CN114391573A - A method to improve the meat color of DFD beef - Google Patents

Abstract

The invention relates to the technical field of meat processing, in particular to a method for improving the meat color of DFD beef, which comprises the steps of cutting the whole raw material meat (longissimus dorsi) into steaks, and then packaging the steaks in a high-oxygen modified atmosphere (60-80% O)₂+20％～30％CO₂+0％～10％N₂) And performing ice-temperature storage, wherein detection shows that the dark-color meat defect of the black cut beef can be effectively improved by combining high-oxygen conditioning packaging with the ice-temperature storage, so that the surface of the black cut beef is bright red of normal beef, the continuous pink phenomenon generated during the cooking of the black cut beef can be inhibited, the lipid oxidation degree of the black cut beef during the storage period can be obviously reduced, the growth of microorganisms is inhibited, and the shelf life of the product is prolonged. The method can be used for ensuring the acceptability of the fresh meat color during the sale and exhibition period of the black-cut beefsteak, improving the problem of continuous pink color during cooking, prolonging the shelf life of the product and having good application prospect.

Description

A method to improve the meat color of DFD beef

technical field

The invention relates to the field of meat packaging and preservation, in particular to a method for improving the meat color of DFD beef.

Background technique

Meat color is an important criterion for consumers to choose fresh meat. Black cut beef is flawed in both raw and cooked meat color. The limit pH value of black-cut beef is generally above 6.1, which is significantly higher than the normal pH value of normal beef (5.4-5.7), and its fresh meat is purple-red or dark purple. Due to these defects, it is often downgraded in the rating or directly listed out of the rating, and consumers are also less willing to buy this type of meat, which has caused a lot of economic losses. At the same time, due to the higher pH value, the heat sensitivity of myoglobin in the black cut meat is reduced, which leads to the persistent pink (Persisting pink, PP) phenomenon of the meat color when it is cooked, that is, the color that is not fully cooked at the end of heating, so that the Consumers mistakenly believe that the meat is undercooked and continue to heat it, which eventually leads to overcooking of the product, resulting in a decrease in the edible quality of the product. In addition, black-cut beef with high pH is more susceptible to microbial contamination due to the lack of nutrients such as glycogen and glucose, and has a shorter shelf life.

To avoid the formation of black cuts, the beef industry has been working to avoid or reduce the occurrence of black cuts. However, due to various reasons, the incidence of black cut beef in my country is still high. According to the survey by Zhao Qun (2013), the average incidence of black-cut beef in my country is as high as 10.1%, and the incidence of beef cattle production areas in the Northwest and Central Plains is even higher, reaching 17.70% and 23.61% respectively, which is significantly higher than the incidence of 4.89% in the Northeast region. Rate. In addition, according to Ming Dandan (2016) and other surveys, it was found that the incidence of black-cut beef in some companies in the southwest and central plains of my country is higher, sometimes as high as 65%. This has caused huge losses to my country's beef cattle industry.

Therefore, in view of the above problems, the development can not only improve the fresh meat color of black-cut beef, but also suppress the persistent pink problem during cooking, and prolong its shelf life, which is of great significance to the improvement of the profit of the beef cattle industry. However, at present, most of the common modified atmosphere packaging are developed for normal beef, and the pH value of black cut beef is high, the meat color rendering system is different from normal beef, and the high pH value leads to the growth of microorganisms during storage. in difference. Therefore, the modified atmosphere packaging that cannot black-cut beef cannot copy the packaging system of normal beef, and it is urgent to develop a packaging system suitable for black-cut beef. Therefore, this patent explores a packaging and storage method that improves the fresh and cooked meat color of DFD beef and prolongs its shelf life by optimizing the high oxygen-adjusted packaging with different oxygen concentrations combined with ice temperature conditions, which will greatly improve the commercial value of DFD beef and fully It is of great significance to give full play to its advantages of good tenderness and high water retention, while overcoming the disadvantage of meat color defects and increasing the benefits of the beef cattle industry.

