JP6468812B2 - How to save oysters - Google Patents

Description

  The present invention relates to a method for preserving oysters, and more specifically, by purifying the oysters by pouring deep sea water rich in cleanliness free of pathogenic viruses and bacteria and rich in mineral components (rich in mineral nutrients). The present invention relates to a method for long-term storage of oysters, which can provide oysters that retain or improve the body, freshness, and mineral components of migrant oysters.

Oysters depend on their reproductive form, and the season of oysters is from November to May in Japanese culture. In the second half of the season, in order to begin to have eggs for egg laying in early summer, they eat a lot of food in seawater and grow into fat oysters rich in nutrients. After laying eggs, it will be lean and lean, with only salty taste. For this reason, supply of postcards is difficult from June to October.
In addition, the aquaculture area may be contaminated with viruses and bacteria, and this also has a year-round cycle. For example, the most contaminated area with norovirus is late December to early March. Oysters that circulate such contaminated seawater in the body will be contaminated by taking norovirus in the seawater into the body.
In order to purify such contaminated oysters, purification by animal husbandry is generally adopted, and as a breeding method, it is impossible to grasp the contamination status of individual microorganisms of oysters. In order to remove the surface water, a method of cultivating the surface water for a certain period of time with clean seawater obtained by filtering the surface water or with clean seawater obtained by ultraviolet sterilization is performed (for example, Patent Document 1).

JP 2009-38999 A

However, in such animal husbandry methods, even if attention is paid to purification, it is difficult to completely remove bacteria and particularly microscopic viruses with clean seawater filtered from surface water. In the case of ultraviolet sterilization, there is a problem that a satisfactory purification effect cannot be obtained due to the fact that reliable microorganism-free purified seawater cannot be used due to problems in the apparatus. In addition to this, there is a problem that long-term breeding has the problem that the weight and quality of oysters are impaired, long-term breeding is not possible, and the state of maintaining high quality is at most about 3 days to 1 week. Was the limit.
It is an object of the present invention to provide a storage method capable of adjusting the timing of shipment according to such a situation and shipping oysters that are fresh and not worn according to market demand. Specifically, the following can be mentioned.
That is, the present invention keeps the state of seasonal oysters by landing long-seasoned, fat-rich oysters that begin to have eggs from the beginning of the season, and cultivating them in deep sea water for a long period of time. The goal is to distribute high-quality oysters during the difficult period of supply to the market, even during the off-season of oysters.
In addition, the present invention is highly safe in that oysters are landed before the sea area is contaminated with norovirus, and similarly, the risk of norovirus contamination is reduced as well as maintaining the state by cultivating for a long time in deep sea water. The purpose is to provide oysters.

The inventors have intensively studied to solve the above problems, and found that the above problems can be solved by cultivating oysters for a long time using deep ocean water, thereby completing the present invention.
That is, the present invention is a state in which the quality of oysters is maintained by long-term breeding of oysters that are cultivated by pouring the deep sea water against the oysters in the aquarium at a seawater temperature of 0 to 20 ° C. for 4 days to 6 months. How to save. Moreover, it is preferable that the amount of flowing deep sea water in the aquarium is an amount that rotates the amount of deep sea water corresponding to the volume of the aquarium by 1.0 to 5.0 rotations per day.
In the present invention, it is preferable that the initial deep sea water temperature is 10 to 20 ° C., and then the deep sea water temperature is set to 0 to 9 ° C. The period of raising the seawater at a deep seawater temperature of 10 to 20 ° C. is particularly preferably 4 to 10 days.

When sterilized and purified using aseptic surface water treated with UV sterilization, freshness declined and mineral components declined, but according to the preservation method of long-term oysters using deep ocean water, freshness and In the mineral component, oysters exceeding that of surface water are provided.
Further, according to the preservation method of the oysters by long-term breeding using two deep ocean waters of 2 to 9 ° C. low temperature deep ocean water and 10 to 20 ° C. warm ocean deep water of the present invention, the freshness is maintained. And oysters with high nutritional value are provided.

