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

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_Kiln-drying of breadstuffs, and exclusion of air_.--The injury
which our breadstuffs sustain by the large proportion of water can
of course be prevented only by careful drying before shipment, and
by the employment of barrels rendered as impervious as possible to
the influence of atmospheric moisture.

In my first report, I have spoken favorably of the process of drying
by steam, according to the plan patented by Mr. J.R. Stafford. I
still think this mode possesses great advantages over those
previously followed, and which almost always injured the quality of
the grain or flour: but from some trials which I have made during
the past year, it is inferred that the exposure to the heat is
perhaps usually not sufficiently prolonged to answer the purpose
intended by the operation. I have often observed that samples of
wheat flour, after being exposed to the heat of the salt water-bath
oven (220 deg. Fahr.) for two or three hours, lost weight by a
further continuance of the heat. An apparatus has been patented by
Mr. J.H. Tower, of Clinton, N.Y., consisting of a cylinder of square
apartments or tubes, into which the grain or flour is introduced,
and subjected to heat while in rapid revolution. I examined samples
which had been subjected to this operation, and ascertained that
wheat flour, originally containing 14.80 per cent. of water, had the
proportion reduced to 10.25 per cent., while in wheat the proportion
of water was reduced from 14.75 to 8.55 per cent.

Now it is probable that by either of the above modes, and perhaps by
many others, the various kinds of breadstuffs may be brought to that
degree of dryness which, with ordinary care, shall protect them from
subsequent injury; but in order to secure this advantage, the
operation must be carefully performed, and experiments must be made
to ascertain how long an exposure to heat is necessary to bring the
sample to the proper degree of dryness, and to determine whether in
any respect its quality is impaired. It has already been stated that
absolute desiccation is not necessary, even were it attainable; but
any process in order to be effective should reduce the proportion of
water to about six, or at most seven per cent.

I have heretofore adverted to the great care employed in the drying
of grain in various foreign countries, and to which the preservation
of it for a great number of years is to be ascribed.

The operation is not conducted in the hurried manner which is here
thought to be so essential, but is continued long enough to effect
the intended object. Thorough ventilation, as well as the proper
degree of drying, and which is equally important, is thus secured.

It is said that in Russia the sheaves of wheat, carried into the
huts, are suspended upon poles and dried by the heat of the oven.
The grain shrinks very much during this process, but it is supposed
to be less liable to the attacks of insects, and preserves its
nutritive qualities for many years. During the winter, it is sent to
market.--("The Czar, his Court and People." By John S. Maxwell, p.
272.)

With all the necessary attention which may be paid to the proper
drying of our breadstuffs intended for export, another point is of
equal importance, viz., the shipment in vessels rendered as
impervious as possible to the influence of atmospheric moisture. For
however carefully and thoroughly the drying, especially of wheat
flour or maize meal, may have been performed, it will be nearly
useless if the shipment is afterwards made in the barrels commonly
employed.[29] And it is very certain that the transport and shipment
of grain in bulk, as usually conducted, are attended with great
loss. This difficulty might be removed at a trifling expense by
adopting the plan suggested in the preceding report, and to which I
would again respectfully call the attention of those who are engaged
in this branch of trade.

I might here adduce a mass of testimony showing the importance of
the matters just referred to, but will only advert to the following
statements, which although made in allusion principally to maize,
are equally applicable to our other breadstuffs. Maize meal, if kept
too long, "is liable to become rancid, and it is then more or less
unfit for use. In the shipments made to the West Indies, the meal is
commonly kiln-dried, to obviate as much as possible this tendency to
rancidity." "When ground very fine, maize meal suffers a change by
exposure to the air. It is oxygenated. It is upon the same principle
that the juice of an apple, after a little exposure to the air, is
oxygenated, and changes its character and taste. If the flour could
be bolted _in vacuo_, it would not be changed." "Intelligent writers
speak of the necessity of preparing corn for exportation by
kiln-drying as indispensable. Without that process, corn is very
liable to become heated and musty, so as to be unfit for food for
either man or beast. The kiln-dried maize meal from the Brandywine
Mills, &c., made from the yellow corn, has almost monopolized the
West India trade. This process is indispensable, if we export maize
to Europe. James Candy says that from fifty years experience he has
learned the necessity of this process with corn intended for
exportation." "I have often found the corn from our country when it
reached its destination, ruined by heating on the voyage. It had
become musty and of little or no value. Kiln-drying is absolutely
necessary to preserve it for exportation. We must learn and practice
the best mode of kiln-drying it.[30]"

