Method and apparatus for inerting head space of a capped container

Abstract

A process to reduce oxygen in the head space of non-pressurized containers comprises injecting an inert gas into the container head space and into the cap during the capping process. In an alternative embodiment, inert gas is injected into the caps at one or more points along the conveyance rout to the capping point.

1 ) A method for extending shelf life of a potable liquid in a container sealed by a cap having a top member and a skirt depending from the top member and defining a skirt volume, the container defining a head space above the potable liquid, comprising the step of: 
 a) bringing the container and the cap into a close relationship;    b) injecting an inert gas simultaneously into the container head space and the skirt volume; and    c) sealing the cap on the container with a gas composition in the head space comprising less than about fourteen percent oxygen by volume.    
   
   
       2 ) A method as recited in  claim 1 , wherein the cap initially contacts the container in an inclined orientation during the sealing step (c), and the inert gas is injected at or near the point where the cap and the container initially come into contact during the sealing step (c).  
   
   
       3 ) A method as recited in  claim 1 , wherein the gas composition in the sealed head space is less than about twelve percent oxygen by volume.  
   
   
       4 ) A method as recited in  claim 1 , wherein the inert gas is injected by at least one injector, and the at least one injector injects inert gas into both the container head space and the cap skirt volume.  
   
   
       5 ) A method as recited in  claim 1 , wherein the inert gas is injected by at least a first injector and a second injector, the first injector injecting inert gas into the container head space and the second injector injecting inert gas into the cap skirt volume.  
   
   
       6 ) A method as recited in  claim 5 , wherein the same inert gas is injected by the first injector and the second injector.  
   
   
       7 ) A method as recited in  claim 5 , including a first inert gas and a second inert gas, wherein the first injector injects the first inert gas into the container head space and the second injector injects the second inert gas into the cap skirt volume.  
   
   
       8 ) A method as recited in  claim 1 , further comprising the step of injecting an inert gas into the cap skirt volume prior to the step (a) of bringing the container and the cap into a close relationship.  
   
   
       9 ) A method as recited in  claim 5 , wherein the gas composition in the sealed head space is less than about twelve percent oxygen by volume.  
   
   
       10 ) A method as recited in  claim 8 , wherein the gas composition in the sealed head space is less than about twelve percent oxygen by volume.  
   
   
       11 ) An apparatus for use with a method for extending shelf life of a potable liquid in a container sealed by a cap having a top member and a skirt depending from the top member and defining a skirt volume, the container defining a head space above the potable liquid, the apparatus comprising: 
 a) a pressurized supply of an inert gas;    b) means for injecting the inert gas into the container head space, connected to the pressurized supply of inert gas; and    c) means for injecting the inert gas into the cap skirt volume, connected to the pressurized supply of inert gas.    
   
   
       12 ) An apparatus as recited in  claim 11 , wherein at least one injector is both the means for injecting the inert gas into the container head space and the means for injecting the inert gas into the cap skirt volume.  
   
   
       13 ) An apparatus as recited in  claim 11 , wherein at least one first injector is the means for injecting the inert gas into the container head space, further comprising at least one second injector for injecting the inert gas into the cap skirt volume.  
   
   
       14 ) An apparatus as recited in  claim 13 , further comprising a plurality of second injectors, positioned so as to inject the inert gas into cap skirt volume at more than one location along a route traveled by the caps prior to engaging with and sealing the container.  
   
   
       15 ) An apparatus as recited in  claim 14 , further comprising a second pressurized supply of inert gas connected to the means for injecting inert gas into the cap skirt volume.  
   
   
       16 ) An apparatus as recited in  claim 15 , wherein the first inert gas and the second inert gas differ in chemical composition.  
   
   
       17 ) An apparatus as recited in  claim 11 , further comprising a header block connected to the inert gas supply, and wherein the means for injecting the inert gas into the container head space and the means for injecting the inert gas into the cap skirt volume are connected to the header block.