KR20160131555A

KR20160131555A - Method for processing frozen tuna for sliced raw tuna

Info

Publication number: KR20160131555A
Application number: KR1020150064255A
Authority: KR
Inventors: 복중한
Original assignee: 복중한
Priority date: 2015-05-08
Filing date: 2015-05-08
Publication date: 2016-11-16

Abstract

The present invention relates to a method for processing frozen tuna to prepare raw tuna slices, intended to increase physical properties and quality of raw tuna slices, by defrosting frozen tuna blocks in a saline solution having proper salinity and temperature, and then re-freezing the same thereafter. According to the present invention, the raw tuna slices produced by the method have excellent textures and tastes, thereby creating added value owing to high quality.

Description

METHOD FOR PROCESSING FROZEN TUNA FOR SLICED RAW TUNA [0002]

The present invention relates to a method for processing a frozen tuna for tuna fish, and more particularly, to a method for processing frozen tuna for tuna fish, in which a frozen tuna block is defrosted in saline at an appropriate salinity and temperature, The present invention relates to a processing method of tuna.

Tuna is a representative fish of the mackerel and is called tuna in Korea, tuna in Japan, and tuner in the United States. Tuna is a fish that lives only in the South Pacific and the Atlantic Ocean where pollution is the least on the earth. It is popular because its protein content is high but its fat content and calories are low. In addition, tuna is rich in DHA to improve memory, improve learning ability, cholesterol reduction, and is known to have excellent efficacy in preventing dementia.

Tuna is commonly used in canned or cauliflower form. Especially, tuna with high quality such as bluefin tuna are popular as sashimi. The tuna sashimi shows a considerable difference in texture and taste due to the processing of tuna, for example, thawing and maintenance, as well as the type and location of tuna.

Since the tuna used in tuna fish are usually frozen at -60 ° C to -50 ° C, it is essential to defrost the tuna fish in order to use it.

Saline defrosting, water defrosting, and natural defrosting are known for defrosting frozen tuna for use with tuna circuits. Most commonly, saline defrosting is used, in which salt is added to water at about 28 ° C to prepare a saline solution with a salinity of 3% (salinity equal to salt water), and then tuna blocks (lumps) After about 18 minutes, put it out, bite and peel it out, and wash it with water. Then wrap it in a thawing paper or a clean towel, put it in a refrigerator (aging paste) and mature. The saline solution dissolving method has an advantage of osmotic action and can save the taste and color characteristic of the tuna without loss of nutrients. However, there is a problem that the texture is changed according to the treatment method because the condition is difficult.

In this regard, Korean Patent No. 10-1234291 provides a suitable thawing temperature according to the amount and size of the frozen tuna, but the effect of salinity and temperature of the used saline on physical properties and sensory properties of tuna has not been disclosed at all.

The inventors of the present invention have completed the present invention by confirming that the best texture and taste can be achieved by controlling salinity and temperature of saline while studying various aspects in order to improve texture and functionality of tuna.

Korean Patent No. 10-1234291

Accordingly, an object of the present invention is to provide a processing method of a frozen tuna for manufacturing a tuna fish having excellent texture and functionality.

In order to achieve the above object, the present invention provides a method for preparing a frozen tuna block, comprising: (1) charging a frozen tuna block into saline having a salt concentration of 4.5 to 10% and defrosting at 2 to 12 캜 for 1 to 2 hours; (2) removing the thawed tuna block, removing the water and salt by replacing the thawing paper every 2 to 4 minutes while keeping the tuna block at 0 to 5 캜 for 10 to 20 minutes by wrapping with the thawing paper; And (3) freezing the tuna block from which the moisture and salinity have been removed at -60 ° C to -50 ° C for 3 to 7 hours.

The present invention provides a method for improving the texture and functionality of a tuna by defrosting the frozen tuna block using saline having an optimum temperature and saltiness and then freezing the frozen tuna block again, Can be used for the production of tuna conferences.

The terms used herein are defined below.

The term 'tuna' as used in the present invention refers to a tuna which is used for a tuna fish meal. Examples of the tuna fish include Bluefin Tuna (Honma), Bigeye (mebachi), Yellowfin Swordfish, swordfish, striped marlin, macaquiki, albacore, black marlin, black marlin, and tortoiseshell, which contain the tortoise and swordfish, And white marlin (White Marlin, Shirokaki), but the present invention is not limited thereto.

