Cooked meat product vacuum precooling and vacuum packaging integrated method and equipment and application thereof

Abstract

The invention relates to a vacuum precooling and vacuum packaging integrated method for cooked meat products, which comprises the following steps: putting the cooked meat products into a packaging bag for prepackaging, then sterilizing, putting the sterilized cooked meat products into a vacuum box, and putting the packaging bag into an ice-water mixture; closing the vacuum box, starting a vacuum pump to vacuumize, sealing the packaging bag after the temperature of the cooked meat product is reduced to a preset temperature, closing the vacuum pump, and recovering normal pressure to obtain the pre-cooled cooked meat product. The ice-water mixture is used as a cooling auxiliary carrier and cooperates with vacuum pre-cooling to complete cooling of the sample, after pre-cooling is completed, the cooked meat product does not need to be removed out of a vacuum box for vacuum packaging, a re-pressing process is avoided, and the risk of secondary pollution is avoided. The invention further provides equipment of the vacuum precooling and vacuum packaging integrated method, and the vacuum precooling and vacuum packaging integrated method for the cooked meat products is suitable for treating livestock and poultry meat products, especially chicken and pork.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, and in particular to an integrated method, equipment and application for vacuum precooling and vacuum packaging of cooked meat products. Background Technology

[0002] Vacuum precooling primarily works by reducing the pressure of the material's environment to induce the evaporation of free water within the material. The significant latent heat required for water evaporation originates from the material itself, thus achieving rapid cooling. Therefore, a certain degree of porosity and sufficient free water content in the material are crucial conditions for successful vacuum precooling. However, this cooling method, which relies on water evaporation to remove heat, inevitably leads to the loss of some moisture from the material. Since most commodities are traded by weight, moisture loss often reduces the material's weight, thereby affecting its commercial value.

[0003] Currently, methods to improve moisture loss during vacuum precooling of cooked meat products mainly focus on the following three aspects: One approach is to use a combination of precooling methods. Common combinations include vacuum precooling followed by air cooling, air cooling followed by vacuum precooling, vacuum precooling followed by immersion vacuum precooling, and immersion vacuum precooling followed by vacuum precooling. While these methods can achieve a good balance between precooling rate and moisture loss, they cannot ensure continuous sample precooling.

[0004] Secondly, a combination of impregnation vacuum precooling and vacuum precooling under continuous operation is adopted. Although this method can effectively combine the advantages of impregnation vacuum precooling and vacuum precooling and solve the problem of operational inconsistency, its cooling rate is still lower than that of vacuum precooling alone. Furthermore, the samples treated in this way may still be at risk of "secondary contamination" during the repressurization (the process of the vacuum chamber returning to atmospheric pressure) or vacuum packaging (removing the sample from the vacuum chamber and then vacuum packaging it).

[0005] Third, cryogenic devices assist in vacuum precooling. Although this method can achieve a cooling rate close to or even better than vacuum precooling, and with lower moisture loss, samples treated in this way may still be at risk of "secondary contamination" during the repressurization or vacuum packaging process.

[0006] Therefore, achieving rapid cooling rates while minimizing moisture loss, and avoiding potential "secondary contamination" during repressurization or vacuum packaging, remains a pressing challenge that needs to be addressed. Summary of the Invention

[0007] Based on this, the purpose of the present invention is to provide a method and application for integrating vacuum precooling and vacuum packaging of cooked meat products, which takes into account both cooling rate and moisture loss rate, while also avoiding the risk of "secondary contamination".

[0008] First aspect: A method for integrating vacuum precooling and vacuum packaging of cooked meat products includes the following steps: The cooked meat products are pre-packaged in packaging bags, then sterilized, and then placed in a vacuum chamber. The packaging bags are then placed in an ice-water mixture. The vacuum chamber is closed, the vacuum pump is started to create a vacuum, and once the temperature of the cooked meat products drops to a preset temperature, the packaging bags are sealed, the vacuum pump is turned off, and the pressure is restored to normal to obtain pre-cooled cooked meat products.

[0009] This invention uses an ice-water mixture as a cooling auxiliary carrier, which works in conjunction with vacuum precooling to cool the sample. After precooling, the cooked meat products do not need to be removed from the vacuum box for vacuum packaging, and there is no repressurization process, thus avoiding the risk of "secondary contamination".

