JP6802001B2 - Fish quenching device, fish quenching method, fish cooling method, and cooled fish manufacturing method - Google Patents

Description

The present invention relates to a fish quenching apparatus and a quenching method.

Large-sized fish such as tuna, yellowtail, amberjack, bonito, and salmon are caught, drained and their internal organs removed at an offshore workshop, and then placed in an icebreaker-filled container (pickled in ice) and cooled. While being landed. After being landed, the part from which the internal organs have been removed is trimmed and washed in the processing plant on land. Tuna and the like are dipped again in an icebreaker-filled container and cooled for half a day or one day. In an icebreaker-filled container, cold seawater is first produced by adding salt to the icebreaker in the container. After the tuna and the like are put into cold seawater, the inside of the container is further cooled by adding fresh water or increasing salt. As for a method for cooling fish, a technique has been proposed in which cold water is circulated to bring live fish to a low temperature state and the live fish are transported while alive (see, for example, Patent Documents 1 to 3).

Japanese Unexamined Patent Publication No. 2004-249787 Japanese Unexamined Patent Publication No. 6-113696 Japanese Unexamined Patent Publication No. 3-139229

In the production process of tuna and the like, it is desirable to cool it rapidly in order to maintain its quality and freshness. However, it is not easy to cool a large fish such as tuna to the center. In the cooling process of tuna soaked in dove, the heat conduction inside the tuna affects the cooling rate, so the temperature of the cold seawater in the container must be lowered in order to cool the inside more rapidly. When the temperature of the cold seawater in the container is lowered, the fish itself may freeze, and there is a concern that the freezing will deteriorate the freshness.

Therefore, an object of the present invention is to provide a technique for rapidly cooling fish to maintain its freshness.

In order to solve the above problems, the present invention has decided to flow sherbet-like ice in a container for holding fish and inject sherbet-like ice into a portion from which the internal organs of the fish have been removed.

Specifically, the present invention is a fish quenching apparatus, in which sherbet-like ice is injected into a container filled with sherbet-like ice to hold the fish and a portion of the container from which the fish's internal organs have been removed. Means and prepare.

In the above-mentioned fish quenching device, by injecting sherbet-like ice (hereinafter, also referred to as sherbet ice) into the part where the internal organs of the fish have been removed, the fish is cooled from both the outer surface and the inner surface and transferred. The heat area (cooling area) expands. The core temperature measured near the spine of the fish is higher than the temperature of the outer surface of the fish, and cooling from both the outer surface and the inner surface reduces the distance from the portion indicating the core temperature of the fish to the heat transfer surface. Therefore, the effect of lowering the core temperature is increased, and the fish is cooled rapidly.

Sherbet ice is fine ice, preferably having a particle size of 1 mm or less. Sherbet ice can be produced, for example, by giving an impact to supercooled water whose liquid state is maintained even at a temperature below the freezing point by slowly cooling and releasing the supercooled state. Compared to crushed ice, sherbet ice has good fluidity and low temperature holding ability, and has a large contact surface with the outer surface and inner surface of the fish, so that the fish can be cooled more rapidly.

The fish quenching apparatus may further include a flow means for flowing sherbet-like ice in the container. In such a fish quenching device, by flowing sherbet ice on the outer surface of the fish, the heat transfer coefficient is improved as compared with the case where the fish is immersed in ice water by crushing ice, and the fish is cooled rapidly. ..

The flow means is a pipe installed on the wall surface of the container and provided with one or more holes for ejecting sherbet-shaped ice to the fish, and a pump for sending sherbet-shaped ice to the pipe. It may be provided. With such a flow means, sherbet ice can be ejected from a hole provided in the pipe to form a circulating flow of sherbet ice in the container. The pipe may be arranged at a position where sherbet ice flows in the container, and may be arranged on any of the front, rear, and side walls of the fish in the container. The pump may be installed inside the container to circulate the sherbet ice in the container, or may be installed outside the container so that the sherbet ice is supplied from the outside. When the pump is installed outside the container, a circulation path may be provided between the sherbet ice supply source and the container so that the sherbet ice can be sent to the piping inside the container by the pump.

