JP2016113172A - Food packaging sheet, food packaging bag, and food package - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a food packaging sheet and a food packaging bag capable of preventing discoloration of a food.SOLUTION: A food packaging sheet to be used for packaging a food comprises a laminate having a first layer, and a second layer to be the most internal layer. The food packaging sheet is such that: a thickness of the second layer is 3 μm-30 μm; and an oxygen permeation degree of the laminate is 20 cc/m2×day×atm-250 cc/m2×day×atm (23°C, 90%RH). The first layer contains preferably a polyester resin or a polyamide resin, and a thickness of the laminate is preferably 40 μm or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a food packaging sheet, a food packaging bag, and a food packaging body.

For example, food products may be packaged by a film such as a polypropylene film or a polyethylene film after production or shipment and before distribution to the market. In this case, the food may be oxidized and discolored by oxygen in the bag.

  As a method for maintaining food freshness, there is a method of treating food with an aqueous solution containing alum and a pH adjuster and having a pH of 2.75 to 3.75, as described in Patent Document 1. However, in the method described in Patent Document 1, the use of chemicals has been a problem.

JP-A-9-084517

  An object of the present invention is to provide a food packaging sheet capable of preventing discoloration of food and a food packaging bag.

  Such an object is achieved by the present inventions (1) to (10) below.

(1) A food packaging sheet used for packaging food, comprising a first layer and a second layer, wherein the thickness of the second layer is 3 μm or more and 30 μm or less, The food packaging sheet, wherein the food packaging sheet has an oxygen permeability of 20 cc / m ² · day · atm or more and 250 cc / m ² · day · atm (23 ° C., 90% RH) or less.

 (2) The food packaging sheet according to (1), wherein the first layer contains a polyester resin or a polyamide resin.

 (3) The food packaging sheet according to (1) or (2), wherein the thickness of the first layer is 5 μm or more and 30 μm or less.

 (4) The food packaging sheet according to any one of (1) to (3), wherein the second layer includes a polyolefin resin.

 (5) The food packaging sheet according to any one of (1) to (4), wherein a thickness of the food packaging sheet is 20 μm or more and 40 μm or less.

 (6) A food packaging bag, wherein the food packaging sheet according to any one of (1) to (5) is formed into a bag shape.

  (7) The food packaging bag according to (6), wherein the width and length are 250 mm or less.

(8) surface area of the bag per food 100g to be packaged, characterized in that at 0.05 m ² or more 0.13 m ² or less, food packaging bag according to (6) or (7).

 (9) The food packaging bag according to any one of (6) to (8), which is used for packaging lettuce.

  (10) The food packaging bag according to any one of (6) to (9), which is used for packaging cut lettuce.

  (11) The thickness of the food packaging bag according to any one of (6) to (10) is 0.5 cm or more and 3 cm or less after the food is sealed, degassed and packaged. Food packaging body.

  According to the present invention, a food packaging sheet capable of preventing discoloration of food can be obtained. Moreover, the food packaging bag comprised with this food packaging sheet can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure ((a) is a top view, (b) is the sectional view on the AA line in Fig.1 (a)) which shows typically the food packaging body of this invention. It is sectional drawing of the sheet | seat for food packaging shown in FIG.

Hereinafter, the food packaging sheet and food packaging bag of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.
<Food packaging>
FIG. 1 is a diagram schematically showing a first embodiment of a food packaging body according to the present invention ((a) is a plan view, (b) is a cross-sectional view taken along line AA in FIG. 1 (a)), FIG. These are sectional drawings of the sheet | seat for food packaging shown in FIG.

  In the following description, the upper side in FIG. 1 is referred to as “upper”, the lower side is referred to as “lower”, the left side is referred to as “left”, and the right side is referred to as “right”. In addition, the drawings referred to in this specification show part of the configuration in an exaggerated manner, and do not accurately reflect actual dimensions and the like.

  A food packaging body 100 shown in FIG. 1 has a food packaging bag 50 and a food 1 packaged in a state of being sealed with the food packaging bag 50.

