Improved vacuum precooling system and improved vacuum precooling method for marinated meat products

Abstract

The present invention relates to an improved vacuum precooling system for meat products with sauces and marinades and an improved vacuum precooling method. The improved vacuum precooling system for meat products with sauces and marinades of the present invention comprises: a first vacuum box, a second vacuum box and a vacuum extraction module; the first vacuum box is arranged at a higher height than the second vacuum box; the first vacuum box comprises a vacuum box body, an outer interlayer and a heater; the outer interlayer is sleeved with the inner vacuum box body, and the heater is arranged at the bottom of the inner vacuum box body; the upper end of the inner vacuum box body, the lower end of the inner vacuum box body and the outer interlayer are respectively disconnectably connected to the second vacuum box; the upper end of the inner vacuum box body and the upper end of the second vacuum box are connected to the vacuum extraction module; the outer interlayer is provided with a first water inlet valve, a first water outlet valve and a first drain valve. The improved vacuum precooling system for meat products with sauces and marinades of the present invention has the advantages of fast precooling rate, low water loss and good meat product quality.

Description

Technical Field

[0001] The invention relates to the field of stewing meat products, and in particular to a vacuum precooling system and a vacuum precooling method for stewed meat products. Background Art

[0002] Vacuum precooling mainly reduces the pressure of the material environment to cause the evaporation of free water in the material, and the huge latent heat required for water evaporation comes from the material itself, so that the material can be cooled quickly. It is not difficult to find that the material has a certain pore structure and free water content is the key to ensure that it can be vacuum precooled. On the contrary, this precooling method of cooling by water evaporation will inevitably lead to the loss of water in the material, and the loss of water often reduces the taste and market value of the product (most of the products are calculated by weight).

[0003] At present, the methods for improving the water loss during vacuum precooling of low-temperature cooked meat products are mainly concentrated in the following aspects: the first is water immersion vacuum precooling; that is, the low-temperature cooked meat products are immersed in water or soup and then moved into a vacuum box for vacuum precooling to achieve the effect of improving water loss, but this precooling method will lead to a decrease in the precooling rate compared with the vacuum precooling method; the second is to use a composite precooling method; common composite precooling methods include vacuum precooling first and then air cooling, air cooling first and then vacuum precooling, vacuum precooling first and then water immersion vacuum precooling, water immersion vacuum precooling first and then vacuum precooling combined. Although the above composite precooling methods can achieve a good balance between precooling rate and water loss, sample precooling cannot achieve continuity, thereby increasing the risk of "secondary pollution"; the third is to use water spray vacuum precooling; that is, water spray is used to compensate for water loss after precooling, but this precooling method will greatly increase the risk of "secondary pollution". Although the three vacuum precooling optimization methods mentioned above can compensate for the loss of material moisture, they will lead to a decrease in precooling rate or secondary pollution, increasing costs. Summary of the invention

[0004] Based on this, the object of the present invention is to provide an improved vacuum precooling system and an improved vacuum precooling method for marinated meat products, which have the advantages of fast precooling rate, low water loss and good meat product quality.

[0005] An improved vacuum precooling system for marinated meat products comprises a first vacuum box, a second vacuum box and a vacuum extraction module; the first vacuum box is arranged at a higher height than the second vacuum box; the first vacuum box comprises a vacuum box body, an outer interlayer and a heater; the outer interlayer is sleeved with the inner vacuum box body, and the heater is arranged at the bottom of the inner vacuum box body; the upper end of the inner vacuum box body, the lower end of the inner vacuum box body and the outer interlayer are respectively connected to the second vacuum box in a disconnectable manner; the upper end of the inner vacuum box body and the upper end of the second vacuum box are connected to the vacuum extraction module; the outer interlayer is provided with a first water inlet valve, a first water outlet valve and a first drain valve.

[0006] The improved vacuum precooling system for marinated meat products of the present invention integrates marinating, vacuum precooling and immersion vacuum precooling through the cooperation of a first vacuum box and a second vacuum box, thereby simultaneously ensuring a fast cooling rate, low water loss and high meat product quality.

[0007] Furthermore, it also includes an evaporation and condensation module, which includes a first evaporator and a second evaporator. The upper end of the inner vacuum box and the upper end of the second vacuum box are connected to the vacuum extraction module through the first evaporator and the second evaporator in sequence.

