Milk Concentrations Research Articles

Macronutrient concentrations in human milk beyond the first half year of lactation: a cohort study

ObjectiveHuman milk composition is dynamic. While extensive research has focused on its macronutrient concentrations during the first 6 months of lactation, limited research exists for extended lactation periods. This study...

The Effect of Cannabis Consumption During Lactation on the Macronutrient Concentrations in Breast Milk

The Effect of Cannabis Consumption During Lactation on the Macronutrient Concentrations in Breast Milk

Improving the functionality of biosensors through the use of periodic and quasi-periodic one-dimensional phononic crystals

Abstract Resonant acoustic band gap materials have steered a new sensing technology era. This study is presented to investigate of the one-dimensional (1D) phononic crystals (PnCs), involving periodic, as well as quasi-periodic 1D layered PnCs represented as a highly sensitive biosensor to detect and monitor the quality of milk. In this regard, the numerical findings show that the examined periodic PnCs structure outperformed the quasi-periodic structure. In particular, it provides a wider phononic band gap and greater sensitivity as well. In addition, the quasi-periodic design (especially Fibonacci sequence S4) introduces multiple resonance peaks via transmission spectra, which may lead to some conflicts during the detection process. The findings reveal that the frequency of the resonant peak can effectively change with varied milk solution concentrations and temperatures. The optimized sensor is capable of differentiating between concentrations ranging between 0 and 50 % with a 10 % step, and it can also differentiate between temperatures, which range between 5 °C and 50 °C. This makes it ideal for precise detection of other liquids and solutions. The sensor performs efficiently for all milk solution concentrations. Here, the findings demonstrated that the examined defective PnC structure exhibited the most favorable sensitivity of the value of 94.34 MHz, so it showed the highest sensitivity when varying milk concentrations. In addition, the configurated sensor provided high QF and FOM values of 3,853.645161 and 157.42, respectively. On the other hand, the sensor performs very well for all temperatures of the milk solution. As such, the S 4 quasi-periodic structure is characterized as the optimal sensor structure when varying temperatures, introducing a sensitivity of 4.78 MHz/°C, QF of 4,278.521, and FOM of 7.48 °C−1.

Review of hemp components as functional feed and food ingredients: impact on animal product quality traits and nutritional value

This review examined the potential of hemp components as functional feed and food ingredients, focusing on their impact on the quality and nutritional value of animal products. Following hemp legalization, there was growing interest in its potential to enhance animal diets and processed animal products due to its rich nutritional profile, including high levels of polyunsaturated fatty acids (PUFA), essential amino acids, and fibre. Incorporating hemp components into feed for monogastric animals, particularly poultry, improved lipid stability, sensory attributes, and the fatty acid composition of meat and eggs. Hemp supplementation for ruminants, especially in goats, increased PUFA and conjugated linoleic acid (CLA) content in milk, improved meat tenderness, and enhanced oxidative stability. However, research on hemp supplementation for pigs and beef remained limited, indicating the need for further exploration of these species. Hemp cake, rich in protein, fibre, and essential fatty acids, was the most widely used hemp component due to its economic viability, nutritional benefits, and sustainability, contributing to improved meat and milk quality. Regulatory concerns about the transfer of tetrahydrocannabinol (THC) residues in the produced animal products restricted the use of hemp biomass. In processed animal products, hemp components were studied for their potential to enhance nutritional value, replace animal fats, and serve as natural preservatives. Although they improved the fatty acid profile and antioxidant properties of meat products, challenges such as textural changes and increased lipid oxidation needed to be addressed for optimal use. Limited studies on dairy products indicated promising nutritional enhancements, but textural issues could impact consumer acceptance. In conclusion, hemp components show significant potential for improving the quality and nutritional value of animal products. Further research is necessary to address regulatory, sensory, and formulation challenges and to expand their application across different animal species and processed animal products.