[0010] As a preferred embodiment, the method further includes the following steps: turning on the ultraviolet lamp after closing the vacuum chamber, and turning off the ultraviolet lamp after turning off the vacuum pump. The cooked meat products are further sterilized by irradiating them with the ultraviolet lamp during the cooling process.

[0011] As a preferred embodiment, the following steps are also included: after the cooked meat product is placed in the packaging bag, it is sterilized in steam for 1-2 minutes, and the steam temperature is 90~100℃.

[0012] As a preferred embodiment, the method further includes the step of completely submerging the cooked meat product in the ice-water mixture. Complete submersion of the cooked meat product in the ice-water mixture not only ensures more even cooling but also prevents excessive localized moisture loss.

[0013] As a preferred embodiment, the temperature of the ice-water mixture is 0~4℃. Precooling at this temperature can balance the precooling rate and the moisture loss rate.

[0014] As a preferred option, when the vacuum chamber is evacuated, the pressure drop rate coefficient is given by the formula... Determined; among them, P This represents the absolute pressure inside the vacuum chamber during operation, expressed in Pa. P i The local atmospheric pressure is expressed in Pa; t is the time the vacuum pump pumps air into the vacuum chamber, expressed in min. Y This is the rate of pressure decrease, in minutes. -1 The pressure drop rate is 0.2-0.6 min. -1By properly controlling the rate of pressure drop, not only can a cooling rate close to that of individual vacuum precooling be obtained, but the moisture loss rate can also be controlled within 3-5%, approaching the moisture loss of air cooling.

[0015] As a preferred embodiment, the packaging bag includes a foil-lined packaging bag.

[0016] The second aspect: An integrated vacuum precooling and vacuum packaging device for cooked meat products as described in the first aspect includes a vacuum precooling machine, a sealing device, and a low-temperature auxiliary device; The vacuum precooling machine includes a vacuum chamber, a vacuum pump, a refrigeration system, sensors, and a control system. The refrigeration system is used to condense the water vapor generated in the vacuum chamber during the vacuum precooling process. The sensors include a temperature sensor and a pressure sensor. The control system is used to control the opening and closing of the vacuum pump and the refrigeration system. The sealing device includes an air compressor, a cylinder, a sealer, and a solenoid valve. The sealer is connected to the cylinder, and the opening and closing of the sealer is controlled by the extension and retraction of the cylinder. The cylinder is also connected to the solenoid valve and communicates with the air compressor. The extension and retraction of the cylinder is controlled by the on / off state of the solenoid valve, and the extension and retraction of the cylinder is accomplished by the compressed air generated by the air compressor. The low-temperature auxiliary device is used to contain the cooked meat product and the ice-water mixture; The refrigeration system, sensors, cylinders, sealers, and cryogenic auxiliary devices are located inside the vacuum chamber, while the control system, air compressor, and solenoid valve are located outside the vacuum chamber. The vacuum pump is located outside the vacuum chamber and is connected to the vacuum chamber.

[0017] Third aspect: The application of the integrated vacuum precooling and vacuum packaging method for cooked meat products described in the first aspect is suitable for processing livestock and poultry meat products, such as chicken and pork. Attached Figure Description

[0018] Figure 1 A schematic diagram of the overall structure of an integrated vacuum precooling and vacuum packaging equipment for cooked meat products; Among them, 11-vacuum chamber, 21-cylinder, 22-sealer, 23-power switch, 24-solenoid valve, 3-low temperature auxiliary device, 4-compressed air inlet direction. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] A method for integrating vacuum precooling and vacuum packaging of cooked meat products includes the following steps: S1: Heat the sealer inside the vacuum chamber to the preset temperature, turn on the ultraviolet lamp inside the vacuum chamber, and close the vacuum chamber door.

[0021] S2: Pre-package cooked meat products in sterilized packaging bags, then put them in a steamer and steam at 90~100℃ for 1-2 minutes to sterilize them.

[0022] S3: Turn off the ultraviolet lamp in the vacuum chamber, put the steam-cooked packaging bag into the vacuum chamber and fix it, immerse the cooked meat product in a 0~4℃ ice water mixture, and put the bag opening into the sealing device.

