WO2022191072A1

WO2022191072A1 - Shellfish cleaning method and cleaning apparatus

Info

Publication number: WO2022191072A1
Application number: PCT/JP2022/009451
Authority: WO
Inventors: 進藤川
Original assignee: 有限会社ターレス
Priority date: 2021-03-08
Filing date: 2022-03-04
Publication date: 2022-09-15
Also published as: JPWO2022191072A1

Abstract

The present invention pertains to: a shellfish cleaning method characterized by removing residual microplastics in the bodies of live shellfish by immersing the shellfish having the residual microplastics in the bodies thereof, in artificial seawater containing microbubbles and satisfying the growing condition of said shellfish; and a shellfish cleaning apparatus that is suitable for implementing said method. The present invention provides: a shellfish cleaning method that enables efficient removal of microplastics from bodies of shellfish, by cleaning live shellfish having residual microplastics included in the bodies thereof by using artificial seawater containing microbubbles; and a shellfish cleaning apparatus that is suitable for implementing the cleaning method.

Description

Shellfish cleaning method and cleaning device

The present invention provides a method for cleaning shellfish that removes microplastic from the body of the shellfish by immersing the live shellfish with microplastics remaining in the body in artificial seawater containing microbubbles, and implementation of this method. It relates to a cleaning device for shellfish suitable for

Microplastics are tiny plastic particles that exist in the environment, and in recent years have become a very big problem in the marine environment. Microplastics have the property of easily adsorbing contaminants. Therefore, when marine organisms ingest microplastics themselves and accompanying harmful substances (PCB, DDT, etc.), there is concern that bioaccumulation will affect the health of seabirds and humans.

Shellfish such as turban shells, oysters, and abalones, which are marine organisms, have been produced in large quantities and served as food due to recent developments in aquaculture technology. For example, oysters are not limited to being eaten raw or processed, but are peeled from the oyster shell and washed.
Conventional washing methods include a method of washing raw oysters and the like using electrolyzed water of an electrolytic aqueous solution of caustic soda and salt (Patent Document 1), a method of spraying microbiocidal seawater on oyster shells (Patent Document 2), A method of soaking oysters in water containing ozone and a method of irradiating oysters with ultraviolet rays to remove bacteria are known.
However, with these conventional methods, it is difficult to remove microplastics remaining in the living body, which has become a problem in recent years.

JP-A-2002-259755 JP 2019-83791 A

The present invention has been made in view of the above problems, and is intended to easily and efficiently remove microplastics remaining in the body (in the digestive tract) of shellfish such as oysters, thereby improving the food safety of marine organisms such as shellfish. It is an object of the present invention to provide a method for cleaning live shellfish that have microplastics remaining in their bodies, and a cleaning apparatus for shellfish that is suitable for carrying out this method.

As a result of intensive studies to solve the above problems, the present inventors immersed live oysters, which are a type of shellfish, in artificial seawater containing microbubbles, and left them for 10 to 30 minutes under oyster growing conditions. As a result, the microplastics are discharged from the body together with the undigested plankton accumulated in the oyster's body, and as a result, the microplastic remaining in the oyster's body can be removed. By generalizing this knowledge, the present invention was completed.

Thus, according to the present invention, the following methods (1) and (2) for cleaning shellfish and (3) to (7) for cleaning shellfish are provided.
(1) Removing the microplastics remaining in the body of the shellfish by immersing the live shellfish with microplastics remaining in the body in artificial seawater containing microbubbles and satisfying the growth conditions of the shellfish. A method for cleaning shellfish characterized by:
(2) The shellfish according to (1), wherein the living shellfish with microplastics remaining in the body is immersed in artificial seawater containing microbubbles and satisfying the growth conditions of the shellfish for 10 to 30 minutes. cleaning method.

