JP2010166855A - Processing method for long storage of cereal, cereals processed to be storable for long, and processing apparatus for long storage of cereal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a processing method for long storage of cereals, to provide cereals processed to be storable for long, and to provide a processing apparatus for long storage of cereals. <P>SOLUTION: The processing method includes bringing steam plasma into contact with cereals for a short time. The cereals are various cereals such as rice, wheat, bean, corn, and millet, and may be cereals which are unskinned, skinned, crushed, ground, granulated or scraped. The steam plasma has a temperature of 40-600°C, and the time to bring the steam plasma into contact with the cereals is preferably for 0.1-30 s. The steam plasma is generated by either one kind selected from the group consisting of dielectric barrier electrical discharge, corona electrical discharge, high frequency electrical discharge, and microwave electrical discharge. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a method for enabling long-term storage of cereals, a grain subjected to processing for enabling long-term storage, and a processing device for enabling long-term storage of cereals.
It provides cereals that can be stored for a long period of time by sterilizing the surface of the cereals at low temperatures and in a short time under atmospheric pressure, avoiding its alteration, and can be stored for a long period of time without using radiation or chemicals. It provides cereals that can withstand.

"Necessity of a new sterilization method"
When food is transported or stored for a long period of time, it must be sterilized and sterilized in advance to kill bacteria, mold and insects. These organisms are unable to take the form of organisms due to destruction of cell membranes, protein immobilization, and DNA damage, resulting in death. (For example, the cell membrane of AIDS virus is so thin that it will die immediately if left in the air. On the other hand, the cold virus is covered with a strong membrane, so it is stable in the air and flies around the world, so it is avian influenza. (The virus is more dangerous for humans than the AIDS virus.)

  In Japan, where storage of cereals is indispensable, long-term storage of cereals is indispensable. Processed foods can withstand long-term storage, but canned cans still swell due to the propagation of germs during storage, and it is desirable from the viewpoint of food selectivity and safety if raw materials can be stored for a long time.

  As retort foods become widespread, whether or not they can be stored for a long time is the starting point of whether or not they are adopted as retort foods, and various sterilization and sterilization methods are applied.

  Sterilization means killing living cells of microorganisms, sterilization means killing non-pathogenic bacteria, pathogenic bacteria and bacterial spores, and disinfection means killing pathogenic microorganisms. Sterilization and sterilization are performed at high temperatures (protein denaturation and aggregation), high pressure (protein denaturation and aggregation), open flame (oxidation of organic substances), ultraviolet rays (DNA damage, generation of active oxygen), chemicals (protein denaturation and oxidation). Various methods have been reported for killing bacteria by other methods. However, since sterilization and sterilization are not clearly distinguished from each other in this field, sterilization and sterilization are hereinafter simply referred to as “sterilization”.

[Conventional sterilization method]
There are two types of sterilization methods: chemical sterilization method and physical sterilization method. The methods currently used are divided into physical method and chemical method.
Physical sterilization methods:
In addition to the incineration method and boiling method (20-30 minutes), bacterial spores do not die at 100 ° C, so use a steam sterilization method that repeats at 100 ° C for 30 minutes for 3 days, or microorganisms containing spores. Is treated with high pressure sterilization (2.5 atm, 120 ° C.) for 15-20 minutes or by dry heat sterilization at 150-160 ° C. for 30-60 minutes. Ultra high temperature short time sterilization, electric heating sterilization method is also used.
Physical sterilization by light sterilization irradiation:
For this purpose, an apparatus for sterilizing by irradiating with microwave, pulse electric field, ultraviolet ray, light pulse, radiation or the like has been developed and used. When gamma irradiation treatment is performed, gamma rays pass into the inside of the fruit in a very short time, killing all kinds of microorganisms most efficiently, and because they are processed by remote control, they are harmless to humans, but generally accepted in Japan I can't.
In particular, in ultraviolet irradiation sterilization, there are nucleic acids (DNA or RNA) that control genetic information in bacterial cells. When ultraviolet rays with large energy are absorbed into cells, the nuclear protein structure changes, and bacterial life is maintained. It is thought that the metabolism will be damaged and die. However, since some organisms have a DNA repair function, they must be irradiated at high power for a long time to be completely extinct. Some bacteria start to grow again when UV irradiation is stopped. Moreover, the sterilization of the shadowed part is insufficient.
In electron beam sterilization, microorganisms that have been exposed to several hundred million times more intense radiation in a short time compared to the natural radiation level are markedly inhibited in cell growth. In general, it is a difficult device. It is used for sterilization of medical equipment, pharmaceutical containers, food and beverage containers, caps, test equipment, clean room products, etc.

