Probing sustainable cross-linked quince seed mucilage–sodium alginate biocomposite hydrogels through the development of biodegradable films

Abstract

Biocomposite hydrogels based on quince seed mucilage (QSM) and sodium alginate (SA) incorporated with crosslinkers (ZnO, CaCl₂ and NC) were developed and characterized. Biocomposite hydrogels were characterized for their rheological, structural and thermal properties. Hydrogels with a QSM-to-SA ratio of 80 : 20 and CaCl₂ as a crosslinker agent exhibited more elastic character and stronger gelation, as revealed by rheological studies, and improved structural and thermal properties, as revealed by Fourier transform infrared spectroscopy and differential scanning calorimetry. Hydrogels were further used for the development of films. The prepared biocomposite films were characterised for thickness, tensile strength (TS), water vapour transmission rate (WVTR) and oxygen transmission rate (OTR), biodegradability, instrumental color and antimicrobial activity. Significantly higher TS and lower WVTR and OTR (P ≤ 0.05) were observed in the biocomposite films with CaCl₂ as a crosslinker agent. Biocomposite films with NC as a crosslinker agent exhibited significantly higher instrumental color parameters. Films incorporated with NC showed lower biodegradation by the soil burial test. Films with ZnO as a crosslinker agent exhibited greater inhibitory effect against Aspergillus niger and Rhizopus stolonifer. Overall, biocomposite films with an 80 : 20 ratio of QSM to SA and CaCl₂ as a crosslinker agent as food packaging can provide better protection to extend the food shelf life.