with dielectric heating in a microwave oven. However, there was a drawback that the condensed water accumulated in the lower part of the tray, especially when a resin tray was used. In addition, air-permeable paper trays have improved heat resistance and improved releasability and shape retention by coating with inorganic pigments and silicon processing. As a result, the air permeability of the tray became insufficient, and vapor was likely to condense on the tray surface. Further, paper powder easily generates paper dust and the like, and the possibility of contamination by the processing agent of the above treatment increases, so that the food container is not always satisfactory in terms of hygiene.
[0004]
Various types of microwave oven bags have been proposed. For example, a microwave oven bag in which an outer layer sheet having no liquid permeability and a non-woven fabric sheet for preventing condensation has been proposed (Japanese Utility Model Laid-Open No. 3-108671, Japanese Utility Model Laid-Open No. 6-25141, Japanese Utility Model Laid-Open No. 6-61089). Japanese Laid-Open Patent Publication Nos. 3-200555 and 6-35164). These bags are made by integrating the nonwoven fabric and the outer layer sheet, or by integrating a water absorbing sheet between the outer layer sheet and the nonwoven fabric, and the excess water generated wets the surface of the food. It has been improved not to return.
However, in such an integrated structure, the water-absorbing sheet that absorbs water is integrated with the outer layer sheet, thereby reducing the gaps that retain the condensed water, substantially impairing the water-absorbing performance, and sufficient condensation. The prevention function was not obtained. Moreover, after bonding an outer layer sheet | seat and a nonwoven fabric, the operation | work which makes a bag structure and puts food into a bag after that is required, The price increase of the packaging bag and the food in a bag has arisen.
[0005]
[Problems to be solved by the invention]
The object of the present invention is to improve the above-mentioned drawbacks, reduce the dew condensation water generated when food such as a hamburger is reheated in a microwave oven, and to reduce the wetness of the food. Also, the bag structure and food using the same It is an object of the present invention to provide a microwave oven packaging body and a method for producing a food-containing packaging body that can improve the productivity of the product and that are hygienic and excellent in appearance.
[0006]
[Means for Solving the Problems]
The invention claimed in the present application is as follows.
(1)Made of liquid-impervious exterior sheetThe outer bag and the food inserted into the outer bag are placed.Of stamped molding traysA package,The basis weight of the exterior sheet is 10 to 100 g / m ² The thickness is 0.01-1 mm,AboveMolded trayBut independent of the outer bag, Average fineness 1.0-20 denier, basis weight 30-150g / m ² , Bulk density 0.05-0.15 g / cm ^Three Made of polyolefin fiberA package for a microwave oven, which is a sheet for preventing condensation formed of a nonwoven fabric.
(2)The microwave oven package according to (1), wherein the molding tray is obtained by embossing into a shape corresponding to the shape of food.
(3)Average fineness 1.0 ~ 20 denier, basis weight 30 ~ 150g / m ² , Bulk density 0.05-0.15 g / cm ^Three The main component is composed of polyolefin fiberMade of non-woven fabricOf molded trays embossed into shapes corresponding to the shape of foodPlace food on top of theMolded trayAnd foodThe basis weight is 10 to 100 g / m ² , Thickness is 0.01-1mm, liquid-imperviousIt is characterized by wrapping with an exterior sheet (1) For microwave oven as describedA method for manufacturing a package.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail.
The packaging body for microwave ovens in this invention has an exterior bag and the shaping | molding sheet | seat inserted in this exterior bag for mounting the foodstuff.
The outer bag used in the present invention is a liquid-impervious outer sheet that can prevent excessive oil and moisture generated inside when the food is wrapped and heated in a microwave oven. . As an exterior sheet, taking out food that has been heated by heating in a microwave oven, or taking care to prevent burns when wrapped in a sheet as it is, heat is not easily transmitted, and oil and moisture are outside the bag. Those that are difficult to bleed out are preferred. In addition, when used for refrigerated storage for several months, such as when used for refrigerated foods such as frozen foods, the exterior sheet is preferably a film material with low oxygen permeability in order to prevent the food from being oxidized and deteriorated. On the other hand, food bags designed to be eaten in a few days do not need to worry about oxygen permeability.
