A refrigerator for food preservation and a method for food preservation

Abstract

This invention provides a refrigerator and a method for preserving fresh meat. The refrigerator includes a display, a controller, and a temperature-controlled variable-temperature zone. The variable-temperature zone is used for storing fresh meat. An electric field generating device is provided in the variable-temperature zone to apply an electric field to the zone. The controller is configured to: acquire a user-inputted preservation command; when the preservation command is for the meat maturation stage, preserve the meat according to a first preservation condition; when the preservation command is for the meat fresh storage stage, preserve the meat according to a second preservation condition; and when the preservation command is for the ordinary storage stage, preserve the meat according to a third preservation condition. This application adjusts the refrigerator's fresh meat storage conditions according to the user-inputted preservation command, ensuring the meat is stored under suitable conditions, which is conducive to the maturation of the meat and extends the maturation time. Furthermore, by rationally setting the storage structure, the fresh meat storage effect is improved, and the refrigerator's storage space layout is optimized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of refrigerators, in particular to a fresh-keeping refrigerator and a fresh-keeping method. BACKGROUND

[0002] In the field of food, the umami of meat products is of great concern. As an important sensory characteristic of meat products and a key indicator for people to evaluate the quality of meat products, it has an important influence on the dining experience of consumers. The umami substances contained in meat products, such as amino acids, nucleotides, and polypeptides, have become a research hotspot in the field of food umami science because they have the characteristics of improving food flavor and enhancing people's appetite. However, in actual situations, factors such as the storage temperature, storage humidity, environmental field strength of meat products, and the variety and muscle type of meat can cause the umami of meat products to change to varying degrees. In order to preserve the umami of meat products as much as possible during storage and maximize the umami, it is necessary to adjust the corresponding storage environment conditions according to the characteristics of different varieties of meat. Considering that the ripening time, protein hydrolysis into umami substances, and the retention time of umami substances are different for different varieties of meat, the storage conditions and optimal storage time of different varieties of fresh meat are different.

[0003] Currently, refrigerators are commonly used on the market to store fresh meat. Refrigerators can create a low-temperature environment through a refrigeration system, which can slow down the deterioration of meat products to some extent and provide a relatively stable space for meat preservation. In addition, some refrigerators have certain temperature and humidity adjustment functions, which can control the temperature and humidity of the internal environment within a certain range.

[0004] Although the existing refrigerator has certain storage and environment adjustment functions, it cannot accurately set the corresponding storage conditions for different varieties of fresh meat according to the user's needs, and it is difficult to both facilitate the ripening of fresh meat and extend the time of maintaining the ripened state. It cannot well meet the differentiated needs of different varieties of fresh meat in storage, and thus has obvious deficiencies in ensuring the important quality of meat umami, and cannot fully meet people's expectations for the maximum preservation of meat umami. SUMMARY

[0005] The present application provides a fresh-keeping refrigerator and a fresh-keeping method to solve the problem that the existing technology cannot accurately set the corresponding storage conditions for different varieties of fresh meat according to the user's needs, and it is difficult to both facilitate the ripening of fresh meat and extend the time of maintaining the ripened state. It cannot well meet the differentiated needs of different varieties of fresh meat in storage.

[0006] In a first aspect, the present application provides a fresh-keeping refrigerator, which comprises:

[0007] a display, a controller, and a temperature-independent variable-temperature zone; the variable-temperature zone is used for storing fresh meat;

[0008] An electric field generating device for applying an electric field to the temperature-changing zone is provided within the temperature-changing zone.

[0009] The variable temperature zone is also equipped with temperature and humidity sensors;

[0010] The controller is configured to:

[0011] Obtain the user's input instructions for food preservation;

[0012] When the preservation instruction is for the fresh meat maturation stage, the fresh meat is preserved according to the first preservation condition;

[0013] When the preservation instruction is for the fresh meat preservation stage, the fresh meat shall be preserved in accordance with the second preservation conditions;

[0014] When the preservation instruction is in the normal storage stage, the fresh meat is preserved according to the third preservation condition; wherein, the storage temperature of the first preservation condition is greater than the storage temperature of the second preservation condition, which is greater than the storage temperature of the third preservation condition.

[0015] In some possible implementations, the controller is also configured to:

[0016] When the preservation instruction is for the fresh meat maturation stage, a timer is also started to record the preservation time;

[0017] When the preservation time exceeds the first threshold, the fresh meat is preserved according to the second preservation conditions; wherein the timer remains on.

[0018] When the preservation time exceeds the second threshold, the fresh meat is preserved according to the third preservation condition, and the timer is turned off; the first threshold is 72h, and the second threshold is 30d.

[0019] In some possible implementations, the second preservation condition includes short-term storage and long-term storage, and further includes the condition when the preservation time exceeds a first threshold:

[0020] When the preservation time exceeds the first threshold but is less than the third threshold, the fresh meat is preserved according to the short-term storage in the second preservation condition;

[0021] If the preservation time exceeds the third threshold but is less than the second threshold, the fresh meat shall be stored in accordance with the long-term storage in the second preservation conditions.

