JP2001017131A - Heat sterilizer capable of uniform heating and intended for high-viscosity and ingredient-containing food - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject heat sterilizer having such a scheme that a food material is advanced straight into a space of square section formed between a pair of electrode plates, and concurrently an electric current is allowed to flow between the electrode plates to heat-sterilize the food material by the heat thus generated, thereby enabling the object food material to be heated uniformly with slight pressure loss without destruction of its texture. SOLUTION: This heat sterilizer has such a scheme that, inside a metallic pipe 14 having a predetermined length and joints on both ends, a pair of electrode plates 15 are made to stand against each other in parallel to the axis of the metallic pipe 14, wherein the metallic pipe 14 and the electrode plates 15 are integratedly formed together with a molding rubber 16. A fluid food material is advanced straight into the space of square section defined between the electrode plates 15, and concurrently an electric current is allowed to flow between the electrode plates 15 to heat-sterilize the food material by the Joule heat thus generated. Thereafter, it is preferable to cool the food material thus heat-sterilized by making a cooling medium to flow into an agitating rotor and using a double-jacket-type scraped surface heat exchanger having the function of cooling through both inner and outer sides.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for heating and sterilizing high-viscosity foods such as miso, wasabi, ginger, jam, puree-like foods, and other foods containing curries, stews, meat sauces and the like. It is about.

[0002]

2. Description of the Related Art As a heat sterilizer for food described above,
1) tube type heat exchanger, 2) scraping type heat exchanger,
3) Joule energization heating method is used. The heat sterilizer using the tube heat exchanger of 1) adopts a multi-tube one-pass system in order to reduce pressure loss, and to reduce the diameter of the heat exchange pipe to 10 in order to achieve uniform heating.
Either use a small diameter of less than mm or insert a static mixing mixer in the pipe. In this method, the contact area with a high-viscosity material is large, it does not reach complete heating, the accuracy of temperature control is poor,
There are problems such as the inability to wash and the possibility of a short path.

[0003] In the scraping type heat exchanger 2), the composition of miso or the like is broken by heating and stirring, and as a result, the miso or the like becomes soft and sticky. There are problems such as breakage or burning odor, and the fact that the temperature of the heat transfer wall surface is high, so that it takes a long time until the outlet temperature reaches the set temperature and stabilizes.

[0004] The heating of the above 1) and 2) is indirect heating using steam or hot water as a heat medium, and the temperature is controlled by an outlet temperature feedback control method. The heating method of 3) is disclosed in Japanese Patent Application Laid-Open No. Hei 7-39320, but a combination of two cylindrical electrodes in a cylindrical heating unit and a vertical one is used. It is used diagonally in view of the problem of transporting solids.
In this case, because the ring electrode is used, electricity does not flow uniformly to the processed material, so that high-viscosity materials such as miso cannot be heated uniformly. In addition, since the electrode area is small and separated, a relatively high voltage is required, and when a delicate product (eg, miso, cream, etc.) is processed, sparks tend to occur, which is not suitable.

[0005] Further, as a cooling device for a heat-treated food, 1) a tube type heat exchanger is used for a high viscosity material;
2) For high-viscosity materials and foods containing ingredients, a scraping type heat exchanger is used. This cooler also has the same problem as the above-described heating unit, and in particular, there is a problem that the composition such as miso is broken by heating and stirring, so that the miso becomes soft and sticky. In addition, there is a problem in that the mixed solid is broken by the stirring action in the solid-liquid mixture. Furthermore, if the number of revolutions of the rotor is reduced in order to solve these problems, a problem arises in that uniform cooling cannot be performed.

[0006]

SUMMARY OF THE INVENTION In view of the problems of the prior art, in a heater for food with high viscosity and ingredients, it is necessary to enable uniform heating of the processed product and to improve the accuracy of temperature control. Reducing pressure loss, CI
P enables cleaning, eliminates structures with agitation and shearing action, does not destroy the composition of the processed material, reduces sparking, and in a cooler, sets the rotation speed of the rotor to 30 rpm. A heat sterilization device that enables uniform cooling of the processed material even at the following low speeds, slows down the number of rotations of the rotor and can cool without destroying the composition of the processed material, and enables the above heating and cooling. The purpose is to provide.

