JP2015116159A - Cooked food product inclusion body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooked food product inclusion body preservable in a chilled state for a long term while retaining the original taste, flavor and appearance of a food product, and a preservation method of a cooked food product.SOLUTION: The cooked food product inclusion body includes a sealed packaging container, and a cooked food product included in a housing space of the packaging container. Oxygen, carbon dioxide and nitrogen are included in the housing space, and an oxygen concentration in the housing space is 1 vol.%-10 vol.%. Alternatively, oxygen, carbon dioxide and nitrogen are included in the housing space, an oxygen concentration in the housing space is 1 vol.%-10 vol.%, and a carbon dioxide concentration is 20 vol.%-50 vol.%. The cooked food product contains a bacteriostatic agent, and a ratio of the volume of the cooked food product, occupying the volume of the housing space is 20-80%.

Description

  The present invention relates to a cooked food inclusion that can be stored for a long time in a chilled state, and a method for storing cooked food.

  2. Description of the Related Art In recent years, due to changes in lifestyle habits, there is an increasing number of cooked foods such as lunch boxes and prepared dishes that are not cooked at home and eaten at home. In general, cooked foods are manufactured in large quantities in factories and in-store kitchens, and then delivered or displayed in stores. Therefore, a long time may elapse between manufacture and eating at home. For this reason, cooked foods that are mass-produced and sold in stores are usually devised to maintain the quality of the food for a long period of time.

  When storing cooked foods for a long period of time, the problem is the spoilage and alteration of foods caused by the growth of microorganisms. In particular, spore bacteria such as Bacillus and Clostridium are problematic because they have high heat resistance and are not easily sterilized by heating during normal cooking. Among bacteria other than spore bacteria, a group of bacteria having high heat resistance such as microbacteria is difficult to control because it is difficult to sterilize in a normal cooking process.

  Conventionally, as a means for suppressing the growth of microorganisms in cooked foods and maintaining their quality, addition of preservatives and shelf life improvers has been generally performed. Examples of preservatives include basic peptides such as sorbic acid, benzoic acid, protamine, and polylysine. Examples of shelf life improvers include organic acids such as acetic acid, fumaric acid, and adipic acid, or salts thereof, and amino acids such as glycine and alanine. Many substances such as lower fatty acid esters, sucrose fatty acid esters, vitamin B1 esters, hydrous ethanol, polymerized phosphoric acid and the like are known.

  As conventional food storage means, frozen storage and pressure heat sterilization (retort) are also known, but these means require expensive equipment and complicated temperature control, and the taste and texture of food. , The flavor may be impaired.

  In addition, it is known that the growth of microorganisms in food can be suppressed by storing the food in the absence of oxygen and in the presence of an inert gas. For example, Patent Document 1 describes, as a method for preventing corruption of cooked food, sealing cooked food in a container and setting the carbon dioxide concentration in the container to 5% or more and the oxygen concentration to 5% or less. ing. In Patent Document 1, it is preferable to keep the oxygen concentration in the container 1% or less in order to keep the inside of the container in a bacteriostatic state to prevent spoilage and to maintain the aroma, taste, flavor, etc. In the examples, the amount of residual oxygen in the container when the cooked food is sealed in the container is set to 0.4%, and the heat resistant bacteria belonging to the genus Bacillus of the example are set. Effectiveness is shown.

  Patent Document 2 discloses that as a method for producing a chilled distribution sealed food with good storage stability, a predetermined amount of an organic acid salt is added to unheated non-heated food to maintain the pH at 6 to 7, and the non-heated food Is heated in a condition such that the product temperature is 100 ° C. or lower, and then sealed in a container having a carbon dioxide concentration of 5% or more. In Patent Document 2, it is preferable that the oxygen concentration in the container is 1% or less in order to keep the inside of the container in a bacteriostatic state to prevent spoilage and to maintain the aroma, taste, flavor, etc. of the food. It is also described that the method described in Patent Document 2 is particularly effective against Bacillus spore bacteria.

  In Patent Document 3, as a method for preserving non-heated fresh food such as fruits and vegetables, the food is housed in an airtight container together with an organic oxygen absorber and an iron oxygen absorber, In which the gas composition is 10% or less, carbon dioxide 10-0.5%, nitrogen 99-82%. It is also described that the cooling is carried out at a temperature at which no or almost no freezing.

