Food disinfection methods

Abstract

To improve storable duration of various foods while improving use feeling by suppressing alcoholic smell which is felt before eating, after the use for various foods in household.SOLUTION: A food sterilizing method includes: an adhesion step of adhering a food sterilizing agent containing antibacterial components derived from food, and ethanol to a food stored in a storage body; and an ethanol diffusing step of vaporizing a predetermined amount or more of ethanol in the storage body and diffusing to the outside of the storage body after the adhesion step. After the ethanol diffusing step, the storage body is closed.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a method for sterilizing food that can improve the shelf life of food.

Background Art

[0002] There are known shelf life improvers or preservatives (hereinafter collectively referred to as shelf life improvers) that maintain the freshness of food by exhibiting sterilization, antibacterial, and bacteriostatic effects when used in food.

[0003] For example, Non-Patent Document 1 discloses an alcohol preparation using ethanol as a shelf life improver for food. Since the sterilization and bacteriostatic effects of ethanol are less affected by organic substances, etc., it is excellent in that it can be applied regardless of the type of food. However, since the alcohol preparation loses its efficacy when ethanol volatilizes, when using the alcohol preparation at the food manufacturing site, it is packaged immediately after use, which is also described in Non-Patent Document 1.

[0004] Also, for example, as disclosed in Patent Document 1, in order to enhance the inactivating effect on norovirus, etc., an alcohol preparation containing, in addition to ethanol, grape seed extract, glycerin fatty acid ester, etc. has also been proposed.

[0005] On the other hand, various shelf life improvers that do not use ethanol have also been proposed. For example, preparations using glycine disclosed in Patent Document 2, preparations using lysozyme disclosed in Patent Document 3, etc. are known. Thus, shelf life improvers that do not use ethanol generally need to be properly selected according to the target food because their effects vary depending on the components and pH of the food.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

[0007] [Non-Patent Document 1] Food Washing Association Series 18: Alcohol-Based Preparations - Part 1 - Food Additives (Japan Food Washing and Hygiene Association) [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] In recent years, with the growing awareness of hygiene, the need for food sterilization and disinfection has increased in ordinary households. Furthermore, with the effects of global warming, food poisoning during the summer months is a greater concern than ever before. Therefore, there is a demand for agents that can be used to prevent food poisoning in homemade lunches, for example, that is, home-use shelf-life extenders and instructions on how to use them. In addition to lunches, households store various types of food, such as prepared foods, bread, and fruit, and there is a desire to extend the shelf life of all of these foods.

[0009] However, the conventional shelf-life extenders disclosed in the above-mentioned documents are commercial formulations used in food manufacturing facilities and are not necessarily suitable for use in homemade bento boxes and similar items.

[0010] For example, alcohol-based preparations using ethanol lose their bacteriostatic effect once they evaporate, so they are not sufficiently effective in lunch boxes or bags that are not airtight. While they are effective in airtight lunch boxes, the airtightness of lunch boxes commonly found in households is not very high, often allowing ethanol to evaporate and outside air to enter. Furthermore, even if a highly airtight lunch box is used, when the lid is opened to eat, the alcohol inside will evaporate, resulting in an alcoholic smell, which is problematic for homemade lunches, especially children's lunches. In addition, growing children may eat their lunch in multiple sittings, but with alcohol-based preparations, the bacteriostatic effect cannot be expected after the lunch box lid is opened and closed, so they are not suitable for situations where the lunch is eaten in multiple sittings. The same applies to other foods; for example, if you eat only one slice of bread and store the rest in a bag, the bacteriostatic effect of the above-mentioned alcohol-based preparation cannot be expected.

[0011] On the other hand, shelf-life extenders such as glycine and lysozyme need to be used differently depending on the food and bacteria being prepared, but it is not practical for a household to use different shelf-life extenders for each type of side dish. Furthermore, these types of shelf-life extenders are often used during food manufacturing by methods such as kneading or soaking, but when preparing a bento box at home, it is time-consuming to add shelf-life extenders individually by kneading or soaking each side dish. The same applies to other foods.

[0012] This invention has been made in view of the above, and its purpose is to improve the shelf life of various foods while suppressing the alcohol odor that can be perceived after using various foods at home and before eating them, thereby improving the user experience. [Means for solving the problem]

[0013] To achieve the above objective, the first invention comprises an attachment step of attaching a food disinfectant containing a food-derived antibacterial component and ethanol to food contained in a container, and an ethanol release step of vaporizing a predetermined amount or more of ethanol in the container and releasing it to the outside of the container after the attachment step, and the container is closed after the ethanol release step.

