JPH06165728A - Method for steam-cooling, and food container - Google Patents

Abstract

PURPOSE:To steam-cook efficiently without a steam pan into a good finish by a method wherein an objected to be cooked is packed with a container of which the whole or at least a part in contact with water is made of a material having set values specified in Japan Industrial Standard, and the outer lower side of the container is soaked in water and heated. CONSTITUTION:An object to be cooked is packed with a container of which the whole which comes into contact with water has at least 20sec of a value measured according to Japan Industrial Standard P8122-1976, Stoecktigt size degree testing method for paper, and at least a part which comes into contact with water has at most 800sec of a value (permeability) measured according to the same Standard P8117-1980, permeability test method for paper and board. The outer lower part of the container is soaked in water, which is heated for cooking. With that material, the water soaked part of the container is prevented from water-invasion, and at least a part thereof is permeated with steam, thus no water comes into the container, only steam can permeate it for steam- cooking. portion of the vessel is water permeable. Consequently, no liquid water does not enter into the inside of the vessel and boiled and heated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steaming method and a food container for steaming an object to be heated in the food manufacturing industry and other processes requiring steaming.

[0002]

2. Description of the Related Art Conventionally, as a method of steam heating with steam, there is a method of steaming and heating an object to be heated on a container-shaped object in the container using a steamer or a steamer. Was not in direct contact with liquid water.

[0003]

In the method of steam heating with steam, when steam, which is a gas, comes into contact with a heating object whose temperature is lower than that of the steam, the steam is cooled and tries to condense, and at that time a large amount of condensation heat is generated. It is well known that this is due to the heat transfer to the body, but in the conventional steam heating method, even if the atmospheric temperature of the space above the baby cage, that is, to the object to be heated is higher or lower than the boiling point of water, Both were prone to problems.

First, the case where the atmospheric temperature of the space from the water surface to the object to be heated is higher than the boiling point of water will be described. This is the case when the heat source reaches above the water surface, for example, when a flame when gas is used as the heat source reaches the outer wall of the steamer above the water surface.In such a case, the water surface The steam that tries to rise from the water surface toward the heated object is saturated steam when it is generated from the water surface, but it is overheated by being further heated on the way,
Since it becomes dry steam, when it reaches the heating target, it takes the moisture from the heating target and dries it,
It was often inconvenient.

Next, the case where the atmospheric temperature of the space from the water surface to the object to be heated is lower than the boiling point of water will be described. This is a case where the heat source is below the water surface and the thermal power is weak, and in such a case, when the water vapor that is going to rise from the water surface toward the heated object is generated from the water surface, Even though it is saturated steam, it tends to be cooled in the middle to contain a large amount of liquid water, and the amount of heat to be transmitted is also consumed. As a result, the heated object to be heated has a lot of moisture. However, this is inconvenient because it tends to be a problem and the time required for heating is long.

Further, in the conventional steam heating method, it is easy for the object to be heated to get wet due to a phenomenon called entrainment. That is, the bubbles generated when water is boiled try to jump out of the liquid field to the air field, but at the time of jumping, the bubbles burst and a small droplet with a diameter of 20 to 30 μm is blown to the upper air field by the force of the burst. When the bubbles move into the air field, they aggregate into large droplets with a diameter of several hundreds of μm or more, and easily pass through holes such as a shank with a diameter of several mm or more to be heated on the shank. I was wet.

[0007]

The present invention has been made in order to solve the above problems, and is characterized in that all the parts in contact with water have the Japanese Industrial Standard P812.
2-1976, the value (hereinafter referred to as sizing degree) measured by the method specified in Steckigt sizing degree test method for paper is 2
It is set to 0 seconds or more, and at least a part of the portion in contact with water is a value measured by the method defined in Japanese Industrial Standard P8117-1980, Air permeability test method for paper and paperboard (hereinafter referred to as air permeability) is 800 seconds. It includes a method of packaging an object to be heated in a container of the following materials, immersing the lower part of the outside of the container in water and boiling the water to steam the object to be heated, and a food container used for the method.

In the present invention, the object to be heated is packed in a container made of a material having a sizing degree of 20 seconds or more for all the parts in contact with water and an air permeability of 800 seconds or less for at least part of the parts in contact with water. Then, the lower part of the outside of the container is immersed in water and the steam generated by heating and boiling the water permeates the container wall to reach the inside of the container and further to the object to be steamed. Through, it is done.