[0023] S4: Close the vacuum chamber door and turn on the ultraviolet lamp; turn on the vacuum pump, adjust the pressure drop rate, and turn on the evaporator at the same time until the temperature of the cooked meat products drops to the preset temperature; before repressurization, use a sealer to seal the packaging bag to complete the sealing of the packaging bag.

[0024] S5: Turn off the vacuum pump, evaporator and ultraviolet lamp, wait for the vacuum chamber to return to normal pressure, and then open the drain valve to remove the condensate.

[0025] S6: Take out the vacuum-packed cooked meat products, calculate the pre-cooling time and moisture loss rate, and conduct a sensory evaluation of the pre-cooled cooked meat products.

[0026] In this embodiment of the invention, the steam cooking temperature is 100°C, the temperature of the ice-water mixture is 4°C, and the packaging bag is a tin foil packaging bag.

[0027] It should be noted that the pressure drop rate coefficient used in this invention is derived from the formula... Confirmed. Among them, P This represents the absolute pressure inside the vacuum chamber during operation, expressed in Pa. P i t represents the local atmospheric pressure, in Pa; t represents the time the vacuum pump pumps the vacuum chamber, in min. Y This is the rate of pressure decrease, in minutes. -1 The rate of pressure decrease is calculated using the time t taken for the local atmospheric pressure to drop from 100,000 Pa to an absolute pressure of 650 Pa. Y Value. Pressure drop rate coefficient. YThe pressure drop rate coefficient indicates the rate at which pressure decreases. A larger coefficient means a faster rate of pressure decrease and a shorter time. Conversely, a smaller coefficient means a slower rate of pressure decrease and a longer time. For example, if the time it takes for the pressure to drop from 100,000 Pa to 650 Pa is 8 minutes, then the pressure drop rate coefficient is 0.629 min. -1 If the time taken for the pressure to drop from 100,000 Pa to 650 Pa is 16 minutes, then the pressure drop rate coefficient is 0.315 min. -1 .

[0028] like Figure 1 As shown in the diagram (partial structural diagram not shown), in this embodiment of the invention, the equipment integrating vacuum precooling and vacuum packaging of cooked meat products includes a vacuum precooling machine, a sealing device, and a low-temperature auxiliary device 3.

[0029] The vacuum precooling machine includes a vacuum chamber 11, a vacuum pump, a refrigeration system, sensors, an ultraviolet lamp, a drain valve, and a control system; the sealing equipment includes an air compressor, a cylinder 21, a sealer 22, a power switch 23, and a solenoid valve 24. The refrigeration system, sensors, ultraviolet lamp, cryogenic auxiliary device 3, cylinder 21, and sealer 22 are located inside the vacuum chamber 11, while the vacuum pump, control system, power switch 23, and solenoid valve 24 are located outside the vacuum chamber 11.

[0030] The low-temperature auxiliary device 3 is used to contain cooked meat products and ice-water mixtures. The refrigeration system is used to condense the water vapor generated in the vacuum chamber 11 during the vacuum precooling process. The sensors include temperature sensors and pressure sensors to monitor the temperature and pressure inside the vacuum chamber 11. The vacuum pump is connected to the vacuum chamber 11 and is used to evacuate the vacuum chamber 11. The control system can control the opening and closing of the vacuum pump, refrigeration system, ultraviolet lamp and drain valve.

[0031] The sealing device 22 is used to seal packaging bags. The opening and closing (sealing) action of the sealing device 22 is controlled by the extension and retraction of the cylinder 21. The extension and retraction of the cylinder 21 is controlled by the compressed air from the air compressor. The start of the extension and retraction of the cylinder 21 is controlled by the on / off state of the solenoid valve 24. The compressed air from the air compressor enters the cylinder 21 through the compressed air inlet 4. After the air compressor compresses the air, the solenoid valve 24 controls whether the compressed air is sent into the cylinder 21. The power switch 23 is used to control the opening and closing of the solenoid valve 24.

[0032] Specifically, in this embodiment of the invention, the refrigeration system includes an evaporator.

[0033] An integrated method for vacuum precooling and vacuum packaging of cooked meat products is applicable to the processing of livestock and poultry meat products. In this embodiment of the invention, chicken and pork are used as examples.

[0034] In this embodiment of the invention, the selected chicken is a whole chicken, without cutting, and with its feathers and internal organs removed, and its average carcass weight is 1250±50g; the selected pork tenderloin has an average weight of 1000±100g, a thickness of 6.0±0.2cm, and a length and width of 13.0±0.5cm.

