METHOD AND DEVICE FOR FILLING AND CLOSING A CONTAINER, AND CONTAINER OBTAINED WITH THIS METHOD

Abstract: A method for filling and closing a container comprises the steps of: (a) providing an open container and placing thereof such that the mouth opening of the container is situated at the top; (b) filling the open container with product for packaging, for instance food or a drink, such that a space remains between the surface of the product and the mouth; (c) introducing into said space a chosen quantity of sterile liquid nitrogen; (d) placing a cover loosely on the mouth rim and maintaining the loose placing of the cover on the mouth rim for a chosen time interval; and (e) sealingly coupling the peripheral zone of the cover to the mouth rim zone of the container.

Description: METHOD AND DEVICE FOR FILLING AND CLOSING A CONTAINER, AND CONTAINER OBTAINED WITH THIS METHOD The invention relates to a method for filling and closing a container. It is an object of the invention to cause the filling and closing of a container, in particular for food or a drink, to take place such that the danger of bacterial contamination of the content of the can is limited to a minimum during filling and closing. It is a further object of the invention to cause the filling and closing of a can to take place such that the oxygen content of gas present in the can is considerably reduced. In respect of the above objectives, the invention provides a method for filling and closing a container, comprising the steps of: (a) providing an open container and placing thereof such that the mouth opening of the container is situated at the top; (b) filling the open container with product for packaging, for instance food or a drink, such that a space remains between the surface of the product and the mouth; (c) introducing into said space a chosen quantity of sterile liquid nitrogen; (d) placing a cover loosely on the mouth rim and maintaining the loose placing of the cover on the mouth rim for a chosen time interval ; and (e) sealingly coupling the peripheral zone of the cover to the mouth rim zone of the container. Otherwise than in known methods, the liquid nitrogen introduced into the can ensures during its boiling evaporation that a gas flow takes place which is directed outward and moves through the gap partly caused by this gas flow between the mouth rim of the can and the cover laid loosely thereon. This effectively prevents bacterial contamination by germs in the environment. These are blown away from the access to the can by said gas flow. By making use of a sufficient quantity of liquid nitrogen the air initially present in the container can be effectively expelled by the evaporation of the nitrogen. The oxygen content in the can is hereby effectively reduced. Particularly in respect of the wish to prevent oxidation of foodstuffs by oxygen, this is a very desirable effect of the invention. The method can have the particular feature that the can according to (a) is a metal container. This latter method is preferably embodied such that the coupling according to step (e) takes place by seam-folding. In the most usual cans the method can be embodied such that the chosen quantity according to step (c) lies in the order of 1-10 droplets. A very practical embodiment of the method according to the invention, which lends itself particularly well to implementation in an automatically operating device, has the special feature that the chosen time interval corresponds with the time in which the container is transported from a station in which step (d) is performed to a station in which step (e) is performed. The method according to the invention as specified above can be performed with a for instance automatically operating device for filling and closing a container, which device comprises: means for providing an open container and placing thereof such that the mouth opening is situated at the top; means for filling the open container with product for packaging, for instance food or a drink, such that a space remains between the surface of the product and the mouth; means for introducing into said space a chosen quantity of sterile liquid nitrogen; means for placing a cover loosely on the mouth rim and maintaining the loose placing of the cover on the mouth rim for a chosen time interval ; and means for sealingly coupling the peripheral zone of the cover to the mouth rim zone of the container. The invention further relates to a container filled with product, for instance food or a drink, and a certain quantity of nitrogen gas, obtained by applying the method in accordance with any of the methods as specified above. The invention will now be elucidated with reference to the annexed drawings. Herein: figure 1 shows a schematic representation of a known method for filling and closing a container; and figure 2 shows a representation corresponding with figure 1 of a method according to the invention. Figure 1 shows in a first stage a metal container 1 consisting of a bottom (not shown) and a standing body. This has at its top a mouth opening 2 with a mouth rim 3. After transport as according to an arrow 4, filling of the can 1 with food product 6 takes place as according to arrow 5. As will be apparent, a certain space 7 remains free between the surface of the product and the mouth 3. After further transport a quantity (for instance several drops) of liquid nitrogen 8 are applied to surface 6 via a dispensing device 7. This nitrogen has a temperature of almost -200 β C and in these free conditions is in a state in which the liquid boils and thereby evaporates rapidly while releasing gaseous nitrogen. From a stack 9 of covers 10 a cover is then placed onto mouth rim 3 and sealingly connected to mouth rim 3 by rotation 11 through a schematically designated seam-folding device 12. It will be apparent that while in this manner a certain pressure is created in the filled container which can contribute for instance to the total rigidity of the filled container, penetration into the container of germs from outside is in no way prevented and oxygen is not expelled. It is noted that the transport between dispensing device 7 and seam-folding device 12 will take some time and that the dangers referred to occur during this period. In contrast to figure 1, figure 2 shows that a cover 10 is temporarily placed loosely on mouth rim 3 , whereby gaseous nitrogen can escape as according to arrows 13 via the gap 14 which is created partly by the nitrogen pressure in space 7 after cover 10 has been loosely placed. Bacterial contamination is effectively prevented hereby and air, and therewith oxygen, present in space 7 is expelled. Only after expiry of a chosen time interval does a seam-folding operation in accordance with the last illustration of figure 2 take place. It is noted that the invention is of course not limited to a metal embodiment of the container and/or the can. Glass containers for instance with screw covers or the like also fall within the scope of the invention. It is also noted generally that the quantity of liquid nitrogen used according to the prior art of figure 1 will in general be smaller than in the configuration of figure 2 in which the teaching of the invention is applied. According to the invention a part of the nitrogen must in any case evaporate and serve to generate an effective gas flow which prevents bacterial contamination and expels oxygen. It is finally noted that, in a device in which the method of figure 2 is implemented, the distance between the station where the covers are laid on loosely and the station where the covers are seam-folded into place in combination with the transporting speed according to arrow 4 corresponds with a desired chosen time for which the liquid nitrogen is able to perform its described action, for instance such that after the seam- folding a certain amount of liquid nitrogen still remains which can subsequently evaporate in order to effect a certain overpressure in the filled container. *****

