JPH0515381B2 - - Google Patents

Description

[Detailed description of the invention]

purpose of invention

TECHNICAL FIELD The present invention relates to a food container that prevents the flavor components of food from being absorbed into the food container and causing the flavor to deteriorate.

[Conventional technology]

In recent years, containers for liquids and viscous foods have not only been used traditionally, such as glass bottles and metal cans, but also containers made of laminated plastic film and composite containers called pillared cups made of paper and plastic. has come to be used. Along with this, deterioration in the flavor of foods has become a problem. In particular, in the case of citrus fruit juices or foods containing a large amount thereof, terpene hydrocarbons such as d-limonene, which constitute the flavor components thereof, are easily absorbed by polyolefin resins widely used in packaging materials. The same situation applies to other citrus terpenes such as α-pinene and myrcene, isoamyl acetate, which is an apple flavor component, and hexyl acetate, which is a banana flavor component. If the flavor components of food are significantly reduced or imbalanced during storage, it is inevitable that the flavor of the food will deteriorate. If a resin with a high solubility parameter such as polyester or polyamide is used instead of polyolefin resin, absorption of flavor components will be small;
Due to its low heat-sealing strength, it is not suitable as a packaging material for liquid foods, and it is also expensive.

[Problems to be solved by the invention]

An object of the present invention is to break through the deadlock in the art described above and to provide a food container that minimizes the absorption of flavor components of liquid or viscous foods into the food container and deterioration of flavor. It is in. Composition of the invention

[Means to solve the problem]

The food container of the present invention is a food container made of a laminated material whose innermost surface is a layer of polyolefin resin.
It is characterized in that the amount of polyolefin resin is 0.5% or less. As the polyolefin resin, polyethylene, particularly low-density polyethylene, is preferable because it can be easily heat-sealed. In addition to this, polypropylene,
Ethylene-2-olefin copolymer, ethylene-
Vinyl acetate copolymers, ionomers and other ethylene copolymers can be used. In a preferred embodiment, a material is used in which a layer of plastic having a low absorption rate of food flavor components is laminated on the outside of a layer of polyolefin resin. Plastics having a low absorption rate of food flavor components may be selected from polyamide, polyester, saponified ethylene-vinyl acetate copolymer, polyvinyl alcohol, polyacrylonitrile, and polystyrene. The plastic layer and the polyolefin resin layer may be laminated by a co-extrusion method. According to this method, it is possible to easily form a layer of polyolefin resin with a thickness of 30 μm or less, and the heat sealing strength is also increased. In this case, if necessary, a layer of a conventional adhesive can be provided between the plastic layer and the polyolefin resin layer, for example by a three-layer co-extrusion process, to increase the adhesive strength between the two layers. The food containers of the present invention include pouches made of aluminum laminate material with four-sided seals, back-in boxes,
There are pillared cups, tetrabricks, Gebert cups, and standing pouches.

[Effect]