JP 58-98072 A JP 60-164468 A Japanese Patent Laid-Open No. Sho 63-137643

  In the techniques described in Patent Documents 1 and 2, during the preservation of cooked foods, the growth or toxin production of other thermostable microorganisms other than the genus Bacillus (for example, Clostridium botulinum) cannot be suppressed, and in a chilled state A cooked food that can be stored for a long time cannot be obtained.

  The subject of this invention is related with the preservation | save method of the cooked food inclusion body which can provide the cooked food which can be preserve | saved for a long time in a chilled state, maintaining the original taste, flavor, and external appearance of food.

  As a result of earnest research to solve the above problems, the present inventors have encapsulated a cooked food that does not contain a bacteriostatic agent in an accommodation space in a packaging container that contains oxygen, carbon dioxide, and nitrogen, and By setting the oxygen concentration of the storage space to 1% by volume or more and 10% by volume or less, the growth of the thermostable microorganisms or the toxin production in the chilled food while maintaining the original taste, flavor and appearance of the food, The present inventors have found that toxin production of Clostridium botulinum, which is a kind of Clostridium spore bacteria, is effectively suppressed (first finding).

  In addition to setting the oxygen concentration in the accommodation space to the specific range, the inventors further include a bacteriostatic agent (organic acid salt) in the cooked food, and the dioxide in the accommodation space. Growth of heat-resistant microorganisms other than Clostridium botulinum (Bacillus genus, Microbacterium genus) by setting the carbon concentration and the ratio of the volume of the cooked food occupying the volume of the storage space to a specific range, respectively. It was also found that the suppression effect is further increased (second finding).

  The present invention has been made based on the first knowledge, and is a cooked food enclosure comprising a sealed packaging container and a cooked food sealed in a storage space in the packaging container. In the cooked food inclusion body, oxygen, carbon dioxide and nitrogen are contained in the accommodation space, and the oxygen concentration of the accommodation space is 1% by volume or more and 10% by volume or less.

  Moreover, this invention was made | formed based on the said 2nd knowledge, Comprising the cooked food enclosed including the sealed packaging container and the heat-cooked food enclosed in the accommodation space in this packaging container And the storage space contains oxygen, carbon dioxide and nitrogen, and the storage space has an oxygen concentration of 1% by volume to 10% by volume and a carbon dioxide concentration of 20% by volume to 50% by volume. The cooked food contains a bacteriostatic agent, and is a cooked food inclusion body in which the ratio of the volume of the cooked food to the volume of the accommodation space is 20 to 80%.

  The present invention has been made on the basis of the first and second findings, wherein the cooked food is enclosed in a storage space of a sealable packaging container, and the storage space contains oxygen, carbon dioxide and nitrogen. In addition, a gas replacement step of replacing the gas in the storage space so that the oxygen concentration in the storage space is 1% by volume or more and 10% by volume or less, and the cooking that is enclosed in the packaging container after the gas replacement step A method for preserving cooked food, comprising the step of preserving the finished food together with the packaging container in a chilled state.

  ADVANTAGE OF THE INVENTION According to this invention, the cooked food inclusion body which can provide the cooked food which can be preserve | saved for a long time in a chilled state, maintaining the original taste, flavor, and external appearance of food, and the preservation | save method of a cooked food are provided. . According to the present invention, the growth of microorganisms or toxin production in cooked foods can be controlled over a long period of time in a chilled temperature range from around 0 ° C. to around 10 ° C. Therefore, it is complicated and costly such as frozen storage. It becomes possible to distribute and sell cooked foods without the need for temperature control. Examples of microorganisms whose growth or toxin production is suppressed in the present invention include spore bacteria such as Bacillus genus and Clostridium genus, and heat-resistant bacteria such as Microbacterium genus.

The cooked food inclusion body of the present invention will be described based on its preferred embodiment. The cooked food enclosure of the first embodiment of the present invention is a cooked food enclosure comprising a sealed packaging container and a cooked food enclosed in a storage space in the packaging container. The storage space contains oxygen (O ₂ ), carbon dioxide (CO ₂ ), and nitrogen (N ₂ ), and the oxygen concentration in the storage space is 1% by volume to 10% by volume, and the carbon dioxide concentration is The cooked food contains a bacteriostatic agent, and the ratio of the volume of the cooked food to the volume of the accommodation space is 20 to 80%. The cooked food inclusion body according to the first embodiment exhibits an excellent growth inhibitory effect against microorganisms belonging to the genus Bacillus and Microbacterium as well as Clostridium microorganisms (Botulinum).

