Packaged radish salad and method for maintaining freshness

Abstract

To provide a technique capable of effectively keeping freshness of radish salad.SOLUTION: A freshness-keeping packaging container according to the present invention is a radish salad container that is constituted of a resin film and satisfies the following requirement 1. (Requirement 1) 125 grams of salad containing 55 to 70 mass% of cut radish, that is obtained by the following procedure is stored in the freshness-keeping packaging container, hermetically packaged, and then, preserved at 10°C for 48 hours. A difference (Δb*) of b* value is 5 or less in CIE1976-L*a*b* colorimetric system of the cut radish between immediately after the hermetic packaging and at a time when preserved at 10°C for 48 hour. Procedure: A raw Japanese white radish is washed. Then, part excluding leaves and skins of the radish is cut into a length of 50 to 65 mm and a thickness of 2 to 3 mm. and then, subjected to a germicidal treatment using 100 ppm of a sodium hypochlorite solution, dewatered so that the cut radish is obtained.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a freshness - retaining packaging container, a packaging bag, and a freshness - retaining method. More specifically, it relates to a freshness - retaining packaging container for daikon radish salad, a packaged product containing daikon radish salad, and a method for retaining the freshness of daikon radish salad.

Background Art

[0002] Cut vegetables are in increasing demand among consumers because they can be eaten without washing and can be used in small packages. On the other hand, since the freshness of vegetables starts to decline after harvest, how to maintain freshness has become a major issue. In particular, cut vegetables tend to deteriorate rapidly, and even higher freshness - retaining technologies are required.

[0003] For example, Patent Document 1 discloses a technique for maintaining the freshness of cut vegetables without using chlorine - based bactericides such as sodium hypochlorite, which have been conventionally used for sterilizing vegetables. Specifically, cut vegetables are treated with water added with at least one of calcium hydroxide and calcium oxide, washed with water, then stored in a packaging container, and while maintaining the oxygen concentration in the packaging container within the range of 5 - 10% by volume and the carbon dioxide concentration within the range of 10 - 15% by volume, they are stored at a low temperature of - 1°C to 3°C.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the technique described in Patent Document 1 still had room for further improvement in the freshness - retaining effect on daikon radish salad. The inventors of the present invention have diligently studied a new packaging container for maintaining the freshness of daikon radish salad and have found that controlling the cutting of a predetermined daikon radish to satisfy desired discoloration parameters is effective in maintaining the freshness of daikon radish salad at a high level and stably. [Means for solving the problem]

[0006] The present invention is a freshness-preserving packaging container for radish salad made of resin film, To provide a freshness-preserving packaging container that satisfies the following requirement 1. (Requirement 1) Place 125g of salad containing 55-70% by mass of the cut daikon obtained by the following procedure into the freshness-preserving packaging container, seal it, and store it at 10°C for 48 hours. The CIE1976-L of the cut daikon is measured immediately after sealing and after being stored at 10°C for 48 hours. * a * b * b in the color system * Difference in values ​​(Δb) * ) is 5 or less. Procedure: Wash the raw Aokubi daikon radish. Next, cut the parts of the Aokubi daikon radish excluding the leaves and peel into pieces 50-65 mm long and 2-3 mm thick. Sterilize them with a 100 ppm sodium hypochlorite solution, dehydrate them, and obtain cut daikon.

[0007] Furthermore, the present invention provides a package containing daikon salad, in which daikon salad is packaged using the freshness-preserving packaging container described above.

[0008] Furthermore, the present invention provides a method for preserving the freshness of daikon radish salad by packaging the salad using the above-mentioned freshness-preserving packaging container. [Effects of the Invention]

[0009] According to the present invention, a technology is available that can effectively maintain the freshness of daikon radish salad. [Modes for carrying out the invention]

[0010] Hereinafter, embodiments of the present invention will be described.

[0011] <Freshness retention container> The freshness retention packaging container of this embodiment is composed of a resin film and is for daikon salad, satisfying the following requirement 1. As a result, the freshness of daikon salad can be effectively and stably improved.

[0012] (Requirement 1) After accommodating 125 g of salad containing 55 to 70% by mass of cut daikon obtained by the following procedure in the freshness retention packaging container and sealing it, store it at 10°C for 48 hours. The CIE1976-L * a * b * b value in the colorimetric system * difference (Δb * ) is 5 or less. Procedure: Wash raw green-top daikon radish. Next, cut the part excluding the leaves and skin of the green-top daikon radish into pieces with a length of 50 to 65 mm and a thickness of 2 to 3 mm, then perform a sterilization treatment using a 100 ppm sodium hypochlorite solution, dehydrate it, and obtain cut daikon.

