JP2009198097A - Refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refrigerator capable of efficiently increasing or maintaining a sweet component having large influence on an eating quality particularly in a nutrient of vegetables and fruits by saved energy. <P>SOLUTION: This refrigerator 1 includes a vegetable chamber 101 for storing the vegetables and fruits, and a temperature control unit 151 for controlling the temperature in the vegetable chamber 101. The temperature control unit 151 is constituted so as to control the temperature of the vegetable chamber 101 in response to a growing period of the vegetables and fruits stored in the vegetable chamber 101. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates generally to refrigerators, and more specifically to household refrigerators.

  Conventionally, a method has been proposed in which crops such as vegetables and fruits are stored at a low temperature to suppress metabolism such as respiration and enzyme activity of the crops, and prevent nutrients from being reduced in the crops during storage.

  However, the conventional method is merely a method for suppressing the decrease in nutrients in the crop, and is not a method for actively increasing the nutrient in the crop.

  Therefore, as a method of actively increasing nutrients in crops, for example, JP 2001-275606 (Patent Document 1) gives low temperature stress by storing potatoes under low temperature conditions, Methods have been proposed to increase potato ascorbic acid.

Japanese Patent Application Laid-Open No. 7-115952 (Patent Document 2) improves the taste by imparting stress such as drying and water addition to a living body of breathing food under a low temperature zone of 0 ° C. or lower. A method is described.
JP 2001-275606 A Japanese Patent Laid-Open No. 7-115952

  However, in the methods described in Japanese Patent Application Laid-Open No. 2001-275606 (Patent Document 1) and Japanese Patent Application Laid-Open No. 7-115952 (Patent Document 2), foods such as potatoes at a predetermined low temperature regardless of the time. Preserved kind. The temperature at which a fruit or vegetable feels low-temperature stress depends on the temperature environment to which the fruit or vegetable has been exposed. For example, when the temperature for storing foods is 0 ° C., foods grown under an outside air temperature of 27 ° C. in the summer are subject to the inventor's knowledge as the temperature subjected to low-temperature stress for increasing nutrients. According to this, it is stored at a temperature that is too low. On the other hand, in the case of foods grown under an outside air temperature of 0 ° C. in winter, storage at 0 ° C. makes it possible to feel low temperature as stress and increase nutrients. Thus, even when stored at a low temperature, according to the knowledge of the inventor, depending on the season, it has often been seen in the past cases that a low-temperature stress that is sufficient is applied.

  In order to increase nutrients in fruits and vegetables by low-temperature stress, it is possible to increase nutrients in fruits and vegetables grown in any environment by maintaining the storage temperature of fruits and vegetables at a very low temperature. However, on the other hand, increasing the nutrients by applying excessive low temperature stress to the fruits and vegetables regardless of the growing environment of the fruits and vegetables will add extra energy for the purpose of increasing the nutrients. In order to expand this function to refrigerators for consumer use, it was extremely problematic in terms of energy saving.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a refrigerator capable of efficiently increasing or maintaining sweetness components that have a great influence on the taste among fruits and vegetables.

  The refrigerator according to the present invention includes a vegetable room for containing fruits and vegetables, and a temperature control means for controlling the temperature in the vegetable room, and the temperature control means is in the growing season of the fruits and vegetables contained in the vegetable room. Accordingly, the temperature of the vegetable compartment is controlled.

  Fruits and vegetables are subjected to low temperature stress by being stored at low temperatures. In fruits and vegetables subjected to low temperature stress, a defense reaction is caused so that water in the fruits and vegetables is not frozen. As this defense reaction, for example, a proteolytic enzyme, a glycolytic enzyme, and a sugar synthesizing enzyme are expressed. Which enzyme is expressed as a protective reaction against low-temperature stress depends on the type and variety of fruits and vegetables. When proteolytic enzymes are expressed, proteins in fruits and vegetables are decomposed into amino acids, and the amount of amino acids in fruits and vegetables increases. As the amount of the water-soluble amino acid increases, the moisture in the fruits and vegetables becomes difficult to freeze due to the freezing point depression. In addition, when an invertase, a glycolytic enzyme, is expressed, sucrose, which is a disaccharide, is decomposed into fructose and glucose, which are monosaccharides, in fruits and vegetables. Fructose and glucose dissolve in the water in the fruits and vegetables, lowering the freezing point of the water in the fruits and vegetables and making the fruits and vegetables difficult to freeze. In this way, fruits and vegetables express proteolytic enzymes and saccharolytic enzymes as a defense reaction against low-temperature stress, increase the low molecular weight substances in the fruits and vegetables, and free themselves from freezing by lowering the freezing point of water in the fruits and vegetables. Prepare to protect.

  Thus, amino acids and saccharides increase in fruits and vegetables by the defense reaction of fruits and vegetables against low temperature stress. Amino acids include those that are known as umami components that cause umami and other sweetness components that cause sweetness. In addition, sugars make sweet taste. Therefore, the taste and sweetness of the fruits and vegetables can be increased by applying low temperature stress to the fruits and vegetables to cause a defense reaction of the fruits and vegetables against the low temperature.

  However, for example, fruits and vegetables cultivated in summer and grown at a relatively high temperature and fruits and vegetables cultivated in winter and grown at a relatively low temperature are sensitive to low temperature stress even at the same low temperature. Different. For example, even at a temperature of about 7 ° C., which is not generally regarded as a low temperature, fruits and vegetables grown at a relatively high temperature are perceived as low temperature stress, and umami and sweetness components are increased. On the other hand, fruits and vegetables grown at a relatively low temperature are felt as low-temperature stress only when placed at 0 ° C. to −1 ° C., which is generally felt as low temperature, and increase the taste and sweetness components.

  The inventors of the present application indicate that the amount of amino acids and saccharides increased in fruits and vegetables, in particular, the amount of amino acids and saccharides related to sweetening ingredients is stored at the temperature at which the fruits and vegetables are grown, not at the temperature at which the fruits and vegetables are stored. It was found that it depends on the difference from the temperature.

  In addition, the inventors of the present application indicate that the magnitude of the low temperature stress that the fruits and vegetables receive during storage increases as the difference between the temperature at which the fruits and vegetables are grown and the temperatures that are stored increases. We found that the critical point depends on the temperature at which the fruits and vegetables were grown.