First, the lower part outside the container in which the object to be heated is packaged is immersed in water. Then, the water tries to invade from the lower part outside the container in the part immersed in water, but the outside part of the container in the part soaked in water has some effect of suppressing the intrusion of water, and by the time the water reaches the inside of the container, It will take time. on the other hand,
When water is heated and boiled, the water turns into vapor, which is a gas, and exits from the upper surface of liquid water and tries to enter the inside of the container through the air-permeable portion or the opening of the outer wall of the container. inside that,
The permeable part of the water-immersed part has a sizing degree of 20 seconds or less, but it is permeable to water, so that the liquid water can reach the upper surface of the liquid water faster than it reaches the inside of the container. If the water is not heated and boiled so that the water becomes steam, the water enters the inside of the container and the object to be heated gets wet. On the other hand, if the water is heated and boiled so that the water on the upper surface of the liquid water becomes steam faster than the liquid water reaches the inside of the container, the liquid water does not enter the container, only the steam. When entering, the steam reaches the heating target inside the container, and if the heating target is lower in temperature than the steam, the steam transfers heat to the heating target. In the heat transfer in this case, the amount of latent heat released due to the condensation of water vapor is also transferred. That is, it is steamed and heated. By the way, the water vapor entering the container from a portion other than the portion of the outer wall of the container immersed in the water has the property that the water vapor proceeds from the lower side to the upper side, and the air has a specific gravity about twice that of the water vapor. If there is an air pocket lower than the inlet, it will not be possible to expel the accumulated air unless pressure is used, and since the air is a strong heat insulator,
When air is accumulated around the object to be heated, the efficiency of heat transfer to the object to be heated is extremely reduced, and it cannot be called steaming.

The object to be heated is steamed and heated through the above steps. As described above, the part of the container that is submerged in water must be such that the infiltration of water is suppressed to some extent. At least a part of the part soaked in must be permeable to a certain degree or more of water vapor as a gas, and no action will be taken unless water vapor is generated.

That is, the size of the water-immersed portion of the container is a certain value or more, the air permeability of at least a part of the water-immersed portion of the container is a certain value or less, and the water must be heated. It will not be possible.

Further, in the present invention, in addition to the above functions,
It has the effect of producing the great effects described below.
They remedy the drawbacks of conventional steamer and other methods.

First, the reason why the upper surface of the liquid water and the lower surface of the object to be heated are close to each other without making contact with each other will be described. Since the lower part of the outer side of the container in which the object to be heated is wrapped is immersed in water, the upper surface of the liquid water and the lower surface of the object to be heated are
Although they are not in contact with each other, they are close to each other, and the generated steam does not cool down or become overheated and dried by the time they reach the object to be heated. Also, it is less likely to get wet and dry. That is, in the conventional method of steaming and superheating, since the distance between the surface of the liquid water and the object to be heated is in the method using a bowl, when the ambient temperature above the liquid surface is lower than the boiling point of water, Before water vapor reaches the object to be heated, it is cooled to form dew drops, and becomes steam with a lot of dampness, resulting in wetting of the object to be heated and waste of heat, or the atmospheric temperature above the liquid surface is higher than the boiling point of water. If it is high, the steam will be in an overheated dry state before reaching the object to be heated, causing burning or drying of the object to be heated, whereas in the method of the present invention, there is almost no distance from the liquid surface to the object to be heated. Therefore, it is not easily affected by the atmosphere in the middle of the process, and the waste of heat amount, the moistening and the drying are not observed, and the heating time is shortened and the finished state is improved.

Further, in the case of using a baby bowl as in the conventional steam heating, there is a distance from the surface of the water vapor to the object to be heated, and there is no means for limiting the vapor diameter in the middle. Therefore, the water vapor diameter at the time of reaching the object to be heated tends to be large, whereas in the present invention, the water vapor is limited to a small size by passing through the pores of the porous material having a substantial pore diameter of about several μm or less. The water vapor that reaches the heating target is small because it is difficult for the steam diameter to reach the heating target because it is trying to enter the inside of the container and the heating target and water are close to each other. Since the surface area per unit weight is large, the heat transfer efficiency to the object to be heated is improved.

Further, since the object to be heated is packaged, there is no infiltration of droplets to the outside of the container due to the phenomenon of entrainment during boiling, so that the object is not wet with water. That is, the bubbles generated when water is boiled try to jump out of the liquid world into the air world, but at the moment of bursting, the bubbles burst and have a diameter of 2 mm.
Small droplets of 0 to 30 μm will be blown to the upper air field, and when the bubbles move to the air field, they will aggregate into large droplets with a diameter of several hundreds of μm or more. Hole diameter m
Since the liquid droplets easily pass through and the object to be heated gets wet with water because it is m or more, in the present invention, the container on the side in contact with water is made of a porous material having a substantial pore diameter of about several μm or less. Therefore, not to mention large droplets with a diameter of several hundred μm,
Even small droplets having a diameter of 20 to 30 μm will not pass through, and the object to be heated will not get wet with water. And this is especially convenient if we do not like water wetting.

