WO2015036264A1

WO2015036264A1 - Container for aseptic content

Info

Publication number: WO2015036264A1
Application number: PCT/EP2014/068433
Authority: WO
Inventors: Niels Stoffers; Lutz ELLMANN; Sébastien Rime
Original assignee: Nestec S.A.
Priority date: 2013-09-12
Filing date: 2014-08-29
Publication date: 2015-03-19

Abstract

A container (1), the content of which is an aseptic fluid, said container being equipped with a closure system comprising a removable flexible lid (2) sealed to the container neck (5) and a removable cap (3) adapted to the container over the flexible lid and provided with at least one device (4), which forms an integral part of the cap (3), compresses the neck (5) of the container without damaging the flexible lid (2) and prevents the top of the cap (8) from entering into contact with the flexible lid (2), so that a headspace (6) extends between at least part of the upper surface of the flexible lid (2) and the inner surface (7) of the top (8) of the cap (3) wherein the headspace is provided with at least one orifice, which is permeable to gas with a flow of at least 300 ml/mm at 50 to 300 mbar differential pressure and impermeable to liquids with water-like properties when the container (1) is shaken or tilted.

Description

Container for aseptic content

Field of the invention The present invention relates to a container equipped with a closure system particularly adapted for aseptically filled fluid contents. The invention also relates to the use of said container in a method for detecting spoilage of its fluid content.

Background of the invention

There is a need for containers allowing detection of spoilage of the packaged fluids during storage. It would further be desirable to detect spoilage using non-destructive methods and without opening the package. Such methods would be even more advantageous for products which are aseptically filled such as nutritional or health care compositions or compositions intended for particularly sensitive consumers, such as for example infants.

DE 100 22 177 B4 discloses a means for signalling the state of a liquid contained in a bottle consisting of a cap having a transparent top and equipped with a flexible membrane that is deflected when the container is closed due to the internal pressure present in the bottle and subsequently in a flat position after the bottle has been opened. The visual aspect of the top surface of the membrane when it is deflected is different from the visual aspect of said upper surface when the membrane is in flat position, thus allowing visual identification of the state of the content. The system described in this document is mainly useful for bottles containing carbonated beverages which create a higher pressure inside than outside the container when the bottle is closed and the content is carbonated (deformed membrane), whereas the membrane is flat when the liquid is de-carbonated or the container has been opened (no pressure difference between inside and outside the container). However, this cap is not suited for aseptically filled content and is therefore not suitable to solve the above problem. Summary of the invention

In a first aspect, the invention relates to a container (1 ), the content of which is an aseptic fluid, said container being equipped with a closure system comprising

a) a removable flexible lid (2) sealed to the container neck (5), and

b) a removable cap (3) adapted to the container over the flexible lid and provided with at least one device (4), which forms an integral part of the cap (3), compresses the neck (5) of the container without damaging the flexible lid (2) and prevents the top of the cap (8) from entering into contact with the flexible lid (2), so that a headspace (6) extends between at least part of the upper surface of the flexible lid (2) and the inner surface (7) of the top (8) of the cap (3)

characterized in that

i) the headspace is provided with at least one orifice,

ii) the orifice is permeable to gas with a flow of at least 300 ml/min (milliliter per minute) at 50 to 300 mbar differential pressure; and

iii) The orifice is impermeable to liquids with water-like properties when the container (1 ) is shaken or tilted.

In another aspect, the invention relates to the use of a container of the invention in a method for detecting spoilage of its content.

In a further aspect the invention relates to a method for detecting spoilage of the content of the container of the invention comprising the step of detecting the deflection of the flexible lid.

