JP4297842B2 - Large fish split package and manufacturing method thereof - Google Patents

Description

  The present invention relates to a split package that effectively maintains the quality of fresh large fish, particularly fresh tuna, and has a small amount of drip outflow, and a method for producing the same.

  Large fish, especially tuna, skipjack, etc., when exposed to air in the air by cutting, cause discoloration due to oxidation of the main pigment myoglobin and off-flavor due to lipid oxidation, resulting in loss of commercial value in 1-2 days. Therefore, when storing or transporting tuna, bonito, etc. refrigerated (unfrozen), avoid exposing the flesh surface, “round” (entirely), “GG or semi-dressed” (with moths and internal organs removed) In general, it takes the form of a “dress” (with the heel, internal organs, and head removed).

  Recently, as a new trial, after tuna was divided in the tuna production area, a method of closely packaging and distributing with a plastic film with low oxygen gas permeability was devised. Compared to the above round, GG, dress-type transport, Since unnecessary parts are removed in advance, the transportation cost is low and the disposal process at the time of final processing can be saved. “Because it is packaged by part, end distributors can easily purchase only the products they want” (Patent Document 1). Therefore, the packaging method has been put into practical use in the field of farmed tuna, but on the other hand, as a new problem, the separation of tuna gravy (drip) into the tightly packed package has been pointed out. That is, in order to obtain a tightly packed body, the tuna block is deaerated and tightly wrapped using a vacuum packaging machine, but since the inside of the package is decompressed, the drip outflow from the tuna block is promoted, and the time after packaging At the same time, the problem of increased drip spillage has been pointed out.

The drip spillage not only leads to product loss due to deterioration of the appearance of the package and the net weight loss of the fish meat, but can also cause a substantial deterioration of the quality of the fish meat. For example, it is known that a drip staying in a package causes the fish meat to soften and cause discoloration or a decrease in texture. In addition, when a skinned fish meat block is packaged, bacteria attached to the skin surface may propagate along with the drip to a clean edible portion, and the entire fish meat may be contaminated with bacteria. Therefore, it is desirable that the amount of drip flowing out in the package is as small as possible, and even if it has a slight drip reduction effect, the merit is very large. As a drip prevention measure, a drip absorbent material is generally inserted into the package to prevent a drop in the appearance of the product due to the drip. (Yield reduction) cannot be suppressed (Patent Document 1). In addition, due to the absorbability of the drip absorbent material itself, the juice may be forcibly sucked from the fish meat. In addition, although it is considered that relaxation of the decompression conditions during close-packaging is effective in suppressing drip loss, there is a problem that bubbles due to insufficient deaeration remain and oxidation discoloration occurs in the portion.
WO03 / 024236 Publication

  The present invention reduces the drip loss during storage and distribution that has been pointed out in the division packaging technology for large fish such as tuna using the plastic film as described above, and achieves the improvement in yield of the tuna edible portion It is an object to provide a package and a manufacturing method thereof.

  In the current tuna shipment (round, GG, semi-dress, dress-type shipment), after picking up the tuna, soak it in ice or ice water and let it stand for at least one night, tuna fish body temperature (core temperature) It is common sense to reduce the temperature to around 5 ℃ before shipping. This is based on an empirical fact that when the tuna body temperature is left at a high temperature (approximately 15 to 20 ° C or higher), discoloration of the meat called burnt occurs. When tuna is currently packaged and shipped separately, it is not an exception, and the actual situation is that tuna fish body temperature (core temperature) is lowered to about 5 ° C and then packaged in packages. Normally, when the tuna landed in a live state is beaten and then cooled overnight in ice, the freshness index K value exceeds 3%. That is, it can be said that the current tuna shipping or split packaging is performed after the K value exceeds 3%.

The K value of the freshness index here indicates the degree of enzymatic degradation of ATP-related compounds contained in fish meat, and is expressed by the following formula and is widely used as a freshness index for fish meat. The K value changes depending on the temperature and time, and shows a larger value as the fish meat temperature is higher or the elapsed time is longer.

As a result of repeated research to solve the above problems, the inventors have observed the above-mentioned current situation, and obtained a block having a freshness index K value of 3% or less obtained by dividing a large fish into a tightly packed package using a plastic film. Later, it was found that by storing or transporting at temperatures below 10 ° C, the drip loss of large fish blocks was reduced and the yield of large fish edible parts was improved.
In addition, although this invention is applied also to large fish, such as a skipjack, since tuna is mainly applied, tuna is demonstrated here. However, this does not exclude application to large fish such as skipjack.

