A method for preserving meat products in industrial cold stores with a solid state weak magnetic field

Abstract

The application discloses a method for preserving meat products in an industrial cold storage by using a weak magnetic field, and belongs to the technical field of meat product preservation. The method provides a specific intermittent oscillating weak magnetic field to the environment of the meat products during low-temperature preservation. Specifically, the meat products are preserved in a cold storage at a low-temperature environment temperature of-40 to 15 DEG C, and a weak magnetic field is provided to the environment of the meat products during the preservation. The weak magnetic field is an intermittent oscillating weak magnetic field, the ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:2-1:5, the oscillating frequency of the oscillating weak magnetic field is 0-1 Hz, and the magnetic field strength of the weak magnetic field is 0.1-5.0 mT. The method is simple, suitable for industrial cold storage, and can effectively reduce the juice loss of the meat products and save costs.

Description

Technical Field

[0001] This invention relates to a method for preserving meat products in an industrial cold storage facility with a fixed weak magnetic field, belonging to the field of meat product preservation technology. Background Technology

[0002] Meat products are prone to quality deterioration during long-term storage, such as worsening color and odor, increased acid value, protein dissolution, and microbial growth, seriously affecting consumer quality and food safety. Freezing at -18℃ can achieve low-temperature sterilization and extend shelf life. However, during freezing, water migrates from the sample tissue, forming large, uneven ice crystals, which cause mechanical damage to tissue cells, leading to tissue deterioration. During thawing, due to the damage to cell membranes and tissue structures, tissue cells cannot reabsorb the water that has migrated outside the cells, resulting in juice loss, and excessive oxidation of fats and proteins further reduces food quality.

[0003] Common cold storage preservation methods primarily rely on temperature control to slow down the growth of microorganisms in meat products. However, when large quantities of meat products are stacked, some are compressed, causing tissue damage. Furthermore, ice crystals damage cells during freezing, altering cellular metabolism and leading to juice loss, microbial and mold growth, and a decline in meat quality after thawing. Water molecules lack a fixed magnetic dipole moment, exhibiting diamagnetism. Magnetic fields, with their orientation, induce spin polarization and ordering in water molecules, effectively reducing large ice crystal formation and cell damage. Magnetic fields can also influence bacterial metabolism and inhibit growth, making them highly promising for freezing and refrigeration. However, existing magnetic field treatment methods typically require high magnetic field strength and are unsuitable for large industrial cold storage installations. For example, a reported method for extending the shelf life of beef uses electromagnetic field preservation equipment with the following parameters: 220V power supply and power <0.5W / m². 3 Output current ≤10mA, output voltage ≤3000V, electromagnetic field BX3000, electromagnetic field voltage value 2000~3000, space voltage value 50~200, applicable space 25~30m 3 This method uses a specific electromagnetic field preservation device, which emits low-frequency electrostatic waves of 50-60Hz through a discharge plate to achieve preservation. However, the preservation effect needs to be improved, for example, there is a significant loss of juice. Summary of the Invention

[0004] To address at least one of the aforementioned problems, this invention provides a method for preserving meat products in an industrial cold storage facility with a fixed weak magnetic field. By providing a specific intermittent oscillating weak magnetic field to the environment where the meat products are stored at low temperatures, the loss of juices from the meat products is effectively reduced, thus saving costs.

[0005] In the early stages of research, the inventors' team conducted in-depth studies on the effects of magnetic field environment on meat product preservation. They discovered that controlling the magnetic field environment can have different and unexpected effects on the preservation effect, and only by effectively controlling the magnetic field environment can the preservation effect be effectively achieved.

[0006] The present invention relates to a method for preserving meat products in an industrial cold storage based on a weak magnetic field. The method involves preserving the meat products in a cold storage environment at a low temperature of -40 to 15°C, and providing a weak magnetic field to the environment in which the meat products are stored during the preservation period. The weak magnetic field is an intermittent oscillating weak magnetic field, with the ratio of the intermittent time of the magnetic field within each intermittent cycle being 1:2 to 1:5, i.e., the ratio of the working time to the closing time of the oscillating weak magnetic field within each intermittent cycle is 1:(2 to 5). The oscillation frequency of the oscillating weak magnetic field is 0 to 1 Hz, and the magnetic field strength is 0.1 to 5.0 mT.

[0007] In one embodiment, the method further controls the ambient relative humidity to be 70–99%.

[0008] In one embodiment, the oscillation frequency of the oscillating weak magnetic field is 0.1 to 1 Hz.

