JP4393254B2 - Bivalve purification method, bivalve purification determination method, and bivalve purification device - Google Patents

Description

  The present invention relates to a method for purifying a bivalve by discharging or killing norovirus incorporated in a bivalve such as oysters, a determination method for purification by this method, and a purification apparatus for carrying out this purification method. In particular, the present invention relates to a measure for making it possible to significantly reduce the infectivity of norovirus in a short time.

  Conventionally, sodium hypochlorite, ultraviolet rays, ozone, and the like have been used as methods for cleaning and sterilizing live fish and shellfish. In a method using sodium hypochlorite (see, for example, Patent Document 1 below), there is a problem that a sufficient bactericidal effect cannot be obtained even if treatment is performed with a high concentration solution having a free residual chlorine concentration of 10 to 20 ppm. . In the method using ultraviolet rays (for example, see Patent Document 2 below), the effect is small unless it is a shallow water tank, and a sufficient effect cannot be obtained if light is blocked by suspended particles in water. A method using ozone (see, for example, Patent Document 3 below) has a high bactericidal effect, but is highly toxic to humans of residual oxidants and is difficult to use because it causes corrosion of metallic tanks and piping.

  By the way, in September 1993, the Ministry of Health and Welfare (current Ministry of Health, Labor and Welfare) designated the calicivirus norovirus as a food poisoning agent. This norovirus is the main causative agent in viral food poisoning of oysters. In other words, norovirus accumulated in the midgut gland of oysters enters the body of a person who eats oysters without heat treatment, and then grows in mucosal cells such as intestines. Gastrointestinal inflammation symptoms such as are induced. In fact, when no fungi are detected in the vomit of a person complaining of food poisoning, this norovirus is often detected.

In order to prevent viral food poisoning due to this norovirus, it is recalled that a substance that inhibits virus growth or a substance that kills the virus may be used in order to reduce the number of viruses in food. In order to find this substance, it is necessary to first establish a culture technique for norovirus. However, since this norovirus grows only in human intestinal cells, it is difficult to realize its culture environment, Not established. For this reason, it is extremely difficult to examine what substances have the ability to kill viruses against Norovirus.
JP-A-9-308886 Japanese Patent Laid-Open No. 10-249364 JP 2000-106856 A

  Although it is possible to kill Norovirus to a certain extent by the above-mentioned sterilization methods (methods using sodium hypochlorite, ultraviolet rays, ozone), the number of viruses is still high enough to not cause food poisoning. The effect of reliably reducing it is not obtained.

  Specifically, food poisoning caused by norovirus is said to develop when a person ingests about 100 noroviruses. The average number of noroviruses per oyster incorporating norovirus is several thousand (for example, 5,000). Assuming that the number of raw oysters a person eats at a maximum is eight, in order to reliably avoid the onset, the number of norovirus per oyster is reduced to about 1/1000 (total intake) It is necessary to reduce the number of viruses to about 40 to ensure that the onset can be avoided). When trying to kill noroviruses using conventional sterilization methods, it is difficult to reduce the number of noroviruses to about 1/1000, and the reliability is not obtained.

  Thus, the technique regarding the eradication virus about norovirus which is the main causative substance in the viral food poisoning of oysters is not yet established.

  The present invention has been made in view of such points, and the object of the present invention is to allow bivalves, particularly norovirus, which is a main causative substance in viral food poisoning of oysters, to be effectively ejected from bivalves in a short time. It is another object of the present invention to provide a bivalve purification method, a determination method for purification by this method, and a bivalve purification device that can be killed to significantly reduce the infectivity of norovirus.

-Summary of invention-
The solution of the present invention, which has been devised in order to achieve the above-mentioned object, excretes or kills norovirus by effectively utilizing the bivalve physiological activity (exercise for taking up plankton and oxygen). That is, since the water constantly passes through the bivalve by this physiological activity, the norovirus in the shell is discharged outside the shell by this water flow, and the discharged norovirus is killed by the electrolyzed water. In addition, temperature-controlled warm water is passed through the bivalves, so that norovirus is always exposed to high temperatures and killed.

-Solution-
Specifically, the present invention is premised on a method for purifying a bivalve by discharging norovirus incorporated into the bivalve from the bivalve. In contrast to this bivalve purification method, bivalve shells are placed in a septic tank containing purified water, and the electrolyzed water is temperature-controlled so that the bivalve is physiologically active. At the same time, electrolyzed water is allowed to pass through the bivalves, the norovirus in the shells is discharged out of the shell together with the water flow, and the norovirus is killed by the electrolyzed water. In this case, the temperature of the purified water composed of electrolyzed water is controlled within a range of 10 to 43 ° C.

