Effect of conventional, hydrothermal and microwave-assisted extraction of jabuticaba peel pectin on the properties of anthocyanin-based pH-indicator films for monitoring beef freshness

Monitoring food freshness in real time remains a key challenge for food safety and quality assurance, driving interest in intelligent packaging systems that translate processing derived structural changes into functional performance. This study investigated how the extraction method used to obtain pectin, conventional (CE), hydrothermal (HDE), or microwave assisted (MAE), from jabuticaba peel governs the process structure function relationship of pH indicator films incorporating jabuticaba anthocyanins, providing a case study on how an emerging extraction technology can be translated into tunable packaging functionality. Films were prepared by casting, with glycerol, calcium chloride, and anthocyanin extract concentrations fixed across formulations, and all analyses performed in triplicate. The anthocyanin extract displayed strong pH sensitivity, with a characteristic bathochromic shift. The extraction route significantly affected ( p < 0.05) film structure and performance: CE films were more rigid with the highest water content and solubility, whereas MAE films showed greater structural homogeneity, ductility, and colorimetric stability, consistent with their higher galacturonic acid content. In real time monitoring of ground beef stored at 4 degrees C for 5 days, all films detected spoilage related pH increases, but perceptible color change occurred earliest in HDE films, compared with MAE and CE films, showing that the extraction route modulates indicator sensitivity, not only mechanical and barrier properties. These findings establish extraction driven structural tuning as a design strategy for jabuticaba based smart films, offering a transferable framework for linking emerging biomass processing technologies to functional food packaging performance.