Further, the injection means may include a tube provided with one or more holes inserted into the portion from which the internal organs have been removed and allowing the injected sherbet-like ice to flow out to the portion from which the internal organs have been removed. .. With such an injection means, sherbet ice is injected not only near the opening of the portion from which the internal organs have been removed but also from the position where the hole of the tube is provided. Therefore, the portion from which the internal organs of the fish have been removed is also cooled by the jet of sherbet ice from the hole provided in the tube, and the fish can be cooled more uniformly.

Further, the injection means may further include a pump connected to a tube and injecting sherbet-like ice into the portion from which the internal organs have been removed. With such an injection means, the flow velocity of the sherbet ice ejected from the hole of the tube is increased, and the heat transfer coefficient on the inner surface of the fish is improved, so that the fish can be cooled more rapidly.

The present invention can also be grasped from the aspect of the method. For example, the present invention is a method for quenching fish, which comprises an injection step of injecting sherbet-like ice into a portion of a container filled with sherbet-like ice and from which internal organs of the fish have been removed in a container for holding the fish. You may.

According to the present invention, it is possible to rapidly cool a fish and maintain its freshness.

FIG. 1 is a diagram illustrating the configuration of a fish quenching apparatus. FIG. 2 is a diagram illustrating a container for holding fish. FIG. 3 is a diagram showing an example in which a cross section of tuna is modeled by a one-dimensional cylindrical coordinate system. FIG. 4 is a graph illustrating the temperature distribution inside the tuna every hour in the reference example. FIG. 5 is a graph illustrating the temperature distribution inside the tuna every hour in the embodiment. FIG. 6 is a graph illustrating the change over time in the core temperature of tuna in the reference example. FIG. 7 is a graph illustrating a change over time in the core temperature of tuna in the embodiment. FIG. 8 is a graph showing the cooling effect of the flow of cold seawater inside the tuna. FIG. 9 is a graph illustrating a change over time in the core temperature of tuna according to the intraabdominal flow rate. FIG. 10 is a graph illustrating a change over time in the core temperature of tuna when the heat transfer coefficient of the inner surface of the tuna is reduced to 1/10 in FIG. FIG. 11 is a diagram illustrating the configuration of the fish quenching apparatus in the first modification. FIG. 12 is a diagram illustrating the configuration of the fish quenching apparatus in the second modification.

Hereinafter, embodiments of the present invention will be described. The embodiments shown below exemplify one aspect of the present invention, and do not limit the technical scope of the present invention to the following aspects.

<Composition>
FIG. 1 is a diagram illustrating the configuration of a fish quenching apparatus. The quenching apparatus 1 is an apparatus for rapidly cooling fish, and includes a container 2, a pump 3A, a pump 3B, a tube 4, and a pipe 5. In the embodiment, the fish to be cooled will be described as tuna, but the quenching processing apparatus 1 is not limited to tuna, and can also be used for cooling large-sized fish such as yellowtail, amberjack, bonito, and salmon.

The container 2 is a container for holding the tuna to be cooled. The container 2 is sealed by a lid (not shown), and the temperature rise inside the container 2 due to the outside air is suppressed. The container 2 is not limited to one, and a plurality of tuna may be put into the container 2.

Pump 3A is a pump for pumping sherbet ice into the body of tuna from which internal organs have been removed. A tube 4 provided with one or more holes is connected to the pump 3A, and the tube 4 is inserted into the body through the mouth of the tuna. The pump 3A may be a small axial flow pump, for example, in order to simplify the work of attaching and detaching to and from the tuna. The sherbet ice sent to the tube 4 by the pump 3A forms a jet through the hole of the tube 4 and is sent into the body of the tuna. The gill and anus of the tuna are tightly closed, and the sherbet ice that is sent into the body flows along the inner surface of the tuna from which the internal organs have been removed, and is released from the mouth to the outside of the body. That is, the sherbet ice in the body of the tuna is replaced by the pump 3A, and the inner surface of the tuna can be efficiently cooled.

