DE1642657B2 - Process for fermenting and maturing a malt beverage - Google Patents

Description

calibrated from about 10 to 24 ° C and has beer produced by methods according to the invention

; in the regulated circulation of the cooling medium on this organoleptic properties, which are essentially

kept the temperature. At this point the borrowed are identical to those of beers,

Yeast is still present in the beer, and u-id the beer which is produced by conventional methods

[l through the system for a period of about 5 it is in the aroma, taste and smell of it

Let circulate continuously for 5 days, actually indistinguishable,

until the diacetyl content reaches a value of The fermentation and ripening process according to the

drops below 0.2 ppm (parts by weight per million) and invention can be controlled by automatic

the acetaldehyde content works down to a value below instruments, so that the operations of 5 ppm decreased. At this point in time, the io is controlled from a central point and if necessary

Beer viewed as fully matured or ready. It can be brought under computer control

it is known that diacetyl has a very bad effect on beer for temperature and flow control

th taste and that its formation as far as possible used technical means lead through itself

should be avoided. An addition of yeast to itself to an automatic control resp. Beer containing diacetyl is often said to be successful- 15 control.

Have removal of the diacetyl taste. The drawing shows a device for

At the end of the ripening process, the temperature control of the B rau method of the invention is exemplified

of the circulating beer to a value of approximately wise.

-2 ^; reduced to ⁰ C O, where they are the ER Referring to the drawing, the wort is approaching with congealing point of the beer. When the beer has been inoculated with yeast, kept in a tank 1, which is not at this temperature, it is placed out of the tank halfway inside a building and coated with a layer of heat insulating material and passed through a centrifuge, around the yeast to remove. Can be discovered after removal. The wort is fed into the tank 1 through the yeast, the beer is prefiltered and fed to an inlet line 2 with carbon and is treated with enzymes or other additives through an outlet line 3, added and finely filtered, the carbonic acid - which set in treatment with the lower end of the tank 1 and then bottled. In some bond stands.

Only one filtering process can prepare the cases. The temperature of the wort is

of the beer may be necessary for shipping. tion and maturation by continuous Umlau-Bci a modified embodiment, 30 furnace of the wort through a heat exchanger 4

when the diacetyl content of the wort controls or controls a value that goes through with the tank 1

has fallen from below 0.5 ppm, the temperature lines 5 and 6 are connected. The seasoning will

to a value in the range from 0 to about 13 ° C. out of the tank 1 through the line 5 by means of a

reduced and preferably continuously withdrawn to about 1.1 to about pump 7, flows through the 3.3 'C, and the beer is at this temperature 35 heat exchanger 4 and is through line 6 to

returned to tank 1 over a period of about 1 to 5 days.

circulated continuously in order to produce the final gas. A coolant is supplied to the heat exchanger 4 old aging or the maturity to deliver. At the end of the fed through a feed line 8 and is through After maturation, the beer is discharged into a line 9 by conventional methods, and the flow of the cooler is treated. 40 by means of the heat exchanger 4 can either By continuously circulating the wort either by hand or by automatically operated (not darv > hl valves set during fermentation as well as maturation can be controlled. The process is the total time for aas Brauver- The delivery line 3 of the tank 1 is with a drive is required to be connected to a period of we- centrifuge 10, which serves to remove the yeast Less than 6 days compared to a period of time 45 can be deducted from the fermented beer, and the beer from 20 to 40 days with a conventional brewing process, the centrifuge 10 is withdrawn through a line 11 degraded. given while the yeast through a line 12

Another advantage of the invention is that it is led away.

