Method for storing rice flour, method for storing powdery food materials, and powdery food material storage device

Abstract

To provide a method capable of preventing rice flour, etc. from being oxidized without using a refrigerator.SOLUTION: A powdered food material storing apparatus 1 has: an outer shell body 2 having insulating properties and having open parts at least on one surface; a planar electrode 23 coated with an insulation material; a curtain-like or shop curtain-like opening / closing member 5; and a metal wall 6. Inside the outer shell body 2, three side surfaces in some area in a height direction are coated with the electrode; inside the outer shell body, the metal wall 6 is disposed in at least some of the other area in the height direction and on a top surface; the opening / closing member 5 is disposed at any of the open parts of the outer shell body 2; and a conductive sheet is attached inside a housing of the opening / closing member 5.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a method for storing rice flour. The present invention also relates to a method and an apparatus for storing rice flour and other powdery food ingredients.

Background Art

[0002] Rice flour is a powdery food ingredient obtained by milling rice. Rice flour has been used as a raw material for dumplings, mochi, senbei, etc. since ancient times. In recent years, it has also been used as a material for bread and confectionery instead of wheat flour. Rice flour does not contain gluten, which is a cause of wheat allergy, and can be eaten by people with wheat allergy.

[0003] On the other hand, since rice flour contains fat, it is likely to oxidize, and there is a problem that the taste deteriorates due to oxidation. Therefore, rice flour is often stored in the refrigerator. That is, when storing rice flour for a long time, it is often placed in the refrigerator.

[0004] In addition, as a refrigeration technology that has attracted attention in recent years, there is a method of creating an electrostatic field atmosphere inside the refrigerator. This technology utilizes the fact that by placing food ingredients in an electrostatic field atmosphere, it is possible to prevent the moisture in the food ingredients from freezing. By creating an electrostatic field atmosphere inside the refrigerator, food ingredients can be placed in a sub-zero environment without destroying the cells of the food ingredients, suppressing the growth of bacteria, and maintaining the freshness of the food ingredients.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] All conventional storage methods use a refrigerator and require large-scale equipment. The present invention proposes a method capable of preventing oxidation of rice flour etc. without using a refrigeration device. Another object of the present invention is to propose a device for storing new powdered food ingredients.

Means for Solving the Problems

[0007] An aspect for solving the above problems is a method for storing rice flour, characterized in that the rice flour is placed in a bag and / or a box and stored at normal temperature in an electrostatic field atmosphere.

[0008] Another aspect for solving the same problems is a method for storing rice flour, characterized in that the rice flour is put into a bag, and the bag is further put into a box and stored at normal temperature in an electrostatic field atmosphere.

[0009] According to the method for storing rice flour in each of the above aspects, oxidation of the rice flour can be suppressed without using a refrigeration device.

[0010] In each of the above aspects, it is desirable to place the rice flour in a space where at least two sides are surrounded by planar electrodes and an electrostatic field atmosphere is formed by supplying power to the electrodes.

[0011] According to this aspect, the rice flour can be placed in a strong electrostatic field atmosphere, and oxidation of the rice flour can be suppressed.

[0012] In each of the above aspects, it is desirable to place the rice flour in a space where electrodes covered on a part of the side surface are arranged, and wall members formed of a conductor are arranged on the same side surface, and an electrostatic field atmosphere is formed by supplying power to the electrodes.

[0013] According to this aspect, the rice flour can be placed in a strong electrostatic field atmosphere, and oxidation of the rice flour can be suppressed.

[0014] In each of the above aspects, it is desirable to place the rice flour in a space where at least one surface is a metal surface.

[0015] According to this aspect, rice flour can be placed in a strong electrostatic field atmosphere, and the oxidation of rice flour can be suppressed.

[0016] Another aspect for solving the same problem is a method for storing powdered food ingredients, characterized in that the powdered food ingredients are stored in a bag and / or a box at normal temperature in an electrostatic field atmosphere.