  For example, if the tuna is caught and then put in ice, removed within 6 hours and divided into blocks, the K value at that time will be 3% or less. The shorter the ice cooling time of the tuna after drought, the lower the K value. Tuna divided into blocks under such a condition that the K value is 3% or less is subjected to close packaging such as vacuum packaging with a plastic film and cooled at a temperature of 10 ° C. or less. This cooling is performed while being stored or transported. This makes it possible to reduce the drip loss during storage or transportation and improve the yield of the tuna edible portion as compared with the current divided package. In addition, since the cooling time of the tuna fish is shortened, the effect of being able to ship tuna with high freshness accordingly is expected. (The mechanism of drip loss reduction is not clear, but the higher the freshness, the better the water retention of tuna meat. (It is thought that it contributes to the reduction.)

That is, this invention is the following large-scale fish division package and its manufacturing method.
(1) A block with a freshness index K value of 3% or less , obtained by dividing a large fish, is tightly packed with a plastic film, and then cooled at a temperature of 10 ° C or less. Fish split package.
(2) The large fish split package with a small amount of drip spillage according to (1), wherein the large fish is a tuna.
(3) A drip characterized in that a block having a freshness index K value of 3% or less obtained by dividing a large fish is closely packed with a plastic film and then cooled at a temperature of 10 ° C or less. A method for producing a split package of large fish with a low outflow.
(4) The large fish split package of (3), wherein the large fish is selected from bluefin tuna, southern bluefin tuna, bigeye, and albacore having a weight of 10 kg or more. Manufacturing method.
(5) The method for producing a split package of large fish with a small amount of drip outflow according to any one of (3) and (4), wherein the weight of the block is 1 kg or more and 20 kg or less.
(6) The oxygen gas permeability of the plastic film at 0 ° C. and drying conditions (0-10% RH) is 20 cm ³ / m ² · d · atm or less (3) to (5) The manufacturing method of the division | segmentation package body of the large fish with little drip outflow amount in any one of.

  In the present invention, when the large fish is selected from tuna, particularly, bluefin tuna having a weight of 10 kg or more, southern bluefin tuna, bigeye tuna, or albacore, the tuna is divided into blocks and tightly packaged with a plastic film. This close-packed package should be cooled (stored or transported) at a temperature of 10 ° C or less. If the tuna weighs less than 10 kg, the advantage of shipping in divided blocks is less likely to occur than when shipping in round, GG, semi-dress or dress.

  Further, when the weight of the block obtained by dividing the tuna is 1 kg or more and 20 kg or less, the block is tightly packed with a plastic film to produce a tightly packed body. This close-packed package should be cooled (stored or transported) at a temperature of 10 ° C or lower. When the weight of the tuna block is less than 1 kg, even if the drip loss is reduced by the method of the present invention, the drip loss ratio in the tuna weight is still high, which is not preferable in terms of the yield of the tuna edible portion. Further, when closely packed in a very high fresh state with a K value of 3% or less, a “lift phenomenon” as shown in FIG. 1 occurs due to post-mortem stiffening (muscle contraction) after packaging. In the case of a small block having a weight of less than 1 kg, the bulge is conspicuous and the appearance of the product may be impaired. Therefore, the package of the present invention preferably uses a block of 1 kg or more, more preferably a block of 3 kg or more. It is preferred to do so. If the block weight exceeds 20 kg, close packaging becomes difficult due to the size of the block, and the handling of the package is also unfavorable.

Furthermore, the block of freshness index K value 3% or less obtained by dividing the tuna has an oxygen gas permeability of 20 cm ³ / m ² · at 0 ° C and dry conditions (0-10% RH). Cooled (stored or transported) at a temperature of 10 ° C or less after tight packaging with a plastic film of d · atm or less. If the oxygen gas permeability exceeds 20 cm ³ / m ² · d · atm, discoloration due to oxidation of the tuna block occurs, which is not preferable.

The plastic film used for close-packaging has an oxygen gas permeability of 20 cm ³ / m ² · d · atm or less, preferably 12 cm ³ / m ² · d · atm or less at 0 ° C and dry conditions (0-10% RH), More preferably, it is 7 cm ³ / m ² · d · atm or less, and most preferably 3 cm ³ / m ² · d · atm or less. Thereby, the oxidation of tuna fish meat can be suppressed, and as a result, quality deterioration such as discoloration can be suppressed. When the oxygen gas permeability exceeds the above range, discoloration of tuna fish (myoglobin methalation) and lipid oxidation occur, and the quality as a product is impaired. The oxygen gas permeability is measured in accordance with ASTM D3985-81 using a Mocon ^™ Oxytran Model 100 manufactured by Modern Controls Inc. at 0 ° C. and 0-10% RH.
As the plastic film, one made of a single material or a plurality of materials is used. Usually, a film in which two or more kinds of materials are laminated is used, and there are no particular restrictions on the material, but polyester, nylon (nylon 6, nylon 66, nylon 12, nylon 6 and nylon 66 copolymer, nylon 6 and Nylon 12 copolymer, etc.), polyethylene (low density polyethylene, linear low density polyethylene, ultra low density polyethylene, etc.), polypropylene, copolymers of ethylene and vinyl acetate, ionomers, polyvinyl chloride, polyvinylidene chloride, A copolymer of ethylene and vinyl alcohol is used. In addition, in the case of a film in which two or more kinds of materials are laminated, it is manufactured by a coextrusion method or a lamination method.
In laminating films, conventionally known adhesives can be used if necessary.

