High temperature wort thermal treatment system and method

Abstract

The present invention relates to an energy efficient continuous wort thermal treatment process and system, comprising: a feeding pump for feeding incoming wort via a feed line, a heat exchanger being fluidly connected to the feed line and arranged to heat the incoming wort, a holding cell, into which the pre-heated wort is fed and held pressurized for a specified time period at a determined pressure and temperature, which is below a boiling point of the wort at the determined pressure, wherein the wort is held pressurized by means of the pressure generated by the feeding pump, and wherein the heat exchanger is arranged to receive the heat-treated wort from the holding cell, the heat exchanger arranged such that the heat-treated wort pre-heats the incoming wort to a target temperature, and the incoming wort cools the outgoing heat-treated wort.

Description

[0001] High Temperature Wort Thermal Treatment System and Method

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to the field of brewing and more specifically to wort boiling technology. More specifically, the present disclosure relates to a process for continuous wort thermal treatment in a beer brewing process and to a continuous wort thermal treatment system, as further defined in the preamble of appended claims.

[0004] BACKGROUND

[0005] Wort boiling is an energy-demanding operation in brewing and can account for around 40% of the total energy use in the brewery. Wort boiling is traditionally done by boiling in batch under atmospheric pressure for around 70 minutes. Energy recovery systems can be used to condense the generated vapors to recover energy.

[0006] Three of the main process goals of the wort boiling are to isomerize hop substances, coagulate proteins and to eliminate off-flavors. Especially, S-methyl methionine (SMM) is converted to dimethyl sulfide (DMS) that is then being removed via vapors during evaporation. In the processes for wort boiling known in the prior art, evaporation of undesirable substances, in particular free DMS, is therefore aimed at. For this purpose, the free DMS present in the wort is evaporated and expelled in the wort kettle with rest of the vapors generated by the boiling process. The boiling system may be for example an internal or external boiler. Another example of removal is use of flash evaporation with a high temperature boiling system.

[0007] During the removal of hot trub, for example by means of a Whirlpool, new free DMS can be formed due to the relatively high residual temperature of the wort in the range of > 80°C and the presence of SMM, which is traditionally not expelled again, if a Whirlpool is used for removing the hot trub. In the prior art, systems are known which provide evaporation by expansion into a vacuum, a stripping process, optionally supported by gas streams which are preferably conducted in opposite directions, or via an evaporation process. High temperature wort boiling is a known technique in the field. The principle is to bring wort under pressure in a holding cell to about 130-140°C, where the DMS conversion, coagulation of proteins and isomerization processes can take about 2 - 4 minutes. The removal of the DMS in the process is then done by flashing, i.e. releasing the hot wort at 130-140°C in an atmospheric tank, which generates a lot of vapors and therefore strips the DMS. The problem with the above-mentioned technologies is that because of the evaporation process, despite energy recovery system requiring storing of the recovered energy in an external medium such as water, the energy losses are high. Another problem is that recovering energy from vapors via condensation implies a higher energy loss.

[0008] Another method known in the art to lower energy consumption is to keep the wort at 100 degrees without boiling, therefore avoiding the energy use to evaporate. The wort is then stripped in a stripping column with gas, for example CO2, N2 or air. Stripping with gas is a very efficient way to remove DMS with low or no energy demand. However, the method requires long time, provides lower isomerization rate and thus different wort quality.

[0009] A prior art document DE102014104899A1 discloses a method and device for treating wort in beer production process comprising boiling wort and keeping it hot in a container under pressure, cooling the wort to a temperature below boiling temperature at atmospheric pressure and evaporating undesired substances from the cooled wort. In the process, thermal energy contained in the wort can be transferred to a heat exchanger by transferring the thermal energy to a cooling medium, in particular a liquid cooling medium, which is correspondingly passed by the heat exchanger. However, the use of cooling medium to convey and store energy requires use of two heat exchangers: one to take the energy from wort to water, and another to convey the energy from water to wort. Therefore, there are energy losses in the total energy recovery.