  For example, fruits and vegetables grown at an outdoor temperature of 27 ° C. in summer are subjected to low temperature stress even when stored at a temperature of about 7 ° C. On the other hand, fruits and vegetables grown under an outside air temperature of 5 ° C. or less in winter are not subjected to low temperature stress at a temperature of about 7 ° C. Even if the types of fruits and vegetables are the same, if the temperature of the growing season is different, the critical temperatures at which the fruits and vegetables are subjected to low-temperature stress to cause a defense reaction are different.

  Thus, it was found that the critical temperature for whether or not to receive low-temperature stress varies depending on the temperature of the growing season. However, since the strength of low temperature stress is considered to be stronger as the storage temperature is lower, the amount of the enzyme expressed in the fruits and vegetables due to the low temperature stress is considered to increase as the temperature at which the fruits and vegetables are stored is lower.

  On the other hand, enzymes expressed in fruits and vegetables by low-temperature stress have an optimum temperature, and within the temperature range in the vegetable compartment of the refrigerator, the enzyme activity decreases when the temperature is low. If the enzyme activity is low, even if the enzyme is expressed by low-temperature stress, it becomes difficult for the enzyme to degrade proteins and polysaccharides, so that amino acids and saccharides are hardly increased in fruits and vegetables.

  Thus, the magnitude | size of the enzyme activity in fruits and vegetables is considered that the one where the temperature which preserve | saves fruits and vegetables is high becomes large within the temperature range of the vegetable compartment of a refrigerator.

  In other words, the amount of amino acids and saccharides in fruits and vegetables that increase by storing at low temperatures depends on the amount of proteolytic enzymes and saccharolytic enzymes determined by the size of low-temperature stress and the level of enzyme activity of these enzymes determined by temperature Depends on both.

  For example, fruits and vegetables grown under an ambient temperature of 5 ° C. in winter are not subjected to low temperature stress even when stored at 7 ° C., but are subjected to low temperature stress by being stored at −1 ° C., and enzymes are expressed. Amino acids and sugars in fruits and vegetables increase. On the other hand, fruits and vegetables grown under an outside air temperature of 27 ° C. in summer are sufficiently subjected to low-temperature stress even if stored at 7 ° C., and enzymes and sugars increase. When fruits and vegetables grown in summer are stored at a lower temperature of −1 ° C., even if the amount of the expressed enzyme increases, the enzyme activity is low, and proteins and polysaccharides are not decomposed, so that amino acids and saccharides are hardly increased.

  In addition, due to the metabolism of fruits and vegetables, sugars and amino acids produced in the fruits and vegetables are consumed by the fruits and vegetables themselves. For example, fruits and vegetables grown under an outside air temperature of 5 ° C. or less in winter are not subjected to low temperature stress at a temperature of about 7 ° C., but rather the storage temperature is higher than the growth temperature. Amino acids and sugars that are umami components and sweet components are consumed by metabolism.

  The total amount of amino acids and sugars in fruits and vegetables is the difference between the amount of amino acids and sugars produced as a defense reaction against low temperature stress and the amount of amino acids and sugars consumed by metabolism.

  The inventors have found that the amount of amino acids and sugars that increase in fruits and vegetables depends not on the temperature at which the fruits and vegetables are stored, but on the difference between the temperature at which the fruits and vegetables are grown and the temperature at which the fruits and vegetables are stored. The reason is considered as described above. The present invention has been made based on such inventor's knowledge.

  Therefore, in the present invention, the refrigerator includes a vegetable room for storing fruits and vegetables, and temperature control means for controlling the temperature in the vegetable room, and the temperature control means grows the fruits and vegetables stored in the vegetable room. By being configured to control the temperature of the vegetable compartment according to the season, it is possible to effectively increase the taste and sweetness components in the fruits and vegetables.

  In addition, by changing the storage temperature according to the growth temperature of fruits and vegetables, it is not necessary to lower the temperature of the vegetable room of the refrigerator unnecessarily, which is also effective for energy saving.

  By doing in this way, the refrigerator which can increase or maintain the sweet taste component which has a big influence on a taste especially among nutrients of fruits and vegetables efficiently by energy saving can be provided.

  The refrigerator according to the present invention includes date recognition means for recognizing the current date, and the temperature control means is configured to control the temperature of the vegetable room based on the date recognized by the date recognition means. Preferably it is.

  By doing in this way, according to the outdoor temperature of the season when the fruits and vegetables were grown, fruits and vegetables can be easily preserve | saved at the optimal temperature for increasing a umami component and a sweet taste component.

  The refrigerator according to the present invention includes an outside air temperature detecting means for detecting the outside air temperature, and the temperature control means is configured to control the temperature of the vegetable room based on the outside air temperature detected by the outside air temperature detecting means. It is preferable that

  By doing so, it is possible to easily store fruits and vegetables grown in a high temperature period and fruits and vegetables grown in a low temperature period at an optimum temperature for increasing the taste and sweetness components. it can.

  In the refrigerator according to the present invention, the temperature control means controls the temperature of the vegetable room according to the growing season of the fruits and vegetables accommodated in the vegetable room, and the outside air temperature detected by the outside air temperature detection means. Based on either the second temperature control in which the temperature control means controls the temperature of the vegetable room based on the growing season of the fruits and vegetables accommodated in the vegetable room or the outside air temperature detected by the outside air temperature detecting means. It is preferable to include a temperature control switching means for switching to a third temperature control that does not control the temperature.

  By doing in this way, according to the fruit and vegetables accommodated in the vegetable compartment, based on a user's judgment, fruit and vegetables can be preserve | saved at the optimal temperature for increasing a umami component and a sweet taste component.

  In the refrigerator according to the present invention, the temperature control means is preferably configured to be able to periodically change the temperature in the vegetable room within a predetermined temperature range.

  By doing in this way, since it can preserve | save about the various fruits and vegetables accommodated in a vegetable room, passing the critical temperature which receives low temperature stress, the amino acid and saccharides in various fruits and vegetables can be increased. .

  As described above, according to the present invention, it is possible to provide a refrigerator capable of efficiently increasing or maintaining a sweetening component that has a great influence on the taste among nutrients of fruits and vegetables.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view schematically showing an overall configuration of a refrigerator as one embodiment of the present invention.

