Improvements in Methods of Preserving Perishable Substances.
Year: 1897

page_text: Date of Application, 16th Nov., 1897-Accepted, 16th Nov., 1898
COMPLETE SPECIFICATION.
Improvements in Methods of Preserving Perishable Substances.
I, WILLARD GIBSON DAY, of 120, East Franklin Street, in the City of Baltimore
and State of Maryland, one of the United States of America, Gentleman, 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 follow-
ing statement:
-
My invention relates to methods of preserving perishable substances through
the action of radiant energy, such as light, heat and actinic waves, developed
by and from an electric current. I have found, and demonstrated after careful
experiment, that the action of the rays from powerful light, such as that pro-
duced by either incandescent or arc electric light on an organic body placed in
proximity to it, is such that all incipient germs of life, whether of approximately
high order (such as life germs, e.g. those of a hen's egg), or of a low order, such
as decay germs, or germs of the kind which cause putrescence and mold, are
killed. In brief, this radiant energy has a sterilizing effect. I therefore con-
sider the application of these rays to be highly important in the art of preserv-
ing perishable food from the influence of mold and decay.
By proximity of the organic body to be acted on to the source of radiant energy
is meant that the substance to be preserved is placed in such intimate nearness
to the centre of energy from which the light, heat and actinic waves proceed, that
said energy is capable of being concentrated on said substance, in order to pro-
duce the desired effect. Therefore, there must be such intimacy of relationship
between the substance and the source of energy as will produce, under all normal
conditions, the effect or an approximation to the effect desired; consequently,
the mere incidental placing of an electric lamp within a room for lighting pur-
poses would not be regarded as resulting in any of the functions accomplished
by my arrangement, and therefore I have no intention of covering such an
incidental arrangement, as such incidental arrangement has no bearing upon
my invention.
The apparatus required for this method is a very simple one, being either an
incandescent or an arc light, placed near said substances, or in a chamber or
receptacle which may hold these substances-they being acted upon either
directly, or through slight intervening media. This lamp is supplied with an
electric current, either alternate or continuous, which is of the necessary voltage
and amperage, such as to bring the light to sufficient intensity to perform its
work. With this arrangement of apparatus, it is preferable to use some form
of regulation, such as an ordinary resistance regulator or rheostat, in case of a
direct current; or inductive resistance in case of an alternating current, so as to

page_text: bring the light to the intensity proper to perform the desired operation upon any
part of the material.
The lamps may be arranged in banks, with reflecting bodies at their backs,
to concentrate the energy upon the substance to be acted on. Moreover, it is of
importance to have a circulation of air passed by and around these substances,
in order to rapidly carry off the moisture; and therefore, it is advisable to arti-
ficially dry said air before it is passed around or through these substances.
Artificially dried air may be passed in currents through these receptacles by means
of an ordinary pumping apparatus, thus passing it along and through the sub-
stances in such a way as to quickly carry off all moisture. It has been found by
me that it is desirable for efficiency of action that the substances be reduced to
such condition that is, made sufficiently thin-that they can be readily and
economically acted on.
Referring to the accompanying drawing, let G, represent a generator of elec-
tricity, either a direct or an alternating current dynamo machine.
Let LL represent wires extending from said generator to an incandescent
lamp A, or to an arc lamp B. Let I and 2, represent, respectively, a receptacle
which the organic perishable substance is placed in
are
and a holder in or on
proximity to the light. As shown in the drawing, various substances
placed in or on this receptacle for instance, meats, fish, eggs, vegetables and
other similar organic substances. R represents a resistance regulator, or rheostat,
or inductive resistance, which is placed anywhere in the circuit between the
source of electrical energy and the lamp. Having raised the potential to the
required degree, and having attained the desired amount of current in the circuit,
we switch the lamp into action and place the substances in or upon the receptacle 1
or 2, and expose them to the continuous action of the rays and heat from the light
for any length of time--say from a few minutes or hours, up to several days-
the period, of course, depending upon the tenacity of life exhibited by each species
of life germs.