  Due to this specific matter, the bivalve put in the septic tank takes in the electrolyzed water in the septic tank into the shell and discharges the electrolyzed water in the shell due to its physiological activity. That is, cilia movement is performed to filter out plankton in the water and absorb oxygen. As a result, the electrolyzed water passes through the inside of the bivalve shell, and with this passage, the norovirus in the shell is discharged out of the shell together with the water flow, and the purification in the shell is performed. In addition, the discharged norovirus is always in contact with the electrolyzed water and is killed by the action of the electrolyzed water. For this reason, the number of noroviruses present in the electrolyzed water taken into the shell is also reduced, and the infectivity value of norovirus can be greatly reduced. Also, electrolyzed water comes into contact with norovirus that remains in the shellfish and can be killed. The reason for managing the electrolyzed water at the above temperature is that when the temperature of the purified water is less than 10 ° C., the physiological activity of the bivalves is not performed and norovirus cannot be discharged, and the temperature of the purified water is 43 ° C. This is because heat denaturation occurs in the bivalve protein and the bioactivity becomes impossible.

  Moreover, the purification apparatus for implementing this bivalve purification method is also within the scope of the technical idea of the present invention. That is, a septic tank storing purified water, electrolyzing means for generating electrolyzed water by electrolyzing the purified water, and temperature adjusting means for adjusting the temperature of the electrolyzed water to a temperature at which bivalves are physiologically active. It is the purification apparatus provided with.

  Moreover, the following are mentioned as another solution means concerning the purification method of a bivalve. That is, a method for purifying the bivalve by killing the norovirus incorporated in the bivalve is assumed. For this bivalve purification method, the bivalve is put in the bivalve by putting the bivalve in the septic tank storing the purified water and controlling the temperature as the purified water so that the water temperature is 20 to 43 ° C. Norovirus is killed by bringing warm water into contact with norovirus and bringing warm water into contact with norovirus discharged from the shellfish due to the bioactivity of bivalves.

  It is known that norovirus loses its activity when exposed to high temperatures, and eventually dies. According to this solution, norovirus can be killed by allowing bivalves to exist in warm water. In this case, the water temperature in the septic tank is set to a predetermined temperature between 20 and 43 ° C. That is, it is a range in which the physiological activity of the bivalve is performed and is set to a relatively high value. For this reason, it is possible to reduce the number of norovirus in the shellfish and the number of surviving norovirus in the septic tank by bringing warm water into contact with the norovirus inside and outside the shellfish while discharging the norovirus due to the bioactivity of the bivalve shellfish. it can. The reason for managing the purified water at the above temperature is that if the temperature of the purified water is less than 20 ° C., the water temperature is too low to kill Norovirus, and if the temperature of the purified water exceeds 43 ° C., This is because heat denaturation occurs in the bivalve protein and physiological activity becomes impossible.

  Moreover, the purification apparatus for implementing this bivalve purification method is also within the scope of the technical idea of the present invention. That is, it is a purification apparatus provided with the purification tank which stored purified water, and the temperature adjustment means which adjusts temperature so that the temperature of this purified water may be 20-43 degreeC.

  Specific items added to enhance the purification effect of bivalves include the following. First, the residual chlorine concentration of the purified water in the septic tank is set to 0.3 ppm or less. If the residual chlorine concentration of the purified water exceeds 0.3 ppm, the bivalve may stop the physiological activity and the virus discharge operation may not be performed. For this reason, by setting the residual chlorine concentration to 0.3 ppm or less, the virus discharging operation associated with the bioactivity of the bivalve can be reliably performed.

  In addition, the purified water is irradiated with ultraviolet rays. By this ultraviolet irradiation, it is possible to kill the virus that is alive in the purified water (purified water outside the shell) in the septic tank, and to greatly reduce the infectious value of the virus in the entire septic tank.

  In addition, when the bivalve is processed into a strip, the infectivity of the virus can be reduced by the following steps. That is, taking out the purified bivalve from the septic tank and placing it in a sealed container, heating the sealed container to a temperature of 30 ° C. or more and less than 50 ° C., and setting the pressure in the sealed container to less than 100 MPa. It opens the bivalve shell and kills the norovirus in the shellfish. By stripping under such temperature and pressure control, the virus remaining in the shell can be killed and the infectivity of the virus can be reliably reduced.

