WO2018181635A1 - Food production method, food, packaged food production method, and packaged food - Google Patents

Abstract

A food exhibiting the effects of superior pathogen removal and disinfection that do not adversely impact the original flavor of the food is provided by a food production method comprising a step of washing a target food with a jet stream of a liquid containing gas microbubbles with a diameter of less than 1 µm. A packaged food is also provided by following the washing step with a cutting step where the target food is cut in an aseptic condition and a packaging step where the target food is aseptically packaged.

Description

Method for producing food and food, and method for producing packaged food and packaged food

The present invention relates to a method for producing food and packaged food having a step of washing food using fine bubbles having a diameter of less than 1 μm, and food and packaged food produced by the production method.

Conventionally, when foods such as fruits and vegetables are provided, the foods are provided to consumers after a plurality of processes such as washing, sterilization, and freshness management. In recent years, many products have been circulated to save labor for cooking vegetables such as shredded cabbage. In the quality control of cut vegetables and the like, it is recognized that the reduction of the number of first germs is one of the important factors for reducing the microbial freshness along with the storage temperature. For this reason, conventionally, when food is produced, vegetables and the like are washed and sterilized using, for example, a food additive having a bactericidal action such as hypochlorous acid, slightly acidic electrolyzed water, and peracetic acid preparation as a bactericidal agent. Since these chemical substances are not allowed to remain in the final product, a cleaning process using a large amount of cleaning water is required.

Thus, sterilization and sterilization of fruits and vegetables such as vegetables with hypochlorous acid are generally performed. For example, according to the sterilization treatment with hypochlorous acid, the cut vegetables are put into an aqueous solution of 200 ppm hypochlorous acid, soaked for about 1 to 30 minutes, and then washed with sterile chiller water until no chlorine is detected. Therefore, it is said that the number of bacteria can be reduced to about 1/100. As hypochlorous acid used for sterilization treatment, hypochlorous acid water, sodium hypochlorite and the like are generally used. In addition, even if it is a case where it only calls "sterilization" through this specification, the meaning of "sanitization" which excludes a microbe and microorganisms physically shall be included.

However, an improved method has also been proposed for the cleaning method using hypochlorous acid. For example, as a method for producing shredded cabbage using an aqueous solution of a disinfectant such as sodium hypochlorite, a technique of performing shredding treatment while pouring fresh water into the cut portion of the cabbage after the sterilization treatment process and then exposing to water for a certain time or more (For example, refer to Patent Document 1 below). According to the technique, it is said that it can be sufficiently sterilized to greatly reduce the taste of cabbage.

On the other hand, in recent years, a technique using a liquid containing fine bubbles has attracted attention. For example, fine bubbles having a diameter of 100 μm or less are sometimes referred to as “fine bubbles (registered trademark)”, and their use in various fields is being studied. Among the fine bubbles, those having a diameter of less than 1 μm are called “Ultra Fine Bubble (registered trademark)” in that they exhibit various effects such as growth promotion effect of animals and plants, water quality improvement effect, sterilization effect, and bactericidal effect. Attention has been paid.

As a method for washing food using such fine bubbles, a method for washing food using chlorine bubbled water containing fine bubbles and sodium hypochlorite concentration of 20 to 80 ppm is disclosed. (For example, refer to Patent Document 2 below). The purpose of this technique is to exhibit sterilization and sterilization action by dissolving sodium hypochlorite in the fine bubble water because it has little sterilization and sterilization effect.

International Publication WO2012 / 073840 JP 2017-38528 A

However, in recent years, it has been confirmed that sterilization treatment with hypochlorous acid has a limit in its sterilization effect. This is presumed to be because hypochlorous acid comes into contact with organic substances and reacts with chlorine to reduce free chlorine, resulting in a drastic decrease in bactericidal activity. Moreover, cut vegetables sterilized with hypochlorous acid often feel a chlorine odor when put into the mouth even after being washed with water, and the original taste of the vegetables is also impaired. In particular, in the case of sliced green onions used for condiments and cut onions for salads, when sterilized with hypochlorous acid, the original flavor of freshly cooked vegetables is lost and becomes nearly tasteless.

For example, when using onions used for condiments for noodles such as buckwheat noodles or onions used for salads and sautes as cut vegetables, after removing inedible parts, cutting processing is performed and then hypocite is used as a disinfectant. Chloric acid is put into an aqueous solution of about 200 ppm to sterilize. After these are sterilized, the remaining hypochlorous acid is washed with cold water (chiller water), and then sealed in a plastic bag and packaged by sealing the bag mouth. However, in a vegetable having a layered structure such as a bar onion or onion, chlorine that has entered from the cut surface tends to remain between the layers, and a chlorine odor tends to remain.

Moreover, when a barley leek etc. reacts with a hypochlorous acid aqueous solution and the sticky part inside a leek, a unique flavor will fall remarkably. Furthermore, after sterilizing the cut vegetables with hypochlorous acid, a large amount of sterile water is used to remove the chlorine odor. This process results in further loss of flavor components of the leeks.

On the other hand, the development of alternative technology for hypochlorous acid is required in order to improve the working environment, adverse effects during eating and the original taste of food. Therefore, a technique for introducing slightly acidic electrolyzed water having a bactericidal effect even if the chlorine concentration when using hypochlorous acid is reduced to several tens of ppm is increasing. However, even in such a technique, chlorine is deactivated by the coexisting organic matter, and therefore it is necessary to replenish the slightly acidic electrolyzed water by pouring in order to exert the bactericidal effect. Also, since chlorine is not allowed to remain in the product, cleaning after sterilization is essential.

