Milk serum

Metges, C, Kempe K. and Schmidt, H.-L. 1990 Dependence of the carbon-isotope contents of breath carbon dioxide, milk, serum and rumen fermentation products on the 8 Cvalue of food in dairy cows. British Journal ofNutritim 63 187-196. 

The primary application of the procedure is the determination of the presence or absence of 3-lactam 7) residues in milk and secondarily to measure the levels quantitatively. The receptor assay system has now been expanded to qualitatively detect residues of tetracycline, erythromycin, streptomycin, chloramphenicol, novobiocin, and sulfamethazine in milk, serum and urine (Table II) (30). 

Our investigation was aimed at the development of the instrumental method for the diagnostics of BL with the help of the immune SPR-based biosensor which is able to determine viral specific Ab in the blood and milk serum. Such a biosensor should provide (1) direct analysis without any additional reagents (2) obtaining results within 3-5 min (3) use of miUc samples instead of blood and (4) low cost analysis (less than ELISA). 

The blood and milk serum from Poltava and Lugansk regions of Ukraine were supplied by Leiconad . Serum dilutions from 1 50 to 1 20000 were prepared in PBS (pH 7.4). The blood serum of the immunized animals was obtained from 6 to 12 months old calves after their vaccination with the medication developed by Leiconad . To prepare milk serum the fresh sample was acidified with 5% acetic acid and then centrifuged for 15 min at 400 g. 

The detection of viral specific Ab in milk serum is very important since the use of milk serum for the analysis rather than blood avoids physical injuries to the animals and extends the potential of the analytical method. We examined 15 samples of milk from RID-positive cows in the blood serum of which the titer of the viral specific Ab was 1 64—1 256. Simultaneously 10 samples of the milk from RID-negative cows... 

Fig. 8.3 The resonance angle of the immune biosensor in the analysis of the blood and milk serum. 1,2- blood serum, dilution 1 500, from RID-positive and RlD-negative cows, respectively 3,4 - milk serum, dilution 1 20, from RID-positive and RlD-negative cows, respectively...

Damianou, K., Kiosseoglou, V. (2006). Stability of emulsions containing a whey protein concentrate obtained from milk serum through carboxymethylcellulose complexation. Food Hydrocolloids, 20, 793-799. 

Ca-ion electrode. Ca2 + activity (rather than concentration) can be determined rapidly and accurately using a Ca2 + ion-specific electrode. Care must be exercised to ensure that the potentiometer is properly standardized using solutions that simulate the composition of milk serum. The Ca2 + activity is lower than the Ca2 + concentration - values of about 2 mM have been reported. 

Milk serum is supersaturated with calcium phosphate, the excess being present in the colloidal phase, as described above. The balance between the colloidal and soluble phases may be upset by various factors, including changes in temperature, dilution or concentration, addition of acid, alkali or salts. The solubility product for secondary calcium phosphate, [Ca2+][HPOr] is about 1.5 x 1(T5 or pKs = 4.85. 

Riboflavin (vitamin B2 6.18) consists of an isoalloxazine ring linked to an alcohol derived from ribose. The ribose side chain of riboflavin can be modified by the formation of a phosphoester (forming flavin mononucleotide, FMN, 6.19). FMN can be joined to adenine monophosphate to form flavin adenine dinucleotide (FAD, 6.20). FMN and FAD act as co-enzymes by accepting or donating two hydrogen atoms and thus are involved in redox reactions. Flavoprotein enzymes are involved in many metabolic pathways. Riboflavin is a yellow-green fluorescent compound and, in addition to its role as a vitamin, it is responsible for the colour of milk serum (Chapter 11). 

Reported values for the interfacial tension between milk and air vary from 40 to 60 Nm-1, with an average of about 52 Nm-1 at 20°C (Singh, McCarthy and Lucey, 1997). At 20-40°C, the interfacial tension between milk serum and air is about 48Nm-1 while that between sweet cream, buttermilk and air is about 40Nm-1 (Walstra and Jenness, 1984). Surface tension values for rennet whey, skim milk and 25% fat cream are reported to be 51-52, 52-52.5 and 42-45Nm-1, respectively (Jenness and Patton, 1959). 

Davies, D. T. 1974. The quantitative partition of the albumin fraction of milk serum proteins by gel chromatography. J. Dairy Res. 41, 217-228. 

Colostral Lipase. Driessen (1976) identified a lipase in bovine colostrum which is stable at pH 4.6, is bound to casein micelles, but is situated in the milk serum. Binding to heparin-Sepharose was weak, and... 

Hobman, P. G. 1984. Review of processes and products for utilization of lactose in depro-teinated milk serum. J. Dairy Sci. 67, 2630-2653. 

Menefee, S. G. and Overman, 0. R. 1939. The relation of the refractive index of evaporated and condensed milk serum to the total solids content. J. Dairy Sci. 22, 831-840. 

Munchberg, F. and Narbutas, J. 1937. Contribution to the refractometric investigation of protein-free milk serum. Milchwiss. Forsch. 19, 114-121. 

Porter, R. M. 1965. Fluorometric determination of protein in whole milk, skim milk and milk serum. J. Dairy Sci. 48, 99-100. 

Phospholipids are found in the milk lipid globule membrane and in milk serum in the latter, they appear to be primarily, if not exclusively, associated with a membrane fraction which sediments when milk is centrifuged at high speeds (the nature of this membrane material will... 

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