Spectrophotometric determination of the levels of ca, mg, k and na in pasteurized goat milk, consumed in the city of Maracaibo

Abstract

Goat milk is a beneficial alternative in human nutrition, based on its easy digestibility for consumers who are allergic to proteins and lactose intolerant of cow’s milk. That is why the consumption of goat’s milk is increasing day by day. In this paper, the concentrations of Ca, Mg, K, and Na are presented in samples of pasteurized goat milk sold in the city of Maracaibo, determined by 
the techniques of absorption and atomic emission with flame (FAAS and FAES). A random sampling was carried out, collecting samples of goat liquid milk (n = 35), in commercial presentations of 1L. The samples were digested with HNO 3 / H 2 O 2 using heating at atmospheric pressure,in order to eliminate the organic matter, mainly fat. The overall average precision (expressed as DER) was 0.99%. The accuracy of the method was evaluated through recovery studies, obtaining average percentages between 95 and 105%. The detection limits (L D = 3σ / m) obtained were 0.027; 0.005; 0.002 and 0.002 mg / L for Ca, Mg, K and Na, respectively. The concentrations obtained (mean ± SD, mg / L) were: Ca, 960.72 ± 64.32; Mg, 98.84 ± 0.12; K, 1416.51 ± 23.09; and Na, 1296.61 ± 41.44. These concentrations were below the levels expected for calcium, magnesium and potassium, unlike sodium, which was found at high levels detrimental to health, suggesting possible adulteration with NaCl. The methodologies applied were accurate, precise and free of interference.