Trace Elements In Milk Research Articles

Heavy metals and trace elements in milk and dairy products in the Lazio region (Central Italy)

ABSTRACT A study was carried out to determine the concentration of heavy metals and trace elements in milk and dairy products collected from local farms, supermarkets, or food retailers in the region of Lazio (Central Italy). Persistent exposure to metal contamination is of particular concern for human health, as it can cause different serious disorders. The monitoring of the matrices studied is therefore important, given their high consumption in the daily diet. The elements determined by ICP-MS (Inductively Coupled Plasma – Mass Spectrometry) were lead (Pb), arsenic (As), mercury (Hg), cadmium (Cd), chromium (Cr), nickel (Ni), molybdenum (Mo) and thallium (Tl), for a total of 151 measurements in 98 samples. The results showed that 11.3% of the measurements were quantifiable but below the legal maximum limits (MLs) set by EU regulations. The data obtained may be useful for dietary exposure information, inter-regional comparisons and for planning regional surveillance strategies.

Macro Minerals and Trace Elements in Milk of Dairy Buffaloes and Cows Reared in Mediterranean Areas

Aim of this study was to evaluate the differences in Ca, P, K, Na, Mg, Zn, Fe, Cu, Mn, Se, Mo, Co, Li, B, Ti, Rb, and Sr concentrations in milk from buffaloes and cows reared in the same farm in Mediterranean areas and fed diets including the same ingredients. Individual milk samples were obtained from 32 Mediterranean buffaloes and 29 Italian Friesian cows and samples of milk, dietary ingredients and drinking water were analyzed for the investigated chemical elements by inductively coupled plasma-mass spectrometry. Data about milk element concentrations were processed by one-way analysis of variance. Buffalo milk contains higher concentrations of Ca, P, Mg, Zn, Fe, Cu, B, Ti, and Sr, and lower concentrations of K, Na, Mo, Li, and Rb compared to cow milk, whereas milk from both species contains similar concentrations of Mn, Se, and Co. The concentrations of the investigated elements in the diet were similar for both species and the differences observed between buffalo and cow milk were not dependent on environmental factors.

Compare the nutritional status of essential minerals in milk of different cattle and humans: Estimated daily intake for children

In present study, the comparisons of electrolytes, calcium (Ca), potassium (K), magnesium (Mg), sodium (Na) phosphorus (P), and essential trace elements, iron (Fe), zinc (Zn), copper (Cu) and selenium (Se) were carried out in milk samples of different cattle (cow, buffalo, goat, sheep, and camel) and human as total and soluble form (whey of milk). The sampling of milk was carried out from different farms, flocks and human from rural areas of Hyderabad city. The electrolytes and essential trace elements in milk, as total and soluble (whey) forms were determined by different techniques, after acid digestion method. The concentrations of Na, K Ca, P and Mg were significantly higher in camel milk, whereas, the contents of K were elevated in goat and sheep milk. As compared to the different cattle, human milk had the lowest concentrations of all selected essential trace elements except Se. The percentages of all elements in whey milk were found in the range of 20 to ≥ 95 % of their total contents in whole milk samples of different cattle and human. The estimated daily intake of all elements was calculated for infants <0.6 month to 10 years old children via consuming milk of cattle and humans. It is notable that milk of each species has a specific individual pattern of electrolytes and essential trace elements, which might be an indicator of relative nutritional importance for human of all age groups.

Contamination and Health Risks of Certain Heavy Metals and Trace Elements in Milk and Milk Products Consumed in Province of Monufia, Egypt.

The objective of this study was to determine the residue levels of some heavy metals and heavy elements a total of 52 different random milk and cheese samples (16 samples of milk 4 raw and 12 of dairy milk purchased from local supermarkets in their original covers from 3 different company and (36 cheese samples (vita, olive and astamboly) purchased from local supermarkets from three different company in their original package collected from 9 towns inside the province of Monufia, Egypt. All examined samples were analyzed by Atomic Absorption Spectrophotometer to determine heavy metal residues and trace elements [lead (Pb), Cadmium (Cd), Copper (Cu), zinc (Zn), N|ikal (Ni) and manganese (Mn)]. and estimated the daily intake and health risk index. The highest trace metals accumulation levels for Cd are found in milk samples collected from factory A and B while not detected in factory C, while samples from factory A, B and C had high levels in Pb and Mn. The most abundant element in all tested cheeses was Zn, the richest content of Zn was identified in the three tested cheeses, the metal Zn in Olive cheese was 5.415, 3.718 and 4.16 mg/kg for factory A.B and C, respectively. The metal Cd not detected in all cheese tested. The THQ of all metals (Cd, Pb, Cu, Cr, Ni, Mn and Zn) via milk and dairy products consumption were less than one. The large variance and some high levels of contamination could be attributed to the application of quality standards in manufacturing and comparison with the other manufacturer.

