Most analytical techniques capable of headspace oxygen detection, such as gas chromatography (GC), are expensive, need a trained operator and require destructive sampling of the packages. As a consequence, much research has been conducted on optical sensors for O2 measurement [3,4] and many commercial luminescence-based O2 sensor systems have been developed, and shown to be as reliable as GC at O2 headspace analysis in food packages [5]. However, such sensors are still a relatively expensive analytical tool [6–8], with the added disadvantage of reversible detection of O2 , and so, in MAP at least, are used mainly for R&D applications.