[0010] A further example of a prior art process is shown by GB2182672A. According to the document, the beer wort incoming from a mash filter and extracting unit or from a receiver, the temperature of which is about 70-73 degrees Celsius, is pumped continuously with pump a regenerative heat exchanger, where the beer wort is heated up to 80 degrees Celsius. Afterwards the beer wort goes to a plurality of steam / liquid heat exchangers, where it is successively heated up to 120-125 degrees Celsius by the steam coming from the steam reducers arranged in series. The heat exchanger used is a specific type of regenerative heat exchanger taking advantage of condensation of steam in two stages. In the first / last heat exchange step a regenerative heat exchanger mounted before the heating steam / liquid heat exchangers is used to heat the wort. A side of said regenerative heat exchanger is connected to the pipe of the incoming beer wort and the other side thereof is connected to the fluid outlet junction of the last pressure reducer. The solution is space-requiring is not easily adjustable to different conditions. Further, the system requires three stages of pre-heating of which two are based on heat recovery by condensation, therefore implying the requirement for flashing or boiling process requiring a substantial amount of energy to reach the wort boiling temperature and implying an unavoidable cumulative energy loss of the three heat exchanger stages.

[0011] In the above-mentioned prior art devices, heat is first transferred from a hot medium to a storage material and then transferred to a cold medium This type of heat exchanger requires temporary storage of the heat transferred, and therefore requires multiple steps and complicated system structure, as in DE102014104899A1 , or require the use of condensers implying a greater energy loss through the inherent difficulty of recovering energy via condensation as in GB2182672A.

[0012] Thus, despite existing solutions to reduce energy consumption in wort boiling, there is still room for improvements.

[0013] SUMMARY OF THE INVENTION

[0014] In view of the environmental requirements and global goals for reducing energy consumption in industrial processes, it is an objective with the present invention to provide improved reduction of energy consumption in the so-called wort boiling process, while still providing high efficiency in the reduction of off-flavors. Especially, it is an objective of the present invention to keep the advantages and remove the disadvantages of the prior art techniques.

[0015] The objectives above are attained by the present invention as defined in the appended claims. According to a first aspect, the objectives are attained with a process for continuous wort thermal treatment in a beer brewing process defined in the independent claim 1. The process comprises the steps of:

[0016] - providing incoming wort into which hops have been added at a temperature of 50 to 90°C, or 60 to 85°C, or 70 to 80°C, or between 72-78°C,

[0017] - feeding the incoming wort to a heating step by means of a feeding pump,

[0018] - heating the wort to a target temperature of 110-150°C, or about 125- 140°C, at a determined pressure, wherein the temperature is below a boiling point of the wort at the determined pressure,

[0019] - supplying the heat-treated wort to a holding cell and pressurizing the wort to the determined pressure in the holding cell by means of the feeding pump,

[0020] - keeping the heat-treated wort pressurized at the determined pressure and at the target temperature of in the holding cell for about 100s to 600s, or 120 to 300 s, or 150s to 210 s,

[0021] - supplying the heat-treated wort from the holding cell back to the heating step, in which the heat-treated wort is arranged to pre-heat the incoming wort, and the incoming wort is arranged to cool the heat-treated wort.

[0022] The pre-heating of the incoming wort and the cooling of the outgoing heat-treated wort is arranged as a wort-to-wort heat exchange in the heat exchanger without using an additional heat exchange media, preferably in a counter current way to maximize heat transfer. Thus, no separate cooling / heating media is needed, and the heat recovery is done in one step.

[0023] The claimed process is continuous. The wort is kept pressurized in the holding cell by the feed pump and at a set temperature close to but below the boiling point of the wort at the set pressure. Therefore, the boiling phenomenon is avoided. The quality of the wort can be kept high, while the energy demand is kept low since there is no boiling and evaporation during the required thermal treatment of the wort. Thus, there are no energy losses due to the evaporation as the treated wort comes out of the system under pressure and at a temperature below the boiling point at atmospheric pressure. As the outgoing heat-treated wort pre-heats the incoming wort, it is possible to reduce steam consumption for the heating. Furthermore, effective cooling of the outgoing heat-treated wort can be obtained in one step. Thus, energy demand can be considerably reduced compared to the prior art solutions, in the range of 80 to 90% less compared to a conventional wort boiling system The thermal energy recovery rate for the thermal treatment of the wort can therefore be very high, such as in the range of 90 to 96%.

