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ONE of the most troublesome
characteristics of articles used for food is their liability to
decomposition. Flesh of all kinds is peculiarly prone to speedy decay; and,
though vegetables are on the whole more durable, yet most of them also soon
become unfit for food. Prior to the beginning of this century, no mode of
preserving animal food on a large scale was known save that of salting.
Consequently, when vessels set out on a voyage that was to last beyond a few
days, their crews had to be provided with stores of salted meat. Now, though
salt preserves flesh from putrefaction, it deteriorates to a certain degree
the quality; and persons who are compelled to use much salted meat without
fresh vegetables are liable to attacks of scurvy and other affections of the
fluids of the body. When salt is applied to fresh meat, a saline liquid or
brine is deposited in the vessel. This is due to the power which the salt
possesses of extracting from meat a large portion of the water or other
soluble matter which enters into its composition. On analysing it, the brine
is found to contain all the ingredients of a concentrated infusion of flesh;
while only fibre is left for the salt to pre-serve. Salting, consequently,
destroys to a great extent the nutritive properties of the flesh; and when
the brine is poured off as waste, it really carries with it more than half
the nourishment contained in the meat. Until a recent period, it might be
said that more British seamen were destroyed by scurvy, originating in the
want of vegetable food and in the constant use of salted provisions, than by
all other causes combined. When Lord Anson reached Juan Fernandez with the
Centurion, the Gloucester, and the Tryal, his united crews of 961 men had
been reduced by that terrible disease to 626, of whom only a small number
were fit for duty; and during last century a Spanish ship was picked up at
sea with all her crew dead from scurvy. Cases of this kind might be
multiplied to show the loss of human life entailed by want of means for
preserving provisions in a fresh state. The cause of the disease was well
enough understood, but a preventive was long sought in vain; and it must
have been a dismal thing for a ship's crew to take their departure on a long
voyage with the thought that few of them would see the end of it.
To such a height did scurvy
attain in the navies and merchant shipping of Britain, France, and other
countries, that the attention of the Governments was seriously roused to the
importance of doing something to remedy the terrible evil. The French
Government took the initiative by offering, in the year 1809, a premium for
the invention of a process for preserving meat, so that it would remain
fresh for any length of time, and in any climate. In the following year, M.
Appert came forward to claim the prize; and, after due investigation, he
received L.480 for the invention of a mode of preserving both animal and
vegetable matter by subjecting them to a certain degree of heat, and then
sealing them up in air-tight vessels. The principle of Appert's system of
preserving was known and practised in this country for years before he was
made famous as the supposed discoverer of it; but those who were acquainted
with the process did not realise its importance, or dream of the application
which he made of it.
Before giving an account of
the modes of preserving provisions now practised, it may be interesting to
note briefly some of the simpler methods of "curing" animal and vegetable
substances which were practised before Appert's time, and are still followed
in -some cases. Heat, moisture, and air are the influences which chiefly
contribute to produce decomposition; and when either of these is got rid of,
under certain conditions both animal and vegetable substances are rendered
proof against putrefaction. When heat is expelled to such a degree that the
juices of flesh and vegetables become frozen, decomposition is impossible.
