Rey Ralph, H. VirtucioJoel G, Fernando2023-09-032023-09-0320232170-161X25882082http://hdl.handle.net/123456789/14854The innate nature of polyaniline (PANI) films to visibly change its color from green to blue when exposed to basic volatile amines makes it an excellent candidate for spoilage indication. This is further studied at a low volatile concentrations where slight color changes are detected thru colorimetric image analysis. In this study, we have synthesized polyaniline films on a glass substrate and assessed the performance of the films as food freshness indicator through digital image colorimetry. The synthesized PANI films have an overall homogenous surface that is green in color. Well-dispersed globular nanostructures were revealed in the SEM micrographs. From the results of the Fourier-transform infrared (FTIR) spectroscopy and ultraviolet–visible (UV-Vis) spectroscopy, it was found that the films were in the doped emeraldine oxidation state. The RGB (red, green, and blue) color component values of the PANI film changed correspondingly with the time of exposure to spoiling milkfish samples. Moreover, based on the Pearson product-moment correlation, the green and red components best correlate with the pH values of the milkfish.enPolyanilineColorimetryTotal volatile basic nitrogen (TVBN)food freshnessSensorArticle