Progress in the study of zein as wall materials for the encapsulation of bioactive compounds: Construction, applications, and prospects

Zein, a value-added product extracted from corn processing byproducts, is widely utilized as a wall material for microencapsulation due to its exceptional hydrophobicity, antioxidant properties, and film-forming capacity. This application significantly enhances the value-added potential and economic benefits of the corn industry chain. This paper reviewed the research progress of zein microcapsules in recent years, focusing on their traditional preparation methods, performance characteristics and application areas. The principles, stages, advantages and disadvantages, and influencing factors of three preparation methods, including antisolvent precipitation, spray drying and electrostatic layer-by-layer self-assembly, were analysed in detail. It is noteworthy that when comparing traditional methods with three emerging technologies (microfluidics, electrospray, and atmospheric cold plasma) the latter demonstrate capabilities for precise control over microcapsule size, single-step multilayer encapsulation, and avoidance of organic solvent-related hazards. Furthermore, the modification mechanisms of zein are elucidated at the molecular level through molecular dynamics, focusing on interactions such as hydrogen bonding, hydrophobic effects, and electrostatic forces. Additionally, this article explores the application prospects of zein-based microcapsules in fields including food, pharmaceuticals, leather, textiles, and agriculture, as well as their roles in improving food texture characteristics, controlled release, antioxidant capacity, and antibacterial properties. The findings indicate that zein microcapsules offer advantages such as simple preparation processes, stable performance, and broad applicability, suggesting promising potential for wider adoption and utilization in diverse fields in the future. • The literature visualization study on zein microcapsules is provided. • The advantages and disadvantages of different preparation methods were compared and analyzed. • Their performances and structural mechanisms are elaborated. • The modification mechanism of zein at the molecular level from the perspective of molecular dynamics was analyzed.