_The nutritious value of the "whole meal" of Wheat, as compared
with that of the fine flour_.--The question whether what is
called the whole meal of wheat, or that which is obtained by the
mixture of the bran, contains more nutritious matter than the
fine flour, is one of great importance. In my former report, I
adverted to the statement made in regard to it by Professor
J.F.W. Johnston, and which seemed to be almost conclusive in
favor of the value of the whole meal. During the past year,
however (1849), M. Eug. Peligot, an eminent French chemist, in an
elaborate article "On the Composition of Wheat," to which more
particular reference will be made hereafter, combats the opinion
that the bran is an alimentary substance. He observes that "the
difficulty of keeping the bran in flour intended for the
manufacture of bread of good quality appears to result much less
from the presence of the cellulose (one of the constituents of
woody matter) contained in wheat than that of the fatty matter.
This is found in the bran in a quantity at least triple of that
which remains in the flour, and the bolting separates it from the
ground wheat not less usefully than the cellulose itself."[31] M.
Millon objects entirely to the views of M. Peligot on this point,
and states some facts which are especially worthy of
consideration. He asserts that, according to the views of the
last named chemist, the separation at most of one part of fatty
matter sacrifices fifteen, twenty, and even twenty-five per cent.
of substances which are of the highest nutritive value. This
abstracts from wheat, for the whole amount raised in France, the
enormous sum of about two hundred millions of pounds annually.

It seems that in France the question whether the bolting of flour is
advantageous has always been decided in the most arbitrary manner.
An ordinance of Louis XIV., issued in 1658, prohibited, under a very
heavy penalty, the regrinding of the bran and its mixture with the
flour; this, with the mode of grinding then in use, caused a loss of
more than forty per cent.--(Comptes Rendus, February 19th, 1849.)

In large cities and elsewhere, there seems for some time to have
been a growing prejudice against the use of brown bread; and it is
said that now nearly all the peasantry of France bolt their flour.
The increase of this practice, according to M. Millon, threatens
the nation with an annual loss of from two to three hundred millions
of francs. If the bran was entirely valueless, there would be a loss
of more than one million a day.

It is quite difficult to determine the precise amount of bran which
may have been removed from wheat, for various samples contain such a
different proportion of bran that in the one case a removal of ten
per cent, leaves more bran in the flour than a bolting of five per
cent. in another.

The following is an analysis of bran by M. Millon; the sample being
a soft French wheat grown in 1848:--

Starch, dextrine and sugar 53.00
Sugar of liquorice 1.00
Gluten 14.90
Fatty matter 3.60
Woody matter 9.70
Salts .50
Water 13.90
Incrusting matter and aromatic principles (by difference) 3.40
------
100.

The conclusion to be drawn from this analysis is, that bran is an
alimentary substance. If it contains six per cent. more of woody
matter than the rough, flour, it has also more gluten, double that
of fatty matter, besides two aromatic principles which have the
perfume of honey, and both of which are wanting in the fine flour.
Thus by bolting, wheat is impoverished in its most valuable
principles, merely to remove a few hundredths of woody matter.

The economical suggestion which springs from these views is, that
the bran and coarse flour should be reground and then mixed with the
fine flour. Millon states that he has ascertained, by repeated
experiments, that bread thus made is of superior quality, easily
worked, and not subject to the inconvenience of bread manufactured
from the rough flour, such as is made in some places, and especially
in Belgium.