  The cooked food inclusion body of the first embodiment is obtained by sealing cooked food in a packaging container by gas replacement packaging. The cooked food is a food obtained by cooking one or more kinds of various ingredients (meat, vegetables, fish, etc.), and the kind and cooking method are not particularly limited. ) May be heated not only once but also twice or more. Examples of cooked foods include various side dishes, specifically, boiled foods, grilled foods, boiled foods, steamed foods, fried foods, fried foods, soups, noodles, rice, breads, confectionery And the like.

  As an example of the cooked food, there is a food that has been heated for 1 minute or more under the condition that the center temperature is 75 to 90 ° C. Here, the “center temperature” refers to the temperature of the portion that takes the longest time to heat up when the whole food is heated uniformly to raise the temperature of the food. For example, it can be measured by a memory type thermometer data trace (Nishihana Sangyo). If the cooked food is cooked under such conditions (heating temperature, heating time), such as spore bacteria such as Bacillus and Clostridium and microbacteria that are bacteriostatically targeted in the present invention. Non-heat-resistant fungi other than those with strong heat resistance can be sterilized.

  The cooked food inclusion body according to the first embodiment includes one or more kinds of cooked food. When the cooked food inclusion body of the first embodiment includes two or more kinds of cooked foods, the combination of two or more kinds may be a combination of different kinds of different side dishes, a combination of side dishes and rice, or the like. It can be set arbitrarily depending on the situation.

  The cooked food contains a bacteriostatic agent (antibacterial agent). By containing a bacteriostatic agent in the cooked food, it is possible to effectively suppress the growth of heat-resistant microorganisms in the chilled cooked food, particularly the growth of Bacillus and Microbacterium microorganisms. Examples of the bacteriostatic agent that can be contained in the cooked food include organic acid salts. Examples of the organic acid salt (bacteriostatic agent) include sodium salts, potassium salts, calcium salts, and the like of organic acids such as acetic acid, citric acid, lactic acid, tartaric acid, and fumaric acid. Two or more kinds can be used in combination. Among these organic acid salts (bacteriostatic agents), sodium acetate is particularly preferable.

  The content of the organic acid salt (bacteriostatic agent) in the cooked food is preferably 0.1 to 1.0% by mass, more preferably 0.1 to 0.1%, based on the total mass of the cooked food. It is 35 mass%, More preferably, it is 0.1-0.25 mass%. If the content of the organic acid salt (bacteriostatic agent) in the cooked food is too small, the significance of adding the organic acid salt (suppression of growth of heat-resistant microorganisms) is poor, and if the content is too large, the food is cooked There is a possibility that the acidity of the food increases and the original taste and flavor of the food are lost.

  As a packaging container constituting the cooked food inclusion body of the first embodiment, a packaging container manufactured from a material normally used for gas replacement packaging of food, for example, a gas barrier or oxygen barrier resin or metal is used. Can be used. Examples of such packaging container materials include metals such as aluminum, polyvinyl alcohol (PVA), nylon (NY), ethylene / vinyl alcohol copolymer (EVOH), polyvinylidene chloride (PVDC), polyethylene terephthalate ( PET), polyvinyl chloride (PVC), aluminum laminate (AL), aluminum vapor deposition film (VM), silica vapor deposition film, PET / NY / polypropylene (PP) or polyethylene (PE), PET / NY / AL / PP or PE , PP / EVOH / PE, PP / PVA / PE and the like, but are not limited thereto.

  Moreover, the packaging container should just have the accommodation space which can accommodate the cooked food directly or indirectly inside, and can be sealed, The shape and dimension are not restrict | limited in particular. The shape of the packaging container can be arbitrarily selected from, for example, a tray, a cup, a bag, a box, a can, and the like. Here, “food can be stored directly” means that the food can be stored as it is without being packaged, and “food can be stored indirectly” is stored in a container other than the packaging container. It means that the prepared food can be stored in the separate container. The cooked food inclusion body of the first embodiment includes not only the former (form in which food is directly contained in the packaging container) but also the latter (form in which food is indirectly contained in the packaging container). The material, shape, and dimensions of the other container accommodated in the packaging container are not particularly limited, and can be configured in the same manner as the packaging container. If the open container is in communication, the effect of easy gas replacement is achieved.