Graph showing TF production contained in oysters, that is, freshness transition when oysters are cultivated using low-temperature deep seawater, warmed deep seawater, and surface water treated with UV sterilization before breeding and for 1 month and 2 months It is. It is a graph which shows the analysis result of seven types of mineral components contained in oysters when cultivated before and for 10 days using low-temperature deep ocean water, warm deep ocean water, and surface water subjected to ultraviolet sterilization treatment. In the figure, (a) to (g) indicate the contents of sodium, potassium, calcium, magnesium, iron, zinc, and copper, respectively. It is a graph which shows transition of the salt equivalent amount contained in oysters when oysters are cultivated by using low-temperature ocean deep water, warm ocean deep water, and surface water subjected to ultraviolet sterilization before breeding and for 1 month and 2 months. It is a photograph which shows the state of the oyster before and after breeding. In the figure, (a) shows the state of the oysters landed in March, before the slaughter, and (b) shows the state of oysters after slaughtering for 5 months.

The present invention preserves a certain period of time by cultivating oysters for a long period of time using deep sea water in order to adjust the shipping time.
Deep sea water used for animal husbandry in the present invention is seawater pumped from a depth of 200 m to 700 m, and contains inorganic nutrient salts such as oxalate nitrogen, phosphate phosphorus, silicon, etc. Because it is not affected by rivers polluted with substances, there are no pathogenic bacteria or viruses such as viruses that may harm the human body, and it is also chemically clean. Yes. In addition, since phytoplankton that inhabit deep seawater cannot be photosynthesis, inorganic substances that sink from the seawater to the deep layer are not consumed but are accumulated in the deep water. For this reason, deep sea water contains abundant inorganic nutrients that increase the amount of phytoplankton that feeds oysters, and its characteristics are called “inorganic eutrophication”.

  As such deep ocean waters, there are many well-known ocean water intake facilities nationwide, including Nichizen Town, Toyama Prefecture, Kumejima Town, Okinawa Prefecture, and Muroto City, Kochi Prefecture. Deep water can also be used. As described above, all of these deep ocean waters are excellent in cleanliness and inorganic eutrophication. Considering the place where these deep ocean waters are actually bred such as livestock facilities, etc. You can select and use. In use, there is no need for sterilization or filtration, and the collected deep sea water can be used as it is.

  Regarding the use of deep ocean water, the mineral eutrophication of deep ocean water is only the nutritional value for plants that have been photosynthesised so far, and it is suitable for aquaculture and livestock farming using deep ocean water. Although it was not used, for the first time in the present invention, by using this deep ocean water rich in inorganic eutrophication, oysters can be directly ingested by long-term livestock raising, and the nutritional value of oysters can be increased. The preservation method which can maintain the freshness due to cleanliness and stable low temperature could be provided.

  Oysters used for animal husbandry that are subject to preservation in the present invention can be used regardless of the type of domestic oysters, domestic rock oysters, overseas production, and in animal husbandry using these oysters, it is called internal filtration of oysters The characteristics can be fully exhibited.

  Oyster breeding employed in the present invention is performed by introducing deep sea water into a water tank containing oysters and pouring deep sea water. As used herein, “flowing” means that the deep sea water once introduced into the aquarium is not circulated and drained from the drain of the aquarium, but this is not the only case, and the deep sea water is not drained from the drain. It can also overflow from the aquarium.

Oyster breeding is performed by introducing seawater into the aquarium and discharging the same amount of water to the oysters in the aquarium, but the introduction and drainage of seawater can be performed continuously or intermittently. You can go there.
In addition, in order to control the introduction amount and discharge | emission amount of seawater uniformly, apparatuses, such as a normal pump, can be used, and simple methods, such as an overflow, may be employ | adopted.
In addition, the deep ocean water to be introduced can be used as it is without requiring any modification to the deep ocean water in order to fully utilize the cleanliness.
On the other hand, wastewater containing organic matter such as oyster feces after pouring can be reused by processing such as filtration, but rather, it is used for secondary use such as sea cucumber cultivation and seaweed basin regeneration. This is preferred.