The basic operation of the present invention and the effect thereof have been described above. The basic conditions therefor are the total size of the portion of the container which comes into contact with water and at least a part of the portion which comes into contact with water. The air permeability of is described below.

First, the size degree will be described. If the value is equal to or more than the boundary value that can be used for the purpose of the present invention and can be actually used, it is 20 seconds or more. When the sizing degree is less than 20 seconds, the water immediately before the container is immersed must be in a state of strong boiling, and the object to be heated must not be cold. When the sizing degree is less than 20 seconds, if the heating target object is cold or the boiling state of water is weak, the heating target object inside the container may be wet with water. When is set to 20 seconds or more,
Even if the boiling state of water is not strong and the object to be heated is cold, wetting of the object to be heated inside the container was not observed, so the practical size is 20 seconds or more. It seems better to have one.

The occurrence of water wetting when the sizing degree is less than 20 seconds is considered to be due to the following reason. That is,
When the container in which the object to be heated is packed is immersed in water, if the container and the object to be heated are cold, the boiling water will be cooled by immersing them and will be below the boiling point, generating a large amount of water vapor. On the other hand, when the size value is low, the water permeates quickly, so the time it takes for liquid water to reach the inside of the container will be It is said that the time to be sent and the time to boil vaporize the front of the water that has soaked into the container become earlier, so that the object to be heated gets wet with water.

On the other hand, when the sizing degree is set to 20 seconds, the boiling water is cooled by the container or the object to be heated, and even if the boiling of water, that is, the generation of a large amount of water vapor is stopped, the water is heated. If so, a large amount of water vapor generated and supplied by reboiling reaches the object to be heated and can be steamed and heated sooner than the water reaches the inside of the container.

Considering the variation of the material, it is better to set the size degree to 40 seconds or more, and it is effective that the size degree is actually 40 seconds.

Next, the air permeability will be described. If the value is below the boundary value that can be used in practice for the purpose of the present invention, it is 800 seconds or less. If the air permeability exceeds 800 seconds, drying or rupture of the container may be seen even if the temperature rise of the heating target is not expected, but if the air permeability is 800 seconds, heating Although the temperature of the object to be heated is slow, neither drying of the object to be heated nor rupture of the container was observed. Therefore, it is considered practical to set the air permeability to 800 seconds or less.

The inconvenience when the air permeability exceeds 800 seconds is considered to be due to the following reason. That is,
If the air permeability exceeds 800 seconds, the amount of water vapor that enters the inside of the container will be small, and the heating efficiency for the object to be heated will be poor, and the temperature increase inside the container will be conducted through the container. Mostly it is done by heat, and it can no longer be called steaming. Then, the surface of the object to be heated is dried, the temperature of only the surface is raised, or the gas in the sealed container expands or bursts due to the generation of the gas.

The air permeability of 100 seconds or less is considered to be more preferable because it is close to the finish of the conventional steaming method under appropriate conditions.

Next, two materials and forms of the container will be described.

First, the container may be rigid or flexible. However, considering the pressure during stack storage and transportation when not submerged in water, a solid one is more suitable for protecting the heating target inside the container, which is a box-shaped one or a dish. It can be embodied in a shape. However, when submerged in water, a bag-shaped container is often more convenient, and a bag-shaped container is mainly a flexible container.

The case where the container is made solid will be described. Not only the parts that come into contact with water, but the entire material may be paperboard or synthetic paperboard, but the structure for maintaining a firm form is plastics, and at least part of the parts that come into contact with water is May be paper, synthetic paper, rayon paper, cellophane paper, non-woven fabric, or a combination thereof having a sizing degree of 20 seconds or more and an air permeability of 800 seconds or less.
What is used for a part of this case may be flexible or solid.

Further, it is convenient to arrange a flexible portion in the joint portion of the solid portion so that it can be folded so that it does not take up a space for storage when not in use. In the case of a box, it is especially convenient to do so.

When the container has a box shape, not only a rectangular shape but also a cylindrical shape, a bowl shape, a spherical shape, a dome shape, or a dish-shaped side wall may be used. At that time, the heating efficiency may change depending on the position and size of the opening, regardless of whether the upper opening is provided or not.

