A process for boiling wort in a beer production process

Abstract

The application discloses a wort boiling process in beer production, comprising the following steps: S1, the wort obtained after filtration enters a boiling kettle, and the wort is boiled to 98±0.5 DEG C by using steam introduced into the upper layer and the lower layer of the boiling kettle; S2, the wort is continuously boiled by using steam, and nitrogen is blown into the boiling kettle until all the wort obtained after filtration enters the boiling kettle; S3, the steam introduced into the lower layer of the boiling kettle is stopped, the wort is heated to boiling by using the steam introduced into the upper layer, and nitrogen is blown into the boiling kettle; wherein, the total amount of steam introduced into the boiling kettle is 3000-6500 kg, the total time of steam introduction is 80-90 minutes, and the total amount of nitrogen is 35-130 kg. 3 The wort boiling process in beer production adopts nitrogen to replace part of steam, reduces the use of steam, and thus the purpose of saving steam is achieved, and the production cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of beer production technology, and in particular relates to a wort boiling process in beer production. Background Technology

[0002] Beer brewing involves eight steps. First, raw material preparation: the malt is ground and mixed with hot water. Second, the mashing process: the mixture is heated to a suitable temperature to promote enzyme activity, allowing the enzymes to break down starch into sugars, forming sweet wort. Third, filtering the mashed liquid: the mashed liquid is filtered through a sieve to remove sediment and solid particles, resulting in a clear liquid. Fourth, boiling and adding hops: the mashed liquid is boiled, and hops are added during the boiling process. Fifth, cooling and fermentation: the boiled liquid is rapidly cooled to fermentation temperature, yeast is added, and the mixture is transferred to a fermentation tank for fermentation. Sixth, maturation: the beer is stored at low temperatures to improve its taste and stability. Seventh, filtration and carbonation: filtration removes residual solid particles and suspended matter, and then carbon dioxide is injected to give the beer the appropriate carbon dioxide content. Eighth, bottling and packaging.

[0003] In beer production, boiling is a crucial step. Typically, steam is used as a heat source to boil the wort, removing substances that negatively impact beer flavor and achieving the required original wort concentration through evaporation. This boiling technique, which uses steam to heat the wort, consumes considerable energy. Furthermore, raising the wort to around 100°C affects its thermal effect, and excessive thermal effect can degrade the beer's taste and freshness.

[0004] Therefore, there is an urgent need for a boiling technology that can reduce boiling intensity, ensure freshness, and save energy. Summary of the Invention

[0005] In view of the above-mentioned deficiencies of the prior art, the present invention provides a wort boiling process in beer production, which uses nitrogen gas to replace part of the steam by blowing nitrogen gas before and during boiling. On the one hand, this can reduce the amount of steam used and save energy; on the other hand, it can also ensure the taste and freshness of the beer.

[0006] To address the aforementioned technical problems, this invention provides a wort boiling process in beer production, comprising the following steps:

[0007] S1. Pass the filtered wort into a boiling kettle and cook the wort to 98±0.5℃ using the steam passed through the upper and lower layers of the boiling kettle.

[0008] S2. Continue cooking the wort with steam and blow nitrogen into the boiling pot until all the wort obtained after filtration has entered the boiling pot.

[0009] S3. Stop introducing steam into the lower layer of the boiling pot, use the steam from the upper layer to heat the wort to a boil, and blow nitrogen into the boiling pot.

[0010] Among them, each heating 80-90m 3 For wort, the total steam consumption is 3000-6500 kg, the total steam introduction time is 80-90 minutes, and the total nitrogen consumption is 35-130 kg. The steam introduction time in step S3 should be greater than the sum of the steam introduction times in steps S1 and S2.

[0011] In a preferred embodiment, a preheating step is included before step S1: the filtered wort is passed into a preheater for preheating, and the preheated wort is passed into a boiling pot.

[0012] In a more preferred embodiment, the S3 step continuously generates secondary steam during the boiling process; the secondary steam is recovered and used for the preheating step.

[0013] In a preferred embodiment, the flow rate of the upper layer steam in both S1 and S2 is greater than the flow rate of the lower layer steam.

