Arum Widyastuti Perdani, Arima Diah Setiowati, Bambang Purwono, Supriyadi
Colorimetric intelligent food packaging requires an environmentally friendly biopolymer matrix with strong physical properties to retain anthocyanins as sensitive dyes effectively. This retention is crucial for enhancing the colorimetric response used in monitoring food freshness. The objective of this research is to investigate the physicochemical properties of intelligent food packaging films based on the mixing order of pectin and chitosan matrices, along with anthocyanins extracted from rambutan peels. Films were prepared from pectin (P), chitosan (C), pectin-chitosan (PC), pectin-anthocyanins (PA), chitosan-anthocyanins (CA), and various order of mixing film solution consists of pectin, chitosan, and anthocyanins, including pectin-chitosan-anthocyanins (PCA), pectin-anthocyanins-chitosan (PAC), and chitosan-anthocyanins-pectin (CAP). The results demonstrated that the CAP film exhibited favorable tensile strength (TS) of 2.3564 MPa and elongation at break (EAB) of 56.40%. Additionally, the CAP film retained a significant number of total anthocyanins after drying, with a content of 19.01 mg/100g, a total phenolic content (TPC) of 3439.63 mg/100g, and a radical scavenging activity (RSA) of 95.54%. Fourier transform infrared (FTIR) spectroscopy revealed spectral bands in the 3300-3600 cm⁻¹ and 1200-1250 cm⁻¹ regions, suggesting interactions or bonds between anthocyanins and either pectin or chitosan, possibly involving hydrogen bonding or modifications in C–O group structures. The color of the films changed across a pH range of 5–10, transitioning from pink to pale yellow and finally to greenish yellow. Based on these findings, the CAP film is identified as a promising candidate for colorimetric intelligent packaging applications. © 2025 Trans Tech Publications Ltd. All Rights Reserved.
Department of Food and Agricultural Products Technology, Faculty of Agricultural Technology, Universitas Gadjah Mada, 55281, Indonesia; Applied Culinary Arts Study Program, Vocational Faculty, Universitas Negeri Yogyakarta, 55893, Indonesia; Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, 55281, Indonesia