[0017] The powdered food ingredients are, for example, those referred to as cereal flours, and in addition to rice flour, include wheat flour, barley flour, buckwheat flour, rye flour and other cereal flours. The powdered food ingredients also include those made from corn such as corn flour and corn starch. Furthermore, flours made from beans, tubers, kudzu, arrowroot, etc. are also included in the powdered food ingredients.

[0018] An aspect related to a powdered food ingredient storage device includes an outer casing having insulation and an opening on at least one side, a planar electrode covered with an insulating material, a curtain-shaped or awn-shaped opening / closing member, and a metal wall. Inside the outer casing, three sides of a partial region in the height direction are covered with the electrode, and at least a part of another region in the height direction and the top surface inside the outer casing are provided with the metal wall. The opening / closing member is arranged at any opening of the outer casing, and a conductive sheet is mounted on the inner side of the housing of the opening / closing member.

[0019] According to the powdered food ingredient storage device of this aspect, the space where the powdered food ingredients are arranged can be made into a strong electrostatic field atmosphere. It also has a curtain-shaped or awn-shaped opening / closing member, and the powdered food ingredients can be taken in and out of the powdered food ingredient storage device by opening the opening / closing member.

Advantages of the Invention

[0020] According to the method for storing powdered food ingredients and the method for storing powdered food ingredients of the present invention, oxidation of rice flour and the like can be prevented without using a refrigeration device. Moreover, although the powdered food storage device of the present invention has a simple structure, it can suppress the oxidation of rice flour and the like, and can suppress the deterioration of powdered food over a long period of time.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0022] Hereinafter, embodiments of the present invention will be described. The powdered food storage device 1 of the present embodiment is a device for storing powdered food such as rice flour at normal temperature. The powdered food storage device 1 of the present embodiment is composed of an outer housing 2, an electrode member 3, an opening / closing member 5, and a metal wall 6, as shown in FIG. 3.

[0023] The outer housing 2 is a housing made of a material having insulating properties such as wood or resin. The front side of the outer housing 2 is open, and the other five sides are closed. That is, the outer housing 2 has a top wall 10, a bottom wall 11, a rear wall 12, and left and right side walls 15 and 16, and is a wooden box with an open front. The region surrounded by the top wall 10, the bottom wall 11, the rear wall 12, and the left and right side walls 15 and 16 becomes a storage space 18 for storing rice flour. The outer housing 2 has legs 17, and the bottom wall 11 is separated from the floor surface.

[0024] The electrode member 3 is a coated planar electrode. As shown in FIG. 4, the electrode member 3 is formed by sandwiching a net-shaped metal member (planar electrode) 23 between insulating resin sheets 20 and 21. The metal member (planar electrode) 23 may be a metal plate or a metal sheet. Also, the metal member (planar electrode) 23 may be a perforated metal plate such as a punching metal. In short, the planar electrode may be a conductor having a certain area. The width W of the electrode member 3 is approximately half of the height H of the accommodation space 18 of the outer body 2.

[0025] The opening / closing member 5 is a curtain or a shutter-like member, and as shown in FIG. 5(c), a metal sheet 7 is laminated on one surface of a base material 8 made of cloth or a sheet.

[0026] The metal wall 6 is made of aluminum, galvanized iron sheet, tinplate, etc.

[0027] In the powdery food storage device 1, the inner surface of the outer body 2 is lined with the metal wall 6. As shown in FIG. 3, the electrode member 3 is bent in a "U" shape and disposed inside the outer body 2. Specifically, the electrode member 3 is attached to the surface of the metal wall 6 on the back surface wall 12 and the left and right side walls 15 and 16 of the outer body 2. Note that the electrode member 3 is not in contact with the bottom surface wall 11 of the outer body 2. Since the width W of the electrode member 3 is approximately half of the height H of the accommodation space 18 of the outer body 2, the electrode member 3 is in a region approximately up to about half of the height H of the accommodation space 18 from the vicinity of the lower end of the accommodation space 18. Also, the electrode member 3 is disposed so as to surround three sides of a region approximately about half of the height H of the accommodation space 18.