  The accommodation space in the packaging container may be a single space without a partition member, or may be divided into a plurality of small spaces by the partition member. When the accommodation space in the packaging container is divided into a plurality of small spaces, it is possible to arrange one or more kinds of cooked foods in each small space, for example, one kind of heating Applying cooked food inclusions to various packaging forms such as a form in which cooked food is divided into a plurality of persons and packaged, or two or more types of cooked food are packaged separately in each type It becomes possible. When a plurality of small spaces in the accommodation space in the packaging container are in communication with each other, an effect of easy gas replacement is achieved. In addition, the said another container accommodated in the accommodation space in a packaging container may be divided into several small space similarly to a packaging container.

  The volume of cooked food (if two or more cooked foods are contained) that occupies the volume of the storage space of the packaging container (the total of those volumes if divided into multiple small spaces) The ratio of the total volume) (occupation ratio of food storage space) is preferably 20 to 80%, more preferably 20 to 70%. If such a ratio is too small, a) the packaging container is too large for the cooked food, the balance is bad, and the food tends to lose its shape; b) the amount of gas of a specific composition existing in the accommodation space increases. Due to the above, the chance of contact with oxygen in the food becomes high, the degree of progress of oxidation of the food becomes strong, c) the chance of contact with carbon dioxide in the food becomes high, and the carbonic acid taste increases. On the other hand, if the ratio is too large, the amount of gas having a specific composition existing in the accommodation space is reduced, resulting in heat-resistant microorganisms (particularly Bacillus and microbacterium) in cooked foods. There is a possibility that the growth inhibitory effect of the genus microorganisms will be reduced.

  As described above, the cooked food inclusion body according to the first embodiment is 1) that the cooked food contains a bacteriostatic agent, and 2) that the accommodation space occupancy of the food is 20 to 80%. And 3) the carbon dioxide concentration in the storage space of the packaging container is 20% by volume to 50% by volume, and 4) the oxygen concentration in the storage space is 1% by volume to 10% by volume. The following structural requirements are also provided. Only when all the above 1) to 4) are satisfied, while maintaining the original taste and flavor of the cooked food, a plurality of heat-resistant microorganisms (Bacillus, Microbacterium, It is possible to effectively inhibit the growth of Clostridium or the like) or toxin production. In particular, the above 1) to 3) are effective for suppressing the growth of microorganisms belonging to the genus Bacillus and Microbacterium, and the above 4) is effective for suppressing the toxin production of microorganisms belonging to the genus Clostridium (Botulinum bacterium).

  When the oxygen concentration in the packaging container's storage space is less than 1% by volume, the toxin production inhibitory effect of Clostridium botulinum is particularly poor. On the contrary, when the oxygen concentration exceeds 10% by volume, oxidation of cooked foods, Odor due to oxidation, fading and discoloration of green and yellow vegetables are likely to occur, and there is a risk that the original taste and flavor of the food may be lost. There is also a risk that Bacillus sp. Oxygen is effective for the growth of some thermostable microorganisms such as Clostridium botulinum or to suppress toxin production, but it is rather useful for Bacillus spore bacteria, etc. Too high is not preferable from the viewpoint of not only the taste and flavor of the cooked food but also the storage stability of the cooked food. The oxygen concentration in the accommodation space in the packaging container is preferably 1 to 5% by volume, more preferably 1 to 3% by volume.

  In addition, even if the above 1) and 2) are provided, if the carbon dioxide concentration in the storage space of the packaging container is less than 20% by volume, microorganisms belonging to the genus Bacillus and Microbacterium (heat-resistant microorganisms other than Clostridium botulinum) In contrast, when the concentration of carbon dioxide exceeds 50% by volume, the sourness of the cooked food increases and the original taste and flavor of the food may be lost. The carbon dioxide concentration in the housing space in the packaging container is preferably 20 to 40% by volume, more preferably 25 to 35% by volume.

  In the cooked food enclosure of the first embodiment, the accommodation space of the packaging container contains nitrogen as a gas component in addition to oxygen and carbon dioxide. For example, when the gas components existing in the storage space of the packaging container are only three components of oxygen, carbon dioxide, and nitrogen, the remainder when the oxygen and carbon dioxide concentrations are within the above ranges is the nitrogen concentration of the storage space. is there.

