Characterization of nanocomposite films based on tomato seed mucilage, gelatin and TiO2 nanoparticles
Samira Davoudi, Mohsen Zandi, Ali Ganjloo
Abstract
The aim of the present research was to investigate the interaction effect of incorporating titanium dioxide (TiO 2 ) (0 %, 0.5 %, and 1 %) nanoparticles and manipulating the proportion of tomato seed mucilage (TSM) and gelatin (Ge) (1: 0, 0.33:0.67, 0.67:0.33, and 0:1) on the physical, mechanical, and microbial characteristics of the film. The findings indicated that the incorporation of TiO 2 engendered an augmentation in the surface roughness of the film and an elevation in the film's thickness. The mechanical evaluation results revealed that the incorporation of TiO 2 into the TSM-Ge films significantly enhanced (p˂0.05) the tensile strength (TS), (up to 300 %), an elevation of Young's modulus , while concurrently leading to a reduction in the elongation at break (EB). The incorporation of TiO 2 resulted in a significant enhancement in various properties of the film (p˂0.05), including opacity, contact angle, oxygen permeability (OP), water vapor permeability (WVP), moisture absorption, moisture content , solubility, and swelling. The rise in the proportion of TSM resulted in a concomitant increase in the color differences (ΔE), and yellowness index (YI). Conversely, there was a decrease in the lightness ( L* ) and the whiteness index (WI). Additionally, an increase was found in opacity, solubility, moisture content, WVP, OP, swelling, and moisture absorption. It was observed that films without TiO 2 exhibited no inhibitory effect. However, upon augmenting the concentration of TiO 2 to 1 %, notable inhibitory and lethal effects were observed against various microorganisms, including Staphylococcus aureus , Escherichia coli , Aspergillus niger , and Candida glabrata . The results showed that the TSM-Ge composite film containing TiO 2 , exhibited potential as a viable choice for food packaging susceptible to microbial spoilage.