Artificial Neural Network Modeling to Predict Electrical Conductivity and Moisture Content of Milk During Non-Thermal Pasteurization: New Application of Artificial Intelligence (AI) in Food Processing

This study proposed applying artificial intelligence (AI) to predict the actual electrical conductivity (EC) of raw and pasteurized milk using moderate electric field (MEF) based on the electric field strength (EFS) and mass flow rate (MFR) along with modeling moisture content (MC) based on the EC. To this end, an artificial neural network (ANN) was implemented for conventionally (CP) and non-thermally (NP) pasteurized milk. The findings indicated no significant difference (p > 0.05) between the experimental and predicted data for EC and MC. The MFR and EFS affected the actual EC. The raw milk samples had an EC of 0.468812–0.46913 S/m and MC of 87.3218–87.35941%, while these values in NP pasteurized milk were 0.457441–0.638224 S/m and 87.33986–87.40851%. With correlation coefficients (R) of 0.736478106–0.951840323 and mean square errors (MSE) of 0.005539–0.0064, the ANN accurately predicted the raw and pasteurized milk MC based on the EC using the sixth-order polynomial model and the EC based on the EFS and MFR using a quadratic model. The EC of pasteurized milk by NP was significantly (p < 0.05) lower than that of CP and raw dairy by 15.44% and 11.30%, respectively. The results show that the EFS and MFR might be used for the online assessment of milk’s physical attributes (e.g., EC), followed by using the assessed parameter to determine other properties (e.g., MC) by developing AI approaches based on optimized models. These observations showcase the innovative use of ANN-based AI to predict milk’s EC and MC accurately. Integrating such AI platforms into non-thermal food processing could eventually develop more sustainable food production and enhance food security and quality through process innovation and sustainable manufacturing, contributing to the industrial revolution and sustainable development goals.

Analysis of the nutritional composition of Bahraini breed camel (Camelus dromedarius) milk: fatty acid, mineral, phenolic, and antioxidant content

Camels live under extremely arid conditions, yet they can produce more milk than any other animal in the desert ecosystem. They also have a longer lactation duration as well as low nutrition requirements. This study aims to determine the fatty acids profile, minerals, antioxidant activity and total phenols/flavonoids content, in camel milk of the species Camelus dromedarius in Bahrain. Gas chromatography was employed to analyze the fatty acid methyl esters obtained after the extraction of fatty acids. Mineral concentrations were measured by an Inductively Coupled Plasma Optical Emission Spectrometer. Antioxidant measurements included total phenolic content by the Folin-Ciocalteu method, total flavonoid contents by AlCl3 colorimetric method, and total antioxidant activity by the ferric reducing antioxidant power assay. The fatty acids analysis (median(interquartile range) %) showed that the most predominant fatty acids were unsaturated fatty acids (50.40(6.76) %), which were slightly higher than saturated fatty acids (49.60(12.17) %). The most abundant saturated fatty acids were C16:0 (26.73(6.73) %), C18:0 (12.32(4.28) %), and C14:0 (10.55(2.86)%). Monounsaturated fatty acid 18:1n9 was 31.5(5.66) %, and 16:1n7 was 12.75(2.19)%, while the major omega-3 was C18:3n3 (3.91(0.71) %). The main omega-6 were C18:2n6 and C18:3n6, accounting for 1.30(0.35) % and 0.94(0.21) %, respectively. The mineral content of camel milk varied, with the presence of macro minerals such as calcium (699.60 mg/L), sodium (855.18 mg/L), magnesium (9.33 mg/L) and potassium (87.09 mg/L). The results showed that camel milk has considerable values of total antioxidant activity (4.75(1.71) mmol/g), total phenolic contents (20.24(11.18) mg GAE/L) and total flavonoid contents (31.74(20.72) mg CE/L). In conclusion, although the (poly)phenol content in camel milk is relatively lower compared to certain plant-based sources, it can represent a good source of antioxidants, in addition to a significant content in unsaturated fatty acids and minerals, further enhancing its nutritional value for human health.

Immunological quality of colostrum and specific antibodies against enteropathogens in the colostrum and transition milk of crossbred Gir × Holstein cows.