Chemical sterilization method:
Since chemicals are not effective unless they directly touch the organism to be sterilized, the scope of application is limited. Ozone sterilization and chlorine sterilization are used to sterilize tap water and wastewater. Pathogenic organisms whose cell membranes and cell walls have been destroyed are sterilized due to the effects of free residual chlorine and ozone on internal proteins and DNA. . Even using ionized acidic water, cells can be destroyed by oxidation. Heat sterilization with boiling water can heat and denature biological proteins to kill the organisms, but at the same time food materials are also heat-processed, food materials processed locally, canned, bottled And when stored as a vacuum pack, it is not suitable for sterilizing fresh food. Cryopreservation can be considered as a suppression of breeding rather than sterilization.

  Chemical sterilization inhibits the action of proteins or inhibits protein synthesis by invading microorganisms and chemically changing cells. However, care must be taken not to leave the disinfectant itself because it is a poisonous substance. Drugs used include alcohol, formaldehyde, phenol, cresol, bleached powder (quick lime absorbed chlorine), calcium hypochlorite, and benzalkonium chloride. Ethylene oxide is an insecticide that cannot be heated. Used for sterilization. Fumigation is one of the chemical sterilization methods. It is a method of exterminating pests by keeping the gas in a sealed space and holding it for a certain period of time. A fumigant, similar to a fumigant, is a mixture of a fire retardant, a heating agent, and an agrochemical. The active ingredient evaporates due to the heat generated by ignition and combustion. However, methyl bromide was banned due to environmental problems because of the risk of gas scattering and residual contamination to the environment. Bananas are fumigated with cyanide for insecticidal use and import permission is granted.

As an open patent technology regarding sterilization of cereals, cereal grains are pulverized after high-heat sterilization (Patent Document 1), and the grains germinated after immersing the grains in water are subjected to heat sterilization after drying. Sterile germinated cereal powder and method for producing the same (Patent Document 2), steaming after separation of the germ and skin in the production process of full-fat soybean, but heating is aimed at enzyme deactivation (Patent Document 3) There are food candy that is not suitable for food as it is and processed as a health food by treating it with ⁶⁰ Co or microwave heating (Patent Document 4). However, cereals and their physically processed products are altered as food materials. There is no report on how to store for a long time without letting go.

JP 2007-31694 A JP 2005-278557 A JP 2007-040551 A JP 2005-143480 A

  In order to sterilize heat-resistant bacteria using conventional sterilization methods, gamma irradiation and autoclave (autoclave sterilizer) have been used. Gamma rays are difficult to use for sterilization of general foods due to the circumstances in Japan, and the autoclave method has problems such as not only modifying foods but also making it difficult to process in large quantities. For this reason, it has been desired to develop a method for sterilization without modifying the food.

Until now, there is a limit to efficient sterilization without changing the characteristics of food materials, no matter what equipment is used, and there is no safe and non-food processing sterilization method that does not involve environmental pollution and food contamination. Development of a new sterilizer is desired.
An object of the present invention is to develop a sterilizing apparatus that does not require special management permission without degenerating cereals and to supply cereals that can be stored for a long time. As a result of intensive studies to solve the above problems, the present inventor decided to apply water vapor plasma that generates hydrogen and hydroxyl radicals that destroy the cell membrane.

