Lignoholocellulose-based biopads from upcycled agri-food byproducts for sustainable clamshell packaging and enhanced strawberry preservation

Mechanical damage and moisture loss during postharvest handling significantly reduce the shelf life of strawberries and contribute to substantial food losses. Expanded polystyrene (EPS) pads are commonly used in clamshell packaging to provide cushioning and moisture management, yet their non-biodegradable nature presents environmental challenges. This study introduces biodegradable lignoholocellulose (LHC)-based biopads as a sustainable alternative, produced from cellulose nanofiber (wood-derived) and various LHC sources, including hemp hurd, onion skin, red wine grape pomace, and hazelnut shell, with chitosan and sodium dodecyl sulfate as functional additives. The biopads were characterized for physicochemical, mechanical, and morphological properties to establish structure-function relationships relevant to packaging applications. They exhibited low densities (11-18 mg/cm³), moderate water vapor absorption (7.8-9.1%), and resilience to high compression forces (74.1-135.3 N at 80% deformation). Microscopy revealed porous, interconnected structures conducive to moisture uptake and cushioning. Based on overall performance, the hemp hurd LHC biopad was selected for packaging validation. Under simulated supply-chain conditions, including vibration (10 Hz, 48 h), cold storage (6 days at 4°C), and ambient holding (24 h at 25°C), strawberries packaged with hemp hurd biopads showed improved firmness and color retention, along with reduced mechanical damage, weight loss, and mold incidence compared with controls. These results demonstrate that hemp hurd-based LHC biopads provide a renewable, biodegradable, and high-performance alternative to EPS, supporting both sustainable packaging development and postharvest quality preservation.