[0014] In a preferred embodiment, the flow rates of the upper and lower steam layers in S2 are greater than those of the upper and lower steam layers in S1, respectively.

[0015] In a preferred embodiment, the flow rates of the upper steam and the lower steam in S1 are 3300 kg / h and 2300 kg / h, respectively.

[0016] In a preferred embodiment, the flow rates of the upper steam and the lower steam in S2 are 4300 kg / h and 2500 kg / h, respectively.

[0017] In a preferred embodiment, the nitrogen flow rate in S3 is the same as that in S2.

[0018] In a preferred embodiment, the nitrogen flow rate in both S2 and S3 is 60 kg / h.

[0019] In a preferred embodiment, step S3 further includes the following steps:

[0020] S31. The first portion of steam is introduced at a first constant flow rate for a duration of T1.

[0021] S32. A second portion of steam is introduced at a second constant flow rate for a duration of T2; the second constant flow rate is greater than the first constant flow rate and T1 > T2.

[0022] In a preferred embodiment, the first constant flow rate is 1800 kg / h and the second constant flow rate is 2500 kg / h.

[0023] In a preferred embodiment, T1 is 40 minutes and T2 is 10 minutes.

[0024] The beneficial effects of this invention are:

[0025] (1) The wort boiling process in the beer production process of the present invention uses nitrogen to replace part of the steam, thereby reducing the use of steam, thus achieving the purpose of saving steam and reducing production costs.

[0026] (2) The wort boiling process in the beer production process of the present invention can ensure that there is no significant difference in the freshness and taste of the beer, and overcome the impact of excessive heat effect on the taste and freshness of the beer.

[0027] (3) The wort boiling process in the beer production process of the present invention can avoid the occurrence of overflow by controlling the amount of steam and nitrogen used, and facilitate the smooth progress of the boiling process. Attached Figure Description

[0028] Figure 1 These are the turbidity test results for the experimental group;

[0029] Figure 2 This is the turbidity test result for the control group.

[0030] The following will further explain the concept, specific structure, and technical effects of the present invention in conjunction with the accompanying drawings, so as to fully understand the purpose, features, and effects of the present invention. Detailed Implementation

[0031] To make the technical means, inventive features, objectives, and effects of the invention readily understandable, the invention is further illustrated below with reference to specific figures. However, the invention is not limited to the embodiments described below.

[0032] It should be noted that the structures, proportions, sizes, etc., illustrated in the accompanying drawings of this specification are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0033] The wort boiling process generally involves two main steps. First, the wort extracted from the filter or trough is heated to its boiling point. Second, the wort is kept boiling while steam is continuously introduced for heating. The heat consumed in the first step is directly proportional to the temperature rise, while the heat consumed in the second step is directly proportional to evaporation. To reduce heat consumption in the boiling kettle, brewers have tried various methods, the most obvious being reducing evaporation. Typically, the evaporation rate in the boiling kettle is 12%. Breweries can achieve evaporation rates of 4-5% through repeated process optimization, but the heat consumption during boiling remains significant.

[0034] The inventors of this application attempted to reduce the use of steam by blowing nitrogen to replace part of the steam. However, when blowing nitrogen, due to the low temperature and fast flow rate of nitrogen, a serious overflow problem occurs during the boiling process. This causes the boiling wort to enter the boiling pot chimney through foam and turbulence, and at the same time touch the high liquid level sensor in the pot, causing a temporary interruption of steam supply and affecting the normal production of beer.

[0035] To avoid the problem of overflowing, the inventors of this application repeatedly explored various aspects, including the amount of steam and nitrogen used, the steam introduction time, and the distinction between upper and lower steam layers, to obtain a wort boiling process that does not cause overflowing. The specific steps of this wort boiling process are as follows:

[0036] S1. Pass the filtered wort into a boiling kettle and cook the wort to 98±0.5℃ using the steam passed through the upper and lower layers of the boiling kettle.

[0037] After the saccharification process is complete, the saccharification liquid contains a large amount of solids, which need to be filtered through a filter or filter screen to obtain clear wort liquid. The filtered wort is then directly fed into a boiling kettle, where steam introduced from the upper and lower layers of the kettle is used to cook the wort, bringing the wort temperature to 98±0.5℃.