  As shown in FIG. 1, the outer peripheral surface of the refrigerator 1 is a heat insulating box 100 configured by filling a heat insulating material between an outer box and an inner box, and heat insulation covering an opening on the front surface of the heat insulating box 100. It is formed by a door. The inside of the heat insulation box 100 is divided into a plurality of storage rooms in the vertical direction by a plurality of heat insulation partition plates. The storage room is, in order from the top, a refrigerated room 104 for storing food, an ice making room 103 for producing ice, a freezing room 102 for freezing food, and a vegetable room 101 for storing and storing fruits and vegetables. It is. The front opening of each of the refrigerator compartment 104, the ice making compartment 103, the freezer compartment 102, and the vegetable compartment 101 is opened or closed by the refrigerator compartment door 114, the ice making compartment door 113, the freezer compartment door 112, and the vegetable compartment door 111. Inside the heat insulation box 100, a refrigeration cycle unit, an electrical box 150, a cool air circuit 130, and the like are arranged on the back side of the storage chamber.

  The heat insulation box 100, the refrigerator compartment door 114, the ice making compartment door 113, the freezer compartment door 112, the vegetable compartment door 111, and the heat insulation partition plate are filled with a heat insulating material, and the temperature in the storage compartment is affected by the outside air. Is configured to not.

  The refrigeration cycle unit includes a compressor 121, an evaporator 122, and a condenser 125. The refrigeration cycle unit is a unit constituting a refrigeration cycle, and includes a compressor 121, an auxiliary radiator, a condenser 125, a decompressor (cold tube for cold gas, capillary tube for C), and an evaporator (main evaporation). 122) are connected in order by a refrigerant pipe (refrigerant pipe). A cycle in which the refrigerant that is the working medium of the refrigeration cycle flows in the order of the compressor 121, the condenser 125, and the evaporator 122 and returns to the compressor 121 is referred to as a cold gas cycle. The compressor 121 compresses the refrigerant at high temperature and high pressure. Since the compressor 121 generates operating heat, it is disposed in a machine room having a high degree of sealing and high heat insulation. The condenser 125 condenses and liquefies the refrigerant with defrost water. The condenser 125 also has a function of evaporating water (defrost water) generated when the evaporator 122 defrosts (defrosts). The evaporator 122 vaporizes the liquefied refrigerant (refrigerant liquid) that has become low temperature and low pressure through the condenser 125. The evaporator 122 evaporates (gasifies) the refrigerant liquid by taking the heat of the surrounding air in the refrigerator 1. Although various systems are used as the evaporator 122, a fin tube type heat exchanger is mentioned as an example. The air deprived of heat in the evaporator 122 becomes cool air of about −25 ° C.

  A fan 131 is disposed above the evaporator 122. The fan 131 sends air cooled in the vicinity of the evaporator 122, that is, cold air, into the cold air circuit 130.

  In the cold air circuit 130, a glass tube heater 123 and a drain pipe 124 are disposed below the evaporator 122, and an evaporating dish 126 is disposed below the condenser 125. The glass tube heater 123 melts frost on the evaporator 122. The defrost water is discharged to the evaporating dish 126 through the drain pipe 124.

  The air cooled to about −25 ° C. by the evaporator 122, that is, the cold air, is blown out into the cold air circuit 130 when the fan 131 is driven. The cool air blown into the cool air circuit 130 by the fan 131 flows through the cool air circuit 130 and flows into each storage chamber from the back side of each storage chamber.

  In the electrical box 150, a temperature control unit as temperature control means, a calendar part as date recognition means, a control part of the refrigerator 1, and the like are arranged. The control unit is a central part that controls the overall operation of the refrigerator 1, and organically controls the operation of each member such as the refrigeration cycle unit to control the operation of the refrigerator 1 in an integrated manner. The outside air thermistor 142 as an outside air temperature detecting means protrudes from the electrical box 150 toward the outside of the refrigerator 1. On the front surface of the heat insulation box 100, temperature control switching means for the user to switch temperature control and a temperature switching switch for the user to set the temperature in the vegetable compartment 101 are arranged. The temperature control switching means and the temperature switching switch may be arranged at different positions such as the side surface of the refrigerator 1.

  The flow of cold air in the refrigerator 1 will be described below. A heat insulating wall having a plurality of openings is formed on the back side of each storage chamber. In the refrigerator 1, a refrigeration cycle unit is disposed on the back side of the heat insulation wall, and cold air generated from the refrigeration cycle unit flows through the cold air circuit 130, passes through the opening of the heat insulation wall, and passes through the rear surface of the refrigerator 1. From the side toward the front side, the air is blown into each storage chamber in the direction indicated by the two-dot chain line arrow in the figure. Each storage room is cooled by such an indirect cooling method.

  The cold air flowing into each storage chamber passes through each storage chamber, freezes and refrigerates the food, and flows out from the front side of each storage chamber. The cold air flows from the front side of the refrigerator 1 toward the back side through the inside of the heat insulating partition plate and flows out in the vicinity of the evaporator 122 of the refrigeration cycle unit disposed behind the storage chamber.

  In the vicinity of the evaporator 122, the air is cooled again and blown out into the cool air circuit 130 by the fan 131. The cool air circuit 130 thus constitutes a cool air circulation path.

  For example, the cold air that has flowed into the vegetable compartment 101 from the cold air circuit 130 flows while cooling the inside of the vegetable compartment 101 along the outer peripheral surface of the internal container 115 to form the front surface of the heat insulating partition plate that forms the upper surface of the vegetable compartment 101. Then, it flows into the inside of the heat insulating partition plate, returns to the back side of the refrigerator 1, and flows into the back side cold air outflow passage.

  Inside the vegetable compartment 101, an internal container 115 is arranged so that the fruits and vegetables do not directly touch the cold air. The fruits and vegetables are accommodated in the inner container 115. A vegetable room thermistor 141 for detecting the temperature in the vegetable room 101 is attached in the vicinity of the internal container 115. In the vegetable compartment 101, a vegetable compartment damper 132 is disposed at the opening of the cold air circuit 130. The vegetable compartment damper 132 can open or close the opening of the cold air circuit 130 and switch whether the cold air is circulated in the vegetable compartment 101 or not. The vegetable compartment damper 132 is controlled to be opened and closed by a temperature control unit. The vegetable room damper 132 is interlocked with the temperature control in the vegetable room 101 and is opened when the inside of the vegetable room 101 needs to be cooled to introduce the cold air in the cold air circuit 130 into the vegetable room 101.