[0024] The incoming wort can be pre-heated by the heat-treated wort from the holding cell to a temperature, which is less than 10°C, or between 2 to 5 °C, from a target temperature at the determined pressure. The heating step may additionally comprise heating the incoming wort to the target temperature at the determined pressure by using steam for the heating. However, the use of the steam can be reduced in heating to the target temperature, since the wort has been pre-heated.

[0025] The incoming wort may be arranged to cool the heat-treated wort from the holding cell to a temperature being 1-10°C, or between 2 to 5 °C, warmer than the temperature of the incoming wort. In this way, no separate cooling media or cooler needs to be used after the heat exchanger to recover most of the energy required for the thermal treatment of the wort.

[0026] According to another aspect of the invention, the objectives mentioned above are also attained by a continuous wort thermal treatment system comprising:

[0027] - a feeding pump for feeding incoming wort via a feed line,

[0028] - a heat exchanger unit being fluidly connected to the feed line and arranged to heat the incoming wort,

[0029] - a holding cell, into which the heated wort is fed and held pressurized for a specified time period at a determined pressure and temperature, which is below a boiling point of the wort at the determined pressure, wherein the wort is held pressurized by means of the pressure generated by the feeding pump, and wherein

[0030] - the heat exchanger unit is arranged to receive the heat-treated wort from the holding cell, the heat exchanger arranged such that the heat-treated wort pre-heats the incoming wort to a target temperature, and the incoming wort cools the outgoing heat-treated wort.

[0031] The pre-heating of the incoming wort and the cooling of the outgoing heat-treated wort may be arranged as a wort-to-wort heat exchange in the heat exchanger without using an additional heat exchange media. The heat exchange is preferably arranged in a counter current way, to maximize energy transfer. In this way the system can be made compact, and a very high energy recovery rate can be obtained.

[0032] The heat exchanger may be fluidly connected to a steam generator arranged to additionally heat the pre-heated wort to the target temperature at a determined pressure. Since the wort is pre-heated, the amount of steam required for the heating can be considerably reduced, whereby further energy savings are achieved.

[0033] The steam can be replaced by other heating medium such as super-heated water or direct electrical heaters.

[0034] The heat exchanger unit may be a plate heat exchanger. By the plate heat exchanger, a very high energy recovery rate can be obtained. The heat exchanger may comprise a first section arranged to pre-heat the incoming wort and cool the heat-treated wort. The heat exchanger may comprise a second section, which is fluidly connected to the steam generator arranged to additionally heat the pre-heated wort to the target temperature at the determined pressure. The heat exchanger unit may further comprise a third section arranged to further cool the heat-treated wort. In this way the wort flows can be arranged inside the heat exchanger in a space-saving and efficient manner.

[0035] The system may further comprise an atmospheric whirlpool tank, in which coagulated proteins are separated. The system further may also comprise a stripping column fed with air, CO2 or N2 for the removal of DMS. The atmospheric whirlpool tank can be located upstream or downstream of the stripping column. The whirlpool and the stripping column may be arranged to receive the wort in a continuous manner.

[0036] SHORT DESCRIPTION OF DRAWINGS

[0037] Reference is made to the following drawings, in which the invention is further described. In the drawings:

[0038] Fig. 1 shows schematically an example flow scheme of the heat recovery part of the present invention,

[0039] Fig. 2 shows schematically another example of a flow scheme of the heat recovery part of the present invention,

[0040] Fig. 3 shows a further example of the flow scheme of the heat recovery part of the present invention including a plate heat exchanger device with energy recovery part and the pre-cooling part.

[0041] DETAILED DESCRIPTION

[0042] Reference is made to the appended drawings, and to Fig. 1 , which shows a system suitable for providing the continuous wort treatment process with energy recovery in a beer brewing process according to the present invention.

