An Improved Process for the Sterilization of Milk.
Year: 1892

page_text: Date of Application, 3rd Dec., 1892
Complete Specification Left, 2nd Sept., 1893-Accepted, 7th Oct., 1893
PROVISIONAL SPECIFICATION.
An Improved Process for the Sterilization of Milk.
I, GUSTAVE CHARLES LEGAY, of 21, Boulevard St. Jacques, Lille, Nord, in
the Republic of France, Doctor, do hereby declare the nature of this invention to
be as follows:-
My invention relates more especially to an improved process by which milk can
be sterilized and rendered perfectly safe and wholesome, in every household.
I take a bottle of glass or other suitable material which I fill with the milk at the
ordinary temperature (about 15 degrees C.), and I then cork the vessel. It is then
immersed in a hot water bath and as the milk becomes warm it expands and rises
in the neck of the bottle until it reaches a horizontal mark made upon the side of
the latter. When it has reached this point the temperature of the milk is known
and is such that it is completely sterilized. The mark on the bottle has in fact
been determined so that when the milk reaches it it has a temperature of
85 degrees, which destroys the microbes from which danger might arise when the
milk is used.
Another result of this expansion of the milk is that the air is compressed into
the upper part of the neck of the bottle, its pressure being increased upon the
surface of the milk as the latter becomes hot and approaches to the degree of
sterilization (85 degrees).
The advantage of the improved process consists first, of the indication of the milk
Second, the
itself when the temperature of sterilization has been reached.
production of pressure upon the surface of the milk by the compression of the air
above it caused by the expansion of the milk.
Of course the bottle or vessel must in the first place always be filled with milk to
the same height as indicated by a second mark upon the neck.
The application of the invention may be varied more or less according to the
form of the bottle, the material of which it is composed, the arrangement of the
cork or stopper, and of the neck and other parts of the bottle, all of which may be
varied more or less as may be found advisable.
Dated this 3rd day of December 1892.
EDWARDS & Co.,
35, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved Process for the Sterilization of Milk.
I, GUSTAVE CHARLES LEGAY, of 21 Boulevard St. Jacques, Lille, Nord, in
the Republic of France, Doctor, 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 and accompanying drawing, that is to
Bay :-
The utility of sterilized milk is recognised by all hygienists and doctors, especially
by those who are interested in the food of infants.
Raw milk may contain the germs of different tuberculous and other diseases,
whilst by being boiled it loses a certain part of its nutritive principles. It should
therefore be neither taken raw nor boiled.
Sterilized milk gets rid of both these objections. It consists of milk raised to
such a temperature that the morbid germs cannot live in it. This temperature of
sterilization should be obtained under pressure, so as to prevent the disengagement

page_text: of gases as the temperature rises, the carbonates which are of value for nutrition
especially for infants being decomposed.
The manufacture of sterilized milk delivered in closed bottles to the consumer is
already of some importance, but the great cost of this product, however, renders it
inaccessible to the middle and poorer classes who are most interested.
It is necessary therefore in order that the use of sterilized milk may become
common, to provide the public with a convenient domestic apparatus, of which the
size, shape, and material, may be varied, but the construction of which depends
upon the very simple system which constitutes the subject of my invention.
This consists substantially of placing in the vessel milk at the ordinary tempera-
ture (about 15° C.) closing the vessel, and then placing it in a water bath. As the
milk becomes hot it expands and rises in the neck of the bottle until it reaches a
horizontal mark previously made upon the latter. At this moment the temperature
of the milk is known, and is such that the milk has become sterilized. In practice,
the position of the mark is determined so that the milk only reaches it at a
temperature of 85 degrees, which the microbes, dangerous when milk is used as food,
are unable to resist.
Another result of the expansion of the milk is that the air is pressed back into
the neck of the vessel, its pressure being increased as the milk becomes warm, until
it reaches the stage of sterilization (85°).
The process consists therefore first, of an indication by the milk itself when the
sterilizing temperature has been reached, and second, the production of pressure on
the surface of the milk by forcing back the air in the neck of the vessel as the milk
expands.
The method of applying this system may be varied more or less as regards the
shape of the vessel, its materials, and the arrangement of the stopper, neck, and
other parts, and I do not confine myself to the particular form or proportions of the
parts.
In the accompanying drawing, two somewhat different modifications of the
apparatus are shewn.
Figure consists of two parts. First, a globular glass vessel A of known
capacity. A first horizontal mark D near the junction of the neck C bears the
figure 15°. A second similar mark upon the neck somewhat above the first, and
marked B, indicates 85°. These two lines have been so determined in their position
that milk introduced into the vessel A. at 15° up to the lower mark D, will reach
the upper mark B when it has attained the temperature of 85°.
The dimensions of the neck C are so calculated that at 85° a pressure of 30 to
40 centimetres of mercury is produced upon the surface of the expanded milk.
Second, a support E provided with a spring rod F serving both to support the
vessel A and to hold firmly upon the neck C a stopper G of glass made tight by
means of an india rubber ring H, the whole forming a spring stand.
A metal ring E which may be notched at different parts of its edge supports the
base of the globular vessel. From this ring, or from a projection soldered to it,
rises vertically a steel rod F curved over at its upper end so that it enters either an
opening at the top of the stopper G, or a notch in the top of the latter.
In the first case the stopper is permanently attached to the rod whilst in the
latter they are distinct. In either case the elasticity of the steel rod serves to
ensure the tight closing of the vessel.
In order to use the apparatus, milk at the ordinary temperature is first poured
into the vessel up to the mark 15°; the vessel is then closed and the stopper fixed
by the spring, and the whole is introduced into a water bath. Finally the vessel
and its support are withdrawn when the milk has reached the mark 85°.
The milk when withdrawn from the vessel is deprived of the morbid germs which
it may have contained, of those at least which are capable of communicating to
children and others tuberculosis, (which is most to be feared) and a certain number
of other febrile affections, capable of transmission from the animals giving the milk,
to man.

page_text: The second modification, illustrated in Figure 2, is based upon the same principle
and resembles in shape a tea-pot without a spout. The vessel I is of porcelain,
earthenware, or tin plate, provided with a handle J and with feet O to keep it from
touching the bottom of the bath. The upper part is contracted to form a neck, and
is arranged to receive a glass stopper K, 6 to 8 centimêtres high, hollow and
resembling an inverted test tube. The stopper is fixed upon the neck by a bayonet
joint, the joint being made tight by an india rubber ring L. Upon the side of the
tube is made a horizontal mark M, marked 85°.
The vessel is filled with milk at 15° up to the top of the neck, and the stopper
then fixed in its place.
is
The apparatus is placed in a hot water bath and heated until the milk reaches
the mark 85°, when as already explained in the modification already described, the
desired result is obtained, the milk having been brought under pressure to 85° and
thus sterilized.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
A close vessel in which the liquid to be sterilized is heated, such vessel itself
indicating the required temperature, at which a determined pressure is produced upon
the liquid by the expansion of the latter, substantially as and for the purpose
described and illustrated.
1002
ed this 2nd day of September
1902
EDWARDS & Co.,
35, Southampton Buildings, London, Agents for the Applicant.