SUMMARY OF THE INVENTION

Aiming at the flesh color problem of the black-cut beef, the present invention provides a method that can not only improve the fresh meat color of the black-cut beef, but also suppress the persistent pink phenomenon during cooking and prolong the shelf life of the product. The present invention adopts high-oxygen modified packaging with different oxygen concentrations combined with ice temperature conditions to develop a combined use scheme of modified atmosphere packaging and storage conditions for improving the color of black-cut beef, and provides data support for the optimization of the packaging method and storage temperature of black-cut beef. Simple and convenient, it greatly improves the intuitive fresh meat color of black-cut beef and the persistent pink phenomenon after cooking.

To achieve the above object, the present invention adopts the following technical solutions:

The invention provides a method for improving DFD beef meat color, comprising the following steps:

(1) After the raw meat is cut into pieces, put the steak into the tray packaging box for modified atmosphere packaging;

(2) the steak after packing is carried out the low temperature storage of different temperature;

(3) Open the package to directly observe or detect the color of the raw and fresh meat; cook the black-cut steak, and observe or measure the cooked meat color;

Further, in step (1), the raw meat is DFD beef, and the pH is 6.3-6.7; the average thickness of each steak is about 2.0-2.5cm, and the weight is 200-230g; there are three kinds of modified atmosphere packaging methods, and the gas groups are respectively : 60%～80%O ₂ +20%～30%CO ₂ +0%～10%N ₂ (enriched oxygen package), 50%～60%O ₂ +20%～30%CO ₂ +10%～ 30% N ₂ (medium oxygen modified packaging) and 20%~30% O ₂ +20% ~ 30% CO ₂ +40% ~ 60% N ₂ (low oxygen modified packaging).

Further, in step (2), the low-temperature storage includes two temperatures of ice temperature (-2～0°C) and cold storage (0～7°C).

Further, in step (3), the cooking temperature is 71-75° C., and the cooked meat color is the meat color of the cut surface after the steak is cut horizontally.

When the steak is cooked, the electric griddle is used for frying. When the central temperature of the steak is 71-75 °C, the cooking is completed, and the central temperature is detected in real time with a puncture thermometer.

The present invention investigates the influence of two storage temperatures combined with three different oxygen concentrations on modified atmosphere packaging on the fresh and cooked meat color of black-cut beef, and aims to develop a method that can improve both the fresh and cooked black-cut beef color. The combination of storage temperature and modified atmosphere packaging that can continue to pink phenomenon and can prolong the shelf life.

Beneficial effects of the present invention:

1. The oxymyoglobin ratio and oxygen penetration depth of black-cut beef are greatly increased through modified atmosphere packaging and ice-temperature storage of black-cut steak, and the fresh meat color of black-cut beef is improved, so that the surface meat color reaches normal. Level of beef flesh color.

2. The high oxygen-adjusted packaging combined with ice temperature storage not only effectively improves the raw and fresh meat color of the black-cut beef, but also effectively improves the persistent pink phenomenon when the black-cut beef is cooked, and avoids the food quality caused by over-cooking. reduce.

3. The high oxygen-adjusted packaging used in combination with ice-temperature storage also effectively inhibits the degree of lipid oxidation and the growth of microorganisms during the storage of black-cut beef, and significantly prolongs the shelf life.

4. The combination of high oxygen-adjusted packaging and ice temperature ensures the fresh meat color of black-cut beef during storage and the edible quality during cooking. The method can be simply and conveniently applied to actual operation and production, and can effectively avoid economic losses caused by the inferior meat color of black-cut beef.

