JP2931840B2 - Food heating device and heating method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a food heating device and a heating method for heating a food having conductivity by supplying an electric current to the food with Joule heat. .

[Conventional technology]

Conventionally, a surimi heating device is disclosed in Japanese Patent Application Laid-Open No. 2-49564, and its structure is such that, as shown in FIG. A pair of electrodes 103, 1 fixed to the tip of the piston rod 102
03 is pressed down, and the piston rod 1
An alternating current is supplied to the surimi 101 through the electrode 02 and the electrode 103 or directly only through the electrode 103, and the surimi 101 is heated by generating Joule heat. Before this heating device was invented, surimi was steamed in steam at 85 to 100 ° C. for about one hour to produce a product, but according to a heating device using Joule heat, it was about 3 hours. This is a breakthrough in the sense that similar products can be manufactured in minutes and the manufacturing cost can be significantly reduced.

In general, stainless steel is often used for food processing machines, but stainless steel is used as the electrode of the heating device because chromium and nickel mixed with stainless steel are eluted into the surimi by local electrolysis (electrolytic corrosion). Therefore, an electrode made of aluminum is used. However, when an aluminum electrode is used, the electrode must be frequently inspected or replaced, and the production line must be stopped each time, which hinders a reduction in food production costs.

Therefore, in order to spread this revolutionary heating device using Joule heat, the development of the above-mentioned electrode was indispensable.

[Problems to be solved by the invention]

In view of the above situation, the present invention seeks to solve the problem by using a non-ionized substance as a heating electrode, that is, a conductive material made of a stable substance that is not electrochemically oxidized or reduced, and thus has no adverse effect on food. Another object of the present invention is to provide a heating device and a heating method for a food product which do not cause electric corrosion, do not cause electrolytic corrosion even when an electric current is applied, and have high durability.

[Means for solving the problem]

In order to solve the above-mentioned problems, the first invention uses a conductive material in which carbon or graphite powder or short fibers are supported by a resin binder on the surface of an electrode substrate at least in a portion in contact with a conductive food. An electrode formed with a layer is arranged in contact with the food, and the food is heated by Joule heat generated by supplying an electric current from the electrode into the food.

Here, by using an electrode in which the resistance value of the conductive layer on the surface in contact with food is appropriately changed according to the position of the contact surface, uniform heating or partial priority heating can be performed.

In addition, the second invention provides a food product using an electrode in which a plurality of small electrodes in which a conductive layer is formed using a conductive material made of a non-ionizable substance at least in a portion in contact with a conductive food product are assembled via an insulator. Is constituted.

Further, an electrode or a small electrode in which the conductive layer is formed on the surface of an electrode substrate or formed using only the conductive material is used.

Further, an electrochemically stable conductive layer was formed using a conductive material having a carbon component.

Then, a third invention which is a method of heating food is a food having conductivity, formed by using a conductive material in which carbon or graphite powder or short fiber is supported on a surface of an electrode substrate by a resin binder. The food is heated by contacting the conductive layer and supplying an electric current into the food through the conductive layer to generate Joule heat.

[Action]

The food heating device and the heating method of the present invention having the above-mentioned contents use a conductive material in which carbon or graphite powder or short fiber is supported by a resin binder at least in an electrode portion in contact with a food having conductivity. The formation of the conductive layer prevents ionizing metals such as conventional electrode materials from coming into contact with food, eliminating the adverse effects of electrolytic corrosion, and providing sufficient current to generate Joule heat in food. Supply.

In addition, by forming a conductive layer on the surface of the electrode substrate, a metal, synthetic resin, or inorganic electrode substrate can be used, and a shape-stable electrode or a flexible electrode can be selected according to various forms of food. It is.

Furthermore, when the resistance value of the conductive layer on the surface in contact with the food is appropriately changed according to the position of the contact surface, the amount of current supplied to the food from the conductive layer can be adjusted in each part of the food, Thereby, uniform heating or partial preferential heating can be performed.

When a conductive material having a carbon component is used as the conductive material, the conductive material is stable without electrochemical oxidation and reduction.

In addition, a plurality of small electrodes in which a conductive layer is formed using a conductive material in which carbon or graphite powder or short fibers are supported by a resin binder at least in contact with a food having conductivity are assembled via an insulator. By using electrodes, the amount of current supplied to the food from each small electrode can be adjusted in each part of the food,
An electric current can also flow between the small electrodes constituting one electrode.

〔Example〕

Next, the present invention will be described in further detail with reference to embodiments shown in the accompanying drawings.

