Freezing method and apparatus for fresh food ingredients

Abstract

An object of the present invention is to reduce the amount of drip that flows out during thawing of frozen food materials and to perform a freezing process of fresh food materials that maintains texture, deliciousness, and nutrition. 【Solution means】 When freezing fresh food materials, an apparatus having a freezing function, a function of applying appropriate mechanical impact vibration, and a function of detecting the temperature of the food materials to be frozen is used. In the process of passing through the maximum ice crystal formation temperature zone during cooling and freezing, by continuously applying impact vibration in a predetermined mechanical gravity direction at a predetermined cycle, the growth of needle-shaped ice crystals is finely crushed each time, and cell destruction by the needle-shaped ice crystals is suppressed.

Description

Technical Field

[0001] The present invention relates to an apparatus having a freezing function and a function of adding appropriate mechanical impact vibration when freezing fresh food materials. When freezing an object to be cooled, i.e., fresh food materials loaded on the apparatus, during the process of passing through the maximum ice crystal formation temperature zone where the water in the cells of the fresh food materials begins to freeze and ice crystals grow, by continuously applying impact vibration in a predetermined mechanical gravity direction, the growth of needle-shaped ice crystals that destroy the cells of the fresh food materials is finely crushed each time, and by suppressing the cell destruction of the fresh food materials by the needle-shaped ice crystals, the amount of drip flowing out during thawing of the frozen food materials is reduced, and it relates to a method and apparatus for freezing fresh food materials that maintain texture, taste, and nutrition.

Background Art

[0002] Conventionally, when freezing fresh food materials such as beef, as a basic method for suppressing the amount of drip generated by cell destruction due to freezing of the fresh food materials, there is a rapid freezing method in which the cooling temperature during the freezing process is lowered as much as possible and the cooling air speed to the object to be cooled, i.e., the fresh food materials, is increased to increase the freezing speed. Further, as auxiliary techniques for improving the freezing and thawing quality, those using supercooling, those using electromagnetic fields, microwaves, or ultrasonic waves have been reported.

[0003] The water in fresh food materials begins to freeze from around -1°C and is almost completely frozen at around -5°C. During this period, water generates needle-shaped ice crystals and grows large. This temperature range of -1°C to -5°C is regarded as a special maximum ice crystal formation temperature zone. If the passing time through this temperature zone is long and it passes slowly, the ice crystals become larger, and the cell tissue of the fresh food materials is greatly deformed and damaged. Therefore, in order to minimize such damage, it is necessary to pass through it in a short time. As a certification standard for frozen food manufacturing factories, it is stated that 'when the product is frozen, the central temperature of the product passes through the maximum ice crystal formation temperature zone within approximately 30 minutes'. This freezing method is called the rapid freezing method. On the other hand, the freezing method that takes time is called the slow freezing method.

[0004] It is a well-known fact that by the above rapid freezing method, the maximum ice crystal formation temperature zone can be passed through in about 30 minutes, the growth of ice crystals can be reduced, and the destruction of the cell tissue of fresh food can be suppressed. Therefore, in the frozen food industry in various fields, it is highly regarded for maintaining the quality of frozen ingredients, and it is also installed as various rapid freezing functions in household freezers and is regarded as one of the selling points. However, in order to temporarily increase the freezing capacity, equipment with more freezing performance than necessary and continuous operation are required, which poses problems in terms of energy conservation, and there are also problems with variations in freezing quality due to differences in the thickness of the food to be frozen.

[0005] Patent Document 1 introduces a refrigerator that is provided with a rapid freezing container having a metal plate on the bottom surface so as to enable rapid freezing for home freezing, and a cold air duct that discharges cold air for directly cooling the food in the rapid freezing container above the upper surface opening of the rapid freezing container, and further divides the freezing chamber into three stages with three rapid freezing containers that limit the storage depth to be shallow.

[0006] That is, since the moisture in fresh food forms ice crystals and grows greatly to destroy the cell tissue in the maximum ice crystal formation temperature zone of -1 to -5°C, in order to pass through this temperature zone as quickly as possible, cold air is directly blown from above the food, and by placing a metal plate with good heat conductivity on the bottom surface, cooling from below the food can also be carried out smoothly. Furthermore, the container is divided into three shallow sections so that thick items cannot be stored, and the food is required to be thinly divided, and it is designed so that the central part of the food cools quickly.

[0007] As a freezing treatment method for further improving the rapid freezing method and enhancing the quality of frozen food, there is one that utilizes supercooling. Patent Document 2 introduces a method for freezing and storing food in which a preliminary cooling step of cooling the central temperature of the food to be stored to 0 to 3°C is provided, then it is cooled and stored in a supercooled state at -10°C, and then the supercooling is released by temperature fluctuation or mechanical shock to instantaneously start the freezing of the entire food, and then storage is performed at a lower temperature.

[0008] Similarly, Patent Document 3 also introduces a refrigerator that uses a control method to cool food into a supercooled state where the food does not freeze even at a temperature below the freezing point, and after the supercooled state is released, the volume or speed of the incoming cold air is increased to quickly freeze the food.

[0009] With this freezing method that utilizes supercooling, the entire fresh food ingredient is in a supercooled state, and when the supercooling is released by some kind of stimulus, tiny ice nuclei instantly form within the cells of the fresh food ingredient and begin to freeze, making the ice crystals smaller and minimizing damage to the cellular tissue of the fresh food ingredient.

[0010] Furthermore, Patent Document 4 introduces a refrigerator that is equipped with a cooling device that cools the object to be cooled, a storage chamber that stores the object to be cooled, a microwave generator that applies microwaves, and a control device that controls them, and the storage chamber is provided with a food plate that is transparent to microwaves and has an opening that allows cold air to flow in.By using microwaves and the food plate to freeze the object while suppressing temperature unevenness that occurs in the object, the ice crystals throughout the food can be made small and uniform, thereby achieving high-quality freezing that suppresses damage to the food's cellular tissue.

[0011] Patent Document 5 also introduces an ultra-rapid freezing method and an apparatus thereof that maintains the freshness of ingredients and foods and enables long-term storage, comprising the steps of applying a unidirectional magnetic field to the object to be frozen and cooling the surrounding temperature of the object to -30 to -100°C to rapidly freeze the object, and cooling the object to be frozen with cold air of 1 to 5 m / sec and superimposing audible frequency sound waves on the cold air, in which the strength of the unidirectional magnetic field fluctuates within a predetermined range in the positive and negative directions relative to an arbitrary fixed value in the range of 1 to 20,000 Gs and at a frequency of 50 or 60 Hz. The merit of the method is that the application of a magnetic field during freezing controls the molecular motion of water that causes stable supercooling, thereby breaking down the ice into small pieces.

[0012] Also, although different from the freezing treatment, Patent Document 6 discloses a method for thawing frozen products in a container by applying an alternating voltage of 10 V or more and 5 kV or less to the frozen products so that a current of 1 μA or more and 1000 mA or less flows through the frozen products. In this method, while applying the alternating voltage to the frozen products, the temperature inside the container is controlled to reach a semi-thawed state in which the frozen products are thawed at a negative temperature between 0°C and -10°C. The method includes a semi-thawing step of thawing the frozen products and a storage step of stopping the application of the alternating voltage to the frozen products and maintaining the semi-thawed state to store the frozen products.

