Harnessing HP-β-CD in zein edible coatings for enhanced sensitive fruits preservation

Zein, a natural biodegradable protein, is a promising candidate for developing edible packaging to replace petrochemical-based materials food storage materials. However, its brittleness limits its standalone application. To overcome this, we incorporated 2-hydroxypropyl-beta-cyclodextrin (HP-β-CD) as a functional additive in zein biocoatings, leveraging its interaction with hydrophobic amino acids. We investigated how HP-β-CD affects zein aggregation at different temperatures, ethanol and zein concentrations. Results indicated that zein aggregation decreases with the introduction of HP-β-CD, leading to higher zein solubility. Optimized zein dispersions were utilized to prepare zein films, adding PEG 400 as a plasticizer. The impact of HP-β-CD on the physicochemical and structural properties of zein films was evaluated through orthogonal techniques. HP-β-CD improved the surface and barrier properties, reducing light transmission and water permeability by creating a denser matrix with improved structural integrity. Additionally, zein/HP-β-CD dispersions were directly applied to strawberries via dipping, forming coatings that extended shelf life, highlighting their potential as sustainable alternative to plastic food packaging. As many edible coatings require complex processing and functionalization with active ingredients, which are unnecessary in this case, this strategy offer exciting opportunities for improved food preservation across a broader range of applications, suggesting the need for further investigation.