[0007]

Means for Solving the Problems (1) A pair of electrode plates are opposed inside a metal pipe having a predetermined length and having connection portions at both ends in parallel with the axis of the metal pipe. The metal pipe and a pair of electrode plates facing each other are integrally molded with molding rubber, and a current is applied between the electrode plates while the fluid food material advances straight into a rectangular space formed between the opposed electrode plates. This enables uniform heating sterilization by the generated Joule heat. (2) The liquid food material passed through the rectangular space formed between the opposed electrode plates in the heat sterilization apparatus of (1) and sterilized by heat is cooled from both the inside and the outside of the stirring rotor. The cooling was performed using a double-jacketed scraping heat exchanger. (3) In the above-mentioned devices (1) and (2), the programmable controller 13 preliminarily stores the frequency of the liquid-feed pump inverter 10, the electric signal of the inlet temperature, the name of the non-processed object, and the data relating to the heating temperature. Input, and the provided power can be predicted, and the provided power can be set from the beginning of operation. (4) The opposing electrode plate is formed by providing a conductive ceramic sprayed coating on a current-carrying metal substrate and impregnating voids of the sprayed coating with a heat-resistant material. (5) The electrode plate is made of only Ti or the substrate is made of Ti,
Was provided with a conductive ceramic sprayed coating, and Teflon was coated thereon. (6) The electrode plate is made of a substrate made of Ti, the surface of which is coated with platinum.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 shows a flow of a miso pasteurization cooling system according to the present invention.
In FIG. 1, reference numeral 1 denotes a liquid sending pump, which is connected to a hopper 2 provided with a pushing screw 3 at an inlet thereof. The raw material in the hopper 2 is sent to the heat sterilizer 5 via the sanitary pipe 4 by the liquid feed pump 1.

At the outlet of the heat sterilizer 5, a temperature sensor 6 is provided.
Is installed, and the temperature measured here is a temperature controller 7
Is supplied to the thyristor regulator 8 so that the temperature becomes a preset temperature, and an electric power of an appropriate value is supplied from the insulating transformer 9 to the electrode plate of the heating sterilizer 5. In order to speed up the time required to reach the set heating temperature at the time of starting operation, necessary data (see below) are input to the programmable controller 13 in advance, and an instruction is given to provide a calculated value output for a certain time at the time of starting. give.

As necessary data to be input to the programmable controller 13 in advance, an electric signal of the frequency (flow rate) and the inlet temperature of the liquid feed pump inverter 10 is taken into the programmable controller 13, and the name of the processed material (specific gravity, specific heat), heating Input data related to temperature as necessary data. Then, after a certain period of time, the control is automatically switched to the feedback control. The heated processed material is sent to the scraping type heat exchanger 12 in the cooling step after passing through the holding tube 11 and cooled.

FIG. 2 shows the details of the heat sterilizer 5. FIG.
(A) is a modularized heat sterilizer 5
, (B) is a right side sectional view of (a), and (c) shows details of a power feeding portion to the electrode plate. In FIG. 2, reference numeral 14 denotes a metal pipe having a predetermined length in advance, and as described later, is connected with flange portions 14a at both ends to form a plurality of modules so as to obtain a desired processing capacity. It can be connected and used. Reference numeral 15 denotes an electrode plate, which is installed parallel to the axis of the metal pipe 14 and symmetrically opposed to the axis. The metal pipe 14 and the electrode plate 15 are integrally molded with a molded rubber 16. Reference numeral 17 denotes a bolt having one end fixed to the electrode plate 15, which is fixed to the metal pipe 14 by a resin seat plate 18 and a nut 19. The bolt 17 constitutes a power supply portion to the electrode plate 15 and is shown in FIG.
In the example, two pairs of bolts 17 are mounted in the axial direction. By providing two pairs of bolts, power can be supplied to the electrode plate 15 from the two bolts 17 and heated when a large processing capacity is required. The bolts 17 also have a function of positioning the electrode plate 15 prior to integrally forming the module for heat sterilization with the molded rubber 16.
Thus, after the electrode plate 15 is correctly positioned with respect to the metal pipe 14, a molding core is fitted inside, and a molding rubber 16 is filled between the metal pipe and the electrode plate to be integrated. The unit integrated in this way is a unit (module)
And use it as necessary.

The electrode plate 15 has a conductive ceramic layer formed by thermal spraying and has a porous surface. Therefore,
By impregnating the surface voids with a heat-resistant material that is harmless for food hygiene, it is possible to improve the water repellency of the electrode surface, increase the separability of liquid products and paste-like products from the electrode plate, and improve workability. it can.

Examples of such heat-resistant materials include synthetic resins such as cellulose resins, fluorine resins, silicone resins, olefin resins, and polyester resins, and baked products such as zirconia and titania sol. . The filling of the electrode surface voids with such a synthetic resin is performed by immersing the electrode on which the conductive ceramic layer has been formed in advance in an organic solvent solution or aqueous dispersion of these resins,
Drying and, if necessary, heat treatment can be performed.

