Preparation, physicochemical characteristics and bioactivity evaluation of pitaya peel extract/soy protein nanocomposite film containing zinc oxide nanoparticles by photocatalysis

Abstract

Interactions between components in film‐forming solution affected the physicochemical properties of active packaging. A series of soy protein isolate (SPI)‐based nanocomposite films reinforced with zinc oxide nanoparticles and different pitaya peel extract (PPE) levels were fabricated by photocatalysis. Results showed that the tensile strength, oxygen and water vapor barrier properties, thermal stability and DPPH scavenging activity were substantially improved, but the elongation at break and transmittance decreased with the proportion of PPE increased due to the formation of a more compact film structure caused by the crosslinking of PPE and SPI, particularly at the SPI/PPE ratio of 1:2. However, excessive PPE was not conducive to the integrity and continuity of film structures. The SPI/PPE films had more favorable anti‐bacterial activities against Staphylococcus aureus than Vibrio parahaemolyticus. Therefore, our finding suggested that photocatalytic SPI/PPE nanocomposite film is an interesting alternative to obtain materials with antimicrobial and antioxidant properties. Novelty impact statement Pitaya peel extract (PPE) was added into soy protein isolate (SPI)/ZnO film matrix through photocatalysis. Addition of PPE resulted in compact inner microstructures of the films. SPI‐PPE conjugate greatly improved the antibacterial and antioxidant properties of the films.

Preparation, Characterization, and Application of pH-Response Color-Changeable Films Based on Pullulan, Cooked Amaranth (Amaranthus tricolor L.) Juice, and Bergamot Essential Oil

“…This was because the distribution of betacyanins in the films made the oxygen diffusion path become more complicated [40]. Other researchers also observed that the OP of polysaccharide-based films was significantly reduced by betacyanins from other plant sources [41,42]. Compared to the PL-BEO4 film and PL-CAJ film, the PL-CAJ-BEO2 film and PL-CAJ-BEO4 film showed a relatively lower OP, suggesting that the simultaneous incorporation of BEO and CAJ had a synergistic effect on reducing the OP of pullulan films.…”

Optimizing the edible film production from red pitaya peel powder, konjac glucomannan and kappa carrageenan

“…Beside carbohydrates, red pitaya peel (RPP) contains bioactive compounds and serves as the primary source of betalains, known for their beneficial functions as pigments, antimicrobials, and antioxidants [6,7]. Currently, the utilization of pitaya peel in the production of edible films is primarily limited to extracts such as RPP extract [8][9][10][11] mucilage extract [12]; pectin extract [13,14]; and red pigment extract [15][16][17][18]. Ongoing research is exploring the potential of RPP powder as an additional ingredient for the development of edible films.…”

Preparation and characterization of zinc oxide nanoparticle, its migration, and toxicity evaluation

“…Although ZnO is included in a list of thresholds of exemption for particular use in food packaging, under the code of federal regulation (21 CFR 170.39) (FDA, 2017), there is no distinction between bulk form and nanoform. ZnO‐NPs have been widely used in the food industries for its antimicrobial, antioxidant, and UV‐blocking properties (Jin et al, 2022; Zangeneh Monfared et al, 2022). NPs have a large specific surface area and high surface energy which is responsible for its ability for nanoscale dispersion and interfacial interaction of polymer matrix.…”