[0008]
In the present invention, liquid-impervious means that in a package containing food, excess oil or water discharged from the food does not ooze out or leak out of the sheet. In addition, when reheating in a microwave oven or the like, it means that the condensed water of water vapor from food does not ooze out from the sheet-like part that forms the outer bag. In any case, the molded sheet made of a nonwoven fabric made of a thermoplastic resin having a dew condensation preventing function in the present invention is liquid-permeable to the molded sheet. A liquid-impervious exterior sheet is used so that excess oil and moisture do not come out.
Examples of such exterior sheets include papers, sheets of paper coated with polyethylene, polypropylene resin, etc., synthetic resin films such as polypropylene, polyethylene, polyester, polyamide, polyvinyl alcohol, and foamed resins such as these resins and polystyrene. Examples thereof include a sheet having moisture permeability and waterproof properties such as a sheet, a nonwoven fabric obtained by a flash spinning method, and a microporous film.
[0009]
In addition, when it is assumed that food is put in a package and sold at a convenience store or the like, it is preferable that a part of the outer bag is transparent and the inner food is visible from the outside of the bag. It is preferable to use a transparent resin film, and it is preferable to form a window with a transparent resin film on a part of a sheet obtained by thinly coating polyethylene or polypropylene resin on paper.
In addition, the exterior sheet has a basis weight of 10 to 100 g / m from the viewpoint of preventing the appearance and shape of the package, tearing, mixing of dust, etc., or preventing the burns and keeping the food inside.²The thickness is preferably in the range of 0.01 to 1 mm.
Furthermore, the exterior sheet may have moisture permeability, and a part of the exterior sheet may be perforated. The moisture permeability of the exterior sheet is preferably adjusted as appropriate according to the amount of water generated for the purpose of expelling excess water vapor generated when heat-treated in a microwave oven to the outside of the sheet or bag.
[0010]
The molded sheet used in the present invention is a sheet for placing food, which is inserted into the exterior bag, and is a sheet for preventing condensation, which is made of a nonwoven fabric made of thermoplastic resin. This sheet for preventing condensation has the function of preventing condensation that retains the condensed water generated in the microwave oven and isolates the moisture and the food that is condensed in the outer bag or the like. Here, the dew condensation prevention function refers to a function that works to prevent the dew condensation water generated from the food from returning to the food as much as possible. Moreover, since the nonwoven fabric made from a thermoplastic resin is used for the shaping | molding sheet | seat, it is easy to form according to the shape of a foodstuff, and the outstanding rigidity and form retainability are obtained.
[0011]
Nonwoven fabric materials include, for example, monoolefin polymers such as ethylene, propylene, and butene, polyolefin resins mainly composed of these copolymers, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, nylon 6, and nylon 66. Further, polyamide resins such as nylon 12 and thermoplastic resins such as acrylic resins are used, and these are used alone or in combination. For example, a nonwoven fabric using the above-described resin alone may be used, or a composite nonwoven fabric obtained by mixing two or more types of fibers or a nonwoven fabric in which one fiber is formed of two or more types of resins. For example, a composite nonwoven fabric in which polyethylene fiber or polypropylene fiber and polyester fiber are mixed, a sheath core fiber made of a resin such as polyethylene, polypropylene, polyethylene terephthalate, or a nonwoven fabric using side-by-side fibers can be used.
[0012]
Among these, non-woven fabrics composed of monoolefin polymers such as propylene, ethylene, and butene and polyolefin fibers mainly composed of these copolymers are preferable. In the case of a sheath-core type composite fiber, the material of the surface corresponding to the food, that is, the material of the sheath may be polyolefin, and is not particularly limited to those entering the core. For example, a fiber whose sheath / core is polypropylene / polyester, polyethylene / polyester, polyethylene / polypropylene, or the like is used.
[0013]
By using polyolefin fibers having low hydrophilicity as the fibers constituting the nonwoven fabric, the food to be placed does not stick to the formed sheet, the peelability is improved, and the food can be easily taken out. In general, foods placed on molded sheets are starchy and cellulosic and highly hydrophilic ingredients such as bread, hamburgers, and rice. However, paraffin or silicon water repellent treatment has been carried out, but these water repellent agents may migrate to food and enter the human body. By using a polyolefin fiber having low hydrophilicity as the non-woven fiber, it is possible to improve the releasability from food without using a water repellent finish. When considering reheating in a microwave oven, polyolefin resin has a low dielectric constant and low dielectric loss compared to other polymers, so that the energy of microwave heating can be effectively added to food. It can be transmitted and heated efficiently.
