327 
No. Milk Water Muci.age Butter Time churned. 
oC, Ci. Cres per cent, minutes, 
1 400 4, a EC Aat 4.37 20 
2 350 50 ett) 4.54 20 
3 300 100 cae 4.45 20 
4 350 mei) 50 2.86 40 
5 300 yee, 100 0) 80 
6 300 YEby 100 2.6 80 
The mucilage and the water were added to the samples. 
when the milk was set. In numbers 5 and 6 containing 
100 c. c. of mucilage, the casein separated in a short time 
and rose to the surface as cream leaving the serum below 
clear. In number 6 this was drawn off just before churn- 
ing and replaced by an equal volume of water, thus greatly 
reducing its viscosity. Other tests of this kind were made 
with similar results. The addition of water, however, 
nearly always increased the time required for churning, 
owing, no doubt, to the proportion of fat being diminished. 
Several attempts have also been made to churn colostrum 
milk, the serum of which is extremely viscous, and in no 
case was any butter obtained although the per cent of fat 
was above the average for. milk. The analyses of two 
samples are given. 
I II 
Solids 27.00 27.29 
Fat 3.90 3.98 
Ash 74 es Wer 
Albuminoids 18.75 19.31 
Sugar Ni 8 oho Te i ao SN 
If we assume that the coefficient of viscosity for the al- 
buminoids in these samples was the same as in average milk 
the viscosity of the milk serum would have been 786 in No. 
1, and a little more in No. 2. 
When diluted with an equal volume of water and churn-: 
ed the result was the same as with the pure colostrum’ In 
this last case the per cent of solids was about the same as in: 
normal milk, but owing to the large proportion of albumen 
in solution, it was much more viscous. When three vol- 
umes of water were added afew granules of butter were: 
formed after prolonged churning, but it could not be gath- 
ered. The addition of more than three volumes of water 
gave no better results. It could hardly be expected that 
butter would be obtained from these milks after being so 
largely diluted, as the per cent of fat was not much larger 
than is found in average buttermilk. 
Another illustration of the influence of viscosity in re- 
tarding the action of the churn is furnished by the ordinary 
method of preparing whipped cream in which the forma- 
tion of butter is prevented by the addition of a little gela- 
tine to the cream. 
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