A chromogenic sensor array for boiled marinated turkey freshness monitoring

A chromogenic array for monitoring boiled marinated turkey meat freshness in a modified packaging atmosphere (30% CO2, 70% N2) has been developed. The chromogenic array was combined with commodity tools such as digital camera and Photoshop to extract and analyse the colour changes. The array was composed of 16 sensing materials prepared through the combination of 13 indicators (including pH indicators, nucleophilic sensing dyes, etc.) and three different inorganic supports (i.e., UVM-7, alumina and silica gel). The chromogenic data obtained from the array showed characteristic fingerprints for each sampling day (0, 3, 10, 17, 24, 31, 38 and 45 days post-package). Statistical analysis by HCA of the chromogenic data allowed classifying the samples as “fresh”, “not fresh” and “not edible”. Besides, microbiological and sensorial determinations on the packaged samples were also carried out. From these studies a shelf life of 38 days at 4 °C was determined. Colour differences from the chromogenic array were employed to create PLS models for aerobic mesophilic bacteria count, sensory score and storage time with quite good results.