that only a single tank for both fermentation and with the line 6 is a panel 13 with automatic Also required for ripening, while the 50 instruments are connected, which monitor an oxygen standard method for fermentation and ripening separate, a knife of the specific gravity Requires tanks. In the usual process, the wort and a temperature sensing element will be absorbed the storage tanks are kept in refrigerated cellars. Furthermore, the panel 13 can be one in the and the cost of manufacturing and installing the line-lying analyzer included to both refrigerated cellars are considerable. In contrast, the diacetyl and acetaldehyde content of the the method according to the invention does not require monitoring of the treated product. The signals That the fermentation and maturation tank within one of these instruments can serve to chilled Building or a basement arranged to control driving variants, z. B. Temperature, and is because the continuous circulation cooling is a program for future operations, e.g. B. The wort is dispensed and centrifuged through a heat exchanger. Under the can. Controlling the computer, the output from the-The continuous circulation of the wort during sen sensors can be saved to as continuous Fermentation and ripening processes create a specific record of the work process to serve Better distribution of the yeast through the wort. If certain trends, e.g. B. gravity, show, so that the yeast cells with the fermentable substrate 65 that the beer is ready to mature, the Comder Wort can be brought into closer contact with the temperature at the right level, which results in a higher degree of efficiency and active. After having reached the right level of maturity gives a more uniform product. That the cycle has ended and the diacetyl and acetic

taldehyde content are within the correct limits, the tank 1 can be automatically emptied and its contents are centrifuged.

To carry out the process, the wort is mixed with the yeast or inoculated with it, and either before the wort is introduced into the tank 1 or when the wort is in the tank 1. The wort is then continuously circulated through the closed system by means of the pump 7 left, which, as explained above, the tank, the line 5, the heat exchanger 4 and the line 6 contains. The flow of the coolant to the heat exchanger 4 is adjusted so that the temperature of the circulating wort in the system to a value between about 7 to about 22 ° C and preferably from about 10 to about 16 ° C is held. If the wort has been inoculated with a basic fermentation yeast, fermentation will take place usually at a temperature in the lower part of the range of about 7 to 22 ° C, generally between 7 and 16 ° C, while, if a brewer's yeast is used to inoculate the wort, a temperature in the upper part of the range in the vicinity of about 13 to 22 ° C during generally used in fermentation.

The yeast enzymes work during the circulation of the wort on the substrate of the wort to be fermented, and the circulation of the wort creates a more intimate one Contact between the yeast cells and the substrate to be fermented.

Diacetyl is a by-product of fermentation and gives beer a buttery taste. Although the carbohydrates can be completely consumed in a short time is a high residual content of diacetyl is detrimental to the resulting beer regardless of maturity on storage. the Decrease in diacetyl content is slower than sugar intake, and an additional one Time is required for the diacetyl content to be enzymatically increased to an organoleptically acceptable level, has generally been reduced below 0.2 ppm (parts per million by weight). It turned out unexpectedly found that by raising the temperature of the fermenting wort after most of the Carbohydrates have been assimilated, the diacetyl reduction phase is largely accelerated can, whereby the storage time in the tank is significantly reduced. The metabolism of carbohydrates Heat generated in the wort increases the wort and increases the rate of reaction of the enzymes contained in reducing diacetyl to natural substances. So if the specific Weight of the circulating wort reaches a predetermined value of below 5 ° Plato and generally reaches a preferred value of the order of 3 to 4 ° Plato, the orbital will of the coolant stopped by the heat exchanger 4, while the circulation of the wort through the continued through the closed system. As the cooling effect has ended, the temperature rises according to the wort, the heat generated by fermentation in the residual extract in the wort gradually on. During this part of the process the wort is at a temperature of at least 2.4 ° C above the fermentation temperature in the range of 10 to 24 ° C and preferably about 15.6 ° C held by a controlled circulation of the coolant to the heat exchanger 4.

At this point the yeast is still in the beer, and the fermented wort becomes a Temperature in the range of about 10 to 24 ° C continuously circulated to mature the beer

5 or to age. During this maturation period: works the yeast goes to enzymatically healthy beer by removing the unpleasant and sulphurous By-products of fermentation in more neutral taste and in more neutral odor components

ίο be converted. The specific time during which the beer is allowed to circulate to mature is generally 2 to 5 days, with the specific Time is determined by the organoleptic qualities of the product. As an index of maturity the fermented wort is allowed to circulate continuously until the diacetyl content has a value of less than 0.2 ppm and preferably well below 0.1 ppm, and the acetaldehyde content the fermented wort decreases to a predetermined value below 5 ppm. If those If values are reached, the ripening process is finished to watch. At the end of the ripening or aging period, the coolant flow is reset, to cool the circulating beer to a temperature in the range of -1.6 to 0 ° C, which Temperature is approaching the freezing point of the beer.

When the beer has reached this temperature, will

the beer is drawn out of the tank 1 through the outlet line 3 and is pumped into the centrifuge 10, wherein the yeast and other components are removed by centrifugation. Deis cooling of the beer to a range between - 1.7 and 0 ° C prior to centrifugation allows for better separation of the yeast and other harmful components.

After centrifugation, the beer is further treated by conventional methods, which are general pre-filtration and carbonation, the introduction of enzymes or other beer additives, Final filtration, final carbonation and transportation to storage tanks prior to packing contains. Both filter runs can be carried out in a single process, as the yeast centrifuge does essentially removes the yeast and foreign components, which is usually done by prefiltration removed.

In some cases, the yeast can be removed from the wort after fermentation and before maturation. In this case, the fermented wort is pumped from the tank 1 into the centrifuge 10, and the Clarified wort is then returned to the tank for the ripening process. In this modified one In the process, the greater part of the yeast is removed by the centrifuge, using a yeast concentrator of about 6,000,000 yeast cells per mm of wort and the remaining yeast cells work to make the beer during the aging process to mature zymatically. However, it is preferred to choose the original yeast concentration in the beer end of the ripening process because: the mechanical stage of centrifugation between the fermentation and the ripening are eliminated and a <larger amount of yeast to speed up the enzy matic maturity of the beer during the maturation or aging process creates. As stated above the ripening is carried out for a period of about 1 to 5 days. However, if part of the de Yeast is removed before ripening can prevent ripening

pciiode on 15 or 30 days without any adverse Effect on the beer can be prolonged, however, such a prolonged maturation period improves the organoleptic properties of the beer are not noticeable and have from a practical point of view from the point of view no advantages.

The rate of flow of the wort through the system during the fermentation and ripening processes is not particularly critical. However, should the flow of the wort should be continuous, and usually the flow should be such a speed have that the entire capacity of the tank 1 is moved at least once every hour. For example, if If the tank has a capacity of 49,200 1, the flow rate should be at least 49 200 1 per hour.

The beer can be kept in a tank during maturation or aging so that it does not circulates through a closed system, as shown in the drawing. In this case it will Beer is continuously moved or stirred to achieve the desired intimate contact between the yeast cells and the beer. Hence the term "moved" as it is used in the present context is used to mean pumping, stirring, or any other means which keep the yeast in suspension in the beer.

In another embodiment of the invention, the ripening is carried out at a somewhat reduced temperature compared to that described in the first embodiment. As in the first embodiment, the flow of coolant to the heat exchanger is adjusted so that the temperature of the wort circulating in the system is maintained at a value of about 7 to 21 ^c C until the specific gravity of the circulating wort is below a predetermined value 5 ° Plato and generally a value in the range of 3 to 4 ° Plato. When this specific gravity is reached, the circulation of the coolant through the heat exchanger 4 is stopped, while the circulation of the wort through the closed system is continued. As the cooling effect has ended, the temperature of the wort gradually rises due to the heat present in the wort due to the fermentation of the residual extract. The temperature of the wort is kept at least 2.4 ^D C above the main fermentation temperature and in the range from 10 to about 24 ° C, preferably at about 18 ⁰ C, by the controlled circulation of the coolant to the heat exchanger 4.