[0035] The present invention will be further illustrated by the following examples.

[0036] Example 1 A method for integrating vacuum precooling and vacuum packaging of cooked meat products (including ice-water mixture-assisted precooling, and direct sealing of the vacuum chamber before repressurization) includes the following steps: S1: Heat the sealing device 22 inside the vacuum chamber 11 to the preset temperature, turn on the ultraviolet lamp inside the vacuum chamber, and close the vacuum chamber door.

[0037] S2: Place the cooked poached chicken in a sterilized aluminum foil bag for pre-packaging, and then steam it in a steamer for 1-2 minutes for sterilization.

[0038] S3: Turn off the ultraviolet lamp in the vacuum chamber 11, put the steamed tin foil packaging bag into the low temperature auxiliary device 3 in the vacuum chamber 11 and fix it, immerse the poached chicken sample in the ice water mixture, and put the tin foil packaging bag mouth into the sealing device 22.

[0039] S4: Close the vacuum chamber door and turn on the ultraviolet lamp; turn on the vacuum pump and adjust the pressure drop rate to 0.36 min. -1 Meanwhile, turn on the evaporator until the temperature of the poached chicken sample drops to 4°C; before repressurization, use the sealer 22 to seal the foil packaging bag to complete the sealing of the foil packaging bag.

[0040] S5: Turn off the vacuum pump, evaporator and ultraviolet lamp, wait for the vacuum chamber to return to normal pressure, and then open the drain valve to remove the condensate.

[0041] S6: Take out the vacuum-packed poached chicken sample, calculate the pre-cooling time and moisture loss rate, and conduct a sensory evaluation of the pre-cooled poached chicken sample.

[0042] Comparative Example 1 A method for integrating vacuum precooling and vacuum packaging of cooked meat products (including the use of an ice-water mixture, followed by re-pressurization, removal from the vacuum chamber, and then vacuum packaging) includes the following steps: S1: Heat the sealing device 22 inside the vacuum chamber 11 to the preset temperature, turn on the ultraviolet lamp inside the vacuum chamber, and close the vacuum chamber door.

[0043] S2: Place the cooked poached chicken in a sterilized aluminum foil bag for pre-packaging, and then steam it in a steamer for 1-2 minutes for sterilization.

[0044] S3: Turn off the ultraviolet lamp in the vacuum chamber 11, put the steamed tin foil packaging bag into the low temperature auxiliary device 3 in the vacuum chamber 11 and fix it, and immerse the poached chicken sample in the ice water mixture.

[0045] S4: Close the vacuum chamber door and turn on the ultraviolet lamp; turn on the vacuum pump and adjust the pressure drop rate to 0.36 min. -1 At the same time, turn on the evaporator until the temperature of the poached chicken sample drops to 4°C.

[0046] S5: Turn off the vacuum pump, evaporator and ultraviolet lamp, wait for the vacuum chamber to return to normal pressure, and then open the drain valve to remove the condensate.

[0047] S6: Take out the poached chicken sample and vacuum pack it again. Calculate the pre-cooling time and moisture loss rate. Perform sensory evaluation on the pre-cooled poached chicken sample.

[0048] Comparative Example 2 A method for integrating vacuum precooling and vacuum packaging of cooked meat products (without ice-water mixture assistance, and direct sealing of the vacuum chamber before repressurization) includes the following steps: S1: Heat the sealing device 22 inside the vacuum chamber 11 to the preset temperature, turn on the ultraviolet lamp inside the vacuum chamber, and close the vacuum chamber door.

[0049] S2: Place the cooked poached chicken in a sterilized aluminum foil bag for pre-packaging, and then steam it in a steamer for 1-2 minutes for sterilization.

[0050] S3: Turn off the ultraviolet lamp inside the vacuum chamber 11, put the steam-cooked tin foil packaging bag into the vacuum chamber and fix it, and put the opening of the tin foil packaging bag into the sealing device.

[0051] S4: Close the vacuum chamber door and turn on the ultraviolet lamp; turn on the vacuum pump and adjust the pressure drop rate to 0.36 min. -1 Meanwhile, turn on the evaporator until the temperature of the poached chicken sample drops to 4°C; before repressurization, use a sealer to seal the foil packaging bag to complete the sealing of the foil packaging bag.