Further, it may be in the shape of a dish, and in this case, if it has a shape that opens upward, it is easy and convenient to stack and store it as it is. Of course, it may be foldable, and may have a dish shape when opened. When using a dish-shaped object, it is floated on water like a boat, the size of the boat is 20 seconds or more, and the air permeability is 80.
It is suitable to dispose a material having a time of 0 second or less in a window plate shape. Further, a boat-shaped boat and a box-shaped boat may be combined to form a boat boat, or a box-shaped boat may be floated on water.

The case where the container is made flexible will be described. When it is made flexible, especially when it is made into a sheet, it is easy to wrap the object to be heated, for example wrapped in a tea squeezing shape, or after wrapping the contents, sealing or stopping with adhesive or tape, band etc. May be performed.
Also, it is easy to fold so it is convenient for storage. Further, for the purpose of protecting the object to be heated, that is, the contents, a solid material may be arranged in a part of the flexible material, or a combination thereof may be used. The flexible material may be paper, cellophane, rayon paper, synthetic paper, non-woven or plastic film or sheet, or a combination of the above.

The shape of the container made of a flexible material may be a bag shape. In this case, there is no need to wrap the contents like a sheet, and it is only necessary to put them in, which is convenient. In addition, it is easy to place the opening above the bag above the surface of the water. In this case, the opening may be closed or closed with a fastener such as a clip, tape, or adhesive, or adhesive or heat fusion. It may be sealed by coating with an agent or the like, and it can be easily treated so that it is difficult to put water in the bag. Of course, the bag usually floats on the water, so if you are careful, the water will not enter the bag. There are a method of making a bag with an adhesive resistant to hot water and a method of heat fusion. The heat fusion can be performed by applying a heat fusion agent, laminating a heat fusion layer, mixing a heat fusion substance into a bag material, mixing paper, or using the heat fusion substance alone. . In this case, if the heat-fusible substance is softened by water or softened at a temperature near the boiling point, bag breakage may occur due to use and water infiltration may occur, so care must be taken. . Therefore, the melting point and the softening point of the heat-fusible substance are better if they are higher than the boiling point of water, excluding the discussion on workability of heat-fusion. However, even with a heat-fusible substance having a melting point near the boiling point of water or a softening point considerably lower than the boiling point of water, such as an ionomer resin described later, if its property is utilized, it becomes convenient in the case of a sealing bag or the like. There are also things. That is, even if the opening when the contents are put in is not sealed by heat fusion, the ionomer resins applied to the openings are fused to each other by being heated by hot steam. It means that the opening of the bag may be sealed. In this case, it is necessary that the bag opening surface of the coated ionomer resin, which is the bag opening, is closely adhered to each other, but it is possible to fold the bag opening end and it is sealed. Things were confirmed. Instead of the ionomer resin, any other thermoplastic resin having a similar melting point or softening point may be used, and EEA resin, EVA resin, PVC resin, or the like may be used. In addition, when used in pressure cookers and vacuum cookers, even resins other than those having melting points and softening points near atmospheric pressure, those that have melting points or softening points near the boiling point at the pressure of the kettle The same phenomenon is possible if is selected. The coating, laminating, mixing, and mixing of the heat-fusible agent for heat-sealing may be performed on the entire surface or partially. In addition, when it is applied to the entire surface, it should be understood that the air permeability required in the present invention should not be impaired, but it is the one coated with an ionomer resin, and when the present invention is carried out under atmospheric pressure. It was considered that since the steaming was sufficiently steamed and heated, the loss of air permeability was small.

Secondly, any material may be used as long as it has the properties described in the claims of the present invention. However, practically, it is necessary to be inexpensive and have heat resistance, and from that point, it is best to use paper. The plastics material that can be used in the present invention is easily contracted by heat, and also contracted by hot water so as to be in close contact with or compressed by an object to be heated, which is likely to cause a problem. Further, since the plastics are melted by heat, they tend to be melted or damaged when they touch the inner wall of the pot or the like above the water surface, which has a temperature higher than the water temperature. Therefore, if plastics are used, it is necessary to consider that they are difficult to shrink or melt, or that they are placed in a portion that does not cause any trouble.

On the other hand, paper is easy to use because it does not shrink or melt due to heat. Further, since the paper is hydrophilic, even if it comes into contact with a heated inner wall of a pot or the like, it has a cooling effect of the water holding the paper, which makes the paper hard to burn. Also, even if dew drops occur during cooling after steam heating, it is difficult for the material with small hydrophilicity such as plastics to absorb the dew drops, which makes it easier for the object to be heated to get wet with water. Since has hydrophilicity, it absorbs dew drops and prevents the object to be heated from getting wet with water. The most important thing to note when using paper is the wet strength,
The value measured by the method specified in Japanese Industrial Standard P-8135, Wet Tensile Strength Test Method for Paper and Paperboard varies depending on the need, but it is 0.5 kg or more when a container is formed of paper alone. Seems more practical.