[0022] If the preservation time exceeds the second threshold, the fresh meat is preserved according to the third preservation conditions, and the timer is turned off; the third threshold is 15 days, the short-term storage temperature is -5℃ to 0℃, and the long-term storage temperature is -16℃ to -32℃.

[0023] In some possible implementations, the first preservation conditions include: a temperature of 0–4°C, a humidity of 50–80%, and an electric field strength of 50–2000 V / m.

[0024] In some possible implementations, the second preservation conditions include short-term storage and long-term storage; wherein, the short-term storage temperature is -5 to 0°C, the humidity is 30 to 80%, and the electric field strength is 500 to 2000 V / m; the long-term storage temperature is -16°C to -32°C, the humidity is 30 to 80%, and the electric field strength is 500 to 2000 V / m.

[0025] In some possible implementations, the third preservation conditions include: a temperature of -18 to -20°C, a humidity of 20 to 80%, and an electric field strength of 500 to 3000 V / m.

[0026] In some possible implementations, the temperature adjustable range of the independently temperature-controlled variable temperature zone is -32℃ to 5℃.

[0027] In some possible implementations, the drawer of the variable temperature zone includes an upper tray and a lower drawer. The upper tray is designed to be concave, with sloping side walls on all four sides, and evenly distributed holes on the sloping sides. The upper tray and the lower drawer are combined to form a sealed cavity, and the sloping holes of the upper tray are within the opening frame of the lower drawer. The air outlet of the variable temperature zone is located on the upper end of the upper tray on the rear wall of the zone.

[0028] In some possible implementations, the electric field generating device includes an electric field generating end and an electric field releasing end, wherein the electric field generating end is installed on any side of the refrigerator top cover or compressor compartment, and the electric field releasing end is installed at any location on the side wall, bottom surface or top wall of the variable temperature zone. The voltage of the electric field generating end is 200V or 12V, and the frequency is 0.5 to 100KHz.

[0029] Secondly, this application also provides a method for preserving food, the method comprising:

[0030] Obtain the user's input instructions for food preservation;

[0031] When the preservation instruction is for the fresh meat maturation stage, the fresh meat is preserved according to the first preservation condition;

[0032] When the preservation instruction is for the fresh meat preservation stage, the fresh meat shall be preserved in accordance with the second preservation conditions;

[0033] When the preservation instruction is in the normal storage stage, the fresh meat is preserved according to the third preservation condition; wherein, the storage temperature of the first preservation condition is greater than the storage temperature of the second preservation condition, which is greater than the storage temperature of the third preservation condition.

[0034] As described above, this application provides a refrigerator and a method for preserving fresh meat. The refrigerator includes a display, a controller, and an independently temperature-controlled variable-temperature zone. The variable-temperature zone is used for storing fresh meat. An electric field generating device for applying an electric field to the variable-temperature zone is provided within the variable-temperature zone. A temperature and humidity sensor is also provided within the variable-temperature zone. The controller is configured to: acquire a user-inputted preservation command; when the preservation command is for the meat maturation stage, preserve the fresh meat according to a first preservation condition; when the preservation command is for the meat fresh storage stage, preserve the fresh meat according to a second preservation condition; and when the preservation command is for the ordinary storage stage, preserve the fresh meat according to a third preservation condition. This application adjusts the refrigerator's fresh meat storage conditions according to the user-inputted preservation command, ensuring that the fresh meat is stored under suitable conditions, which is conducive to the maturation of the fresh meat and extends the maturation time. On the other hand, by rationally setting the storage structure, the fresh meat storage effect is improved, and the refrigerator's storage space layout is optimized. Attached Figure Description

[0035] To more clearly illustrate the technical solution of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the structure of the variable temperature zone in a refrigerator provided in an embodiment of this application;

[0037] Figure 2 A flowchart of a preservation method provided in an embodiment of this application;

[0038] Figure 3 This is a diagram showing the factors influencing the electric field in Embodiment 1 of this application;

[0039] Figure 4 This is a diagram showing the factors affecting the cooling rate in Embodiment 2 of this application.

[0040] Illustration: 1-Upper tray; 2-Lower drawer. Detailed Implementation

[0041] The embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described below do not represent all embodiments consistent with this application. They are merely examples of systems and methods consistent with some aspects of this application as detailed in the claims.

[0042] In the food industry, the umami flavor of meat is of great interest. As an important sensory characteristic of meat and a key indicator for evaluating meat quality, it has a significant impact on consumers' dining experience. Umami substances in meat, such as amino acids, nucleotides, and polypeptides, have become a research hotspot in the field of food umami science due to their ability to improve food flavor and enhance appetite. The main source of umami substances is free amino acids, primarily glutamic acid and aspartic acid. Amino acids are the basic molecules that make up proteins. When amino acids exist as proteins, they cannot release umami flavor; protein hydrolysis is required to release them and produce umami. The synergistic effect of various flavor-enhancing amino acids is an important factor in the formation of food flavor. Flavor-enhancing nucleotides combine better with umami amino acids to produce a synergistic effect, resulting in a richer umami flavor. When foods rich in glutamic acid combine with components containing nucleotides, the resulting flavor intensity is higher than the combined intensity of these components.