The tube 4 can have a diameter of, for example, about 20 mm according to the size of the cavity from which the internal organs of the tuna have been removed. In order to prevent deterioration due to salt water, the tube 4 may be made of resin or rubber, and is preferably made of a soft material so that it can be curved according to the shape of the cavity when it is inserted into the body of tuna. The tube 4 may have a tube shape with a closed tip and a plurality of holes so that the sherbet ice can be uniformly supplied into the body of the tuna. The size of the holes and the intervals at which the holes are provided are determined based on the flow rate and flow velocity of sherbet ice, which fluctuates the heat transfer coefficient of the inner surface of the tuna. For example, in order to equalize the flow rate of sherbet ice in the body of the tuna, the size of the holes is made larger or the intervals at which the holes are provided are narrowed at the tip of the tube 4 (the inner part of the body of the tuna). May be good.

The pump 3B is a pump for sending sherbet ice into the pipe 5 to form a jet flow and a circulating flow in the container 2. The pipe 5 has a size that does not affect the capacity of the container 2, and is, for example, a pipe having a diameter of about 20 to 25 mm. Further, the pipe 5 is provided with a plurality of holes on the side surface facing the fish, and the sherbet ice sent to the pipe 5 by the pump 3B forms a jet through the holes of the pipe 5 and is discharged into the container 2. To. In order to prevent deterioration due to salt water, the pipe 5 may be made of a resin such as hard vinyl chloride.

FIG. 2 is a diagram illustrating a container for holding fish. The container 2 includes a lid 2A and a container 2B. The outer walls of the lid 2A and the container 2B are, for example, polyethylene (PE) resin, and hard urethane foam is used as a heat insulating material. The container 2 is sealed by fastening the lid 2A and the container 2B with, for example, a snap lock. The size of the container 2 is preferably about 1700 × 1240 × 775 mm (inner size 1520 × 1040 × 545 mm) in order to hold a large fish.

<Evaluation of cooling effect>
3 to 10 are diagrams for explaining the evaluation result of the cooling effect by the quenching apparatus 1. In order to quantitatively evaluate the cooling effect of the quenching apparatus 1, unsteady heat transfer calculation was performed by modeling a one-dimensional cylindrical coordinate system for tuna with a body diameter of 400 mm (radius Rout = 200 mm). ..

FIG. 3 is a diagram showing an example in which a cross section of tuna is modeled by a one-dimensional cylindrical coordinate system. FIG. 3A is a schematic view of a cross section of tuna. On the right side of the cross section of the tuna, the boundary that distinguishes the parts such as wakare meat, bone grind, lean meat, medium fatty tuna, and large fatty tuna is shown. The tuna spine P1 passes slightly above the center of the tuna cross section, and the temperature near the spine is measured as the core temperature. The core temperature can be measured by a thermometer inserted from the bloodline P2 (artery). The cavity P3 in the body of the tuna is the part where the internal organs have been removed, trimmed and washed.

FIG. 3B shows an example in which the cross section of the tuna shown in FIG. 3A is modeled by a one-dimensional cylindrical coordinate system. The outer surface of the tuna is represented by a circle PM1, and assuming that the body diameter of the tuna is 400 mm, the radius R _out is 200 mm. The cavity P3 in the body of the tuna is represented by a circle PM2, and has a diameter of 140 mm and a radius R _in of 70 mm. Hereinafter, the radius in the tuna cross-section model is simply referred to as R.

In the tuna cross-section model shown in FIG. 3B, the thermophysical property values of tuna shown in Table 1 below are used in the region of 70 mm ≦ R ≦ 200 mm for the radius R. Further, the region of R <70 mm (inside the tuna from which the internal organs have been removed, trimmed and washed) is evaluated using the thermophysical property values of water shown in Table 1.

The basic equation used for the unsteady heat transfer calculation is shown by the following equation (1). As the boundary conditions, it was specified that the radius was R = 0 mm and the axis was symmetrical, and that the boundary of heat transfer was the radius R = 200 mm (R = 70 mm for the sherbet ice portion inside the tuna).