Colostrum management is crucial for enhancing the immune response against enteropathogens and the survival of dairy calves during the first few weeks of life. However, few physiological studies have investigated the dynamics of general and specific immunoglobulin G (IgG) content in cow milk during early lactation stages, particularly in that of crossbred Gir × Holstein dairy cows, the most predominant dairy cattle population in tropical countries, such as Brazil. Therefore, this study evaluated the effects of parity and milking order on the volume and quality of colostrum, transition milk, and mature milk in crossbred Gir × Holstein cows using three traditional on-farm tests. The dynamics of IgG in the mammary secretions and the specific antibody levels against enteropathogens were also determined using sandwich enzyme-linked immunosorbent assay (ELISA) during the early stages of lactation. Fifty healthy Gir × Holstein cows were divided into two groups based on parity number, i.e., primiparous (n = 18) and multiparous (n = 33). They were monitored from the first to the 43rd milking. The colostrum volume and quality were evaluated using a colostrometer, Brix refractometer, and Colostro Balls after the first milking, in addition to the colostral IgG levels measured using sandwich ELISA as a reference standard. On-farm tests showed that the colostrum samples obtained from Gir × Holstein cows exhibited an optimal colostrum quality based on the literature criteria, regardless of parity number; however, the IgG mass was higher in the colostrum of multiparous (201 ± 67.03g) cows than in that of primiparous (144 ± 32.40g) cows. The volume and composition of transition and whole milk were also assessed at the second to ninth, 11th, 13th, 15th, 29th, and 43rd milkings. Multiparous cows produced higher volumes of transition milk than primiparous cows. In addition, multiparous cows exhibited a higher total solids percentage in their postpartum mammary secretions than primiparous cows. A higher percentage of inhibition of specific antibodies against Escherichia coli K99 was observed in the blood serum of multiparous cows than in that of primiparous cows. The volume and composition of mammary secretions changed over time; milk production increased, whereas total solids, total IgG, and specific antibody levels against most enteropathogens decreased, regardless of parity. Additionally, an association between parity and time was observed with respect to milk yield, the Brix score (%), and specific antibody levels against the Clostridium perfringens alpha toxin in mammary sections and against coronavirus and rotavirus in blood samples. This association indicated higher values in multiparous cattle than in primiparous cattle at specific time points. In conclusion, this study reveals postpartum time-dependent changes in the physiological and immunological components in the mammary secretions and blood of crossbred Gir × Holstein cows from the first to the 43rd milking. These results will contribute to the development of future research in Gir × Holstein-specific neonatology, which is genetically adapted to tropical and subtropical countries.

Heat Transfer Characteristics of Cryogenically Frozen Kulfi (A Dairy Dessert)

Kulfi was frozen from concentrated milk as well as from reconstituted dry mix with solids content of 60%. The convective heat transfer coefficients during freezing of kulfi by deep freeze and cryogenic methods were determined using one-dimensional transient heat conduction equation. The heat transfer coefficient for cryogenic freezing of kulfi from milk and dry mix concentrates was 210.57 W m-2K-1 and 216.84 W m-2K-1, respectively when compared to 8.33 W m-2K-1 for conventional deep-frozen kulfi. Freezing was achieved in 267 min in deep freeze method, while it reduced to just 185-190 s under cryogenic conditions. The freezing time was predicted using empirical equations, and the prediction accuracies were compared. Cryogenic freezing was nearly 87.66 times faster than deep freezing, and Pham’s model best-predicted the freezing time. Organoleptic evaluation using fuzzy-logic revealed that the order of ranking of quality attributes of kulfi was body and texture (highly important) > melting characteristics (highly important) > flavour and taste (highly important) > colour and appearance (important), and cryogenically frozen kulfi was statistically (p<0.05) superior to conventionally frozen kulfi.

