JP2002017244A - Method for heating shellfishes - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for heating shellfishes, by which the shellfishes such as oysters can be heated, while the surfaces of the shellfishes are maintained in a state close to a living state, thereby enabling to hold a texture similar to those of living shellfishes. SOLUTION: This method for heating the shellfishes is characterized by supplying an electric power from electrodes 11, 12 to oyster-mixed water 16 comprising oysters 14 and water 15 to heat the oysters 14 with Joule heat generated with an electric current flowed in the oysters. The electric power is applied to the oyster-mixed water 16 in a state that the electric resistance of the oysters 14 is smaller than the electric resistance of the water 15. When the oysters 14 are heated with the Joule heat generated with the applied electric current, the oysters can thereby be heated, while the temperature of the heated water 15 is maintained at a lower temperature than the temperature of the heated oysters 14 to cool the surfaces of the oysters 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of heating shellfish for heating edible mollusks, such as oysters, covered with shells.

[0002]

BACKGROUND OF THE INVENTION Shellfish, which are edible mollusks, include oysters,
There are clams, clams, scallops, etc., and the edible part of the body is covered with a calcareous outer shell, or shell. There are bivalves and snails depending on the shape of the shell.

[0003] In addition to oysters, oysters such as shellfish include oysters such as oyster oysters and oysters. And Fresh oysters that do not contain bacteria can be served as raw food, but even fresh oysters that contain bacteria need to be cooked and served for eating.

[0004] Bacteria contained in oysters are caused by bacteria contained in seawater entering the oysters, especially the internal parts, and the cleanliness of the oysters is determined by the surrounding oysters. Will depend on the cleanliness of the seawater. Therefore, even if fresh oysters have just been landed from the sea, such as in a farm, if bacteria are contained in the seawater, the bacteria may enter the built-in water along with the seawater and adhere to the oysters. Even if the seawater is washed, the bacteria in the body cannot be treated, and it is not preferable to use the oyster itself for food as it is.

[0005] Therefore, immediately after landing, the bacteria contained in the oysters are inspected to determine whether the oysters are used for raw food or for cooking. If it is contained in the body, it will be used for cooking for cooking.

[0006]

Even if bacteria are contained in oysters, they can be used for food as long as the bacteria can be treated. Bacteria can be treated and removed by heating to about 70 ° C or higher, so attempts have been made to boil oysters with steam, but when boiled, the volume of oysters is about half that of before the boil. And the yield is about 50%.

[0007] Such problems are not limited to oysters, but also apply to other shellfish such as scallops.

An object of the present invention is to make it possible to heat shellfish such as oysters while keeping the surface of the body to be eaten close to raw.

Another object of the present invention is to maintain a texture close to that of a raw food even when shellfish such as oysters are heated.

[0010]

According to the method for heating oysters of the present invention, an electric power is supplied from an electrode to mixed water containing shellfish such as oysters and water, and the shellfish is heated by Joule heat generated by an electric current flowing through the shellfish. Is heated to generate heat.

In the method for heating shellfish of the present invention, electric power is supplied to mixed water having water and shellfish set to an electric resistance higher than the electric resistance of the body of a shellfish such as oyster, and the mixture is generated by energization. The temperature at which the body portion of the shellfish generates heat by Joule heat is heated to a temperature higher than the temperature at which water generates heat.

According to the method for heating shellfish of the present invention, electric power is supplied from an electrode to a mixed water containing shellfish such as oysters and fresh water, and the shellfish is heated and heated by Joule heat generated by an electric current flowing through the shellfish. It is characterized by the following.

[0013] The method for heating shellfish of the present invention comprises the steps of: supplying power from an electrode to mixed water containing shellfish such as oysters and water, and heating the shellfish by heating it with Joule heat generated by energization; It is characterized in that the shellfish is heated while the surface temperature of the shellfish is cooled while the heat generation temperature of water is lower than that of the shellfish.

The method of heating shellfish according to the present invention is characterized in that the shellfish is immersed in water sterilized with ozone or the like. Further, the method for heating shellfish of the present invention is such that, while flowing the mixed water into the pipe, electric power is supplied to the mixed water from an electrode provided on the pipe to continuously heat the shellfish. Wherein, while transporting the shellfish by a conveyor in a container in which the mixed water is stored, power is supplied to the mixed water from an electrode provided in the container, and the shellfish is continuously heated. It is characterized by the following.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing a heating apparatus embodying a method for heating shellfish according to one embodiment of the present invention. This heating apparatus has a rectangular parallelepiped heating vessel 10 having an open upper end. Further, plate-like electrodes 11 and 12 are provided on the inner surfaces of the two side walls facing each other. Each electrode 1
The power supplies 1 and 12 are connected to a power supply unit 13 from which electric power such as a commercial power supply or a high-frequency power supply is supplied to the electrodes 11 and 12.

In the heating vessel 10, oyster mixed water 16 having peeled oysters 14 and water 15 as edible mollusks to be heated is supplied. Therefore, when power is supplied from the power supply unit 13 to the electrodes 11 and 12, an electric current flows through the oyster mixed water 16 in contact with the electrodes 11 and 12, and Joule heat is generated in the oyster mixed water 16 so that the oysters 14 Heated.

