IMPROVEMENTS IN THE MANUFACTURE OF GERMAN YEAST
Year: 1881

page_text: LETTERS PATENT to Gerard Wenzeslaus von Nawrocki, Proprietor of the Firm
of J. Brandt and G. W. v. Nawrocki, Patent Solicitor and Civil Engineer, of
124, Leipzigerstrasse, Berlin, Germany, for an Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF GERMAN YEAST." A communication from Carl
Paulmann, of Hanover, in the German Empire.
PROVISIONAL SPECIFICATION left by the said Gerard Wenzeslaus von
Nawrocki at the Office of the Commissioners of Patents on the 28th
September 1881.
GERARD WENZESLAUS VON NAWROCKI, Proprietor of the Firm of J. Brandt &
G. W. v. Nawrocki, Patent Solicitor and Civil Engineer, of 12+, Leipzigerstrasse,
Berlin, Germany. 'IMPROVEMENTS IN THE MANUFACTURE OF GERMAN YEAST.”
(A communication from Carl Paulmann, of Hanover, in the German Empire.)
"
I. For washing in the mash tun there is used per 1000 litres (220 gallons)
contents of the tun,-
68 pounds of finely ground well husked malt meal.
235 pounds, not too finely ground, somewhat husked rye meal, 20 pounds husked
buckwheat meal, and about 450-500 litres (100-110 gallons) water.
For preparing the first onset yeast ("Anstellhefe ") there is used pro 1000 litres
(220 gallons) of contents of mash tun,-
18, pounds of coarse well husked malt meal.
18, pounds coarse middling husked rye meal and 37 litres (8 gallons) of water
at 171°F.
The mashing water required in the mash tun is brought to the temperature of
122° F., then the malt is added while stirring, and is left standing 10 to 20 minutes
for dissolving.
Then the rye meal is added while constantly stirring, and at last the buckwheat
meal, with the hot water as required.
The whole mass at the end of this process has a slimy milky appearance, and the
temperature is now raised from 122 to 183° F., and it is left quietly standing for

page_text: half an hour, whereupon it is slowly heated while stirring vigorously until it at
last reaches a temperature at 142 to 143° F. It is then left thus quietly, and
covered up as male mash for two hours to dissolve, that is, form sugar.
The cooling then follows, which should be as slow as possible, and it is hereby to
be observed that the cooling is to be slowest at 84 to 95° F. The cooling has to
be such that after addition of the yet required water a starting temperature of 65°
F. is attained in the fermenting tun, whereby the first onset yeast is added after
1/2 pound of previously well diluted sulphuric acid, pro 220 gallons contents of mash
tun.
The addition of water in the mash tun depends upon how many tuns are to be
mashed at one time in a mash tun, but the yield of yeast and alcohol, as well
as the durability of the yeast, is the less by a thinner admixture and strong
stirring.
3 to 4 hours after the addition of the yeast the fermentation begins, thereupon
the formation of foam; the foam will rise 12-13 inches. If this part of the process
began, say, at noon, then the yeast formation should begin the next morning at
3 or 4, that is, large turbid bubbles free from bran should form. At 5 o'clock the
tun should be at maturity, that is, the bubbles should have a milky turbid look,
and the foam gone down 1 to 1'/, inches.
At this stage, during which the mash in the tun has risen 9° F., the clearing off
of the yeast foam begins, whereby it is to be observed that to make the yeast
keep it is of importance not to clear the foam off before the lapse of 16 hours from
starting with the "first_onset," and this is_regulated_by_suitably_earlier_or_later._.
yeast addition, and by the onset temperature.
The bubbles are cleared off into a conveniently placed receiver down to the level
of the mash; this is only then repeated when large turbid bubbles are formed on the
surface again, which at first takes place every five minutes, but later on every ten
to fifteen minutes.
The yeast foam which has been ladled off sets into a thick milky consistency,
and must be carefully filtered through two hair sieves with different size meshes:
by means of a wooden dolly. The so cleansed yeast is then put into a tub covered
with water for settling and partial removal of the acid, the water being put in first
and then the thin fluid yeast. After some 10-12 hours the yeast has set well.
The water is then run off and distilled off, as it contains 12 to 15 per cent.
alcohol.
The yeast is mixed with the required addition of potato starch, according to the
quality desired, and then passed through a finely perforated strong brass sieve;
then pressed, if possible, in a filter press, and lastly formed into pound parcels by a
machine for dividing into pounds and parts of same, and packed into paper or linen
bags.