That is, the present invention is a method for enabling long-term storage of cereals having the following constitution, a cereal subjected to long-term storage enabling processing, and a processing device for enabling long-term storage of cereals.
(1) A method for enabling long-term storage of cereals, wherein the cereals are contacted with water vapor plasma for a short time.
(2) The cereals are one or more selected from the group of skinned, moulted, crushed, comminuted, granulated, or ground (1) The method for enabling long-term storage of cereals according to (1).
(3) The cereal according to (1) or (2), wherein the cereal is one or more selected from the group consisting of rice, wheat, beans, and other cereals such as corn and millet Method for enabling long-term storage.
(4) The method for enabling long-term storage of cereals according to any one of (1) to (3), wherein the water vapor plasma is at a temperature of 40 to 600 ° C.
(5) The method for enabling long-term storage of cereals according to any one of (1) to (4), wherein the time for which the water vapor plasma is brought into contact with the cereal is 0.1 to 30 seconds.
(6) The water vapor plasma is generated by any one selected from the group consisting of dielectric barrier discharge, corona discharge, high frequency discharge or microwave discharge (1) to (5) The long-term preservation | save enabling method of the grain of any one of these.
(7) A grain that has been subjected to a long-term storage enabling process, obtained by the method according to any one of (1) to (6).
(8) An apparatus used in the method for enabling long-term storage of cereal according to any one of (1) to (6), wherein the water vapor plasma generator and the cereal are in contact with the water vapor plasma for a short time; A processing apparatus for enabling long-term storage of cereals, comprising:
(9) A flat plate or net plate 2 having a rough surface provided with an inclination, a vibrator 4 for imparting vibrations thereto, a hopper 1 disposed thereon, and the flat plate or net The apparatus for enabling long-term storage of cereals according to (8), comprising a water vapor plasma irradiation tube 6 for bringing the water vapor plasma into contact with the cereal 5 on the plate 2.
(10) A tilted rotary cylinder 7, a hopper 1 disposed on the rotary cylinder 7, and a water vapor plasma irradiation tube 6 for bringing water vapor plasma into contact with the grains 5 in the rotary cylinder 7 are provided. The processing apparatus which enables long-term storage of cereals according to (8).
(11) A cylindrical processing tower 10 having a cereal 5 and water vapor plasma inlet at the lower end and a derivation port for the mixture of cereal 5 and water vapor plasma at the upper end. A long-term storable processing device for cereals according to (8), comprising a cylindrical processing tower 10 provided.
(12) A doughnut-shaped short cylindrical body 11 provided horizontally at the lower end and provided with a cereal 5 and water vapor plasma inlet at the lower end and an outlet for the mixture of cereal 5 and water vapor plasma at the upper end. The mixture of the processed cereal 5 and the water vapor plasma is rotated in the donut-shaped short cylindrical body and brought into contact with each other, so that the contact-treated cereal 5 is taken out from the outlet at the upper end (8) The processing apparatus which enables long-term storage of the cereal described.

"Principles of steam plasma sterilization"
Plasma is a gas that is ionized positively and negatively. This was named by the American physical chemist Langmier for the state of the anode of a rare gas discharge tube. When a strong current is passed through the gas, or when the gas is heated to a high temperature using an arc or the like, some or all of the electrons will be free to fly away from the atoms. As a result, the atoms become charged positive ions. Such a state is a typical gas plasma.
When the rare gas argon is used as a gas source for generating plasma, molecules are decomposed to the atomic level and emit atomic emission lines. Helium and nitrogen are also used as gas sources and are called radio frequency (high frequency) inductive coupling that uses radio waves to induce and ionize gas molecules and microwave induced plasmas that use microwaves. Both devices excite gaseous molecules by ionizing them, and decompose organic substances introduced into them.

  A radical, translated as a free radical, is a molecular species with an unpaired electron, which is generally unstable and involved in the reaction of the species, changing a stable molecule into an unstable molecule. That is, it easily destroys cell membranes and changes the original structure of proteins and nucleic acids.