  The food 1 is not particularly limited. For example, fruits such as banana, mango, ume, apple, strawberry, mandarin orange, grape, Japanese pear, and pear, radish, carrot, yam, root vegetables such as burdock, Fruit vegetables such as tomato, cucumber, eggplant, bell pepper, green beans, okra, mung bean sprout, soybean sprout, sprout such as cypress, fungi (mushrooms) such as shiitake, shimeji, eringi, maitake, matsutake , Broccoli, Spinach, Komatsuna, Chingensai, Lettuce, Leaf and stem vegetables such as asparagus, chrysanthemum, lily, carnations and other fruits and vegetables, and processed and cooked products thereof (for example, pickles, jams, Fruit sauce, etc.), chicken, pork, beef, fish and other meats and their processed and cooked products (eg, salmon, chikuwa, sausage, Etc.), buns, chocolate, gum, jelly, agar, cookies and other confectionery, milk, yogurt, cheese and other dairy products, soy sauce, miso and other seasonings, liquor, soft drinks and other liquid beverages or jelly-like Examples include beverages, supplements (dietary supplements), health foods such as functional health foods, noodles such as udon and soba, breads, rice, potatoes, etc., or combinations thereof. Can also be packaged in the food packaging bag 50. In addition, as a drink, what is called powder drinks, such as tea leaves, such as teas, such as green tea and hojicha, and tea, various tea packs, cocoa, powdered juice, etc. may be sufficient.

  Such a food 1 is stored in a food packaging bag 50 to form a food packaging body 100, and is displayed and sold in, for example, a market or a retail store.

Hereinafter, the packaging bag for food with which the food packaging body of this invention is provided is demonstrated.
<Food packaging bag>
A food packaging bag 50 shown in FIG. 1 is a food packaging container used for storing food.

 The food packaging bag 50 is composed of the first sheet 10a and the second sheet 10b having a rectangular shape as the food packaging sheet 10, and the three sides are bonded and melted after overlapping each other. It is formed into a bag shape by joining by sewing or the like. In FIG. 1, the joined portion is shown as a seal portion 52 with shading.

 Further, as shown in FIG. 1, the food packaging bag 50 has a space 53 formed therein, and a sealing portion 54 provided on the right side of the food packaging bag 50 in FIG. ing. This sealing part 54 is obtained by sealing the mouth part opened to the right side in Fig.1 (a) of the food packaging bag 50. FIG. In addition, as a method of sealing the sealing part 54, for example, the mouth part is made of metal or resin, and the mouth part is tied with a rubber band, a tape, a zipper, or the like, or the mouth part is bonded, melted (heat sealed), and sewn. Any method may be used.

 The food packaging body 100 as shown in FIG. 1 puts the food 1 into the space 53 of the food packaging bag 50 having such a configuration through the mouth portion, and then seals the mouth portion by the method as described above. Can be obtained. At this time, since the three sides of the food packaging bag 50 are joined by the seal portion 52, the food 1 is prevented from falling off the food packaging bag 50.

  The thickness of the food packaging body 100 is preferably 3 cm or less when the food 1 is put into the space 53 of the food packaging bag 50 through the mouth and then deaerated and packaged. Thereby, the discoloration prevention effect of food is acquired. In addition, the thickness of the food package 100 is preferably 0.5 cm or more when the food 1 is put in the space 53 of the food packaging bag 50 through the mouth and then deaerated and packaged. This is preferable because the food of the contents is not crushed. 1 cm or more is more preferable.

  The width and length of the food packaging bag 50 are preferably 250 mm or less. Thereby, the workability | operativity at the time of deaeration and packaging the food packaging bag 50 improves.

The surface area of the food packaging bag 50, per 100g of the food 1 is preferably 0.05 m ² or more 0.13 m ² or less. Thereby, it becomes easy to put food into the food packaging bag 50 while having the effect of preventing discoloration of the food.

Below, the sheet | seat 10 for food packaging which forms the food packaging bag 50 of such a structure is demonstrated.
<Food packaging sheet>
As shown in FIG. 2, the food packaging sheet 10 includes a first layer 11 and a second layer 12.

 Hereinafter, the first layer 11 and the second layer 12 will be sequentially described.

(First layer 11)
The first layer 11 has an appropriate oxygen permeability and has a function of preventing oxygen outside the bag from permeating into the bag.

  The first layer 11 is preferably a transparent resin film layer from the viewpoint of confirming the contents.

 The first layer 11 contains a resin. The resin is not particularly limited, and examples thereof include polyester resins, polyamide resins, and polyolefin resins.