Since the surface of the electrode plate is impregnated with a ceramic layer and a heat-resistant material thereon, metal ions are eluted even when a low voltage of 200 V or less and a low frequency power supply of 50/60 Hz are used. Food can be heat-sterilized safely without causing electrical corrosion. (Miso and egg products must be low voltage, sparks easily and cannot be heated.)

The heat sterilizer 5 thus formed
In FIG. 2, the passage through which the material such as miso to be heat-sterilized passes has the shape indicated by reference numeral 20 in FIG. FIG. 2C shows an example of a method of supplying power to the electrode plate 15 of the heat sterilizer 5, wherein a crimp terminal 21 is fixed to the bolt 17 and connected to a power supply (not shown) via a waterproof connector 22. FIG. 3 shows a configuration of an insulating pipe for connecting the modularized heat sterilizer 5 described in FIG. 2 to a sanitary pipe or the like having a circular cross section. Heat sterilizer 5 is packing 2
3 via an insulating pipe 24. The insulating pipe 24 has a metal pipe 25 on the outside and a pipe 25
Inside, a molding rubber 26 is formed so as to smoothly change from a circular opening 27 to an opening 28 having a rectangular cross section (FIG. 4). The square opening 28 has the same shape as the square passage 20 of the heat sterilizer 5, and the circular opening 27 has a round shape equal to a circular cross section of a sanitary pipe or the like.

By using such a heat sterilizer 5 by appropriately connecting it via a number of flanges, if water and salts or minerals are present, electric heating can be carried out. It can be used for heat sterilization of food. Due to self-heating, the temperature gradient required for indirect heating such as steaming, baking and boiling is unnecessary, and uniform heating is achieved.
Irrespective of the thermal conductivity, foods with poor thermal conductivity, such as proteins, and high-viscosity fluid foods, which hardly cause convection, can be rapidly heated. Since the heat generation can be controlled by the amount of electricity, precise temperature control is possible. High energy efficiency. By appropriately selecting the frequency, better heating can be achieved.

FIG. 5 is a sectional view of the scraping type heat exchanger 12 for cooling in FIG. 1, and FIG. 6 is an enlarged sectional view taken along line AA of FIG. After the food heated by the above-mentioned heat sterilizer 5 passes through the holding tube 11, it is cooled by the scraping type heat exchanger 12. In FIG. 5, 12a is a cylinder body, 12b is a rotor provided with a scraper 29, 1
2c is a cylinder outer cylinder. Numeral 30 denotes a heat-sterilized processed material which exchanges heat when passing through an annular passage 31 between the cylinder body 12a and the rotor 12b, where the processed material is cooled. Reference numeral 32 denotes a refrigerant through which the refrigerant flows inside and outside the annular passage 31. The refrigerant is fed from a cooling water nozzle 33 provided at the center of the scraping type heat exchanger 12 and
It is returned through an annular passage 28 between 2b and the cooling water nozzle 33. In addition, in the above-mentioned example, it was explained that the opposing electrode plate was provided with the conductive ceramic sprayed coating on the current-carrying metal substrate, and the heat-resistant material was impregnated into the voids of the sprayed coating.

The electrode plate is not limited to this, and the following can be applied. 1) A substrate using only Ti as a current-carrying metal substrate. 2) A conductive ceramic is provided with a sprayed coating on the surface of Ti, which is a metal substrate for electricity, and Teflon is impregnated thereon. 3) Teflon coated on the surface of Ti which is a current-carrying metal substrate. 4) A metal coated with platinum coated on the surface of Ti which is a current-carrying metal substrate.

[0019]

According to the present invention, a modular heat-sterilizer 5 having a predetermined length integrally formed with an opposing electrode plate inside a metal pipe is used. The use of a plate with the flat plates facing each other enables a single-tube one-pass heating process. With such a configuration, since the processing object flows through the passages in the electrode plates arranged in parallel, the electric current is uniformly heated and the processing object can be uniformly heated. Evenly energized and heated, there is no temperature unevenness,
Temperature control became easier, and the accuracy of temperature control was further improved. Since connectable and modularized heat sterilization is used, the passage area of the processed material can be designed to be large according to the capacity, and the pressure loss can be reduced. Since the passage of the processed material was only a square hole and had no other stirring parts, cleaning was easy and CIP cleaning became possible. Since it only passes through the square hole, it does not receive any action such as kneading and mixing. Also, since there is no agitation or shearing structure, the composition of the treated product is not destroyed. Since it can be energized at a low voltage of 200 V or less on average,
Stable operation is possible and spark is less likely to occur. In addition, a double-jacket scraping type heat exchanger is used for cooling, and a refrigerant is also flown into the stirring rotor, and the cooling is performed from both the inside and outside. The object can be cooled uniformly. In addition, since the number of rotations of the rotor can be reduced, cooling can be performed without destroying the composition of the processed material. The electrode plate may be made of only Ti. However, if a chemically inert conductive ceramic coating layer is provided on the surface of the electrode plate such as Ti, the electrochemical contact between the metal substrate and the food is eliminated, and the elution of metal ions is performed. The discoloration of the food due to is prevented.
Further, if a heat-resistant material such as a synthetic resin is further included in the voids of the conductive ceramic film layer, the water-repellent action of the synthetic resin or the like improves the separation of the liquid food and the paste-like food from the electrode, thereby improving workability. The performance is improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a flow of a miso pasteurization cooling system.