[0014]
In the present invention, the function required of the molded sheet in contact with the food is to absorb and retain excess moisture and oil generated from the food inside the nonwoven fabric, isolate the absorbed moisture from the food, and further dew condensation on the food. The goal is to minimize water wetting back. In this sense, it is preferable that the nonwoven fabric itself maintains a bulky structure and has a large number of voids that retain excess moisture and oil inside the nonwoven fabric. For the above reasons, the basis weight of the nonwoven fabric used for the molded sheet is30-150 g / m ² The bulk density is 0.05 to 0.15 g / cm ^Three Is most preferred.
[0015]
Nonwoven fabric weight is 15g / m² If it is less than 1, the thickness of the molded sheet will be thin, the moisture and oil content retention capacity will be low, the moisture will return more, the food will be sticky at the bottom, the molded sheet will have insufficient rigidity, and the shape retention will be reduced There is a case. On the other hand, the basis weight is 300 g / m² If it exceeds 1, the thickness becomes thick, and the workability may decrease. The bulk density is 0.2 g / cm^ThreeWhen the amount exceeds 50%, the bulky property between the fibers of the nonwoven fabric is lost, and it becomes difficult to retain moisture and oil from the food. On the other hand, 0.01 g / cm^ThreeIf the ratio is less than 1, the production of the nonwoven fabric is substantially difficult, the strength is insufficient, and lint tends to be generated, and the workability and handleability may deteriorate.
[0016]
Furthermore, it is preferable that the average fineness of the fiber single yarn which comprises the nonwoven fabric used for a shaping | molding sheet is 0.5-50 denier, More preferably, it is 1.0-20 denier. If the fineness is less than 0.5 denier, the nonwoven fabric is densified, so the ability to retain excess moisture generated from foods is reduced, and moisture rewetting may increase. In addition, the contact area between the food and the molded sheet increases, and the food easily adheres to the molded sheet. Further, the strength of the nonwoven fabric is insufficient, the moldability is lowered, the rigidity of the molded sheet is insufficient, the sheet is broken due to friction or the like, the fibers are easily cut off and fall off, and this may become a source of food contamination. On the other hand, a nonwoven fabric having a fineness greater than 50 denier is substantially difficult to manufacture.
[0017]
The method for producing the nonwoven fabric is not particularly limited. For example, a general method such as a papermaking method, a method for producing a short fiber nonwoven fabric such as a card method, or a method for producing a long fiber nonwoven fabric such as a spunbond method may be adopted. it can. In addition, in the case of the nonwoven fabric obtained by the melt blow method, since the strength of each fiber is low and the resin crystallinity is low, it may be weak against external force such as rubbing. As a bonding method of the nonwoven fabric fibers, methods such as partial thermocompression bonding (embossing), bonding with an adhesive, ultrasonic welder bonding, partial hot air bonding, and needle punch bonding can be used. For food applications, the method of partial thermocompression bonding is most preferable from the viewpoint that abrasion strength, dust and lint are less likely to occur, and there is no excess binder resin or glue.
[0018]
The fibers forming the nonwoven fabric may be long fibers or short fibers, but long fibers are used from the viewpoint of contamination of food due to dropping off of the short fibers, sheet strength and wear durability. Is preferred. Further, the fiber may be not only a round cross section but also a deformed yarn such as a flat shape or a C shape, or a fiber that is crimped or the like. In consideration of the point of physically separating the food and the like absorbed from the moisture inside the sheet, it is preferable to use a deformed yarn or a crimp yarn.
In summary, the nonwoven fabric used in the molded sheet is a preferred embodiment of a long-fiber type spunbonded nonwoven fabric with good wear resistance and low waste yarns and the like mixed with food. A composite nonwoven fabric can also be used.
