Mineral Composition, Nitrogen Distribution of Goat’s Milk Produced under Algerian Steppe Condition across Lactation Stage

Goat milk constitutes a well-priced source of minerals and proteins for a large rural population, particularly those living in the mountains and whose access to state-subsidized milk is very limited. This study aims at assessing the mineral composition and nitrogen distribution of goat milk produced by the Algerian Arabia breed and estimating how lactation stage affects these elements. Thirteen individual Arabia goat milks were collected and analyzed three times during the lactation period (early, mid, and late). Minerals were analyzed by atomic absorption spectrometry and nitrogen fractions using the Kjeldahl method. The findings of the research showed that casein, whey, and milk protein content had respective mean values of 2.95, 0.74, and 3.54 g 100 ml⁻¹, respectively. The highest levels of minerals were found for calcium (537 μg ml⁻¹), and sodium (336 μg ml⁻¹). The average trace mineral concentration was between 1.78 μg ml⁻¹ (Fe) and 0.007 μg ml⁻¹ (Cs). Heavy metal concentrations were assessed to be 0.057 μg ml⁻¹ for Pb and 0.009 μg ml⁻¹ for Cd. An important effect of stage of lactation (p < 0.05) was observed on only K, Fe, and Na mineral components, whereas nitrogen distribution was not affected. As the lactation period progressed, the variation of these components was not constant and fluctuated across lactation stages.