[0008] Furthermore, the first evaporator includes a first evaporator body, a condenser, an expansion valve and a compressor; the refrigeration system of the first evaporator body and the condenser, the expansion valve and the compressor are connected in sequence to form a refrigeration circuit; the second evaporator includes a second evaporator body; the cooling system of the second evaporator body is provided with a second water inlet valve and a second water outlet valve.

[0009] Furthermore, it also includes a connecting valve module, which includes a three-way valve, a first pneumatic valve, a second pneumatic valve, a third pneumatic valve, a fourth pneumatic valve and a fifth pneumatic valve; the upper end of the inner vacuum box is connected to the vacuum extraction module through the first pneumatic valve and the three-way valve in sequence; the upper end of the second vacuum box is connected to the vacuum extraction module through the second pneumatic valve and the three-way valve in sequence; the upper end of the inner vacuum box is connected to the second vacuum box through the third pneumatic valve; the lower end of the inner vacuum box is connected to the second vacuum box through the fourth pneumatic valve; the outer interlayer is connected to the second vacuum box through the fifth pneumatic valve and the third pneumatic valve in sequence, and the outer interlayer is connected to the upper end of the inner vacuum box through the fifth pneumatic valve.

[0010] Furthermore, it also includes a stirring module, which includes an agitator, a stirring speed controller and a stirring motor; the agitator is arranged at the bottom of the inner vacuum box, the rotating shaft of the agitator passes through the inner vacuum box and is connected to the stirring speed controller, and the stirring speed controller is connected to the stirring motor.

[0011] An improved vacuum precooling method, using the above-mentioned improved sauce-marinated meat product vacuum precooling system, specifically comprises the following steps:

[0012] S1: placing the sauce, marinade and meat products into the inner vacuum box, heating the meat products to a first preset temperature and maintaining the temperature until marinating is completed;

[0013] S2: vacuuming the inner vacuum box and the second vacuum box simultaneously to form a water flow in the outer interlayer; and preliminarily cooling the meat product until it reaches a second preset temperature;

[0014] S3: evacuating the outer interlayer and transferring the sauce and broth in the inner vacuum box to the second vacuum box, and then continuing to evacuate the inner vacuum box and performing secondary cooling until the third preset temperature is reached;

[0015] S4 restores the inner vacuum box and the outer interlayer to normal pressure and takes out the meat product.

[0016] Furthermore, the step S2 specifically includes: opening the first water inlet valve and the first water outlet valve to form a water flow in the outer layer; connecting the upper end of the inner vacuum box with the second vacuum box, and simultaneously evacuating the inner vacuum box and the second vacuum box; and preliminarily cooling the meat product until it reaches a second preset temperature.

[0017] Furthermore, the step S2 also includes: stirring the sauce and marinade soup.

[0018] Furthermore, the step S3 specifically includes: closing the first water inlet valve and the first water outlet valve, opening the first drain valve, emptying the water flow in the outer interlayer and then closing the first drain valve; then connecting the outer interlayer and the second vacuum box and the upper end of the inner vacuum box; at the same time, opening the fourth pneumatic valve, connecting the lower end of the inner vacuum box and the second vacuum box, and flowing the sauce and brine in the inner vacuum box into the second vacuum box under a vacuum state; after transferring the sauce and brine to the second vacuum box, disconnecting the second vacuum box, and continuing to vacuum the inner vacuum box for secondary cooling until the meat product reaches a third preset temperature.

[0019] Furthermore, the method further comprises step S5: connecting the lower end of the inner vacuum box with the second vacuum box, evacuating the inner vacuum box, generating negative pressure to cause the sauce and broth in the second vacuum box to flow back into the inner vacuum box.

[0020] For better understanding and implementation, the present invention is described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1This is a schematic diagram of a vacuum precooling system for improved marinated meat products according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In the prior art, the vacuum precooling operation method is mainly to directly put the low-temperature cooked meat products into the vacuum precooling system, and to evaporate and cool the low-temperature cooked meat products by vacuuming; although the above precooling method has a fast cooling speed, it causes a considerable loss of water; according to the calculation that every 1% of water loss decreases by 5-6°C, a temperature difference of nearly 68°C (72-4°C) will cause a water loss of about 10%, and most of the water vapor will be condensed by the condenser 2011 and finally discharged, which has a great impact on the finished product. Therefore, the application of vacuum precooling technology in the precooling of low-temperature cooked meat products is greatly limited. The method of replenishing water from the outside often leads to problems such as poor quality of low-temperature cooked meat products and "secondary pollution".