Opinions similar to those above noticed are entertained by Professor
Daubeny. "The great importance attached to having bread perfectly
white is a prejudice," he says, "which leads to the rejection of a
very wholesome part of the food, and one which, although not
digestible alone, is sufficiently so in that state of admixture with
the flour in which nature has prepared it for our use." After
quoting the remarks of Professor Johnston on the same side of the
question, he adds, "that according to the experiments of Magendie,
animals fed upon fine flour died in a few weeks, whilst they thrived
upon the whole meal bread." Brown bread, therefore, should be
adopted, not merely on a principle of economy, but also as providing
more of those ingredients which are perhaps deficient in the finer
parts of the flour.--("Gardeners' Chronicle," January 27th, 1849, p.
53.)

The remarks of Dr. Robertson may also be here introduced. "The
advantage," he observes, "of using more or less of the coverings of
the grain in the preparation of bread has often been urged on
economical principles. There can be no doubt that a very large
proportion of nutritive matter is contained in the bran and the
pollard; and these are estimated to contain about one-fifth part of
the entire weight of the wheat grain. It is, unquestionably, so far
wasteful to remove these altogether from the flour; and in the case
of the majority of people, this waste may be unnecessary, even on
the score of digestibility."[32] This subject can also be rendered
apparent to the eye. If we make a cross section of a grain of wheat,
or rye, and place it under the microscope, we perceive very distinct
layers in it as we examine from without inwards. The outer of them
belong to the husk of the fruit and seed, and are separated as bran,
in grinding. But the millstone does not separate so exactly as the
eye may by means of the microscope, not even as accurately as the
knife of the vegetable anatomist, and thus with the bran is removed
also the whole outer layer of the cells of the nucleus, and even
some of the subjacent layers. Thus the anatomical investigations of
one of these corn grains at once explains why bread is so much the
less nutritious the more carefully the bran has been separated from
the meal.[33] There can therefore be little doubt that the removal
of the bran is a serious injury to the flour; and I have presented
the above array of evidence on this point in the hope of directing
public attention to it here, as has been done in various foreign
countries.

After this, it will easily be inferred that I am not disposed to
look with much favor upon the plan proposed by Mr. Bentz for taking
the outer coating or bran from wheat and other grains previously to
grinding.[34] Independently of the considerations which have already
been presented, it is far from being proved, as this gentlemen
asserts, that the mixture of the bran with the meal which results
from the common mode of grinding is the chief cause of the _souring_
of the flour in hot climates. On the contrary, the bran is perhaps
as little liable to undergo change as the fine flour, and then the
moistening to which, as I am informed, the grain is subjected
previously to the removal of the husk, is still further
objectionable, and must be followed by a most carefully-conducted
process of kiln-drying.