[0013] In the above procedure of Requirement 1, it is preferable that the raw green-top daikon radish is within 4 days after harvest. The raw state means a state without undergoing cooking such as heat treatment or salting. It is desirable that the daikon is in a fresher state. Washing is performed to remove soil and the like adhering to the green-top daikon radish. It is preferably performed with running water, and in order to enhance the washing effect, water may be sprayed or a brush may be used. The washing time and the amount of water are appropriately adjusted according to the amount and state of the soil adhering to the green-top daikon radish. Also, after washing with water, if necessary, a detergent using a neutral detergent may be performed. Thereby, the microorganisms adhering to the green-top daikon radish can be further reduced.

[0014] Furthermore, in the above procedure, the green-necked radish is cut using a known method. When cutting, the leaves and peel may be removed beforehand. After cutting, it may be soaked in water or similar to maintain freshness or remove foreign matter. The length and thickness of the cut radish are average values. Subsequently, the vegetables are sterilized using a 100 ppm sodium hypochlorite solution and then dehydrated. The sterilization and dehydration methods can be those known for use in pre-cut vegetables. The moisture content of cut daikon radish immediately after sealing is preferably 20-60%, and more preferably 25-55%.

[0015] The series of operations in this procedure should be carried out quickly to avoid degrading the freshness of the radish. Furthermore, the working environment temperature should preferably be lower than room temperature, more preferably between 4°C and 15°C. The water temperature should be below the temperature of tap water.

[0016] Furthermore, in Requirement 1, a salad containing 55-70% by mass of cut daikon radish also includes other vegetables that are eaten as is in a salad. Examples of such vegetables include those that add color to the daikon salad to improve its appearance, and those that enhance the taste and flavor of the daikon salad. Specifically, vegetables that are mainly eaten uncooked are preferred, and examples include one or more types selected from lettuce varieties (lettuce, leaf lettuce, romaine lettuce, red leaf lettuce, salad lettuce, ssamjang, etc.), cabbage, carrots, radishes, kale, celery, spinach, komatsuna, mizuna, cucumbers, onions, bell peppers, paprika, endive, and radicchio, as well as cut versions of these vegetables.

[0017] In Requirement 1, known methods may be used for sealing, but heat sealing is preferred from the viewpoint of obtaining a good appearance, convenience, and airtightness. Furthermore, the size of the freshness-preserving packaging container is not particularly limited; it should be a suitable size, neither too large nor too small, for packaging 125g of salad. It is also preferable that it has so-called dead space to prevent the salad from being crushed by external stress.

[0018] In this embodiment, the CIE1976-L of the radish immediately before and after the predetermined storage as shown in Requirement 1. * a * b * b in the color system * Difference in values ​​(Δb) * ) is 5 or less. Here, L * a * b * In color systems, a * The value represents the intensity of the color from green to red, with 0 as the axis, where negative values ​​represent green and positive values ​​represent red. * The value represents the intensity of the color from blue to yellow, with 0 as the axis, where negative values ​​represent blue and positive values ​​represent yellow. * The value is a parameter from 0 to 100 that indicates brightness, L * A value of 100 represents white, L * A value of 0 represents black. Note L * a * b * The values ​​are measured in accordance with JIS K 5600 4-4 to 4-6.

[0019] The freshness-preserving packaging container of this embodiment focuses on the variation in the yellowness of radishes and measures the (Δb) before and after storage. * The smaller the (Δb), the less variation in the yellowness of the radish, i.e., browning, is intended. Therefore, in the freshness-preserving packaging container of this embodiment, the (Δb * By keeping the (Δb) below 5, the freshness of the radish salad can be maintained at a high level. * The ratio is preferably 4.8 or less, more preferably 4.5 or less, even more preferably 4.2 or less, even more preferably 4.0 or less, and even more preferably 3.8 or less.