Instead of using the whole quantity of rye, up to half that weight of maize, groats
may be added.
The maize is for that purpose boiled at a temperature of 190 to 212° F. in water
in the mash tun, or in a special vessel, and then added to the rye groats. In order
that the maize should not become lumpy the stirring apparatus must be put to
work in the vessel in question.
The maize may also in the form of whole grains be cooked by steam in cylindrical
vessels, and reduced in a suitable mill; the later treatment with the rye and malt
is then the same as above described.
The object of adding the maize is to reduce the costs, as it is considerably cheaper
in price than rye.
Instead of the kiln malt groats a suitable quantity of green malt may be applied,
which before the mashing is reduced by a malt grinder; further, instead of the
addition of sulphuric acid, a suitable quantity of muriatic acid may be used, or
clarified waste water from the still.
The residue coming from the distilling apparatus is for this purpose conveyed to
a cooling and clarifying vat, and settles there, and the clarified water is put into

page_text: the mash tun instead of the sulphuric acid or muriatic acid, and in a quantity of
30 to 40 per cent. of the contents of the mash; this clarified water must first be
cooled down to 60° F.
11. The preparation of the first onset yeast is as follows:-For every 220 gallons
of mash tun contents there is used for mashing every 36 hours before the mashing
in the fermenting tun 18 pounds coarse well husked malt groat; 181, pounds.
coarse husked rye groats, and 8 gallons of boiled water of 156° F.
These are put in the yeast vessel in question; this mash must be vigorously
worked, so that it, although little water and much gronts are used, may become
slimy, and have a final temperature of 142 to 144° F. The mass remains covered
2 hours, is then again worked vigorously and continuously, so that there are no
lumps in the mash, and so that it is sticky and juicy. The whole mash is then left
untouched for about 27 hours, is thereupon stirred, and its temperature tested;
if it is above 77° F. it is cooled by means of a cooler; if it is below 77° F. it is
raised to that temperature by the passage of warm water, and on the first day there
is added, per 220 gallons of contents of tun, 2 pounds of pure, sound, mature, and
quite starch free German yeast 9 to 10 hours before the application at a tempera-
ture of 77° F.
The German yeast to be applied requires for dissolving only very little water,
and at most 2 gallons of water per pound; it should therefore be dissolved
several hours previously by simply breaking up the yeast, pouring the water over
it, and before use press it out through a gauze bag in some gallons of onset inass.
The yeast which has been set on in hot weather (72-74° F.) at a temperature of
77° F. is covered over, and must before uso be heated up to at least 95° F.
While heating from 77 to 88° F., only 1 gallons of mother yeast (mutter hefe)
per 220 gallons contents of mashed tun are abstracted and placed in a cool place in
order to prevent further heating. A cooling down to 61° F. is most advisable, and it
must be observed that the mother yeast should never be cooler that 54° F., also that
it should not keep at 66° F. for more than four hours, but should be kept at 59
to 61° F.
The further onsets take place every day exactly at the same time and by the
same temperature, but besides the 1/4 gallons of mother yeast per 220 gallons of
mash space previously taken off in the morning there may each time be one pound
of pure unadulterated German yeast dissolved in water per 220 gallons of mash
space for the onset. Mother yeast in like quantity is then taken off at the sume
heat, and equally treated and maintained as described.
The onset yeast is only then mature and really useful for attaining the highest
and best yield when its temperature has risen from 77° F. to at least 93 to 95° F.
In the fermenting tun the saccharometer, according to "Balling," should not show
more than 12%, but should after the fermentation is finished and before the
distillation have gone down to 1%.
In order to cheapen the pure yeast, and partly also to make it keep better, a
quantity of potato starch Hour may be added. The same is in a wet state mixed
intimately with the damp yeast, Inter on freed from water by means of a filter
press or other suitable contrivance, then cut into square pieces on the yeast forming
and dividing machine, and packed in paper for transmission. In order to prevent
the damp from exuding the paper should first be steeped in salt water.
Instead of the potato starch flour dry beer yeast may be added; this only serves
to make the German yeast cheaper. After the lapse of at lest 12 or 16 hours after
the yeast foam has been removed from the fermenting tuns the mash remaining in
the latter is removed to a distilling, apparatus, and the alcohol parts removed by
distilling, aud reudered liquid. Thus a second product, namely, spirits, is
obtained.