[0023] In order to solve the above problems, the inventors proposed an improved vacuum pre-cooling system and an improved vacuum pre-cooling method for marinated meat products. By integrating marinating and immersion vacuum pre-cooling equipment (including cooling of the marinade soup) and vacuum pre-cooling equipment (without the marinade soup), an uninterrupted connection between immersion vacuum pre-cooling and vacuum pre-cooling is achieved, thus solving the difficult problem of "not being able to have both" of the three advantages of vacuum pre-cooling, namely, fast pre-cooling rate, low water loss and little quality change.

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be noted that the terms "vertical direction", "up", "down", "horizontal", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, "first", "second", "third", and "fourth" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0026] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a heat-conducting connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, or a connection through an intermediate medium, or the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] Example 1

[0028] The embodiment of the present application provides an improved vacuum precooling system for marinated meat products, comprising a first vacuum box, a second vacuum box 2, a vacuum extraction module 3 and an evaporation condensation module. The first vacuum box is set at a higher height than the second vacuum box 2 and is connected to the second vacuum box 2. The first vacuum box and the second vacuum box 2 are connected to the vacuum extraction module 3 after passing through the evaporation condensation module. The first vacuum box is used for marinating and vacuum precooling meat products, the second vacuum box 2 is used to assist in marinating and vacuum precooling operations, the vacuum extraction module 3 is used to evacuate the first vacuum box and the second vacuum box 2, and the evaporation condensation module is used to capture the water vapor generated during the vacuum process.

[0029] The first vacuum box includes an inner vacuum box 101, an outer interlayer 102, a stirring module 103, a heater 104 and a temperature control module 105. The outer interlayer 102 is sleeved with the inner vacuum box 101, the stirring module 103 and the heater 104 are arranged at the bottom of the inner vacuum box 101, and the temperature control module 105 is used to detect the temperature and pressure in the inner vacuum box 101 and feedback the control signal. The upper end of the inner vacuum box 101, the lower end of the inner vacuum box 101 and the outer interlayer 102 are respectively connected to the second vacuum box 2 in a disconnectable manner; the upper end of the inner vacuum box 101 and the upper end of the second vacuum box 2 are connected to the vacuum extraction module 3 after passing through the evaporation condensation module.

[0030] In some embodiments, the improved vacuum pre-cooling system for marinated meat products of the present invention also includes a connecting valve module, which includes a three-way valve, a first pneumatic valve 501, a second pneumatic valve 502, a third pneumatic valve 503, a fourth pneumatic valve 504 and a fifth pneumatic valve 505.

[0031] The upper end of the inner vacuum box 101 is connected to the vacuum extraction module 3 through the first pneumatic valve 501 and the three-way valve in sequence; the upper end of the second vacuum box 2 is connected to the vacuum extraction module 3 through the second pneumatic valve 502 and the three-way valve in sequence. The upper end of the inner vacuum box 101 is connected to the second vacuum box 2 through the third pneumatic valve 503; the lower end of the inner vacuum box 101 is connected to the second vacuum box 2 through the fourth pneumatic valve 504; the outer interlayer 102 is provided with a first water inlet valve 1021, a first water outlet valve 1022 and a first drain valve 102a, the outer interlayer 102 is connected to the second vacuum box 2 through the fifth pneumatic valve 505 and the third pneumatic valve 503 in sequence, and the outer interlayer 102 is connected to the upper end of the inner vacuum box 101 through the fifth pneumatic valve 505.

[0032] During operation, the meat product is placed on the lower side of the inner vacuum box 101. In some embodiments, the first vacuum box further comprises a fixing device 101a for fixing the meat product, and the fixing device 101a is arranged on the lower side of the inner vacuum box 101. Further, the fixing device 101a is a stainless steel mesh.

[0033] In some embodiments, the stirring module 103 includes a stirrer 1031, a stirring speed controller 1032, and a stirring motor 1033. The stirrer 1031 is disposed at the bottom of the inner vacuum box 101, and the rotating shaft of the stirrer 1031 passes through the inner vacuum box 101 and is connected to the stirring speed controller 1032, and the stirring speed controller 1032 is connected to the stirring motor 1033. The stirring module 103 can accelerate the cooling of the meat product during the immersion vacuum precooling process.

[0034] In some embodiments, the temperature control module 105 includes a temperature sensor, a pressure sensor and a data processor. The probes of the temperature sensor and the pressure sensor are arranged in the inner vacuum box 101, and the temperature sensor and the pressure sensor are electrically connected to the data processor. Further, the temperature control module 105 also includes an exhaust valve, which is arranged on the inner vacuum box 101.