In a further aspect the invention relates to a method for the production of a container according to the invention, characterized in that it comprises the step of aseptically filling a container with an aseptic fluid product and closing the container with a closure system as described in any of the embodiments of the invention. Brief Description of the Drawings

Figure 1 is a graphical representation of the container of Example 1 . The upper part of the container is shown with the closure system of the invention. Figure 1A shows a side view of the upper part of the closed container. Figure 1 B shows a section view of the closed container when the content is aseptic. The flexible lid (2) adheres to the top of the container neck (5). There is no over-pressure in the container, so that the lid (2) is not deflected. A screw cap (3) is adapted to the container neck (5). The device (4) forming an integral part of the screw cap (3) compresses the container neck (5) so that a headspace (6) extends between the lid (2) and the inner surface (7) of the top (8) of the cap (3).

Figure 2 is a graphical representation of the cap of the container of Example 1 , seen from below. The circular device (4) intended to be compressed on the neck of the container is provided with an uneven structure having twenty cavities (9). When the cap is closed and the device is compressed on the container neck, a headspace is formed having twenty orifices, each orifice being delimited by the shape of the cavities (9) and by the surface of the container neck (5). Figure 3 is an enlarged view of the upper left quarter of the cap of figure 2. This representation shows that each cavity is provided through the whole thickness of the device, so that a venting orifice is formed when the device is compressed on the container neck, this orifice allowing gas to exit the headspace. Figure 4 represents an isometric view of the cap of the container of Example 1. The circular device (4) is provided with cavities (9).

Figure 5 represents a detailed view of one orifice provided in the headspace of the container of Example 1 . The shape of the cavity (9) provided in the device (4) is represented in solid lines, whereas the surface of the container neck (5) is represented in dashed lines. Figure 5A represents a detailed view of an orifice seen from the inside of the headspace. The inner opening (10) (largest opening) is linked to the outer opening (1 1 ) (smallest opening) by a channel (12). Figure 5B represents the shape and size of the outer opening (1 1 ) (smallest opening). Figure 6 represents a section view of the container of Example 1 . The flexible lid is represented in two different alternative positions. When the flexible lid is in position (2), the content of the container is sterile. When the flexible lid is in position (2'), the content of the container is spoiled.

Detailed description of the invention

The present inventors have now developed an aseptically filled container having a specific closure system that allows for non-destructive detection of spoiled fluid content.

The container body can be of any type that is suitable for aseptic filling of liquids. The container body can be made of any material suitable for such use, such as glass or plastic. Most preferably it is made of plastic. It can also have diverse shapes. Preferably, it is in the form of a bottle. A typical feature of container bodies suitable for aseptic filling of liquid is that they are made of a material that is impermeable to liquids and to gas.

The specificity of the container of the invention resides in the design of its closure system comprising a flexible lid and a specific type of removable cap.

The flexible lid is hermetically sealed to the container neck (5), so as to protect the aseptic fluid content from contaminants present in the environment and is impermeable to gas. Despite the presence of the lid, spoilage of the content can still happen, e.g. due to incomplete sterilisation of packaging material or product. Spoilage of the fluid content of the container is caused by growth of microorganisms, such as bacteria or fungi (e.g. yeast or moulds) being accidentally present in said product. Most of these organisms produce gas during growth. The lid being impermeable to gas and hermetically sealed to the container neck (5), gas formed in the container by spoilage of its content cannot escape. Therefore, an increase in the pressure inside the container is observed, thus leading to deflection of the flexible lid towards the exterior of the container. Figure 6 represents a container according to the invention, with a flexible lid in the normal position when the content is aseptic (2) and the flexible lid in a deflected position when the product is spoiled (2'). The flexible lid (2') extends in the headspace, contrary to the flexible lid (2). Measurement of the flexible lid deflection can therefore be used as a means for identifying spoilage. In the present invention, the lid thus has the double function of helping preservation of the fluid content of the container and of acting as a spoilage indicator. The flexible lid can be made of any flexible material that is not permeable to gas. The resistance of the material must also be sufficient to avoid rupture under the effect of the pressure changes in the container. In a preferred embodiment, the lid is made of a material comprising metal. In a more preferred embodiment, it is made of a layered material, such as a laminate, comprising at least one metallic layer, most preferably at least one aluminium layer.

