Soluble gas stabilization pretreatment method for enhancing fresh-keeping effect of chilled beef

Abstract

The invention discloses a soluble gas stable pretreatment method for enhancing the fresh-keeping effect of chilled beef, and the SGS pretreatment method comprises the following steps: (1) in a constant-temperature closed chamber, beef blocks or beef steaks are placed on a net-shaped storage rack, the gap between the beef steaks or beef blocks is 5-10cm, and the vertical distance of the storage rack is greater than 20cm; (2) quantitative mixed gas mainly containing CO2 is filled into the constant-temperature closed chamber, the gas purity is 90%-100%, and the pressure is 0.1-0.3 MPa; (3) the temperature of the constant-temperature closed chamber is 1-5 DEG C; (4) performing constant-temperature and constant-pressure treatment for 1-24 hours; and (5) the interval between the pressure relief time and the packaging time is 10-20 minutes. According to the method, an SGS pretreatment technology and a packaging technology are combined, so that the defects of collapse of modified atmosphere packaging and blackening of vacuum skin packaging are overcome, the growth of pseudomonas and trichothecium thermocide is remarkably inhibited, the quality of the chilled beef is ensured, and the shelf life of the product is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to a soluble gas stabilization pretreatment method for enhancing the preservation effect of chilled fresh beef. Background Art

[0002] China is a major meat producer, and its meat output has ranked first in the world for many years. Since the 1990s, my country's beef industry has developed rapidly. With the improvement of residents' living standards, my country's per capita beef consumption has also increased rapidly, and beef has gradually become an important meat on consumers' tables.

[0003] At present, the main types of beef sold in the Chinese market are hot fresh beef, frozen beef and cold fresh beef. Hot fresh beef refers to beef that is sold directly on the market without any freezing and preservation treatment after slaughter. At present, hot fresh beef accounts for more than 60% of beef consumption. Since there is no complete low-temperature preservation treatment after slaughter, it provides conditions for the growth of microorganisms on the surface of meat, resulting in a very short shelf life and limited product radiation range. It must be eaten immediately, otherwise the safety of consumption cannot be guaranteed. When the handling and storage conditions are improper, it will bring huge food safety risks; frozen beef refers to beef that is directly pre-cooled after slaughter and then frozen at an ultra-low temperature environment, so that the internal temperature of the beef is controlled below -6°C. It accounts for only 30% of beef consumption. The color and taste of frozen beef are lower than those of hot fresh beef and cold fresh beef. Cold fresh beef, also known as chilled beef, is a kind of meat that is quickly cooled to 0-4°C after a professional slaughtering process. During the entire processing, circulation and sales process, the temperature is always strictly controlled between 0 and 4 degrees Celsius to ensure that the beef can be fully deacidified and post-ripened. This not only ensures the delicate texture and tender taste of the meat, but also ensures that its nutrients are retained to the greatest extent. Because of the low-temperature storage, cold fresh meat can effectively lock in moisture, keep fresh, and avoid changes in meat quality caused by high temperature. Due to its suitable storage temperature conditions, cold fresh beef maintains the original organizational structure and nutritional components of beef, making cold fresh beef rich in nutritional value, good quality, and conducive to human digestion and absorption.

[0004] The most concerning issue in the chilled meat industry is meat spoilage. The main cause of spoilage is the growth and reproduction of microorganisms on meat, followed by spoilage caused by oxidation of proteins and lipids. The production losses caused by spoilage can be as high as 40%.

[0005] At present, the packaging technologies that can effectively control spoilage include modified atmosphere packaging and vacuum skin packaging, but the CO2 in the modified atmosphere packaging can easily dissolve in the water and fat contained in the beef at low temperatures, reducing the gas concentration in the package and making the air pressure lower than the air pressure outside the package, causing the package to be squeezed and collapsed. Although vacuum packaging prolongs the shelf life of meat and meat products, the lack of oxygen forms deoxymyoglobin, causing the meat to turn black. The present invention is a pretreatment process that dissolves different types of gases into the product before packaging, which can avoid the problems of package collapse and meat turning black. However, the proportion, processing time, pressure, and amount of the gas are difficult to control accurately, and the impact of different processing parameters on the deterioration of various qualities of beef (such as fat oxidation and protein oxidation) is still unclear, which creates uncertainty for the use of this technology. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the problems of packaging collapse, blackening of meat color, etc. in the prior art, and to provide a soluble gas stabilization pretreatment method which can enhance the preservation effect of fresh cold beef before packaging.

