The Lamar register., 1905-03-08
14fA4qK!211
Straininq Milk.


"Dairying," says:
Milk should be strained through a
fine strainer- By straining the milk
in room with fresh and pure air,
strong infection of bacteria is not
only avoided. but the advantage is
also gained that the milk is aired in
the best manner. The animal odor
of milk as drawn from the udder,
which is so unpleasant to many. Will
aot disappear TO any appreciable ex-
tent if the straining takes place In
the stable where the air is foul; the
odor may. on the contrary. often in
crease by the milk being kept there
Tor any length of time. In the fresh
air of the milk room the animal odor
would. however. largely disappear.
The straining of the milk may
cause germs of infection to he spread
in the milk instead of removing them
from the. same. that is If the strainer
cloth is not changed often enough. or
III the wire strainer is not frequently
cleaned In such cases 1t will easily
happen that the finest dust-like i'm
.purities remaining on the strainer are
lpressed downward by, the milk run
ning through and that the bacteria
found on the larger impurities are
gwashed off. Actual trials have con-
,vinced me that this may happen and
largely contribute to the infection OF
the milk. I spread some coarse soil
strongly impregnated with bacteria
'on fine strainer cloth and poured
newly separated milk containing only
,b small number of bacteria over the
sBame. The bacteria in the milk were
previously studied and found to be
different from the characteristic forms
jim the layer OF soil. After tho strain
ing the milk showed an entirely diff
ferent appearance under the micro
scope than before 1t now teemed
with the same kinds of bacteria as
,4hosc found in the soil In sample
taken after the straining had con
tinued for some time their number
6had. however. greatly decreased. and
soon the strained milk contained the
Same kinds of bacteria as the un'
strained milk. which plainly showed
,Ithat the soil particles had lost their
s.high bacteria content By bacteria.
illogical analysis Of the layer of soil
fhis proved to be the case. as this
..nOw contained only very small num-
s,ber of baoteria. The strained milk
WAS therefore far richer iu-bacteria
than before the straining and the
excepting qualities of the milk were
.adecreased by khe. .straining process
sWe thus see that by carelessness in
.,straining germs of Infection may be
scattered in the milk. The large i'm
,puEities g arc, removed from the milk
in the straining. but the most danger
Gus compOnents of-these. the fermen
tation-starters themselves. are washed
iato the strained milk.
It Is therefore very important to
change the strainer cloth often during
the straining: or. II a metal straineI
is used. the operation should bt
changed occasionally by allowing
steam OF hot water to pass throu q
the strainer In the opposite direction
The more unclean the milk the NOR,
frequently the changing and cleaning
process should takeeplace.
In my straining experiments 1t wa.
also shown that the more violently
the milk dropped on. the strainer. the
more the strained milk was mixet
with fine soil-particles and COW hairs
The kind OF strainer used also played
an important part in regard to tht
quality of the milk strained. Milk o
the highest purity was not obtained
by straining the milk through goot
linen strainer cloth. or by applying {
fine wiregauze strainer. but by plac
ing tho linen cloth on the wire-gauz,
strainer and allowing the milk to pas.
through them both. - BY changing tn,
former as often as need be. the wash
ing down of bacteria from the filti
remaining on the strainer will be. lin
tied as much as possible.