[0020] Furthermore, in Requirement 1, the CIE1976-L of the radish immediately before and after storage. * a * b * L in the color system * Difference in values ​​(ΔL) * It is preferable that the value is ±0.8 or less. In other words, the freshness-preserving packaging container of this embodiment focuses on the variation in the whiteness of radishes and the (ΔL) before and after storage. * The smaller the (ΔL), the smaller the variation in the whiteness of the radish. Therefore, in the freshness-preserving packaging container of this embodiment, the (ΔL) is intended to be. * By keeping the (ΔL) below ±0.8, the freshness of the radish salad can be maintained at a high level. * The value is preferably ±0.7 or less, more preferably ±0.6 or less, even more preferably ±0.5 or less, and most preferably ±0.4 or less.

[0021] In the freshness-preserving packaging container of this embodiment, such L * a * b * The desired value can be achieved by adjusting and combining the constituent materials, properties such as air permeability, and thickness of the resin film that makes up the freshness-preserving packaging container.

[0022] Furthermore, in requirement 1, it is preferable that the oxygen concentration inside the freshness-preserving packaging container after 48 hours of storage at 10°C be 0.5% or less, more preferably 0.4% or less, and even more preferably 0.3% or less. This suppresses the respiration of the cut radish and makes it easier to suppress browning. On the other hand, the oxygen concentration inside the freshness-preserving packaging container after 48 hours of storage at 10°C is preferably 0.01% or higher, and more preferably 0.05% or higher. This suppresses the generation of odors due to anaerobic respiration caused by insufficient oxygen.

[0023] Furthermore, in requirement 1, it is preferable that the carbon dioxide concentration in the freshness-preserving packaging container after 48 hours of storage at 10°C be within the range of 2.0 to 4.0%, more preferably within the range of 2.5 to 3.8%, and even more preferably within the range of 2.7 to 3.6%. This appropriately maintains the respiration of the cut radish and ensures a stable freshness-preserving effect.

[0024] [Resin film] The freshness-preserving container of this embodiment is made of a resin film. This allows for adequate respiration of the radish salad while achieving the MA effect. It also suppresses odors and helps maintain the good appearance of the radish.

[0025] The resin film is preferably transparent or semi-transparent, and more preferably transparent, from the viewpoint of allowing the radish salad to be visible from the outside. It may also be printed with information for purposes such as identifying the radish salad.

[0026] The resin used to make up the resin film is not particularly limited as long as it can be used for packaging radish salad; any known resin can be used. For example, the resin film is preferably one or more selected from the group consisting of polyethylene, ethylene copolymers such as ethylene-vinyl alcohol copolymer, polyester resins such as polypropylene, polyvinyl chloride, polystyrene, (meth)acrylic resin, and polylactic acid, and polyamide resins such as nylon. In particular, from the viewpoint of appropriately controlling the water vapor permeability and oxygen permeability described later, polyethylene, ethylene-vinyl alcohol copolymer, polypropylene, polylactic acid, and nylon are preferred, and from the viewpoint of increasing the biomass content, it is more preferable to include polyethylene and polypropylene, and even more preferable to include polypropylene.

[0027] The resin film of this embodiment preferably has a biomass content of 5% or more, and more preferably 10% or more. This makes it possible to improve the trade-off balance between the deterioration of the resin film's performance and its freshness preservation effect while reducing the environmental burden. Biomass resin films are realized by using biomass resins synthesized using biomass raw materials instead of crude oil. For example, a biomass polypropylene film can be obtained by synthesizing biomass polypropylene from biomass raw materials, polymerizing it, and then molding a film using the resulting bio-polypropylene resin. In this embodiment, the biomass content of the resin film is determined from the amount of biomass polymer (e.g., polypropylene) blended in the resin film. For example, in the case of a resin film obtained using polyethylene and polypropylene, a resin film with a biomass content of 5% can be obtained by including 5% biomass polypropylene.

[0028] The method for forming the resin film is not particularly limited, but methods such as extrusion, inflation, and calendering can be used. When forming the resin film, additives such as antifogging agents may be mixed in as needed, and two or more types of resin may be blended. Furthermore, the resin film may be subjected to stretching or annealing, and a sealant layer may be provided to give it heat-sealing properties. In particular, stretched films that have undergone stretching treatment are preferred. This improves the rigidity, pinhole resistance, water vapor and oxygen barrier properties, and appearance of the resin film. For example, stretched nylon film, stretched polylactic acid film, stretched polyethylene and polypropylene mixture film, and stretched polypropylene film are preferred.

[0029] The thickness of the resin film is preferably 15 to 50 μm, more preferably 20 to 40 μm, and even more preferably 23 to 35 μm.

[0030] The resin film may be used as a single layer or as a multilayer structure of two or more layers.