As a method for generating plasma, dielectric barrier discharge, corona discharge, high frequency discharge, microwave discharge, and the like are used depending on applications. Microwave (2450 MHz) induced plasma (Microwave Induced Plasma), which transforms helium gas into plasma with microwave electromagnetic waves, mixes with the surrounding atmosphere when ejected from the nozzle, and the temperature rapidly decreases, resulting in low-density reactive species. Form charged particles and low-temperature flow fields. Inductively coupled plasma, which converts nitrogen or argon gas into plasma with radio waves (27-50 MHz), decomposes and ionizes molecules in the plasma to emit light peculiar to atoms. Used in spectroscopic instruments together with plasma.
The gas between the electrodes can also be turned into plasma by arc discharge. Plasma is widely available, such as the ionosphere of the atmosphere and the corona of the sun. In an actual apparatus, only a part of the gas is in plasma, but the desired plasma can be obtained by adjusting the flow rate of the gas.

Sterilization using plasma:
Microwave plasma generator that can be used for the development of high concentration radicals by water discharge method for sterilization using hydrogen plasma, metal surface treatment, sterilization of medical and cooking utensils, ashing of IC wafers and printed circuit boards Development of microwave hydrogen plasma generator suitable for the sterilization of metal medical instruments and cooking utensils by the reduction of oxidized metal by reduction action, removal of organic contamination, metal sterilization, to change the characteristics of the lens Microwave treatment equipment, characterized by conjugating emitted particles that react with microorganisms and virus, methods and equipment to fragment and sterilize microorganisms and virus proteins without destroying microorganisms and virus nucleic acids, hydrogen peroxide and ozone Device for sterilization by keeping volume, device for sterilizing tubes with ozone, manufacturing method of anti-bacterial plastic container, hydrogen peroxide for food packaging material There are patent documents such as atmospheric pressure low temperature plasma disinfection method, ozone and hydrogen peroxide generated by discharge, detoxification of flue gas, water purification, wastewater treatment, pulp decolorization, medical instrument sterilization, etc. Since ozone oxidation occurs, it is not suitable for sterilization of foodstuffs.

  Other documents related to hydrogen plasma, sterilization, and food include sterilization of polyethylene terephthalate containers, food containers, systems that constantly supply plasma, systems that constantly sterilize by supplying hydrogen peroxide and ozone, medical equipment, heat resistance Although there are reports of sterilization of functional polymers, liquid sterilization by the discharge method, and hydrogen peroxide plasma for sterilization of the urinary tract, etc., it is not preferable for sterilization of foods because the oxidation reaction is applied.

  Regarding sterilization using hydroxyl radicals, development of small devices that generate sterilization by generating hydrogen peroxide, ozone, hydroxyl radicals, oxygen radicals, etc. during mixing of water and gas by applying high voltage between narrow electrodes, air, oxygen Escherichia coli was inactivated by pulse discharge plasma using nitrogen. In experiments using low-temperature atmospheric pressure plasma, it was found that oxygen atoms are important for E. coli inactivation. Low pressure radio frequency discharge plasma was used for sterilization of medical instruments. It was confirmed that oxidation is important for sterilizing oxygen radicals generated from oxygen and water. At that time, the presence of hydroxyl radicals was also measured. A small atmospheric pressure plasma generator was developed to sterilize Streptococcus mutans bacteria with the generated hydroxyl and oxygen radicals. Hydroxyl radicals were generated from water vapor in a pressurized sealed container, and medical instruments were sterilized using ozone plasma. Microorganisms could be sterilized in a short time with reactive species derived from oxygen and nitrogen generated by air plasma at atmospheric pressure. When sterilizing effect was examined using various plasmas at 55 degrees Celsius or lower, the lethality was high when 0.05 M water was used as the carrier gas of the plasma, and it was attributed to hydroxyl radicals. When oxygen was applied to the dry cleaning device and UV light was applied to the water vapor plasma, it could be quickly sterilized by hydroxyl radicals, peroxidation, oxygen atoms, etc.