  Further, a determination method for determining the purification performance by any one of the above-described solving means by the bivalve purification method is also within the scope of the technical idea of the present invention. In other words, using feline calicivirus as an alternative virus for norovirus, and taking feline calicivirus into the bivalve, the bivalve purification method of any one of the above solutions is implemented, and the virus infectivity titer is determined. This is a purification determination method for determining purification performance by measuring.

  In the present invention, the norovirus in the shell is discharged outside the shell by effectively utilizing the physiological activity of the bivalve shell, and the discharged norovirus is killed by the electrolyzed water. In addition, norovirus is constantly exposed to high temperatures and killed by passing temperature-controlled warm water through the bivalves. For this reason, it is possible to obtain a high virus killing effect that could not be realized by conventional sterilization methods (methods using sodium hypochlorite, ultraviolet rays, ozone), and to reliably reduce the number of noroviruses to about 1/1000. Is possible. As a result, viral food poisoning of bivalves can be reliably prevented. In addition, among each of the above-described solutions, the number of noroviruses can be determined by combining the temperature control of the electrolyzed water so that the bivalve has a physiological activity and the stripping process under the temperature and pressure control. Can be reduced to about 1/10000.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment demonstrates the case where this invention is applied in order to purify an oyster as a bivalve.

(First embodiment)
FIG. 1 is a schematic diagram showing an outline of the entire configuration of a purification system 1 as a purification apparatus according to the present embodiment. As shown in this figure, the purification system 1 includes a purification tank 2, a filtration device 3, an electrolysis device 4 as electrolysis means, and a heating device 5 as temperature adjustment means.

  The septic tank 2 is a water tank with an open top, and has a water storage capacity of, for example, several hundred liters, and is sized to allow tens of oysters to live inside. The size of the septic tank 2 is not particularly limited, and may be an upper closed septic tank.

  The filtration device 3 has a hollow membrane inside, and a seawater introduction pipe 31 and a filtrate water supply pipe 32 are connected thereto. One end (downstream end) of the filtered water supply pipe 32 is opened above the septic tank 2. For this reason, the seawater pumped from the pump 33 provided in the seawater introduction pipe 31 passes through the hollow core membrane inside the filtration device 3, and after impurities (dust etc.) are filtered, the filtered water supply pipe 32 is supplied into the septic tank 2. In addition, the seawater supply operation | movement to this septic tank 2 is performed at the time of the start of use of this purification system 1 (before throwing in an oyster). It is also performed when the seawater in the septic tank 2 is replaced or when the amount of seawater in the septic tank 2 is reduced.

  The electrolyzer 4 is connected to the septic tank 2 by a seawater extraction pipe 41 and a seawater return pipe 42 provided with a pump 43. That is, the electrolyzer 4 forms a seawater circulation circuit with the septic tank 2. The electrolyzer 4 includes an electrode (not shown) for electrolyzing the introduced seawater, and the seawater is generated in the electrolyzed water while circulating the seawater between the septic tank 2. It is like that. For example, a platinum electrode is used and electrolysis is performed with a current of about 2 A at a direct current of 10 V.

Further, the electrolysis device 4 is provided with an ultraviolet irradiation device (ultraviolet lamp) 6. That is, the seawater in the electrolyzer 4 is irradiated with ultraviolet rays (for example, 1.0 × 10 ⁴ μW · sec / cm ² ) (irradiation from above the water surface in the electrolyzer 4 or by sinking an ultraviolet lamp in water). By irradiating in water, sterilization and wiping effects can be obtained. For this reason, most of the bacteria and viruses in the seawater (electrolyzed water) returned from the electrolyzer 4 to the septic tank 2 through the seawater return pipe 42 are in a state of being killed by ultraviolet irradiation.

  The warming device 5 is connected to the septic tank 2 by a seawater take-out pipe 51 and a seawater return pipe 52 provided with a pump 53. That is, the heating device 5 forms a seawater circulation circuit with the septic tank 2. The heating device 5 includes a heater (not shown) for heating the introduced seawater to a predetermined temperature, and circulates the seawater between the septic tank 2 and warms the seawater at a predetermined temperature. It is supposed to be generated. Specifically, seawater is generated into 20 ° C. warm water. That is, a temperature sensor is installed in the heating device 5 or in the seawater take-out pipe 51, and the heater is turned on to warm the seawater until the sensing temperature reaches 20 ° C., while the sensing temperature is When the temperature reaches 20 ° C., the heater is turned off. When the sensing temperature falls below 20 ° C., the heater is turned on again to maintain the seawater at a constant temperature. As this heater, an electric heater, a heat pump, or the like can be used.

