Method for easily separating out fish flesh

Abstract

The present invention relates to a method for quickly and cleanly separating fish flesh from fish bones by separating out the fish flesh after heating the fish at a temperature and for a duration that softens the fish flesh while maintaining the strength of the fish bones. In the method for separating out fish flesh, according to the present invention, fish flesh is softened with heat while the strength of the fish bones is maintained, and then the fish flesh is separated out so that the fish flesh can be separated from the bones quickly and cleanly, and thus the manpower and time required to debone fish flesh are reduced, the fish flesh collected from fish is high in yield, and fish flesh with excellent flavor can be obtained by removing the fishy smell of the fish.

Description

How to easily separate fish fillets

[0001] The present invention relates to a method for quickly and cleanly separating fish flesh from bones and bones of fish by heating the fish at a temperature and for a period of time at which the fish flesh becomes soft while the fish bones maintain their strength, and then separating the fish flesh.

[0002] Recently, our society has been changing from a meat-centered consumption culture to a vegetarian and seafood-centered consumption culture. Aquatic products such as fish are preferred by consumers because they are rich in essential amino acids and essential fatty acids and are high in protein content, making them nutritionally superior and relatively inexpensive.

[0003] Fish is not only an important source of animal protein, but is also rich in unsaturated fatty acids and minerals, making it effective in preventing and treating chronic diseases such as heart disease, high blood pressure, and cancer, and thus attracting much attention as a health food. Accordingly, the tendency to obtain nutrients from fish rather than from beef, pork, etc. is increasing, and fish consumption is steadily increasing.

[0004] In recent years, with the highly developed food processing technology, only the edible parts of fish are separated and processed into fish meat, which is widely used as a raw material for various foods. The edible parts of fish are about 30-70%, excluding inedible parts such as the head, tail, bones, fins, and internal organs, and in most cases, around 50% is considered to be edible.

[0005] The edible part of fish, the fish flesh, has been separated by hand using a knife, but this is not only time-consuming and labor-intensive, but also difficult to separate from smaller fish, although it is possible to do so for larger fish. In addition, the fish can be ground with the bones, but this is limited to small fish or fish with weak bones, and its usability is also limited.

[0006] For example, Korean Patent Publication No. 1401461 discloses a method of pretreating fish meat by heating it to a core temperature of 40 to 45°C for 10 to 20 minutes, then cooling it to 10°C or lower, and then cutting the pretreated fish meat into small pieces and mixing it with tenderized meat to grind the meat.

[0007] The above invention maintains the unique flavor of fish meat through a preprocessing operation, and enables fish cakes manufactured using the same to have the unique flavor of fish meat while having physical properties similar to those of conventional fish cakes.

[0008] In addition, Korean Patent Publication No. 1808486 discloses a method for thawing frozen fish in a refrigerator at -3 to 10°C within 24 hours so that the body temperature of the fish reaches -2 to -3°C, then cutting off the head of the thawed fish, standing it upright with the tail facing upward, then cutting the dorsal fin of the fish vertically from the tail toward the cut head so that the bone line of the fish is exposed, then tilting the tail in a direction of 65 to 75°, making a first incision of a predetermined length along the bone line of the tail, and then making a second vertical incision along the bone line of the vertically erected body to cut the fish in half in the center, and then removing by-products such as internal organs, eggs, and snails from the body of the fish that has been split in half, and then removing bones and bones, and then peeling and removing the skin to secure a fish fillet.

[0009] The above fish processing process is done by naturally defrosting the fish in a defrosting room without using water, preventing moisture from penetrating the fish, and maximizing yield through vertical processing. It also provides the effect of maintaining elasticity, freshness, and the unique juices and flavor of the fish by making the work easier and shortening the work time.

[0010] In addition, Korean Patent Publication No. 2125061 discloses a method of obtaining squid by heating squid that has been pretreated to 50 to 150°C and then placing it in a first separating screen, and having a crushing blade provided on the upper side of the first separating screen, and having the crushing blade inclined to the first separating screen and rotating while applying pressure to the squid downwards so that the squid meat is filtered to the lower part of the first separating screen, and then sieving the squid meat again in a second separating screen.