  FIG. 2 is a diagram schematically illustrating a vegetable room and a configuration for detecting and controlling the temperature of the vegetable room. The vegetable room is shown as seen from the side.

  As shown in FIG. 2, a vegetable room thermistor 141 is attached to the inner container 115 of the vegetable room 101. The vegetable room thermistor 141 is connected to the temperature control unit 151 in the electrical box 150. The temperature control unit 151 may be integrally disposed on the control board of the overall control unit of the refrigerator 1.

  FIG. 3 is a block diagram showing a configuration related to temperature control of the refrigerator as one embodiment of the present invention.

  As shown in FIG. 3, the vegetable room thermistor 141 detects the temperature in the vegetable room 101 and transmits a signal to the temperature control unit 151. Based on the signal received from the vegetable room thermistor 141, the temperature control unit 151 transmits a control signal to the vegetable room damper 132 so that the temperature in the vegetable room 101 is maintained at the target temperature, and the vegetable room damper 132. Controls the opening and closing of. When the vegetable compartment damper 132 is opened, cold air is introduced into the vegetable compartment 101 and the temperature in the vegetable compartment 101 is lowered. When the vegetable compartment damper 132 is closed, cold air is not introduced into the vegetable compartment 101, and the temperature in the vegetable compartment 101 is not lowered by the cold air.

  The calendar unit 152 sets the date and time when the refrigerator 1 is shipped from the factory, and continues to update the date and time thereafter. The initial setting date and time of the calendar unit 152 may be configured to set the current date and time when the user installs the refrigerator 1 in each home. The calendar unit 152 transmits a signal including information on the current date and time to the temperature control unit 151. Based on the signal received from the calendar unit 152, the temperature control unit 151 transmits a control signal to the vegetable room damper 132 so as to adjust the temperature in the vegetable room 101 according to the current date, and the vegetable room damper 132. Controls the opening and closing of.

  The outside air thermistor 142 detects the temperature of the outside air and transmits a signal to the temperature control unit 151. Based on the signal received from the outside air thermistor 142, the temperature control unit 151 sends a control signal to the vegetable compartment damper 132 so as to adjust the temperature in the vegetable compartment 101 according to the temperature of the outside air detected by the outside air thermistor 142. Send and control the opening and closing of the vegetable compartment damper 132.

  The temperature changeover switch 154 transmits a signal including the temperature in the vegetable compartment 101 set by the user to the temperature control unit 151. Based on the signal received from the temperature changeover switch 154, the temperature control unit 151 sends a control signal to the vegetable compartment damper 132 so as to keep the temperature in the vegetable compartment 101 at the set temperature set by the user through the temperature changeover switch 154. Send and control the opening and closing of the vegetable compartment damper 132.

  The temperature control switching means 153 is a first temperature control in which the user controls the temperature in the vegetable chamber 101 based on the current date, and a second temperature in which the user controls the temperature in the vegetable chamber 101 based on the outside air temperature. Switching means for switching between temperature control and third temperature control for controlling the temperature in the vegetable compartment 101 based on the temperature set by the user through the temperature switch 154.

  Here, the process of increasing the taste and sweetness components such as amino acids and sugars in fruits and vegetables by storing the fruits and vegetables in the vegetable compartment 101 of the refrigerator 1 will be described.

  FIG. 4 is a diagram schematically showing how proteins are decomposed and amino acids are synthesized in fruits and vegetables subjected to low temperature stress.

As shown in FIG. 4, the growth temperature T _{0 (℃)} Asparagus 200 as fruits or vegetables that have been grown in and stored at growth temperature T _{0 (℃)} [Delta] T than (℃) only cold storage temperature T (℃) The asparagus 200 is given a low-temperature stress S. At the growth temperature T ₀ (° C.), the protein 210 in the asparagus 200 is not decomposed into sugars or amino acids.

At a low storage temperature T (° C.), by applying a low temperature stress S, the fruits and vegetables express enzyme E as a defense reaction against freezing and decompose protein 210 into amino acids 220. Depending on the type of enzyme E, the polysaccharide may be decomposed to produce a monosaccharide or a saccharide may be synthesized. The amount of the enzyme E expressed in the asparagus 200 depends on the magnitude of the low temperature stress S, that is, the temperature difference ΔT (° C.) between the growth temperature T ₀ (° C.) and the storage temperature T (° C.). On the other hand, the degree of degradation of the protein 210 by the enzyme E depends on the magnitude of the enzyme activity, and the enzyme activity increases as the storage temperature T (° C.) approaches the optimum temperature of the enzyme.

Thus, in order for the protein 210 in the asparagus 200 to be decomposed and the amino acid 220 to increase, first, it is necessary to apply the low temperature stress S to the asparagus 200. If the low temperature stress S is not applied, the enzyme E is not expressed in the asparagus 200. Whether or not the low temperature stress S is given even at the same storage temperature T (° C.) depends on the growth temperature T ₀ (° C.) of the asparagus 200.

  For example, asparagus 200 grown at an outdoor temperature of 27 ° C. in summer is subjected to low temperature stress S even if stored at a temperature of about 7 ° C. On the other hand, asparagus 200 grown under an outside air temperature of 5 ° C. or lower in winter does not receive low-temperature stress S at a temperature of about 7 ° C. Even if the types of fruits and vegetables are the same asparagus, if the temperature of the growing season is different, the critical temperature at which the asparagus 200 is received as the low temperature stress S and the defense reaction is caused is different.

  On the other hand, asparagus 200 is metabolized, and sugars and amino acids 220 generated in asparagus 200 are consumed by asparagus 200 itself.

  The total amount of amino acids 220 and sugars in asparagus 200 depends on the amount of amino acids 220 and sugars produced as a defense reaction against low-temperature stress S, and the amount of amino acids 220 and sugars consumed by metabolism. Therefore, the enzyme E is expressed as much as possible by the low temperature stress S, and the enzyme E is activated to promote the increase of the umami component and the sweet component such as the amino acid 220 and sugar, and further the amino acid 220 and sugar by metabolism. By suppressing this decrease, the taste and sweetness of the asparagus 200 can be increased as a whole.

