An Improved Method of and Apparatus for Preserving Milk.
Year: 1895

page_text: Date of Application, 22nd Nov., 1895-Accepted, 25th Jan., 1896
COMPLETE SPECIFICATION.
An Improved Method of and Apparatus for Preserving Milk.
I, AURELIO FERNÁNDEZ JARA, of 125 Calle de la Catedral, Santiago Chili,
South America, Agriculturalist, 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 :-
My invention relates to a method of and apparatus for preserving cows' milk in
its natural state, and sterilizing it without changing its organoleptic properties,
and without the addition thereto of any substance or substances whatsoever.
I have heretofore attempted to preserve milk by adding to it some specifically
prepared gas, but without success; for having experimented with various gases, I
found that they were all valueless for the preservation of the milk, in that they
were absorbed by the milk with great rapidity. This was especially the case with
oxygen. Milk possesses great absorbing qualities, and as it issues from the cow's
teat in the form of thin thread-like streams and passes through the air, which is
loaded with deleterious gases, and injurious floating matter it necessarily absorbs a
great quantity of these substances and becomes saturated with them, largely on
account of the thin and divided form in which it comes from the teat. Besides
these deleterious gases natural organic extraneous matters, such as hairs and pus
are liable to become mixed with the milk, and these impurities if not removed
render the liquid of such character that it is readily modified and changed by the
influence of external agencies.
In the practice of my invention, I have succeeded in extracting and removing
from the milk the air, gases and extraneous matter, thus rendering the milk ready
to be preserved in its natural state. This I do by first passing the milk through a
suitable filter, whereby I deprive it of all organic and solid impurities. The milk
is then drawn from the filter to a vacuum chamber, which it enters in the form
of a fine spray. In this operation the deleterious gases separate from the milk
(which they will do in a partial vacuum by reason of their lighter specific gravity)
and leave the milk perfectly pure and free from all substances that would cause
fermentation or separation of its component parts.
The milk having been treated as above described, and being now in a perfectly
pure and natural state, it is necessary, in order to prevent the separation of the
cream, to form a homogeneous liquid or stable emulsion. For this purpose the
milk is heated to a temperature of about 90 to 100 degrees Centigrade, and
thereafter rapidly cooled to 0 degrees Centigrade. This must be done very quickly
in order to preserve the caseine in an albuminous state. While in that condition,
that is to say, before it returns to its normal state, the milk is placed in the cans
and sealed. In this manner, the caseine is prevented from suffering chemically,
and the fat is not allowed to rise.
The air and gases contained in milk under ordinary circumstances, when allowed
to remain at rest, rise to the surface of the liquid because of their lightness, and
carry with them the greasy cellules, which, on coming together, form creani. By
my process the gases are extracted without harm to the milk.
Since the cans are filled completely with milk while the latter occupies its least

page_text: volume, corresponding to the temperature 0 degrees Centigrade, it follows that after
the milk returns to the normal or atmospheric temperature, it will increase in
volume and entirely fill the can under great pressure.
The can in which the milk is finally packed or stored is of peculiar construction,
in that it is very shallow as compared with its diameter; the object of such con-
struction is to diminish the force of asceusion or tendency of the lighter constituents
of the milk to come to the top; should there orcur such a separation, and should
part of the cream come to the top, the coating of cream so formed would be
exceptionally thin. In no case can there be any material separation of the cream,
if the milk is well prepared and the can is well filled. But should there be a very
small separation of cream, there could be no formation of butter, because of the
absence of air, and cousequently no churning would be possible.
When the cans of milk are full and well soldered, the milk can be sterilized by
subjecting it to a temperature of 113 degrees Centigrade for 20 minutes, or
118 degrees Centigrade for 15 minutes, or 120 degrees Centigrade for 10 minutes,
without suffering any alteration in colour or taste.
Having thus in a general manner described my process of preserving milk, I
will now describe an apparatus that may be used for carrying out the process
reference being had to the accompanying drawings, in which
Figure 1 is a side elevation of the apparatus, one of the purifying cylinders
being removed and
Figure 2 is a plan view thereof with a part broken away.
Figure 3 is an end elevation of the same on a larger scale one of the vacuum
chambers being shown in section.
Figure 4 is a vertical section also on a larger scale of the heating cylinder or
pasteurizer, and
Figure 5 is a cross section of the same.
Figure 6 is a vertical longitudinal section of the refrigerator and accumulator.
