Freshness Estimator for Fruits and Vegetables Using MQ Sensors

To understand the freshness of fruits and vegetables, there is always a necessity to build a device that can automate the process of detecting the freshness. The objective of this paper is to build a device that measures the quality of fruit and vegetables and provides an output based on its edibility. Arduino UNO (microprocessor) along with MQ2, MQ4 (gas sensors Mĭngăn Qǐ lai 2, 4) and IR (Infra-Red) sensors are used to detect the concentration of Methane (CH
4
) and Ethylene (C
2
H
4
) in ppm (Parts Per Million). It was found that the excess ripening after which the fruit starts decomposing has a concentration of 300ppm (Ethylene) for all fruits and vegetables. The decomposition results in producing trace amounts of Methane gas, which is also detected using the MQ4 sensor. With all these constraints, the result is calculated by the microprocessor and is displayed in a 16x2 LCD display. The testing process of the device involved many fruits and vegetables. In this work two common fruits (Mango, Banana) and a common vegetable (Tomato) was deeply analyzed and found that the concentration of Ethylene is very much higher than 300 ppm in the fruits or vegetables which are highly decayed and are considered as unfit for the human consumption. It was also found that the ppm curve with respect to time axis derived from the sensor shows a very less deviation for the highly fresh fruits or vegetables. This device can be implemented in all food-based industries where there is a necessity to compute the freshness of fruits and vegetables. The simplicity and cost-efficiency of the device makes it a perfect product that can be used by everyone.