It is often the case that the lowest forms of life, such as mold
germs, exhibit the greatest tenacity. Therefore, it is well in such cases to expose
the material to the direct action of the light for, say, several hours, or even days,
as the case may be. Within the receptacle, in which is placed a group of incan-
descent lamps, preferably in banks,
behind or
are reflectors, situated
in proper relation to the lamps, so as to concentrate the rays of light upon
the substances to be treated. Instead of reflectors of the mirror type, white-
painted surfaces may be employed. These mirrors or reflecting surfaces are, how-
ever, not absolutely essential, and may be omitted. An air pump D may supply
a current of ordinary air, or preferably artificially dried air, with a sufficient
impetus to pass by and through the substances and carry off moisture, dust and
other injurious deposits. At D₁ is shown the exit at which the air passes out
of the receptacle. The air may, however, be used under natural draft, induced
by the heat within the receptacle, which, under such conditions, would have
proper means for admission and discharge.
I find that a temperature of about 90° 110° Fah. is that producing the best
results, although I have attained good effects under temperatures somewhat lower
and higher.
I have found this action effective and useful in preserving meats, fish, eggs,
milk, fruits and vegetables; in fact, all organic perishable substances, and liquids
containing germs or microbes.
If an incandescent lamp is used, it is to be clearly understood that the filament
is to be of sufficient capacity to carry the necessary current of the proper
potential. Therefore, it is preferable to have the filament of much higher
capacity than the one in an ordinary incandescent light of, say, 16 to 32 candle
It is much better to use a lamp of, say, from 50 to 100 candle power, or
power.
even more.
It may be necessary, under some conditions and in some climates, when it is
desired to maintain intact the sterilizing action of the radiant energy or actinic

page_text: waves (produced from the incandescent or arc lamp), that the perishable sub-
stances shall be surrounded by a wrapping impervious to decay germs, either after
being acted on by said waves, or while being acted on by said waves, and after. For
though, under certain conditions, the action of these rays would be efficient in
destroying the germs that are present, yet their action might not, under these
conditions, protect the substances from future attacks of germs; therefore, a pro-
tecting coating, under such conditions, is necessary in all cases in which it is
desired to keep the substances any considerable length of time uninjured and
free from the above-mentioned deteriorating influences. The use of such pro-
tecting coating, with substances treated as aforesaid, is therefore recommended
where such conditions require it, and forms part of my invention; or the sub-
stances may be placed in glass jars and immersed in liquid through which the
radiant energy of the light will penetrate and effect the destruction of germs.
For many substancés, a satisfactory germ-proof envelope would consist of a
closed canvas bag coated exteriorly with lime-wash, after the manner of the bags
in which hams are commonly sold; but there are various other materials which
would answer the purpose as well as the one I have designated.
In cases where the substance is placed in a glass jar and surrounded with a
liquid through which the radiant energy of light will pass, the liquid employed
will have to be suited to the substance, and one that will not impair its value
as an article of food. Among the liquids adapted for the purpose, are water, the
edible oils and vinegar.
In the practice of my invention, in treating for instance, meats, I have found
it advisable to reduce the meat to slices or cuts, from half an inch to one inch and
a-half in thickness; and, after treatment, under the conditions hereinbefore
mentioned, has been completed, to pulverize or grind the material so as to bring
it to a convenient condition for packing, shipment and use.
In the use of meat
so treated and pulverized, it has been found that it may be made, by cooking,
into most acceptable dishes for the table, by the use, first, of sufficient moisture
to restore the article to somewhat of its original condition, and afterwards pre-
paring and seasoning it in any way known to the art of cookery. If the meat, or
other substance, is to be used as the basis of a soup, stew, or the like, the previous
addition of water or moisture is obviously unnecessary.