[0043] In reality, many factors, such as storage temperature, humidity, environmental field strength, and meat variety and muscle type, can cause varying degrees of change in the umami flavor of meat. During the aging process, meat is decomposed by proteases and microorganisms, increasing the content of umami substances such as free amino acids. Enzymes and microorganisms are greatly affected by temperature and humidity. Within a certain range, higher temperature and humidity can enhance the activity of enzymes and microorganisms, promoting the hydrolysis of proteins into amino acids and other umami substances, but at the same time, it can accelerate the deterioration and spoilage of food quality. Low temperature and humidity can delay the deterioration and spoilage of food quality, but at the same time, it slows down the hydrolysis of proteins into umami substances. Therefore, it is necessary to study the suitable storage conditions for fresh meat that are conducive to the production of umami substances and can extend the shelf life of food.

[0044] In order to preserve the freshness of meat as much as possible during storage and maximize its umami flavor, it is necessary to adjust the corresponding storage environment conditions according to the characteristics of different meat varieties. Considering that different meat varieties have different maturation times, the degree of protein hydrolysis into umami substances, and the retention time of umami substances, the storage conditions and optimal storage times of different varieties of fresh meat are different.

[0045] Currently, refrigerators are widely used for storing fresh meat. Refrigerators create a low-temperature environment through their refrigeration system, which slows down the spoilage of meat to some extent and provides a relatively stable space for preservation. Some refrigerators also have temperature and humidity control functions, allowing for regulation of the internal temperature and humidity within a certain range. However, while existing refrigerators offer some storage and environmental control capabilities, they cannot precisely tailor storage conditions to different types of fresh meat according to user needs. They struggle to simultaneously promote aging and extend the time the meat remains in its aged state, failing to adequately meet the diverse storage requirements of different meat varieties. Consequently, they are significantly inadequate in preserving the crucial quality of meat freshness and cannot fully satisfy people's expectations for maximizing meat flavor preservation.

[0046] Based on this, this application provides a fresh-keeping refrigerator and a fresh-keeping method. This application adjusts the fresh meat storage conditions in the refrigerator according to user-input fresh-keeping instructions, ensuring the fresh meat is stored under suitable conditions, thus facilitating both the maturation of the fresh meat and extending the maturation time. Furthermore, by rationally setting the storage structure, the application improves the fresh meat storage effect and optimizes the refrigerator's storage space layout.

[0047] In some embodiments, this application provides a food preservation refrigerator, such as... Figure 1 As shown, the refrigerator includes:

[0048] The system includes a display, a controller, and an independently temperature-controlled variable-temperature zone for storing fresh meat.

[0049] An electric field generating device for applying an electric field to the temperature-changing zone is provided within the temperature-changing zone.

[0050] The variable temperature zone is also equipped with temperature and humidity sensors;

[0051] The controller is configured to:

[0052] Obtain the user's input instructions for food preservation;

[0053] When the preservation instruction is for the fresh meat maturation stage, the fresh meat is preserved according to the first preservation condition;

[0054] When the preservation instruction is for the fresh meat preservation stage, the fresh meat shall be preserved in accordance with the second preservation conditions;

[0055] When the preservation instruction is in the normal storage stage, the fresh meat is preserved according to the third preservation condition; wherein, the storage temperature of the first preservation condition is greater than the storage temperature of the second preservation condition, which is greater than the storage temperature of the third preservation condition.

[0056] Based on the characteristics of different varieties of fresh meat, their storage time is divided into several stages. Taking pork as an example, it can be roughly divided into the initial maturation stage, the fresh storage stage, and the ordinary storage stage. The physiological changes of pork and its adaptability to temperature and humidity differ in each stage. Other varieties of fresh meat, such as beef, chicken, and fish, are also divided into corresponding stages according to their own characteristics.

[0057] Different types of fresh meat, such as beef, pork, chicken, and fish, have different optimal aging temperatures, humidity ranges, and tolerance for temperature and humidity fluctuations. For example, beef is typically best aged at relatively low and stable temperatures (around 0°C to 1°C) and higher humidity (around 85%-90%) to better break down proteins and improve texture and flavor. Chicken, on the other hand, is better suited to slightly higher temperatures (2°C to 4°C) and moderate humidity (75%-85%). Due to its different fat content and tissue structure, chicken is more susceptible to microbial influences, resulting in different temperature and humidity requirements. Therefore, it is necessary to plan the temperature and humidity control range for specific areas based on the characteristics of common fresh meat varieties.

[0058] For fresh meats suitable for micro-freezing, such as red meat like beef, it is generally recommended to control temperature fluctuations within ±0.5℃ during aging or long-term storage. For example, if the target temperature is set at -1℃, the actual temperature should ideally be maintained between -1.5℃ and -0.5℃. This minimal fluctuation range allows for more stable and uniform ice crystal formation in the meat, preventing repeated melting and recrystallization due to large temperature fluctuations, which can damage the meat's cell structure and affect its texture and quality. It also facilitates a more stable pace of hydrolysis and other biochemical reactions in the meat, ensuring a smooth aging process.

