Effects of ethyl maltol on properties of starch-based active packaging: Morphology, volatile release and mold inhibition

Abstract

Ethyl maltol, known for its caramel-like flavor and antimicrobial properties, blends compatibly with baked goods. In this study, ethyl maltol-incorporated starch films were developed as potential active food packaging materials. Films containing 0–10% ethyl maltol were prepared and characterized for their physicochemical, antimicrobial, and barrier properties. Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy confirmed interactions between ethyl maltol and starch, leading to modified thermal properties and enhanced film smoothness. Dynamic mechanical analysis revealed a shift in the relaxation temperature with increasing ethyl maltol content, indicating changes in polymer chain mobility. Water vapor permeability decreased with ethyl maltol incorporation, likely due to reduced hydrophilicity, while oxygen permeability increased, suggesting increased hydrophobicity. Ethyl maltol exhibited antifungal activity against Aspergillus niger, with a maximum inhibition zone of 1.53 mm at 10% loading. When incorporated into starch films, ethyl maltol effectively inhibited fungal growth in butter cake, extending its shelf life by up to three-fold. The controlled release kinetics of ethyl maltol from the films was analyzed using gas chromatography-mass spectrometry (GC-MS), revealing a linear release profile. These results demonstrate the potential of ethyl maltol-incorporated starch films as active, biodegradable food packaging materials with antimicrobial properties and significant shelf-life extension benefits.