[0052] S5: Turn off the vacuum pump, evaporator and ultraviolet lamp, wait for the vacuum chamber to return to normal pressure, and then open the drain valve to remove the condensate.

[0053] S6: Take out the vacuum-packed poached chicken sample, calculate the pre-cooling time and moisture loss rate, and conduct a sensory evaluation of the pre-cooled poached chicken sample.

[0054] Comparative Example 3 A method for integrating vacuum precooling and vacuum packaging of cooked meat products (without ice-water mixture assistance, after repressurization, the product is removed from the vacuum chamber and then vacuum packaged), comprising the following steps: S1: Heat the sealing device 22 inside the vacuum chamber 11 to the preset temperature, turn on the ultraviolet lamp inside the vacuum chamber, and close the vacuum chamber door.

[0055] S2: Place the cooked poached chicken in a sterilized aluminum foil bag for pre-packaging, and then steam it in a steamer for 1-2 minutes for sterilization.

[0056] S3: Turn off the ultraviolet lamp inside the vacuum chamber 11, put the steam-cooked tin foil packaging bag into the low-temperature auxiliary device 3 inside the vacuum chamber 11 and fix it.

[0057] S4: Close the vacuum chamber door and turn on the ultraviolet lamp; turn on the vacuum pump and adjust the pressure drop rate to 0.36 min. -1 At the same time, turn on the evaporator until the temperature of the poached chicken sample drops to 4°C.

[0058] S5: Turn off the vacuum pump, evaporator and ultraviolet lamp, wait for the vacuum chamber to return to normal pressure, and then open the drain valve to remove the condensate.

[0059] S6: Take out the poached chicken sample and vacuum pack it again. Calculate the pre-cooling time and moisture loss rate. Perform sensory evaluation on the pre-cooled poached chicken sample.

[0060] Table 1. Effects of different precooling methods on precooling time and moisture loss rate of poached chicken.

[0061] The pre-cooling time and moisture loss rate of the poached chicken samples obtained from Examples 1 and Comparative Examples 1-3 were calculated. Table 1 shows that the poached chicken samples obtained from Examples 1 and Comparative Examples 1 achieved both ideal pre-cooling time and moisture loss rate. The pre-cooling time (49.5 min) was only slightly higher than that of Comparative Examples 2-3 (46.5 min); however, the moisture loss rate (4.00%) was significantly lower than that of Comparative Examples 2-3 (11.60%). These results demonstrate that the treatment methods of Examples 1 and Comparative Examples 1 effectively address the technical challenge of achieving both high pre-cooling rate and low moisture loss.

[0062] Table 2. Effects of different precooling methods on the sensory evaluation of poached chicken.

[0063] As can be seen from Table 2, the poached chicken samples obtained by the treatment methods in Comparative Examples 2-3, due to the lack of an ice water-assisted cooling process, had a certain impact on quality. The main effects were as follows: firstly, significant loss of chicken juice occurred, resulting in slight aging of the chicken meat and a deteriorated taste; secondly, the crispness of the chicken skin decreased, leading to a worsened taste. Combining Tables 1-2, it is clear that the treatment method in Example 1 not only achieved a rapid pre-cooling rate and low moisture loss but also maintained the tenderness of the poached chicken meat and the crispness of the skin.

[0064] Comparative Example 4 A method for integrating vacuum precooling and vacuum packaging of cooked meat products includes the following steps: S1: Heat the sealing device 22 inside the vacuum chamber 11 to the preset temperature, turn on the ultraviolet lamp inside the vacuum chamber, and close the vacuum chamber door.

[0065] S2: Place the cooked poached chicken in a sterilized aluminum foil bag for pre-packaging, and then steam it in a steamer for 1-2 minutes for sterilization.

[0066] S3: Turn off the ultraviolet lamp in the vacuum chamber 11, put the steamed tin foil packaging bag into the low temperature auxiliary device 3 in the vacuum chamber 11 and fix it, immerse the poached chicken sample in the ice water mixture, and put the tin foil packaging bag mouth into the sealing device 22.

[0067] S4: Close the vacuum chamber door and turn on the ultraviolet lamp; turn on the vacuum pump and adjust the pressure drop rate to 0.12 min. -1 Meanwhile, turn on the evaporator until the temperature of the poached chicken sample drops to 4°C; before repressurization, use the sealer 22 to seal the foil packaging bag to complete the sealing of the foil packaging bag.