  In the cooked food inclusion body according to the first embodiment, the accommodation space of the packaging container has a gas component other than oxygen, carbon dioxide, and nitrogen, for example, helium (He), neon (Ne), argon (Ar), and the like. An inert gas may be present. In addition, the gas composition of the accommodation space of the packaging container in the cooked food inclusion body can be measured by a commercially available gas analyzer (for example, trade name “CheckMate”, manufactured by PBI Dancer).

  The method for adjusting the gas composition of the storage space of the packaging container to the specific range is not particularly limited, but a general method includes a gas replacement method in which a gas originally existing in the storage space is replaced with a gas having a specific composition. . As specific examples of the gas replacement method, for example, i) a method of flushing a gas of a specific composition into a storage space in a packaging container in which cooked food is stored, and replacing the gas in the container, ii) cooked For example, a method of filling a gas having a specific composition after vacuuming the housing space in the packaging container containing the food. In the gas replacement method, the gas replacement rate in the housing space of the packaging container is usually 95% or more. In the above i) and ii), as the gas having a specific composition to be filled in the housing space of the packaging container, the oxygen concentration in the sealed housing space is 1% by volume to 10% by volume, and the carbon dioxide concentration is 20% by volume or more. The gas may be 50% by volume or less, and may contain the inert gas in addition to oxygen, carbon dioxide, and nitrogen.

  The cooked food inclusion body of the first embodiment can be stored for a long time in a chilled state. Here, the “chilled state” basically refers to a state where the average temperature of the storage environment of the cooked food inclusion body is in the range of 0 ° C. to 10 ° C., but the average temperature is not necessarily within the specific range. It is not limited to the above, and the specific range is unintentionally caused by the operation status of the refrigeration system for creating a chilled state, or the work of transferring, carrying in, and out of the cooked food inclusion body. The temperature deviation is usually about ± 2 ° C. in terms of the temperature of the cooked food enclosure itself (article temperature). Therefore, in consideration of this unintended temperature fluctuation range, the chilled state can be paraphrased as a state in which the product temperature of the cooked food inclusion body is maintained at -2 ° C to + 12 ° C.

  The cooked food inclusion body according to the first embodiment can be stored for a long time even in a temperature range of 8 ° C. to 10 ° C., which is a high temperature range even in the chilled state, and reduces labor and cost for handling in a lower temperature range. It is extremely useful. Here, “long-term storage” usually depends on the type of cooked food inclusions, but is usually 7 days or longer, preferably 10 days or longer, more preferably 14 days or longer, more preferably 21 days or longer. Say preservation.

In the food (heated and cooked food) enclosed in the cooked food inclusion body of the first embodiment, the growth of microorganisms is suppressed over a long period of time, and per 1 g of the food after the “long-term storage”. The microbial count can be kept below 1 × 10 ⁵ . Examples of microorganisms in which growth or toxin production is suppressed in the first embodiment are as described above, and the cooked food inclusion bodies in the first embodiment include Clostridium (Botulinum), Bacillus, and Microbacterium. Excellent growth or toxin production inhibitory effect on microorganisms such as As described in Patent Documents 1 and 2, in the preservation method in which the oxygen concentration in the packaging container is 1% or less, the growth of Bacillus spore bacteria or toxin production in a chilled cooked food can be suppressed. However, toxin production of Clostridium botulinum in the food cannot be suppressed. In addition, the measurement of the number of microorganisms in food can be performed according to a known method such as a flat plate coating method.

  Next, although the cooked food inclusion body of 2nd Embodiment of this invention is demonstrated, about 2nd Embodiment, a different part from 1st Embodiment mentioned above is mainly demonstrated, and it is the same as that of 1st Embodiment. Description of the components is omitted. The description of the first embodiment is applied as appropriate to components that are not particularly described in the second embodiment. The cooked food enclosure of the second embodiment is a cooked food enclosure comprising a sealed packaging container and a cooked food enclosed in a storage space in the packaging container, The accommodation space contains oxygen, carbon dioxide, and nitrogen, and the oxygen concentration in the accommodation space is 1% by volume or more and 10% by volume or less.

  In the second embodiment, only the above 4) “the oxygen concentration of the housing space of the packaging container is 1 volume% or more and 10 volume% or less” is essential among the above-described 1) to 4) which are essential constituent elements of the first embodiment. In addition, it is different from the first embodiment in that other requirements are not essential. The cooked food inclusion body according to the second embodiment exhibits an excellent toxin production inhibitory effect against Clostridium microorganisms, in particular, Clostridium botulinum microorganisms. Moreover, as a specific example of the food (cooked food) enclosed in the cooked food inclusion body of the second embodiment, cooked side dishes such as macaroni gratin, hijiki-ni, hamburger, beef stew, chicken teriyaki, etc. Can be mentioned.