[0013] Although this document describes a thawing method rather than a freezing method, it controls the temperature to reach a semi-thawed state in which the frozen products are thawed at a negative temperature between 0°C and -10°C. In a temperature range approximating this maximum ice crystal formation temperature range, freezing and thawing occur microscopically even during the thawing process. If an alternating voltage is applied and a minute current is passed to suppress the crystal growth at that time, it is highly relevant as a freezing method and has a high possibility as a method for improving frozen quality, and can be said to be an easily conceivable method.

[0014] Also, although it is also a thawing method like the prior document, Patent Document 7 discloses a thawing method without cell membrane destruction during thawing. In this method, the object to be thawed is placed on an external vibration applying device composed of an electromagnetic vibration generating unit and a metal thawing plate, and the metal electrode of a Joule heating device composed of a power supply for energization and a metal electrode is placed on the upper part of the frozen fish meat block. A thawing method for frozen fish and shellfish is introduced, in which minute vibrations with an amplitude of 1 mm or less and a frequency of 10 Hz to 10 kHz are applied to the frozen fish meat block from the outside, and at the same time, the frozen fish meat block is energized to perform Joule heating.

[0015] It can be easily thought that this thawing method can also be applied to the freezing method. However, when passing through the maximum ice crystal formation temperature zone during thawing, the aim is to equalize the temperature of the thawed product by applying slight vibrations of the electromagnetic vibration generating part that causes lateral vibrations. However, it remains a question whether it is possible to suppress the growth of ice crystals during the freezing process by this method. Basically, there is a significant difference in the hardness of the target food between thawing and freezing, and it is speculated that even if this treatment condition is effective for thawing, it will have no effect during freezing.

[0016] Also, Patent Document 8 introduces a method for freezing and thawing food using ultrasonic waves, in which food to be stored for a long time by freezing is placed in a predetermined state where it can vibrate by ultrasonic waves, and the food is rapidly frozen at a predetermined low temperature while ultrasonic waves are applied to the food, and when thawing the frozen food stored by freezing, thawing is rapidly performed while ultrasonic waves are applied.

[0017] According to this document, the reason for applying ultrasonic waves during freezing is to reduce the temperature difference between the surface and the inside, reduce the separation of moisture from the tissue, achieve uniform freezing, suppress crystal growth during freezing, and freeze with small crystals to eliminate the destruction of cell tissue.

[0018] Also, Patent Document 9 introduces a cooling storage refrigerator equipped with a cooler and a freezing chamber that cools and freezes an object to be cooled by cold air from this cooler. On the back side of the container on which the object to be cooled is placed in this freezing chamber, an ultrasonic vibrator that applies ultrasonic vibrations to the object to be cooled during the cooling of the object to be cooled is attached.

[0019] The role of this ultrasonic vibrator is to apply ultrasonic vibration to the object to be cooled by the ultrasonic vibrator, and the thermal energy imparted to the object to be cooled by this ultrasonic vibrator is made smaller than the thermal energy taken away from the object to be cooled by the cold air, so that the temperature can be equalized by freezing the object to be cooled, and it is assumed that the ice crystals can be made smaller and the drip can be reduced. Note that it is considered sufficient to operate the ultrasonic vibrator during the generation and growth of ice crystals during freezing, and it is also introduced that it is up to the end of passing through the maximum ice crystal growth temperature zone at the end of freezing.

[0020] Also, Patent Document 10 discloses a method for freezing organic tissues. The pressure of the atmosphere in contact with the organic tissue is reduced from about -0.03 kg / cm2 to about -0.07 kg / cm2 per minute to a minimum pressure of about 0.9 kg / cm2 to about 0.6 kg / cm2 below atmospheric pressure, releasing about half of the gaseous substances that can dissolve in the tissue with little water evaporation from the tissue. On the other hand, the tissue is cooled to a temperature of about -10°C to about 0°C, and the organic tissue freezing treatment method of stirring the tissue at a rate of about 25 cycles to about 100 cycles per minute is introduced. Note that the amplitude at that time is a gentle vibration, and the displacement amplitude is obtained by lateral vibration of about 2.5 cm to 25 cm.

[0021] It is introduced that this lateral vibration first forms a mass of small crystals prior to large crystals inside the cells, and in order to promote this, the cooling and depressurization processes are accompanied by stirring and vibration of the cell tissue.

[0022] Also, Patent Document 11 discloses a method for manufacturing an object to be cooled that can automatically manufacture ice confections such as ice cream and sherbet with good texture and excellent design by automatically stirring and shaping the raw materials in a freezer. It includes a cooling dish having a hemispherical recess on the bottom surface for storing a liquid or liquid material of the object to be cooled, a freezer for cooling the cooling dish, and a vibration applying device for applying vibration to the cooling dish.

[0023] As this vibration application, rocking agitation is introduced. By repeating this operation, the ice confectionery raw material is cooled while being sufficiently agitated, and freezing progresses. Freezing starts from the periphery of the ice confectionery raw material and creeps up to the upper surface of the cooling plate or the inner surface of the cooling plate. These ice crystals are peeled off by vibration and are well mixed with the unfrozen part of the ice confectionery raw material, suppressing the growth and unevenness of the ice crystals and enabling the production of an ice confectionery with a smoother texture. Also, in order to promote the peeling of the ice formed on the inner surface of the cooling plate, it is stated that the cooling plate may be moved so as to be freely dropped to give an impact vibration to the cooling plate when the cooling plate is lifted and returned to the horizontal position.

Prior Art Documents

Patent Documents

[0024]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Patent Document 10

Patent Document 11

Summary of the Invention

Problems to be Solved by the Invention

[0025] However, in the refrigerator disclosed in Patent Document 1, the food surface directly contacted by the cold air or the food surface in contact with the metal plate freezes rapidly, and the growth of ice crystals due to rapid freezing is suppressed. However, as the freezing rate decreases from the food surface to the center, the passage of the maximum ice crystal formation temperature zone through the center of the food is slower than that of the surface part, and it is considered that large ice crystals are formed. For this reason, there is a variation in the size of ice crystals generated inside and on the surface of the food, and there is concern about the deterioration of the frozen quality in the center of the food. In particular, it has a significant impact when storing thick ingredients or stacking them. In Patent Document 1, by partitioning the shelves in the freezer into three levels, it is dealt with by processing and storing the ingredients as thin as possible, but this is not a fundamental solution, and problems such as time-consuming and storage space problems will occur.

[0026] Also, although the freezing treatment method that freezes the center of the frozen food all at once by utilizing supercooling in Patent Document 2 and Patent Document 3, it is impossible to suppress the instability of supercooling and the growth of ice after supercooling is released. Even if combined with rapid freezing, the freezing in the maximum ice crystal formation temperature zone of the food center is slow. Therefore, there is a limit to suppressing the drip amount after thawing, resulting in quality variations and it has not been a sufficient solution to the problems.

[0027] Also, the application of microwaves in Patent Document 4 uses microwaves that control the molecular movement of water, and it is very difficult to finely adjust and control the temperature of water inside fresh food materials. There are major problems in that suppressing ice crystals in the maximum ice crystal formation temperature zone becomes unstable.

[0028] In addition, the control of water molecules by a magnetic field in Patent Document 5 and the control of water molecules by an electric field in Patent Document 6 have poor reproducibility of significant differences depending on their presence or absence and have unclear points. As the final device with an applied magnetic field, it has the effect of ultra-rapidly freezing food materials with a large air volume at extremely low temperatures. Regarding the effect of products equipped with an electric field, the data mainly disclose the comparison of the drip amount at the micro-freezing and thawing temperatures. Ultimately, the effect of the electromagnetic field lacks scientific basis, and currently, there is no evidence that simply the presence or absence of the electromagnetic field can improve the quality of frozen food.