C _p : specific heat, ρ: specific gravity, T: temperature, λ: thermal conductivity, t: time, r: radius

Further, as the difference formula, the following formula (2) was used. Regarding the subscripts, "W" indicates the inner surface of the tuna (west side), "E" indicates the outer surface of the tuna (east side), and "P" indicates the value at the center of the tuna (target axis). "0" indicates that it is a calculated value in the previous calculation when it is calculated at a predetermined time interval Δt.

C _p : Specific heat, ρ: Specific gravity, T: Temperature, λ: Thermal conductivity, t: Time, r: Radius, Δt: Time difference, Δr: Radial difference, h: Heat transfer coefficient

FIG. 4 is a graph illustrating the temperature distribution inside the tuna every hour in the reference example. In the reference example of FIG. 4, the tuna is put into the container 2 filled with crushed ice. Further, heat transfer in the region of R <70 mm is intended only for heat conduction, and natural convection of cold seawater is not considered. In the graph of FIG. 4, the horizontal axis is the coordinates in the radius R direction from the center of the tuna, and the vertical axis is the temperature of the tuna and cold seawater. The heat transfer coefficient between cold seawater and the outer surface of tuna is 20 W / m ²
It is assumed to be K. As an initial condition when the elapsed time from the start of cooling is 0.0 hours, the temperature of cold seawater in the region of R <70 mm is uniform at 3.0 ° C, and the temperature of tuna in the region of 70 mm ≤ R ≤ 200 mm is 28. The temperature of the cold seawater outside the tuna is set to 3.0 ° C.

With the passage of time, the temperature of cold seawater in the region of R <70 mm rises. From the start of cooling to about 4.0 hours later, a temperature distribution in which the temperature rises according to the radius R was formed in a region where the radius R was smaller than about 120 mm. Further, a convex temperature distribution was formed in the region of the tuna portion of 70 mm ≦ R ≦ 200 mm. Approximately 5.0 hours after the start of cooling, the cold seawater in the region of R <70 mm was homogenized to about 17 ° C., and the temperature distribution became lower according to the radius R in the range of 70 mm ≦ R ≦ 200 mm. After about 5.0 hours from the start of cooling, the temperature was lowered as a whole with the passage of time.

FIG. 5 is a graph illustrating the temperature distribution inside the tuna every hour in the embodiment. In the example of FIG. 5, the tuna is cooled by using the quenching apparatus 1 in the present embodiment. In the graph of FIG. 5, the horizontal axis is the coordinates in the radius R direction from the center of the tuna, and the vertical axis is the temperature of the tuna and sherbet ice. The heat transfer coefficient between the sherbet ice and the outer surface of the tuna (R = 200 mm) varies depending on the jet velocity of the sherbet ice, but is assumed to be 200 W / m ² K in FIG. Sherbet ice and tuna inner surface (R = 70mm)
The heat transfer coefficient with and was also assumed to be 200 W / m ² K. The elapsed time from the start of cooling is 0.
As an initial condition when it is 0 hours, the temperature of the sherbet ice in the region of R <70 mm is uniform at −1.5 ° C., the temperature of the tuna in the region of 70 mm ≦ R ≦ 200 mm is uniform at 28 ° C., outside the tuna. The temperature of sherbet ice is -1.5 ° C. With the passage of time, a convex temperature distribution was formed in the region of the tuna portion of 70 mm ≦ R ≦ 200 mm, and with the lapse of time, the temperature was gradually lowered in the range of 70 mm ≦ R ≦ 200 mm. From the graphs shown in FIGS. 4 and 5, it was confirmed that the quenching apparatus 1 can uniformly cool the inner surface of the tuna as compared with the cooling by cold seawater containing crushed ice.

