Extraction and characterization of biopolymers from rice bran oil cake: Development of antimicrobial edible coating for extending shelf-life of strawberry fruit

Recent research has focused extensively on extracting polysaccharides from plant sources due to their potential applications across various fields. Several underutilized agricultural by-products from oil industries, such as rice bran oil seed cake, have emerged as promising sources of polysaccharides that can be utilized for applications in agriculture, food production, and pharmaceuticals. The present study explored the biopolymers’ vital functional and antimicrobial properties derived from rice bran oil seed cake. The pH of the solution during the extraction process was optimized to assess its impact on the yield of aqueous extract. Notably, the maximum yield was achieved at pH 6.5 (86.39 ± 0.23%). The nanoscale particle size (265.1 ± 5.06 nm), polydispersity index (0.384), and zeta potential (−45.9 ± 0.25 mV) confirmed the stability of the extract. Moreover, the spray-dried extract biopolymer powder exhibited excellent industrially relevant techno-functional properties, including water-holding capacity (7.08 ± 0.4 g/g), oil-holding capacity (4.32 ± 0.6 g/g), emulsifying capacity (93.50 ± 0.77%), emulsifying stability (95.65 ± 0.36%), solubility (90.32 ± 1.67%), and foaming capacity (14.12 ± 0.31%). Using the powder, a nanoemulsion was prepared to coat strawberry fruits, revealing the shelf-life extension capacity of the nanoemulsion against bacteria, yeast, and mold. Based on these findings, the spray-dried biopolymer powder of rice bran oil seed cake extract could potentially be utilized as a functional ingredient in various food product formulations.