[0007] The present invention adopts the following technical solutions to solve the above technical problems:

[0008] First aspect

[0009] The invention provides a soluble gas stabilization pretreatment method for enhancing the preservation effect of chilled fresh beef, which is characterized in that the beef is preserved by utilizing the soluble gas stabilization pretreatment method.

[0010] Preferably, the soluble gas stabilization pretreatment method comprises the following steps:

[0011] (1) Place the meat or steak flat on a mesh rack in a constant temperature sealed room;

[0012] (2) Filling a constant temperature closed chamber with a certain amount of mixed gas mainly composed of CO2 to maintain a constant pressure;

[0013] (3) Adjust the temperature of the constant temperature sealed chamber to be constant within a certain range;

[0014] (4) Treating at a constant temperature and pressure for a certain period of time;

[0015] (5) Packaging should be carried out within a certain period of time after pressure relief.

[0016] Preferably, the gaps between the beef chunks or steaks are 5-10 cm.

[0017] Preferably, the constant temperature sealed chamber is adjusted to 1-5°C.

[0018] Preferably, the pressure of the CO2 pretreatment is 0.1-0.3 MPa, preferably 0.2 MPa;

[0019] The CO2 pretreatment time is 1 to 24 hours.

[0020] Preferably, the constant temperature closed chamber also includes a sterilization operation;

[0021] Wherein, the sterilization includes sterilization by ultraviolet light irradiation. Preferably, the ultraviolet light irradiation sterilization time is 30-60 minutes.

[0022] Preferably, the beef is a steak with a thickness of 2 to 4 cm, preferably, the thickness of the steak is 2.45 cm, and the volume of the beef block is 2.5 cm 3 .

[0023] Preferably, the (3) is placed in a constant temperature sealed chamber, filled with a fixed amount of carbon dioxide gas and kept at a constant temperature and pressure, taken out after a certain period of treatment, and then vacuum or modified atmosphere packaging is performed, with the pressure release time and packaging time interval being 10 to 20 minutes.

[0024] Second aspect

[0025] The present invention has been found through research that the soluble gas pretreatment technology can dissolve the mixed gas mainly composed of CO2 into the product before packaging, thus avoiding the problem of collapse and blackening of meat color after product packaging. The soluble gas pretreatment technology can inhibit the growth of two dominant spoilage bacteria, Pseudomonas and Thermocyclone, during storage and delay protein oxidation through the antibacterial effect of the carbon dioxide mixed gas, and will not have a significant impact on volatile basic nitrogen and lipid oxidation, thereby extending the shelf life of the packaged beef and maintaining the food quality of the beef.

[0026] On the basis of being in accordance with the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present invention.

[0027] The reagents and raw materials used in the present invention are commercially available.

[0028] The positive and progressive effects of the present invention are: combining the soluble gas pretreatment method with packaging technology, especially vacuum skin packaging and modified atmosphere packaging, taking the dominant spoilage bacteria in vacuum skin packaging as the treatment target, clarifying the treatment gas component, temperature, time, and treatment pressure, overcoming the shortcomings of modified atmosphere packaging collapse and vacuum packaging meat color blackening, significantly inhibiting the growth of two dominant spoilage bacteria, Pseudomonas and Thermocyclone, during storage, and being able to delay protein oxidation of the product during storage, thereby extending the shelf life. It has a high application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention can be better understood by referring to the following description given in conjunction with the accompanying drawings. The accompanying drawings, together with the following detailed description, are included in this specification and form a part of this specification, and are used to further illustrate the preferred embodiments of the present invention and explain the principles and advantages of the present invention.

[0030] Figure 1 The effect of SGS pretreatment on the total bacterial count of fresh beef during storage. DETAILED DESCRIPTION

[0031] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples. The experimental methods in the following examples without specifying specific conditions are carried out according to conventional methods and conditions, or selected according to the product specifications.

[0032] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0033] The beef in the following examples was sourced from a certain Muslim meat company in Binzhou City, Shandong Province, and Simmental crossbred cattle (similar in size, 20 to 24 months old, bulls) were selected as experimental sample objects.

[0034] The vacuum skin packaging machine in the following embodiments was purchased from Dajiang Machinery Equipment Co., Ltd.