In this respect, technology using fine bubbles is also attracting attention as a candidate. However, the sterilizing effect is weak enough to immerse or stir food such as fruits and vegetables in a liquid containing fine bubbles, and there is still room for improvement in order to replace hypochlorous acid. As described above, development is required for a food cleaning technique that substitutes for hypochlorous acid using fine bubbles, but there has not yet been achieved a sufficient effect.

In order to solve the above-mentioned problems, the present invention provides a sanitary production method of food and packaged food that is excellent in sterilization and bactericidal action without losing the original taste of food, and the food and packaging produced by the production method. The purpose is to provide finished food.

<1> A method for producing food, comprising a step of washing the target food with a jet of liquid containing fine bubbles having a diameter of less than 1 μm.
<2> The method for producing food according to <1>, wherein the fine bubbles have a diameter of 10 nm to 500 nm.
<3> method of manufacturing a food according to the said concentration of said micro-bubbles in the liquid is 10 ⁶ cells / ml or more <1> or <2>.
<4> The <1> for cleaning the target food with a liquid containing the fine bubbles discharged at a rate of 0.05% by volume or more per second and a pressure of 0.01 MPa or more with respect to the washing tank volume per discharge port. The method for producing a food according to any one of to <3>.
<5> The method for producing food according to any one of <1> to <4>, wherein the cleaning time by the liquid jet is 2 seconds to 30 minutes.
<6> The method for producing a food according to any one of <1> to <5>, wherein the target food is a cut food.
<7> Food washed by a washing method in a step of washing with a jet of liquid containing fine bubbles having a diameter of less than 1 μm.
<8> The food according to <7>, wherein the fine bubbles have a diameter of 10 nm to 500 nm.
<9> food according to the said concentration of microbubbles is 10 ⁶ cells / ml or more in the liquid <7> or the <8>.
<10> The above items <7> to <9, which are cleaned with a liquid containing fine bubbles discharged at a rate of 0.05% by volume or more per second and a pressure of 0.01 MPa or more with respect to the volume of the cleaning tank per discharge port. > The food according to any one of
<11> The food according to any one of <7> to <10>, wherein the cleaning time by the liquid jet is 2 seconds to 30 minutes.
<12> The food according to any one of <7> to <11>, which is a cut food.
<13> A washing step of washing the target food with a jet of liquid containing fine bubbles having a diameter of less than 1 μm;
A cutting step of cutting the target food washed by the washing step in a sterile state;
A packaging step of packaging the target food cut in the cutting step in a sterile state;
A method for producing prepackaged food.
<14> In the cleaning step, the target food is cleaned with a liquid containing the fine bubbles discharged at a rate of 0.05% by volume or more and a pressure of 0.01 MPa or more per second with respect to the volume of the cleaning tank per discharge port. The method for producing packaged food according to <13>.
<15> The method for producing a packaged food according to <13> or <14>, wherein the fine bubbles have a diameter of 10 nm to 500 nm.
<16> method for manufacturing the wrapped food according to any one of the above in a liquid the concentration of microbubbles is 10 ⁶ cells / ml or more <13> - <15>.
<17> The method for producing packaged food according to any one of <13> to <16>, wherein the washing time in the washing step is 2 seconds to 30 minutes.
<18> The method for producing packaged food according to any one of <13> to <17>, wherein the target food is a vegetable having a layered structure.
<19> Packaged food that has been washed and packaged in a sterile state after being washed by a jet of liquid containing fine bubbles having a diameter of less than 1 μm.
<20> Cleaning with a jet of a liquid containing the fine bubbles and a liquid containing the fine bubbles discharged at a rate of 0.05% by volume or more per second and a pressure of 0.01 MPa or more with respect to the volume of the washing tank per discharge port. The packaged food according to <19>.
<21> The packaged food according to <19> or <20>, wherein the fine bubbles have a diameter of 10 nm to 500 nm.
<22> the wrapped food according to any one of the said concentration of microbubbles is 10 ⁶ cells / ml or more in the liquid <19> - <21>.
<23> The packaged food according to any one of <19> to <22>, wherein the cleaning time by the liquid jet is 2 seconds to 30 minutes.
<24> The packaged food according to any one of <19> to <23>, in which vegetables having a layered structure are packaged.

ADVANTAGE OF THE INVENTION According to this invention, the sanitary manufacturing method of the food and the packaged food which were excellent in microbe elimination and bactericidal action without impairing the original taste of food, and the food manufactured by the said manufacturing method, and the packaged food are provided. Can do.

Hereinafter, the contents of the present invention will be described in detail using embodiments. However, the following embodiments are examples, and the present invention is not limited to these embodiments.

The food production method and packaged food production method of the present embodiment (hereinafter sometimes collectively referred to as “production method of the present embodiment”) include the target food containing fine bubbles having a diameter of less than 1 μm. It includes a step of cleaning with a jet of liquid (hereinafter sometimes simply referred to as “cleaning step”).