[0028] In the present embodiment, the lower side approximately half of the back surface wall 12 and the left and right side walls 15 and 16 of the accommodation space 18 are covered with the electrode member 3. On the other hand, the upper side approximately half of the back surface wall 12 and the left and right side walls 15 and 16 of the accommodation space 18 and the top surface wall 10 have the metal wall 6 exposed. In this embodiment, electrodes are disposed on a part of the back surface wall 12 and the left and right side surface walls 15 and 16, and wall members formed of a metal wall (conductor) 6 are disposed on the same side surface.

[0029] The opening and closing member 5 is suspended from the top surface wall 10 of the outer body 2 and covers the opening portion on the front surface of the outer body 2. In this embodiment, one surface of the space where the rice flour is actually stored is covered by the opening and closing member 5, and this one surface is a metal surface formed by the metal sheet 7.

[0030] The powdery food storage device 1 is powered from a power supply device 30, and a high voltage is applied to a net-like metal member (planar electrode) 23. The power supply device 30 is composed of a variable resistor and a step-up transformer, and steps up 100 volts of commercial power by the step-up transformer. The output voltage is adjusted by the variable resistor.

[0031] In this embodiment, a voltage of about 500 volts to 1500 volts is applied to the net-like metal member (planar electrode) 23.

[0032] The rice flour is put into a bag 100 made of a resin such as vinyl as shown in FIG. 2, and is further packed in a cardboard box 101 and stored in the storage space 18 of the powdery food storage device 1. Specifically, a resin pallet 102 is installed on the bottom surface wall 11 of the outer body 2, and the cardboard box 101 is stacked thereon.

[0033] Inside the storage space 18, a high voltage is applied to the net-like metal member (planar electrode) 23, resulting in an electrostatic field atmosphere. Particularly in this embodiment, as shown in FIG. 5(b), three sides around the bag 100 and the cardboard box 101 containing the rice flour are covered by the net-like metal member (planar electrode) 23, and the bag 100 and the cardboard box 101 containing the rice flour are placed in a strong electrostatic field. Therefore, the cardboard box 101 and the bag 100 are charged, the surrounding of the rice flour becomes an ionic atmosphere, and the oxidation of the rice flour is suppressed. Particularly in this embodiment, as shown in FIGS. 2 and 5(a), since all the surfaces within the storage space 18 where the electrode member 3 does not exist are covered with the metal wall 6 or the metal sheet 7, static electricity is confined within the storage space 18, a high electric field strength is maintained, and the rice flour is less likely to oxidize. In addition, since the powdery food storage device 1 can store rice flour at room temperature, the power consumption is also low.

[0034] When taking the rice flour in and out of the powdery food storage device 1, turn off the power, and open one side of the storage space 18 by turning up the curtain-like or hanging-screen-like opening / closing member 5.

[0035] In the embodiment described above, the electrode member 3 is arranged in the lower region of three sides of the storage space 18, but the electrode member 3 may be arranged in the entire region in the height direction. Also, the electrode member 3 may be arranged on the top surface. In the embodiment described above, the electrode member 3 is arranged on three sides of the storage space 18, but the electrode member 3 may be arranged on only two sides. When the electrode member 3 is arranged on only two sides, it is desirable that the electrode member 3 is on the opposing surfaces.

[0036] When storing rice flour with the powdery food storage device 1 of this embodiment, the rice flour is less likely to oxidize and can maintain its quality over a long period. Also, powdery foods other than rice flour can be stored with the powdery food storage device 1 of this embodiment.

[0037] Next, the examples conducted to confirm the effects of the powdery food storage device 1 of this embodiment will be described.

Examples

[0038] 1 kg of rice flour was put into a plastic bag 100 and sealed. This bag 100 containing rice flour was put into a cardboard box 101. This cardboard box 101 was placed on a pallet 102 and installed in the storage space 18 of the powdery food storage device 1. A voltage of 1000 volts was applied to the metal member 23, and the rice flour was stored at room temperature for one month. As a control, one that was stored at room temperature for one month without using the powdery food storage device 1 was set up.