page_text: -37-litres-(8-gniions)-or-water at 171 ranrenne
The mashing water required in the_mash_tun_is_brought-to-the-temperature-of-
122° Fahrenheit, then the malt is added while stirring, and is left standing 10 to
20 minutes for dissolving.
Then the rye meal is added while constantly stirring, and at last the buck wheat
meal with the hot water, as required.
2
The whole mass at the end of this process has a slimy milky appearance, and
the temperature is now raised from 122 to 133° Fahrenheit, and it is left quietly
standing for half an hour, whereupon it is slowly heated while stirring vigorously 2
until it at last reaches a temperature of 142 to 143° Fahrenheit; it is then left
thus quietly, and covered up as made mash for 2 hours to dissolve, that is,
saccharification.
The cooling then follows, which should be as slow as possible, and it is hereby
The 3
to be observed that the cooling is to be slowest at 84 to 95° Fahrenheit.
cooling has to be such that after addition of the yet required water a starting
temperature of 65° Fahrenheit is attained in the fermenting tun, whereby the first
onset yeast is added after '/, pound of previously well diluted sulphuric acid pro
220 gallons contents of mash tun has been put into the mash tun also.
The addition of water in the mash tun depends upon how many tuns are to be 3
mashed at one time in a mash tun; but the yield of yeast and alcohol, as well as
the durability of the yeast, is the most favourable the thinner the mixture and the
stronger the stirring.
3 to 4 hours after the addition of the onset yeast the fermentation begins,
thereupon the formation of fuam; the foam will rise 12-13 inches. If this part of
the process begun, say, at noon, then the yeast formation should begin the next
morning at 3 or 4, that is, large turbid bubbles free from bran should form. At
5 o'clock the tun should be at maturity, that is, the bubbles should have a milky
turbid look, and the foam gone down to 1 to 1, inches.
At this stage, during which the mash in the tun has risen 9° Fahrenheit, the 4
clearing off of the yeast foam begins, whereby it is to be observed that to make
the yeast keep it is of importance not to clear the foam off before the lapse of 16
hours from starting with the "first onset," and this is regulated by suitably earlier
or later yeast addition, and by the onset temperature.
The bubbles are cleared off into a conveniently placed receiver down to the
level of the mash. This is only then repeated when large turbid bubbles are formed

page_text: on the surface again, which at first takes place every five minutes, but later on
every ten to fifteen minutes.
The yeast foain which has been ladled off sets into a thick milky consistency,
and must be carefully filtered through two hair sieves with different size meshes,
by means of a wooden dolly. The so cleansed yeast is then put into a tub coveredl
with water for settling and partial removal of the acid, the water being put in
first, and then the thin fluid yeast. After some 10-12 hours the yeast has set
well.
The water is then run off and distilled off as it contains 12 to 15 per cent.
alcohol.
The yeast is passed through a finely perforated strong brass sieve, then pressed,
if possible, in a filter press, and lastly formed into pound parcels by a machine
for dividing into pounds and parts of same, and packed into paper or linen bags.
Instead of using the whole quantity of rye, up to half that weight of maize,
groats may be added.
The maize is for that purpose boiled, at a temperature of 190 to 212° Fahrenheit,
in water in the mash tun, or in a special vessel, and then added to the rye groats.
In order that the maize should not become lumpy the stirring apparatus must be
put to work in the vessel in question.
The maize may also, in the form of whole grains, bo cooked by steam in
cylindrical vessels, and reduced in a suitable mill; the later treatment, with the
rye and malt, is then the same as above described.
The object of adding the maize is to reduce the costs, as it is considerably cheaper
in price than rye.
Instead of the kiln malt groats a suitable quantity of green malt may be applied,
which before the mashing is reduced by a small grinder; further, instead of the
addition of sulphuric acid a suitable quantity of muriatic acid may be used, or
clarified wash residue from the still.
The wash or wort residue coming from the distilling apparatus is for this
purpose conveyed to a cooling and clarifying vat and settles there, and the clarified
water is put into the fermenting back instead of the sulphuric acid or muriatic
acid, and in a quantity of 30 to 40 per cent. of the contents of the mash; this
clarified water must first be cooled down to 60° Fahrenheit.