Furthermore, in the method for producing packaged food according to the present embodiment, in addition to the cleaning process, a cutting process for cutting the target food cleaned by the cleaning process in an aseptic state, and the target food cut in the cutting process is aseptic The packaging process of packaging in a state is continuously performed. Here, “continuously performing” each process means that the cleaning process, the cutting process, and the packaging process are continued without a sterilization process using hypochlorous acid or the like between the processes. Means to be done. However, each process may be performed in a state of coexisting with the liquid used in the cleaning process. In addition, the manufacturing method of the packaged food of this embodiment is positioned as one aspect | mode of the manufacturing method of the food of this embodiment.

Hereinafter, fine bubbles having a diameter of less than 1 μm may be appropriately referred to as “UFB”. The production method of the present embodiment is a hygienic production method, which can clean the target food without deteriorating the original taste of the food, and can be cleaned by the cleaning without using a disinfectant such as hypochlorous acid. The food can be sterilized.
Furthermore, according to the method for producing packaged food of the present embodiment, after the target food is washed (sterilized) and cut, the packaged food is produced without losing the original flavor and umami of the food. Can do.
For this reason, the food manufactured by the manufacturing method of the present embodiment, that is, the food cleaned by the cleaning method in the step of cleaning with a jet of liquid containing fine bubbles having a diameter of less than 1 μm is a hypochlorous acid-treated food. It is possible to show a sterilization rate equal to or higher than. Further, since hypochlorous acid is not used, the food produced by the production method of the present embodiment does not have a chlorine odor, and the flavor is not impaired by the reaction with hypochlorous acid. It has flavor and umami. In addition, as mentioned above, even when simply referred to as “sterilization” throughout this specification, the meaning of “sanitization” that physically excludes bacteria and microorganisms is also included. Moreover, in the manufacturing method of this embodiment, it is necessary that the apparatus and apparatus which contact object food are fully cleaned, and do not become a pollution source.

According to the manufacturing method of the present embodiment, the bactericidal effect is higher than when the target food is simply immersed in a liquid containing UFB. Although the mechanism by which the cleaning process in the present embodiment can exert a high sterilizing effect on the target food is not clarified, the number of collisions between the liquid and the target food is increased by using a liquid containing UFB as a jet. It is speculated that one reason is that the number of bacteria remaining in the target food can be reduced as compared with the case of simply immersing and shaking. Furthermore, according to the manufacturing method of the present embodiment, the bactericidal effect can be enhanced even when compared to the case where microbubbles having a diameter of about 1 μm to 100 μm are used instead of UFB.

Moreover, the manufacturing method of this embodiment may include processes other than a washing process. For example, in the case of the method for producing packaged food according to the present embodiment, a cutting process and a packaging process are included in addition to a cleaning process, but other processes are appropriately included before the cleaning process and after the packaging process. May be.
As other processes that can be included in the manufacturing method of the present embodiment, for example, a preparation process for preparing a target food by performing a pre-cleaning treatment or the like can be cited. Moreover, it is preferable that the manufacturing method of this embodiment is performed hypochlorous acid free throughout all processes. In addition, for example, in the case of the packaged food manufacturing method of the present embodiment, when the target food is transported between the cleaning process and the cutting process, and between the cutting process and the packaging process, also in the transport process. Aseptic conditions are maintained. In addition, the conveyance using a water flow is also possible between each process (between apparatuses used for each process). It is preferable in terms of safety to use aseptic water, particularly UFB-containing aseptic water, when transporting using the water flow.
Hereinafter, in the manufacturing method of the present embodiment, a cleaning process which is an essential process will be described first. Next, each process will be described focusing on the cutting process and the packaging process.

(Washing process)
The “cleaning step” in the present embodiment is a step of cleaning the target food with a jet of liquid containing fine bubbles having a diameter of less than 1 μm. The washing process can use the target food prepared through a preparatory process such as pre-washing to remove mud or dust adhering to the above or removing a non-eating portion. In addition, the manufacturing method of the present embodiment is capable of cleaning and sterilizing the target food without using a sterilizing agent such as hypochlorous acid in the cleaning process. It is not necessary to perform a process. For this reason, it is not necessary to use a large amount of chiller water or the like, which is excellent from the viewpoint of cost and resources. However, it is preferable that the step carried out after the washing step is carried out under aseptic conditions in order to prevent bacteria and microorganisms from adhering to the food after washing. The aseptic condition is preferably ensured by sterilizing equipment and facilities on the assumption that the products that enter the consumer's mouth and their raw materials do not come into contact with chemical substances such as hypochlorous acid.

-Target food-
The “target food” in the present embodiment is not particularly limited as long as it can be washed with a liquid. For example, in addition to fruits and vegetables such as vegetables and fruits, fresh foods such as seafood and meat, processed foods such as tofu and konjac In particular, a cooked product that is not heat-sterilized is a suitable target. Furthermore, fruits and vegetables are suitable as the target food, and the production method of the present embodiment can be suitably used particularly for vegetables having a layered structure such as stick onions and onions. Also, the state of the food is not particularly limited. For example, the food may be cut (cut) or may be food before being cut. For this reason, when providing cut foods such as shredded cabbage and fish fillets, according to the type of the target food, the cutting process is performed before the cleaning process, and the cut target food is washed with UFB. Alternatively, the cutting process may be performed after the cleaning process, and the target food may be cut after the cleaning. In addition, in the manufacturing method of the packaged food of this embodiment which is an aspect of the manufacturing method of this embodiment, the target food cleaned by the cleaning process is cut in an aseptic state in the cutting process.