[0043] Wort can be provided in a manner known to a skilled person. It can be provided by a process including crushing and mashing barley with water referred to as a mashing process. The sweet wort is then obtained by filtration of the mash. The sweet wort is then boiled to achieve desired taste and quality properties. During wort boiling bitter hops substances are dissolved and isomerized, proteins precipitated, and aroma and color components formed. Additionally, microorganisms and enzymes can be inactivated. In the present application, by wort boiling is meant thermal treatment of the wort, in which the above-mentioned same effects as with traditional boiling at a boiling temperature at atmospheric pressure are achieved. During the thermal treatment, a higher pressure and higher temperature than the atmospheric pressure and boiling temperature at the atmospheric pressure can be used. The wort will then reach the effects without essentially forming bubbles and therefore avoiding the boiling phenomenon, nor requiring flash evaporation. As described above, the boiling process or thermal treatment may also form undesirable aroma substances. These undesirable substances need to be therefore expelled or removed from the wort during and / or after boiling or thermal treatment of the wort, by for example a stripping process. In the stripping process the undesirable substances are removed from a liquid stream by a vapor stream, i.e. for examples steam. The proportion of free dimethyl sulfide (DMS) is generally used as a reference for successful expulsion of undesirable substances from the wort in beer production. 100 pg per liter is usually regarded as a recognized limit value for an acceptable proportion of free DMS in final beer. As explained above, the wort boiling to evaporate off-flavors demands a lot of energy. By the present invention the energy consumption can be significantly reduced while minimum number of changes to existing brewery processes is required.

[0044] In the beer brewing system 100 according to the present invention, an example of which is shown in each of Fig. 1-3, the wort 10 can be provided according to a manner known to a skilled person in the field and as explained above. The incoming wort 10 is supplied to the continuous wort treatment system via a feed line 12 and hops 20 can be added to the wort in the feedline 12 upstream of a heating step. The wort may be relatively clear, and the hops may be added as an extract. The wort 10 including the hops 20 is then pumped by means of a low-pressure pump 30 to a heating step. The low-pressure pump may be of any suitable type and may be operating at a pressure level of for example up to 10 bar gauge pressure. The incoming wort before the heating step may have a temperature of about 50 to 90°C, or 60 to 85°C, or 70 to 80°C. Suitably the temperature can be between 72 and 78°C. In the heating step, a heat exchanger unit 40 is utilized. The heat exchanger unit 40, herein also referred to as an energy recovery unit 40, may comprise one or more heat exchanger sections. Each of these heat exchanger sections suitably comprise or consist of plate heat exchangers having separate flow paths for each fluid, which fluids flow simultaneously through the heat exchanger, exchanging heat across a wall separating the flow paths. The heat exchanger may be of any type of a plate heat exchanger, such as gasketed plate heat exchanger. Plate heat exchangers comprise several heat transfer plates which are held together by a fixed plate and a loose pressure plate to form a complete unit. Each heat transfer plate may have a gasket arrangement providing two separate channel systems for the colder and warmer fluid, respectively. The fluids are arranged to flow in a counter-current flowing manner and are not mixed due to the gasket design. The plates may have a corrugated structure, whereby turbulence is created in the fluids when they flow through the plate heat exchanger unit. This turbulence improves the heat transfer between the fluids. The plate heat exchangers have several advantages: They have a high heat transfer efficiency, and the energy recovery level can be up to 95%, making plate heat exchangers superior compared to regenerative heat exchangers using a storage media for the heat exchange. Thus, the plate heat exchangers do not require any intermittent storing of the heat before it is transferred to a colder fluid. Further, the structure is flexible and can be adapted to different processes in a space saving way. For example, the plate heat exchanger may be arranged with multiple sections, for example for the recovery of heat and cooling, as also shown in Fig. 3. The plate heat exchangers are easy to clean and individual plates can be removed from a plate pack. Furthermore, the plate heat exchangers can be pressurized.

