Solid heat-conducting freshness preservation method based on phase change cooling

Abstract

A solid heat-conducting freshness preservation method based on phase change cooling. The method comprises the following steps: S1, on the basis of different food products to be subjected to freshness preservation, selecting cold storage materials having different phase change temperatures, and several metal cases used for storing the phase-change cold storage materials; S2, filling each metal case with a phase-change cold storage material, and sealing the metal cases to obtain several fully-enclosed metal phase-change crystal cells (2); S3, combining the plurality of metal phase-change crystal cells (2) in various ways so as to form a covering wrapping layer, comprising natural stacking of the metal phase-change crystal cells and assembly and processing of the metal phase-change crystal cells to prepare a freshness preservation carrier, wherein the freshness preservation carrier is configured to be in one of a net shape, an annular shape and a plate shape; and S4, in a freezer or a freshness preservation transport box, a metal cold plate being selectively placed at the bottom or a side surface thereof, and the cold plate being filled with a phase-change cold storage material. One or more of the stack of metal phase-change crystal cells, a freshness preservation carrier and a metal cold plate are combined to tightly wrap food products, phase change materials of the metal phase-change crystal cells or the metal cold plate release a large amount of cold energy by means of latent heat of phase change, and the cold energy is rapidly transferred to the food products by means of the metal cases, such that the food products quickly cross a crystallization zone, and a stable low-temperature environment is also provided for food storage and transport.

Description

A solid heat conduction preservation method based on phase change cooling Technical field:

[0001] The present invention belongs to the technical field of food preservation, and in particular relates to a solid heat conduction high-quality preservation method based on phase change cooling. Background technology:

[0002] Traditional food processing, transportation and storage mostly use air cooling, but its cooling speed is slow, the temperature fluctuates greatly, the crystal particles inside the food are large, puncturing the cell walls, causing the loss of liquid and the decline of nutrition, the taste deteriorates, and affects the quality of food. Low-cost and high-quality preservation is an urgent need for the development of the cold chain industry.

[0003] Rapid cooling is an important means of preserving high-quality food. The faster the food is cooled, the easier it is to pass through the crystallization temperature zone (-1 to -5°C), thereby preventing ice crystals from growing too large and piercing the cell walls, ensuring the integrity and activity of the cells, and thus improving the high quality of food preservation.

[0004] Traditional high-quality preservation methods usually use ultra-low temperature liquid nitrogen cooling, cryogenic immersion liquid cooling, and ice pack cooling. However, these preservation methods still have the following disadvantages:

[0005] Ultra-low temperature liquid nitrogen has a fast cooling speed and a good preservation effect, but it is extremely expensive and can easily cause food to dry out and crack, so it cannot be widely promoted.

[0006] Immersion liquid cooling: Fast cooling speed and good preservation effect, but high cost, large coolant loss, difficult to handle waste coolant, inconvenient operation, difficult to meet user needs;

[0007] Ice pack cooling: Ice packs conduct heat poorly and lack close contact with food, resulting in slow cooling and poor preservation. Ice packs are also prone to breakage, making them difficult to reuse or recycle, and can cause significant environmental pollution after disposal.

[0008] Based on the above defects, which affect the preservation effect and cost of food, we need to propose a solid thermal conduction preservation method based on phase change cooling for improvement, and propose a new preservation method that can achieve low cost, rapid cooling by solid thermal conduction, long-term recycling, and environmentally friendly, so as to improve the preservation effect of food.

[0009] Summary of the invention:

[0010] The purpose of the present invention is to provide a solid thermal conduction preservation method based on phase change cooling, which utilizes highly thermally conductive, recyclable metal phase change units to achieve rapid and low-cost cooling of food, significantly improving the food preservation effect, and solving the problems raised in the above-mentioned background technology.

