JP2017227371A - Food storage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a food storage capable of achieving improvement in shelf life of food by maintaining airtightness in a storage chamber and keeping a gas composition at target concentration.SOLUTION: A food storage includes: a storage chamber 1 having sealability; a door 2 opening/closing for putting in/taking out food in the storage chamber 1; door opening/closing detection means 3 for detecting opening/closing of the door 2; storage gas supply means 4 for supplying a gaseous body having an effect of enhancing shelf life of food; atmospheric pressure adjustment means 5 for adjusting the atmospheric pressure in the storage chamber 1 to be equal to or lower than 1 atmospheric pressure; and control means 7 for controlling the door opening/closing detection means 3, the storage gas supply means 4, and the atmospheric pressure adjustment means 5. The control means 7 actuates the atmospheric pressure adjustment means 5 and the storage gas supply means 4 by detecting the fact that the door is closed by the door opening/closing detection means 3, and supplies a storage gas to the storage chamber 1. Thus, when the storage gas is supplied to the storage chamber by the storage gas supply means 4, an internal pressure of the storage chamber does not exceed 1 atmospheric pressure, and storage gas concentration can be maintained constant at target concentration.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a food storage that uses a gas composition to improve the storage stability of food.

  There are a plurality of effects depending on the type of target food as an action to improve the preservability of the food using the gas composition. When the target food is vegetable, undesired changes (e.g., hardening, discoloration, softening) associated with the maturation of vegetables by reducing the respiratory activity of vegetables or reducing the effects of mature hormones, sugar as a respiratory substrate, It is to suppress changes in taste due to consumption of organic acids and low molecular weight organic components (CA action). In that case, the gas composition in the storage chamber is adjusted so as to satisfy an oxygen partial pressure of 1 to 15 kPa, a carbon dioxide partial pressure of about 1 to 20 kPa, or both. In the case of pork, chicken and white fish, the carbon dioxide partial pressure is adjusted to about 10-80 kPa (antibacterial action) in order to prevent the growth of microorganisms, and the oxygen partial pressure is adjusted to 0-18 kPa for fats and oils. It suppresses the oxidative modification of the oxidizing component (oxidation suppressing action). In the case of foods containing a lot of myoglobin such as beef thigh and red tuna, the oxygen partial pressure is adjusted to about 40 to 80 kPa, in addition to the above partial pressure of carbon dioxide, so that myoglobin is less likely to be met to maintain a bright red color. (Meto-protection action).

  In order to improve the preservability of foods even in household refrigerators, an invention using a storage room configured in an airtight state and a gas composition control means has been made. For example, there is a refrigerator that maintains the fresh red color by reducing the oxygen in the storage room where food is stored, thereby suppressing the oxidation of the food and maintaining the freshness of the food. It has been. (For example, see Patent Document 1)

JP 2012-37201 A

  However, the conventional configuration has a problem that it is difficult to maintain airtightness in the storage chamber when increasing the gas concentration or increasing the temperature in the storage chamber for thawing. The cause of the problem is that the pressure inside the storage chamber increases due to the operating conditions after the storage chamber is sealed in an airtight state.

  Specifically, 1. introducing gas into a closed storage chamber; 2. Heat derived from food is released into the storage room or heating the storage room; The atmospheric pressure in the storage chamber increases due to three factors: the evaporation of water in the food and the generation of water vapor pressure. As a result, there arises a problem that the airtightness of the storage chamber cannot be maintained and the gas concentration cannot be maintained constant.

  The present invention aims to improve the preservability of food by coping with the above three factors to maintain the gas tightness of the storage chamber and maintain the gas composition at the target concentration.

In order to solve the above-described conventional problems, the food storage of the present invention includes a hermetically sealed storage room, a door that opens and closes to put food in and out of the storage room, and a door open / close detection that detects opening and closing of the door. Means, a storage gas supply means for supplying a gas having an effect of improving the storability of the food, an atmospheric pressure adjusting means for adjusting the atmospheric pressure of the storage chamber to 1 atmosphere or less, the door opening / closing detection means, and the storage gas supply And control means for controlling the atmospheric pressure adjusting means, the control means detects that the door is closed by the door opening / closing detection means, and operates the atmospheric pressure adjusting means and the storage gas supply means to The storage gas is supplied to the storage room.