[0019]
The molded sheet is preferably used after being molded into a shape corresponding to the shape of the food. A known method can be employed for forming the formed sheet. For example, it can be obtained by cutting or punching a sheet to a desired size in advance and then embossing it into a tray shape. The punching and cutting may be performed at the same time as forming the tray. There is no particular limitation on the shape of the mold, and it can be a round shape, a square shape, a polygonal shape, etc., and its size and depth can be shaped according to the food. It can be formed into a pleated shape, or can have a shape having functionality and design with a flange. Especially when the shape of the food is not constant, the shape is irregular, or the size is large or small, the tray formed into a cup shape with pleats improves the shape followability when covering the outer bag with automatic production, It is preferable because productivity can be improved and the appearance can be improved.
[0020]
As the mold, a metal mold, a resin mold, a wooden mold, or the like is used, but a metal mold is more preferable in consideration of the degree of freedom of the mold and the degree of freedom of heating and pressurization during molding. The heating temperature, the heating time, and the holding time until release from the mold may be appropriately selected depending on the melting temperature, the crystallization temperature, the shape of the mold, and the like. For example, in the case of polyethylene terephthalate having a melting temperature of 260 ° C., the mold temperature is preferably maintained for several seconds in the range of 250 to 150 ° C. In the case of polypropylene having a melting temperature of 160 ° C., the mold temperature is preferably maintained for several seconds in the range of 150 to 100 ° C.
[0021]
The microwave oven package in the present invention has the above-described exterior bag and a molded sheet inserted into the exterior bag, and this molded sheet constitutes a part of the package in a state independent of the exterior bag. . In the present invention, the state where the molded sheet is independent of the exterior body means that the entire surface or part of the exterior bag and the molded sheet are not joined and integrated with each other by an adhesive or the like. A package containing food using such a microwave oven package is obtained, for example, by placing food on a molded sheet made of a nonwoven fabric made of thermoplastic resin and wrapping the molded sheet and the food in an exterior sheet. be able to. For example, food may be placed on a molded sheet formed in a tray shape and wrapped in an outer bag so as to wrap the whole, or food and a molded tray are simultaneously inserted into an outer bag formed in advance to open an opening. The part may be sealed. Since the packaging body is configured with the outer bag and the molded sheet being independent, not only can the labor of integrating the outer bag and the molded sheet be saved in advance, but the food can be transported on the molded sheet by automated transport. It saves the trouble of packaging and can be packaged hygienically.
[0022]
Moreover, since the exterior bag and the molded sheet are independent in terms of performance, when the microwave oven is heated, most of the condensation is formed on the surface of the exterior bag, thereby preventing the generation of condensed water on the molded sheet. Can do. Further, by using a water-repellent molded sheet, compared to the case of using a molded sheet with high water absorption such as paper, the dew condensation water generated in the outer bag is less likely to get back to the food side through the molded sheet. When a molded sheet having high water absorption, such as paper, is used, excess moisture condensed in the outer bag, that is, a place separated from the food, is absorbed by the molded sheet and easily returns to the food side.
[0023]
The package for a microwave oven in the present invention can be appropriately devised in an outer bag. For example, the shape of the outer bag may be a round shape or a flat bag, or a pillow shape bag or a bag with a gusset provided on the side and / or bottom. Further, it may be a box-shaped outer bag such as a square or round shape using cardboard or resin. It is more preferable to provide a window portion so that the food inside can be seen in these bags and boxes. Any form of window may be used, for example, a strip-shaped window, a form in which a circle or square window is provided at the center of the sheet, and a partially laminated inner sheet with an opaque inner layer sheet and a transparent outer layer sheet It is not carried out, but it can be set as the form which has a transparent part in the whole surface of other bags. In addition, when it is made into a bag shape, it may be provided with a minute hole or the like for discharging excess steam, and may be provided with a fastener or the like for improving the sealing property, and the food is delicious and easy to use. It is preferable to select a method and the like as appropriate.
[0024]
Also, it is preferable to provide an opening means such as a notch at the end of the package, or to provide an opening tape or the like for smooth opening.
The food-containing package of the present invention is reheated as it is in a microwave oven or the like, and then torn from a notch or the like, and the torn part is removed from other parts or bent, whereby a part of food such as a hamburger Can be exposed from the package, can be easily opened, and can be eaten without touching food directly by holding the portion previously formed into a bag, which is hygienic. In addition, it is preferable to design the molded sheet so that the molded sheet comes to the hand-held portion at this time because it will not be heated even if it is heated too much in the microwave oven or by hand.
[0025]
FIG. 1 is an explanatory view of a package containing food according to one embodiment of the present invention, in which (A) shows a wrap type package and (B) shows a gusset type package.
