Characterization and meat freshness application of a serial three-enzyme reactor system measuring ATP-degradative compounds Original Research Article

A serial three-enzyme reactor system which measures hypoxanthine (Hx), inosine (HxR) and inosine 5′-monophosphate (IMP) simultaneously was prepared, characterized for its properties and applied to freshness evaluation of meats. The biosensor system was operated as a flow injection analysis mode and the reactor length combination of 15, 12 and 7 cm for Hx, HxR and IMP, respectively, was selected for a complete reaction between substrate and enzyme. The sequential enzymatic reactions by the system were performed best at 0.05 M phosphate buffer, pH 7.5 and 35°C. The effects of various possible interferants such as amino acids and sodium chloride on the system were investigated. When applied to meat freshness evaluation, the Ki- and H-values obtained by the system agreed well with those obtained by a conventional method (liquid chromatography (LC)).