Claims: CLAIMS 1. Method for filling and closing a container, comprising the steps of: (a) providing an open container and placing thereof such that the mouth opening of the container is situated at the top; (b) filling the open container with product for packaging, for instance food or a drink, such that a space remains between the surface of the product and the mouth; (c) introducing into said space a chosen quantity of sterile liquid nitrogen; (d) placing a cover loosely on the mouth rim and maintaining the loose placing of the cover on the mouth rim for a chosen time interval ; and (e) sealingly coupling the peripheral zone of the cover to the mouth rim zone of the container. 2. Method as claimed in claim 1, wherein the can according to (a) is a metal container. 3. Method as claimed in claim 2, wherein the coupling according to step (e) takes place by seam- folding. 4. Method as claimed in claim 1, wherein the chosen quantity according to step (c) lies in the order of 1-10 droplets. 5. Method as claimed in claim 1, wherein the chosen time interval corresponds with the time in which the container is transported from a station in which step (d) is performed to a station in which step (e) is performed. 6. Device for filling and closing a container, which device comprises: means for providing an open container and placing thereof such that the mouth opening is situated at the top; means for filling the open container with product for packaging, for instance food or a drink, such that a space remains between the surface of the product and the mouth; means for introducing into said space a chosen quantity of sterile liquid nitrogen; means for placing a cover loosely on the mouth rim and maintaining the loose placing of the cover on the mouth rim for a chosen time interval ; and means for sealingly coupling the peripheral zone of the cover to the mouth rim zone of the container. 7. Container filled with product, for instance food or a drink, and a certain quantity of nitrogen gas obtained by applying the method as claimed in any of the claims 1-5. *****

Inventors: KAMP-STROEKEN MARIA CORNELIA H, SAVRIJ DROSTE FRED WILLEM, KAMP-STROEKEN, MARIA, CORNELIA, HENDRIKA, SAVRIJ DROSTE, FRED, WILLEM
Applicants: IMPRESS METAL PACKAGING BV, KAMP STROEKEN MARIA CORNELIA H, SAVRIJ DROSTE FRED WILLEM, IMPRESS METAL PACKAGING B.V., KAMP-STROEKEN, MARIA, CORNELIA, HENDRIKA, SAVRIJ DROSTE, FRED, WILLEM
Application year: 1997
Main classification: B65B31
IPC codes: B65B31