Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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FILE, IPti~ THiS ~P~EtE~)
TRANSLATION
21~21-259
The present inventlon relates to a process and a devlce
for produclng leaven, in which the leaven preparation is moved
through a serles of fermenters ln a chain, and into a storage
container, the time of passage through the serles of fermenters
e~ualling the rlpenlng time of tile leaven.
Since ancient tlmes, in order to make the leaven that ls
requlred to bake bread, flour and water and a small quantlty of
prepared leaven are mlxed together to form a leaven preparatlon.
This leaven preparation begins to ferment and after a speclfic
ripening tlme develops into leaven that can be baked. When this
is done, the quality of the l~aven that i5 produced and the yield
o~ this can be controlled by the ripening temperature, the
rlpening tlme, ancl by the tlme at which the leaven preparation ls ;
added. Thus, for example, a long ~ipening tlme results ln a
partlcularly high quallty leaven.
Durlng industrial production of bread that is baked from
leaven~ a long ripenlny time for the leaven can be problematic
because it is only by using a great deal of expensive equipment
that it is possible to enfiure that there is always sufficient
leaven ~or baking available.
A further problem is the fact that leaven that is ready
for use can only be stored for a limite~ time.
There are many possibilities for reducing the ripening
time of the leaven, for lncreasing the yield of leaven, or for
producing a leaven that can be stored for a longer time. Thus,
for example, increasing the temperature of the leaven leads ~o a
reduction of the ripening time. However, at the same time,
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21421-259
lncreaslng the leaven temperature also lncreases the risk that the
volatile acid fraction of the leaven that is produced by the
bacteria increases markedl~l ln proportlon to the base acid of the
leaven. Because of the fact that this volatile acid fraction is
105t during the baking process, the taste of the bread that is
balced from leaven produced ln a short tlme is degraded. Compared
to a bread produced from a leaven that has been left undisturbed
at a constant temperature of 25-35C fo~ a ripenlng elme that has
not been shortened, it has a taste tha~ is less aromatic.
DE 24 23 157 describes a process for produclng leaven,
in which the leaven starter [Sauerteigansat~] is passed along a
number of fermenters that are connec~ed in a chain, wh~n the
passage time through the fermenter chain equals the ripening time
of the leaven. When this is done, ~he leaven is prepared
[angesetzt] throuyh several stages, additional additives belng
incorporated in each stage. GB-A-934255 describes the use of a
fermentation starter in a number of tanks that equals the
fermentation time plus the filling time fermented fermentation
~tarter can be pumped into a fermentation chamber at a station
20 time lTaktzeit] t.hat equals the filling tlme. Still more
additive~ are added in the fermentatiorl chamher, and the finlshed
leaven iB made.
A further possibility for reducing the ripening time o~
the leaven is to enhance the growth rate of bacteria by the
addition of micro-organlsms (DE-AS 12 41 382). In this way,
leaven can be produced continuously at an increase throughput
rate. In order to prevent similar negative effect that is similar
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21421-259
-to that seen when the temperature i.s increased, a considerable
outlay with respect to monitoring technology is required for this
process.
DE-S 1018363 describes a process of this kind that is
used to produce leaven, ln which a plurallty of fermenters are
connected in stages and in which the leaven is advanced to the
outlet of a parkicular fermenter by the pressure that results
during fermentation. Because of the activation of the
fermentation process, which is dependent on environmental
conditions (temperature, humidity), there may be variations in
both throughput and quallty, whlch are caused by the tlme o~ year,
when ~his process ls used.
Furthermore, only large quantities of leaven can be
produced economically using the known processes and devices. This
disadvantage is particularly plain during continuous operation of
baking systems, ~hen they are operated during the night as well,
for each tlme the leaven has been produced, a large quantity of
leaven has to be baked withln the relatlvely short storage life of
the leaven. Matching the prepared quantities of leaven to the
actual quantities of leaven required for baking, and the provision
of such leaven ls particularly difflcult because of this.
It ls the task of the present invention to describe an
economical process for producing leaven by whlch a predetermined
quantity of leaven that is matched to the baklng ou~put oi the
baklng systems without any of the effects caused by changing
envlronmental conditions can be made avallable. Furthermore, a
simple and easy to operate system for producing leaven, in
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21q21-259
particular one that is sultable for carrying out this process, and
that is of sufficient quality for baking can be removed a~ any
time in sufficient quantities, is also described.
According to the present lnventlon, thls problem has
been solve~, wlth respect to the process, in that the leaven
preparatlon that is mlxed into the first fermenter and contalns
all the requlred addltives is passed, after the explry of pre-set
station times that are the same for all the fermenters within the
fermenter chain, into the next fermenter in the fermenter chain,
and after passing through the fermenter chaln ls moved into a
storaye contalner.