When the oyster mixed water 16 is heated by Joule heat, the current flowing through the oyster 14 of the oyster mixed water 16 is made larger than the current flowing through the water 15 so that the heating temperature of the oyster 14 is higher than that of the water 15. Can be set to a high temperature.

When the oyster 14 is energized, the oyster 14 itself generates heat, so that the oyster 14 can be heated, and the inside of the oyster 14 has a higher temperature than the surface portion. In particular,
Since the water content of the seawater in the oyster's built-in portion is high, that portion has a higher temperature rise time than the other portions and becomes hotter than the other portions.

In order to make the current flowing through the oyster 14 different from the current flowing through the water 15 so as to make the respective heating times different, the electric resistance between the oyster 14 and the water 15 must be different. The salt concentration of seawater is about 3%. If the salt concentration of the water 15 is made lower than this, or if fresh water is used, the electric resistance of the water 15 becomes larger than the electric resistance of the oyster 14, and the oyster mixed water Of the 16, the current flowing through the oyster 14 is larger than the current flowing through the water 15, and the Joule heat generated in the oyster 14 is larger than the Joule heat generated in the water 15. As a result, the temperature of the oysters 14 rises faster than that of the water 15, and the heating temperature when the power supply is stopped is higher in the oysters 14 than in the water 15.

As described above, when the oyster mixed water 16 is heated so that the temperature of the oyster 14 is higher, the water 15 having a lower temperature than the oyster 14 is covered around the oyster 14, so that the surface of the oyster 14 The oysters 14 are cooled so that they do not become hotter than the inside, and the surface of the oysters 14 can be brought into a state close to raw oysters.

FIGS. 2 and 3 are diagrams showing another example of a heating apparatus embodying the heating method of the present invention. In the above-described case, the heating of the oyster mixed water 16 is a batch process. , Continuous processing.

This heating device has a heating pipe 20 made of an insulating material such as a resin having a rectangular cross section, and electrodes 21 and 22 are provided on two inner faces of the pipe 20 facing each other. Each electrode 2
The power supply unit 13 is connected to the power supply units 1 and 22 in the same manner as described above. Joint portions 23 and 24 are attached to both ends of the pipe 20, and the oyster mixed water 16 is heated by a guide pipe or the like, with one joint portion 23 being on the upstream side and the other joint portion 24 being on the downstream side. It is supplied into the pipe 20.

In a heating device of this type, a plurality of heating pipes 20 may be connected by joints 23 and 24. Further, the cross-sectional shape of the heating pipe 20 may be a circular cross-section, and a ring-shaped electrode is used as the electrodes 21 and 22 without using a plate-shaped electrode.
The electrodes may be provided on the pipe 20 at predetermined intervals.

When the oyster 14 is heated by flowing the oyster mixed water 16 into the heating pipe 20, the energizing time is set at the pipe 2.
It will be set by the flow rate flowing through zero.

FIG. 4 is a view showing still another example of a heating apparatus embodying the heating method of the present invention. This heating apparatus has a container 30 for containing the oyster mixed water 16, and this container 3
In 0, electrodes 31 and 32 are arranged in parallel, and these electrodes 31 and 32 are connected to the power supply unit 13. A transport conveyor 33 is provided for continuously transporting the oysters 14 in the container 30, and a loading conveyor 34 for transporting the oysters 14 to the transport conveyor 33, Oyster 14 in container 30
The container 30 is provided with an unloading conveyor 35 for unloading from the outside.

Each of the conveyors 33 to 35 constitutes a conveying means. Each of these conveyors has a rotating body such as a roller and a belt wrapped around the rotating body. It is formed of a material having extremely high electric resistance, such as nonwoven fabric, paper, or resin, or an insulating material. When a belt made of a material having an insulating property such as a resin is used, it is preferable to use a belt formed in a mesh or mesh shape so that an electric current flows through the gap.

In each of the above-described embodiments, it is preferable to sterilize the oyster mixed water with ozone or the like. Ozone sterilization may be performed by treating water before mixing with oysters, or may be performed after mixing. After the heat treatment, the oysters may be immersed in ozone-sterilized water.

[0029]

EXAMPLES Oyster heating experiments were carried out under various heating conditions using a heating vessel 10 as shown in FIG. 1, and data as shown in Tables 1 and 2 were obtained. As the heating container 10, a size having a width of 95 mm on each of four sides was used, and a commercially available oyster was used for raw food. The weights of the oyster 14 and the water 15 charged into the heating vessel 10 are as shown in Table 2, respectively. The tip of the temperature sensor was inserted into the oyster 14, and the tip of the temperature sensor was immersed in water. Table 1 shows the results of measuring the energizing time until the temperature of the water 15 becomes about 75 ° C. and the temperature of the water 15 at that time.

After the energization is completed, the oysters 14 are intercepted, the heated oyster mixed water 16 is separated into oysters 14 and water 15, and the respective yields are calculated from the weight changes of the oysters and water before and after heating. Table 2 shows the results. In addition, the current value in Table 1 shows the value immediately before the end of energization.