As used herein, the term " tuna block " refers to a chunk frozen by cutting a tuna to a suitable size for each site. The tuna block may be a lump cut from a road (belly button) portion of a tuna, an oboe portion, a main road portion, or an acamy portion.

(1) the frozen tuna block is poured into saline having a salt concentration of 4.5 to 10% and thawed at 2 to 12 캜 for 1 to 2 hours; (2) removing the thawed tuna block, removing the water and salt by replacing the thawing paper every 2 to 4 minutes while being kept at 0 to 5 캜 for 10 to 20 minutes by wrapping in a paper for defrosting; And (3) freezing the tuna block from which the moisture and salinity have been removed at -60 ° C to -50 ° C for 3 to 7 hours.

Hereinafter, a method of processing a frozen tuna according to the present invention will be described in detail.

In the method according to the present invention, in step (1), the frozen tuna block is poured into saline at 4.5-10% salinity and thawed at 2-12 占 폚 for 1-2 hours.

The present invention relates to the physical properties (texture, such as hardness, cohesiveness, elasticity and chewiness) and the toughness (for example, texture and texture) of tuna by thawing frozen tuna blocks in saline at optimal salinity and temperature in the above- , Appearance, freshness and overall acceptability).

The frozen tuna block used in step (1) refers to a frozen tuna block which is usually frozen at -60 ° C to -50 ° C. The size of the frozen tuna block is in the range of 100g to 30kg Size, but is not limited thereto.

The saline solution used in step (1) is prepared by dissolving common salt in water to adjust the salinity to 4.5-10% and the temperature to 2-12 ° C. Conventional saline solution thawing is performed at about 28 ° C using saline solution of 3% salinity similar to that of seawater. It is known that the tuna defrosted by the above method has a clear color and a glossy flow. However, the tuna sashimi defrosted under saline at the above salinity and temperature has not been able to feel the texture of sashimi as a result of the retraction of the texture, and the overall sensibility of the sashimi is also lowered and the value as a tuna society is lowered. In addition, the tuna gob defrosted under saline at the above salinity and temperature has a problem in that freshness is deteriorated easily when it is stored in a refrigerator (aged). On the other hand, the method of the present invention can improve texture of tuna, improve taste, and improve freshness by thawing at a relatively low temperature using saline solution having relatively high salinity.

During the thawing process, water may seep from the tuna block and the salinity of the saline solution may be lowered. Therefore, it is preferable that the salinity of the saline solution is maintained during the thawing process and the salinity of the saline solution is maintained in the range of 4.5-10%.

For smooth thawing of the frozen tuna block, the saline can be used in an amount of 2 to 5 times, preferably 3 times, the volume of the frozen tuna block.

In the thawing step, the frozen tuna block is inserted and mixed well to facilitate the thawing.

Meanwhile, the defrosted tuna block may be further roughened to remove the bones and the skin if they are present.

In the method according to the present invention, in the step (2), the thawed tuna block is taken out and wrapped in a paper for thawing, and the thawing paper is changed every 2 to 4 minutes while being kept at 0 to 5 캜 for 10 to 20 minutes, And salinity.

In this step, water and salt present in the defrosted tuna block are removed and refrigerated. Through the above process, the unique color of the tuna is revived, and the elasticity is improved, so that an optimum condition can be obtained.

Thawing paper (aka, thawing paper) used in the above step is a paper towel used when defrosting a tuna. It is thinner than normal kitchen towels, has a good absorbing power and is highly moisturizing and is used in a high quality Japanese style house. Thawing paper is a fine pulp material, and its surface is smooth and does not stick to the surface of the main material, so it is highly utilized to remove the blood of meat, water and fish such as tuna, as well as water.

The thawing paper is preferably changed every 2 to 4 minutes, preferably 3 minutes, in order to sufficiently remove moisture and salinity.

The refrigerated storage condition in the step (2) may be 0 to 5 ° C for 10 minutes to 20 minutes, preferably 4 ° C for 10 minutes. If the refrigerating storage temperature is higher than the above range or the refrigerating storage time exceeds the above-mentioned time range, the freshness of the tuna may be lowered.

In the method according to the present invention, in step (3), the water and salt-free tuna blocks are frozen at -60 캜 to -50 캜 for 3 to 7 hours.

