JPH10165039A - Method for preserving live fish and transporting method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for preserving a live fish at a low temperature for a long time and efficiently transporting the live fish. SOLUTION: The fish is left in the eugenol solution of prescribed concentration (A), the fish is iced by rapidly cooling the eugenol solution almost to 0 deg.C (D) at a motion stop time point (B) of fish and when the fish is left in clear water (F) after it is iced for fixed time (D-E), the fish starts usual swimming (G). Processing from leaving (A) to fish icing (D) is performed before transportation, the fish is transported during icing for fixed time (D-E) and when arriving at the destination, the fish is left in clear water (F).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for storing and transporting live fish, and more particularly to storing live fish at a low temperature for a long time.
Also, the present invention relates to a method of transporting at low temperature.

[0002]

2. Description of the Related Art Conventionally, as a method of transporting marine products, particularly transport of fish and shellfish, low-temperature transport, frozen transport, and live fish transport have been mainly used. Low-temperature transportation includes low-temperature fresh fish transportation and normal low-temperature transportation, and the former low-temperature fresh fish transportation is a method of transporting fresh fish in a hibernating state, and is mainly used for hibernating fish (horse mackerel, Thailand, puffer fish, etc.). . The latter is a method of immediately killing, packing together with finely crushed ice and transporting it as fresh fish, and is used for transporting hamachi, rainbow trout and the like. The frozen transportation removes the gills and built-in fish that have been transported at low temperature, puts them in plastic bags one by one, and puts them in a paper case for each specified weight, and freezes them by rapid freezing (-40 ° C, 1 hour). It is transported as it is, and is applied to rainbow trout for transportation and the like. In addition, live fish transport is a method of releasing 4 to 5% by weight of fish into a cage placed on a truck or the like and transporting live fish, and is applied to transport of eels and carps. In addition, in the case of shellfish and prawns that can survive for a short time even after being picked up from the water, arrange them in three layers in refrigerated sawdust and transport them as they are with ice bags etc. on top. In some cases, waterless transport takes place.

[0003] In addition, a method of storing marine products at a low temperature generally includes a cooling storage method of lowering the temperature of the marine products to a temperature at which water in the marine products starts to freeze (freezing point) and maintaining the state, Temperature at which water freezes (eutectic point -60
° C) or higher (-18 ° C or lower).

[0004] There are two cooling storage methods: ice cooling (cooling with ice), which lowers the temperature to near 0 ° C with ice, and ice storage, in which the product temperature is held and stored by ice.

[0005]

Among the above-mentioned transportation methods, live fish transportation, in particular, can transport fish alive. Therefore, the method of transporting fish to be used in restaurants and the like, or subsequent aquaculture. It is widely used as a method of transporting fry.

[0006] However, the method of transporting live fish is mainly a method of transporting through a live cage, and in reality, the weight ratio is 4 to 5 in terms of weight.
% Of fish are transported, and there is a problem that transportation efficiency is extremely poor. In particular, cephalopods such as squid and octopus have extremely poor transport efficiency. In addition, since it is transported alive, water management during transportation is necessary in consideration of the consumption of oxygen by metabolism, the production of excretions, particularly the generation of harmful ammonia, and the cost is increased. In addition, the body surface of the fish is easily damaged by the vibration of the water caused by the vibration of trucks and the like, and the stress may occur during the transportation and the survival rate after the transportation may be reduced, which may be economically disadvantageous. There were many.

In recent years, a technique has been developed in which live fish that are mainly hibernating are transported and stored during hibernation. However, when transporting by hibernation preservation,
First, it takes time to bring the live fish into hibernation in preparation for transportation, and second, it is difficult to apply the method to those that do not hibernate. In particular, the first point is that the live fish need to be cooled slowly over a long period of time, so that the preservation restraint time for the live fish is long and the stress is exerted. There is a disadvantage that a long time is required.

The present invention has been made in view of the above-mentioned problems, and proposes a method capable of storing living fish at a low temperature for a long time, thereby further reducing the preparation time. The present invention proposes a transportation method that enables economical live fish transportation and can reduce stress on fish as much as possible.

