Evening star., 1940-11-19
Of Stars, Men
And Atoms
Notebook Of Science Progress
b In Laboratory, Field
And Study
BIZ Thomas r. Henru.

By Thomas r. Henry.
A Department of Agriculture chemist
has just found a way Of making sugar
out Of sorghum-with yield approx
mately equal to that obtained from
sugar cane.
This is secret which has bafled SCI
ence for half a century. The economic
potentialities are enormous, although the
process as yet is far from commercially
practical. 1t may mean eventually sue
cessful production of crystalline sugar
as far north as the Dakotas and far into
the arid areas of the Great Plains, at
cost even below that at which sugar now
Is made from sugar cane. Department
Of Agriculture scientists warn, however,
that they are only standing at the
Threshold, that much may depend on
the varieties used, and that probably the
further south the crop is grown the bet
ter the sugar content.
Sorghum is grown extensively through
out the Midwest. Its chief use is in
silage for winter feeding of cattle and
for the familiar sorghum syrup. 1t is
oSoSAAcSu ~ viz DoPdi tiIlCllI VI hRll.
culture as "the camel of the plant
world" 1t is fairly resistant to cold and
will grow luxuriantly in areas far too
dry in most years for corn. The great
advantage over sugar cane is that sor-
ghum is grown from seed like any other
grain.
The problem of obtaining crystalline
from cnrohIr,, ipin o;,
as hopeless by Department of Agriculture
chemists so years ago, but there have
been great technical advances since then.
Less than two years ago Dr. E. K. Ven-
tire, chemist at the Mississippi experiment
station of the department, revived the
experimentation 1t long had been rec
ognized that there was plenty of sucrose,
the variety Of sugar obtained from sugar
cane, in sorghum, but it could not be
made to crystalline. Instead it always
came out as a sticky mass, impossible
for commercial use.
Dr. VentreS first experiments showed
that there were two other substances in
the juice which must be eliminated be-
fore there could be any hope of crystal
lzation-salts Of organic acids and
starehes which had just stopped short of
becoming sugars chemically, but which
were mixed with the sucrose in an ap-
parently hopeless tangle Moreover, he
found, the starches were at various stages
OF maturity, from chemical point of
view. and that they rapidly increased in
purity as the plant became ripper. Only
the fully mature starches were capable
of being separated from the sucrose, and
as long as much of the starchy sub
stances remained crystallization was
hopeless.
He finally accomplished the separation
in three steps. First the sorghum Juice
was mixed with lime and then heated to
the boiling point. About 70 per cent of
the starch was concentrated by this pro-
cess as scum on top of the syrup,
from which it could be scooped. Then
about II per cent more was removed bv
use OF the centrifuge. operating on the
principle OF the cream separator. For
the final step DR.. Ventre used bio-chem-
ical agents known as engines, especially
one obtained from matted barley.
From this point on the sorghum sugar
crystallized about as easily as does the
sucrose in sugar cane. 1t was described
by DR.. Ventre as of about the consist
ency Of wet sand" With sugar surpluses
a serious economic problem, the discov-
cry may threaten still further trouble
for the limited cane-growing areas OF
the United States, and to Cuba. Puerto
Rico and Hawaii. and Department of
Agriculture economists are puzzled over
the ultimate effects of sorghum sugar.
The crop can easily be increased many
fold, they say. Sorghum is a native of
Africa, but has spread over much of the
world. One species of it is broom corn,
long used for making brooms This par
ticular species, which has a very small
sugar content, was the first introduced
into the United States. Benjamin Frank
lin bought new broom, just imported
from France. He noted a few seeds left
on one Of the broom straws, and planted
them in his garden. The crop spread
rapidly.
About the middle of the last century
Horace Greeley became excited over the
possibilities Of sorghum sugar industry.
At his request an Englishman, Leonard
Wray. started the cultivation of some
improved varieties, brought from Africa
by devious route through China and
France, in South Carolina and Georgia.
The late Harvey W. Wiley of pure food
fame was leader in the early expert
ments to crystalline sorghum sugar, but
finally gave up in disgust, and until the
present discovery the crop seemed des-
tined to be minor farm crop in the
United States. Now more than 80 va
rieties of the plant are grown CONNER
cially in the United States and new ones
are appearing every few years.