In the step (3), the frozen and refrigerated tuna are frozen again, and the tuna after the above step is further improved in physical properties and functionality. In addition, since the frozen tuna is improved in texture and taste through the thawing step according to the present invention, it can be thawed at room temperature or thawed in running water without requiring salty water defrosting in a sushi bar or at home. The freezing process is preferably performed as quickly as possible at low temperatures, and can be carried out, for example, by freezing at -60 ° C to -50 ° C for 3 to 7 hours.

The method according to the present invention may further comprise the step (4) of vacuum packing the frozen tuna. The vacuum packaging is very effective in maintaining the improved texture through the thawing step. The vacuum packaging can be performed by a method well known in the art, and the vacuum packed tuna block can be thawed at room temperature or can be thawed by immersing the vacuum pack in flowing water.

In one embodiment, the method of processing frozen tuna according to the present invention may use saline additionally containing chitosan.

That is, in the method according to the present invention described above, chitosan can be further added to the saline used in step (1), and the chitosan used maintains the freshness of the tuna, and further enhances the physical and sensory properties .

The chitosan may be contained in an amount of 0.1 to 2% by weight based on the total amount of saline, but is not limited thereto.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to Examples, but the following Examples are intended to illustrate the present invention without limiting the scope of the present invention.

Example 1: Processing of frozen tuna

200 g of frozen tuna block (fatigue, Odoro) at -60 캜 to -50 캜 was poured into 600 ml of saline at 10 캜 having a salinity of 4.5% and thawed for 1 hour. Saline was poured every 10 to 20 minutes during the thawing process. The thawed tuna blocks were taken out, wrapped in paper for thawing, and stored in a refrigerator at 4 ° C for 10 minutes. During the storage, the thawing paper was changed every 3 minutes. Thereafter, the paper for thawing was removed, and the tuna block was placed in a -60 ° C freezer and frozen for 5 hours. The frozen tuna block was vacuum packed.

Example 2: Processing with saline of different salinity

The procedure of Example 1 was repeated except that the salinity of the saline solution was adjusted to 8% in Example 1 to prepare the frozen tuna of Example 2. [

Example 3: Thawing with saline with different salinity

The procedure of Example 1 was repeated to prepare a frozen tuna of Example 3, except that the salinity of the saline solution in Example 1 was adjusted to 10%.

Comparative Example 1: Thawing with saline of different salinity

The procedure of Example 1 was repeated except that the salinity of the saline solution was adjusted to 2% in Example 1 to prepare a frozen tuna of Comparative Example 1. [

Comparative Example 2: Thawing with saline with different salinity

The procedure of Example 1 was repeated to prepare the frozen tuna of Comparative Example 2, except that the salinity of the saline solution was adjusted to 4% in Example 1 above.

Comparative Example 3: Thawing with saline with different salinity

The procedure of Example 1 was repeated except that the salinity of the saline solution was adjusted to 12% in Example 1 to prepare a frozen tuna of Comparative Example 3.

Comparative Example 4: Thawing with saline with different salinity

The procedure of Example 1 was repeated except that the salinity of the saline solution was adjusted to 15% in Example 1 to prepare a frozen tuna of Comparative Example 4.

Salinity of the saline used in Examples 1 to 3 and Comparative Examples 1 to 4 is summarized in Table 1 below.

Salinity of saline Comparative Example 1 2% Comparative Example 2 4% Example 1 4.5% Example 2 8% Example 3 10% Comparative Example 3 12% Comparative Example 4 15%

Test Example 1: Measurement of physical properties

The frozen tuna prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were immersed in flowing water for 30 minutes and thawed. After about half of the tuna was melted, it was taken out and wrapped in paper for thawing and stored in a refrigerator at 4 ° C for 1 hour. Then, the tuna slices were cut into a size of 15 x 15 x 9 mm and the hardness, cohesiveness, springiness and chewiness were measured using a texture meter (EZ-test, Shimadzu, Tokyo, Japan) . The statistical analysis was repeated three times, and the results were expressed as an average value and a standard deviation.

The measurement results are shown in Table 2 below.