[0011] To achieve the above object, the present invention adopts the following technical solutions:

[0012] A solid heat conduction preservation method based on phase change cooling, comprising the following steps:

[0013] S1. Selecting cold storage materials with different phase change temperatures and a plurality of metal shells for storing the phase change cold storage materials according to different foods to be preserved;

[0014] S2, filling the interior of each metal shell with a phase change cold storage material, and sealing the metal shell to obtain a plurality of fully enclosed metal phase change unit cells (2);

[0015] S3, combining the plurality of metal phase change cells (2) in a variety of ways to form a covering layer, including naturally stacking the metal phase change cells and assembling and processing the metal phase change cells to form a fresh-keeping carrier; the fresh-keeping carrier is configured to be in one of a mesh, annular, and plate shape;

[0016] S4. Metal cold plates filled with phase-change cold storage material can be placed at the bottom or side of a freezer or fresh-keeping transport box. Food can be tightly wrapped using one or more combinations of metal phase-change unit cells, fresh-keeping carriers, and metal cold plates. The phase-change material in the metal phase-change unit cells or metal cold plates releases a large amount of cold energy through latent heat of phase change, and quickly transfers the cold energy to the food through the metal shell, allowing it to quickly cross the crystallization zone, while providing a stable low-temperature environment for food storage and transportation.

[0017] Preferably, in step S1, the phase-change cold storage material is a mixture of one or more of alcohol, salt, glycerol, fatty acid, acetic acid, alkali, and alcohol solution.

[0018] Preferably, in step S3, the metal phase change unit cells include a combination of one or more sizes, and the contact area with the food is increased by matching the combination of metal phase change unit cells of different sizes.

[0019] Preferably, in step S4, the fresh-keeping carrier and the metal phase change unit cell can be used in combination. After the fresh-keeping carrier wraps the food, the metal phase change unit cell is directly filled in the inside or outside of the food that does not contact the fresh-keeping carrier, further increasing the contact area between the metal phase change unit cell and the food.

[0020] Preferably, the metal shell can be processed and formed by one of the processing techniques of extrusion, die casting and CNC machine tools, the metal shell is made of one of the materials of aluminum, copper, stainless steel, galvanized sheet and metal alloy, and the metal phase change unit cell is a polyhedron, sphere or cylinder.

[0021] Preferably, in step S3, a plurality of metal phase change unit cells are processed into a fresh-keeping carrier with an annular structure, and two adjacent metal phase change unit cells are connected by a hinge or an elastic material.

[0022] Preferably, the metal phase change unit cells (2) can be connected in pairs by flexible materials or elastic materials to form a fresh-keeping carrier with a node network structure, and the metal phase change unit cells serve as nodes and are connected in pairs with the surrounding phase change unit cells to form a flexible plane.

[0023] Preferably, the metal phase change unit cell is configured as a cylindrical or prismatic structure, and the fresh-keeping carrier includes a support plate, and grooves are provided on opposite sides of the support plate, and a plurality of metal phase change unit cells are slidably inserted in the grooves, and the plurality of metal phase change unit cells are arranged in a rectangular array.

[0024] Preferably, the metal phase change unit cell includes a rod body and end bodies located at both ends of the rod body, the end bodies are configured as spheres or polyhedrons, the end bodies and the rod body are integrally formed, and the interiors of the end bodies and the rod body are both provided with cavities for filling with phase change cold storage material, and the support plate is provided with a through hole for the rod body to slide through, and the diameter of the through hole is smaller than the diameter of the end body.

[0025] The solid heat conduction preservation method based on phase change cooling proposed in the present invention has the following advantages over the prior art:

[0026] 1. The present invention encapsulates the cold storage material in a highly thermally conductive metal shell. Utilizing the characteristics of stacking metal phase change cells or the flexible adjustment of the preservation carrier, the metal phase change cells are brought into close contact with the food. The phase change material in the metal phase change cells releases a large amount of cold through the latent heat of phase change, and the heat is conducted by the metal shell to quickly lower the temperature of the food, quickly crossing the crystallization zone, while providing a stable low-temperature environment for food processing, storage, and transportation, thereby achieving the effect of high-quality, long-term preservation.

[0027] 2. The fresh-keeping carrier provided by the present invention can be recycled and reused for a long time, which reduces the cost of food preservation, does not generate waste during use, and has good environmental protection characteristics.

[0028] 3. The present invention adopts food-grade metal shell and phase change material, which does not pollute food and ensures the health and safety of food.