  The first layer 11 preferably contains a polyester resin or a polyamide resin. Thereby, the sheet | seat 10 for food packaging has a moderate oxygen permeation effect. As the polyester-based resin, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polylactic acid or the like is preferably used alone or in combination of two or more, and polyethylene terephthalate alone is more preferable. Nylon is preferable as the polyamide resin. Nylon 6, Nylon 11, Nylon 12, Nylon 66, Nylon 6 · 10, Nylon 6 · 12, Nylon 6 · T, Nylon 6 · I, Nylon 9T, Nylon M5T, Polymetaxylylene adipamide (MXD Nylon) ), Etc., or a combination of two or more, such as nylon 6, nylon 11, nylon 12, and nylon 66 is more preferable, or a combination of two or more is more preferable, and a combination of nylon 6 and nylon 66 is also a combination of two or more. preferable.

  The first layer 11 can contain an inorganic filler as necessary. The inorganic filler is not particularly limited. For example, a mineral (inorganic crystal) such as zeolite, sepiolite, diatomaceous earth, silica, silica gel, arobene, imogolite, montmorillonite, attapulgite, or zonotlite may be used.

  If necessary, the first layer 11 may be a heat stabilizer, a lubricant, an antifogging agent, an impact resistance improving agent, a processing aid, an antistatic agent, an ultraviolet absorber, an antioxidant, an anti-wrinkle-proofing agent, or a filling. Additives such as agents, pigments, and the like can be contained within a range that does not impair the performance of the resin film.

  Moreover, as the 1st layer 11, the thing of the multilayer film which laminated | stacked two or more layers of the single layer film containing the resin material as mentioned above, or the single layer film comprised with the resin material can be used. In addition, in the case of a multilayer film, it may be comprised with the same material and may be comprised with a different material. Moreover, the 1st layer 11 may laminate | stack metal foil, paper, a nonwoven fabric, etc. on the film (a single layer film and a multilayer film) containing a resin material.

  The thickness of the first layer 11 is preferably 5 μm or more, more preferably 10 μm or more, on the other hand, preferably 30 μm or less, more preferably 20 μm or less. By making the thickness of the 1st layer 11 into 5 micrometers or more and 30 micrometers or less, the appearance of the food packaging bag 50 is made favorable, and moderate oxygen permeability and intensity | strength are obtained. Moreover, moderate flexibility can be obtained.

(Second layer 12)
The second layer 12 has a function of supporting the first layer 11 and making the strength and the like of the food packaging sheet 10 as a whole suitable.

  The second layer 12 contains a resin. The resin is not particularly limited, and examples thereof include polyethylene, polypropylene, ethylene-vinyl alcohol copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methyl methacrylate copolymer, and ionomer. . The resin contained in the second layer 12 is a polyolefin resin in order to make it easy to seal while obtaining sufficient sealing strength stably when packaging fruits and vegetables from the food packaging sheet 10 with an automatic packaging machine. Preferably, these polyolefin resins can be used alone or in combination of two or more. Of the polyolefin-based resins, polyethylene, polypropylene, or ethylene vinyl acetate copolymer is more preferable.

  The second layer 12 is made of zeolite, sepiolite, diatomaceous earth, silica, silica gel, arobene, imogolite, montmorillonite, attapulgite, or zonotlite to prevent blocking of the film or adjust its water vapor permeability and water contact angle. May contain various minerals.

  If necessary, the second layer 12 is made of an antifogging agent, a heat stabilizer, a lubricant, an antifogging agent other than the above, an impact resistance improving agent, a processing aid, an antistatic agent, an ultraviolet absorber, or an antioxidant. Further, additives such as anti-wrinkle resistance inhibitor, inorganic particles, fillers and pigments may be contained.

  The thickness of the second layer 12 is 3 μm or more, preferably 8 μm or more, more preferably 14 μm or more, and on the other hand, 30 μm or less, preferably 25 μm or less, and more preferably 20 μm or less. By setting the thickness of the innermost layer 3 to 3 μm or more, it is possible to maintain the strength of the food packaging bag 50 manufactured by the food packaging sheet 10 and to obtain high sealing performance of the bag. Body flexibility and transparency can be obtained.

(Other layers)
The third layer 13 can be provided between the first layer 11 and the second layer 12 as necessary. Thereby, the adhesiveness of the 1st layer 11 and the 2nd layer 12 can be improved more.