  The oysters in the aquarium may be put into the aquarium as they are, or after the oyster is washed under high pressure, or the oysters are submerged in the aquarium alone or to prevent contamination of organic matter accumulated at the bottom of the aquarium. You may raise it after putting it in a container, or raise the bottom and put it in a water tank.

In performing the long-term breeding of oysters of the present invention, the temperature of the deep sea water is preferably about 0 to 20 ° C. The temperature of this deep sea water is divided into cases of low temperature and high temperature depending on the purpose of animal husbandry, and low temperature deep sea water is used to maintain freshness, and the temperature is 0 to 9 ° C. Is preferable, and it is more preferable that it is 2-5 degreeC. Hereinafter, the animal husbandry process for maintaining freshness with this low-temperature deep ocean water is referred to as “freshness-maintaining animal breeding process”. Moreover, in order to raise a mineral component, ie, to raise a nutritive value, the deep sea water heated (it is only called warm deep sea water) is used, The temperature should be 10 degreeC-20 degreeC. Preferably, it is 13 to 16 ° C. Hereinafter, the livestock raising process which raises the nutritional value by raising livestock using this warmed deep ocean water is referred to as “highly nutrientized livestock raising process”. If the temperature of the deep-sea water is outside this range, oyster metabolism tends to become more active when the freshness is maintained, and there is a tendency to consume physical strength. Circulation tends to decrease.
In addition, oysters are purified by raising the body of the oysters when raising them with high-temperature deep sea water in order to increase the nutritional value, thereby obtaining purified oysters that are less contaminated with viruses and bacteria. Therefore, animal husbandry with warm ocean deep water is preferable.

As for the preservation period, in order to ship oysters from November to May in the period from June to October, it is necessary to preserve for about 6 months. The period is preferably about 6 days to 6 months, and more preferably 10 days to 4 months. Beyond this range, there is a possibility that the place of production must be changed to a breeding land due to the item of labeling of the place of notification of the Ministry of Health, Labor and Welfare, “The place of origin is aquaculture with the longest cultivation period,” There is a possibility of losing weight by accumulating energy consumption.
In addition, as for the period of animal husbandry, if it is necessary to raise animals for more than 6 months, oysters with high freshness and high nutritional value can be provided in the same way as oysters for animal raising 6 months. From 6 days to 6 months, the breeding period can be changed according to market trends, and from the viewpoint of storage, storage for about 10 to 12 months is also possible. Of course, although it is not long-term animal husbandry, even if it is animal breeding for less than 4 days, there is no problem, and it is possible to preserve and supply it to the market by raising oysters according to demand.
In addition, for example, when oysters are landed and cultivated before the sea area is contaminated with norovirus, the same can be said, and the culturing period is adjusted according to the shipping time.