[0029] 4. The present invention uses metal phase change cells or processed fresh-keeping carriers which are very convenient to use, do not require professional operation, and do not have complicated processes. They can be applied to food processing, transportation and storage for home or commercial use, and have a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG1 is a system block diagram of the present invention;

[0031] FIG2 is a schematic structural diagram of a fresh-keeping carrier in Example 1 of the present invention;

[0032] FIG3 is a schematic structural diagram of a fresh-keeping carrier in Example 6 of the present invention;

[0033] FIG4 is a schematic structural diagram of a fresh-keeping carrier in Example 7 of the present invention;

[0034] FIG5 is a schematic diagram of a metal phase change unit cell structure in Example 7 of the present invention;

[0035] FIG6 is a schematic structural diagram of a food trough in Example 7 of the present invention;

[0036] FIG7 is a schematic diagram of the natural stacking of metal phase change cells for food preservation in Example 1 of the present invention;

[0037] FIG8 is a schematic diagram of food preservation when a metal cold storage plate is combined with a plurality of metal phase change cells in Example 1 of the present invention;

[0038] FIG9 is a schematic diagram of a mesh fresh-keeping carrier in Example 1 of the present invention;

[0039] FIG10 is a schematic diagram of the metal cold storage plate and the multi-layer fresh-keeping carrier in Example 1 of the present invention when preserving food.

[0040] In the figure: 1. support plate; 2. metal phase change unit cell; 21. rod body; 22. end body; 3. groove; 4. connecting buckle; 5. food trough; 6. food. Specific implementation method:

[0041] 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 embodiments described are only part of the embodiments of the present invention, not all of the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0042] Example 1

[0043] The present invention provides a solid heat conduction preservation method based on phase change cooling as shown in FIG1-2 , comprising the following steps:

[0044] S1. Selecting cold storage materials with different phase change temperatures and a plurality of metal shells for storing the phase change cold storage materials according to different foods to be preserved;

[0045] The phase-change cold storage material is a mixture of one or more of alcohol, salt, glycerol, fatty acid, acetic acid, alkali, and alcohol solution.

[0046] The metal shell can be processed and formed by extrusion, die casting and CNC machine tool processing.

[0047] The metal shell is made of one of aluminum, copper, stainless steel, galvanized sheet and metal alloy.

[0048] Among them, metal alloys generally include aluminum alloys, copper alloys and some specific types of metal alloys, and have good thermal stability and mechanical strength.

[0049] Furthermore, when selecting the metal shell material, the chemical properties of the phase change material must be considered to ensure it can withstand the chemical reactions that may occur during the phase change. For example, if the phase change material is corrosive in its molten state, the encapsulation material must have sufficient corrosion resistance to withstand this corrosion. Cost and processing techniques must also be considered to ensure that the selected material is both economical and easy to process into the desired shape.

[0050] S2, filling the interior of each metal shell with a phase change cold storage material and sealing the metal shell to obtain a plurality of fully enclosed metal phase change unit cells 2;

[0051] The metal phase change unit cell 2 has a polyhedron, a sphere or a cylinder shape.

[0052] S3. Combine multiple metal phase change cells 2 in a variety of ways to form a covering wrapping layer, including natural stacking of metal phase change cells and assembly and processing of metal phase change cells into a fresh-keeping carrier; the fresh-keeping carrier is set to one of a mesh, ring and plate shape; as shown in Figure 7, it is a schematic diagram of the natural stacking of metal phase change cells for food preservation. When natural stacking is adopted, the metal phase change cells can also be wrapped in a flexible mesh and stacked to cover the surrounding of the food; Figure 8 is a schematic diagram of the combination of a metal cold storage plate and multiple metal phase change cells for food preservation; Figure 9 is a schematic diagram of a mesh fresh-keeping carrier; Figure 10 is a schematic diagram of the metal cold storage plate and a multi-layer fresh-keeping carrier for food preservation.

[0053] A plurality of metal phase change cells 2 are processed into a fresh-keeping carrier with a ring structure, and two adjacent metal phase change cells 2 are connected by hinges or elastic materials. When preserving food, the fresh-keeping carrier is put on the food to be preserved, such as the outside of fish or chicken legs. The fresh-keeping carrier can tightly wrap the food, and the phase change cold storage material in the metal phase change cell 2 is used to absorb the heat in the food. In addition, the fresh-keeping carrier can be recycled and used to avoid one-time loss, thereby reducing the cost of food preservation to a certain extent.

[0054] S4. Metal cold plates filled with phase-change cold storage materials can be placed on the bottom or sides of freezers or fresh-keeping transport boxes. Food is tightly wrapped using one or more combinations of metal phase-change stacks, fresh-keeping carriers, and metal cold plates. The phase-change materials in the metal phase-change cells or metal cold plates release a large amount of cold energy through latent heat of phase change, and the cold energy is quickly transferred to the food through the metal shell, allowing it to quickly cross the crystallization zone, while providing a stable low-temperature environment for food storage and transportation.