[0009]

According to the present invention, a live fish is brought into a state of asphyxia with eugenol, and then rapidly cooled to a level of 0%.
氷 ° C or lower and within a temperature range not exceeding a temperature at which the cell membrane of the fish is destroyed for a predetermined time, and thereafter,
This is a method for storing a live fish having a configuration in which the fish is released into water having a swimming temperature of the fish.

Furthermore, the present invention relates to a method for producing a live fish in a state of asphyxia by eugenol prior to transportation, and then quenching the live fish to a temperature of 0 ° C. or less and a temperature not exceeding the temperature at which the cell membrane of the fish is destroyed. And transporting the fish in ice in that state, and after reaching the destination, releasing the fish into water having a swimming temperature of the fish.

As described above, according to the present invention, fish can be stored at a low temperature in a suspended state, and after a certain period of time, the fish can be revived in water at room temperature without affecting the living body of the fish. is there. Therefore, it becomes possible to transport fish in ice storage,
It is possible to efficiently and economically transport live fish in a compact transport state without performing water management or the like for that purpose.

Further, according to the present invention, the time required for storing the live fish on ice can be extremely shortened as compared with the conventional case of hibernation of the live fish, so that the preparation time for transporting the fish can be shortened. As a result, the total time required for transportation can be reduced, and the stress on the fish can be reduced as much as possible.

Further, when fish are transported using the present invention, stress is not applied to the fish during transportation as in the prior art, so that the freshness of the fish is maintained, and the survival rate and the survival state after transportation are extremely excellent. Can be performed.

The term "ice storage" literally means that a low temperature is maintained by using ice or a refrigeration system or an appropriate means in addition to maintaining a low temperature with ice. The meaning of rapid cooling includes rapid freezing, but does not include slow cooling as used in hibernation and dormancy.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on specific examples.

First, fresh water was flowed into a water tank, and an eugenol solution was dropped therein. In this example, 0.2 ml of a 10% by weight eugenol solution was added to 1 L of tap water to obtain a 2.0 × 10 ^-5 % by weight (20 ppm) eugenol solution, and a water tank filled with the eugenol solution (Hereinafter, eugenol solution tank), the following experiment was performed.

FIG. 1 is a diagram showing the chemical structural formula of the substance used in the method of the present invention. The eugenol (eug) shown in FIG.
enol: 4-Allyl-2-methyoxyphe
Nol) is a component of spices generally used for ham, ice cream and the like, and is a colorless or light yellow-brown transparent liquid extracted from the t-shape of a plant, and has a spicy scent of spicy aroma. Eugenol is used as a raw material for producing vanillin, a preservative, an anesthetic for fish and crustaceans, and the like. Since eugenol is hardly soluble in water, it was dissolved in alcohol and further diluted with water to obtain a 10% by weight eugenol solution.

In this example, the test object was Peheley (scientific name: odontesthesbonariensi).
s, English name; Atlantic Silverside) was subjected to the test. Pehelay is a freshwater saltwater fish of the family Anchovy, mainly originating from the La Plata River in Argentina, and is a delicious white fish with a similar taste to kisses and sayori. Under normal conditions, Peheley cannot survive if its body temperature is below 8 ° C.

The test was conducted by arbitrarily selecting Peheley, which was cultivated by Kaneko Fishery Co., Ltd. in Saitama Prefecture.

The test was performed in the following procedure.

First, Peheley having an average weight of 200 g to 300 g and a body length of 30 cm to 35 cm was arbitrarily placed in a culture tank at 5 cm.
The animals were selected and released into the eugenol solution tank.

FIG. 2 is a diagram showing the situation (time) after discharge into the eugenol solution, the Pegley environment state discharged into the eugenol solution, and the temperature change of the Pegley environment state subsequently discharged into fresh water.

As shown in FIG. 2, since the test was carried out at room temperature, the initial solution temperature of the eugenol solution tank was:
It was around 22 ° C. (point A in FIG. 2).

After being discharged into the eugenol solution tank, Pehelei stopped moving in about 3 to 5 minutes and turned around (point B in FIG. 2). At this time, piercing Peheley with a pin, if it does not move, admitting that it is in a state of temporary asphyxia
It moved to the later stage. It should be noted that the time varies depending on the individual differences between the five animals, and the first one stops moving for three minutes, and the last one for five minutes. In the following:
Variations in time are for similar reasons.

