Electronic Nose Combined With Computer Visions And The Researches In Food Freshness Detection

Nowadays electronic nose (e-Nose) is tending to be intelligent and portable with wider applications in various fields. Besides breath diagnosis of disease, the researches on food freshness detection with e-Noses are more and more published. Aiming at the application of the food freshness detection with electronic nose and combining with the breath detecting research at early stage, this article designed an intelligent electronic nose system to apply in food freshness detection. The contents and originality innovations of the article are as follows:1. The methods and application are explored for the food freshness detection with electronic noses.Research on the characteristic gases that represent the freshness of different types of food. Referring to the literary and the GC-MS experiments, the article determines that the characteristic gases of different types of food. According to the experimental results, the article establishes the primary database of characteristic gases that represent the freshness of food, which improves the standardization of the food freshness detection. Research the effect of food freshness detection with MOS sensors, and select pork, spinaches and oranges to do detection experiments, the experimental results indicate that the MOS sensors have excellent sensitivity and specificity to the volatile gases.2. Design and develop the intelligent electronic nose detecting system in modularization conception.The system has Sensors array and detection module, gaspath module, hardware circuit module and software module according to the functional modules. The Sensors array and detection module includes the MOS sensors array and detection chamber. The article designs a special detecting container for the system, heating gaspath for the gases in low temperature and mass flow controller in the gaspath module. The hardware circuit module includes the micro controller, sensors detecting module and controlling module and user interaction interface module. The software module mainly consists of the controlling programme in micro chip, the controlling and analyzing software in PC and the mobile app with WIFI connection.3. Research on the intelligent identifying method of food freshness detection with e-Nose.Depending on different types of food and the actual detection targets, the article verifies the effect of identification of different types of food with the intelligent electronic nose detecting system, and primarily explore how to identify the type of food with the volatile gases. Pork, spinaches and oranges are selected to do experiments to improve the identification software and verify the effect of the system. And the article separatelily do 15,24 and 27 groups of the three kinds of food, the results indicate that the method can work well.4. Primarily research on the method of identifying the food freshness combined with compuer vision and e-Nose.While achieving the goal of intelligent electronic nose detecting system, this article primarily establishes a computer vision system to explore the application of this technology to enhance the effect of food freshness identification, and verify the effect with 15 groups of pork.Finally, this article also introduces the calibrating experiments for the intelligent electronic nose and uses LDA method to identify the freshness of different types of food. The experimental results indicate that the method has excellent performance in identifying the freshness and food types, the accuracy of the three types of food’s freshness detection to is separately 80%,87.5% and 88.9%. The computer vision is capable of enhancing the effect of freshness identification, combining with the computer vision raises the accuracy of detection of pork to 93.3%.