Comprehensive Assessment of Essential and Potentially Toxic Trace Elements in Bovine Milk and Their Feeds in Different Agro-climatic Zones of Sri Lanka.

Fresh milk is an important source of essential mineral supplement for humans. However, the levels of trace elements in milk are an important component of its safety and quality. Trace elements also act as a bio-indicator of agricultural pollution. Samples of raw cow milk (n= 68), animal feed [forage (n= 36) and concentrates (n= 14)], and water (n= 35) were collected from different agro-climatic regions of Sri Lanka. The concentrations of 15 trace elements including toxic heavy metals such as Cd, Pb, and As were quantified using inductively coupled plasma mass spectrometry after microwave-assisted digestion. Among the studied trace elements, the mean elemental concentrations of Se, Cd, As, and Cu in cow milk were 18.1, 1.45, 7.35, and 71.7μgL-1, respectively. The mean concentrations of these elements in forage were 0.216, 0.066, 0.046, and 9.21mgkg-1, and in concentrate feed were 0.329, 0.202, 0.229, and 2.28mgkg-1, respectively. The As content of the studied milk was well below the maximum permissible level while 15% of the samples had Pb exceeding the permissible limit of 20μgL-1. However, As, Cd, and Pb levels in drinking water provided to animals were well below the WHO permissible limits. The results of this study revealed that the trace elements in cow milk depend mainly on the feed, and hence, levels of these contaminants in feed materials should be monitored. Although due to the consumption of milk, the populations have a minor exposure to trace elements and also minimum health risks, a detailed study with a large number of samples is highly recommended.

Determination of Minerals and Trace Elements in Milk, Milk Products, Infant Formula, and Adult Nutrition: Collaborative Study 2011.14 Method Modification

Abstract Official Method SM 2011.14/ISO 15151:2018/IDF 229:2018 uses microwave digestion of samples and inductively coupled plasma–atomic emission spectrometry for determination of nine elements, including Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn. The method was evaluated in a collaborative study of 25 products, including 13 fortified nutritional products (powders, ready-to-feed liquids, and liquid concentrates), five product placebos, six dairy products (liquids, powders, butter, and processed cheese), and the National Institute for Standards and Technology (NIST) Standard Reference Material (SRM) 1849a, in compliance with AOAC INTERNATIONAL Standard Method Performance Requirement (SMPR®) 2014.004. This study significantly expanded the applicability of Official Method 2011.14 beyond the original scope of chocolate milk powder, dietetic milk powder, infant cereal, peanut butter, and wheat gluten. The study included 14 collaborators from 11 countries, and results were compared to SMPR 2014.004. Accuracy of the method was demonstrated using NIST SRM 1849a, yielding recoveries across all laboratories of 98–101% for the nine elements. Precision for the 13 fortified nutritional product samples was 2.2–3.9% for repeatability (relative SD of repeatability) and 6.0–12.2% for reproducibility (RSDR). Excluding Mn, which was present at a wide range of concentrations, the reproducibility was 6.0–9.5%, meeting the performance requirements of SMPR 2014.004. Placebo samples (not fortified with Cu, Fe, Mn, or Zn) yielded acceptable repeatability of 1.8–2.9% for Ca, K, Mg, Na, and P (minerals) but 5.4–29.4% for the low levels of Cu, Fe, Mn, and Zn (trace elements). Reproducibility for the placebos showed the same pattern, with acceptable reproducibility (5.4–10.3%) for minerals but not for the low levels of the trace elements (13.2–82.8%). In the six dairy product samples, repeatability ranged from 1.6 to 3.6% for the minerals, Zn, and the low range of Mn but from 9.4 to 24.6% for Cu, Fe, and the high range of Mn, where concentrations were low as for the nutritional placebos. Reproducibility in the dairy samples was 5.3–8.8% for the minerals but 11.4–55.0% for the trace elements. The mean concentrations of Cu, Fe, and Zn in the dairy products were similar with those in the placebo products, while Zn was present at levels more similar with the fortified nutritional products. Thus, the method met the SMPR criteria except where the trace minerals were present at very low levels. Based on these results, the AOAC Stakeholder Panel for Infant Formula and Adult Nutritionals recommended Final Action status of the expanded applicability of the method. The method was adopted as Final Action by the AOAC Official Methods Board.