Effect of macromolecules on the viscosity of whole condensed milk

The viscosity of a fluid refers to the resistance to flow, such as in the case of whole condensed milk. Condensed milk is a product created by partially dehydrating milk, concentrated milk, or reconstituted milk, and then sugar is added. Its fat and protein content can be adjusted to meet specific characteristics. The aim of this study was to evaluate the effect of macromolecules on the viscosity of various brands of whole condensed milk. The brands of whole condensed milk analyzed were classified as LCA, LCB, LCC, LCD, and LCE, with a total of 50 samples from different batches. The viscosity was measured using the Ford cup method, which was validated through tests for linearity, detection limit, quantification limit, and repeatability. The physicochemical tests included viscosity, soluble solids (oBrix), moisture, protein, lipids, RMF, carbohydrates, total caloric value, and SNG. The main findings showed that the LCC, LCD, and LCE brands had high levels of macromolecules (protein, lipids, and carbohydrates) and viscosity. Consequently, it was concluded that high concentrations of macromolecules in whole condensed milk result in increased viscosity of the product.

Population pharmacokinetic modelling of cetirizine concentrations in human breast milk-A contribution from the ConcePTION project.

Cetirizine is an antihistamine commonly used to treat allergic rhinitis and other allergic conditions. Cetirizine is often prescribed to breastfeeding mothers although there is limited information on infant exposure via breast milk. The aim of this study was to develop a popPK model based on data from a lactation study to predict cetirizine breast milk concentrations and estimate the relative infant dose (RID) in a breastfed infant. A popPK model was developed in NONMEM on data from a human lactation study including 35 women using cetirizine or levocetirizine while breastfeeding. Serial samples of breast milk were collected (n = 205) and the cetirizine concentrations quantified using a validated LC-MS/MS method. A one-compartment model of cetirizine in breast milk was developed and employed to calculate the relative infant dose (RID). Covariates related to the maternal characteristics and breastfeeding patterns were evaluated in the model; only milk sampling pumping duration was found to be a significant covariate, with an increasing pumping duration leading to an increased apparent milk volume of distribution (Vm). The mean RID was 1.99% with the highest RID being 3.36% at Cmax. PopPK modelling could be used to estimate infant exposure to cetirizine via breast milk. The low predicted exposure in infants supports that cetirizine is compatible with breastfeeding.

Interactions between blood lead (Pb) concentration, oxidative stress, cellular immune response and reproductive status in livestock from a mining area

Chronic exposure to lead (Pb) in livestock grazing in abandoned mining areas affects animal welfare and productivity, as well as represents a significant food safety risk. Here, we evaluate the physiological effects of Pb exposure in goats maintained under extensive farming conditions in a non-remediated mining area. We monitored blood, fecal, and milk Pb levels in two groups of goats, pregnant (n=17) and lactating (n=24), kept in different enclosures with high soil Pb concentrations (geometric means of 270 and 143 μg/g, respectively) in Sierra Madrona mining district (Spain). We also studied the influence of Pb exposure on the ability to mount a cellular immune response, and on oxidative stress and biochemical biomarkers measured in blood. Blood Pb concentration was higher in pregnant than in lactating goats, but this difference was not observed in fecal Pb concentration. Pb levels in feces and milk concentrations were correlated with those measured in blood, with 11% of milk samples showing Pb concentrations above the maximum level (ML) for Pb in raw milk established by the EU (0.02 μg/g wet weight). Animals with increased blood Pb levels showed reduced concentrations of retinol in plasma, but these Pb levels did not affect the cellular immune response. The stimulation of the cellular immune response in lactating goats was associated with an increase in blood Pb and calcium (Ca) levels. The reproductive status and age of goats significantly affected several oxidative stress, antioxidants and plasma biochemistry variables. Goats grazing on soils contaminated by past Pb mining activities may be susceptible to detrimental health effects mediated by retinol deficiency. In view of the detected transfer of Pb through milk, special attention should be paid to the food safety of derived products (i.e. cheese).