[0038] S2. Continue cooking the wort with steam and blow nitrogen into the boiling pot until all the wort obtained after filtration has entered the boiling pot.

[0039] During the cooking of wort in the boiling kettle, filtration continues, and the filtered wort is continuously fed into the boiling kettle. When the wort temperature in the boiling kettle reaches 98±0.5℃, in addition to cooking the wort with steam, nitrogen is also blown into the boiling kettle to reduce the use of some steam. This process ends when filtration is completed.

[0040] S3. Stop introducing steam into the lower layer of the boiling pot, use the steam from the upper layer to heat the wort to a boil, and blow nitrogen into the boiling pot.

[0041] Among them, each heating 80-90m 3For wort, the total steam consumption is 3000-6500 kg, the total steam introduction time is 80-90 minutes, and the total nitrogen consumption is 35-130 kg. The steam introduction time in step S3 should be greater than the sum of the steam introduction times in steps S1 and S2.

[0042] In existing steam boiling processes, the total steam consumption is about 12,000 kg. The boiling process of this invention reduces the use of steam and lowers energy consumption by blowing nitrogen gas before and during boiling.

[0043] To further reduce heat consumption, the secondary steam generated in step S3 can be recovered and used for the preheating process before step S1, which can greatly save energy and reduce costs.

[0044] In a preferred embodiment, the flow rate of the upper layer steam in both S1 and S2 is greater than the flow rate of the lower layer steam.

[0045] By setting the flow rate of the upper layer steam in S1 and S2 to be greater than that of the lower layer steam, the amount of upper layer steam used is greater than that of lower layer steam used in the same amount of time. The steam has a suppressive effect on the generation of foam, and under this condition, the occurrence of overflow foam can be suppressed.

[0046] In a preferred embodiment, the flow rates of the upper and lower steam layers in S2 are greater than those of the upper and lower steam layers in S1, respectively.

[0047] In step S2, some nitrogen is introduced along with steam. The addition of nitrogen makes overflow more likely to occur. Therefore, the steam flow rate and amount are adjusted. Compared to step S1, the amount of steam used in step S2 is relatively increased to avoid overflow problems.

[0048] In a more preferred embodiment, the flow rates of the upper steam and the lower steam in S1 are 3300 kg / h and 2300 kg / h, respectively.

[0049] In a more preferred embodiment, the flow rates of the upper steam and the lower steam in S2 are 4300 kg / h and 2500 kg / h, respectively.

[0050] In a preferred embodiment, the nitrogen flow rate in S3 is the same as that in S2.

[0051] In a preferred embodiment, the nitrogen flow rate in both S2 and S3 is 60 kg / h.

[0052] In a preferred embodiment, step S3 further includes the following steps:

[0053] S31. The first portion of steam is introduced at a first constant flow rate for a duration of T1.

[0054] S32. At a second constant flow rate for a duration of T2, a second portion of steam is introduced; the second constant flow rate is greater than the first constant flow rate, and T1 > T2.

[0055] In a preferred embodiment, the first constant flow rate is 1800 kg / h and the second constant flow rate is 2500 kg / h.

[0056] In a preferred embodiment, T1 is 40 minutes and T2 is 10 minutes.

[0057] Example

[0058] A wort boiling process in beer production includes the following steps:

[0059] S1. The filtered wort is fed into a boiling kettle and cooked to 98±0.5℃ using steam introduced from the upper and lower layers of the boiling kettle. The steam flow rate of the upper layer is 3300kg / h, the steam flow rate of the lower layer is 2300kg / h, and the steam is introduced for 15 minutes.

[0060] S2. Continue cooking the wort with steam and blow nitrogen into the boiling pot until all the wort obtained after filtration enters the boiling pot. The flow rate of the upper steam is 4300 kg / h, the flow rate of the lower steam is 2500 kg / h, the flow rate of nitrogen is 60 kg / h, and the time for introducing steam and nitrogen is 25 minutes.