[0035] Example 1

[0036] (1) After being irradiated with ultraviolet light for 40 minutes, the beef collected from the factory was cut into pieces with a thickness of 2.5 cm in three constant temperature closed rooms. 3 Place the beef chunks (several) flat on the mesh rack, with a gap of 8cm between the beef chunks or steaks, and adjust the upper and lower spacing of the rack to 30cm;

[0037] (2) A certain amount of CO2 gas with a purity of 98% was charged into three constant temperature closed chambers respectively; the pressure of the first experiment group was not pressurized, the pressure of the second experiment group was controlled at 0.2 MPa, and the pressure of the third experiment group was controlled at 0.2 MPa;

[0038] (3) Adjust the temperature of three thermostatically sealed rooms to 4°C;

[0039] (4) The constant temperature and pressure treatment time for the first experiment group was 24 h, the constant temperature and pressure treatment time for the second experiment group was 3 h, and the constant temperature and pressure treatment time for the third experiment group was 24 h;

[0040] (5) The control group was directly vacuum-packed without any treatment, while the experimental group completed vacuum-packing within 20 minutes of decompression.

[0041] (6) After completing the vacuum skin packaging, the product was quickly stored at 4°C, with the day of soluble gas stabilization treatment as day 0. Microbiological and physical and chemical indicators were measured on days 0, 10, 20, 30, and 40 of storage.

[0042] Example 2

[0043] (1) After being irradiated with ultraviolet light for 40 minutes, the beef collected from the factory was cut into pieces with a thickness of 2.5 cm in three constant temperature closed rooms. 3 Place the beef chunks (several) flat on the mesh rack, with a gap of 8 cm between the beef chunks or steaks, and adjust the upper and lower spacing of the rack to 30 cm;

[0044] (2) A certain amount of CO2 gas with a purity of 98% is charged into three constant temperature sealed chambers respectively; the pressure is controlled at 0.2 MPa;

[0045] (3) Adjust the temperature of three thermostatically sealed rooms to 4°C;

[0046] (4) The constant temperature and pressure treatment time for the first experiment group was 24 h, the constant temperature and pressure treatment time for the second experiment group was 3 h, and the constant temperature and pressure treatment time for the third experiment group was 24 h;

[0047] (5) The control group was directly vacuum-packed without any treatment, while the experimental group completed vacuum-packing within 20 minutes of decompression.

[0048] (6) After completing the vacuum skin packaging, the product was quickly stored at 4°C, with the day of soluble gas stabilization treatment as day 0. Microbiological and physical and chemical indicators were measured on days 0, 10, 20, 30, and 40 of storage.

[0049] Example 3

[0050] (1) After being irradiated with ultraviolet light for 40 minutes, the beef collected from the factory was cut into pieces with a thickness of 2.5 cm in three constant temperature closed rooms. 3 Place the beef chunks (several) flat on the mesh rack, with a gap of 8 cm between the beef chunks or steaks, and adjust the upper and lower spacing of the rack to 30 cm;

[0051] (2) A certain amount of CO2 gas with a purity of 98% is charged into three constant temperature sealed chambers respectively; the pressure is controlled at 0.2 MPa;

[0052] (3) Adjust the temperature of three thermostatically sealed rooms to 4°C;

[0053] (4) The constant temperature and pressure treatment time is 24 hours;

[0054] (5) The control group was directly vacuum-packed without any treatment, while the experimental group completed vacuum-packing within 20 minutes of decompression.

[0055] (6) After completing the vacuum skin packaging, the product was quickly stored at 4°C, with the day of soluble gas stabilization treatment as day 0. Microbiological and physical and chemical indicators were measured on days 0, 10, 20, 30, and 40 of storage.

[0056] Effect Example 1

[0057] The most important reason for meat spoilage is the corruption on the surface and inside of the meat and the growth and reproduction of pathogens. During the slaughtering process of beef cattle, the beef cattle themselves and their meat will inevitably come into contact with the external environment, making them susceptible to contamination from external microorganisms. Especially those cold-loving microorganisms that live in low temperatures, they can not only survive, but also continue their normal physiological functions. These microorganisms can decompose proteins and other important nutrients in the meat, thus causing serious contamination to the fresh meat. In order to maintain the quality of meat products and extend the shelf life, effective measures must be taken to control and prevent the growth of these harmful microorganisms.