Maltogenic amylase and glucosyltransferase synergistically control the chain structure of rice starch and their effects on rheological properties and functional characteristics of rice milk

Maltogenic amylase (MA) and glucosyltransferase (TG) were used synergistically for the development of rice milk products with low glycemic index (GI), and its storage properties and nutritional functions were evaluated. The structural results showed that MA and TG treatment could effectively reduce the molecular weight of rice starch and increases its overall branching degree, which further affected the storage and nutritional properties of rice milk products. Compared with gelatinized rice milk and rice milk treated with MA or TG, MTRM (treated with MA and TG) had lower paste viscosity, stable storage modulus, and stronger ability to bind water during storage period, indicating that the dual-enzyme treatment significantly improved the retrogradation properties of rice milk and the anti-retrogradation rate reached 76.12%. In vitro studies showed that dual-enzyme treatment significantly increased the resistant starch content of rice milk to 39.46%, thereby reducing its predicted glycemic index to 53.85, improving its antioxidant properties and contributing to the proliferation of short-chain fatty acids produced bacteria. Notably, MTRM significantly elevated butyrate content which showed a better prebiotic effect. This research provides new approaches for the preparation of low-GI rice-based beverages.

Reduction of tumor necrosis factor (TNF) in milk of women receiving anti-TNF antibody.

Tumor Necrosis Factor (TNF) are expressed in milk. Experimental data indicate enhanced brain growth and cognitive development in the mouse offspring given milk deficient in TNF and TNF-dependent chemokines. Although monoclonal antibodies against TNF (TNFmAb) are used during breastfeeding due to minimal milk excretion, whether it affects endogenous TNF levels in human milk is unclear. A prospective cohort study was conducted in 26 breastfeeding women with inflammatory bowel disease (IBD) and 31 non-IBD women. Milk TNF and related chemokines were measured at 5-6 weeks postpartum (early-lactation point) as a primary endpoint and further determined at 13-14 weeks postpartum. In a subset of their infants, neurocognitive development was assessed at 12 and 18 months of age using Bayley-III tool. While milk TNF levels were not significantly different between the control and those with IBD, women with IBD receiving TNFmAb showed 70% lower median milk TNF than those without TNFmAb (P = 0.019) at early lactation period. TNF-dependent chemokines (MIP-1β and IP-10) also showed similar patterns. Neurocognitive development of the infants was not significantly different among the groups. Women with IBD receiving TNFmAb show significantly lower milk TNF/chemokines at 5-6 weeks postpartum than those without TNFmAb. gov NCT03397108. We found that milk concentrations of Tumor Necrosis Factor (TNF) and TNF-dependent chemokines (MIP-1β and IP-10) are low in women with inflammatory bowel disease who are receiving anti-TNF monoclonal antibody (TNFmAb), compared to those without concurrent anti TNF therapy. While maternal use of TNFmAb during breastfeeding is considered inconsequential to infant health due to their low levels of milk excretion, it affects profiles of endogenous cytokines in milk. Our findings provide a rationale to investigate human implications of the animal data in the literature that suggest enhancement of neurocognitive development of the offspring fed with milk deficient in TNF-dependent chemokines.

Rapid detection and spectroscopic feature analysis of mineral content in camel milk using fourier-transform mid-infrared spectroscopy and traditional machine learning algorithms

Camel milk is rich in nutrients and bioactive factors, with mineral content generally higher than that of cow milk, but there is currently no internationally established, rapid, batch-testing method for the mineral content. This study collected samples of camel milk from 113 locations in Xinjiang, China. For the first time internationally, based on the true mineral values determined by ICP-OES (Inductively Coupled Plasma Optical Emission Spectroscopy) and the extracted mid-infrared spectra data, a quantitative prediction model for 10 key minerals (Ca, Fe, K, Mg, Mn, Na, P, Sr, Zn, and Se) was established using Fourier-Transform Mid-Infrared Spectroscopy (FT-MIRS) and the traditional machine learning algorithm Partial Least Squares Regression. The Rt2 of the test set ranged from 0.61 to 0.91, RMSEt ranged from 2.21ug/kg(Se) to 197.08 mg/kg(K) and the RPDt from 1.59 to 3.28. In addition, the distribution, patterns, and correlations of mineral-related characteristic wavenumbers in camel milk were summarized. This study opens a new avenue for the rapid detection of minerals in camel milk and fills the research gap in in using FT-MIRS to detect mineral content in camel milk.