-Liquid containing fine bubbles-
The “fine bubbles” in the present embodiment are fine bubbles having a diameter of less than 1 μm, and nano-sized fine bubbles called “ultra fine bubbles” can be preferably used. When the diameter of the fine bubbles is 1 μm or more, the rising speed is higher in the liquid than the fine bubbles having a diameter of less than 1 μm, and the surface tends to float and disappear, so that a sufficient cleaning effect cannot be obtained. The rising speed of the fine bubbles at this time follows the following formula (Stokes formula).
Ascent rate U = ρgd ² / 18μ
d: Diameter of spherical bubbles, g: acceleration of gravity, ρ: liquid density, μ: liquid viscosity The diameter of the fine particles in the present embodiment is not particularly limited as long as it is less than 1 μm, but the viewpoint of the vegetable surface structure Therefore, the thickness is preferably 10 nm to 500 nm. The presence of UFB in the liquid can be confirmed, for example, by using laser light scattering.

The method for measuring the diameter of the fine bubbles is not particularly limited. For example, dynamic light scattering (DLS), particle tracking analysis, laser analysis, resonance mass measurement (RMM), etc. These known methods can be used as appropriate. The average diameter of the fine bubbles measured by these known methods can be regarded as the diameter of the fine bubbles.

Although not particularly limited in the concentration of micro-bubbles (UFB) in is in the liquid used in the washing step, from the viewpoint of cleaning and sterilizing efficiency, preferably 10 ⁶ cells / ml or more, 10 ⁷ / More preferably, it is more than ml, and more preferably 10 ⁸ pieces / ml or more. The concentration of the fine bubbles can be measured, for example, with Zetaview (registered trademark) manufactured by Microtrack Bell.

The liquid containing UFB is not particularly limited, and deionized water, potable well water, tap water, and the like generally used for washing fruits and vegetables can be used. Moreover, not only this but aqueous solution, such as ethanol, an acetic acid, an organic acid, can also be used. The liquid may be a single liquid or a mixed liquid. Here, in the manufacturing method of this embodiment, it aims at washing | cleaning of object food, without using hypochlorous acid. For this reason, from the viewpoint of the Food Sanitation Law and the like, the liquid preferably has a chlorine concentration in the liquid due to sodium hypochlorite or the like of less than 20 ppm, and more preferably 1 ppm or less. The chlorine concentration in the liquid can be measured by a known method such as high performance liquid chromatography.

In the present embodiment, a method for generating fine bubbles (UFB) is not particularly limited, and a known method can be used. Examples of the known method include a method of generating UFB by mixing a gas with a liquid and applying a high shearing force or the like to the liquid. More specifically, the liquid in which the gas is mixed can be sent to a mixer or the like having a complicated fluid path with a pump, and the bubbles can be refined by applying a shearing force to the bubbles in the liquid. Moreover, although it changes with apparatuses used, an ideal microbubble can be generated by repeating the bubble miniaturization process several times, for example. The gas mixed with the liquid is not particularly limited, and for example, air, carbon dioxide gas, nitrogen gas, ozone gas, and the like can be used, and carbon dioxide gas, air, and nitrogen gas are preferable. In addition, these gases may be mixed gases as well as single gases. As the UFB generator, a commercially available ultra high density ultra fine bubble generator or the like can be used.

-Jet-
In the cleaning step in the present embodiment, a jet of a liquid containing UFB (hereinafter also referred to as “UFB water”) is used. Here, the “jet flow” is a phenomenon in which a fluid having a velocity is jetted as a substantially one-way flow from the discharge port into the space under pressure. In the washing step, the washing water containing UFB is sprayed for a certain period of time into a washing tank containing the target food to be sterilized and cleaned and mixed with the cleaning target (target food). The washing conditions in the washing step can be determined in consideration of the shape and size of the washing tank, the number and position of the ejection holes, the cut size and specific gravity of the target food (fruit and vegetables) to be washed. On the other hand, the range of the strength of the jet needs to be stronger than the state in which the target fruits and vegetables are sinking or floating, and weaker than the fruits and vegetables are damaged by the jet. From such a viewpoint, in the cleaning step, “cleaning with a jet of liquid containing fine bubbles” means 0.05 volume% or more per second with respect to the volume of the cleaning tank per discharge port and a pressure of 0.01 MPa. This means that the target food is washed with a liquid containing fine bubbles discharged.
Throughout this specification, the pressure for discharging liquid containing fine bubbles from the discharge port is referred to as “discharge pressure” (unit: Pa). The ratio of the amount of liquid containing fine bubbles to the volume of the cleaning tank container discharged into the cleaning tank volume for one second from one discharge port is referred to as “discharge amount” (unit: volume%).
When the discharge pressure of the liquid containing UFB is less than 0.01 MPa or the amount of discharge per second is less than 0.05% by volume of UFB water, the UFB is sufficiently in the surface structure of the target food in which the cells are lurking. It cannot invade and cannot fully exert its bactericidal effect. The discharge pressure is preferably 0.01 to 0.10 MPa, from the viewpoint of the balance between the freshness of the target food (the amount of damage received), the cleaning and sterilization effects, and the factory operating energy. More preferably, it is 0.05 MPa. The discharge amount is 0.05 vol% to 50.00 vol% of the washing tank volume from the viewpoint of the balance between the freshness of the target food (the degree of damage received) and the cleaning and sterilizing effects, and the factory operating energy. It is preferably 0.05 vol% to 5.00 vol%.