[0011] The above method has the advantage of minimizing the fishy smell through a pretreatment process, easily crushing the fish by passing it through a strainer multiple times, and easily separating the fish meat from the crushed fish.

[0012] The above methods are used to pre-treat fish meat before separating it, thereby preserving the unique flavor of the fish meat or minimizing the fishy smell, and when processed foods are made using the fish meat, the unique juice and flavor of the fish can be displayed.

[0013] As mentioned above, conventional methods focus on improving the quality of separated fish meat or making it easy to separate fish meat, but in order to improve the quality of fish meat, a lot of time and manpower are required to separate fish meat, and when the fish meat and bones are ground together to shorten the separation process, the fish meat and bones are mixed and some bones are included, which limits the use of fish meat, and it has the disadvantage of being limited to small fish species.

[0014] The present invention provides a method for easily separating and collecting fish flesh without mixing in bones and bones and while maintaining the unique flavor of the fish flesh, and develops a process that can automate the separation of fish flesh by replacing manpower.

[0015] In order to solve the above problem, the present invention provides a method for separating fish flesh, comprising the steps of: washing fish with water to remove foreign substances; heating the washed fish at 45 to 49°C for 15 to 45 minutes; separating fish flesh from fish bones of the heated fish; and removing foreign substances including fish skin from the separated fish flesh.

[0016] At this time, the step of removing the foreign substance is to disembowel the fish, remove the gills and internal organs, and wash it with water. The step of heating is preferably to immerse the washed fish in carbonated water having a pH of 4 to 5 at a temperature of 10°C or lower for 30 to 60 minutes, then take it out and heat it. It is more preferable to add refined salt to the carbonated water before taking out the fish immersed in the carbonated water.

[0017] In addition, the heating step is preferably performed by heating the fish washed in water at 45-49°C for 35-45 minutes, or by disemboweling the fish to remove the gills and internal organs and then washing the fish in water at 45-49°C for 15-25 minutes.

[0018] In addition, it is preferable to steam the fish with steam generated by heating water under a reduced pressure of 72 to 113 mmHg (abs), and it is more preferable to release the reduced pressure state momentarily after the reduced pressure heating.

[0019] Additionally, it is preferable that the water used to wash the fish be alkaline ionized water.

[0020] The method for separating fish flesh according to the present invention heats the fish flesh to soften it while maintaining the strength of the fish bones and then separates the fish flesh, so that the fish flesh can be quickly and cleanly separated from the bones and bones, thereby reducing the manpower and time required for removing the fish flesh.

[0021] In addition, the yield of collecting fish meat from fish is high, and the fishy smell of the fish is removed, so fish meat with excellent flavor can be obtained.

[0022] The present invention relates to a method for easily separating fish flesh by heating the fish flesh at a temperature and for a period of time at which the fish flesh becomes soft and the fish bones and bones maintain their strength. This method can reduce the manpower and time required for separating the fish flesh by quickly and cleanly separating the fish flesh from the bones and bones, and further provides a process for automating the separation of the fish flesh by replacing manpower.

[0023] In the past, fish flesh was separated manually by using a knife to cut the fish fillet, but this method was not economical because it required a lot of time and manpower, and it was difficult to apply it to fish that were damaged or small in size and therefore had low marketability.

[0024] Unlike meat, fish meat has a loose protein structure, making it easy for the tissue to be destroyed even when heated at a low temperature. The present invention utilizes the characteristics of fish meat protein to easily separate fish meat using thermal properties rather than the conventional mechanical method.

[0025] As a method of easily separating only the flesh from fish, the fish is washed thoroughly with water, heated at a low temperature to soften the fish flesh, and then the fish flesh is separated from the bones. Before washing, the fish is disemboweled to remove the gills and intestines, and then washed with water to remove any blood clots. This reduces the inclusion of foreign substances such as intestines in the separated fish flesh.