[0029] In addition, the thawing method in Patent Document 7 is a thawing method that applies external micro-vibrations to frozen fish meat blocks and simultaneously energizes the frozen fish meat blocks for Joule heating. An electromagnetic vibration is used as the external vibration applying device, and the applied vibration frequency is a micro-vibration of transverse vibration with a frequency of 10 Hz to 10 kHz and an amplitude of 1 mm or less. Therefore, for hard-frozen frozen products, the vibration can be transmitted to the whole food and is effective during thawing. However, for raw materials such as fresh food ingredients with a soft texture, it can be said that it is impossible to transmit the vibration to the whole food ingredient with a transverse vibration of 1 mm or less. Therefore, it is not suitable as a freezing method.

[0030] In addition, even in the freezing treatment method that suppresses the growth of ice crystals by using ultrasonic waves in Patent Documents 8 and 9, if the ultrasonic wave frequency exceeds the audible range, the lowest is about 20 kHz, and the amplitude is of the order of several microns. Therefore, even if the design is such that the hard container resonates, in fresh food ingredients that contain a lot of water in the cell nucleus and are relatively soft, the vibration is absorbed at the surface of the fresh food ingredient, and the vibration strong enough to crush the ice crystals growing during freezing cannot be transmitted to the whole object to be cooled. Therefore, even if a logic such as temperature control by heat generation by ultrasonic waves or making the water clusters finer in part is constructed, the effect of stably suppressing the drip amount during the freezing and thawing of actual fresh food ingredients cannot be obtained.

[0031] In addition, Patent Document 10 discloses a method of freezing organic tissues by applying gentle lateral vibrations while decompressing the inside of a freezing container. It is stated that the tissues are agitated at a rate of about 25 to about 100 cycles per minute, and the displacement amplitude is obtained by lateral vibrations of about 2.5 cm to 25 cm. However, it is a smooth lateral vibration that does not produce an impact sound, and if it is a liquid object, it can be uniformly agitated, but it cannot surely and stably exert sufficient force to crush the crystals of water and ice inside fresh food ingredients.

[0032] In addition, Patent Document 11 also describes an apparatus that places raw materials such as ice cream and sherbet-like frozen confections in a predetermined cooling dish, applies rocking vibrations for agitation and shaping. In the description, in order to promote the peeling of the ice formed on the inner surface of the cooling dish, an operation of freely dropping the cooling dish so as to apply impact vibrations to the cooling dish when lifting and returning the cooling dish horizontally is also described. However, it is only a limited movement for the purpose of peeling from the cooling dish, and it does not solve the problem even if fresh food ingredients are frozen with this vibration applying device.

[0033] The present invention has been made to solve the above problems. When freezing fresh food ingredients, in the process of passing through the maximum ice crystal formation temperature zone where ice crystals grow, by applying mechanical impact vibrations that do not damage the cells of the fresh food ingredients and appropriately control the growth of ice crystals, cell destruction is suppressed, the amount of drip that flows out when thawing frozen food ingredients is reduced, and an object is to provide a method and an apparatus for freezing fresh food ingredients that maintain texture, taste, and nutrition.

Means for Solving the Problems

[0034] Therefore, the present invention provides a means to stably, surely, and more simply solve the problem of suppressing cell destruction caused by ice crystal formation during freezing of fresh food materials, which could not be solved by rapid freezing, supercooling, electromagnetic fields, microwaves, ultrasonic waves, stirring, or horizontal vibration. During the process in which the water inside the cells of the fresh food material begins to freeze and the ice crystals grow and pass through the maximum ice crystal formation temperature zone, by continuously applying impact vibration in a predetermined mechanical gravitational direction at a predetermined cycle, the growth of needle-shaped ice crystals that damage the cells of the fresh food material is finely crushed each time, thereby suppressing cell destruction by the needle-shaped ice crystals. As a result, the amount of drip that flows out during thawing of the frozen food material is reduced, and the texture, taste, and nutrition are maintained.

[0035] That is, in order to solve the above problems, a freezing treatment method for fresh food materials according to a first aspect of the present invention cools a cooled object that is a fresh food material to pass through the maximum ice crystal formation temperature zone, and when storing the cooled object frozen at a temperature below the maximum ice crystal formation temperature zone, only during the process in which the cooled object is maintained at a temperature including the maximum ice crystal formation temperature zone, the cooled object is lifted to a predetermined height and then dropped with the force of gravitational acceleration, and a mechanical impact vibration is continuously applied at a predetermined cycle to perform a cooling and freezing treatment method for fresh food materials.

[0036] According to this freezing treatment method for fresh food materials, when the cooled object of the fresh food material passes through the maximum ice crystal formation temperature zone of -1°C to -5°C during cooling and freezing, the cooled object is lifted to a predetermined height and then dropped with gravitational acceleration, and the mechanical impact vibration is applied. The entire cooled object of the fresh food material receives impact vibration uniformly with its own weight at a predetermined gravitational acceleration, and the ice crystals growing inside the cells of the cooled object of the fresh food material are finely crushed each time by the impact vibration, so that damage to the cell wall can be suppressed, and it is possible to reduce the outflow of drip after thawing.

[0037] Moreover, the freezing method for fresh food according to the second aspect of the present invention relates to a freezing method for fresh food in which the object to be cooled, which is fresh food, is lifted to a predetermined height and the mechanical impact vibration caused by the force of gravitational acceleration is continuously applied at a cycle of 60 times or more and 600 times or less per minute to perform cooling and freezing treatment.

[0038] According to this freezing method for fresh food, when the object to be cooled of fresh food passes through the maximum ice crystal formation temperature range of -1°C to -5°C during cooling and freezing, if the mechanical impact vibration that lifts the object to be cooled to a predetermined height and drops it with the force of gravitational acceleration is less than 60 times per minute, the ice crystals grow larger than the cell size, and the inhibitory effect is lost. Also, if the mechanical impact vibration is more than 600 times per minute, due to the elasticity of the object to be cooled of fresh food, which is relatively soft, the impact vibration is absorbed by the surface, so the effect is halved, or the elasticity is lost and the surface is damaged by plastic deformation.

[0039] Moreover, the freezing method for fresh food according to the third aspect of the present invention relates to a freezing method for fresh food in which the object to be cooled, which is fresh food, is lifted to a predetermined height and the mechanical impact vibration caused by the force of gravitational acceleration is applied to perform cooling and freezing treatment, and the predetermined height is set to 1 mm or more and 10 mm or less.

[0040] According to this freezing method, when the height of lifting the object to be cooled is 1 mm or more and then dropped, the impact vibration due to gravitational acceleration is evenly transmitted to the whole of the object to be cooled, and the ice crystals growing inside the cells of the object to be cooled of fresh food are finely crushed by the impact vibration, so that damage to the cell membrane can be suppressed and the outflow of drip after thawing can be reduced. Also, by setting the lifting height to 10 mm or less, damage to the outer surface layer of the object to be cooled, which is relatively soft in fresh food, can be prevented. That is, by adjusting the lifting height to 1 mm or more and 10 mm or less according to the vulnerability of the object to be cooled, it is possible to adjust the appropriate impact vibration intensity according to the food.

[0041] Further, the freezing method for fresh food according to the fourth aspect of the present invention cools the object to be cooled, which is fresh food, to pass through the maximum ice crystal formation temperature zone, and when storing the object to be cooled frozen at a temperature below the maximum ice crystal formation temperature zone, only during the process in which the object to be cooled is maintained at a temperature including the maximum ice crystal formation temperature zone, while playing a rhythm or melody of a predetermined pleasant volume, the object to be cooled is lifted to a predetermined height and dropped with gravitational acceleration, and a mechanical impact vibration is continuously applied at a cycle of 60 times or more and 600 times or less per minute to perform a freezing process for fresh food.