Hardness (× 10 ⁶ dyne / cm ² ) Cohesiveness (%)
Resilience (%) Chewiness (%) Comparative Example 1 3.89 ± 0.48 59.22 ± 2.11 55.15 + - 2.49 389.69 + - 19.55 Comparative Example 2 3.95 + - 0.25 60.15 + - 3.56 56.51 + - 3.56 412.55 + 21.45 Example 1 4.85 ± 0.35 63.24 + - 2.98 62.37 ± 3.11 517.23 + - 18.23 Example 2 5.14 ± 0.34 66.45 + - 2.30 64.19 + - 2.68 623.31 + - 22.20 Example 3 5.71 + - 0.33 67.13 + - 2.44 66.26 +/- 2.59 652.18 ± 20.41 Comparative Example 3 3.33 + - 0.41 59.71 ± 2.53 61.33 + - 3.67 459.56 ± 16.67 Comparative Example 4 2.41 ± 0.29 56.92 + 3.08 59.11 + - 3.24 432.37 ± 17.45

As shown in Table 2, the physical properties of the frozen tuna were significantly different depending on the salinity of the saline used for thawing the frozen tuna.

In particular, Examples 1 to 3 using saline having salinity of 4.5%, 8% and 10% showed better hardness, cohesiveness, elasticity and chewiness, while when the salinity was less than 4.5%, the physical properties such as hardness were lower Respectively. In addition, the higher the salinity, the better the physical properties such as hardness. However, in Comparative Example 3 in which the salinity was more than 10%, the physical properties such as hardness were drastically decreased.

The results show that the frozen tuna can be thawed using saline ranging from 4.5% to 10% in salinity, thereby improving the physical properties during tuna.

Test Example 2: Sensory evaluation

The sensory test was very unsatisfactory (1 point), dissatisfaction (1 point), appearance (freshness) and overall acceptability by the 9-point scale method by 25 sensual agents composed of university students and graduate students majoring in food engineering 2 points), usually dislikes (3 points), slightly dislikes (4 points), dislikes not good (5 points), slightly better (6 points), normal (7 points), good (8 points) (9 points).

The sensory evaluation was expressed by the mean value and standard deviation of 25 sensory agents.

The results of the test are shown in Table 3.

Exterior Freshness Comprehensive likelihood Comparative Example 1 5.99 ± 0.28 4.77 ± 0.92 5.84 + - 0.67 Comparative Example 2 6.01 ± 0.54 5.08 ± 0.44 6.23 ± 0.27 Example 1 6.24 ± 0.75 6.33 + - 0.41 8.11 ± 0.36 Example 2 6.18 ± 0.69 6.45 ± 0.86 8.06 + - 0.41 Example 3 6.22 + - 0.74 6.71 + - 0.39 8.26 ± 0.31 Comparative Example 3 6.34 ± 0.61 4.28 ± 0.56 6.35 ± 0.29 Comparative Example 4 6.44 ± 0.38 4.07 ± 0.76 6.47 + - 0.44

As shown in Table 3, in the case of the tuna fermentation of Examples 1 to 3 in which the saline was dissolved using saline having the salinity of 4.5%, 8% and 10% Respectively.

The salinity of salty water was 4.5%, 8% and 10%, respectively, but the freshness was significantly improved and the overall preference was improved by improving the texture.

The results show that the frozen tuna can be thawed using saline ranging from 4.5% to 10% in salinity to improve the sensory characteristics of the tuna.

Example 4: Processing with saline at different temperatures

The procedure of Example 1 was repeated except that the temperature of the saline solution was adjusted to 2 캜 in Example 1 to prepare the frozen tuna of Example 4.

Example 5: Processing with saline at different temperatures

The procedure of Example 1 was repeated except that the temperature of the saline solution was adjusted to 12 캜 in Example 1 to prepare the frozen tuna of Example 5.

Comparative Example 5: Processing with saline at different temperatures

The procedure of Example 1 was repeated except that the temperature of the saline solution was adjusted to 15 캜 in Example 1 to prepare a frozen tuna of Comparative Example 5.

Comparative Example 6: Processing with saline at different temperatures

The procedure of Example 1 was repeated to prepare the frozen tuna of Comparative Example 6, except that the temperature of the saline solution was adjusted to 25 캜 in Example 1 above.

The temperatures of the saline used in Examples 4 and 5 and Comparative Examples 5 and 6 are summarized in Table 4 below.