[0026] In order to make it easy to separate the fish flesh from the fish bones, it is advisable to soak the washed fish in carbonated water before heating it and then take it out.

[0027] Fish bones (and bones) contain a lot of calcium and phosphorus, and exist mainly in the form of calcium phosphate. Calcium phosphate does not dissolve in water, but it is slightly soluble in water containing carbon dioxide. Therefore, when fish is soaked in carbonated water, some of the fish bones dissolve, weakening the bond between the fish bones and fish meat. When the fish is heated, the fish meat can easily separate from the fish bones.

[0028] When a fish is disemboweled to remove the gills and internal organs, the exposed fish bones inside the fish's stomach come into direct contact with the carbonated water and dissolve, making it easier to separate the fish meat from the bones.

[0029] Carbonated water is an aqueous solution of carbon dioxide, and the carbon dioxide saturation of carbonated water increases as the temperature decreases. Therefore, it is desirable to keep the temperature of the carbonated water below 10°C, preferably 1 to 5°C, while soaking the fish for 30 to 60 minutes. In addition, carbonated water removes the fishy smell of the fish, so it also has the effect of improving the flavor of the separated fish meat.

[0030] When a fish dies, it is initially flexible, but after a certain period of time, rigor mortis occurs, causing the muscle tissue to harden. After that, it softens again through autodigestion and begins to decay. In order to easily separate the fish flesh, it is advisable to heat the fish at the point where it softens after hardening.

[0031] Normally, the pH of fish flesh is around 7.0 to 7.5 immediately after death, and when rigor mortis begins, lactic acid is produced and accumulated, lowering the pH. After reaching the lowest point at complete rigor, the pH rises and decay begins. The pH of decayed fish is around 6.2 to 6.4 for red-fleshed fish and 6.7 to 6.9 for white-fleshed fish.

[0032] Autodigestion of fish occurs through cathepsin, a protein hydrolyzing enzyme present in fish muscles, and the optimal pH for cathepsin is around 4.5. Therefore, if the pH of the carbonated water is adjusted to 4-5, autodigestion of fish is promoted, and the tissue of fish that has undergone autodigestion becomes soft and can be easily separated from the fish bones.

[0033] Amino acids and low-molecular nitrogen compounds produced by the autodigestion of fish promote the growth and proliferation of spoilage bacteria, and when autodigestion is complete, the pH rises, creating an environment suitable for bacterial growth, making it easy for spoilage to occur. However, carbonated water has an acidic pH of 4-5, and the carbon dioxide produced from carbonated water has a sterilizing effect, so it can suppress spoilage that follows autodigestion.

[0034] In addition, during the rigor mortis process, adenosine triphosphate (ATP), the muscle energy of fish, is broken down to produce inosinic acid, and inosinic acid enhances the savory flavor of fish flesh. Therefore, if the fish flesh is separated during the autodigestion process after rigor mortis, the flavor of the fish flesh can be enhanced.

[0035] To make it easier to separate the fish flesh, it is recommended to add salt to the carbonated water before taking out the fish that has been soaked in it.

[0036] Carbonated water is a state in which carbon dioxide is dissolved in water in an unstable state. When salt is added, carbon dioxide bubbles are created around the salt particles, and the surfaces of the carbon dioxide bubbles dissolve in the water and are released out of the water. Carbon dioxide bubbles are created again around the salt particles from which the carbon dioxide bubbles were removed and are released out of the water. This process is repeated, and this process occurs very quickly, causing the carbonated water to bubble violently until the carbon dioxide is consumed.

[0037] The above carbon dioxide bubbles supply carbon dioxide while pressurizing the fish, which promotes the dissolution of the fish bones, allowing the fish bones and fish meat to be separated more easily.

[0038] Due to water pollution, heavy metal contamination of fish is getting worse, and there is a concern that heavy metals will accumulate in the human body when consuming it, causing fatal harm, so it is necessary to remove heavy metals from fish. Salt has the property of absorbing heavy metals, so when salt is added to carbonated water containing fish, the salt absorbs the heavy metals contained in the fish, and when the fish is taken out of the carbonated water with salt added, the heavy metals are removed from the fish along with the salt.