О НЕКОТОРЫХ ЗАКОНОМЕРНОСТЯХ ИЗМЕНЕНИЯ ФИЗИКО-ХИМИЧЕСКОГО СОСТАВА СЕКРЕТА МОЛОЧНОЙ ЖЕЛЕЗЫ КОРОВ

Studies have shown the effect on the physical and chemical parameters of beestings and milk of metabolic correctors used by animals in accordance with the scheme developed by the authors. The experiment was carried out on 30 cows of the Holstein breed contained in the agricultural factory “Plemzavod im. Lenin” of Atninsky district of the Republic of Tatarstan. The content of the mass fraction of fat, the mass fraction of protein in beestings and milk was determined on “Laktan 1-4” milk quality analyzer, the content of trace elements in milk was determined on “Analist 200” atomic absorption spectrophotometer according to the manufacturer’s method. The use of vitamin-mineral premix P60-3/P in the final 15 days of the dry period in combination with metabolic correctors is accompanied by a maximum content of protein mass fraction in beestings (6.0%), and an increase in the use of this premix to the entire duration of the dry period allows increasing the mass the proportion of fat in beestings is up to 5.41%, however, these changes were not reliable. A significant decrease in the mass fraction of protein in the milk of cows of the control group (P &lt;0.05) and a significant increase in the mass fraction of fat in animals of the third group to 4.13% (P &lt;0.05) on the 30th day of lactation were found. On day 30 of lactation, a significant increase in the content of copper and selenium in the milk of individuals of the second (66.2% (P &lt;0.01) and 65.2% (P &lt;0.05), respectively) and the third (67.2% (respectively P &lt;0.001) and 73.0% (P &lt;0.01)) groups. On the 60th day of lactation in animals of the first group, the increase in the zinc content in milk was reliable and amounted to 6.9% (P &lt;0.05). In cows of the second and third groups, the copper content was significantly higher than in animals of the first group by 60.3% (P &lt;0.01) and 62.6% (P &lt;0.01), respectively. In individuals of the third group, the selenium content was significantly higher than in animals of the first (control) group by 94.2% (P &lt;0.01). This article was prepared as part of the state task AAAA-A18-118031390148-1.

Determination of Minerals and Trace Elements in Milk, Milk Products, Infant Formula, and Adult Nutrition: Collaborative Study 2011.14 Method Modification