[0058] In the spoilage process of chilled meat, oxidation of fat and protein is an important factor that cannot be ignored. This process mainly involves the oxidative stress state experienced by livestock and poultry after slaughter, and the early free radical attack suffered by lipids and muscle proteins during storage, and may also have adverse effects on the appearance and color of meat. They may cause the meat to darken, uneven color, and even in some cases, lose its original luster, which are important factors that consumers need to consider when purchasing.

[0059] Open the vacuum skin package under sterile conditions, use sterilized tools to take 10g of meat sample from the surface of beef and quickly put it into a sterile beating bag (BagPageR; Interscience, St Nom, France), add 90mL of sodium chloride solution (containing 0.1% peptone) and then put it into a beating machine and beat for 90s. Take 1mL of bacterial solution and perform 10-fold gradient dilution in sequence, select the dilution gradient according to the growth of various bacteria, then spread the bacterial solution or dilution liquid on the culture dish and pour different selective culture media, and make two or three parallels for each dilution gradient.

[0060] Table 1 Effect of SGS pretreatment on the number of heat-killed circinellae in fresh beef during storage

[0061]

[0062] Depend on Figure 1It can be seen that after 30 days, the total number of colonies in the control group beef was significantly higher than that in the three types of SGS pretreated fresh beef. The total number of colonies in the control group beef reached 6.59 lg CFU / g after 40 days of storage, exceeding the national standard limit for fresh meat (1×10 6 CFU / g), while at 40 days, the total colony counts of the two pressurized SGS pretreatments for 1-3h and 3-24h were 4.69 and 4.29lg CFU / g, respectively, both below 5lg CFU / g, and significantly decreased by 1.9 and 2.3lg CFU / g, respectively, compared with the control group. However, compared with the non-pressurized SGS pretreatment for 24h, the 0.2MPa 1℃ SGS pretreatment for 1-3h had a better antibacterial effect. Even though the pressurized SGS pretreatment for 3-24h had a better antibacterial effect, it was only 0.4lg CFU / g different from the pressurized SGS pretreatment for 3h. Considering the time factor, 0.2MPa 1℃ SGS pretreatment for 1-3h was more preferred.

[0063] As can be seen from Table 1, the competitive ability of the heat-killed cyclothripsis in the vacuum skin packaging was weak in the first 20 days, and its growth was inhibited. However, it began to multiply in large quantities from the 30th day. During its reproduction, the deeper the SGS treatment, the better the antibacterial effect on the heat-killed cyclothripsis. For example, the number of heat-killed cyclothripsis treated with pressurized SGS for 3-24 hours was only 2.09lg CFU / g, which was significantly reduced by 3.24lg CFU / g compared with the control group, while the number of heat-killed cyclothripsis treated with pressurized SGS for 1-3 hours was significantly reduced by 2.35lg CFU / g compared with the control group. Both pressurized SGS treatments have significant effects on inhibiting heat-killed cyclothripsis, so considering the time factor, 0.2MPa 1℃ SGS pretreatment for 1-3 hours is the best treatment method.

[0064] Table 2 Effect of SGS pretreatment on the number of Pseudomonas in fresh beef during storage

[0065]

[0066] As shown in Table 2, the growth trend of Pseudomonas in each group during storage is the same as that of the heat-killed cyclotrichum at each storage time point. Pseudomonas was not detected in the early stage of storage, and the number of Pseudomonas detected in the control group at the end of storage for 40 days was as high as 6.19lg CFU / g. Although the presence of Pseudomonas was also detected in the other three experimental groups, their values ​​were kept at a lower level, which were 2.71, 2.59, and 1.70lg CFU / g respectively compared with the control group. Among them, the number of Pseudomonas in beef pretreated with 0.2MPa 1℃ SGS for 1-3 and 3-24 hours was significantly reduced by 3.60 and 4.49lg CFU / g respectively compared with the control group, and the number of Pseudomonas in beef treated with pressurized SGS for 24 hours was below 2lg CFU / g, indicating that each SGS pretreatment can inhibit the growth of Pseudomonas.

[0067] Effect Example 2

[0068] 1. SGS pretreatment will not affect the volatile basic nitrogen of fresh beef during storage

[0069] According to the national standard GB 5009.228-2016 "National Food Safety Standard Determination of Volatile Basic Nitrogen in Food", an automatic Kjeldahl nitrogen analyzer is used for determination. Prepare the required boric acid solution (20g / L), hydrochloric acid solution (0.01mol / L) and pure water (pure water instrument) in advance and connect them to the fully automatic Kjeldahl nitrogen analyzer. Then weigh 10g of meat sample (remove fat tendons), chop it, put it into a conical flask, add 75mL of pure water, stir with a glass rod, and let it stand for 30 minutes, then filter and transfer to a clean distillation tube, add 1g of magnesium oxide, and connect to the instrument for distillation.

