CN110195882B

CN110195882B - Thawing control method, thawing control device and computer storage medium

Info

Publication number: CN110195882B
Application number: CN201910309263.3A
Authority: CN
Inventors: 钟广雄; 黎青海; 周福昌; 马赤兵; 何春华
Original assignee: Midea Group Co Ltd; Guangdong Midea Kitchen Appliances Manufacturing Co Ltd
Current assignee: Midea Group Co Ltd; Guangdong Midea Kitchen Appliances Manufacturing Co Ltd
Priority date: 2019-04-17
Filing date: 2019-04-17
Publication date: 2021-10-08
Anticipated expiration: 2039-04-17
Also published as: CN110195882A

Abstract

The application discloses a thawing control method, a thawing control device and a computer storage medium, wherein the thawing control method comprises the following steps: performing first-stage thawing on food to be thawed at a first heating power until a first temperature rise of the food to be thawed in the first stage reaches a first temperature rise standard; performing second-stage thawing on the food to be thawed in an on-off mode at second heating power; the second stage of unfreezing is repeated until the second temperature rise of the food to be unfrozen in the last second stage reaches a second temperature rise standard; wherein the first heating power is greater than the second heating power. The thawing control method can achieve even heating thawing of food to be thawed.

Description

Thawing control method, thawing control device and computer storage medium

Technical Field

The present application relates to the field of thawing, and in particular, to a thawing control method, a thawing control device, and a computer storage medium.

Background

In daily life, food which is not eaten for a while, such as meat, is usually frozen for storage, and is thawed the next time the food is eaten. Usually, the natural thawing takes longer when the natural thawing is carried out in water or air.

Some household appliances such as a microwave oven have a thawing function at present, and can achieve quick thawing, however, the existing thawing process is easy to cause a problem of local overheating.

Disclosure of Invention

The application provides a thawing control method, a thawing control device and a computer storage medium, which are used for solving the problem that local overheating easily occurs in the existing food thawing process.

In order to solve the above technical problem, the present application provides a thawing control method, including: performing a first stage on food to be unfrozen at a first heating power until a first temperature rise of the food to be unfrozen in the first stage reaches a first temperature rise standard; performing second-stage thawing on the food to be thawed in an on-off mode at second heating power; the second stage of unfreezing is repeated until the second temperature rise of the food to be unfrozen in the last second stage reaches a second temperature rise standard; wherein the first heating power is greater than the second heating power.

In order to solve the above technical problem, the present application provides a thawing control device, including: a processor and a memory, the memory having stored therein a computer program, the processor being configured to execute the computer program to implement the steps of the above-described thawing control method.

In order to solve the above technical problem, the present application provides a computer storage medium having a computer program stored therein, the computer program being executed to implement the steps of the above-described thawing control method.

According to the unfreezing control method, firstly, food to be unfrozen is unfrozen at a first stage with larger first heating power until a first temperature rise of the food to be unfrozen at the first stage reaches a first temperature rise standard; then, carrying out second-stage unfreezing on the food to be unfrozen in an on-off mode with smaller second heating power; the unfreezing time of the first heating power is controlled through a first temperature rise standard, and an on-off type heating mode of the second heating power is adopted, so that the problem of local overheating is avoided; and repeating the second stage of unfreezing until the second temperature of the food to be unfrozen in the last second stage reaches a second temperature rise standard, and controlling the heating times of the second heating power according to the second temperature rise standard to avoid overheating. Based on this, this application unfreeze control method can realize the even heating unfreezing to food.

Drawings

FIG. 1 is a schematic flow chart diagram illustrating an embodiment of a thawing control method of the present application;

FIG. 2 is a schematic flow diagram illustrating details of an embodiment of the thaw control method of FIG. 1;

FIG. 3 is a schematic diagram of the temperature heat change during freezing of meat;

FIG. 4 is a schematic structural diagram of an embodiment of the thawing control system of the present application;

FIG. 5 is a schematic structural diagram of an embodiment of the thawing control device of the present application;

FIG. 6 is a schematic structural view of a microwave oven according to the present application;

FIG. 7 is a schematic structural diagram of an embodiment of a computer storage medium according to the present application.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, a thawing control method, a thawing control device and a computer storage medium provided by the present application are described in further detail below with reference to the accompanying drawings and the detailed description.