  Thus, when food is put into the storage chamber and the door is closed, the storage gas is supplied to the storage by the storage gas supply means. At that time, the internal pressure of the storage chamber does not exceed 1 atm by operating the atmospheric pressure adjusting means.

  The food storage according to the present invention can prevent the atmospheric pressure in the storage chamber from being increased by any of the factors of introducing gas into the closed storage chamber, heating of the gas in the storage chamber, and water vapor pressure. As a result, it is possible to maintain the airtightness of the storage chamber and keep the storage gas concentration constant at the target concentration.

Sectional drawing of the food storehouse by Embodiment 1 of this invention The flowchart which shows control of the food storage by Embodiment 1 of this invention Sectional drawing of the storage chamber of the food storehouse by Embodiment 1 of this invention Sectional drawing of the food storehouse by Embodiment 2 of this invention (A) Pressure change diagram of the storage chamber of the food storage according to the second embodiment of the present invention, (B) Pressure change diagram of the storage chamber of the food storage according to the second embodiment of the present invention. Sectional drawing of the food storehouse by Embodiment 3 of this invention

  The invention according to claim 1 is a storage room having a sealing property, a door that opens and closes to put food in and out of the storage room, a door open / close detection means that detects opening and closing of the door, and a preservability of the food. A storage gas supply means for supplying a gas having an effect of increasing pressure, an atmospheric pressure adjustment means for adjusting the atmospheric pressure of the storage chamber to 1 atmosphere or less, a door opening / closing detection means, the storage gas supply means, and the atmospheric pressure adjustment means. Control means for controlling, and the control means detects that the door is closed by the door opening / closing detection means, and operates the atmospheric pressure adjustment means and the storage gas supply means to supply the storage gas to the storage chamber. Thus, when food is put into the storage chamber and the door is closed, the storage gas is supplied to the storage by the storage gas supply means. At this time, by operating the atmospheric pressure adjusting means, the internal pressure of the storage chamber does not exceed 1 atmospheric pressure, and the storage gas concentration can be kept constant at the target concentration.

