JP3604109B2 - Manufacturing method of sterilized solid food ingredients - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to a method for producing a sterilized solid food material that can be stored for a long period of time by heat sterilization and in which only solid substances are packaged.
[0002]
[Prior art]
In recent years, various food materials used for foods are widely collected from all over the world, and are provided as final processed foods after several stages of processing steps. Under these circumstances, raw foodstuffs have poor preservability, and it is desirable that the primary processing be carried out as early as possible to improve the preservability, and then be transferred to the next processing stage. Needless to say, a processing method that can maintain the flavor, color tone, and texture of the product as much as possible is optimal.
[0003]
The primary treatment for improving the preservability in this manner includes low-temperature treatment such as refrigeration and freezing, and sterilization treatment by various methods. Examples of the sterilization treatment include a method of performing continuous sterilization in a closed in-line and a method of sterilizing boiled or retorted foodstuffs tightly packed.
[0004]
Low-temperature storage such as freezing and refrigeration requires energy and equipment to maintain low temperatures, which increases not only the economic burden but also the environmental burden. In addition, the storage period of refrigeration is limited, and long-term storage in the true sense is difficult. In the case of freezing, it can be stored for a long period of several months to one year, but it has the disadvantage that the tissue is destroyed due to the expansion of water during freezing and the umami component drops out due to dripping when thawing. .
[0005]
On the other hand, the above-mentioned boiling or retort sterilization allows storage at room temperature. If storage at room temperature is possible, these energies become unnecessary and simple transportation and storage are possible.
[0006]
In addition, the sterilization apparatus in the above-mentioned in-line system can sterilize only solids having a size equal to or smaller than a certain size (maximum 30 mm square) due to the characteristics of the apparatus. In addition, since continuous sterilization is performed in a closed inline as described above, a continuous phase that is a fluid such as a liquid for flowing a solid food is indispensable. When such a continuous phase is present, the umami components and colors of the ingredients shift to the continuous phase during heat sterilization, and the components in the continuous phase are transferred to the ingredients, resulting in the flavor and color tone originally possessed by the ingredients. Will change. In addition, when the texture of the food material is soft or brittle, the food material may be crushed, chipped, or split while flowing in the continuous phase, resulting in a shape different from the original shape.
[0007]
In the above-mentioned boil or retort sterilization, since the continuous phase is eliminated by tightly packing beforehand and heating is performed in a stationary state, there is no such problem.
[0008]
[Problems to be solved by the invention]
However, in the above-mentioned boil or retort sterilization, heating is performed by heat conduction from the outside, so long heating is required to completely sterilize the center of the food, and sterilization can be performed at a high temperature in as short a time as possible. Can not. As a result, there is no choice but to overheat as a whole. Therefore, there are always problems such as heating odor and fading. In addition, in the case of a food material having a soft texture, the food collapsed due to overheating, and an excellent food texture could not be obtained. Therefore, these solid foods are only seasoned foods with a high degree of cooking and are strongly colored, and the above-mentioned method is suitable for long-term storage of re-cookable ingredients that retain the flavor of the ingredients themselves. Was not the way.
[0009]
In addition, in the case of simultaneously heating solid foods of different sizes, or heating of partially different thicknesses of solid foods, in order to heat the largest size or the thickest portion so that they can be sufficiently sterilized. In addition, small solid foods and thin portions in the solid foods are further overheated.
[0010]
As described above, with the conventional sterilization method, it is impossible to produce aseptic solid foodstuffs of good quality, which maintain the flavor, color, and texture of the original foodstuffs, especially the original foodstuffs, and have various sizes and shapes. There is a problem.
[0011]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for producing a sterilized solid food that can be stored at room temperature for a long period of time and that retains the flavor of the material.
[0012]
[Means for Solving the Problems]
In order to solve the above problems, a method for producing a sterilized solid food material of the present invention is a package in which the solid food material and the packaging material are closely adhered to each other by tightly packaging the solid food material with a packaging material in a non-sterile state. , And the package is sterilized by dielectric heating.