Considering shrinkage, melting, absorption of dew drops, etc., paper alone is good, but if the required levels can be achieved, it can be combined with plastics or inorganic substances such as mixed paper, coating, laminating and the like. In many cases, the composite is more suitable in consideration of the wet strength. Further, if thermoplastics are used for the inner surface of the container or the like, it is possible to seal the shape of the container and the opening by utilizing the heat-sealing property.

When compounding container materials, it is not appropriate to use a non-hydrophilic material around the object to be heated in the container for objects to be heated which do not like dew drop adhesion. When a non-hydrophilic material is used, dew droplets easily adhere to the object to be heated on the inner surface of the container. This is because in the case of a non-hydrophilic material, even if excess steam during heating can be discharged to the outside of the container from the opening or the air-permeable part of the material, it absorbs dew drops of water vapor in the container after heating is stopped. This is because the object to be heated easily gets wet with water. And
If a hydrophilic material is placed around the object to be heated, the dew droplets after the heating is stopped will be positively absorbed, and the object to be heated will not easily get wet with water. In this case, the hydrophilic material is a substance having a hydrophilic group such as cellulose or the like, which has a binding force with water particularly by hydrogen bond, or a substance which can utilize the binding force with water by ionic bond. It is a composition mainly composed of or that can utilize the capillary phenomenon. In order to exert a more water absorbing effect, the composition should be mainly composed of a substance having a hydrophilic group, and the capillary phenomenon should be utilized. Compared to the one that does not use the capillary phenomenon, the one that uses this capillary phenomenon has not only a high water absorption rate but also a good evaporation rate of water to the outside of the container after heating is stopped. It is effective. A typical example of this is paper, which seems to be the most suitable. If heat fusion is required, hydrophilic thermoplastics may be coated on paper, laminated, or mixed.

When the coating is performed for the purpose of heat fusion, it is necessary to partially coat the film or to prevent the air permeability from being impaired by forming a film even if it is coated on the front surface. In the case of coating on the entire surface, if granular close-packing coating can be performed, surface roughness, large surface area retention and pore retention are achieved, so it can be said that capillary water absorption can be used more effectively and is effective. Then, if it is applied to paper, it is applied to the surface irregularities and holes of the paper, so if it is applied thinly, it is possible to leave irregularities and holes that can utilize the capillary phenomenon. Therefore, it is necessary to select a coating method that does not coat the holes thickly or fill the holes by applying too much pressure. In that respect, a printing method in which the heat-fusible substance is adhered to the plate and then transferred to paper is suitable. Among them, the thickness and amount of the heat-fusible substance can be adjusted by the depth of the plate. The work method is appropriate. This method is convenient because partial coating and coating in which the thickness of the heat-sealing material changes depending on the portion are possible. When the heat-fusible substance is directly attached to the paper surface by dipping or coating, it is natural that it is difficult to produce a product with the coating thickness and coating amount adjusted unless the coating amount and thickness adjustment process is performed. However, it is better to avoid the method of scraping off the coating layer with a bar or knife after direct coating, or adjusting the thickness through a gap between rolls, because the pressure with a knife, bar, roll, etc. Since the heat-fusible substance is pushed into the holes of the paper by hanging it, the air permeability of the paper is impaired and the adjustment becomes difficult. Note that the application of heat fusion by applying a heat-fusible substance may be performed not only on paper, but also on non-woven fabrics, synthetic papers, etc. It is the content. Also, when printing or water-repellent treatment, the same care must be taken as in the case of applying the heat-fusible substance.

Many kinds of thermoplastics for imparting heat-sealing property can be considered, but it is necessary to select them in consideration of the purpose or actual use. The heat-sealing temperature should not be too high and the container forming operation should be inefficient, and the adhesion to the substrate should be sufficient. If the selection is based on low temperature heat sealability and adhesion to paper substrates, EAA. EEA. EMA. EMAA. EMMA.
It is believed that ethylene-based copolymer resins such as myonomer, EVA and EVOH, polyethylene and their compatibles are suitable. If the thermoplastic resin is placed on the entire surface or around the object to be heated, it is preferable that it has water absorption and water retention, and if considering the piercing strength and the strength against bending, myonomer resin seems to be the most suitable. .

