The Commercial Products of the Vegetable Kingdom by P. L. Simmonds

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In 1840, we imported from Java 75,533 cwt.; in 1841, 87,342 cwt.; in
1842, 24,922 cwt.; in 1843, 35,161 cwt.; and in 1844, about 72,000
cwt.; but most of this was only sent to Cowes, for orders, to be
transhipped to the Continent.

_Philippines_.--The exports from Manila into this country in 1841,
were 133,482 cwt.; in 1842, 63,464 cwt.; and in 1843, 48,977 cwt. In
the fifteen years between 1835 and 1850, the export of sugar from the
Philippine Islands more than doubled:--

Tons.
1835 11,542
1836 14,875
1837 12,293
1838 12,375
1839 15,631
1840 16,563
1841 15,321
1842 18,540
1843 22,239
1844 21,528
1845 24,500
1850 28,745

About a third of this is raw sugar, the rest is clayed or refined. It
is singular, that though these islands belong to Spain, the export of
this staple product to that country should be limited to about 600
tons; America taking about one-sixth, and England and her colonies the
remainder. There is now an increased demand for the Australian
colonies, consequent upon the large influx of population to that
quarter.

Export of sugar from Manila in 1850.

Piculs.
To Great Britain 146,926
" Continent of Europe 50,830
" Australian Colonies 142,359
" Singapore, Batavia, and Bombay 12,749
" California and the Pacific 29,144
" The United States 77,919
-------
459,927

The sugar cane occurs in a wild state on many of the islands of the
Pacific, but in no part of the American continent, notwithstanding a
contrary opinion has been expressed.

The following are the chief varieties cultivated in the West Indies,
Louisiana, the East Indies, and Mauritius:--

1. Common or creole cane, so called from being introduced from the New
World.

2. Yellow Bourbon.

3. Yellow Otaheite.

4. Otaheite with purple bands.

5. Purple Otaheite.

6. Ribbon cane.

My friend, Mr. L. Wray, in his "Practical Sugar Planter," considers
the Bourbon, and yellow, or straw-coloured Otaheite cane, as
identical, but merely altered by change of soil and climate. The yield
from these cane-plants seems to be about the same in either Indies,
viz., in good land about two-and-a-half tons of dry sugar per
acre--sometimes three tons.

A very large species of red cane, grown at Gowhatty, in Assam, is
made favorable mention of for its strength of growth, early maturity,
and juiciness; and Mr. Wray strongly recommends the introduction into
the West Indies of another fine variety, generally grown in the
Straits' settlements, where it is known by the name of the Salangore
cane. He considers they would ratoon better than any other cane, and
the return from it is on the average 3,600 lbs. of dry sugar to the
acre.

"For my own part, I have always reckoned as an average, 3,600 lbs.
of dry sugar to the acre as the return this cane will give, on
anything like good land, in the Straits, according to the present
imperfect mode of expressing and manufacture; but, considering the
surpassing richness of land in the West India Islands, Demerara, and
Mauritius, I should not be in any way surprised to find that it
would there give even three tons an acre.

The Salangore cane grows firm and strong; stands upright much better
than the Otaheite; gives juice most abundantly, which is sweet and
easy of clarification, boils well, and produces a very fine, fair
sugar, of a bold and sparkling grain."

Much discussion has arisen on the subject of raising the sugar cane
from seed, and the possibility has been universally denied among the
planters and agricultural societies of the West India colonies. Mr.
Pritchard, a sugar planter of Louisiana, in the "United States Patent
Report for 1850," however, states:--

"It is an error to suppose that the cane cannot be propagated from
the seed. This may be the case when the seed is obtained from plants
that have been produced for a number of years from buds, or eyes.
All plants that have been produced in this way for a series of
years, lose the faculty of forming prolific seeds; and the sugar
cane is governed by the same laws which govern the whole vegetable
kingdom. It cannot, therefore, be expected to produce seeds after it
has been cultivated for a great length of time."

The sugar cane is composed of water, woody fibre, and soluble matter,
or sugar. In round numbers it may be stated that the proportions are
72 per cent. of water, 10 per cent. of woody fibre, and 18 per cent.
of sugar.

The fluid contents of a cane, according to Dr. Evans, contain 90 per
cent. of the entire structure of the stem.