Official MethodSM 2011.14/ISO 15151:2018/IDF 229:2018 uses microwave digestion of samples and inductively coupled plasma-atomic emission spectrometry for determination of nine elements, including Ca, Cu, Fe, K, Mg, Mn, Na, P, and Zn. The method was evaluated in a collaborative study of 25 products, including 13 fortified nutritional products (powders, ready-to-feed liquids, and liquid concentrates), five product placebos, six dairy products (liquids, powders, butter, and processed cheese), and the National Institute for Standards and Technology (NIST) Standard Reference Material (SRM) 1849a, in compliance with AOAC INTERNATIONAL Standard Method Performance Requirement (SMPR®) 2014.004. This study significantly expanded the applicability of Official Method 2011.14 beyond the original scope of chocolate milk powder, dietetic milk powder, infant cereal, peanut butter, and wheat gluten. The study included 14 collaborators from 11 countries, and results were compared to SMPR 2014.004. Accuracy of the method was demonstrated using NIST SRM 1849a, yielding recoveries across all laboratories of 98-101% for the nine elements. Precision for the 13 fortified nutritional product samples was 2.2-3.9% for repeatability (relative SD of repeatability) and 6.0-12.2% for reproducibility (RSDR). Excluding Mn, which was present at a wide range of concentrations, the reproducibility was 6.0-9.5%, meeting the performance requirements of SMPR 2014.004. Placebo samples (not fortified with Cu, Fe, Mn, or Zn) yielded acceptable repeatability of 1.8-2.9% for Ca, K, Mg, Na, and P (minerals) but 5.4-29.4% for the low levels of Cu, Fe, Mn, and Zn (trace elements). Reproducibility for the placebos showed the same pattern, with acceptable reproducibility (5.4-10.3%) for minerals but not for the low levels of the trace elements (13.2-82.8%). In the six dairy product samples, repeatability ranged from 1.6 to 3.6% for the minerals, Zn, and the low range of Mn but from 9.4 to 24.6% for Cu, Fe, and the high range of Mn, where concentrations were low as for the nutritional placebos. Reproducibility in the dairy samples was 5.3-8.8% for the minerals but 11.4-55.0% for the trace elements. The mean concentrations of Cu, Fe, and Zn in the dairy products were similar with those in the placebo products, while Zn was present at levels more similar with the fortified nutritional products. Thus, the method met the SMPR criteria except where the trace minerals were present at very low levels. Based on these results, the AOAC Stakeholder Panel for Infant Formula and Adult Nutritionals recommended Final Action status of the expanded applicability of the method. The method was adopted as Final Action by the AOAC Official Methods Board.

Analysis of milk trace elements with a home-made portable automated total reflection x-ray fluorescence system

This paper presents a portable, high-tech, low-cost, total reflection X-ray fluorescence system. This system features a compact arrangement consisting of a 50 W X-ray mini-tube with a Mo anode and a Si-PIN detector, quartz reflectors, lucite monochromator and micrometric tables driven by step motors controlled through the Arduino programming software. A certified sample of bovine liver SRM 1577b by NIST was used for the validation of the portable automated TXRF system. The TXRF system was used in the analysis of bovine milk samples collected in the industrialized region of the city of Bauru, São Paulo. In the analysis of the bovine milk samples the following elements were detected: P, S, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Se, Rb and Sr. The TXRF portable automated system proved to be efficient, showing that it is possible to produce X-ray fluorescence with a low-cost system using a low-power X-ray tube and a compact Si-PIN detector.

Study of effect of maternal nutrition on breast milk trace elements in malnourished versus well-nourished mothers

Background: Minerals and trace element content of human milk have been a matter of concern among nutritionist in relation to the availability of the essential elements to the new born. Mineral and trace elements occur in the body in a number of chemical forms, such as inorganic ions and salts, or as constituents of organic molecules, for example proteins, fats, carbohydrates and nucleic acids. There is a paucity of data on the effect of nutrition on the composition of trace elements in milk and its effect on the infant. Hence a comparison made between the trace element and mineral such as sodium, potassium, magnesium, iron, zinc, copper, calcium in milk of malnourished and well-nourished mothers in order to determine the effect of maternal nutrition on the quality of milk and its effect on the growth and physical development of the new-born.Methods: Around 100 mothers were enrolled in the study after obtaining prior informed consent. They were divided into 2 groups-group I had 50 malnourished mothers and group II had 50 well-nourished mothers. The pre-fed milk sample which was collected was stored at - 20℃ until it was processed. It was thawed and analysed for copper, zinc, iron, magnesium, sodium, potassium and calcium.Results: The mean levels of trace elements (iron and zinc) and minerals (sodium, potassium, calcium, magnesium) were slightly more among well-nourished than malnourished women. Values of only copper were significantly higher in the colostrum of well-nourished as compared to that of the malnourished mothers.Conclusions: The parameters of weight, height weight/height ratio and hemoglobin varied significantly between the well-nourished and malnourished mothers. The difference in milk content of malnourished and well-nourished mothers is not significant for sodium, potassium, calcium, iron, magnesium, zinc. However, copper levels were significantly higher in well-nourished mothers.

Risk Assessment of Certain Heavy Metals and Trace Elements in Milk and Milk Products Consumed in Aswan Province.

