JP3183616B2 - Beer filtration method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for filtering a fermented beer fermentation liquor, that is, a technique for producing a clear product beer by removing insoluble substances such as yeasts and proteins in a beer fermentation end liquid aged after post-fermentation. It is about.

[0002]

2. Description of the Related Art Generally, a filtration method using diatomaceous earth as a filter aid has been used for filtering a fermented beer liquid. This method is a method in which a filtration layer is formed by diatomaceous earth, and insolubles are filtered through gaps generated thereby.

However, in this method, diatomaceous earth as a filter aid cannot be reused and is discarded.
There is a problem in terms of effective use of resources, and also a problem in that the cost of treating used diatomaceous earth is large.

In order to deal with such a problem, Japanese Patent Application Laid-Open Nos. 62-3782 and 62-213817 disclose the method.
Japanese Patent Application Laid-Open Publication No. HEI 9-214969 proposes a so-called cross-flow filtration method using a porous filter. However, cross-flow filtration has the disadvantage that the membrane permeation flux is much smaller than that of filtration using a filter aid such as diatomaceous earth, and beer filtration intended to process a large amount of fermentation liquor. There was a practical problem in the process. Further, in this method, there still remain basic technical problems such as difficulty in controlling for constant-rate filtration and clogging caused by precipitation caused by circulating beer.

Recently, a filtration method has been proposed in which backwashing is periodically performed using a special microfiltration membrane (for example, Japanese Patent Application Laid-Open No. 4-317723). This method
It is characterized by using a microfiltration membrane having anisotropic pore diameter in the thickness direction. And it is said that clogging is remarkably improved by using this membrane, and furthermore, filtration can be achieved practically even with a completely unfiltered beer fermentation finished liquid by periodic backwashing. It is a very excellent technology that can solve the problems of the conventional filtration technology.
However, the present inventors conducted an experiment of filtering the actual beer fermentation finished liquid, and found that although the total amount of filtration until clogging was sufficiently obtained in the state of a new membrane, the used membrane was washed. When a regenerated membrane is used, the total amount of filtration becomes very small, and it has been clarified that the filtration process cannot be carried out to justify the cost with this technique.

[0006] In order to prevent clogging in the periodic backwashing filtration technique, a method of adding a protease or a cellulolytic enzyme to a backwash solution has also been proposed (Japanese Patent Application Laid-Open No. 4-267933). However, when the beer fermentation finished liquid is subjected to filtration, the effect of preventing clogging of the washed and regenerated membrane has not been so expected.

[0007] On the other hand, in the conventional method of filtering a beer fermentation end liquid using diatomaceous earth as a filter aid, there is often a problem of difficulty in filtering, and many measures have been considered. For example, a method of adsorbing a substance that deteriorates filterability with silica gel, silica sol, PVPP (polyvinylpolypyrrolidone), or the like has been known for a long time, and a part of the method has been put to practical use. In addition, a method of adding silica sol during post-fermentation and centrifuging the silica sol is proposed in DE-A-3231240. There is also known a method of improving the filterability of a filter aid by subjecting wort as a beer raw material to an enzyme treatment with β-glucanase or xylanase (for example, Japanese Patent Publication No. 6-99784).

[0008] However, these have been to prevent primary clogging in conventional diatomaceous earth filtration.

Therefore, the present invention provides a filtration method in which backwashing is periodically performed using a microfiltration membrane, which also prevents clogging of a regenerated membrane obtained by washing a membrane used for filtering a beer fermentation end solution. The method was not known at all.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method using a microfiltration membrane having an anisotropic pore diameter in the thickness direction of the membrane. In the backwashing technology, we developed a technology to improve the amount of filtration by preventing clogging of the regenerated membrane when washing and reusing the membrane used for filtration of the beer fermentation finished liquid, and It is to provide a filtration technique.

[0011]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to improve the method of performing filtration with periodic backwashing using a microfiltration membrane. The present inventors have found that by using a beer fermentation termination liquid produced using wort obtained by performing a glucanase treatment, it is possible to obtain a sufficient total filtration amount without clogging even when a regenerated membrane is used. Was completed.

That is, the present invention relates to a method for beer filtration which uses a microfiltration membrane having an anisotropic pore diameter in the thickness direction of the membrane and filters the undiluted solution with periodic backwashing. Is a beer fermentation end liquid produced using wort obtained by performing β-glucanase treatment in a preparation step for wort production.