FIG. 6 is a graph illustrating the change over time in the core temperature of tuna in the reference example. In the reference example of FIG. 6, the tuna is put into the container 2 filled with crushed ice, as in the reference example of FIG. Further, heat transfer in the region of R <70 mm is intended only for heat conduction, and natural convection of cold seawater is not considered. In the graph of FIG. 6, the horizontal axis is the elapsed time from the start of cooling, and the vertical axis is the core temperature of the tuna. The heat transfer coefficient between cold seawater and the outer surface of the tuna is assumed to be 20 W / m ² K. The temperature of the tuna in the region of 70 mm ≦ R ≦ 200 mm is assumed to be uniform at 28 ° C. FIG. 6 shows the time course of the core temperature when the temperature of the cold seawater in the region of R <70 mm and the outside of the tuna is −3.0 ° C., −1.5 ° C., 3.0 ° C., and 5.0 ° C. Changes are shown. From about 5 hours after the start of cooling, the cold seawater in the region of R <70 mm is cooler than the inner surface of the tuna and is cooled from both the outside and the inside, so that the tuna is cooled rapidly. However, after about 5 hours, the cooling rate decreased, and the core temperature of the tuna about 10 hours after the start of cooling became about 11 ° C. to 15 ° C. depending on the temperature of the cold seawater at the start of cooling.

FIG. 7 is a graph illustrating a change over time in the core temperature of tuna in the embodiment. In the example of FIG. 7, similarly to the example of FIG. 5, the tuna is cooled by using the quenching apparatus 1 in the present embodiment. In the graph of FIG. 7, the horizontal axis is the elapsed time from the start of cooling, and the vertical axis is the tuna core temperature. It is assumed that the temperature of the tuna in the region of 70 mm ≦ R ≦ 200 mm is uniform at 28 ° C., and the temperature of the cold seawater in the region of R <70 mm and outside the tuna is −1.5 ° C. In FIG. 7, when the heat transfer coefficient between the sherbet ice cream and the outer surface of the tuna (R = 200 mm) is 20 W / m ² K, 200 W / m ² K, 2000 W / m ² K, the tuna core temperature with time is shown. Changes are shown. The heat transfer coefficient between the sherbet ice and the inner surface of the tuna (R = 70 mm) is specified to be the same as the heat transfer coefficient between the sherbet ice and the outer surface of the tuna. The core temperature of tuna decreased with the passage of time. The greater the heat transfer coefficient between the sherbet ice and the outer or inner surface of the tuna (the higher the jet velocity), the faster the tuna is cooled, and the core temperature of the tuna about 10 hours after the start of cooling is 3.0 ° C to − It became about 1.1 ° C. From the graphs shown in FIGS. 6 and 7, according to the quenching apparatus 1, the core temperature of the tuna about 10 hours after the start of cooling is about 8 to 16 ° C. as compared with the cooling with cold seawater containing crushed ice. It was confirmed that the temperature can be lowered. Further, when the cooling effect of the quenching apparatus 1 is compared with the reference example of FIG. 6 under the same conditions that the temperature of sherbet ice and cold seawater is −1.5 ° C. and the heat transfer coefficient is 20 W / m ² K, it is about 1.
It is confirmed that the core temperature of the tuna after 0 hours is lowered by about 8.4 ° C.

FIG. 8 is a graph showing the cooling effect of the flow of cold seawater inside the tuna. In the example of FIG. 8, the tuna is put into the container 2 filled with crushed ice. In FIG. 8, the heat transfer coefficient is 20 W / m ² K when the cold seawater inside the tuna is not flowing (inner water stoppage) and when the cold seawater inside the tuna is flowing (inner flowing water). , 200 W / m ² K, 2000 W / m ² K, the time course of core temperature is shown. The temperature of cold seawater is assumed to be 3.0 ° C. By using the cold seawater inside the tuna as running water, the core temperature of the tuna about 10 hours after the start of cooling could be lowered by about 7 ° C. at each heat transfer coefficient.

9 and 10 show simulation results for estimating the inner surface heat transfer coefficient that can efficiently cool tuna. The inner surface heat transfer coefficient varies depending on the flow velocity of the sherbet ice flowing along the inner surface of the tuna. Therefore, if the desired inner surface heat transfer coefficient is obtained, it is possible to estimate the flow velocity when the sherbet ice is ejected from the holes provided in the tube 4.