FIG. 2 is a perspective view of a molded sheet used in the present invention. (A) is a round-shaped tray with a pleated side, (B) is an oval-shaped tray with a pleated side, C) shows a angulated tray with a flange.
[0026]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples. In addition, the fabric weight and the bulk density of the nonwoven fabric in the examples were measured according to JIS-1906, and the thickness (measurement condition, peacock thickness type, pressurizer diameter 30 mm, load 0.49 KPa (5 gf / cm²)) Was measured, and the bulk density was determined by the following formula.
Bulk density (g / cm^Three) = Weight / Thickness
[0027]
Example 1
Polypropylene was melt-spun from the spinneret and pulled by air soccer to obtain 2.5 denier continuous long fibers. The fibers are spread and dispersed to produce a web by depositing on a web conveyor. The web is thermocompression bonded between an embossing roll and a flat roll with an embossed pattern interval of 4.5 mm at a crimping area ratio of 8%, and a basis weight of 50 g. / M²The long fiber nonwoven fabric was obtained. The resulting nonwoven fabric has a bulk density of 0.144 g / cm.^ThreeMet.
A tray was formed from this nonwoven fabric using a mold having the shape shown in FIG. Molding conditions are 1.96 × 10 at 150 ° C.^FivePa (2 kgf / cm²), And the substantial molding time (time during which pressure is applied in the mold, the same applies hereinafter) was 2 seconds.
The resulting molded tray is placed on a dedicated packaging line (a fully automatic rice ball packaging machine manufactured by Fuji Seiki; AKP-2400), a hamburger serving as a food is placed on the molded tray, and an exterior film (20 μm thick polypropylene-made protective film) is placed on the molded tray. A frosted film) was wrapped and the whole was wrapped as shown in FIG. 1 (A), and a sealing tape was applied to the lower part to make a package with food. Forty minutes of packaged foods were obtained per minute.
[0028]
Example 2
In Example 1, the basis weight is 30 g / m.²The bulk density is 0.124 g / cm^ThreeA molded tray was prepared in the same manner as in Example 1 except that a polypropylene non-woven fabric was used, and a food-containing package was obtained in the same manner.
Example 3
In Example 1, the basis weight is 130 g / m.²The bulk density is 0.165 g / cm^ThreeA non-woven fabric made of polypropylene of 3.92 × 10 6 under molding conditions of 150 ° C.^FivePa (4 kgf / cm²), Except that the substantial molding time was 2 seconds, a molding tray was prepared in the same manner as in Example 1, and a package containing food was obtained in the same manner.
[0029]
Example 4
In Example 1, the basis weight is 50 g / m.²Polypropylene long fiber nonwoven fabric (fiber diameter is 1.1 denier, bulk density is 0.120 g / cm^Three) Was used in the same manner as in Example 1 except that a package containing food was obtained.
Example 5
Polypropylene (sheath) / polyethylene terephthalate (core) sheath-core type 4 mm short fibers (fiber diameter 4.5 denier) are spread and dispersed by a card method to produce a web, The web was thermocompression bonded in the same manner as in Example 1 and 50 g / m.²The nonwoven fabric was made. The bulk density of the obtained nonwoven fabric is 0.077 g / cm.^ThreeMet. Using this nonwoven fabric, a molded tray was produced in the same manner as in Example 3, and a food-containing package was obtained in the same manner.
[0030]
Reference example 1
Polyethylene terephthalate was melt-spun from the spinneret and pulled by air soccer to obtain 2.2 denier continuous long fibers. The fibers are spread and dispersed, and are deposited on a web conveyor to produce a web. The web is thermocompressed between an embossing roll and a flat roll with an embossing pattern interval of 4.5 mm at a crimping area ratio of 8%, and a basis weight of 50 g / m²The long fiber nonwoven fabric was obtained. The resulting nonwoven fabric has a bulk density of 0.171 g / cm.^ThreeMet. A tray was formed from this nonwoven fabric using a mold having the shape shown in FIG. The molding conditions are 240 ° C. and 3.92 × 10^FivePa (4 kgf / cm²), And the substantial molding time was 2 seconds. The resulting molded tray was used in the same manner as in Example 1 to obtain a package with food.