Description of drawings

Figure 1: Surface color of black-cut beef with different treatments during storage

Figure 2: Effects of high oxygen modified packaging with different oxygen content and storage time on oxygen penetration depth (OPD) in black-cut steak ( ^ab : different letters indicate significant differences between different storage times under the same packaging condition (P<0.05); ^ln : different letters indicate significant difference between different storage methods for the same storage time (P<0.05); high oxygen modified packaging: 60%～80%O ₂ +20%～30%CO ₂ +0%～10%N ₂ ; Oxygen modified packaging: 50%～60%O ₂ +20%～30%CO ₂ +10%～30%N ₂ ;Low oxygen modified packaging: 20%～30%O ₂ +20%～30%CO ₂ +40% to 60% N ₂ ).

Figure 3: Effects of different storage temperatures and storage times on the fat oxidation value (TBARS) of black-cut steak ( ^ab : different letters indicate significant differences between different storage times under the same storage temperature condition (P<0.05); ^xy : different letters indicate There were significant differences between different storage temperatures at the same storage time (P<0.05))

Figure 4: Center color of cooked black cut beef with different treatments

Figure 5(a): The interaction between the high oxygen modified packaging method and storage time (a) the effect of the degree of myoglobin denaturation when the black-cut steak is cooked ( ^ac : different letters indicate different storage times (or storage time) under the same oxygen concentration The difference between different oxygen concentrations was significant (P<0.05); ^xz : different letters indicate that under the same storage time (or storage temperature) conditions, the difference between different oxygen concentrations was significant (P<0.05); high oxygen modified packaging: 60%～80 %O ₂ +20%～30%CO ₂ +0%～10%N ₂ ; Oxygen modified packaging: 50%～60%O ₂ +20%～30%CO ₂ +10%～30%N ₂ ;Low Oxygen modified packaging: 20%～30%O ₂ +20%～30%CO ₂ +40%～60%N ₂ )

Figure 5(b): The effect of the interaction between storage temperature and high oxygen modified packaging method on the degree of myoglobin denaturation when black-cut steak is cooked ( ^ac : different letters represent the difference between different storage times (or storage temperatures) under the same oxygen concentration There were significant differences between the two groups (P <0.05); ^xz : different letters indicate significant differences between different oxygen concentrations (P < 0.05) under the same storage time (or storage temperature) _; +20%～30%CO ₂ +0%～10%N ₂ ; Oxygen modified packaging: 50%～60%O ₂ +20%～30%CO ₂ +10%～30%N ₂ ; Hypoxic modified packaging : 20%～30%O ₂ +20%～30%CO ₂ +40%～60%N ₂ )

Figure 6(a): The effect of different oxygen concentrations on the total number of black-cut beef colonies during storage ( ^ab , different letters indicate significant differences at the same time, different oxygen concentrations (or storage temperatures), P <0.05; ^AC , different letters indicate the same oxygen concentration (or storage temperature) and different storage time have significant differences, P<0.05;

Figure 6(b): The effect of different storage temperatures on the total number of black-cut beef colonies during storage ( ^ab , different letters indicate significant differences at the same time, different oxygen concentrations (or storage temperatures), P <0.05; ^AC , different letters indicate the same oxygen concentration (or storage temperature) and different storage time had significant difference, P<0.05.

Detailed ways

Example 1

For the raw meat, the whole longissimus dorsi muscle with pH of 6.3 to 6.7 was used.

The preparation method includes the following steps:

(1) The raw meat is cut into steaks with a thickness of 2.5cm and a weight of 220g;

(2) The steaks in step (1) are randomly distributed into tray packaging boxes for modified atmosphere packaging. There are three types of modified atmosphere packaging, and the gas groups are: 60%~80%O ₂ +20%~30%CO ₂ +0%~10%N ₂ (high oxygen modified packaging), 50%~60%O ₂ +20%～30%CO ₂ +10%～30%N ₂ (medium oxygen regulated packaging) and 20%～30%O ₂ +20%～30%CO ₂ +40%～60%N ₂ (low oxygen regulated packaging) Package));

(3) The steak is stored at two temperatures, namely ice-temperature storage and low-temperature refrigeration, ice-temperature (-2～0℃), and refrigeration (0～7℃);

(4) The steak was stored at both temperatures for 0, 6 and 12 days;

(5) The color detection of fresh meat can be carried out directly by opening the package;

(6) Cooked meat color detection: Cook the steak to a central temperature of 72°C, cut the steak horizontally, use a colorimeter to detect the color of the cut surface, and conduct sensory evaluation of the meat color.