The method for producing a cooked food inclusion body of the present invention (a method for preserving cooked food) including the first and second embodiments described above may include, for example, the following steps 1 and 2. The “chilled state” in the following step 2 is as described above.
Step 1: Heat-cooked food is enclosed in a storage space of a sealable packaging container, the storage space contains oxygen, carbon dioxide, and nitrogen, and the oxygen concentration in the storage space is 1% by volume to 10% by volume. Then, the gas in the accommodation space is replaced so as to become (gas replacement step).
Step 2: A step of storing the cooked food sealed in the packaging container in a chilled state after the step 2 (gas replacement step).

  As preparation before implementation of the step 1, a cooked food is prepared. The cooked food is as described above. When boiled foods contain bacteriostatic agents such as organic acid salts, the timing of adding bacteriostatic agents to foods (foodstuffs) is not particularly limited, and is added to various foodstuffs that are ingredients of cooked foods (various May be added during cooking of food ingredients), or may be added during the cooking process of cooked foods (process of cooking various ingredients), and added to cooked foods (after cooking of food ingredients) May be added). In addition, the cooked food to be subjected to the step 1 may be a product immediately after production (immediately after cooking), or after production, cooled or kept warm under aseptic or sterilized conditions for a certain period of time. It may be after storage.

  You may adjust the pH of the heat-cooked food provided to the said process 1 as needed. In general, when the pH of a food product deviates from the preferred pH range for the growth of microorganisms, the storage stability is improved, but the food flavor may be adversely affected. The pH of the cooked food before being subjected to Step 1 (before gas replacement packaging) is preferably 7.5 or less, more preferably 7.2 or less, more preferably from the viewpoint of microbial safety. Preferably it is 6.5 or less, More preferably, it is 6.0 or less, From a viewpoint of flavor, Preferably it is 4.0 or more, More preferably, it is 4.5 or more, More preferably, it is 5.0 or more, More preferably, it is 5 .5 or more, more preferably 6.0 or more. It is desirable that the pH of the cooked food is adjusted within a range that does not impair the flavor according to the type of the food.

  In the step 1 (gas replacement step), the gas replacement can be performed by any one of the methods i) and ii). As an example of the gas replacement method in the step 1, when the cooked food inclusion body of the first embodiment is manufactured, the volume ratio of these three components including oxygen, carbon dioxide, and nitrogen is oxygen: carbon dioxide: nitrogen. = 1 to 10:20 to 50:40 to 79, a mixed gas is prepared, and the mixed gas is replaced with a gas in the storage space into a storage space in the packaging container in which the cooked food is stored. The method of filling so that it may become 95% or more of the rate is mentioned.

  In step 1 (gas replacement step), the cooked food can be enclosed in the packaging container's storage space in accordance with a conventional method. For example, the cooked food and the specific composition are contained in the storage space of the predetermined packaging container. The container may be sealed using a known sealing method such as heat sealing.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not limited only to such an Example.

[Examples 1 to 13, Comparative Examples 1 to 5 and Reference Examples 1 to 4]
As the cooked food, macaroni gratan and mapo tofu (both are side dishes) were produced by the following methods. After filling one kind of prepared sugar beet into the accommodation space of the packaging container (made by PP, accommodation capacity 340 mL), a mixed gas containing at least two kinds of oxygen, carbon dioxide and nitrogen (this example, comparison) In the example or the reference example, the gas in the accommodation space is obtained by a desktop vacuum packaging device V-380G (Tosei Kasei Co., Ltd.) using the mixed gas having the same composition as the gas composition value in the accommodation space of the packaging container. Was replaced with the mixed gas, and the packaging container was sealed to produce the intended cooked food inclusion body.
Put a rubber seal on the surface of the packaged pouch of the prepared food inclusion body obtained in this way, stab an injection needle through the seal, inoculate the surface of the food with a spore solution of Clostridium botulinum type E, And the cooked food inclusion body was manufactured.
On the other hand, for Bacillus and Microbacterium, one kind of prepared sugar beet is filled in the storage space of the packaging container (PP, storage capacity 340 mL), and then each bacterial solution is inoculated into the whole sugar beet. Then, using a mixed gas containing at least two or more of oxygen, carbon dioxide and nitrogen, a fungus-inoculated and cooked food inclusion body was produced.
The bacterially inoculated and cooked food inclusions obtained in this way were stored in a chilled state in an environment with an average temperature of 10 ° C. immediately after production.