-Cleaning conditions-
In the cleaning process of the present embodiment, there is no particular limitation on other cleaning conditions if a jet of liquid containing UFB is used. For example, the cleaning time by the jet of liquid is the freshness of the target food (the degree of damage received). From the viewpoint of the balance between cleaning and sterilization and the operation efficiency of the process, the time is preferably 2 seconds to 30 minutes, more preferably 10 seconds to 5 minutes. In particular, according to the manufacturing method of this embodiment, since a jet is used, a cleaning effect and a sterilizing effect can be achieved in a shorter cleaning time than in the case of immersion shaking. Further, the temperature of the liquid at the time of washing is not particularly limited, but it is preferably 2 to 25 ° C. and more preferably 5 to 15 ° C. from the viewpoint of the bactericidal effect and the freshness of the target food.

In the present embodiment, the configuration of the cleaning tank container (the volume of the cleaning tank, the number of nozzles installed, the installation angle, the hole diameter, etc.) is not particularly limited and can be appropriately selected according to the purpose. The direction of flow of the liquid containing UFB in the cleaning process may be one direction, a system in which liquid collides in a plurality of directions, or a continuous system or a batch system. Good. In addition, the cleaning tank used in the cleaning process may be either an open type or a closed type, and the size can be appropriately determined according to the purpose (type, amount, etc. of target food). The cleaning tank may be configured to generate UFB in the same tank as the water tank used for cleaning, and may be a mechanism that circulates it, or a liquid containing UFB generated by another apparatus. Any mechanism that discharges into the cleaning tank may be used. Moreover, the said washing tank may have a mechanism which can perform ultrasonic irradiation to the liquid containing UFB.

Examples of the bacteria to be sterilized in this embodiment include bacteria that adhere to soil-derived germs and vegetables and reduce their freshness, E. coli, Salmonella, staphylococci, and the like.

As described above, the manufacturing method of the present embodiment may include a process other than the cleaning process. For example, although the manufacturing method of the packaged food of this embodiment includes a cutting process and a packaging process in addition to a cleaning process, other processes are appropriately included before the cleaning process and after the packaging process.
In the case of the packaged food manufacturing method of the present embodiment, it is important that the above-described cleaning process is performed before the cutting process described below. As a result of research by the applicant, most of the bacteria contained in vegetables are present on the surface of vegetables, and a knowledge about 100 times different from the inside has been obtained. Therefore, surface cleaning before the cutting process is extremely effective for sterilization of foods containing vegetables.
Hereinafter, the other steps will be described using the method for producing packaged food of the present embodiment as an example. However, each process described below is not applied only to the packaged food manufacturing method of the present embodiment, and can be appropriately combined with a cleaning process in the manufacturing method of the present embodiment.

(Cutting process)
The cutting process in the manufacturing method of the packaged food of this embodiment is a process of cutting the target food washed by the washing process in a sterile state. The manufacturing method of this embodiment can cut | disconnect a target food, maintaining the bactericidal effect performed in the washing | cleaning process by performing the cutting process in an aseptic state following a washing | cleaning process.

“Sterile condition” means a practically aseptic condition that is usually required according to the target food, and does not have to be completely aseptic. A microbially safe product can be produced within the set shelf life. Indicates the state (environment). For example, as the “sterile state”, as a general standard, the condition that the number of general viable bacteria in the environment is 5 CFU / cm ² or less and the coliform group is negative can be adopted (reference: BC Center for Disease Control. Environmental hygiene monitoring: A guide for Environmental Health Officers, BC Center for Disease Control, October 5, 2010 [searched July 12, 2017], Internet <http://www.bccdc.ca/NR/ rdonlyres / EF1461BE-0301-4A59-8843-420072412721 / 0 / EnvMonitoringHygieneGuideforEHOs.pdf>.

Specifically, although not particularly limited, for example, in order to perform each process (at least the cutting process and the packaging process) in the “sterile state” in the present embodiment, there is a possibility that at least the target food may be contacted. A certain device and the surrounding environment can be based on the condition that the number of viable bacteria in the environment is 5 CFU / cm ² or less and the coliform group is negative.
In addition, examples of the aseptic object include the bacteria to be sterilized as described above. The aseptic condition is, for example, the device used for the cutting process, the floor or wall of the room where the apparatus is installed, other installations, the person performing the cutting process, etc. This can be achieved by applying a sterilization treatment. Further, a clean bench or a clean room may be used in order to maintain aseptic conditions. The aseptic cutting process may be performed through a human hand in a clean bench, or may be automatically performed using an industrial robot or the like.
The aseptic condition is preferably ensured by sterilizing equipment and facilities on the premise that products entering the consumer's mouth and their raw materials do not come into contact with chemical substances such as hypochlorous acid. That is, hypochlorite can be used as a disinfectant for equipment facilities, and it is preferable to combine a plurality of disinfection treatments.

In the method for producing packaged food according to the present embodiment, the cutting (cutting) in the cutting process is not particularly limited as long as the sterility is maintained, and a method usually used according to the target food is appropriately selected. can do. As a cutting method, for example, in the case of fruits and vegetables, various methods such as round cutting, diagonal cutting, strip cutting, chopping, diced cutting, and paste processing can be cited. Moreover, the apparatus used for a cutting process can also be suitably selected according to object food etc.
Further, the processing conditions at the time of cutting are not particularly limited. For example, in a carbon dioxide atmosphere, the humidity (RH) is about 50% to 90%, and the temperature is about 1 ° C. to 15 ° C. (preferably 2 ° C. to 5 ° C. ) Is preferable.

