Development, characterization, and antioxidant evaluation of corn starch‐based composite films containing tea polyphenols

Abstract

Corn starch/polyvinyl alcohol (PVA) composite films containing different concentrations of tea polyphenols (TP) were fabricated by casting. Scanning electron microscopy and atomic force microscopy images showed that when the TP content was less than 8%, the films were relatively uniform, but with increasing TP concentration, the films became rougher and uneven. Fourier transform infrared, 13C nuclear magnetic resonance, and X‐ray diffraction techniques were used to investigate the interactions between TP, starch, and PVA. The incorporation of TP deepened the color and increased the opacity and solubility of the films. The tensile strength and elongation at break first increased and then decreased with increasing TP content. Furthermore, the addition of TP increased the antioxidant activity of the films, specifically, their ability to scavenge 2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐azinobis (3‐ethylberizothiazoline‐6‐sulfonic acid). The addition of TP can effectively enhance the performance of starch composite films and their potential for application in antioxidant food packaging.

Effect of hyperbranched poly(trimellitic glyceride)/oxidized starch composite sizing agent on the adhesion of polyester yarns

“…XRD patterns of PTG/OS composite films are illustrated in Figure 3. As can be seen from Figure 3, OS and PTG/OS films have strong diffraction peaks at 2 θ = 5.5, 14.8, 17.0, 19.7, 22.0, and 23.9°, which belong to B‐type crystal 20,21 . It indicates that the addition of PTG does not change the crystal type of oxidized starch films.…”

“…As can be seen from Figure 3, OS and PTG/OS films have strong diffraction peaks at 2θ = 5.5, 14.8, 17.0, 19.7, 22.0, and 23.9 , which belong to B-type crystal. 20,21 It indicates that the addition of PTG does not change the crystal type of oxidized starch films. Crystallinity of OS, PTG-1/OS, PTG-2/OS, and PTG-3/OS films calculated by Jade 6.0 are 17.4%, 16.5%, 15.6%, and 14.2%, respectively.…”

Properties of Starch‐Based Nanocomposites with Starch‐Coated ZnONP Obtained by Flat‐Die Extrusion

“…(2022) also reported this effect for zinc oxide nanoparticles, which has been attributed to a crystalline quality. [ 59,60 ] Once ZnONP has been incorporated, a decrease in the transmittance of the different nanocomposites can be seen ( Table 2 ). It might be due to the hindrance of light passage due to the dispersion of the nanoparticles in the TPS matrix.…”

“…[63] According to the literature, this composite could be an excellent UV-A and UV-B shielding agent. [59,64]…”

Effect of addition of pullulan on the properties of native/waxy corn starch‐based films

“…The color and transparency of films are important indicators to determine the appearance of films and consumer acceptance (Yu et al, 2022). Higher absorbance values in films correspond to increased opacity (Fu et al, 2022).…”