Content of Mineral Elements in the Traditional Oštiepok Cheese

Levels of Essential and Trace Elements in Mozzarella Available on the Slovak Market with the Estimation of Consumer Exposure

The aim of this study was to determinate the content of some elements in a specific dairy product, mozzarella, in a particular area of western Slovakia and to evaluate the estimation of the risk to the consumers based on the contribution to the provisional tolerable weekly intake. The consumption of mozzarella can contribute to the intake of important elements in the diet, such as calcium and magnesium, along with others. The contents of some toxic and trace elements were low and have not exceeded the permitted limit. In addition, the contribution to PTWI was found to be very low, which means that the consumption of mozzarella possesses no risk to humans. It is concluded that the data obtained in this study can help as a valuable addition to methodological and scientific material in the field of food safety of dairy products and their positive impact on human health.

The use of olive cake in the diet of dairy cows improves the mineral elements of Provola cheese

Mineral elements (Ca, Na, K, Mg, Zn, Ti, Sr, Fe, Ni, Ba, Cr, Mn, Cu, Se, Cd, Mo, B, V, As, Pb and Hg) in Provola cheeses obtained from dairy cows fed with two different integrated diets (Biotrak) and without olive cake (Control) were determined to discriminate between the two different cheeses. The results showed that cheeses from the Biotrak group presented higher values of essential elements. Selenium (Se) was found to be the most interesting: in Biotrak cheeses the content of Se was in the range of 0.112 to 0.281 mg/kg, about twice the content of Se in cheeses from the Control group. Among the toxic elements, only Cd was found in the samples, but at low levels (in average lower than 0.11 mg/kg). Therefore, the use of olive cake in animal feed is a good strategy to improve the mineral profile of the product obtained.

Determination of Minerals in Soft and Hard Cheese Varieties by ICP-OES: A Comparison of Digestion Methods

For sample preparation prior to mineral analysis, microwave digestion (~2 h) is quicker and requires lower acid volume as compared to dry (6-8 h) and wet digestion (4-5 h). However, microwave digestion had not yet been compared systematically with dry and wet digestion for different cheese matrices. In this work, the three digestion methods were compared for measuring major (Ca, K, Mg, Na and P) and trace minerals (Cu, Fe, Mn and Zn) in cheese samples using inductively coupled plasma optical emission spectrometry (ICP-OES). The study involved nine different cheese samples with moisture content varying from 32 to 81% and a standard reference material (skim milk powder). For the standard reference material, the relative standard deviation was lowest for microwave digestion (0.2-3.7%) followed by dry (0.2-6.7%) and wet digestion (0.4-7.6%). Overall, for major minerals in cheese, strong correlation was observed between the microwave and the dry and wet digestion methods (R² = 0.971-0.999), and Bland-Altman plots showed best method agreement (lowest bias), indicating the comparability of all three digestion methods. A lower correlation coefficient, higher limits of agreement and higher bias of minor minerals indicate possibilities of measurement error.

Investigation of water-soil-plant relationships based on hazardous and macro-micro element concentrations on Orontes River, Türkiye

Arundo donax and Phragmites australis were examined in 4 different periods (June and October for 2 years), heavy metal and mineral element accumulations in plants were evaluated, and water-soil-plant relationships were revealed. Element distributions, bioaccumulation factors (BAF) and translocation factors (TF) in different parts of the investigated plant species were also determined. BAFs of elements calculated by using the concentration values in underground parts and sediment samples were between 1.02 and 4.96. While the highest TF was determined as 8.07 for Zn between washed leaf and stem in A. donax, the lowest TF was determined as 0.05 for Fe between stem and underground part. Corresponding highest and lowest TFs for P. australis were 11.80 for Cu between washed leaf and stem, and 0.02 for Fe between stem and underground part, respectively. The results were supported by MANOVA statistical analyzes. Additionally, the macro-micro elements and heavy metal accumulation levels in the parts of the Orontes River ecosystem were significantly higher in the fall periods compared to the spring periods. Our research revealed that the versatile accumulation properties and high accumulation ability of A. donax for Cd, Cr, and Ni and of P. australis for Cd, Co, Cu, Ni, Pb, and Zn.

Concentrations of Essential Trace and Toxic Elements Associated with Production and Manufacturing Processes in Galician Cheese

The objective of this study was to determine the trace element composition and the toxic metal residues in Galician cow’s milk cheese produced in different systems (artisan, industrial, and organic). Fourteen elements (As, Cd, Co, Cr, Cu, Fe, Hg, I, Mn, Mo, Ni, Pb, Se, and Zn) were determined in 58 representative samples of Galician cheeses by inductively coupled plasma mass spectrometry. The toxic elements were present at low concentrations, similar to those reported for other unpolluted geographical areas. The essential elements were also within the normal range in cheeses. There were no statistically significant differences between smoked and unsmoked cheeses for any of the elements. Chemometric analyses (principal component analysis and cluster analysis) revealed that the industrial cheeses produced in Galicia using the milk from intensive dairy farms were different, in terms of elemental content, from artisan and organic cheeses, in which the elemental contents were similar.

