Quantification of Urea Adulteration with Impedance Spectroscopy in Cow Milk

Abstract

Cow milk plays an important role in nutrition of human being, especially in infant stage. An attempt is carried out to quantify urea adulteration in cow milk with help of impedance spectroscopy. Designed sensor and signal conditioning circuit converts impedance of milk to voltage. This changes in impedance in turn changes in phase angle of the output signal of sensor, enables identifying milk adulterated with different percentage of urea. After confirming frequency used for detection, the effect of level of adulteration on resistance, impedance and phase angle are investigated with developed method. Experimentation endows detection and quantification of urea in Cow milk with measurement of impedance as well as phase angle of output signal. Though simple design of sensors and signal conditioning circuit, the system allows urea detection up to 70mg in 100ml of milk. The estimation of adulteration in milk with developed system is possible within 45 seconds. This time required to settle down the temperature of the milk due to addition of urea. The effect of temperature after addition of urea can further be studied.