The lid must be applied in a removable way to the container neck (5) so that the final consumer can open the container before consumption. However, the lid must be sealed in a sufficiently strong way to avoid any rupture of the seal under the effect of pressure changes in the container, which would lead to inefficacy of the protective and of the spoilage indicator function of the lid. In a preferred embodiment, the flexible lid is glued or thermally sealed to the container neck (5). Using a flexible lid comprising a sealing layer with high affinity to the bottle material enables it to be easily sealed to the container neck (5) by applying heat. Therefore the flexible lid is preferably a laminate comprising at least one metallic layer (preferably an aluminium layer) and at least one sealing layer with high affinity to the material of which the container neck (5) is made.

In a preferred embodiment, the normal pressure in the container (when the fluid content is aseptic) is lower than ambient pressure, so that the flexible lid extends towards the inside of the container. This eases identification of any deflection of the lid when the content is spoiled and thus detection of any spoilage. This allows for detection of even small pressure increase in the container, so that spoilage can be detected at an earlier stage. The container is further provided with a cap. Any type of cap can be used, such as a screw cap or a snap cap. The cap is shaped so as to prevent the inner surface of the cap from entering into contact with the flexible lid when the cap is adapted to the container neck (5) to close the container. This is achieved by providing the cap with a device forming an integral part of the cap, which compresses the neck of the container when the cap is in a closed position and thus prevents the inner surface of the top of the cap from entering into contact with at least part of the surface of the flexible lid. By "compresses", it is meant for the purpose of the present invention that the device enters into contact with the container neck when the cap is closed. A headspace is thus formed over the flexible lid. The pressure exerted by the cap on the container neck can be variable and is not an essential feature of the invention, provided that a headspace is formed between the inner surface of the top of the cap and the flexible lid and provided that such headspace has the required properties in terms of permeability to gas and impermeability to water-like liquids, as described in details below.

The headspace is preferably extending over substantially the whole surface of the flexible lid that is not sealed to the container neck (5). Preferably the height of the headspace is such that the flexible lid can fully deflect under the effect of the inner pressure increase. More preferably the headspace is such that the distance between the inner surface of the top of the cap and the upper surface of the non-deflected lid is of at least 0.5 mm. These specific embodiments further ease the deflection of the lid under the effect of pressure increase in the container and the detection of the lid deflection, by allowing the flexible lid to deflect more freely. The cap is further provided with at least one means for evacuation of the gas present in the headspace (6), such as air. This feature is advantageous in particular because it eases the deflection of the flexible lid under the effect of pressure increase in the container, since such deflection does not require compression of the gas present in the headspace. Such means are advantageously shaped to allow gas such as air to exit the headspace with a sufficient flow, while being impermeable to water-like liquids when the container is shaken or tilted. Impermeability to water-like liquids is particularly useful to avoid any spilling of product out of the container when the container is tilted or shaken by the final consumer before consumption of the fluid content after removal of the flexible lid.