The present invention relates to an apparatus and a method for heating a food by supplying Joule heat by supplying an electric current into the food from an electrode arranged in contact with the conductive food, and heating the food. The present invention is characterized in that a conductive layer provided on at least an electrode portion in contact with food is formed of a conductive material made of a non-ionizable substance.

It is more preferable to use a conductive material having a carbon component, particularly a conductive material made of powdery or fibrous (including short fibers) carbon or graphite, as the conductive material. Then, a conductive layer using a conductive material made of carbon or graphite, first, a paste-like conductive material in which a powder of carbon or graphite or short fibers are combined with a binder and a solvent is applied to the surface of the electrode substrate, and heated. Those formed by solidification are exemplified. Here, as the binder, organic substances such as epoxy, polyester, silicon, fluorine-based resin or rubber, and inorganic substances such as glass frit are preferable. In addition, carbon or graphite powder or short fibers are sintered or cold-pressed directly on the electrode substrate surface and directly consolidated, or woven or non-woven fabrics are formed from carbon or graphite long fibers. It is contemplated to form a layer. Further, a plate-like material of carbon or graphite may be laminated on the surface of the electrode substrate.

The food to be heated according to the present invention is not limited to a paste, a solid or a liquid, as well as a product or a semi-finished product, as long as it contains water and an electrolyte such as salt and has a predetermined or higher conductivity. Wide variety. For example, as a pasty food, a mixture of auxiliary ingredients such as seasonings and starch (such as kamaboko, bamboo rings, hampan, datemaki, etc.), pork, beef, etc. Similarly minced meat of raw meat (sausage, etc.)
Is mentioned. Examples of solid foods include seafood (octopus, squid, boiled shellfish, etc.), livestock meat (ham, baked pork, etc.), grain powder (pasta, noodles, Chinese noodles, etc.), and dairy products (cheese, etc.). No. Further, liquid foods include liquids (soups, sauces, thick-fried eggs, etc.) and liquids containing solids (curries, stews, jams, etc.). In addition, vegetables, potatoes,
It is also applicable when boiling or blanching beans and grains. Furthermore, the present invention can be applied to thawing frozen foods (such as tuna).

 Examples will be described in more detail below.

1 and 2 show a first embodiment of a food heating apparatus according to the present invention, which is an apparatus for heating a food 2 using an electrode 1 having a special structure. The heating device has at least a pair of electrodes 1,
Other structures and mechanisms are not particularly limited as long as the food 2 is held between the two, the electrode 1 and the food 2 are always in contact, and an electric current can be supplied to the food 2 via the electrode 1. The feature of the present invention lies in the structure of the electrode 1 used for heating, and the following embodiment describes the structure of the electrode 1 itself and the arrangement of the electrode 1 and the food 2.

In the present embodiment, a case is described in which surimi such as fish meat is heated as the food 2 when manufacturing a paste-like food such as kamaboko.

The electrode 1 of the first embodiment is adjusted to have a desired conductivity by using the conductive material made of a non-ionizable substance on the surface of an electrode substrate 3 made of aluminum or the like, particularly on one side in contact with the food 2. Thus, the conductive layer 4 is formed.
Specifically, a conductive material in which carbon or graphite powder or short fibers are supported by a resin binder is applied to the surface of the electrode substrate 3 or laminated by screen printing or the like to form a conductive layer 4. Layer 4 is electrode substrate 3
Is formed on the entire surface or at least a portion in contact with the food 2.

The conductivity of the conductive layer 4 varies depending on the density ratio of the synthetic resin and the carbon or graphite powder or short fiber and the particle size of the powder. When the conductivity is extremely low, the conductive layer becomes a heating element, and when the conductivity is extremely high, the conductivity increases. Since the ratio of the synthetic resin is reduced and the carbon or graphite powder or short fiber cannot be completely supported and peels off from the conductive layer 4, it is necessary to set an appropriate conductivity according to the supplied current density. To change the resistance value of the conductive layer 4 on the surface in contact with the food 2 according to the position of the contact surface,
A method of changing the density of carbon or graphite powder or short fibers while keeping the thickness of the conductive layer 4 constant;
There are a method of forming the conductive layer 4 by changing the thickness of the conductive layer 4 using a conductive material having a constant conductivity, and a method of forming the conductive layer 4 by changing both at the same time.

In order to actually heat the food 2, the plate-shaped electrodes 1, 1 were inserted between the open ends of both sides of the insulating cylinder 5 with the food 2 interposed therebetween, and connected to the back surface. The piston rods 6 press the rods in a direction of approaching each other, and at the same time, supply an electric current from the power source 7 through the piston rods 6 and the like to generate Joule heat by the electric current flowing in the food 2.