[0009] In one embodiment, the oscillation frequency of the oscillating weak magnetic field is 0.5 Hz.

[0010] In one embodiment, the intermittent oscillating weak magnetic field is controlled by a weak magnetic field generating unit, which further includes an oscillating weak magnetic field power supply and a circuit control module. The oscillating magnetic field strength, frequency, and intermittent time ratio of the weak magnetic field are adjusted by the circuit control system to adjust at least one of these factors to ensure the environment meets the weak magnetic field requirements. The intermittent oscillating weak magnetic field can be achieved using existing technologies, such as the device described in patent CN113192719A, by amplifying the wires, the weak magnetic field power supply, and the circuit control module.

[0011] In one embodiment, after the meat products are pre-cooled to a uniform storage temperature, they are stacked in a cold storage facility or laid flat for small samples.

[0012] In one embodiment, the meat product storage capacity is 100 kg to 300 tons.

[0013] In one embodiment, the meat products include, but are not limited to, livestock meat such as pork and beef; poultry such as chicken and duck; and aquatic products such as salmon and abalone.

[0014] The present invention also provides a method for reducing juice loss during pork storage, the method comprising:

[0015] S1. Raw material pretreatment: Place the pork in a pre-cooling warehouse to cool it down to 4°C, wrap the pork in plastic film and pack it into boxes, and then store it in stacks in an industrial cold storage.

[0016] S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 5.0mT and an oscillation frequency of 0.5Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:5. The low temperature environment is -20℃ and the relative humidity is 97%.

[0017] In one embodiment, the method further controls the ambient relative humidity to be 80–99%.

[0018] The present invention also provides a method for reducing juice loss during the storage of chicken breast, the method comprising:

[0019] S1. Raw material pretreatment: Place the chicken breast in a pre-cooling warehouse to cool it down to 4°C, wrap the chicken breast in plastic film and pack it into boxes, and store it in stacks in an industrial cold storage.

[0020] S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 3mT and an oscillation frequency of 0.5Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:3. The low temperature environment is -18℃ and the relative humidity is 98%.

[0021] In one embodiment, the method further controls the ambient relative humidity to be 80–99%.

[0022] Advantages and effects of the present invention:

[0023] (1) The method of the present invention is simple. It only requires applying an intermittent oscillating weak magnetic field with a magnetic field strength of 0.1 to 5.0 mT to the environment where the meat products are located on the basis of a conventional industrial cold storage. It is suitable for the assembly of large industrial cold storage.

[0024] (2) The method of the present invention has good preservation effect and high cost saving. After 15 days of storage of pork, the juice loss rate can be controlled at 0.82% under optimal conditions, and at least 480 to 3740 yuan can be saved for every 10 tons of storage. The results of 30 days of storage of chicken breast show that the juice loss rate can be controlled at 1.22% under optimal conditions, and at least 350 to 2500 yuan can be saved for every 10 tons of storage. Detailed Implementation

[0025] In view of the many shortcomings of the prior art, the inventors of this case, through long-term research and extensive practice, have proposed the technical solution of this invention. However, it should be understood that within the scope of this invention, the above-mentioned technical features of this invention and the technical features specifically described below (exemplary embodiments) can be combined with each other to form new or preferred technical solutions. Due to space limitations, they will not be described in detail here.

[0026] In the following embodiments, unless otherwise specified, all raw materials, reagents, reaction equipment, testing equipment and methods used can be obtained through market purchases or other means.

[0027] Example 1: A method for preserving pork in a cold storage

[0028] A method for preserving pork in a cold storage facility includes the following steps:

[0029] S1. Raw material pretreatment: 10 tons of pork were placed in a pre-cooling warehouse to cool down to 4℃. The pork was then wrapped in plastic film, boxed, and stacked in an industrial cold storage. Uniformly shaped and sized pork pieces were randomly selected and their initial mass m0 was measured.

[0030] S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 5.0mT and an oscillation frequency of 0.5Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:5. The low temperature environment is -20℃ and the relative humidity is 97%. The storage is carried out for 15 days, and the mass m1 of the sampled pork is measured.

[0031] After the experiment, the change in the pork juice loss rate was observed. The pork juice loss rate is calculated as (m0-m1) / m0×100%. Taking 10 pieces of pork, the juice loss rate was 0.82%. Assuming frozen pork costs approximately 20 yuan / kg, the cost of juice loss for 10 tons of pork would be around 1640 yuan.