Any of the substances treated under my invention and pulverized, may, if the
form in which they are to be eaten requires it, be, before preparation for the
table, restored to a condition resembling the original one, by the addition of water.
The air admitted to the substances while in the presence of the lamps, may
be filtered by any suitable means, to exclude from the substances the deleterious
matters ordinarily found in the atmosphere, as well as to exclude flies or other
insects, dust, etc., etc. A screen, or filtering agent, suitable for this purpose is
represented by X.
The pulverized material may be conveniently cooked as a solid dish, as follows:
First, supply to a given quantity enough water, or a little more, to restore that
lost by evaporation, and allow the mixture to simmer over a fire for a short time
until it is reduced to a pulp. Then cook, with the proper constituents and season-
ing, as croquettes, hash, Hamburg steak, &c., or in any of the many ways known
to the art of cookery.
Oysters, crabs, clams, &c., in this form of powder, may be deviled or other-
wise dished. The mode of preparation of soups, stews, and the like, will be
evident to the skillful cook.
The product which results from this process differs from all others with which
I am familiar, in being cured without any cooking action, or by the employment
of creosote, smoke, salt or other antiseptic. The application of a powerful electric
light, in accordance with my method, destroys any germs which may have been
within the substance; while the process affects both the exterior and the interior
portions of the substance, so as to prevent the entrance of any germs from the

page_text: outside. The brittleness caused by curing in dry air renders the substance easily
pulverizable at any time after the completion of the process.
I am aware that, heretofore, electric light plants, e.g. arc or incandescent, have
been installed in stores, markets, storage rooms, and the like, and that in such
stores, markets and storage rooms perishable substances have been suspended
or stored. Such an arrangement I do not claim, as having no bearing upon my
invention, which is strictly limited to the bringing of perishable substances, such
as food products, distinctly within the active influence of the waves of radiant
energy which are generated by and through the powerful light, which is in
proximity to said substance. In fact, it is an essential feature of my invention
to have such juxtaposition of light and substances that the operative effect, which
is the gist of my method, can take place. In the proper carrying out of this
method, as has been before set forth, suitable regulation of the intensity of the
waves of radiant energy is an important factor.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The method of preserving organic perishable substances, which consists in
producing waves of radiant energy, bringing said radiant energy to the required
strength and activity, and causing it to penetrate and act upon the perishable
substances placed in proximity to said point of action for a sufficient length of
time to destroy all germs of decay, substantially as set forth.
2. The method of preserving organic perishable substances, which consists in
generating electrical energy, producing by said energy waves of radiant energy,
bringing said radiant energy to the required strength and activity, and causing
it to penetrate and act upon the perishable substances placed in proximity to said
point of action for a sufficient length of time to destroy all germs of decay, sub-
stantially as set forth.
3. The method of preserving organic perishable substances, which consists in
generating electric currents, carrying said currents to any desired point, producing
by said currents light, heat and actinic waves of energy, bringing said waves to
the required strength and activity, and causing them to penetrate and act upon
the perishable substances placed in proximity to said point of action for a
sufficient length of time to destroy all germs of decay, substantially as set forth.
4. The method of preserving organic perishable substances, which consists in a
generating electric currents, carrying said currents to any desired point, producing
by said currents a focus of radiant energy in, for example, an incandescent or
arc lamp, by which light, heat and actinic waves are produced, and causing said
waves to penetrate and act upon the perishable substances placed in proximity
to said focus for a sufficient length of time to destroy all germs of decay, substan- 4
tially as set forth.
5. The herein described method of preserving organic perishable substances
from decay and deterioration, which consists in producing powerful light, heat
and actinic or chemical rays capable of penetrating said substances, and in
proximity exposing the same to the penetrative action of said rays for a sufficient 4
length of time to accomplish the required result.
6. The method herein described of preserving organic perishable substances
from decay and deterioration, which consists in producing powerful light, heat
and actinic or chemical rays capable of penetrating said substances in proximity,
exposing the same to the penetrative action of said rays, and regulating the 5
amount of energy in accordance with the demand, and subjecting said germs to
said action for such time as is in accordance with the strength of the germs to
be destroyed in each particular case.