  The invention according to claim 2 is the invention according to claim 1, further comprising a cooling means for cooling the storage chamber, and the control means detects the door closed by the door opening / closing detection means, By operating the cooling means to cool the storage chamber, when hot food is charged in the storage chamber maintained at a low temperature and the door is closed, heat is transferred from the input heat load to the gas in the storage chamber. To do. When the storage is strongly cooled by the cooling means, the heat moves quickly to the outside of the storage, and it is possible to suppress the expansion of the gas in the storage chamber, and it is possible to more reliably maintain the storage gas concentration at the target concentration. It becomes.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, there is provided a door opening / closing prediction means for predicting a door opening / closing timing based on detection information of the door opening / closing detection means, and the control means By operating the cooling means at a predetermined timing predicted by the door opening / closing predicting means to cool the storage chamber, when the time period during which the door is opened / closed is predicted, the storage room is normally The temperature is adjusted to a lower temperature. After that, when a heat load due to food is applied as expected, it becomes possible to equilibrate with the heat quantity of the storage room which has been lowered, and to maintain the storage gas concentration at the target concentration more reliably.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, the storage gas supply means supplies a storage gas having a temperature lower than the room temperature of the storage chamber, thereby lowering the temperature. The food (heat load) in which the gas is added is quickly cooled to a temperature equivalent to the average room temperature of the storage room. Therefore, it is possible to prevent the food from expanding the gas in the storage chamber after the atmospheric pressure is adjusted to 1 atm or less by the atmospheric pressure adjusting means.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein the pressure adjusting means is a pressure reducing means for reducing the pressure in the storage chamber, and the control means is the door opening / closing detection means. After detecting that the door is closed, the decompression means is operated to decompress the inside of the storage, and then the preservation gas supply means is operated to introduce the preservation gas, whereby food is introduced into the storage chamber and the door is opened. When is closed, the pressure is reduced by the pressure reducing means. The degree of depressurization is made equal to or greater than the pressure increase due to the supply of the storage gas. Thereafter, even if the preservation gas is supplied to the storage chamber, the atmospheric pressure in the storage chamber becomes 1 atm or less.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, further comprising a pore closing means for reducing a pore opening degree of the vegetable, wherein the control means is controlled by the door opening / closing detection means. After detecting that the door is closed, by operating the pore closing means to reduce the pore opening of the vegetables, in addition to improving the freshness due to the preservation gas, it further enhances the freshness by suppressing the transpiration due to the closed pores be able to.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the storage chamber has moisture absorption means for absorbing water vapor evaporated and evaporated from the food, thereby evaporating from the vegetables. Moisture that is absorbed is absorbed, and an increase in water vapor pressure is suppressed. As a result, it is possible to suppress an increase in atmospheric pressure from the time point adjusted by the atmospheric pressure adjusting means.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 shows a cross-sectional view from the side of the food storage of this embodiment. A storage chamber 1 that contains food and has airtightness, a door 2 that opens and closes to put food in and out of the storage chamber 1, door open / close detection means 3 that detects opening and closing of the door 2, and storage stability of the food A storage gas supply means 4 for supplying a gas having an effect of increasing the pressure, an atmospheric pressure adjustment means 5 for adjusting the atmospheric pressure of the storage chamber 1 to 1 atm or less, a cooling means 6 for changing the temperature in the storage chamber, The door opening / closing detection means 3, the storage gas supply means 4, the atmospheric pressure adjustment means 5, and the control means 7 for controlling the cooling means 6, and the storage chamber 1, the storage gas supply means 4, and the cooling means 6 are insulative. Are housed in a housing 8 and a housing door 9. A temperature sensor (not shown) for measuring the temperature of the gas is provided in the storage chamber 1, and the detection information is sent to the control means 7. Moreover, the pore closing means 10 which reduces the pore opening degree of vegetables in the storage chamber 1 is provided. The atmospheric pressure adjusting means 5 in the present embodiment is an atmospheric pressure adjusting valve that releases an internal gas to the outside of the storage chamber 1 when the atmospheric pressure in the storage chamber 1 becomes higher than 1 atmospheric pressure. Further, the cooling means 6 cools to a temperature lower than the temperature outside the housing 8. The control means 7 includes a timer, and based on the detection information of the door opening / closing detection means 3 and the time information of the control means 7, the door opening / closing prediction means for predicting by learning the time zone in which food is often introduced is controlled. It shall be prepared inside.

In order to adjust the gas concentration in the storage chamber 1 to the target gas concentration, when the gas adjusted to the target gas concentration is supplied by the storage gas supply means 4, the concentrated carbon dioxide gas or oxygen concentration is the target concentration. In some cases, a predetermined amount of oxygen gas having a lower concentration is supplied and mixed with the atmosphere in the storage chamber 1 to adjust the target gas concentration. The latter has the merit that the operation of the storage gas supply means 4 can be reduced and the operating energy and the durability of the consumable member can be increased. In the description of the present embodiment, the latter is used.

  Specific examples of the storage gas supply means 4 include a gas cartridge that compresses and stores the gas, an electrochemical device that electrochemically removes oxygen and selectively permeates carbon dioxide, and a material containing carbon is oxidized. By means of redox devices that generate carbon dioxide or reduce oxygen-containing materials to generate oxygen, membrane materials with high oxygen and carbon dioxide permeation rates, physical fractionation devices such as molecular sieves, microorganisms and enzymes There are biological devices that consume oxygen and generate carbon dioxide.

  When the storage gas supply means 4 is a gas cartridge, a gas remaining display means (not shown) for displaying the residual pressure or amount in the gas cartridge in the middle of the flow path connecting the storage gas supply means 4 and the storage chamber 1. ) Is visibly installed from the outside of the housing door 9 or the housing 8. As a result, the user can visually recognize the remaining stored gas and determine the replacement timing.