  Therefore, in the refrigerator 1, the temperature in the vegetable compartment 101 is controlled according to the growing season of the fruits and vegetables in the vegetable compartment 101. The temperature control in the vegetable compartment 101 will be described below. The temperature control in the vegetable compartment 101 is performed by the following first to third temperature controls. The first to third temperature control will be described with reference to FIG.

  The temperature in the vegetable compartment 101 is determined according to the temperature of the growth environment where the fruits and vegetables accommodated in the vegetable compartment 101 were grown as 1st temperature control.

  For example, in one year, the period from July 1 to October 31 is set in advance so that the summer period and the remaining period are the winter period. If the current date recognized by the calendar unit 152 is the summer period, the temperature control unit 151 controls the vegetable compartment damper 132 so that the temperature of the vegetable compartment 101 is 5 to 8 ° C. On the other hand, if the current date recognized by the calendar unit 152 is a winter period, the temperature of the vegetable compartment 101 is controlled to be 0 to -1 ° C. In the current distribution of fruits and vegetables, there are scenes where summer vegetables and winter vegetables are distributed throughout the year regardless of the season, but in this embodiment, it is assumed that the season is roughly divided into two seasons. In addition, depending on the region where the refrigerator 1 is actually installed, the distribution period of summer vegetables and winter vegetables may be slightly different, so the period setting needs to be configured to be adjustable by the user. .

  By doing in this way, even if the fruits and vegetables accommodated in the vegetable room 101 are grown in summer or grown in winter, it is possible to easily increase the umami component and the sweet component. Can be stored at the optimum temperature. In addition, by changing the storage temperature between the fruits and vegetables cultivated in summer and the fruits and vegetables cultivated in winter, the vegetable room 101 of the refrigerator 1 is not unnecessarily lowered, which is effective in saving energy.

  As described above, the refrigerator 1 includes the calendar unit 152 for recognizing the current date, and the temperature control unit 151 is configured to control the temperature of the vegetable compartment 101 based on the date recognized by the calendar unit 152. Has been.

  By doing in this way, according to the outdoor temperature of the season when the fruits and vegetables were grown, fruits and vegetables can be easily preserve | saved at the optimal temperature for increasing a umami component and a sweet taste component.

  The temperature in the vegetable compartment 101 is controlled based on the outside air temperature detected by the outside air thermistor 142 as the second temperature control. If outside temperature is 10 degreeC or more, the temperature in the vegetable compartment 101 will be hold | maintained at 5 degreeC or more and 8 degrees C or less, and if outside temperature is less than 10 degreeC, the temperature in vegetable compartment 101 will be -1 degreeC or more and 0 degreeC. The vegetable compartment damper 132 is controlled by the temperature control unit 151 so as to be held below.

  As described above, the refrigerator 1 includes the outside air thermistor 142 for detecting the outside air temperature, and the temperature control unit 151 is configured to control the temperature of the vegetable compartment 101 based on the outside air temperature detected by the outside air thermistor 142. Has been.

  By doing so, it is possible to easily store fruits and vegetables grown in a high temperature period and fruits and vegetables grown in a low temperature period at an optimum temperature for increasing the taste and sweetness components. it can.

  The temperature in the vegetable compartment 101 is adjusted as a third temperature control by the user operating the temperature changeover switch 154. In this case, the refrigerator 1 may include a notification unit, and may notify the user to change the set temperature based on the current date recognized by the calendar unit 152.

  In addition, the refrigerator 1 has a first temperature control in which the temperature control unit 151 controls the temperature of the vegetable room 101 according to the growing season of the fruits and vegetables accommodated in the vegetable room 101, and the outside air temperature detected by the outside air thermistor 142. Based on either the second temperature control in which the temperature control unit 151 controls the temperature of the vegetable compartment 101 based on the growing season of fruits and vegetables accommodated in the vegetable compartment 101 or the outside air temperature detected by the outside air thermistor 142. A temperature control switching unit 153 for switching between the third temperature control that does not control the temperature of the chamber 101 is provided.

  By doing in this way, according to a user's judgment according to the fruits and vegetables currently accommodated in the vegetable compartment 101, fruits and vegetables can be preserve | saved at the optimal temperature for increasing a savory ingredient and a sweet taste component. .

  Switching between the first temperature control, the second temperature control, and the third temperature control is performed by the user through the temperature control switching means 153.

  FIG. 5 is a diagram illustrating an example of a temperature change in a vegetable room whose temperature is controlled.

  As shown in FIG. 5, the temperature of the vegetable compartment 101 may be controlled so as to periodically change within a range from −1 ° C. to 8 ° C., for example. The temperature control unit 151 controls the vegetable compartment damper 132 so that the temperature of the vegetable compartment 101 detected by the vegetable compartment thermistor 141 changes periodically as shown in FIG.

  The critical temperature subjected to low temperature stress depends on the type of fruit and vegetables and the temperature at which the fruit and vegetables are grown. Therefore, when various fruits and vegetables are stored in the vegetable compartment 101, the temperature of the vegetable compartment 101 is periodically changed to change the critical temperature of the low temperature stress of all the fruits and vegetables accommodated in the vegetable compartment 101. Can pass through.

  Thus, in the refrigerator 1, the temperature control unit 151 is configured so that the temperature in the vegetable compartment 101 can be periodically changed within a predetermined temperature range.

  By doing in this way, since it can preserve | save about the various fruits and vegetables accommodated in the vegetable compartment 101, passing the critical temperature which receives low temperature stress, it can increase the amino acid and saccharides in various fruits and vegetables. it can.

  In addition, the period in which amino acids and sugars increase in fruits and vegetables stored at low temperatures varies slightly depending on the type of fruits and vegetables. This study has revealed that it is less than the immediate amount. Therefore, it is preferable that the period during which the fruits and vegetables are stored in the vegetable room 101 is within one week.

  As described above, the refrigerator 1 includes the vegetable room 101 for housing the fruits and vegetables and the temperature control unit 151 for controlling the temperature in the vegetable room 101, and the temperature control unit 151 is housed in the vegetable room 101. The temperature of the vegetable compartment 101 is controlled according to the growing season of the fruits and vegetables.

  In this embodiment, the refrigerator 1 includes a vegetable room 101 for containing fruits and vegetables and a temperature control unit 151 for controlling the temperature in the vegetable room 101, and the temperature control unit 151 is provided in the vegetable room 101. By being comprised so that the temperature of the vegetable compartment 101 may be controlled according to the growing season of the accommodated fruit and vegetables, the taste and sweetness component in fruit and vegetables can be increased effectively.