Thereafter, a large amount of ice was put into the eugenol solution tank to rapidly lower the water temperature, and the movement of the gills was stopped (point C in FIG. 2). After palpation, the heart of Pehelei almost stopped moving (point C). At point (D in FIG. 2), it was recognized that Peheley was in a complete asphyxia state. After Peheley was completely suspended, the eugenol solution tank was further cooled on ice to maintain a low temperature.

In this case, it is considered that the shorter the time until the ice-cooling is, the shorter the time is, from the viewpoint of maintaining the freshness of the fish, and the effect of eugenol, which maintains the state of asphyxia by the ice-cold cold stimulation. . The time required from the release of Peheley into the eugenol solution water tank until the ice-cooling state is reached is about 9 to 14 minutes (points A to D in FIG. 2). Further, the water temperature of the eugenol solution tank at the time point when Pehelei was completely put into a temporary asphyxia state (point D in FIG. 2) was 0 ° C.
Before and after.

Then, the temperature was kept at 0 ° C. or lower, and the Peheley was refrigerated for 3 hours (point D-E in FIG. 2). The ice storage temperature may be adjusted from 0 ° C. or lower to a temperature slightly higher than a temperature (freezing point) at which water in the marine product starts to freeze (freezing point). As the temperature becomes lower than 0 ° C., the freshness retention period is extended, but if the temperature is too low, the fish cells freeze and cause cell destruction. Therefore, it is preferable to store the fish at the lowest temperature that does not cause cell destruction. The freezing point differs depending on the target marine product. For example, the freezing point of a freshwater fish is -0.5 ° C, the freezing point of a semi-watered fish is -0.75 ° C, and the freezing point of a saltwater fish is -1.5 ° C.
° C.

When an antifreeze protein (antifreeze protein), that is, a protein having an effect of lowering the coagulation temperature of a biological fluid, is used together with eugenol, the freezing point is considered to be further lowered, and thus the freshness is further improved. It is assumed that ice can be stored in good condition.

The temperature of the ice storage can be delicately adjusted by adding a salt to the solution for ice storage. For example, normal ice (fresh water ice) melts at 0 ° C., and ice obtained by freezing seawater melts at −2 ° C.
That is, the temperature does not reach 0 ° C. for fresh water ice and −2 ° C. or less for seawater ice. For this reason, when storing fish in ice, if the salt of the appropriate concentration is added, the ice cooling temperature can be changed slightly, and the temperature of the ice storage below 0 ° C and above the freezing point can be finely adjusted. Becomes For example, in the case where ice is stored by adding a salt slightly lower than the salt concentration of the body fluid of the fish, the ice storage temperature is slightly higher than the freezing point of the fish, so that the ice can be stored without destruction of the cells of the fish. . The salt concentration at this time varies depending on the fish species, but is specifically 0.
It is considered appropriate to add a salt (such as NaCl) at a concentration of ０．９0.9% by weight. In this way, when the ice storage temperature is adjusted by adding an appropriate concentration of salt, the fish is ice-stored at the optimum temperature,
Further, since there is no need to finely adjust the outside air temperature in the ice storage state, the temperature management is facilitated, and there is an advantage of reducing costs.

After 3 hours (point E in FIG. 2), the ice-stored Pehelei was taken out of the eugenol solution water tank and discharged into a fresh water (normal water) water tank (point F in FIG. 2).

In this water tank, a water flow is artificially formed in order to supply a large amount of oxygen to Pehelay. In addition, the water tank is left at room temperature of about 20 ° C. ° C. Pehelei, which was released into clear water, started swimming that appeared normal after 3 to 10 minutes (point G in FIG. 2).

It was confirmed that Pehelei also exhibited a spice odor during ice storage due to the spice odor of eugenol, but this spice odor disappeared when released into fresh water after ice storage. It is considered that this is because eugenol is digested from inside the body of Peheley by respiration and the like and excreted from gills and the like.

In this experiment, five individuals were used in one test, and the test was repeated three times using different individuals. In this experiment, 15 individuals were frozen in ice for a certain period of time in a suspended state, and then released into clear water, all individuals started swimming, which appeared to be normal. Has reached.

Next, a separately performed test is disclosed.