[0014] With this configuration, when food-grade disinfectant is applied to food contained in the container, the antibacterial effect of ethanol and food-derived antimicrobial components is exerted, eliminating bacteria attached to the food. In particular, because it contains ethanol and food-derived antimicrobial components, a wide range of disinfection effects can be obtained regardless of the type of food or bacteria, and the food can be eaten with peace of mind.

[0015] If a food-grade disinfectant is applied and the container is left open, a certain amount of ethanol inside the container will vaporize and be released to the outside. Therefore, even if the container is then sealed, the alcohol smell will be less noticeable before consumption. In addition, since ethanol dries quickly, it will have little effect on the texture.

[0016] Furthermore, after a predetermined amount of ethanol has evaporated, the food-derived antibacterial components remain and exert bacteriostatic and antibacterial effects. This prevents bacterial growth even in containers that are not airtight, such as lunch boxes, or when the container is opened and closed multiple times. In addition, because food-derived antibacterial components and ethanol are used in combination, the amount of food-derived antibacterial components required can be reduced, resulting in a reduced impact on the taste of the food. In the ethanol evaporation process, it is not necessary to evaporate all of the ethanol. This allows some ethanol to remain in the container.

[0017] The second invention is characterized in that, in the adhesion step, the food disinfectant is contained in a spray container, and the food disinfectant sprayed from the spray container is applied to the food.

[0018] According to this configuration, a food disinfectant can be evenly attached to food. Also, since the food disinfectant becomes fine particles, it can enter between foods and the disinfection effect can be obtained even in the depths, and the food disinfectant can also be attached to the inner surface of the container, and the disinfection effect on the inner surface of the container can also be obtained.

[0019] The third invention is characterized in that, in the ethanol diffusion step, more than 20% of the ethanol attached to the food in the attachment step is diffused to the outside of the container.

[0020] That is, when the amount of ethanol attached is set so that a sufficient disinfection effect on food can be obtained in the attachment step, if the remaining amount of the ethanol increases, there is a risk that the alcohol smell when eating the food will become prominent. However, in this configuration, since more than 20% of the ethanol attached to the food is diffused to the outside of the container, the alcohol smell hardly becomes a concern.

[0021] The fourth invention is characterized in that, in the attachment step, the food disinfectant is attached to a plurality of types of foods contained in a lunch box as the container, and after the ethanol diffusion step, the lunch box is closed.

[0022] According to this configuration, instead of using different preservatives for each item of side dishes, after packing the cooked side dishes in a lunch box, it is only necessary to finally attach the food disinfectant to the whole, which is extremely practical in households. Also, since it contains ethanol, a disinfection effect is exerted on a plurality of types of foods such as side dishes and rice.

[0023] The fifth invention is characterized in that a food disinfectant containing citrus seed extract as an antibacterial component derived from food is used in the attachment step.

[0024] According to this configuration, in addition to the antibacterial action against various types of bacteria, a virus inactivation effect can also be exerted.

[0025] The sixth invention is characterized by using a food-grade disinfectant containing at least one of citric acid and lactic acid in the adhesion step.

[0026] This configuration allows for maintaining disinfection even at low ethanol concentrations, further reducing the impact of alcohol odor. [Effects of the Invention]

[0027] According to the present invention, a food-grade disinfectant containing a food-derived antibacterial component and ethanol is applied to the food contained in the container, and then a predetermined amount or more of ethanol from the container is released to the outside of the container before the container is closed. As a result, after using it on various foods at home, the alcohol odor that is perceived before eating is suppressed, improving the user experience, while also improving the shelf life of various foods. [Brief explanation of the drawing]

[0028] [Figure 1] This is a perspective view showing an example of a spray container used in a food disinfection method according to an embodiment of the present invention. [Figure 2] This graph shows the results of feline calicivirus infectivity titer testing. [Figure 3] This graph shows the results of influenza virus infectivity titer testing. [Figure 4] This is a flowchart showing the steps involved in food sterilization. [Modes for carrying out the invention]

[0029] Embodiments of the present invention will be described in detail below with reference to the drawings. The following description of preferred embodiments is essentially illustrative and is not intended to limit the present invention, its applications, or its uses.