(7) The total number of colonies is sampled and detected after opening the package;

(8) The degree of lipid oxidation is sampled and detected after opening the package;

(9) The degree of myoglobin denaturation was sampled and detected when the beef was heated to the central temperature of 72°C.

According to the steak made in Example 1, the packaging at each time point was opened, the steak meat color index was directly measured, and samples were taken to detect the level of microorganisms and fat oxidation; after the steak was cooked, the meat color of the cut surface of the steak was observed, and sensory evaluation was carried out. Sampling and testing center The degree of denaturation of position myoglobin; the data were analyzed using the mixed model of SAS (MIXED procedure) for variance analysis, the significant level of difference was P<0.05, and the Sigmaplot12.5 software was used for graph analysis. The test results are shown in Tables 1-6 and Figures 1-6. Where L*, a*, b* represent the hue value, L* is the brightness, a* is the redness, b* is the yellowness, C is the color saturation value, H is the chapter value, MRA is the total reducing power, OC is the oxygen consumption rate, OPD is the oxygen penetration depth, and TBARS is the carbonyl value (characterizing the degree of fat oxidation).

Table 1 The effect of different packaging and storage time on the color of raw and fresh black-cut beef during the storage period

^ac marked with different letters in the same row means significant difference (P<0.05); ^xz marked with different letters in the same column means significant difference (P<0.05).

Table 2 Effects of storage temperature and storage time on a* and C values of black-cut beef

^ac Different letters in the same row indicate significant differences (P <0.05); different letters in the same column indicate significant differences (P < 0.05).

Table 3 Effects of different oxygen concentration packaging and storage time on the center color of black-cut beef after cooking

^ac : different letters in the same row indicate significant differences (P<0.05); ^yz : different letters in the same column indicate significant differences (P<0.05).

Table 4 The effect of different oxygen concentrations on the meat color score of DFD beef during the storage period

Different letters in ^ac indicate significant differences in oxygen concentration at the same storage time (P＜0.05)

Different letters of ^AC indicate significant differences in different storage times of the same oxygen concentration (P<0.05)

Cooked meat color score: 1 = very bright red; 2 = slightly bright red; 3 = pink; 4 = slightly pink; 5 = pinkish brown; 6 = tan; 7 = dark brown;

Degree of doneness score: 5 = well done; 4 = medium; 3 = medium; 2 = medium; 1 = medium

Analysis of Table 1 shows that the oxygen concentration and storage time in the high oxygen modified packaging have a significant interaction (P<0.05) on the L*, a*, b*, chroma, hue and R630/580 values. L*, a*, b*, chroma, hue and R630/580 in 20%O ₂ -MAP all showed an upward trend in the first 6 days of storage, but all showed a significant decrease after 6 days, which is characteristic of this packaging condition Although the meat color of black-cut beef improved in the early storage period, it decreased again after 6 days, and the redness value at 12 days was 13.15, which was lower than the critical value of 14.5 that consumers accepted for meat color, and the meat color stability was not enough. ideal. However, the black-cut steaks packaged with 50% O ₂ -MAP and 80% O ₂ -MAP showed a bright red meat color throughout the storage period, with higher L*, a*, b*, chroma and R630/580 value, lower hue value, and better meat color under 80% O ₂ -MAP package than 50% O ₂ -MAP within 6-12 days, indicating that both high oxygen modified packages have significantly improved The meat color of black cut beef, and 80% O ₂ -MAP works better. It can be seen from Table 2 that storage temperature and storage time also have significant interaction effects on a* value and chroma value (P<0.05). Compared with the initial value, the meat color under normal refrigeration and ice-temperature storage conditions was improved to a certain extent, and the ice-temperature storage had better meat color. This indicated that ice-temperature storage was more conducive to the improvement of meat color of black-cut beef.