The power supply 7 may supply a commercial voltage and a current of a frequency. In the experiment, a current of 100 V, 50 Hz, and 5 A is applied to a cross-sectional area of about 5 V.
20 cm ² (current density about 0.25 A / cm ² ) about 3 for cylindrical food 2
For a minute, a taste similar to that of a conventional steamed kamaboko, and a product with a chewy texture were obtained. In the present invention, the current supplied to the food 2 is preferably an alternating current, and as a modification thereof, a square wave current or a pulse current is used. It does.

Although a preferable example of the electrode substrate 3 is made of aluminum, the electrode substrate 3 is made of metal such as iron, titanium, stainless steel, platinum and their alloys, or as shown in FIG. What laminated | stacked the metal thin film layer 9 on the surface of the synthetic resin base material 8 is also possible. Here, as the material of the synthetic resin base material 8, since the food 2 contains moisture and it is difficult to raise the temperature to 100 ° C. or more even when heated, polyester, polypropylene, polyimide, epoxy resin,
Although all synthetic resins that can be used as food containers, such as silicone resin, can be used, those having high heat resistance are more preferable. Further, as the metal thin film layer 9, a metal foil, particularly an aluminum foil, is suitable for food hygiene, and the method of laminating the metal thin film layer 9 on the synthetic resin base material 8 is performed by laminating using an adhesive 10, particularly in sheet form. The electrode 1 is formed by lamination by an extrusion method or a lamination technique. As another example, the metal thin film layer 9 can be formed by directly depositing a metal material on the synthetic resin base material 8. Of course, it is also possible to use a substrate made of an inorganic substance such as ceramics instead of the synthetic resin substrate 8, and in such a case, the metal thin film layer 9 is laminated and formed by an appropriate method.

FIG. 3 shows a second embodiment of the electrode, the electrode 1a comprising:
An adhesive 10 is formed by attaching a metal thin film layer 9 such as an aluminum foil to the surface of a sheet-shaped synthetic resin base material 8 made of a flexible and heat-resistant polyethylene terephthalate (PET) or ethylene tetrafluoride resin (PTFE). Forming a metal thin film layer 9 on the surface of the synthetic resin base material 8 directly without interposing an adhesive 10;
The conductive layer 4 is laminated thereon to have flexibility as a whole. The metal thin film layer 9 and the conductive layer 4 are electrically connected to each other so that current can be supplied from an extraction electrode 11 protruding laterally from the metal thin film layer 9.

FIGS. 4 and 5 show a third embodiment of the electrode. This electrode 1b is formed by fixing carbon powder or graphite powder on the surface of a metal electrode substrate 3 fixed to the tip of a piston rod 6. To form a conductive layer 4 by forming a carbon layer 12. It is to be noted that, other than sintering as a method for forming the carbon layer 12, a method of directly consolidating at a pressure of 30 to 50 t / cm ² is also a modification of the present embodiment.

FIG. 6 shows a fourth embodiment of the electrode, and this electrode 1c
Long fibers of carbon or graphite are woven into a sheet by plain weaving or the like, and one or a plurality of the fibers are laminated to set a desired bending hardness. That is, the electrode 1a can be used in the same form as the electrode 1a if it is flexible against bending, and can be used in the same form as the electrode 1b if it is hard. In addition, it is often difficult to maintain the shape only by weaving carbon fibers and the like,
It is considered that the space between the webs is appropriately filled with a synthetic resin.

In addition, since a sheet in which carbon or graphite long fibers are oriented in one direction and a number of them are arranged in parallel has already been provided, the sheets are laminated by crossing the orientation directions with each other by using them, and a desired thickness direction is obtained. It can also be formed to have conductivity.

Next, examples of heating and manufacturing foods 2 of various shapes using the above-described electrodes will be described below.

First, the one shown in FIG. 7 is such that a cylindrical electrode 13 having the same structure as that of the above-mentioned electrode 1 is provided coaxially with a cylindrical electrode 13 having the same structure as the above-mentioned electrode 1, and both ends thereof are opened. ,
The surimi 2 is filled between the two electrodes, and an alternating current is supplied between the two electrodes 13 and 14 by a power source 7 to heat the same, thereby producing a cylindrical bamboo wheel or the like. When the food 2 is heated, the food 2 shrinks slightly. Therefore, it is necessary to press the both ends 13 and 14 from both ends with a ring-shaped insulating plate. Further, by sequentially supplying the food 2 from one end in the axial direction of the electrode and flowing it between the electrodes 13 and 14, and discharging the food 2 from the other end, a cylindrical product can be continuously manufactured. To obtain a bamboo ring as described above.

Next, the one shown in FIG. 8 uses the flexible electrode 1a, places the food 2 around the same cylindrical electrode 14, and winds the sheet-like electrode 1a around the same. The bamboo ring is obtained by heating as described above. Here, since the electrode 1a has flexibility, it can be deformed into various shapes.

Further, what is shown in FIG. 9 sandwiches the food 2 formed flat by using two sheet-like electrodes 1a in the same manner as described above, and heats the same to obtain the starch.

By the way, the heating device having the structure shown in FIG.
Was heated, it was found that the temperature rose from the center of the food 2. Therefore, as shown in FIGS. 10 and 11, it is possible to heat the food 2 uniformly or partially preferentially as a whole by forming the electrode 1 in a radially outward multiple structure. That is, a small disk-shaped electrode 15 is arranged at the center, and a small ring-shaped electrode 17 is arranged concentrically around an outer periphery of the small electrode 15 with an insulator 16 interposed therebetween. In the same manner as in the electrode 1, a conductive layer 4 is formed on the surface of an electrode substrate 3 having a predetermined shape, and they are integrated with the insulator 16 interposed therebetween. A current can be independently supplied from the power supply 7 to each of the small electrodes 15 and 17. For example, the small electrodes 15 and 17 can be
The current is supplied alternately and with a different energizing time.
In addition, a method of supplying a current to the two small electrodes 15 and 15 and the small electrodes 17 and 17 of the opposed electrodes 1 and 1, respectively, includes a method of supplying a current between the pair of small electrodes 15 and 15 facing each other and the small electrodes 17 and 17 as described above. 17 and one electrode 1 at the crossing position
There is a method in which current is alternately applied between the small electrode 15 and the small electrode 17 of the other electrode 1, and any method can uniformly heat the food 2 or partially preferentially heat it. In addition to changing the energizing time, the food 2 can be heated by changing the amount of current.

In addition, by using the electrode 1 in which the resistance value of the conductive layer 4 on the surface in contact with the food 2 is appropriately changed according to the position of the contact surface as described above, the amount of current supplied to the food 2 is partially changed. The degree of heating can be adjusted.

12 and 13 show an embodiment of an apparatus for heating a food 2 having a fish meat surimi formed in a semi-cylindrical shape on the upper surface of a kamaboko board 19, that is, a kamaboko having a shape that is conventionally familiar. This is an example, and the electrodes arranged on the short side end of the Kamaboko board 19
1, 1 are provided with through holes 20 or recesses or notches for receiving the ends of the kamaboko 19, and when the food 2 shrinks due to heating, the piston rod 6 fixed to the electrode 1 or other pressing and moving means. The electrode 1 is moved inward so that the conductive layer 4 of the electrode 1 always contacts the food 2. The conductive layer 4 may be provided on the entire inner surface of the electrode 1, but only the portion above the through hole 20 is sufficient. Here, the amount of current flowing through the food 2 is detected,
By driving the piston rod 6 according to the value and displacing the electrode 1, it is also possible to make the desired current always flow through the food 2, and furthermore, the two electrodes 1, 1 are fixed by a spring or the like. It is also practical to bring the food 2 into contact with the pressing force.

Further, FIG. 14 shows an embodiment of an apparatus for heating a liquid food 2 in which electrodes 1, 1 are arranged on the inner wall of a container 21 so as to face each other. In this case, the electrode substrate 3 of the electrode 1
Is preferably covered with the conductive layer 4 so as not to come into contact with the food 2.

〔The invention's effect〕

According to the food heating device and the heating method of the present invention described above, the following effects are obtained.

First, by forming a conductive layer using a conductive material in which carbon or graphite powder or short fibers are supported by a resin binder at least in an electrode portion in contact with a food having conductivity, ionization is performed as in a conventional electrode material. In addition to preventing the metal from coming into contact with food, eliminating the adverse effects of electrolytic corrosion, increasing the durability of the electrodes, improving the operating efficiency of the heating device, and adjusting the electrical conductivity, It can supply enough current to generate Joule heat.

In addition, by forming the conductive layer on the surface of the electrode substrate, it is possible to use a metal, a synthetic resin, and an inorganic material as the electrode substrate, to provide the electrode at low cost, and to reduce the cost of the heating device, In addition, a shape-stable electrode or a flexible electrode can be selected according to various forms of food.

Furthermore, when the resistance value of the conductive layer on the surface in contact with the food is appropriately changed according to the position of the contact surface, the amount of current supplied to the food from the conductive layer can be adjusted in each part of the food, As a result, uniform heating or partial preferential heating can be performed, and the quality of the product can be improved, or there is a possibility of producing a new food which has not existed before.

When a conductive material having a carbon component is used as the conductive material, it is stable without being oxidized and reduced electrochemically, and the durability can be further improved.

In addition, by using an electrode in which a plurality of small electrodes in which a conductive layer is formed using a conductive material made of a substance that does not ionize at least at a portion in contact with a food having conductivity, an electrode is used in which a plurality of small electrodes are assembled via an insulator, so that resistance of the conductive layer As in the case of changing the value, it is possible to adjust the amount of current supplied from each small electrode to the food in each part of the food, thereby enabling uniform heating or partial priority heating and a small electrode constituting one electrode It is also possible to pass an electric current between them, and it is possible to brown the end face of the food in contact with the electrode, etc.
This makes it possible to diversify the manner of use.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a food heating apparatus using an electrode according to the first embodiment of the present invention, FIG. 2 is an enlarged sectional view of the same electrode, and FIG. FIG. 4 is an enlarged sectional view, FIG. 4 is a perspective view of an electrode of a third embodiment of the present invention, FIG. 5 is a sectional view of the same, FIG. 6 is a partial perspective view of an electrode of a fourth embodiment of the present invention, FIG. FIG. 8 is a perspective view of an apparatus for heating a cylindrical food using the electrode of the first embodiment, and FIG. 8 is a diagram showing a combination of the electrode of the first embodiment and the electrode of the second embodiment for heating a cylindrical food. FIG. 9 is a simplified cross-sectional view of an apparatus for heating flat food using the electrode of the second embodiment, FIG.
10 is a perspective view showing a modification of the electrode of the first embodiment, FIG. 11 is a sectional view of the same, FIG. 12 is an abbreviated perspective view of a device for heating the kamaboko, FIG. 13 is a sectional view of the same, FIG. 14 is an oblique perspective view of an apparatus for heating a liquid food, and FIG. 15 is a longitudinal sectional view of a conventional surimi heating apparatus using electrodes. 1,1a, 1b, 1c: electrode, 2: food, 3: electrode substrate, 4: conductive layer, 5:
Cylindrical body, 6: piston rod, 7: power supply, 8: synthetic resin base material, 9:
Metal thin film layer, 10: adhesive, 11: extraction electrode, 12: carbon layer, 13: cylindrical electrode, 14: cylindrical electrode, 15: small electrode, 16: insulator, 17: small electrode, 18: switch, 19: Kamaboko, 20: Through hole, 21: Container.

Continuation of the front page (72) Inventor Kiyoshi Kondo 5-3-18 Himejima, Nishiyodogawa-ku, Osaka-shi, Osaka Inside Fan Chemical Industry Co., Ltd. (72) Inventor Tadaaki Aoki 3-6-1, Kutaro-cho, Chuo-ku, Osaka-shi, Osaka No. Toyo Aluminum Co., Ltd. (56) References JP-A-3-103161 (JP, A) Jiko 9-13607 (JP, Y1) Jiko 7-6516 (JP, Y1) (58) Fields investigated (Int.Cl. ⁶ , DB name) A23L 1/01 A23L 1/325 A23L 1/10 A47J 27/00-27/14 H05B 3/14

Claims (7)

(57) [Claims] An electrode formed by forming a conductive layer on a surface of an electrode substrate using a conductive material in which carbon or graphite powder or short fibers are supported by a resin binder at least in a portion in contact with a conductive food. A food heating device which is arranged in contact with the food and heated by Joule heat generated by supplying an electric current from the electrode into the food. 2. The food heating apparatus according to claim 1, wherein the resistance value of the conductive layer on the surface in contact with the food is appropriately changed according to the position of the contact surface. 3. An electrode in which a plurality of small electrodes having a conductive layer formed by using a conductive material made of a non-ionizable substance at least in a portion in contact with a food having conductivity has a plurality of small electrodes assembled via an insulator in contact with the food. A food heating device characterized in that the food is heated by Joule heat generated by supplying an electric current into the food from the electrode. 4. The food heating apparatus according to claim 3, wherein said conductive layer is formed on a surface of an electrode substrate. 5. The food heating apparatus according to claim 3, wherein the small electrode is formed using only the conductive material. 6. The food heating device according to claim 3, wherein the conductive material is a conductive material having a carbon component. 7. A food having conductivity is brought into contact with two or more conductive layers formed by using a conductive material in which carbon or graphite powder or short fibers are supported by a resin binder on the surface of an electrode substrate. A method for heating a food, comprising supplying an electric current to the food through a layer to generate Joule heat and heating the food.