Study on Biodegradable Chitosan-Whey Protein-Based Film Containing Bionanocomposite TiO 2 and Zataria multiflora Essential Oil

• Published in: Journal of food quality 2020-09, Vol.2020, p.1-11
• Main Authors: Gohargani, Maryam, Lashkari, Hannan, Shirazinejad, Alireza
• Format: Article
• Language: English
• ISSN: 0146-9428; 1745-4557
• DOI: 10.1155/2020/8844167

In our research, a composite film of whey protein isolate (WPI)/chitosan incorporated with TiO 2 nanoparticles (NPs) and essential oil of Zataria multiflora (ZEO) was developed. The resulting composite films were evaluated by FTIR, SEM, and XRD, and also the physicochemical characteristics including color, mechanical properties, swelling ratio, and water vapor permeability (WVP) were studied. SEM graphs exhibited that the samples had a uniform and homogeneous structure where TiO 2 NPs and ZEO were well dispersed. FTIR and XRD findings also show that the hydrogen bonds and hydrophobic interactions are the main interactions between the composite WPI/chitosan and TiO 2 . The crystalline nature of the composite samples increased with the increase of NP content. Nevertheless, ZEO had an insignificant effect on the functional groups and the crystallinity of composite samples. The film visual characterization revealed that, by adding and increasing the TiO 2 and TiO 2 -ZEO, sample lightness and opacity significantly increased. Additions of TiO 2 remarkably ( p < 0.05 ) improved the water vapor and mechanical properties of composite samples, although the loading of ZEO, regardless of TiO 2 incorporation, led to a considerable decrement of these properties. Furthermore, composite films containing ZEO combined with 2% of TiO 2 compared with 1% of NPs blended with ZEO had strong antimicrobial properties against Staphylococcus aureus , Escherichia coli , and Listeria monocytogenes . Generally, the findings proposed that the addition of TiO 2 reinforces the properties of composite films with a synergistic effect of ZEO loading on the antibacterial ability, by which the resulting biodegradable composite samples can be used as a food active packaging material.