Cow Milk Fatty Acid and Protein Composition in Different Breeds and Regions in China

Cow milk is rich in proteins, fats, carbohydrates, and minerals; however, its precise nutrient content varies based on various factors. In the current study, we evaluated the differences in the fatty acid and protein contents of milk and the factors associated with these differences. To achieve this, samples were collected from seven types of cows in different regions. These included samples from three dairy breeds: Chinese Holstein milk from Beijing, China (BH), Chinese Holstein milk (HH) and Jersey milk (JS) from Hebei province, China; and four dairy/meat breeds: Sanhe milk (SH) from Inner Mongolia Autonomous Region, China, Xinjiang brown milk (XH) and Simmental milk (SI) from Xinjiang Uygur Autonomous Region, China, and Shu Xuanhua milk (SX) from Sichuan province, China. Breed significantly affects total fat, fatty acid, and protein contents. Additionally, geographic region significantly affects the contents of different fatty acids, α-lactalbumin, and lactoferrin. JS has the highest total fat and casein contents. XH samples contain significantly higher unsaturated fatty acid content than BH samples and do not differ significantly from JS. Additionally, the low β-lactoglobulin and high lactoferrin contents in XH samples may be favorable for the growth and development of infants. Our results may inform the development of dairy products from different cow breeds and advance the process of accurate breed identification.

Effect of Herbal Liver-tonic Supplements on Production Performance in HF Dairy Cattle

A study was conducted to observe the influence of herbal liver-tonic supplementation on milk production, liver function and feed intake in HF crossbred dairy cattle at field level. This study was carried out in 24 HF cattle and these were randomly grouped into three groups viz. Group 1 served as control group, Group II served as Treatment -I (supplemented with polyherbal liver tonic @ 30ml/day) and Group III as Treatment-2 (supplemented with polyherbal liver tonic @ 45ml/day). Day 1 to 7 is considered as before treatment, Day 8 to 17 as treatment period and day 18 to 32 as after treatment. The blood collected during study period and stored at -20 °C until further analysis. The data were also regularly recorded for milk production, SNF Content of milk, feed intake. Statistical analysis of result revealed that herbal liver-tonic supplementation showed non-significant (P>0.05) difference on liver enzymes profile. Statistically no significant difference is also noted on milk production, milk fat and SNF Content in HF Cattle at field conditions.

The Pharmacokinetics of Subcutaneous Eprinomectin in Plasma and Milk in Dry Dairy Cattle.

Parasitic infections in dairy cattle reduce herd immunity, milk production, and conception rates. This leads to higher production costs, compromised animal welfare, and increased interest in extralabel drug use. The extralabel use of anthelmintics poses food safety risks for consumers since appropriate withdrawal intervals in milk have yet to be established. Although topical eprinomectin has no milk withdrawal time, more research is needed to determine the residues present in milk after subcutaneous administration. This study aimed to characterize the pharmacokinetics of injectable eprinomectin in dry dairy cows. We hypothesized that, when given at the labeled dose, eprinomectin residues in dry dairy cattle would be below the FDA milk tolerance at the onset of lactation. Plasma was collected daily from 13 mature dairy cattle for 7 days postadministration, followed by periodic samples for 90 days. After calving, milk was collected daily until 90 days. Eprinomectin concentrations were measured using HPLC-fluorescence detection. The maximum eprinomectin concentration in plasma and milk was approximately 36 ng/mL 43 h after administration and 3 ng/mL at the onset of lactation, respectively. The low eprinomectin levels in milk collected from these lactating dairy cattle suggest that administering eprinomectin at dry-off is unlikely to result in violative residues. However, subcutaneous eprinomectin in lactating dairy cattle would be hard to justify unless there is evidence that the approved topical formulation is clinically ineffective.