Reference example 2
Reference example 130g / m²Non-woven fabric made of polyethylene terephthalate (fiber diameter is 1.5 denier and bulk density is 0.145 g / cm^ThreeExcept usingReference example 1A molded tray was prepared by the same method as above, and a food-containing package was obtained in the same manner.
[0031]
Reference example 3
Polyethylene terephthalate 4 mm long short fibers (fiber diameter: 3.0 denier) are spread and dispersed by the card method to produce a web on the web conveyor.Reference example 150g / m by thermocompression bonding in the same way²A non-woven fabric was obtained. The bulk density of the obtained nonwoven fabric is 0.091 g / cm.^ThreeMet. Using this nonwoven fabricReference example 1A molded tray was prepared by the same method as above, and a food-containing package was obtained in the same manner.
Example 9
The polypropylene nonwoven fabric obtained in Example 1 was reprocessed with a flat roll to obtain a bulk density of 0.250 g / cm.^ThreeThis was used to produce a molded tray by the same method as in Example 1 to obtain a package with food.
[0032]
Comparative Example 1
In Example 1, a package containing food was obtained in the same manner as in Example 1 except that a hamburger was directly wrapped in an exterior film without using a molded sheet.
Comparative Example 2
In Example 1, a package containing food was obtained in the same manner as in Example 1 except that a 50 μm film made of polypropylene was used as a molding tray.
[0033]
Comparative Example 3
In Example 1, water absorbent paper (Unicharm New Soflon FX, basis weight 22 g / m as a forming tray)²) Was used in the same manner as in Example 1 except that a package containing food was obtained.
Comparative Example 4
In Example 1, a package containing food was obtained in the same manner as in Example 1, except that a commercially available silicon-made paper tray (produced by Saran Wrap Sales Co., Ltd., trade name: Cook Par) was used as a forming tray.
[0034]
Comparative Example 5
The nonwoven fabric used in Example 1 was laminated integrally with the exterior film used in Example 1 and extrusion lamination (the resin for extrusion was 15 μm of polyethylene), and the obtained sheet was used in the same manner as in Example 1 to produce food. A packed package was obtained.
Comparative Example 6
Reference example 1The nonwoven fabric used inReference example 1The outer packaging film and the extrusion laminate used in 1 were integrally laminated (the resin for extrusion was 15 μm of polyethylene), and the package containing food was obtained in the same manner as in Example 1 using the obtained sheet.
Comparative Example 7
A hamburger was placed on the molding tray obtained in Example 1.
[0035]
<Test example>
Example1-5, 9, Reference Examples 1-3And the characteristic about the package with a foodstuff obtained by Comparative Examples 1-7 was evaluated by the following method, and the obtained result was shown in Table 1. Moreover, the taste evaluation after heating with a microwave oven and comprehensive evaluation were performed as follows, and the results are shown in Table 1.
(I) Finishing property of food-containing package The appearance of the obtained food-containing package was visually observed and evaluated according to the following criteria.
A: Appearance was good and the shape retention and rigidity of the molded sheet were sufficient. ○: Appearance was good, but the shape retention and rigidity of the molded sheet were slightly insufficient.
(Triangle | delta): The external appearance was a little bad, and the shape retention and rigidity of the molding sheet were a little insufficient.
X: Appearance was poor and product suitability was lacking.
[0036]
(ii) Condensation water rewetting
Put a quarter of a commercially available hamburger (about 50 g), beaker mouth (hole area 50 cm²), A sample (14 cm × 14 cm, the package is disassembled and the exterior sheet and the molded sheet are overlapped to form an evaluation sheet) is placed with the molded sheet side inside, and the mouth is stopped with a rubber band. Then irradiate in a 600 watt microwave for 2 minutes. Remove the sample from the microwave oven in a constant temperature and humidity room (20 ° C., 65% rh), remove the sheet after 5 minutes, and measure the weight with a balance. Next, a filter paper (with a basis weight of 120 g / m) is formed on the molded sheet surface of the sample.², A glass plate and a weight (1 kg) are placed thereon, and after 10 seconds, the weight of the filter paper and the sample is measured, and the following items are calculated. The measurement was performed 5 times for each sample, and the average was taken.
