Improvement in Process of Malting.
Year: 1893

page_text: Date of Application, 27th June, 1893-Accepted, 5th Aug., 1893
COMPLETE SPECIFICATION.
Improvement in Process of Malting.
I, JAMES ADDISON TILDEN, Engineer, of Hyde Park, in the County of
Norfolk, and State of Massachusetts, United States of America, 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 process of malting whereby grain, commonly barley,
is converted into malt without hand manipulation and without transferring the
grain from one place to another during the entire process of conversion.
In converting grain to malt as now commonly practiced there are five distinct
stages, namely, steeping, which consists in soaking the grain in water to impart
to it sufficient moisture to insure perfect germination; second, couching or
removing the excess of water and subjecting the steeped grain to its own heating
action while lying in a quiescent mass until the growing point of the rootlet
begins to show; third, germinating or subjecting the grain to the influence of
very moist air, and intermittingly agitating the same, under which conditions
the grain sprouts or grows until the acrospire and rootlet have reached the
desired development; fourth, withering or stopping the germination by removing
the excess of moisture, thus causing the rootlets to wither or shrivel up; and
finally, kiln drying or driving off all the moisture so as to dry thoroughly and
cure the grain. Incident to this stage the rootlets become detached and the grain
is bleached, making the same white and salable.
This process as now commonly practiced requires for its different stages separate
treatment and handling, and the removal of the grain from one place to another,
and although apparatus has been devised for performing a portion of the series of
operations without separate handling or removal of the grain, and such apparatus
with some modifications and additions can be used in carrying out the process
forming the subject of this invention, the present process is not limited to the use
of any special apparatus.
Suggestions have been made pointing towards the production of malt from grain
by a continuous process in a single apparatus, but the method of treatment suggested
is not capable of producing the desired result, and so far as I am aware a continuous
process of malting has never been successfully practiced.
In carrying out the process of malting in accordance with this invention, the
grain is introduced into a receptacle in which it may be properly agitated and
subjected to the various atmospheric conditions necessary for carrying out the
process, apparatus for comprising such a receptacle and the means for producing the
required atmospheric and agitating conditions being indicated in the drawings
accompanying this Specification and which form part of the Specification in
explaining the process.
Fig. 1 represents a view in elevation of a perforated malting drum arranged to
be rotated upon trucks or carriages, and having ducts or passages provided with
dampers for admitting the required currents of air to the interior of the drum to be
distributed through the mass of grain.
Fig. 2 represents an end view of the same.
Fig. 3 represents a horizontal sectional view of the same.
Fig. 4 represents a cross section through the same.
Fig. 5 represents a sectional view of a malting apparatus of different construction,
comprising a vat having a travelling agitator composed of a ser.es of revolving
screws which are moved back and forth upon carriages through the mass of grain,
ducts or passages being arranged to conduct the required currents of air to an open

page_text: space underneath the vat and through a perforated bottom, thereby distributing it
through the mass of grain.
Fig. 6 is a plan view of the same.
A suitable receptacle for containing and operating upon the grain in carrying
out this invention may be composed of a horizontal perforated drum 1, five to seven
feet in diameter, and an inner concentric drum 2, also perforated, of about one-third
that diameter, the annular space between the drums being closed at the ends by
perforated plates so that an annular cylindrical space is wholly enclosed by
perforated or foraminous walls, in which space the grain to be treated is
introduced.
Means are provided for rotating the drum at variable speeds about its axis which
should be substantially horizontal, and which consists of a gear 3 secured to the
drum, which is driven by the worm 4, ducts or passages 5, 6 & 7 having dampers
for admitting currents of air of the requisite variety of conditions as to temperature
and humidity to pass through the annular body of grain, said currents being
commonly introduced into the interior of the grain and escaping through the
foraminous wall of the outer drum.