[0030] (Spray bottle) Before describing the food disinfection method according to an embodiment of the present invention, the configuration of the spray container 1 containing the food disinfectant will be described with reference to Figure 1. Figure 1 is a perspective view showing an example of a spray container 1 used in the food disinfection method according to an embodiment of the present invention. This spray container 1 comprises a container body 2 in which the food disinfectant is contained and a spray nozzle part 3. The spray nozzle part 3 is detachably attached to an opening (not shown) provided on the upper part of the container body 2 by a screw member 3a. A trigger 4 is attached to the front of the spray nozzle part 3 so as to be able to swing in the front-rear direction. A pump mechanism 5 is housed inside the spray nozzle part 3. An intake pipe (not shown) extending to the bottom of the container body 2 is connected to the intake side of the pump mechanism 5. A spray port 6 is connected to the discharge side of the pump mechanism 5. By swinging the trigger 4, the user can move the pump mechanism 5 and spray the food disinfectant drawn up from the intake pipe to the outside from the spray port 6. The diameter of the particles discharged from the spray nozzle 6 can be set arbitrarily, as long as the particle size is such that the food disinfectant adheres evenly to the food.

[0031] The spray container 1 is not limited to the structure and shape described above, and other structures and shapes can also be used. Although not shown in the figures, for example, it may be a spray container equipped with a push-button that moves back and forth in the vertical direction, or it may be an aerosol container in which the ejected gas is contained together with a food disinfectant.

[0032] (Food-grade disinfectant) Next, we will explain food-grade disinfectants. Food-grade disinfectants are liquids containing at least a food-derived antibacterial component and ethanol as active ingredients, and can be used in general households. As a food-derived antibacterial component, for example, citrus seed extract can be used. An example of a citrus seed extract is grapefruit seed extract. Grapefruit seed extract is extracted and purified from the seeds of grapefruit fruit and is generally approved as a food additive. When obtaining grapefruit seed extract from grapefruit, the seeds are removed from the harvested grapefruit, the removed seeds are crushed, and the extract is obtained from the crushed material. At this time, the grapefruit seed extract may be extracted from the undried crushed material, or it may be extracted from the freeze-dried crushed material.

[0033] When extracting grapefruit seed extract, solutions such as water or alcohol can be used. Examples of alcohols used as extraction solvents include ethanol. When extracting grapefruit seed extract, the seeds may be heated to, for example, 30°C or higher. Grapefruit seed extract contains fatty acids, flavonoids, and other substances. Food-grade grapefruit seed extract is preferred.

[0034] Grapefruit seed extract can be supplied as an aqueous solution. The aqueous solution of grapefruit seed extract is prepared by dissolving grapefruit seed extract in deionized water or the like. The concentration of grapefruit seed extract in this aqueous solution can be set, for example, in the range of 5% to 40% by mass. The lower limit of the concentration of grapefruit seed extract in the food disinfectant is preferably 0.1% by mass, and more preferably 0.15% by mass. The upper limit of the concentration of grapefruit seed extract in the food disinfectant is preferably 3.0% by mass, and more preferably 0.8% by mass.

[0035] From the viewpoint of quick drying, the ethanol content is preferably 40 v / v% or higher, and more preferably 50 v / v% or higher. However, since drying too quickly may result in insufficient disinfection, it is preferable that the upper limit of the ethanol content be 95 v / v% or lower.

[0036] Food-grade disinfectants may contain citric acid. The citric acid content can be, for example, 1.0% by mass or less, and more preferably 0.5% by mass or less. Food-grade disinfectants may also contain lactic acid. The lactic acid content can be, for example, 1.0% by mass or less, and more preferably 0.5% by mass or less. The lactic acid content may be less than or more than the citric acid content. Alternatively, the lactic acid content and the citric acid content may be the same. By using a food-grade disinfectant containing at least one of citric acid and lactic acid, the disinfecting effect can be maintained even with a low ethanol concentration, thus further reducing the impact of alcohol odor.

[0037] Food-grade disinfectants may contain tea distillate. The tea distillate content can be, for example, 0.2% by mass or less, and more preferably 0.1% by mass or less. Tea distillate is obtained by dry distilling tea branches and leaves and extracting their components. The remainder of the food-grade disinfectant can be deionized water.

