scholarly journals Microstructure of kajmak skin layer made during kajmak production

2020 ◽  
Vol 70 (3) ◽  
pp. 150-161
Author(s):  
Mira Radovanovic ◽  
Predrag Pudja ◽  
Vladimir Pavlovic ◽  
Jelena Miocinovic ◽  
Aleksandar Nedeljkovic
Keyword(s):  
Dairy Product ◽  
Whey Proteins ◽  
Skin Layer ◽  
Milk Composition ◽  
Fat Content ◽  
Protein Distribution ◽  
Compact Structure ◽  
Reducing Conditions ◽  
Sds Page ◽  
Lower Temperature

Kajmak is a unique dairy product with a long tradition in Balkan countries and the Middle East. Kajmak skin layers are formed during 60 minutes of kajmak production, influencing the quality and determining the structure of the final product. The influence of milk composition and heat treatments (75-95 °C/5min) on the composition, microstructure and protein distribution of kajmak skin layers was investigated in this study. Microstructure was determined using scanning electron microscopy (SEM), while the distribution of protein fractions was studied by SDS PAGE in reducing and non-reducing conditions. Kajmak skin layers obtained from milk treated at common intense heat regime were characterized with β-LG and α-LA mainly as disulfide-linked complexes, while lower temperature (75 °C) caused the presence of whey proteins in dominantly individual form. More severe treatments (85 °C, 90 °C and 95 °C) caused the full involvement of β-LG in the complexes, since a certain amount of α-LA was found as a monomer. The kajmak skin layer composition, severity of the applied milk heat treatment and the linked whey proteins exhibited a very strong influence on kajmak skin layer microstructure. The microstructure of kajmak skin layer with a low fat content and fat/protein (F/P) ratio was characterized by a compact structure with a dense protein matrix. High fat content and F/P ratio resulted in a dispersive form of the stretched protein network. Kajmak skin layers produced from milk with added whey proteins were characterized by fibrous, thread-like segments, due to the incorporated denatured whey proteins, especially linked β-LG.

Milk Composition in a Field Population of Red Kangaroos, Macropus Rufus (Desmarest) (Macropodidae: Marsupialia)

1996 ◽  
Vol 44 (2) ◽  
pp. 165 ◽  
Author(s):  
E Muths
Keyword(s):  
Whey Proteins ◽  
Milk Composition ◽  
Field Population ◽  
Sds Page ◽  
Macropus Rufus ◽  
Total Milk ◽  
Specific Proteins ◽  
Milk Solids

The composition of milk from early pouch life (0-40 days) to weaning (360 days) was determined in samples collected from a field population of red kangaroos, Macropus rufus (n = 150). Total milk solids increased from 11% at 0-40 days to 26% at permanent emergence from the pouch (235 days), then decreased towards weaning. Compared with other macropodids, milk from red kangaroos is relatively dilute. Carbohydrate concentrations increased from 2.0 to 6.2% at about Day 235 then declined while lipid concentrations increased from 3.9 to 10.3% over the course of lactation. Protein values increased from 5.0 to 7.0% prior to pouch emergence. Whey proteins were separated by means of SDS PAGE, identifying and confirming the presence of several phase-specific proteins. These results are similar to those reported for components of milk in captive red kangaroos and therefore confirm the general macropodid pattern of changing milk composition throughout lactation for a field population of red kangaroos.

scholarly journals Study on milk composition and milk protein distribution in Romanian Holstein cattle

2020 ◽  
Vol 23 (1) ◽  
pp. 13-21
Author(s):  
Rodica Ştefania Pelmuş ◽  
Cristina Lazăr ◽  
M. L. Palade ◽  
Mariana Stancu ◽  
C. M. Rotar ◽  
...  
Keyword(s):  
Milk Protein ◽  
Whey Proteins ◽  
Milk Proteins ◽  
Protein Composition ◽  
Holstein Cattle ◽  
Protein Distribution ◽  
Quality Indices ◽  
Milk Samples ◽  
Sds Page ◽  
Β Lactoglobulin