The means for evacuation of the gas from the headspace is in the form of at least one orifice provided in the material of the cap. The orifice is designed to be permeable to gas such as air with a flow of at least 300 ml/min (millilitre per minute), preferably of between 300 and 1000 ml/min, more preferably from 500 to 1000 ml/min, most preferably 750 ml/min at a differential pressure of 50 to 300 mbar, preferably 250 mbar, when the cap is adapted to the container neck (i.e. when it is in a closed position). Design of the orifices to have the above-described gas permeability has a double advantage in terms of efficiency and reliability of a method for detecting spoilage of the container content. First of all, orifices having such gas permeability allow gas present in the headspace to be evacuated so that deflection of the flexible lid under the effect of pressure increase in the container can happen without resistance. Secondly, such orifices render it possible to test the gas impermeability of the container body and of the flexible lid within a reasonable time, while maintaining the cap in place. Being able to test the gas impermeability of the container body and of the sealed flexible lid is advantageous. In cases where gas can exit the sealed container, the lid does not deflect under the effect of content spoilage, so that detection of lid deflection may not allow detection of all spoiled products. Providing a cap having features allowing assessment of the gas impermeability of the container body sealed with the lid therefore contribute to the reliability of spoilage detection. Thanks to the specific gas permeability of the orifices described above, impermeability of the container body and of the sealed lid can even be assessed while maintaining the cap in place. Such assessment is typically carried out by drawing a vaccum in a chamber in which the closed container is placed and by measuring whether the vaccum in the chamber remains stable over time. A cap that would not be provided with orifices such as presently described would have to be removed from the container before assessment of the impermeability of the container body and of the sealed lid. This would highly increase the burden of checking the impermeability of the container body, especially when the safety of a large number of containers has to be tested, for example if all containers of a batch would have to be assessed. It is also an essential feature of the orifice to be small enough to retain liquids with water-like properties when the container is shaken or tilted. In a preferred embodiment, the orifice is characterized by an impermeability to leaking of water-like liquids of at least 200mm water column. For the purpose of the present invention, liquids having water-like properties are defined as any liquid having a surface tension similar to water. Such liquids include for example milk, juices and liquid oral nutritional formulae or supplements.

The required gas permeability and liquid impermeability is preferably achieved by adapting the size of the orifice. The orifice is typically formed of an inner opening (10), an outer opening (1 1 ) and a channel (12) linking the two openings. The smallest of these openings is preferably characterized by its largest dimension being of at most 0.5 mm and by its smallest dimension being of at most 0.2 mm. Any shape can be selected for the openings of the orifice. The inner and the outer orifices may have different shapes and/or dimensions. Figure 6A represents a detailed view of an example of one suitable orifice. A representation of the shape and size of its smallest opening (outer opening) is provided in Figure 5B.

In a preferred embodiment, the at least one orifice is provided in the device that compresses the container neck. More preferably, the at least one orifice is formed by a discontinuity in the compression exerted by the device on the container neck. In this embodiment, the device which compresses the neck of the container when the container is closed is typically shaped such as to form the at least one orifice between said device and the container neck. The device thus preferably has an uneven structure and is provided with at least one cavity so as to provide for a discontinuous compression of the container neck. Therefore orifices will be formed in places where the device does not compress the container neck, each orifice being delimited on one side by the shape of the cavity in the device and on the other side by the surface of the container neck. In a more preferred embodiment, the orifices are not visible from the outside of the container when the cap is closed.

In a preferred embodiment, the cap is provided with a plurality of orifices, preferably at least 5, more preferably at least 10, even more preferably at least 20 orifices. In such case, the orifices will altogether allow gas to exit the headspace with a flow as described above. For example to achieve a gas flow of 750 ml/min at a pressure of 250 mbar when the cap is provided with 20 orifices, the gas flow allowed by each orifice is of at least 37.5 ml/min at a pressure of 250 mbar. The container of the present invention is intended for any fluid product that is aseptically filled. Such products are advantageously food products or beverages. In a preferred embodiment, such product is a nutritional product or a health care product and even more preferably an infant formula. The container of the present invention is particularly suitable for products for most sensitive consumers because it allows for systematic spoilage detection of all individual containers of a production batch, due to the possibility of non-destructive spoilage detection. The present invention therefore considerably improves the safety of aseptic products for most sensitive consumers like infants or patients in hospital. In another aspect the invention provides for the use of a container according to any of the above-described embodiments in a method for detecting the spoilage of its aseptic fluid content. It also relates to a method for detection of the spoilage of the fluid content of a container of the invention. In all uses and methods according to the invention, the container, the closure system, the flexible lid, the fluid content and the cap are as defined in any of the above-described embodiments.

