Characterization of Tri-Phasic Edible Films from Chitosan, Guar Gum, and Whey Protein Isolate Loaded with Plant-Based Antimicrobial Compounds

ABSTRACT

Essential oil containing tri-phasic films of chitosan, guar gum, and whey protein isolate were prepared. Eugenol, carvacrol, and citral were used as the oil phase, either alone or in combination. The addition of essential oils decreased the water vapor transmission rate and tensile strength of the films. CLSM confirmed the presence of essential oil droplets within the biopolymer matrix. XRD analysis indicated that the addition of essential oils altered biopolymer interactions. FTIR analysis suggested alterations within whey protein structure in the presence of essential oils. The essential oil containing films showed good antimicrobial activity, suggesting potential application in food packaging.

KEYWORDS:

• Carvacrol
• chitosan
• citral
• eugenol
• guar gum
• whey protein isolate

Acknowledgments

The authors would like to thank Mr. Susanta Pradhan for technical help regarding confocal laser scanning microscopy images. The authors would like to thank the Interfacial and Nanomaterials Laboratory, Department of Chemical Engineering, NIT Rourkela for extending help towards FTIR analysis of films.

Supplementary material

Supplemental data for this article can be accessed on the publisher’s website at https://doi.org/10.1080/03602559.2018.1466179.