(Comparative Example 1) As an object test, five individuals selected arbitrarily from a farm similar to the above-mentioned test were
It is discharged into clear water (non-eugenol solution tank) at around 20 ° C, and after about 2 to 3 minutes after being discharged into clear water, the clear water is gradually cooled with ice and about 10 minutes have passed since the fish was released into clear water. At that time, a test was conducted in which the fresh water was rapidly cooled with ice to an ice storage state of 0 ° C. to 2 ° C., and after keeping the ice storage state for 3 hours, the fish in the ice storage state was released into fresh water at about 20 ° C. . In this case, all five individuals did not survive and all died.

In this example, only the non-eugenol solution tank is different from the successful example. Therefore, in the practice of the present invention, it is necessary to bring about asphyxia with eugenol.

(Comparative Example 2): As an object test, five individuals arbitrarily selected from the same farm as the above-mentioned test were
Discharged to an eugenol solution water tank at about 20 ° C., and about 10 minutes after the discharge to the eugenol solution water tank, in a state where Pehelei does not become a complete asphyxia state,
A test was conducted in which the eugenol solution water tank was rapidly cooled with ice to an ice storage state of 0 ° C. or less, the ice storage state was maintained for 3 hours, and then the fish in the ice storage state was released into clear water at about 20 ° C. Again, all five individuals died without surviving.

In the case of this example, before the child does not enter the suspended state,
It is probable that because of the rapid ice-cooling of Pehelei, the fish's respiratory function declined while oxidative metabolism was still taking place in the body of the fish, and oxygen was no longer supplied, and the fish died in a state of lack of oxygen.

(Comparative Example 3): As an object test, five individuals arbitrarily selected from the same farm as the above-mentioned test were
After being discharged into the eugenol solution water tank at about 20 ° C., and about 12 minutes after the release into the eugenol solution water tank, it was confirmed that Pehelei was in a completely suspended state, and then the eugenol solution water tank was rapidly cooled with ice. 0 ° C to 2 ° C
The ice storage state, that is, 0 ° C. to 2 ° C.
After keeping for a time, a test was conducted in which the fish in the frozen state were released into fresh water at about 20 ° C. Again, all five individuals died without surviving.

As in the case of this example, the temperature is 10 ° C. or higher than the freezing temperature.
If the fish is kept in the following aquarium for a long time, the fish will remain in a state of asphyxia with respiration stopped, but enzymes will work in the body and metabolism will be started, resulting in a lack of oxygen. The fish are considered dead.

When the above Comparative Examples 1 to 3 are compared with the above-mentioned successful examples (this experiment), the following points can be considered.

That is, in the case of this experiment, Pegley was discharged into the eugenol solution, and ice-cooling was rapidly started from a state in which the movement stopped, and then ice-cooling was performed for a certain period of time. The synergistic effect of the cold stimulus maintains the fish's asphyxia. Therefore, fish
It is considered that ice is stored while biological metabolism such as P synthesis is extremely slow. Therefore, the amount of oxygen consumed by metabolism is extremely small, and it is considered that the oxygen remaining in the body is sufficient for the metabolism of the fish in the state of asphyxia.

Normally, ATP is maintained at a constant level by the action of an enzyme even after fish stop breathing. However, in this experiment, the enzyme activity was suppressed by ice-cooling ice storage after stopping breathing to suppress the enzyme activity. It is considered that they maintain a certain level of ATP. After that, the fish is released into fresh water with a large supply of oxygen at 20 ° C to 23 ° C, and oxygen is actively supplied to the fish before the movement of the gills becomes normal. Is started, and it is considered that the child is revived from the suspended state.

For this reason, it is preferable that after the fish are stored on ice, it is immediately discharged into a water tank at a normal temperature (about 20 ° C.) where a large amount of oxygen is supplied. It is also conceivable to use a special aquarium suitable for supplying a large amount of oxygen to fish after ice storage.

In this experiment, the experiment was carried out using Peheley. However, it is assumed that the method of this example can be applied to other fish, crustaceans and cephalopods by adjusting the eugenol solution concentration. You. In addition, body length 30cm-35c
The fish can be put into a suspended state simply by releasing a relatively large fish into the eugenol solution, so that the fish can be put into a suspended state easily without the need for complicated work such as injecting one fish at a time. It is thought that it can be.

It is also assumed that effects similar to those of the present example can be obtained by using a substance having a structure similar to eugenol other than eugenol.