  Therefore, in the present invention, cereals or granules or powders thereof are introduced into a water vapor plasma stream generating hydrogen and hydroxyl radicals having strong sterilization and sterilization power, and brought into contact with each other to instantly sterilize the surface. . Compared to the conventional method of sealing or semi-sealing heated steam, this treatment method is not sterilized by high heat, so heat is not applied to the inside of cereals and granules, so it adheres to the surface without modifying the internal structure. It can be sterilized by cell membrane destruction of various bacteria. Grains treated by this sterilization method can withstand long-term storage without contamination by external germs.

Application of water vapor plasma for sterilization of cereals:
Water vapor plasma is characterized by the use of water vapor as a gas and can be used anywhere. Since this water vapor plasma is chemically reactive despite its low temperature, it is used in the medical field for sterilization of living organisms and low heat-resistant materials and medical instruments, and is expected as a sterilization method that does not use chemicals. Yes. It has been observed that cell membranes are damaged when bacteria are irradiated with plasma and radicals with high reactivity for a short time. If time is taken, sterilization at a lower temperature is possible. In the living body, it generates radicals and is used for bactericidal action, information transmission, destruction of old proteins, etc., but it is generally short-lived and only occurs at the necessary site, but when waste products accumulate in the body, it generates active oxygen, Causes inflammatory diseases that result in tissue damage, necrosis, arrhythmia, and gastrointestinal ulcers.

As a result of the investigation, the following is described in various documents.
Water vapor plasma excited by radio waves is also used for sterilization of medical devices, and it can be sterilized at 55 degrees Celsius using the generated atomic oxygen and hydroxyl radicals.
When wool (keratin fiber) is treated with water vapor plasma, the surface becomes hydrophilic. The hydrophobic synthetic resin film was changed to hydrophilic by low-temperature steam plasma treatment.
When carbon black is treated with water vapor plasma at 100 degrees Celsius or less, hydroxyl groups are formed on the surface. A tire having a long life can be manufactured by further chemically treating the reactive hydroxyl group and adding the surface of carbon black to the rubber smoothly.
Also in the metal surface treatment, a method of bonding organic compounds by chemical reaction after introducing a hydroxyl group on the metal surface by plasma treatment has been devised.
When plasma is generated in a mixture of ethanol and water in order to improve the combustion efficiency of ethanol as a biofuel, hydrogen radicals purified from water react with ethanol at 161 degrees Celsius to produce hydrogen, and the hydrogen Increase fuel combustion efficiency.
When plasma is generated in the gas, SO ₂ reacts with hydroxyl radicals and is removed as sulfuric acid, and NOx can be removed as nitrogen. The generation of plasma from water is important in this reaction.
The role of water vapor plasma is important in decomposing carbon dioxide.
Hydrogen plasma generated from water in medium pressure ultrasonic discharge keeps the amount of hydrogen peroxide in the reaction solution constant. When performing a barrier discharge, the amount of ozone decreases, radicals containing hydrogen peroxide are generated, and bioactive substances increase when humid air is used.
Adding water to the oxygen plasma increases the amount of oxygen, reduces the activation energy of the ashing reaction, and the hydroxyl radical prevents semiconductor sodium addition.
A method for analyzing a plasma by exciting a small amount of water with microwaves has also been developed.
Designed simple plasma generation to generate hydrogen efficiently. The role of a small amount of water is also being studied in the induction plasma (ICP) using argon, and it is argued that water generates hydrogen and hydroxy radicals and affects the excitation temperature.

The water vapor plasma irradiation method is not a pressure-sealing method, but the surface of the cereal can be sterilized and sterilized by irradiating it under atmospheric pressure for a short time, and heat is not applied to the inside of the cereal, so the quality characteristics of the cereal are hardly changed. Heat-resistant bacteria can also be sterilized.
Bacteria, pests, etc. adhering to the cereal exist only on the surface of the cereal, so if the water vapor plasma is brought into contact with only the surface of the cereal, the cereal can be sterilized. Ideal for.

