Physical, Barrier and Antimicrobial Properties of Sodium Caseinate-based Edible Film Containing Hemp Seed oil

Biodegradable edible bioplarmers are the best alternatives to synthetic plastics. In this study, sodium caseinate edible films containing different levels of hemp seed oil (10, 20 and 30% w/w) was produced and their physical, barrier and antimicrobial properties were investigated. By adding hemp seed oil up to 30% (w/w), the thickness, transparency, and solubility of films decreased, and the contact angle increased. The permeability to water vapor was reduced from 76.4×10-11 to 5.1×10-11 g m-1s-1 Pa-1, and oxygen permeation was increased from 11 to 28.3 cm3μm cm-2 day-1 Kpa-1 by addition of hemp seed oil. The disk diffusion method was used to investigate the antimicrobial effect of sodium caseinate film containing hemp seed oil on three pathogenic bacterial strains including Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The largest inhibitory diameter for S. aureus, E. coli, and P. aeruginosa was 31.28, 19.05 and 15.40 mm, respectively. As a result, sodium caseinate films containing hemp seed oil has the most effect on gram-positive bacteria. The results revealed that that adding hemp seed oil improves the physical, barrier and antimicrobial properties of sodium caseinate-based films and coatings.