In a slow rotation of the drum the separate grains or kernels of the mass of grain
will not change their relative position during the greater part of the rotation, but
as the mass of grain introduced is not sufficient to wholly fill the annular space, the
upper surface of the mass of grain will stand at an inclination, as shown at 13,
Fig. 4, and the grains will successively fall and turn over and change their relative
position as they arrive at the highest position in the drum, so that in the continuous
1otation of the drum the grain will be intermittingly agitated, the agitation going
on continuously at certain positions in the mass of grain and the different parts of
the mass coming successively to such position once during each rotation of the
drum.
To carry out the process the grain is introduced into the annular space in the
drum and a shower of water from the pipe 12 is allowed to fall on the drum, which
passes through the perforations and percolates the mass of grain. This shower of
water is supplied at a temperature of from 50 to 60 degrees F. for a period of two
or three days, causing the grain to absorb sufficient moisture to produce germination.
In order that the grain may be evenly and uniformly saturated it may be submitted
to a slight intermittent agitation. This stage of the process corresponds to that
now known as steeping, and when completed the grain should be allowed to drain
and stand, or couch as it is called in ordinary processes, in a quiescent state, to
develop spontaneous heat and prepare itselt for the subsequent germination. This
couching or quiescent state should continue from half a day to a day and a half,
that is, to the time when the temperature of the grain has been raised to the
temperature selected for the next stage by a natural heating process.
The next step is that of germination, or sprouting, and consists in subjecting the
mass of grain to an atmosphere moistened to practically saturation and at a
temperature of about 62 degrees F., the limits as to temperature which are
allowable being from 55 to 70 degrees.
During the passage of this moist atmosphere through the grain it is intermittingly
agitated at intervals of from twenty to forty minutes, preferably about once in
thirty minutes, which may be done by rotating the drum at the proper speed, say
from one and a half to three turns an hour. This operation of intermittingly
agitating the grain and passing the current of saturated air through it is continued
from three to five days, or until the acrospire and rootlets have attained their
proper growth. It is then necessary to stop the sprouting or germination, which
result is accomplished as follows, this step being that of withering or shriveling
above described.
To effect this withering the supply of saturated air is discontinued and a current
of non-saturated air is caused to pass through the mass of grain for from three to
six hours, the temperature of said atmosphere being preferably raised slightly
above that used in germination.

page_text: Subsequent to the germinating stage the rate of intermittent agitation should be
increased to periods of from five to fifteen minutes, preferably to about ten minute
periods, which may be done by increasing the speed of rotation of the drum to
from four to twelve turns an hour.
In the withering stage the rootlets become shriveled and the grain loses its
vitality, and at this step in the process, or before the moisture is wholly expelled,
the grain should be whitened by introducing a suitable bleaching agent, such for
example as sulphurous acid gas or chlorine, into the current of air passing through
the same.
These gases also exercise a beneficial antiseptic effect in that they destroy any
mold spores or other harmful germs which may have been present in the malt or
apparatus.
The quantity of bleaching gas used should be limited to that sufficient to produce
a desired whitening and antiseptic effect; an excess is known to be deleterious to
the finished malt.
Two or three pounds of sulphur and a few ounces of salt burned in the current
of air passing through the apparatus would be sufficient for 250 bushels of ordinary
barley.
The final stage is the drying, and to accomplish this a current of dry hot air is
passed through the grain and to secure the best results its temperature and dryness
should be gradually raised from the temperature and humidity at which the
withering process took place, to a practically dry air preferably from 180 to
220 degrees F. This process commonly requires from twenty to thirty hours and the
rate of intermittent agitation must be greater than in the germinating stage. Unless
the grain is agitated more rapidly in the stage of drying than in that of germina-
tion it will be imperfectly dried owing to its subjection alternately to the drying effect
of the hot air when near the distributing passages and the moistening influence of sub-
sequent contact with wet grains. By a more rapid agitation the drying of the mass
is carried through evenly, all grains practically being subjected to like conditions.
The increase in speed may be made at the beginning of the withering process, or
during withering, or at the beginning of the drying process. This completes the
entire process, the grain having been converted into dry finished malt in one
apparatus without removal.