[0039] The acid value was adopted as an index for the quality change of rice flour. Then, the acid value of rice flour before the start of storage and after 1 month of storage was measured. The measurement of the acid value was carried out according to the method (colorimetric method) described in "Report of National Food Research Institute, No. 51, pp. 59 - 65, issued in November 1987" by Ohtsubo et al. Specifically, 1 g of rice flour was put into a stoppered test tube, 5 mL of toluene was added, and extraction was carried out in a constant temperature water bath at 30°C for 30 minutes. The extract was filtered using filter paper and transferred to a new stoppered test tube. 4 mL of chloroform was added, and further 2.5 mL of copper reagent (a mixed solution of 9 volumes of 1M triethanolamine, 1 volume of 1N acetic acid, and 10 volumes of 6.45% aqueous copper nitrate solution) was added, and it was strongly stirred. Centrifugation was carried out at 3000 rpm for 5 minutes. The upper blue aqueous phase was carefully removed with a pipette, and 3 mL was collected from the lower colorless chloroform layer into a test tube. 0.5 mL of an isobutanol solution of 0.1% sodium diethyldithiocarbamate was added, and it was strongly stirred. Then, the absorbance at 440 nm was measured with a spectrophotometer. Separately, calibration curves were prepared by performing the same operations using linoleic acid solutions of 10 μM, 50 μM, and 100 μM. Using this calibration curve, the amount of fatty acid in terms of linoleic acid for each sample was calculated. Incidentally, when the moisture content m (%) of the rice flour was measured in advance with a moisture meter, it was 11.1%.

[0040] Let the amount of fatty acid in terms of linoleic acid in 5 mL of toluene be X (μM), and the acid value was calculated by the following formula. Acid value [mg·KOH / 100g] = 561X / (100 - m)

[0041] As a result, first, the acid value of the rice flour before the start of storage was 42.0. And the acid value of the rice flour stored at room temperature for 1 month using the powdery foodstuff storage device 1 was 42.1, which was almost unchanged from before the start of storage, and the oxidation of fat was suppressed. On the other hand, the acid value of the rice flour stored at room temperature for 1 month without using the powdery foodstuff storage device 1 was 43.9, and the oxidation of fat had progressed. Thereby, it was shown that by storing rice flour using the powdery foodstuff storage device 1, even at room temperature, the quality change of rice flour can be suppressed in the long term.

Description of Symbols

[0042] 1 Powdered food storage device 2 Outer body 3 Electrode member 5 Opening / closing member 6 Metal wall 7 Metal sheet 20, 21 Resin sheets 23 Mesh-like metal member (planar electrode) 30 Power supply device 100 Bags 101 Cardboard box

Claims

Claim 1. A method for storing rice flour, comprising: storing the rice flour in a bag and / or a box at normal temperature in an electrostatic field atmosphere, wherein an electrode covered on a part of a side surface is arranged, and a wall member formed of a conductor is arranged on the same side surface, and the rice flour is placed in a space where an electrostatic field atmosphere is formed by supplying power to the electrode. A method for storing rice flour, characterized by the above. Claim 2. A method for storing rice flour, comprising: storing the rice flour in a bag and further storing the bag in a box at normal temperature in an electrostatic field atmosphere, wherein an electrode covered on a part of a side surface is arranged, and a wall member formed of a conductor is arranged on the same side surface, and the rice flour is placed in a space where an electrostatic field atmosphere is formed by supplying power to the electrode. A method for storing rice flour, characterized by the above. Claim 3 The method for storing rice flour according to claim 1 or 2, characterized in that at least two side surfaces are surrounded by planar electrodes, and the rice flour is placed in a space where an electrostatic field atmosphere is formed by supplying power to the electrodes. Claim 4 The method for storing rice flour according to any one of claims 1 to 3, characterized in that the rice flour is placed in a space where at least one surface is a metal surface. Claim 5. The method for storing rice flour according to any one of claims 1 to 4, characterized in that the electrode is coated with an insulating resin. Claim 6. The method for storing rice flour according to any one of claims 1 to 5, characterized in that the electrode is in a mesh shape.

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