Further, in the method for producing packaged food according to the present embodiment, the dehydration process may be performed on the condition that it is performed in a sterile state before and after the cutting step. The dehydration process is a process for removing liquid from the target food that has been cleaned in the cleaning process. In the dehydration treatment, for example, means such as centrifugal dehydration can be used. In addition, when using a water flow at the time of transferring to a dehydration process from a washing | cleaning process, use of UFB water is preferable at the point which does not need to confirm whether the chemical | medical agent was able to be removed unlike utilization of a chemical chemical.

(Packaging process)
In the method for manufacturing packaged food according to the present embodiment, the packaging step is a step of packaging the target food cut in the cutting step in a sterile state. In the manufacturing method of this embodiment, the target food is packaged while maintaining the sterilizing effect by the washing process, and therefore, after cutting, a sterilizing agent such as hypochlorous acid and a large amount of water for removing the same are removed from the cut surface of the cut vegetables. Etc., and the original flavor and umami of the target food can be maintained. The aseptic condition is synonymous with that in the above-described cutting step, but may be under different conditions from the cutting step as long as the above definition is applied.

In the method for producing packaged food according to the present embodiment, the packaging of the target food in the packaging process is not particularly limited as long as the sterility is maintained, and a known method can be appropriately employed. For example, a method of sealing with a bag filled with an inert gas such as nitrogen gas or a packaging material can be employed, but it is preferable to employ a means that can ensure a sterilized state for a certain period even after packaging. . As such means, food packaging wrap made of vinylidene chloride resin or polyvinyl chloride resin is used, and an appropriate amount is stored in a tray and packed with a wrap film, or vacuum packed, sterilized packaging and removal. Examples include a method using an oxygen agent.

There are no particular restrictions on the packaging conditions. For example, in a carbon dioxide atmosphere, the humidity (RH) is about 50% to 90%, and the temperature is about 1 ° C to 15 ° C (preferably 2 ° C to 5 ° C). It is preferable to carry out.

As mentioned above, although the manufacturing method of this invention, the food obtained by this, and the packaged food were demonstrated with detailed embodiment, the structure of this invention is not limited to the above-mentioned embodiment.

[Examples 1 to 5, Comparative Example 4]
Fresh cabbage sliced to a width of 1 mm (sliced cabbage) or lettuce cut into 5 cm square (cut lettuce) was used as the target food. In each Example and Comparative Example 4, the target food was washed as necessary and then dehydrated by centrifugation (preliminary washing step). The obtained target food was transferred to a water tank and washed and sterilized with a jet of ultra fine bubble water (hereinafter referred to as “UFB water”) filled with ultra fine bubbles in tap water. For UFB water, a device manufactured by Nanocus Co., Ltd. (device name: Nano Fresher (registered trademark)) was used. Specifically, 200 L of tap water was aerated with a predetermined gas under conditions of room temperature and 2 hours using a nano flesher to generate UFB so that the concentration of UFB would be 10 ⁸ pieces / ml or more (UFB concentration (Measured with Zetaview (registered trademark) manufactured by Microtrack Bell). Tables 1 to 3 show the preparation conditions and cleaning conditions of UFB water in each example.

[Comparative Example 1]
Sodium hypochlorite was added to tap water to adjust the chlorine concentration to 180 ppm, and sliced cabbage was immersed in the tap water for 5 minutes for washing and sterilization. The target food was then rinsed with a large amount of tap water. Table 1 shows the cleaning conditions.

[Comparative Example 2]
Sodium hypochlorite was added to tap water to adjust the chlorine concentration to 200 ppm, and sliced cabbage was immersed in the tap water for 5 minutes for washing and sterilization. The target food was then rinsed with a large amount of tap water. Table 1 shows the cleaning conditions.

[Comparative Examples 3-1 to 3-3]
Tap water was jetted at a discharge rate of 1 to 5% by volume and discharge pressure of 0.01 to 0.05 MPa, and the cut lettuce was washed and sterilized for 5, 10 or 15 minutes. Table 2 shows the cleaning conditions.

[Evaluation of cleaning sterilization effect of cut vegetables (cleaning sterilization effect)]
Cut vegetables subjected to the washing treatment for each Example and Comparative Example were enclosed in a plastic bag and stored at 10 ° C. or lower. According to the procedure of general microorganism experiment for each operation, the number of bacteria was examined using the stored sample. For the bacterial count test, 10 g of the stored sample was treated with 90 ml of phosphate buffer (pH 7.0) and stomacher for 1 minute to extract the bacteria. After 10-fold serial dilution, 1 ml of this was applied to the plate. After culturing for 48 hours, CFU / g of general bacteria and coliforms was measured. Based on the measured value, the number of bacteria before and after washing and sterilization was determined to calculate the residual bacteria rate. The “residual bacteria rate” indicates the rate of decrease in the number of general viable bacteria when the untreated sample is taken as 100%.

The state of fine bubbles in UFB water and cleaning conditions in each Example and Comparative Example, and the sterilization rate of the sample are shown below.