[0039] At this time, it is preferable to use refined salt as the above salt, and salt produced from seawater has a weakened ability to absorb heavy metals from polluted seawater, but refined salt has its ability to absorb heavy metals restored by removing impurities and heavy metals with an ion resin membrane, so it can absorb and remove more heavy metals from fish.

[0040] In addition, refined salt has a finer particle size than sea salt, so even when the same amount is used, the rate at which carbon dioxide bubbles are generated around the particles is faster than that of sea salt, so the effect of separating fish bones and fish meat is high.

[0041] The above washed fish is heated at 45-49℃ for 15-45 minutes to soften the fish flesh while maintaining the strength of the fish bones and bones. When the fish flesh is separated in this state, the fish flesh is easily separated from the fish bones (and bones).

[0042] If we break down the settings of the heating temperature and time a little more, when removing the gills and internal organs by disemboweling the fish and removing the blood clots while washing it with water, it is recommended to heat it briefly at a low temperature of 45-49℃ for 15-25 minutes, and when heating the fish as is without disemboweling, it is recommended to heat it for a long time at a low temperature of 45-49℃ for 35-45 minutes.

[0043] The above heating temperature and time are in the range to ensure that the fish is not heated above 50°C during heating and that the fish's core temperature reaches 43±1°C at the end of heating. If the fish is heated above 50°C, the fish bones, bones, tail, etc. fall off during the subsequent fish meat separation process, making it difficult to quickly and cleanly separate the fish meat from the bones and bones.

[0044] When the heating is stopped when the fish's core temperature reaches 43±1℃, the fish meat becomes optimally separated from the fish bones due to the characteristics of fish protein, which is composed of visceral protein and matrix protein.

[0045] If the heating temperature and time are below the above, the fish meat is not sufficiently softened, so the fish bones and fish meat are not separated well. If the above range is exceeded, the fish bones and fins become weak, causing bones to become mixed in the fish meat and the fins to be damaged, resulting in the problem of the fins becoming mixed in the fish meat during the subsequent process of removing the fish skin from the fish meat.

[0046] In addition, the heating temperature and time need to be adjusted within the above range depending on the type and size of the fish. The larger or firmer the fish, the higher the heating temperature and time. The smaller or softer the fish, the lower the heating temperature and time. In addition, the higher the heating temperature, the lower the heating time. In this way, the strength of the bones is maintained as much as possible depending on the type and condition of the fish, while the fish flesh is made as soft as possible.

[0047] The heating method is not particularly limited, but can be steamed, heated with hot air, or immersed in hot water. In order to easily perform the next step of separating the fish flesh, it is preferable to heat the fish by hanging it with the head facing up and the tail facing down by hooking the lower jaw of the fish's snout or tying it with a string.

[0048] When the fish is heated, the snout part becomes weaker as it cooks, so the lower jaw of the fish cannot support the weight of the fish and is likely to come off the hook or string. Therefore, when immersing in hot water, it is recommended to heat the fish with the snout part above the water surface, and when steaming or heating with hot air, it is recommended to hook the fish with a hook or tie it with a string around the gill cover.

[0049] Water vaporizes into steam at 100℃ under atmospheric pressure, but vaporizes below 100℃ when the pressure is reduced. Therefore, when water is heated in a vacuum environment of 72~113 mmHg(abs), steam of 45~54℃ is generated, which can heat fish. When fish is heated under reduced pressure, the bond between fish tissues is weakened, allowing the fish meat to be separated from the bones more easily.

[0050] In order to further promote the separation of fish flesh, it is desirable to release the depressurization state momentarily after depressurization heating. When the depressurization state is released momentarily, the outside air rushes into the depressurization heating device at once, applying a mechanical shock to the heated fish, and the inside of the depressurization heating device becomes pressurized momentarily. Then, the air escapes from the inside where the pressure is increased to the outside where the pressure is atmospheric, and the inside of the depressurization heating device becomes atmospheric pressure.