Meat, fish, eggs, and vegetables may therefore be preserved for any length
of time if they be completely frozen. The remains of animals of a species
believed to have been extinct since the advent of the human race have been
discovered in a state of entire preservation embedded in the ice mountains
of Siberia. It had long been customary to boil and pickle with vinegar the
salmon caught in the Scotch rivers before sending them to London and other
distant places; and a boiling-house was an essential department of the more
remote fishing stations. The late Mr Dempster of Dunnichen, who about the
middle of last century did much to encourage native industry, recommended
the use of ice instead of fire as a preserving medium; and some experiments
were so convincing by their results, that the boiling-houses were abolished
and ice-houses erected. Freezing operates as a preservative by sealing up
the fluids, and preventing their undergoing chemical action. Extracting the
fluids is an equally effective mode of warding off decay. The hot winds
which prevail at certain seasons in many parts of the world have the power
of evaporating with great rapidity the fluids from inanimate bodies; and the
remains of travellers who have succumbed to the scorching blast have been
found years afterwards perfectly dried and free from any trace of
decomposition. The North American Indians prepare the meat which they carry
on their hunting expeditions by removing the fat, cutting the flesh into
stripes, and exposing it to the action of the sun and air, so that it
becomes quite hard, and may be kept for a considerable time without losing
its nutritive properties. This food the Indians call "pemmican." A somewhat
similar process has been tried in South America on a large scale, and
"jerked" beef has within the past few years been sent to this country in
large quantities; but notwithstanding the exceedingly low prices asked,
people have not taken to it kindly. Fish, after being salted to a certain
degree, and dried by exposure to the sun and air, are rendered safe against
decomposition for a considerable time. Many kinds of fruit and vegetables
may be preserved by simply hanging them in a dry place. Another method of
preserving animal and vegetable substances is by excluding the air from
them. Eggs may be protected against decomposition by covering the shells,
which consist of porous earthy matter, with any substance that will
completely shut out the air. A coat of strong spirit varnish will make an
egg keep for years. While some alterations were being made on. a church in
Italy, three eggs were found embedded in the lime of the wall; and though
they had remained in that position for 300 years, they were perfectly fresh,
retaining their natural odour and flavour. The eggs owed their preservation
to the fact that the mortar in which they were embedded prevented contact
with the air. Confectioners in this country preserve eggs for weeks in a
solution of lime. Immersion for a moment in boiling water will also preserve
eggs. By contact with the heat, a film in the albumen in the egg is
coagulated, and so becomes an air-tight envelope within the shell. The
principle of excluding air is that now generally employed in preserving
provisions on a large scale. The efficacy of acid gases in preserving fish
and flesh has been known for many years. The most familiar illustrations of
its use are hams, red herrings, and "Finnan haddies." Wood and turf give off
pyroligneous acid during combustion, and becoming incorporated with the
substance of the fish or flesh, the acid enables it to resist decomposing
influences. Sulphurous acid has at various times been brought into notice as
a preserving agent; and quite recently Dr Dewar of Kirkcaldy has
demonstrated its importance in this respect.
M. Appert claimed to have
discovered—"First, That fire has the peculiar property not only of changing
the combination of the constituent parts of vegetable and animal
productions, but also of retarding, for many years at least, if not of
destroying altogether, the natural tendency of those same products to
decomposition; secondly, That the application of fire in a manner variously
adapted to various substances, after having with the utmost care, and as
completely as possible, deprived them of all contact with the air, effects a
perfect preservation of those same productions with all their natural
qualities." The operations by which fire is made available as a preserving
agent are stated to be—first, enclosing in bottles the substance to be
preserved; secondly, corking the bottles with the utmost care; thirdly,
submitting the enclosed substances for a greater or less length of time to
the action of boiling water in a water-bath; and fourthly, withdrawing the
bottles from the water-bath at the period prescribed. In practice it was
found that in many cases the bottles broke during the boiling process, while
in others the corks were found ineffective for excluding the air; so that a
large proportion of the substances sought to be preserved was lost. Still
the invention was hailed as a great advance towards a much-desired object,
and, as such, was promulgated by the French Government. In 1811 an English
patent was taken out for Appert's process of preservation. The patent was
purchased for L.1000 by Messrs Donkin, Hall, & Gamble, who, in 1812, erected
an extensive preservatory at Bermondsey. It is stated that, after a series
of experiments made by the patentees for the purpose of testing the accuracy
of the process, and ascertaining how far it might be made applicable in a
general way for victualling the maritime service occasionally with fresh
meat, they found that the system of preservation, so far as it had then been
developed, was too defective and uncertain in its results to be made the
vehicle of any safe or profitable commercial enterprise. They then made some
experiments with vessels of tin, and these were so successful that the art
of preserving food was reduced to a certainty. No sooner was the possibility
of preserving provisions demonstrated by this firm, than the ships of the
navy and of the East India Company were supplied with some of the prepared
food; and soon a happy change became apparent in the health of those on
board. Emigrant ships were subsequently ordered to carry certain proportions
of preserved meats, and now no vessel sails on a voyage that is to extend
beyond a few days without having such stores in the lockers. The
meat-preserving trade has assumed large dimensions; and the method adopted
by Messrs Donkin, Hall, & Gamble is that now followed (with certain
modifications in the details of the process) in the great preservatories
which supply the shipping of all nations.