Saline temperature Example 4 2 ℃ Example 5 12 ° C Comparative Example 5 15 ℃ Comparative Example 6 25 ℃

Test Example 3: Measurement of physical properties

The properties of the frozen tuna prepared in Examples 4 and 5 and Comparative Examples 5 and 6 were measured in the same manner as in Test Example 1. For reference, the frozen tuna prepared in Example 1 were compared.

The measurement results are shown in Table 5 below.

Hardness (× 10 ⁶ dyne / cm ² ) Cohesiveness (%)
Resilience (%)
Chewiness (%)
Example 1 4.85 ± 0.35 63.24 + - 2.98 62.37 ± 3.11 517.23 + - 18.23 Example 4 4.35 0.46 60.19 + - 2.15 60.41 + - 3.05 492.14 ± 20.17 Example 5 4.23 + - 0.44 59.86 ± 2.29 59.33 ± 2.96 484.17 ± 19.36 Comparative Example 5 3.71 + - 0.38 59.71 ± 2.53 51.29 ± 3.09 367.39 ± 17.49 Comparative Example 6 3.06 ± 0.38 56.92 + 3.08 45.11 + - 3.37 312.27 ± 20.97

As shown in Table 5, the physical properties of the frozen tuna were significantly different according to the temperature of the saline used for thawing the frozen tuna.

Especially, as the temperature of saline solution increased, the hardness, cohesiveness, elasticity and chewiness were not good. Especially, when the temperature of saline solution exceeded 12 ℃, the physical properties decreased rapidly.

The above results show that the frozen tuna can be thawed using saline at a temperature of 2 to 12 占 폚 to improve the physical properties during tuna.

Comparative Example 7: Manufacture of unfrozen tuna

The tuna of Comparative Example 7 was prepared by repeating the procedure of Example 1 except that the tuna defrosted in Example 1 was refrigerated and not frozen.

Test Example 4: Measurement of physical properties

The properties of the tuna produced in Example 1 and Comparative Example 7 were measured in the same manner as in Test Example 1.

The measurement results are shown in Table 6 below.

Hardness (× 10 ⁶ dyne / cm ² ) Cohesiveness (%)
Resilience (%)
Chewiness (%)
Example 1 4.85 ± 0.35 63.24 + - 2.98 62.37 ± 3.11 517.23 + - 18.23 Comparative Example 7 2.47 ± 0.54 42.36 ± 3.34 39.25 + - 3.09 274.66 + - 18.54

As shown in Table 6, the tuna of Comparative Example 7, which had not been frozen after being thawed using saline, showed poor physical properties. On the other hand, tuna after freezing was re-cooled at a temperature of -60 ° C to -50 ° C The better the physical properties.

According to the conventional saline defrosting method, it is preferable to freeze the tuna one more time after defrosting the saline solution.

Example 6: Processing of frozen tuna using chitosan

The procedure of Example 1 was repeated, except that 0.2% of chitosan (green biotech) was added to the saline in Example 1 to prepare the frozen tuna of Example 6.

Test Example 4: Measurement of physical properties

The tuna produced in Example 6 was measured for physical properties in the same manner as in Test Example 1. For reference, it was compared with the frozen tuna prepared in Example 1.

The measurement results are shown in Table 7 below.

Hardness (× 10 ⁶ dyne / cm ² ) Cohesiveness (%)
Resilience (%)
Chewiness (%)
Example 1 4.85 ± 0 ^. 35 63.24 + - 2.98 62.37 ± 3.11 517.23 + - 18.23 Example 6 5.36 + 0.33 65.28 ± 2.41 66.38 + - 3.74 537.68 ± 20.78

As shown in Table 7, when the chitosan was added to the saline solution, the physical properties were further improved. These results demonstrate that chitosan is effective in improving the physical properties of tuna.

Claims

(1) placing the frozen tuna block in saline at a salt concentration of 4.5-10% and thawing at 2-12 占 폚 for 1-2 hours;
(2) removing the thawed tuna block, removing the water and salt by replacing the thawing paper every 2 to 4 minutes while keeping the tuna block at 0 to 5 캜 for 10 to 20 minutes by wrapping with the thawing paper; And
(3) freezing the tuna block from which the moisture and salinity have been removed at -60 캜 to -50 캜 for 3 to 7 hours
Of the frozen tuna for tuna.

The method according to claim 1,
(4) vacuum packing the frozen tuna block.

The method according to claim 1,
Wherein the saline comprises chitosan.