[0059] Under normal refrigerated storage conditions, the temperature fluctuation range for common fresh meats such as pork, chicken, and fish should ideally be controlled within ±1℃. For example, if the storage temperature for pork is set at 2℃, the actual temperature should be maintained between 1℃ and 3℃. This fluctuation range can inhibit the rapid growth and reproduction of microorganisms while adapting to the heat exchange conditions under refrigeration. It avoids the risk of spoilage due to excessively high temperatures, which would accelerate microbial growth, and the risk of frostbite due to excessively low temperatures, which would affect the color and taste of the meat. This ensures that the fresh meat maintains a good freshness and quality for a certain period of time.

[0060] Maturation Stage: For most fresh meat varieties, a relatively strict temperature and humidity environment is required in the early stages of maturation to inhibit microbial growth and changes in enzyme activity. For example, in the initial preservation stage of pork, the temperature can be set between 0℃ and 1℃, and the humidity maintained at 85%-90%, creating a good initial preservation environment and delaying quality changes as much as possible. For beef, the temperature can be set between -1℃ and 0℃, and the humidity maintained at 88%-92%, which is beneficial for the stability of its quality in the early stages of maturation. As time progresses, some physicochemical properties of fresh meat change, and the temperature and humidity should be adjusted accordingly. For example, in the middle stage of pork maturation, the temperature can be appropriately increased to 1℃ to 2℃, and the humidity adjusted to 80%-85% to adapt to changes in its internal substances while maintaining a good taste and freshness. For beef, the temperature can be adjusted to 0℃ to 1℃, and the humidity maintained at 85%-90%, ensuring a smooth maturation process and good quality. In the later stages of maturation, when the fresh meat is approaching its optimal consumption period, the focus of temperature and humidity regulation is to extend its edible time as much as possible while maintaining a certain level of quality. For example, in the later stages of pork production, the temperature can be slightly adjusted to 2°C to 3°C, and the humidity can be controlled at 75% to 80% to reduce the risk of spoilage caused by improper temperature and humidity; for beef, the temperature can be set to 1°C to 2°C and the humidity can be maintained at 80% to 85% to ensure its final edible value.

[0061] At different stages of fresh meat storage, the automatic adjustment function precisely regulates temperature and humidity according to the corresponding needs. For example, in the initial storage stage, some fresh meats may require lower temperatures and higher humidity to maintain better freshness. As storage time progresses into later stages, the temperature is appropriately increased and the humidity is decreased. This precise adjustment avoids maintaining a low-temperature, high-energy-consumption state throughout the entire storage process. Compared to the traditional setting of always maintaining a fixed low temperature and high humidity, it reduces unnecessary energy consumption for cooling and humidification, making the refrigerator's energy consumption distribution more reasonable, thereby reducing overall energy consumption to a certain extent.

[0062] Traditional refrigerators without automatic adjustment based on storage time often run their cooling and humidity control systems continuously according to a uniform standard, which can easily lead to over-cooling to ensure freshness or excessive dehumidification / humidification. Automatic adjustment, however, can accurately control temperature and humidity according to the stage of fresh meat's growth, preventing these over-operations. This allows the refrigerator's various control systems to operate more precisely to meet actual needs, thereby reducing extra energy consumption caused by ineffective operation and improving energy efficiency.

[0063] A humidity sensor is installed in the variable temperature zone to detect the air humidity in the zone in real time and transmit the humidity data to the controller.

[0064] When the humidity is lower than the set target humidity range, the controller activates humidification equipment, such as ultrasonic humidifiers or steam humidifiers, to release water vapor into the area and increase air humidity; when the humidity is higher than the target humidity range, it activates dehumidification equipment, such as condenser dehumidifiers or molecular sieve dehumidifiers, to remove excess moisture from the air and reduce humidity.

[0065] A humidity control module is used, which utilizes the principles of dehumidifiers and humidifiers to maintain stable humidity in each humidity zone by precisely controlling the evaporation or replenishment of water. It can also automatically fine-tune the humidity according to the storage volume of different types of fresh meat to ensure that the humidity is always at a level that is conducive to the preservation of that type of fresh meat.

[0066] The system is equipped with humidity sensors to monitor humidity changes in each area in real time. When the humidity deviates from the set optimal humidity range for a certain type of fresh meat, it will promptly provide feedback to the controller. The controller will then automatically activate corresponding adjustment measures, such as humidifying when the humidity is low and dehumidifying when the humidity is high, to ensure that the fresh meat is always in a suitable humidity environment and to preserve its freshness and quality to the greatest extent.

[0067] The ventilation system controls the airflow speed and direction within the designated area by adjusting the opening and closing of dampers and the speed of fans, resulting in a more even distribution of humidity and preventing localized areas from becoming too high or too low. Simultaneously, ventilation promotes the evaporation and diffusion of moisture from the surface of meat, helping to keep the meat dry and fresh.

