Composition of poorly and non-coagulating bovine milk and effect of calcium addition

2010 ◽  
Vol 77 (4) ◽  
pp. 398-403 ◽  
Author(s):  
Elin Hallén ◽  
Anne Lundén ◽  
Anna-Maria Tyrisevä ◽  
Maria Westerlind ◽  
Anders Andrén
Keyword(s):  
Bovine Milk ◽  
Protein Composition ◽  
Calcium Content ◽  
Casein Micelle ◽  
Independent Data ◽  
Coagulation Time ◽  
Data Set ◽  
Milk Samples ◽  
Micelle Size ◽  
Similar Association

Ninety-nine individual milk samples from 37 cows in lactation week 10–35, selected for producing well or poorly/non-coagulating milk, were compared regarding protein composition, total calcium content, casein micelle size, pH, and coagulating properties after addition of 0·05% CaCl2. The results showed that a low κ-casein concentration in milk was a risk factor for non-coagulation. CaCl2 addition improved coagulating properties (coagulation time, curd firmness) of nearly all samples and eliminated differences between poorly/non-coagulating and well-coagulating milk, particularly regarding curd firmness. A second, independent data set with 18 non-coagulating or well-coagulating milk samples were analysed for protein composition, where indications of a similar association with κ-casein was observed.

High pressure homogenisation of raw whole bovine milk (a) effects on fat globule size and other properties

2003 ◽  
Vol 70 (3) ◽  
pp. 297-305 ◽  
Author(s):  
Maurice G Hayes ◽  
Alan L Kelly
Keyword(s):  
High Pressure ◽  
Bovine Milk ◽  
Published Data ◽  
Inlet Temperature ◽  
Casein Micelle ◽  
Two Stage ◽  
Milk Samples ◽  
Globule Size ◽  
Pharmaceutical Industries ◽  
Fat Globule

Although widely adopted by the chemical and pharmaceutical industries in recent years, little published data is available regarding possible applications of high pressure homogenisation for dairy products. The objective of this work was to compare the effects of conventional (18 MPa, two-stage) and single or two-stage high pressure homogenisation (HPH) at 50–200 MPa on some properties of raw whole bovine milk (∼4% fat). Fat globule size decreased as HPH pressure increased and, under certain conditions of temperature and pressure, HPH yielded significantly smaller fat globules than conventional homogenisation. Fat globule size was also affected by milk inlet temperature. The pH of all homogenised milk samples decreased during 24 h refrigerated storage. Total bacterial counts of milk were decreased significantly (P<0·05) for milk samples HPH-treated at 150 or 200 MPa. Whiteness and rennet coagulation properties of milk were unaffected or enhanced, respectively, as homogenisation pressure was increased. Average casein micelle size decreased slightly when skim milk was homogenised at 200 MPa. Thus, HPH treatment has several, potentially significant, effects on milk properties.

Effect of the A and B variants of both αs1- and κ-casein on bovine casein micelle solvation and κ-casein content

1993 ◽  
Vol 60 (4) ◽  
pp. 505-516 ◽  
Author(s):  
Skelte G. Anema ◽  
Lawrence K. Creamer
Keyword(s):  
Genetic Variants ◽  
The Other ◽  
Casein Micelle ◽  
Lactation Period ◽  
Chromosomal Dna ◽  
Electrophoretic Method ◽  
Milk Samples ◽  
Micelle Size ◽  
Centrifugation Technique ◽  
Β Lactoglobulin

SummaryCasein micelle solvation, a micelle characteristic that is sensitive to many factors, has been measured by a centrifugation technique at 30 °C for a series of uncooled fresh skim milks at pH 6·3, 6·6, 6·9 and 7·1. The relative αs-(αs1- plus αs2-), β– and κ-casein contents of all centrifuge pellets and supernatants were determined by a standardized electrophoretic method. The calcium and phosphate contents of a number of the pellets and milk samples were also determined. Solvation of micelles from milks with various genetic variants of β-lactoglobulin (A and B), αs1-casein (A and B) and κ-casein (A and B) was often found to be lower for milks containing either the B variant of αs1-casein or the A variant of κ-casein. It was also found that these two variant caseins were associated with a lower κ-casein content of the milks and the micelles, which is consistent with the lower solvation as κ-casein is associated with smaller micelle size and greater solvation. The solvations also seemed to increase during the lactation period. It is possible that some of the other features of milk and its products that have been ascribed to the differences in functional character between the A and B variants of αs1-casein may be partly caused by the increased level of κ-casein. The reason for the association of the A variant of αs1-casein with higher concentrations of κ-casein (and micelle solvation) is not obvious but possibly the haplotype αs1-casein A, β-casein A1, κ-casein A contains a controlling sequence in the chromosomal DNA that enhances expression of the κ-casein gene.