[0051] This phenomenon occurs instantaneously, and during this process, the steamed fish is shocked by a sudden change in pressure, so that the fish meat flows away from the bones and is naturally separated, or the next process of separating the fish meat can proceed easily.

[0052] It is preferable that the above heating temperature be based on the fish's core temperature, but when the fish is heated, heat is transferred from the surface to the core by conduction. Depending on the type and size of the fish, there are thick and thin types of flesh, so even when heated to the same temperature, the core temperature of each fish is different, and it is not easy to measure the core temperature of each fish during heating.

[0053] Therefore, since it is inefficient to classify the same type of fish into similar thicknesses and then heat each classified fish individually, it is appropriate in terms of work efficiency to base the heating temperature on the surface temperature of the fish.

[0054] However, if the surface temperature of the fish is used as the standard for heating, the internal temperature will differ depending on the thickness of the fish, which will result in differences in the degree of tenderness of the fish flesh, and as a result, the degree of separation of the fish flesh after heating will differ for each fish, which has the disadvantage of causing differences in the degree of tenderness of the fish flesh for each fish.

[0055] Using a microwave generator such as a microwave oven, the surface and the deep part can be heated simultaneously. However, although heating using microwaves can control the heating time, it is difficult to control the heating temperature as mentioned above.

[0056] To solve this problem, it is desirable to use ionized alkaline water as the water for washing the fish.

[0057] Alkaline ionized water is water obtained by placing positive and negative electrodes in water and applying direct current. On the positive electrode side, negative ions dissolved in water gather to create acidic ionized water, and on the negative electrode side, positive ions gather to create alkaline ionized water.

[0058] Hydrogen ions (H) in water + ) obtains electrons from the cathode and generates active hydrogen, so alkaline ionized water is rich in active hydrogen, and active hydrogen is in an activated state, so it is highly reactive and reacts with metal elements such as potassium, calcium, magnesium, and zinc contained in fish flesh, releasing a lot of heat and returning to a molecular state.

[0059] Metal elements are evenly distributed inside the fish flesh, and hydrogen has the smallest particle size of all elements after helium, so it easily penetrates into the fish flesh. Therefore, when fish washed with alkaline ionized water is heated, the surface of the fish is heated by the heat source and the core of the fish is heated by the active hydrogen at the same time, so the inside and outside of the fish are evenly heated.

[0060] Additionally, alkaline ionized water prevents discoloration of fish and maintains freshness, and active hydrogen has the effect of removing fishy smell, which can also improve the flavor of fish meat.

[0061] When immersing fish in carbonated water, it is recommended to remove the fish from the carbonated water and then wash it with alkaline ionized water. In this case, the fish is heated while containing the alkaline ionized water, so the surface and the core of the fish can be evenly heated.

[0062] The process of separating fish fillets can be done manually by holding the fish head with your hand and pulling the fish fillets from top to bottom, or by mechanical means such as an airbrush or ultrasonic waves. If the fish is hung during the previous heating process, the process of separating the fish fillets can be done more easily.

[0063] Fish bones are generally classified into the vertebrae that run through the middle of the body, the ribs that surround the internal organs, the fin spines, and the small spines that are embedded in the fish flesh. Since the fish is connected as one from the mouth of the fish along the vertebrae to the tail, and the ribs are attached to the vertebrae, the fish flesh and the fish bones can be easily separated by heating at the above-mentioned temperature and for the time that does not weaken the fish ribs.

[0064] In addition, since the ribs of a fish are connected obliquely from the head to the tail along the spine, if you sweep the fish flesh from top to bottom as described above, that is, from the head to the tail, you can separate the fish flesh while maintaining the original shape of the fish bones, allowing you to cleanly separate the fish flesh from the fish bones.