Having thus described how by proper manipulation of atmospheric and
mechanical agencies in a receptacle adapted thereto, grain may undergo the
several stages of conversion above described, without the ordinary transference
from place to place, I wish to state that my invention is not confined to the
carrying out of the complete process. Certain combinations of the stages of this
process are valuable in conjunction with portions of the old processes. For
instance, if desired, the grain may be steeped previous to its introduction into the
druin. In such case it can be placed in a steep-tub and subjected to that stage as
commonly practiced in the present method of malting, and it can then be intro-
duced into the drum and undergo the other stages in the process in accordance
with the description already given. It may be subjected to the stage of couching
also in the steep-tub, or on a floor, before it is introduced into the drum, these two
stages of the process being manipulated in this manner in existing methods of
malting. Having passed these two stages the grain can he introduced into the
drum and undergo the essential features in the herein described process.
While I have shown and described the process as practiced in a receptacle which
agitates its contents by 10lation at different speeds, and having means for producing
said speeds and for supplying the required variable atmospheric conditions, the
same process may be carried out, although not so effectually, in apparatus of other
kinds, as for example, a stationary receptacle in the form of a vat, the same having
a perforated bottom, such as shown in Figs. 5 & 6. The grain being placed in this
stationary vat 1, is subjected to the various atmospheric conditions previously
described, the air passing through one of the pipes 5, 6, 7, as may be required, to
the open space, and through the perforated bottom of the vat 14, and the variable

page_text: intermittent agitation performed by means of a travelling agitator composed of a
series of screws 15, which travel back and forth through the mass of grain, each
screw lifting the grain from the bottom of the vat and conveying it to the top,
causing an entire change or overturning of the grain.
I am aware that apparatus has been used in the process of malting comprising
a rotating drum for the grain and means to introduce air and moisture thereto,
also stationary receptacles with perforated bottoms provided with agitators, by
which the sprouting of the grain has been accomplished successfully, and it
has also been suggested that the malt may be subsequently dried by passing
blasts of hot dry air through the grain while in said receptacles. but said
apparatus has not been provided with the necessary air ducts by which in the
same machine the intervening step of withering the grain by non-saturated air
may be accomplished, and whereby the grain may be bleached by a proper agent,
and whereby a gradual increase in temperature and dryness of the atmosphere may
be obtained, and no mechanical means have been provided whereby the variable
intermittent agitation may be had at proper times, consequently the grain has not
been properly cured and made marketable as to color and general appearance, and
the processes referred to have been failures, and so far as I am aware the essential
steps for a continuous process have not been discovered nor suggested prior to my
invention thereof.
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 :
I. That improvement in the art of malting which consists of withering the
previously steeped, couched and germinated grain by passing a current of non-
saturated air through it and whitening the same by passing a current of air mixed
with a limited amount of bleaching agent through it in the same apparatus,
substantially as set forth and described.
II. That improvement in the art of malting which consists of whitening the
previously steeped, couched and germinated grain by passing a current of air mixed
with a limited amount of bleaching agent through the same, and curing the grain
by passing a dry hot air through it under increasing dryness and temperature to
practically dry air preferably at a temperature of 180 to 220 degrees F. in the
same apparatus, substantially as set forth and described.
III. That improvement in the art of malting which consists of withering the
previously steeped, couched and germinated grain by passing a current of non-
saturated air through it, whitening the same by passing a current of air mixed with
a limited amount of bleaching agent through it, and curing the grain by passing a
dry hot air through the same under increasing dryness and temperature to
practically dry air preferably at a temperature of 180 to 220 degrees F. producing
thereby a withering, bleaching and curing of the grain in a single apparatus,
substantially as set forth and described.
IV. That improvement in the art of malting which consists, in the stage of
germination, of subjecting the previously steeped and couched grain while inter-
mittingly agitating the same, to the influence of air saturated with moisture at a
temperature of from 55 to 70 degrees F., withering the grain by passing a current
of non-saturated air through it, and whitening the same by passing a current of air
mixed with a limited amount of bleaching agent through it, producing thereby a
continuous germination, withering and whitening of the grain by variable conditions
in a single apparatus, substantially as set forth and described.
