Fat content of milks

Fat Content of Milk. Raw milk as well as many dairy products are routinely analyzed for their fat content. The Babcock test, or one of its modifications, has been a standard direct measure for many years and is being replaced by indirect means, particularly for production operations. The Babcock test employs a bottle with an extended and caHbrated neck, milk plus sulfuric acid [7664-93-9] to digest the protein, and a centrifuge to concentrate the fat into the caHbrated neck. The percentage of fat in the milk is read direcflv from the neck of the bottle with a divider or caHper, rea ding to... 

One of the first attempts to use a biological RM was for the analysis of the fat content of milk. This was carried out in London in the late i88o s by a number of analytical chemists who were trying to identify adulterated milk. At that time milk was sold impackaged and at least 20 % of the miUc sold in London was adulterated by dilution with water. This work appears to be the first empirical round-robin approach for characterization of a RM. 

Table 3.1 The fat content of milks from various species (g 1 )...

The amount of fat in the ration has little effect on the fat content of milk, but the fatty acid composition of the dietary fat greatly influences that of milk fat (Chapter 4). Neither the total protein content of milk nor the proportions of the individual proteins is greatly influenced by the amount or kind of protein in the diet except at very greatly reduced intakes. Overfeeding with protein does, however, increase the NPN content of the milk (Thomas 1980). Milk of normal composition with the normal content and proportions of proteins can be produced on protein-free diets with urea and ammonium salts as the only sources of nitrogen (Virtanen 1966). 

Griffiths, T. W. and Featherstone, J. 1957. Variations in the solids-not-fat content of milk. Investigations into the nature of the solids-not-fat problems in the West Midlands. J. Dairy Res. 24, 201-209. 

Walstra, P. and Mulder, H. 1964. Gravimetric methods for the determination of the fat content of milk and milk products. V. Comparison of methods. Neth. Milk Dairy J. 18, 237-242. 

Table 1.16. Average fat content of milk from various species...

Van Vliet, T., Walstra, P. 1980. Relationship between viscosity and fat content of milk and... 

Nor Hayati, I., Aminah, A., Mamot, S., Nor Aini, I., Noor Lida, H.M., Sabariah, S. 2000. Melting characteristic and solid fat content of milk fat and palm stearin blends before and after enzymatic interesterification. J. Food Lipids. 7, 175-193. 

Numerous workers have investigated the effects of the fat content of milk on the composition of several cheese types, including Cheddar and Mozzarella (Gilles and Lawrence, 1985 Tunick et al., 1991, 1993a Bryant et al., 1995 Nauth and Ruffie, 1995 Drake et al., 1996b Fenelon and Guinee, 1999 Rudan et al, 1999). In studies where cheese making conditions are held constant, reduction of the fat content of cheese is paralleled by... 

Table 11.3. Effect of Fat Content of Milk on the Yield of Cheddar Cheese and Fat...

A high level of FFAs may cause minor errors in determination of the fat content of milk (e.g., a decrease of 0.01 0.03% fat per 1 meq/100 g increase in FFA), whether by older methods such as Rose-Gottlieb or turbidimetric or infrared methods (van Reusel, 1975 van de Voort et al., 1987). Lipolysis may also lead to false positives in testing for antibiotic residues in milk (Carlsson and Bjorck, 1992). 

Lawton, B.A., Pethig, R. 1993. Determining the fat content of milk and cream using AC conductivity measurements. Meas. Sci. Technol. 4, 38-41. 

Clarke, P.T., and Augustin, M.A. (2005). Manipulation of solvent-extractable fat content of milk powders. Lait 84,261-268. 

Table 16.11 Comparison of ruminal fermentation and fat content of milk produced from cows fed diets with varying chop length of the basal alfalfa silage...

Palm kernel meal generally refers to the product obtained after solvent extraction of palm oil from the oil palm, whereas palm kernel cake is produced by mechanical extraction. In practice, the term palm kernel meal is often used to describe either product. This food has a comparatively low content of protein, and the balance of amino acids is poor. The first limiting amino acid is lysine. The ratio of calcium to phosphorus is more favourable than in many other oilseed residues. The meal is dry and gritty, especially the solvent-extracted product, and is not readily eaten it is therefore used in mixtures with more acceptable foods. Attempts to use it mixed with molasses, as molassed palm kernel cake, have not been successful. It has a reputation for increasing the fat content of milk, and its chief use is for dairy cows. Palm kernel meal has been described as being balanced for milk production, but in fact it contains too high a proportion of protein to energy. 

De Vilder, J. and R. Bassuyt, Practical experiences with an InfraAlyzer 400 in determining the water, protein and fat content of milk powder, Milchwissenschaft, 38 65 (1983). 

This is a simple, rapid, accurate, and inexpensive test for determining the fat content of milk and cream, developed by Dr. S. M. Babcock of the University of Wisconsin in 1890. 

This is a test for determining the fat content of milk. In principle, it is very similar to the commonly used Babcock test. Sulfuric acid is mixed with milk, releasing the fat and leaving it free to rise. The Gerber bottle, in which this test is performed, has a thin graduated neck. Fat collects in the neck, where it is measured. 

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