High pressure treatment of bovine milk: effects on casein micelles and whey proteins

2004 ◽  
Vol 71 (1) ◽  
pp. 97-106 ◽  
Author(s):  
Thom Huppertz ◽  
Patrick F Fox ◽  
Alan L Kelly
Keyword(s):  
High Pressure ◽  
Treatment Time ◽  
Whey Proteins ◽  
Bovine Milk ◽  
Casein Micelle ◽  
Pressure Treatment ◽  
Casein Micelles ◽  
High Pressure Treatment ◽  
Micelle Size ◽  
Β Lactoglobulin

Effects of high pressure (HP) on average casein micelle size and denaturation of α-lactalbumin (α-la) and β-lactoglobulin (β-lg) in raw skim bovine milk were studied over a range of conditions. Micelle size was not influenced by treatment at pressures <200 MPa, but treatment at 250 MPa increased micelle size by ∼25%, while treatment at [ges ]300 MPa irreversibly reduced it to ∼50% of that in untreated milk. The increase in micelle size after treatment at 250 MPa was greater with increasing treatment time and temperature and milk pH. Treatment times [ges ]2 min at 400 MPa resulted in similar levels of micelle disruption, but increasing milk pH to 7·0 partially stabilised micelles against HP-induced disruption. Denaturation of α-la did not occur [les ]400 MPa, whereas β-lg was denatured at pressures >100 MPa. Denaturation of α-la and β-lg increased with increasing pressure, treatment time and temperature and milk pH. The majority of denatured β-lg was apparently associated with casein micelles. These effects of HP on casein micelles and whey proteins in milk may have significant implications for properties of products made from HP-treated milk.

Effects of high pressure on some constituents and properties of buffalo milk

2005 ◽  
Vol 72 (2) ◽  
pp. 226-233 ◽  
Author(s):  
Thom Huppertz ◽  
Mathias R Zobrist ◽  
Therese Uniacke ◽  
Vivekk Upadhyat ◽  
Patrick F Fox ◽  
...  
Keyword(s):  
High Pressure ◽  
Buffalo Milk ◽  
Casein Micelle ◽  
Coagulation Time ◽  
Casein Micelles ◽  
Rennet Coagulation ◽  
Micelle Size ◽  
Significant Difference ◽  
Β Lactoglobulin

In this study, effects of high pressure (HP) on some constituents and properties of buffalo milk were examined. HP treatment at 100–600 MPa for 30 min affected casein micelle size only slightly, whereas treatment at 800 MPa increased it by ~35%. Levels of non-micellar αs1- and β-caseins were increased by treatment [ges ]250 MPa, and were highest after treatment at 400–800 MPa. The level of non-micellar calcium increased with increasing pressure up to 600 MPa. The L*-value of the milk decreased gradually with increasing pressure, from ~82 for untreated milk to ~65 for milk treated at 800 MPa. Milk pH was increased by ~0·07 units after treatment at 100–800 MPa, with no significant difference between treatment pressures. Denaturation of α-lactalbumin occurred at pressures [ges ]400 MPa, and reached >90% after treatment at 800 MPa, whereas β-lactoglobulin (β-lg) was denatured >100 MPa, reaching ~100% after treatment at 400 MPa; after treatment [ges ]400 MPa, all β-lg was associated with the casein micelles. The rennet coagulation time of buffalo milk increased with increasing pressure, whereas the strength of the coagulum formed decreased after treatment at 250–800 MPa. Overall, HP treatment affected many constituents and properties of buffalo milk; some of these effects have also been observed in the milk from other species, but the extent of the effects, and the pressure at which they occurred, differed considerably.