[0042] According to this freezing method for fresh food, when passing through the maximum ice crystal formation temperature zone of -1°C to -5°C, even if the mechanical impact vibration sound of lifting the object to be cooled to a predetermined height and dropping it with gravitational acceleration can be heard during the freezing process, the feeling is directed towards the predetermined pleasant volume and rhythm or melody, and the impact sound is cancelled out. During this period, a sense of security and acceptance that it is in the process of cooking can be obtained, and the annoyance with respect to the impact vibration sound is reduced. Usually, the time for passing through the maximum ice crystal formation temperature zone is 30 minutes to 60 minutes, and the playing time is completed in a short time even in a living environment.

[0043] Further, the freezing device for the object to be cooled of fresh food according to the fifth aspect of the present invention includes a detachable loading container on which the object to be cooled of fresh food is loaded, a freezer having a freezing function in which the loading container is stored and cooled by cold air from a cooler, and a function of lifting the detachable loading container on which the object to be cooled is loaded to a predetermined height and dropping it with the force of gravitational acceleration to apply a mechanical impact vibration in the gravitational direction. Mechanical shock and vibration adderand a product temperature detection means having a function of detecting the approximate temperature of the object to be cooled from the surface temperature of the object to be cooled, and during cooling by the refrigeration function, based on a signal from the product temperature detection means, water inside the cells of the object to be cooled of the fresh food starts to freeze, and it is detected from the approximate temperature that the object to be cooled passes through the maximum ice crystal formation temperature zone where ice crystals further grow, and only during that period, a control device is provided which drives a mechanical impact vibration adder that continuously applies a predetermined mechanical impact vibration in the direction of gravity at a cycle of 60 times or more and 600 times or less per minute. The present invention relates to a freezing treatment apparatus for fresh food.

[0044] Thereby, by applying a mechanical impact vibration in the direction of gravity to a detachable loading container on which the object to be cooled of the fresh food is placed, it is transmitted to the object to be cooled, and by a product temperature detection means that detects the temperature of the object to be cooled, the timing when the object to be cooled is cooled and passes through the maximum ice crystal formation temperature zone can be detected, and only during that period, by an appropriate impact vibration from the mechanical vibration adder, the growth of needle-shaped ice crystals that destroy the cells of the fresh food is finely crushed each time, and by suppressing cell destruction by the needle-shaped ice crystals, the amount of drip that flows out when the frozen food is thawed is reduced, and it becomes a freezing treatment apparatus for fresh food that maintains texture, taste, and nutrition.

[0045] Also, "by continuously receiving mechanical impact vibration at a cycle of 60 times or more and 600 times or less per minute, the entire object to be cooled receives impact vibration with a uniform and predetermined gravitational acceleration due to its own weight, and ice crystals growing inside the cells of the object to be cooled of the fresh food are finely crushed by the impact vibration, and damage to the cell wall can be suppressed, and it is possible to reduce the outflow of drip after thawing. Also, when the mechanical vibration is less than 60 times per minute, the ice crystals grow larger than the cell size, and the suppression effect is lost. Also, when the mechanical vibration is more than 600 times per minute, due to the elasticity of the object to be cooled of the relatively soft fresh food, the impact vibration is absorbed by the surface, so the effect is halved." Although described as the effect in the first aspect of the present invention, further, if it is a cycle of 60 times or more and 600 times or less per minute, it becomes possible to use a mechanical impact vibration mechanism such as an electromagnetic solenoid mechanism or an electric cam mechanism, which is simple and inexpensive in terms of manufacturing cost and is advantageous.

[0046] Further, the freezing treatment apparatus for the object to be cooled of fresh food according to the sixth aspect of the present invention is the freezing treatment apparatus for the object to be cooled of fresh food described in the fifth aspect, wherein the Mechanical shock and vibration adder has a function of adding mechanical shock vibration that lifts a detachable loading container on which the object to be cooled is placed at a height of 1 mm or more and 10 mm or less and then drops it with gravitational acceleration, and relates to a freezing treatment apparatus for fresh food.

[0047] According to this freezing treatment apparatus, when the height of lifting the object to be cooled is 1 mm or more and then dropping it, the shock vibration due to gravitational acceleration is evenly transmitted to the whole of the object to be cooled, and the ice crystals growing inside the cells of the object to be cooled of fresh food are finely crushed by the shock vibration, so that damage to the cell membrane can be suppressed and the outflow of drip after thawing can be reduced. Also, by setting the lifting height to 10 mm or less, damage to the outer surface layer of the soft and relatively weak object to be cooled of fresh food can be prevented. Furthermore, a mechanical shock vibration mechanism such as an electromagnetic solenoid mechanism or an electric cam mechanism can be used, which is a shock vibration range impossible with electromagnetic fields or ultrasonic waves, and it is inexpensive and advantageous in terms of manufacturing cost.

Effect of the Invention

[0048] As described above, when freezing fresh food, an apparatus having a freezing function, a function of adding appropriate mechanical shock vibration, and a function of detecting the temperature of the food to be frozen. When the fresh food is cooled and frozen, as the water inside the cells of the fresh food begins to freeze and the ice crystals grow and pass through the maximum ice crystal formation temperature zone, by continuously applying a predetermined mechanical shock vibration in the predetermined gravitational direction at a predetermined period and intensity, the growth of needle-shaped ice crystals that destroy the cells of the fresh food is finely crushed each time, suppressing damage to the cell membrane caused by the needle-shaped ice crystals. It is also a freezing treatment method and apparatus for fresh food designed to be released from the annoyance of impact noise, reducing the amount of drip flowing out when thawing the frozen food and maintaining the texture, deliciousness, and nutrition.

[0049] In addition, there are no problems in terms of energy saving in the rapid freezing method, and no problems with freezing quality variations caused by differences in the thickness of the frozen food materials. It also has the effect of suppressing the instability during supercooling and the growth of acicular ice crystals after supercooling is released. There is no instability in control by microwaves or electromagnetic fields, and no concern about the reproducibility of the effects like in the case of electromagnetic fields. It is not the micro-vibration caused by rolling or ultrasonic waves, etc., but the vertical rocking impact vibration utilizing gravity that can crush the ice crystals inside cells with the most effective, stable, and uniform impact intensity, reduce the amount of drip flowing out during thawing of the frozen food materials, and maintain the texture, deliciousness, and nutrition.

Brief Description of the Drawings

[0050]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0051] Hereinafter, the freezing treatment method and apparatus for fresh food materials of the present invention will be described with reference to FIGS. 1 to 5 in terms of specific embodiments. The technical scope of the present invention is not limited to these embodiments, and appropriate changes can be made as long as they do not go against the gist thereof.

[0052] FIG. 1 is a cross-sectional view showing a mechanical shock vibration adder 12 at a lower position 11 of a refrigeration processing apparatus 10 according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the mechanical shock vibration adder 12 at an upper position 13 of the refrigeration processing apparatus 10 according to the first embodiment. FIG. 3 is a graph showing the relationship between the change in the surface temperature T of the object to be cooled 14 and the cooling operation according to the first embodiment.

[0053] First, the configuration of the refrigeration processing apparatus 10 according to the first embodiment will be sequentially described with reference to FIGS. 1 to 3.