Figure 7 is a front elevation of part of a truck, on which the cans to be filled
are mounted, and
Figure 8 is a side elevation of one series of cans.
From
Similar letters of reference indicate similar parts throughout the drawings.
A. represents a tank made of tinned copper, having a capacity of from two
thousand to three thousand litres. In the upper portion thereof, I place a charcoal
filter B, on the top of which the milk is poured when brought from the cow.
the side of the tank B, below the filter, a pipe a extends. To the inner end of
this pipe is attached a rubber tube a', extending downwardly to near the bottom
of the tank A, where it is enlarged. Within this enlarged mouth, sponges are
packed to remove from the milk all traces of charcoal that may have been carried
with the milk through the filter. The pipe a extends from the tank A to the
purifier.
The purifier is composed of two cylinders, 1 and 2, Figures 1, 2 and 3, made
preferably of cast-iron, and lined interiorly with bronze of say inch thick. The
dimensions of these cylinders are substantially as follows: interior diameter
0.30 metres, and height 2.20 metres. These cylinders are placed vertically, and
are separated a distance of about 1.20 metres from centre to centre. The lower
end of each cylinder is hermetically closed by a cover which has in its centre an
aperture of say two inches in diameter, which communicates with a valve
chamber 3 containing a ball valve. The outlet of the said valve chamber of the
cylinder 2 communicates by a pipe 4 of tinned copper with a heating cylinder, or
what I term a pasteurizer G, Figures 1 and 2. The similar valve chamber of the
cylinder 1, communicates with a pipe leading to the external air for the exit of
the gases. The two cylinders 1 and 2 are united by a pipe 5, provided with a
valve 6. The pipe 5 is conveniently arranged at a height of about 1.40 metres
above the lower ends of the cylinders, and the internal diameter of the said pipe 5
and of the pipe 4 is advantageously about two inches.
Within each cylinder 1, 2, is a piston 7, preferably of cast-iron with bronze
°

page_text: packing rings, nicely adjusted to the cylinder in such a way as to be fluid tight.
The said piston of each cylinder is attached to a screw threaded rod 8, which
passes through a screw threaded nut secured to or forming a part of a bevel
pinion 9. Each of the wheels 9 is rotated by means of a bevel pinion 10 upon a
shaft 11, on which shaft are three pulleys 12, 13 and 14. The pulleys 12 and 14
are loose, while the pulley 13 is fixed to the shaft. The pulleys 12 carry cross
belts, and the pulleys 14 straight belts. By this arrangement, I am enabled to
move the pistons 7 in either direction by shifting the appropriate belts from either
the loose pulleys 12 or 14 to the fixed pulleys 13.
The pipe a, as has hereinbefore been stated, extends from the tank A to the
purifier 2, which it enters at about 0-20 metres above the level of the pipe 5. The
mouth of this pipe a, where it enters the purifier 2, is provided with a suitable
spraying device, the object of which is to divide the milk into very fine drops for
the purpose hereinafter explained.
The said
The heating cylinder, or pasteurizer, consists of a vertical cylinder G (Figures 1
and 2) and seen in detail in Figures 4 and 5, say of 1.20 metres in diameter and
3 metres in height, and provided at the top with an adjustable cover.
cylinder contains a coil of tinned copper pipe 15, which serves for pasteurizing by
the aid of steam, with or without pressure. Steam from a suitable source of supply,
enters through the pipe 16 at or near the bottom of the cylinder, the entrance of
the steam being controlled by a valve 17.
Besides the steam coil, the pasteurizer has a series of coils of thin copper pipe 18,
of say one-half inch in internal diameter, which pipes are placed in several series
of concentric circles. In Figures 4 and 5, only two series are shown, but in
practice there are usually five.
The series of coils may be conveniently composed of 16 different pipes wound spirally,
and of a total length of say 814 metres, which will hold 100 litres of milk. The
spiral pipes come together near the upper part of the pasteurizer and communicate
with the valve of the pipe 4, which leads from the purifier 2. The lower ends of
these pipes come together in a similar manner, and open into the pipe 19 near the
bottom of the pasteurizer, which pipe communicates with the refrigerating
apparatus. The object of dividing the milk, which enters through the pipe 4,
into so many smaller pipes is to cause the milk to circulate through the pasteurizer
in thin streams, so that it may be rapidly and uniformly heated.
an
The refrigerator and accumulator 20, shown in Figures 1, 2 and 6, comprise a
tank built conveniently of brick, lined internally with any suitable material, and
having a length of say 2 metres, a width of 1-20 metres and a height or 1.30 metres.