scholarly journals Effects of composite casein and β-lactoglobulin genotypes on renneting properties and composition of bovine milk by assuming an animal model

1997 ◽  
Vol 6 (4) ◽  
pp. 283-294 ◽  
Author(s):  
Tiina Ikonen ◽  
Matti Ojala ◽  
Eeva-Liisa Syväoja
Keyword(s):  
Animal Model ◽  
Environmental Effects ◽  
Fixed Effects ◽  
Bovine Milk ◽  
Protein Composition ◽  
Favourable Effect ◽  
Milk Samples ◽  
Lactation Stage ◽  
Β Lactoglobulin ◽  
Friesian Cows

The effects of κ-β-casein genotypes and β-lactoglobulin genotypes on the renneting properties and composition of milk were estimated for 174 and 155 milk samples of 59 Finnish Ayrshire and 55 Finnish Friesian cows, respectively. As well as the random additive genetic and permanent environmental effects of a cow, the model included the fixed effects for parity, lactation stage, season, κ-β-casein genotypes and κ-lactoglobulin genotypes. Favourable renneting properties were associated with κ-β-casein genotypes ABA1A2, ABA1A1 and AAA1A2 in the Finnish Ayrshire, and with ABA2B, AAA1A3, AAA2A3, ABA1A2 and ABA2A2 in the Finnish Friesian. The favourable effect of these genotypes on curd firming time and on firmness of the curd was partly due to their association with a high κ-casein concentration in the milk. The effect of the κ-casein E allele on renneting properties was unfavourable compared with that of the κ-casein B allele, and possibly with that of the A allele. The β-lactoglobulin genotypes had no effect on renneting properties but they had a clear effect on the protein composition of milk. The β-lactoglobulin AA genotype was associated with a high whey protein % and β-lactoglobulin concentration and the BB genotype with a high casein % and casein number.

Interactive effects of casein micelle size and calcium and citrate content on rennet‐induced coagulation in bovine milk

2019 ◽  
Vol 50 (6) ◽  
pp. 508-519 ◽  
Author(s):  
Hasitha Priyashantha ◽  
Åse Lundh ◽  
Annika Höjer ◽  
Mårten Hetta ◽  
Monika Johansson ◽  
...  
Keyword(s):  
Bovine Milk ◽  
Interactive Effects ◽  
Casein Micelle ◽  
Micelle Size

Relationship between casein micelle size, protein composition and stability of UHT milk

2021 ◽  
Vol 112 ◽  
pp. 104856
Author(s):  
Marije Akkerman ◽  
Lene Buhelt Johansen ◽  
Valentin Rauh ◽  
John Sørensen ◽  
Lotte Bach Larsen ◽  
...  
Keyword(s):  
Protein Composition ◽  
Casein Micelle ◽  
Uht Milk ◽  
Micelle Size

scholarly journals Genetic polymorphism of kappa casein and casein micelle size in the Bulgarian Rhodopean cattle breed

2014 ◽  
Vol 30 (4) ◽  
pp. 561-570 ◽  
Author(s):  
P. Hristov ◽  
B. Neov ◽  
H. Sbirkova ◽  
D. Teofanova ◽  
G. Radoslavov ◽  
...  
Keyword(s):  
Genetic Polymorphism ◽  
Light Scattering ◽  
Cattle Breed ◽  
Cow Milk ◽  
Casein Micelle ◽  
Technological Properties ◽  
Casein Micelles ◽  
Milk Samples ◽  
Micelle Size

The present study aimed to compare the size of casein micelle in cow milk sample in function of kappa casein (CSN3) genetic polymorphism. Sixteen cows from Bulgarian Rhodopean cattle breed were genotyped by PCRRFLP analysis. Milk samples from the three found CSN3 genotypes (AB, AA and BB) were employed for the determination of casein micelles size by Dynamic Light Scattering (DLS). The results showed differences in the size and polydispersity of the casein micelles between the milks of cows with different genotypes. Hydrodynamic radii of micelles at a scattering angle of 90?C varied from 80 to 120 nm and polydispersity varied from 0.15 to 0.37. In conclusion casein micelle size of CSN3 AA cows (~ 120 nm) exceed with about 60% cows with (~ 80 nm) and BB genotype (~ 70 nm). These results could be useful for improving technological properties of the milk.

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