 

In Example 1 and Comparative Examples 1 and 2 (using slice cabbage), the residual bacteria rate in the case of the present invention in which the target food was washed by a jet of UFB and the conventional method (method using sodium hypochlorite) ( The difference in the cleaning and sterilization effect was compared. As is clear from the results of Table 1, when compared with the residual bacteria rate, the production method of Example 1 in which the target food was washed by the jet of UFB was equivalent to the conventional method of sodium hypochlorite (Na hypochlorite). The result was shown. From these results, it can be seen that the present invention exhibits the bactericidal action equivalent to the conventional method.
Moreover, the slice cabbage washed in Example 1 had a low residual bacteria rate and had no chlorine odor and maintained its original flavor and umami. On the other hand, although the slice cabbage of Comparative Examples 1 and 2 had a low residual bacteria rate, the odor of chlorine was strong, the flavor and umami of food were impaired, and bitterness was also felt.

 

According to Examples 2-1 to 4-3 and Comparative Examples 3-1 to 3-3 (using cut lettuce), the subject food was washed with a jet of UFB and tap water without using UFB. The difference in residual bacteria rate (cleaning and sterilization effect) was compared with the case where the target food was washed by a jet of water. As is clear from the results in Table 2, in the production methods of each Example in which the target food was washed with a jet of UFB, a remarkable difference was observed in the residual bacteria rate as compared with the case where tap water was simply used. From these results, it can be seen that the present invention can exhibit a sterilization effect that is exceptionally superior to the case of simply washing with tap water jet by using the UFB jet.

 

According to Example 5 and Comparative Example 4 (using slice cabbage), the residual bacteria rate (cleaning sterilization) between the case of the present invention in which the target food was washed by the jet of UFB and the case where the target food was simply immersed in UFB water We compared the difference in effect. As is clear from the results in Table 3, the production method of the present invention in which the target food was washed with a jet of UFB showed a marked difference in the rate of remaining bacteria compared to the case where the target food was simply immersed in UFB water. It was. From these results, it can be seen that the present invention can exhibit a particularly excellent bactericidal action as compared with the case where the target food is simply immersed in UFB water by using the jet of UFB.

[Example 6]
(Preparation process)
First, after cutting and sterilizing at the root (for example, 3 cm width), green onions were washed with tap water to remove impurities such as soil on the surface, and then dehydrated by centrifugation (preliminary washing). Next, the leaf side was cut off to a length of 10 cm (trimming) and used as the target food.

(Washing process)
A green onion (target food) obtained in a clean room in a sterile state at a level where the number of general viable bacteria is 10 ⁵ CFU / g or less and the coliform group is negative (in this example, cut green onion) can be adjusted. .5 kg was transferred to a 10-liter water tank and washed and sterilized at a water temperature of 15 ° C. for 5 minutes with a jet of ultra fine bubble water (hereinafter referred to as “UFB water”) filled with ultra fine bubbles in tap water. Went. For UFB water, a device manufactured by Nanocus Co., Ltd. (device name: Nano Fresher (registered trademark)) was used. Specifically, 200 L of tap water is aerated with carbon dioxide (CO ² ) under conditions of room temperature and 2 hours using a nano flesher so that the diameter of the bubbles is 10 to 500 nm and the concentration is 10 ⁸ cells / ml or more. (The UFB concentration was measured with Zetaview (registered trademark) manufactured by Microtrack Bell). The jet was performed under the conditions of a pressure of 0.01 to 0.05 MPa and a discharge amount of 0.1 to 0.5 L / s.

(Cutting process / packaging process)
Following the cleaning process, the cleaned target food was sterilized and cut into 1 mm thicknesses in a clean room to obtain a product form (cutting process). In addition, the target product was dehydrated (drained) after being cut into rings. Similarly, following the cutting process, the cut target food was sealed in food packaging for aseptic conditions in a clean room (packaging process), and packaged food was produced.

[Comparative Example 5]
Packaged in the same manner as in Example 6 except that the target food was immersed in tap water containing UFB for 5 minutes and pre-washed (“pre-wash” means washing before cutting. The same applies hereinafter). Food was produced. Immersion was performed by allowing the sample to settle.

[Comparative Example 6]
Cut green onions adjusted through the above-mentioned cutting process without pre-washing, adjust sodium chloride to a concentration of 200 ppm by adding sodium hypochlorite to the tap water, wash the target food with a tap of the tap water, and then a large amount A packaged food was produced in the same manner as in Example 1 except that it was rinsed with tap water. The jetting / cleaning conditions (time, water temperature, pressure and discharge rate) were the same as in Example 6. In addition, the chlorine concentration of the used tap water was 1 ppm or less.

[Comparative Example 7]
Packaged food was produced in the same manner as in Example 7, except that the cut green onion adjusted through the above-described cutting process without pre-washing was washed with a tap water jet. The jetting / cleaning conditions (time, water temperature, pressure and discharge rate) were the same as in Example 7. In addition, the chlorine concentration of the used tap water was 1 ppm or less.

[Comparative Example 8]
Packaged food was produced in the same manner as in Example 7 except that the cut green onion adjusted through the above-described cutting step without pre-washing was immersed in tap water for 5 minutes. Immersion was performed by allowing the sample to settle. In addition, the chlorine concentration of the used tap water was 1 ppm or less.

[Evaluation of cleaning sterilization effect (cleaning sterilization effect)]
The packaged food (green onion) produced in each Example and Comparative Example was stored at 5 ° C. or lower.
According to the procedure of general microorganism experiment for each operation, the number of bacteria was examined using the stored sample. For the bacterial count test, 10 g of the stored sample was treated with 90 ml of phosphate buffer (pH 7.0) and stomacher for 1 minute to extract the bacteria. After 10-fold serial dilution, 1 ml of this was applied to the plate. After culturing for 48 hours, CFU / g of general bacteria and coliforms was measured. Based on the measured value, the number of bacteria before and after washing and sterilization was determined to calculate the residual bacteria rate. The “residual bacteria rate” indicates the rate of decrease in the number of general viable bacteria when the untreated sample is taken as 100%.