(3) Shellfish removal of microplastics remaining in the body of the shellfish by immersing the living shellfish with microplastics remaining in the body in artificial seawater that contains microbubbles and satisfies the growth conditions of the shellfish. A cleaning device,
A washing tank for washing shellfish using artificial seawater containing microbubbles and satisfying the growth conditions of shellfish;
A microbubble generating mechanism for preparing artificial seawater containing microbubbles and satisfying the growth conditions of shellfish, and
a nozzle that is installed at the bottom of the washing tank and that discharges artificial seawater containing microbubbles that is fed from the microbubble generating mechanism and that satisfies the growth conditions of shellfish;
Shellfish washing device with.
(4) Live shellfish with microplastics remaining in their bodies are immersed in artificial seawater containing no microbubbles that satisfies the growth conditions for shellfish and stored in the washing tank, and microbubbles are removed from the nozzle. The apparatus for washing shellfish according to (3), which discharges artificial seawater that contains and satisfies the growth conditions of shellfish.
(5) The washing apparatus for shellfish according to (3) or (4), further comprising a contaminated water storage tank for storing contaminated water containing microplastics discharged from the upper part of the washing tank.
(6) immersing a predetermined amount of live shellfish containing microplastics in the artificial seawater that satisfies the growth conditions of shellfish and does not contain microbubbles stored in the washing tank; (3) to (5), wherein artificial seawater containing microbubbles and satisfying the growth conditions of shellfish is discharged, and at the same time, contaminated water containing microplastics is discharged from the upper part of the washing tank. A cleaning apparatus for shellfish according to any one of the above.
(7) Live shellfish with microplastics remaining in the body are immersed in artificial seawater that contains microbubbles and satisfies the growth conditions of shellfish for 10 to 30 minutes. (3) to (6) Shellfish cleaning apparatus according to any one of.

When live shellfish are immersed in artificial seawater that contains microbubbles and meets the growth conditions for shellfish, the shellfish takes in the artificial seawater containing microbubbles into its body. Then, in shellfish, microbubbles bind to microplastics that accumulate in the body. The microbubbles that have adsorbed the microplastics are discharged from the body together with the artificial seawater discharged from the shellfish. Microbubbles adsorbing microplastics discharged from the body disappear in the water while floating, causing dirt such as microplastics to rise to the surface of the water.

The present invention is based on this principle, and a simple method of immersing live shellfish in artificial seawater containing microbubbles that satisfies the growth conditions of shellfish and allowing the shellfish to stand for a predetermined period of time enables the growth of shellfish. A method for cleaning shellfish that allows microplastics accumulated in the body to be discharged from the body and, as a result, to efficiently remove microplastics remaining in the body of shellfish, and a cleaning method for shellfish that is suitable for carrying out this method. It provides an apparatus.
According to the present invention, a method for washing shellfish that efficiently removes microplastics from the bodies of shellfishes by washing living shellfishes in which microplastics remain in the bodies using artificial seawater containing microbubbles, and , a shellfish cleaning apparatus suitable for carrying out this cleaning method is provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows an example of the washing|cleaning apparatus of the shellfish of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows an example of the washing|cleaning apparatus of the shellfish of this invention. It is a schematic diagram which shows the state which wash|cleans shellfish using the washing|cleaning apparatus of shellfish shown in FIG.

I. Method for washing shellfish The method for washing shellfish of the present invention comprises immersing live shellfish in which microplastics remain in the body in artificial seawater containing microbubbles and satisfying the conditions for the growth of shellfish. characterized by removing microplastics remaining in the
Hereinafter, the method for cleaning shellfish of the present invention will be described in detail.

(Shellfish to be Washed)
The shellfish to be cleaned in the present invention is not particularly limited as long as it is marine (seafood) and contains microplastics remaining in the body, but edible shellfish are preferred. For example, turban shells, abalone, short-necked clams, clams, red clams, oysters, hard clams, surf clams, glass mussels, razor clams, mussels, and the like.
The amount of living shellfish to be immersed in artificial seawater is not particularly limited as long as it is an amount that can be washed.
The temperature at which the shellfish are immersed may be any temperature at which the shellfish can survive, and is usually about 10 to 25°C.

(artificial seawater)
In the present invention, artificial seawater (hereinafter sometimes simply referred to as "artificial seawater") that satisfies the growth conditions of shellfish is used.
Natural seawater often contains microplastics. Therefore, in the present invention, it is preferable to use artificial seawater that does not contain microplastics and satisfies the growth conditions of shellfish.