[0035] In some embodiments, the vacuum extraction module 3 includes an extraction motor 301, a vacuum pump 302 and a solenoid valve 303. The extraction motor 301 is connected to the vacuum pump 302, and the vacuum pump 302 is connected to the first vacuum box and the second vacuum box 2 through the solenoid valve 303.

[0036] In some embodiments, the evaporation condensation module includes a first evaporator and a second evaporator, and the vacuum extraction module 3 is connected to the first vacuum box and the second vacuum box 2 through the first evaporator and the second evaporator in sequence. The first evaporator includes a first evaporator body 201, a condenser 2011, an expansion valve 2012 and a compressor 2013; the first evaporator body 201 is provided with a second drain valve 201a; the refrigeration system of the first evaporator body 201 and the condenser 2011, the expansion valve 2012, and the compressor 2013 are connected in sequence to form a refrigeration circuit, and the first evaporator is cooled by the refrigeration circuit to condense and collect the water vapor therein. The second evaporator includes a second evaporator body 202; the second evaporator body 202 is provided with a third drain valve 202a; the cooling system of the second evaporator body 202 is provided with a second water inlet valve 2021 and a second water outlet valve 2022, and the second evaporator is cooled by water flow to condense and collect the water vapor therein. Through the two evaporators, the condensation efficiency of the evaporation condensation module is improved, and water vapor is prevented from entering the vacuum extraction module 3.

[0037] When the improved vacuum precooling system for marinated meat products is used for marinating, the meat products are placed on the lower side of the inner vacuum box 101, and the prepared marinade is added to just cover the meat products. The inner vacuum box 101 is heated to a predetermined temperature by the heater 104, and the meat products are marinated. At this time, all valves in the system are closed, and the outer interlayer 102 is an air layer, which has a heat preservation effect.

[0038] After the marinating is completed, the improved vacuum precooling system for marinated meat products is initially cooled. During the initial cooling, the stirring module 103 is first turned on to stir the marinated soup at a preset frequency to assist in cooling; then the first water inlet valve 1021 and the second water outlet valve 2022 are opened to generate water flow in the outer interlayer 102, thereby cooling the inner vacuum box 101; then the evaporation condensation module, the first pneumatic valve 501, the second pneumatic valve 502 and the vacuum extraction module 3 are turned on to connect the inner vacuum box 101, the second vacuum box 2 and the vacuum extraction module 3, and at the same time, the inner vacuum box 101 and the second vacuum box 2 are depressurized until the temperature of the meat product drops to a preset temperature. In some embodiments, the preset temperature for initial cooling is 20°C.

[0039] After the initial cooling is completed, the improved vacuum precooling system for marinated meat products is vacuum precooled. During vacuum precooling, first close the first water inlet valve 1021 and the first water outlet valve 1022, open the drain valve, and drain the water in the outer interlayer 102; then open the fourth pneumatic valve 504 and the fifth pneumatic valve 505 to form a vacuum in the outer interlayer 102, and allow the marinated soup in the inner vacuum box 101 to flow into the second vacuum box 2; after the marinated soup has finished flowing in, close the second pneumatic valve 502, the third pneumatic valve 503 and the fourth pneumatic valve 504; continue to reduce the pressure in the inner vacuum box 101, and after it drops to a preset pressure, maintain the pressure to continue to cool down the inner vacuum box 101 until the preset temperature. In some embodiments, the preset pressure of vacuum precooling is 650Pa, and the preset temperature is 4°C.

[0040] After the precooling is completed, the vacuum extraction module 3 and the evaporation condensation module are turned off, the first vacuum box and the second vacuum box 2 are restored to normal pressure, the condensed water collected by the evaporation condensation module is discharged, and the meat product is taken out.

[0041] The present application also provides an improved vacuum precooling method using the improved vacuum precooling system for marinated meat products, which specifically includes the following steps:

[0042] S1: Put the sauce, marinade and meat products into the inner vacuum box 101, turn on the heater 104, heat the meat products to a first preset temperature and maintain the temperature until the marinating is completed.

[0043] After S2 marinating is completed, turn on the stirring module 103 to stir the marinade; turn on the vacuum extraction module 3, the first pneumatic valve 501, the second pneumatic valve 502 and the third pneumatic valve 503 of the evaporation condensation module; connect the upper end of the inner vacuum box 101 with the second vacuum box 2, and evacuate the inner vacuum box 101 and the second vacuum box 2 at the same time; open the first water inlet valve 1021 and the first water outlet valve 1022 to form a water flow in the outer interlayer 102; thereby preliminarily cooling the meat product until it reaches the second preset temperature.