[Aroma and umami evaluation]
The packaged food manufactured in each Example and Comparative Example was opened, green onions were eaten, and flavor and umami were evaluated according to the following criteria. The evaluation was carried out by using samples from 10 blind persons as a panel. As each evaluation result, 6 or more of the 10 panelists matched.
A: The original flavor and umami of green onions were felt.
B: Although it did not reach the original green onion, flavor and umami were sufficiently felt.
C: The flavor and umami of green onions were impaired.

The conditions and evaluation results in each example and comparative example are shown in the following table.

 

As is clear from the results of Table 4, when compared with the residual bacteria rate, the production method of Example 6 in which the target food was washed with a jet of UFB had a good sterilization rate (residual bacteria rate), and further flavored. And the taste was not impaired. On the other hand, in Comparative Example 6 using sodium hypochlorite, although the sterilization rate was good, the taste was added at the time of actual eating, and the flavor and umami were lost. In Comparative Examples 5, 7 and 8, the flavor and umami were not impaired, but the sterilization rate was not sufficient.

The disclosure of Japanese Patent Application No. 2017-68165 filed on March 30, 2017 and the disclosure of Japanese Patent Application No. 2017-143350 filed on July 25, 2017 are incorporated by reference in their entirety. Incorporated herein.
In addition, all the documents, patent applications, and technical standards described in the specification are as much as if the individual documents, patent applications, and technical standards were specifically and individually stated to be incorporated by reference. , Incorporated herein by reference.

Claims (24)

1. A method for producing food, including a step of washing the target food with a jet of liquid containing fine bubbles having a diameter of less than 1 μm.
2. The method for producing food according to claim 1, wherein the diameter of the fine bubbles is 10 nm to 500 nm.
3. Method for producing a food as claimed in claim 1 or claim 2 concentration of the fine bubbles in the liquid is 10 ⁶ cells / ml or more.
4. The target food is cleaned with a liquid containing the fine bubbles discharged at a rate of 0.05% by volume or more per second and a pressure of 0.01 MPa or more with respect to the volume of the cleaning tank per discharge port. The method for producing food according to any one of the above.
5. The method for producing food according to any one of claims 1 to 4, wherein the cleaning time by the jet of liquid is 2 seconds to 30 minutes.
6. The method for producing food according to any one of claims 1 to 5, wherein the target food is cut food.
7. Food that has been washed by the washing method in the step of washing with a jet of liquid containing fine bubbles having a diameter of less than 1 μm.
8. The food according to claim 7, wherein the diameter of the fine bubbles is 10 nm to 500 nm.
9. Food according to claim 7 or claim 8 the concentration of the micro-bubbles in the liquid is 10 ⁶ cells / ml or more.
10. 10. The liquid according to claim 7, wherein the liquid is washed with a liquid containing the fine bubbles discharged at a pressure of 0.01 MPa or more and a pressure of 0.01 MPa or more per second with respect to a washing tank volume per discharge port. The food according to item 1.
11. The food according to any one of claims 7 to 10, wherein the washing time by the jet of liquid is 2 seconds to 30 minutes.
12. The food according to any one of claims 7 to 11, which is a cut food.
13. A washing step of washing the target food with a jet of liquid containing fine bubbles having a diameter of less than 1 μm;
    A cutting step of cutting the target food washed by the washing step in a sterile state;
    A packaging step of packaging the target food cut in the cutting step in a sterile state;
    A method for producing prepackaged food.
14. The said washing | cleaning process wash | cleans the said target food with the liquid containing the said microbubble discharged by 0.05 volume% or more in 1 second with respect to the washing tank volume per discharge port, and the pressure of 0.01 MPa or more. 13. A method for producing a packaged food according to 13.
15. The method for producing packaged food according to claim 13 or 14, wherein the diameter of the fine bubbles is 10 nm to 500 nm.
16. The method of manufacturing the wrapped food according to any one of the fine bubbles claims 13 to claim 15 concentration is 10 ⁶ cells / ml or more in the liquid.
17. The method for producing packaged food according to any one of claims 13 to 16, wherein the washing time in the washing step is 2 seconds to 30 minutes.
18. The method for producing packaged food according to any one of claims 13 to 17, wherein the target food is a vegetable having a layered structure.
19. Packaged food that has been washed and jetted in a sterile state after being washed by a jet of liquid containing fine bubbles having a diameter of less than 1 μm.
20. The packaged product according to claim 19, which has been cleaned by a jet of liquid containing the fine bubbles discharged at 0.05% by volume or more per second with respect to the volume of the cleaning tank per discharge port and at a pressure of 0.01 MPa or more. food.
21. The packaged food according to claim 19 or 20, wherein the diameter of the fine bubbles is 10 nm to 500 nm.
22. The packaged food according to any one of claims 19 to 21, wherein the concentration of the fine bubbles in the liquid is 10 ⁶ / ml or more.
23. The packaged food according to any one of claims 19 to 22, wherein a cleaning time by the liquid jet is 2 seconds to 30 minutes.
24. The packaged food according to any one of claims 19 to 23, wherein a vegetable having a layered structure is packaged.