Within this tank is the congealing apparatus 21 of an ice machine, and
accumulator 22. The congealing apparatus has an ellipsoidal pipe coil of tinned
copper, arranged in spirals, which diverge from the end of the tube 19 in a manner
similar to that described with reference to the pasteurizer G. The tubes of this
coil pass from the congealing apparatus 21 to form another coil, which encircles
the accumulator, and, converges at the bottom of the tank, where it is connected
to a pipe 23, which enters the bottom of the accumulator through an opening 24.
The total length of the tubes in the two coils is about 840 metres, and their purpose
is to produce the quick cooling of the milk.
The tank beforementioned is filled with salt water kept in circulation by an
agitator 25, the shaft of which passes out through the tank, and 15 provided with
a pulley 26, driven by a belt.
The accumulator 22 consists of a cast-iron cylinder, open at the top, with an
interior lining of bronze, and having an inside diameter of say 1.30 metres, and a
height of 2-80 metres. Its cubical contents are about 3,000 litres.
Within the accumulator is a cast-iron piston 26, with bronze packing rings,
adjusted in such a way that it may be lifted by the pressure of the milk as it enters
the accumulator. A pipe 27 leads from the bottom of the cylinder outward
through the tank to a second pipe 28, to which are attached two pumps 29, 29.
Pipes 30 lead from these pumps to the can-filling devices, now to be described.

page_text: The can-filling device is shown in Figure 7, wherein 31 represents a frame
mounted on truck wheels, in which frame are placed the cans to be filled, in
vertical series of five cans, connected by small tubes one with the other. The
pipe 32, on the bottom of the truck, receives the milk through the pipe 30 from
the pumps 29. In the pipe 32 is a valve 33, which serves to regulate the admission
of the milk as it comes from the pumps 29, heretofore described. A steam pipe 34,
provided with a valve 35, enters the pipe 32 at a point behind the valve 33. A
number of short tubes 36 project from the upper surface of the pipe 32, and are
connected by india rubber tubes 37, with short tubes, one extending from the
lower can of each series of cans. From the uppermost can of each series, a short
tube projects and is connected by an india rubber tube 39 with a tube depending
from a pipe 38. A short section of glass tubing is introduced in the said india
rubber tube 39 for the purpose of ascertaining when the cans are full.
The cans are made of tin, circular in shape, 16 centimetres in diameter and
47 millimetres high, holding 1,000 grammes of milk. This form presents four
advantages: Firstly, economy of manufacture: one sheet of tin, 14 by 20 inches,
will make two cans, leaving sufficient tin to bind the boxes which contain a dozen
sterilization
cans. Secondly, the cans can be filled with great rapidity. Thirdly,
is very effectively and uniformly accomplished in them. And, lastly, the diameter
is so great in proportion to the height, that the fat globules, have less tendency to
ascend than would be the case with a can of small relative diameter in proportion
to its height.
The cans are united one with the other, in series of five, in the direction of their
diameters, by means of short tubes. They are placed on the truck in skeleton
frames until 20 frames of five cans each have been placed on each side of the car
or truck, which thus holds 200 cans.
The operation is as follows:
Milk from the cow is poured into the upper part of the tank A upon the charcoal
filter B, through which it passes to the bottom of the tank. Passing thus through
the filter, the milk, which may contain many impurities, such as deleterious gases,
dust, pus, hair, etc., is purified, and the organic and other foreign bodies are
removed. From the tank A, the milk passes to the purifier 2, where it is deprived
of the deleterious gases and rendered perfectly pure.
At the beginning of the operation, the piston 7 is at the bottom of the purifier 2.