When in this process the diacetyl content of the wort falls below a predetermined value 0.5 ppm reduced, the coolant is supplied to the heat exchanger 4 at a rate which is sufficient to bring the temperature of the circulating fermented wort to a value of 0 to about 13 ° C and preferably at one temperature between about 1.1 and 3.3 ° C. The wort is at this temperature during a Period of 1 to 5 days circulated continuously by the system and this depends on the organoleptic properties that are desired in the end product. When the acetaldehyde content of the wort to be fermented falls to a predetermined value below 5 ppm, the Ripening process regarded as finished. At the end of the ripening process, the flow of coolant will be like this set so that it cools the circulating beer to a temperature in the range of about - 1.7 to 0 ° C, which is approaching the freezing point of beer. Then the beer is withdrawn from the tank and centrifuged and processed further as described with reference to the first embodiment.

example 1

About 49 200 l of wort are introduced into a tank and mixed with a ground yeast for fermentation. The tank is connected to a closed flow system with a heat exchanger. The wort runs through the heat exchanger at a flow rate of about 49 200 liters per hour and the flow of coolant to the heat exchanger is stopped, around the temperature of the circulating wort

so keep around 13 ° C. The seasoning is based on a specific one Weight of 4 ° Plato fermented, which takes about 2½ days. Once that specific Weight is reached, the flow of coolant to the heat exchanger is interrupted,

»5 while the flow rate of the wort is maintained by the circulation system at 49 200 liters per hour. The temperature of the wort rises as a result of the heat generated by fermentation slowly to around 16 ° C and is controlled by a The flow of coolant is maintained at this temperature through the heat exchanger.

The fermented wort is circulated at this temperature until the acetaldehyde content is 3 ppm reached and the diacetyl level falls below 0.1 ppm, which requires a period of about 4 days. That Beer is then cooled to a temperature of around -1.7 ° C and turns into a from the tank Centrifuge pumped where the yeast is removed. The centrifuged beer is then brewed by standard brewing methods treated.

Example 2

49 200 1 wort are introduced into tank 1 and inoculated with yeast. The wort is circulated through the heat exchanger at a flow rate of 49,200 per hour and the flow of coolant to the heat exchanger is adjusted to maintain the temperature of the circulating wort at about 13 ° C. The wort is fermented to a specific gravity of 3.5 ° Plato, which takes about 2Vs days. As soon as this specific gravity is reached, the flow of coolant to the heat exchanger is stopped while the flow rate of the wort through the circulation system is maintained at 49,200 per hour. The temperature of the wort rises to a maximum of about 19 ^° C. as a result of the heat generated by the fermentation. As soon as the diacetyl content reaches the value of 0.2 ppm after about 1/2 days, the coolant is fed to the heat exchanger at a rate which is sufficient to reduce the temperature of the circulating wort to a value of about 2.2 ° C permit. The fermented wort is converted at this temperature

allowed to run until the acetaldehyde level reaches 3 ppm, which takes about 1 day. The beer is then cooled to a temperature of around -1.7 ° C and fed from tank 1 to a centrifuge

509533/151

directs where the yeast is removed. That centrifuged over the temperature of the wort in the system

Beer is then obtained using standard brewing methods.

acts. Bacteria tend to make rancid products

The method of the invention has advantages over producing bad taste, which the known continuous fermentation processes change decisive organoleptic properties of the beer. Known continuous fermentation can, and the method of the invention verminverfahren require a continuous supply of other due to a substantial reduction in the lingering wort, whereby a microbiological time of the product in the system against the contamination and destruction of the usual brewing process can largely be possible . The known methods require a high concentration of yeast which is found in the fermentation tank. As a further advantage, the physical properties of the wort, e.g. B. specific gravity, the development of yeast-containing temperature, diacetyl content, oxygen content thereby u. The like., And of substances with bad taste in the results _in a flowing medium as in the process of beer, the i is not eliminated in the ripening process ₅ present invention easier than in a stawed. In addition, the continuous bodies need to be determined in which a lent fermentation process of this kind complicated stratification occurs. The more precise analyst control systems to maintain the product uniformity readings result in a more precisely controlled, and more cooked product required

temperature which leads to the development of un- * “The process is particularly suitable for itself

contribute to the desired bad aroma ^ self-regulating instruments, if necessary to one

