Voltamperometric Discrimination of Urea and Melamine Adulterated Skimmed Milk Powder

ASTRID HILDING-OHLSSON; JONATHAN A. FAUERBACH; NATALIA J. SACCO; M. CELINA BONETTO; EDUARDO CORTÓN

SENSORS

MOLECULAR DIVERSITY PRESERVATION INTERNATIONAL-MDPI

Lugar: Basel; Año: 2012 vol. 12 p. 12220 - 12234

1424-8220

Nitrogen compounds like urea and melamine are known to be commonly used for milk adulteration resulting in undesired intoxication; a well-known example is theChinese episode occurred in 2008. The development of a rapid, reliable and economic test is of relevance in order to improve adulterated milk identification. Cyclic voltammetrystudies using an Au working electrode were performed on adulterated and non-adulterated milk samples from different independent manufacturers. Voltammetric data and their firstderivative were subjected to functional principal component analysis (f-PCA) and correctly classified by the KNN classifier. The adulterated and non-adulterated milk samples showedsignificant differences. Best results of prediction were obtained with first derivative data. Detection limits in milk samples adulterated with 1% of its total nitrogen derived frommelamine or urea were as low as 85.0 mg/L and 121.4 mg/L, respectively. We present this method as a fast and robust screening method for milk adulteration analysis andprevention of food intoxication.