  The large-sized block-divided close-packed package of the present invention is packaged in a state where the K value is very low compared to the conventional technology, so even if it is cooled (stored or transported), the amount of drips flowing out is extremely high. In addition, it is possible to obtain a large-sized fish block body having a low quality and little discoloration. The present invention is particularly suitable for tuna block-divided close-packed packages.

Hereinafter, preferred embodiments of the present invention will be described, but the present invention is not necessarily limited to these examples.
In the present invention, a close-packed package is produced with a plastic film of blocks having a freshness index K value of 3% or less obtained by dividing tuna . The tightly packed package is cooled (stored or transported) at a temperature of 10 ° C or lower.
Here, the K value of tuna is 3% or less, preferably 2% or less, and more preferably 1% or less. If the K value exceeds 3%, drip generation during storage of the block-packed product increases, which is not preferable. To obtain a tuna block with a K value of 3% or less, the tuna after landing is ice-cooled and then divided into blocks within about 6 hours and at least within 8 hours. Also, after picking the tuna after landing, place it in a freezer at -20 ° C or lower, or immerse it in a brine solution (salt solution such as calcium chloride or alcoholic solution) at -20 ° C or lower, or dry ice It is possible to achieve a K value of 3% or less by means such as using a refrigerant. However, if the tuna meat is exposed to the freezing temperature (-1 to -2 ° C) or lower for a long time, the tuna meat freezes and drip leaching or discoloration may occur due to freezing and thawing. While cooling carefully.

In addition, the plastic film packaging is preferably a close packaging such as vacuum packaging. Although close-packaging by wrapping packaging is possible, care must be taken because air may be discolored when air is caught between the film and the tuna block. In addition, the close-packed packaging here includes deaerated packaging. Degassing packaging methods include nozzle-type degassing (a method in which air in the packaging bag is degassed by a nozzle) and chamber-type degassing (depressurizing the inside of the chamber with a vacuum packaging machine to degas the inside of the packaging bag. Then, the mouth is sealed). Most of vacuum packaging is performed by the chamber type deaeration method, and there are a manual type chamber type vacuum packaging machine, an automatic type rotary vacuum packaging machine, a deep drawing type automatic vacuum packaging machine, and the like. In addition, when packaging with a plastic film, you may attach a water absorbing material with a tuna block. Due to the effect of the present invention, the drip outflow from the tuna block is significantly reduced compared to the prior art, but not completely absent. The water-absorbing material absorbs a small amount of drip generated in the package, so that the appearance of the package becomes more preferable. In the case of the present invention, since the drip outflow is reduced as compared with the prior art, it is possible to cope with even a small amount of water-absorbing material having a low water-absorbing ability. By using a water-absorbing material having a smaller amount or a lower water-absorbing capacity than conventional ones, it is possible to avoid the problem that liquid juice is forcibly absorbed from fish meat. The form of the water-absorbing material is not particularly limited, but the form is a film or sheet that is easy to handle. Examples of the material include starch, cellulose, polyacrylic acid, polyvinyl alcohol, and polyacrylamide. Or polyoxyethylene-based substances can be used singly or in combination.
Cooling (storage or transport temperature) after close-packaging is preferably 10 ° C or lower, more preferably 5 ° C or lower. More preferably, it is -1 to 2 ° C. If the storage or transport temperature exceeds 10 ° C, the growth of bacteria attached to the tuna block and the freshness of the tuna meat are promoted and the shelf life is shortened, which is not preferable. As a method of keeping the tuna block after close-packing at 10 ° C or less, it can be stored in a refrigerator or container having an internal temperature of 10 ° C or less, and stored in a cold storage container such as an expanded polystyrene box or cardboard box together with a refrigerant such as ice. There are ways to transport. If it is divided into blocks and packaged within a short time after landing, and put in a cold storage container with ice as it is, delivery can be performed in a state of high freshness that is not conventional, which is preferable.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