It is front sectional drawing which shows the apparatus of 1st Example of this invention. It is front sectional drawing which shows the apparatus of 2nd Example of this invention. It is a partial cross section front view which shows the apparatus of 3rd Example of this invention. It is front sectional drawing which shows the apparatus of 4th Example of this invention. It is front sectional drawing which shows the apparatus of 5th Example of this invention.

Next, the best mode for carrying out the present invention will be described with reference to the drawings.
In order to efficiently bring the water vapor plasma into contact with the surface of the cereal, it is necessary to directly irradiate the surface cells of the cereal. By simply irradiating a stationary object, only the upper surface irradiated with the water vapor plasma is sterilized, and the plasma is sterilized. Cannot kill bacteria attached to the lower surface that does not hit.
Furthermore, it is necessary to devise in order to sterilize continuously in the fluidized bed method. However, if the cereals on the upper surface of the mesh plate are irradiated with water vapor plasma from the lower surface of the mesh plate, the irradiation efficiency is derived from the linearity that is the characteristic of the plasma. Is bad. For this reason, in order to efficiently bring water vapor plasma into contact with the cereal placed on the upper surface, it is necessary to devise a method for rotating the cereal placed on the net plate surface.

Efficient water vapor plasma irradiation method for cereals:
Therefore, as shown in FIG. 1 (front cross-sectional view) as Example 1, a flat plate or net plate 2 having a rough surface is provided at an angle and inclined, and vibration by the vibrator 4 is applied. The cereal 5 rolls and flows downward from the hopper 1 disposed on the upper part of the flat plate or net plate, and the cereal 5 is irradiated and contacted with water vapor plasma emitted from the water vapor plasma irradiation tube 6.
Then, the cereal 5 'sterilized by water vapor plasma irradiation is obtained in the receiver 3 disposed below. Note that FIG. 2 (front sectional view) as Example 2 covers the apparatus of FIG. It is a thing.
In the above, the roughness of the flat plate may be adjusted according to the shape and specific gravity of the cereal to be plasma treated.
In the case of a net plate, select a shape that prevents the grain from falling through the mesh.

Further, as shown in FIG. 3 (partial cross-sectional front view) as the third embodiment, when the cereal 5 is caused to pass through the inclined rotating cylindrical body 7 while being rotated, it is disposed in the cylindrical body 7. It is desirable to efficiently irradiate the cereal 5 passing through the water vapor plasma released from the irradiation cylinder 6 while rotating.
Therefore, it is desirable to attach a fold 8 to the inner surface of the cylindrical body 7 in order to process a large amount of cereal 5 per unit length of the cylindrical body 7. In the same way as determining the inner diameter, considering the economic efficiency, it is determined by the shape, specific gravity and processing amount per unit time of the cereal to be plasma processed.
In addition, FIG. (A) is a partial cross-sectional front view, and FIG. (B) is an AA ′ cross-sectional view of FIG.

  Further, as shown in FIG. 4 (front sectional view) as Example 4, hot air is applied to the cylindrical processing tower 10 in which the lower part used for drying the cereal powder and the particulate matter 50 is conically suspended. If water vapor plasma from the water vapor plasma irradiation cylinder 6 is introduced instead of sterilization, not only drying but also sterilization can be performed. In the cylindrical processing tower 10, the cereal 5 and the water vapor plasma swirl and rise, and a mixture 12 of the cereal and the water vapor plasma treated with the water vapor plasma is derived from the upper part.

