Characterization and Differentiation between Olive Varieties through Electrical Impedance Spectroscopy, Neural Networks and IoT

Abstract

Electrical impedance has shown itself to be useful in measuring the properties and characteristics of agri-food products: fruit quality, moisture content, the germination capacity in seeds or the frost-resistance of fruit. In the case of olives, it has been used to determine fat content and optimal harvest time. In this paper, a system based on the System on Chip (SoC) AD5933 running a 1024-point discrete Fourier transform (DFT) to return the impedance value as a magnitude and phase and which, working together with two ADG706 analog multiplexers and an external programmable clock based on a synthesized DDS in a FPGA XC3S250E-4VQG100C, allows for the impedance measurement in agri-food products with a frequency sweep from 1 Hz to 100 kHz. This paper demonstrates how electrical impedance is affected by the temperature both in freshly picked olives and in those processed in brine and provides a way to characterize cultivars by making use of only the electrical impedance, neural networks (NN) and the Internet of Things (IoT), allowing information to be collected from the olive samples analyzed both on farms and in factories.

Development of a New Control System for a Rehabilitation Robot Using Electrical Impedance Tomography and Artificial Intelligence

“…Thanks to its small size of 4.1 cm × 2.0 cm, we can easily mount it anywhere. As part of the data input for the analysis, a PmodIA impedance analyzer with an integrated AD5933 is used to measure the impedance between two points [ 27 ].…”

“…Other SMA connectors capture the frequency response and transmit it to the ADC. The sampled data undergo a discrete Fourier transform (DFT), after which the real and imaginary components of the outcome are processed within the on-chip data registers [ 27 , 28 ]. Using I2C interfaces, we can communicate with a microcontroller, such as Arduino, and extract data.…”

Detection of Salt Content in Canned Tuna by Impedance Spectroscopy: A Feasibility Study for Distinguishing Salt Levels

“…EIS has been used for assessing food quality and has shown a high potential for real-time use because changes in the complex impedances of food provide information about its chemical composition and help to follow changes in its state [ 10 ]. Thus, EIS has been extensively used to characterize milk [ 11 ] and yogurts [ 12 ]; to detect the quality and adulteration of dairy products such as bovine milk [ 13 ]; to differentiate between oliva varieties [ 14 ], to monitor the ripening of fruit [ 15 ]; to discriminate between fresh and frozen-thawed fish [ 16 ]; and to identify changes in pork during refrigerated storage [ 17 ]. EIS has been also extensively applied for agricultural product quality detection [ 18 ].…”

Improving FPGA Based Impedance Spectroscopy Measurement Equipment by Means of HLS Described Neural Networks to Apply Edge AI

“…Therefore, FPGAs have been integrated into different research areas' instrumentation equipment [9]. Regarding Impedance Spectroscopy, FPGA-based systems can be found in different studies [10][11][12][13].…”

“…Several statistical methods such as principal component analysis, linear discriminant analysis, ANOVA, least-squares analysis, and several machine learning methods such as logistic regression, support vector machine, and K-nearest neighbors have been applied successfully to extract information from the measured data [16]. Also, there are some works that have successfully applied data analysis based on Artificial Intelligence (AI) techniques [13,17].…”