Abstract

PREPARATION OF COLOR-CHANGING PACKAGING MATERIAL FOR MONITORING THE FRESHNESS OF CARICA PAPAYA IN REALTIME

Tanaya S. Mondal*, Savanta V. Raut and Madhavi U. Bhise

Abstract

Anthocyanin, a natural pigment found in red cabbage, can act as a pH sensitive indicator. A novel intelligent packaging material in the form of thin film was prepared by casting and drying a mixed solution of gelatin, carboxymethyl cellulose (CMC) and xanthan gum, to which anthocyanin was incorporated as the pH indicator. This film can indicate the freshness of fruit through color changes due to the gaseous microbial by-product formed in response to the fruit spoilage. Variations in the three film components were investigated using Fourier transform infrared spectroscopy. Furthermore, the film morphology and structure were evaluated using scanning electron microscopy. Xanthan gum enhanced the water resistance of the gelatin- CMC film and also improved the physical properties like light barrier. The improved activity is due to the enhanced immobilization of anthocyanin dye. The gelatin CMC-xanthan gum-anthocyanin (GCX) film showed different color changes in response to different pH buffers. It was also found to be sensitive towards gaseous metabolites. When the film was stored with Papaya at room temperature (RT) and 4oC, it showed a color change from green to pink as the fruit started losing its freshness. Hence, this film can be used in monitoring the freshness of fruits in real time.

Keywords: Intelligent Packaging, Anthocyanin, Xanthan gum, Papaya.