As a result of various studies, the inventors confirmed that the amount of food flavor components lost during storage depends on the amount of polyolefin resin, which is widely used on the inner surface of food containers. quantity 100
% (weight), the amount of polyolefin resin
I learned that if the amount is kept to a small amount of 0.5% or less, the amount of food flavor components absorbed into the container is small, and the flavor can essentially be preserved. For example, fruit juice 100
A pouch containing 200 ml of % Orange Youth satisfies the above conditions if the thickness of the polyolefin resin layer is approximately 10 to 30 μm. In an embodiment in which a plastic layer with a low absorption rate for food flavor components is laminated on the outside of the polyolefin resin layer, even if flavor components are absorbed into the polyolefin resin layer, they are blocked by the outer plastic layer and do not escape to the outside. Therefore, no further absorption occurs. A thin layer of polyolefin resin will generally have low heat seal strength, but an outer plastic layer will have high heat seal strength. Example 1 1 (Example) Ethylene-vinyl acetate copolymer
A laminated film of 40μ/vinylidene chloride coated polyamide 15μ/50μ of ethylene-vinyl acetate copolymer and a film of 80μ of ethylene-vinyl acetate copolymer are stacked together, heat-sealed on all sides, and placed in a bag-in box with a spout attached. 570× called a bag
A bag of 570 mm was formed. This bag is sterilized with gamma rays, and the aseptic filling machine "DN-
AB” (Dainippon Printing), this bag contains fruit juice.
20 aseptically filled bottles of 100% concentrated reduced orange juice. 2 (Example) Polyester 12μ/aluminum
9μ/stretched nylon 15μ/low density polyethylene 60μ
The laminated film was sterilized with hydrogen peroxide to form a 250 x 360 mm bag sealed on three sides. Using an aseptic filling machine "DN-ABR" (Dainippon Printing Co., Ltd.), this bag was aseptically filled with 100% concentrated reduced orange juice. 3 (Comparative example) Same material as 1 above, 370 x 370 mm
A bag was formed. This bag was aseptically filled with 100% concentrated orange juice in the same manner as in Example 1. 4 (Comparative Example) One can of 100% concentrated orange juice was filled in a sterile room. After storing the above-mentioned packings 1 to 4 at a temperature of 20° C. for 10 days, they were analyzed by headspace gas chromatography to measure the amount of d-limonene. The results are shown together with the ratio of the amount of polyethylene in the container to the fruit juice. No. Polyethylene amount D-Limonene amount 1 0.39 (%) 0.61 (g/) 2 0.33 0.68 3 0.35 0.35 4 0 0.75 The sensory test results for these samples are as follows. No. Fresh flavor taste 1 Yes Good 2 Yes Good 3 No Bad 4 Yes Good example 2 5 (Example) Polyester 12μ/aluminum
A laminated film of 9μ/unstretched nylon 30μ/adhesive layer 10μ/low density polyethylene 10μ was prepared. The method involves first bonding polyester and aluminum together using a dry lamination method, then forming a three-layer film of unstretched nylon/adhesive layer/low-density polyethylene using a three-layer co-extrusion method, and then attaching the aluminum surface to the aluminum surface. and an unstretched nylon surface are bonded together by a dry lamination method. 6 (Example) Polyester 12μ/aluminum
A laminated film of 9μ/unstretched nylon 10μ/adhesive layer 10μ/low density polyethylene 20μ was prepared in the same manner as No. 5. 7 (Example) Polyester 12μ/aluminum
A laminated film of 9μ/unstretched nylon 30μ/adhesive layer 10μ/low density polyethylene 20μ was prepared in the same manner as No. 5. 8 (Comparative example) Polyester 12μ/aluminum
A laminated film of 9μ/15μ low density polyethylene was prepared. The method involves first bonding polyester and aluminum together using a dry lamination method, and then applying low-density polyethylene to the aluminum surface using an extrusion coating method. 9 (Comparative example) Polyester 12μ/aluminum
9μ/low density polyethylene 30μ laminated film,
Prepared in the same manner as No. 8. 10 (Comparative example) Polyester 12μ/aluminum
9μ/low density polyethylene 60μ laminated film,
Prepared in the same manner as No. 8. 11 (Comparative example) Polyester 12μ/aluminum
9μ/100μ low density polyethylene laminated film,
Prepared in the same manner as No. 8. The heat seal strengths of the laminated films of Nos. 5 to 7 (Examples) and Nos. 8 to 11 (Comparative Examples) were measured using a Tensilon tensile tester, and the results are shown in the table below. No. Heat seal strength 5 4.9 (Kg/15mm width) 6 4.3 7 5.7 8 0.75 9 0.90 10 2.4 11 3.1 Next, each of these laminated films was sealed on three sides to form a bag with an inner dimension of 11 x 16 cm. Each bag was filled with 200 ml of 100% orange juice. After storing this packed product at a temperature of 3° C. for 7 days, the air in the head space was analyzed by gas chromatography to measure the amount of d-limonene therein. The glass bottle was filled with 200 ml of 100% orange juice and the amount of d-limonene measured under the same conditions was used as the initial value. The results are shown in the diagram in relation to the thickness of the low density polyethylene layer. The thickness of No. 5 was the total thickness of the adhesive layer and the low density polyethylene of 20 μm, and the thickness of No. 6 and No. 7 was also plotted with a total thickness of 30 μm. Effects of the Invention By using the food container of the present invention, absorption of flavor components of liquid or viscous food into the food container is minimized, and deterioration of the flavor of the food can be substantially prevented. Therefore, this food container is most suitable as a container for citrus fruit juice drinks and viscous foods such as jam.

[Brief explanation of the drawing]

The drawing is a graph showing the effects of the food container of the present invention.

Claims (1)

[Claims] 1. Amount of food to be filled in a food container made of a laminated material whose innermost surface is a layer of polyolefin resin
A food container characterized in that the amount of polyolefin resin is 0.5% or less relative to 100% (weight). 2 As polyolefin resin, polyethylene,
2. A food container according to claim 1, which is made of polypropylene, ethylene-2-olefin copolymer, ethylene-vinyl acetate copolymer, ionomer and other ethylene copolymers. 3. The food container according to claim 1, wherein a plastic layer having a low absorption rate of food flavor components is laminated on the outside of the polyolefin resin layer. 4. As the plastic with a low absorption rate of food flavor components, a plastic selected from polyamide, polyester, saponified ethylene-vinyl acetate copolymer, polyvinyl alcohol, polyacrylonitrile, and polystyrene is used. food container. 5. The food container according to claim 3, wherein an adhesive layer is provided between the polyolefin resin layer and the plastic layer.