Furthermore, in long-term animal husbandry, deep sea water is introduced into and discharged from the aquarium, and the amount of water in the aquarium is kept constant. In the present invention, the value obtained by dividing the total amount of deep sea water introduced into the aquarium in one day by the amount of the aquarium is represented by the number of revolutions as the conversion rate, and the necessary deep sea water required for oyster breeding. Is defined as the amount of flow, that is, the amount of pouring. In general, the amount of deep ocean water to be poured in long-term animal husbandry is 1.0 to 5.0 times a day, that is, 1.0 to 5 times the amount of deep ocean water corresponding to the volume of the tank used. It is preferable to use a rotation amount of 0.0. In addition, in the point of zero rotation, that is, even if there is no inflow of seawater, oysters will absorb water for a limited time, it will not affect the animal husbandry itself, but considering the contamination of the aquarium, It is preferable to secure an inflow amount enough to discharge the contamination. That is, the amount of pouring is preferably 1.0 times or more, and preferably 5.0 times or less in terms of animal husbandry efficiency.
Moreover, when raising the temperature of marine water as mentioned above and performing animal husbandry by two processes, in the "highly nutritive animal husbandry process", the amount of 2.0 to 5.0 times per day, ie, 2.0 It is preferable to use an amount of ~ 5.0 rotation, and more preferably 2.5 to 3.0 times, that is, an amount of 2.5 to 3.0 rotation. Moreover, in the “freshness-preserving livestock raising process”, it is preferably 1.0 to 5.0 times or less per day, that is, 1.0 to 5.0 or less, and 1.0 to 3.0. It is more preferable that the amount is not more than double, that is, not more than 1.0 to 3.0.
If the supply of deep ocean water is within this range, a stable amount of deep ocean water is supplied, oysters are always abundant in mineral components, and viruses and bacteria discharged by oysters may be taken into other oysters again. It is possible to maintain a good water environment with no stress on oysters, while maintaining long-term breeding with little cleanliness and eutrophication.

It is preferable that the animal husbandry used in the present invention is performed in two steps, as described above, the “highly nutrientized animal raising process” and the subsequent “freshness keeping animal raising process”.
In other words, the “highly nutritive livestock farming process” achieves a high nutritional value by absorbing minerals into oysters. In this case, using slaughtering conditions where oysters are active, that is, using high-temperature deep ocean water. It is preferable to enhance the circulation of deep ocean water, whereby minerals in the deep ocean water are taken into the oyster, and bacteria and viruses in the oyster body are discharged and purified by the circulation in the deep ocean water.
On the other hand, oysters whose mineral content and the like have been absorbed to some extent by the “highly-nutrition livestock raising process” and whose nutritional value has been increased are subjected to the “freshness keeping livestock raising process” in that state, and the freshness is maintained. In this “freshness-preserving livestock raising process”, it is preferable to keep the oysters in a state in which the activity of oysters is reduced, and the livestock is cultivated using low-temperature deep seawater with a small amount of flowing deep seawater.
In addition, oysters whose mineral content has been absorbed to some extent by the “Highly Nutrient Animal Breeding Process” and whose nutritional value has been increased will retain their nutritional value in the next “Freshness Breeding Process”, but the freshness preserved livestock process The nutritional value is gradually decreased as the breeding period of the animal grows. However, the nutritional value is maintained for about 12 months from the start of the breeding, and the nutritional value is high and the freshness is maintained in the storage period of 6 months. You can get oysters.

  In such a preservation method, the “highly-nutrition-raising process” that is initially performed is about 10 days. Absorption of minerals into oysters is recognized and the nutrition becomes high-nutrition. preferable. Moreover, although absorption of minerals and purification of viruses and bacteria are gradually achieved from starting livestock raising, although it is preferable to carry out livestock raising for 2-3 days, In order to absorb minerals by oysters, it is considered necessary to cultivate a period somewhat longer than this purification period. Therefore, the “highly nurturing and raising process” should be performed for a period of about 4 to 10 days. preferable. Needless to say, this period can be changed according to market conditions. Next, a “freshness-keeping livestock raising process” is performed. In the freshness-keeping livestock raising process, since high nutritional value and freshness are maintained, oysters are stored according to the market conditions. Therefore, generally, it is preferable that the breeding period in the freshness keeping breeding process is about 10 days to 6 months.

  In addition, according to the storage period required, the storage method of the present invention is performed by combining the “highly nutritive livestock raising process” and the “freshness-preserving livestock raising process” or using these processes alone. You can also. Moreover, in the animal husbandry for preservation, the animal can be cultivated using animal husbandry conditions such as a combination of these “highly nutritive animal husbandry process” and “freshness keeping animal husbandry process”. It is not necessary to go through, and, for example, it is also possible to raise animals by increasing the amount of pouring using low-temperature deep seawater from the beginning.

