1.1 The objective of this test method is to determine the carbon dioxide (CO
2
) loss from plastic beverage containers after a specified period of storage time.
1.2 Factors contributing to this pressure loss are volume expansion and the gas transport characteristics of the package including permeation and leakage.
1.3 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
====== Significance And Use ======
Two procedures, A and B, are outlined in this test method. Procedure A is used most often for development of various beverage container designs to determine the functional characteristics of the package in regard to shelf life. Procedure B is recommended for use in beverage filling operations as a quality control tool in maintaining the desired CO
2
fill pressure. A loss of CO
2
will affect product taste.
5.1.1 Procedure A involves the use of sensitive pressure and temperature monitoring equipment where a high degree of accuracy is essential, for example, a micro-pressure transducer and thermocouple for measuring pressure and temperature of the package in a closed system. Alternatively, this procedure may also use bottles closed with roll-on aluminum caps containing rubber septums. The septum is pierced with a hypodermic needle attached to a pressure transducer to obtain pressure readings. This procedure should be confined to laboratories that are practiced in this type of analytical testing.
5.1.2 Procedure B is more widely used when measuring the carbonation level of the package due to the simplicity of the technique. A simple Zahm-Nagle pressure assembly or Terris CO
2
Analyzer is utilized.