The preparation of the first onset yeast, or so called "artificial yeast," is as
follows For every 220 gallons of mash tun contents there is used for mashing
every 36 hours, before the mashing in the fermenting tun, 18 pounds coarse
well husked malt groats; 18, pounds coarse husked rye groats, and 8 gallons of
boiled water of 150° Fahrenlicit.
These are put in the yeast vessel in question. This mash must be vigorously
worked, so that it, although little water and much groats are used, may become
slimy and have a final temperature of 142 to 144° Fahrenheit. The mass remains
covered 2 hours, is then again worked vigorously and continuously, so that thero
are no lumps in the mash, and so that it is sticky and juicy.
The whole mash is then left untouched for about 27 hours; is thereupon stirred
and its temperature tested; if it is above 77° Fahrenheit it is cooled by means of
a cooler; if it is below 77° Fahrenheit it is raised to that temperature by the
passage of warm water, and on the first day there is added, per 220 gallons of
contents of tun, 2 pounds of pure, sound, mature, and quite starch free Gerinan
yeast 9 to 10 hours before the application at a temperature of 77° Fahrenheit.
The German yeast to be applied requires for dissolving only very little water,
and at most 2 gallons of water per pound; it should therefore be dissolved several
hours previously by simply breaking up the yeast, pouring the water over it, and
before use press it out through a gauze bag in some gallons of onset mass. The
yeast which has been set on in hot weather (72-74° Fahrenheit) at a temperature
of 77° Fahrenheit is covered over, and must before use be heated up to at least
95° Fahrenheit.
While heating from 77 to 88° Fahrenheit only 13%, gallons of mother yeast

page_text: (mutter hefe) per 220 gallons contents of mashed tun are abstracted, and placed in
a cool place in order to prevent further heating. A cooling down to 61° Fahrenheit
is most advisable, and it must be observed that the mother yeast should never be
cooler than 54° Fahrenheit, also that it should not keep at GG° Fahrenheit for more
than 4 hours, but should be kept at 59 to 61° Fahrenheit.
5
The further onsets take place overy day exactly at the same time and by the
same temperature, but besides the 13 gallons of mother yeast per 220 gallons of
mash space previously taken off in the morning, there may each time be one pound
of pure unadulterated German yeast dissolved in water per 220 gallons of mash
pace for the onset. Mother yeast in like quantity is then taken off at the same 1
heat, and equally treated and maintained, as described.
The onset yeast is only then mature, and really useful for attaining the highest
and best yield when its temperaturo has risen from 77° Fahrenheit to at least
93 to 95° Fahrenheit. In the fermenting tun the saccharometer, according
to "Balling," should not show more than twelve per cent., but should after 1
the fermentation is finished and before the distillation have gone down to
1 per cent.
Instead of the so-called "artificial yeast," as described before, pure dry pressed
ready German yeast may be applied as a fermenting medium.
For this purpose there must be taken off the mash in the mash tun a portion of a
5 gallons of sweet saccharified mash at a temperature of 82° Fahrenheit for every
22 gallons of mash in the fermenting back, and put into a separate onset vat.
To these 22 gallons must be added 4 to 6 pounds.of-German-yeast-dissolved-in-
water of the same temperature, and both mixed together.
These-22-gallons-of-mash, together with the 4 pounds of yeast, will commence
fermenting, and rise about 6 inches within half an hour, whereupon the mixture
must be added to the main mash in the fermenting back.
The addition of sulphuric acid or cleared residue-water of mash into the fer-
menting back must take place after or before in the way described already. The
wet yeast must be freed from water as much as possible by means of a filter press
or other suitable contrivance, then cut into square pieces on the yeast forming and
dividing machine, and packed in paper for transmission. In order to prevent the
damp from exuding, the paper should first be steeped in salt water.
After the lapse of at least 12 or 16 hours after the yeast foam has been removed
from the fermenting tuns, the mash remaining in the latter is removed to a distilling
apparatus, and the alcohol parts removed by distilling, and rendered liquid; thus a
second product, namely, spirits, is obtained.
I claim the manufacture of German yeast from grains by the application of
sulphuric acid, or muriatic acid, or sour clarified wash residue, substantially in the
manner herein before described.
In witness whereof, I, the said Gerard Wenzeslaus von Nawrocki, have
hereunto set my hand and seal, this Twentieth day of March, in the
year of our Lord One thousand eight hundred and eighty-two.
GERARD WENZESLAUS VON NAWROCKI
(T.S)