[0044] After the initial cooling of S3 is completed, the first water inlet valve 1021 and the first water outlet valve 1022 are closed, and the first drain valve 102a is opened to drain the water in the outer interlayer 102 and then close the first drain valve 102a; then the fifth pneumatic valve 505 is opened to connect the outer interlayer 102 and the second vacuum box 2; at the same time, the fourth pneumatic valve 504 is opened to connect the lower end of the inner vacuum box 101 and the second vacuum box 2, and the sauce and brine in the inner vacuum box 101 flows into the second vacuum box 2 under a vacuum state; after the sauce and brine is transferred to the second vacuum box 2, the second pneumatic valve 502, the third pneumatic valve 503 and the fourth pneumatic valve 504 are closed at the same time, and the inner vacuum box 101 is continued to be vacuumed for secondary cooling until the meat product reaches the third preset temperature.

[0045] After the secondary cooling in S4 is completed, the vacuum extraction module 3 and the evaporation condensation module are closed to restore the inner vacuum box 101 and the outer interlayer 102 to normal pressure; the second drain valve 201a and the third drain valve 202a are opened to discharge the condensed water collected by the evaporation condensation module; the meat products are taken out and vacuum packed in the clean room.

[0046] In some embodiments, after the improved vacuum pre-cooling is completed, the sauce and broth in the second vacuum box 2 can be returned to the inner vacuum box 101 through the pressure difference to achieve recycling.

[0047] The improved vacuum precooling system and improved vacuum precooling method for meat products of sauce and marinade of the embodiment of the present invention complete the marinating, immersion vacuum precooling (including the sauce and marinade soup for cooling) and vacuum precooling (without the sauce and marinade soup) of meat products in a single device, seamlessly connect the immersion vacuum precooling and vacuum precooling, reduce the time of sample transfer during operation and the "secondary pollution" that may be caused during the transfer process, and correspondingly reduce the operation procedures and reduce the operating cost (avoiding secondary vacuum pumping); and the marinating and precooling are completed in a single device, and do not contact the external environment in the middle, which can be clean and hygienic, easy to operate, and conducive to promotion and industrial development. The outer interlayer 102 is added to play a role of heat preservation in the marinating process, an auxiliary cooling role in the immersion vacuum precooling process, and a heat preservation role in the vacuum precooling process. The problem of slow cooling rate of samples in the post-immersion vacuum precooling stage is solved. At the same time, after the immersion vacuum precooling is completed, some sauce and marinade soup will still adhere to the surface of the sample, thereby further reducing the water loss caused by vacuum precooling. It solves the difficult problem of "not having both" fast pre-cooling rate, low water loss and little quality change.

[0048] Example 2

[0049] In order to reflect the advantages of the present invention, the improved vacuum precooling method of the present invention was compared with air cooling, vacuum precooling and immersion vacuum precooling, and chicken carcasses were used as samples for the experiment.

[0050] (1) The specific steps of the improved vacuum precooling method are as follows:

[0051] SA1 cleans the first vacuum box and the second vacuum box 2, then puts a certain amount of tap water in, and uses the heater 104 to disinfect the first vacuum box and the second vacuum box 2. Then, put the complete and cleaned chicken carcass (without viscera, net content 1.5kg) into the stainless steel net in the first vacuum box and fix it. Then, pour in the prepared sauce and marinade, just enough to cover the sample. Then, marinate the sample at 90°C until the marinating is completed.

[0052] SA2 performs preliminary cooling, which specifically includes the following steps:

[0053] SA21 turns on the stirring module 103 to stir the sauce and brine, and the stirring frequency is set to 20 Hz;

[0054] SA22 opens the first water inlet valve 1021 and the first water outlet valve 1022 to cool the inner vacuum box 101 through the outer interlayer 102. The first water inlet valve 1021 is connected to the tap water pipe, and the tap water temperature changes with the season (the tap water temperature is about 22°C during the test);

[0055] SA23 turns on the evaporation condensation module; wherein the refrigerant temperature in the first evaporator is set to -10 to -5°C; the second water inlet valve 2021 of the second evaporator is connected to the tap water pipe (the tap water temperature during the test is about 22°C);