AbstractThe aim of this study was to determine milk quality indices as well as the milk protein composition in Romanian Holstein cattle raised under the conditions of experimental farm of INCDBNA-IBNA. The study was carried out on 22 milk samples. The types of different milk proteins were identified by SDS-PAGE technique. Sampling day and milk chemical composition were performed during the milking period of studied cattle. The quality indices were breed-specific for protein (3.38%) and higher for fat (4.39%).Milk proteins analysis of Romanian Holstein cattle separated by SDS-PAGE electrophoresis showed the presence of four major caseins (αs1-, αs2-, β- and k-casein) and two whey proteins (β-lactoglobulin, α-lactalbumin). The caseins accounted 77.28% of the total milk proteins, while the major proteins (β-lactoglobulin, α-lactalbumin) from the whey represented 22.72% of the total proteins. αs1-casein + αs2-casein had a higher expression (36.01%) followed by β-casein (31.45%), β-lactoglobulin (18.16%), k-casein (9.82%) and α-lactalbumin (4.56%). The most of milk samples was characterized by a medium expression level of both caseins and whey proteins

scholarly journals AB0050 A NOVEL METHOD FOR ISOLATION OF EXOSOMES FROM SYNOVIAL FLUID

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1057.2-1057
Author(s):  
Y. Liu ◽  
Y. Huang ◽  
Q. Huang ◽  
S. Sun ◽  
Z. Ji ◽  
...  
Keyword(s):  
Synovial Fluid ◽  
Western Blot ◽  
Biological Fluid ◽  
High Sensitivity ◽  
Protein Distribution ◽  
Sds Page ◽  
Close Relationship ◽  
Novel Method ◽  
Low Levels

Background:Exosomes in synovial fluid (SF) has a close relationship with the pathogenesis of rheumatiod arthritis. As a complex biological fluid, SF presents challenges for exosomes isolation using standard methods, such as ExoquickTM kit and ultracentrifugation.Objectives:The study aims to compared the quality of exosomes separated by ExoquickTM kit (TM), ExoquickTM kit+ExoquickTC kit (TM-TC), ultracentrifugation (UC) and TM-TC+UC(TM-TC-UC) from SF.Methods:Exosomes was separated by TM, TM-TC, UC and TM-TC-UC respectively. The size and concentrations of exosomes were detected by high sensitivity flow cytometry for nanoparticle analysis. Total protein and RNA were extracted from exosomes. SDS-PAGE was used to detect the protein distribution of exosomes. Western blot was used to examine the level of albumin and exosomes marker (TSG101 and CD81).Results:There was no statistic difference in the diameters of exosomes separated by the four methods. The concentrations of exosomes in TM, TM-TC, TM-TC-UC and UC were (5.65±0.93), (3.02±1.19), (1.67±0.25) and (4.61±0.73) *109Particles/mL. The protein concentrations of exosomes separated by the four methods were consistent with the concentrations of exosomes. SDS-PAGE showed that the protein distribution of exosomes separated by the four methods were different. Low levels of albumin were detected in TM-TC and TM-TC-UC, while high levels of albumin in TM and UC. Total RNA concentrations from exosomes in TM-TC was higher than other groups.Conclusion:TM-TC can be used to obtain higher quality exosomes from SF for the study of exosome-enriched components.References:[1]Helwa I, et al, A Comparative Study of Serum Exosome Isolation Using Differential Ultracentrifugation and Three Commercial Reagents. PloS one, 2017. 12(1): p. e0170628-e0170628.Figure 1.A: SDS-PAGE showed the protein distribution of exosomes; B: the detection of albumin, TSG101 and CD81 by western blot.Disclosure of Interests:None declared

Steam distillation of taints from cream: VIII. Effect of fat content of dairy product on deodorization process

1959 ◽  
Vol 26 (2) ◽  
pp. 113-122 ◽  
Author(s):  
F. H. McDowall
Keyword(s):  
Distribution Ratio ◽  
Steam Distillation ◽  
Dairy Product ◽  
Skim Milk ◽  
Fat Content ◽  
Threshold Concentration ◽  
Unit Weight ◽  
High Fat ◽  
Liquid Equilibrium ◽  
Commercial Practice