  The operation of the food storage when the food such as vegetables is put into the storage room 1 will be described using the flowchart of FIG. The time when the door 2 is opened by the door opening / closing detection means 3 is detected (STEP 1 to 3), and the gas composition in the storage chamber 1 is estimated based on the door opening time. For example, when opening of a door for a predetermined time or more is detected, it is assumed that the gas in the storage chamber 1 is about 20 kPa oxygen and about 0.4 kPa carbon dioxide, which are the same as the atmospheric composition. Based on the estimated gas composition, the storage gas supply amount is determined (STEP 4). Further, the control means 7 estimates the input thermal load based on the temperature change information of the temperature sensor. When it is estimated that a heat load of a predetermined amount or more is estimated, it is determined that food has been input, and the amount of gas determined above is introduced from the storage gas supply means 4 (STEP 5a). At that time, the atmospheric pressure adjusting means 5 is activated, and the internal gas exceeding 101 kPa (1 atm) is released to the outside of the storage chamber, and the atmospheric pressure in the storage chamber 1 is kept at 101 kPa to prevent the door 2 from opening. Moreover, the cooling of the storage chamber 1 is started by the cooling means 6 with a capacity higher than that during stable operation (STEP 5b). Thus, the action of the heat of the food warming the gas in the storage chamber to increase the atmospheric pressure is weakened, and the atmospheric pressure adjusting means 5 is actuated many times to prevent the stored gas from leaking out of the storage chamber 1 wastefully. When the storage chamber reaches a predetermined temperature (STEP 7b), the powerful operation of the cooling means 6 is stopped and the normal temperature adjustment operation control is resumed (STEP 8).

  Alternatively, during the time period predicted by the door opening / closing prediction means, the cooling by the cooling means 6 may be strengthened in advance to keep the storage chamber 1 at a lower temperature than during stable operation. In this case, compared with the above, since the heat load input in a shorter time can be cooled, there is less possibility that the pressure in the storage chamber 1 due to the heat load is increased.

  As another means for cooling the heat load in a shorter time, there is a method of supplying a storage gas having a temperature lower than that during the stable operation of the storage chamber 1 from the storage gas supply means 4. This can be realized by arranging the storage gas supply means 4 in a relatively low temperature part in the housing 8 or by arranging a flow path connecting the storage gas supply means 4 and the storage chamber 1 in a relatively low temperature part. In addition, when the stored gas supply means 4 uses a gas compressed and stored, the heat load can be rapidly cooled by storing the compressed gas at a temperature below the storage chamber 1 and supplying the compressed gas at a low temperature by expansion. it can. As a result, it is possible to further reduce the risk that the pressure in the storage chamber 1 is increased due to the heat load.

  Since the preservation gas supply means 4 consumes energy or consumes members for operation, it is preferable to reduce the supply amount of the preservation gas from the viewpoint of energy saving and durability.

In the storage chamber 1, the introduction part of the storage gas supply means 4 and the discharge part by the atmospheric pressure adjustment means 5 are provided as far apart as possible, so that wasteful discharge of the storage gas can be reduced. For example, when the direction of arrow A is the largest longitudinal direction, it is preferably provided near both ends thereof or near the diagonal of the storage chamber 1. In this case, the flow rate when introducing the storage gas from the storage gas supply means 4 is determined in consideration of the Reynolds number and the distance between the introduction part and the discharge part so as not to cause laminar flow. By preventing the occurrence of gas concentration unevenness in the storage chamber 1 in this way, it is possible to minimize the waste of the introduced storage gas being discharged without being used for storage.

  For the same purpose, when a preservation gas having a temperature lower than the temperature in the storage chamber 1 is supplied, the introduction portion is provided at the lowest position in the storage chamber 1 and the discharge portion is provided at the highest position, so that the specific gravity is heavy. It is even better to introduce a preserving gas from the bottom and selectively discharge the existing gas (atmosphere) having a low specific gravity. On the other hand, when supplying a preservation gas having a temperature higher than that in the storage chamber 1, the positional relationship between the two may be reversed to selectively discharge the heavy specific gravity atmosphere.