[0070] Volatile basic nitrogen content in meat samples:

[0071]

[0072] Wherein, X is the content of volatile basic nitrogen; c is the concentration of hydrochloric acid; V1 is the volume of hydrochloric acid consumed in the titration to the endpoint; V2 is the volume of the hydrochloric acid standard solution consumed in the blank control test; 14 is the mass of nitrogen equivalent to the titration of 1.0mL of hydrochloric acid (cHCl=1.000mol / L) standard titration solution, in grams per mole (g / mol); 100 is the conversion factor for converting the calculated result to milligrams per hundred grams (mg / 100g).

[0073] Table 3 Effect of SGS pretreatment on volatile basic nitrogen value of fresh beef during storage

[0074]

[0075] As shown in Table 3, whether the beef was directly vacuum-packed without pretreatment or vacuum-packed after SGS pretreatment, the volatile basic nitrogen content of each group showed an upward trend with the extension of storage time. And the volatile basic nitrogen content of each group did not exceed the limit standard of 15mg / 100g specified in GB2707-2016, which shows that SGS pretreatment will not significantly affect the volatile basic nitrogen content of fresh beef.

[0076] Effect Example 3

[0077] SGS pretreatment does not affect lipid oxidation in fresh beef during storage

[0078] Lipid oxidation was assessed in triplicate by the TBARS method of Kim et al. (2015) with modifications. Results are presented as milligrams of malondialdehyde (MDA) per kg of packaged beef sample (Kim et al., 2015). Rancid odors are detected if TBARS values ​​are above 0.5 mg MA / kg (Sheard et al., 2000; Choi et al., 2011).

[0079] Table 4 Effect of SGS pretreatment on lipid oxidation of fresh beef during storage

[0080]

[0081] It can be seen from Table 4 that after SGS pretreatment, there is no significant difference in the TBARS value of fresh beef and the TBARS value of the control group that has not been pretreated, indicating that SGS pretreatment has no significant effect on the TBARS value of fresh beef.

[0082] Effect Example 4

[0083] Effect of SGS pretreatment on oxidation of fresh beef protein during storage

[0084] Take a clean cutting board and knife, take 0.5g beef sample, mince it, remove the fat tendon and put it into a 5mL cryotube, add 5mL 20mM phosphate buffer, put it into a grinder at 4℃, grind it at 50Hz for 45s, take a break for 15s, and grind it for 15s three times. Transfer the homogenate to a 10mL centrifuge tube and centrifuge it at 5000×g for 20min at 4℃. The supernatant after centrifugation is the protein solution.

[0085] (1) Carbonyl content

[0086] The carbonyl content was determined by referring to the experimental method of Soyer et al. (2010) and slightly modified. Three 30μl protein solutions were taken in 2mL centrifuge tubes. Two of the experimental groups were added with 1mL of 10mM DNPH solution, and one of the control groups was added with 1mL of 2M HCl. After vortexing, the mixture was placed in a 37℃ incubator in the dark for 1h. After the incubation, 0.5mL of 20% TCA solution was added to each of the three groups to precipitate the protein. After mixing, the mixture was placed at 4℃ and centrifuged at 10000×g for 10min. The supernatant was discarded and the precipitate was retained. 1mL of a mixed solution of ethanol and ethyl acetate (ethanol: ethyl acetate = 1:1) was added to the protein precipitate, and the mixture was washed and centrifuged at 4℃ and 12000×g for 10min. The washing was repeated three times until the supernatant was clear. After washing, add 1.5 mL of guanidine hydrochloride to the precipitate to dissolve the precipitate, vortex mix until the precipitate is completely dissolved and there is no floc, transfer 250 μl of the mixture to a 96-well plate, measure the absorbance at 370 nm, and calculate according to the Lambert-Beer law. The result is expressed as the amount of carbonyl substance per gram of meat sample.

[0087] Table 5 (A) Effect of SGS pretreatment on carbonyl content of fresh beef during storage

[0088]

[0089] As shown in Table 5(A), the carbonyl content of beef pretreated with SGS is relatively higher than that of the control group, which means that the degree of protein oxidation is also higher than that of the control group. Overall, the carbonyl content of beef in the experimental group pretreated with 0.2MPa1℃SGS for 1-3h is significantly lower or not significantly higher than that of other groups, which has a good effect on maintaining a low carbonyl content and delaying protein oxidation.