“Artificial seawater that satisfies the growth conditions of shellfish” means artificial seawater that allows shellfish to grow in the artificial seawater even when the shellfish are immersed in the artificial seawater. That is, when the shellfish is immersed in the artificial seawater, the shellfish does not die in the artificial seawater, the artificial seawater is taken into the body, and the taken-in artificial seawater is repeatedly discharged outside the body. Sea water.
As the artificial seawater that satisfies the growth conditions of shellfish, salt water containing salts similar to those contained in seawater at a salt concentration similar to that of seawater may be used.
The salinity of seawater is 3-3.5% by weight. That is, artificial seawater is water containing salts with a salt concentration of 3 to 3.5% by weight. Salts are contained in seawater, and include table salt (NaCl), magnesium chloride (MgCl ₂ ), magnesium sulfate (MgSO ₄ ), calcium sulfate (CaSO ₄ ), potassium chloride (KCl), and the like.

Artificial seawater can be prepared by adding a predetermined amount of salts similar to those contained in seawater to water so that the salt concentration is approximately the same as that of seawater, and dissolving them.
Water used for preparing artificial seawater preferably does not contain bleaching powder, trihalomethane, or the like.
For example, when tap water is used, since tap water contains bleaching powder, water prepared by any of the following methods can be used.
(a) Water obtained by immersing about 150 g of charcoal in tap water for 1 liter of tap water and leaving it overnight (b) Water obtained by adding about 1 g of Hypo (sodium thiosulfate) to 40 liters of tap water (c) Water obtained by dripping 2 or 3 drops of lemon juice per liter of tap water, mineral water, or water obtained by drawing tap water and letting it stand for 6 to 24 hours while exposing it to sunlight. Water obtained by passing tap water through a water purifier may also be used. Also, natural seawater that does not contain microplastics can be used. For example, natural seawater from which microplastics have been removed by passing the natural seawater through a layer of sand (filtering through a layer of sand) can be used.

(micro plastic)
The present invention is a method for cleaning shellfish by cleaning live shellfish in which microplastics remain in the body to remove the microplastics from the body of the shellfish.
Microplastics that are washed away are tiny plastic particles present in the environment. The size of microplastics is usually less than 5 mm. Since the object of the present invention is to remain in the body of shellfish, all plastic particles smaller than 1 mm in size that can be observed under a microscope (or an electron microscope) are referred to as plastic particles.

The extent to which microplastics remaining in the bodies of living shellfish have been removed can be confirmed, for example, by observing the internal organs of shellfish before and after washing with the naked eye, microscope, or electron microscope. It can also be confirmed by collecting artificial seawater (contaminated water) containing microbubbles used for washing and observing it visually, with a microscope, or with an electron microscope.

<Microbubble>
The present invention uses artificial seawater containing microbubbles for washing live shellfish.
Microbubbles are fine air bubbles with a diameter of 50 μm or less, and unlike ordinary air bubbles, they have the property of shrinking and disappearing (crushing) in water. The microbubbles are charged with negative ions, and are combined with dirt (microplastics, etc.), which are positive ions, and disappear in the water while floating, allowing the dirt to float to the surface of the water.
In order to obtain artificial seawater containing microbubbles, a mechanism for generating microbubbles, which will be described later, is usually used. Since water has a high surface tension, it is impossible to generate bubbles of 100 μm or less by normal bubbling.

Artificial seawater containing microbubbles can be prepared using a microbubble generation mechanism.
The microbubble generating mechanism is not particularly limited as long as it can generate microbubbles, and any known mechanism can be used. For example, a venturi tube (a tube having a partially constricted structure) or an orifice plate (doughnut-shaped plate with a hole in the center) is used to generate microbubbles in a discharge port (Japanese Patent Application Laid-Open No. 2006-116518). Publication, Japanese Patent Application No. 2006-77553, etc.): A device that discharges a liquid mixed with a gas into a main pipe placed in the liquid and causes it to collide with a collision wall placed downstream in the main pipe to generate microbubbles. (Japanese Unexamined Patent Application Publication No. 2005-334869); A device that generates microbubbles by blowing pressurized air into water through a fine mesh member or a porous plate using a pneumatic source such as an air pump (Japanese Unexamined Patent Application Publication No. 2006- 68631, etc.); A device that creates a swirl water flow and shears air with this water flow to generate microbubbles (JP 2003-126665, etc.); Microbubble generation described in JP 2009-273990 nozzle; and the like.