_Nutritious properties of various articles of food_.--There seems to
be some difference of opinion in regard to the nutritious properties
of various kinds of food. It is generally, however, agreed that
those which contain the largest proportion of nitrogenous matters
are the most nutritious. It is on this account that haricots, peas,
and beans, form, in some sort, substitutes for animal food. Tubers,
roots, and even the seeds of the cereal grasses, are but moderately
nutritious. If we see herbivorous animals fattening upon such
articles, it is because, from their peculiar organisation, they can
consume them in large quantities. It is quite doubtful whether a man
doing hard work could exist on bread exclusively. The instances
which are given of countries where rice and potatoes form the sole
articles of food of the inhabitants, are believed to be incomplete.
Boussingault states that in Alsace, for example, the peasantry
always associate their potato dish with a large quantity of sour or
curdled milk; in Ireland with buttermilk. "The Indians of the Upper
Andes do not by any means live on potatoes alone, as some travellers
have said they do: at Quito, the daily food of the inhabitants is
_lorco_, a compound of potatoes and a large quantity of cheese. Rice
is often cited as one of the most nourishing articles of diet. I am
satisfied, however, after having lived in countries where rice is
largely consumed, that it is anything but a substantial, or, for its
bulk, nutritious article of sustenance."--("Rural Economy," Amer.
edition, p. 409.) These statements are further confirmed by the
observations of M. Lequerri, who, during a long residence in India,
paid particular attention to the manners and customs of the
inhabitants of Pondicherry. "Their food," he states, "is almost
entirely vegetable, and rice is the staple; the inferior castes only
ever eat meat. But all eat _kari_ (curry), an article prepared with
meat, fish, or vegetable, which is mixed with the rice, boiled in
very little water. It is requisite to have seen the Indians at their
meals to have any idea of the enormous quantity of rice which they
will put into their stomachs. No European could cram so much at a
time; and they very commonly allow that rice alone will not nourish
them. They very generally still eat a quantity of bread."[35] In
regard to the proportion of nutritious matter contained in grains of
various kinds, it may be remarked that the tables which have been
constructed as the results of various experiments are liable to an
objection, which will be more particularly adverted to under another
head. For example, two substances, by the process of ultimate
analysis, may exhibit the same proportion of nitrogenous matter, and
still differ very materially in their value as articles of food.
Much depends on the digestibility of the form in which this matter
is presented to the digestive organs. A strong illustration is
afforded in the case of hay, the proportion of nutritive matter of
which, about 9.71, would certainly not represent its power of
affording nourishment to the human system. It is in truth quite
impossible to arrive at any other than approximate results from the
operations of chemistry, as to the amount of nutriment contained in
a given quantity or weight of any article of food.[36] It is perhaps
not irrelevant to notice in this place some of the researches which
have recently been made upon fermentation, and particularly its
effects in the manufacture of bread. It appears that when this
process is brought about by the addition of yeast or leaven to the
paste or dough, the character of the mass is materially altered. A
larger or smaller proportion of the flour is virtually lost.
According to Dr. William Gregory the loss amounts to the very large
proportion of one-sixteenth part of the whole of the flour. He says,
"To avoid this loss, bread is now raised by means of carbonate of
soda, or ammonia and a diluted acid, which are added to the dough,
and the effect is perfectly satisfactory. Equally good or better
bread is obtained, and the quantity of flour which will yield
fifteen hundred loaves by fermentation, furnishes sixteen hundred by
the new method, the sugar and fibrin (gluten) being
saved."--("Outlines of Chemistry," p. 352.)

Another author, Dr. R.D. Thomson, states, as the results of his
experiments upon bread produced by the action of hydrochloric acid
upon carbonate of soda, "that in a sack of flour there was a
difference in favor of the unfermented bread to the amount of thirty
pounds thirteen ounces, or in round numbers, a sack of flour would
produce one hundred and seven loaves of unfermented bread, and only
one hundred loaves of fermented bread of the game weight. Hence it
appears that in the sack of flour by the common process of baking,
seven loaves, or six-and-a-half per cent, of the flour are driven
into the air and lost."--("Experimental Researches on the Food of
Animals," &c., p. 183.)

The only objection to the general introduction of this process seems
to be the degree of care and accuracy required in properly adjusting
the respective qualities and quantities of acid and alkali, and
which could seldom be attained even by those who are largely engaged
in the manufacture of bread.

I cannot leave this subject without adverting to a practice which
has prevailed in England and France, and perhaps also in this
country, of steeping wheat before sowing it in solutions of arsenic,
sulphate of copper, and other poisonous preparations.

The result has been that injurious effects have often followed, both
to those who are employed in sowing such grain, and to those who
have used the bread manufactured from it. The great importance of
the subject led to the appointment of a commission at Rouen, in
France, in December, 1842, having for its object to determine the
best process of preventing the smut in wheat, and to ascertain
whether other means less dangerous than those above noticed were
productive of equally good results. The labors of this commission
extended over the years 1843-'44-'45, and the experiments were
repeated two years following on the farm of Mr. Fauchet, one of the
commission, at Boisquilaume, in the department of the Seine
Inferieure.

