Sesame protein isolate based bionanocomposite films incorporated with TiO2 nanoparticles: Study on morphological, physical and photocatalytic properties

In this study, sesame protein isolate (SPI) based bionancomposite films containing TiO2 nanoparticles (1, 3 and 5%w/w) were produced by casting method. The success of formation of new interactions between SPI chains and TiO2-NPs was confirmed by FT-IR results. FE-SEM morphology observation, revealed the uniform dispersion of NPs at the concentrations lower than 3%. Aggregation of TiO2-NPs accrued at level of 5% and caused to decrease the integrity of SPI chains as approved by XRD analysis. Water vapor transmission rate and water solubility decreased and tensile strength, water contact angle and opacity increased by addition of 3% TiO2. But adverse effects on mechanical and water barrier properties were observed when TiO2 content reached to 5%. Evaluation of the photocatalytic activity of bionanocomposites indicated that SPI-TiO2 5% films is able to scavenge 10.96% of atmosphere oxygen over a 6 h period. Photodegradation studies indicated that after 120 min of UV irradiation, over 72.68% of methylene blue dye (10 mg L-1) was decolorized with 64 cm(2) of the bionanocomposite films. This research explored the potential of SPI-TiO2 bionanocomposite films for food active packaging applications and photodecolorization purposes.