[0056] SA24 opens the vacuum extraction module 3, the first pneumatic valve 501, the second pneumatic valve 502 and the third pneumatic valve 503, and the vacuum pump 302 is set to a pumping rate of 0.5 min -1 ; The inner vacuum box 101 and the second vacuum box 2 are depressurized simultaneously until the sample temperature drops to 20°C;

[0057] SA3 performs secondary cooling, specifically including the following steps:

[0058] SA31 closes the first water inlet valve 1021 and the first water outlet valve 1022, opens the first drain valve 102a, drains the water in the outer interlayer 102, and then closes the first drain valve 102a;

[0059] SA32 opens the fourth pneumatic valve 504 and the fifth pneumatic valve 505, evacuates the outer interlayer 102 and allows the sauce and broth to flow into the second vacuum box 2; after the sauce and broth have finished flowing in, closes the second pneumatic valve 502, the third pneumatic valve 503 and the fourth pneumatic valve 504;

[0060] SA33 continues to reduce the pressure of the inner vacuum box 101 until the sample temperature drops to 4°C.

[0061] After the secondary cooling of SA4 is completed, the vacuum extraction module 3 and the evaporation condensation module are closed to restore the inner vacuum box 101 and the outer interlayer 102 to normal pressure; the second drain valve 201a and the third drain valve 202a are opened to discharge the condensed water collected by the evaporation condensation module.

[0062] SA5 takes out the sample, weighs the sample, calculates the water loss rate, and vacuum packs it in a clean room. Refrigerate the sample at 4°C and test the total number of colonies on the 1st, 3rd, 5th, 7th, and 9th day.

[0063] (2) The specific steps of air cooling method are as follows:

[0064] The steps of SB1 are the same as those of SA1.

[0065] SB2 was placed in a cold storage with the temperature set at 4°C, wind speed at 1±0.5m / s, and relative humidity at 90% until the center temperature of the sample dropped to 4°C.

[0066] SB3 and SA5 have the same steps.

[0067] (3) The specific steps of vacuum precooling method are as follows:

[0068] The steps of SC1 and SA1 are the same.

[0069] SC2 opens the fourth pneumatic valve 504 to allow the sauce and broth to flow into the second vacuum box 2; after the sauce and broth have finished flowing in, close the second pneumatic valve 502, the third pneumatic valve 503 and the fourth pneumatic valve 504, and open the fifth pneumatic valve 505.

[0070] SC3 turns on the evaporation condensation module and the vacuum extraction module 3, and controls the vacuum pump 302 to have a pumping rate of 0.5 min -1 The inner vacuum box 101 is lowered to 650 Pa and maintained until the center temperature of the sample drops to 4°C.

[0071] SC4 is the same as SA4 and SA5 steps.

[0072] (4) The specific steps of impregnation vacuum precooling are as follows:

[0073] The steps of SD1 and SA1 are the same.

[0074] SD2 is the same as SA2, and then the temperature is continued to decrease until the center temperature of the sample reaches 4°C.

[0075] SD3 has the same steps as SA4 and SA5.

[0076] After the experiment is completed, the experimental data are obtained and the results are shown in Table 1 and Table 2.

[0077] Table 1 Precooling time and sample water loss rate of each precooling method in this embodiment

[0078]

[0079]

[0080] As can be seen from Table 1, the improved vacuum precooling method of the present invention obtains a relatively ideal precooling time and water loss rate. Its precooling time (52.5min) is only slightly higher than vacuum precooling (45.5min), and much lower than immersion vacuum precooling (78.5min) and air cooling (240.5min); similarly, its water loss rate (3.85%) is slightly higher than immersion vacuum precooling (3.13%), and much lower than air cooling (5.21%) and vacuum precooling (12.19%). As can be seen from the above results, the improved vacuum precooling method of the present invention can break the problem that both fast precooling rate and low water loss cannot be achieved at the same time.

[0081] Table 2 Changes in the total number of bacterial counts in chicken carcasses treated with various precooling methods during refrigeration in this example

[0082]

[0083] It can be seen from Table 2 that the samples treated with vacuum precooling, immersion vacuum precooling and improved vacuum precooling have higher microbial safety. After 9 days of storage, the samples cooled by air reached 1200 CFU / g, while the total colony counts of the samples treated with vacuum precooling, immersion vacuum precooling and improved vacuum precooling were all less than 10 CFU / g.

[0084] Example 3

[0085] Furthermore, beef shank (average weight of 3 kg) was used as a sample, and the other steps were the same as in Example 2. The improved vacuum precooling method of the present invention was compared with air cooling, vacuum precooling and immersion vacuum precooling. The results are shown in Tables 3 and 4.