  The third layer 13 is a so-called adhesive resin such as modified polyethylene, modified polypropylene, modified ethylene / vinyl acetate copolymer, modified polyester, or so-called anchor such as urethane, titanate, imine, butadiene, or olefin. A resin containing an adhesive such as a coating agent, polyester or polyether may be included.

The oxygen permeability of the food packaging sheet 10 is preferably 20 cc / m ² · day · atm or more and 250 cc / m ² · day · atm (23 ° C., 90% RH) or less. More preferably, it is 20 cc / m ² · day · atm or more, 200 cc / m ² · day · atm (23 ° C., 90% RH) or less, more preferably 20 cc / m ² · day · atm or more, 150 cc / m ^2. -Day-atm (23 ° C., 90% RH) or less. Thereby, the preservability of foodstuffs can be improved.

The water vapor permeability of the food packaging sheet 10 is preferably 20 g / m ² · day or less, and more preferably 10 g / m ² · day to 100 g / m ² · day. By setting the amount to 20 g / m ² · day or less, moisture from the outside enters the inside of the food packaging bag 50 while reducing the influence of the environment outside the food packaging bag 50 and suppressing the evaporation of moisture from the food itself. Can be suppressed. Thereby, drying of the foodstuff in the food packaging bag 50 can be prevented. The water vapor permeability is measured according to JIS Z 0208 (40 ° C., 90% RH).

 The thickness of the food packaging sheet 10 is preferably 20 μm or more, more preferably 25 μm or more, on the other hand, preferably 40 μm or less, more preferably 35 μm or less. By setting the thickness of the food packaging sheet 10 to 20 μm or more, good strength can be obtained in the food packaging bag 50, and by setting the thickness to 50 μm or less, appropriate flexibility can be obtained.

  The transparency of the food packaging sheet 10 is preferably 2% or more and 10% or less, and more preferably 3% or more and 8% or less. By setting the haze in the range of 2% or more and 10% or less, transparency can be obtained when the food packaging bag 50 is made, the contents (such as fruits and vegetables) of the packaging bag can be distinguished sufficiently, and a good appearance can be obtained. It is done.

  The haze is a value obtained by dividing the diffuse light transmittance by the total light transmittance, and is measured according to JIS K7105.

  The food packaging sheet 10 is formed by laminating the first layer 11 and the second layer 12 having the above-described characteristics such as material and thickness by an extrusion lamination method, a dry lamination method, a co-extrusion lamination method, a coating method, and the like. Obtained by. Any lamination method may be used.

  Note that the first sheet 10a and the second sheet 10b may have the same configuration or different configurations. For example, the film thicknesses and constituent materials of the first sheet 10a and the second sheet 10b may be different from each other.

  The food packaging bag 50 can store fruits and vegetables to prevent condensation. That is, the food packaging bag 50 can suppress fogging of the inner surface of the food packaging bag 50 caused by water vapor due to respiration of the fruits and vegetables contained therein, and can suppress the occurrence of condensation even if stored for a long time. The reason for this is considered that moisture adhering to the inner surface of the food packaging bag 50 spreads in a film shape by the second layer 12 of the multilayer film 10 for fruit and vegetable packaging bags, and therefore it is considered that dew condensation can be suppressed.

  The food 1 that is the contents of the food packaging bag 50 of the present embodiment is preferably one that changes color by oxidation, and includes lettuce, cabbage, Chinese cabbage, cut lettuce, and cut apple, but lettuce is suitable. Cut lettuce is particularly suitable.

In the present invention, the oxygen permeability of the food packaging sheet 10 is 20 cc / m ² · day · atm or more and 250 cc / m ² · day · atm (23 ° C., 90% RH) or less, and the second layer. When the thickness of 12 is 3 μm or more and 30 μm or less, the food packaging sheet 10 obtains appropriate high sealing performance, flexibility, and transparency, so when food is put into the food packaging bag 50 and deaerated, The food packaging bag 50 is not damaged when pressure is applied, and furthermore, since it has an appropriate oxygen permeability, the freshness of the food that is the content is sufficient even if the food packaging bag 50 is not replaced with nitrogen. It is to be retained.

 As mentioned above, although embodiment of the sheet | seat for food packaging of this invention, a food packaging container, and a food packaging body was demonstrated, this invention is not limited to these.