  Moreover, the gas supply amount required in order to express a predetermined freshness maintenance effect can be reduced by using together with physiological activity reduction means other than gas, and suppressing deterioration of a food from many aspects by a several principle. For example, low temperature damage does not occur when vegetables and fruits and vegetables that are susceptible to low temperature damage are stored at a lower temperature than usual in the presence of a storage gas. In cold injury, a specific enzyme activity is induced by cold stress, and the cell membrane is damaged. It is known that when physiological activity is reduced under the action of CA by a storage gas, enzyme activity is not induced and low-temperature damage can be suppressed. For example, when the minimum storage temperature is 5 ° C. in the absence of CA, the food can be stored at a low temperature of 0 to 3 ° C. under the action of CA. Since the physiological activity can be expected to be reduced by low temperature, the storage gas supply amount necessary for expressing the same level of freshness maintaining effect can be reduced as compared with the case of using the CA action alone.

  In addition, some vegetables and fruits and vegetables can induce a physiological defense physiological effect by applying a low temperature shock at the initial stage of storage, and the low temperature tolerance may be improved. For example, if the minimum storage temperature when no storage gas is used is 8 ° C., a physiological action that exhibits low-temperature tolerance is induced by cooling to about 0 ° C. for about half a day, and then the storage gas is introduced 3 It can be stored at ~ 5 ° C. In that case, the specific gravity of the freshness maintenance effect by low temperature becomes still higher, and compared with the case where it uses only CA action | operation alone, the storage gas supply amount required in order to express the freshness maintenance effect of the same level can be reduced.

  As another physiological activity reducing means that can be used in combination, there is a method of reducing the stomatal opening of vegetables by irradiating red light or near infrared light. By reducing the opening of the pores, it is possible to suppress the transpiration of water or to suppress breathing. If the transpiration is high, the vegetables are dried and wilted, and further, the enzymes that damage the cell walls are induced by the drying, and the tissue is softened. In addition, when breathing becomes active, physiological activity is generally enhanced, and aging progresses or useful components decrease. Plants have large pore openings during the day to promote photosynthesis, but evolved to close the pores when exposed to red light in the evening. Utilizing this property, the surface of the foliar and the stagnation with many pores is irradiated with red light of about 800 to 900 nm every several hours to every few days for 30 minutes to several hours to make the pores more Can be closed. Exposure of these stimulating components by means of active oxygen or ozone generating means can also reduce the opening of the pores due to the biological defense reaction. By using these means and the storage gas in combination, it is possible to reduce the supply amount of the storage gas necessary for exhibiting the same level of freshness maintaining effect as compared with the case where the CA action is used alone.

If the pores of vegetables and fruits are large during storage, problems may occur from the viewpoint of hermeticity. The water vapor pressure generated by transpiration increases the internal pressure of the storage chamber 1. For example, in the case of 5 ° C., the saturated water vapor pressure is 0.87 kPa, and when the inside of the storage chamber 1 is 101 kPa and the water vapor pressure before adding food is zero, the total pressure increases by about 1%. As a result, the gas tightness of the storage chamber 1 is broken and the storage gas may leak out. By suppressing the increase in water vapor pressure by the pore opening reduction means, it can be expected that the CA action by the storage gas is more reliably exhibited. Alternatively, the same effect can be expected by removing a water vapor generated by arranging a sufficient amount of members having a moisture adsorption action in the storage chamber 1. By using these means and the storage gas in combination, it is possible to ensure the sealing property of the storage chamber 1 more reliably than in the case where the CA action is used alone.

  While storing vegetables and fruits and vegetables, although the respiratory activity is reduced by the CA action, the breathing does not become zero, and the gas composition in the storage chamber 1 gradually changes due to the breathing of food. For example, when a large amount of vegetables having a relatively high respiration rate is added, the oxygen partial pressure is further reduced and the carbon dioxide partial pressure is further increased as compared with the initial storage gas partial pressure. The change can reach several kPa in 1-2 days. If the oxygen partial pressure falls below 1 kPa or the carbon dioxide partial pressure exceeds 15 kPa, anaerobic breathing (fermentation) may occur instead of normal aerobic breathing, which may adversely affect the flavor of vegetables and fruits and vegetables. Occurs. Therefore, even if the gas composition changes due to respiration by vegetables, there is a need to maintain a gas partial pressure that does not cause anaerobic respiration.