Aroma profile and lactic acid bacteria characteristic of traditional Slovak cheese "May bryndza"

This paper describes the results of the characterization of a traditional Slovak cheese called "May bryndza" with regard to the profiles of volatile organic compounds and lactic acid bacteria. Samples of "May bryndza" cheese produced solely from unpasteurized ewe's milk were collected from 4 different Slovak farms, and samples of the cheese produced from a mixture of 2 types of milk (raw ewe's and pasteurized cow's milk) were collected from 3 different Slovak industrial dairies. There were 15 compounds detected and identified by the electronic nose. The impact of the kind of milk and the kind of dairy on the aroma profile of the product was not confirmed by PCA. The compounds with the highest relative contents in samples were acetoin (2.59%-24.55%), acetic acid (6.69%-13.39%), methoxy-phenyl-oxime (4.49%-8.52%), butanoic acid (1.89%-5.67%), and 2,3-butanediol (0.98%-4.08%), which were determined with gas chromatography. A total of 1533 isolates of LAB were obtained from the "May bryndza" cheese samples. Four families, five genera, and 19 species were identified with mass spectrometry, and isolated bacteria, both from the farm and industry dairies were the most frequently found to belong to Lactococcus lactis subsp. lactis.

Diversity of microbiota in Slovak summer ewes' cheese "Bryndza"

"Bryndza" cheese is an important Slovak traditional regional product. New knowledge on the role of microorganisms involved the "Bryndza" ripening process may provide valuable data on its quality and safety. In our study, the "Bryndza" made from pasteurized ewes milk was studied towards total count of bacteria, coliforms bacteria, enterococci, lactic acid bacteria, and microscopic filamentous fungi. All those groups of microbiota were detected using classical microbiological methods and identified using mass spectrometry. A total of 3,758 isolates were identified with score higher than 2.00. Altogether, 13 families, 24 genus, and 44 species of microbiota were identified in Slovak cheese "Bryndza." The most often isolated species were yeasts Yarrowia lipolitica and Dipodascus geotrichum and the lactic acid bacteria Lactobacillus paracasei subsp. paracasei.

Determination of volatile organic compounds in Slovak bryndza cheese by the electronic nose and the headspace solid-phase microextraction gas chromatography-mass spectrometry

The aim of the present study was to describe volatile organic compounds of the traditional Slovak bryndza cheese determined by using an electronic nose (e-nose) and a gas chromatography mass spectrometry (GCMS) with head-space solid phase microextraction (HS-SPME). For the first time, e-nose based on the gas chromatography principle with a flame ionization detector was described to identify and quantify aroma active compounds of bryndza cheese from Slovakia. The e-nose detects aroma compounds of very small concentrations in real-time of a few minutes and identifies them by comparing Kovats´ retention indices with the NIST library. Bryndza cheese produced from unpasteurized ewe´s milk and from a mixture of raw ewe´s and pasteurized cow´s types of milk were collected from 2 different Slovak farms beginning in May through to September 2019. The flavour and aroma of bryndza cheese are apparently composed of compounds contained in milk and the products of fermentation of the substrate by bacteria and fungi. Regarding volatile organic compounds, 25 compounds were detected and identified by an electronic nose with a discriminant >0.900 with ethyl acetate, isopentyl acetate, 2-butanone, acetic acid, butanoic acid, and butane-2,3-dione confirmed by gas chromatography. We confirm the suitability of the electronic nose to be used for monitoring of bryndza cheese quality.

The Impact of Different Factors on the Quality and Volatile Organic Compounds Profile in "Bryndza" Cheese

The aim of this study was to evaluate the influence of different factors on the basic physicochemical and microbiological parameters, as well as volatile organic compounds of traditionally (farm) and industrially produced "bryndza" cheese. The samples were obtained from eight producers in different areas of Slovakia during the ewe's milk production season, from May to September. The physicochemical parameters set by the legislation were monitored by reference methods. The "bryndza" cheese microbiota was determined by using the plate cultivation method. There was analysis of volatile organic compounds carried out by electronic nose, as well as gas chromatography mass spectrometry. Seasonality and production technology (traditional and industrial ones) are the main factors that affect the standard quality of "bryndza" cheese. Lactic acid bacteria were dominated from bacterial microbiota, mostly presumptive lactococci, followed presumptive lactobacilli and enterococci. The numbers of coliform bacteria were higher in traditionally produced "bryndza" cheese than in industrially produced "bryndza" cheese. The presence of Dipodascus geotrichum was detected in all samples. There were key volatile organic compounds such as ethyl acetate, isoamyl acetate, 2-butanone, hexanoic acid, D-limonene, and 2,3-butanedione. The statistically significant differences were found among "bryndza" cheese samples and these differences were connected with the type of milk and dairies.