[0032] Example 2: A method for preserving pork in a cold storage

[0033] A method for preserving pork in a cold storage facility includes the following steps:

[0034] S1. Raw material pretreatment: 10 tons of pork were placed in a pre-cooling warehouse to cool down to 4℃. The pork was then wrapped in plastic film, boxed, and stacked in an industrial cold storage. Uniformly shaped and sized pork pieces were randomly selected and their initial mass m0 was measured.

[0035] S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 5.0mT and an oscillation frequency of 0.5Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:5. The low temperature environment is -20℃ and the relative humidity is 90%. The storage is carried out for 15 days, and the mass m1 of the sampled pork is measured.

[0036] After the experiment, the change in the pork juice loss rate was observed. The pork juice loss rate is calculated as (m0-m1) / m0×100%. Ten pieces of pork were taken, and the juice loss rate was 1.06%, which is 29.27% ​​higher than the 0.82% in Example 1. The solution in Example 1 can save at least about 480 yuan compared to the solution in this example.

[0037] Example 3: A method for preserving pork in a cold storage

[0038] A method for preserving pork in a cold storage facility includes the following steps:

[0039] S1. Raw material pretreatment: 10 tons of pork were placed in a pre-cooling warehouse to cool down to 4℃. The pork was then wrapped in plastic film, boxed, and stacked in an industrial cold storage. Uniformly shaped and sized pork pieces were randomly selected and their initial mass m0 was measured.

[0040] S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 5.0mT and an oscillation frequency of 0.5Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:5. The low temperature environment is -20℃ and the relative humidity is 80%. The storage is carried out for 15 days, and the mass m1 of the sampled pork is measured.

[0041] After the experiment, the change in the pork juice loss rate was observed. The pork juice loss rate is calculated as (m0-m1) / m0×100%. Ten pieces of pork were taken, and the juice loss rate was 1.11%, which is 35.37% higher than the 0.82% in Example 1. The solution in Example 1 can save at least about 580 yuan compared to the solution in this example.

[0042] Comparative Example 1: The effect of direct cold storage on the preservation effect of pork

[0043] Using the same raw materials and pretreatment as in Example 1, the pork was stored in a cold storage environment at -20°C and 97% relative humidity for 15 days. After the cold storage period, 10 pieces of pork were sampled, and the juice loss rate was 2.69%, which is 228.05% higher than the 0.82% in Example 1. The solution in Example 1 can save at least 3740 yuan compared to this solution.

[0044] Comparative Example 2: The Effect of Different Magnetic Field Conditions on the Preservation Effect of Pork

[0045] During the invention process of this invention, the inventors discovered that setting different magnetic field conditions, such as magnetic field strength and type, has different effects on the preservation effect. Therefore, the inventors analyzed the influence of different magnetic field conditions on the preservation effect through single-factor optimization and other methods, and specifically provide the results of schemes 1-5 as follows.

[0046] Option 1: Compared with Example 1, the ratio of the interval time of the magnetic field in each interval cycle of S2 is adjusted to 1:1, and other conditions are the same as in Example 1.

[0047] Option 2: Compared with Example 1, the ratio of the interval time of the magnetic field in each interval cycle of S2 is adjusted to 1:6, and other conditions are the same as in Example 1.

[0048] Option 3: Compared with Example 1, the frequency of the oscillating magnetic field of S2 is adjusted to 2Hz, and other conditions are the same as in Example 1.

[0049] Option 4: Compared with Example 1, the intermittent periodic oscillating weak magnetic field in S2 is adjusted to a periodic constant weak magnetic field, specifically adjusted to a magnetic field strength of 5.0 mT, while other conditions remain the same as in Example 1.

[0050] Option 5: Compared with Example 1, the intermittent periodic oscillating weak magnetic field in S2 is adjusted to an intermittent constant weak magnetic field, specifically adjusted to a magnetic field strength of 10.0 mT, while other conditions remain the same as in Example 1.

[0051] The effects of different magnetic field environments on pork storage conditions were compared, and the results were compared with those of Example 1. The results are shown in Table 1. Table 1 shows that excessively high or low magnetic field parameters, such as magnetic field strength, interval period, and oscillation frequency, significantly affect the loss of juices during pork storage. Pork is rich in diamagnetic substances such as proteins and water molecules. Under a suitable external magnetic field, these substances orient themselves, causing rearrangement, cross-linking, and aggregation of macromolecules like myofibril proteins, forming ordered protein clusters. The hydrophobic interactions and hydration between proteins and water molecules are enhanced, effectively improving the water-holding capacity of pork. Furthermore, water molecules undergo spin polarization in a magnetic field, increasing their orderliness and effectively reducing the formation of large ice crystals, cell damage, and juice loss. However, when environmental and magnetic field parameters are excessively high or low, the secondary structure of proteins and hydrophobic interactions in pork change, altering the water distribution and reducing water-holding capacity. In summary, considering a storage volume of approximately 10 tons of frozen pork with a juice loss of about 20 yuan / kg, the optimal solution in Example 1 can save at least 480–3740 yuan compared to other solutions.