V. That improvement in the art of malting which consists, in the stage of
germination, of subjecting the previously steeped and couched grain while inter-
mittingly agitating the same, to the influence of air saturated with moisture at a
temperature of from 55 to 70 degrees F., withering the grain by passing a current
of non saturated air through it, and curing the same by passing a dry hot air
through it while under increased intermittent agitation, producing thereby a

page_text: continuous germination, withering and curing of the grain by variable conditions in
a single apparatus, substantially as set forth and described.
VI. That improvement in the art of malting which consists, in the stage of
germination, of subjecting the previously steeped and couched grain while inter-
mittingly agitating the same, to the influence of air saturated with moisture at a
temperature of from 55 to 70 degrees F., withering the grain by passing a current
of non-saturated air through it, and curing the grain by passing a dry hot air
through it under increasing temperature and dryness from and above the temperature
and humidity used in withering to a practically dry air preferably at a temperature
of from 180 to 220 degrees F. and under increased intermittent agitation, producing
thereby a continuous germination, withering and curing of the grain by variable
conditions in a single apparatus, substantially as set forth and described.
VII. That improvement in the art of malting which consists, in the stage of
germination, of subjecting the previously steeped and couched grain while inter-
mittingly agitating the same, to the influence of air saturated with moisture at a
temperature of from 55 to 70 degrees F., withering the grain by passing a current of
non-saturated air through it, whitening the same by passing a current of air mixed
with a limited amount of bleaching agent through it, and curing the grain by passing
dry hot air through it while under increased intermittent agitation, producing
thereby continuous germination, withering, whitening and curing of the grain by
variable conditions in a single apparatus, substantially as set forth and described.
VIII. That improvement in the art of malting which consists, in the stage of
germination, of subjecting the previously steeped and couched grain while inter-
mittingly agitating the same, to the influence of air saturated with moisture at a
temperature of from 55 to 70 degrees F., withering the grain by passing a current
of non-saturated air through it, whitening the same by passing a current of air
mixed with a limited amount of bleaching agent through it, and curing the grain by
passing a dry hot air through it under increasing temperature and dryness from and
above the temperature and humidity used in withering to a practically dry air
preferably at a temperature of from 180 to 220 degrees F., producing thereby a
continuous germination, withering, bleaching and curing of the grain by variable
conditions in a single apparatus, substantially as set forth and described.
IX. That improvement in the art of malting which consists, in the stage of germi-
nation, of subjecting the previously steeped and couched grain while intermittingly
agitating the same, to the influence of air saturated with moisture at a temperature
of from 55 to 70 degrees F., withering the grain by passing a current of non-
saturated air through it, whitening the same by passing a current of air mixed with
a limited amount of bleaching agent through it, and curing the grain by passing a
dry hot air through it under increasing temperature and dryness from and above
the temperature and humidity used in withering to a practically dry air preferably
at a temperature of from 180 to 220 degrees F. while under increased intermittent
agitation, producing thereby a continuous germination, withering, whitening and
curing of the grain by variable conditions in a single apparatus, substantially as set
forth and described.
X. That improvement in the art of malting which consists of couching the
previously steeped grain by holding it in bulk in a quiescent state to develop
spontaneous heat, germinating the same by intermittingly agitating the grain while
subjecting it to the influence of air saturated with moisture at a temperature of
from 55 to 70 degrees F., withering the same by passing a current of non-saturated
air through it, and whitening the grain by passing a current of air mixed with a
limited amount of bleaching agent through it, producing thereby a continuous
couching, germinating, withering and whitening of the grain by variable conditions
in a single apparatus, substantially as set forth and described.
XI. That improvement in the art of malting which consists in couching the
previously steeped grain by holding it in bulk in a quiescent state to develop
spontaneous heat, germinating the same by intermittingly agitating the grain while
subjecting it to the influence of air saturated with moisture at a temperature of

page_text: from 55 to 70 degrees F., withering the same by passing a current of non-saturated
air through it, and curing the grain by passing a dry hot air through it while under
intermittent agitation, producing thereby a continuous couching, germinating,
withering and curing of the grain by variable atmospheric conditions in a single
apparatus, substantially as set forth and described.