(Method for washing shellfish)
More specifically, the method for cleaning shellfish of the present invention is carried out by the following procedure.
(Step 1) A predetermined amount of live shellfish to be washed is immersed in artificial seawater.
(Step 2) Microbubbles are added to the artificial seawater in which the shellfish are immersed.
(Step 3) After containing the microbubbles, the live shellfish is further immersed in the artificial seawater containing the microbubbles for a predetermined time, preferably 10 to 30 minutes. If necessary, the operation of immersing live shellfish in artificial seawater containing microbubbles for a predetermined period of time may be repeated multiple times.
Steps 1 to 3 can be performed using a shellfish cleaning apparatus described later.

2. The shellfish cleaning apparatus of the present invention is a shellfish cleaning apparatus in which live shellfish with microplastics remaining in their bodies are immersed in artificial seawater containing microbubbles, which satisfies the growth conditions of shellfish. A cleaning apparatus for shellfish for removing microplastics remaining in a shellfish, comprising: a cleaning tank storing artificial seawater containing microbubbles and satisfying the conditions for growing shellfish; and an artificial seawater containing microbubbles and satisfying the conditions for growing shellfish. A microbubble generating mechanism that prepares seawater, and a nozzle that is installed at the bottom of the washing tank and discharges the artificial seawater sent from the microbubble generator.
The shellfish cleaning apparatus of the present invention is suitable for carrying out the shellfish cleaning method of the present invention.

An example of the shellfish cleaning apparatus of the present invention is shown in FIG.
In FIG. 1, 1 is a washing tank for storing artificial seawater (artificial seawater containing microbubbles), 2 is artificial seawater that satisfies the growth conditions of shellfish containing microbubbles, 3 is a microbubble generating mechanism, and 4 is microbubbles. A hose for supplying artificial seawater containing bubbles, 5 a hose insertion port for supplying artificial seawater containing microbubbles, 6 a nozzle for discharging artificial seawater containing microbubbles, 7 a polluted water outlet, and 8 A contaminated water discharge hose, 9 a contaminated water storage tank, 10 a container in which shellfishes for cleaning are placed, and 11 shellfishes for cleaning.

First, put artificial seawater into washing tank 1. The temperature of the artificial seawater may be any temperature at which shellfish can survive, and is usually 10°C to 25°C.

Next, the shells 11 for cleaning placed in the container 10 are immersed together with the container 10 in the artificial seawater stored in the cleaning tank 1 . In FIG. 1, live oysters are used as shellfish 11 for cleaning. In this case, the container 10 should be installed in a state floating from the bottom surface of the cleaning tank 1 (in the intermediate printing state, for example, about 5 cm to 50 cm above the bottom surface of the cleaning tank) to obtain a more excellent effect of the present invention. It is preferable from the viewpoint of obtaining
The size of the washing tank 1 is not particularly limited as long as it has a depth and a bottom area that allow the container 10 containing live shellfish to be immersed therein.

Examples of containers 10 for placing live shellfish include trays (boxes with a shallow bottom), strainers, and baskets. The tray may have a perforated mesh bottom. Also, if the washing tank 1 is sufficiently large, a plurality of containers containing live shellfish can be placed in the artificial seawater.

The amount of shellfish to be immersed is not particularly limited as long as it can be washed.
Artificial seawater containing microbubbles prepared by the microbubble generating mechanism 3 is discharged from the nozzle 6 there.

In this state, the artificial seawater containing microbubbles is continuously discharged from the nozzle 6 for preferably 10 to 30 minutes, more preferably 15 to 25 minutes. As a result, the inside of the washing tank 1 is filled with artificial seawater containing microbubbles. At the same time, artificial seawater (contaminated water) containing microplastics is discharged from the contaminated water discharge port 7 provided at the top of the washing tank 1 . The discharged contaminated water is stored in the contaminated water storage tank 9 .

