电化学传感器水果成熟度检测技术的研究

Study on real-time measurement of fruit maturities using an electrochemical sensor

提出了一种基于电化学乙烯传感器的水果成熟度检测系统,通过实时检测水果释放的乙烯气体浓度来评判水果成熟度。该系统主要由电化学乙烯传感器、微处理器电路、微型真空泵和气室等构成。微处理器电路接收电化学传感器感测到的水果释放乙烯气体产生的电流信号,乙烯气体质量浓度检测结果直接显示在触摸屏上。通过4种质量浓度分别为2.99、4.99、8.01、10 mg·L^(-1)标准乙烯气体响应试验,建立了乙烯气体质量浓度与电化学传感器响应信号之间的定标曲线,乙烯气体质量浓度在0~10 mg·L^(-1)范围内,与电化学传感器响应信号相关系数为0.998 14,理论最低检出限为0.86 mg·L^(-1)。采用水果成熟度检测系统对不同成熟度的苹果释放的乙烯气体质量浓度进行了检测试验,结果表明该系统能对不同成熟度的水果进行有效区分和评判。

In this paper,a measurement system constructed with an electrochemical ethylene sensor for evaluating the fruit maturity was proposed. It consisted of an electrochemical ethylene sensor,a microprocessor circuit,a micro-vacuum pump and a gas chamber,wherein,the microprocessor circuit receiving electric current generated by the electrochemical sensor that used to detect the ethylene gas. The data of measurement of the concentrations of ethylene gas and fruit species displayed on a touch screen. The calibration curve between the ethylene gas concentrations and the response signals from the electrochemical sensor was established by 4 standard concentrations of 2. 99,4. 99,8. 01 and 10 mg·L^(-1) of ethylene gas. The results showed that the correlation coefficient was 0. 998 14 and the theoretical minimum detection limit was 0. 86 mg·L^(-1) in the range of 0 to 10 mg·L^(-1). The actual measurement experiment was performed to detect the concentration of ethylene gas released from apples in different maturities level. The results showed that the measurement system could distinguish and evaluate the ma-turity levels from different fruits.