The method of the invention avoids post-computer control. The signals from the analysis parts of the known methods by continuous instruments on the panel 13 can serve to circulate a given amount of wort both the variables of the process, ζ. Β temperature Sauwahrend of Garungs- and the Reifungsvorgan- * ₅ erstoffgehalt, as well as the control and ges and generates a beer to control which completely accepted programming operations table organoleptic properties ha Furthermore, _{it has been a Rdh vol} f _Bi | _{The time required} for the circulation garunes and _llm hip ηΐιυ «ι- ·>ι; οΐ, c · ι« "« »j ³ ^"s> ripening process jtaWtt., ta whose % ££% ££ ^ f £££? 45l

but the assumption that the end product * free / on ^ SS ^ Ä * "* ^ *""""" °° bad aroma and taste and equal to the T _{n of} the TaK _P ii » u ■ u j · _π ·. _{,, u} -

Beer is which has been produced in partial quantities by the usual Gämngs- and _{Nr 4} beers Se l _Pm R i ^Π \ "; ίΐ ^ΒκΚ u * Ä 'ί maturation method. 35 resourceful he ^ tefh T \ η ^V ^ ^{en after the} ^ l

When applying the method of the invention Se wu _r of the _U w £ h W "™ ^{producible g,} only a single tank for fermenting and storage B is auhefe with sner K * ™ u ^

In contrast to the usual procedures, toes per cm «ver _Se tzf ^" are ^required

which have separate tanks for fermentation and storage R _P , Hem n: „κτ, Ί,,. "

As a result of the accelerated fermentation and ripening, 40 Tem er2 ία 13 i Λ? ' the flavor of one and as a result of the fact that only a single tank gunT by uSaufenlaL ™? ¹ ^ T ^ is required, the total tank volume or Shlossenes FlkßsvsferT

the capacity for a given beer output to ^^^^ S ^^^^. Ve compared to that of a conventional brewing process _eor en what about τι / τ, ■ α, '5 \, u

reduced. ₄₅ of the Gämno w nj _P H ⁸ ^ '' ^ P ™ * "^ m on the number of tanks, a considerable saving is 15 85 ° C erhöbt Ih ^ ^{Tem perature} errekht ^to approximately to work because it is necessary by reducing the presence erforderüchen is to clean every tank Jie yeast enfhtlt wil ^ ΎΎ ^^^ after pumping. Another advantage of L? 1St ΐ, ° ^ntmu i? ^{rhch By J} is achieved cost savings in cleaning chemi- emeTw ^ TES Z ^ ft ^ ^ ^"Fbdis ^ ^m ^ Hen because fewer tanks and pipes ₅ o Sid, S ^ ΪΓβ ™ about 3Tagen kontinach any promotion must be lereinigt.? SSS Res, ZT ^ 5? ^mature · ^After ^ ***

The reduction in the tank volume diminishes abSen SH ^ e η I ^ ^ ^ "^ f" continues the capital investment 'and the maintenance St S Br Sh ^ Z ^ tafiigieiai peeled off to a ^ ert vo ^ about V. emes usual ^^^ Γ ^ ΐΐΓ ^ "* ^ procedure and in a corresponding way 55 never Bien» Nr ο ι! Γ 7 * losses or handling losses by the same way heS ^ triit '·. J ™ a ⁴ ^^ " ⁱⁿ ^

Chen factor, e.g. B. Shrinkage resulting from leaks, Nr T fad one! \ Except that the beer

by residues in pipes and tanks results in fermentation un5 L Sf? "' ^W ^^^ JJ ^C , this depends on the number of tanks, the connections and the I ₈ 1 ° Γ" ^ V ®? temperature of the production. 6 “TemDera ^ vn * l ^{Wd the beer Nn 4 Μ etae} ?

