Development of pectin/pullulan-based freshness indicator films incorporated with hibiscus anthocyanin and cassava peel cellulose nanofiber-stabilized Pickering nanoemulsion

Abstract

With evolving market demands, there is a critical need to transcend beyond conventional petroleum-based packaging strategies, as their extensive use has led to serious environment-related issues. In response, a new generation of intelligent packaging systems has been developed to enable continuous monitoring of packaged foods and to provide real-time information on their quality and safety status. Within this context, in the present study, multifunctional freshness indicator films of pectin and pullulan were fabricated, wherein anthocyanin rich hibiscus extract (AHE) and tea tree oil loaded Pickering emulsions (PEs) were intricately incorporated into the biopolymeric pectin/pullulan matrix. Furthermore, the developed films were analyzed for their structural, physicochemical, barrier, optical, color stability, ammonia vapor sensitivity and antioxidant activities. X-ray diffraction of the films showed a wide peak at 21.47° (2θ), suggesting specific structural characteristics. Physicochemical analysis showed an increase in thickness (0.17 ± 0.015–0.49 ± 0.015 mm), followed by decrease in moisture content (22.78 ± 0.42% to 15.40 ± 0.28%) and water absorption (60.71 ± 0.50% to 24.62 ± 0.34%). The pectin/pullulan/PE/AHE film exhibited a tensile strength of 8.43 ± 0.48 MPa and an elongation at break of 69.50 ± 3.14%, along with the highest antioxidant activity (43.52 ± 0.23%). When tested for ammonia vapor sensitivity, the films showed significant color change (ΔE > 53), indicating their potential for real time freshness monitoring quality. Furthermore, the indicator films were also evaluated for the real time freshness of chicken meat. In general, this study provides valuable insights in formulating composite films with anthocyanin and PE, contributing to multifunctional packaging systems with enhanced functionality and greater utility in the food business.