1,000 grains of sugar cane, being burnt, gave 71/2 grains of ash, which,
on analysis, furnished the following components:--

Silica 1.78
Phosphate of lime 3.41
Red oxide of iron and clay .17
Carbonate of potash 1.46
Sulphate of potash .15
Carbonate of magnesia .43
Sulphate of lime 6
----
7.46

The following is the quantative analysis of a portion of soil taken
from the surface of a cane field, on the Diamond estate, in St.
Vincent, West Indies: --

Alumina soluble in acids 12.87
Organic matter 11.26
Gypsum .23
Carbonate of lime 12.52
---- of magnesia .71
Oxide of iron 8.51
Oxide of manganese .33
Insoluble silicious and aluminous matter 53.57
------
100.00

The sugar of the cane and grape sugar are distinguished by the
following difference in their elements, as proved by analysis:--

Cane sugar. Grape sugar.
Carbon 12 12
Hydrogen 10 12
Oxygen 10 12
Water 1 2

There is a remarkable difference, however, between their fermentable
properties. When a solution is made of the same quantities of these
two sugars, in equal proportions of distilled water, it will be
necessary to add eight times as much of the same ferment to induce
alcoholic fermentation in the solution of cane sugar, as in that of
grape sugar. Under the action of a larger quantity of ferment, cane
sugar is transformed into grape sugar.

If you cut a sugar cane in two, and examine the interior part of it
with a magnifying glass, you perceive the crystals of sugar as
distinct and as white as those of double-refined sugar. The object of
the operator should be then either to extract those crystals without
altering their color, or, if that be found impracticable, to separate
them from the impurities mixed with them, while the juice is in its
natural state, and yet contains but little coloring matter. Instead of
this, the juice is limed while all the impurities are in it. In
separating the feculencies from the juice and uniting them in large
flakes, lime dissolves a portion of them and forms with them coloring
matter, which we all know at once discolors the juice, when lime is
used in excess. Afterwards heat is applied, either in clarifiers or in
the grand copper, but most of the impurities found in the juice will
decompose, and burn at a degree of heat far below the boiling point,
say at 120 deg. of Fahrenheit. This is shown by the thick scales
continually forming in the grande. From that degree of heat the
decomposition goes on in the clarifier till the juice is drawn, and
continues in the grande so long as there are feculencies left. This
decomposition greatly increases the quantity of coloring matter, so
that, as the juice is being clarified, it loses in color what it gains
in purity. And here let me show the relative value of the "grande" and
of clarifiers as agents of clarification. In the grande, if it is well
attended to, the scummings are taken up as soon as they rise. A
portion of them is removed before they begin to decompose, and the
process goes on, so that before the juice reaches the boiling point
nearly all the feculencies are removed, and the source of coloring
matter is removed with them. Clarifiers reach the boiling point much
quicker, and cannot easily be scummed. The general practice is to
bring them to that point without scumming, to let the feculencies
separate from the juice by cooling and by rest, and to wash out the
clarifiers every second or third time they are filled. Heat and
alkalies acting in them upon the accumulated feculencies of one, two,
or three charges, dissolve a much larger portion of those feculencies
than they can possibly do in the grande. The formation of coloring
matter continues during the time of rest, and accordingly planters,
after repeated trials, generally agree that juice well clarified in
the grande, has a lighter and brighter color, and makes better sugar
than that obtained from clarifiers.

The first object of research should be to find means of clarifying the
juice without creating coloring matter. It is said that presses
something like those used to press cotton, have lately been
successfully employed in the West Indies, instead of rollers; that the
juice obtained is much purer, and that a much larger quantity of it is
extracted from the cane. If so, this will be a great improvement, and
the first step of the process I should recommend. From juice thus
obtained, I have no doubt that all impurities less soluble than itself
may be separated by mechanical means before heat and alkalies are
applied, or at least with a very small quantity of alkalies. All other
liquids, all fatty substances and oils, except cotton seed oil, are
clarified by a very rapid process. Cane juice can no doubt be
clarified by similar means, and if this were accomplished the process
of sugar making would be very much simplified.

The clarified juice might then be placed in an evaporator, heated by
the waste steam of the engine; then be limed and scummed if necessary,
and concentrated to fifteen or sixteen of the prese sirop; then
purified by filtration through animal charcoal, if white sugar was
wanted, or by rest for other qualities; and finally concentrated in
vacuum pans of great power, such pans as Mr. Thomas A. Morgan, of
Louisiana, now uses, and which, I am informed, are only made in
America.