[0068] The refrigerator is equipped with a special electric field generating module that can generate an alternating electric field of a specific frequency and intensity.

[0069] The controller adjusts the output parameters of the electric field generating module, such as voltage, current, and frequency, according to user instructions or preset programs, as well as factors such as the storage time and type of meat, thereby changing the electric field strength applied in the variable temperature zone.

[0070] To ensure user safety, multiple safety protection mechanisms are implemented during the electric field strength adjustment process. These include leakage current protection devices and electric field shielding devices to prevent electric field leakage from causing harm to the human body. Simultaneously, the electric field strength is monitored and fed back in real time; if any abnormality is detected, the application of the electric field is immediately stopped and an alarm is issued.

[0071] The refrigerator's controller has the function of intelligently identifying the type of fresh meat. For example, by setting up a barcode scanner inside the refrigerator, users can scan the barcode or QR code on the packaging of fresh meat when they put it in (if there is a relevant meat traceability label, etc.), or by using image recognition technology to identify the appearance characteristics of fresh meat to determine the type, and then the refrigerator will automatically match the corresponding optimal storage temperature mode.

[0072] The refrigerator's controller monitors the storage time and variety of fresh meat in real time. Based on preset temperature and humidity control strategies for different stages, it automatically determines which storage stage the meat is currently in. Once a new stage is determined, the system immediately sends instructions to the temperature and humidity control module, such as controlling the refrigeration system, humidifier, or dehumidifier, to precisely adjust the temperature and humidity of the corresponding area to the parameter range required for the new stage. During the temperature and humidity adjustment process, the actual values ​​after adjustment are fed back in real time by temperature and humidity sensors. If there is a deviation from the preset parameters, the controller promptly calibrates to ensure that the actual temperature and humidity match the optimal values ​​required for the fresh meat at that stage, guaranteeing the accuracy and effectiveness of temperature and humidity control, and thus better dynamically optimizing the storage environment according to the storage time of the fresh meat.

[0073] When fresh meat enters a new stage of storage, the refrigerator informs the user of the current storage stage of the fresh meat and the corresponding changes in temperature and humidity through the display screen, voice prompts, or push messages to the user's mobile app. This allows the user to understand the freshness status of the meat and makes it easier for them to plan their consumption time in advance.

[0074] When the temperature and humidity deviate from the optimal range for storing a certain type of fresh meat for an extended period, the system can push reminder messages to users via the app, informing them of potential risks to the quality of the fresh meat and prompting them to take timely action, such as adjusting the temperature and humidity or consuming the meat as soon as possible, thereby further improving the level of refined management of the storage of different varieties of fresh meat.

[0075] If users have special needs, such as wanting to further extend the storage time of a certain piece of fresh meat, the system can provide corresponding temperature and humidity adjustment suggestions based on the current storage stage and the type of fresh meat, informing users of the potential advantages and disadvantages of such adjustments, allowing users to decide whether to manually intervene, thus enhancing the interactivity between users and the refrigerator's temperature and humidity control function.

[0076] To cater to users' specific needs and preferences, the system allows users to make personalized adjustments to temperature and humidity within a reasonable range. For example, some users prefer firmer beef and may want slightly lower humidity. This kind of personalized setting can be easily made through the refrigerator's control panel. At the same time, the system will prompt users about the possible impact of such settings on preservation time, making it easier for users to weigh their options and make informed decisions.

[0077] In some embodiments, the controller is further configured to:

[0078] When the preservation instruction is for the fresh meat maturation stage, a timer is also started to record the preservation time;

[0079] When the preservation time exceeds the first threshold, the fresh meat is preserved according to the second preservation conditions; wherein the timer remains on.

[0080] When the preservation time exceeds the second threshold, the fresh meat is preserved according to the third preservation condition, and the timer is turned off; the first threshold is 72h, and the second threshold is 30d.

[0081] In some embodiments, the second preservation conditions include short-term storage and long-term storage, and when the preservation time exceeds a first threshold, it further includes:

[0082] When the preservation time exceeds the first threshold but is less than the third threshold, the fresh meat is preserved according to the short-term storage in the second preservation condition;

[0083] If the preservation time exceeds the third threshold but is less than the second threshold, the fresh meat shall be stored in accordance with the long-term storage in the second preservation conditions.

[0084] If the preservation time exceeds the second threshold, the fresh meat is preserved according to the third preservation conditions, and the timer is turned off; the third threshold is 15 days, the short-term storage temperature is -5℃ to 0℃, and the long-term storage temperature is -16℃ to -32℃.

[0085] The first preservation conditions include: a temperature of 0–4°C, a humidity of 50–80%, and an electric field strength of 50–1000 V / m. The second preservation conditions include short-term and long-term storage; wherein the short-term storage temperature is -5–0°C, the humidity is 30–80%, and the electric field strength is 500–1000 V / m; and the long-term storage temperature is -16°C–-32°C, the humidity is 30–80%, and the electric field strength is 500–1000 V / m. The third preservation conditions include: a temperature of -18–-20°C, a humidity of 20–80%, and an electric field strength of 1000–3000 V / m.

