|
Total Solids %
|
Fat (%)
|
Casein (%)
|
Whey Protein (%)
|
Lactose (%)
|
Ash (%)
|
|
| Ayrshire |
12.69
|
3.97
|
2.68
|
0.60
|
4.63
|
0.72
|
| Brown Swiss |
12.69
|
3.80
|
2.63
|
0.55
|
4.80
|
0.72
|
| Guernsey |
13.69
|
4.58
|
2.88
|
0.61
|
4.78
|
0.75
|
| Holstein |
11.91
|
3.56
|
2.49
|
0.53
|
4.61
|
0.73
|
| Jersey |
14.15
|
4.97
|
3.02
|
0.63
|
4.70
|
0.77
|
Sources:*Bascom Scott, "Jersey Calf Management", PhD Dissertation, Virginia
Polytechnic State Univ, 2002.
*Fox P. et al,
Fundamentals of Cheese Science Kluwer Academic, 2000 (Ch. 3).
Analysing Milk
How is the milk analysed? The classical and reference method for measuring
milk Protein is the Kjeldahl way. It is done in a Lab and very accurately measures
the amount of Nitrogen in the milk. To obtain the protein value, one assumes that
milk protein contains 15.67% Nitrogen, so that Nitrogen = 0.1567 * Protein.
The actual protein content in milk can then be determined from:
Protein = Nitrogen / 0.1567 or Protein = Nitrogen * 6.38.
However, the composition of milk protein (e.g
casein
and the whey proteins) can vary
from sample to sample, so in fact, the amount of Protein calculated
from the amount of Nitrogen is only an approximation.
Source: DePETERS E. J. and FERGUSON J. D,1992 J Dairy Sci, (1992) Vol 75, pp. 3192-3209.