[0045] Returning to Fig. 1 , the heat exchanger unit 40, also referred to as a heat recovery unit, may comprise a first heat exchanger section 41 a second heat exchanger section 42. A third heat exchanger section 43 may be included and is shown and further described in the example of Fig. 3. The incoming wort can be guided through the energy recovery section 41 of the heat exchanger 40 and then the heat exchanger section 42 in Fig. 1 and heat-treated to a target temperature of 110- 150°C, or about 125-140°C at a determined pressure. The temperature can be chosen to be below a boiling point of the wort at the determined pressure. The determined pressure may be over atmospheric pressure, i.e. the wort entering the energy recovery section 41 of the heat exchanger unit 40 may be pressurized up to the maximum operation level of the low-pressure pump 30, i.e. 10 barg. After heating the wort to the target temperature in the heating section 42 of the heat exchanger unit 40, typically around 2 to 5 degrees C higher than the incoming wort coming out of the regenerative section 41 . The wort is fed via a fluid line 14 to a holding cell 70, where it is kept pressurized. Upstream of the holding cell 70, a static mixer 60 can be provided. This creates turbulences with the flow passing through. Additionally, or alternatively, one or more static mixers can be installed in the holding cell to provide turbulence at different holding times.

[0046] The wort is thus pressurized upstream of the energy recovery section 41 and is kept pressurized in the in the holding cell 70 by means of the same feeding pump 30, which continuously pumps the wort in the process. Alternatively, an auxiliary pump may be included upstream of the holding cell 70. The holding cell 70 can comprise a vessel, coil or tube. According to a variant, the holding cell 70 may be of a type flash pasteurizer, which comprises a tube or coil structure for holding the wort during wort boiling. The advantage of the coil / tube-type of holding cell is that it is easy to clean with a clean-in-place (CIP) arrangement, and the risk of non-homogeneous treatment of the wort can be reduced. Additionally, by the holding cell configured for continuous feed of the wort, there is no need to utilize any pressurizing medium, such as an inert gas in the holding cell. There is therefore also no need to first fill the holding cell, then fill an inert gas and then empty the holding cell. Instead, the feeding pump keeps the pressure constant in the holding cell in a continuous process. Due to the short holding times, in the present system the size of the holding cell can be minimized.

[0047] For example, in a batch process, in which a batch is 10Ohl a vessel to accumulate the wort must have a volume of 10Ohl. In the present process, with a flow rate of 100 hl / hour, the size of the vessel can be much smaller to treat the same volume in one hour. Depending on the flow rates in the process, the wort is kept in the holding cell for 100 to 600 seconds (s), or 120 to 300 s, or 150 to 210 s. The holding cell volumes are adapted to the flow rates, and as a further example may be for example 20-200 liters for flow rates of 1 -4 m3 / h. However, in bigger brewing plants, the flow rates may be much higher, and the volume of the holding cell is adapted accordingly.

[0048] To minimize the energy consumption according to the present invention, the heat- treated wort 17 from the holding cell 70 is fed back to the energy recovery section 41 of the heat exchanger unit 40, on the opposite side of it, in a counter current manner, wherein the heat-treated wort is transferring the thermal energy to the incoming wort, maximizing the heat recovery process. The heat-treated wort is thus arranged to preheat the incoming wort via wort-to-wort heat exchange. In the shown example in Fig. 1 , the heat-treated wort 17 is supplied to the heat exchanger section 41 , where the wort-to-wort heat exchange occurs, preferably in a counter current way. That is, the incoming wort 12 is heat-treated with the outgoing heat-treated wort 17. The incoming wort 12 cools the outgoing heat-treated wort 17 in the heat exchanger. The outgoing cooled wort 18 downstream of the cooling step may reach a temperature of from about 50-80°C depending on the temperature of the incoming wort 12. The cooled wort 18, which may have a temperature of about 76-78°C, typically around 2 to 5 degrees C higher than the incoming wort, is supplied via a valve arrangement or routing system, for example a swing bend panel to an atmospheric tank (not shown), for example a whirlpool tank or a separator and its required surrounding equipment. In the separation step coagulated proteins are separated. After the separation of the coagulated proteins the wort can then be further cooled down if not already done to the right stripping temperature and then sent to a stripping column fed with air, CO2 or N2, where the DMS can be removed. If required, the stripped wort can then further be cooled down to a fermentation temperature, and the brewing process may continue in the known way.