[0068] S5: Turn off the vacuum pump, evaporator and ultraviolet lamp, wait for the vacuum chamber to return to normal pressure, and then open the drain valve to remove the condensate.

[0069] S6: Take out the vacuum-packed poached chicken sample and calculate the pre-cooling time and moisture loss rate.

[0070] Comparative Example 5 A method for integrating vacuum precooling and vacuum packaging of cooked meat products includes the following steps: S1: Heat the sealing device 22 inside the vacuum chamber 11 to the preset temperature, turn on the ultraviolet lamp inside the vacuum chamber, and close the vacuum chamber door.

[0071] S2: Place the cooked poached chicken in a sterilized aluminum foil bag for pre-packaging, and then steam it in a steamer for 1-2 minutes for sterilization.

[0072] S3: Turn off the ultraviolet lamp in the vacuum chamber 11, put the steamed tin foil packaging bag into the low temperature auxiliary device 3 in the vacuum chamber 11 and fix it, immerse the poached chicken sample in the ice water mixture, and put the tin foil packaging bag mouth into the sealing device 22.

[0073] S4: Close the vacuum chamber door and turn on the ultraviolet lamp; turn on the vacuum pump and adjust the pressure drop rate to 0.63 min. -1 Meanwhile, turn on the evaporator until the temperature of the poached chicken sample drops to 4°C; before repressurization, use the sealer 22 to seal the foil packaging bag to complete the sealing of the foil packaging bag.

[0074] S5: Turn off the vacuum pump, evaporator and ultraviolet lamp, wait for the vacuum chamber to return to normal pressure, and then open the drain valve to remove the condensate.

[0075] S6: Take out the vacuum-packed poached chicken sample and calculate the pre-cooling time and moisture loss rate.

[0076] Table 3. Results of different precooling methods on precooling time and moisture loss rate of poached chicken

[0077] Table 3 shows that different pumping speeds affect the final pre-cooling time and moisture loss rate. Relatively speaking, increasing the pre-cooling speed results in a shorter pre-cooling time, but the moisture loss rate also increases accordingly. A comprehensive comparison suggests that, considering both pre-cooling time and moisture loss rate, a moderate pumping speed (0.36 min) is optimal. -1 ) is more appropriate.

[0078] Example 2 To further verify its advantages over other cooked meat products, pork tenderloin was selected as the research object in this embodiment of the invention.

[0079] Example 2 is similar to Example 1 in specific steps, the only difference being that pork tenderloin is used instead of poached chicken.

[0080] Comparative Example 6 Comparative Example 6 is similar to Comparative Example 1 in its specific steps, the only difference being that pork tenderloin is used instead of poached chicken.

[0081] Comparative Example 7 Comparative Example 7 is similar to Comparative Example 2 in its specific steps, the only difference being that pork tenderloin is used instead of poached chicken.

[0082] Comparative Example 8 Comparative Example 8 is similar to Comparative Example 3 in its specific steps, the only difference being that pork tenderloin is used instead of poached chicken.

[0083] Table 4. Results of different precooling methods on precooling time and moisture loss rate of pork tenderloin

[0084] The pre-cooling time and moisture loss rate of the pork tenderloin samples obtained from Examples 2 and Comparative Examples 6-8 were calculated. Table 1 shows that the poached chicken samples obtained from the treatments in Examples 2 and 6 achieved both ideal pre-cooling time and moisture loss rate. The pre-cooling time (52.5 min) was only slightly longer than that of Comparative Examples 7-8 (49.0 min); however, the moisture loss rate (3.88%) was significantly lower than that of Comparative Examples 7-8 (9.25%). The results are similar to those of Examples 1 and Comparative Examples 1-3.

[0085] Table 5. Effects of different pre-cooling methods on total bacterial count and Escherichia coli count in pork tenderloin during refrigeration.

[0086] Table 5 shows that cooked meat treated with different pre-cooling methods all exhibited high microbial safety and met national standards. However, after 45 days of storage, the total bacterial counts of samples treated with methods B and D reached 2900 and 360 CFU / g, respectively, while the total bacterial counts of samples treated with methods in Example 2 and Comparative Example 7 were all less than 10 CFU / g. This indicates that packaging inside a vacuum chamber before re-compression has a significant advantage in microbial safety. After 45 days of refrigeration, the E. coli counts of samples treated with the four methods in Example 2 and Comparative Examples 6-8 were all below 10 CFU / g, demonstrating high microbial safety.

