Ex-situ fabrication of engineered green network of multifaceted bacterial cellulose film with enhanced antimicrobial properties for post-harvest preservation of table grapes

Abstract

In order to overcome the inherent limitations of pristine bacterial cellulose (BC) as an active food packaging material, this study employs a dual-action approach to ex-situ fabricate a multifaceted green composite of BC through citrus pectin (CP) impregnation and subsequent functionalization with thyme essential oil (TEO) encapsulated CP-TEO active emulsion coating. Among various BC-CP composites studied, BC-CP1 revealed the optimal film formation with homogeneous dense microstructure, enhanced mechanical strength (from 126.37 MPa to 183.24 MPa), and reduced water vapor permeability (WVP) (from 3.69 ×10⁻¹¹ g.m⁻¹.s⁻¹.Pa⁻¹ to 3.33 ×10⁻¹¹ g.m⁻¹.s⁻¹.Pa⁻¹). The WVP was further reduced to 2.69 × 10⁻¹¹ g.m⁻¹.s⁻¹.Pa⁻¹ with the CP-TEO active emulsion coating. The BC-CP1/TEO2 exhibited exceptional antibacterial and antibiofilm characteristics, effective UV-blocking, and improved visible light transmittance. The film demonstrated superior potential in preserving grape quality over 9 days of storage compared to pristine BC and conventional plastic packaging. Thus, the BC-CP1/TEO2 has emerged as an eco-friendly, multi-layered solution for sustainable packaging needs.