[0013]
According to the method described above, the periphery of the solid food material is tightly packed with a packaging material in a non-sterile state, and sterilized by dielectric heating.
[0014]
Therefore, by previously packing the solid foodstuff in close contact, the continuous phase for flowing the solid foodstuff, which has been conventionally required, can be eliminated from the inside of the package. Moreover, since sterilization is performed using internal heat generated by dielectric heating, rapid and uniform heat sterilization can be performed.
[0015]
Therefore, it is possible to obtain a high-quality sterilized solid food material that can be stored at room temperature for a long period of time and retains the original flavor, color tone, and texture of the material.
[0016]
Method for producing a sterilized solid food of the present invention, in addition to the above configuration, the frequency of the field used for the dielectric heating can be configured to be 1MHz to several GHz.
[0017]
Method for producing a sterilized solid food of the present invention, in addition to the above structure is characterized in that the frequency of the electric field used for the dielectric heating is to not 1 MHz 100 MHz.
[0018]
According to the above method, the package is sterilized by dielectric heating using an electric field having a frequency of 1 MHz to 100 MHz. Therefore, the high-frequency electric field is more uniformly applied to each part of the package. Therefore, the influence of the size and shape of the solid food on uniform heating can be further reduced. Therefore, in addition to the effect of the above configuration, it is possible to more uniformly heat and sterilize.
[0019]
Method for producing a sterilized solid food of the present invention, in addition to the above, as well as arranging the package in a container, sealed fluid to the vessel, placing the vessel between the electrodes, the The dielectric heating is performed by applying a high-frequency electric field between the electrodes.
[0020]
According to the above method, the solid foodstuff, which is tightly packaged with the packaging material in a non-sterile state, is sealed in the container. Also, the fluid is sealed in the container, and the container comes into uniform contact with the entire package. By performing dielectric heating through this fluid, uniform application of a high-frequency electric field can be performed even more effectively to every corner of the package. Therefore, the influence of the size and shape of the solid food on uniform heating can be further reduced. Therefore, in addition to the effects of the above-described configuration, it is possible to more uniformly heat and sterilize. The fluid is, for example, water, an aqueous solution, a fat, or a gel.
[0021]
The method for producing a sterilized solid food material of the present invention is characterized in that, in addition to the above-described configuration, the fluid is selected from an aqueous solution, an oil, and a gel.
[0022]
The method for producing a sterilized solid food material of the present invention is characterized in that the fluid is water in addition to the above configuration.
[0023]
The method for producing a sterilized solid food material according to the present invention is characterized in that, in addition to the above-described configuration, the container has an aluminum plate that comes into contact with each of the electrodes, and has a cylindrical shape whose side surface is surrounded by a polyimide resin. I have.
[0024]
Method for producing a sterilized solid food of the present invention, in addition to the above structure, it is characterized in that the solid foodstuff is a raw food material. The raw ingredients are, for example, meat, fruit, fish meat, vegetables, eggs and the like.
[0025]
Method for producing a sterilized solid food of the present invention, in addition to the above structure, it is characterized in that the solid foodstuff is a confectionery. The raw confectionery is, for example, pudding, jelly, mousse, mizuyokan, chimaki, bun, Daifuku and the like.
[0026]
The sterilized solid food material of the present invention can be configured to be tightly packed with a packaging material and sterilized by dielectric heating. Moreover, the sterilized solid foodstuff of the present invention may have a structure in which the solid foodstuff tightly packaged with a packaging material is a fruit in addition to the above-described structure.
[0027]
The method for producing a sterilized solid food material of the present invention is characterized in that, in addition to the above configuration, the solid food material is maintained at a sterilization temperature in a range of 120 ° C to 180 ° C for 0 to 180 seconds to perform the dielectric heating. And
[0028]
In the method for producing a sterilized solid food material of the present invention, in addition to the above-described configuration, the container is provided with an inlet / outlet and an opening / closing valve for air or water for increasing the internal pressure of the container. Features.