When a bag or a box-shaped container is formed, it may be convenient to partially dispose a material such as transparent plastics in the upper position, if necessary. Because the material with good air permeability lacks transparency except for some parts such as cellophane, the contents cannot be seen when it is made into a bag or box, but the material with good transparency such as plastics is partly in the upper part. This is because you can see the contents if you distribute them.
However, since plastics with good transparency lack air permeability and hydrophilicity, except for cellophane, etc., the efficiency of steaming heating decreases and dew droplets tend to adhere, and the opening at the top of the container and the air permeability and hydrophilic material It may be necessary to devise the arrangement or the position and shape of the transparent portion. Note that cellophane may be arranged above. This is because cellophane has transparency, air permeability and hydrophilicity. However, since cellophane alone has a weak wet strength, it must be handled with care and reinforced.

The material and form of the container have been described above. Next, the points relating to the steaming heating efficiency in the present invention will be described. In the present invention, the water vapor needs to reach the object to be heated sufficiently, but heat cannot be sufficiently transferred to the object to be heated unless the air, which is a heat insulator, is driven out from the surroundings of the object to be heated. Therefore, when the object to be heated is placed in a place where the air does not escape sufficiently and water vapor does not reach directly, the object to be heated may be insufficiently heated. In the present invention, since water vapor normally enters the container from the water surface below the container, it is preferable to provide a gas permeable material part or an opening above the container as a vent for the air that is extruded by the water vapor and escapes. Where it is difficult to place it above, a breathable material or opening may be provided on the side of the container as long as the air is expelled. However, in that case, it is necessary to make sure that water does not enter.

In the present invention, the container may or may not be provided with a lid. When the container is a dish or a container without a lid, as the value of air permeability increases, the effect of water vapor is greater at the opening than at the bottom of the container. It is necessary to be careful because it may happen that the object to be heated gets wet or dry. In addition, the degree to which the water vapor uniformly covers the entire object to be heated decreases, and the heating uniformity may deteriorate.

On the other hand, a product provided with a lid, such as a bag or a container with a lid, has a good heat retaining property and is less likely to be affected by moist water vapor outside the container, so that the finish is also improved.
In addition, the presence of the lid makes it easier for vapor to stay in the entire container, and makes it easier to uniformly heat the entire object to be heated. However, when a lid is provided, if the air vent is not placed in an appropriate place, air will accumulate and the heat of the steam entering the container will not be sufficiently transmitted to the object to be heated due to the heat insulation of the air. Sometimes things happen. In this case, it is not necessary to provide a special air vent if the lid has a value that is equal to or lower than the air permeability of the part that is in contact with water and is an inlet for water vapor rather than water. . The simplest way is to use the same material as the part that is in contact with water and is the inlet for water vapor.

Next, the object to be heated will be described. Although it is not suitable for dry things that do not like moistness even a little,
It can be said that everything except heating is required for heating. Generally, the present invention is suitable for the production and heating of steamed foods such as Chinese steamed bun, chimaki, shimemai, steamed gyoza, etc., or kneaded products. The action and effect in this case are as described above.

Other foods include foods that are boiled in hot water in a water-impermeable plastic bag. In the case of the plastic bag that is boiled and heated with boiling water, the material of the bag is impermeable to water and water vapor. Can be supplied only by conduction heat transfer through the plastic film, and the amount of heat transferred is proportional to the temperature difference between the inside and outside of the bag, and the efficiency decreases as it gradually decreases. there were. On the other hand, according to the present invention, since the water vapor directly penetrates into the bag, heat can be directly supplied to the object to be heated inside the bag, and the amount of heat transferred is a large amount of latent heat of condensation of water vapor, so that a large amount of heat can be transmitted. Not only does it have to do with the temperature difference between the inside and outside of the bag,
Efficient. In addition, there is no need to improve the heating efficiency as in the case of plastic bags or to prevent the bags from breaking, that is, deaeration adhesion and liquid encapsulation are unnecessary, and solid materials that easily collapse and water soluble It is particularly convenient for things that easily fall apart. It is particularly advantageous when used for solid frozen foods, refrigerated foods, or foods distributed at room temperature.

Even when compared with the conventional steamer, if the juice of the food is intended to be distributed by thawing or heating, such as in the case of frozen food, if the food is placed naked on the steamer of the steamer. In contrast, in the present invention, the juice spills and dissipates, whereas in the present invention the juice is kept in the container, which is particularly convenient for foods where the umami of the juice is important. In addition, even if the container is placed on the bowl of the steamer and steamed and heated, the heating efficiency is lowered, but steaming is possible.