[0061] S3. Stop introducing steam into the lower layer of the boiling kettle, use the steam from the upper layer to heat the wort to a boil, and blow nitrogen into the boiling kettle. S3 specifically includes the following steps:

[0062] S31. The first part of steam is introduced at a first constant flow rate of 1800 kg / h for 40 minutes;

[0063] S32. The second part of steam is introduced at a second constant flow rate of 2500 kg / h for 10 minutes.

[0064] The nitrogen flow rate remains at 60 kg / h. Specific process parameters are summarized in Table 1.

[0065] Table 1

[0066]

[0067] Under the above process conditions, the occurrence of overflow can be completely avoided.

[0068] Comparative Example 1

[0069] A wort boiling process in beer production includes the following steps:

[0070] S1. The filtered wort is fed into a boiling kettle and cooked to 98±0.5℃ using steam introduced from the upper and lower layers of the boiling kettle. The steam flow rate of the upper layer is 3300kg / h, the steam flow rate of the lower layer is 2300kg / h, and the steam is introduced for 15 minutes.

[0071] S2. Continue cooking the wort with steam and blow nitrogen into the boiling pot until all the wort obtained after filtration enters the boiling pot. The flow rate of the upper steam is 4300 kg / h, the flow rate of the lower steam is 3000 kg / h, the flow rate of nitrogen is 75 kg / h, and the time for introducing steam and nitrogen is 25 minutes.

[0072] S3. Heat the wort to a boil using the upper and lower steam layers, and purge nitrogen gas into the boiling pot. S3 specifically includes the following steps:

[0073] S31. Introduce upper layer steam at a flow rate of 1800 kg / h, introduce lower layer steam at a flow rate of 500 kg / h, and purge nitrogen at a flow rate of 120 kg / h for 40 minutes.

[0074] S32. Introduce upper layer steam at a flow rate of 3400 kg / h, introduce lower layer steam at a flow rate of 2000 kg / h, and purge nitrogen at a flow rate of 75 kg / h for 10 minutes.

[0075] The specific process parameters are summarized in Table 2:

[0076] Table 2

[0077]

[0078] Under the process conditions of Comparative Example 1, nitrogen gas was introduced at the beginning of step S2. Due to the high flow rate of nitrogen gas and the introduction of steam in both the upper and lower layers of steps S31 and S32, a relatively serious overflow phenomenon occurred in steps S31 and S32.

[0079] Comparative Example 2

[0080] A wort boiling process in beer production includes the following steps:

[0081] S1. The filtered wort is fed into a boiling kettle and cooked to 98±0.5℃ using steam introduced from the upper and lower layers of the boiling kettle. The steam flow rate of the upper layer is 3000 kg / h, the steam flow rate of the lower layer is 2000 kg / h, and the steam is introduced for 15 minutes.

[0082] S2. Continue cooking the wort with steam and blow nitrogen into the boiling pot until all the wort obtained after filtration enters the boiling pot. The flow rate of the upper steam is 4300 kg / h, the flow rate of the lower steam is 3000 kg / h, the flow rate of nitrogen is 75 kg / h, and the time for introducing steam and nitrogen is 25 minutes.

[0083] S3. Heat the wort to a boil using the upper and lower steam layers, and purge nitrogen gas into the boiling pot. S3 includes the following steps:

[0084] S31. Introduce upper layer steam at a flow rate of 1500 kg / h, introduce lower layer steam at a flow rate of 500 kg / h, and purge nitrogen at a flow rate of 60 kg / h for 40 minutes.

[0085] S32. Introduce upper layer steam at a flow rate of 3400 kg / h, introduce lower layer steam at a flow rate of 2000 kg / h, and purge nitrogen at a flow rate of 60 kg / h for 10 minutes.

[0086] The specific process parameters are summarized in Table 3:

[0087] Table 3

[0088]

[0089]

[0090] Comparative Example 2, based on Comparative Example 1, adjusted the steam flow rate, reducing the upper layer flow rate from 3300 kg / h and the lower layer flow rate from 2300 kg / h to 3000 kg / h and 2000 kg / h respectively in step S1. Furthermore, the nitrogen flow rate in step S31 was reduced from 120 kg / h to 60 kg / h. Bubbling began to occur 5 minutes after nitrogen was introduced. Therefore, simply reducing the nitrogen flow rate cannot solve the bubble overflow problem.