[0086] Table 3 Precooling time and sample water loss rate of each precooling method in this embodiment As can be seen from Table 3, the precooling effect of the improved vacuum precooling in the braised beef is similar to that on the chicken carcass, and both have achieved relatively ideal precooling time and moisture loss rate. Its precooling time (125.5min) is only slightly higher than vacuum precooling (108.5min), and much lower than immersion vacuum precooling (195.5min) and air cooling (515.5min); similarly, its moisture loss rate (3.92%) is slightly higher than immersion vacuum precooling (3.45%), and much lower than air cooling (5.08%) and vacuum precooling (12.39%). From the above results, it can be seen that the improved vacuum precooling method can break the problem of fast precooling rate and low moisture loss.

[0087] Table 4 Changes in the total number of bacterial counts of the braised beef treated with each precooling method during refrigeration in this embodiment

[0088]

[0089] The changes in the total colony count of the braised beef in different precooling methods during refrigeration in Table 4 are similar to those in Table 2. This shows that the braised beef in vacuum precooling, immersion vacuum precooling and improved vacuum precooling methods all have higher microbial safety.

[0090] The improved vacuum precooling system and improved vacuum precooling method for marinated meat products of the present invention complete the marinating and precooling steps of marinated meat products in a single device. At the same time, the immersion vacuum precooling and vacuum precooling modes are continuously and uninterruptedly connected, thereby greatly reducing the precooling time and energy consumption, and effectively improving the microbial safety of the product (no need to transfer samples and re-pressurize-depressurize processes in the middle).

[0091] The above results show that the improved vacuum precooling method of the present invention can not only obtain extremely fast precooling rate and low water loss, but also obtain relatively ideal microbial safety, thereby greatly promoting the application of vacuum precooling technology in precooling of marinated meat products. At the same time, the device is easy to operate and can realize the simultaneous precooling of large quantities of marinated meat products.

[0092] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and the present invention is also intended to include these modifications and modifications.

Claims

1. An improved vacuum precooling system for marinated meat products, characterized in that: The invention comprises a first vacuum box, a second vacuum box and a vacuum extraction module; the first vacuum box is arranged at a higher height than the second vacuum box; the first vacuum box comprises an inner vacuum box body, an outer interlayer and a heater; the outer interlayer is sleeved with the inner vacuum box body, and the heater is arranged at the bottom of the inner vacuum box body; the upper end of the inner vacuum box body, the lower end of the inner vacuum box body and the outer interlayer are respectively connected to the second vacuum box in a disconnectable manner; the upper end of the inner vacuum box body and the upper end of the second vacuum box are both connected to the vacuum extraction module; the outer interlayer is provided with a first water inlet valve, a first water outlet valve and a first drain valve; and the invention also comprises an evaporation condensation module, the evaporation condensation module The evaporation condensation module comprises a first evaporator and a second evaporator, and the upper end of the inner vacuum box and the upper end of the second vacuum box are connected to the vacuum extraction module after passing through the first evaporator and the second evaporator in sequence; it also comprises a connecting valve module, and the connecting valve module comprises a fourth pneumatic valve; the lower end of the inner vacuum box is connected to the second vacuum box through the fourth pneumatic valve; the vacuum extraction module is used to evacuate the first vacuum box and the second vacuum box, and the evaporation condensation module is used to capture the water vapor generated during the vacuum process; the method for using the improved vacuum precooling system for marinated meat products comprises the following steps: S1: placing the sauce, marinade and meat products into the inner vacuum box, heating the meat products to a first preset temperature and maintaining the temperature until marinating is completed; S2: vacuuming the inner vacuum box and the second vacuum box simultaneously to form a water flow in the outer interlayer; and preliminarily cooling the meat product until it reaches a second preset temperature; S3: evacuating the outer interlayer and transferring the sauce and broth in the inner vacuum box to the second vacuum box, and then continuing to evacuate the inner vacuum box and performing secondary cooling until the third preset temperature is reached; S4: restoring the inner vacuum box and the outer interlayer to normal pressure, and taking out the meat product; The step S2 specifically includes opening the first water inlet valve and the first water outlet valve to form a water flow in the outer interlayer; connecting the upper end of the inner vacuum box with the second vacuum box, and evacuating the inner vacuum box and the second vacuum box at the same time; and preliminarily cooling the meat product until it reaches a second preset temperature; The S3 specifically includes closing the first water inlet valve and the first water outlet valve, opening the first drain valve, emptying the water flow in the outer interlayer and then closing the first drain valve; then connecting the outer interlayer and the second vacuum box and the upper end of the inner vacuum box; at the same time, opening the fourth pneumatic valve, connecting the lower end of the inner vacuum box and the second vacuum box, and flowing the sauce and sauce in the inner vacuum box into the second vacuum box under a vacuum state; after transferring the sauce and sauce to the second vacuum box, disconnecting the second vacuum box, and continuing to evacuate the inner vacuum box for secondary cooling until the meat product reaches a third preset temperature.