  Moreover, the seawater temperature set here is not limited to 20 ° C., but is managed at a predetermined temperature within a range of 10 to 43 ° C. This temperature range is the range where physiological activity of oysters (exercise for taking up plankton and oxygen) is performed, and by controlling the seawater temperature within this range, water constantly passes through the oysters. The norovirus in the oyster can be discharged out of the oyster by the water flow. In other words, if the seawater temperature is less than 10 ° C, the physiological activity of the oysters will not be performed, and norovirus will not be discharged. If the seawater temperature exceeds 43 ° C, heat denaturation will occur in the oyster protein. Virus discharge operation due to physiological activity is disabled. For this reason, seawater temperature is managed in the range of 10-43 degreeC.

  The oyster purification operation in the purification system 1 configured as described above is as follows. First, before feeding oysters into the septic tank 2, an operation of supplying seawater to the septic tank 2 is performed. In this operation, the pump 33 provided in the seawater introduction pipe 31 is activated, and the seawater pumped up from the pump 33 is introduced into the filtration device 3, and impurities are filtered by passing through the hollow core membrane. Then, it is supplied into the septic tank 2 through the filtered water supply pipe 32. Then, the pump 33 is stopped when a predetermined amount of seawater is stored in the septic tank 2.

  Thereafter, a predetermined number of oysters are put into the septic tank 2. At the same time, the electrolyzer 4 and the heating device 5 are started. That is, in the electrolysis apparatus 4, the pump 43 provided in the seawater take-out pipe 41 is activated, and this seawater is generated in the electrolyzed water while circulating the seawater between the septic tank 2. Moreover, in this electrolysis apparatus 4, ultraviolet irradiation is performed with respect to seawater from the ultraviolet irradiation apparatus 6, and sterilization and virus destruction are performed. On the other hand, in the heating device 5, the pump 53 provided in the seawater take-out pipe 51 is activated, and this seawater is generated into warm water at 20 ° C. while circulating the seawater between the septic tank 2.

  By continuing such an operating state, the inside of the septic tank 2 will be in the state where the oysters inhabited in the electrolyzed water temperature-controlled at 20 degreeC. For this reason, the oyster takes in the electrolyzed water in the septic tank 2 into the shell and discharges the electrolyzed water in the shell due to its physiological activity. That is, cilia movement is performed to filter out plankton in the water and absorb oxygen. Thereby, the electrolyzed water passes through the inside of the oyster, and with this passage, the norovirus in the oyster is discharged to the outside of the oyster together with the water flow, and the inside of the oyster is purified. In addition, the discharged norovirus is always in contact with the electrolyzed water and is killed by the action of the electrolyzed water. For this reason, the number of noroviruses present in the electrolyzed water newly taken into the shell is also reduced, and the infectivity value of norovirus can be greatly reduced. In this embodiment, this purification operation is continuously performed for about 20 hours.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. The purification system 1 according to this embodiment is different from that of the first embodiment in that the electrolysis apparatus 4 is not provided. That is, the oyster is purified only by the temperature control of the seawater in the septic tank 2. Therefore, only seawater temperature management will be described here.

  In the purification system 1 according to this embodiment shown in FIG. 2, the warming device 5 manages the seawater temperature at a predetermined temperature within a range of 20 to 43 ° C. Specifically, it is set to 30 ° C. The seawater temperature set here is not limited to 30 ° C., but is managed at a predetermined temperature within a range of 20 to 43 ° C. This temperature range is a relatively high value in the range in which oyster physiological activity (exercise for taking up plankton and oxygen) is performed. For this reason, the number of norovirus in the oyster and the number of surviving norovirus in the septic tank 2 can be reduced by bringing warm water into contact with the norovirus inside and outside the oyster while allowing the norovirus to be discharged due to the physiological activity of the oyster. Can do. The reason for controlling the purified water at the above temperature is that when the seawater temperature is less than 20 ° C, the water temperature is too low to kill Norovirus, and when the seawater temperature exceeds 43 ° C, it is heat-denatured into oyster protein. The virus discharge operation due to physiological activity becomes impossible. For this reason, seawater temperature is managed in the range of 20-43 degreeC.