The superiority of the vacuum pan is not universally admitted, and we
are told that in France it is superseded by open pans, similar to
those called in America "Mape's Evaporators." However this may be, I
cannot help believing that the vacuum pan has many decided advantages
over all others. One is manifest; the sugar may be grained in the pan,
and the granulation is completely under the control of the operator.
He may accelerate or retard it at pleasure; he may carry it so far
that sugar will not run from the pan, and will have to be taken out of
it; he may so conduct the operation as to increase, almost at will,
the size and hardness of the crystals. This last is an indispensable
requisite if the practice of draining sugar in pneumatic pans should
be adopted.

The atmospheric pressure is made too powerful for sugars boiled in any
other manner; it breaks and destroys the crystals, and in a very few
days sets the sugar to fermenting.

The pneumatic draining of sugar has many things to recommend it--the
usual loss by drainage is avoided, sugar is got ready for market day
by day, as it is made, and it may be bleached by pouring white syrup
over it and forcing it through the mass. It is said that the process
is attended with considerable loss in weight, but as all that drains
from the pan may be boiled over once or twice, it is not easy to
conceive how the loss can occur.

Cane juice contains many ingredients besides sugar, the principal of
which are albumen, gluten, gum, starch, resin, wax, coloring matter,
and certain salts, all of which, either collectively or individually,
have the power of preventing granulation, as may be proved by their
addition to a syrup of pure sugar, which will then defy all attempts
to make it crystallise. If, therefore, we want to make good sugar, we
must endeavour to free our cane juice as much as possible from those
substances.

Now, cane juice is no more the sap of the cane, than apple juice is
that of the apple tree; it is the natural product of the cane, and, in
all probability, would contain but a small proportion of these foreign
matters if it could be expressed without being accompanied by the sap,
they being the natural constituents of the last-named fluid. A patent
has, I believe, been lately taken out for separating the cane juice
without the sap. However, in the absence of such an improvement, much
may be done by care and attention at the mill; the green bands and
trash which usually accompany the canes from the field, should,
therefore, be carefully removed before they are passed through, as
they contain no saccharine matter, abound in the deleterious
substances already mentioned, and communicate a bad color to the
juice; therefore, _the ripe cane only should pass through the mill_.
There are but few planters who have not had to contend with sour
juice, and they attribute the difficulty they experience in making
sugar therefrom, to the presence of acetic acid, or vinegar; but this
is quite an erroneous idea, as the acetic acid is very volatile, and
evaporates quickly on the application of heat, which may be proved by
throwing a gallon of strong vinegar into a pan of liquor; it will do
no harm, provided it be boiled before tempering; on the contrary, the
effect, if it be properly done, will be beneficial, as it will promote
the coagulation of the albumen; it is the gum which is always formed
during the acetous fermentation of sugar that prevents granulation;
hence, then, acidity is strictly to be guarded against, as
fermentation once commenced, it will be impossible to make good sugar,
it will continue throughout the process, and even in the hogshead; so
that canes should be ground as soon as possible after they are cut,
and all rat-eaten and broken ones carefully excluded. Canes may,
however, be kept some days without fermenting, provided they be not
broken or damaged, it being, as we said before, the mixture of the sap
and the cane juice that makes the liquid so prone to fermentation; and
the mill, gutters, and everything with which the juice is likely to
come in contact, should be kept carefully clean, and whitewashed
immediately after, and the whitewash removed before use, as acetate of
lime being an exceedingly soluble and deliquescent salt, will not
improve the quality of the sugar; whilst the gutter should be short,
and sheltered from the sun's rays, they having the effect of greatly
expediting chemical action.