[0038] (Methods for disinfecting food) Next, a method for disinfecting food using the above-mentioned food disinfectant will be described. The food disinfection method, in a typical household setting, comprises at least an application step of applying the food disinfectant to the food contained in a container, and an ethanol release step of vaporizing a predetermined amount or more of ethanol in the container and releasing it to the outside of the container after the application step. The food disinfection method also includes a step of closing the container after the ethanol release step.

[0039] A "container" refers to a container, bag, box, etc., capable of holding fresh food, pre-processed uncooked food, cooked food, or other prepared foods. Examples of containers and boxes include lunch boxes, jars containing jam or condiments, plastic containers, and storage containers for temporarily storing food. Examples of bags include bags for bread or baked goods, or bags for fruits or vegetables, and these may be made of plastic or paper. A "container" may be a container or bag that can be sealed when closed, or it may be a container or bag that allows some air circulation when closed. Small holes may also be formed in the container, bag, or box. Furthermore, the "container" may be a thin film or sheet, such as plastic wrap.

[0040] The following is a detailed explanation of how to disinfect food, based on the flowchart shown in Figure 4. In step S1, the person using the food disinfectant prepares the food they wish to preserve. As mentioned above, various types of food can be used. Place this food into the container. Then, proceed to step S2 and open the container. If the container is a container or box with a lid, open the lid; if it is a bag, open the opening. The container may be opened wide or only slightly.

[0041] Next, proceed to step S3. In step S3, prepare a spray container 1 containing food disinfectant, for example, as shown in Figure 1. Point the spray nozzle 6 of the spray container 1 towards the food and operate the trigger 4 to spray the food disinfectant directly onto the food. In the case of a bag, you may either insert the spray nozzle 6 into the opening of the bag and then operate the trigger 4, or point the spray nozzle 6 from outside the opening into the bag and then operate the trigger 4. This is the adhesion step. When the container is a lunch box, it usually contains several kinds of side dishes, rice, fruit, etc., but the food disinfectant can be applied to all of these foods at once. Through the adhesion step, the antibacterial effect of ethanol and food-derived antibacterial components is exerted, and bacteria attached to the food are disinfected. In particular, because it contains ethanol and food-derived antibacterial components, a wide range of disinfection effects can be obtained regardless of the type of food or bacteria, and the food can be eaten with peace of mind.

[0042] It is preferable to spray the food disinfectant while moving the nozzle 6 so that it adheres evenly to the food, but if the spray range of the nozzle 6 is sufficiently wide, spraying may be done with the nozzle 6 fixed. It is sufficient to spray the food disinfectant on the same spot on the food at least once, but it may be sprayed two or more times. If the food can be moved, the food disinfectant may be sprayed while moving the food. This allows the food disinfectant to adhere to the entire surface of the food, as well as to food hidden beneath other food items.

[0043] Food disinfectants may be applied to food in forms other than spraying. For example, they may be dropped onto food or applied with a brush or the like.

[0044] Food-grade disinfectant may be applied to the inner surface of the container. By spraying the food-grade disinfectant using spray container 1, it can also be applied to the inner surface of containers other than food, thus disinfecting the inner surface of the container. Application to food and application to the inner surface of the container can be performed in the same process, making it efficient.

[0045] After spraying the food-grade disinfectant, proceed to step S4 and wait for a predetermined time with the container open. In step S3, the food-grade disinfectant containing ethanol adheres to the food and the inner surface of the container. When the container is left open for a predetermined time, the ethanol inside the container vaporizes to a predetermined amount or more. Since the container is open, the vaporized ethanol is released to the outside of the container through the opening. This process is the ethanol release process, and by going through this process, the alcohol odor when eating food can be suppressed. In addition, since ethanol dries quickly, it has little effect on the texture.

[0046] The predetermined time for the ethanol evaporation process can be, for example, the time required to evaporate 20% or more of the ethanol adhering to the food to the outside of the container. That is, for example, if the above adhesion process is performed in an atmosphere with a temperature of 25°C and a humidity of 60%, and then the process moves to the ethanol evaporation process, the time required for 20% or more of the adhering ethanol to evaporate to the outside of the container can be measured in advance, and that time can be set as the predetermined time. Since the vaporization rate of ethanol differs depending on the temperature and humidity, it is more preferable to reproduce the average room temperature and humidity of a typical household in winter and summer, measure the above time, and set the longest time as the predetermined time. The predetermined time can be, for example, 10 seconds or more, and preferably 20 seconds or more.

