Improvements in or relating to the Treatment of Yeast.
Year: 1899

page_text: Date of Application, 3rd Mar., 1899
PROVISIONAL SPECIFICATION.
Improvements in or relating to the Treatment of Yeast.
I, RICHARD RÜCKFORTH, Merchant, of Pommerensdorferstrasse, Stettin, in the
Empire of Germany, do hereby declare the nature of this invention to be as
follows:-
As is known it is possible, in accordance with the experiments of Pictet and
Yung to expose yeast to intense cold without injuring its vitality; in fact,
microscopical investigations have disclosed no visible changes.
In my experiments I have found that yeast in a frozen state, when suddenly
or rapidly heated, looses its vitality; the cells bursting at temperatures which are
below that at which the protein substances contained therein coagulate. There is,
therefore, here a simple means of securing the cell contents specially rich in
protein substances in far greater quantities than can be obtained by means of other
methods, for in the latter the temperatures required are so high that the total,
or partial coagulation of the protein matter cannot be avoided."
This, process, therefore, consisting in first congealing the yeast then destroying
its vitality by a sudden raising of temperature in order to obtain the contents
of the cells, forms the principal object of my invention. The process itself is
very simple. After having washed and cleansed the yeast, it is exposed in suit-
able vessels, for such a length of time to a temperature below 0° C. (32 F.) as to
congeal it. Refrigerating machines may be advantageously used for this purpose.
It is advisable to subject the yeast to a freezing temperature of say 12° to 15° C.
for a time, so that the yeast will congeal into a hard mass, which can afterwards be
crushed.
The
The yeast having arrived at the latter state, the required amount of heat must
be rapidly supplied. This can be done in the following manner. The yeast, after
having been crushed is heated to the required temperature, (which may vary.
according to ulterior purposes) by water of the desired temperature.
yeast cells, are thereby, destroyed or broken. The same effect is likewise secured by
first crushing the frozen mass between ordinary crushing-rollers and afterwards
passing it over or between heated cylinders, such as are employed in cardboard or
glazing machines. The cylinders may be substituted by heated plates, or any
other device serving the purpose. To obtain the protein of the mass, after it-has
thus been heated, it is pressed, or the protein is lixiviated by water at a tempera-
ture at which the protein contained in the yeast does not coagulate, the admixture
of a small quantity of some acid being of great advantage, inasmuch
as it prevents decomposition of the protein. It is also possible, at this
phase of the process, to treat the mass with proteolytic ferments which will, the
yeast cells being destroyed or burst, digest the albumen more energetically than
when the ferments, as Goodfellowes proposes are added to untreated yeast,
treating the yeast directly, at a temperature of say 38° C. with pepsine and hydro-
chloric acid.
DL11:
1
10
1 1000
BOULT & WADE,
Agents for the Applicant.

page_text: Improvements in or relating to the Treatment of Yeast.
I, RICHARD RÜCKFORTH, Merchant, of Pommerensdorferstrasse, Stettin, in the
Empire, of Germany, 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:-
As is known it is possible, in' accordance with the experiments of Pictet and
Yung to expose yeast to intense cold without injuring its vitality; in fact,
microscopical investigations have disclosed no visible changes.
In my experiments I have found that yeast, in a frozen state, when suddenly
or rapidly heated, looses its vitality: the cells bursting at temperatures which are
below that at which the protein substances contained therein coagulate. There is,
therefore, here a simple means of securing the cell contents specially rich in
protein substances in far greater quantities than can be obtained by means of other
methods, for in the latter the temperatures required are so high that the total
or partial coagulation of the protein matter cannot be avoided.
This, process, therefore, consisting in first congealing the yeast, then destroying
its vitality by a sudden raising of temperature in order to obtain the contents
of the cells, forms the principal object of my invention. The process itself is
very simple. After having washed and cleansed the yeast, it is exposed in suit-
able vessels, for such a length of time to a temperature below 0° C. (32 F.) as to
congeal it. Refrigerating machines may be advantageously used for this purpose.
It is advisable to subject the yeast to a freezing temperature of say-12° to -15° C.
for a time, so that the yeast will congeal into a hard mass, which can afterwards be
crushed.
The yeast having arrived at the latter state, the required amount of heat must
be rapidly supplied. This can be done in the following manner. The yeast after
having been crushed is heated to the required temperature say + 15 C. (which
may vary according to ulterior purposes) by water of the desired temperature. The
yeast cells are thereby, destroyed or broken. The same effect is likewise secured by
first crushing the frozen mass between ordinary crushing rollers and afterwards
passing it over, or between heated cylinders, such as are employed in cardboard or
glazing machines. The cylinders may be substituted by heated plates, or any
other device serving the purpose. To obtain the protein of the mass, after it has
thus been heated, it is pressed, or the protein is lixiviated by water at a tempera-
ture at which the protein contained in the yeast does not coagulate, the admixture
of a small quantity of some acid being of great advantage. inasmuch
as it prevents decomposition of the protein. It is also possible, at this
phase of the process, to treat the mass with proteolytic ferments which will, the
yeast cells having been destroyed or burst, digest the albumen quicker and more
energetically, than when the ferments, act directly upon untreated yeast, as
Goodfellowes proposes to treat the yeast directly, at a temperature of say 38° C.
with pepsin and hydrochloric acid.
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. A process for the treatment of yeast consisting in congealing the yeast,
destroying the cells by subsequent heating and obtaining the contents of the burst
cells, substantially as described.
2. A process for the treatment of yeast consisting in congealing the yeast,
breaking up the mass so formed, and rapidly heating to a temperature of about

page_text: +15° C., and finally extracting the protein by pressure or lixiviation, sub-
stantially as described.
3. A process for the treatment of yeast consisting in congealing the yeast, break-
ing up the mass so formed and rapidly heating to a temperature of about + 15° C.
adding proteolytic ferments, and finally extracting the protein, substantially as
lescribed.
1
..
BOULT, WADE & KILBURN,
Agents for the Applicant.