I shall say no more on this subject, but will proceed to consider the
mode of tempering and clarifying cane juice, and the action of lime on
the various substances contained therein. The expression "tempering"
has, I presume, been, adopted in consequence of the use of tempered
lime for the purpose of precipitating the feculencies, held in
solution in the cane juice, into a state of suspension; and
clarification is the process by which we afterwards clear the liquor
of these and other foreign matter. Now, as I before observed,
"fermentation should be most strictly guarded against;" our first
efforts should be directed to free the cane juice from those
substances most conducive to that process; and on inquiry we find
these to be albumen and gluten; so far, however, from getting rid of
them in cold tempering, we adopt a course which retains them
permanently in solution, as lime has the power of rendering them
permanently soluble, and of forming soapy compounds with resin, wax,
and chlorophyle, or the green coloring matter of leaves, forming an
insoluble compound with and precipitating only the starch, and
converting at the same time the green color of the chlorophyle (which
is, in all probability, attached to the resin), into a dark brown, of
a greater or less intensity, according to the composition of the cane
juice, and, consequently, the quantity of lime required; it follows,
therefore, as a matter of course, that if juice be tempered before
these substances have been removed, they must be permanently retained,
and they have all the power of preventing granulation.

Albumen, and gluten are both coagulable by heat; if, therefore, we
raise the liquor to the boiling point prior to applying the lime,
taking care to remove the scum as soon as it shows signs of breaking,
and continuing the boiling until the scum thrown to the surface
becomes inconsiderable, we shall find that the albumen and gluten, in
coagulating and rising, have carried with them the small particles of
woody fibre, the wax, and a large proportion of the coloring matter,
and that the lime will now throw down the starch, and any other little
impurities remaining in suspension in the liquor, leaving it perfectly
clear and bright. Tempering is an exceedingly delicate chemical
operation, and I have no hesitation in saying, that on its proper
performance depends the quality of the produce. The following simple
experiments, which all have it in their power to try, will, if they
give themselves the trouble, fully satisfy them of two important
points--the superiority of the hot over the cold mode, and the
necessity for great attention to the operation of tempering. Let them
take a tumbler of cane-juice and a bottle containing lime water, add
the latter to the former by drops, pausing and stirring between each,
and they will find that, after the addition of a certain quantity, the
opaque gummy appearance of the liquor undergoes a change, and the
impurities contained in it separate into flakes, which increase in
size with each drop of lime added, until they become extinct, and the
supernatant liquor perfectly transparent; this is the precise point at
which the liquor is tempered, and each drop of lime added after this,
causes the flakes to diminish rapidly in size, at last entirely to
disappear (being re-dissolved), and the liquor to resume its former
gummy appearance; it is, therefore, evident that there should be no
such expressions as tempering high or low.

The reason why some liquor is so difficult to clean is, that it is
either tempered high or low; if it be exactly tempered, the impurities
contained in it being entirely separated and thrown out of solution,
rise to the surface immediately on the application of heat, and are
easily removed; but if there be too little lime, a great portion
remains in solution, and if too much, a proportional quantity is
re-dissolved; and in either case cannot be removed by any mechanical
means. It is, therefore, necessary to have some precise test for the
application of lime.

As regards the superiority of the hot over the cold tempering, let any
one take, in separate vessels, two gallons of cane-juice, and temper
one, adding the lime in small quantities--say, of three grains at a
time--and keeping an account of the quantity used; he will find that
the first portions produce no effect whatever, and that it is only
after the addition of a considerable quantity that the desired
precipitation of the impurities manifest itself. Why is this? Because
albumen, gluten, resin, and chlorophyle, being soluble in lime, lime
is equally so in them, and they must first be saturated before it will
produce any other effect. Let the liquor thus tempered, be then placed
on one side. Put the other gallon over a fire, and boil it, removing
the scum just before, and during, ebullition; let it then be taken off
the fire, and tempered in the same way as the other. The very first
quantity of lime added causes the appearance of the floccy
precipitate; and if the addition of the lime be continued until it be
precisely tempered, it will be found that the hot possesses the
following advantages over the cold-tempered liquor:--In a quarter of
an hour its impurities will have subsided to a sixteenth of its bulk,
leaving the supernatant liquor as bright and clear as pale brandy;
while those in the other have only sunk to one-quarter of its bulk.
The color of the former clear liquor will not be less than one-half
the intensity of that of the latter. The lime used in the hot has been
less by one-third than the quantity used in the cold tempering.

Of course, on level estates there is little difficulty in tempering
liquor, but on hilly properties scarcely two pans will require the
same quantity.

It is generally believed that the object of adding lime to cane-juice
is for the purpose of neutralising an acid, and it is to the reception
of this fallacious idea that it is indebted for its long and continued
use, and the present backward state of sugar manufacture is
attributable: I unhesitatingly assert that, if there be an acid
present in the cane-juice, the addition of lime to it will be
injurious instead of beneficial. There are only four acids that we
could expect to find in cane juice--mucous, saccholactic or saclactic,
oxalic, and acetic acids. The three first named of these, however,
have never been traced, even in the most minute quantities; and if the
latter be present, which, unfortunately, is but too often the case,
the addition of lime would only result in the formation of acetate of
lime, which is, as I have already observed, an exceedingly difficult
crystallisable, very soluble, and deliquescent salt. It has a bitter,
saline taste; 100 parts consist of 64.5 acid, 35.5 lime, and it is
easily recognisable by its taste in the molasses made from sour
cane-juice: so that, supposing the cane-juice sour, every pint of acid
present would require nearly half a pound of lime for its
neutralisation, independent of the quantity required for the tempering
or precipitation of the feculencies contained in it, and would result
in the formation of one-and-a-half pound of the above mentioned highly
deleterious salt.

Suppose we boil the cane-juice prior to tempering it, we then drive
off a great portion of acetic acid, much less lime will be required,
and if we could, by filtration or subsidence, get rid of the
precipitated feculencies, we should make a tolerably good sugar; but
as, under the present plan, we have no means of so doing, the acetic
acid, which is forming during the whole process of evaporation (as
fermentation still goes on), unites with the lime before it can be
dissipated by the heat, and thus not only forms acetate of lime, but
causes the re-solution of the precipitated feculencies, thus rendering
it necessary to add a fresh portion of lime in the tache, a proceeding
always to be avoided, if possible, but generally necessary in boiling
down sour liquor. Take a small portion of cane-juice (hot or cold) in
a tumbler, and temper it with lime until the feculencies are
precipitated and the flakes perfectly visible, then add vinegar by
drops, and it will be found that the flakes will speedily disappear
and be re-dissolved, showing that lime has a greater affinity for
acetic acid than starch, and that, although when added to sour
cane-juice, it neutralises the acidity, still that result is a
consequence, not the cause, of the application, and is highly
injurious. Lime is one of the greatest known solvents of vegetable
matter; it dissolves albumen, gluten, gum and lignin, or woody fibre,
forming soapy compounds with wax, resin, and, chlorophyle. Ordinary
cane-juice contains about three parts of resin to every 100 of sugar,
and the projection of a small piece of soap into a tache full of
granulating syrup will soon convince any one of the effect likely to
result from the presence of that material. Although, by tempering hot,
we get rid of a very great quantity of the substances on which lime
acts injuriously, a considerable portion of them remain in suspension,
the quantity of albumen contained in the cane-juice not being
sufficient to carry them all off by coagulation; on the addition of
the lime, however, they are entirely dissolved and as the impurities
left behind consist chiefly of gluten, the liability of the liquor to
ferment is greatly increased by its retention, that being the
fermenting principle contained in wheat and other vegetable
productions prone to that process.

One hundred parts of Albumen consist of Carbon, 52.88; Oxygen, 23.88;
Hydrogen, 7-54; Nitrogen, 15.70. Gluten, nearly same as Albumen.

-------------+-------+-------+-------+---------+-------++------+--------
100 parts | | | | | ||Excess! Excess
consist of |Carbon.|Oxygen.|Hydro- | Carbon. | Water.|| of | of
| | | gen. | | ||Oxygen|Hydrogen
-------------+-------+-------+-------+---------+-------++------+--------
Lignin, or | | | | | || |
Woody Fibre| 51.45 | 42.73 | 5.82 | or51.45 | 48.55 || |
Starch | 43.55 | 49.63 | 6.77 | 43.55 | 56.45 || |
Sugar | 42.47 | 50.63 | 6.90 | 42.47 | 57.53 || |
Gum | 42.23 | 50.84 | 6.93 | 42.23 | 57.77 || |
Alcohol | 51.98 | 34.32 | 13.70 | 51.98 | 38.99 || | 9.03
Acetic Acid | 50.22 | 44.15 | 5.63 | 50.22 | 46.91 || 2.87 |
Resin | 75.94 | 13.34 | 10.72 | 75.94 | 15.16 || | 8.90
Wax | 81.79 | 5.54 | 12.76 | 81.79 | 6.30 || | 11.01
-------------+-------+-------+-------+---------+-------++------+--------