Staunton spectator and vindicator. [volume] (Staunton, Va.) 1896-1916, 1904-04-01
BACTERIA IN MILK.
Bugs Which Make Milk Turn Sour ar d
What Makes them Grow.

|
The Connecticut Agricultural Col.
leye and station has just published a
| bulletin which gives some importal t
facts about milk and cream, from
| numerous experiments on the college
fam. The following extracts from
the bulletin are we'll worth studying
by all who handle milk and cream: /:
Dairymen at the present time under
stand that milk is sure to contain bac-
terra in greater or less umbers, aud
that these bacteria are the cause Ct
the various changes characterizing the
spelling of milk. 1t is the type of
bacteria known as Tactic bacteria that
is responsible for the sOuring of milk
and all of the other changes which are
liable to prove troublesome to the
d airyman. Shiny milk. bitter milk. etc.,
are today well known to be due also
to bacteria in the milk. 1t is not SIM
ply the presence of the bacteria in the
milk that produces these changes, but
rather their growth and multiplication.
L they did not multiply at all the milk
would not sour; the more rapidly they
multiply, the quicker the changes of
the milk take place: the longer the
growth may be delayed and the slower
it is, the longer the milk may be retain
ed in its fresh condition. These facts
are fundamental phenomena associat-
ed with the keeping of milk, and ev-
cry milkman should therefore under
stand as foundation of dairy practice
that the keeping of milk is dependent
upon preventing or checking the multi
plication OF bacteria, rather than upen
simply preventing their presence in
milk.
A second fact which is not so thor
oughly appreciated, but is equally true.
is that the rapidity of growth of all
species of bacteria is dependent upon
temperature. At temperature Of
freezing bacteria do not grow at all,
an1 milk, therefore, if frozen, may be
kept indefinitely without any changes
taking place therein. If the milk is
kept at a few degrees above freezing
the growth of bacteria begins, but at
low temperatures this growth IS ex-
tremely slow. AS the temperature rises
the rapidity Of bacterial growth in
creases. When the temperature reach
es 10 degrees bacteria grow very rapid
ly; at temperature of so and 80 de-
grees they grow more rapidly still; and
at temperature of about 100 degrees
the growth of some species of bacteria
is most rapid of all. The temperature
of so degrees is to he emphatically re-
commended to the dairymen for the
purpose of keeping his milk sweet and
in proper condition for market, but be
must especially be on his guard against
the feeling that milk which is several
days old is proper for market, even
though it is still sweet and has not
curdled. Q Qlite the reverse is the case.
Olu ullh Is HtNcI WuOlcoUuC. cNou
though it has been kept at temper
ature of so degrees and still remains
sweet and uncurdled. This very con-
siderably modifies some of our previous |
ideas concerning milk, for it has been |
generally believed that so long as the |
milk remains sweet it is in good condi-
tion for use. Quite the contrary is
the case, if 1t has been kept at a tenn
perature of so degrees or in this vicin-
ity. 1t is not unlikely that it is this
fact that leads to some of the cases Of
ice cream poisoning SO common in
summar. The cream is kept at a low
temperature for several days until a
coDeiderat quutity h .saccumulated .s |
or demsnd has cume for tie cream,
and when made into ice cream 1t is |
filled with bacteria in great numbers |
and of suspicious character.-Spring- |
field Republican.