  Furthermore, as shown in FIG. 5 (front cross-sectional view) as Example 5, hot air or heated steam is passed through the doughnut-shaped short cylindrical body 11 placed horizontally to dry the powder or the particulate matter 50. Even when the apparatus is used, if the steam plasma from the steam plasma irradiation tube 6 is introduced instead of the heating steam generator, the powder and particles of cereal grains in the doughnut-shaped short cylinder 11 under the atmospheric pressure. The object 50 can be brought into rotational contact with the water vapor plasma. By doing so, water vapor plasma can be brought into contact with the entire surface of the cereal powder and the particulate object 50 with high efficiency, and sterilization at a relatively low temperature can be achieved.

The sterilization treatment of cereals by the water vapor plasma of the present invention described above causes other natural foods such as herbal medicines, herbs, vegetables, fruits, seafood, etc., to attach bacteria to the surface and cause rot, quality deterioration, etc. It can be suitably used for sterilizing natural animal and vegetable foods.
Further, not only natural foods but also processed foods can be applied to secondary contaminated foods that have a problem of causing spoilage or quality deterioration due to the adherence of germs on the surface after production.

1: Hopper 2: Flat plate or mesh plate 3: Receptor 4: Vibrator 5: Grain 5 ', 50: Grain treated with water vapor plasma 6: Water vapor plasma irradiation cylinder 7: Rotating cylindrical body tilted 8: Reed ( Folds)
9: Casing 10: Vertical cylindrical processing tower 11: Donut-shaped short cylindrical body 12: Mixture of cereal and steam plasma treated with steam plasma

Claims (12)

  A method for enabling long-term storage of cereals, characterized in that water vapor plasma is brought into contact with cereals for a short time.   That the cereal is one or more selected from the group of peeled, peeled, crushed, crushed, granulated, or ground The method for enabling long-term storage of cereals according to claim 1.   The cereal can be stored for a long period of time according to claim 1 or 2, wherein the cereal is one or more selected from the group consisting of rice, wheat, beans, and cereals such as corn and millet. Processing method.   The method for enabling long-term storage of cereals according to any one of claims 1 to 3, wherein the water vapor plasma has a temperature of 40 to 600C.   The method for enabling long-term storage of cereals according to any one of claims 1 to 4, wherein the time for which the steam plasma is brought into contact with the cereals is 0.1 to 30 seconds.   6. The water vapor plasma is generated by any one selected from the group consisting of dielectric barrier discharge, corona discharge, high frequency discharge or microwave discharge. The long-term preservation | save processing method of cereals as described in 1 ..   A cereal obtained by the method according to any one of claims 1 to 6, which has been subjected to a long-term storage enabling process.   It is an apparatus used for the long-term preservation | save enabling method of the cereal of any one of Claims 1-6, Comprising: It consists of a water vapor plasma generator and the apparatus which makes a cereal contact for short time to water vapor plasma. A long-term storage processing device for cereals.   A flat plate or net plate having a rough surface provided with an inclination, a vibrator for imparting vibrations thereto, a hopper disposed on the top, and water vapor on grains on the flat plate or net plate 9. The apparatus for enabling long-term storage of cereals according to claim 8, comprising a water vapor plasma irradiation tube for irradiating and contacting plasma.   An inclined rotating cylinder, a hopper disposed on the rotating cylinder, and a water vapor plasma irradiation tube for bringing water vapor plasma into contact with the grains in the rotating cylinder are provided. Item 9. A processing apparatus for enabling long-term storage of cereals according to item 8.   A cylindrical processing tower having a cereal and water vapor plasma inlet at the lower end and an outlet for a mixture of cereal and water vapor plasma at the upper end, the lower part of which is a conical shape, and a cylindrical shape formed vertically. The processing apparatus for enabling long-term storage of cereals according to claim 8, comprising a processing tower. A short doughnut-shaped cylindrical body having a cereal 5 and water vapor plasma inlet at its lower end and a cereal and water vapor plasma mixture outlet at its upper end, the cereal and water vapor introduced from its lower end 9. The cereal according to claim 8, wherein the mixture of plasma is rotated in the doughnut-shaped short cylinder and brought into contact with each other so that the contacted cereal is taken out from the outlet at the upper end. Processing equipment.