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Dielectric barrier discharge (DBD) plasma is a new type of polymer surface modification technology. This study is mainly about the changes in film surface structure and physicochemical properties of whey protein concentrate (WPC)/wheat cross‐linked starch (WCS) composite films after DBD plasma treatment with different plasma parameters. The results show that the proper plasma treatment parameters (400 W to 60 s) can increase the surface roughness, tensile strength, barrier properties, and thermal stability of the edible film and decrease elongation at break and the water contact angle. X‐ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and X‐ray diffraction showed that DBD plasma treatment could increase the content of oxygen‐containing groups on the WPC/WCS film surfaces instead of damaging the internal crystal structure. The results showed that use of proper DBD plasma treatment technology has a positive effect on the mechanical and barrier properties and thermal stability of WPC/WCS films. Practical Application: DBD plasma treatment can improve the mechanical, barrier, and thermal properties of WPC/WCS films without generating any pollution. The DBD plasma can be potentially applied in the enhancement of edible film properties. WPC/WCS films are more environmentally friendly than plastics and can be a replacement for traditional plastics. [ABSTRACT FROM AUTHOR]

The aim of this work is to study the effect of eggshell powder (ESP) on the properties of corn starch (CS) films. It was found that the addition of ESP significantly improved the tensile strength, elongation at break, water vapor and oxygen barrier properties compared to the control film. There was an inductive effect between the C-C bonds on cornstarch skeleton and the O-C-O bond on CaCO3 in the ESP and the number of hydrogen bands increased between starch molecules and ESP particles, which indicated a strong interaction and biocompatibility between the two components. In addition, the organic compounds on the surface of ESP increased the adhesion between CaCO3 particles and CS films matrix. In summary, the ESP, as an enhancement factor, is a good candidate for the development of green food packaging material. [ABSTRACT FROM AUTHOR]

Nano‐titanium dioxide (TiO2) was modified with the surfactant sodium laurate (SL) via ultrasonic microwave‐assisted technology to improve the dispersion of TiO2 in polymer matrices. As revealed by Fourier transform infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy analyses, SL was well adsorbed onto the TiO2 surface through chemical bonding, resulting in SL‐modified TiO2 (TiO2‐SLx). The hydrophobicity and dispersibility of TiO2‐SLx increased significantly compared to unmodified nano‐TiO2. With an increase in the SL concentration from 5% to 15%, the agglomeration of TiO2‐SLx particles decreased considerably, while the particles were more uniform. TiO2‐SLx nanoparticles (3 wt%) were then incorporated into acetylated distarch phosphate/chitosan (ADPS/CS) blended matrices to reinforce the biopolymers. Relative to unmodified TiO2, TiO2‐SLx exhibited a better dispersion capability. Furthermore, as the SL concentration increased, the tensile strength (TS) of the composite films increased, while the elongation at break (E), water vapor permeability (WVP), and solubility all decreased. The composite film containing TiO2‐SL15 (TiO2 modified with 15% SL; ADPS/CS‐TiO2‐SL15 film) displayed the highest TS (31.50 MPa), which was 33.70% higher than that of the pure ADPS/CS film, whereas the ADPS/CS‐TiO2‐SL25 film exhibited the lowest E. Further, the ADPS/CS‐TiO2‐SL15 film displayed the lowest WVP (0.90 × 10−12 g·cm−1·s−1·Pa−1) and solubility (22.91%), which decreased by 30.23% and 26.03% compared to that of the pure ADPS/CS film, respectively. Therefore, SL modification and the use of ultrasonic microwave‐assisted technology are promising for the preparation of nanofillers for biopolymer reinforcement. Practical Application: Nano‐titanium dioxide (TiO2) nanoparticles were modified using the anionic surfactant sodium laurate via ultrasonic‐microwave assisted technology, to improve the dispersion of the TiO2 nanoparticles in polymer matrices. Modified TiO2 nanoparticles were incorporated into acetylated di‐starch phosphate/Chitosan blend films, causing the tensile strength of the composite film to increase and the water solubility and water vapor permeability of the composite film to decrease, making the films suitable for packaging applications. [ABSTRACT FROM AUTHOR]