JPH04335873A - Method for softening and maturing meat - Google Patents

Abstract

PURPOSE:To accelerate the softening and maturing of meat such as beef or pork. CONSTITUTION:The mass of meat is put in a bag resistant to high pressures, deaerated, sealed and subjected to a high pressure of 1500-2000kg/cm<2> for 5-10min. The softening and maturing of the meat are thereby accelerated without requiring the storage of the meat in a refrigerator for a long time. Even the meat exhibiting only limited effect of the softening after the conventional maturing period is improved and given the entirely same improved flavor as that of conventionally matured meat.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for softening and aging meat.

0002

BACKGROUND OF THE INVENTION Generally, skeletal muscles of livestock are used as meat. After a certain period of time has passed after a livestock animal is slaughtered, its muscles change from a relaxed, flexible state to a state of ``rigor mortis'' in which they lose their extensibility and harden. Immediately after slaughter, meat is tender but lacking in flavor, while meat that is still being cured is hard and unsuitable for cooking and processing. If you refrigerate stiff meat for a few days, the stiffness will be removed and the meat will regain its tenderness and develop its unique flavor. In this way, beef is refrigerated for a certain period of time after slaughter to release the stiffness that has occurred in the carcass, and to increase the taste. It will take 10 to 14 days to complete. After this aging period, the meat is sold.

0003

[Problems to be Solved by the Invention] The conventional technology has the following problems. First, when beef is refrigerated at 4°C to 5°C, it takes 10 to 14 days to complete ripening, which requires a large refrigerated space and a large amount of refrigeration energy, leading to an increase in production costs. Secondly, there is a limit to the improvement of the meat quality of cows that are inherently hard, such as dairy cows, even after ripening, and their commercial value is estimated to be low. Third, beef, which is often imported in a frozen state, needs to be refrigerated and aged for several days after thawing to improve its quality and flavor. These problems are common not only to beef but also to other meats such as pork. The technical object of the present invention is to solve these problems and provide a method for promoting the softening and ripening of meat.

0004

[Means for Solving the Problems] The present invention was made to solve the above-mentioned technical problems, and after putting a lump of meat into a flexible bag that can withstand high pressure and deaerating and sealing it, It is constructed to soften meat and promote ripening by applying hydrostatic pressure for a required period of time.

[0005]

[Example] In the example of the present invention, from a practical point of view, beef meat lumps immediately after rigor mortis were placed in a flexible bag that can withstand high pressure, degassed and sealed, and then
After pressurizing with hydrostatic pressure for the required time, the pressure is returned to normal pressure to promote tenderization and ripening of the meat. The pressurization method involves placing beef chunks in a flexible bag such as vinyl, deaerating the bag, sealing it, and transferring it to a high-pressure processing device. Pressure treat. As pressure medium, liquids are used in the present invention, in particular water due to its food safety and handling convenience.

[0006] The meat mass is uniformly pressurized over its entire surface by a liquid pressure medium, causing physical changes in the proteins constituting the meat mass, which promotes the softening and ripening of the meat. Hereinafter, it will be explained in more detail using specific examples.

[0007] 1000, 1500, 2000 for beef chunks
, 3000 kg/cm2 for 5 minutes, and then subjected to two reciprocating mastication tests using a rheometer. The results are shown in FIG. The h written on the texture curve of the untreated area (control) represents the hardness, and b/
a indicates elasticity. As is clear from the figure, as the processing pressure increases, the hardness (h
) decreases. Table 1 shows the relative values of hardness and elasticity of the pressure-treated area, with the untreated area being taken as 100.

[0008]

[Table 1]

[0009] The hardness is about 60% of untreated at a pressure of 1000 kg/cm2, 1500 and 2000 kg/cm2.
2, the pressure decreased to about 20% to 30% of the untreated area.
At 3,000 kg/cm2, the rate decreased to about 10%, but the color of the meat changed to the color when it was heated. Myofibrils were prepared from the high-pressure processed meat, observed using a phase contrast microscope, and the degree of fragmentation was determined using the following formula, and the relationship with processing pressure is shown in Figure 2.