As a more preferred embodiment, the microfiltration membrane having an anisotropic pore diameter in the thickness direction of the membrane has a pore diameter of 4 to 30 μm on the inlet side surface where the undiluted solution first comes into contact with the membrane, and the densest membrane of the membrane. Is configured to have a pore diameter of 0.8 to 4.0 μm.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a specific configuration of the beer filtration method of the present invention will be described in detail.

The first characteristic feature of the present invention is that even when a regenerated membrane obtained by regenerating a microfiltration membrane is used, a liquid to be filtered is obtained so that a sufficient total filtration amount can be obtained without clogging immediately. In the course of producing the beer fermentation finished liquid, which is a process for preparing wort.

That is, in the present invention, in the preparation step for wort production, β-glucanase is introduced into β-glucanase.
Glucanase treatment (enzyme treatment) is performed. The charging step for wort production refers to a step of mixing the crushed malt (and the starchy auxiliary material) with warm water and converting it into low-molecular-weight mash (mesh) by the enzyme of the malt itself. As the β-glucanase used in this preparation step, any of those capable of hydrolyzing β-glucan, such as those derived from Aspergillus, those derived from Bacillus, and those derived from penicillium, can be used.
Β-glucanase derived from insolens is most preferred in that it has a wide optimum temperature range.

The amount of enzyme to be added is 100 kg of malt to be used.
250-5000 FBU (Fungal Beta Glucanase
unit) may be used, and a preferable addition amount is 500 to 10
00FBU. The enzyme may be added at any time during the charging period, but in order to perform the enzyme reaction sufficiently, it is preferable to add the crushed malt simultaneously with the warm water in the saccharification tank. The charging temperature may be initially maintained at about 45 to 55 ° C as usual, and then increased to about 60 to 70 ° C by adding auxiliary materials such as rice and starch.

The wort is produced from the mash thus produced, and the main fermentation and the post-fermentation are carried out in the same manner as in normal beer production to produce a finished liquid of beer fermentation.

The beer fermentation finished liquid thus obtained is then subjected to a filtration method involving periodic backwashing using a microfiltration membrane having an anisotropic pore diameter in the thickness direction of the membrane.

The term “filtration method involving periodic backwashing” as used herein means that when filtering a stock solution using a microfiltration membrane, pressure is applied from the permeate side of the filtration membrane every certain time and the filtrate is filtered from the permeate side. Filtration is performed while intermittently removing clogging substances by flowing a fluid to the fluid side (in the opposite direction).

The microfiltration membrane having anisotropy in the pore diameter in the thickness direction of the membrane as used herein refers to a membrane whose pore diameter continuously changes from one side of the membrane to the opposite direction, or the inside of the membrane. And those having a minimum pore diameter outside the membrane (the densest layer).

Typical film materials (polymers) for forming a film having an anisotropic structure include cellulose acetate and polysulfone, and polyvinyl chloride and polyvinylidene fluoride also form an anisotropic structure. The production of the microfiltration membrane having such an anisotropic structure, the above-mentioned polymer was mixed with a good solvent, or a mixed solvent of a good solvent and a non-solvent, or a plurality of solvents having different degrees of solubility in the polymer. To prepare a membrane-forming stock solution,
This is carried out by casting on a support or directly in a coagulating liquid, washing and drying.

In this case, preferred examples of the solvent (good solvent) for dissolving the polymer include dichloromethane,
Examples include acetone, dimethylformamide, dimethylacetamide, dimethylsulfoxide, 2-pyrrolidone, N-methyl-2-pyrrolidone, and sulfolane.

Specific examples of non-solvents which can be added to such a solvent include cellosolves; alcohols such as methanol, ethanol and isopropanol; ketones such as acetone and methyl ethyl ketone; tetrahydrofuran;
Ethers such as dioxane; polyethylene glycol;
Examples include polyols such as glycerin and ethyl glycol. The ratio of the non-solvent to the good solvent may be in any range as long as the mixture can maintain a uniform state, but is particularly preferably in the range of 5 to 50 parts by weight.

In order to control the porous structure of the membrane,
An inorganic electrolyte, an organic electrolyte, a polymer electrolyte, or the like, which is called a swelling agent, can be added. Examples of usable electrolytes include metal salts of inorganic acids such as sodium chloride, sodium nitrate, potassium nitrate, sodium sulfate, zinc chloride and magnesium bromide; organic acid salts such as sodium acetate, sodium formate and potassium butyrate; sodium polystyrene sulfonate and polyvinyl Polymer electrolytes such as pyrrolidone and polyvinylbenzyltrimethylammonium chloride; and ionic surfactants such as sodium dioctylsulfosuccinate and sodium alkylmethyltaurate.