The valve 6 in the pipe a is closed, as is also the valve 6 in the pipe 5. Through
the medium of a suitable driving belt on the pulley 13, the pinion 9 is rotated in
the proper direction to raise the piston 7 to the top of the purifier, thus creating
within the purifier a nearly perfect vacuum. At the same time that the piston in
the purifier 2 is rising, the piston in the purifier 1 is descending. When the piston 7
reaches the top of the purifier 2, the valve b is opened, and the pressure of the
external atmosphere then forces the milk through the filter B into the tank A, and
from said tank through the secondary filter in the mouth of the rubber tube a and
The
tube a, into the purifier, passing through a meter b' introduced in the pipe a.
mouth of the pipe a, as has been above stated, is provided with a spraying device,
the purpose of which is to break up the milk into exceedingly fine drops, which
fall to the bottom of the purifier. This breaking up of the milk allows all impure
gases to escape, and these being lighter than the milk, will naturally rise to the
top of the purifier. Were the milk introduced in bulk, the gases could not escape
so readily and a portion thereof would remain within the milk, thus defeating the
object of my invention. The milk is allowed to enter the purifier until the meter 6
registers 100 litres. The valve b in the pipe a is then closed, and the valve 6 in
the pipe 5 is opened. The milk will then be on a level with the pipe 5, the gases
being between the milk and the bottom of the piston. The driving belts are now
shifted, and the piston 7 in the purifier 2 is forced downward; the piston in
purifier 1 at the same time rises. The downward movement of the piston 7 of the
cylinder 2 forces the gases through the pipe 5 into the cylinder 1, the piston of
which is rising at this time; and, because of the vacuum created in said cylinder,

page_text: con-
the gas will pass into it with great rapidity. The piston of the cylinder
tinuing its downward movement after the gases have been expelled, forces the
milk through the pipe 4 at the bottom of cylinder 2, into the pasteurizer, the valve
in said pipe having been previously opened. The milk, entering the pasteurizer
through the pipe 4, is divided, and enters the small tubes passing around the steam
coils, and is therein heated to a temperature of 100 degrees Centigrade. The coils
in the pasteurizer hold 100 litres, being of the same capacity as those in the purifier.
The milk remains within the coils about 7 or 8 minutes, which is the time consumed
in the operation of purification. Another body of 100 litres of milk is meanwhile
prepared in the purifier 2, and then forced into the pasteurizer whereby the
previous charge of milk in the pasteurizer is driven into the refrigerating apparatus,
wherein it is cooled to a temperature of 0 degrees Centigrade. Thence it is
forced into the accumulator by another charge of milk, which, having been
purified, is advanced by the descent of the piston in the cylinder 2.
It may be here stated, that the piston 7 in the cylinder 2 is the only means used
to move the milk from the filter to the accumulator. Before entering the
accumulator, the milk passes through a series of coils of small pipe which surround
the same, and enters it through the pipe 23, where it remains until drawn off to be
canned.
All
When a truck has been loaded to its full capacity, that is to say, 200 cans, the
rubber tubes 37 are connected with the small tubes projecting from the bottoms of
the lower cans of the series, and the rubber tubes 39 are connected with the small
tubes at the tops of the series. Steam is then admitted through the pipe 34, by
opening the valve 35. This steam, passing up through the cans, makes its exit
through the pipe 38 provided with any well known form of aspirator. This action
is continued until the cans attain a certain degree of heat, after which the steam
valve 35 is closed and the milk valve 33 opened. The pumps 29 are then set in
operation to drive the milk from the accumulator and to force it through the
pipes 30 into the pipe 32, from which it passes into the cans through the small pipes
and connecting tubes, hereinbefore described. The pumping is continued until the
milk has filled all of the cans and may be seen in the glass tube above them.
the tubes projecting from the tops of the cans are then closed, by pinching or
otherwise, and the pumps again worked, so as to introduce more milk under pressure,
after which the tubes at the bottom are closed. As soon as the cans are full, the
rubber tubes are taken off, and the connecting tubes between the cans are pinched
tight, separated and soldered. The cans of milk are then ready to be sterilized.
By this process of filling, 200 cans can be filled in three minutes by six operators.
To sterilize the milk, the cans are placed on grids of iron in an auto-clave
apparatus, which is well known to all skilled in the art. There they are heated to
a temperature of 113 degrees Centigrade for 20 minutes, or 118 degrees Centigrade
for 15 minutes, or 120 degrees Centigrade for 10 minutes, this being sufficient to
sterilize the milk. The cans are then taken out and placed in a receptacle containing
an agitator to keep the water continually moving around them. Here they are
left for, say, 24 hours, in order that the gases and substances separated by heating
may again recombine. The milk so sterilized preserves its natural colour and
taste, and since there are no deleterious gases dissolved in the milk, nor air in
contact with it, the oxidation of the caseine and lactate is impossible, and the milk
will, therefore, preserve its chemical composition. Nor will there be any precipitation
of the phosphates, as the carbonates and bi-carbonates are in their normal state,
and the full quantity of carbonic acid is present. In the process of sterilization,
the carbonic acid is separated, but, by the rapid cooling, it re-combines with the
separated constituents and again forms carbonates and bi-carbonates.
