Effects of gelatine, alginate, glycerol, sorbitol, and flavedo extract on biofilms’ properties

Edible components incorporated into biofilms have demonstrated numerous benefits and promising potentials for diverse applications in food technology. The present work investigated the impact of various film-forming ingredients, including pectin, alginate, gelatine, glycerol, sorbitol, and flavedo extract of Citrus maxima (Burm.) Merr. pomelo on the morphological, mechanical, microstructural, thermogravimetric, antioxidant, and antibacterial properties of films. The PGS 5 film, formulated with 85% pectin solution, 5% gelatine solution, 5% sorbitol, and 5% flavedo extract, exhibited superior morphological characteristics, optimal mechanical properties (tensile strength: 9.87 ± 0.19 MPa; elongation at break: 50 ± 1.39%; and thickness: 0.149 ± 0.003), improved heat resistance, poor optical transmittance, and enhanced scavenging ability for free radicals DPPH (23.76 ± 2.314%) and ABTS (22.71 ± 1.95%). Despite inducing minor structural changes and intermolecular interactions, the supplemented film with 5% flavedo extract demonstrated resistance to various pathogenic bacterial strains. These findings suggested the potential use of the developed PGS 5 film with flavedo extract for food applications.