FIG. 9 is a graph illustrating a change over time in the core temperature of tuna according to the intraabdominal flow rate. In the graph of FIG. 9, the horizontal axis is the elapsed time from the start of cooling, and the vertical axis is the core temperature of the tuna. As an initial condition, the temperature of the tuna in the region of 70 mm ≦ R ≦ 200 mm is assumed to be uniform at 28 ° C. Further, as other conditions such as the heat transfer coefficient, the following conditions shown in R1 to R7 were specified, and the calculation was performed by the equations (1) and (2).
R1: Ice crushing, ice water temperature = 2 ° C, outer surface heat transfer coefficient = 20 W / m ² K
R2: Sherbet ice (still water), ice water temperature = -1 ° C,
Outer surface heat transfer coefficient = 200 W / m ² K
R3: Sherbet ice (running water), ice water temperature = -1 ° C,
Outer surface heat transfer coefficient = 200 W / m ² K, inner surface heat transfer coefficient = 200 W / m ² K
R4: Sherbet ice (running water), ice water temperature = -1 ° C
Outer surface heat transfer coefficient = 20 W / m ² K, inner surface heat transfer coefficient = 20 W / m ² K
R5: Sherbet ice (running water), ice water temperature = -1 ° C, intraabdominal flow rate 1 L / min
Outer surface heat transfer coefficient = 200 W / m ² K, inner surface heat transfer coefficient = 200 W / m ² K
R6: Sherbet ice (running water), ice water temperature = -1 ° C, intraabdominal flow rate 5 L / min
Outer surface heat transfer coefficient = 200 W / m ² K, inner surface heat transfer coefficient = 200 W / m ² K
R7: Sherbet ice (running water), ice water temperature = -1 ° C, intraabdominal flow rate 10 L / min
Outer surface heat transfer coefficient = 200 W / m ² K, inner surface heat transfer coefficient = 200 W / m ² K

The conditions R1 to R3 differ in whether crushed ice is used as ice water or sherbet ice is used, and whether sherbet ice is allowed to flow in the body of the tuna. The graph corresponding to the condition R3 shows the state of cooling when the sherbet ice is uniformly flowed at -1 ° C in the abdomen of the tuna, and the flow rate in the abdomen for obtaining the same cooling effect as the condition R3. consider. The condition R4 shows the state of cooling when the flow velocity of the sherbet ice is slower than that of the condition R3 and the inner surface heat transfer coefficient is 1/10. From condition R5 to condition R7, the heat transfer coefficient of the inner surface is set to 200 W / m ² K as in condition R3, and the state of cooling when the condition of the intra-abdominal flow rate of tuna is changed is shown.

From the graphs corresponding to the conditions R5 to R7, it can be seen that when the flow rate in the abdomen is small, the temperature in the abdomen rises and the cooling effect decreases. Further, in order to obtain the same cooling effect as the condition R3, it is desirable that the intraabdominal flow rate is 5 L / min (condition R6) or more.

FIG. 10 is a graph illustrating a change over time in the core temperature of tuna when the heat transfer coefficient of the inner surface of the tuna is reduced to 1/10 in FIG. In the graph of FIG. 10, the horizontal axis is the elapsed time from the start of cooling, and the vertical axis is the tuna core temperature. As an initial condition, the temperature of the tuna in the region of 70 mm ≦ R ≦ 200 mm is assumed to be uniform at 28 ° C. The graph of condition R1 to condition R4 is the same as that of FIG. In FIG. 10, a graph based on the calculation results under the following conditions R51 to R71 in which the inner surface transmissivity is set to 1/10 under the conditions R5 to R7 of FIG. 9 is shown.
R51: Sherbet ice (running water), ice water temperature = -1 ° C, intraabdominal flow rate 1 L / min
Outer surface heat transfer coefficient = 200 W / m ² K, inner surface heat transfer coefficient = 20 W / m ² K
R61: Sherbet ice (running water), ice water temperature = -1 ° C, intraabdominal flow rate 5 L / min
Outer surface heat transfer coefficient = 200 W / m ² K, inner surface heat transfer coefficient = 20 W / m ² K
R71: Sherbet ice (running water), ice water temperature = -1 ° C, intraabdominal flow rate 10 L / min
Outer surface heat transfer coefficient = 200 W / m ² K, inner surface heat transfer coefficient = 20 W / m ² K

When calculated under the conditions R61 and the condition R71 where the intraabdominal flow rate is 5 L / min or more, it can be seen that the core temperature of the tuna is about 1 ° C. higher than the graph of the condition R3 600 minutes after the start of cooling. In addition, 900 minutes after the start of cooling, the core temperature of the tuna is lowered to the same level as in the case of FIG.