[0054] The refrigeration processing apparatus 10 includes a refrigerator main body 16 having a freezer compartment 15 in a refrigeration temperature range, a refrigeration system 17, a circulation air duct 18 through which refrigerated cold air circulates, a mechanical shock vibration adder 12 that applies shock vibration to a loading container 19 on which the object to be cooled 14 is loaded, and a control device 20.

[0055] The refrigerator main body 16 includes a heat-insulating box body 21 with an open front, a heat-insulating door 23 that can open and close the opening 22, and a freezer compartment 15 that is a space formed by the heat-insulating box body 21 and the heat-insulating door 23.

[0056] The refrigeration system 17 includes a compressor 24, a condenser 25, an expansion valve 26, and an evaporator 27.

[0057] The circulation air duct 18 is composed of an intake port 28 of the freezer compartment 15, a duct 29, an evaporator space 30 where the evaporator 27 is installed, and an outlet 31, and is configured such that cold air 33 circulates by the operation of a refrigeration fan 32 installed at the outlet 31.

[0058] The mechanical shock vibration adder 12 applies vibration to the loading container 19 on which the object to be cooled 14 is loaded, and is composed of a fixed iron core 34, a coil 35 that surrounds it, and a movable iron core 36. When the drive current from the control device 20 is received by the coil 35, the fixed iron core 34 has a magnetic force and can be driven by attracting the movable iron core 36 from the state of the lower position 11 to the state of the upper position 13.

[0059] In addition, a vibration table 38 with a fitting jig 37 that fits the loading container 19, which can be freely attached and detached, is fixed integrally to the upper part of the movable iron core 36, so that when the movable iron core 36 is driven, the vibration table 38 and the loading container 19 work together to drive the object to be cooled 14.

[0060] The control device 20 is also composed of an internal temperature sensor 39 that detects the temperature inside the freezer compartment 17 of the freezer body 16 of the freezing processing device 10, a product temperature detection means 40 such as an infrared sensor that detects the surface temperature of the items 14 to be cooled, which are fresh food ingredients placed in a removable loading container 19, and a specified timer 41, and is configured to drive the mechanical impact vibration adder 12 via the control device 20 in response to a signal detected by the product temperature detection means 40 such as an infrared sensor that detects the surface temperature of the items 14 to be cooled.

[0061] The insulated door 23 of the freezer body 16 is connected to upper and lower hinges 42 that rotate to open and close the open portion 22 of the insulated box body 21, and a soft gasket 43 is attached around the entire periphery of the insulated door 23 to block the flow of outside air into the freezer chamber 15 when the insulated door 23 is closed.

[0062] A speaker 44 is attached to the outer surface of the heat-insulating door 23, which emits a predetermined light rhythm or melody for a certain period of time in response to a signal from the control device 20. A shock support 45 for receiving shocks is provided around the vibration table 38.

[0063] Next, the operation of the refrigeration treatment device 10 having this configuration will be described.

[0064] When the power cord (not shown) of the refrigeration processing device 10 is connected to a commercial power source, the compressor 24 starts operating and the refrigerant in the refrigeration system 17 is compressed in the compressor 24, becoming high temperature and high pressure, and is then moved to the condenser 25. The high temperature and high pressure refrigerant transported to the condenser 25 is cooled by the low temperature outside air, lowering its temperature and liquefying. Next, when the refrigerant passes through the expansion valve 26, its pressure drops suddenly in the evaporator 27, causing it to vaporize, absorbing the heat of evaporation and cooling the evaporator 27. The refrigerant with its reduced pressure returns to the compressor 24, where it is compressed again, becoming high temperature and high pressure, and circulating within the refrigeration system 17.

[0065] Next, heat exchange is performed by flowing circulating air through the evaporation space 30 in contact with the outer surface of the cooled evaporator 27. The circulating air is formed by the refrigeration fan 32. Due to the drive of the refrigeration fan 32, it is blown out from the discharge port 31 into the freezer compartment 15, diffused in the freezer compartment 15, then enters the duct 29 from the intake port 28, undergoes heat exchange in the evaporation space 30 to become cold air, and forms a circulating air path 18 that leads to the refrigeration fan 32 again. That is, heat exchange is performed in the evaporator 27, and the circulating air is made into cold air 33 and blown out into the freezer compartment 15 to cool the entire freezer compartment 15 and the cooled object 14 stored therein as needed.

[0066] The temperature inside the freezer 15 is measured and controlled by the in - cabinet temperature sensor - 39 and the control device 20. For example, when controlling the in - cabinet temperature around - 25°C as shown by the in - cabinet temperature curve (a) in FIG. 3, if the set temperature in the control device 20 is set to - 25°C, when the in - cabinet temperature sensor - 39 detects - 25°C, the operation of the refrigeration system 17 and the refrigeration fan 32 can be automatically switched on / off to stably maintain - 25°C.

[0067] Next, the method of storing the cooled object 14 and the refrigeration treatment method in the refrigeration treatment device 10 will be described.

[0068] First, check whether the inside of the freezer 15 is cooled, and rotate the front heat - insulating door 23 about the hinge 42 to release the opening 22. Next, remove the detachable loading container 19 temporarily fixed by the fitting jig 37 from the vibrating table 38, load the cooled object 14 that requires refrigeration treatment into the loading container 19, and then fix the loading container 19 to the vibrating table 38 again via the fitting jig 37. After that, close the heat - insulating door 23 and press the vibration refrigeration treatment switch (not shown) of the control device 20 to start the vibration refrigeration treatment.

[0069] When the vibration refrigeration treatment is started, first, the surface temperature of the cooled object 14 is sensed by the product temperature detection means 40 such as the infrared sensor -. The cooled object 14 is cooled over time approximately in accordance with the surface temperature curve (b) of the cooled object 14 in FIG. 3.

[0070] That is, the object to be cooled 14 loaded in the loading container 19 is cooled relatively rapidly and its temperature decreases due to the ambient temperature in the freezer compartment 15 and the cold air 33 blown out from the discharge port 31 by the upper refrigeration fan 32.

[0071] Normally, freezing starts when the temperature reaches 0°C or lower. However, for the object to be cooled 14 that is fresh food, the intracellular fluid contains components such as sugar, and it does not start to freeze even when it passes through 0°C, and it may not freeze even when it passes the freezing point of the liquid. This phenomenon is called supercooling. Generally, as the cooling further progresses or with some kind of stimulus, the supercooling is eliminated, and the surface temperature rapidly rises to around 0°C, the freezing point. If this point is defined as the supercooling elimination point (K), simultaneously with the elimination of this supercooling, the water in the object to be cooled 14 starts to freeze, and the heat of solidification is taken away, so the temperature remains relatively constant during that period. This temperature range is called the maximum ice crystal formation temperature range (h), and the frozen food industry defines a frozen food as one in which the passing time (A) of this temperature range is 30 minutes or less.

[0072] After passing through this maximum ice crystal formation temperature range (h), the surface temperature of the object to be cooled 14 decreases relatively rapidly to near the temperature of the freezer compartment 15. When it approaches the temperature of the freezer compartment 15, it stabilizes approximately at that temperature, and subsequent frozen storage (B) is continuously carried out.

[0073] Here, when the vibration freezing process of the present invention has started, when the surface temperature of the object to be cooled 14 reaches near 0°C, the mechanical impact vibration applicator 12 starts to operate according to a signal from the control device 20.