The meat-preserving trade was
introduced into Scotland in 1822, when Messrs John Moir & Son began business
in Aberdeen. There are now nine establishments for the manufacture of
preserved provisions in the country. Of these five are in Aberdeen; and it
may be said that the granite city enjoys a more wide-spread fame for its
preserved meats than it does even for the produce of its quarries— indeed,
it would be difficult to discover a place to which civilisation has
penetrated where the delicacies sent out from the Aberdeen and other Scotch
preservatories are not well and favourably known. The pioneer firm in the
trade was founded by the late Mr John Moir, father of the present senior
partner. The firm began by preserving salmon for exportation, and
subsequently added meats, soups, game, fish, and vegetables. The trade made
slow progress for a time, as public prejudice had to be overcome, and a
market had to be created. Once the thorough efficacy of the mode of
preservation adopted was proved, a demand at home and abroad sprang up, and
new manufactories were erected. Messrs Moir have well maintained their
position in the trade; and their establishment is the largest of the kind in
the country. They have an extensive connection with India, China, and
Australia, and supply a large proportion of the provisions required by
vessels sailing from London, Liverpool, and Glasgow. During the Crimean war
they executed several large contracts for the British and French
Governments. The quantity of preserved meat produced by the firm is about
2,500,000 lb. a-year. They employ a large number of workpeople. Messrs D.
Hogarth & Co. were the second firm in the trade at Aberdeen. They carry on a
considerable business both at Aberdeen and at Deptford. Among the younger
establishments may be mentioned that of Mr Alexander Forbes, Canal Terrace,
which was erected in 1860. Mr Forbes has already acquired a prominent
position in the branch of industry to which he has devoted himself, and is
already favourably known in the home and foreign markets. The other
preservatories in Aberdeen belong respectively to Mr Morton, and to Messrs
Marshall & Co. Besides these there are three firms engaged in salting meat.
Altogether, upwards of 500 persons are employed; and the average annual
value of the preserved provisions manufactured in Aberdeen is about
L.221,000. The business is still increasing, though the only advantage
Aberdeen possesses as a seat of the trade is that of having been the first
town in Scotland and one of the first in Britain that engaged in it. The
other meat-preserving establishments in Scotland are at Leith, Glasgow,
Peterhead, and Burntisland. The last is a small experimental concern.
In 1837 Messrs John Gillon &
Co. established a provision preservatory in Mitchell Street, Leith. From a
small beginning the place was rapidly extended until it became what it still
is—one of the largest establishments of the kind in the country. The
trade-list of the firm contains about 500 varieties of preserved meats,
soups, vegetables, fish, game, &c., and shows the almost unlimited
application of the mode of preservation which is employed. To describe the
processes to which the various kinds of foods are subjected would be a
tedious task, and it will suffice here to note in a general way what may be
seen going on by visitors to the establishment. The preservatory occupies a
large but irregular range of buildings, some of which are three and others
four storeys in height. Almost the whole of the ground floor is devoted to
offices and stores for the completed goods. In the stores hundreds of
thousands of canisters painted of a uniform red are piled in bins. Each
canister bears a label, which, besides indicating the contents, describes
the mode of preparing them for the table. Samples are shown of meats which
have been in the premises for twenty or thirty years; and sonic prepared
milk brought home from the Crimea is to be seen on the shelves. When the
preserving processes are carefully gone through, the only thing that can
affect the articles preserved is damage to the canister. If the canisters
were indestructible the contents would remain good for any number of years.
On ascending to the first floor the first stages of the work of preservation
may be witnessed. A large number of oxen are used weekly, and the carcases
of these are brought in dressed from the public slaughter-houses. The sides
of meat are laid upon benches, and after being divided into pieces of
convenient size have the bones taken out. A selection of the parts is then
made. Certain portions are preserved for roasting, some for boiling, and
others for mincing. The roasting is done in an oven of peculiar
construction, capable of turning out a thousand small roasts at a time. The
roasts are put into tins, with the gravy, have lids soldered upon them, and
are then subjected to the preserving process, which is conducted in the
upper floor. In the preserving-room is a range of oblong iron tanks with
double bottoms. These are partially filled with oil or water, into which the
canisters are lowered on a frame or gridiron. By turning steam into recesses
in the bottoms of the tanks, the contents are heated. After a certain time
the canisters are raised out of the tank, and a small puncture is made in
the lid of each. Through this opening steam flies off with great force,
carrying with it all the air that was enclosed in the case. At a particular
moment, before fresh air has begun to enter the canisters, the apertures are
closed by a drop of solder, and the operation is complete. When the
canisters are raised from the bath the ends are bulged outwards by the
expansion of the air and moisture within; but when they cool, after the
tapping, the ends assume a slightly concave form, owing to the pressure of
the atmosphere. In all cases this is what takes place, whether the articles
preserved be put up in a cooked or in a raw state—the air is driven off by
heat, and shut out by closing the aperture made to allow it to escape.