[0047] In the ethanol release process, more than 50% of the ethanol adhering to the food may be released to the outside of the container, or more than 80% may be released to the outside of the container. This further reduces the alcohol odor when consuming the food.

[0048] However, in terms of bacteriostatic effect, it is preferable for a certain amount of ethanol to remain inside the container. Also, in the ethanol release process, the rate of ethanol release gradually slows down over time, so the effect of releasing ethanol is highest in the first few tens of seconds. In other words, there is little benefit in making the above predetermined time too long. Therefore, the upper limit time can be set so that the amount of ethanol remaining is such that there is an effect of reducing the alcohol odor and a bacteriostatic effect is obtained. The upper limit time is, for example, 1 minute or less, preferably 30 seconds or less.

[0049] Next, proceed to step S5 and close the container. If the container is a container or box with a lid, close the lid; if it is a bag, close the opening. At this time, the container may be airtight to prevent any circulation of outside air, or it may be closed to the extent that some circulation of outside air is possible. If the container is a lunch box, close the lid. By closing the container, the bacteriostatic and disinfectant effects of the residual ethanol can be obtained.

[0050] Furthermore, after the ethanol evaporates, the food-derived antibacterial components remain and exert bacteriostatic and antibacterial effects. This prevents bacterial growth even in containers that are not airtight, such as lunch boxes, or when the container is opened and closed multiple times. In addition, because food-derived antibacterial components and ethanol are used in combination, the amount of food-derived antibacterial components required can be reduced, resulting in a reduced impact on the taste of the food.

[0051] (Antibacterial testing) Next, we will explain the antibacterial test results for the above-mentioned food-grade disinfectant. First, we will explain the method of the antibacterial test. The test agents prepared were the example and comparative example shown in Table 1. The comparative example had a higher ethanol concentration than the example, but did not contain grapefruit seed extract.

[0052] [Table 1]

[0053] Table 2 shows the results of the antimicrobial test on the surface of the plastic plates. In this antimicrobial test, each test agent shown in Table 1 was sprayed onto the surface of the plastic plates. After spraying, the plates were left to stand for 24 hours, and then E. coli solution was dropped onto the surface of each plastic plate. The number of bacteria was counted after 18 hours. By the time the E. coli solution was dropped onto the plates, all of the ethanol had evaporated.

[0054] [Table 2]

[0055] In the example, an antibacterial effect of over 99.99% was observed, but in the comparative example, no antibacterial activity was observed. In the example, sterilization was mainly achieved by antibacterial components derived from food, indicating that antibacterial components derived from food are the active ingredients.

[0056] Next, Table 3 shows the results of the antibacterial test on food surfaces at room temperature. In this test, the surfaces of strawberries and hamburgers were sprayed with each of the test agents shown in Table 1. After spraying, the samples were left to stand in the air for 10 minutes. This was done to allow airborne bacteria to adhere to the food. During this time, most of the ethanol had evaporated.

[0057] Each food item was sealed in its container with the lid closed and stored at 28°C for one month, and the degree of mold growth was checked.

[0058] [Table 3]

[0059] In the examples, mold growth was suppressed on the strawberries, with mold only occurring in less than 1 / 8 of the total surface area. In the examples, no mold growth occurred on the hamburgers. This is mainly due to the suppression of mold growth by antimicrobial components derived from food. In other words, even if all the ethanol is released during the ethanol release process, the remaining antimicrobial components derived from food can provide a disinfecting effect. On the other hand, in the comparative examples, mold grew on the entire surface of both the strawberries and the hamburgers.

[0060] Next, Table 4 shows the results of a food preservation test under refrigeration. In this test, raw pork belly and raw shredded cabbage were placed in separate containers and left to stand in the air for 10 minutes. This was done to allow airborne bacteria to adhere to the food. After that, each food was sprayed with the respective test agent shown in Table 1, and then left to stand for approximately 20 seconds. During these 20 seconds, some of the ethanol in each of the examples and comparative examples vaporized and was released outside the container (some ethanol remained inside the container). After approximately 20 seconds, the lids of the containers containing each food were closed, and the food was sealed and stored at 5°C for one week to check the degree of deterioration.