As described above, when the live fish are released into the eugenol solution to be put into a suspended state, the fish in the suspended state are kept in an ice storage state for a certain period of time, and after the ice storage, the fish is released into fresh water, and the normal survival state of the fish is observed. It was confirmed that the fish could be kept alive for a certain period of time in an icy condition, so that the fish could be transported in an icy condition.

That is, prior to transportation, the live fish are discharged into the eugenol solution by the above-described method to make the fish in a suspended state, and the fish in the suspended state are placed in an ice storage state. Then, the fish in the ice storage state are stored in a container or the like, transported, and after arriving at the destination, the fish in the ice storage state are released from the container into clear water such as a cage, and the fish in the suspended state are restored. Start swimming.

According to the transportation method of this embodiment described above, live fish can be transported efficiently and economically in a compact transportation state without using a living pens and water management for the same as in the prior art. It becomes possible. In addition, when fish and the like are transported using this method, stress is not generated in the fish and the like during transportation, so that the fish and the like can be transported with freshness, and the survival rate and the survival state after transportation are extremely good. Transport becomes possible.

[0050]

As described above, according to the present invention, a live fish is brought into a state of asphyxia by eugenol and then rapidly cooled to a temperature of 0 ° C. or less and a temperature not exceeding the temperature at which the cell membrane of the fish is destroyed. Refrigerate for a predetermined time within the range,
Thereafter, a method for storing live fish configured to release the fish into water having a swimming temperature of the fish, and before transport,
After bringing the live fish into a state of asphyxia with eugenol,
After quenching, it was placed in a temperature range of 0 ° C. or less and a temperature not exceeding the temperature at which the cell membrane of the fish was destroyed, transported in that state with ice storage, and provided with the swimming temperature of the fish after reaching the destination. This is a method for transporting live fish configured to discharge the fish into water.

As described above, according to the present invention, fish can be stored at a low temperature in a suspended state, and after a certain period of time, the fish can be revived in water at room temperature without affecting the living body of the fish. is there. Therefore, it becomes possible to transport fish in ice storage,
It is possible to efficiently and economically transport live fish in a compact transport state without performing water management or the like for that purpose.

Further, according to the present invention, the time required for storing the live fish on ice can be significantly reduced as compared with the conventional case of hibernation of the live fish, so that the preparation time for transporting the fish can be shortened. As a result, the total time required for transportation can be reduced, and the stress on the fish can be reduced as much as possible.

Furthermore, when fish are transported using the present invention, stress is not applied to the fish during transportation as in the prior art, so that the freshness of the fish is maintained, and the survival rate and the survival state after transportation are extremely excellent. Can be performed.

[Brief description of the drawings]

FIG. 1 is a diagram showing the structural formula of eugenol used in the present invention.

FIG. 2 is a diagram showing the relationship between the temperature of eugenol solution, water temperature in ice water and fresh water after ice storage and time, and the state of fish according to the present invention.

[Explanation of symbols]

 A point at which fish is released into eugenol solution B point at which fish stops moving C point at which fish gills stop moving D point at which the heart of the fish stops (ice storage starts) E end of ice storage F point at which fish is released into clear water G normal swimming of fish Start time

Claims (4)

[Claims] 1. The method according to claim 1, wherein the live fish is eugenol.
l: 4-Allyl-2-methypheno
After being brought into a suspended state according to 1), the mixture was rapidly cooled, and ice-cooled for a predetermined time within a range of 0 ° C. or less and a temperature not exceeding a temperature at which the cell membrane of the fish was destroyed, and then provided with a swimming temperature of the fish. A method for preserving live fish, comprising releasing the fish into water. 2. The live fish is Peheley (scientific name: odont).
2. The method for preserving live fish according to claim 1, wherein the live fish is an esthes bonariensis. 3. The method according to claim 1, wherein the fish is released into flowing water after the ice storage. 4. Prior to transportation, the live fish are brought into a state of asphyxia by eugenol, then quenched and placed in a temperature range of 0 ° C. or less and a temperature not exceeding the temperature at which the cell membrane of the fish is destroyed. A method of transporting live fish, wherein the fish is transported in ice in a state, and after reaching the destination, the fish is released into water having a swimming temperature of the fish.