The unfreezing control device is adopted to unfreeze food, the frozen food can be heated and unfrozen to-2-35 ℃, and in the process of heating and unfreezing the food, the problem that the food is locally overheated due to uneven heating is easily caused, the food is required to be turned over at the moment, and the complexity of user operation is increased. The application provides the unfreezing control method, so that the food to be unfrozen can be uniformly heated and unfrozen, a user does not need to turn over the food in the unfreezing process, the unfreezing effect is enhanced, and the user operation is simplified.

Referring to fig. 1, fig. 1 is a schematic flow chart illustrating an embodiment of a thawing control method according to the present application. In the thawing control method of the embodiment, two-stage thawing is performed by using a first heating power and a second heating power respectively, wherein the first heating power is greater than the second heating power. The thawing control method includes the following steps.

S101: and performing first-stage thawing on the food to be thawed by using the first heating power until the first temperature rise of the food to be thawed in the first stage reaches a first temperature rise standard.

In this embodiment, the thawing may be performed by microwave heating or by heat pipe heating, so that the heating power may correspond to the output power of the heating element.

The first stage of thawing in this step is carried out with a first, higher heating power, which results in a high power of the ice breaking of the food to be thawed, e.g. in meat frozen at-18 c in a refrigerator, the freezing rate of water is about 90%, i.e. most of the water in the meat becomes ice crystals, but a small part of the water remains unfrozen. In the step, a small part of water is heated and charged by using a larger first heating power, and the thermal conductivity of the water is 0.582W/(m × k), the thermal conductivity of the ice is 2.326W/(m × k), and the thermal conductivity is about four times of that of the water, so that the small part of water can realize rapid heat transfer through the large part of ice after being charged, and the temperature rise is quicker at the stage.

However, if the heating is continued with the first heating power increased, some portions may be heated too quickly, and other portions may be in a frozen state, for example, the surface may be overheated, and the inside may be in a frozen state. Therefore, in the embodiment, the first-stage thawing is controlled by temperature rise, that is, when the first-stage thawing is performed, the first temperature rise of the food to be thawed is detected, and when the first temperature rise reaches the first temperature rise standard, the heating thawing is not performed at the first heating power, but the step S102 is performed, and the heating thawing is performed at the second smaller heating power.

S102: and carrying out second-stage thawing on the food to be thawed in an on-off mode at a second heating power.

When thawing is performed with a small second heating power, this embodiment is performed in an on-off manner. The food to be unfrozen is firstly conducted and heated and unfrozen with the second heating power, then the heating and unfreezing of the food to be unfrozen are stopped and suspended, and the overall balance of the temperature of the food to be unfrozen can be realized by the suspended heating process.

The second stage thawing is to avoid local overheating caused by too fast heating, so the heating time in the on-heating stage is also short. The second-stage thawing performed only once generally does not achieve complete thawing of the food, and thus the second-stage thawing of the on-off type at the second heating power is repeated a plurality of times in this embodiment.

S103: and repeating the second stage of unfreezing until the second temperature rise of the food to be unfrozen in the last second stage reaches the second temperature rise standard.

The repeated times of the second stage thawing are also controlled by the temperature rise, after the second stage thawing is finished each time, the second temperature rise of the food to be thawed in the second stage is calculated, and when the second temperature rise reaches the second temperature rise standard, the thawing is finished.

Different temperature rise changes can reflect that food is in different stages of unfreezing, after the unfreezing is completed, namely ice crystals are completely changed into water, the temperature rise of the water is increased, namely along with the gradual completion of the unfreezing, the temperature change of the second stage unfreezing is larger and larger, so that the second temperature rise standard is used for controlling, namely when the second temperature rise standard is reached, the unfreezing is considered to be completed, the ice crystals in the food are completely changed into water, and the temperature of the food reaches the expected unfreezing temperature.