While the artificial seawater containing microbubbles is discharged from the nozzle 6, the living shellfish 11 repeats taking the artificial seawater containing microbubbles into the body and discharging the artificial seawater taken into the body to the outside of the body again. .
At this time, the microplastics accumulated in the body (internal organs) of the shellfish are adsorbed by the microbubbles and discharged out of the shellfish body together with the artificial seawater. Microbubbles adsorbing microplastics discharged from the body disappear in the water while floating, causing dirt such as microplastics to rise to the surface of the water. Contaminated water containing microplastics passes through a contaminated water discharge port 7 and a contaminated water discharge hose 8 and is sent to a contaminated water storage tank 9 .
At this time, the water surface of the washing tank 1 storing the artificial seawater forms a flow of water from the opposite direction of the contaminated water outlet 7 toward the contaminated water outlet 7, and the contaminated water containing microplastics is contaminated. It is preferable that the water is discharged efficiently from the water outlet. As a method of forming a water flow from the opposite direction of the contaminated water outlet 7 toward the contaminated water outlet 7, an air hole (not shown) is formed on the opposite side of the contaminated water outlet 7 of the cleaning tank 1. a method of blowing air from there toward the contaminated water discharge port 7; .

The contaminated water storage tank 9 may be equipped with a filter and have a structure that can separate microplastics from artificial seawater. Artificial seawater that has been separated from microplastics can be reused as washing water for shellfish.

In addition, in the shellfish cleaning apparatus shown in FIG. 1, a belt conveyor is installed on the bottom of the storage tank 1, and while artificial seawater containing microbubbles is discharged from the nozzle 6, the container on which the shellfish is placed moves on the belt conveyor. It may be transported. According to this method, the container moves on the belt conveyor by adjusting the conveying speed so that the container moves slowly on the belt conveyor over the time required for washing (10 to 30 minutes). In the meantime, the washing of the shellfish placed in the container can be completed. The method of installing the belt conveyor is not particularly limited. For example, in the cleaning apparatus shown in FIG. 1, a belt conveyor extending from the right side to the left side in FIG. By moving from the right side to the left side in FIG. You may make it take it out intentionally.

Another example of the shellfish cleaning apparatus of the present invention is shown in FIG.
In FIG. 2, 1 is a washing tank for storing artificial seawater (artificial seawater containing microbubbles), 2 is artificial seawater that satisfies the growth conditions of shellfish containing microbubbles, 3 is a microbubble generating mechanism, and 4 is a microbubble generating mechanism. 5 is a hose insertion port for supplying artificial seawater containing microbubbles, 6 is a nozzle for discharging artificial seawater containing microbubbles, 7 is a contaminated water outlet, 8 is polluted A hose for water discharge, 9 a contaminated water storage tank, 10a a container for placing shellfish for washing, 12 a rope for hanging the container 10a, and 13 a top plate for fixing the rope 12.

First, artificial seawater is put into the washing tank 1.
The size of the washing tank 1 is not particularly limited as long as it has a depth and a bottom area that allow the container 10a containing live shellfish to be immersed in a suspended state.
Also, if the washing tank 1 is sufficiently large, a plurality of containers 10a containing live shellfish can be placed in the artificial seawater.
The temperature of the artificial seawater may be any temperature at which shellfish can survive, and is usually 10°C to 25°C.

The container 10a is a container for containing live shellfish for washing, and allows artificial seawater containing microbubbles to freely pass through the inside of the container. In FIG. 2, the container 10a has a cylindrical structure with an opening at the top, and the side surface and the bottom have a mesh-like structure, but is not limited to this, and has an opening at the top and a bottom. It may also have a polygonal columnar structure with a mesh structure on the side surface, or may have a colander shape (bowl shape). Furthermore, the container 10a is not limited to the above, and may be a bag-shaped net having a mesh structure, or a planar structure such as a net for grilling.

Next, as shown in FIG. 3, the shellfish 11 for washing is placed in the container 10a suspended in the artificial seawater by the rope 12 and fixed.

The amount of shellfish stored in the container 10a depends on the size of the container 10a, but is not particularly limited as long as it is an amount that can be washed.

Artificial seawater containing microbubbles prepared by the microbubble generating mechanism 3 is discharged therefrom from a nozzle 6 installed on the bottom of the washing tank 1 .
In this state, the artificial seawater containing microbubbles is continuously discharged from the nozzle 6 for 10 minutes to 30 minutes, preferably 15 minutes to 25 minutes. As a result, the inside of the washing tank 1 is filled to a predetermined depth with artificial seawater containing microbubbles.