  In addition, by changing the storage temperature depending on the growth temperature of the fruits and vegetables, there is no need to unnecessarily lower the temperature of the vegetable compartment 101 of the refrigerator 1, which is effective for energy saving.

  By doing in this way, the refrigerator 1 which can increase or maintain the sweet taste component which has a big influence on a taste especially among nutrients of fruit and vegetables efficiently by energy saving can be provided.

  One effect of this invention is an increase in the amount of amino acids in fruits and vegetables. This effect was confirmed as follows.

  As fruits and vegetables, asparagus grown in winter, asparagus grown in summer, and cucumber grown in summer were measured for changes in the amount of amino acid in each case when stored at -1 ° C and stored at 7 ° C.

  Asparagus grown in winter, asparagus grown in summer, and 20 cucumbers grown in summer were each stored in a storage. In each case where the temperature in the storage was -1 ° C and 7 ° C, all 20 fruits and vegetables were mixed and the change in the amount of amino acids was measured.

  The amino acid was measured using high performance liquid chromatography (HPLC).

  As the amino acid analyzer, a high-speed amino acid analyzer of model number L-8800 manufactured by Hitachi, Ltd. was used. As the column, Hitachi Custom Ion Exchange Resin (φ4.6 mm × 60 mm) manufactured by Hitachi, Ltd. was used. As the mobile phase, a buffer solution of model number L-8500PF manufactured by Wako Pure Chemical Industries, Ltd. was used. As a reaction solution, a ninhydrin reagent manufactured by Wako Pure Chemical Industries, Ltd. was used.

  A sample used for measuring the amino acid amount was prepared as follows.

  First, various fruits and vegetables as samples were crushed with a homogenizer. Here, 10 W / V% sulfosalicylic acid was added as a deproteinizing agent. Thereafter, the mixture of the sample and sulfosalicylic acid was shaken well. As a result, the protein mixed in the sample reacted with sulfosalicylic acid and precipitated. This was filtered to prepare a sample solution from which the precipitate was removed. If protein remains in the sample, it may be decomposed into amino acids, so the pretreatment for removing the protein is performed at the stage of sample preparation.

  Next, the sample solution was diluted so as to obtain an appropriate concentration range measurable by this measurement method expected for each fruit and vegetable. This diluted solution was used as a test solution. Amino acids were analyzed by injecting this test solution into an automated amino acid analyzer utilizing the principle of liquid chromatography.

  For amino acid quantification, a standard sample with a known concentration is injected into an amino acid analyzer, its peak area is examined in advance, and the peak area of a sample with an unknown concentration is examined to determine how many times the peak area of the standard sample. The concentration was determined by calculating the sample concentration x magnification.

  In this measurement, alanine, glycine, proline, serine, and threonine, which are amino acids involved in the sweet taste component, were analyzed. Fruits and vegetables having an increased amount of sweetening components, ie, sweet-tasting amino acids, become sweeter and more delicious.

  FIG. 6 is a diagram showing changes in the amount of amino acids when asparagus grown in winter is stored at −1 ° C. (A) and when stored at 7 ° C. (B).

  As shown in FIG. 6A, when winter grown asparagus is stored at −1 ° C., the amount of amino acid is not increased on the third day from the start of storage, but the amount of amino acid is initial on the seventh day. More than that. On the 10th day, the amount of amino acid decreased compared to the 7th day, but more amino acid than the initial amount was detected. On day 14, it was less than the initial amino acid content.

  As shown in FIG. 6B, when the asparagus grown in winter was stored at 7 ° C., the amount of amino acids was greatly reduced on the third day from the start of storage. The amount of amino acid increased on day 7 than on day 3, but less than the initial amino acid amount. The amount of amino acid decreased further on the 10th and 14th days than on the 7th day.

  Thus, in asparagus cultivated in winter and cultivated in a cold growth environment, the amino acid of the sweetening component increased when stored at -1 ° C, but when stored at 7 ° C, In comparison, the amino acid content of the sweetening component did not increase.

  In addition, in asparagus cultivated in winter and cultivated in a cold growth environment, the amino acid amount became maximum on the seventh day from the start of storage when stored at -1 ° C.

  Depending on the type of fruit and vegetables, the time at which the amount of amino acid reaches the maximum amount is slightly different, but it is often the maximum after one week from the start of storage. By setting the period for storing fruits and vegetables in the refrigerator of the present invention to be within one week, the fruits and vegetables can be used for cooking in a state where the amino acid content of the sweetening component has increased most. In addition, since amino acids in fruits and vegetables increase within about one week from the start of storage, the effects of storing fruits and vegetables at a low temperature can be enjoyed in a normal life cycle such as bulk buying on weekends.

  The critical temperature at which fruits and vegetables are subjected to low-temperature stress is unique to individual fruits and vegetables, but for most fruits and vegetables cultivated in summer, storing at 5 to 8 ° C. became a low-temperature stress. Moreover, most of the fruits and vegetables cultivated in winter became low temperature stress when stored at -1 to 0 ° C. However, since the amount of enzyme expressed by low-temperature stress and the enzyme activity are unique to fruits and vegetables, the amount of amino acid may increase so much that it can be clearly felt as a taste. There was a rare case where it increased only to a certain extent.

  FIG. 7 is a diagram showing changes in the amount of amino acids when asparagus grown in summer is stored at −1 ° C. (A) and when stored at 7 ° C. (B).

  As shown to (A) of FIG. 7, when the asparagus of summer cultivation was preserve | saved at -1 degreeC, the amino acid amount increased from the initial stage on the 3rd day from the storage start. On the 7th day from the start of storage, the amino acid amount slightly decreased compared to the 3rd day, but increased compared to the initial day.

  As shown in FIG. 7 (B), when summer-grown asparagus was stored at 7 ° C., the amount of amino acids increased from the beginning on the third day from the start of storage. The amount of amino acid decreased on the 7th day compared to the 3rd day, but increased compared to the initial day.

  As shown in FIGS. 7A and 7B, on the third day, asparagus stored at 7 ° C. had a slightly higher amount of amino acid than asparagus stored at −1 ° C. On the seventh day, the amount of amino acids of asparagus stored at -1 ° C and that of asparagus stored at 7 ° C were almost the same.