Preferably the method for detecting the spoilage of the aseptic content of the container comprises the step of detecting the deflection of the flexible lid. The detection of the deflection of the flexible lid is preferably carried out by a proximity detection method, more preferably while maintaining the cap in place. A proximity detection method is generally meant as a method for the detection of the presence of nearby objects without any physical contact using a proximity sensor. Proximity sensors can work using diverse mechanisms. The optimal proximity detection method highly depends on the nature of the object to be detected and more particularly depends on the material of which such object is made and thus mainly depends on the material of which the flexible lid is made. Proximity sensors suitable for detection of metal such as aluminium (e.g. inductive sensors) are preferred for the purpose of the present invention when the flexible lid is made of such metal. In a preferred embodiment the spoilage detection method further comprises an incubation step before the step of detecting the deflection of the flexible lid. Spoilage of the fluid content of the product is caused by growth of microorganisms, such as bacteria or fungi (e.g. yeast or moulds) being accidentally present is said product. Most of these organisms will produce gas while growing. Gas will thus be formed and cause pressure increase in the container and deflection of the flexible lid. Microorganisms present in the fluid product grow naturally when the product is stored between the time the container is filled and the time of product consumption. The incubation step can thus consist of storage of the product during a few days, weeks or months, depending on the product, preferably under prescribed storage conditions such as for example ambient temperature and pressure. Alternatively the incubation conditions can be adapted to mimic normal storage within a shorter period of time. In such cases, temperatures higher than ambient temperatures and typically comprised between 30 and 45°C are used. Temperatures such as 37°C, 40°C or 42°C are for example suitable depending on the type of bacteria and/or fungi involved in the product spoilage. At such temperatures, the incubation time is typically comprised between 48 hours and 30 days. These incubation methods are standard and well-known to the person skilled in the art.

Preferably, the spoilage detection method further comprises the step of assessing the gas impermeability of the sealed container body.

In a most preferred embodiment of the invention, the spoilage detection method comprises the steps of

a. aseptically filling a container with an aseptic fluid

b. sealing the container neck (5) with a removable flexible lid

c. adapting over the flexible lid a removable cap provided with at least one device (4), which is designed as integral part of the cap (3), so that

i. the device is compressed on the neck (5) of the container without damaging the flexible lid (2) and prevents the top of the cap (8) from entering into contact with the flexible lid (2);

ii. a headspace (6) is created between at least part of the upper surface of the non-deflected flexible lid (2) and the inner surface (7) of the top (8) of the cap (3);

iii. the headspace is provided with at least one orifice;

iv. the orifice is permeable to gas with a flow of at least 300 ml/min at 50 to

300 mbar differential pressure; and

v. the orifice is impermeable to liquids with water-like properties when the container (1 ) is shaken or tilted.

d. incubating the closed container; and

e. detecting the deflection of the flexible lid.

Preferably such spoilage detection method further comprises the step of assessing the gas impermeability of the sealed container body. This additional step can be carried out between steps c and d, between step d and e or after step e. The container of the present invention can be produced by carrying out a method comprising the step of aseptically filling a container with a fluid product and closing the container with a closure system as described in any of the embodiments of the invention.

Preferably the method for producing a container according to the invention comprises the steps of

a. aseptically filling a container with an aseptic fluid

b. sealing the container neck (5) with a removable flexible lid

i. such device is compressed on the neck (5) of the container without damaging the flexible lid (2) and prevents the top of the cap (8) from entering into contact with the flexible lid (2), so that

iii. the headspace is provided with at least one orifice,

iv. the orifice is permeable to gas with a flow of at least 300 ml/min at 50-300 mbar differential pressure; and

The container, the aseptic product, the fluid content, the flexible lid and the cap are preferably as defined in any of the above-described embodiments.

The step of aseptically filling the fluid content in the container is well-known to the person skilled in the art. Standard methods of aseptic filling can be applied.

The present invention will now be described in further details by the way of the following examples. Example 1

A gas impermeable plastic bottle aseptically filled with a liquid infant formula is provided with the closure system of Figures 1 to 6. The closure system allows for deflection of the flexible lid into the headspace under the effect of pressure increase in the bottle when the liquid infant formula is spoiled.

