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Milk Composition & Synthesis
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Milk Composition
Density, Etc.

More properties of milk :

The density of milk (g/mL) changes with temperature.
For example, the denisty of milk = 1.003073 - 0.000179t - 0.000368F + 0.00374N,
where t = temperature in degrees C; F = percent fat; and N = percent nonfat solids

Question: If you collected milk from a Jersey cow (5.5% milk fat; 15% milk solids) and stored the sample at 4 C, how would the density of that milk compare with the density of milk from you collected from a Holstein cow (3.5% milk fat; 12.2% solids) and stored at 4 C? What if your milk samples were stored at room temperature (22 C)?

Specific gravity of whole cow milk (ratio of density of milk to density of water) varies among breeds and among cows within breed. For example, mean specific gravity of Holstein milk at 20 C/20 C is 1.0330 (range 1.0268 to 1.0385) and for Ayrshire milk is 1.0317 (range 1.0231 to 1.0357), while Jersey milk also has a mean of 1.0330 (range 1.0240 to 1.0369). [see Sherbon JW, Physical Properties of Milk, Chapter 8 in Wong et al, 1988]

Viscosity is measured in poise, defined as the force in dynes per square cm required to maintain a relative velocity of 1 cm/sec between two parallel planes 1 cm apart. At 20 C, whole milk is about 20 centipoise, skim milk about 1.5 centipoise, and whey about 1.2 centipoise. [see Sherbon JW, Physical Properties of Milk, Chapter 8 in Wong et al, 1988]

Milk Composition & Synthesis