[0087] The improved vacuum precooling technology of this invention innovatively integrates vacuum precooling (with the assistance of a low-temperature device) and vacuum packaging of cooked meat products. It can not only effectively maintain the rapid precooling rate of vacuum precooling and reduce moisture loss, but also effectively improve the microbial safety of the product (without the need for repressurization or external vacuum sealing).

[0088] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and the present invention also intends to include these modifications and variations.

Claims

1. A method for integrating vacuum precooling and vacuum packaging of cooked meat products, characterized in that, Includes the following steps: The cooked meat products are pre-packaged in packaging bags, then sterilized, and then placed in a vacuum chamber. The packaging bags are then placed in an ice-water mixture. The vacuum chamber is closed, the vacuum pump is started to create a vacuum, and once the temperature of the cooked meat products drops to a preset temperature, the packaging bags are sealed, the vacuum pump is turned off, and the pressure is restored to normal to obtain pre-cooled cooked meat products.

2. The method for integrating vacuum precooling and vacuum packaging of cooked meat products according to claim 1, characterized in that, It also includes the following steps: turning on the ultraviolet lamp after closing the vacuum chamber, and turning off the ultraviolet lamp after turning off the vacuum pump.

3. The method for integrating vacuum precooling and vacuum packaging of cooked meat products according to claim 1, characterized in that, It also includes the following steps: after the cooked meat product is placed in the packaging bag, it is sterilized in steam for 1-2 minutes, and the steam temperature is 90~100℃.

4. The method for integrating vacuum precooling and vacuum packaging of cooked meat products according to claim 1, characterized in that, It also includes the following step: the ice-water mixture completely submerges the cooked meat product.

5. The method for integrating vacuum precooling and vacuum packaging of cooked meat products according to claim 1, characterized in that, The temperature of the ice-water mixture is 0~4℃.

6. The method for integrating vacuum precooling and vacuum packaging of cooked meat products according to claim 1, characterized in that, When a vacuum chamber is evacuated, the pressure drop rate coefficient is given by the formula. Sure; in, P This represents the absolute pressure inside the vacuum chamber during operation, expressed in Pa. P i The local atmospheric pressure is expressed in Pa. t is the time for the vacuum pump to evacuate the vacuum chamber, in minutes; Y This is the rate of pressure decrease, in minutes. -1 The pressure drop rate is 0.2-0.6 min. -1 .

7. The method for integrating vacuum precooling and vacuum packaging of cooked meat products according to claim 1, characterized in that, The packaging bags include foil packaging bags.

8. An apparatus for integrating vacuum precooling and vacuum packaging of cooked meat products as described in any one of claims 1 to 7, characterized in that, This includes vacuum precoolers, sealing equipment, and cryogenic auxiliary devices; The vacuum precooling machine includes a vacuum chamber, a vacuum pump, a refrigeration system, sensors, and a control system. The refrigeration system is used to condense the water vapor generated in the vacuum chamber during the vacuum precooling process. The sensors include a temperature sensor and a pressure sensor. The control system is used to control the opening and closing of the vacuum pump and the refrigeration system. The sealing device includes an air compressor, a cylinder, a sealer, and a solenoid valve. The sealer is connected to the cylinder, and the opening and closing of the sealer is controlled by the extension and retraction of the cylinder. The cylinder is also connected to the solenoid valve and communicates with the air compressor. The extension and retraction of the cylinder is controlled by the on / off state of the solenoid valve, and the extension and retraction of the cylinder is accomplished by the compressed air generated by the air compressor. The low-temperature auxiliary device is used to contain the cooked meat product and the ice-water mixture; The refrigeration system, sensors, cylinders, sealers, and cryogenic auxiliary devices are located inside the vacuum chamber, while the control system, air compressor, and solenoid valve are located outside the vacuum chamber. The vacuum pump is located outside the vacuum chamber and is connected to the vacuum chamber.

9. An application of a method for integrating vacuum precooling and vacuum packaging of cooked meat products as described in any one of claims 1 to 7, characterized in that, Suitable for processing livestock and poultry meat products.

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