[0086] In some embodiments, the temperature adjustable range of the independently temperature-controlled variable temperature zone is -32℃ to 5℃.

[0087] Suitable temperature and humidity allow proteins and other substances inside fresh meat to undergo orderly decomposition and transformation during the aging process. For example, at the right temperature, proteases can function better, gradually hydrolyzing proteins into umami substances such as amino acids and peptides, making the meat more flavorful. At the same time, the meat becomes more tender, juicy, and elastic, improving any dryness or toughness that might have occurred before, thus enhancing the consumer's eating experience.

[0088] A time-recording unit is installed in the refrigerator's controller. When a user places fresh meat in a designated area of ​​the refrigerator, the system automatically begins recording the storage time. This time recording can be accurate to the minute or even the second, and corresponds to each individually stored portion of fresh meat. For example, it can be done by identifying the shelf location where the fresh meat is placed or by using specific identification tags to associate different batches of fresh meat with their storage times.

[0089] The controller combines fresh meat variety identification technology (such as the aforementioned barcode scanning or image recognition to determine the fresh meat variety) to time different varieties of fresh meat separately. Because different varieties of fresh meat have different optimal storage times and different requirements for temperature and humidity at different stages, they need to be recorded separately. For example, beef may have a relatively long storage time, while chicken may have a shorter storage time. The system needs to accurately track each variety based on its initial storage time.

[0090] In some embodiments, the drawer of the variable temperature zone includes an upper tray 1 and a lower drawer 2. The upper tray 1 is designed to be concave, with sloping side walls on all four sides, and evenly distributed holes on the sloping side. The upper tray 1 and the lower drawer 2 are combined to form a sealed cavity, and the sloping holes of the upper tray 1 are within the opening frame of the lower drawer 2. The air outlet of the variable temperature zone is located on the upper end of the upper tray on the rear wall of the zone.

[0091] In some embodiments, the electric field generating device includes an electric field generating end and an electric field releasing end, wherein the electric field generating end is installed on any side of the refrigerator top cover or compressor compartment, and the electric field releasing end is installed at any location on the side wall, bottom surface or top wall of the variable temperature zone. The voltage of the electric field generating end is 200V or 12V, and the frequency is 0.5 to 100KHz.

[0092] The display features a user-friendly interface, allowing users to easily set temperature and humidity parameters for different types of fresh meat, view real-time temperature and humidity conditions, and make personalized adjustments. It also provides a clear display that intuitively presents key information such as temperature and humidity status and storage time for each zone within the designated area, improving user convenience and control over storage conditions. The refrigerator display includes options for fresh meat (short aging stage, long aging stage, short-term fresh storage stage, long-term fresh storage stage, and normal storage stage). When a short aging stage is selected, "Short aging stage" is illuminated. After 72 hours of aging, the refrigerator enters the short-term fresh storage stage, and "Short-term fresh storage stage" is illuminated. When a long aging stage is selected, "Long aging stage" is illuminated. After 72 hours of aging, the refrigerator enters the long-term fresh storage stage, and "Long-term fresh storage stage" is illuminated. When the short-term fresh storage stage exceeds 15 days or the long-term fresh storage stage exceeds 30 days, the refrigerator enters the normal storage stage, and "Normal storage stage" is illuminated.

[0093] In some embodiments, this application also provides a preservation method, such as... Figure 2 As shown, the method includes:

[0094] Obtain the user's input instructions for food preservation;

[0095] When the preservation instruction is for the fresh meat maturation stage, the fresh meat is preserved according to the first preservation condition;

[0096] When the preservation instruction is for the fresh meat preservation stage, the fresh meat shall be preserved in accordance with the second preservation conditions;

[0097] When the preservation instruction is in the normal storage stage, the fresh meat is preserved according to the third preservation condition; wherein, the storage temperature of the first preservation condition is greater than the storage temperature of the second preservation condition, which is greater than the storage temperature of the third preservation condition.

[0098] The preservation method provided in this application is applied to the refrigerator in the above embodiments. This preservation method is configured in the controller of the refrigerator. The intelligent algorithm in the controller will automatically adjust the temperature control strategy according to different usage scenarios and storage needs, such as different types of meat and different storage times. At the same time, it can also predict temperature changes in advance and make pre-adjustments based on historical temperature data and ambient temperature change trends to reduce temperature fluctuations.

[0099] Different consumers have different requirements regarding the degree of aging and consumption time of fresh meat. Some consumers prefer meat with a higher degree of aging and richer flavor, and hope to extend the aging time to achieve the desired effect; while other consumers may need to preserve fresh meat for a short period of time and consume it as soon as possible. By setting up suitable temperature-controlled zones, consumers can choose the corresponding storage method according to their needs, flexibly control the aging process and preservation time of fresh meat, and better meet their personalized dietary and lifestyle habits.