[0052] Table 1. Preservation effects of pork under different magnetic field environments

[0053] Option 1 1.87％ 128.05％ Option 2 2.03％ 147.56％ Option 3 1.59％ 93.90％ Option 4 1.22％ 48.78％ Option 5 1.54％ 87.80％

[0054] Example 4: A method for preserving chicken breast in a cold storage includes the following steps:

[0055] S1. Raw material pretreatment: Two tons of chicken breasts were placed in a pre-cooling warehouse to cool down to 4°C. The chicken breasts were then packaged in plastic film, boxed, and stacked in an industrial cold storage. Chicken breasts of uniform shape and size were randomly selected and their initial mass m0 was measured.

[0056] S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 3mT and an oscillation frequency of 0.5Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:3. The low temperature environment is -18℃ and the relative humidity is 98%. The storage is carried out for 30 days, and the mass m1 of the sampled chicken breast is measured.

[0057] After the experiment, the change in the juice loss rate of the chicken breast was observed. The juice loss rate of chicken breast = (m0-m1) / m0×100%. Ten chicken breasts were sampled, and the juice loss rate was 1.22%.

[0058] Example 5: A method for preserving chicken breast in a cold storage includes the following steps:

[0059] S1. Raw material pretreatment: Two tons of chicken breasts were placed in a pre-cooling warehouse to cool down to 4°C. The chicken breasts were then packaged in plastic film, boxed, and stacked in an industrial cold storage. Chicken breasts of uniform shape and size were randomly selected and their initial mass m0 was measured.

[0060] S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 3mT and an oscillation frequency of 0.5Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:3. The low temperature environment is -18℃ and the relative humidity is 90%. The storage is carried out for 30 days, and the mass m1 of the sampled chicken breast is measured.

[0061] After the experiment, the change in the juice loss rate of the chicken breast was observed. The juice loss rate of chicken breast is calculated as (m0-m1) / m0×100%. Ten chicken breasts were sampled, and the juice loss rate was 1.57%. Frozen chicken breast costs approximately 10 yuan / kg. With a storage volume of 2 tons, juice loss occurred. The solution in Example 4 saves 70 yuan compared to the solution in this example.

[0062] Example 6: A method for preserving chicken breast in a cold storage includes the following steps:

[0063] S1. Raw material pretreatment: Two tons of chicken breasts were placed in a pre-cooling warehouse to cool down to 4°C. The chicken breasts were then packaged in plastic film, boxed, and stacked in an industrial cold storage. Chicken breasts of uniform shape and size were randomly selected and their initial mass m0 was measured.

[0064] S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 3mT and an oscillation frequency of 0.5Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:3. The low temperature environment is -18℃ and the relative humidity is 80%. The storage is carried out for 30 days, and the mass m1 of the sampled chicken breast is measured.

[0065] After the experiment, the change in the juice loss rate of the chicken breast was observed. The juice loss rate of chicken breast is calculated as (m0-m1) / m0×100%. Ten chicken breasts were sampled, and the juice loss rate was 1.63%. Frozen chicken breast costs approximately 10 yuan / kg. With a storage volume of 2 tons, juice loss occurred. The solution in Example 4 saves 82 yuan compared to the solution in this example.

[0066] Comparative Example 3: The impact of conventional cold storage conditions on the preservation of chicken breast

[0067] Using the same raw materials and pretreatment as in Example 4, chicken was stored in a cold storage environment at -18°C and 98% relative humidity for 30 days. After the cold storage period, 10 chicken breasts were sampled, and the juice loss rate was 3.72%.

[0068] Comparative Example 4: The effect of storage conditions under different magnetic fields on the preservation of chicken breast

[0069] The inventors discovered that setting different magnetic field conditions, such as magnetic field strength and type, has different effects on the preservation effect of chicken breast. Therefore, the inventors analyzed the impact of different magnetic field conditions on the preservation effect of chicken breast using single-factor optimization and other methods, and specifically provide the results of schemes 1-5 below.

[0070] Option 1: Compared with Example 4, the ratio of the interval time of the magnetic field in each interval cycle of S2 is adjusted to 1:1, and other conditions are the same as in Example 4.