[0055] Example 2

[0056] The similarities are not repeated here. The difference from Example 1 is that in step S3, the metal phase change unit cells include a combination of one or more sizes, and the contact area with the food is increased by matching the combination of metal phase change unit cells of different sizes.

[0057] Example 3

[0058] The similarities are not repeated here. The difference from Example 1 is that in step S4, the fresh-keeping carrier and the metal phase change unit cell can be used in combination. After the fresh-keeping carrier wraps the food, the metal phase change unit cell is directly filled in the inside or outside of the food that does not contact the fresh-keeping carrier, thereby further increasing the contact area between the metal phase change unit cell and the food. For example, after a whole chicken is wrapped with a fresh-keeping carrier, the chicken part can be filled with the metal phase change unit cell, and the metal phase change unit cell and the fresh-keeping carrier are used to increase the contact area with the chicken, thereby increasing the effect of preserving the chicken.

[0059] Example 4

[0060] The similarities will not be repeated. The difference from Example 1 is that the metal phase change cells 2 can be connected in pairs through flexible materials or elastic materials to form a fresh-keeping carrier with a node network structure. The metal phase change cells serve as nodes and are connected in pairs with the surrounding phase change cells to form a flexible plane, which is suitable for close contact with the surface of food with irregular surfaces.

[0061] Example 5

[0062] The similarities are not repeated here. The difference from Example 1 is that, as shown in FIG3 , the fresh-keeping carrier is a stretchable metal ring made of a plurality of metal phase change cells 2. The metal ring is provided with a connecting buckle 4 that can open or connect the metal ring. The metal ring is sleeved on the arc-shaped food, and the phase change cold storage material in each metal phase change cell 2 in the metal ring is used to absorb the heat in the food. The metal belt is opened conveniently by opening and closing the connecting buckle 4, so that the metal belt can easily pass through the food and tightly wrap around the outside of the food, and the phase change cold storage material in the metal phase change cell 2 is used to absorb the heat in the food.

[0063] Example 6

[0064] The similarities are not repeated here. The difference from Example 1 is that, as shown in Figures 4-6, the metal phase change unit cell 2 is configured as a cylindrical or prismatic structure, and the fresh-keeping carrier includes a support plate 1, and grooves 3 are provided on opposite sides of the support plate 1. A plurality of metal phase change unit cells 2 are slidably inserted in the grooves 3, and the plurality of metal phase change unit cells 2 are arranged in a rectangular array. When preserving food, the food is placed on the plurality of metal phase change unit cells 2, and the elastic structure is used to make the surface of the food in close contact with the metal phase change unit cells 2 and move toward the side away from the food, so that the plurality of metal phase change unit cells 2 in the groove 3 form a food groove 5 that is stably fitted with the shape of the food. At this time, the metal phase change unit cells around the food and the edge of the food groove 5 are in close contact with each other. The side walls of the cell 2 are in contact with the food, and the food is in contact with the metal phase change cell 2 in the food trough 5, thereby increasing the number of metal phase change cells 2 in contact with the food, and utilizing the phase change cold storage material in the metal phase change cell 2 to absorb the heat of the food. By setting up a number of metal phase change cells 2 made of metal materials, the food trough 5 can be flexibly prepared according to the food of different shapes. When preparing the food trough 5, the food is placed on a plurality of metal phase change cells 2, and a pressure plate is placed on the side of the food away from the metal phase change cell 2. The pressure plate is pressed to push the metal phase change cell 2 located below the food to move, so that the food placed in the food trough 5 can be fully fitted with the metal phase change cell 2 and wrap the food, thereby ensuring that the food can fully fit the phase change material within a certain range.

[0065] The metal phase change unit cell 2 includes a rod body 21 and end bodies 22 located at both ends of the rod body 21. The end bodies 22 are configured as spheres or polyhedrons. The end bodies 22 and the rod body 21 are integrally formed. The interiors of the end bodies 22 and the rod body 21 are both provided with cavities for filling with phase change cold storage materials. A through hole is provided on the support plate 1 for the rod body 21 to slide through, and the diameter of the through hole is smaller than the diameter of the end body 22. The rod body 21 can be configured as a hexagonal prism or a cylinder. The through hole is matched with the rod body 21, so that the metal phase change unit cell 2 can have a certain movement space in the groove 3, and the movement direction of the metal phase change unit cell 2 is perpendicular to the installation direction of the support plate 1. The length of the rod body 21 is greater than the thickness of the support plate 1, which is convenient for flexibly preparing the food trough 5 according to the shape of the food.