Moreover, as a ratio which the oysters thrown into the water tank account, it is preferable that it is about 40-80 volume%, and it is more preferable that it is about 50-60 volume%. Within this range, a sufficient amount of deep ocean water can be supplied to oysters, and it is also preferable in terms of productivity and handling.
For example, when a 3t water tank is used, it is usually preferable to feed animals by introducing about 2,000 to 10,000 oysters. The smaller the percentage of oysters in the aquarium, the more oysters can take in oxygen and protect themselves from contaminants discharged from the oysters. However, considering productivity and operability, the above range is used. It is preferable. On the other hand, if the proportion of oysters in the aquarium is too large compared to the amount of water, the efficiency of purification and nutrition improvement tends to decrease, and in order to avoid this, it is necessary to increase the amount of pouring. Yes, it may be necessary to adjust the conversion rate for the aquarium.

  In order to secure the concentration of organic matter such as feces and dissolved oxygen, it is necessary to supply fresh deep ocean water as an amount that does not impede the amount of seawater in the oyster itself. However, it is necessary to supply a sufficient amount of deep ocean water.

During the long-term breeding period, both feeding and non-feeding are possible, but feeding according to the period is more preferable. In that case, since feeding may increase bacteria and the number of bacteria in seawater may increase, it is more preferable to feed aseptic algae or before shipping after long-term feeding.

Next, the present invention will be described in more detail based on experimental results.
First, as an experiment 1, an effective long-term preservation method for keeping oysters fresh is examined using clean and rich eutrophied water that does not contain pathogenic viruses and bacteria.
Animal husbandry is low-temperature deep ocean water (low-temperature deep ocean water that uses raw raw water as it is), heated deeper ocean water (heated ocean deep water), and UV sterilization. It was performed using the treated surface water (ultraviolet sterilized surface water), and evaluated for freshness and nutritional value before raising and after raising for a specific period. About freshness, while measuring about the period of livestock rearing, and 1 month of livestock rearing, and 2 months of livestock rearing, it measured about the thing before livestock rearing and after 10 days of livestock rearing, respectively.
In this measurement, freshness is determined by determining the amount of dehydrogenase in oysters by determining the amount of triphenyltetrazolium formazan (TF) produced, and dehydration involved in biological redox processes that are important as oyster energy acquisition means. The freshness of oysters was evaluated by the amount of enzyme. Specifically, a sample is prepared using oyster elaborates, and the amount of color development based on the generation of TF is quantified. The greater the amount of TF generated, the higher the freshness.
Moreover, evaluation of the nutritional value was performed by measuring the amount of minerals contained in oysters for each of the seven types of minerals. The higher the mineral content, the higher the nutritional value.

A specific experiment was performed as follows.
(1) Experiment 1: Setting of storage conditions by long-term livestock breeding (a) A 3-ton tank is poured with low-temperature deep ocean water and warm deep ocean water by 2.5 revolutions per day. 10,000 oysters were introduced each.
(I) Surface water treated with UV sterilization was poured into an 8-ton water tank at a rate of 2.5 rotations per day, and 20,000 oysters were put into the water tank.
Moreover, the preservation | save method by the long-term livestock raising of the mineral component holding | maintenance of an oyster, or raise was performed by the same condition setting. (See Table 1)