[0091] Comparative Example 3

[0092] A wort boiling process in beer production includes the following steps:

[0093] S1. The filtered wort is fed into a boiling kettle and cooked to 98±0.5℃ using steam introduced from the upper and lower layers of the boiling kettle. The steam flow rate of the upper layer is 3300kg / h, the steam flow rate of the lower layer is 2300kg / h, and the steam is introduced for 15 minutes.

[0094] S2. Continue cooking the wort with steam and blow nitrogen into the boiling pot until all the wort obtained after filtration enters the boiling pot. The flow rate of the upper steam is 4300 kg / h, the flow rate of the lower steam is 2500 kg / h, the flow rate of nitrogen is 60 kg / h, and the time for introducing steam and nitrogen is 25 minutes.

[0095] S3. Heat the wort to a boil using the upper and lower steam layers, and purge nitrogen gas into the boiling pot. S3 includes the following steps:

[0096] S31. Introduce steam into the upper layer at a flow rate of 1500 kg / h, stop introducing steam into the lower layer, and purge nitrogen at a flow rate of 60 kg / h for 40 minutes.

[0097] S32. Introduce upper layer steam at a flow rate of 3400 kg / h, introduce lower layer steam at a flow rate of 2000 kg / h, and purge nitrogen at a flow rate of 60 kg / h for 10 minutes.

[0098] The specific process parameters are summarized in Table 4:

[0099] Table 4

[0100]

[0101] In Comparative Example 3, the flow rate of nitrogen was reduced, and the lower layer steam was stopped in step S31 while the lower layer steam was continued in step S32. This achieved the effect of preventing overflow for a certain period of time, but it could not guarantee that no overflow would occur throughout the entire process.

[0102] In summary, in the wort boiling process, in addition to requiring the total nitrogen and total steam consumption to be within a certain range, whether steam is introduced into the lower layer of the boiling pot in step S3 is also a key factor. Only when both conditions are met can the problem of overflow be successfully solved.

[0103] Freshness and Turbidity Measurement

[0104] To investigate whether the addition of nitrogen during wort boiling affects the freshness and turbidity of beer, the freshness and turbidity of beer in the experimental and control groups were measured.

[0105] Freshness, as an indicator of the stability of beer's flavor under different storage conditions during its shelf life, can be evaluated through some test data.

[0106] The Stability Index (SI) is a comprehensive indicator that unifies the oxidative driving force and antioxidant capacity during the aging process. Beer aging is actually a combined result of decreasing antioxidants and increasing typical flavor aging compounds. Therefore, beer flavor stability requires two things: 1. low levels of aging or aging precursor substances; 2. high levels of antioxidants.

[0107] SI = DPPH removal amount / TBA value

[0108] DPPH scavenging capacity serves as an indicator of antioxidant capacity to scavenge free radicals; TBA value refers to the total amount of carbonyl compounds in aged beer, comprehensively reflecting the aging status of the beer. A higher DPPH scavenging value indicates stronger endogenous antioxidant capacity and less aging; conversely, a higher TBA value indicates more carbonyl compounds and more severe aging. Fresher beers have higher SI values; as aging progresses, the SI value decreases.

[0109] The difference between the experimental group and the control group is that the experimental group used the boiling process described in the example, while the control group used a steam-heated boiling process.

[0110] The SI, DPPH, and TBA values ​​of the beer produced in the experimental group and the control group were tested respectively.

[0111] The method for testing TBA values ​​is as follows:

[0112] (1) Take 10 mL of wine sample and centrifuge at 10000 rpm for 10 min until clear.

[0113] (2) Take 5 mL of the supernatant and mix it thoroughly with 2 mL of 0.33% TBA in 50% acetic acid solution. Heat the mixture precisely in a 60℃ water bath for 60 min, then cool it rapidly. Measure the absorbance at 530 nm, using distilled water as a blank and zeroing the sample. The TBA value represents the content of aging substances in the sample; the higher the TBA value, the more aging substances are present in the sample.