Folic acid, cobalamin, and biotin concentrations in milk samples of sheep, goats, and cows

Milk is an important food obtained from mammals, containing almost all of the nutrients needed for metabolism. The vitamin composition of milk, the first food of mammals, is valuable data for the food industry and public health. This study aimed to determine the levels of folic acid (vitamin B9), cobalamin (vitamin B12), and biotin (vitamin B7) in different milk samples (cow, sheep, goat) using the ELISA method. For this purpose, milk samples from Holstein Cows (n:50), Awassi Sheep (n:50), and Kilis Goats (n:50) available for retail in the Şanlıurfa province of Turkey were collected and analyzed. In this study, the average folic acid content of sheep, goat, and cow milk was found to be 3.45 µg/100 mL, 7.23 µg/100 ml, and 6.64 µg/100 mL, respectively. The average cobalamin content of sheep, goat, and cow milk was 0.70 µg/100 ml, 7.43 µg/100 ml, and 0.58 µg/100 mL, respectively, while the average biotin content of sheep, goat, and cow milk was 2.21 µg/100 mL, 2.21 µg/100 mL, and 2.09 µg/100 mL, respectively. It was noted that the average biotin levels in sheep, goat, and cow milk did not differ significantly. However, significant differences were observed in the quantities of folic acid and cobalamin (P<0.05). Different levels of folic acid were found in milk samples from these three species. Cobalamin levels in goat milk samples were significantly higher, while biotin levels were similar in each milk sample of the species. This study underscores the importance of understanding and considering the diverse vitamin compositions of milk from different mammalian species to ensure comprehensive nutritional intake.

Comparison of methods for measurement of somatic cell count in goat milk

The aim of the study was to compare the efficiency of determining the number of somatic cell count in goat milk by different methods. Somatic cells in individual samples of milk from 28 goats were studied using analyzers "Somatos", "SomaCount Flow Cytometer" and by the counting method in milk films stained according to Romanovsky – Giemsa, May-Grünwald and with pyronin Y. For the counting of somatic cells in goat milk by Prescott and Breed method, it is recommended to stain milk films by the May-Grünwald method, because the cytoplasm and nuclei of somatic cells are clearly stained, and the cost of dyes is much less than the pyroninY method. When counting cells in milk films stained by any method, no samples with the SCC up to 100 ´ 103 cells/ml were found. Direct counting of somatic cells in milk films stained by any method reveals a greater number of cells than with the help of devices. It was found that the fat content in goat milk with SCC >3000 ´ 103 cells/ml is significantly higher (P < 0.05) compared to milk with SCC < 1000 ´ 103 cells/ml. The quality of goat's milk smears for counting of somatic cells quantity stained by the May-Grünwald method corresponds to the recommended method with pyronin Y, and the cost of dyes is 28.4 times lower. The distribution of somatic cell ranges is similar between different methods of staining smears, which once again proves the accuracy of the method of direct cell counting in milk films, although it is more labor-intensive than hardware methods.

Influence of the Blends of Sheep's and Goat's Milk on the Functional Properties and Volatile Compounds of Lighvan Cheese During Ripening: A Comparative Study

ABSTRACTIn this study, the influence of different ratios of sheep's to goat's milk (100:0, 75:25, 50:50, 25:75, and 0:100) on the content of functional metabolites and volatiles in Lighvan cheese throughout ripening was investigated. The samples were ripened under brine for 90 days and assessed in terms of variations in chemical composition, proteolysis, angiotensin‐converting enzyme, α‐amylase, and α‐glucosidase inhibitory activities, antioxidant power, total free amino acids, gamma amino butyric acid, free fatty acids, and volatile compounds. Results showed that by increasing the proportion of goat's milk, the samples exhibited higher antioxidant effect and inhibition of the angiotensin‐converting enzyme during ripening. After 90 days, an increase in α‐glucosidase and a slight decrease in α‐amylase inhibitory activities were observed in Lighvan cheese samples that were produced with 50%, 75% and 100% of goat's milk. In contrast, higher contents of sheep's milk led to a significant increase in the concentration of esters, terpenes and alcohols and a slight increase in gamma‐aminobutyric acid. The highest concentration of saturated and unsaturated fatty acids was observed in the cheese prepared with 100% raw sheep's milk after 90 days of ripening. The results revealed the possibility of making a functional white‐brined cheese by monitoring the type and ratio of the used milk and ripening time.