Rapid evaluation of mold deterioration in maize using GC-IMS

Maize is highly susceptible to mildew during storage due to its rich nutrient content and hygroscopicity, posing significant risks to food safety and quality. This study employed gas chromatography-ion mobility spectrometry (GC-IMS) for the non-destructive detection and early identification of volatile organic compounds (VOCs) in stored maize. Six key biomarkers-propan-1-ol, hexanal, propanal, nonanal, butan-2-one, and isobutanol-were identified as reliable indicators of initial mold development. By integrating VOCs fingerprinting with principal component analysis (PCA) and heatmap clustering, maize samples were categorized into four distinct stages of mold severity. Finally, the GC-IMS classification method was verified by traditional methods, which showed a high degree of consistency with the traditional storage quality parameters, including fatty acid value and total plate count. These results confirm that GC-IMS is an effective tool for the rapid, on-site monitoring of maize storage conditions, enabling timely interventions to reduce postharvest losses and strengthen food safety management.