Electrical Impedance Sensor for Real-Time Detection of Bovine Milk Adulteration

This paper presents a developed methodology for the detection of bovine milk adulteration by applying electrical impedance measurements. This parameter allows characterizing samples of raw and ultrahigh temperature milk, adulterated with different proportions of drinking water, deionized water, hydrogen peroxide (H
₂
O
₂
), sodium hydroxide (NaOH), and formaldehyde (CH
₂
O). The samples were electrically analyzed by applying the electrical impedance spectroscopy measurements and a dedicated microcontroller system, developed for this application. In both cases, the measures allowed classifying the milk quantitatively, enabling the development of real-time monitoring systems for fraud detection in milk composition. A classification of the results is proposed through a k-nearest neighbors algorithm that allows to quantitatively qualify the samples of pure and adulterated milk.