Milking procedure

To calculate the portion of administered radioactivity excreted with the milk, it is necessary to know the quantitative milk secretion of each particular rat. However, this is not possible within the present study due to the stress inflicted on the animals by the unusual milking procedure which led to milk retention. Assuming values known from literature (Bornschein (1977)) 6.5 ml per day the portion excreted with the milk can be estimated. 

Protein Content. The protein content of milk can be determined using a variety of methods including gasometric, Kjeldahl, titration, colorimetric, and optical procedures (see Proteins). Because most of the techniques are too cumbersome for routine use in a dairy plant, payment for milk has seldom been made on the basis of its protein content. Dye-binding tests have been appHed to milk for determination of its protein content these are relatively simple to perform and can be carried out in dairy plant laboratories. More emphasis will be given to assessing the nutritional value of milk, and the dependence on fat content as a basis for payment will most likely change. 

Membrane Sep r tion. The separation of components ofhquid milk products can be accompHshed with semipermeable membranes by either ultrafiltration (qv) or hyperfiltration, also called reverse osmosis (qv) (30). With ultrafiltration (UF) the membrane selectively prevents the passage of large molecules such as protein. In reverse osmosis (RO) different small, low molecular weight molecules are separated. Both procedures require that pressure be maintained and that the energy needed is a cost item. The materials from which the membranes are made are similar for both processes and include cellulose acetate, poly(vinyl chloride), poly(vinyHdene diduoride), nylon, and polyamide (see AFembrane technology). Membranes are commonly used for the concentration of whey and milk for cheesemaking (31). For example, membranes with 100 and 200 p.m are used to obtain a 4 1 reduction of skimmed milk. 

Yogurt is manufactured by procedures similar to buttermilk. Milk with a fat content of 1—5% and soHds-not-fat (SNF) content of 11—14% is heated to ca 82°C and held for 30 minutes. After homogenization the milk is cooled to 43—46°C and inoculated with 2% culture. The product is incubated at 43°C for three hours in a vat or in the final container. The yogurt is cooled and held at <4.4° C. The cooled product should have a titratable acidity of not less than 0.9% and a pH of 4.3—4.4. The titratable acidity is expressed in terms of percentage of lactic acid [598-82-3] which is deterrnined by the amount of 0.1 AiNaOH/100 mL required to neutralize the substance. Thus 10 mL of 0.1 AiNaOH represents 0.10% acidity. Yogurts with less than 2% fat are popular. Fmit-flavored yogurts are also common in which 30—50 g of fmit are placed in the carton before or with the yogurt. 

The isotope molybdenum-99 is produced in large quantity as the precursor to technetium-99y, a radionucleide used in numerous medical imaging procedures such as those of bone and the heart (see Medical imaging technology). The molybdenum-99 is either recovered from the fission of uranium or made from lighter Mo isotopes by neutron capture. Typically, a Mo-99 cow consists of MoO adsorbed on a lead-shielded alumina column. The TcO formed upon the decay of Mo-99 by P-decay, = 66 h, has less affinity for the column and is eluted or milked and either used directly or appropriately chemically derivatized for the particular diagnostic test (100). 

Pasteurization, the heating of certain fluids, frequentiy milk or dairy products (see Milk and milk products), destroys potentially harmful organisms such as mycobacteria, M. tuberculosis M. bovis or M. avium. Pasteurization, carried out at 62°C for 30 min or at 72°C for 15 s, is not a sterilization procedure. 

The development of analytical strategies for the regulatory control of dmg residues in food-producing animals has also been reviewed (128). Because of the complexity of biological matrices such as eggs (qv), milk, meat, and dmg feeds, weU-designed off-line or on-line sample treatment procedures are essential. 

FEASIBILITY TO APPLY THE PROCEDURE OF NONDESTRUCTIVE X-RAY FLUORESCENCE ANALYSIS OF PLANTS FOR MILK POWDER EXAMINATION... 

Variety of biochemical composition and physical features of milk, as well as compound forms of mineral components foreordain necessity to develop the analytical procedures, in which initial sample state suffers minimum change. Absence of dried milk reference standai ds (RSMs) is an obstacle to use nondestructive XRF for solving the given analytical task. In this communication results of nondestmctive x-ray fluorescence determination of Na, Mg, Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Rb, Sr, Zr in dried milk powders of limited mass (less than 2 g), obtained with using plant RSMs to calibrate, ai e discussed. 

De Goeij JJM, Kosta L, Byrne AR, and Kucera J 1983) Problems in current procedures for establishing recommended values of trace-element levels in biological reference materials, illustrated by IAEA Milk Powder A-ii. Anal Chim Acta 146 161-169. 

Iron is, as part of several proteins, such as hemoglobin, essential for vertebrates. The element is not available as ion but mostly as the protein ligands transferrin (transport), lactoferrin (milk), and ferritin (storage), and cytochromes (electron transport) (Alexander 1994). Toxicity due to excessive iron absorption caused by genetic abnormalities exists. For the determination of serum Fe a spectrophoto-metric reference procedure exists. Urine Fe can be determined by graphite furnace (GF)-AAS, and tissue iron by GF-AAS and SS-AAS (Alexander 1994 Herber 1994a). Total Iron Binding Capacity is determined by fuUy saturated transferrin with Fe(III), but is nowadays mostly replaced by immunochemical determination of transferrin and ferritin. 

The methods recommended above for mitigation of on-farm GHG emissions in the fluid milk supply chain were obtained from years of research that evaluated the impact of various practices on each GHG. The research was typically conducted on experimental farm plots under a particular farm management system meaning that the data are relevant for that system with a particular soil type, herd size, and climate, for example, and may not apply to a different farm management system. The impact of a particular mitigation procedure for one GHG on another is also relatively unknovm as well as the impact of the mitigation on more complex interactions such as the total C and N throughout the farm. 

Kulozik, U. (2007). Procedures for the manufacture of milk with an extended shelf-life. Current techniques and new options. Dtsch. Milchwirtschaft 58, 268-271. 

Following research by Tossavainen et al. (1986), extrusion is often used to produce insoluble acid casein from skim milk powder and to convert acid casein into sodium caseinate. The procedure is faster than batch mixing (Akdogan, 1999). 

Both multi-residue methods are presented in several parts, which separate general considerations from procedures for extraction, cleanup and determination/ confirmation. Whereas in EN 12393 several extraction and cleanup steps cannot be combined arbitrarily, the modular concept is utilized to a greater extent in EN 1528. In the latter standard, there is no limitation to the combination of several extraction procedures, mostly designed for different commodities, e.g., milk, butter, cheese, meat or fish, with different cleanup steps. Both standards, EN 1528 and EN 12393, do not specify fixed GC conditions for the determination and confirmation. All types of GC instruments and columns, temperature programs and detectors can be used, if suitable. 

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