The results arrived at by this commission are--1st. That it is not
best to sow seed without steeping. 2nd. That it is best to make use
of the sulphate of soda and lime process, inasmuch as it is more
simple and economical, in no way injurious to the health, and yields
the soundest and most productive wheat. 3rd. That the use of
arsenic, sulphate of copper, verdigris, and other poisonous
preparations, should be interdicted by the government.--("Gardeners'
Chronicle," January 6th, 1849, pp. 10 and 11.)

_Composition of wheat and wheat flour, and the various modes of
determining their nutritive value_.--In my former report it was
stated that the analyses of the various samples of wheat, the
results of which were there given, had been chiefly directed to the
determining the amount of rough _gluten_ which they contained. My
reasons for adopting this plan, and the arguments in favor of its
general accuracy, as compared with other modes of analysis, and
especially that by which the ultimate composition is ascertained,
were also detailed. A more full examination of this subject has
served only to strengthen the opinion already expressed, that for
the great purpose to be answered by these researches, the process
which I have adopted is, to say the least, as free from objection
as any other, and if carefully and uniformly carried out, will truly
represent the relative values of the several samples of wheat flour.
As this is a matter of much consequence in a practical point of
view, I trust I shall be excused for introducing some additional
facts in regard to it.

The term _gluten_ was originally applied to the gray, viscid,
tenacious, and elastic matter, which is obtained by subjecting wheat
flour to the continuous action of a current of water. But it appears
that this is a mixture of fibrine and caseine, with what is now
called _glutine_, and a peculiar oily or fatty matter. Now these
substances may be separated from each other, but the processes
employed for this purpose are tedious, and to insure accuracy the
various solvents must be entirely pure--a point which, especially in
the case of alcohol and ether, is not ordinarily easy to be
attained. This will be rendered still more evident by a reference to
a French process, which will hereafter be noticed.

But were it much less difficult in every case accurately to separate
the constituents of gluten, it would not, in my opinion, be of the
least practical utility. It is to the peculiar mechanical property
of this gluten that wheat flour owes its superior power of detaining
the carbonic acid engendered by fermentation, and thus communicating
to it the vesicular spongy structure so characteristic of good
bread.[37] It may also be added, that the results of more than one
hundred trials have satisfied me that a diminution or loss of
elasticity in the gluten is the surest index of the amount of injury
which the sample of flour has sustained. Whether, therefore, the
sample contains a certain proportion of nitrogen, or whether it
contains albumen, fibrine, and caseine in sufficient quantity, it
may still want the very condition which is essential to the
manufacture of good bread. My objection, therefore, to the mere
determination, however accurate, of the proportion of nitrogen
contained in wheat flour, or of the various principles which form
the gluten, is, that it does not represent the value of the various
samples for the only use to which they are applied, viz., the making
of bread. The remarks of Mulder, the celebrated Dutch chemist, upon
the subject of manures, are so applicable to this point that I
cannot refrain from quoting them. "It has," he says, "become almost
a regular custom to determine the value of manures by the quantity
of nitrogen they yield by ultimate analysis. This method is entirely
erroneous; for it is based upon the false principle, that by
putrefaction all nitrogeneous substances are immediately converted
into ammonia, carbonic acid, and water! But these changes sometimes
require a number of years. Morphine, for example, is prepared by
allowing opium to putrefy; and the process for preparing leucin, a
substance which contains 10.72 of nitrogen, is to bring cheese into
putrefaction. Cheese, therefore, does not perhaps in a number of
years resolve itself into carbonic acid, ammonia, and water, but
produces a crystalline substance, which contains no ammonia. Hence
the proportion of nitrogen yielded by manures is not a proper
measure of their value, and therefore this mode of estimating that
value ought to be discontinued."[38] We infer, therefore, that the
proportion of nitrogen furnished by food of various kinds is not the
true measure of their nutritious value, and cannot for practical
purposes take the place of that process by which the amount of rough
gluten is determined.