Controlled gas packaging

Abstract

A method and apparatus for controlled or modified atmosphere packaging of products such as foodstuffs, whereby the product ( 17 ) is weighed prior to or in the packaging machine and regulating the amount of gas inserted into the package in proportion to the weight of the product. User controlled variables may be used to determine the amount of gas to be injected into a package for a given weight or size of package, typically 1.5 to 1.75 liters of Carbon Dioxide per Kg of meat cut depending upon the type of meat, number/size of voids and bag size.

We claim:  
     
         1 . Apparatus for controlled or modified atmosphere packaging of products, including means for weighing a product to be packaged; means for insertion of a product into a package; means for evacuating the package; means for injecting a gas into the package; means for regulating the amount of gas injected based on information on the weight of product from the weighing means and means for sending the package.  
     
     
         2 . Apparatus as claimed in  claim 1 , wherein the weighing means provides an output to a control device such as microprocessor which in turn can be used to control the amount of gas injected into the package.  
     
     
         3 . Apparatus as claimed in  claim 1 , wherein the weighing means forms part of the packaging machine.  
     
     
         4 . Apparatus as claimed in  claim 1 , wherein the weighing means is a weigh station situated prior to the packaging machine.  
     
     
         5 . Apparatus as claimed in  claim 1 , wherein the weighing means is closely associated with the apparatus.  
     
     
         6 . Apparatus as claimed in  claim 1 , wherein the weighing means is associated with a conveyor conveying product to the packaging machine so that the weight of the product is determined before the product reaches the packaging machine.  
     
     
         7 . Apparatus as claimed in  claim 1 , wherein the packaging machine has a manual control to enable the user to set the amount of gas per weight or type of product.  
     
     
         8 . A method of controlling the amount of gas injected into a package by determining the weight or type of product, and automatically varying the amount of gas injected based on the weight of the product.  
     
     
         9 . A method as claimed in  claim 8 , wherein the method involves setting a user determined variable to regulate the desired amount of gas per weight of product, and combining this setting with the weight of the product.