 For example, each part which comprises the sheet | seat for food packaging of this invention, a food packaging container, and a food packaging body can be substituted with the thing of the arbitrary structures which can exhibit the same function. Moreover, arbitrary components may be added.

 Moreover, in the said embodiment, although the food packaging bag demonstrated as what formed two sheets for food packaging on the bag shape, it is not limited to this, For example, one sheet for food packaging May be formed into a bag shape by folding the two into two and joining two opposing sides. When a food packaging bag is formed by folding a single food packaging sheet into two, one side is the first sheet and the other side is the second, with the folded portion as a boundary. It will be used as a sheet. Further, a bag made by an automatic packaging machine such as a vertical pillow machine may be used.

 In addition, the food packaging bag may be, for example, a bag in the form of a gusset bag or a trapezoidal bag, and further, a form in which food is filled in trays, cups, etc., and this is packed in a food packaging bag. It may be.

 Moreover, in the said embodiment, although the food packaging bag was entirely comprised with the sheet | seat for food packaging, the whole food packaging bag does not need to be comprised with the sheet | seat for food packaging. For example, the food packaging bag may be a combination of a food packaging sheet having a second layer and a sheet composed of only the first layer not having the second layer.

 In the above embodiment, the example in which the second layer 12 is stacked on one side of the first layer 11 has been described. However, the second layer 12 may be stacked on both sides of the first layer 11. .

 Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited by the following examples. In addition,% and part described in the following examples and comparative examples represent mass% and mass part.

<Creation of food packaging bag sheet>
Using the raw materials shown in the following examples and comparative examples, multilayer films were produced by extrusion lamination.

 The obtained food packaging sheets were all transparent (haze 10% or less: JIS K7105 compliant).

Example 1
As a raw material of the first layer, a polyethylene terephthalate film (Futamura Chemical Co., Ltd., FE2001) having a thickness of 16 μm was used.

 As a raw material for the second layer, a low-density polyethylene (Ube Maruzen Polyethylene Co., Ltd., UBE Polyethylene L719) blended with an antifogging agent masterbatch (RIKEN Vitamin Co., Ltd., Riquete Master EAR-5) in a ratio of 7: 1. Was used.

 A food packaging sheet having a total thickness of 31 μm and a second layer thickness of 15 μm was produced using the above raw materials.

<Production of food packaging bags>
A part of the food packaging sheet obtained above was cut out to prepare two rectangular sheets (first sheet and second sheet) having the same dimensions. Thereafter, the first sheet and the second sheet were overlapped with each other so that the respective second layers were inside, and the three sides were fused by heat sealing. As a result, a food packaging bag having an inner size of 170 × 180 mm was produced.

 The thickness of the food packaging sheet, the thickness of the second layer, the oxygen permeation amount, and the food preservability of the food packaging bag obtained from the food packaging sheet were measured.

(Example 2)
A food packaging sheet and a food packaging bag were prepared in the same manner as in Example 1 except that a low-density polyethylene layer having a thickness of 5 μm was provided as the second layer, and physical properties were measured.

(Example 3)
A food packaging sheet and a food packaging bag were prepared in the same manner as in Example 1 except that a low-density polyethylene layer having a thickness of 20 μm was provided as a raw material for the second layer, and physical properties were measured.

Example 4
A food packaging sheet and a food packaging bag were prepared in the same manner as in Example 1 except that a polyethylene terephthalate film having a thickness of 12 μm was used as a raw material for the first layer, and physical properties were measured.

(Example 5)
A food packaging sheet and a food packaging bag were prepared in the same manner as in Example 4 except that a low-density polyethylene layer having a thickness of 30 μm was provided as a raw material for the second layer, and physical properties were measured.

(Example 6)
As a raw material for the second layer, an antifogging agent master batch (RIKEN VITAMIN Co., Ltd., Riquete Master PAR-380) was blended at a ratio of 5: 1 with respect to polypropylene (Sumitomo Chemical Co., Ltd., Sumitomo Nobrene FS2011DG2). A food packaging sheet and a food packaging bag were prepared in the same manner as in Example 1 except that the polypropylene layer was provided, and the physical properties were measured.

(Example 7)
A food packaging sheet and a food packaging bag were prepared in the same manner as in Example 1 except that a biaxially stretched nylon film (Unitika Ltd., Emblem ONBC) having a thickness of 15 μm was used as the raw material for the first layer. Was measured.