In the embodiment, the ice is heated and broken by first heating power, and the first stage thawing is controlled by using a first temperature rise standard, so that local overheating is avoided; and then, second-stage unfreezing is repeatedly carried out through a second heating power on-off mode, the heating uniformity is ensured, and the second-stage unfreezing repetition times are controlled by utilizing a second temperature rise standard so as to control the unfreezing end. The first temperature-rise criterion and the second temperature-rise criterion are determined by the material of the food, and thus the present embodiment is not limited thereto.

Referring to fig. 2, fig. 2 is a detailed flowchart of an embodiment of the thawing control method shown in fig. 1. The thawing control method shown in fig. 2 specifically includes the following steps.

S201: the initial temperature of the food to be thawed is detected.

The initial temperature T of the food to be defrosted is detected when the food is placed in the defrosting device_sIn particular, it can be detected by a temperature sensor, for example an infrared sensor, provided in the thawing device itself. Temperature detection is also effected in a later step by means of the temperature sensor.

S202: and performing first-stage thawing on the food to be thawed with first heating power, and detecting the current temperature of the food to be thawed.

After the food to be defrosted is put into the defreezing device, the food is subjected to first-stage ice breaking and adding by first heating powerThermal thawing, first heating power p in the process₁May be 1000 w. In the process, the current temperature T of the food to be defrosted needs to be detected in real time_eI.e. periodically detecting the temperature of the food to be thawed.

S203: and calculating the difference value between the current temperature and the initial temperature to serve as a first temperature rise, and judging whether the first temperature rise reaches a first temperature rise standard.

After the current temperature is periodically detected and every time the current temperature is detected, the difference value between the current temperature and the initial temperature needs to be calculated, and the temperature rise of the food to be unfrozen when the current state is compared with the initial state, namely the first temperature rise delta T is obtained₁＝T_e-T_s。

After the first temperature rise is obtained, whether the first temperature rise reaches a first temperature rise standard dT is judged₁If yes, the first stage thawing is ended, and the process proceeds to step S204. If not, continuing the first-stage thawing, namely returning to the step S202, and continuing the first-stage thawing of the food to be thawed with the first heating power. When the embodiment is applied to unfreezing meat, the first temperature rise standard dT₁Is 4 ℃.

S204: and heating the food to be unfrozen at a second heating power.

After the first thawing phase is finished, the heating process is started with a second, lower heating power p₂And heating, wherein the heating time is such that the heating energy meets the preset energy requirement, and the heating energy is calculated by the second heating power and the heating time. In step S204, the food to be thawed can be heated at a lower second heating power with a fixed heating energy, so as to reduce the heating speed of the food to be thawed and avoid the problem of local overheating caused by heating focusing. In this embodiment, the second heating power p₂Set to 400 w.

The fixed heating energy can be set according to the material of the food, but the fixed heating energy of all the materials cannot be exhausted in the preset process, so the unit heating energy for the first-stage thawing is utilized in the embodiment.

Specifically, after the first stage thawing is completed, the calculation of the thawing waiting timeTotal heating energy Q consumed by food₁Can be calculated according to the first heating power; then according to the total heating energy Q₁And a first temperature rise DeltaT₁Calculating unit heating energy Δ Q ═ Q₁/△T₁. The fixed heating energy in step S204 may be equal to or less than the unit heating energy Δ Q.

S205: heating of the food to be thawed is suspended.

After the food to be thawed is provided with the fixed heating energy, the heating is suspended through the step S206, so that the overall temperature of the food to be thawed is balanced, and the heating is uniform. After the first stage unfreezing, more ice crystals still exist in the food to be unfrozen, so that the ice crystals transfer heat faster in the pause stage, the temperature of the food to be unfrozen falls back, namely, the temperature drops, and at the moment, heating energy needs to be provided in time for heating.