  Thus, in asparagus cultivated in a warm growth environment in summer, the amino acid content of the sweet component increased regardless of whether it was stored at -1 ° C or 7 ° C.

  From the results shown in FIGS. 6 and 7, asparagus cultivated in a cold growth environment in winter is given low temperature stress when stored at −1 ° C., but low temperature stress is stored at 7 ° C. Is not considered to be given. On the other hand, it is considered that low temperature stress is given to asparagus cultivated in a warm growth environment in summer, whether stored at -1 ° C or stored at 7 ° C. From this, it is estimated that whether low temperature stress is given depends on the temperature difference (ΔT) between the growth environment and the storage environment. That is, since the cultivation temperature is low in the winter environment, ΔT is small even when stored at a low temperature of 7 ° C., and no low temperature stress is given, but when stored at a lower temperature of −1 ° C. It is estimated that low temperature stress is given. Further, since the cultivation temperature is high in the summer environment, ΔT increases even when stored at 7 ° C., and it is considered that low temperature stress is applied even at 7 ° C.

  Moreover, as shown in FIG. 7, in the experiment using asparagus grown in summer, the amount of amino acid was slightly higher at 7 ° C. than at −1 ° C. The difference ΔT between the growth temperature and the storage temperature is larger when stored at -1 ° C, and the strength of low-temperature stress is stronger when stored at -1 ° C, so the enzyme expression level is stored at -1 ° C. There are many who are done. On the other hand, the enzyme activity is higher at -7 ° C near the optimum temperature than -1 ° C. The amount of increase in amino acids (enzyme expression amount × enzyme activity) as a whole is considered to be higher when stored at −1 ° C. than when stored at 7 ° C.

  FIG. 8 is a diagram showing changes in the amount of amino acids when cultivated cucumbers are stored at −1 ° C. (A) and when stored at 7 ° C. (B).

  As shown in FIG. 8A, when summer-grown cucumbers are stored at -1 ° C., the amount of amino acids is about 1.4 times the initial amount on the third day from the start of storage, and about 1 on the eighth day. The amount of amino acids gradually increased to 8 times and about 2 times on the 14th day.

  As shown in FIG. 8B, when summer-grown cucumbers are stored at 7 ° C., the amount of amino acids is about 1.2 times the initial amount on the third day from the start of storage, and about 1. The amount of amino acids gradually increased to 5 times and about 1.6 times on the 14th day.

  Thus, it was found that cucumbers cultivated in a relatively warm growth environment in summer are subjected to low-temperature stress regardless of whether they are stored at -1 ° C or 7 ° C.

  From the above results, it was found that the temperature at which the amino acid of the sweet component in fruits and vegetables increases by storing at a low temperature depends on the temperature range of the growing environment of the fruits and vegetables. Therefore, by controlling the storage temperature of fruits and vegetables according to the growth temperature of fruits and vegetables, amino acids in fruits and vegetables, that is, umami components and sweet components can be increased.

  One effect of the present invention is an increase in the amount of sugar in fruits and vegetables. This effect was confirmed as follows.

  As fruits and vegetables, the time change of the sugar amount in each case when stored at -1 ° C and when stored at 7 ° C was measured for winter-grown cabbage, summer-grown carrot, and summer-grown watermelon.

  20 pieces each of winter-grown cabbage, summer-grown carrot, and summer-grown watermelon were stored in the storage. In each case where the temperature in the storage was -1 ° C and 7 ° C, all 20 fruits and vegetables were mixed and the change in the amount of amino acids was measured.

  The sugar amount was measured using a free sugar measurement kit (F kit: sold by JK International Co., Ltd., manufactured by Roche, Diagnostics) using an enzyme reaction.

  A sample for measuring free sugar was prepared by the following procedure. First, various fruits and vegetables as samples were crushed with a homogenizer. The crushed sample was filtered with gauze to remove only relatively large residues. The filtered sample solution was heated until just before boiling. By this operation, the enzyme contained in the sample was inactivated. The sample was centrifuged at 3000 rpm for about 1 minute to obtain a transparent supernatant. The supernatant was analyzed with F kit to quantify sucrose, glucose and fructose.

  The measurement principle of the F kit is shown below. In measuring glucose (glucose), the following reaction is used.

(1) Glucose + ATP → Glucose-6-phosphate + ADP (enzymatic reaction)
(2) Glucose-6-phosphate → Gluconic acid-6-phosphate + NADPH + H ⁺ (enzymatic reaction)
Since the amount of NADPH produced corresponds to the amount of glucose, quantification is performed by increasing the absorbance at 340 nm.

  For the measurement of fructose (fructose), the following reaction is used.

(3) Fructose + ATP → Fructose-6-phosphate + ADP (enzymatic reaction)
(4) Fructose-6-phosphate → glucose-6-phosphate (enzymatic reaction)
Glucose-6-phosphate is converted to gluconic acid-6-phosphate by the reaction (2), and the amount of NADPH produced at this time corresponds to the amount of fructose.

  In the measurement of sucrose (sucrose), the following reaction is used.

(5) Saccharose + H ₂ O → glucose + fructose After obtaining the glucose produced by hydrolyzing free glucose and sucrose as the total glucose amount in the reactions (1) and (2), the sucrose concentration And the total glucose amount.

  FIG. 9 is a diagram showing changes in the amount of sugar when winter-grown cabbage is stored at −1 ° C. (A) and when stored at 7 ° C. (B).

  As shown in FIG. 9 (A), when the cabbage grown in winter was stored at -1 ° C., the amount of sugar slightly increased from the beginning on the third day from the start of the storage. On the seventh day, the amount of sugar was almost the same as on the third day.

  As shown in FIG. 9B, when winter-grown cabbage was stored at 7 ° C., the amount of sugar slightly decreased from the initial stage on the third day after the start of storage. On the seventh day, the amount of sugar was almost the same as on the third day.

  Thus, in cabbage cultivated in winter and cultivated in a cold growth environment, the amount of sugar increased when stored at -1 ° C, but when stored at 7 ° C, compared to the initial level. As a result, the amount of sugar did not increase but gradually decreased.

  FIG. 10 is a diagram showing changes in the amount of sugar when watermelon grown in summer is stored at −1 ° C. (A) and when stored at 7 ° C. (B).

