Evening star. [volume] (Washington, D.C.) 1854-1972, 1904-02-15
BACTERIA IN MILK.
Bugs Which Make Milk Turn Sour and
What Makes Them Grow.

From the Springfield kePuDhe1h
The Connecticut Agricultural College and
station has just published a bulletin which
gives some important Facts about milk ana
cream, from numerous experiments on the
colIep,e farm. The following extracts from
the bulletin are well worth studying by all
who handle milk and cream: Dairymen at
the present time understand that milk Is
sure to contain bacteria in greater or less
numbers. and that these bacteria are the
cause of the various changes character
izine the spelling of milk. It 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 dairyman, Shiny
milk bitter milk, etc. are today well
known to be due also to bacteria In the
milk It Is not simply the presence of the
bacteria IN the milk that produces these
changes but rather their growth and null
tiplfcation If 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
NAV be DELAYED and the slower it Is, the
longer the milk may be retained in It's fresh
condition. These facts are fundamental
phenomena associated with the keeping of
milk, and every mtlkinan should therefore
understand as a founda ton of dairy prac-
tice that the Keeping OF milk is dependent
upon preventing or checking the multiplied
ton of bacteria, rather than upon simply
preventing their presence IN milk:
A second fact which IS not thoroughly
appreciated, but is equally true, is that the
rapidly of growth of all species of bae-
terra Is dependent upon temp erat1re. AT
temperature Of freezing bacteria do not
grow at all, and milk therefore, II frozen.
may be kept Iindafnitely without any
changes taking place therein. II the milk
Is kept at a few degrees above freezing the
growth Of bacteria begins, but at low tenn
per atures this growth. Is extremely slow.
As the Temperature rises, the rapidity Of
perature reaches 70 degrees bacteria grow
very rapidly; at a temperature of 80 and
90 degrees they grow more rapidly still;
and at q temperature OF about 100 degrees
the growth Of some species OF bacteria is
most rapid Of All The temperature OF 50
degrees is to be emphatfcaIIy recommended
to tha dairyman for ths purpose Of keeping
his milk sweet and In proper condition for
market. but he must especially be on his
guard AGAINST the feeling that milk which
is several days old = proper for nnarkst.
curdled. Quite the reverse fs the case. Old
milk ID never wholesome. even though II has
been kept at temp1faenre Of % degrees
and still remains sweet and uncnrdled.
This very considerably modines some Of our
been generally believed that 50 long as che
milk remains sweet IL is IN good condition
for use. Quite the contrary Is the case. IL
1t has been kept att Temperature Of 50 de-
grees or in this vicinity. 70 Is not unlikely
that II In this fact that leads to some. Of tina
cases of ice cream poisoning so common Ia
summer The cream Is kept at low tenn
perature for several days until a. consider
able quantity has accumulated or demand
has come for ice cream. and when made
into Ice cream It is filled with bacteria In
great numbers and of suspicious char
aoter.