Considering that pollutants transformed to human body through food consumption, food safety is of great concern to consumers. Because consumption of milk contaminated with heavy metals poses serious threats to consumer's health. This study was conducted to evaluate the concentration of heavy metals and its risk with the consumption of milk and milk products in Aswan Province . A total of 20 samples of raw fresh buffalo, cow, sheep and goat milk and 16 samples of milk products of Kareish cheese, Domiati cheese, Mish and Samna were analyzed for the presence of heavy metals of Cadmium (Cd) and Lead (Pb) and trace elements of Copper (Cu) and Zinc (Zn) via Atomic Adsorption Spectrophotometer (AAS). The results showed that the concentration of total heavy metals differed between different areas, it was the highest in Edfu but the least in Toshka. With the analysis of metals concentration in milk of different species, the results showed higher concentration of total metals in sheep and goat milk combined with low content of Cd and high content of Zn and Cu than that of cow and buffalo milk. Comparing the Cd, Pb, Cu and Zn concentrations in locally manufactured milk products with the permissible upper limit of EOS (1993), the results are within the permissible limit. The health risk assessment of metals was assessed on the basis of determining of EDI and THQ for inhabitants through the consumption of contaminated milk and milk products. The EDI of Cd and Pb contributed to 59.7% and 20.48% of PTDI, while Zn contributed to 0.0345 to 2.582% and 0.0475 to 3.55% of RDA for male and female, respectively, but the Cu contributed to 0.0555 to 7.466 % of RDA. The results also showed that THQ of all metals under studies are less than one via the consumption of milk and milk products which means that inhabitants in Aswan Governorate will not exposed to health risk from the consumption of raw milk and milk product.

Minerals and Trace Elements in Milk, Milk Products, Infant Formula, and Adult/Pediatric Nutritional Formula, ICP-MS Method: Collaborative Study, AOAC Final Action 2015.06, ISO/DIS 21424, IDF 243.

AOAC Final Action Official MethodSM 2015.06 "Minerals and Trace Elements in Milk, Milk Products, Infant Formula and Adult/Pediatric Nutritional Formula, ICP-MS Method" was collaboratively studied. Note that "milk, milk products" has now been added to the title of the Final Action method because whole milk and several dairy ingredients were successfully incorporated into the collaborative study for the purpose of developing an International Organization for Standardization/International Dairy Federation standard (ISO/DIS 21424; in progress). The method determines sodium, magnesium, phosphorus, potassium, calcium, iron, manganese, zinc, copper, chromium, molybdenum, and selenium by inductively coupled plasma (ICP)-MS after microwave digestion. Ten laboratories participated in the study, and data from five different model ICP-MS units were represented. Thirteen products, five placebo products, and six dairy samples were tested as blind duplicates in this study, along with a standard reference material, for a total 50 samples. The overall repeatability and reproducibility for all samples met Standard Method Performance Requirements put forth by the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals, with a few exceptions. Comparisons are made to ICP-atomic emission data from a collaborative study of AOAC Official Method 2011.14 carried out concurrently on these same samples.

Concentrations of macroelements and trace elements in milk of Jersey cows

The aim of the study was to determine concentration of macroelements (P, Ca, Mg, Na, K), and some microelements, including toxic heavy metals (Cr, Fe, Mn, Zn, Cu, Co, Pb, Cd and Hg) in milk of Jersey cows. Milk samples were collected from Jersey cows kept in tie-stall barn in Greater Poland Province. The feeding was based on total mixed ration mixture. The maximum permitted level of Pb concentration in raw milk (0.02 mg/kg wet weight)was significantly exceeded (0.063±0.035 mg/dm3). The content of Hg was very low (0.106±0.057 μg/dm3).Significant (P£0.05) Spearman coefficient correlations were observed between contents of some elements in milk. Especially interesting were positive correlations of heavy metals: Cd-Cr, Co-Mn, Cr-Zn, Mn-Zn. Additionally the content of Ca was positively correlated with numerous elements: Hg, Cr, Cu, Mn, Zn, Mg, and negatively correlated with the content of Fe.