[0045]

EXAMPLES Next, Table 1 summarizes Examples and Comparative Examples expressing their effects. In addition, in each example, the object to be heated is 100 g in weight, which is not seen to be wet and dry with the same property.
r Chinese steamed bun, the heat source for heating and boiling water is a gas stove with a heat amount of 1800 kcal / h, and the water amount immediately before heating the object to be heated is commonly 500 cc. And, to describe the specifications of the pot or steamer containing the water, the pot has 3 cm radius at the four corners
It was made of rectangular stainless steel and had a height of 8 cm and a height of 8 cm, and a lid was used. The steamer is made by stacking a stainless steel cage with a round hole at the bottom and a height of 8 cm on the top of the pot. The distance between the bottom and the water surface is 4
cm and a lid was used. The heat power was adjusted while checking the length of the flame, but it was divided into two types: strong and weak. The relationship between the length of the flame and the pan at that time is shown in Fig. 1 and Fig. 2
Illustrates weakness. The container is immersed in water after boiling the water, and the heating time is the time from immersion in water to removal. The specifications of the container are shown in Figures 2 and 3.

In Comparative Example 1, the size of the portion of the container in contact with water was 18 seconds, but when the heating power was low,
Wetting of the heated object was observed. Also, in Comparative Example 2, the sizing degree of the portion of the container in contact with water is 18 seconds as in Comparative Example 1, but when the heating power was high, no wetness of the heated object was observed and the finish was good. It was On the other hand, in Example 1, the sizing degree of the portion of the container in contact with water was 20 seconds, but even if the heating power was weakened, the object to be heated was not wet with water and the finish was good. Further, in Example 5, when the heating was carried out with high heat, there was no water wetting or drying, and the finish was good. Therefore, it can be said that the sizing degree of the portion of the container in contact with water is preferably 20 seconds or more so that the finish is good even if the heating power is weak. And not only the first embodiment but also the second, third, fourth, sixth, seventh, eighth, ninth and tenth embodiments.
I can say that even in the case of water, no matter how strong or weak the firepower is, wetting is not seen.

On the other hand, an example in which the air permeability is confirmed will be described. The air permeability of Examples 1, 2, 5, 6, 7, 8, 9 and 10 is 800 seconds or less, but Examples 1, 2, 6, 7,
In Nos. 8, 9 and 10, the air permeability was 200 seconds or less and the heating power was weak, and heating for 10 minutes was sufficient to give a warm finish, whereas in Example 3, the air permeability was 800 seconds. However, when heated for 10 minutes on high heat,
There was no problem, but the warmth was insufficient. Therefore, in the fourth embodiment, the heating power is increased to 20
After heating for a minute, sufficient warmth and finish were obtained. On the other hand, Comparative Examples 3 and 4 were carried out with an air permeability of 820 seconds, but Comparative Example 3 was carried out with high heat power. I got it. Further, in Comparative Example 4, when the heating power was weakened, the bag was not broken, but it was not warm and the finish was unsatisfactory because the surface felt a hardness. Therefore, it can be said that the air permeability of at least a part of the portion of the container that comes into contact with water is preferably 800 seconds or less.

Next, a part of an example in which what happens depending on the form of the container is confirmed will be described. Examples 1 to 5 were bags, Example 6 was a box, Examples 7 and 10 were plates, Example 8 was a boat boat type, and Example 9 was a sheet wrapped. The finishes of Examples 6, 7, 8 and 9 were good, and the warmth was sufficiently high, and the finish was similar to that of Examples 1, 2, 4 and 5. On the other hand, in Example 10, the outer periphery of the container touched the inner wall of the pot and was melted. Explaining the difference between Example 10 and Example 7, Example 10 has plastics on the outer periphery, whereas Example 7 is entirely made of paper,
In Example 7, the outer peripheral portion of the container touched the inner wall of the pan, but no melting was observed. It is considered that Example 7 did not melt due to the heat resistance of the paper and the cooling effect of water absorption.
From the above, whether the container is box-shaped, bag-shaped, dish-shaped, or house-shaped,
It can be said that the present invention has some effects.

Next, reference will be made to Comparative Examples 6 and 7 for comparison with the method of the present invention. Examples 3, 4, 5 and Comparative Example 6
Both of them have strong thermal power, but in Comparative Example 6, the object to be heated was dried, whereas in Examples 3, 4, and 5, neither drying nor wetting was observed, and the finish was appropriate. This is because in each of the examples, the thermal power is strong and the atmosphere above the water surface is higher than the boiling point of water, so in Comparative Example 6, the water vapor generated from the water surface is overheated in the process toward the heating target on the cage. Since it is in a dry state, when it reaches the object to be heated, water is taken away from the object to be heated, while in Examples 3 and 4,
In FIG. 5, the water surface and the lower surface of the object to be heated are not in contact with each other but are close to each other, and the generated steam reaches the object to be heated with almost no influence of the surrounding superheated dry state atmosphere. It is considered that it could be heated without heating.