[0031] The oxygen permeability of the resin film at 23°C and 60% RH is preferably 200 cc / (m²) from the viewpoint of maintaining the respiration and freshness of cut vegetables. 2 (day·atm) or more, more preferably 500cc / (m 2 (day·atm) or more, and even better is 800cc / (m 2 (day·atm) or more, and especially preferably 1000cc / (m 2 (This is the total value for days and hours.) On the other hand, the oxygen permeability of the resin film at 23°C and 60% RH is preferably 10,000 cc / (m²) from the viewpoint of maintaining the quality and freshness of cut vegetables. 2 (day·atm) or less, more preferably 7000cc / (m 2 It is less than or equal to (day·atm), and more preferably 4000cc / (m 2 It is less than or equal to (day·atm), and more preferably 3000cc / (m 2 (•day•atm) is less than or equal to the following:

[0032] The water vapor permeability of the resin film at 40°C is preferably 1 g / (m²) from the viewpoint of releasing water vapor due to the respiration of cut vegetables. 2 (day) or more, more preferably 3g / (m 2 • day) or more, and more preferably 5 g / (m 2 It is more than (day) On the other hand, the water vapor permeability of the resin film at 40°C is preferably 300 g / (m²) from the viewpoint of suppressing the respiration of cut vegetables. 2 • day) or less, more preferably 100g / (m 2 It is less than or equal to (day), and more preferably 80 g / (m 2 • day) or less, and more preferably 20 g / (m 2 It is less than or equal to (day).

[0033] Water vapor transmission can be measured using a method compliant with JIS Z 0208 (Cup method).

[0034] Furthermore, in this embodiment, the oxygen permeability and water vapor permeability of the resin film can be adjusted by controlling the selection of the resin film material, the manufacturing method of the resin film, the layer structure of the resin film, the presence or absence of through holes, and the average diameter and number of through holes.

[0035] [Application] The daikon salad of this embodiment is made by cutting the daikon into bite-sized pieces and is intended to be eaten uncooked with seasonings such as dressing according to the consumer's preference. For cutting, known methods such as julienne or slicing can be used. The variety of daikon radish used in the daikon salad is not particularly limited, but it is preferable to use the Aokubi daikon, which is commonly used in salads.

[0036] The radish salad may contain other vegetables, but the proportion of radish should be 50% by mass or more, preferably 55% by mass or more, more preferably 60% by mass or more, and even more preferably 65% ​​by mass or more.

[0037] Other vegetables are not particularly limited and include those similar to those eaten as is in a salad as described in Requirement 1 of the packaging container. It is also preferable that the other vegetables are cut into easy-to-eat pieces.

[0038] [Container shape] Examples of container forms include bags, sheets, self-standing containers, self-standing containers with lids, or lids for self-standing containers. Among these, bags and self-standing containers are preferred, and bags are more preferred, as they can stably maintain freshness. When the freshness-preserving packaging container is in the form of a bag, its size can be set as appropriate, but from the viewpoint of ease of handling when sold as daikon salad and ensuring that the contents are consumed relatively quickly after opening, a side length of 100 to 300 mm is preferable.

[0039] [Through hole] Freshness-preserving packaging containers may or may not have through-holes. The presence or absence of through-holes allows for stable adjustment of water vapor and oxygen permeability.

[0040] The planar shape of the through-hole may be, for example, circular, polygonal, or a slit. Circular is not limited to a perfect circle, but includes approximately circular shapes. In addition to circular shapes, semicircular or crescent shapes are also acceptable. A polygon is any shape enclosed by three or more line segments, such as a triangle, quadrilateral, or pentagon. A slit is a cut or narrow gap that penetrates the synthetic resin sheet constituting the packaging material, and may be a straight line, curve, L-shaped, or X-shaped, with no particular limitations on its length.

[0041] The average diameter of the through-holes is preferably 10 μm to 800 μm, more preferably 20 μm to 500 μm, and even more preferably 50 μm to 200 μm. Setting the average diameter above the lower limit improves water vapor and oxygen permeability, making it easier to maintain freshness by suppressing mold growth. On the other hand, setting the average diameter below the upper limit prevents the entry of foreign matter and suppresses wilting of the radish salad. The average diameter of the through-hole is calculated by assuming the through-hole is a perfect circle, based on the area of ​​the opening.

[0042] The above-mentioned through holes may be formed in the resin film in advance when manufacturing the freshness-preserving container, may be formed after the resin film has been formed into a container shape, or may be formed before or after the resin film has been formed into a container shape.

[0043] <Package> The packaging of this embodiment is a package containing daikon salad, in which the daikon salad is packaged in the freshness-preserving packaging container described above. In this embodiment, the inner surface area of ​​the packaging per 125g of daikon salad is 100 to 5000 cm². 2 Preferably, it is 200-1000cm 2 More preferably, 250-800cm 2 More preferably, 300-600cm 2 This is especially preferable. This allows for an even higher level of preservation of the freshness of the radish salad.

[0044] Furthermore, the weight retention rate of the packaging in this embodiment is preferably 95% or more, more preferably 97% or more, and even more preferably 98% or more. By setting it to such a value, the freshness of the radish salad can be maintained more stably. The weight retention rate refers to the percentage (%) of the weight (g) of the daikon salad that is retained before and after being sealed in the freshness-preserving packaging container described above and stored at 10°C for 48 hours. The retention of the daikon salad's weight means that its freshness is preserved.

[0045] <Methods for maintaining freshness> The method for preserving the freshness of the daikon salad in this embodiment is to package the daikon salad using the freshness-preserving packaging container described above. After packaging, it is preferable that the opening of the container be sealed. The above sealing can be achieved, for example, by heat-sealing the opening of a bag, or by using materials such as back sealing tape, cable ties, rubber bands, or rivets. Alternatively, if the container is the lid of a self-standing container, the cut vegetables may be placed inside the self-standing container, and the lid may be closed after gas replacement. It is preferable that the lid be closed by heat sealing. Furthermore, sealing helps to maintain the freshness of the cut vegetables from the time they are packaged until they are distributed and consumed by consumers.

[0046] Furthermore, in this embodiment, the package containing the daikon salad is preferably stored at an ambient temperature of 2 to 10°C. That is, it is preferable that it be stored at 2 to 10°C after packaging and sealing, and while it is on display in stores. However, temperature fluctuations are acceptable depending on the intended use, distribution conditions, etc.

[0047] The embodiments of the present invention have been described above, but these are merely examples, and various other configurations can also be adopted. Examples of reference formats are provided below. 1. A freshness-preserving packaging container for radish salad made of resin film, A freshness-preserving packaging container that meets the following requirement 1. (Requirement 1) Place 125g of salad containing 55-70% by mass of the cut daikon obtained by the following procedure into the freshness-preserving packaging container, seal it, and store it at 10°C for 48 hours. The CIE1976-L of the cut daikon is measured immediately after sealing and after being stored at 10°C for 48 hours. * a * b * b in the color system * Difference in values ​​(Δb) * ) is 5 or less. Procedure: Wash the raw Aokubi daikon radish. Next, cut the parts of the Aokubi daikon radish excluding the leaves and peel into pieces 50-65 mm long and 2-3 mm thick. Sterilize them with a 100 ppm sodium hypochlorite solution, dehydrate them, and obtain cut daikon. 2. The freshness-preserving packaging container described in 1. A freshness-preserving packaging container in which the oxygen concentration inside the freshness-preserving packaging container is 0.5% or less after being stored at 10°C for 48 hours, as described in Requirement 1 above. 3. A freshness-preserving packaging container as described in 1. or 2., In requirement 1 above, the CIE1976-L of the cut radish immediately after sealing and after being stored at 10°C for 48 hours. * a * b * L in the color system * Difference in values ​​(ΔL) * A freshness-preserving packaging container in which the tolerance is ±0.8 or less. 4. A freshness-preserving packaging container described in any one of items 1 to 3, The oxygen permeability of the aforementioned resin film at 23°C and 60% RH is 200 to 10000 cc / (m²). 2 A freshness-preserving packaging container that is less than or equal to (day / atm). 5. A freshness-preserving packaging container described in any one of items 1 to 4, The water vapor permeability of the aforementioned resin film at 40°C is 1 to 400 g / m². 2 A freshness-preserving packaging container (for use on days). 6. A freshness-preserving packaging container described in any one of items 1 to 5, The aforementioned resin film is a freshness-preserving packaging container having a biomass content of 5% or more. 7. A freshness-preserving packaging container described in any one of items 1 through 6, The aforementioned resin film is a freshness-preserving packaging container having a biomass content of 10% or more. 8. A freshness-preserving packaging container described in any one of items 1 through 7, The resin film is one or more selected from the group consisting of polyethylene, ethylene copolymer, polypropylene, polyvinyl chloride, polystyrene, (meth)acrylic resin, polyester resin, and polyamide resin, in a freshness-preserving packaging container. 9. A freshness-preserving packaging container described in any one of items 1 through 8, A freshness-preserving packaging container in which the resin film has a thickness of 15 to 50 μm. 10. A freshness-preserving packaging container described in any one of items 1 through 9, The aforementioned resin film is a stretched film, used as a freshness-preserving packaging container. 11. A freshness-preserving packaging container described in any one of items 1 to 10, The freshness-preserving packaging container is a bag-shaped freshness-preserving packaging container. 12. A freshness-preserving packaging container described in any one of items 1 to 11, The freshness-preserving packaging container is a freshness-preserving packaging container that does not have through holes. 13. A package containing daikon salad, in which the daikon salad is packaged in a freshness-preserving packaging container as described in any one of items 1 through 12. 14. The packaging described in 13. The inner surface area of ​​the packaging for 125g of the aforementioned radish salad is 100cm². 2 More than 5000cm 2 The following is the packaging. 15. A method for preserving the freshness of daikon salad, comprising packaging the daikon salad using a freshness-preserving packaging container described in any one of items 1 to 12. 16. The method for maintaining the freshness of the radish salad described in 15. A method for maintaining the freshness of daikon salad when stored at an ambient temperature of 2-10°C. [Examples]