[0090] (2) Total thiol content

[0091] The method for determining total thiol groups was slightly modified from the method of Fu et al. (2015). 0.1 mL of the myofibrillar protein solution extracted in 2.4.6 was taken into a 2 mL centrifuge tube, and 0.9 mL of 50 mM phosphate buffer containing urea and 0.04 mL of DTNB solution were added. After mixing evenly, the mixture was placed in a 37 °C incubator in the dark for 30 min. After the incubation, the mixture was transferred to a 96-well plate with a pipette and its absorbance was measured at 412 nm. The total thiol content was calculated according to the Lambert-Beer law with a molar absorption coefficient of 13600 M-1 cm-1. The result was expressed as the amount of total thiol substances per gram of sample.

[0092] Table 5 (B) Effect of SGS pretreatment on total sulfhydryl content of fresh beef during storage

[0093]

[0094] As shown in Table 5(B), the total thiol content of each group decreased with the extension of storage time. The total thiol content of the three experimental groups pretreated with SGS was relatively higher than that of the control group, but the difference was not large.

[0095] Effect Example 5

[0096] The beef cut in a sterile environment is weighed before SGS pretreatment, and the weight of each piece of beef is recorded as M0 (g). After SGS pretreatment, the beef is vacuum-packed. At each storage time point, the beef is taken out in a sterile environment and weighed. At this time, the weight of each piece of beef is recorded as M (g). The calculation formula for storage loss is as follows:

[0097]

[0098] Table 6 Effect of SGS pretreatment on storage loss rate of fresh beef during storage

[0099]

[0100] As shown in Table 6, the storage loss rate of beef pretreated with SGS for 24 hours without pressure and 1-3 hours with pressure was very small compared with the control group. Only the storage loss rate of beef pretreated with SGS for 3-24 hours was significantly higher than that of the other two CO2 treatment groups, reaching 3%. In general, beef pretreated with 0.2MPa SGS for 1-3 hours can avoid serious storage loss under the condition of shorter pretreatment.

[0101] Effect Example 6

[0102] At each sampling storage time point, the package was opened in a relatively sterile environment, and the beef was placed on an iron plate at 3±1℃ for 30 minutes to develop color. The brightness (L*), redness (a*), yellowness (b*), saturation (C*) and hue angle (h*) of the beef surface were recorded. Six points were randomly selected from each part of each piece of beef for measurement, and the average value was finally taken. While measuring the color of fresh meat, the reflectance at 580nm and 630nm wavelengths was measured with a pH meter, and the ratio of the two was calculated to obtain the R630 / 580 value.

[0103] Table 7 (A) Effect of SGS pretreatment on a* value of fresh beef during storage

[0104]

[0105]

[0106] As shown in Table 7(A), the a* value of the SGS24h (0.2MPa) treatment group was significantly reduced. However, subsequent studies found that although the a* value was significantly reduced after SGS pretreatment and packaging, the beef color would not deteriorate. Overall, the 0.2MPa 1℃ SGS pretreatment for 3 hours group had a better effect on maintaining the redness value of the fresh beef, and would not produce unacceptable results.

[0107] Table 7 (B) Effect of SGS pretreatment on h* value of fresh beef during storage

[0108]

[0109]

[0110] As shown in Table 7 (B), with the deepening of SGS pretreatment, the h* value of fresh beef increases continuously. After pretreatment, the h* value of the experimental group pretreated with SGS is higher than that of the control group. In general, the h* value of beef pretreated with 0.2MPa SGS for 3h is higher than that of the control group, but it is relatively lower than that of the other three treatment groups, and the fading rate is also relatively slow.

[0111] Table 7 (C) Effect of SGS pretreatment on R630 / 580 value of fresh beef during storage

[0112]

[0113] It can be seen from Table 7 (C) that as the degree of carbon dioxide gas dissolved in beef during SGS pretreatment increases, the R630 / 580 value of fresh beef continues to increase. The measurement of the R630 / 580 value after pretreatment found that the R630 / 580 value of fresh beef in the experimental group pretreated with SGS was higher than that in the control group, and the R630 / 580 values ​​of fresh beef in each group continued to decrease with the extension of storage time.