0010

[Math 1]

[0011] The degree of fragmentation was 10% in the untreated area, but in the 1000, 1500, 2000, and 3000 k
g/cm2 pressure, 30% or more, 7
It increased to 0% or more, 80% or more, and 90% or more. Myofibrils prepared from aged meat are shorter and have fewer sarcomeres than those prepared from unripened meat, and the destruction of Z-lines of myofibrils causes fragmentation and tenderization of the meat. It is well known that it is related to Therefore, fragmentation of myofibrils is considered to be an indicator of meat tenderization. As shown in Fig. 2, the myofibrillar meat mass increased in an S-shape with the increase in pressure applied to it, and by high-pressure treatment for 5 minutes, naturally aged meat (10 days at 4-5℃) It was revealed that fragmentation reached a maximum level of about 90% after 14 days). Based on the fragmentation of myofibrils into small pieces, it was confirmed that high-pressure treatment of meat immediately after hardening is an effective means of softening and aging meat.

Next, as a result of observing the fine structure of myofibrils prepared from high-pressure-treated meat using an electron microscope, it was found that 1500 k
g/cm2 pressure treatment, the destruction of the filament structure in the I band and the disappearance of the M line became severe, and the treatment pressure increased to 2000 k.
g/cm2, the structural continuity of the sarcomere was almost completely lost, and the destruction of A-filaments and I-filaments spread throughout the sarcomere. The fragmentation of myofibrils that occurs in normal aged meat is due to the weakening of the Z-line, and there is no major change in the structure of the A-band or I-band. However, almost no change was observed in the Z-line of myofibrils prepared from pressure-treated muscle and cut into small pieces. It is known that polymers of F-actin, myosin, and actomyosin, which are the main components of myofibrils, are depolymerized by pressure treatment. That is, depolymerization of F-actin to G-actin is considered to be one of the causes of fragmentation of myofibrils.

[0013] As described above, the high-pressure treatment of beef immediately after rigor mortis has made it possible to soften and age the meat in a mechanism different from that of normal aging. Moreover, a short treatment time of 5 to 10 minutes was sufficient. In addition, as shown in the test examples described below, even in cases where the meat is inherently hard, such as dairy cows, and no improvement in hardness is observed even after the normal aging period, the softening effect is fully demonstrated. did. As seen in the same test example, the high-pressure treatment increased the amount of taste-producing amino acids and peptides compared to the untreated area, demonstrating the effectiveness of high-pressure treatment in improving the flavor of beef.

Next, test examples of the present invention will be shown. In all of the test examples (1) to (3) shown below, the high-pressure treatment equipment used for high-pressure treatment was manufactured by Nippon Kokan Co., Ltd., Cold Isos.
tatic Press (CIP) Apparatus
It was used.

Test Example 1 [0015] Shoulder loin of a dairy cow (7-year-old female) 4 days after slaughter was purchased and stored at -25°C until use. After thawing, the meat was cut into 50 x 50 x 30 mm pieces, placed in a polyethylene bag, degassed and sealed, then placed in a larger vinyl bag with ice water, transferred to a high-pressure container, and pressurized. Prepare five materials (one of which is untreated area), and each at 1000, 1500, 2000, and 3000 kg/c.
The pressure was increased to m2, and after reaching a predetermined pressure, it was held for 5 minutes, and then returned to normal pressure, and the sample taken out was immediately cooled on ice. The temperature during pressure treatment was kept below 5°C. When a chewing test was conducted using a rheometer, the result was 1500-2.
The pressure treatment at 000 kg/cm2 reduced the hardness to 20-30% of the untreated area, and the softening of the meat was significantly promoted. When the fragmentation of myofibrils was observed using a phase contrast microscope using a conventional method, it was found that at 1500 kg/cm2, the fragmentation of myofibrils was more than 70%.
000 kg/cm2, it was 80% or more, and promotion of softening was also confirmed histologically. By observation using an electron microscope,
It was found that among the microstructures of myofibrils, collapse of the I band and A band causes the myofibrils to fragment into small pieces. 3000kg/c
The meat that was subjected to the pressure treatment at m2 changed its color to a slightly brownish color similar to when it was heated, and showed a tendency to be visually inferior, but it was found that the above-mentioned change was further accelerated. In this test example, the frozen meat was thawed and then pressurized, but it is possible to obtain the same softening effect even if the frozen meat is pressurized without thawing. In that case, the pressurization time is 10 to 15 minutes. You can postpone it for as long as you like.