XII. That improvement in the art of malting which consists in couching the
previously steeped grain by holding it in bulk in a quiescent state to develop
spontaneous heat, germinating the same by intermittingly agitating the grain while
subjecting it to the influence of air saturated with moisture at a temperature of
from 55 to 70 degrees F., withering the same by passing a current of non-saturated
air through it, and curing the same by passing a dry hot air through the grain
under increasing temperature and dryness of air from and above the temperature
and humidity used in withering to a practically dry air preferably at a temperature
of from 180 to 220 degrees F. while under increased intermittent agitation,
producing thereby a continuous couching, germinating, withering and curing of the
grain by variable atmospheric and agitating conditions in a single apparatus,
substantially as set forth and described.
XIII. That improvement in the art of malting which consists in couching the
previously steeped grain by holding it in bulk in a quiescent state to develop
spontaneous heat, germinating the same by intermittingly agitating the grain while
subjecting it to the influence of air saturated with moisture at a temperature of
from 55 to 70 degrees F., withering the same by passing a current of non-saturated
air through it, whitening the grain by passing a current of air mixed with a limited
amount of bleaching agent through it, and curing the same by passing a dry hot air
through it while under increased intermittent agitation, producing thereby a
continuous couching, withering, whitening and curing of the grain by variable
atmospheric and agitating conditions in a single apparatus, substantially as set
forth and described.
XIV. That improvement in the art of malting which consists in couching the
previously steeped grain by holding it in bulk in a quiescent state to develop
spontaneous heat, germinating the same by intermittingly agitating the grain while
subjecting it to the influence of air saturated with moisture at a temperature of
from 55 to 70 degrees F., withering the same by passing a current of non-saturated
air through it, whitening the grain by passing a current of air mixed with a limited
amount of bleaching agent through it, and curing the grain by passing dry hot air
through it under increasing temperature and dryness from and above the tempera-
ture and humidity used in withering to a practically dry air preferably at a
temperature of from 180 to 220 degrees F., producing thereby a continuous
couching, germinating, withering, whitening and curing of the grain by variable
conditions in a single apparatus, substantially as set forth and described.
XV. That improvement in the art of malting which consists in couching the
previously steeped grain by holding it in bulk in a quiescent state to develop
spontaneous heat, germinating the same by intermittingly agitating the grain while
subjecting it to the influence of air saturated with moisture at a temperature of
from 55 to 70 degrees F., withering the same by passing a current of non-saturated
air through it, whitening the grain by passing a current of air mixed with a limited
amount of bleaching agent through it, and curing the same by passing a dry hot air
through it under increasing temperature and dryness fiom and above the tempera-
ture and humidity used in withering to a practically dry air preferably at a
temperature of from 180 to 220 degrees F. while under increased intermittent
agitation, producing thereby a continuous couching, germinating, withering,
whitening and curing of the grain by variable atmospheric and agitating conditions
in a single apparatus, substantially as set forth and described.
XVI. That improvement in the art of malting which consists in steeping the
grain by subjecting it to saturation with water at a temperature of from 50 to
60 degrees F. to cause the grain to absorb moisture, draining the same, and then
couching it by holding it in bulk in a quiescent state to develop spontaneous heat,

page_text: germinating the same by intermittingly agitating the grain while subjecting it to
the influence of air saturated with moisture at a temperature of from 55 to
70 degrees F., withering the same by passing a current of non-saturated air through
it, and whitening the grain by passing a current of air mixed with a limited amount
of bleaching agent through it, producing thereby a continuous steeping, couching,
germinating, withering and whitening of the grain by variable atmospheric and
agitating conditions in a single apparatus, substantially as set forth and described.