[0100] The preservation method provided in this application dynamically adjusts the temperature according to user instructions or storage time, enabling meat products to be in the most suitable aging temperature environment at different stages. For example, in the early stages of storage, setting the temperature at a slightly lower level can inhibit the growth of microorganisms and excessive enzyme reactions. As the storage time increases, appropriately raising the temperature helps to activate proteases and other related enzymes in the meat, promoting the orderly hydrolysis of proteins into umami substances such as amino acids and peptides, making the meat flavor richer, the texture more tender and juicy, and improving the overall quality of the meat.

[0101] Applying an appropriate electric field strength can affect the movement of charged particles in meat and the rate of some biochemical reactions. For example, under the influence of a certain electric field, the diffusion and exchange of substances inside the meat may be moderately accelerated, resulting in a more even distribution of umami substances, improved aging effect, and more consistent quality of the meat from the inside out.

[0102] By precisely regulating temperature and humidity, an environment unfavorable to microbial growth, enzymatic reactions, and accelerated chemical reactions can be created. Lower temperatures directly reduce microbial activity and slow their reproduction, while appropriate humidity reduces the risk of spoilage caused by moisture issues. The combination of these two factors effectively delays the spoilage process of meat, thereby extending shelf life and reducing food waste.

[0103] Appropriate electric field strength can, to some extent, alter the permeability of meat cells, inhibit certain oxidative reactions and microbial metabolic processes that lead to meat spoilage, further enhance the preservation effect, and keep the meat in a good edible state for a longer period of time.

[0104] This application allows users to adjust various parameters of the variable-temperature zone based on their instructions, meeting the personalized needs of different users for meat storage. For example, some users prefer aged meat with a firmer texture and richer flavor, and can adjust the temperature, humidity, and electric field intensity according to their personalized settings via instructions to extend the aging time and achieve the desired quality. Other users who want to preserve fresh meat for a short period and consume it as soon as possible can also quickly adjust the parameters to achieve rapid preservation. Whether for daily family use, stocking up on ingredients for parties, or the specific storage requirements of the catering industry for different dishes, the variable-temperature zone parameters can be flexibly adjusted to meet these needs, greatly improving the refrigerator's adaptability to different usage scenarios.

[0105] As meat is stored for an extended period, its physicochemical properties change, and the requirements for the storage environment also change accordingly. Automatically adjusting temperature, humidity, and electric field intensity based on storage time can meet the needs of meat at different stages, ensuring it remains in an optimal preservation and maturation environment. For example, for a piece of beef planned for long-term storage, the initial focus is on inhibiting microbial growth and maintaining meat quality stability, while the later stage emphasizes promoting maturation. The system automatically adjusts parameters according to storage time, ensuring the scientific and rational nature of the entire storage process.

[0106] Example 1

[0107] like Figure 3 As shown in the figure, pork tenderloin was aged at 0℃~4℃ and humidity of 50%~80%, and an electric field with an intensity of 50~3000V / m was applied to the aging space for 72 hours. The results are shown in the figure below. The protein content of the group without electric field was higher than that of the group with electric field, indicating that the electric field is conducive to the hydrolysis of pork tenderloin protein to produce small molecule flavor substances such as umami amino acids.

[0108] Example 2

[0109] like Figure 4 As shown in the figure, aged pork tenderloin stored at -18℃ for 90 days exhibits minimal changes in umami amino acid content during the first 30 days. However, from 30 to 90 days of storage, the umami amino acid content drops significantly, severely impacting the taste and nutritional value of the fresh meat. Therefore, fresh meat can be stored in a freezer for up to 30 days.

[0110] Example 3

[0111] In the temperature-controlled storage area, the air vents of the temperature-controlled area pass through the upper tray of the temperature-controlled area. After circulating within the concave upper tray, a small amount of recirculated air enters the lower drawer through the sloping openings on the side walls of the upper tray. This maintains the humidity in the lower drawer between 50% and 80%, which is beneficial for the aging and storage of the fresh meat.

[0112] This application studies the preservation effect of different varieties of fresh meat under different temperature and humidity combinations, and constructs a mathematical model for the coordinated regulation of temperature and humidity. For example, it clarifies the impact of a certain percentage change in humidity on the retention time of umami substances in pork at a specific temperature. Based on this model, the refrigerator controller can intelligently adjust the humidity in sync with the temperature adjustment to ensure that the temperature and humidity are always in the optimal coordinated state for a specific variety of fresh meat.

[0113] As can be seen from the above embodiments, this application provides a refrigerator and a method for preserving fresh meat. The refrigerator includes a display, a controller, and a temperature-controlled variable-temperature zone. The variable-temperature zone is used to store fresh meat. An electric field generating device for applying an electric field to the variable-temperature zone is provided within the variable-temperature zone. A temperature and humidity sensor is also provided within the variable-temperature zone. The controller is configured to: acquire a fresh meat preservation command input by a user; when the fresh meat preservation command is for the meat maturation stage, preserve the fresh meat according to a first preservation condition; when the fresh meat preservation command is for the meat fresh storage stage, preserve the fresh meat according to a second preservation condition; and when the fresh meat preservation command is for the ordinary storage stage, preserve the fresh meat according to a third preservation condition. This application adjusts the fresh meat storage conditions in the refrigerator according to the fresh meat preservation command input by the user, so that the fresh meat is stored under suitable conditions, which is conducive to the maturation of the fresh meat and can prolong the maturation time. On the other hand, by reasonably setting the storage structure, the fresh meat storage effect is improved and the refrigerator storage space layout is optimized.