While the artificial seawater containing microbubbles is discharged from the nozzle 6, the living shellfish 11 repeats taking the artificial seawater containing microbubbles into the body and discharging the artificial seawater taken into the body to the outside of the body again. .
At this time, the microplastics accumulated in the body (internal organs) of the shellfish are adsorbed by the microbubbles and discharged out of the shellfish body together with the artificial seawater. Microbubbles adsorbing microplastics discharged from the body disappear in the water while floating, causing dirt such as microplastics to rise to the surface of the water.
At the same time, the artificial seawater containing microplastics is discharged from the contaminated water discharge port 7 provided near the top of the contaminated water washing tank 1 through the contaminated water discharge hose 8 . The discharged contaminated water is stored in the contaminated water storage tank 9 .

(Example 1)
Raw oysters were washed using the washing apparatus shown in FIG.
Artificial seawater (water temperature: 10°C) was stored up to a depth of 40 cm in a washing tank measuring 90 cm long, 1.2 m wide, and 60 cm deep. Next, raw oysters (8 pieces) were placed in the container 10a, and the container 10a was suspended in the artificial seawater of the washing tank 1 with a rope 12 and fixed. Then, as shown in FIG. 3, an operation of discharging artificial seawater containing microbubbles from the nozzle of the microbubble generator for 10 minutes was performed twice, and the mixture was allowed to stand for 20 minutes.
After the washing was finished, artificial seawater was sampled near the polluted water outlet 7 of the washing tank 1, and as a result of visual observation, it was confirmed that the sampled artificial seawater contained microplastics.
Artificial seawater before washing does not contain microplastics. After washing the raw oysters with microbubbles, the artificial seawater contains microplastics. was confirmed to have been discharged to

1 Washing tank 2 Artificial seawater containing microbubbles and meeting conditions for growing shellfish 3 Microbubble generating mechanism 4 Artificial seawater supply hose 5 Artificial seawater supply hose insertion port 6 Nozzle 7 Contaminated water discharge port 8 Contaminated water discharge hose 9 Contaminated water storage tank 10 Container 10a for placing shellfish for washing・Container 11 for storing shellfishes for cleaning...shellfishes for cleaning 12...rope 13 for fixing container 10a suspended in artificial seawater...top plate for fixing rope 12

Claims

Live shellfish with microplastics remaining in the body are immersed in artificial seawater that contains microbubbles and satisfies the growth conditions of the shellfish, thereby removing the microplastic remaining in the body of the shellfish. Shellfish cleaning method.
2. The method for cleaning shellfish according to claim 1, wherein the live shellfish with microplastics remaining in the body is immersed in artificial seawater containing microbubbles and satisfying conditions for growing shellfish for 10 to 30 minutes. .
A cleaning apparatus for shellfish that removes microplastics remaining in the body of the shellfish by immersing the live shellfish with microplastics remaining in the body in artificial seawater containing microbubbles that satisfies the growth conditions of the shellfish. There is
A washing tank for washing shellfish using artificial seawater containing microbubbles and satisfying the growth conditions of shellfish;
A microbubble generating mechanism for preparing artificial seawater containing microbubbles and satisfying the growth conditions of shellfish, and
a nozzle installed at the bottom of the washing tank for discharging artificial seawater containing microbubbles, which is fed from the microbubble generator and which satisfies the growth conditions of shellfish;
Shellfish washing device with.
Live shellfish with microplastics remaining in their bodies are immersed in artificial seawater that satisfies the growth conditions of shellfish and does not contain microbubbles, stored in the washing tank, and containing microbubbles from the nozzle, 4. The apparatus for cleaning shellfish according to claim 3, which discharges artificial seawater that satisfies the growth conditions of shellfish.
The cleaning apparatus for shellfish according to claim 3 or 4, further comprising a contaminated water storage tank for storing contaminated water containing microplastics discharged from the upper part of the cleaning tank.
A predetermined amount of live shellfish with microplastics remaining in their bodies is immersed in artificial seawater that meets the growth conditions for shellfish and does not contain microbubbles, stored in the washing tank, and microbubbles are removed from the nozzle. 6. The method according to any one of claims 3 to 5, characterized in that the artificial seawater containing microplastics that satisfies the growth conditions of shellfish is discharged, and at the same time, contaminated water containing microplastics is discharged from the upper part of the washing tank. Shellfish cleaning equipment.
7. The method according to any one of claims 3 to 6, wherein live shellfish in which microplastics remain in the body are immersed for 10 to 30 minutes in artificial seawater containing microbubbles that satisfies the growth conditions of shellfish. Shellfish cleaning equipment.