Test Example 2 I purchased the shoulder loin of a dairy cow that had been aged for 14 days after slaughter, sliced it into 3 mm thick pieces, roasted it in a frying pan, and tasted it.It was very tough. This meat was cut into blocks of 200 x 100 x 100 mm, placed in a plastic bag, degassed and sealed, and then placed in a large plastic bag with ice water, then transferred to a high-pressure container and heated at 1500, 2000, and 3000 kg/cm2 for 5 minutes. Pressurized. After returning to normal pressure, the meat loaf was taken out, sliced into 3 mm thick slices, roasted in a frying pan, and subjected to a sensory test for firmness, color, and flavor. 14 tasted
All the subjects judged that the products pressurized at 1500 and 2000 kg/cm2 were superior in softness and flavor compared to the untreated group. 1500kg/cm2 and 200
The judgment was divided as to which pressure treatment at 0 kg/cm2 was superior. Meat pressurized at 3000 kg/cm2 is soft, but it is
It was determined that the flavor was lacking compared to the one pressurized at 0 kg/cm2. In addition, as shown in Test Example 1, meat pressurized at 3000 kg/cm2 lost its original red color and tended to be visually inferior.
It was found that the aforementioned changes upon pressure treatment were further accelerated.

Test Example 3 Purchase the shoulder loin of a dairy cow 4 days after slaughter, cut it into chunks of 50 x 50 x 30 mm, put it in a polyethylene bag, degas and seal it, and then put it in a large plastic bag with ice water. After that, transfer it to a high pressure container and
5 at 0,1500,2000,3000kg/cm2
Pressure was applied for a minute. After returning to normal pressure, take out the material, cut it into pieces, homogenize it with 2.5 times its weight of distilled water, and wash it for 10 minutes.
,000 rpm/min for 15 minutes to obtain an extract. TCA was added to this extract to precipitate proteins, and the phenol reagent positive substance in the supernatant was quantified. A portion was also subjected to amino acid analysis using a Hitachi amino acid automatic analyzer.

[0018]

[Table 2]

Table 2 shows the measured values of phenol reagent positive substances (corresponding to the content of amino acids and peptides) extracted from 100 g of beef. This result indicates that the high-pressure treatment increased the total amount of taste-producing substances in beef. The amount of increase was particularly large when a pressure of 2000 kg/cm2 was applied. Next, among the individual amino acids and peptides, Table 3 shows the quantitative values of amino acids and peptides that are involved in the taste of meat such as sweetness and umami.

[0020]

[Table 3]

As is clear from the table, almost all amino acids showed a tendency to increase upon high pressure treatment. The above results are thought to be due to the fact that some of the protein in the meat was decomposed by the high-pressure treatment, or the structure of the meat became loose, which increased the ability to extract taste substances. Although data is not shown, a portion of the pressure-treated meat was heated to 7°C at a low temperature of 2 to 4°C.
After storage for several days, the phenol reagent-positive substances and individual amino acids were quantified in the same manner as described above. As a result, the taste substance content increased in all treated plots, including the untreated plot. Among them, the rate of increase was the highest in the 1500 and 2000 kg/cm2 pressure treated sections. This is thought to be because the pressurization weakens the lysosomal membrane in beef, increasing the degree of contact between intramuscular proteolytic enzymes (cathepsins), which are involved in the increase in taste substances, and muscle proteins, which serve as their substrates. . These results indicate that high-pressure processing can soften meat and improve its flavor at the same time.

[0022] The present invention is not limited to the above-mentioned examples; for example, in the present examples and test examples, high-pressure treatment was performed on shoulder loin of a high-value-added dairy cow; Of course, similar effects can be obtained with beef and other meats such as pork and mutton.

[0023]

[Effects of the Invention] The present invention is capable of softening the meat and promoting ripening by placing a lump of meat in a flexible bag that can withstand high pressure, deaerating and sealing the bag, and then applying hydrostatic pressure for a required period of time. This structure allows meat to soften and soften without going through the long refrigeration period required for conventional aging.
It has the effect of accelerating maturation, improving the quality of meat such as dairy cows, which have limited softening effects even after a normal maturing period, and improving the flavor, which is completely the same as normal maturing. Furthermore, since a long ripening period is not required, it also has the effect of saving refrigerated space and energy.

[Brief explanation of the drawing]

[Figure 1] Beef for 1000, 1500, 2000, 300
The texture curve is shown when a mastication test was performed using a rheometer after pressurizing at a pressure of 0 kg/cm2 for 5 minutes. h indicates hardness, and b/a indicates elasticity.

[Figure 2] Beef for 1000, 1500, 2000, 300
This is a graph showing the relationship between the degree of fragmentation of myofibrils observed under a phase contrast microscope after preparing myofibrils after applying pressure at a pressure of 0 kg/cm2 for 5 minutes, and the processing pressure.

Claims (1)

[Claims] [Claim 1] A lump of meat is placed in a flexible bag capable of withstanding high pressure, degassed and sealed, and then hydrostatic pressure is applied for a required period of time to soften the meat and promote ripening. A meat tenderization and aging method characterized by: