The Sun.
London, England, 1861-11-26 00:00:00

STARCH MANUFACTURE.

At the commencement of this century the consumption
of starch was so small, and its known commercial applic-
ability so limited, that it was regarded as a comparatively
unimportant manufacture, and occupied but little of the
attention of the scientific and commercial world. It was
then used only in the laundry, at the toilet, and to a limited
extent as food. All those various applications to the arts
and manufactures, which now constitute it so interesting
and important a branch of our commerce had nit then been
discovered; chemistry had not detected its uses, and in
addition to this, the manufacture was fettered by most bur-
densome fiscal restrictions. It is to our increasing know-
ledge of chemistry, and to the removal of these burdens,
that its rapid development is mainly due—a development
that is almost without a parallel in the history of manu-
factures.

The restrictions alluded to were most oppressive. No one
could manufacture starch without a license, and a tenement
rent was exacted. The details of manufacture were subject
to Government regulation, even to the shape of the packing
boxes and the form of the papers. For the neglect of these
regulations heavy fines were imposed, and the whole was
subject to the inspection of an authorized officer, by whom
every packet had to be stamped. In addition to these bur-
dens a duty of 31d. per pound was levied, amounting to
nearly 75 per cent. of the present market value of the
article. Such were some of the hindrance to the extension
of the manufacture up to the year 1833, -whet, our legisla-
tors v,i.o.y front this period that its
rapid development may be dated. Aow:a. the manutacture
of bricks, glass, soap, and vinegar, and as doubtless will
now be the case with paper, the manufacture of starch,
which languished and stagnated under the burden of re-
strictive laws, began instantly to
~improve and extend so
soon as those laws were repealed.
In illustration of this fact, it may be stated that whereas
up to 1833 only five patents had been taken out in connec-
tion with starch, upwards of forty improvements have been
patented since that period. In 1830 the estimated consump-
tion of starch in Great Britain was 2,500 tons ; in 1850 it
had increased tenfold, amounting to no less than, 25,000
tons ; and such is its present consumption, that, according
to a statement made by Professor Crace Calvert, in a paper
on starches, recently read before the Society of Arts, no
less than 300 tons of starch and its products are annually
used in one single print works at Manchester alone.
Before referring to our illustration and the particular
manufacture of starch from lice, a few general remarks on

the chemical properties' And characteristics of starch may
not be uninteresting to the general reader.
Starch is one of the most abundant constituents of vege-
table principles." It is stored up in seeds, roots, and piths of
plants, end by its decomposition furnishes the materials for
keeping up respiration and supplying the animal heat.
From whatever source, starch always presents the same
'chemical characters ; its physical characters varying slightly
with the plant which furnishes it awl the processes followed
for obtaining it. It has an organised structure, and when
examined by the microscope presents the form of rounded
grains or granules, the size and shape of which differ in
the starch of different plants, varying in diameter from
1-1000th to 3-100th of an inch. Each granule is found to
be composed of successive concentric layers, but the outer
layer has a different molecular arrangement from the inter-
nal ones. These layers, however, have been proved by
analysts to have the same ultimate composition, consisting
of 72 parts of carbon and 81 of water. In its pure state
starch is a fine white powder, without taste or smell. It is
not soluble in cold water or alcohol, or ether, but mixed
with boiling water it swells, bursts, and foams a kind of
mucilage which cools into a semi-transparent paste or jelly.
It may also be converted into a jelly by the action of dilute
'acids, and if the temperature of such solution be raised to
212 degs. several changes follow, the first of which is the
production of dextrine, a substance analogous to the proper-
ties of gum. In commerce it is known as " British gum,"
and forms an excellent substitute for gum arable. As calico
printing in is present extraordinary development requires
thousands of tons of soluble material for thickening the
mordants and colours used, a great variety of this class of
artificial gums is prepared. The next change wrought on
the starch by acids is its conversion into glucose or grape
sugar, but in this case starch not only undergoes a:molecu-
lar change, but a cempleto transformation. In beautiful
illustration of this process, it has been lately domor strated
that the sweetening of fruits is due to tho action of the acids
converting the starch existing in them to sugar; and the
curious obse' vation has recently been made, that if paper is
impregnated with starch, and exposed to the rays of the
sun, the starch is slowly converted to sugar. Diastase, or
an albuminous ferment which exists in all grains, and par-
ticularly
in malt, also possesses this property, as exhibited
in the mash-tub of the brewer, and one of the greates t
triumphs of chemistry applied to ph) Biology has been the
discovery of this transforming substance in the saliva and
pancreatic juice of the human system, by which tho starch
taken in food is converted into sugar. It is to the excess of
diastase in the system, and the consequent too rapid and
too copious formation of sugar, that the disease called dia-
betes is now attributed. The diagnosis of this distressing
malady being novrunderstood, we may be permitted to hope
that science will alike discover a remedy, and a more singu-
lar or beautiful illustration of the beneficent uses of cbe-
tnistry could scarcely bo afforded.
It would occupy too much of our space to enumerate all
the various known starches, suffice to allude to sago, arrow-
root, the dahlia-root, beetroot, yams, the manioc-root, and
horse •chesnuts, as being a few of its principal sources, in
addition to those usually resorted to by manufacturers-
-47iz., wheat, potato, and lice. Of these latter we shall now
peak more fully, referring more particularly to lice starch,
which possesses the greatest novelty, and illustrates mere
than any other the progress of chemical science and the in-
creasing range and value of its application to manufac-

Lures.
Wheat starch is the oldest known. It is alluded to by
Pliny in his "Natural History," and the discovery of the
method of its extraction is attributed by him to the inhabi-
tants of the island of Chios. The starches used three cen-
turies ago, when such enormous ruffles and frills were in
fashion, were made from wbeat ; in fact down to modern
tines it was the only known sourco of starch.
In all cereals, starch is associated with an azotised sub -
itance called gluten, and it is the separation of the starch
from this substance that is the aim and likewise the diftl-
/ulty of the manufacturer. In the process of wheat-starch
:baking, this is effected by a system of fermentation.
rushed wheat is mixed with water, when fermentation
quickly commences, and the mixture is allowed to stand for
tome weeks. A foul acid water is produced, called " sour
water," and the putrefaction of the gluten produces a most
offensive odour, The fermentation which arst takes plate