Improvements in the Method of and in Means and Appliances for Testing Yeast and Barm.
Year: 1894

page_text: Date of Application, 7th Nov., 1894-Accepted, 8th Dec., 1894
COMPLETE SPECIFICATION.
Improvements in the Method of and in Means and Appliances for
Testing Yeast and Barm.
I, ANTONIN ČEČETKA, of Vinohrady, Prague, Bohemia, in the Empire of Austria,
Brewer, do hereby declare the nature of my said invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement:-
The object of my invention is to effect improvements in the method of and in
means and appliances for testing yeast and barm, for industrial purposes. The
fermenting force of yeast and harm is generally determined by the amount of
carbonic acid, which in a given time is produced by a normal quantity of the yeast
or barm, after being mixed with a normal quantity of the substance to be fermented.
A number of methods and forms of apparatus are known for the purpose of
obtaining and measuring this amount of carbonic acid, and many are quite sufficient
for a chemical laboratory. My improvement consists in a new method and
apparatus, with the object of enabling ordinary persons to determine the fermen-
tative force of his yeast or barm, without any chemical or experimental knowledge,
my method requiring only the management of an ordinary good scale.
And in order that my said invention may be particularly described and ascertained,
reference is hereby made to the accompanying drawings, in which similar letters
of reference indicate corresponding parts.
Fig. 1 is a vertical sectional elevation, illustrating one form of apparatus in
accordance with my invention.
Fig. 2 is a horizontal section on the line
Fig. 3 is a vertical sectional elevation of
of Fig. 1.
apparatus for the preparation of the
barm sample for use in combination with that shown in Fig. 1.
Fig. 4 is a top view of Fig. 3.
Fig. 5 is a vertical sectional elevation of a modification of the apparatus.
Fig. 6 is a section on the line xx of Fig. 5.
I fill a vessel A with a mixture of the substance to be fermented and the yeast
or barm to be tested, both in given quantities. The vessel A is then corked and
heated gently, over a lamp B, so as to sustain a temperature suitable for producing
fermentation. For this purpose the whole can be enclosed in a thermostat C. This
may consist of a cone of wood or papier maché, or any other bad conductor of heat.
A thermometer t may be used for indicating the temperature. Apertures a, a, are
made in the thermostat C, the extent of opening being regulated by a movable
ring D, provided with corresponding holes b. If the ring D covers the holes μ
entirely, the heat will be increased, and when the ring D only partly covers the
holes, the heat inside the thermostat will be lessened; and it will reach its minimum,
when the holes b coincide with the holes a.
Other methods of heating may be employed, the above arrangement being merely
given as an example.
In combination with the above described apparatus for producing carbonic acid by
fermentation of the substance in the vessel A, I use two other vessels or bottles
and F, or the like. The vessel E is filled with water or any other liquid neutral to
the carbonic acid, and is then corked. The vessel E is connected with the vessel A
by means of a tube H, and the vessel E is connected with the bottle F by another
tube J, which tubes descend nearly to the bottom of both the bottles E and F,
the latter being open and empty.
+
The fermentation in A produces carbonic acid, which drives a portion of the
water from E into F.
'

page_text: After a given space of time, say an hour for instance, the process will be
completed. The relative increase in the weight of the vessels E and F indicates
the weight of the carbonic acid, which has been produced in .that time by the
fermentation in the vessel A. The weight of the water in the vessel F will indicate
the volume of the produced carbonic acid. The quantity of the carbonic acid,
produced in a given time, being the measure of the fermenting force, it is evident,
that in this simple way the weight of the vessels indicates the quality of the yeast
'or barm.
'
This simple process and apparatus will be found sufficient for some industries,
where the yeast is to be used just as it is produced. In some other industries, for
instance for breweries, distilleries aud the like, the sample of barın is prepared in
the following manner, before being put into the vessel A, together with the
fermenting liquid. I take with a flat knife or the like, part of the barm in question
and fill a measured spoon formed of wood, glass and the like, with it, so that it can
be mixed with water with the aid of the spoon in a small glass G, this glass G being.
provided with an indicator mark q, equal to the exact height of the measure of the
sample, say one cubic centimeter for instance. Over the glass G, I suspend- a
syringe P, upon a frame M N. The cylinder P of the syringe is provided with a
flange S, the position of which is calculated so as to enable the operator to push
the syringe exactly at the level of the mark q, in which position the flange S rests
upon the upper edge of the glass G.
The rod of the piston L is guided at f, the upper part of the rod being screw
threaded and suspended by the flyout m upon the support N.
After a while, when the barm has settled, the cylinder P is pressed down so that
the flange or brackets S rest on the edge of the glass G, and the end of the
cylinder P stands exactly on a level with the quantitative mark 9. By this
movement the greater part of the water and barm standing over 9 is drawn into
the cylinder P. The rest of it is carefully drawn off while holding the bracket S
upon the edge of G, and turning at the same time the nut m, so as to screw the
piston L upwards. All what remains in the glass G under the quantitative mark y
is afterwards brought into the vessel A, where it is mixed with the fermented stuff
as above described.
4
This forms a very simple and expeditious means of measuring and washing the
sample of yeast or barm, but I do not bind myself to the use of the apparatus
shown in Fig. 3, the chief object being to have it measured and washed by any
convenient process.
In the modified arrangement shown in Figs. and 6, E is an inverted vessel,
mounted over or upon a vessel F1. The communicating tubes H, K, and j, are
preferably formed of metal, H and K being coupled together at K. The tube K
reaches nearly to the top of El, which is filled with water or other suitable fluid,
as (for instance) a saturated solution of salt. Cocks K' and j' are fitted as shown.
The vessels E and F may be graduated for showing the cubical contents of the
vessels, and the quantities withdrawu.
The manipulation of this apparatus is very simple. The vessel E' being full:
as soon as the process of fermentation begins, the cocks K' and ' are opened.
The carbonic acid gas which is produced by the fermentation of the sample
in A enters into E¹ and displaces part of the liquid, of a similar volume to
the gas produced, the liquid falling into F¹. At the end of the process the
corks K and are shut, and the quantity of water displaced from E' (or the
carbonic acid gas produced) is indicated upon the graduated scales of the glasses,
or is found by the difference in weight of the respective vessels E' and F¹.
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 and apparatus for the determination of the fermenting
energy of yeast and barm by the quantity of carbonic acid produced by a given

page_text: quantity of yeast or barm in a given quantity of the fermented substance, and
in a given time, by means of vessels A, E and F, the vessel E being filled
with water, (or other liquid neutral to carbonic acid) suitably closed and connected
for receiving the carbonic acid produced by the fermentation, and the vessel F
being empty and open, and receiving the water which the carbonic acid displaces
from E, by means of a tube J reaching nearly to the bottom of both vessels,
the weights of the respective bottles or vessels indicating the weight of the
produced carbonic acid, while the weight of the water driven into indicates
its volume, substantially as herein before described and illustrated by Figs. 1
and 2 of the drawings.
2. The method of and apparatus for measuring and washing the sample of the
barm in a glass, provided with a quantitative mark q and syringe P, L, the
syringe being provided with a flange or brackets S, guide, and screw and
nut m, substantially as and for the purpose herein before described and illustrated
by Fig. 3 of the drawings.
3. The modified form and arrangement of apparatus substantially as and
for the purposes herein before described and illustrated by Figs. 5 and 6 of the
drawings.
4. The improvements in the method of and in means and appliances for testing
yeast and barm, substantially as herein before described and illustrated by the
drawings.
Dated 7th Nahan 100
GEO.
DOWNING,
8, Quality Court, London, W.C., Agent.