As compared with Comparative Example 7, Examples 1, 2, 6, 7,
Compare 8, 9, and 10. Although the heating power was weakened in both cases, in Comparative Example 7, the object to be heated was seen to be wet with water, whereas in Examples 1, 2, 6, 7, 8, 9 and 10, neither drying nor wetting was performed. It is a moderate finish without being seen. This is because the heat power is weak in each example and the atmosphere above the water surface is lower than the boiling point of water. Therefore, in Comparative Example 7, water vapor generated from the water surface is cooled and drops into droplets in the process toward the heating target on the cage. It becomes steam with a lot of dampness, and the object to be heated gets wet, or the water vapor that jumps out from the liquid field to the air field when boiling boils and wets the object to be heated through the hole in the dango. In contrast, Examples 1, 2, 6, 7, 8, 9, 10
However, since the water surface and the bottom surface of the heating target are not in contact with each other but are close to each other, the generated steam reaches the heating target almost without being affected by the surrounding moist atmosphere, and the heating target does not get wet. It is considered that the object to be heated did not get wet because the object to be heated was separated from the liquid water in the container and the water droplets accompanied by the steam during boiling were blocked by the container.

[0051]

EFFECTS OF THE INVENTION By the steam heating method and the food container of the present invention, the object to be heated is easily heated and has an appropriate amount of moisture, resulting in good efficiency and finish. In addition, even if you do not use equipment such as a basket or steamer that has a child's cage or special equipment such as a steam generator, you can steam it with anyone's pot and heating equipment, so anyone anywhere can use it for home use. However, even for commercial use, regardless of the size of the scale and the degree of equipment, steam cooking can be done easily, and the effect is great. In addition, when it is made into a sheet, plate-shaped body or bag, it does not take up much space for storage and storage, even if it is a box-shaped container such as paper, it does not take up much space for storage and storage, and it is lightweight and resource-saving. Yes, it is more convenient to dispose of if paper is used.

[Brief description of drawings]

FIG. 1 shows a state of a flame in which a pot has a strong heating power.

FIG. 2 shows a state of a flame in which the pot has a weak heating power.

FIG. 3 shows an arrangement state of a container and paper.

FIG. 4 is a diagram 1 showing an example and a comparative example expressing the effect thereof.

FIG. 5 is a diagram 2 showing specifications of containers used in Examples and Comparative Examples of the present invention.

[Explanation of symbols]

 1 pot 2 water 3 stove 4 flame 5 bag 6 plastics 7 paper

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] November 24, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Delete

Claims (14)

[Claims] 1. A value measured by the method specified in Japanese Industrial Standard P8122-1976, Steckigt / Sizing test method for paper is 20 seconds or more for all parts in contact with water,
At least a part of the part in contact with water is Japanese Industrial Standard P81
17-1980, wrap the object to be heated in a container made of a material whose value measured by the method specified in the air permeability test method for paper and paperboard is 800 seconds or less, and immerse the lower outer part of the container in water. A method of steaming and heating an object to be heated by heating. 2. The steaming method according to claim 1, wherein the container is a sheet. 3. The steaming method according to claim 1, wherein the container is a bag. 4. The steaming method according to claim 1, wherein the container is a box. 5. The method for steaming and heating according to claim 1, wherein the container is a dish. 6. The steaming and heating method according to claim 1, wherein the container is paper. 7. The steaming method according to claim 1, wherein the container is a paper bag. 8. The steaming method according to claim 1, wherein the container is a container whose side end portion is made of paper. 9. The steaming method according to claim 1, wherein the container is a composite material container. 10. The steaming and heating method according to claim 1, wherein the container is a container made of a composite material of paper and plastics. 11. The steam heating method according to claim 1, wherein the container is a container made of a composite material of paper and plastics, in which a thermoplastic resin is placed inside the container. 12. The steam heating method according to claim 1, wherein the container is a container made of a composite material of paper and plastics, which is made by disposing a hydrophilic thermoplastic resin inside the container. 13. The steaming and heating method according to claim 1, wherein the container is a container made of a composite material of paper and plastics in which an ionomer resin is placed inside the container. 14. A food container used in the steam heating method according to claim 1.