1. In commercial practice dairy liquids of fat contents ranging from 3 to 90% are subjected to deodorization by steam distillation treatment.2. Increase in fat test of cream causes a rise in the vapour/liquid equilibrium coefficient for tainting substances of low butterfat/skim-milk distribution ratio, and a fall for substances of high-distribution ratio, in cream.3. Increase in fat content of cream reduces the amount of tainting substance in the cream per unit weight of butterfat in the cream, for substances of all butterfat/skim-milk distribution ratios.4. Separation of milk to cream of a high fat content greatly facilitates the elimination of substances of low butterfat/skim-milk distribution ratio from the cream and butter.5. Variation in temperature of separation, by its effect on the distribution ratio for tainting substances, could affect the content of these substances in the final cream, and could possibly cause a change in the character of the cream.6. In the partition of tainting substance between butter and buttermilk in the churning process, fat content of cream affects the proportion of residual taint passing from the treated cream into the butter.7. It is pointed out that, because of the effect of salt in increasing the vapour/liquid equilibrium coefficient of some steam volatile substances, the threshold concentration for a tainting substance in butter can be expected to vary with variation in the rate of salting of the butter.

The dynamics of individual whey protein concentrations in cows’ mammary secretions during the colostral and early lactation periods

2018 ◽  
Vol 86 (1) ◽  
pp. 88-93 ◽  
Author(s):  
Raquel F.S. Raimondo ◽  
Juliana S.P. Ferrão ◽  
Samantha I. Miyashiro ◽  
Priscila T. Ferreira ◽  
João Paulo E. Saut ◽  
...  
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Whey Proteins ◽  
Total Proteins ◽  
Mature Milk ◽  
Rennet Coagulation ◽  
Sds Page ◽  
Different Types ◽  
Biuret Method ◽  
Jersey Cows ◽  
Β Lactoglobulin

AbstractThe bovine whey consists of more than 200 different types of proteins, of which β-lactoglobulin, α-lactalbumin, serum albumin, immunoglobulins and lactoferrin predominate. However, their concentrations are not stable due to the existence of protein dynamics during a transition from colostrum secretion to mature milk. To evaluate the dynamics of whey proteins of Jersey cows during a colostral phase and first month of lactation and an influence of the number of lactations, 268 milk samples from 135 Jersey cows were selected through a clinical evaluation. Whey was obtained by rennet coagulation of the mammary secretion. The concentration of total proteins was determined by the biuret method and their fractions were identified by 12% dodecyl sulfate-polyacrylamide gel electrophoresis (12% SDS-PAGE). Maximum concentrations of all protein fractions were observed in the first 12 h of lactation, reducing over the course of the study. Modification of the protein predominance was also observed. The transition from colostrum secretion to milk occurred between 24 and 72 h postpartum. There was an influence of the number of lactations on the dynamics of whey proteins, indicating that multiparous cows had better immunological and nutritional quality when compared to primiparous cows.

Diphenyl diselenide subcutaneous supplementation of dairy sheep: effects on oxidant and antioxidant status, inflammatory response and milk composition

2019 ◽  
Vol 59 (3) ◽  
pp. 461 ◽  
Author(s):  
Angelisa H. Biazus ◽  
Chrystian J. Cazarotto ◽  
Gustavo Machado ◽  
Nathieli B. Bottari ◽  
Mariana S. Alves ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Interleukin 10 ◽  
Milk Composition ◽  
Fat Content ◽  
Control Group ◽  
Lactation Period ◽  
Diphenyl Diselenide ◽  
Dairy Sheep ◽  
Positive Effects ◽  
Anti Inflammatory

Diphenyl diselenide ((PhSe)2) is a organoselenium compound with potent antioxidant properties. Therefore, the aim of the present study was to evaluate whether subcutaneous supplementation of (PhSe)2 in dairy sheep has positive effects on milk composition, as well as on the prevention of oxidative stress and exacerbated inflammatory response. For this, 16 primiparous recently calved sheep were divided into the following two groups, with eight animals in each: Group A, the control group; and Group B, the group subcutaneously supplemented with five doses of (PhSe)2 of 3.0µmol/kg each every 7 days. Blood samples from supplemented animals showed increased concentration of antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase and glutathione-S-transferase), and reduced reactive oxygen species and lipid peroxidation, which prevented oxidative damage in the lactation period, as well as increased seric interleukin-10, an anti-inflammatory cytokine. In the sera, supplemented animals showed increased total antioxidant capacity and ferric-reducing ability of plasma compared with the control group. As a consequence, supplemented animals showed increased antioxidant variables, as well as reduced protein oxidation in milk samples. Moreover, milk from supplemented sheep showed a higher fat content, and lower total protein and lactose contents in some periods in the study, than did not-supplemented ewes. Seric concentrations of interleukin-1 were lower on Days 30 and 45 in supplemented animals, as well as the concentrations of tumour necrosis factor α in all periods, than were those in the control group, whereas the interleukin-10 concentrations were higher. Thus, dairy sheep supplementation of (PhSe)2 activated antioxidant and anti-inflammatory responses, and increased milk fat content. Moreover, this protocol increased the antioxidant and, consequently, reduced the oxidant concentration in milk, which is desirable for product quality.