[0029]
BEST MODE FOR CARRYING OUT THE INVENTION
The following will describe one embodiment of the present invention.
[0030]
The food material in the present invention is not particularly limited, but the effect is greater as solid materials that are close to raw, such as meat, fish, vegetables, fruits, and the like, and those that have physical properties that are easily broken such as mousse and jelly. .
[0031]
In the present invention, the target food material is first tightly packed with a packaging material such as a packaging film, but the packaging method at that time is not particularly limited, and the packaging is performed on the food material after packaging, such as vacuum packaging or carbon dioxide absorption packaging. The materials need only be in close contact. The packaging film only needs to have flexibility and heat resistance and also have electromagnetic wave permeability, and the material is not particularly limited. For example, CP (cellulose propionate), PP (polypropylene), nylon, PET (polyethylene terephthalate), a laminated film thereof and the like can be mentioned.
[0032]
The foodstuff tightly packed can be subjected to microwave irradiation in a microwave oven as it is, or placed between electrodes to which a high-frequency voltage is applied, so that heat sterilization can be performed by dielectric heating. The microwave here refers to 2450 MHz and its peripheral frequencies, and the high frequency refers to 1 MHz to several hundred MHz. That is, it means that dielectric heating using a frequency of 1 MHz to several GHz is used as a whole. However, among them, the dielectric heating at a frequency of 1 MHz to 100 MHz used in the present invention is hardly affected by the size and shape of the solid foodstuff, and in that respect, it has also been found that it is preferable to the case where a higher frequency is used. did.
[0033]
In addition, when performing dielectric heating at a frequency of 1 MHz to 100 MHz, a solid food material that is to be heated and tightly packed is sealed between two electrodes, and is a fluid such as water, an aqueous solution, an oil or fat, or various gels. It is also possible to sterilize by heating by placing it inside and applying a high-frequency electric field between the electrodes. In this case, more uniform heat sterilization is possible. The fluid used at this time may have a dielectric heating efficiency similar to that of the solid food to be heated, and it is usually desirable to use water or an aqueous solution to which various sugars and salts are added.
[0034]
As the sterilization conditions, it is desirable to set the sterilization temperature to 120 ° C. to 180 ° C. and to perform short-time sterilization for 0 to 180 seconds.
[0035]
Generally, the sterilization time M at an arbitrary temperature T _i is calculated by the following equation.
M = F × 10 ^{(Tr-Ti) / z}
In this equation, F is a required F value, _Tr is a reference temperature, _Ti is an arbitrary temperature, and z is a parameter indicating heat resistance of the microorganism. The reference temperature _Tr , the value of z, and the F value are set according to the properties of individual foods. Is usually at least 4 minutes. The sterilization temperature is maintained only during the sterilization time M.
[0036]
The solid food thus sterilized has no continuous phase, is solid only, and is sterilized for a short time, so it retains the original flavor and texture well, and loses its shape because it is heated in a stationary state. There is no good solid material.
[0037]
【Example】
Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.
[0038]
〔apparatus〕
The apparatus used in this example is as follows.
[0039]
A microwave oven having a power of 1.5 kW (referred to as an apparatus A) was used for a microwave region test as a reference example . In order to perform heating in a pressurized state, PEEK (polyether ether ketone) is provided with an air inlet / outlet and respective opening / closing valves so that a sample can be charged into the inside and the air pressure in the container can be increased. ) Was prepared (referred to as container A).
[0040]
On the other hand, as shown in FIG. 1, in a test in a high frequency region, a vacuum tube type high frequency oscillator 2 which oscillates a frequency of 13.56 MHz at a maximum output of 7 kW, and a tuning for maintaining high frequency tuning in accordance with an object to be heated. A sterilizing apparatus 1 comprising an upper electrode plate 5a connected to the high-frequency oscillator 2 via a circuit 3, and a heating unit 4 having another grounded lower electrode plate 5b facing in parallel with the upper electrode plate 5a. (Referred to as apparatus B). A press cylinder 7 is connected to the upper electrode plate 5a, and can be pressed toward the lower electrode plate 5b.
