The Portland daily press., 1875-01-18
THE FARM AND HOUSEHOLD.

How Hea ing assists the Rising of Cream.
Milk while hot, or over warm, is thinner
than when cold or cool, and offers less OBJ
structon to the upward passage of the
cream.
Second: a higher temperature expands
butter globues, which compose the cream,
twice as much as it does the rest of the milk,
thus causing the cream to rise more rapidly
the higher the temperature.
There is difference in the size OF the glob-
ules in all milk, and the small ones are
heavier in proportion to bulk than the larger
ones, consequently do not trise so rapidly.
When the milk is cold, there is so little diff
ference between the specific gravity OF the
small butter globules aud the rest of the milk,
that they rise very slowly and the milk is
likely to sour before they reach the surface !;
whilst if it were heated they would rise read
ily. Heating, therefore, facilitates the rising
OF the cream as well as prolongs its keeping
sweet; and for some reason which shall not
attempt to explain, makes the cream churn
easier than it would from the same milk I'M
scalded. Whether the yield would be greater
or less than from milk not heated that was
perfectly sound and could be set just as de-
sired. I do not know. But when milk be-
comes faulty from any of the reasons above
named, the yield is increased by heating, and
this is especially true when the temperature
of the milk room cannot be controlled.
The flavor of butter depends substantially
upon the mingled favOrs of its cheesy matter
and the olein or soft part of its fatty matter.
The olein is the most prominent and most
desirable element in the taste OF good but
ter.
The essential oils of some of the finer grasses
added to the oein, heighten its flavor and
give 10 butter the delicious aroma and fra
GRANGE that are so much priced by epicures.
Heating milk to 100 or 140 degrees does not
affect the olein and hence does not disturb
the substantial flavor of butter; but the heat
that drives off the iavors derived from various
taints and the essential oils of Objectionable
herbage also dissipates the more desirable
flavoring from the grasses which are in like
manner derived from essential oils. Hence
the heating process, which improves the
quality of butter from milk which is al all i'm
perfect, lowers the flavor of that from perfect
milk.
1t is notorious that highly favored butter
does not keep well. The reason is easily eX-
planned. Next to sugar, the organic germs
which constitute the ferment in milk and but
ter. and which work their early destruction,
feed most voraciously upon the light oils they
coptan. The more volatile the oils the more
RAPIDLY do the ferments consume them, and
the sooner are the goods in which they flour
ish destroyed. The dairyman who desires to
keep his butter long, works the davorlng oils
out of his butter by souring his milk. The
organic germs which constitute the terment
that produces the souring, live upon the oils
and, SO to speak, rot them and free the but
ter from their presence. These disposed of,
the more solid fats only are left, and there is
less in them to invite or stimulate change
hence the increased inclination to keep The
dairyman may not have been aware of the
nature of his work, but this is what he does
to make his butter keep. As already ex-
planned, heating milk volatilizes and dissi'
bates the favoring oils, driving off just what
the sour milk ate. 1t works the same result
by shorter cut and does it more effectually,
and promotes the keeping Of the resulting
butter more effectually than souring.-L. B.
a.