Improvements in the Manufacture of Yeast.
Year: 1893

page_text: Date of Application, 21st Oct., 1893
Complete Specification Left, 20th Aug., 1894-Accepted, 22nd Sept.. 1894
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Yeast.
I WILLIAM STEVENS SQUIRE of Clarendon House St. Johns Wood Park,
London N.W. Chemical Engineer do hereby declare the nature of this invention
to be as follows:-
--
This invention relates to a special treatment of distillers spent wash, and to
modifications of processes described in some of my previous Specifications herein-
after mentioned.
•
I find that, when distillers spent wash is heated under pressure to a temperature
corresponding to about two atmospheres above the atmospheric pressure, it is
rendered less viscid, and more suitable for the manufacture of yeast. The spent
wash is therefore heated in a suitable apparatus to this temperature, and is then
filtered or allowed to subside. The spent wash thus obtained is perfectly clear and
bright, which is not the case with spent wash which has not undergone this
treatment. This I call purified spent wash.
In the ordinary process of brewing in distilleries the maize, dari, rice, and other
refractory grain are treated with water at or about the boiling point. By this
treatment most of the albuminous matters are coagulated, and lost for the yeast
manufacture. In order to avoid this, the maize or other refractory grain (before
it is submitted to the action of very hot water) is treated with water, water
acidulated with mineral acid, spent wash, or preferably spent wash, purified as
above described, at a temperature not exceeding 130° Fahr. for some hours,
preferably with agitation.
The liquor is then run off, and the residual grain is treated with water at or near
the boiling point, and added to the malt and other less refractory grain in the mash
tun, as in the usual way of grain distillery brewing.
The albuminous solution which has been run off, if it has been prepared with
water, is to be used instead of water for mashing malt, rye or other suitable grain
"before the addition of the boiled maize, as described in any Specification No. 5457
of 1886. If, on the other hand, the albuminous solution has been prepared with
acidulated water, spent wash, or preferably purified spent wash, such solution is to
be used instead of spent wash in the operations described in my Specifications
No. 12058 of 1885, No. 12463 of 1885, No. 5457 of 1886, and No. 8082 of 1886.
The above process may be modified, so as to prepare a wort suitable for the
manufacture of yeast when a current of air is blown into it after the addition
of the seed yeast.
In order to accomplish this, the ground maize or other
suitable grain is treated as above mentioned in order to obtain an albuminous
solution and the residual maize is treated at or about the boiling point with water.
While this is going on, ground malt is mashed with ground grain, preferably rye,
with water or with the albuminous solution, if water has been used to extract the
albumen, and the boiled maize is then added in such a way that the resulting
mixture will have a temperature of about 145° Fahr. When the saccharification
is complete, the acidulated water, or the spent wash, or the purified spent wash or
the albuminous solution (if either of these liquids have been used to prepare it) is
added so as to obtain a wort of specific gravity 1.030 or thereabouts. The resulting
wort is then clarified by any known process of filtration, preferably by means of a
filter press, and cooled to about 80° Fahr. Yeast is then added and air blown into
the wort until fermentation is complete. The yeast is then collected, washed and
pressed. The resulting wash may then be distilled to recover the spirit.