In order to obtain the same cooling effect as in the case of the condition R3, it is desirable that the inner surface heat transfer coefficient is 200 W / m ² K or more, as can be seen from the graphs of the condition R6 and the condition R7 in FIG.
Here, assuming that the heat transfer coefficient of the flow along the flat plate is h, the total length of the tuna is L = 1 m, and the thermal conductivity of water is λ = 0.55 w / mK, the heat transfer due to convection between the fluid and the object in contact with the fluid The Nusselt number Nu representing the magnitude is represented by Nu = h · L / λ. Further, assuming that the thermal diffusivity of water is α = 1.31 × 10-7 [m ² / s] and the kinematic viscosity coefficient of water is ν = 1.79 × 10-6 [m ² / s], the number of water plants is increased. It is expressed as Pr = ν / α. Further, the Reynolds number Re _L , which characterizes the behavior of the viscous fluid, is Re _L = u · L / ν = 72626 [−] when the flow velocity of the sherbet ice is u = 0.13 m / s. In this case, from the Nusselt number Nu = h · L / λ = 0.644 · Pr ^1/3 · Re _L ^1/2 = 415 [-], the heat transfer coefficient is h = 41.
5. λ / L = 228 [W / m ² K]. Therefore, in order to obtain an inner surface heat transfer coefficient of 200 W / m ² K or more, it is desirable that the flow velocity of the sherbet ice is 0.13 m / s or more.

<Action and effect of the embodiment>
The quenching apparatus 1 of the present embodiment can improve the heat transfer coefficient by flowing sherbet ice on the outer surface of the tuna, and can rapidly cool the tuna. In addition, by injecting sherbet ice into the part where the internal organs of the tuna have been removed, the tuna is cooled from both the outer surface and the inner surface, the heat transfer area is expanded, and the part showing the core temperature of the tuna The distance to the heat transfer surface decreases. Therefore, the effect of lowering the core temperature is increased, and the tuna is cooled rapidly. In addition, sherbet ice has better fluidity and low temperature holding ability than crushed ice, and has a large contact surface with the inner and outer surfaces of tuna, so that tuna can be cooled more rapidly.

Further, the quenching apparatus 1 can form a circulating flow of sherbet ice in the container 2 by sending the sherbet ice to the pipe 5 by the pump 3B and ejecting the sherbet ice from the holes provided in the pipe 5. ..

The inner surface of the tuna is formed by inserting a tube 4 having a hole for allowing the sherbet ice to flow out into the portion where the internal organs of the tuna have been removed, and injecting the sherbet ice into the body of the tuna through the hole of the tube 4. Is cooled more evenly. Further, by feeding the sherbet ice into the tube 4 by the pump 3A, the flow velocity of the sherbet ice ejected from the hole of the tube 4 becomes high, and the heat transfer coefficient on the inner surface of the tuna is improved. Therefore, the tuna is also efficiently cooled from the inner surface, and the tuna can be cooled more rapidly.

<Modification example>
In the above embodiment, a small axial flow pump is adopted in order to simplify the work of attaching and detaching the pump 3A and the tube 4 for flowing the sherbet ice into the body of the tuna. The means for flowing sherbet ice into the body of tuna is not limited to the example of the above embodiment. 11 and 12 show a modification 1 and a modification 2 of the fish quenching apparatus 1, respectively.

FIG. 11 is a diagram illustrating the configuration of the fish quenching apparatus in the first modification. The fish quenching apparatus 1A in the first modification includes a pump 3C and a tube pipe 4A instead of the pump 3A. The pump 3C is a pump for sending sherbet ice to the tube 4 inserted into the body of the tuna via the tube pipe 4A. The tube pipe 4A connects the pump 3C and the tube 4. The tube pipe 4A may be connected to the pipe 5 and the sherbet ice may be sent to the tube 4 by the pump 3B.