[0041]
Further, in order to perform heating in a pressurized state, a cylindrical hermetic container 6 (container) having upper and lower aluminum plates respectively in contact with the upper electrode plate 5a and the lower electrode plate 5b and having side surfaces surrounded by a polyimide resin. B) was prepared. The container B is provided with an air inlet / outlet and respective opening / closing valves so that the air pressure in the container can be increased.
[0042]
[Packaging]
In this example, a film in which CP was laminated on the inner surface and nylon was laminated on the outer surface was used as a packaging material, and the film was closely packaged by a vacuum packaging machine.
[0043]
〔sample〕
In this embodiment, as solid ingredients, beef fillet (square cut with a side length of about 40 to 60 mm), raw cod and raw red trout (half cut of a length of about 40 to 60 mm), strawberry fruit, banana Using a fruit (40 mm thick slices) and fresh broccoli (subdivided into about 1 bunch), the above-mentioned vacuum packaging was performed so that each pack weighed about 200 g to obtain a sample.
[0044]
( Reference example )
After the sample is put into the container A and sealed, air is injected from the air inlet to make the pressure inside the container 4 kg / cm ² , and then the inside of the device A becomes 120 ° C., 140 ° C. and 180 ° C. Heating was performed. Thereafter, the temperature is maintained at 180 ° C. for 180 seconds, at 140 ° C. for 5 seconds, and at 180 ° C. for 0 seconds, and then taken out of the apparatus A, and the sample is removed by replacing the air in the container with water. After cooling to about 80 ° C., the container was opened, the sample was taken out, and the sample was further cooled to 15 ° C. in cold water.
[0045]
This operation was performed for each sample to obtain a sample of each sterilized food. Using this sample, cooking such as boiling, baking, and steaming resulted in a food product having a flavor and color comparable to that of using raw ingredients. In addition, in the case of strawberries and bananas, the shape remained very well without collapse, and the appearance was beautiful.
[0046]
[Example 1 ]
After the sample was put into the container B and sealed, air was injected from the air inlet, the pressure inside the container was set to 4 kg / cm ² , then sandwiched between the upper electrode plates of the device B, and a high-frequency electric field was applied. Heating was performed until the sample reached 120 ° C, 140 ° C, and 180 ° C. Thereafter, the temperature is maintained for 180 seconds at 120 ° C., 5 seconds at 140 ° C., and 0 seconds at 180 ° C., and then taken out of the apparatus B, and the sample is removed by replacing the air in the container with water. After cooling to about 80 ° C., the container was opened, the sample was taken out, and the sample was further cooled to 15 ° C. in cold water.
[0047]
This operation was performed for each sample to obtain a sample of each sterilized food. Using this sample, cooking such as boiling, baking, and steaming resulted in a food product having a flavor and color comparable to that of using raw ingredients. In addition, in the case of strawberries and bananas, the shape remained very well without collapse, and the appearance was beautiful.
[0048]
[Example 2 ]
After the sample was put into the container B and sealed, water was injected from the air inlet to make the pressure inside the container 4 kg / cm ² , and then sandwiched between the upper and lower electrode plates of the device B, and a high-frequency electric field was applied. Heating was performed until the sample reached 120 ° C, 140 ° C, and 180 ° C. Thereafter, the temperature is maintained at 180 ° C. for 180 seconds, at 140 ° C. for 5 seconds, and at 180 ° C. for 0 seconds. After cooling to about 80 ° C., the container was opened, the sample was taken out, and the sample was further cooled to 15 ° C. in cold water.
[0049]
This operation was performed for each sample to obtain a sample of each sterilized food. Using this sample, cooking such as boiling, baking, and steaming resulted in a food having a flavor and color comparable to that of using raw ingredients. In addition, in the case of strawberries and bananas, the shape remained very well without collapse, and the appearance was beautiful.