page_text: A further improvement, by which a larger quantity of spirit is recovered, consists
in operating as last described, but the solid matter removed from the wort by the
filter press is treated with water under a pressure of three atmospheres or there-
abouts, and the liquid so obtained, separated from the solid matter by any known
process, is to be used instead of water for boiling the maize after the treatment to
remove the albuminous matters.
Instead of adding the purified spent wash, or the ordinary spent wash or the
acidulated water or the albuminous solution prepared with any of these liquids, to
the worts before filtration, the worts may be filtered first, and the albuminous
solution may be added afterwards, if sufficiently clear after separate filtration. This
addition may take place before or after the cooling of the worts or of the spent
wash albuminous solution.
Dated this 21st day of October 1893.
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Yeast.
1, WILLIAM STEVENS SQUIRE, of Clarendon House, St. Johns Wood Park,
London, N.W., Chemical Engineer, 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:—
This invention relates to a special treatment of distillers' spent wash, and to
modifications of processes described in some of my previous Specifications.
I find that, when distillers' spent wash is heated under pressure to a temperature
corresponding to about two atmospheres above the atmospheric pressure, it is
rendered less viscid, and more suitable for the manufacture of yeast. The spent
wash is therefore heated in a suitable apparatus to this temperature, and is then
filtered or allowed to subside. The spent wash thus obtained is perfectly clear
and bright, which is not the case with spent wash which has not undergone this
treatment. This I call purified spent wash.
In the ordinary process of brewing in distilleries, the maize, dari, rice, and other
refractory grain are treated with water at or about the boiling point.
By this
treatment most of the albuminous matters are coagulated, and lost for the yeast
manufacture. In order to avoid this, the maize or other refractory grain (before
it is submitted to the action of very hot water) is treated with water, water
acidulated with mineral acid, spent wash, or preferably spent wash, purified as
above described, at a temperature not exceeding 130° to 140° Fahr. for some
hours preferably with agitation.
The liquor is then run off, and the residual grain is treated with water at or
near the boiling point, and added to the malt and other less refractory grain in the
mash tun, as in the usual way of grain distillery brewing.
The albuminous solution which has been run off, if it has been prepared with
water, is to be used instead of water for mashing malt, rye or other suitable grain
before the addition of the boiled maize, as described in my Specification No. 5457
of 1886. If, on the other hand, the albuminous solution has been prepared with
acidulated water, spent wash, or preferably purified spent wash, such solution is to
be used instead of spent wash in the operations described in my Specifications
No. 12058 of 1885, No. 12463 of 1885, No. 5457 of 1886, and No. 8082 of 1886.
The above process may be modified, so as to prepare a wort suitable for the
manufacture of yeast when a current of air is blown into it after the addition of
the seed yeast. In order to accomplish this, the ground maize or other suitable
grain is treated as above mentioned in order to obtain an albuminous solution and
the residual maize is treated at or about the boiling point with water.
While this

page_text: is going on, ground malt is mashed with ground grain, preferably rye, with water
or with the albuminous solution, if water has been used to extract the albumen, and
the boiled maize is then added in such a way that the resulting mixture will have
a temperature of about 145° Fahr. When the saccharification is complete, the
acidulated water, or the spent wash, or the purified spent wash or the albuminous
solution (if either of these liquids have been used to prepare it) is added so as to
obtain a mixture resulting in a slightly acid wort of specific gravity 1030 or
thereabouts and of such a degree of acidity that 100 thereof will be neutralised
by 4 of normal soda solution. The resulting wort is then clarified by any
known process of filtration, preferably by means of a filter press, and cooled to
about 80° Fahr. Yeast is then added and air blown into the wort until fermentation
is complete. The yeast is then collected, washed and pressed. The resulting wash
may then be distilled to recover the spirit.
A further improvement, by which a larger quantity of spirit is recovered,
consists in operating as last described, but the solid matter removed from the wort
by the filter press is treated with water at a temperature corresponding to a
pressure of three atmospheres or thereabouts and the liquid so obtained, separated
from the solid matter by any known process, is to be used instead of water for
boiling the maize after the treatment to remove the albuminous matters.
Instead of adding the purified spent wash, or the ordinary spent wash or the
acidulated water or the albuminous solution prepared with any of these liquids, to
the worts before filtration, the worts may be filtered first, and the albuminous
solution may be added afterwards, if sufficiently clear or if not sufficiently clear
after separate filtration. This addition may take place before or after the cooling
of the worts or of the spent wash albuminous solution.
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 in respect of the manufacture of yeast is :-
1. The process of first subjecting distillers' spent wash to a preliminary heating
under pressure and then purifying the same by filtration or subsidence, substantially
as described.
2. The use of the purified spent wash referred to in the preceding claim in lieu
of ordinary spent wash in the processes set forth in my previous Patents herein
before referred to.
3. The process of first producing an albuminous solution by treating grain,
before boiling, either with water ordinary or purified spent wash or acidulated
water at a temperature below that at which the albumen coagulates and then
employing such albuminous solution for mashing grain substantially as described.
4. The process of treating the residues from the mashings with hot water under
pressure and employing the separated liquid for boiling the grain after this has
been treated for the removal of the albuminous matters, substantially as and for
the purposes described.
Dated this 17th day of August 1894.
ABEL & IMRAY,
Agents for Applicant.