Utilizing E-nose for detection of mealybug infestation and ripeness of durian.

Background: Mealybugs are major pests that cause sap loss and can significantly reduce the quality and market value of durian fruits. Early detection is essential for effective pest management. This study explores the impact of mealybug infestation on volatile emissions and evaluates the application of a low-cost electronic nose (E-nose) system for early infestation detection and ripeness monitoring.

Methods: A prototype electronic nose (E-nose), equipped with four Grove Multichannel Gas Sensor V2 (GM) series sensors selected from a sensitivity survey of 13 sensors, was developed and tested on "Monthong" and "Kradum Thong" durians under outdoor and indoor conditions. Fruit odor signals were analyzed, and linear discriminant analysis (LDA) was used to assess classification performance.

Results: The E-nose effectively differentiated odor profiles between infested and uninfested fruits and ripeness stages. Infested fruits exhibited a different trend of odor changes during ripening, likely due to stress-induced physiological responses.

Discussion: This is the first study demonstrating the use of an E-nose for durian pest detection and ripeness monitoring. The E-nose shows strong potential as a cost-effective, non-destructive tool for early pest detection and postharvest quality control. Future work will focus on scaling the technology with robotic platforms for large-scale monitoring in farms and storage facilities.