After landing the cultured bluefin tuna with a body weight of about 50 kg, crawl, remove the pupae and internal organs, put it in ice water, and after 1 to 2 hours, take a 9 kg weight loin, and then add 5 blocks of 1 to 2 kg weight ( It was divided into A, B, C, D, and E) from the head side. For block E meat, normal meat was collected, and the amount of ATP-related compound was promptly analyzed by liquid chromatography (HPLC method) to calculate the K value. That is, after dividing Block E meat, immediately collect 4 g of the surface, add 10 ml of 1M perchloric acid, homogenize, centrifuge (3000 rpm, 5 minutes), take the supernatant, take 1M potassium bicarbonate solution To adjust the pH to 6.5. The supernatant of the sample solution after pH adjustment was filtered through a membrane filter, 5 μl of the filtrate was injected into HPLC, and ATP-related compounds were analyzed based on the following conditions.
a) Column: STR ODS-II (4.6mmφ × 150mm) ^* Combined with STR ODS-II guard column
b) Moving bed: 100 mM phosphate (triethylammonium) buffer solution (pH 6.8) / acetonitrile = 100 / l (v / v)
c) Temperature: 40 ° C
d) Flow rate: 0.5ml / min
e) Detection method: Absorbance measurement at 260nm
f) System used: LC-VP HPLC system manufactured by Shimadzu Corporation As a result of the analysis, the concentration of the obtained ATP-related compound was applied to the formula for calculating the K value described in [0008] to calculate the K value. For the four blocks A to D, a plastic film pouch with an oxygen gas permeability of 2 to 3 cm ³ / m ² · d · atm at 0 ° C. and dry conditions (0 to 10% RH) (Kureha Chemical Industries ( Kurehalon VS-20 (Resin composition: PET / ad / PA / EVOH / ad / PE, Total thickness: 40μm (PET: Polyethylene terephthalate, PA: Polyamide, EVOH: Ethylene-vinyl alcohol copolymer, PE: Polyethylene) , Ad: adhesive layer)), vacuum packaged, packed in a polystyrene foam box with ice, stored for 1 day, and stored in a refrigerator at 5 ° C from the second day. After 3 days, 6 days, 9 days, and 13 days, the package is opened, the drip generated in the package is collected and weighed, the ratio to the original block weight is calculated, and the drip spill rate (% )

  It was carried out in the same manner as in Example 1 except that the tuna division time was 3-4 hours after the landing, removing the straw and viscera after placing it in the ice water.

  It was carried out in the same manner as in Example 1 except that the tuna division time was 6 to 7 hours after the landing, after removing the straw and viscera after putting it in the ice water.

Comparative Example 1

  It was carried out in the same manner as in Example 1 except that the tuna division time was 10 to 11 hours after the landing, after removing the straw and the internal organs after putting it in the ice water.

Comparative Example 2

  It was carried out in the same manner as in Example 1 except that the tuna division time was 16 to 17 hours after the landing, after removing the straw and viscera after putting it in the ice water.

These drip discharge rates are shown in Table 1 and FIG.
As shown in Table 1 and FIG. 2, in the case of Examples 1 to 3 packaged when the K value was 3% or less, compared to Comparative Examples 1 and 2 packaged when the K value was 3.5% and 4.6%. The drip outflow rate (ratio of outflow drip weight to the original tuna block weight) was clearly low, the appearance of the block package was excellent, and the yield of the tuna edible part was also improved. Furthermore, Examples 1-3 were able to ship a block package goods 12 hours or more earlier than Comparative Examples 1-2, and were excellent also from the viewpoint of quick delivery.

Further, the appearance of the tuna cooling divided package obtained in Example 3 and the tuna cooling divided package obtained in Comparative Example 2 are shown in FIG.
Comparing the two, it can be seen that the appearance of Example 3 is more beautiful and the amount of drip is obviously smaller than that of the comparative example.

The comparison of the fish bulge (arrow part) in Example 1 and Comparative Example 2 is shown. The drip outflow rate of the tuna according to K value at the time of packaging of Examples 1-3 and Comparative Examples 1-2 is shown. A comparison of the appearance of Example 3 and Comparative Example 2 on the 13th day after catching is shown.

Claims (6)

A large fish split package with a small amount of drip spillage , which is obtained by closely packaging a block with a freshness index K value of 3% or less obtained by dividing a large fish with a plastic film and then cooling it at a temperature of 10 ° C or less. body.   2. The large fish split package with a small amount of drip spillage according to claim 1, wherein the large fish is a tuna. A block with a freshness index K value of 3% or less , obtained by dividing a large fish, is closely packed with a plastic film, and then cooled at a temperature of 10 ° C or less. A method for producing a small divided fish package.   4. The method for producing a split package of large fish with a small amount of drip outflow according to claim 3, wherein the large fish is selected from bluefin tuna, southern bluefin tuna, bigeye tuna, and albacore having a weight of 10 kg or more. .   The method for producing a split package of large fish with a small amount of drip discharge according to any one of claims 3 and 4, wherein the weight of the block is 1 kg or more and 20 kg or less. 6. The oxygen permeability of the plastic film at 0 ° C. and drying conditions (0-10% RH) is 20 cm ³ / m ² · d · atm or less, according to any one of claims 3 to 5. Method for split packaging of large fish with low drip spillage.