[0114] The DPPH value is tested as follows:

[0115] DPPH (1,1-Diphenyl-2-picrylhydrazyl radical) is a 1,1-diphenyl-2-picrylhydrazyl radical. It is widely used for the quantitative determination of the antioxidant capacity of biological samples and food. After degassing the beer sample by shaking, dilute it 10 times with distilled water. For testing, place 2 mL of the 10-fold diluted sample and 3 mL of DPPH working solution in a stoppered test tube, mix quickly, and incubate in a 25°C water bath for 30 min. Measure the absorbance at 517 nm using 80% methanol as a blank.

[0116] DPPH removal rate = [1 - (Ai - Aj) / Ac] × 100%

[0117] Ac = 2 mL 80% methanol + 3 mL DPPH working solution absorbance

[0118] Ai = 3 mL DPPH working solution + 1.8 mL distilled water + 0.2 mL absorbance of the sample to be tested

[0119] Aj = 3 mL 80% methanol + 1.8 mL distilled water + 0.2 mL absorbance of the sample to be tested

[0120] DPPH scavenging rate represents a sample's ability to scavenge free radicals, i.e., its reducing power. The higher the DPPH scavenging rate, the stronger the reducing power of the sample.

[0121] The test results are shown in Table 5. Among them, 16#21-16#24 are the experimental group, and 20#25-20#28 are the control group.

[0122] Table 5

[0123]

[0124] As can be seen from Table 5, the mean SI value of the experimental group was 33.88, while the mean SI value of the control group was 30.87. The difference between the two was not significant, and their freshness was similar.

[0125] In addition, the beer produced by the experimental group and the control group was fortified, and the fortification turbidity was measured respectively.

[0126] Specific procedure: Beers produced in the experimental and control groups were stored at a constant temperature of 32℃ for 14 days. Samples were taken, and the turbidity of each group was measured twice using a beer turbidimeter. The results for the experimental group are as follows: Figure 1 As shown, the results of the control group are as follows: Figure 2 As shown.

[0127] By comparison Figure 1 and Figure 2 It can be seen that there is no significant difference in turbidity between the two.

[0128] In summary, the boiling process of this invention reduces the amount of steam used while ensuring the freshness and turbidity of the beer.

[0129] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A wort boiling process in a beer production process, characterized in that, The method comprises the following steps: S1, passing the wort obtained after filtration into a boiling kettle, and using the steam passed into the upper layer and the lower layer of the boiling kettle to cook the wort to 98±0.5℃; S2, continuing to cook the wort using steam, and blowing nitrogen into the boiling kettle until all the wort obtained after filtration is passed into the boiling kettle to end, wherein the flow rate of the upper layer steam in S1 and S2 is greater than that of the lower layer steam; S3, stopping the steam from being passed into the lower layer of the boiling kettle, heating the wort using the upper layer steam to boiling, and blowing nitrogen into the boiling kettle; The S3 step further comprises the following steps S31, passing a first part of steam at a first constant flow rate for T1; S32, passing a second part of steam at a second constant flow rate for T2, wherein the second constant flow rate is greater than the first constant flow rate and T1>T2; wherein the amount of steam per 80-90 m 3 wort, the total amount of steam is 3000-6500 kg, the total time of steam injection is 80-90 minutes, the flow rate of nitrogen in S2 and S3 is 60 kg / h, the total amount of nitrogen is 35-130 kg, and the time of steam injection in S3 is greater than the sum of the times of steam injection in S1 and S2.

2. Wort boiling process in beer production according to claim 1, characterized in that, The S1 step further comprises a preheating step: passing the wort obtained after filtration into a preheater for preheating, and passing the preheated wort into the boiling kettle.

3. Wort boiling process in beer production according to claim 2, characterized in that, The S3 step continuously generates secondary steam during the boiling process; the secondary steam is recovered and used in the preheating step.

4. Wort boiling process in beer production according to any of claims 1 to 3, characterized in that, The flow rates of the upper layer steam and the lower layer steam in S2 are greater than those in S1.

5. A wort boiling process in a beer production process as claimed in claim 1, characterized in that, The first constant flow rate is 1800 kg / h, and the second constant flow rate is 2500 kg / h.

6. A wort boiling process in a beer production process as claimed in claim 1, characterized in that, T1 is 40 minutes, and T2 is 10 minutes.

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