[0048] Next, the present invention will be described in detail with reference to examples, but the content of the present invention is not limited to these examples.

[0049] <Measurement> ·L * a * b * Measurement of Values Measurements were taken using a Konica Minolta CM-600d spectrophotometer, in accordance with JIS K 5600 4-4 to 4-6. The light source was a pulsed xenon lamp with a wavelength of 400-700 nm. Furthermore, the measurements were taken only from the cut radishes inside the packaging bags.

[0050] • Measurement of moisture content The moisture content of cut daikon radish was determined using a universal moisture meter "HB-300" manufactured by Kett Scientific Co., Ltd. Electrodes were inserted through the opening of the packaging bag and brought into contact with the cut daikon radish. Current was then applied to measure the moisture content (%). Measurements were taken at five locations per packaging bag, and measurements were taken for two packaging bags. The average value was then calculated.

[0051] • Measurement of gas concentration: Oxygen and carbon dioxide concentrations were measured using a Check Point O2 / CO2 device manufactured by MOCON Europe.

[0052] • Water vapor transmission rate at 40°C (g / m³) 2 Measurement (day) Measurements were taken in accordance with JIS Z 0208 (cup method).

[0053] Oxygen permeability at 23°C and 60% RH (cc / m³) 2 Measurement of ·day·atm) (1) Nitrogen gas filling After sealing the bags using heat sealing or similar methods, the bags were degassed using an aspirator or similar device. Degassing was continued until both sides of the bag were stuck together. Next, nitrogen gas (purity 99.9% or higher) was filled into the bags using a white hard syringe. The amount of nitrogen gas injected was adjusted to the size of the bag, and as much as possible was injected while ensuring that the film constituting the bag was not under tension due to the injected nitrogen gas, but was slightly loose. The amount was measured using the scale on the white hard syringe. Nitrogen gas degassing and injection were performed, for example, by piercing the bag with a needle. When piercing with a needle, double-sided tape was applied to the film constituting the bag, and then polypropylene film adhesive tape (hereinafter referred to as "PP tape") was applied on top of that. After removing the needle, the needle hole was quickly sealed with PP tape. The tape applied to the bag was kept to an area of ​​4.5 cm² or less. Furthermore, if the film constituting the bag is a microporous film, the tape was not used to block the micropores. (2) Measurement of initial oxygen concentration The initial oxygen concentration (C0) inside the bag immediately after filling with nitrogen gas (t=0) was measured. The gas inside the bag was sampled, and the initial oxygen concentration (C0) inside the bag was determined by gas chromatography (TCD). C0 was 0.2% or less; if it exceeded this, the procedure was repeated. The sampled gas for oxygen concentration measurement was 10cc or less. When injecting into the gas chromatograph, a constant amount of approximately 1cc was injected. In addition, measurements of standard gases (two or more points containing approximately 1% and 10% oxygen) were also performed by injecting the same amount of gas, and a calibration curve was created. (3) Storage of the bag The bags used for initial oxygen concentration measurement were stored at 23°C and 60% RH (in a temperature- and humidity-controlled cabinet). During this time, the bags were left undisturbed so that no objects were placed on top of them and the cabinet's fan did not directly blow air onto them. (4) Measurement of oxygen concentration inside the bag during storage and calculation of oxygen permeation rate The oxygen concentration inside the bag was measured at a total of 3 to 5 points, with at least two measurements taken immediately after nitrogen gas filling and again at least 3 hours later, within the range of 1% to 7%. A proportional relationship (correlation coefficient of 0.98 or higher) must be established between the elapsed time t (hr) and the oxygen concentration inside the bag. If the correlation coefficient was not established, the test was repeated. If the oxygen permeability rate of the film constituting the bag was too high, causing the oxygen concentration inside the bag to rise too quickly and failing to meet this condition, a bag could be created by laminating a portion of the film with a known oxygen permeability rate smaller than that of the film being measured, and then the same procedure was followed. In this case, the surface area of ​​the bag was the portion laminated with the other known film. Excluding the known oxygen permeability rate, the oxygen permeability rate of the measured film was calculated by subtracting the oxygen permeability rate of the known film portion from the calculated oxygen permeability rate. The oxygen permeation rate was calculated using the value obtained over the longer elapsed time, as shown in formula (i) below. F = 1.143 × (Ct - C0) × V / t (i) F: Oxygen permeation rate (cc / bag day atm) Ct: Oxygen concentration inside the bag t hours after nitrogen gas filling (%) C0: Oxygen concentration inside the bag immediately after filling with nitrogen gas (%) V: Amount of nitrogen gas filled (cc) t: Time elapsed since gas filling (hr)