  The rate of change of the gas composition varies depending on the type and amount of vegetables stored in the storage room 1 and the initial freshness. An image recognizing means 11 for photographing the stored items is installed in the storage chamber 1, and a change in gas composition is predicted from the type and amount of vegetables stored based on the image data and the database. Based on the prediction, adjustment is made by reducing the amount of gas supplied from the storage gas supply means 4 so as not to cause anaerobic breathing during a general storage period (1 to 2 weeks). Or you may open | release the atmospheric pressure adjustment means 5 and introduce external air at the timing before the gas in the storage chamber 1 may cause anaerobic breathing based on prediction.

  Further, in order to improve the accuracy of the change prediction, the change prediction is made by combining the detection information of the weight measuring means for measuring the weight of the stored item in the storage chamber 1 and the gas measuring means for measuring the gas partial pressure in the storage chamber 1. May be. Regarding information processing of the image recognition means 11, recognition work and prediction calculation may be performed using a computer connected to a network or cloud computing.

  On the other hand, for the purpose of making the configuration for preventing anaerobic breathing simple and compact, the open portion of the storage chamber 1 may be enlarged according to the weight of the stored items in the storage chamber 1. For example, the food storage part 12 of the storage chamber 1 in FIG. 3 floats via the spring structure 13. In proportion to the storage weight, the communication part B of the slit 14 provided on the side surface of the food storage unit 12 and the slit 15 provided on the side surface of the storage chamber 1 expands, and the outside air easily diffuses into the storage chamber 1. . As a result, the amount of oxygen consumed by the respiration of food and the amount of oxygen supplied by diffusion are generally balanced, and the gas concentration composition in the storage chamber 1 can be kept constant and apparently unchanged. In this way, it is possible to suppress the adverse effect of a decrease in oxygen partial pressure with a simple configuration.

  When the food is taken out, a part of the preservation gas mixed to the target concentration leaks out of the storage chamber 1 by opening the door 2. If the door 2 is opened frequently and the storage gas is supplied again each time, there arises a problem that the storage gas supply means 4 increases the energy consumption and member consumption and shortens the durable life. In order to cope with this problem, the remaining concentration of the storage gas in the storage chamber 1 is predicted based on the length of time that the door 2 is opened by the door opening / closing detection means 3, and the operation time of the storage gas supply means 4 is determined. Minimize. Gas leakage in the storage chamber 1 is mainly diffused by natural convection when the storage chamber 1 is cooled or heated by the temperature adjusting means, and is mainly diffused when the temperature difference from the outside of the storage chamber is small. Caused by. The influence of the length of the opening time and the temperature difference between the inside and the outside on the residual gas concentration after closing the door is obtained in advance and stored in the control means 7. Based on the information obtained by the door opening / closing detection means 3 and the second temperature measurement means for measuring the temperature outside the food storage, it is determined how long the storage gas supply means 4 needs to be operated after the door is closed. To do.

Further, in order to cope with the above-described problems caused by frequent storage gas supply, the door opening / closing predicting means predicts the time period when the door 2 is opened frequently and the time period when the door 2 is opened frequently to control the supply of the storage gas. To do. The CA action, antibacterial action, and oxidation-inhibiting action on foods often require about 1 hour before the effects are manifested. Therefore, in the time zone that is frequently opened and closed once or more hours, even if the storage gas is introduced, the above effect is small, and the storage gas supply means 4 is not operated.

  In a time zone in which the switching frequency is predicted to be less than once / hour, only the physiological activity reducing unit is operated without operating the storage gas supply unit 4 in a time zone with a relatively high switching frequency. In a relatively infrequent time zone, the preservation gas supply means 4 alone or in combination with the physiological activity reduction means is used to maintain freshness by a plurality of actions.

  Alternatively, the storage gas supply means 4 is operated so as to adjust the concentration to be relatively close to the atmosphere within the concentration range in which the CA action is exerted during a high opening frequency period, and compared during a low frequency period. The storage gas supply means 4 may be operated so as to adjust the concentration far from the target atmosphere. For example, the gas concentration in the storage chamber 1 is adjusted to a carbon dioxide partial pressure of 1 to 20 kPa during a time period when the door is open and closed, and a carbon dioxide partial pressure of 0.04 to 1 kPa during a time when the door is open and closed. adjust. Further, the oxygen partial pressure is adjusted to 2 to 18 kPa during the time when the door is open and closed, and the oxygen concentration is adjusted to 18 to 21 kPa during the time when the door is open and closed. By this control, the substantial operation time of the storage gas supply means 4 can be shortened, and the above problem can be suppressed.

