Biodegradable Zein-Based Films: Influence of γ-Irradiation on Structural and Functional Properties

• Published in: Journal of agricultural and food chemistry Vol. 57; no. 6; pp. 2529 - 2535
• Main Authors: Soliman, Emad A, Mohy Eldin, Mohamed S, Furuta, Masakazu
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 25.03.2009
• Subjects: Animal, plant, fungal and microbial proteins, edible seaweeds and food yeasts; biodegradable products; Biological and medical sciences; Chemical Phenomena; circular dichroism spectroscopy; Color; crosslinking; films (materials); Food Chemistry/Biochemistry; Food engineering; Food industries; food packaging; Food Packaging - instrumentation; Fundamental and applied biological sciences. Psychology; gamma radiation; Gamma Rays; General aspects; irradiation; Light; mechanical properties; Microscopy, Electron, Scanning; packaging materials; Permeability; roughness; scanning electron microscopy; Solutions; Tensile Strength; ultrastructure; Viscosity; Water; water barrier properties; zein; Zein - chemistry; Zein - radiation effects; viscosity; Zein; color; water vapor permeability; mechanical properties; γ-irradiation; Bass; Viscosity; Edible fish; Film; Color; Mechanical properties; Permeability; Water vapor; Gamma irradiation; γ-Irradiation; Plant protein
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf8032599

Zein, a predominant corn protein, is an alcohol-soluble protein extracted from corn and is characterized by unique film-forming properties. The characteristic brittleness of zein diminishes its usefulness as a structural material. The objective of this work was to study the effect of γ-irradiation on improving the performance of zein films in packaging applications. This goal has been achieved by irradiating zein film-forming solutions with various doses of γ-rays, namely, 10, 20, 30, and 40 kGy at dose rate of 10.5 kGy/h, using a Co60 γ-radiation source. The impact of radiation process on the structural properties has been explored through far-UV CD spectral analysis and scanning electron microscopy. Additionally, viscosity changes that reflect the effect of radiation treatment on degradation and/or cross-linking of protein chains have been measured. However, improvements in the performance of zein films as packaging materials that can be accomplished by radiation treatment have been investigated via monitoring of the color, surface density, roughness, mechanical properties (tensile strength and elongation percentage), water uptake, and water barrier properties. The results indicated that γ-irradiation treatment of the film-forming solution can be used to improve the water barrier properties, as well as color and appearance of the zein films. Moreover, a sterilization effect is considered to be an additional advantage for applying γ- irradiation.