scholarly journals Effect of herb mixture supplementation in ratio on milk yield, milk composition and its technological suitability

2002 ◽  
Vol 18 (3-4) ◽  
pp. 15-20 ◽  
Author(s):  
T. Grega ◽  
M. Sady ◽  
J. Kraszewski
Keyword(s):  
Milk Yield ◽  
Dry Matter ◽  
Saturated Fatty Acids ◽  
Whey Proteins ◽  
Heat Stability ◽  
Milk Composition ◽  
Black And White ◽  
Milk Cows ◽  
Fermentation Test ◽  
Experimental Group

Investigations were carried out on milk cows of Black -and- White breed being in 2-nd lactation 30-120 day after parturition. Experiment was performed during winter feeding season (corn silage, fodder beet silage, super beet pulp, concentrate, meadow hay). Cows of the experimental group received supplement (5% of concentrate) of the herb mixture in feeding ratio. The composition of this mixture was as follows: Urtica dioica, Fructus carvi, Pradix teraxaci, Agrimonio eupatoria, Matrica chamomilla. The obtained results show that supplementation of the diet by herb mixture induced increase of the following parameters: milk yield (+2 kg), fat content (+0,04%), protein content (+0,06%), citric acid (+0,10%), whey proteins (+0,02%), casein (+0,04%), dry matter (+0,12%), non fat dry matter (+0,07%). It was stated that in the experimental milk non-saturated fatty acid level was higher (+20%), in opposite to lower level of saturated fatty acids (-15%) and total cholesterol (-25%). The beneficial effect of herb mixture supplementation on the results of rennet-fermentation test, fermentation test, Sehern' s test and heat stability was stated in the experimental group milk.

scholarly journals Tyrosine phosphorylation of P-selectin in intact platelets and in a disulphide-linked complex with immunoprecipitated pp60c-src

1994 ◽  
Vol 299 (3) ◽  
pp. 613-621 ◽  
Author(s):  
P W Modderman ◽  
A E G K von dem Borne ◽  
A Sonnenberg
Keyword(s):  
Tyrosine Phosphorylation ◽  
Cell Activation ◽  
Secretory Granules ◽  
Protein S ◽  
Kinase Assay ◽  
Intact Cells ◽  
Tyrosine Residues ◽  
Reducing Conditions ◽  
Sds Page

P-selectin is a 140 kDa membrane glycoprotein found in secretory granules of platelets and endothelial cells where it is rapidly translocated to the plasma membrane upon cell activation. It then functions as a receptor for various types of leucocytes. Metabolic labelling of resting platelets with 32Pi showed that P-selectin is primarily phosphorylated on serine residues, although some tyrosine phosphorylation was observed as well. However, tyrosine phosphorylation of P-selectin was greatly stimulated by treatment with the permeating phosphatase inhibitor, pervanadate. When P-selectin immunoprecipitates were incubated with [gamma-32P]ATP (in vitro kinase assay), a fraction of P-selectin was phosphorylated on its tyrosine residues by a co-precipitated kinase. P-selectin phosphorylated in vitro co-migrated with 140 kDa surface-labelled 125I-P-selectin during SDS/PAGE under reducing conditions. Under non-reducing conditions, however, phosphorylated P-selectin was disulphide-linked to unknown protein(s) in a 205 kDa complex. In vitro kinase assays of the most abundant platelet tyrosine kinase, pp60c-src, demonstrated the presence of similar 140 and 205 kDa phosphorylated proteins in SDS/PAGE under reducing and non-reducing conditions respectively. Extraction and reprecipitation studies with proteins phosphorylated in vitro indicated that P-selectin and pp60c-src form a 205 kDa 1:1 disulphide-linked complex. In the complex, pp60c-src autophosphorylation is inhibited and P-selectin is phosphorylated on tyrosine residues. As protein disulphides in the cytoplasm of intact cells are extremely rare, our results suggest that P-selectin and pp60c-src, which co-localize in platelet dense granules, may be non-covalently associated and spontaneously form disulphide bridges during lysis. In addition, the observed tyrosine phosphorylation of P-selectin in intact platelets suggests that its function might be regulated by phosphorylation by pp60c-src.