[0066] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A solid heat conduction preservation method based on phase change cooling, characterized in that: The steps include: S1. Selecting cold storage materials with different phase change temperatures and a plurality of metal shells for storing the phase change cold storage materials according to different foods to be preserved; S2, filling each metal shell with a phase change cold storage material, and sealing the metal shell to obtain a plurality of fully enclosed metal phase change unit cells (2); S3, combining the plurality of metal phase change cells (2) in a variety of ways to form a covering wrapping layer, including naturally stacking the metal phase change cells, assembling and processing the metal phase change cells to form a fresh-keeping carrier; the fresh-keeping carrier is configured to be one of a mesh, a ring, and a plate; S4. In the freezer or fresh-keeping transport box, a metal cold plate can be placed at the bottom or side, and the cold plate is filled with phase-change cold storage materials. The food is tightly wrapped with one or more combinations of metal phase-change crystal cells, fresh-keeping carriers and metal cold plates. The phase-change materials of the metal phase-change crystal cells or metal cold plates release a large amount of cold through the latent heat of phase change, and quickly transfer the cold to the food through the metal shell, so that it quickly crosses the crystallization zone, while providing a stable low-temperature environment for food storage and transportation.

2. A solid heat conduction preservation method based on phase change cooling according to claim 1, characterized in that: In step S1, the phase change cold storage material is set to be a mixture of one or more of alcohol, salt, glycerol, fatty acid, acetic acid, alkali, and alcohol solution.

3. The solid heat conduction preservation method based on phase change cooling according to claim 1, characterized in that: In step S3, the metal phase change unit cells include a combination of one or more sizes, and the contact area with the food is increased by matching the combination of metal phase change unit cells of different sizes.

4. The solid heat conduction preservation method based on phase change cooling according to claim 1, characterized in that: In step S4, the fresh-keeping carrier and the metal phase change unit cell can be used in combination. After the fresh-keeping carrier wraps the food, the metal phase change unit cell is directly filled in the inside or outside of the food that does not contact the fresh-keeping carrier, further increasing the contact area between the metal phase change unit cell and the food.

5. The solid heat conduction preservation method based on phase change cooling according to claim 1, characterized in that: The metal shell can be processed and formed by one of the processing techniques of extrusion, die casting and CNC machine tools. The metal shell is made of one of the materials selected from the group consisting of aluminum, copper, stainless steel, galvanized sheet and metal alloy. The metal phase change unit cell (2) is in the shape of a polyhedron, a sphere or a cylinder.

6. A solid heat conduction preservation method based on phase change cooling according to claim 5, characterized in that: In step S3, a plurality of metal phase change cells (2) are processed into a fresh-keeping carrier with an annular structure, and two adjacent metal phase change cells (2) are connected via a hinge or an elastic material.

7. The solid heat conduction preservation method based on phase change cooling according to claim 5, characterized in that: The metal phase change crystal cells (2) can be connected in pairs through flexible materials or elastic materials to form a fresh-keeping carrier with a node network structure. The metal phase change crystal cells serve as nodes and are connected in pairs with surrounding phase change crystal cells to form a flexible plane.

8. The solid heat conduction preservation method based on phase change cooling according to claim 5, characterized in that: The metal phase change unit cell (2) is arranged in a cylindrical or prismatic structure, and the fresh-keeping carrier comprises a support plate (1), and grooves (3) are provided on opposite sides of the support plate (1), and a plurality of metal phase change unit cells (2) are slidably inserted in the grooves (3), and the plurality of metal phase change unit cells (2) are arranged in a rectangular array.

9. A solid heat conduction preservation method based on phase change cooling according to claim 8, characterized in that: The metal phase change unit cell (2) comprises a rod body (21) and end bodies (22) located at both ends of the rod body (21); the end bodies (22) are arranged as spheres or polyhedrons; the end bodies (22) and the rod body (21) are arranged in an integral manner; cavities for filling phase change cold storage material are arranged inside the end bodies (22) and the rod body (21); a through hole for the rod body (21) to slide through is opened on the support plate (1); and the diameter of the through hole is smaller than the diameter of the end body (22).

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