XVII. That improvement in the art of malting which consists in steeping the
grain by subjecting it to saturation with water at a temperature of from 50 to
60 degrees F. to cause the grain to absorb moisture, draining the same, and then
couching it by holding it in bulk in a quiescent state to develop spontaneous heat,
germinating the same by intermittingly agitating the grain while subjecting it to
the influence of air saturated with moisture at a temperature of from 55 to
70 degrees F., withering the same by passing a current of non-saturated air
through it, aud curing the grain by passing dry hot air through it while under
increased intermittent agitation, producing thereby a continuous steeping, couching,
germinating, withering and curing of the grain under variable and atmospheric
conditions in a single apparatus, substantially as set forth and described.
XVIII. That improvement in the art of malting which consists in steeping the
grain by subjecting it to saturation with water at a temperature of from 50 to
60 degrees F. to cause the grain to absorb moisture, draining the same, and then
couching it by holding it in bulk in a quiescent state to develop spontaneous heat,
then germinating the same by intermittingly agitating the grain while subjecting it
to the influence of air saturated with moisture at a temperature of from 50 to
70 degrees F., withering the same by passing a current of non-saturated air
through it, and curing the grain by passing dry hot air through it under increasing
temperature and dryness from and above the temperature and humidity used in
withering up to a practically dry air preferably at a temperature of from 180 to
220 degrees F. while under increased intermittent agitation, producing thereby a
continuous steeping, couching, withering and curing of the grain by variable
atmospheric conditions in a single apparatus, substantially as set forth and
described.
XIX. That improvement in the art of malting which consists in steeping the
grain by subjecting it to saturation with water at a temperature of from 50 to
60 degrees F. to cause the grain to absorb moisture, draining the same, and then
couching it by holding it in bulk in a quiescent state to develop spontaneous heat,
then germinating the same by intermittingly agitating the grain while subjecting it
to the influence of air saturated with moisture at a temperature of from 55 to
70 degrees F., withering the same by passing a current of non-saturated air
through it, whitening the grain by passing a current of air mixed with a limited
amount of bleaching agent through it, and curing the same by passing dry hot air
through it while under increased intermittent agitation, producing thereby a con-
tinuous steeping, couching, withering, whitening and drying of the grain by variable
humid atmospheric conditions in a single apparatus, substantially as set forth and
described.
XX. That improvement in the art of malting which consists in steeping the
grain by subjecting it to saturation with water at a temperature of from 50 to
60 degrees F. to cause the grain to absorb moisture, couching it by holding it in
bulk in a quiescent state to develop spontaneous heat, germinating the same by
intermittingly agitating the grain while subjecting it to the influence of air
saturated with moisture at a temperature of from 55 to 70 degrees F., withering
the same by passing a current of non-saturated air through it, whitening the grain
by passing a current of air mixed with a limited amount of bleaching agent
through it, and curing the same by passing dry hot air through it under increasing
temperature and dryness from and above the temperature and humidity used in
withering to a practically dry air preferably at a temperature of from 180 to
220 degrees F., producing thereby a continuous steeping, couching, germinating,

page_text: withering, bleaching and curing of the grain under variable humid and atmospheric
conditions in a single apparatus, substantially as set forth and described.
XXI. That improvement in the art of malting which consists in steeping the
grain by subjecting it to saturation with water at a temperature of from 50 to
60 degrees F. to cause the grain to absorb moisture, couching it by holding it in
bulk in a quiescent state to develop spontaneous heat, germinating the same by
intermittingly agitating the grain while subjecting it to the influence of air
saturated with moisture at a temperature of from 55 to 70 degrees F., withering
the same by passing a current of non-saturated air through it, whitening the
grain by passing a current of air mixed with a limited amount of bleaching agent
through it, and curing the same by passing dry hot air through it under increasing
temperature and dryness from and above the temperature and humidity used in
withering up to a practically dry air preferably at a temperature of from 180 to
220 degrees F. and while under increased intermittent agitation, producing thereby
a continuous steeping, couching, germinating, withering, whitening and curing of
the grain under variable humid atmospheric and agitating conditions in a single
apparatus, substantially as set forth and described.
Dated this 26th day of June 1893
F. BOSSHARDT & Co.,
4, Corporation Street, Manchester, Agents to Applicant.