Uslng this process, it is possible to produce natul-al
leaven without t~e addltion of chemlcal or biologlcal agents
almost continuously, ln pre-determined quan~itles, and at the same
time maintaln the ripenlng tlme that is ln each instance requlred
to ensure that the leaven ls of a high quality.
After fllllng, the leaven preparation, whlch contalns
all the required additives, remains for a speclfic statlon time in
the flrst fermenter. After thls first fermentation time, the
leaven 1~ placed in the followlng, second, fermenter ln the
fermenter chaln, where it remalns for the same station time, untll
lt ls transferred lnto a third lermenter ln the chaln. In this
way, the leaven is moved alon~ the fermenter chain ln a cycle, and
once the ripenlng time for the leaven is over, it is moved from
the last fermenter in the chaln into the storage container. This
produces leaven that is more amenable to storage, the quality of
which can be ~reatly improved by matching the station times for
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21421-259
which lt stays ln the indlviclual contalners to blologically
optimal conditions.
As soon as the leaven has been moved from the flrst
fermenter into the second, the flrst fermenter can be refilled
with new leaven preparatlon, which then passes through the
fermenter chain in the fiame way, 50 that a fresh portion of leaven
arrlves ln the storage container at intervals of one cycle time.
The cycle tlme, i.e., the tlme for which the leaven
remains ln a fermenter, is determined by ~aking into account the
time requlred for advancing the leaven from the duratlon of the
total ripening time of the leaven divlded by the number of
fermenters ln the fermenter chain. In this way, the time that ls
required for passing through the fermen~er chain ls equal to the
total ripening time of the leaven.
The process can be made simpler to carry out in that the -
maximum dwell time of the leaven in the storaye contalner is equal
to the cycle time. This ensures that the ~torage contalner is
empty when the next preparation portion of leaven is delivered to
it. If the storage contalner is of appropriate dimensions, the
dwell
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time of the finishsd leaven can also be a multiple of the
ripening time.
Production of the leaven can be furthar simplified if the starter
for the leaven, which is mixed into the first fermenter, contains
return mass at the storage container.
The baking characteristics of the leaven can be further improved
if the leaven is cooled after the first cycle time, in particular
as the second half of the second cycle time begins. In this way,
bacterial growth within the leaven is restricted so that the
leaven retains its ability to rise and additional agents such as
yeast, which make the dough rise, can be dispensed with when the
bread is baked.
The device used to perform this task incorporates a delivery
system by which the leaven can be moved positively along the
fermenter chain, and a time control system that, at pre-set
timing intervals, generates a control signal to move the leaven
to the next fermenter in the chain or into the storage container~
Operation of such a system that is used to produce leaven is
particul~rly simple since there is only a filling point for
introducing the leaven preparation and one removal point, namely
the storage container, for the removal of the leaven.
Access to the fermenters that are arranged hetween th~ first
fermenter in t~e fermenter chain and the storage container is not
necessary since the leaven is advanced along this chain by means
of a conveyor system. In addition, the cycle times are
controlled by an automatic time control system so that only a
little time~and few personnel are required to monitor the device.
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WO 92/21244 PCT/EP92/01205
There is no need ~or a separa-te mixing device to mix in and
homogenize the leaven start~r, in that ~he first ~armenter in the
fermenter chain is a mixer. 1~his permits a further reduction in
cost for producing the leaven.
It is possible to avoid the use of chemical preservatives by
mixing scraps of previously baked bread in the leaven starter.
If a portion of left-over bread is to be mixed into the leaven :-
starter in order to improve the keeping qualities of the leaven,
then it is particularly useful if a grinder to break up the left-
over bread be incorporated into the first fermenter.
A leaven with particularly good baking characteristics can be
produced in the device if at least one o~ the fermenters that
follow the first fermenter in the fermenter chain incorporates a
controllable cooling device.
Further simplification and reduction of outlay can be achieved i~
the device incorporates a central delivery system, in particular
a central pump, and the fermenters can be connected to the
central deilivery system through valves. Maintenance and
operation o~ the device can be further simpli~ied in this way. :~
The present inventlon will be described in greater detail below
on the basis o~ an embodiment shown in the drawings appended
hereto. These drawings show the following:
igure 1: a device for producing lPaven by the process according
to the present invention;
Figure 2: a flow dia~ram that illustrates the progress of a
portion of leaven through the device shown in figure 1.