[0065] Separated fish meat contains fish skin and fins, and the fins have bones attached to them. Some fish bones may be included during the process of separating fish meat. Therefore, the separated fish meat is filtered through a sieve, net, mesh, filter, etc., or these are removed using a rake, etc.

[0066] The thorns attached to the fins do not separate from each other during the above heating temperature and time, so the fish skin, fins, and thorns remain attached to each other, and the fish meat softens due to heating and separates from the fish skin. Therefore, when the fish skin is removed from the separated fish meat, the fins and fin bones can be removed at once, and in this process, the thorns embedded in the fish meat and the fish bones included in the process of separating the fish meat can also be removed.

[0067] Also, since the intestines of the fish are wrapped inside the ribs, when you scrape off the fish meat attached to the fish bones outside the ribs, the intestines inside the ribs are rarely included in the separated fish meat. Depending on the structure of the ribs depending on the type of fish, if a lot of intestines are included in the fish meat during the separation process or if the inclusion of intestines greatly affects the flavor of the fish meat, it is advisable to remove the intestines before heating the fish.

[0068] The fishy smell of fish is concentrated in the fish skin, so fish meat with foreign substances such as skin, fins, bones, and small bones removed has excellent flavor. By mixing a gelling agent such as agar into the fish meat, it can be made into a grilled fish block, or various ingredients or seasonings can be added, shaped into an appropriate size, and then heated to process it into fish cakes or protein bars.

[0069] Hereinafter, the present invention will be described in more detail based on the following examples and test examples.

[0070] However, the following examples are only for illustrating the present invention, and the present invention is not limited to the following examples, and it will be apparent to a person having ordinary skill in the art to which the present invention pertains that the present invention can be changed to other equivalent examples and substituted within the scope that does not depart from the technical spirit of the present invention.

[0071]

[0072] <Example 1>

[0073] After preparing 10 adult fish each of mackerel, salmon, and flounder, the belly of each fish was disemboweled to remove the gills and internal organs, washed with water to remove any blood clots, and incisions were made to the minimum extent necessary for removing the internal organs while being careful not to break the spines during disembowelment.

[0074] A constant-temperature water bath installed in the workroom was filled with water and set to 40°C, and when the water temperature reached 40°C, the lower jaw of the snout of the prepared fish was hooked and the fish was immersed for 10 minutes with the snout above the water surface of the constant-temperature water bath.

[0075] The fish immersed in the constant temperature water tank were taken out and placed on the upper part of the storage container. The fish flesh was gently rubbed from top to bottom by hand to separate the fish flesh into the storage container placed at the bottom. After collecting the separated fish flesh, it was sieved to remove the fish skin containing the fins and bones.

[0076] The same method was performed for constant temperature water bath temperatures of 45 ℃, 47 ℃, 49 ℃, 50 ℃, and 55 ℃ and heating times of 15 minutes, 20 minutes, 25 minutes, and 30 minutes, respectively, to obtain fish flesh with fins, bones, and fish skin removed.

[0077]

[0078] <Test Example 1> Measurement of fish meat separation efficiency according to heating time and temperature

[0079] In the above Example 1, the degree of separation of fish flesh and the presence of bones in the separated fish flesh were investigated.

[0080] There was no difference in the degree of separation and presence of bones depending on the species of mackerel, salmon, and flounder, and the results of measuring the separation efficiency according to heating time and temperature are shown in Table 1 below.

[0081]

[0082] Measurement results of separation efficiency of fish meatHeating time (min)1015202530Hot water temperature (℃)40××△※△※△▲45△▲○●○●○●○▲47△●○●○●○●○▲49△●○●○●○●○▲50○▲○▲○※○※○※55○▲○※○※○※○※- Degree of separation of fish meat and fish bones (bones): ○(well separated), △(some not separated), ×(mostly not separated)- Presence of bones in fish meat: ●(no bones), ▲(some), ※(many bones)

[0083]

[0084] Looking at Table 1 above, when heated to 40℃, the fish flesh did not separate well for up to 15 minutes, and when heated for 20 minutes, some of the fish flesh separated, but the fish flesh contained many bones.

