1440 Timberwolf Drive
PO Box 964
Holland, OH 43528-0964 USA
Oxygen - Container (MOCON, Headspace)
|Sample Type||Required Quantity||Equipment Used|
|Bottles||1||PTI OxyTraq™ system MOCON Ox-tran Oxysense Mocon Headspace|
This procedure measures the permeation rate of oxygen through a container or film using a OxyTraQ™ system, MOCON OX-Tran, Oxysense or MOCON Headspace. The device will be selected based on the scope of the testing and the requirements of the container.
OxyTraQ™ system or MOCON OX-Tran system: Film or Bottle
These systems are used to test the oxygen permeation rate of films or whole packages under steady state oxygen concentrations. The film or package is subjected to a continuous flow of carrier (oxygen-free) gas across the film or through the inside of the bottle. The outside of the bottle or the other side of the film is continually purged with room air or with a gaseous mixture containing a specific % oxygen. This carrier gas passes through a sensor which measures the amount of oxygen in the gas stream. The oxygen the permeates through the package or film is picked up by the carrier gas and carried to the sensor. The level of oxygen detected by the sensor corresponds to the permeation rate of the package or film. The driving force is always high oxygen on the outside and very low oxygen on the inside. Samples need to stay on the device until a steady state equilibrium results allowing for the true permeation measurement to be made.
Oxysense: Bottles Only
Empty or filled containers can be tested. A special dye impregnated "sensor dot" is affixed to the inside of the container. The container is filled with product or flushed free of air and sealed. At predetermined sampling times, a sensor pen is positioned opposite the dot on the outside of the container. A signal is triggered causing the pen to emit light at a predetermined wavelength; this will absorb the light and will fluoresce depending on the O2 concentration. This resulting light is measured by the sensor and the concentration of O2 is reported. This test method can represent real world environments, does not require puncturing the samples, and there is also no limit to the number of times a container can be sampled. This method is suitable for testing oxygen scavenging systems over long periods of time. One concern with this test is that the package cannot interfere with the wavelengths of light energy emitted or fluoresced. This test differs from the OxyTraQ™ or Mocon test in that it measures the build up of O2 in the bottle as it permeates into it over time.
MOCON Headspace: Bottle Only
Whole packages with a small volume of water are sealed with a mechanism that allows for removal of a gas headspace sample. At designated intervals, a small gas headspace sample is withdrawn from the package and injected into the MOCON Headspace device. This device reports the ppm of O2 present and over the course of several months, the oxygen ingress as a function of time is determined. The testing is completed on a set of four sample bottles. This test method has been employed for packages with long shelf lives such as oxygen scavenging packages. The disadvantage of this test method is that it is an intrusive test, since the stopper through which the sample is removed is prone to leaking O2 into the package, compromising the measurement. This test method cannot currently be used to test films.