Evening star. [volume] (Washington, D.C.) 1854-1972, 1930-10-12

At last he got it. and published it freely for
all the world As fast dairymen could get
the hang of it they began to use it. Milk water
ers and cream swimmers goth ethics
THOUSANDS turned honest overnight. while
the honest dairy farmers rejoiced in an
even break at last. Payment was by the pound
of butterfat now, and gallons of water or thin
milk meant merely much Improbable
hauling
Babcock's test is all the more remarkable not
merely for its very literal bread-and-butter i'm
portance, but also because it is such simple
thing when you see 1t made that you are
tempted to wonder why the scientists and agri-
cultural technologists of the world have been
heaping praises and prizes on Prof. Babcock's
careless head for half his lifetime. The answer
to that is the old story of Columbus and the egg
Somebody had to think of it first
All there is to the Babcock test is to put
samples of the milk to be tested into some long
necked bottles with marks at proper intervals
on their calibrated necks, pour in sulphuric acid
and whirl the bottles in centrifuge.
When the machine is slowed down, the millrt
Is in the bottles and the butterfat is up in their
necks; where the percentage can be read OF
directly by the grade marks. 1t sounds simple,
doesn't it?
But it is worth while to look at milk a little
more closely to see why through all the CEN
turtles of butter making nobody ever worked out
this test and why it was chemist at last, with
really very little knowledge about the practical
problems of commercial diaries, who thought of
dumping sulphuric acid into milk and then
whirling it around to make the cream rise"
Milk is not a single, simple, uniform sub
stance like water 1t looks as though it were
"all one piece when it comes out of the cow,
but everybody has seen thousands of times,
If milk is left to itself for little while it sepa-
rates itself into two parts One of these is
cream, the other is skim milk
If you churn the cream you again get sepa-
ration this time into a nearly pure fat-butter-
and the thickish buttermilk. But If you squeeze
the butter thin, watery stuff comes out; 20
butter has at least two substances in it.
And if you let the skim milk alone until sour
ing bacteria have done their work upon it, you
find that il "curdles'-separates into semi
solid, cheesy substance and a thin, watery fluid
called whey.
But to get real picture of how much butter
fat there is in a given lot of milk you should
be able to get the butterfat droplets-al of
them, even the tiniest-out of their films.
Prof. Babcock was given this problem 40 years
ago, and he solved it not by thinking especially
of milk but by going back to his general knowl-
edge of chemistry, which reminded him that an
proteins are soluble in sulphuric acid and that
fats are not.
Then, to hasten the process of separation he
put his milk and acid mixture in a centrifugal
machine and spun the mixture about. The
heavier milk and water vent to the bottom and
the fat hoated clear, where it could be measured
There is probably no modern invention that
has so radically reformed q great industry, and
it was the beginning Of the science of milk
chemistry which today yields you such diverse
products as dice, beauty creams and cigar wrap.
pers, all from the everyday cows milk which
the daiymaEf leaves 81 your door every naorninG