[0074] That is, an electric current flows through the coil 35 of the mechanical vibration applicator 12 to generate magnetism in the fixed iron core 34, and the movable iron core 36 located at the lower position 11 is attracted upward, and the movable iron core 36 moves to the upper position 13. The object to be cooled 14, together with the vibration table 38 and the loading container 19 integrated with the movable iron core 36, also moves from the lower position 11 to the upper position 13 accordingly.

[0075] Next, by stopping the current flowing through the coil 35, the magnetism of the fixed iron core 34 disappears, so the movable iron core 36 moves downward to the lower position 11 by its own weight. Similarly, the object to be cooled 14 also moves downward from the upper position 13 to the lower position 11 together with the vibration table 38 and the loading container 19 integrated with the movable iron core 36. Although not described in the explanation, by attaching a spring or a spring as an auxiliary for falling downward, the falling movement is performed smoothly.

[0076] When it has moved downward to the lower position 11, the shock support 45 provided around the vibration table 38 collides with the lower base surface of the heat insulation box body 21 and receives it as an average shock to the entire vibration table 38, and this shock is also transmitted as a shock in the gravitational direction to the loading container 19 and the object to be cooled 14 integrated with the vibration table 38.

[0077] By repeating the on and off of the energization to this coil 35, the vibration table 38 can be applied as shock vibration in the gravitational direction, and it is also transmitted as shock vibration of vertical movement in the gravitational direction to the loading container 19 and the object to be cooled 14 integrated with the vibration table 38.

[0078] The operation of turning on and off the energization to the coil 35 is set by the control device 20 so that the mechanical shock vibration adder 12 continues to operate until the surface temperature of the object to be cooled 14 reaches around -10°C upon receiving the signal from the product temperature detection means 40 of the infrared sensor. That is, as shown in FIG. 3, the mechanical shock vibration addition time (C) is set to include the maximum ice crystal formation temperature zone passing time (A).

[0079] Also, in the setting of the control device 20, the on and off cycle of the shock vibration can be freely set, but in the first embodiment of the present invention, it is limited to a cycle setting of 60 to 600 times per minute.

[0080] Also, the height difference between the lower position 11 and the upper position 13 can be set to 1 mm or more and 10 mm or less by controlling the current flowing through the coil 35.

[0081] That is, when the surface temperature of the object to be cooled 14 is set to 0°C to -10°C during the period of applying vibration, it means passing through the maximum ice crystal formation temperature zone of -1°C to -5°C during that time period. Therefore, impact vibration can be applied during the growth of ice crystals, and the growing needle-shaped ice crystals can be broken into a fine ice crystal state by applying appropriate impact vibration each time.

[0082] It is known that ice during ice growth is very brittle and can be crushed even by a small impact that does not affect the material of fresh food ingredients. For the needle-shaped ice crystals during the growth process of the flat-placed object to be cooled 14, a uniform shock wave from above and below due to its own weight is very effective.

[0083] Also, setting the period of impact vibration to 600 times or less per minute means that at a finer vibration period than that, the relatively soft object to be cooled 14 that has not yet frozen itself acts as a buffer material and the shock wave does not spread sufficiently throughout, resulting in no effect.

[0084] Also, setting it to 60 times or more per minute means that the speed of ice crystal growth is 1 mm of growth per minute even in rapid cooling that freezes the object to be cooled 14 with a thickness of 30 mm in 30 minutes. If 60 vibrations are applied per minute, it can be crushed into crystals of 0.02 mm, and from the cell size of about 0.1 mm in diameter, the destruction of cells can be stopped with 60 impact times per minute. Conversely, when the vibration frequency is less than 60 times per minute, the ice crystals become larger, and it can be said that the effect of suppressing damage to the cell walls of fresh food ingredients cannot be fully exerted.

[0085] When setting the height of the drop impact from the upper position 13 to the lower position 11, it is necessary to consider the thickness of the object to be cooled 14 to be loaded. Considering about 1% elasticity for the object to be cooled 14, when the thickness of the object to be cooled 14 is 50 mm, a height of 1 mm or more is required. If it is made higher than 10 mm, damage to the object to be cooled 14 and a large noise that cannot be handled with sound insulation materials or the like are considered. Therefore, it is appropriate to keep the height of the drop impact below 10 mm.

[0086] Now, even when considering a drop from 10 mm, it is presumed that the impact vibration noise is quite large. However, by utilizing a soundproof wall or vibration damping material, a certain degree of soundproofing measures can be taken. Also, since the time taken to pass through the maximum ice crystal formation temperature zone is considered to be less than one hour, it can be said that during that time, it is heard as the cooking sound during the freezing process and is not overly bothersome.

[0087] However, in order to mask the high-pitched and monotonous impact vibration noise, it is also necessary to generate a packing-like sound in a rhythm that resonates with the impact vibration noise separately, or play completely different pleasant music to distract from the noise of the cooking sound. Therefore, while the impact vibration is being applied, by actively playing lively rhythm music with the speaker 44 as an active noise control effect, it will be recognized that cooking is currently in progress, and the annoyance can be eliminated.

[0088] Next, the freezing treatment apparatus 50 of the second embodiment will be sequentially described with reference to FIGS. 4 and 5. Note that the description of the same components as those of the freezing treatment apparatus 10 of the first embodiment will be omitted or simplified.

[0089] FIG. 4 is a cross-sectional view showing the mechanical impact vibration adder 52 at the lower position 51 of the freezing treatment apparatus 50 according to the second embodiment of the present invention, with a partial configuration view added as seen from the (M) direction. FIG. 5 is a cross-sectional view showing the mechanical impact vibration adder 52 at the upper position 53 of the freezing treatment apparatus 50 according to the second embodiment, with a partial configuration view added as seen from the (M) direction.

[0090] The freezing treatment apparatus 50 of the second embodiment includes a refrigerator main body 55 having a freezing chamber 54 in the freezing temperature zone, a refrigeration system 56, a circulation air duct 57 through which the refrigerating cold air circulates, a mechanical impact vibration adder 52 that applies vibration to a loading container 59 on which an object to be cooled 58 is loaded, and a control device 60.

[0091] The refrigerator main body 55, the refrigeration system 56, the circulation air duct 57, and the control device 60 have the same component configuration as those of the freezing treatment apparatus 10 of the first embodiment, and the description thereof will be omitted.

[0092] The mechanical impact vibration adder 52 adds mechanical impact vibration to the loading container 59 on which the object to be cooled 58 is loaded, and consists of a gear motor 61 and a cam 63 fixed to the tip of the rotating shaft 62. The cam 63 rotates together with the rotating shaft 62, and the gear motor 61 can change the rotation speed by inverter control.

[0093] The outer circumference of the cam 63 is in contact with the protrusion 64 of the loading container 59 on which the object to be cooled 60 is loaded, and acts to move the protrusion 64 up and down by the rotation of the cam 63. That is, the cam 64 is substantially elliptical, and the vertical distance of the protrusion 64 is determined by the difference between the long side and the short side.

[0094] The detachable loading container 59 is placed on the vibration base plate 65 at the lower part of the freezer compartment 54, and the support 66 of the vibration base plate 65 and the bearing part 67 of the loading container 59 are fitted, and the protrusion 64 of the loading container 59 and the cam 63 of the mechanical impact vibration adder 52 are installed so as to be fitted.

[0095] Also, when the freezing treatment device 50 is in the lower position 51, the impact rib 68 at the lower part of the loading container 59 is provided at a position in contact with the impact body 69 on the surface of the vibration base plate 65. That is, every time the loading container 59 moves up and down, due to the collision between the impact rib 68 and the impact body 69, impact vibration is received from below the loading container 59, and the impact vibration is transmitted to the object to be cooled 58.

