IoT-based Cost-Effective Fruit Quality Monitoring System using Electronic Nose
Anindya Bhattacharjee, Nittya Ananda Biswas, Khondakar Ashik Shahriar, Kawsain Bin Salim
TL;DR
The study tackles post-harvest losses from subjective fruit quality evaluation in Bangladesh by introducing a low-cost IoT-enabled electronic nose built from MQ gas sensors (MQ-3, MQ-4, MQ-135) integrated with an ESP32 and DHT22. It develops a threshold-based quality index that combines gas-specific indicators with environmental factors, and provides a bilingual dashboard for farmer-friendly interpretation. Experimental results with bananas demonstrate rising volatile emissions corresponding to ripening and subsequent spoilage, with clearly defined ripening and decomposition thresholds and sensor reliability assessments. The work offers a practical, scalable prototype (~$18) that can reduce losses and be adapted to other fruits and supply-chain contexts.
Abstract
Post-harvest losses due to subjective quality assessment cause significant damage to the economy and food safety, especially in countries like Bangladesh. To mitigate such damages, objective decision-making backed by scientific methods is necessary. An IoT-based, cost-effective quality monitoring system can provide a solution by going beyond subjective quality monitoring and decision-making practices. Here, we propose a low-power, cost-effective fruit quality monitoring system with an array of MQ gas sensors, which can be used as an electronic nose. We track the volatile gas emissions, specifically ethanol, methane, and ammonia, encompassing both ripening and decomposition for a set of bananas. Based on the gas concentration thresholds, we develop a mathematical model to accurately assess fruit quality. We also integrate this information into a dashboard for prompt decision-making and monitoring to make it useful to the farmers. This approach has the potential to reduce economic losses, enhance food safety, and provide scalable solutions for the supply chain.