FIG. 12 is a diagram illustrating the configuration of the fish quenching apparatus in the second modification. The fish quenching apparatus 1B in the second modification includes a trumpet-shaped insertion port 4B connected to the tube 4 instead of the pump 3A. The insertion port 4B has a shape that spreads like a trumpet from the connection portion with the tube 4 toward the inside of the container 2, for example. The sherbet ice ejected from the pipe 5 flows into the tube 4 through the opening of the insertion port 4B due to the dynamic pressure of the jet stream. The insertion port 4B may be provided with a fixing member for preventing the tuna from coming off the mouth.

Also in the above modification, the sherbet ice flows in the body of the tuna, and the tuna is cooled from both the outer surface and the inner surface, so that the cooling effect is improved and the tuna can be rapidly cooled. In the above-described embodiment and modified example, an example in which sherbet ice is allowed to flow in the body of tuna is shown, but it is also possible to rapidly cool the tuna and maintain its freshness by flowing crushed ice in the body of tuna. is there.

1 ・ ・ Quenching equipment: 2 ・ ・ Container: 3A, 3B, 3C ・ ・ Pump: 4 ・ ・ Tube: 5 ・ ・ Piping

Claims (10)

A container filled with sherbet-like ice to hold fish,
An injection means for injecting the sherbet-like ice into a portion of the container from which the internal organs of the fish have been removed is provided.
The injection means has one or more holes and has a tube that is inserted into the body through the mouth of the fish and feeds the sherbet-like ice into the body.
Quenching equipment for fish. Further provided with a flow means for flowing the sherbet-like ice in the container.
The fish quenching processing apparatus according to claim 1. The flow means
A pipe installed on a wall surface in the container and provided with one or more holes for ejecting the sherbet-like ice to the fish.
A pump for feeding the sherbet-like ice into the pipe.
The fish quenching processing apparatus according to claim 2. The hole in which the tube has, the viscera are inserted to the removed portion, Ru and injected the sherbet-like ice is flowing out to the portion where the internal organs have been removed,
The fish quenching apparatus according to any one of claims 1 to 3. The injection means further comprises a second pump connected to the tube and injecting the sherbet-like ice into the portion from which the internal organs have been removed.
The fish quenching apparatus according to any one of claims 1 to 4. A third pump for flowing the sherbet-like ice in the container is further provided.
The tube is inserted into the portion from which the internal organs have been removed, and the injected sherbet-like ice is allowed to flow out to the portion from which the internal organs have been removed.
The injection means further comprises a fourth pump connected to the tube and injecting the sherbet-like ice into the portion from which the internal organs have been removed.
The fish quenching processing apparatus according to claim 1. Further provided with a flow means for flowing the sherbet-like ice in the container,
The flow means includes a fifth pump that sends the sherbet-like ice that flows in the container in the length direction of the fish.
The sherbet-like ice pumped into the container by the fifth pump flows in a direction along the surface of the fish.
The fish quenching processing apparatus according to claim 1. It has an injection step of injecting sherbet-like ice into a portion of the fish from which the internal organs have been removed in a container filled with sherbet-like ice and holding the fish.
The injection step is
An insertion step in which a tube having one or more holes is inserted into the body through the mouth of the fish,
The insertion step includes a step of feeding the sherbet-like ice into the body through the tube inserted into the body.
How to quench fish. It has an injection step of injecting sherbet-like ice into a portion of the fish from which the internal organs have been removed in a container filled with sherbet-like ice and holding the fish.
The injection step is
An insertion step in which a tube having one or more holes is inserted into the body through the mouth of the fish,
The insertion step includes a step of feeding the sherbet-like ice into the body through the tube inserted into the body.
How to cool the fish. It has an injection step of injecting sherbet-like ice into a portion of the fish from which the internal organs have been removed in a container filled with sherbet-like ice and holding the fish.
The injection step is
An insertion step in which a tube having one or more holes is inserted into the body through the mouth of the fish,
The insertion step includes a step of feeding the sherbet-like ice into the body through the tube inserted into the body.
How to make a cooled fish.