[0061] [Table 4]

[0062] In both the example and the comparative example, discoloration of raw pork belly was suppressed. Similarly, discoloration of raw shredded cabbage was suppressed in both the example and the comparative example. Thus, improved shelf life of refrigerated foods was confirmed. Despite having a lower ethanol concentration than the comparative example, the example achieved a comparable improvement in shelf life. This is likely because the growth of bacteria was suppressed by antibacterial components derived from the food, along with some residual ethanol in the container.

[0063] (Tests to inhibit bacterial growth in other foods) Next, we will describe the bacterial growth inhibition test in other foods. The foods prepared were boiled broccoli, boiled noodles (instant yakisoba noodles), bacon, and omelet, as shown in Tables 5-8. The test method is as follows. 1. Measure 10g of each food item into a plastic cup. 2. Leave each food item uncovered in the air for 10 minutes. This is to allow airborne bacteria to adhere to the food. 3. Spray the food-grade disinfectant evenly over the entire food item (application step). Then, let it stand for approximately 20 seconds (ethanol release step). During this ethanol release step, some of the ethanol will vaporize and be released outside the cup. After approximately 20 seconds, cover the cup. For the untreated item, cover the cup without spraying it with food-grade disinfectant. 4. Leave the samples at a temperature of 4.35°C for a set period of time (4 hours, 8 hours) to allow the bacteria to grow. 5. Add 90g of physiological saline solution to each food item, then crush and mix the food using a hand mixer. Each suspension obtained in 6.5 is serially diluted, and 0.2 ml of each is seeded onto SCDLP agar or mannitol salt agar for confirmation of the bactericidal effect. 7.Count the number of bacteria after 2 days of incubation.

[0064] [Table 5]

[0065] [Table 6]

[0066] [Table 7]

[0067] [Table 8]

[0068] For all food products, the examples demonstrate a higher sterilization effect compared to the untreated samples. However, some bacterial growth was observed in the broccoli samples in the examples. This is likely because the complex and intricate shape of the broccoli prevented even spraying of the disinfectant across its surface.

[0069] (Flavor of food after processing) Next, we will describe the flavor test of food after disinfection treatment with a food-grade disinfectant. The food items prepared are shown in Table 9: sausage, omelet, and raw pineapple.

[0070] The testing method is as follows: 1. Cut each food item into bite-sized pieces and place them in a plastic cup. 2. Spray the food-grade disinfectant evenly over the entire food item (adhesion step). Then, let it stand for approximately 20 seconds (ethanol release step). During this ethanol release step, some of the ethanol will vaporize and be released outside the cup. After approximately 20 seconds, cover the cup. For the untreated option, cover the cup without spraying the food-grade disinfectant. Covering the cup creates a nearly airtight seal, and ethanol remains inside. 3. After covering the food, the monitors were asked to eat both the sample and the untreated sample for 2-4 hours and rate the taste on a 5-point scale. The monitors were given the same taste for both the untreated and sample samples, but were not told which was the sample. There were 12 monitors. They were asked to rate the taste on a scale of 5 to 1, with 4, 3, and 2 points representing their subjective opinions, ranging from 5 points for extremely delicious to 1 point for not delicious. The average scores are shown in Table 9.

[0071] [Table 9]

[0072] As shown in this table, there was almost no difference in taste between the untreated product and the product treated according to the examples. In other words, the ethanol decomposition process can be used to prevent a deterioration in the taste of each food product.

[0073] (Confirmation of ethanol emission) When the food-grade disinfectant of the example was sprayed evenly into a 600 mL plastic container (without a lid) at room temperature, and the amount of mass reduction of the liquid was measured, the remaining percentage was approximately 90% by weight after 20 seconds, approximately 80% by weight after 1 minute, and approximately 55% by weight after 4 minutes. In other words, after 20 seconds, approximately 10% by weight of the example was released to the outside of the container. Here, the example originally contained 52.3% by weight of ethanol, so if the total amount of released mass is ethanol, then approximately 20% of the original ethanol was released. After 1 minute, approximately 20% by weight of the example was released, but if the total amount of released component is ethanol, then approximately 40% of the original ethanol was released.

[0074] In other words, in the "Flavor of Food After Treatment" test described above, the food was left to stand for about 20 seconds during the ethanol release process, and it is estimated that about 20% of the ethanol was released during this time. Thus, by going through an ethanol release process that releases about 20% of the ethanol, it is possible to prevent a deterioration in the taste of each food product.