Claims

1. A fresh-keeping refrigerator, characterized in that, The refrigerator comprises: a display, a controller, and a temperature-variable special area with independent temperature control; the temperature-variable special area is used for storing fresh meat; an electric field generating device is arranged in the temperature-variable special area and used for applying an electric field to the temperature-variable special area; a temperature and humidity sensor is further arranged in the temperature-variable special area; the controller is configured to: obtain a fresh-keeping instruction input by a user; when the fresh-keeping instruction is a fresh meat ripening stage, fresh meat is fresh-kept according to a first fresh-keeping condition; when the fresh-keeping instruction is a fresh meat fresh storage stage, the fresh meat is fresh-kept according to a second fresh-keeping condition; when the fresh-keeping instruction is a common storage stage, the fresh meat is fresh-kept according to a third fresh-keeping condition; wherein the storage temperature of the first fresh-keeping condition > the storage temperature of the second fresh-keeping condition > the storage temperature of the third fresh-keeping condition; the first fresh-keeping condition comprises: a temperature of 0-4 ℃, a humidity of 50-80%, and an electric field intensity of 50-2000 V / m; the second fresh-keeping condition comprises short-term storage and long-term storage; wherein the temperature of the short-term storage is -5-0 ℃, the humidity is 30-80%, and the electric field intensity is 500-2000 V / m; the temperature of the long-term storage is -16 ℃ to -32 ℃, the humidity is 30-80%, and the electric field intensity is 500-2000 V / m; the third fresh-keeping condition comprises: a temperature of -18 to -20 ℃, a humidity of 20-80%, and an electric field intensity of 500-3000 V / m.

2. The fresh-keeping refrigerator according to claim 1, characterized by the controller is further configured to: when the fresh-keeping instruction is the fresh meat ripening stage, a timer is further started to record a fresh-keeping time; when the fresh-keeping time exceeds a first threshold, the fresh meat is fresh-kept according to the second fresh-keeping condition; wherein the timer remains in an open state; when the fresh-keeping time exceeds a second threshold, the fresh meat is fresh-kept according to the third fresh-keeping condition, and the timer is closed; the first threshold is 72 h, and the second threshold is 30 d.

3. The fresh-keeping refrigerator according to claim 2, characterized by the second fresh-keeping condition comprises short-term storage and long-term storage, and further comprises the following when the fresh-keeping time exceeds the first threshold: when the fresh-keeping time exceeds the first threshold and is less than a third threshold, the fresh meat is fresh-kept according to the short-term storage in the second fresh-keeping condition; when the fresh-keeping time exceeds the third threshold and is less than the second threshold, the fresh meat is stored according to the long-term storage in the second fresh-keeping condition; when the fresh-keeping time exceeds the second threshold, the fresh meat is fresh-kept according to the third fresh-keeping condition, and the timer is closed; the third threshold is 15 d, the short-term storage temperature is -5 ℃ to 0 ℃, and the long-term storage temperature is -16 ℃ to -32 ℃.

4. The fresh-keeping refrigerator according to claim 1, characterized in that, The temperature of the temperature-variable special area with independent temperature control can be adjusted in a range of -32 ℃ to 5 ℃.

5. The fresh-keeping refrigerator according to claim 1, characterized in that, The drawer of the temperature-variable special area comprises an upper tray and a lower drawer bin, wherein the upper tray is designed as a concave type, the four side walls of the concave type are inclined surfaces, and the inclined surfaces are uniformly distributed with cavities; the upper tray and the lower drawer bin are combined into a sealed cavity, and the cavity of the upper tray is in the lower drawer bin; and an air outlet of the temperature-variable special area is arranged on the upper end of the upper tray on the rear wall of the special area.

6. The fresh-keeping refrigerator according to claim 1, characterized in that, The electric field generating device comprises an electric field generating end and an electric field releasing end, wherein the electric field generating end is installed on any side of the refrigerator top cover or the compressor compartment, the electric field releasing end is installed on any of the side wall, bottom surface or top wall of the variable temperature area, the voltage of the electric field generating end is 200V or 12V, and the frequency is 0.5-100KHz.

7. A method for preserving, characterized by, The fresh-keeping method is applied to the refrigerator of any one of claims 1-6, and the method comprises: obtaining a fresh-keeping instruction input by a user; when the fresh-keeping instruction is a fresh meat ripening stage, fresh-keeping the fresh meat according to a first fresh-keeping condition; when the fresh-keeping instruction is a fresh meat fresh storage stage, fresh-keeping the fresh meat according to a second fresh-keeping condition; when the fresh-keeping instruction is a general storage stage, fresh-keeping the fresh meat according to a third fresh-keeping condition; wherein the storage temperature of the first fresh-keeping condition > the storage temperature of the second fresh-keeping condition > the storage temperature of the third fresh-keeping condition.

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