[0037]
A: Vapor generation adsorption amount
W₀: Sample weight (mg) before microwave irradiation
W₁: Sample weight after microwave irradiation (mg)
Vapor generation adsorption amount A (mg) = W₁-W₀
B: Wetting return amount and wetting return rate
R₀: Weight of the first filter paper
R₁: Weight of filter paper after 10 seconds with sample and filter paper overlapped
Wetting back amount B₁(Mg) = R₁-R₀
Wetting return rate B₂(%) = {(R₁-R₀) / A} × 100
C: Water retention amount and water retention rate of the sample
W₀: Sample weight before microwave irradiation
W_Three: Weight of sample after 10 seconds with sample and filter paper overlapped
Sample water retention C₁(Mg) = W_Three-W₀
Sample water retention C₂(%) = {(W_Three-W₀) / A} × 100
[0038]
(iii) Determination of taste
The package with food (with hamburger) was irradiated with a 600 watt microwave oven for 30 seconds, placed for 5 minutes, then taken out and eaten, and its taste was judged. The determination was made according to the following criteria in four stages. Each sample was tasted by 5 people and scored and averaged (scores ◎ 5, ４4, ２2, ０0).
A: There was moderate moisture and it was very delicious.
○: Although the bottom of the bread was slightly wet, it was delicious.
(Triangle | delta): Water | moisture content gathered at the bottom part of bread | pan, and it was not somewhat delicious.
X: Moisture gathered at the bottom of the bread and became crispy and was not delicious.
[0039]
(iv) Comprehensive judgment
The finishedness of the package containing food and the taste test were comprehensively judged by a monitor test. The determination was made according to the following criteria in four stages. Each sample was performed by 5 people, and each was assigned a score to obtain an average score (5 points, 4 points, 2 points, and 0 points).
◎: Good
◯: Decent
Δ: Not good
×: Bad
[0040]
[Table 1]

[0041]
From Table 1, Examples1-5, 9, Reference Examples 1-3It is shown that the packaged product with food of the present invention has a good finish, and even if it is reheated in a microwave oven as it is, the package has excellent water retention and wettability, so that the taste does not deteriorate. On the other hand, in Comparative Examples 1-7, water retention and wettability were low and the taste was greatly reduced.
[0042]
【The invention's effect】
According to the package for a microwave oven of the present invention, it can be used as a package for food such as a hamburger sold at a convenience store, etc. The excess moisture or oil that comes out does not impair the flavor of the food, and a package with excellent productivity and appearance can be obtained, and a package with food can be obtained at a low cost.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory view of a food-containing package showing one embodiment of the present invention, where (A) is a wrap-type package and (B) is an explanatory view of a gusset-type package.
FIGS. 2A and 2B are perspective views of a molded sheet used in the present invention, in which FIG. 2A is a round-formed tray with a pleated side, FIG. 2B is an oval-formed tray with a pleated side; FIG. 5 is an explanatory view of a angulated tray having a flange portion.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Molded sheet, 2 ... Exterior bag, 3 ... Pleat, 4 ... Flange, 5 ... Food (hamburger, 6 ... Seal part, 10 ... Wrapped package with food, 11 ... Gusseted package with food.

Claims (3)

A package of an outer bag made of a liquid- impervious outer sheet and a molded tray that is inserted into the outer bag and on which a food is placed, and has a basis weight of 10 to 100 g / m. ² , the thickness is 0.01 to 1 mm, the molding tray is independent of the outer bag , the average fineness 1.0 to 20 denier, the basis weight 30 to 150 g / m ² , the bulk density 0.05 to 0.15 g / cm ³ A packaging for microwave ovens, characterized in that it is a sheet for preventing condensation , comprising a nonwoven fabric composed of polyolefin fibers . The package for a microwave oven according to claim 1, wherein the molding tray is obtained by embossing into a shape corresponding to the shape of food. Average fineness 1.0 to 20 denier, basis weight 30 to 150 g / m ² , bulk density 0.05 to 0.15 g / cm ³ The main component consisting of nonwoven fabric composed of polyolefin-based fibers, placing the food on the molding trays embossed into a shape corresponding to the shape of the food, the molding trays and food, weight per unit area 10 to 100 g / m ^2, the production method according to claim 1 for a microwave oven packaging according to thickness and wherein the wrapping 0.01 to 1 mm, in non-deliverable-part outer sheet.

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