The macaroni gratin was manufactured according to a cooking recipe (determined version: basic side dish of Kobayashi cutlet, p.176, issued by Shufu no Tomosha), and ingredients were prepared according to the cooking recipe.
Mapo tofu was produced according to a cooking recipe (delicious basic Chinese food, p.62, published by Seimido Publishing), and ingredients were prepared according to the cooking recipe.
In addition, when using a bacteriostatic agent, regardless of the type of sugar beet, after using sodium acetate as a bacteriostatic agent and adding a predetermined amount of sodium acetate to the food material, the central temperature of the food material is 85 ° C. for 2.5 minutes. The ingredients were cooked so that they were maintained.

〔Evaluation test〕
For the inoculated and cooked food inclusions of each Example and Comparative Example, the gas analyzer (trade name “CheckMate”, manufactured by PBI Dunsensor) is used for the composition of the gas in the packaging container storage space immediately after manufacture. It was measured by a sampling inspection.
Moreover, about the bacteria production inoculated and cooked food inclusion body of each Example and the comparative example, the toxin production inhibitory effect of Clostridium botulinum and the growth inhibitory effect of the bacteria of the genus Bacillus and Microbacterium were evaluated.
Specifically, for evaluating the toxin production inhibitory effect of Clostridium botulinum, after storing for 14 days in a chilled state (10 ° C.), aseptically remove the entire contents of the specimen from a sterile polyethylene bag for stomachers (Eiken Chemical Co., Ltd., Filtrait) In the bag HG-S), 4 times as much sterilized deionized water was added and mixed well with a stomacher to obtain a 5 times emulsion. An equal amount of 2% trypsin solution was mixed with 1.5 mL of this 5-fold emulsion and heated at 37 ° C. for 1 hour. 0.4 mL of this solution was injected into the abdominal cavity of two mice (ddY, clean mouse, 4 weeks old, male). Those that died within 72 hours after injection were positive for toxin, and those that survived were considered toxin negative.
As for the growth inhibitory effect evaluation of Bacillus and Microbacterium, the microorganisms in the prepared foods were added to the inoculated and cooked food inclusion bodies immediately after production and after storage for 14 days in a chilled state (10 ° C). The number of microorganisms after storage for 14 days in the chilled state is 11 og when the number of microorganisms is measured by the following method and the number of microorganisms in the sugar beet immediately after production is defined as the “initial microorganism number”. The following cases were marked with ◯, and the case where the increase number exceeded 11 og was marked with ×.
Moreover, about Examples 11-13 and Reference Examples 3 and 4, the quality of the food enclosed in the uncooked cooked food inclusion body after storage for 14 days in a chilled state (10 ° C.) is evaluated by the following method. did. The above results are shown in Tables 1 to 3 below.

<Method for measuring the number of microorganisms>
The number of microorganisms in the medium in the inclusion bodies was measured immediately after packaging and after storage for 14 days in a chilled state (10 ° C.). The number of microorganisms was measured by the surface smear plate method. Specifically, it went as follows.
The sample solution was prepared by diluting 10 times with a diluent and mixing well. Thereafter, 0.1 mL of the sample solution or 0.1 mL of the sample solution diluted 100-fold or 10000-fold was dropped onto the surface of the medium on which various agar media had been hardened in advance, and the cells were smeared evenly with a congeal bar and cultured. As the medium and culture conditions, aerobic culture at 35 ° C. for 48 hours using a standard agar medium (Eiken Chemical Co., Ltd.) was employed for the measurement of the number of Bacillus and Microbacterium.
The number of microorganisms was counted as the number of microorganisms per gram of medium (cfu / g) by multiplying the number of colonies grown in the medium by the dilution factor. For example, when 30 colonies were observed after culturing in a medium inoculated with 0.1 mL of the sample solution without diluting the sample solution, the concentration was set to 3.0 × 10 ³ cfu / g. The value of the medium that gave the maximum number of microorganisms in the medium for each bacterium was taken as the result of the microorganism count measurement.