2. The improved vacuum precooling system for marinated meat products according to claim 1, characterized in that: The first evaporator includes a first evaporator body, a condenser, an expansion valve and a compressor; the refrigeration system of the first evaporator body and the condenser, the expansion valve and the compressor are connected in sequence to form a refrigeration circuit; the second evaporator includes a second evaporator body; the cooling system of the second evaporator body is provided with a second water inlet valve and a second water outlet valve.

3. The improved vacuum precooling system for marinated meat products according to claim 1, characterized in that: The connecting valve module includes a three-way valve, a first pneumatic valve, a second pneumatic valve, a third pneumatic valve and a fifth pneumatic valve; the upper end of the inner vacuum box passes through the first pneumatic valve and the three-way valve in sequence and is connected to the vacuum extraction module; the upper end of the second vacuum box passes through the second pneumatic valve and the three-way valve in sequence and is connected to the vacuum extraction module; the upper end of the inner vacuum box is connected to the second vacuum box through the third pneumatic valve; the outer interlayer passes through the fifth pneumatic valve and the third pneumatic valve in sequence and is connected to the second vacuum box, and the outer interlayer is connected to the upper end of the inner vacuum box through the fifth pneumatic valve.

4. The improved vacuum precooling system for marinated meat products according to claim 1, characterized in that: It also includes a stirring module, which includes an agitator, a stirring speed controller and a stirring motor; the agitator is arranged at the bottom of the inner vacuum box, the rotating shaft of the agitator passes through the inner vacuum box and is connected to the stirring speed controller, and the stirring speed controller is connected to the stirring motor.

5. An improved vacuum precooling method, characterized in that: The improved vacuum precooling system for marinated meat products according to any one of claims 1 to 4 specifically comprises the following steps: S1: placing the sauce, marinade and meat products into the inner vacuum box, heating the meat products to a first preset temperature and maintaining the temperature until marinating is completed; S2: vacuuming the inner vacuum box and the second vacuum box simultaneously to form a water flow in the outer interlayer; and preliminarily cooling the meat product until it reaches a second preset temperature; S3: evacuating the outer interlayer and transferring the sauce and broth in the inner vacuum box to the second vacuum box, and then continuing to evacuate the inner vacuum box and performing secondary cooling until the third preset temperature is reached; S4: returning the inner vacuum box and the outer interlayer to normal pressure, and taking out the meat product.

6. The improved vacuum precooling method according to claim 5, characterized in that: The step S2 specifically includes: opening the first water inlet valve and the first water outlet valve to form a water flow in the outer interlayer; connecting the upper end of the inner vacuum box with the second vacuum box, and evacuating the inner vacuum box and the second vacuum box at the same time; and preliminarily cooling the meat product until it reaches a second preset temperature.

7. The improved vacuum precooling method according to claim 5, characterized in that: The step S2 also includes: stirring the sauce and marinade.

8. The improved vacuum precooling method according to claim 5, characterized in that: The step S3 specifically includes: closing the first water inlet valve and the first water outlet valve, opening the first drain valve, emptying the water flow in the outer interlayer and then closing the first drain valve; then connecting the outer interlayer and the second vacuum box and the upper end of the inner vacuum box; at the same time, opening the fourth pneumatic valve, connecting the lower end of the inner vacuum box and the second vacuum box, and flowing the sauce and sauce in the inner vacuum box into the second vacuum box under a vacuum state; after transferring the sauce and sauce to the second vacuum box, disconnecting the second vacuum box, and continuing to evacuate the inner vacuum box for secondary cooling until the meat product reaches a third preset temperature.

9. The improved vacuum precooling method according to any one of claims 5 to 8, characterized in that: The method further comprises step S5: connecting the lower end of the inner vacuum box with the second vacuum box, evacuating the inner vacuum box, and allowing the sauce and broth in the second vacuum box to flow back into the inner vacuum box.

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