[0096] Next, the operation of the freezing treatment device 50 with this configuration will be described.

[0097] Note that the freezer body 55, the refrigeration system 56, the circulation air duct 57, and the control device 60 have the same component configuration as the freezing treatment device 10 of the first embodiment, and the description of the operation will also be omitted.

[0098] The method of storing the object to be cooled 58 and the freezing treatment method of the freezing treatment device 50 will be described.

[0099] First, check whether the inside of the refrigerator 54 is cooled, remove the mating bearing portion 67 and the protrusion 64 of the loading container 59, remove the detachable loading container 59 from the vibration base plate 65, load the object to be cooled 58 that requires freezing treatment into the loading container 59, and then mate the loading container 59 with the vibration base plate 65 again via the support 66 and the cam 63. Then, press the vibration freezing treatment switch (not shown) of the control device 60 to start the vibration freezing treatment.

[0100] When the vibration freezing treatment is started, similar to the first embodiment, the object to be cooled 58 is cooled over time approximating the surface temperature curve (b) of the object to be cooled 58 in FIG. 3.

[0101] That is, the object to be cooled 58 loaded in the loading container 59 is cooled relatively rapidly and its temperature drops due to the ambient temperature in the freezer compartment 54 and the cold air blown from above.

[0102] Normally, water starts to freeze when it reaches 0°C or below. However, for the object to be cooled 58 which is fresh food, the intracellular fluid contains components such as sugar and does not start to freeze even when it passes 0°C, and may not freeze even when it passes the freezing point of the liquid. This phenomenon is called supercooling. Generally, as the cooling further progresses or due to some stimulus, the supercooling is eliminated, and the surface temperature rapidly rises to around 0°C at the freezing point. If this point is defined as the supercooling elimination point (K), simultaneously with the elimination of this supercooling, the moisture of the object to be cooled 58 starts to freeze, and the latent heat of solidification is taken away, so the temperature remains relatively constant during that period. This temperature range is called the maximum ice crystal formation temperature range (c), and a product with a passing time (A) of this temperature range of 30 minutes or less is regarded as a quick-frozen food.

[0103] After passing through this maximum ice crystal formation temperature range (c), the surface temperature of the object to be cooled 58 drops relatively rapidly to the temperature of the freezer compartment 54. When it approaches the temperature of the freezer compartment 54, it stabilizes approximating that temperature, and subsequent frozen storage (B) is continuously performed.

[0104] Here, when the vibration freezing process of the present invention is started, when the surface temperature of the object to be cooled 58 reaches around 0°C, the mechanical impact vibration adder 50 starts operating.

[0105] That is, an electric current flows through the gear motor 61 of the mechanical vibration adder 52, the rotating shaft 62 rotates, the cam 63 also rotates, and the tip of the longitudinal cam 63 pushes up the protrusion 64. As a result, the loading container 59 located at the lower position 51 moves to the upper position 53, and the object to be cooled 58 also moves from the lower position 51 to the upper position 53 accordingly.

[0106] Next, when the rotation of the rotating shaft 62 continues, there is no support hitting the protrusion 64 on the longitudinal side surface of the cam 63, and the protrusion 64 moves so as to fall all at once under its own weight due to gravity from the upper position 53 to the lower position 51. Similarly, the loading container 59 and the object to be cooled 58 integrated with the protrusion 64 also move downwards from the upper position 53 to the lower position 51.

[0107] When the loading container 59 moves downwards to the lower position 51, the impact rib 68 on the bottom surface of the loading container 59 hits the impactor 69 of the vibration base plate 65 and receives an impact. Therefore, the impact is transmitted to the loading container 59 and the object to be cooled 58 as vertical vibration in the direction of gravity on average.

[0108] By continuously flowing an electric current through the gear motor 61 of the mechanical vibration adder 52, continuously rotating the rotating shaft 62, and continuously rotating the cam 63, the loading container 59 can be vibrated up and down, and it is also transmitted to the object to be cooled 58 loaded in the loading container 59 as impact vibration of vertical movement in the direction of gravity.

[0109] The energization operation of the gear motor 61 of the mechanical vibration adder 52 is set by the control device 60 in response to the signal of the product temperature detection means 40 of the infrared sensor so that the mechanical impact vibration adder 52 continues to operate until the surface temperature of the object to be cooled 58 reaches around -10°C. That is, as shown in FIG. 3, the mechanical impact vibration addition time (C) is set to include the maximum ice crystal formation temperature zone passing time (A).

[0110] Also, with the settings of the control device 60, the rotational speed of the gear motor 61 of the mechanical vibration adder 52 can be freely set by performing inverter control on the gear motor 61. However, in the second embodiment of the present invention, the cycle is set at a rotational speed between 60 and 600 revolutions per minute.

[0111] Moreover, the height difference between the lower position 51 and the upper position 53 can be set by the difference between the long-side dimension and the short-side dimension of the cam 63, and is set to be 1 mm or more and 10 mm or less by changing the shape of the cam 63.

[0112] That is, the fact that the surface temperature of the object to be cooled 58 is set to 0°C to -10°C during the period when vibration is applied means that during that time period, it will pass through the maximum ice crystal formation temperature zone of -1°C to -5°C. Therefore, impact vibration can be applied during the growth of ice, and the growing needle-shaped ice crystals can be broken into a fine ice crystal state by applying appropriate impact vibration each time.

[0113] It is known that ice during its growth is very brittle and can be crushed even by a small impact that does not affect the material of fresh food ingredients. For the ice crystals during the growth process of the flat-placed object to be cooled 58, the uniform shock waves from above and below due to its own weight using gravity are very effective.

[0114] Incidentally, the reason for setting the number of impact vibrations to 600 times or less per minute and 60 times or more is the same as the reason described in the first embodiment, and the reason for setting the height of the drop impact from the upper position 53 to the lower position 51 to be 1 mm or more and 10 mm or less is also the same as the reason described in the first embodiment, so the explanation is omitted.

[0115] Now, in the form of the second invention, it has a structure that moves up and down on one side of the back of the loading container 59. However, as an effective height of impact vibration, it is about 2 mm to 3 mm. There are also problems in terms of structure and cost, so as an example, the lifting impact vibration on one side is adopted. A structure on both sides may be more effective and have higher reproducibility, and the lifting on one side is not limited.

[0116] Further, as an operation in the form of the first invention and the form of the second invention, when the surface temperature of the objects to be cooled 14, 58 reaches around 0 °C using the temperature detection means 40 such as an infrared sensor, the mechanical impact vibration adder 12, 52 starts operating according to signals from the control devices 20, 60, and is set to continue operating until the surface temperature of the objects to be cooled 14, 58 reaches around -10 °C.

[0117] That is, the mechanical impact vibration addition time (C) is set so as to include the maximum ice crystal formation temperature zone passing time (A) shown in Fig. 3. Even if the surface temperature is not measured by the temperature detection means 40, if the maximum ice crystal formation temperature zone passing time from past experience can be predicted, a time slightly longer than that time is set as the operation time of the mechanical impact vibration adder 12, 52 by the timer 41 and can be turned on / off by signals from the control devices 20, 60. In that case, the temperature detection means 40 such as an infrared sensor becomes unnecessary, but wasted movement of the mechanical impact vibration adder 12, 52 will occur around the maximum ice crystal formation temperature zone passing time.

Example

[0118] Next, a mechanical impact vibration adder 52 similar to the second embodiment was simply prototyped and stored frozen in a household refrigerator-freezer to evaluate the difference in drip due to the presence or absence of impact vibration in an experimental manner.