Essence of beef constitutes what may be called the speciality of the firm.
It is prepared from the first gravy or juice which exudes from the meat in
the process of cooking. Professor Christison thus notes its
peculiarities:—"The meat-juice contains only 6 per cent. of solids. As a
mere nutrient, therefore, it is much in the same category with beef-tea.
Sixteen ounces of beef-tea, made with the contents of one tin, yield only
114 grains of solid extract. It contains no fibrin, no albumen, no gelatine.
It does not even gelatinise, on exposure to the air, for days. It is
ozmazome with the salts and sapid and odorous principles of meat, and
materially different from all boiled extracts. I should add that no good
beef-tea can be made so cheap as with this preserved meat-juice. A tin of
four ounces makes sixteen of strong beef-tea." Mutton and chicken juices are
prepared by the same method as that of beef. Minced meats are cut by a
steam-machine capable of turning out 4 cwt. an hour.
The soups and vegetables are
cooked in a series of huge hem`.- spherical boilers, which are clustered in
the centre of one of the upper rooms. Here, too, the heat is applied in the
form of steam, which is admitted into the double casing of the boilers.
Along one side of the room are arranged eight boilers constructed on the
principle of Papin's digester. They are used to extract the fat and other
nutritive substances from the bones, and the flesh attached to them. These
substances have always been regarded as of high value, and Papin invented
his digester in 1681 for the purpose of extracting them. The fat from the
marrow-bones, under the name of marrow fat, is extensively used for cooking
fish, making stews, pastry, &c.
After the bones are taken out
of the extractors, they are still of some value, and are sent to the bone
mills, from which they come forth as phosphate of lime—a fertilising agent
much used by agriculturists. From the hoofs of the oxen and sheep prussiate
of potash, or hartshoru, is made, but not at the preservatory. Nothing is
lost; but much that would be wasted under the usual domestic modes of
treating food is saved, and turned to profitable account. It is by
economising the material that the prices are so low, and that persons may
obtain, in some cases, the preserved provisions at a cheaper rate than they
require to pay for the same articles in an unprepared state. The term "in
season," as applied to articles of food, may be said to have been abolished
by this meat-preserving process; for there is no delicacy that may not be
had in a perfectly fresh state on any day in the year.
It is unnecessary to go
further into detail so far as the preparation of the various kinds of food
is concerned; but there is one department of the preservatory which merits
notice, as illustrating the effect which machinery of the simplest kind
exercises in saving manual labour. In order to make the tin canisters by the
usual method, more than 100 tinsmiths would be required; but this part of
the work is accomplished by machines worked by men and lads, who can learn
the business perfectly in the course of a few weeks. Messrs Gillon & Co., in
conjunction with an Aberdeen firm, purchased the patent for canister-making
machinery from an American inventor. The sides of the canisters are cut to
any size by a guillotine apparatus, and bent in another machine. The ends
are stamped out, and have their edges raised by dies. Then there are
appliances for soldering the parts together. Many thousands of canisters of
various sizes are thus made weekly, without the aid of regularly bred
tinsmiths.
The ships of some of the
Arctic expeditions were supplied with provisions prepared by Messrs Gillon &
Co., and nearly all the European Governments have at various times received
supplies from them. During the Crimean war their preparations were
extensively used in the hospitals, and on board the war-ships of Britain and
France; and the troops of the Abyssinian expedition were provided with a
considerable quantity. It is a remarkable fact that South America and
Australia are among the best markets for preserved meats, in both of which
countries companies exist for the purpose of preserving beef and mutton for
the European markets. British residents in India depend largely on preserved
provisions for their meals. Scotchmen abroad insist on having haggis at all
their national festivals, and many "chieftains of the pudding race" are sent
out in a preserved state by Messrs Gillon & Co. |