The levels and correlation analysis of trace elements in maternal blood, breast milk and infant blood

Objective To investigate the correlation of trace elements in maternal blood, breast milk and infant blood. Methods A tomic absorption spectrographic method was used to measure blood and milk trace elements [calcium (Ca), ferrum (Fe), zinc (Zn), magnesium (Mg), copper(Cu)] of maternal of natural delivery and infant in 250 cases, then to analyze the correlation of trace elements in maternal blood, breast milk and infant blood in postpartum 42 days. Results There were statistically significant differences in trace elements between the maternal blood, breast milk and infant blood (P<0.05). There was a positive correlation of Ca, and Fe between maternal blood and infant blood [Ca (r=0.221, P=0.047), Fe (r=0.107, P=0.043)]; Fe had a positive correlation between breast milk and infant blood (r=0.139 P=0.035); There was a positive correlation of the trace elements between maternal blood and milk, but no correlation in Mg. Conclusions There was the gradient of trace elements in maternal blood and breast milk in postpartum 42 days. It can keep breast milk in a certain percentage of trace element and contribute to absorption of trace elements and growth and development in infant. The regular determination of trace elements during pregnancy and postpartum in women and their infant can direct a balanced diet and advocate breastfeeding. It can also prevent the lack of calcium, iron, zinc and other trace elements in infant. Key words: Trace elements/ME; Infant; Parturition/ME

Minor and potentially toxic trace elements in milk and blood serum of dairy donkeys

The aim of this trial was to study the concentration of Ti, V, As, Rb, Sr, Mo, Cd, Cs, and Pb in donkey milk and blood serum. One hundred twelve individual milk and blood serum samples were collected from 16 lactating donkeys (Martina-Franca-derived population; 6 to 12 yr old; 3 to 7 parities; average live weight 205.4kg; 32 to 58 d after foaling at the beginning of the trial) during a 3-mo-long experiment. The samples were analyzed for the aforementioned elements by inductively coupled plasma-mass spectrometry. Feedstuff and drinking water were also analyzed for the investigated elements. Data were processed by ANOVA for repeated measures. Average milk concentrations (±SD) of Ti, Rb, Sr, Mo, Cs, and Pb were 77.3 (±7.7), 339.1 (±82.1), 881.7 (±270.4), 4.5 (±1.6), 0.49 (±0.09), and 3.2 (±2.7) μg/L, respectively. More than 80% of samples were below the limit of detection for V, As, and Cd in milk and for Cd, and Pb in blood serum. The lower bound calculated for milk V, As, and Cd was 0.03μg/L for the 3 elements, the upper bound was calculated at 0.23, 0.10, and 0.31μg/L and the maximum value was observed at 0.54, 0.15, and 0.51μg/L, respectively. The average milk concentrations of Ti, Rb, Sr, Mo, and Cs were 600, 458, 346, 16, and 294%, respectively, than those of blood serum. Yet, Cs concentrations were in the same order of magnitude in milk and serum. Moderate to strong positive and significant correlation coefficients were observed between milk and blood serum concentrations for Ti, Rb, Sr, and Cs. The effect of the stage of lactation was significant for all the investigated elements in milk and blood serum, but most of the elements showed only small changes or inconsistent trends, and only the concentrations of Rb and Sr showed decreasing trends both in milk and blood serum. The relationship between milk and blood serum element concentrations indicates that the mammary gland plays a role in determining the milk concentrations of Mo, Ti, Rb, Sr, Mo, and Cs. In the current experimental conditions, in agreement with the low levels in drinking water and feedstuff, donkey milk concentration of potentially toxic elements was very low and did not raise health concerns for human consumption.

Trace elements in bovine milk from different regions in Norway

Dairy milk samples from 37 milk tours in 15 areas of Norway were collected during indoor feeding or on pasture in 2008 and analyzed with respect to 6 major elements (Ca, P, K, S, Na, Mg) and 28 trace elements (As, Ba, Be, Bi, Cd, Ce, Co, Cr, Cs, Cu, Dy, Fe, I, La, Li, Mn, Mo, Nd, Pb, Rb, Sb, Se, Sm, Sr, V, Y, Yb and Zn). Surprisingly, the least-square means of major and trace elements in milk did not vary much from one region to another. The concentration levels of iodine, copper, manganese and lithium in milk from the northern region were higher compared with milk from other regions. Milk from the south was enriched with respect to selenium, yttrium, cerium and bismuth, while milk from the western region was enriched with respect to rubidium.