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WO 92/21244 PCT/EP92/01205
The device for producing leaven incorporates a mixer 1,
fermenters 2 to 4, a storage container 5, a first d21ivery pump 6
that is connected through supply lines 6a, 6b between the first
mixer 1 and the second fermenter 2, a second delivery pump 7 that
is connected between the second and the third fermenters 2, 3
through the supply lines 7a, 7b, a third deliv~ry pump 8, which
is connected between the third and fourth fermenters 3, 4 by the
supply lines 8a, 8b, and a fourth delivery pump 9 that connects
the last fermenter 4 and the storage container 5 to each other
through the supply lines 9a, 9b.
Within ~he first mixer 1, in addition to a stirrer la, there is a
disintegrator lb that is used to break up the left-over bread.
The fermenters 2 to 4 and the storage container 5 have, on their
outside surfaces, encircling cooling assemblies 2a to 5a, that are
connected through control lines 11 to a central line control
system 10. (encircling)
The delivery pumps are electrically powered and connected by the
control lines lOa to lOd to the central time control system 10.
When producing leaven with a ripening time tR of 16 hours, flour,
water, and lePt-over bread as a preservative, and a small
quantity of previously prepared leaven are added to the mixer 1
mixed for a short time to form a leaven starter. The mixer is
then stopped and the leaven remains within the mixer 1 for a
first cycle time tl. The beginning of the first cycle time is
picked up by the time control system 10, which after the passage
of the first cycle time tl, sends a control signal to the
delivery pump 6 through the line lOa. The first delivery pump 6
thereupon delivers the leaven from the mixer 1 into the first
fermenter 2 along the supply lines la, 6b.
WO 92/21244 PCT/EP92/01205
As soon as all of thP leaven has been moved from the mixer 1 into
the fermenter 2, a second cycle time t2 begins~ Once this second
cycle time t2 has expired, the time control system 10 sends a
control signal along the line 10b to the second delivery pump 7
and this then moves the leaven from the first ferment~r 2 into
the second fermenter 3.
Then, a third cycle time t~ begins as in the preceding step of
the process, when all of the leaven is moved from the first
fermenter 2 into the second ~ermenter 3.
After the expiry of the third cycle time t3, the delivery process `
is repeated and the leaven is moved by the delivery pump 8 from
the second fermenter 3 into the third fermenter 4 t where the
leaven remains ~or a further cycle time t4.
After this cycle time t4 has expired, the time control system 10
sends the last control slgnal for this sequence along the control
line 10d to the last delivery pump 9, whereupon the leaven is
moved ~rom the la~t ~ermentar 4 into the storags contalner 5.
The leaven can now be removed from the storage container 5 fvr
the duration o~ the cycle time tA in order to be baked.
The storage time within the storage container 5 can be a
multiple, e.g. three times, the total fermentation time, so that
a leaven with better keeping qualities re~ults, the production
conditions for which are optimally matched to the biological
requirements (e.g., to the so-called 9'1ag phase," during which
the multiplication of bacteria begins~ by the time that the
leaven remains in the individual fermenters (2-4), so that the ~ -
desixed quality if ob~ained. The finished leaven losated in the
storage container cannot only be used for baking but it can also
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be used as a starter for the subsequent process of producing new
leaven, so that a feedback is made possibla.
As soon as the leaven has been moved out of mixer 1 into the
~irst fermenter 2, the mixer 1 can once again be filled with the
ingredients for a new batch of leaven, which then passes through
the fermenter chain in the same way.
The cycle times tl-t4, and tA for the mixer, the fermenter, and
the storage container, which are o* equal length, are calculated
as follows~
Ripenlnq ti~e ~or the leaven tR = 16 - 4
No. of mixers ~ number of fermenters (1+3)
As an example, if the ripening time for the leaven is 16 hours,
when one mixer and three fermenters 2-4 are used, the cy~le time
amounts to 4 hours.
IP bacterial growth withill the leaven is to be restricted, a~ter
the ~irst hal~ o~ the second cycle time t2 has expired, the time
control system sends a control sign~l through the control lines
11 to switch on the ~irst cooling aggregate 2ac Then, the other
cooling aggregates 3a-5a are switched on by the time control
system 10 so that the leaven is cooled until the end of khe
~ermenter chain. When this is done, the temperature development
in the fermenter~ and in the storage container are picked up by a
temperature mon~toring system (not shown herein) that controls
the cooling output of the cooling aggregate.
Each o~ the fermenters 2-4 incorporate a stlrrer (not shown
herein) which serves on the one hand to even out tempera~uree
~homogenization) and, on the other, to expel gas bubbles.