[0119] That is, a dry battery type gear motor rotating at 180 revolutions per minute was attached to the loading container, designed so that the height between the lower position and the upper position is 1 mm, and installed so that mechanical impact vibration in the gravitational direction is applied to the loading container. Therefore, mechanical impact vibration was continuously applied at a cycle of 180 times per minute. The size of the loading container was 50 mm × 50 mm × height 30 mm, and a transparent resin container with a lid was used.

[0120] As a test sample of the object to be cooled loaded in the loading container, about 30 g of konjac with dimensions of 25 mm × 30 mm × 40 mm was used. The reason is based on past experience that konjac is most reproducible and suitable for evaluating the drip amount as fresh food ingredients.

[0121] The temperature of the household freezer was about -20°C. Konjac was loaded into a loading container equipped with a mechanical shock vibration adder, and with the dry battery type motor operating, that is, with mechanical shock vibration applied, it was placed in the freezer for 4 hours to confirm the freezing of the konjac. Next, it was left at room temperature for 4 hours to thaw.

[0122] As the control group, the same containers and test samples that were not subjected to shock vibration were installed in the same freezer, and after 4 hours of freezing time and 4 hours of room temperature thawing time, the drip amounts were compared and evaluated. The same evaluation experiment was repeated 5 times with different test samples.

[0123] As a result, the average drip amount in the group with shock vibration added was 30% (39%, 27%, 27%, 30%, 26%), while in the freezing process of the control group without shock vibration added, an average drip amount of 40% (51%, 41%, 31%, 36%, 34%) was measured. In all 5 simultaneous comparison results, those with shock vibration added showed superiority in the drip amount, and it was confirmed that the effect of shock vibration was obvious.

[0124] This evaluation result is based on the shock vibration frequency of 180 times per minute, with the height difference between the lower position and the upper position being 1 mm, and the evaluation is at a relatively weak level of shock vibration in the gravitational direction. It can be judged that by increasing the height, the drip amount suppression effect will be enhanced.

[0125] Also, in this example, it was an evaluation in a household refrigerator-freezer, and it was a comparative evaluation by a slow freezing method only installed in the -20°C freezer compartment. However, there is also a possibility of a synergistic effect in the cooling by the rapid freezing method, or in combination with cooling treatment methods using supercooling, electromagnetic fields, microwaves, or ultrasonic waves, and it is not limited to the slow freezing method.

Industrial Applicability

[0126] When freezing fresh food materials, an apparatus having a freezing function, a function of adding appropriate mechanical impact vibration, and a function of detecting the temperature of the food materials to be frozen. In the process of passing through the maximum ice crystal formation temperature zone during cooling and freezing, by continuously applying impact vibration in a predetermined mechanical gravity direction at a predetermined cycle, the growth of acicular ice crystals is finely crushed each time, and cell destruction by acicular ice crystals is suppressed, thereby reducing the amount of drip flowing out during thawing of frozen food materials, and aiming at freezing treatment of fresh food materials that maintains texture, taste, and nutrition.

[0127] The present invention can be a new product of household, commercial, and industrial refrigerators with a mechanical impact vibration adder installed in the refrigerator, or can be commercialized as an externally attachable mechanical impact vibration adder for existing refrigerators.

Explanation of Signs

[0128] 10, 50 ··· Freezing treatment device, 11, 51 ··· Lower position, 12 ··· Mechanical impact vibration adder, 13, 53 ··· Upper position, 14, 58 ··· Object to be cooled, 15, 54 ··· Freezing chamber, 16, 55 ··· Refrigerator body, 17, 56 ··· Refrigeration system, 18, 57 ··· Circulation air duct, 19, 59 ··· Loading container, 20, 60 ··· Control device, 21 ··· Heat insulation box body, 22 ··· Open part, 23 ··· Heat insulation door, 24 ··· Compressor, 25 ··· Condenser, 26 ··· Expansion valve, 27 ··· Evaporator, 28 ··· Intake port, 29 ··· Duct, 30 ··· Evaporator space, 31 ··· Exhaust port, 32 ··· Refrigeration fan, 33 ··· Cold air, 34 ··· Fixed iron core, 35 ··· Coil, 36 ··· Movable iron core, 37 ··· Fitting jig, 38 ··· Vibration table, 39 ··· Temperature sensor, 40 ··· Product temperature detection means, 41 ··· Timer, 42 ··· Hinge, 43 ··· Gasket, 44 ··· Speaker, 45 ··· Impact support, 52 ··· Mechanical impact vibration adder, 61 ··· Gear motor, 62 ··· Rotating shaft, 63 ··· Cam, 64 ··· Protrusion, 65 ··· Vibration base plate, 66 ··· Support, 67 ··· Bearing part, 68 ··· Impact rib, 69 ··· Impact element 69.

Claims

1. A method for freezing fresh food materials, characterized in that when a fresh food material is cooled to pass through a maximum ice crystal formation temperature zone and then frozen and stored at a temperature below said maximum ice crystal formation temperature zone, said material is cooled and frozen by continuously applying mechanical shock vibrations at a predetermined cycle, lifting said material to a predetermined height and lowering it by the force of gravitational acceleration only during the process in which said material is maintained at a temperature including said maximum ice crystal formation temperature zone.

2. 2. The method for freezing fresh food materials according to claim 1, characterized in that the cooling / freezing process is carried out by continuously applying the mechanical impact vibration, which lifts the object to be cooled, which is a fresh food material, to a predetermined height and then lowers it using the force of gravitational acceleration, at a cycle of 60 times or more per minute and 600 times or less per minute.

3. 3. A method for freezing fresh food materials as claimed in claim 1 or claim 2, characterized in that the cooling / freezing process is carried out by lifting the object to be cooled, which is a fresh food material, to a predetermined height and then lowering it by the force of gravitational acceleration, the predetermined height of the mechanical shock vibration being 1 mm or more and 10 mm or less.

4. A method for freezing fresh food materials, characterized in that when a cooled object, which is a fresh food material, is cooled to pass through a maximum ice crystal formation temperature zone and frozen and stored at a temperature below said maximum ice crystal formation temperature zone, said frozen object is subjected to continuous mechanical shock vibration at a predetermined cycle, which lifts said cooled object to a predetermined height and lowers it with gravitational acceleration, while playing a rhythm or melody at a predetermined comfortable volume, only during the process in which said cooled object is maintained at a temperature including said maximum ice crystal formation temperature zone.

5. a mechanical shock vibration adder having a function of lifting the removable loading container carrying the item to be cooled to a predetermined height and lowering it by the force of gravitational acceleration to add mechanical shock vibration in the direction of gravity; and a product temperature detection means having a function of detecting an approximate temperature of the item to be cooled from the surface temperature of the item to be cooled, wherein, during cooling by the freezing function, a control device drives the mechanical shock vibration adder to apply a predetermined mechanical shock vibration in the direction of gravity continuously at a frequency of 60 times or more per minute and 600 times or less per minute when the temperature of the item to be cooled is detected by a signal from the product temperature detection means and the water within the cells of the item to be cooled passes through a maximum ice crystal formation temperature range in which ice crystals grow.

6. 6. The freezing processing device for fresh food materials according to claim 5, wherein the mechanical impact vibration adder, which applies a predetermined mechanical impact vibration in the direction of gravity, has a function of adding mechanical impact vibration that lifts the material to a predetermined height of 1 mm or more and 10 mm or less and then lowers it with the acceleration of gravity.

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