Improving the property of a reproducible bioplastic film of glutenin and its application in retarding senescence of postharvest Agaricus bisporus

Bio-based films have a considerable role in protecting the environment and extending the shelf-life of vegetables. Glutenin has good film-forming properties as a biological substrate. However, the mechanical performance of pure glutenin film is far lower than those of traditional films. In this study, tamarind gum and glutenin were blended to improve the mechanical properties of the glutenin film. The blend films were prepared at a tamarind gum/glutenin mixing ratio of 1:0.3, 1:0.4, and 1:0.5 (w/w). The results showed that the mechanical properties of the blend films were ameliorated, especially the tensile strength of the G-TG-2 (glutenin–tamarind gum film), which was 2.7 times higher than that of the glutenin film. Meanwhile, the rigid fracture of G-TG-2 was enhanced, with the elongation at break being as high as 89.2% ± 0.45%. As evidenced by scanning electron microscopic imaging, blend films with excessive glutenin produced a large number of aggregated particles, while the surface of the G-TG-2 film was smooth and compact. Fourier-transform infrared spectroscopy showed that the glutenin and tamarind gum produced strong physical entanglement and noncovalent interactions. Compared with the glutenin film, the hydrophobicity of the blend films was enhanced. The G-TG-2 film with the highest 2,2-diphenyl-1-picrylhydrazyl scavenging rate was used for preserving Agaricus bisporus, which effectively reduced the respiration rate. The color, hardness, quality, and peroxidase and superoxide dismutase activities were well maintained, and the senescence of mushrooms was delayed. Our study not only provided an effective way to preserve mushrooms but also proposed a green and effective bioplastic film with superior properties and simple operating process. The materials included only tamarind gum, glutenin, NaOH, and glycerol, which were simply mixed to promote the application of glutenin, development of the biological packaging industry, and circular development areas.