  According to this embodiment, the norovirus is always exposed to a high temperature, and the norovirus loses its activity by the heat energy received from the hot water and can then be killed.

(Striped processing)
Next, stripping processing for reducing the infectious value of a virus when processing the oyster purified in the purification system 1 according to the first embodiment or the second embodiment described above into stripping will be described.

  In this stripping processing, the oyster taken out from the septic tank 2 after the purification is placed in a sealed container, the inside of the sealed container is heated to a temperature of 30 ° C. or more and less than 50 ° C., and the pressure in the sealed container is set to less than 100 MPa. By doing so, oysters are opened. In other words, the heat denaturation that occurs in the protein of the oyster body is heated to a temperature below the limit temperature where it is reversible, and the pressure at which the joint between the oyster shell and outer shell is released acts at this temperature. I have to. By stripping in such an environment, the norovirus inside the oyster can also be killed, and the infectivity of the virus can be reliably reduced.

  Specifically, when the water temperature is 30 ° C., the open shell starts even if the pressure in the sealed container is about 70 MPa, and when the water temperature is 40 ° C., the pressure in the sealed container is about 60 MPa. Even if there is, the opening of the shell starts, and when the water temperature is 50 ° C., the opening of the shell starts even if the pressure in the sealed container is 50 MPa or less.

  In particular, when the water temperature is 30 ° C., even if the pressure in the sealed container is 80 MPa, 95% of oysters are opened, and all of them reach shelling. Further, when the water temperature is 40 ° C., 97% of oysters are opened even if the pressure in the sealed container is 70 MPa, and all of them reach shelling. Further, when the water temperature is 50 ° C., 97% of oysters are opened even if the pressure in the sealed container is 60 MPa, and most of them reach the shelling. However, when the water temperature is 50 ° C., the protein contained in the body of the oyster may cause irreversible thermal denaturation, so it is not preferable to perform the open shell in this temperature range. Actually, it is preferable to use a pressure range where the open shell ratio is 95% or more when the water temperature is in the range of 30 ° C to 45 ° C. For example, when the water temperature is 30 ° C., the pressure inside the sealed container is set to 80 MPa, when the water temperature is 40 ° C., the pressure inside the sealed container is set to 70 MPa, and when the water temperature is 45 ° C. The pressure in the closed container is set to about 65 MPa. In these cases, since most oysters reach not only the open shell but also the shell removal, there is almost no need to unshell the oyster taken out from the sealed container. In addition, if it is not necessary to bring most oysters to shelling and only open shells are required, a slightly lower temperature and lower pressure may be applied to oysters. Even when only this open shell is performed, since the joint portion between the oyster closed shell muscle and the outer shell is already in a state of being easily detached, the shelling operation can be performed very easily.

-Experimental example-
The results of experiments conducted to support the effects of the above-described embodiments will be described below. As described above, since norovirus grows only in human intestinal cells, it is difficult to realize its culture environment, and a culture technique has not yet been established. For this reason, the inventors of the present invention examined alternative viruses and conducted experiments using feline calicivirus as an alternative virus for this norovirus. In other words, the purification determination was performed in a state where feline calicivirus was incorporated into the oyster (for example, several hundreds).

  FIG. 3 shows the experimental results regarding the temperature stability of feline calicivirus. In this experiment, the temporal change of the virus infectivity value was measured for the water temperature of the septic tank 2 set to 5 ° C., 10 ° C., 20 ° C. and 37 ° C., respectively.

  As can be seen from FIG. 3, it was confirmed that when the water temperature of the septic tank 2 exceeds 20 ° C., the virus infectivity can be significantly reduced in a short time. That is, the temperature setting range managed in the second embodiment can be confirmed.

  FIG. 4 shows the experimental results regarding the sensitivity of feline calicivirus to electrolyzed water. In this experiment, electrolyzed water having a residual chlorine concentration of 0.23 mg / L was used as seawater in the septic tank 2, and the temporal change in virus infectivity was measured.

  As can be seen from FIG. 4, when 1 minute has passed as the processing time, the viral infectivity titer was confirmed to decrease by more than two digits. That is, the effect of using electrolyzed water in the first embodiment can be confirmed.

  FIG. 5 shows the experimental results regarding the ultraviolet sensitivity of feline calicivirus. In this experiment, ultraviolet rays were irradiated to seawater containing feline calicivirus, and the relationship between the irradiation amount and the virus infectivity was measured.