  Further, based on the above door opening / closing time zone prediction, when shifting from a low door opening frequency zone to a high frequency zone, the storage gas supply means 4 may be operated in reverse to recover the storage gas. Good. For example, when the storage gas supply means 4 is an electrochemical device or a physical fractionation device that selectively transmits gas, the recovered carbon dioxide or oxygen is temporarily accumulated in the device or transferred to another chamber. To do. The stored gas that has been accumulated or transferred is transferred again to the storage chamber 1 when shifting from a time zone with a high door opening frequency to a time zone with a low frequency. As a result, the energy consumption of the storage gas supply means 4 can be reduced, the durability life can be extended, and the gas in the storage chamber 1 can be adjusted to the target concentration in a relatively short time.

(Embodiment 2)
FIG. 4 is a cross-sectional view of the food storage in this embodiment. Since the operation of the food storage in this embodiment has many parts in common with the first embodiment, description of the common parts is omitted, and only different parts are described below.

  The storage gas supply means 4 is provided outside the housing 8 having heat insulation properties. The atmospheric pressure adjusting means 5 is a decompression means 5 for decompressing the inside of the storage chamber.

  FIG. 5A shows a change in atmospheric pressure in the storage chamber 1 in the present embodiment. When the food is put into the storage chamber 1 and the door opening / closing detection means 3 detects that the door is closed, the control means 7 operates the decompression means 5 to exhaust the gas in the storage chamber 1. The decompression means 5 exhausts by the amount of the partial pressure (volume) of the storage gas introduced by the storage gas supply means 4 (ab). Next, when exhaust is completed, the control means 7 operates the storage gas supply means 4 to supply the storage gas (b to c). At this time, since the gas having the partial pressure of the storage gas has already been exhausted, the storage chamber 1 becomes 1 atm. However, when the storage chamber 1 is cooled by the cooling means 6, the storage gas is at a higher temperature, so that when the storage chamber 1 is cooled by the amount of heat in the storage chamber 1, the volume contracts (cd), and the storage chamber 1 The inside air pressure becomes 1 atm or less, and the door 2 is strongly pressed against the storage chamber 1. In this way, the hermeticity of the storage chamber 1 is maintained, the concentration of the storage gas is maintained at a constant value, and reliable freshness can be maintained (d˜).

FIG. 5B shows another usage of the decompression means. In the above, when the decompression means 5 is operated (a ′ to b ′), the interior of the storage chamber 1 is exhausted to a value equal to or greater than the partial pressure (volume) of the preservation gas introduced by the preservation gas supply means 4. When exhausting, evaporation of water droplets on the surface of food such as vegetables is promoted by decompression, and the heat of vegetables is taken away by latent heat of evaporation. As a result, the food can be brought close to the stable temperature of the storage chamber 1 quickly, and the freshness of the food is maintained. As a result, the ratio of freshness maintenance by an action other than CA increases, and the supply amount of the storage gas supply means 4 can be reduced.

  In addition, oxygen gas and ethylene gas that existed in foods such as vegetables can be discharged by reducing the pressure, so that the oxygen that acts directly inside the foods can be reduced to make the CA effect easier, and aging by ethylene It can be suppressed. As a result, it is possible to reduce the supply amount of the storage gas necessary for demonstrating the preservation performance of a certain vegetable, and it is possible to improve the durability and energy saving performance of the storage gas supply means 4. In order to strengthen this action, the decompression means 5 may be operated a plurality of times to repeat the decompression.