Peculiarities of extraction of β-lactoglobuline in protein mineral concentrates at electroactivation of whey

2020 ◽  
Vol 2 (1) ◽  
pp. 52-68
Author(s):  
Mircea BOLOGA ◽  
Elvira VRABIE ◽  
Irina PALADII ◽  
Olga ILIASENCO ◽  
Tatiana STEPURINA ◽  
...  
Keyword(s):  
Protein Content ◽  
Whey Proteins ◽  
Sodium Dodecyl ◽  
Total Protein Content ◽  
Treatment Regimens ◽  
Sds Page ◽  
Different Types ◽  
Lower Protein ◽  
Β Lactoglobulin ◽  
Excellent Source

Introduction. Whey is a by-product and an excellent source of proteins that is rather aggressive due to a large amount of organic substances it contains. The electro-activation of whey applied in the experiments is a wasteless method that allows the va-lorification of all whey components. β-lactoglobulin (β-Lg) makes up 50% of the whey proteins and 12% of the total protein content in milk. Material and methods. The recovery of β-Lg in protein-mineral concentrates (PMC) by electro-activation processing of different types of whey with different initial protein content was investigated in seven configurations. The recovery of protein fractions in the PMCs were analyzed via electrophoresis with sodium dodecyl sulfate (SDS-PAGE) and 15% non-denaturing polyacrylamide gel (PAAG).      Results. Whey electro-fractionation and the obtaining of PMCs with predetermined protein content, namely of β-Lg, were studied on three whey types, processed at different treatment regimens and in seven configurations. The proper management of electroactivation by varying the treatment regimens will allow the electro-fractionation of different types of dairy by-products. Conclusions. The maximum amount of β-Lg recovered in PMCs on electroactivation is  66-71% depending on the processed whey and on the treatment regimens. Obviously, the extraction of β-Lg from initially lower protein content shows a higher recovery degree of β-Lg. The registered temperatures allows formation of PMCs without thermal denaturation.

scholarly journals Determination of whey proteins in different types of milk

2014 ◽  
Vol 83 (1) ◽  
pp. 67-72 ◽  
Author(s):  
Lenka Ruprichová ◽  
Michaela Králová ◽  
Ivana Borkovcová ◽  
Lenka Vorlová ◽  
Iveta Bedáňová
Keyword(s):  
High Performance ◽  
Dairy Product ◽  
Whey Proteins ◽  
Reversed Phase ◽  
Cow’S Milk ◽  
Cow's Milk ◽  
Goat’S Milk ◽  
Different Types ◽  
Goat's Milk ◽  
Β Lactoglobulin

Protein analysis is very important both in terms of milk protein allergy, and of milk and dairy product adulteration (β-lactoglobulin may be an important marker in the detection of milk adulteration). The aim of this study was to detect major whey proteins α-lactalbumin and β-lactoglobulin and their genetic variants by reversed-phase high-performance liquid chromatography. Milk samples from cows (n = 40), goats (n = 40) and sheep (n = 40) were collected at two farms and milk bars in the Czech Republic from April to June 2010. The concentration of α-lactalbumin was higher in goat’s milk (1.27 ± 0.05 g·l-1, P < 0.001) and cow’s milk (1.16 ± 0.02 g·l-1, P = 0.0037) compared to sheep’s milk (0.95 ± 0.06 g·l-1); however, concentration of α-lactalbumin in goat’s milk and cow’s milk did not differ significantly (P < 0.05). Goat’s milk contained less β-lactoglobulin (3.07 ± 0.08 g·l-1) compared to cow’s milk (4.10 ± 0.04 g·l-1, P < 0.001) or sheep’s milk (5.97 ± 0.24 g·l-1, P < 0.001). A highly significant positive correlation (r = 0.8686; P < 0.001) was found between fraction A and B of β-lactoglobulin in sheep’s milk, whereas in cow’s milk there was a negative correlation (r = -0.3010; P = 0.0296). This study summarizes actual information of the whey protein content in different types of milk which may be relevant in assessing their allergenic potential.

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