[0085] When heated at 45℃ for 10 minutes, the heat was not well transmitted to the deep part, so some of the fish meat was not separated. When heated for more than 15 minutes, the heat was transmitted to the deep part, so the fish meat was well separated, and there were no bones in the fish meat. However, when heated for 30 minutes, the strength of the fish bones and bones weakened, so some bones were included in the fish meat.

[0086] At 47℃ and 49℃, some of the fish meat was not separated when heated for 10 minutes, but when heated for 15 minutes or more, the fish meat was separated well and no bones were included in the fish meat, and when heated for 30 minutes, some bones were included in the fish meat.

[0087] At 50℃, the fish flesh was well separated when heated for 10 minutes, but some bones were included. When heated for more than 20 minutes, the fish flesh contained many bones. When heated for more than 15 minutes at 55℃, the fish flesh contained many bones. At temperatures above 50℃, fish bones, bones, tails, etc. often fell off.

[0088] Looking at the above results, it can be seen that at 40℃, the fish meat is not separated well or is only partially separated, at 50℃ or higher, the fish meat is separated well but some or many bones are contained in the fish meat, and when heated at 45~49℃ for 15~25 minutes, the fish meat is separated well from the fish bones and the separated fish meat does not contain bones.

[0089]

[0090] <Example 2>

[0091] In the above Example 1, mackerel, which had been washed with water to remove blood clots, was immersed in carbonated water having a pH of 4.5 at a temperature of 3°C for 40 minutes, and then refined salt was sprinkled in an amount of 1 wt% of the carbonated water to generate bubbles. After the bubble generation was complete, the fish was taken out and heated in a constant-temperature water bath with warm water at 49°C for 20 minutes. In this manner, fish meat with fins, bones, and fish skin removed was obtained.

[0092]

[0093] <Example 3>

[0094] In the above Example 1, the mackerel, which had been washed with water to remove blood clots, was hung on a hanger in the workroom, the pressure in the workroom was reduced to 88 mmHg (abs), and the mackerel was heated for 20 minutes with 49°C steam generated by heating water instead of hot water in a constant-temperature water bath, and then the heating was stopped and the workroom door was opened at once to instantly make the pressure in the workroom normal pressure. In this case, fish meat with fins, bones, and fish skin removed was obtained in the same manner as in the above Example 1.

[0095]

[0096] <Example 4>

[0097] In the above Example 1, fish meat with fins, bones, and fish skin removed was obtained in the same manner as in the above Example 1, except that alkaline ionized water was used as a washing water to remove blood clots from mackerel with gills and internal organs removed, and the fish meat was heated in warm water at 49°C for 20 minutes.

[0098]

[0099] <Test Example 2> Measurement of fish meat collection rate and fishy odor

[0100] In the above Example 1, when mackerel was heated in hot water at 49°C for 20 minutes, and in Examples 2 to 4, the fish meat collection rate and the fishy smell of the collected fish meat were measured, and the results are shown in Table 2 below.

[0101] The fish meat collection rate was expressed as a percentage of the weight of the fish meat obtained compared to the weight of the fish before disembowelment, and the fishy smell was expressed by measuring the trimethylamine (TMA) content in the fish meat from which the fins, bones, and fish skin of the example had been removed and stored in a refrigerator at 4°C for 10 days.

[0102] Trimethylamine is almost non-existent immediately after the death of fish, but is produced through the reduction of trimethylamine oxide (TMAO) by the enzymatic action of postmortem bacteria. It acts as a causative agent of the fishy smell of seafood and is an indicator of freshness.

[0103] 10 g of mackerel fish meat of the example was placed in a homogenizer, 80 ml of 5% trichloroacetic acid (TCA) solution was added, homogenized for 1 minute, and the filtered filtrate was used as a sample.