[0054] <Examples, Comparative Examples> (1) Bags were prepared using the resin films shown in Table 1 by known methods, and freshness-preserving packaging bags of the sizes shown in Table 1 were prepared. Experiments were also conducted regarding requirements 1 and 2 of these freshness-preserving packaging bags. (2) First, the raw Aokubi daikon radish was washed. Next, the parts of the Aokubi daikon radish excluding the leaves and peel were cut to an average length of 50-65 mm and an average thickness of 2-3 mm. Then, the parts were sterilized with a 100 ppm sodium hypochlorite solution, dehydrated, and cut daikon radish was obtained. The moisture content and weight ratio of the cut daikon radish are as shown in Table 1. (3) Separately, other vegetables were prepared, including carrots, lettuce, bell peppers, mizuna, red bell peppers, and purple cabbage. The carrots were cut into pieces with an average length of 50-65 mm and an average thickness of 2-3 mm, excluding the leaves and peel, similar to the radishes, and then sterilized with a 100 ppm sodium hypochlorite solution and dehydrated. The edible parts of the lettuce, red cabbage, and red bell peppers were cut into pieces with an average length of 50-65 mm and an average thickness of 2-3 mm, and then sterilized with a 100 ppm sodium hypochlorite solution and dehydrated. The mizuna was cut into pieces with an average length of 50-65 mm, sterilized with a 100 ppm sodium hypochlorite solution and dehydrated. (4) 125g of salad containing cut daikon radish and other vegetables in the weight ratios shown in Table 1 was placed in each freshness-preserving packaging bag and sealed by heat sealing. It was then stored at 10°C for 48 hours. (5) The cut radish immediately after sealing and after 48 hours at 10°C according to CIE1976-L * a * b * L in the color system * a * value b * The values ​​were measured and the difference (Δ) between them was calculated. In addition, the oxygen concentration and carbon dioxide concentration inside the packaging bag were measured after 48 hours at 10°C. Four packaging bags were prepared for each sample, and the average value was taken for each sample. The results are shown in Table 1.

[0055] <Reference example> Except for cutting the parts of the Aokubi daikon radish described in (2) above, excluding the leaves and peel, to an average length of 110-130 mm and an average thickness of 0.8-1.2 mm, cut daikon was obtained in the same manner as in the example. Then, 125 g of salad, with the cut daikon making up 100% by weight, was placed in each freshness-preserving packaging bag and sealed by heat sealing. After that, it was stored at 10°C for 48 hours. Subsequently, the measurement described in (5) above was performed. The results are shown in Table 1.

[0056] <Rating> The discoloration and odor of the cut radishes, obtained above after being stored at 10°C for 48 hours, were evaluated (discoloration, odor) by multiple expert technicians.