[0114] Table 7 (D) Effect of SGS pretreatment on L* value of fresh beef during storage

[0115]

[0116]

[0117] As shown in Table 7 (D), the L* value of the experimental group pretreated with SGS is higher than that of the control group at any storage time point. Overall, the L* value of the cold fresh beef in the experimental group pretreated with 0.2MPa 1℃ SGS for 3 hours is significantly higher or not significantly lower than that of the control group and other experimental groups during storage, and the brightness is better maintained. As shown in Table 7 (E), the b* value does not change with the degree of SGS pretreatment, indicating that SGS pretreatment does not cause the b* value of cold fresh beef to change.

[0118] Table 7 (E) Effect of SGS pretreatment on b* value of fresh beef during storage

[0119]

[0120] As shown in Table 7(E), the b* value did not change with the degree of SGS pretreatment, indicating that SGS pretreatment did not cause the b* value of fresh beef to change.

[0121] In summary, the SGS pretreatment technology is combined with vacuum skin packaging, and the dominant spoilage bacteria in vacuum skin packaging are targeted for treatment. The effect of the combined use of the two preservation technologies on the preservation of fresh beef and extending the shelf life is explored. SGS pretreatment for 3 hours under 0.2MPa 1℃ conditions can effectively inhibit the growth of microorganisms while ensuring the quality of beef, and help improve production efficiency, which has good application prospects.

[0122] Finally, it should be noted that in the present invention, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements that are inherent to such process, method, article or apparatus.

[0123] Although the present invention has been disclosed above by the description of the specific embodiments of the present invention, it should be understood that those skilled in the art can design various modifications, improvements or equivalents of the present invention within the spirit and scope of the attached scheme. These modifications, improvements or equivalents should also be considered to be included in the scope of protection claimed by the present invention.

Claims

1. A soluble gas stabilization pretreatment method for enhancing the preservation effect of fresh beef, characterized in that: Before controlled atmosphere and vacuum packaging, the beef was preserved using the SGS pretreatment method.

2. The soluble gas stabilization pretreatment method for enhancing the preservation effect of fresh beef according to claim 1, characterized in that: The SGS pretreatment method comprises the following steps: (1) Place the meat or steak flat on a mesh rack in a constant temperature sealed room; (2) Fill the constant temperature sealed chamber with CO2 gas to maintain a constant pressure; (3) Adjust the temperature of the constant temperature closed chamber; (4) Constant temperature and pressure treatment; (5) Packaging after pressure relief.

3. The soluble gas stabilization pretreatment method for enhancing the preservation effect of fresh beef according to claim 2, characterized in that: The constant temperature sealed chamber is adjusted to 1-5°C.

4. The soluble gas stabilization pretreatment method for enhancing the preservation effect of fresh beef according to claim 2, characterized in that: The soluble gas stabilization pretreatment method for the preservation effect of strong cold fresh beef meets at least one of the following conditions: In step (2), the pressure of the CO2 mixed gas pretreatment is 0.1-0.3 MPa, preferably 0.2 MPa; The CO2 pretreatment time is 1 to 24 hours; In step (3), the temperature of the constant temperature sealed chamber is 2-6°C, preferably 4°C.

5. The soluble gas stabilization pretreatment method for enhancing the preservation effect of fresh beef as described in claims 2 to 4, characterized in that: The constant temperature closed chamber also includes a sterilization operation; Wherein, the sterilization includes sterilization by ultraviolet light irradiation. Preferably, the ultraviolet light irradiation sterilization time is 30-60 minutes.

6. The soluble gas stabilization pretreatment method for enhancing the preservation effect of fresh beef as described in claims 2 to 5, characterized in that: The beef is a steak or beef block with a thickness of 2 to 4 cm. Preferably, the thickness of the steak is 2.45 cm, and the volume of the beef block is 2.5 cm. 3 .

7. The soluble gas stabilization pretreatment method for enhancing the preservation effect of fresh beef according to claim 2, characterized in that: The gaps between the steaks or beef blocks are 5-10 cm, and the upper and lower spacings are greater than 20 cm.

8. The soluble gas stabilization pretreatment method for enhancing the preservation effect of fresh beef according to claim 2, characterized in that: The (5) step is to place the treated product into a constant temperature sealed chamber, fill it with a fixed amount of carbon dioxide gas and keep the temperature and pressure constant, take it out after a certain period of treatment, and then perform vacuum or modified atmosphere packaging, with the pressure release time and packaging time interval being no more than 20 minutes.

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