Sustainable Utilization of Tea Factory Waste-Derived Microcrystalline Cellulose as Filler Material for Food Packaging Films

Abstract

In the present study, tea waste microcrystalline cellulose (TWMCC) was incorporated into the polymer matrix of poly(vinyl alcohol) (PVA) to improve its properties for food packaging. TWMCC/PVA composite films were prepared using the solution casting method, and the fabricated films were characterized using various analytical techniques for determining chemical, morphological, thermal, mechanical, water resistance, and UV-barrier properties. Strong hydrogen bonding between the hydroxyl groups of PVA and TWMCC forms a dense network structure, resulting in improvement of water resistance, water vapor barrier, UV-blocking properties, and thermal properties, of the films. 5 wt % TWMCC increased the water contact angle of PVA film to 81.54°, while pure PVA film had a lower contact angle of 29.31°. The incorporation of 3 wt % TWMCC increased the tensile strength of PVA film by about 2-fold (from 9.11 ± 1.15 to 18.5 ± 1.93 MPa). PVA composite film containing 5 wt b % TWMCC showed promising performance in extending fruit shelf life by preserving grapes for up to 18 days, while unpacked grapes lost marketability within one week. The findings of the study reveal that microcrystalline cellulose derived from tea industry waste can be used as a suitable filler material for the development of environmentally friendly and sustainable food packaging to minimize the global plastic pollution issue.