As shown in Table 2, as a comparative example, the weight change of the oyster before and after heating when the oyster was boiled with steam until the temperature of the oyster reached 75 ° C., ie, the yield was measured.

According to the experimental results, it was found that when the oyster mixed water 16 was heated with Joule, the weight loss of the oysters was smaller and the yield was improved as compared with the case of boiling. In addition, when boiled, the temperature inside the oyster is 7
When the temperature reached 5 ° C., the temperature of the oyster surface was higher than that, and the discoloration of the oyster surface was more remarkable as compared with the case of Joule heating.

On the other hand, when joule heating was performed, the surface of each of them had little change, and was close to raw oysters, and the texture was closer to raw oysters than when boiled.

A comparison between the case where tap water, that is, fresh water is used as the water 15 and the case where salt water is used is as follows.
When fresh water was used, the temperature of the water 15 at the end of heating was lower than the temperature of the oyster 14 as compared with the case where salt was included. The reason is that the higher the salt concentration contained in the water 15, the lower the electric resistance of the water 15 becomes than the electric resistance of the oyster 14. Water 1 than flowing current
It is presumed that the current flowing through 5 is larger, and the heat generated by Joule heat is higher in water 15 than in oyster 14.

Therefore, when heating the oyster 14 so that the temperature of the oyster 14 is higher than the temperature of the water 15, the water 15 having a salt concentration lower than the salt concentration of seawater is used as the water 15. It is preferable to use it, and it is more preferable to use fresh water. In this way, when the oyster 14 is heated so that the temperature of the water 15 is lower than the heating temperature of the oyster 14, the oyster 14 mainly has a high internal temperature, and the surface of the oyster 14 Will be cooled. Thereby, the oyster 14 can be sufficiently heated and the surface can be prevented from being overheated, so that the surface of the oyster 14 has an appearance and a texture close to that of a raw oyster. In addition, as shown in Table 2, the yield was better in fresh water than in water containing salt.

[0036]

[Table 1]

[0037]

[Table 2]

The present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the scope of the invention.

For example, in the illustrated case, the oysters are heated with the oysters being stripped, but the oysters may be heated with the shells attached. In the embodiment, the oysters are heated, but the food to be heated is not limited to oysters, such as clams and scallops, as long as they are edible mollusks covered with shells. But it is good.

[0040]

According to the present invention, it is possible to reliably heat the inside of a body portion of a shellfish such as oysters while preventing overheating of the body portion.
The inside can be heated more sufficiently than the surface of the shellfish. Since the oysters can be heated while the surface of the shells is cooled by water, the surface of the shells after heating can be made to look almost raw. It is possible to suppress a decrease in the weight of the shellfish after the heating and to increase the yield. The heated shellfish can have a texture similar to that of a raw fish.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a heating apparatus embodying a method for heating shellfish according to an embodiment of the present invention.

FIG. 2 is a sectional view showing another example of the heating device.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a sectional view showing still another example of the heating device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Heating container 11,12 electrode 13 Power supply unit 14 Oyster 15 Water 16 Oyster mixed water 20 Heating pipe 21,22 Electrode 23,24 Joint part 30 Container 31,32 Electrode 33-35 Conveyor

Claims (7)

[Claims] The present invention relates to a shellfish, wherein an electric power is supplied from an electrode to a mixed water containing shellfish such as oysters and water, and the shellfish is heated and heated by Joule heat generated by an electric current flowing through the shellfish. Heating method. 2. An electric power is supplied to mixed water having water and shellfish set to an electric resistance higher than that of a shell portion of shellfish such as oysters, and the shellfish shell is generated by Joule heat generated by energization. A method for heating shellfish, comprising heating a temperature at which a portion generates heat to a temperature higher than a temperature at which water generates heat. 3. A shellfish, comprising: supplying power from an electrode to mixed water containing shellfish such as oysters and fresh water; and causing the shellfish to generate heat by Joule heat generated by an electric current flowing through the shellfish, thereby heating the shellfish. Heating method. 4. When an electric power is supplied from an electrode to mixed water containing shellfish such as oysters and water, and the shellfish is heated by Joule heat generated by energization and heated, the temperature of the water is higher than the heat generation temperature of the shellfish. And heating the shellfish while cooling the surface of the body of the shellfish while maintaining the heat generation temperature of the shellfish at a low temperature. 5. The method for heating shellfish according to claim 1, wherein the shellfish is immersed in water sterilized with ozone or the like. 6. The method for heating a shellfish according to claim 1, wherein the mixed water is supplied to the mixed water through an electrode provided in the pipe while flowing the mixed water into the pipe. A method of heating shellfish, wherein the shellfish is continuously heated. 7. The shellfish heating method according to any one of claims 1 to 5, wherein the shellfish is provided in the container while conveying the shellfish by a conveyor in a container containing the mixed water. A method for heating shellfish, wherein electric power is supplied to the mixed water from an electrode to continuously heat shellfish.