(Comparative Example 1)
As a raw material for the first layer, a food packaging sheet and a food packaging bag were prepared in the same manner as in Example 1 except that a biaxially stretched polypropylene film (Toyobo Co., Ltd., Pyrene Film-OTP2102) having a thickness of 20 μm was used. Physical property values were measured.

(Comparative Example 2)
A food packaging sheet and a food packaging bag were prepared in the same manner as in Example 1 except that a polypropylene layer having a thickness of 50 μm was provided as a raw material for the second layer, and physical properties were measured.

<Measurement method>
(Thickness of food packaging sheet)
The thickness of the sheet for food packaging was measured with a continuous thickness measuring device film tester S-2270 (manufactured by Fuji Work Corporation). The width of the test piece was 50 mm, and the film feed rate during measurement was 1.5 m / min.

(The thickness of the second layer of the food packaging sheet)
The thickness of the 2nd layer of the sheet | seat for food packaging observed the cross section of the sheet | seat for food packaging, and measured the thickness of the 2nd layer. Or the cross section of the sheet | seat for food packaging was observed, and the thickness of the 2nd layer was computed from the ratio of the 2nd layer with respect to the whole sheet | seat for food packaging.

(Oxygen transmission rate)
The oxygen permeation amount (oxygen permeability) of the resin film was measured by the Mokon method (23 ° C., 90% RH) standardized in JIS 7126B.

(Cut lettuce storage test)
Inject the cut lettuce 95g into the above-obtained food packaging bag with an internal size of 170 x 180mm, degass it by applying pressure from the top, and then open the mouth of the food packaging bag (mouth) Was sealed with a heat seal to obtain a package (food package).

  This package was stored at 10 ° C. for 4 days, and the presence or absence of discoloration of cut lettuce was confirmed.

(Measurement of food packaging thickness)
Place the food packaging body obtained above on two flat plates placed so that the planes are parallel, and compress the bag so that the bag does not rupture (300-500 gf). It was measured.

  The results are shown in Table 1.

From the evaluation results in Table 1, the food packaging bags of each example were excellent in food preservability. On the other hand, in Comparative Example 1 using a laminated film whose oxygen permeability is not more than 20 cc / m ² · day · atm and not more than 250 cc / m ² · day · atm (23 ° C., 90% RH), food preservation Sex was not enough. Further, in Comparative Example 2 in which the thickness of the second layer is not 3 μm or more and 30 μm or less, the food packaging bag cannot be sufficiently crushed, so that the deaeration becomes insufficient and the food preservability is not sufficient. It was.

1: Food 10: Food packaging sheet 10a: First sheet 10b: Second sheet 11: First layer 12: Second layer 50: Food packaging bag 52: Seal part 53: Space 54: Sealing part 100: Food packaging body

Claims (11)

A food packaging sheet used for packaging food, wherein the food packaging has a first layer and a second layer, and the thickness of the second layer is 3 μm or more and 30 μm or less. A sheet for food packaging, wherein the oxygen permeability of the sheet is 20 cc / m ² · day · atm or more and 250 cc / m ² · day · atm (23 ° C., 90% RH) or less.  The food packaging sheet according to claim 1, wherein the first layer includes a polyester resin or a polyamide resin.   The thickness of the said 1st layer is 5 micrometers or more and 30 micrometers or less, The sheet | seat for food packaging of Claim 1 or 2 characterized by the above-mentioned.   The food packaging sheet according to any one of claims 1 to 3, wherein the second layer contains a polyolefin-based resin.  The sheet for food packaging according to any one of claims 1 to 4, wherein the thickness of the sheet for food packaging is 20 µm or more and 40 µm or less.   A food packaging bag, wherein the food packaging sheet according to any one of claims 1 to 5 is formed into a bag shape.   The food packaging bag according to claim 6, wherein the width and length are 250 mm or less. The surface area of the bag per food 100g to be packaged, characterized in that at 0.05 m ² or more 0.13 m ² or less, food packaging bag according to claim 6 or 7.   The food packaging bag according to any one of claims 6 to 8, wherein the food packaging bag is used for packaging lettuce.   The food packaging bag according to any one of claims 6 to 9, which is used for packaging cut lettuce.  A food packaging body having a thickness of 0.5 cm or more and 3 cm or less after the food is sealed, degassed and packaged in the food packaging bag according to any one of claims 6 to 10. .