[0057] [discoloration] A specialist technician visually observed the degree of discoloration of the cut radish under daylight-colored lighting or natural sunlight and evaluated it according to the following criteria. 4: Very good (no browning or discoloration of the radish) 3: Good 2: Slightly deteriorated 1: Severe deterioration

[0058] [Odor] The packaging bag was opened, and a 15cm intake-side silicone tube of the "XP-329m" odor sensor, manufactured by Shiro Sangyo Co., Ltd., was inserted into the bag. The value was measured 30 seconds after insertion. In addition, three expert technicians smelled the contents of the packaging bag to determine whether or not there was an unusual odor. The results obtained were evaluated according to the following criteria. 4: Good (Odor sensor reading is less than 600, and none of the three people detected any unusual odor) 3: Slightly deteriorated (odor sensor reading is less than 600, and one person detects an unusual odor) 2: Obvious deterioration (odor sensor reading is 600 or higher, and two people detect an unusual odor) 1: Severe deterioration (odor sensor reading is 600 or higher, and 3 people detect an unusual odor)

[0059] Table 1

Claims

1. A package containing daikon salad, in which daikon salad is packaged in a freshness-preserving packaging container made of resin film, The inner surface area of ​​the packaging for 125g of the radish salad is 200 to 1000 cm². The freshness-preserving packaging container has an oxygen permeability of 200 to 3000 cc / (m²) of the resin film at 23°C and 60% RH. ２ A package containing daikon salad, which is a day-atm product and satisfies requirement 1 below, and in requirement 1, the oxygen concentration inside the freshness-preserving packaging container after being stored at 10°C for 48 hours is 0.5% or less. (Requirement 1) Place 125 g of salad containing 55-70% by mass of the cut daikon obtained by the following procedure into the freshness-preserving packaging container, seal it, and store it at 10°C for 48 hours. The CIE1976-L of the cut daikon immediately after sealing and after being stored at 10°C for 48 hours. ＊ a ＊ b ＊ b in the color system ＊ Difference in values ​​(Δb) ＊ ) is 5 or less. Procedure: Wash the raw Aokubi daikon radish. Next, cut the parts of the Aokubi daikon radish excluding the leaves and peel into pieces 50-65 mm long and 2-3 mm thick. Sterilize them with a 100 ppm sodium hypochlorite solution, dehydrate them, and obtain cut daikon.

2. A package containing daikon salad according to claim 1, In the above requirement 1, the difference (ΔL ＊ a ＊ b ＊ value) in the L ＊ value in the CIELAB color space between immediately after the hermetic packaging and after storing at 10°C for 48 hours is ±0.8 or less. A packaged product containing daikon radish salad. ＊ )が、±0.8以下である、ダイコンサラダ入り包装体。

3. A package containing daikon salad according to claim 1 or 2, The water vapor permeability of the resin film at 40°C is 1 to 400 g / m². ２ A package containing daikon salad (day).

4. A package containing daikon salad according to any one of claims 1 to 3, The aforementioned resin film is a package containing radish salad, with a biomass content of 5% or more.

5. A package containing daikon salad according to any one of claims 1 to 4, The aforementioned resin film has a biomass content of 10% or more and is used as packaging for radish salad.

6. A package containing daikon salad according to any one of claims 1 to 5, The aforementioned resin film is one or more selected from the group consisting of polyethylene, ethylene copolymer, polypropylene, polyvinyl chloride, polystyrene, (meth)acrylic resin, polyester resin, and polyamide resin, and is used to package a radish salad.

7. A package containing daikon salad according to any one of claims 1 to 6, The aforementioned resin film has a thickness of 15 to 50 μm, and is packaged with radish salad.

8. A package containing daikon salad according to any one of claims 1 to 7, The aforementioned resin film is a stretched film, used in packaging for radish salad.

9. A package containing daikon salad according to any one of claims 1 to 8, The aforementioned freshness-preserving packaging container is a bag-shaped package containing daikon salad.

10. A package containing daikon salad according to any one of claims 1 to 9, The aforementioned freshness-preserving packaging container is a package containing daikon salad and does not have through holes.

11. A package containing daikon salad according to any one of claims 1 to 10, A package containing daikon salad, wherein the proportion of daikon contained in the daikon salad is 50% by mass or more and 69.4% by mass or less.

12. A method for preserving the freshness of daikon salad, comprising storing the packaged daikon salad according to any one of claims 1 to 11 at an ambient temperature of 2 to 10°C.

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