Polynesian. [volume] (Honolulu [Oahu], Hawaii) 1844-1864, 1850-11-09
MELSEN'S METHOD OF EXTRACT.
ING SUGAR.
Translated from the French.)

|
The extraordinary circumstances in which
| am placed make it my duty TO draw from a
most extensive research few observations
tending to give an exact idea of the investi-
cations am pursuing.
Whatever may be the fate which awaits
the methods have endeavored to introduce
for the treatment Of saccharine substances
(matieres sucriees), am confident that all
the observations which are my own, will be
found correct, and that knowledge of them
will give rise to useful reflections on the part
of sugar manufacturers, and no doubt to new
practical applications, in the various opera
tions they have occasion to perform
| 1t is a we'll authenticated fact that in sound
Sugar Cane, as well as. in the sound Beet
root, there exists no other sugar but what is
cristaIlizable. 1t is we'll known too, that it
is easily extracted by means Of weak alcohol,
which dissolves it, and subsequently, upon
evaporation deposits it in the form Of pune
and colorless crystals.
In bitter almonds also there exists crys-
tallizable substance ''amygdaline" which can
he extracted by alchol, and remains crystal
lized and unchanged after the evaporation of
that medium. But this is no longer the case
when water is used instead of alcohol. The
amygdaline Of almonds disappears and be-
comes changed, and forms by a new ar
rangement of its elements numerous sub
stances entirely new and different. For wa
ter to produce this result, it is necessary TO
let it be in contact with the air, it must also
find and dissolve certain fermenting substanc-
es contained in the tissue of the almond, as
well as the amygdaline. In the sugar cane,
and in the beet these fermenting substances
also exist in sufficient quantities to moderate
the transformation Of the sugar into other
products For their action to be exterded il
is requisite that they be brought in contact
with the sugar, by the means of water, and
that they be exposed to the influence of the
air.
| Every one knows with what rapiditv the
sap Of the sugar cane changes in those hot
regions where it is grown, and although that
change goes on with less rapidity in the juice
! Of the beet root, it is enough so to have led
l TO endeavors to find methods to render its
manufacture more and more speedy, in order
to avoid this cause Of trouble and loss. For
chemist who is making an analysis, the
problem of the extraction Of sugar is resolv-
ed by the use Of alcohol; by that he separ-
ates the sugar from IFS matrices; he changes
the nature of the latter, without altering The
former and places the sugar beyond the
reach of destructive Influences. But if he is
going to undertake manufacturing opera
:ion, he must have recourse to cheaper
medium, and one easily managed. Now al
cohol is expensive and requires infinite pre-
cautions in its use if you wish to escape the
frightful risks of explosion or confagration
which attend it. The use of alcohol discard
ed, it is beyond the power Of chemistry to
discover liquid endowed with the essentia!
properties which characterize it in this case,
which like it will prevent any fermentation
from taking place even in contact with the
air? think not. am very far even from
believing that the process at which have
arrived, after so long cropping in the dark, is
the best, even though it should prove to be
the only one that can be used to advantage
The cells of the tissue or cane contain
sugar dissolved in water, and there. as is
well known the sugar keeps long time. Il
water could be used as a dissolvent without
destroying the conditions brought about al.
ready by nature, the sugar might he extract
ed unaltered. The difficulties which are me-
with there, do not belong to the sugar mol
the water, but rather to the air, and to the
fermenting substances which its contact de-
: velopes This point established, can canes
he crushed or beets rasped in vacuum: the
juice be extracted and transported to boiler:
either for detection or evaporation in con
tinued vaccuum? If this were practicable
on large scale, the problem might perhap.
be resolved. But when it is considered tina
an almost imperceptble breath Of air j:
: enough to create fermentation,it may at once
be perceived that it is impossible to put sucf
a system into practice. / have not attempt
= ed it. But it appeared more easy to arrive
at the result by operating in an inert gas
It such as the carbonic acid, by rasping ths
beets in the carbonic acid, and then washing
them in water charged with acid carbonate o
lime, or acid carbonate Of magnesia. My trials
did not succeed as well as they promised. 1h'
slightest traces Of air produced fermentation
and these various agents only replaced with
out annulIing them; their efficacy always
proved very doubtful.
will cite, merely by way Of note, class
of agents to which recourse is frequently hat
to prevent fermentation. These are the me
: talic oxides, capable of combining with fer
menting substances or matters which pro
: duce them, and forming insoluble COMPOUNDS
The oxide of mercury, and the oxide of lea
i are of this class. In ar analysis in the la
boratory, the subacetate of lead is easil
: used and with effect, for it precipitates al
s fermentisg substances, and all matters tha
h create them, and leaves the sugar dissolv
; ed, But the fatal consequences Of its use Ii
. sugar manufactures, are easily to be fore
seen, and know they are but too surely re
allied, as often as the application Of il is at
tempted, that can allow myself to believ
! that the subacetate of lead can ever becom
.r the basis of process for extracting sugar
= This is not the case with tannin, or wit
monohydrated phosphoric acid. These tw
agents coagulate the fermeniing principles
: and precepitate the matters which form them
&c and purify in its cold state the sap or juice
l. the beet, in a manner which renders thei
T. application possible.