It's not necessary! the tank in a refrigerated 2? T ^ cZTlt ^ -i '**? '"5SSZ ** ^ th cellar or a chilled building, as in w ^ rde d! En ί approximately 16.95 ° C matured the usual procedure, since the wort natures per" S · ^ ^Γ ? ^{ε at the} S ^ ^{eichea Tem} "fermented by circulating through the heat exchanger and grabs" ⁸ ^ ^{dCm beer ΝτΛ} ** is cooled. The tank can either be within a 65 It were «to α α η- «

Beers No. 1 ^ ™ * · ™ «« ™ ^ »«! be with regard to net and is preferably with a heat- kaiischen FiaencS? r * * 'λ ^from ? ^{e leads} ' ^{and ώε} P ^h y?' insulating material coated to better control indicated " ^{Blere smd m the tabdle}

ii

The beers No. 1 to No. 4 produced according to the method of the invention are in theirs Quality equivalent to a normal beer, which is assumed to have the same flavor.

A fermentation of a wort of the kind used to make heavier beers or ales at 19 ° C and maturation of the fermented substrate at a temperature of

23 ° C produces a beer that is equivalent in quality to usual heavy beers and ales.

Using the method according to the invention, however, a beer is produced which is more uniform from batch to batch than is possible with the known method. In addition, the Biei generated in a much shorter dwell time.

Beer No. 1 Beer No. 2 Beer No. 3 Beer No. 4 Fermentation temperature, ° C 13.30 15.0 13.30 14.40 Maturation temperature, ° C 15.85 18.1 15.85 16.95 Analyzes Beer color (° Lov. 52-1 / 2 "Cell) 2.1 2.3 1.7 1.7 Apparent extract, ° / o 2.22 2.24 2.35 2.34 Alcohol, percent by weight 3.82 3.79 3.65 3.64 Actual extract, ° / o 4.0 4.01 4.05 4.08 Beer protein (N ■ 6.25), ° / o 0.27 0.29 0.24 0.24 Beer, pH 4.0 4.0 4.0 4.05 Beer calcium, ppm 39 38 76 61 VDK, ppm 0.03 0.03 0.06 0.06 Isohumulones, ppm 14.9 17.0 12.5 12.8 Original extract (calc.) 11.44 11.39 11.16 11.07 Air content, ml / 340 g beer 1.40 1.25 0.32 0.50 C0 ₂ volume 2.70 2.66 2.69 2.58 Clarity (clarity standard) 0.5 0.5 0.5 0.5 3 day rotator - 23.9 ° C 0.91 0.94 3.5 4.0 Oxalate, ppm 4.0 4.0 4.5 4.0 For this 1 sheet of drawings

Claims (5)