<Food quality evaluation method>
Ten panelists ate the food encapsulated in the uncooked cooked food inclusion body, and evaluated it according to the following evaluation criteria (5-point scale). The average of these evaluation points was calculated and used as quality evaluation.
(Evaluation criteria for food quality)
5 points: Very good flavor equivalent to that before storage in a chilled state for 14 days.
4 points: Slightly inferior to pre-storage in a chilled state for 14 days, but good flavor.
3 points: Flavor is inferior compared to before storage in a chilled state for 14 days.
2 points: The flavor is remarkably inferior compared with that before storage in a chilled state for 14 days.
1 point: Flavor is bad and cannot be provided as a product.

  Table 1 summarizes the influence of the oxygen concentration in the housing space of the packaging container on the toxin production inhibitory effect of microorganisms (Botulinum), and relates to the evaluation of the effectiveness of the second embodiment. As shown in Table 1, when the oxygen concentration in the storage space of the packaging container is 0% by volume, the growth of Clostridium botulinum may not be suppressed depending on the type of food (Comparative Example 2). On the other hand, the toxin production of Clostridium botulinum can be effectively suppressed by setting the oxygen concentration in the accommodation space of the packaging container to 1% by volume or more as in each example.

  Table 2 mainly relates to the evaluation of the effectiveness of the first embodiment. In Table 2, each example is divided into three groups I to III. Group I is an example in which the carbon dioxide concentration in the housing space of the packaging container is appropriately changed, and Group II is a cooked food. This is an example in which the content of the bacteriostatic agent is appropriately changed, and Group III is an example in which the food storage space occupation ratio is appropriately changed. As shown in Table 2, in order to suppress the growth of microorganisms belonging to the genus Bacillus and Microbacterium, the concentration of carbon dioxide in the storage space of the packaging container is 20 to 40% by volume, and the bacteriostatic agent in the cooked food It can be seen that it is effective to set the content of 0.1 to 0.25% by mass and the food storage space occupancy to 30 to 70% by mass. On the other hand, for Clostridium botulinum, if the oxygen concentration in the storage space of the packaging container is 7% by volume, the toxin production is suppressed regardless of the carbon dioxide concentration, the bacteriostatic agent, and the food space occupation rate. I understand that I can do it.

Claims (9)

A cooked food enclosure comprising a sealed packaging container and a cooked food sealed in a storage space in the packaging container,
A cooked food enclosure in which the accommodation space contains oxygen, carbon dioxide, and nitrogen, and the oxygen concentration of the accommodation space is 1% by volume or more and 10% by volume or less. A cooked food enclosure comprising a sealed packaging container and a cooked food sealed in a storage space in the packaging container,
The storage space contains oxygen, carbon dioxide, and nitrogen, and the oxygen concentration in the storage space is 1% by volume to 10% by volume, and the carbon dioxide concentration is 20% by volume to 50% by volume,
The cooked food contains a bacteriostatic agent,
The cooked food inclusion body in which the ratio of the volume of the cooked food to the volume of the accommodation space is 20 to 80%.   The cooked food inclusion body according to claim 2, wherein the bacteriostatic agent is an organic acid salt.   The cooked food inclusion body according to claim 3, wherein the content of the organic acid salt in the cooked food is 0.1 to 1.0% by mass.   The cooked food inclusion body according to claim 3 or 4, wherein the organic acid salt is sodium acetate.   The cooked food inclusion body according to any one of claims 1 to 5, wherein the cooked food is a food that has been heated for 1 minute or more under a condition such that the center temperature is 75 to 90 ° C.   The cooking according to any one of claims 1 to 6, wherein the housing space is divided into a plurality of small spaces, and one or more of the cooked foods are arranged in each of the small spaces. Finished food inclusions. Heat-cooked food is enclosed in a storage space of a sealable packaging container so that the storage space contains oxygen, carbon dioxide, and nitrogen, and the oxygen concentration in the storage space is 1% by volume to 10% by volume. A gas replacement step of replacing the gas in the accommodation space;
After the gas replacement step, the cooked food storage method includes a step of storing the cooked food sealed in the packaging container together with the packaging container in a chilled state.   In the gas replacement step, a mixed gas containing oxygen, carbon dioxide and nitrogen and having a mixing volume ratio of these three components in the range of oxygen: carbon dioxide: nitrogen = 1 to 10:20 to 50:40 to 79, The method for preserving cooked food according to claim 8, wherein filling is performed so that the gas replacement rate of the accommodation space is 95% or more.