Major and trace elements in milk and Halloumi cheese as markers for authentication of goat feeding regimes and geographical origin

Sixty samples of milk, Halloumi cheese and local grazing plants (i.e. shrubs) were collected over a year from dairy farms located on three different locations of Cyprus. Major and trace elements were quantified using inductively coupled plasma–atomic emission spectroscopy (ICP‐AES). Milk and Halloumi cheese produced in different geographical locations presented significant differences in the concentration of some of the elements analysed. Principal component analysis showed grouping of samples according to the region of production for both milk and cheese samples. These findings show that the assay of elements can provide useful fingerprints for the characterisation of dairy products.

Analysis of minor and trace elements in milk and yogurts by inductively coupled plasma-mass spectrometry (ICP-MS)

This study aimed at analysing the content of 22 minor and trace elements in milk and yogurts from South Korea, using inductively coupled plasma-mass spectrometry (ICP-MS), after digestion using heating block. The analytical method was validated by detection limits, precision, accuracy and recovery experiments, obtaining satisfactory results in all cases. Results of both minor and trace elements were found mostly similar in all varieties of milk and yogurts studied. Copper and manganese were comparatively high in fruit mixed yogurts, while selenium was high in milk samples. The overall concentrations of minor elements were found to have good nutritional values in accordance to RDA. Zn showed the highest concentration, followed by Rb, Se, Sr and Cr. The level of toxic trace elements, including As, Cd and Pb were very low and did not pose any threat to consumers.

Essential trace elements in milk and blood serum of lactating donkeys as affected by lactation stage and dietary supplementation with trace elements

The aim of this trial was to study the concentration of zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), selenium (Se), cobalt (Co) and iodine (I) in milk and blood serum of lactating donkeys, taking into account the effects of lactation stage and dietary supplementation with trace elements. During a 3-month period, 16 clinically healthy lactating donkeys (Martina-Franca-derived population), randomly divided into two homogeneous groups (control (CTL) and trace elements (TE)), were used to provide milk and blood samples at 2-week intervals. Donkeys in both groups had continuous access to meadow hay and were fed 2.5 kg of mixed feed daily, divided into two meals. The mixed feed for the TE group had the same ingredients as the CTL, but was supplemented with a commercial premix providing 163 mg Zn, 185 mg Fe, 36 mg Cu, 216 mg Mn, 0.67 mg Se, 2.78 mg Co and 3.20 mg I/kg mixed feed. The concentrations of Zn, Fe, Cu, Mn, Se, Co and I were measured in feeds, milk and blood serum by inductively coupled plasma-MS. Data were processed by ANOVA for repeated measures. The milk concentrations of all the investigated elements were not significantly affected by the dietary supplementation with TE. Serum concentrations of Zn, Fe, Cu Mn and Se were not affected by dietary treatment, but TE-supplemented donkeys showed significantly higher concentrations of serum Co (1.34 v. 0.69 μg/l) and I (24.42 v. 21.43 μg/l) than unsupplemented donkeys. The effect of lactation stage was significant for all the investigated elements in milk and blood serum, except for serum manganese. A clear negative trend during lactation was observed for milk Cu and Se concentrations (−38%), whereas that of Mn tended to increase. The serum Cu concentration was generally constant and that of Co tended to increase. If compared with data reported in the literature for human milk, donkey milk showed similarities for Zn, Mn, Co and I. Furthermore, this study indicated that, in the current experimental conditions, the mineral profile of donkey milk was not dependent on dietary TE supply.

Content of selected essential and potentially toxic trace elements in milk of cows maintained in Eastern Poland

Concentration of toxic metals in milk, especially in industrial regions, may serve as a direct bioindicator of the quality of milk and its products. But it can also function as an indirect indicator of contamination of the environment where milk is produced. The aim of the present study was to evaluate the content of some trace elements, i.e. Fe, Cu, Zn and Mn, as well as toxic elements (Cd and Pb) in milk from cows maintained on farms in three regions of Poland, including the production season as another aspect of the investigations. In total, 446 milk samples were analyzed. Significant influence of the season and production region on all the analyzed elements except Fe was noticed. Milk collected in the Biebrza and Bieszczady regions proved to be a richer source of Cu and Mn. Regardless of the production region, a higher content of Zn and Cu were observed in the summer, while more Mn was found in the winter milk. In none of the analyzed milk samples, Pb or Cd exceeded the permissible threshold.