Figure 1 shows that at 0d, the beef showed the typical dark purple color of DFD beef, but the high-oxygen modified packaging significantly improved the surface color of black cut meat during storage, making the surface appear bright red like normal beef, and the higher the oxygen concentration, the better the meat color. The better the effect. 20% O ₂ -MAP had a poor effect on improving meat color, while 50% O ₂ -MAP and 80% O ₂ -MAP had ideal effect on improving meat color of black cut meat. The improvement effect of ice temperature storage was better than that of 4 ℃ refrigeration. This is consistent with the data in Table 1. Based on the observation of this picture, the combination of ice-temperature storage + 80% O ₂ packaging has the best effect on meat color improvement, and modified atmosphere packaging with a concentration higher than 50% O ₂ can maintain a good intuitive meat color of DFD beef for more than 12 days.

Analysis of Figure 2 shows that under different packaging conditions, oxygen has a certain penetration depth in the black-cut steak, and a layer of oxygenated myoglobin is formed on the surface, while the non-penetrated interior is still typical of black-cut beef. of. The penetration of oxygen can make the deoxymyoglobin in the black cut meat combine with oxygen and convert it into oxymyoglobin to make the meat appear bright red and enhance the color of the black cut meat. The greater the penetration depth of oxygen, the deeper the oxymyoglobin layer. Figure 2 shows that oxygen concentration in packaging and storage time had a significant interaction (P<0.05) on oxygen penetration depth. As the oxygen concentration increases, the oxygen penetration depth gradually increases. The storage temperature had no significant effect on this index (P>0.05). Therefore, high oxygen concentration can enhance the surface color of black cuts, which corresponds to the picture in Figure 1.

Analysis of Figure 2 shows that storage time and storage temperature have interactive effects on lipid oxidation. With the prolongation of storage time, the TBARS values at both storage temperatures increased gradually, but the TBARS values at 4°C were higher. Oxygen concentration had no significant effect on TBARS value. This shows that with the prolongation of storage time, the degree of lipid oxidation increases gradually, but compared with conventional refrigeration at 4°C, ice-temperature storage can significantly reduce the degree of lipid oxidation.

Analysis of Table 3 shows that storage time has a significant effect on L*, a*, b*, chroma value and hue value. With the prolongation of storage time, the L* and hue values of the cooked black-cut steak gradually increased, while the a*, b* and chroma values gradually decreased. Similarly, the oxygen concentration in the package also has a significant effect on the a* value, chroma value and hue value. The redness value of the steak under the 80% O ₂ -MAP package is the lowest after cooking, which can greatly reduce the blackness value. Persistent pink coloration when cut beef is cooked. This is consistent with the picture shown in Figure 4.

Sensory evaluation was performed on the meat color of cooked black-cut steaks in different treatment groups, and the results are shown in Table 4. Storage time and oxygen concentration had significant effects on sensory redness value and degree of ripeness. With the prolongation of storage time, the sensory meat color score gradually increased, which indicated that with the prolongation of storage time, the redness of cooked meat color gradually decreased, the brown degree gradually deepened, and the sensory cooked degree also gradually increased. At the same time, with the increase of oxygen concentration in the package, the sensory meat color value gradually increased, and the sensory cooked score also gradually increased. This shows that with the prolongation of storage time, high-concentration oxygen modified atmosphere packaging can significantly inhibit the persistent pink phenomenon of black-cut beef when it is cooked, and return to the cooked meat color of normal beef.