(A) Long-term animal husbandry experiments with low-temperature deep ocean water and warm deep ocean water Two types of oysters from Iwate Prefecture (Magaki from Kamaishi Bay, Iwate Prefecture and Otsuchi Bay, Iwate Prefecture, respectively, “Kamaishi” and “ Ten thousand pieces (referred to as “Oiso”) were put in a basket of 100 pieces each, submerged in a water tank, and used for pouring.
(B) Long-term animal breeding experiment with surface water treated with UV sterilization Two thousand kinds of oysters (Oiso and Kamaishi) from Iwate Prefecture were put in a basket of 100 each, submerged in a water tank, and used for pouring.
Thereafter, the oysters after the predetermined breeding period were evaluated together with the oysters before breeding. In addition, the oyster before raising was conducted as a comparative experiment.
The TF production amount test to check the freshness was conducted at the request of the Miyagi Public Health Association, which is a food registration and inspection organization certified by the Ministry of Health, Labor and Welfare. Mineral component analysis was performed by the National University Corporation Tohoku University Graduate School of Agriculture, Department of Nutrition.
Since the TF production amount test requires 5 g of oysters, it was obtained using 5 oysters, and seven types of mineral component analysis related to the nutritional value were calculated as average values from the measurement results of the content of 6 oysters.

Regarding the maintenance of freshness, that is, the result of the amount of TF produced is shown in FIG. 1, and the result of measurement of the content of each mineral component as an evaluation of the nutritional value is shown in FIG.
In FIG. 1, “warming DSW” and “low temperature DSW” indicate cases where the animals were cultivated using warmed deep ocean water and low temperature oceanic deep water, respectively, and “SW” was cultivated using ultraviolet sterilized surface water. Shows the case. In addition, “Oiso” and “Kamaishi” in FIG. 1 indicate the types of oysters cultivated respectively.
Also in FIG. 2, similarly, “warming DSW”, “low temperature DSW” and “SW” are the cases where the animal is bred using warming deep sea water, low temperature deep sea water and ultraviolet sterilized surface water, respectively. Each mineral component is shown for (a) sodium, (b) potassium, (c) calcium, (d) magnesium, (e) iron, (f) zinc, and (g) copper.

From these experiments, the following could be confirmed.
(A) Freshness by TF production amount test 1) In the maintenance of freshness in long-term livestock farming for 2 months or longer, the amount of TF produced is higher in the case of using deep ocean water than in the case of using ultraviolet sterilized surface water. It can be seen that the use of water is more effective in maintaining freshness than the case of using ultraviolet sterilized surface water.
2) Also, regarding the temperature of seawater in animal husbandry, when deep ocean water is cold, it can be seen that the amount of TF produced is greater than that before animal husbandry and the freshness is improved after one month. However, in the case of high-temperature warming deep sea water, it can be seen that the amount of TF produced is lower than that before breeding. This tendency shows the same tendency when the animal is bred at 13 to 16 ° C. using the UV sterilized surface water at the same temperature as that of the heated deep sea water. In order to maintain the freshness, It turns out that it is effective, so that it is low. In other words, it can be seen that it is preferable that the activity of oysters is reduced and the so-called dormant state is maintained for maintaining freshness.
(I) Mineral component analysis 1) In all mineral components, deep sea water exceeds that of surface water. Mineral components that are eutrophic of deep sea water are absorbed into the oyster body by circulation in the seawater. It was found that the oyster itself contributes to improving the mineral content.
2) It was found that the total component amount of warming deep ocean water exceeded that of low-temperature deep ocean water, and the seawater temperature was preferably 10 ° C to 20 ° C, more preferably 13 ° C to 16 ° C. From this, it can be seen that it is preferable to carry out warming deep sea water for nutrition. In addition, performing livestock cultivation with warmed ocean water in this way means that the circulation of ocean water for oysters is activated, as can be seen from the increase in mineral content in oysters. It can be seen that the purification of viruses and bacteria is also promoted.
3) Furthermore, regarding nutrition enhancement, it can be seen that sufficient nutrition can already be achieved by raising animals for 10 days. It has also been confirmed that purification has been achieved within this period.
(C) Summarizing the above results, in the preservation method of the present invention, at the start of the breeding, the animal is bred with warmed deep sea water, and then the temperature is changed to low-temperature deep sea water with the passage of time. Immediately after the start of animal breeding, oysters are activated to absorb a large amount of mineral components and are purified as necessary. It has been found that it is preferable to be in a dormant state such that stagnation occurs. In addition, it turns out that it is enough if it raises for 10 days with the deep sea water heated at the time of the start of animal breeding.
However, this breeding period is also affected by the temperature of the deep sea water, and if the deep sea water is cold, it can be understood that the same result of high nutrition can be obtained by setting the long breeding period. .