  As can be seen from FIG. 5, it was confirmed that the virus infectivity titer was lowered by irradiating with ultraviolet rays. In particular, the decrease rate of the virus infectivity value increases as the irradiation amount increases. That is, the effect of irradiating the seawater with ultraviolet rays in the first embodiment can be confirmed.

  FIG. 6 shows the results of experiments on the stability of feline calicivirus under high water pressure. In this experiment, when the oysters were stripped, the virus infection titer was measured when the treatment time was set at 5 minutes for those in which the environmental pressure was set to 0 MPa, 80 MPa, 200 MPa, and 300 MPa in an environment of 40 ° C.

  As can be seen from FIG. 6, it was confirmed that the higher the environmental pressure, the lower the virus infectivity. In other words, it has been proved that the infectivity value of the virus can be reduced even by the stripping processing under the above-described conditions.

-Other embodiments-
Each embodiment described above demonstrated the case where this invention was applied as a purification method, a purification determination method, and a purification apparatus for purifying oysters. The present invention is not limited to this, and can also be applied as a purification method, a purification determination method, and a purification device for purifying other bivalves (such as shallow shellfish and scallops).

  Moreover, it is good also as a structure by which the filter apparatus 3 in the purification system 1 which concerns on each embodiment mentioned above is equipped with an electrode, and electrolyzed water is produced | generated also in this filter apparatus 3. FIG.

It is a schematic diagram which shows the outline of the whole structure of the purification system which concerns on 1st Embodiment. It is a schematic diagram which shows the outline of the whole structure of the purification | cleaning system which concerns on 2nd Embodiment. It is a figure which shows the experimental result regarding the temperature stability of a feline calicivirus. It is a figure which shows the experimental result regarding the electrolysis water sensitivity of a feline calicivirus. It is a figure which shows the experimental result regarding the ultraviolet sensitivity of a feline calicivirus. It is a figure which shows the experimental result regarding the stability of the feline calicivirus under high water pressure.

Explanation of symbols

1 Purification system (Purification device)
2 Septic tank 4 Electrolytic device (electrolytic means)
5 Heating device (temperature adjustment means)

Claims (8)

A method for purifying bivalves by discharging or killing norovirus that has been taken inside bivalves,
Put the bivalve in a septic tank that stores purified water consisting of seawater, and control the temperature of the purified water as warm water so that the water temperature is 30-43 ° C, so that the warm water is brought into contact with the norovirus incorporated in the bivalve In addition, by passing purified water through the bivalve in accordance with the bivalve physiological activity, the norovirus in the shell is discharged out of the shell together with the water flow, and the warm water is brought into contact with the norovirus discharged outside the shell. A method for purifying bivalves, characterized by killing norovirus.   The bivalve purification method according to claim 1, wherein the purified water is electrolyzed water obtained by electrolyzing seawater. In the purification method of the bivalve according to claim 1 or 2 ,
A method for purifying a bivalve, characterized in that the residual chlorine concentration of purified water in the septic tank is set to 0.3 ppm or less. In the purification method of the bivalve according to any one of claims 1 to 3 ,
A method for purifying bivalves, wherein the purified water is irradiated with ultraviolet rays. The bivalve purified by the bivalve purification method according to any one of claims 1 to 4 is taken out of the septic tank and placed in a sealed container, and the temperature of the sealed container is 30 ° C or higher and lower than 50 ° C. A method for purifying a bivalve, characterized by opening the bivalve by heating and setting the pressure in the sealed container to less than 100 MPa, and killing norovirus in the clam. A determination method for determining purification performance by the bivalve purification method according to any one of claims 1 to 5 ,
The feline calicivirus is used as a substitute virus for norovirus, and the bivalve purification method according to any one of claims 1 to 5 is carried out in a state in which the feline calicivirus is incorporated into the bivalve, and the virus infection A method for determining the purification of a bivalve, wherein the purification performance is determined by measuring the value. A purification device for purifying bivalves by discharging or killing norovirus that has been taken inside bivalves,
A septic tank storing purified water composed of seawater ;
A bivalve purification apparatus comprising temperature adjusting means for adjusting the temperature of the purified water to be 30 to 43 ° C. The bivalve purification apparatus according to claim 7, further comprising an electrolyzing means for generating electrolyzed water by electrolyzing the purified water.

Images