[0071] Option 23: Compared with Example 4, the ratio of the interval time of the magnetic field in each interval cycle of S2 is adjusted to 1:6, and other conditions are the same as in Example 4.

[0072] Option 3: Compared with Example 4, the frequency of the oscillating magnetic field of S2 is adjusted to 2Hz, and other conditions are the same as in Example 4.

[0073] Option 4: Compared with Example 4, the intermittent oscillating weak magnetic field in S2 is adjusted to an intermittent constant weak magnetic field, specifically adjusted to a magnetic field strength of 5.0 mT, while other conditions are the same as in Example 4.

[0074] Option 5: Compared with Example 4, the intermittent oscillating weak magnetic field in S2 is adjusted to an intermittent constant weak magnetic field, specifically adjusted to a magnetic field strength of 10.0 mT, while other conditions remain the same as in Example 4.

[0075] Table 2. Preservation effects of chicken breast under different storage conditions

[0076] Example 4 1.22％ - - Option 1 2.65％ 117.21％ 286 Option 2 2.94％ 140.98％ 344 Option 3 2.35％ 92.62％ 226 Option 4 1.88％ 54.10％ 132 Option 5 2.43％ 99.18％ 242

[0077] Table 2 shows that excessively high or low magnetic field parameters, such as magnetic field strength, interval period, and oscillation frequency, significantly affect the juice loss during chicken breast preservation. Chicken breast contains 74% water and 22% protein, which undergo orientation under a suitable external magnetic field. Chicken meat has poor fibrous tissue and water absorption, making it prone to juice loss after freezing and thawing. Under the influence of the magnetic field, large molecules such as myofibrillar proteins in the chicken meat undergo directional rearrangement, cross-linking, and aggregation, exposing more binding sites for hydrogen bonding, enhancing hydrophobic interactions and hydration with water molecules, increasing bound water content, and improving the water-holding capacity of the chicken breast. Simultaneously, during low-temperature freezing, the magnetic field promotes the formation of smaller, more rounded ice crystals, reducing mechanical damage to cell structures and minimizing juice loss. However, when environmental and magnetic field parameters are too high or too low, the secondary structure of proteins and hydrophobic interactions in the chicken breast change, altering water distribution and reducing water-holding capacity. Considering that frozen chicken breast costs approximately 10 yuan / kg and 2 tons experience juice loss, the scheme in Example 4 is the optimal solution.

[0078] It should be noted that the foregoing embodiments are merely illustrative examples of the present invention, and the various process conditions used are typical examples. However, after extensive testing and verification by the inventors of this case, the other process conditions listed above are also applicable and can achieve the technical effects claimed by the present invention.

[0079] It should be understood that the above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for preserving meat products in an industrial cold storage facility with a fixed weak magnetic field, characterized in that, The method involves storing meat products in a cold storage at a low temperature of -40 to 15°C, and providing a weak magnetic field to the environment in which the meat products are stored during the storage period; the weak magnetic field is an intermittent oscillating weak magnetic field. When the meat product is pork, methods for reducing juice loss during storage include: S1. Raw material pretreatment: Place the pork in a pre-cooling warehouse to cool it down to below 4°C, wrap the pork in plastic film and pack it into boxes, and then store it in stacks in an industrial cold storage. S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 5.0 mT and an oscillation frequency of 0.5 Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:

5. The low temperature environment is -20 ℃ and the relative humidity is 80~99%.

2. The method according to claim 1, characterized in that, The intermittent oscillating weak magnetic field is controlled by a weak magnetic field generating unit, which also includes an oscillating weak magnetic field power supply and a circuit control module.

3. The method according to claim 1, characterized in that, After the meat products are pre-cooled and stored at a uniform temperature, small samples are laid flat.

4. The method according to claim 1, characterized in that, The storage capacity of pork products ranges from 100kg to 300 tons.

5. A method for reducing juice loss during the storage of chicken breast, the method comprising: S1. Raw material pretreatment: Place the chicken breast in a pre-cooling warehouse to cool down to below 4°C, wrap the chicken breast in plastic film and pack it into boxes, then store it in stacks in an industrial cold storage. S2. Magnetic field cold storage: The cold storage adopts an intermittent oscillating weak magnetic field with a magnetic field strength of 3 mT and an oscillation frequency of 0.5 Hz. The ratio of the intermittent time of the magnetic field in each intermittent cycle is 1:

3. The low temperature environment is -18 ℃ and the relative humidity is 80~99%.