An active edible coating based on cellulose nanofiber stabilized Pickering emulsion: Toward prolonging the shelf life of strawberries

Abstract

This study presents the development of an active edible coating based on TEMPO-oxidized cellulose nanofibers (TOCNFs) derived from rice husk, functioning as both an encapsulation carrier and a stabilizer for Pickering emulsions containing lavender essential oil (LEO). Increasing LEO and TOCNF concentrations improved encapsulation efficiency (44 to 75) and loading capacity (14 to 22). TOCNFs exhibited amphiphilic behavior and reduced interfacial tension from 58.09 +/- 0.03 to 40.12 +/- 0.05 mN/m that enhanced the formation of stable emulsions. Higher TOCNF concentrations led to smaller droplet sizes, a decrease in zeta potential, and prevention of creaming index over 28 days of storage. The optimized formulation (1 TOCNF and 50 LEO) showed excellent stability under varying temperature, pH, and salt conditions, indicating resistance to environmental stresses. The TOCNF/LEO emulsions were formulated using a sage seed mucilage solution and applied as a coating for strawberries stored at 4 degrees C. In addition, the formulated emulsions demonstrated antifungal activity against Aspergillus spp. and Penicillium spp., with minimum inhibitory concentrations of 1700 and 2000 & micro;g/mL, respectively. Compared to uncoated samples, application of the coating on strawberries stored at 4 degrees C effectively delayed quality deterioration, including weight loss, pH changes, firmness reduction, and microbial growth over a 9-day period. Overall, this study highlights the dual functionality of TOCNFs in stabilizing bioactive emulsions and delivering antimicrobial effects. The developed system offers a sustainable and efficient approach for food preservation, utilizing agricultural waste to produce a high-performance, environmentally friendly edible coating for extending the shelf life of fresh produce.