A machine of the size above described will prepare 10,000 litres of milk daily.
I wish it to be understood that I do not confine myself to the various dimensions
and capacities hereinabove mentioned, as such are given merely by way of
example, and they may be varied if desired without departing from the nature of
my invention.

page_text: 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. In a process for preserving milk, first, extracting from the milk all deleterious
gases and other foreign matter, then quickly raising the temperature to 90
or 100 degrees Centigrade for a short period; and then reducing the temperature
quickly to 0 degrees Centigrade, all without exposure to the atmosphere,
substantially as set forth.
2. In a process for preserving milk, first, extracting from the milk all deleterious
gases and other foreign matter; secondly, quickly raising the temperature to 90
or 100 degrees Centigrade for a short period; thirdly, quickly reducing the
temperature to 0 degrees Centigrade; and, fourthly, introducing the milk into cans,
all without exposure to the atmosphere, substantially as set forth.
3. In a process for preserving and sterilizing milk, first, purifying the milk, then,
raising its temperature quickly for a short period to 90 or 100 degrees Centigrade;
afterwards reducing the temperature quickly to 0 degrees Centigrade; then, filling
the cans with the milk under pressure; and, finally, sterilizing the milk in the cans
by heat and cold, all without exposing the milk to the atmosphere, substantially as
set forth.
4. In a process for preserving and sterilizing milk, first filtering the milk through
charcoal, or other suitable substance, to remove all the deleterious organic matter
and some of the gaseous substance; then, dividing the milk into very fiue streams
in vacuo, to separate the gases from the milk; then quickly removing the gases
from its surface to prevent re-absorption; then raising the temperature quickly
to 90 or 100 degrees Centigrade for about eight minutes; next reducing the
temperature quickly to 0 degrees Centigrade; next forcing the milk under pressure
into cans; and, finally sterilizing it by raising the temperature to say 113 degrees
Centigrade for about twenty minutes, and afterwards reducing the temperature
to 0 degrees Centigrade for about twenty-four hours, all without exposing the milk
to the atmosphere, substantially as set forth.
5. In an apparatus for preserving milk, the combination of a purifier for
separating the milk from its impurities, a heating cylinder, and a refrigerating
apparatus, whereby milk is prepared for canning without exposure to the atmosphere,
substantially as shown and described.
6. In an apparatus for preserving milk, the combination of a filter and tank, a
vacuum cylinder connected therewith, a heating cylinder or pasteurizer connected
to the vacuum cylinder, and a refrigerating apparatus and accumulator connected
to the pasteurizer, substantially as shown and described.
7. In an apparatus for preserving milk, the combination of a filter, a purifier, a
pasteurizer, a refrigerating apparatus, an accumulator, and a can filling device
connected therewith, substantially as shown and described.
8. In an apparatus for preserving milk, a purifier consisting of a tank A, filter B,
and a valved connecting pipe a, provided with a secondary filter, in combination
with vacuum cylinders 1, 2, with a suitable outlet tube 5, a valve 6, and
pistons 7, substantially as shown and described.
9. In an apparatus for preserving milk, the combination of two vacuum cylinders,
pistons within the cylinders, means for operating the pistons in opposite directions,
a valved pipe connecting the cylinders, and a device for spraying the milk as it
enters the cylinders, substantially as shown and described.
10. In an apparatus for preserving milk, the combination, in a pipe for conveying
milk, of one or more sections subdivided into numerous smaller pipes, the combined
carrying capacity of which is equal to that of the larger pipe, substantially as shown
and described.
11. In an apparatus for preserving milk, the combination, in a pipe for conveying
milk, of one or more sections subdivided into numerous smaller pipes, coiled in two
or more series, in which the carrying capacity of all of the smaller pipes is equal to
that of the larger pipe, substantially as shown and described.

page_text: 12. In an apparatus for preserving milk, the combination of an accumulator, a
filling pipe, a pump between the accumulator and the filling pipe, tubes from the
filling pipe to the cans, and tubes provided with gauge glasses from the cans to an
aspirator pipe, substantially as shown and described.
13. The apparatus for preserving milk, substantially as herein shown and
described.
Dated this 22nd dar of November 1905
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.