Therefore, in the present step S205, the pause time is required to meet the preset requirement, for example, the pause time meets the preset requirement that the temperature drop generated by the time is less than or equal to the preset temperature drop threshold, and if the pause time is greater than the temperature drop threshold and the thawing has not been finished, the heating energy is continuously provided to the food to be thawed through the step S204. Of course, a fixed time threshold may also be set as the pause time. The combination of the preset temperature drop threshold and the preset time threshold is adopted, the preset temperature drop threshold is adopted for control when the first few rounds of second-stage unfreezing are carried out, and the preset time threshold is adopted for control instead of the second few rounds of second-stage unfreezing which is about to end. The reason is that in the initial stage, more ice crystals exist in the food to be thawed, and in the later stage, fewer ice crystals exist and temperature drop basically does not occur any more; therefore, the former stage is determined by adopting a preset temperature drop threshold value, and the latter stage is determined by adopting a preset time threshold value. The front stage and the rear stage can be judged by temperature rise, the ice crystals in the front stage are mixed with water, the temperature rise is small, the ice crystals in the rear stage are small, and the temperature rise is large.

S206: and calculating a second temperature rise of the food to be unfrozen in the second stage, and judging whether the second temperature rise reaches a second temperature rise standard.

After the second stage of unfreezing is finished each time, calculating a second temperature rise of the food to be unfrozen, judging whether the second temperature rise meets a second temperature rise standard or not, and if so, indicating that the unfreezing is finished, thus finishing the unfreezing; if not, the second stage thawing is performed again, i.e. the process returns to step S204.

When the solid-liquid phase of the ice water changes, the temperature rises slowly, and when the solid-liquid phase of the ice water changes, the temperature rises quickly, and the detected temperature rise gradually increases, so that whether the thawing is completed can be judged by judging whether the second temperature rise reaches the second temperature rise standard in step S206.

In the embodiment, after the first-stage unfreezing is finished, the second-stage unfreezing is repeatedly carried out, so that local overheating is avoided, and the heating uniformity is ensured; and in the second stage of unfreezing, the temperature drop is utilized to control the heating pause time, so that the food to be unfrozen is supplemented with heating energy in time, and the heating and unfreezing efficiency of the food to be unfrozen is improved.

In this embodiment, the heating and thawing process is controlled by the temperature change and the heating energy change, and the whole thawing process is described in principle by taking meat as an example. Referring to fig. 3, fig. 3 is a schematic diagram of temperature and heat variation during the meat freezing process. The unfreezing process is the reverse process of the freezing process, so the control of the unfreezing process can be carried out by researching the freezing process. For example, to thaw meat, reference may first be made to the freezing process of meat as shown in fig. 3.

In the freezing process, the heat emitted by the meat is as follows:

Q＝m[c_p1(T₁-T_p)+wψr+c_p2(T_p-T₂)]

wherein Q is total heat release energy, m is meat mass, c_p1And c_p2Specific heat capacity before and after freezing meat, psi is freezing rate, r is latent heat of water forming ice, and T is₁、T_p、T₂Respectively, the initial temperature, the phase transition temperature and the final temperature. During freezing, meat heat release is mainly divided into three stages, namely a water heat release stage for cooling water but not freezing, a phase change heat release stage for converting water into ice, and a stage for continuously cooling ice after phase change conversion is completedAn ice heat release stage; as can be seen from fig. 3, the phase change heat release phase has the largest latent heat and the longest heat release time, and the temperature change is small in this phase, while the temperature change is large in the water heat release phase and the ice heat release phase. The heat release energy changes more uniformly throughout the freezing process.

The thawing process also has 3 endothermic phases corresponding to the freezing process. In the process of unfreezing meat, taking microwave unfreezing as an example, the microwave heating principle is as follows:

Q＝55.6×10^-12E²fvε″_r△t＝mc_p△T

wherein E is the electromagnetic field intensity, f is the microwave frequency, V is the volume, Delta T is the heating time, Delta T is the temperature rise, c_pIs specific heat capacity, ε_rIs the dielectric dissipation factor.