7. The method of preserving organic perishable substances from decay, which
consists in producing light, heat and actinic or chemical rays capable of penetrat- 5
ing said substances, and in proximity exposing said substances to the penetrative

page_text: action of said rays for a sufficient length of time to accomplish the required result,
and enveloping the said substances in a germ-protecting covering so as to prevent
new access of germs to said substances, substantially as set forth.
8. The method of preserving organic perishable substances, which consists in
generating electric currents, carrying said currents to any desired point, produc-
ing by said currents light, heat and actinic waves of energy, bringing the said
waves to the required strength and activity, and causing them to penetrate and
act upon the perishable substances placed in proximity to said point for a sufficient
length of time to destroy all germs of decay, and subjecting said substances, while
under the influence of said currents, to a circulation of air for carrying off there-
from the moisture liberated by the heat energy of said electric currents, substan-
tially as set forth.
9. The method of preserving organic perishable substances, which consists in
generating electric currents, carrying said currents to any desired point, produc-
ing by said currents light, heat and actinic waves of energy, bringing the said
waves to the required strength and activity, and causing them to penetrate and
act upon the perishable substances for a sufficient length of time to destroy all
germs of decay, and subjecting said substances, while in proximity to, and under
the influence of said currents, to a circulation of artificially dried air for carry-
ing off therefrom the moisture liberated by the heat energy of said electric cur-
rents, substantially as set forth.
10. The method of preserving organic perishable substances, which consists in
generating electric currents, carrying said currents to any desired point, produc-
ing by said currents, light, heat and actinic waves of energy, bringing the said
waves to the required strength and activity, and causing them to penetrate and
act upon the perishable substances for a sufficient length of time to destroy all
germs of decay, and subjecting said substances while in proximity to, and under
the influence of said currents, to a circulation of artificially dried and filtered air
for carrying off therefrom the moisture liberated by the heat energy of said electric
currents, substantially as set forth.
"
11. The herein described method of producing an article of food, which consists
in subjecting the food substance, placed in proximity to the radiant energy of
electric currents, utilizing therefrom the light, heat and actinic waves produced
thereby, and carrying off the moisture liberated by the heat energy of said cur-
rents, substantially as set forth.
12. The method of producing an article of food, which consists in subjecting
the food substance placed in proximity to the radiant energy of electric currents,
utilizing therefrom the light, heat and actinic waves produced thereby. carry-
ing off the moisture liberated by the heat energy of said currents, and finally pul-
verizing or grinding said substances, substances, substantially as set forth.
13. The method of producing an article of food, which consists in subjecting
the food substance placed in proximity to the radiant energy of electric currents,
utilizing therefrom the light, heat and actinic waves produced thereby, carrying
off by artifically dried air the moisture liberated by the heat energy of said
currents, and finally pulverizing or grinding said substance, substantially as set
forth.
14. The method of producing an article of food, which consists in subjecting
the food substance placed in proximity to the radiant energy of electric currents,
utilizing therefrom the light, heat and actinic waves produced thereby, carrying
off by artificially dried and filtered air the moisture liberated by the heat energy
of said currents, and finally pulverizing or grinding said substance, substantially
as set forth.
15. An improved food product composed of an uncooked, unsmoked, unsalted
or chemically unchanged organic substance in which the destructive germs have
been sterilized, and in which the natural juices remain in a quiescent, but un-
changed and utilizable condition, substantially as described.
16. An improved food product composed of an uncooked, unsmoked, unsalted

page_text: or chemically unchanged organic substance in which the destructive germs have
been sterilized, and in which the natural juices remain in a quiescent, but un-
changed and utilizable condition, said product being pulverized, substantially as
described.
13 ..
21
WILLARD GIBSON DAY.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.