[0075] (Efficacy against feline calicivirus) Next, we will explain the viral infectivity titer measurement test before and after treatment with a virus inactivating agent. In this test, feline calicivirus is used, but this feline calicivirus is used in the test as a substitute for norovirus, which has a very similar structure. This is because norovirus is difficult to culture, and a method for easily evaluating its infectivity titer has not yet been established. In other words, it is generally believed that if an agent shows sufficient antiviral activity in a test using feline calicivirus, it will also show sufficient antiviral activity against norovirus.

[0076] When performing a viral infectivity test, cells are first cultured in a monolayer in a cell culture microplate (96 wells) using cell growth medium. The cells used are CRFK cells. Then, a diluted viral suspension of feline calicivirus (FCV) is inoculated into these monolayer cultured cells, and the cells are adsorbed in a carbon dioxide incubator (CO2 concentration: 5%) at 37°C ± 1°C for 1 hour. After that, the viral inoculum is removed, and cell maintenance medium is added and the cells are cultured for 4 to 7 days. After that, the cells are stained with amide black to confirm their viability, and the 50% tissue culture infectious titer (TCID50 / ml) is calculated using the Reed-Muench method. A lower value indicates lower infectivity.

[0077] Furthermore, non-enveloped viruses such as feline calicivirus generally have greater resistance to various disinfectants and antibacterial agents than enveloped viruses such as influenza virus. Therefore, an agent that is effective against non-enveloped viruses is likely to be effective against enveloped viruses in a shorter time.

[0078] Figure 2 shows the results of feline calicivirus infectivity titer testing. In the graph, "10 seconds" indicates a contact time of 10 seconds between the test agent and the virus, and "30 seconds" indicates a contact time of 30 seconds. A 10-second contact test can be called a short-term contact test, while a 30-second contact test can be called a long-term contact test. The values ​​in the graph are the logarithm of the infectivity titer TCID50 / ml (logTCID50 / ml). Sterile water was used as the control. The lower the logTCID50 / ml of the test agent compared to the control, the higher the antiviral activity. From the results shown in Figure 2, it can be seen that the example is effective even against feline calicivirus, which is difficult to treat with the comparative example.

[0079] (Efficacy against enveloped viruses) To confirm efficacy against enveloped viruses, the efficacy test procedure for feline calicivirus should be modified as follows: Influenza virus (A / Udorn / 72(H3N2)) is used, and trypsin is added to the cell maintenance medium using MDCK cells.

[0080] Figure 3 shows the results of the influenza virus infectivity titer measurement test. The results in Figure 3 demonstrate that the example is effective against feline calicivirus, which is also difficult to treat with the comparative example.

[0081] (Effects of the embodiment) As described above, according to this embodiment, a food-grade disinfectant containing food-derived antibacterial components and ethanol is applied to the food contained in the container, and then a predetermined amount or more of ethanol from the container is released to the outside of the container before the container is closed. As a result, after using it on various foods at home, the alcohol odor that is perceived before eating is suppressed, improving the user experience, while also improving the shelf life of various foods.

[0082] The embodiments described above are merely illustrative in all respects and should not be interpreted restrictively. Furthermore, any modifications or changes that fall within the equivalent scope of the claims are all within the scope of the present invention. [Industrial applicability]

[0083] As described above, the present invention can be used, for example, as a method to improve the shelf life of various foods in an ordinary household. [Explanation of Symbols]

[0084] 1. Spray container 2. Container body 3. Spray nozzle section 4 Trigger 5. Pump mechanism 6 spray nozzle

Claims

1. A food-grade disinfectant containing citrus seed extract as a food-derived antibacterial component and ethanol is applied to multiple types of food contained in a lunch box in an application process. The process includes, after the aforementioned adhesion step, an ethanol release step in which 20% or more of the ethanol inside the lunch box is vaporized and released to the outside of the lunch box. A method for disinfecting food, characterized by performing the ethanol release step for 10 seconds or more, and then closing the lunch box.

2. In the method for disinfecting food according to claim 1, A method for disinfecting food, characterized in that, in the application step, the food disinfectant is contained in a spray container, and the food disinfectant sprayed from the spray container is applied to the food.

3. In the method for disinfecting food according to claim 1 or 2, A method for disinfecting food, characterized in that a food-grade disinfectant containing at least one of citric acid and lactic acid is used in the application step.

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