Example 2 The spoilage of the liquid infant formula contained in the bottle of Examples 1 is analysed by detecting the deflection of the lid (2) in the headspace (6) by proximity detection. An inductive sensor is used to detect the deflection of the flexible lid, which is made of a layered material comprising an aluminium layer.

Claims

A container (1 ), the content of which is an aseptic fluid, said container being equipped with a closure system comprising

a) a removable flexible lid

(2) sealed to the container neck (5) and

b) a removable cap

(3) adapted to the container over the flexible lid and provided with at least one device

(4), which forms an integral part of the cap (3), compresses the neck (5) of the container without damaging the flexible lid (2) and prevents the top of the cap (8) from entering into contact with the flexible lid (2), so that a headspace (6) extends between at least part of the upper surface of the flexible lid (2) and the inner surface (7) of the top (8) of the cap (3)

characterized in that

i) the headspace is provided with at least one orifice,

ii) the orifice is permeable to gas with a flow of at least 300 ml/min at 50 to 300 mbar differential pressure; and

A container according to claim 1 , characterized in that the pressure in the container is lower than ambient pressure.

A container according to claim 1 or 2, characterized in that the headspace extends between the inner surface (7) of the top (8) of the cap and substantially the whole surface of the flexible lid (2) that is not sealed to the container neck (5).

A container according to any one of the preceding claims, characterized in that the distance between the inner surface (7) of the top (8) of the cap and the upper surface of the flexible lid is of at least 0.5 mm.

5. A container according to any one of the preceding claims, characterized in that the orifice is provided in the device compressing the container neck.

A container according to any one of the preceding claims, characterized in that the flexible lid is made of a material comprising metal.

A container according to any one of the preceding claims, characterized in that the orifice is characterized by an impermeability to leaking of water-like liquids of at least 200 mm water column.

A container according to any one of the preceding claims, characterized in that the orifice is formed of an inner opening (10), an outer opening (1 1 ) and a channel (12) in the cap material linking the two openings, the smallest of such openings having its largest dimension of at most 0.5 mm and its smallest dimension of at most 0.2 mm.

9. A container according to any one of the preceding claims, wherein the food product is a nutritional composition or a health care product.

10. Use of a container according to any one of the preceding claims in a method for detecting spoilage of its content.

1 1 . Use according to claim 10, characterized in that said method comprises the step of detecting the deflection of the flexible lid.

12. Use according to claim 1 1 , characterized in that the detection of the deflection of the flexible lid is carried out by proximity detection, preferably while maintaining the cap in place.

13. A method for detecting spoilage of the aseptic content of a container comprising the steps of

a. aseptically filling the container with an aseptic fluid;

b. sealing the container neck (5) with a removable flexible lid;

i. the device compresses the neck (5) of the container without damaging the flexible lid (2) and prevents the top of the cap (8) from entering into contact with the flexible lid (2);

ii. a headspace (6) is created between at least part of the upper surface of the flexible lid (2) and the inner surface (7) of the top (8) of the cap (3); iii. the headspace is provided with at least one orifice;

iv. the orifice is permeable to gas with a flow of at least 300 ml/min at 50 to 300 mbar differential pressure; and

v. the orifice is impermeable to liquids with water-like properties when the container (1 ) is shaken or tilted;

d. incubating the closed container; and

e. detecting the deflection of the flexible lid.

A method for the production of a container according to any one of claims 1 to 9, characterized in that it comprises the step of aseptically filling a container with an aseptic fluid product and closing the container with a closure system as described in any one of claims 1 to 9.

Method according to claim 14, characterized in that said method comprises the steps of

a. aseptically filling a container with an aseptic fluid;

b. sealing the container neck (5) with a removable flexible lid;

i. such device compresses the neck (5) of the container without damaging the flexible lid (2) and prevents the top of the cap (8) from entering into contact with the flexible lid (2);

ii. a headspace (6) is created between at least part of the upper surface of the flexible lid (2) and the inner surface (7) of the top (8) of the cap (3); iii. the headspace is provided with at least one orifice,