[0049] Reference is now made to Fig. 2, which is similar to the system described in Fig. 1 , but wherein the system 100 is connected to a routing system 80’ connecting the heat- treated and cooled wort 18 from the heat exchanger unit 40 to different downstream operations. The downstream processes may comprise, but are not limited to, a precooler 130 used for or additional cooling of the heat-treated wort before it enters a stripping column 110. The downstream process also comprises a whirlpool or separator 120 to separate the wort and a wort cooler or cellar 140. The additional cooling can be performed by a pre-cooling unit separate from the heat exchanger unit 40 and can be placed anywhere downstream of the heat exchanger unit 40 and upstream of the stripping column. The stripping is suitably performed by means of inert gas such as air, nitrogen or carbon dioxide.

[0050] In Fig. 3 a further variant of the system 100 is shown, which is similar to the system described in Fig. 1 and 2, but wherein the heat exchanger unit 40’ is shown according to a further embodiment of the invention. In this variant, the heat exchanger unit 40’ comprises the first and second heat exchanger sections 41 and 42 as described in connection with Fig. 1 and 2 and a further cooling heat exchanger section 43 to provide additional cooling of the wort before it enters downstream processes, including stripping of the undesired compounds, such as DMS, from the wort.

[0051] In the Fig. 3 shown variant, the outgoing wort 17 enters the last section 43 of the heat exchanger unit 40’ to be potentially further cooled down to a chosen target temperature facilitating the DMS stripping process. The target cooling temperature may be for example as low as 10 degrees C, which is a wort fermentation temperature. The temperature can be higher, depending on the downstream processes, such as up to about 75 degrees C. As mentioned above, this cooling step can alternatively or additionally take place after the separation step, e.g. in a whirlpool, where the trub in the wort is separated. The present system may only use cold water as a cooling media in the last optional cooling step.

[0052] The advantage of the present system is that the large majority of the heat used for the thermal treatment of the wort can be recovered in one step via the energy recovery section 41 of the heat exchanger unit 40, 40’ where wort-to-wort heat exchange takes place. The wort-to-wort, or liquid-to-liquid, heat exchange originating from the same batch, suppresses the need of doing more than one batch to recover the energy. Since there is no need for a cooling media to transport the main heat required for the thermal treatment of the wort, there is no need for an additional heat exchanger which would take the energy from wort to the cooling media and then from the cooling media to the wort. Even if each heat exchanger had a high energy recovery rate, such as 95%, the total recovery would be only 90% due to the losses from 2 different medias and heat exchangers. Thus, thanks to the wort-to-wort heatexchange between the incoming and outgoing wort in a plate heat exchanger, a very high energy recovery rate, for example 95%, can be reached by the present invention.

[0053] The cooled wort 18, which may have a temperature of below about 76-80°C is supplied via the routing system 80’to an atmospheric tank (not shown), for example a whirlpool tank or a separator and its required surrounding equipment. After the separation of the coagulated proteins the wort can then be further cooled down and then sent to a stripping column fed with air, CO2 or N2, where the DMS can be removed. If required, the stripped wort can then further be cooled down to a fermentation temperature, and the brewing process may continue in the known way. By having the further pre-cooling step in connection with or separate from the energy recovery unit and upstream of the stripping column, ensures the right temperature from the DMS stripping while reducing the need for further cooling by for example a traditional wort cooler in the brewery process.

[0054] The above detailed description explains the invention by way of example. The scope of the invention is defined in the appended claims.