  Next, when the exhaust is completed, the control unit 7 operates the storage gas supply unit 4 to supply the storage gas (b ′ to c ′). After the supply is completed, the pressure in the storage chamber 1 is 1 atm (101 kPa) or less (c ′), and the oxygen partial pressure in the storage chamber 1 is 21 kPa or less, which is lower than the atmosphere. Therefore, when the storage gas supply means supplies a gas having a low oxygen concentration (for example, nitrogen) in order to adjust the oxygen to a predetermined target partial pressure, the supply amount of the storage gas supply means can be reduced. Further, if the initial oxygen partial pressure is reduced as described above, the low partial pressure oxygen and the high partial pressure carbon dioxide act on the CA in concert, so that the supply amount of carbon dioxide can be reduced. Therefore, it is possible to reduce the supply amount of the storage gas supply means 4 necessary for exhibiting a certain vegetable storage performance.

(Embodiment 3)
FIG. 6 is a cross-sectional view of the food storage in the third embodiment. Since the operation of the food storage in this embodiment has many parts in common with the first embodiment, description of the common parts is omitted, and only different parts are described below.

  In addition to the storage room 1, a second storage room 16 for storing vegetables and fruits and vegetables and a blower means 17 for transferring gas from the second storage room 16 to the storage room 1 are provided, and stored in the gas in the second storage room The storage gas supply means 4 may be operated after the chamber 1 is filled. In that case, since the initial gas composition in the storage chamber 1 is in a lower oxygen and high carbon dioxide state than the atmospheric composition, the operating energy of the storage gas supply means 4 necessary for exhibiting a certain vegetable storage performance, Consumable members can be reduced.

  As described above, the food storage according to the present invention can maintain the hermeticity of the storage room by changing the gas composition in the storage room by simultaneously operating the gas supply means and the atmospheric pressure adjusting means. It can be applied not only in equipment but also in industrial food storage. For example, it can be used to control the gas composition in the storage room in a commercial refrigerator, a refrigerated showcase, a cold car, an agricultural warehouse, a reefer container, a grain silo, and the like.

DESCRIPTION OF SYMBOLS 1 Storage room 2 Door 3 Door opening / closing detection means 4 Preservation gas supply means 5 Pressure control means (pressure reduction means)
6 Cooling means 7 Control means 8 Case 9 Case door 10 Pore closing means 11 Image recognition means 12 Food storage part 13 Spring structure 14 Slit 15 Slit 16 Second storage chamber 17 Blower means

Claims (7)

Supplying an airtight storage room, a door that opens and closes in order to put food in and out of the storage room, a door open / close detection means that detects opening and closing of the door, and a gas that has an effect of improving the storability of the food A storage gas supply means, a pressure adjustment means for adjusting the pressure in the storage chamber to 1 atmosphere or less, a control means for controlling the door opening / closing detection means, the storage gas supply means, and the pressure adjustment means, The control means detects the door closed by the door opening / closing detection means, operates the pressure adjusting means and the preservation gas supply means, and supplies the preservation gas to the storage chamber. 2. The cooling unit according to claim 1, further comprising a cooling unit that cools the storage chamber, wherein the control unit detects that the door is closed by the door opening / closing detection unit and then operates the cooling unit to cool the storage chamber. Food storage. Door opening / closing prediction means for predicting door opening / closing timing based on detection information of the door opening / closing detection means, and the control means operates the cooling means at a predetermined timing predicted by the door opening / closing prediction means to The food storage according to claim 1 or 2, wherein the storage chamber is cooled. The food storage according to any one of claims 1 to 3, wherein the storage gas supply means supplies a storage gas having a temperature lower than an indoor temperature of the storage chamber. The pressure adjusting means is a pressure reducing means for reducing the pressure in the storage chamber, and the control means detects the door closed by the door opening / closing detection means, and then operates the pressure reducing means to reduce the pressure in the storage chamber. The food storage according to any one of claims 1 to 4, wherein the storage gas is introduced by operating the storage gas supply means. There is a pore closing means for reducing the pore opening degree of the vegetable, and the control means operates the pore closing means to detect the opening degree of the vegetable after detecting that the door is closed by the door opening / closing detection means. The food storehouse according to any one of claims 1 to 5. The food storehouse according to any one of claims 1 to 6, further comprising moisture absorption means for absorbing water vapor evaporated and evaporated from the food in the storage chamber.

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