[0104] 1 ml of a 1% boric acid solution was placed in the inner chamber of a Conway type diffusion unit, 1 ml of the above sample was placed in the outer chamber, 1 ml of a saturated potassium carbonate solution was quickly injected, and the lid was closed. The sample and potassium carbonate in the outer chamber were mixed well, and the unit was left in an incubator at 37°C for 2 hours. When the boric acid solution in the inner chamber turned green, it was titrated with a 0.02 N hydrochloric acid solution until it turned red.

[0105]

[0106] Fish meat collection rate and fishy odor measurement results Example 1 Example 2 Example 3 Example 4 Fish meat collection rate (%) 56.1 58.4 57.3 56.7 TMA content (mg%) 2.5 4 1.7 8 2.4 5 1.92

[0107]

[0108] As shown in Table 2 above, the fish flesh collection rate was the highest in Example 2, where the fish was immersed in carbonated water, and the next highest was in Example 3, where the fish was heated with steam under reduced pressure and then the reduced pressure was instantly released. It is believed that the carbonated water dissolved the calcium phosphate of the fish bones to promote the separation of the fish flesh, and the fish was heated under reduced pressure to weaken the bond between fish tissues and then the reduced pressure was instantly released to give the fish a rapid pressure change, thereby increasing the separation efficiency of the fish flesh.

[0109] Overall, there was no significant difference between each group, indicating that the fish flesh could be sufficiently separated from the fish bones when heated at 49°C for 20 minutes.

[0110] The TMA content was lowest in Example 2, where the fish was immersed in carbonated water, and next lowest in Example 4, where the fish was washed with alkaline ionized water. This is believed to be because the carbonated water removed the fishy smell of the fish, and the alkaline ionized water prevented the fish from discoloring, maintained freshness, and removed the fishy smell.

[0111] Normally, when the TMA content exceeds 4 mg%, it is judged to be in the early stages of spoilage, but since the results of the above test are all less than 4 mg%, it can be seen that if the fish is heated at a low temperature as in the example, the fish meat is quickly separated and collected, and then stored in the refrigerator, the fish meat does not spoil easily and can be stored and used for a long time.

[0112] As described above, it is believed that immersing fish in carbonated water and then heating it or heating the fish with steam under reduced pressure can separate the fish flesh more effectively, and pretreating the fish with carbonated water or alkaline ionized water before heating can reduce the fishy smell during storage.

[0113] The method for separating fish flesh of the present invention can quickly and cleanly separate fish flesh from bones and bones, thereby reducing the manpower and time required for removing fish flesh, increasing the yield of collecting fish flesh from fish, and automating the separation process of fish flesh by replacing manpower, so that it can be usefully utilized in the processed food industry using fish flesh.

Claims

1. Step of washing the fish with water to remove foreign substances; A step of heating the washed fish at 45 to 49°C for 15 to 45 minutes; A step of separating fish meat from the fish bones of the above heated fish; and A method for separating fish flesh, comprising: a step of removing foreign substances including fish skin from the separated fish flesh.

2. In claim 1, The step of removing the above foreign substances is to disembowel the fish, remove the gills and internal organs, and then wash it with water. The above heating step is a method for separating fish flesh, characterized in that the washed fish is immersed in carbonated water having a pH of 4 to 5 at a temperature of 10°C or lower for 30 to 60 minutes, then taken out and heated.

3. In claim 2, A method for separating fish flesh, characterized in that refined salt is added to carbonated water before removing the fish immersed in the carbonated water.

4. In claim 2, A method for separating fish flesh, characterized in that the heating step comprises heating the fish washed in water at 45 to 49°C for 35 to 45 minutes, or heating the fish washed in water after removing the gills and internal organs by disemboweling the fish and heating it at 45 to 49°C for 15 to 25 minutes.

5. In claim 1, The above heating is a method for separating fish flesh, characterized in that the fish is steamed with water vapor generated by heating water under a reduced pressure of 72 to 113 mmHg (abs).

6. In claim 5, A method for separating fish flesh, characterized in that the depressurization state is instantly released after the above-mentioned depressurized heating.

7. In claim 1, A method for separating fish flesh, characterized in that the water used to wash the fish is alkaline ionized water.