1 2 top-fermenting fermentation process studied in which several patent claims: z. B. 2 to 3 vessels were used, with fermentations of 25, 50 and 70 to 75%> in each vessel 1. Procedure for fermenting and maturing a barrel take place. The fermentation was carried out by the Ge malt beverage, whereby a wort containing yeast was controlled at 5 G speed of the wort inflow, the vessels at a temperature in the range from about 7 to were provided with agitators. 21 ° C is continuously moved to the yeast. The process works according to a similar principle. to keep in suspension, and then tire drive by Morton W. Courts, in which usually two is left, characterized in that fermentation tanks are used, which are equipped with external dimensions the main fermented wort is provided with a temperature cooling. The wort is stored in the storage tank Cooled from at least 2.4 ° C above the main tank to 0 ° C and left to ferment at temperature for 48 hours and in the range from 10 to sen, so that the turbidity and the protein substances from -24 ° C under one to keep the yeast in suspension and to be able to settle. Then the seasoning the continuous movement is matured. from below into the first fermentation tank, where through 2. The method according to claim 1, characterized in that the yeast is kept in suspension and an agitator indicates that the temperature of the main fermenting wort ferments quickly. Depending on your needs, the Fermented wort by keeping temperatures between 5 and 25 C during the fermentation process Heat to the ripening temperature increases the. By the concentration of the yeast that will ferment. temperature and the speed of the flow 3. The method according to claim 1 or 2, characterized sto the degree of fermentation of the beer, the above from characterized in that the fermented wort flows off the tank, regulated. Matured for a period of 1 to 5 days. According to H. J. Wellhoener, the will. Main and secondary fermentation. In the three larger areas 4. The method according to any one of claims 1 to 3, contain the in a higher-lying room under it marked that the wort are brought through 25, takes place at approximately 12 ° C Circulating through a plant with geschios main fermentation, in the three others, among them sifted Cycle is moved. stored vessels takes place at 0 ° C cellar temperature 5. The method according to any one of claims 1 to 4, the secondary fermentation. The main and secondary fermentation are therefore permanent marked that the fermentation and the th approximately 18 days. Matures can be run in the same vessel. The object of the present invention is to provide a process in which both fermentation and maturation of a malt beverage, such as beer, take place. det and in which the fermentation in particular in one single fermentation tank takes place and no special cooling 35 basement are necessary. The invention relates to a method for The object according to the invention is achieved by a Fermentation and maturation of a malt beverage. Process for fermenting and maturing a malt beverage, With common brewing methods, wort is made with yeast. wherein a wort containing yeast is mixed at one temperature or inoculated and then continuous for a time temperature in the range from about 7 to 21 ° C is moved from about 3 to 15 days in a fermentation tank to keep the yeast in suspension, during which time the yeast enzymes are released and then allowed to mature, let the sugar work in to ferment the wort. Which is characterized by the fact that the main customary Practice during fermentation consists in fermenting wort at a temperature of at least the wort without agitation in a static addition- 2.4 ° C above the main fermentation temperature and thereby to withstand, although in some fermentation processes 45 in the range of 10 to 24 ° C below one the yeast the wort can be moved slowly by stirring in suspension maintaining continuous agitation can. After fermentation, the yeast is allowed to mature. set, and the fermented floating over it in the practical execution of the process Wort is pumped into a storage tank which, according to the invention, is e.g. B. the wort is placed in a refrigerated cellar, and introduced during 50 tank and inoculated with yeast. After a period of 7 to 30 days at a temperature of yeast, the wort from the tank is stored at a temperature of about 0 to 7 ° C. A small amount of yeast circulating continuously in a heat exchanger is left in the fermented wort and suspended in the tank in a closed tank and carried away with it. Recirculated during this flow system. The beer is again supplied to the heat accumulation storage period in a static 55 a coolant is supplied to keep the wort schem state without moving, and during fermentation at a temperature in the residual yeast works to the beer enzymatically too rich of about 7 to keep up to 21 ° C,
mature and the undesirable by-products of when fermentation has advanced to a point- Fermentation in more neutral tastes and smells is at which the specific gravity of the wort convert components. Therefore, the 60 insists on a predetermined value below 5 ° Plato Brewing is the well-known practice in which the wort falls off, adding the coolant to the brew rend of fermentation and ripening in a substantially heat exchanger, and the temperature borne static state, because one of the fermented wort, which took inside the closed, that movement would contribute to the revolving system is due to the effects of the Beer bitter properties heat generated by autolyzed yeast 65 fermentation gradually increased. the granted. The temperature of the fermented wort may rise, According to "Brauwelt", 101 (1961), No. 78, p. 1847, until it reaches a value of at least 2.4 ° C above Hough and Rudin have one of the main fermentation temperatures on a laboratory scale and generally in the