From this, a temperature rise slope k is obtained:

k＝△T/△t＝(55.6×10^-12E²fv/m)×(ε″_r/c_p)

the dielectric loss factor of water is much greater than that of ice, for example, the dielectric loss factor of ice at-13 ℃ is 0.0028, and the dielectric loss factor of water at 25 ℃ is 12.3; the specific heat capacity of the ice is half of that of the water, the specific heat capacity of the water is 4.2kJ/(kg x DEG C), and the specific heat capacity of the ice is 2.1kJ/(kg x DEG C); therefore, from the above formula of the temperature rise gradient k, k is obtained under the same heating power_{Water (W)}Is much greater than k_Ice。

Therefore, the ice thawing stage in the thawing process corresponds to the ice heat release stage of the freezing process, and at the moment, the meat contains a large amount of ice crystals and a small amount of water, so that the meat can be heated by a large first heating power, namely, the water inside the meat block is rapidly charged, and then rapid heat transfer is carried out through the ice with high thermal conductivity, so that the temperature rise in the stage is rapid.

When the temperature is raised to a certain temperature, the ice crystals in the meat gradually enter a solid-liquid phase change state, so that the heating power is adjusted to prevent local overheating, and the on-off heating and thawing with constant heating energy are carried out by adopting smaller second heating power.

The process comprises an ice water thawing stage, a phase change heat release stage corresponding to the freezing process, wherein the meat is heated in an on-off mode by using the heating energy of unit temperature rise of the ice thawing stage, more ice crystals still exist in the meat at the initial stage of the ice water thawing stage, the heat transfer in the meat is fast, the temperature falling condition is easy to occur after the heating, and therefore the energy supply is carried out on the meat blocks in time by monitoring the temperature falling.

The process also comprises a water thawing stage, a water heat-releasing stage corresponding to the freezing process, the same heating energy is supplied, the temperature of the meat blocks is slowly raised when the water is in an ice-water liquid phase, and the temperature of the meat blocks is rapidly raised after the meat blocks are completely converted into water, and the temperature rise is gradually increased. Therefore, the temperature rise after each on-off heating is recorded, and when the single temperature rise is larger than the second temperature rise standard, the unfreezing is finished. The second temperature rise criterion can be obtained by experiments.

Based on the principle of temperature energy change in the above thawing process, the present embodiment utilizes the temperature energy change to realize thawing control, and guarantees the uniformity and high efficiency of the thawing process. The thawing control method of the embodiment is specifically realized by hardware equipment and a software architecture.

From the perspective of software architecture, the present application further provides a thawing control system, please refer to fig. 4, where fig. 4 is a schematic structural diagram of an embodiment of the thawing control system of the present application. The thawing control system 100 of the present embodiment includes an energy statistics module 11, a temperature acquisition module 12, a data processing module 13, and a microwave control module 14.

The energy counting module 11 is used for counting heating energy in the heating and thawing process; the temperature acquisition module 12 is used for recording the temperature of food to be thawed; the data processing module 13 is used for processing the energy data and the temperature data to realize control; the microwave control module 14 is used for controlling the output power of the microwave.

Specifically, the data processing module 13 controls the microwave control module 14 to perform a first-stage thawing of a first heating power; acquiring a first temperature rise according to the temperature data acquired by the temperature acquisition module 12, judging whether the first temperature rise meets a first temperature rise standard, and if so, controlling the microwave control module 14 to perform second-stage thawing in a second heating power on-off mode; and in the second stage thawing process, the heating time, the pause time and the repetition times are controlled according to the temperature data collected by the temperature collecting module 12 and the energy data counted by the energy counting module 11. The details of the thawing control method are described above, and are not repeated.

Based on this control system 100 that unfreezes can carry out the control of unfreezing, realize even efficient heating unfreezing.

From the perspective of hardware devices, the present application provides a thawing control device, please refer to fig. 5, and fig. 5 is a schematic structural diagram of an embodiment of the thawing control device of the present application. The thawing control device 200 of the present embodiment includes a processor 21 and a memory 22.

Wherein the memory 22 stores therein a computer program, which the processor 21 is adapted to execute to implement the above-mentioned thawing control method. The processor 21 may be an integrated circuit chip having signal processing capabilities. The processor 21 may also be a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The thawing control device 200 may be a household appliance such as a microwave oven, an oven, a steam box, etc., and the food is placed in the thawing control device 200 to realize the thawing process; the food thawing device can be controlled by the control terminal, the food is placed in the thawing device which can be heated, the control terminal controls the thawing device to achieve the thawing process, and the control terminal can be intelligent household appliances such as a refrigerator and the like, and can also be control terminals such as a smart phone and wearable equipment. The control terminal and the unfreezing device can be in wireless connection.

The device for realizing defrosting in this embodiment may be a microwave oven, and the structure of the microwave oven can refer to fig. 6, and fig. 6 is a schematic structural diagram of the microwave oven of this application.

Wherein, the microwave oven 300 comprises a microwave oven cavity, a vessel for placing food, and an infrared temperature sensor detachably and fixedly arranged on the microwave oven cavity through a fixing buckle. The temperature of food can be acquired by the infrared temperature sensor, and the food temperature is generally acquired by averaging after multipoint temperature acquisition.

For the above logical processes of the thawing control method, the logical processes may exist in the form of a computer program, so that the present application provides a computer storage medium, please refer to fig. 7, where fig. 7 is a schematic structural diagram of an embodiment of the computer storage medium of the present application. The computer storage medium 400 of the present embodiment stores a computer program 41 that can execute the above-described thawing control method.

The computer storage medium 400 of this embodiment may be a medium that can store program instructions, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk, or may also be a server that stores the program instructions, and the server may send the stored program instructions to other devices for operation, or may self-operate the stored program instructions.

The above description is only for the purpose of illustrating embodiments of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings of the present application or are directly or indirectly applied to other related technical fields, are also included in the scope of the present application.

Claims

1. A thawing control method, characterized by comprising:

performing first-stage thawing on food to be thawed at first heating power until first temperature rise of the food to be thawed in the first stage reaches a first temperature rise standard;

performing second-stage thawing on the food to be thawed at a second heating power, wherein the heating time is such that the heating energy based on the second heating power and the heating time is less than or equal to unit heating energy, and the unit heating energy is the energy consumed by the food to be thawed for realizing unit temperature rise during the first stage thawing;

suspending heating of the food to be thawed;

repeating the second stage of unfreezing until the second temperature rise of the food to be unfrozen in the last second stage of unfreezing reaches a second temperature rise standard, wherein the pause time of the food to be unfrozen in the second stage before the preset sequence is enabled to be smaller than or equal to a preset temperature drop threshold value when the food to be unfrozen in the second stage is unfrozen, and the pause time of the food to be unfrozen in the second stage after the preset sequence reaches the preset time threshold value;

wherein the first heating power is greater than the second heating power.

2. The thawing control method according to claim 1, further comprising:

calculating the total heating energy consumed by the food to be unfrozen in the first stage according to the first heating power;

calculating the unit heating energy from the total heating energy and the first temperature rise.

3. The thawing control method according to claim 1, wherein the second-stage thawing of the food to be thawed is performed with the second heating power on/off, further comprising:

after the food to be unfrozen is suspended from being heated, calculating a second temperature rise of the food to be unfrozen in the second stage;

judging whether the second temperature rise reaches the second temperature rise standard or not;

in response to the second temperature rise meeting the second temperature rise criterion, ending thawing;

repeating the second stage thawing in response to the second temperature rise not meeting the second temperature rise criteria.

4. The thawing control method according to claim 1, wherein the first-stage thawing of the food to be thawed at the first heating power until a first temperature rise of the food to be thawed in the first stage reaches a first temperature rise criterion comprises:

detecting an initial temperature of the food to be unfrozen for starting a first-stage unfreezing and a current temperature for carrying out the first-stage unfreezing;

taking the difference value between the current temperature and the initial temperature as a first temperature rise;

judging whether the first temperature rise reaches a first temperature rise standard or not;

ending the first stage thawing in response to the first temperature rise meeting the first temperature rise criterion;

continuing the first stage thawing in response to the first temperature rise not meeting the first temperature rise criteria.

5. Thawing control device, characterized in that it comprises a processor and a memory, in which a computer program is stored, said processor being adapted to execute said computer program for implementing the steps of the method according to any of claims 1 to 4.

6. A computer storage medium, characterized in that the computer storage medium stores a computer program which is executed to implement the steps of the method of any one of claims 1-4.