Analysis of Fig. 5(a) shows that storage time and oxygen concentration have significant effects on the degree of myoglobin denaturation when black-cut beef is heated. With the prolongation of storage time, the degree of myoglobin degeneration showed an increasing trend, and with the increase of oxygen concentration, the degree of myoglobin degeneration increased significantly, and the ratio of myoglobin degeneration under 80% O ₂ -MAP packaging was the highest. Myoglobin undergoes thermal denaturation when heated, which can make the steak appear pink or brown after denaturation. The higher the degree of denaturation, the greater the degree of tan, and the greater the degree of sensory cooked. This is consistent with the results in Table 3, Table 4 and Figure 4. Figure 5(b) shows that storage temperature and oxygen concentration also have a significant effect on the degree of myoglobin denaturation. The greater the oxygen concentration in the packaging environment, the greater the thermal denaturation ratio of myoglobin.

Analysis of Figure 6 shows that the oxygen concentration in the packaging environment and the storage time have an interactive effect on the total number of colonies during the storage of black-cut steak (P<0.05). With the prolongation of storage time, the total number of colonies increased gradually, and 80% O ₂ -MAP and 50% O ₂ -MAP had a certain inhibitory effect on microorganisms at the later stage of storage. The initial colony count of black cut beef was 2.94log10 CFU/g, which was of good quality. After 12 days of storage, in the refrigeration group, the total number of colonies in the 80% O ₂ and 50% O ₂ packaging at the end of storage was about 5.5log10 CFU/g, but the 20% O ₂ packaging reached 6.64log10 CFU/g, which has reached deterioration. The standard of meat, it can be seen that 80% O ₂ -MAP and 50% O ₂ -MAP can inhibit the reproduction of microorganisms. At the same time, storage temperature and storage time also had an interactive effect on the total number of colonies during storage of black-cut steak (P<0.05). All packages in the ice temperature group did not exceed 4 log10 CFU/g throughout the storage period. Although the meat color of DFD beef packaged at ice temperature + 20% O ₂ was lower than the acceptable threshold for consumers at the 12th time, the total number of colonies was still in the range of second-grade fresh meat. In contrast, the total number of colonies under refrigerated conditions increased significantly at 12 days, approaching 6 log10 CFU/g. Therefore, high oxygen modified packaging combined with ice-temperature storage can well inhibit the growth of microorganisms during the storage of black-cut steak, and achieve the purpose of extending the shelf life.

Based on the above results, within 12 days of storage, 80% O ₂ packaging has the best color protection effect on the color of DFD beef. Combined with ice temperature conditions, it has good meat color stability, and the a* value during storage has been showing an upward trend. , and did not cause excessive oxidation of lipids. Changes in temperature more than different oxygen concentrations affected the meat color stability of DFD beef during storage. Untreated DFD beef undergoes a color change in the center from pink to bright red when cooked. Ice temperature combined with packaging with high oxygen concentration can significantly increase the depth of oxygen penetration to obtain a greater proportion of oxymyoglobin, increase the degree of myoglobin denaturation, and improve the persistent pink phenomenon of DFD beef. But the degree of improvement depends on the thickness of the steak and the depth of oxygen penetration.

Therefore, considering the color of raw and cooked meat, if DFD beef needs to be stored within 12 days, it is recommended to pack at ice temperature + 80% O ₂ to ensure the improvement of DFD beef raw and fresh meat color and cooked PP phenomenon. ₂₀ % O packaging is not recommended for DFD beef preservation. This experiment is to improve the quality of DFD beef through the combination of commonly used modified atmosphere packaging and ice temperature, which can be simply and conveniently applied to actual production.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims (1)

1. a method for improving DFD beef meat color is characterized in that comprising the following steps: S1. Cut steak: Cut DFD beef with a pH of 6.3-6.7 into steaks with a thickness of 2.0-2.5cm and a weight of 200-230g; S2. Modified atmosphere packaging: the steak obtained in step S1 is subjected to modified atmosphere packaging in a box, and the gas composition of the modified atmosphere packaging is 20%-80% O ₂ , 20%-30% CO ₂ , and 0%-60% N ₂ ; S3. Storage: the steak packaged in the modified atmosphere in step S2 is stored at -2 to 7°C.

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