FIG. 2 is a modularized heat sterilizer.

FIG. 3 shows an insulating pipe used for a connection portion of the heat sterilization apparatus with another pipe and a related configuration thereof.

FIG. 4 is a detailed view of an insulating pipe at a connection portion.

FIG. 5 is a longitudinal sectional view of the cooling device.

FIG. 6 is an enlarged sectional view taken along the line AA of FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Liquid-feeding pump 2 Hopper 3 Insertion screw 4 Sanitary pipe 5 Heat sterilizer 6 Temperature sensor 7 Temperature indicating controller 8 Thyristor regulator 9 Insulation transformer 10 Inverter 11 Holding tube 12 Scraping heat exchanger 12a Cylinder body 12b Rotor 12c Cylinder outer cylinder 13 Programmable controller 14 Metal pipe 15 Electrode plate 16 Molded rubber 17 Bolt 18 Resin seat plate 19 Nut 20 Passage 21 Crimp terminal 22 Waterproof connector 23 Packing 24 Insulation pipe 25 Pipe 26 Molded rubber 27 Circular opening 28 Square opening 29 Scraper 30 Treated object 31 Annular passage 32 Refrigerant 33 Cooling nozzle

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Muneyuki Tada 552-1 Midoricho Hirota, Mihara-gun, Hyogo Prefecture Inside Izumi Food Machinery Co., Ltd. Inside Food Machinery (72) Inventor Takeo Sugita 4-1-1 Aiomachi, Yao-shi, Osaka Toyo Aluminum Co., Ltd. Aluminum foil laboratory and development department F term (reference) 4B021 LA41 LA43 LP04 LW02 LW04 LW07 LW09 LW10

Claims (6)

[Claims] 1. A pair of electrode plates are opposed inside a metal pipe having a predetermined length and having connection portions at both ends in parallel with the axis of the metal pipe, and opposed to the metal pipe. A pair of electrode plates are integrally molded with molded rubber, and while a fluid food material goes straight into the rectangular space formed between the opposing electrode plates, electricity is supplied between the electrode plates and heated by the generated Joule heat. A heat sterilization apparatus for foods containing high viscosity and ingredients that can be uniformly heated, which is sterilized. 2. A heat-disinfecting apparatus according to claim 1, wherein a fluid food material passed through an adiabatic rectangular space formed between the opposed electrode plates and heat-sterilized is passed through a cooling rotor into a stirring rotor, A heating and sterilizing apparatus for high-viscosity foods and foods containing ingredients that can be uniformly heated, wherein cooling is performed by a double-jacket scraping-type heat exchanger that cools from both the inside and the outside. 3. The programmable controller (13) receives in advance the frequency of the liquid feed pump inverter (10), an electrical signal of the inlet temperature, the name of the object to be processed, data relating to the heating temperature, etc., and operates the controller. 4. The heat sterilizing apparatus for high-viscosity foods and foods containing ingredients that can be uniformly heated according to claim 1, wherein the supplied power can be set from the beginning. 4. The opposed electrode plate is provided with a conductive ceramic sprayed coating on a current-carrying metal substrate, and a gap portion of the sprayed coating is impregnated with a heat-resistant material.
The heat sterilization apparatus for a high-viscosity food and food containing ingredients capable of being uniformly heated according to claim 2 or 3. 5. The high-viscosity food product according to claim 1, wherein the electrode plate is made of only Ti or the substrate is made of Ti, and a conductive ceramic sprayed coating is provided on the surface of the Ti, and Teflon is coated thereon. Heat sterilizer for food with ingredients. 6. The apparatus according to claim 1, wherein the electrode plate is made of a substrate made of Ti and coated on its surface with platinum.