Evaluation of Sample Preparation Methods for the Determination of Ca, Cu, Fe, K, and Na in Milk Powder Samples by ICP-OES

Determination of Ca, P, K, Na, and Mg in Australian Retail Pasteurised Milk Using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP OES)

A rapid and simple inductively coupled plasma atomic emission spectrometry (ICP OES) method was developed and validated for the determination of macroelements including calcium (Ca), phosphorus (P), potassium (K), sodium (Na), and magnesium (Mg) in Australian retail pasteurised milk. The milk samples were digested using the mixture of 70% HNO3 and 30% H2O2 (2 : 1, v/v) in an open-tube digester block at 120°C for 4 h. The validated ICP OES method showed good linearity for all elements (R 2 > 0.9993). The method limits of quantification (LOQ) for Ca, P, K, Na, and Mg were 19.85, 8.97, 100.8, 41.92, and 11.56 µg·g-1, respectively. Recoveries were in the range of 91.54-116.0%. Repeatability and interday reproducibility expressed as the relative standard deviation (% RSD) was below 5.0%. The contents of macroelements in 6 retail pasteurised milk samples were between 1099.32 and 1348.65 µg·g-1 (Ca), 914.01 and 1091.21 µg·g-1 (P), 1362.76 and 1549.74 µg·g-1 (K), 288.89 and 323.22 µg·g-1 (Na), and 97.62 and 110.57 µg·g-1 (Mg). Principal component analysis (PCA) revealed that retail pasteurised milk samples were distinctly separated into four groups on the first two principal components (PCs). The difference in the macroelement content between milk brands might be affected by milk regions.

Validating the preeminence of biochemical properties of camel over cow and goat milk during the Covid‐19

In the light of the Covid‐19 pandemic outbreak, and the need‐of‐the‐hour to boost immunity to residents, especially those residing in an arid environment, a comparative study was made on the physical and biochemical properties of dairy milk. This novel study in Kuwait revealed the lesser consumed pseudoruminant camel milk as a better potential source of dietary inclusion and an immune booster over true ruminants—cow's and goat's milk. Analysis using a wide array of instruments determining the physical characteristics in camel's milk (pH, conductivity, specific gravity, moisture, and total solids), biochemical constituents (crude protein (CP), nonprotein (NP), and fat), and inorganic constituents (K‐919; Ca‐907; Zn‐4.2 mg/100 mg) revealed conducive properties that validate immunity to consumers when compared to the regularly used cow's milk (K‐841; Ca‐776; Zn‐2.43 mg/100 mg) and goat's milk (K‐914; Ca‐849; Zn‐2.45 mg/100 mg). Log‐transformed results revealed high vitamin C in camel's milk (0.42 mg/100 g), indicating high antioxidant properties compared to those of goat's milk (0.12 mg/100 g) and cow's milk (0.04 mg/100 g). Statistical tests by analysis of variance (ANOVA) revealed significant differences and the correlation coefficient between the three milk samples validating the multiple reasons to use camel's milk over the cow's and goat's milk. Furthermore, this study recommends the consumption of camel's milk due to its low concentrations of contaminants as well, their status below permissible limits in Kuwait, set by global standards over the other sampled milks.

Determination of Trace Elements in Infant Formulas Available on Polish Market

The aim of this study was to assess the levels of 13 essential and toxic elements (As, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Se, V, Zn) in the infant formulas, available on Polish market. Selected food samples were of animal (cow- and goat-based milks) and plant (soy-based milk, hypoallergic products, grain porridges) origin. Two analytical techniques, inductively coupled plasma mass spectrometry (ICP-MS) and neutron activation analysis (NAA), have been complementarily applied to analyze elemental content of 16 formulas dedicated for infants between 0 and 8 months. For arsenic determinations, the radiochemical mode of NAA was also used. The daily intake of some micronutrients in the age 0-8 months for non-breastfed infants was estimated and compared with present safety limits. Certified reference materials (CRMs) have been used for the validation of the methods: Non-fat Milk Powder 1549 (National Bureau of Standards-NBS), Soya Bean Flour INCT-SBF-4 (Institute of Nuclear Chemistry and Technology-INCT), Rice Flour SRM 1568b (National Institute of Standards and Technology-NIST).