Claims

CLAIMS1 . Process for continuous wort thermal treatment in a beer brewing process, comprising the steps of:- providing incoming wort into which hops have been added at a temperature of 50 to 90°C, or 60 to 85°C, or 70 to 80°C, or between 72-78°C,- feeding the incoming wort to a heating step by means of a feeding pump,- heating the wort to a target temperature of 110-150°C, or about 125- 140°C, at a determined pressure, wherein the temperature is below a boiling point of the wort at the determined pressure,- supplying the heated wort to a holding cell and pressurizing the wort to the determined pressure in the holding cell by means of the feeding pump,- keeping the heated wort pressurized at the determined pressure and at the target temperature in the holding cell for about 100s to 600s, or 120 to 300 s, or 150s to 210 s.- supplying the heat-treated wort from the holding cell back to the heating step, in which the heat-treated wort is arranged to pre-heat the incoming wort, and the incoming wort is arranged to cool the heat-treated wort.

2. Process according to claim 1 , wherein the pre-heating of the incoming wort and the cooling of the outgoing heat-treated wort is arranged as a wort-to-wort heat exchange in the heat exchanger without using an additional heat exchange media.

3. Process according to claim 1 or 2, wherein the incoming wort is pre-heated by the heat-treated wort from the holding cell to a temperature, which is less than 10°C from a target temperature at a determined pressure.

4. Process according to claim 3, wherein the heating step comprises additionally heating the incoming wort to the target temperature at the determined pressure by using steam or super-heated water for the heating.

5. Process according to any of the preceding claims, wherein the incoming wort is arranged to cool the heat-treated wort from the holding cell to a temperature being 1 -10°C warmer than the temperature of the incoming wort.

6. Process according to any of the preceding claims, wherein the heat-treated wort is supplied to a further cooling step, in which the wort temperature is adapted to a downstream process step, such as stripping of DMS.

7. Continuous wort thermal treatment system, comprising:- a feeding pump for feeding incoming wort via a feed line,- a heat exchanger unit being fluidly connected to the feed line and arranged to heat the incoming wort,- a holding cell, into which the heated wort is fed and held pressurized for a specified time period at a determined pressure and temperature, which is below a boiling point of the wort at the determined pressure, wherein the wort is held pressurized by means of the pressure generated by the feeding pump, and wherein- the heat exchanger unit is arranged to receive the heat-treated wort from the holding cell, the heat exchanger unit arranged such that the heat-treated wort pre-heats the incoming wort to a target temperature, and the incoming wort cools the outgoing heat-treated wort.

8. The continuous wort thermal treatment system of claim 7, wherein the preheating of the incoming wort and the cooling of the outgoing heat-treated wort is arranged as a wort-to-wort heat exchange in the heat exchanger unit without using an additional heat exchange media, preferably in a counter current arrangement.

9. The continuous wort thermal treatment system of claim 7 or 8, wherein the heat exchanger is fluidly connected to a steam generator arranged to additionally heat the pre-heated wort to the target temperature at a determined pressure.

10. The continuous wort thermal treatment system of any one of claims 7-9, wherein the heat exchanger unit comprises one or more plate heat exchanger sections.11 . The continuous wort thermal treatment system of any one of claims 7 to 10, wherein the heat exchanger unit comprises a first section arranged to pre-heat the incoming wort and cool the heat-treated wort.

12. The continuous wort thermal treatment system of any one of claims 7-11 , wherein the heat exchanger comprises a second section, which is fluidly connected to the steam generator arranged to additionally heat the pre-heated wort to the target temperature at the determined pressure.

13. The continuous wort thermal treatment system of claim any one of claims 7 to 12, wherein the heat exchanger unit further comprises a third section arranged to further cool the heat-treated wort.

14. The continuous wort thermal treatment system of any one of claims 7 to 13, wherein the system further comprises a stripping column fed with air, CO2 or N2 for the removal of DMS.

15. The continuous wort thermal treatment system of any one of claims 7 to 14, wherein the system further comprises an atmospheric whirlpool tank, in which coagulated proteins are separated.

16. The continuous wort thermal treatment system of claim 15, wherein the atmospheric whirlpool tank is located upstream of the stripping column.

17. The continuous wort thermal treatment system of claim 15, wherein the atmospheric whirlpool tank is located downstream of the stripping column.

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