(2) Experiment 2: Implementation of salt concentration and salt equivalent analysis Next, as for the salinity concentration of oysters, as in Experiment 1, using low-temperature deep sea water, warm deep sea water, and ultraviolet sterilized surface water, animal husbandry 1 For two kinds of oysters (Otsuchi and Kamaishi) that were bred for two months and two months, measurements of salt concentration salt equivalents were carried out. The number of specimens is 10 in any case.
In addition, the measurement of salt concentration salt equivalent amount was carried out by requesting the Miyagi Public Health Association. The results are shown in FIG. In FIG. 3, as in FIG. 1, “warming DSW”, “low temperature DSW” and “SW” were bred using warmed deep ocean water, cryogenic ocean deep water and ultraviolet sterilized surface water, respectively. “Oiso” and “Kamaishi” indicate the types of oysters bred respectively.

From the results shown in FIG. 3, it can be seen that, in the case of preservation by long-term animal husbandry, the amount of salt contained in oysters increases in proportion to the animal husbandry period when deep sea water is used. In addition, the result of the salt equivalent of 1.0-1.2g / 100g of oysters cultivated in deep ocean water for 2 months is from other fishery products from the Ministry of Education, Culture, Sports, Science and Technology's “Fiveth Amendment Japanese Food Standard Composition Table”. It can be seen from the results in Table 2 below that there is no significant difference and moderate saltiness.

(3) From the above experimental results, the following can be said.
1) As a result of conducting experiments on long-term animal husbandry using deep ocean water compared to the case of using surface water that has been subjected to ultraviolet sterilization, deep ocean water is more It can maintain or improve freshness and mineral components.
2) Cleanliness of deep ocean water and low-temperature stability provide the advantage of maintaining the freshness of oysters, and eutrophication provides the advantage of intake of mineral components into the oyster body, resulting in fresh and nutritious oysters. It has been found that it can be provided.

Moreover, by the preservation method of the present invention, the appearance of seasonal oysters (a) landed in March before breeding and oysters (b) bred for 5 months using deep sea water from May (September FIG. 4 shows a photograph showing “photographed in FIG.
According to these photographs, the oysters stored for a long time according to the present invention show no significant deterioration in the appearance and the elasticity of the scallops compared to the oysters landed in March, which are seasonal oysters. It can be seen that the gloss and the pigment and state of the mantle are unchanged. In addition, when these oysters were actually eaten, the ones bred with deep sea water maintained the same taste, or exceeded that of seasonal oysters. Has gained reputation.

  Since the present invention is an extremely safe, fresh and nutritious oyster made by using deep-sea water with high cleanliness and rich in inorganic nutrients, the oyster end-of-season is similar to the peak season. Distribution of high-value-added oysters that are in good condition, fresh and nutritious is possible. Moreover, safer oysters that can reduce the risk of oyster norovirus contamination, which is becoming more serious every year, can be distributed and can be applied not only to the oyster industry but also to other aquaculture and animal husbandry. It promotes effective use of deep ocean water.

Claims (3)

A method for preserving oysters by using deep ocean water, setting the temperature of the ocean water at 0 to 20 ° C., and pouring the oysters over 4 days to 6 months,
A method for preserving oysters, wherein the initial deep sea water temperature is 10 to 20 ° C., and then the fresh sea water temperature is set to 0 to 9 ° C. The method for preserving oysters according to claim 1 , wherein the amount of flowing deep sea water is an amount of 1.0 to 5.0 rotations per day of the deep sea water corresponding to the volume of the aquarium. The method for preserving oysters according to claim 1 or 2 , wherein the period of raising the seawater at a seawater temperature of 10 to 20 ° C is 4 to 10 days.