  As shown in FIG. 10 (A), when watermelon grown in summer was stored at −1 ° C., the amount of sugar increased on the third day after the start of storage, and further increased on the seventh day.

  As shown in FIG. 10 (B), when watermelon grown in summer was stored at 7 ° C., the amount of sugar increased on the third day after the start of storage, and further increased on the seventh day.

  Thus, in the watermelon cultivated in summer and cultivated in a warm growth environment, the amount of sugar increased after the start of storage whether stored at -1 ° C or stored at 7 ° C.

  FIG. 11 is a graph showing changes in the amount of sugar when summer-grown carrots are stored at −1 ° C. (A) and when stored at 7 ° C. (B).

  As shown in FIG. 11A, when summer-grown carrots were stored at −1 ° C., the amount of sugar increased on the third day after the start of storage, and further increased on the eighth day. On day 14, the amount of sugar was slightly reduced compared to day 8.

  As shown in FIG. 11B, when summer-grown carrots were stored at 7 ° C., the amount of sugar increased on the third day after the start of storage, and further increased on the eighth day. On the 14th day, the amount of sugar decreased compared to the 8th day.

  Thus, in carrots cultivated in summer and cultivated in a warm growth environment, the amount of sugar increased after the start of storage whether stored at -1 ° C or stored at 7 ° C. The amount of sugar reached a maximum on day 8.

  Depending on the type of fruits and vegetables, the time when the amount of sugar shows the maximum amount is slightly different, but in most cases it becomes the maximum one week after the start of storage. By setting the period for storing fruits and vegetables in the refrigerator of the present invention to be within one week, the fruits and vegetables can be used for cooking in a state where sugar is most increased. Moreover, since the sugar in fruits and vegetables increases within about one week from the start of storage, the effects of storing fruits and vegetables at a low temperature can be enjoyed in a normal life cycle such as bulk buying on weekends. Such a tendency that the amount of sugar increases within one week was also observed in other fruits and vegetables.

  From the above results, it was found that the temperature at which the amount of sugar of fruits and vegetables increases by storing at a low temperature depends on the temperature range of the growing environment of the fruits and vegetables. Therefore, by controlling the storage temperature of fruits and vegetables according to the growth temperature of fruits and vegetables, sugars in the fruits and vegetables, that is, sweetening components can be increased.

  The critical temperature at which the fruits and vegetables are subjected to low-temperature stress is a temperature unique to each of the fruits and vegetables, and depends on the type and growth temperature of the fruits and vegetables. For most fruits and vegetables cultivated in summer, storing at 5-8 ° C. became a low temperature stress. Moreover, most of the fruits and vegetables cultivated in winter became low temperature stress when stored at -1 to 0 ° C. However, since the amount of enzyme expressed by low-temperature stress and the enzyme activity are unique to fruits and vegetables, the amount of sugar may increase so much that it can be clearly felt as a taste. There was a rare case where it increased only to a certain extent.

  It should be considered that the embodiments and examples disclosed above are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above-described embodiments and examples but by the scope of claims, and includes all modifications and variations within the meaning and scope equivalent to the scope of claims.

1 is a cross-sectional view schematically showing an overall configuration of a refrigerator as one embodiment of the present invention. It is a figure which shows typically the structure which performs detection and control of the temperature of a vegetable compartment and a vegetable compartment. It is a block diagram which shows the structure relevant to the temperature control of a refrigerator as one embodiment of this invention. It is a figure which shows typically a mode that protein is decomposed | disassembled in the fruits and vegetables which received the low temperature stress, and an amino acid is synthesize | combined. It is a figure which shows the example of the temperature change of the vegetable room by which temperature control is carried out. It is a figure which shows the change of the amount of amino acids when the asparagus of winter cultivation is preserve | saved at -1 degreeC (A), and when preserve | saved at 7 degreeC (B). It is a figure which shows the change of the amount of amino acids when the asparagus of summer cultivation is preserve | saved at -1 degreeC (A), and when preserve | saved at 7 degreeC (B). It is a figure which shows the change of the amount of amino acids when the summer cucumber is preserve | saved at -1 degreeC (A), and when preserve | saved at 7 degreeC (B). It is a figure which shows the change of the amount of sugar when the cabbage of winter cultivation is preserve | saved at -1 degreeC (A), and when preserve | saved at 7 degreeC (B). It is a figure which shows the change of the amount of sugars when the watermelon of summer cultivation is preserve | saved at -1 degreeC (A), and when preserve | saved at 7 degreeC (B). It is a figure which shows the change of the amount of sugars when the carrot of summer cultivation is preserve | saved at -1 degreeC (A), and when preserve | saved at 7 degreeC (B).

Explanation of symbols

1: refrigerator, 101: vegetable room, 142: outside air thermistor, 151: temperature control unit, 152: calendar unit, 153: temperature control switching means, 200: asparagus.

Claims (5)

A vegetable room to house the fruits and vegetables,
Temperature control means for controlling the temperature in the vegetable compartment,
The said temperature control means is a refrigerator comprised so that the temperature of the said vegetable compartment may be controlled according to the growing season of the fruits and vegetables accommodated in the said vegetable compartment. A date recognition means for recognizing the current date,
The refrigerator according to claim 1, wherein the temperature control means is configured to control the temperature of the vegetable compartment based on the date recognized by the date recognition means. An outside air temperature detecting means for detecting the outside air temperature is provided,
The refrigerator according to claim 1 or 2, wherein the temperature control means is configured to control the temperature of the vegetable compartment based on the outside air temperature detected by the outside air temperature detection means.   The temperature based on the first temperature control in which the temperature control means controls the temperature of the vegetable room according to the growing season of the fruits and vegetables contained in the vegetable room, and the outside air temperature detected by the outside air temperature detecting means. The vegetable room based on either the second temperature control in which the control means controls the temperature of the vegetable room, the growing season of fruits and vegetables accommodated in the vegetable room, or the outside air temperature detected by the outside air temperature detecting means. The refrigerator according to any one of claims 1 to 3, further comprising temperature control switching means for switching to third temperature control that does not control the temperature of the first temperature control.   The said temperature control means is comprised so that it can change the temperature in the said vegetable compartment periodically within a predetermined temperature range, The structure of any one of Claim 1 to 4 Refrigerator.

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