Functionalized jute with high-water absorption, low thermal conductivity and efficient radiative cooling for the preservation of perishable green vegetables with reduced cold storage energy requirements

Abstract

Jute bags, traditionally used for storing fruits, vegetables and cereals, lack temperature resilience and catch fire, making the contents inside the bag vulnerable to deterioration. In this study, normal jute fibres (NJFs) were strategically modified via a delignification-cum-phosphorylation route to produce phosphorylated jute fibres (PJFs) using low-cost agro-based chemicals. PJFs exhibit a high water absorption capacity and a lower evaporation rate with prolonged moisture retention capabilities. Interestingly, PJFs also show an ultra-low thermal conductivity of 0.076–0.078 W m⁻¹ K⁻¹, slow rate of burning (0.058 cm s⁻¹), high reflectance to light in the IR region (76%) and high thermal stability. PJF bags used for the storage of perishable vegetables, such as coriander leaves, show an extension in shelf life by ∼2 days, along with flame resistance to heat-sensitive vegetables such as chilies on exposure to high temperature. Life cycle assessment (LCA) shows that the production of PJFs generates 49.4% less global warming potential impact as compared to PET production with improved biodegradation within ∼21 days. Further, the utilization of PJFs reduced the time for cold storage of coriander leaves to 8 days, which led to reduced energy requirements and lowered environmental impacts by 11% in the terrestrial ecotoxicity and climate change category. The present study provides a strategic, scalable and green route for the production of functionalized jute bags required for the storage of perishable agricultural harvests, reducing global issues associated with food loss and improving human health and the economy.