The ranch. [volume] (Seattle, Wash.) 1902-1914, 1906-01-01

is we'll known no substance more read
lily takes on odors and flavors with
which it comes in contact than does
milk. 1t is also prompt to surrender
its odors and fiavors if the great puri-
flying medium, the oxygen of the air,
is permitted to come in contact with
it. For this reason, the aeration of
milk has come into general use and
undoubtedly fills an important place
in the purifying of milk. While this
favorable effect OF the removal of
odors and f1avors peculiar to milk is
a natural consequence of aeration,
there is little evidence to show that it
makes the milk keep any longer, or
that in any other way it is improved.
In many instances aerated milk is
without doubt exposed to bacteria
which are in the air through which it
is passed. Whenever this occurs, the
keeping qualities Of the milk have
been endangered rather than benefited.
Aeration is perhaps most commonly
practiced for the purpose of reducing
the temperature of the milk as rapidly
as possible and must not be supposed
to have other advantages than those
mentioned. One of the most extensive
studies that has ever been made on the
aeration of milk was by the well
known bacteriologist, Prof. Marshall,
of Michigan. One of the results which
he demonstrated was that aerat1on
does not change the terminating act
ion of milk, nor does it reduce to any
extent the number of bacteria found
in it. He found, further, that aera-
ton did remove very large per cent
of the carbon dioXide and carbonlc
acid gas from the milk. AS this gas is
used in cargonated drinks and is con-
sidered healthful when taken in limit
ed quantities into the stomach, it
will readily be seen that its removal
might be considered as detrimental
rather than beneficial to the milk. He
said further that "the presence of
carbon dioxide had tendency TO
check the growth of bacteria and thus
keep the milk from sOuring for great
er length of time" In other words the
aeration of milk has a tendency to
cause it to sour more quickly than
when not aerated. Notwithstanding
these results, it would appear that the
practice of aeration is desirable one
to follow because of the results first
mentioned.
The Separator.
The use of the separator has been
considered helpful in purifying ana
thereby preserving milk. Some years
ago this practice came into consider
able favor: but recently it has been
found that milk so handled, while per-
haps improved for immediate use, has
been forced to absorb such large
amount of air that the effect on its
keeping quality has been injurious. SO
far as the removal of filth and slime
and other undesirable substances from
the milk is concerned there is no bet
ter method than by running it through
the separator In fact, all that can be
accomplished by the aerat1on, ana
much more, can also be secured by the
use of the separator. The labor ana
trouble necessary to do this WORK
must. however, be taken into consider
alton.
Pasteurization.
PasteurizaU1on is a process when
takes it's name from the famous sclen-
fist, DR.. Pasteur, who originated the
method. Pasteurization is the heating
of milk to a temperature and for
length of time that will kill the ma
iority of germs present without giving
the milk a cooked taste. There are
additional methods of heating milk
and a number of machines have been
devised for the process. The objects
for this are two: One to help the keep
ing qualities of the milk, and the other
to kill the injurious germ which may
be present in the milk. AS is well
known, milk is medium in which dis
ease germs find a most congenial home
and it may be attributed to this fact
that they SO readily secure it. 1t Will
be readily seen that pasteurizat1on is