Improved Process and Apparatus for Freezing Meat, Alimentary Products, and other Substances.
Year: 1898

page_text: Date of Application, 4th Mar., 1898-Accepted, 16th Apr., 1898
Improved Process and Apparatus for Freezing Meat, Alimentary
Products, and other Substances.
I, HENRI ROUART, of 66, Quai Jemmapes, Paris, in the Republic of France,
Engineer, do hereby declare the nature of this invention and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement :-
The processes at present employed for freezing food products with a view to their
preservation are generally very costly and give rise to serious inconveniences. It is
for this reason that meat and other like articles are placed in vessels immersed in a
non-congealing freezing liquid or in hermetically closed cells immersed in a cold
liquid, or even in chambers having a slow circulation of cold air. Radiation from
cold bodies has also been employed. All these means necessitate, when it is a
question of transportation over long distances, the permanent operation of
refrigerating machines arranged on board the ships or the like, which are both costly
and somewhat uncertain.
My invention consists in directly immersing the substances, such as meat, fish,
butter and other like food products, in a non-congealing liquid refrigerated by some
refrigerating medium. By this operation the external surface of the products which
comes in contact with the cold liquid is frozen and immediately hardens, and then
the congelation rapidly spreads up to the centre. It is needless to state that the
non-congealing liquid is selected in such a way as to exert no deleterious action on
the food substances, for instance a mixture of water and glycerine, water and alcohol,
water and sea salt or the like is employed in suitable proportions to lower the
temperature if need be to 20° Centigrade. The food products thus congealed or frozen
are then withdrawn from the baths and wrapped up for transportation.
The apparatuses for carrying out this process may vary in form and dimensions
according to the nature and quantity of the substances which it is desired to preserve.
Two arrangements of apparatus combined for this object are shown in the accompanying
drawings, in which
Figure 1 is a longitudinal section of a preserving apparatus.
Figure 2 a horizontal section of same;
Figure 3 a transverse section whilst
Figures 4, 5, 6 are respectively longitudinal, horizontal and transverse sections of
a preserving apparatus in which the circulation of the non-congealing freezing liquid
is modified.
In these drawings it is assumed that articles to be preserved are represented by a.
The apparatus shown in Figures 1, 2 and 3 is formed of a wooden chest c closed in
its upper part by a lid having double walls. In the interior of this chest a metal
tank or trough b is placed which is smaller than the chest in length and width.
This trough or tank also rests on the bottom of the chest by means of insulating
supports & and is thus surrounded by a cushion of insulating air.

page_text: through this double bottom and through the trough or tank proper and through the
double walls at the ends in the direction indicated by the arrows.
The articles are kept immersed by means of a grating or hurdle k or any other
suitable means. This grating may preferably have a vertical reciprocating movement
to a small extent which agitates the liquid and facilitates the freezing by renewing
the surfaces in contact.
The arrangement shown in Figures 4, 5, 6 differs from the foregoing one by the
circulation of the non-congealing liquid taking place horizontally instead of
vertically.
The apparatus is in this case also composed of a trough or tank b arranged (with
the same precautions as before) in a chest c, but in this case it is one of the longitudinal
walls which is double and contains the worms e traversed by the refrigerating medium.
The internal wall of this double wall is bored with holes at the ends and the
agitator ƒ produces a circulation of the non-congealing liquid as shown by the
arrows.
When the apparatus hereinbefore described is intended to be employed for
preserving meat and a solution of sea salt is employed as the non-freezing liquid,
things are arranged as shown in the drawing, that is to say the meat is entirely
immersed in the saline solution, the temperature of which is lowered to about
20° Centigrade and which circulates constantly in contact with the substances to be
preserved.
Under the direct action of this liquid the surface of the meat congeals and hardens
immediately and forms a protective casing of very slight thickness which prevents
the salt from penetrating farther into the meat. The freezing is then rapidly
completed up to the centre. The very thin salted layer which may be formed on the
external surface of the meat can have no influence as regards its comestibility but on
the contrary during long continued preservation serves for preventing the surface
mould which is frequently produced in this kind of preservation. The meat thus
frozen or congealed is withdrawn from the bath and when it is to be transported is
stored in well insulated cases. Usually the very low temperature to which the meat
has been subjected and the good insulation of the cases will suffice for always main-
taining the meat at a temperature below 4° Centigrade; in other cases, for instance
for long voyages, refrigerating apparatus may be employed as an auxiliary means but
of course these may be of small dimensions, or the meat may be kept in cold air
or in a non-congealing bath of sea salt for instance maintained at a temperature of
4° Centigrade.
An excellent congelation may also be obtained by placing the substance to be
preserved directly into a refrigerating mixture, for instance in ice powdered in suitable
proportions with sea salt. The melting of the ice and salt forms a non-congealing
very cold liquid which solves the question.
The process of preservation hereinbefore described for meat may also be employed
for other food products, such as game, fish, butter, eggs and the like and to organic
substances in general. The only modifications in the apparatus required therefor
will be in the means employed for keeping these articles submerged.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. A process for preserving alimentary and other like organic substances, which
consists in immersing the said substances in a suitable non-congealing liquid
circulating in contact with them and maintained at a low temperature by a
refrigerating apparatus, with the object of forming on the surface of the said substances
a protective layer or casing and of enabling them when congealed or frozen to the
centre to be transported, substantially as herein before set forth.
2. An apparatus for carrying out the herein described process for preserving
alimentary and other organic substances, which consists of a chest (c), a trough (b)
with double bottom and double ends placed within said chest and filled with a non-

page_text: freezing liquid, and a grating or hurdle (k) arranged to keep immersed the substances
to be preserved, in combination with coils e cooling the liquid and an agitator (f)
insuring its continuous circulation, substantially as hereinbefore described with
reference to Figures 1, 2 and 3 of the accompanying drawings.
3. An apparatus for carrying out the herein described process for preserving
alimentary and other organic substances, which consists of a chest (c), a tank or
trough (6) placed within said chest and having one of the longitudinal walls formed
double, said tank being filled with a non-congealing liquid, and a grating or hurdle (k)
arranged to keep immersed the substances to be preserved, in combination with coils (e)
cooling the liquid and an agitator (f) insuring the continuous circulation of said
liquid, substantially as herein before described with reference to Figures 4, 5 and 6 of
the accompanying drawings.
D
1 1000
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant.