The Middlebury register. [volume] (Middlebury, Vt.) 1850-1882, 1875-11-30
Quality Of Milk.

THE Winthrop (Maine) cheese fac
tory, during q season of eighty-three
days, averaged only s.07 pounds of
milk to a pound of cheese. The milk
was chiefly that of Jersey and grade
Jersey cows. The cheese was also of
high quality. We have heard of no
other factory that averaged much less
than ten pounds of milk to pound of
cheese. The three best cows whose
milk went to this factory were pure
Jerseys, and yielded from thirty-five
milk per day. 1t has been generally
supposed that Jerseys were useless for
the cheese dairy, but this success will
doubtless encourage other tests. "-[Ex-
change.
We alluded, recently, 10 our expert
ments and Investigations made num-
Der of years ago, in relation to the quail
ity of milk. Among the more surpris-
ing results attained was the discovery
that the specific gravity Of milk does
not vary with its quality that is. the
milk of different cows may be of very
nearly the same specific gravity, and
yet differ greatly in richness. 1t is
this fact the discovery of which was
the result of frequently repeated and
varied tests that explains why the
specific gravity instrument Is SO useful
in determining water adulteration of
milk. The editor Of the Boston Guilt
vator, who is always, and very rightly
too, demanding that the test of actual
experiment should be applied to agri-
cultural theories, has disputed our con-
illusions on this point, though they
were reached by experiments that ut
terly changed our own preconcsived
opinion, based, like his own stiff1y
maintained views, on theory alone.
How is the singular fact in reference
to milk, noted above, to be explained
and reconciled with the equally we'll
msr and Mr.. Wetherell's present theo-
ry is based? That prior fact is, that
cream is lighter than the watery con-
stitusnt of milk, and that an increase
of cream, in milk will, therefore, re-
duoe its specific gravity, The infer
snoe that has been drawn from this
fact, and upon which Mr.. Wethersll
pins his faith, is that milk rich in
cream will show less specific gravity
on that account. But the truth, as
shown by actual and repeated test, is
different. Milk rich in cream does not
usually show less specific gravity
than milk poor in cream. Where
there Is variation, it is quite as likely
to show greater specific gravity. The
milk of our own Jersey COW has usual
ly "a specific gravity of one thousand
and thirty-two, though she makes over
an ounce of butter to q pound Of milk.
N. T. Sheafe, Esq, of Derby Line, VT,
for many years breeder of Jerseys,
kSsfsd '(eits had shown that quart OF
Jersey milk Is heavier than o quart of
common milk. He is very accurate
man, and has tried the experiment re-
peatedly, because he, as well as Mr..
Wetherell and ourself, expected a diff.
ferent result, on account Of the pres
enos of so much cream in the milk.
How IL this curious phenomenon ex-
planned? Real facts are not oontradic-
tory, though they may seem 90. Tho
discovery Of tertium quid, as our
scholastic brother editor would say-a
third fact-sets these two apparently
inconsistent facts in perfect harmony.
This tertium quid Is the fact that the
cssein and sugar in milk increase pari
passu more Latin, brother Wether-
ELI, increase, we should say, equally
with tue cream. When the milk of a
cow 10 rich, il is rich In case in and sugar
as well as In butter. When the milk
OF COW increases ia richness there Is
an addition of casein and sugar, as well
as of butter. Now the casein and SUI
gar in the milk are heavier than the
water, just as the butter Is lighter than
the water; so that these heavier con-
stltutents increase the specific gravity
as much Is the cream lessons lt-some-
times little more, which accounts for
Mr.. Sheafe's discovery.
The extract at the head of this arti-
Gle is entirely eonlrmatory of this
view, showing as 1t does that Jersey
milk will not only make more butter,
but more cheese, in proportion to its
bulk, than common milk. That is.
Jersey milk is richer every way, than
the milk of other breeds.
In regard to the specific gravity test
OF milk, We wish to note that the want
of q little knowledge often leads per-
sons who try experiments into serious
errors. In testing milk by its specific
gravity. no accurate results can be OBJ
tanned, unless all the samples are tested
at the same temperature. A variation
offs few degrees of temperature In the
different samples will entirely vitiate
the test, But when this simple point
Is observed, We never yet, in many
hundred experiments, have found the
specific gravity of milk from healthy
cows mot fed on dlstillery or brewery
slop) to vary as much as three degrees
of the hydrometer. When the milk OF
whole dairy has been poured togeth
er, we have never been able to note q
variation so great as two degrees.
But too much must not be claimed
for the hydrometer. 1t does not give
In ITSELF conclusive evidence Of the
adulteration of milk with water. But