Investigation of Potential Use of Soybean Protein Isolate–Chinese Bayberry Tannin Extract Cross-Linked Films in Packaging Applications

Abstract

The possibility of using commercial bayberry tannin (BT) from a Chinese source as a cross-linker and functional additive to develop soybean protein isolate (SPI)-based films was explored in this study by using the solvent casting method. In particular, the impacts of BT loading on the tensile strength, microstructure, thermal stability, water resistance and antioxidant capacity were fully investigated. The results reveal that SPI incorporated with BT yielded a phenolic–protein hybrid whose relevant films exhibited an improvement in tensile strength of around two times greater compared with native SPI as a result of the formed interactions and covalent cross-links, which could be proven using FTIR spectroscopy. The introduction of BT also led to the compact microstructure of SPI–BT films and enhanced the thermal stability, while the water vapor permeability was reduced compared with the control SPI film, especially at high loading content of tannin. Additionally, the use of BT significantly promoted the antioxidant capacity of the SPI-based films according to DPPH radical scavenging assay results. On this basis, Chinese bayberry tannin is considered a promising natural cross-linker and multifunctional additive that can be dedicated to developing protein-derived films with antioxidant activity for food packaging applications.

Potential of Pinhão husk (Araucaria angustifolia) as a structural reinforcement agent in the properties of edible films of Pinhão flour and gelatin

“…Peaks were identified in the region around 1640 cm −1 , whose region is correlated to the amide group of proteins 69 . According to Ramos et al, 70 the region between 800 and 1150 cm −1 is related to the absorption bands of molecules of glycerol.…”

“…68 Peaks were identified in the region around 1640 cm À1 , whose region is correlated to the amide group of proteins. 69 According to Ramos et al, 70 the region between 800 and 1150 cm À1 is related to the absorption bands of molecules of glycerol. The peaks in this region, mainly at 995 cm À1 were characteristic of alkene groups for C-H binding, 2 were less intense for samples PF3 and PF7.…”

Versatile Epoxidized Soybean Oil-Based Resin with Excellent Adhesion and Film-Forming Property

“…To evaluate the performance of the MHE films, their tensile strength and elongation at break were compared with those of some biomass-based films in literature. ,− According to our survey on literature shown in Figure g, so far, the oil-based films with the highest tensile strength were developed very recently by Zhang’s team . In the study of Zhang’s team, the epoxidized linseed oil was first reacted with CO 2 to produce cyclic carbonate which was then crosslinked by different diamines, resulting in non-isocyanate polyurethanes (NIPUs) films with tensile strength of 19–69 MPa and elongation at break of 15–179% .…”

Potential of Chinese Bayberry (Myrica rubra Sieb. et Zucc.) Fruit, Kernel, and Pomace as Promising Functional Ingredients for the Development of Food Products: A Comprehensive Review

“…However, bayberry tannin can be positively used in food applications. As is well known, tannins have a strong antimicrobial activity, hence, the possibility of using bayberry tannin as a cross-linker and functional additive to develop biomaterials-based films (edible coating) can be studied as done by Liao et al (2022). Additionally, based on its fatty acid profile, bayberry kernel oil may have potential as a healthy edible oil source.…”