The Olneyville times. (Olneyville [Providence, R.I.]) 1887-1917, 1916-02-11
APPROVES MILK
PASTEUR|zAT|0N
Makes Still Safer Most Care.
fully Inspected Product
SAYS GOVERNMENT PAPER
Scientists Give Results of Study
Eighty Percent Of Milk Delivered
in the Larger Cities is
Pasteurized.

objection TO pasteurization when
properly performed, and that the pro-
cess makes safer even the most care
fully handled and inspected milk, is
the conclusion of new professional
paper OF the Department OF Agricul-
ture, in which are set forth the most
recent conclusions of scientists in re-
gard to this matter.
II seems probable, says this paper,
that within the next two years
large proportion OF the milk supply
In the large cities will be pasteurized.
There is already marked tendency
I'm this direction. About 10 years ago
only percent Of the milk supply or
New York city was pasteurized. In
1914, S8 percent was treated in this
way. At the present time 80 percent
of the milk supply OF Boston is pas
teurized and there are correspond
Ing increases in many of the smaller
cities.
Before the value of pasteurization
rs a hygienic measure was as well
recognized as IL is today IL was prac-
ticed in secret by a number of the
milk dealers as a means of preserving
milk and preventing il from souring.
It's commercial value in this respect
Is undoubtedly great, but its chief
function is the destruction OF disease
producing organisms. Proper pas
teuriZation should destroy about 90
percent of all the bacteria i'm the milk.
although when the bacterial count OF
the raw milk is low the reduction may
be somewhat smaller. The efficiency
OF the process, II is pointed out, can
not be based on the percentage, but
rather on the character of the bac-
terra destroyed.
The kinds of bacteria that remain
alive after pasteurization depend on
the temperature TO which the milk
is heated and the species of bacteria
which are i'm the raw milk. Three
processes of pasteuriZation, known
respectively as the fash process, the
holder process and pasteurization i'm
The bottle. are now practised in this
country. In the fash process the
milk is raised quickly to tempera-
ture of about 100 degrees Fahrenheit
Dr more held there for from 80 sec
Dnds to minute. and then cooled
quickly. In the holder process the
milk is heated to n temperature OF
from 140 degrees to $50 degrees
Fahrenheit and held there for half
an hour When pasteurization in bot
Ties is practised the raw milk is put
into bottle with water tight seal caps.
which are immersed. in hot water and
held for from 20 to 80 minutes at a
temperature of las degrees +
), In general, ii may be said that the
holder process is coming into greater
favor than either of the others. This
process permits of the use of lower
temperatures, which, for various rea-
sons, is highly desirable. Another
method of pasteurization or, rather, u
modification of the present holder
process, suggested by the department
investigators. is that of bottling hot
pasteurized milk. The process CON
sists in pasteurizing milk by the
holder process at 145 degrees f. for
80 minutes. then bottling il while hot
i'm hot bottles steamed for 30 minutes
Immediately after filing. After fill
ing the bottles are capped, and may
be cooled by any of the systems in
which the caps are protected. The
bottles are sprayed with water or
cooled by forced air circulation.
When milk is held at 145 degrees f.
for 80 minutes. all the disease -produ-
cling bacteria, so far as can be ascer-
tanned, are completely destroyed. Al
the same time a larger percentage OF
the bacteria that cause milk to sour
and a smaller percentage of those
that cause il TO rot are left than when
higher temperature is employed. Pas
teurized at low temperature. milk
undergoes no change which affects its
nutritive value or its digestibiiity.
Subsection to temperature of $50
degrees F., or more, however, does
result in certain chemical changes.
Finally, pasteurization at low temper
atures is more economical because
the expense of heating and cooling is
less.
This, of course, does not mean that
insufficient pasteurization should ever
he tolerated. AS a matter of fact,
the process of pasteurization is fire.
quently performed improperly. For
the holder process l40 degrees Fab
renheit is the point at which investi-
cations have shown that disease
producing bacteria are killed, but In
practice II is advisable to use q tenn
perature several degrees above this
minimum Of safety. When the fash
process is used investigation has
shown that very many dealers fail
TO heat the milk TO a sufficiently high
temperature. This appears to be an
other argument for the use Of the
holder process, although conditions in
this respect are said TO have been
improved greatly in recent years.
Another common defect in the pro-
cess of pasteurization is carelessness
in the handling of the milk after II
has been treated. AS has been said
already, this is one reason why pas
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