[0050]
【The invention's effect】
As described above, the method for producing a sterilized solid food material of the present invention forms a package in which the solid food material and the packaging material are closely adhered to each other by tightly packaging the solid food material in a non-sterile state with a packaging material. And a method of sterilizing the package by dielectric heating. A method of manufacturing a sterilized solid food of the present invention, in addition to the above structure is a method the solid ingredients are raw ingredients. Further, the method of producing sterilized solid food of the present invention, in addition to the above structure is a method the solid ingredients are confectionery.
[0051]
The method for producing a sterilized solid food material of the present invention has a configuration in which the fluid is selected from an aqueous solution, an oil, and a gel in addition to the above configuration.
[0052]
The method for producing a sterilized solid food material of the present invention has a configuration in which the fluid is water in addition to the above configuration.
[0053]
In the method for producing a sterilized solid food material of the present invention, in addition to the above-described structure, the container has a cylindrical shape having an aluminum plate in contact with each of the electrodes, and a side surface surrounded by a polyimide resin.
[0054]
The method for producing a sterilized solid food material of the present invention is such that, in addition to the above-described configuration, the above-mentioned solid food material is maintained at a sterilization temperature in a range of 120 ° C to 180 ° C for 0 to 180 seconds to perform the dielectric heating. .
[0055]
The method for producing a sterilized solid food material of the present invention has a configuration in which, in addition to the above configuration, the container is provided with an inlet / outlet and an opening / closing valve for air or water for increasing the internal pressure of the container. is there.
[0056]
Therefore, it is possible to obtain a high-quality sterilized solid food material that can be stored at room temperature for a long period of time and that retains the original flavor, color tone, and texture of the material.
[0057]
Method for producing a sterilized solid food of the present invention, in addition to the above structure is a method frequency of the electric field used for the dielectric heating is to not 1 MHz 100 MHz.
[0058]
Therefore, in addition to the effect of the above-described method, an effect is obtained that heating and sterilization can be performed more uniformly.
[0059]
Method for producing a sterilized solid food of the present invention, in addition to the above, as well as arranging the package in a container, sealed fluid to the vessel, placing the vessel between the electrodes, the This is a method in which a high-frequency electric field is applied between the electrodes to perform the dielectric heating.
[0060]
Therefore, in addition to the effect of the above-described method, there is an effect that heating and sterilization can be performed more uniformly.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing one configuration example of a sterilization apparatus according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Sterilizer 2 High frequency oscillator 3 Tuning circuit 4 Heating part 5a Upper electrode plate 5b Lower electrode plate 6 Sealed container 7 Press cylinder

Claims (8)

Forming a package in which the solid food and the packaging material are in close contact with each other by tightly packaging the solid food with a packaging material in a non-sterile state,
While placing the package in a container, enclosing the fluid in the container,
Place the container between the electrodes,
A method for producing a sterilized solid food material, wherein the package is sterilized by dielectric heating by applying a high-frequency electric field having a frequency of 1 MHz to 100 MHz between the electrodes . The method for producing a sterilized solid food material according to claim 1, wherein the fluid is selected from an aqueous solution, a fat, and a gel. The method for producing a sterilized solid food material according to claim 1, wherein the fluid is water. The method for producing a sterilized solid food material according to any one of claims 1 to 3, wherein the container has an aluminum plate in contact with each of the electrodes, and has a cylindrical shape with a side surface surrounded by a polyimide resin. . The method for producing a sterilized solid food material according to any one of claims 1 to 4, wherein the solid food material is a raw food material. The method for producing a sterilized solid food material according to any one of claims 1 to 4, wherein the solid food material is a raw confectionery. The manufacturing of the sterilized solid food material according to any one of claims 1 to 6, wherein the dielectric heating is performed while maintaining the solid food material at a sterilization temperature in a range of 120C to 180C for 0 to 180 seconds. Method. The sterilized solid food material according to any one of claims 1 to 7, wherein the container is provided with an air or water inlet / outlet and a respective open / close valve for increasing the pressure in the container. Production method.

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