Although some of these electrolytes show a certain effect even when added alone to a polymer solution, particularly remarkable effects may be obtained when these electrolytes are added as an aqueous solution. The amount of the aqueous electrolyte solution is not particularly limited as long as the uniformity of the solution is not lost by the addition, but is usually from 0.5 parts by weight to 10% by volume based on the solvent. The concentration of the aqueous electrolyte solution is not particularly limited, and the higher the concentration, the greater the effect. However, a commonly used concentration is 1 to 60 parts by weight.

The concentration of the polymer as a stock solution is 5 to 5.
It is 35% by weight, preferably 10 to 30% by weight. If this value exceeds 35% by weight, the water permeability of the resulting microporous membrane will be too small to have any practical significance. On the other hand, if this value is less than 5% by weight, there arises a disadvantage that a microfiltration membrane having a sufficient separation ability cannot be obtained.

The membrane-forming stock solution prepared as described above is cast on a support, and the polymer solution membrane together with the support is immersed in the coagulation solution immediately after casting or after a certain period of time. Water is generally used as the coagulating liquid, but an organic solvent that does not dissolve the polymer may be used. Two or more organic solvents may be used as a mixture. As the support, generally, any material having a function as a support when producing a microfiltration membrane can be used. In particular, when a non-woven fabric is used, it is not necessary to peel off the support, which is preferable. Examples of the nonwoven fabric that can be used include general nonwoven fabrics made of polypropylene, polyester, and the like.

The cast film in which the polymer is precipitated in the bath of the coagulating liquid is dried after washing with water, washing with warm water, washing with a solvent and the like.

The microfiltration membrane thus produced having anisotropic pore diameter in the thickness direction has a pore diameter at the inlet side surface where the undiluted filtrate first comes into contact with the membrane in order to realize effective filtration of beer. The pore diameter of the densest layer (the layer in which the smallest pore diameter is distributed) present in the membrane or on the outlet side is preferably 0.8 to 4.0 µm. Further, from the viewpoint of sterilization, the pore diameter of the densest layer is about 0.8 to 1.2 μm, and the pore diameter on the inlet side is 24 to 24 to capture a suspended substance such as yeast and obtain a large total filtration amount. Most preferably, about 30 μm.

If the filtration flux is low, it is possible to prevent an increase in the filtration differential pressure and to extend the filtration time. However, in order to perform efficient filtration commensurate with the membrane cost, 100 L / m ² is required.
-The h position is appropriate.

As an index of clogging, a filtration pressure difference value is used. The filtration differential pressure is the difference between the pressure on the raw fluid side and the pressure on the permeate side, and if it is 0.2 to 0.3 kg / cm ² or less, a sufficient filtration flux can be obtained, but it exceeds that Then, the membrane needs to be washed, and filtration is performed again by the washed and regenerated membrane.

For the regeneration of the filtration membrane, any generally used cleaning method can be used, but since it is used in a beer factory, it is necessary to have high safety and a high cleaning effect. From that point, for example, first, 2
A solution obtained by adding 100 ppm of hypochlorous acid to an aqueous solution of sodium hydroxide at 50 ° C. for 1 hour at 400 L / m ² · h, and then washing the solution obtained by adding 2% hydrogen peroxide to a 2% aqueous solution of nitric acid in 60% ℃ 1 hour 400L / m ² · h
And finally washing with water, or a method of mixing 2% β-glucanase and 2% protease, immersing for 2 hours, and washing with hot water and water.

The microfiltration membrane produced above is usually assembled into a known module such as a pleated cartridge, a flat membrane laminated structure cartridge and the like and subjected to filtration.

In the present invention, filtration is performed with periodic backwashing. However, the backwashing cycle and backwashing time are not particularly limited, and optimum productivity is taken into consideration. What is necessary is just to set appropriately.

FIG. 7 shows a schematic process diagram for filtering with periodic backwashing. In this figure,
The undiluted filtrate 4 is sent to the filter housing 1 by the pump 2, and the filtered filtrate is sent to the filtrate storage tank 5. When the filtration pressure is gradually increased for a certain period of time, the pump 2 is stopped, the gas is introduced from the gas supply port 7 to the primary side of the filter, and the remaining liquid is pushed out to the secondary side. Next, the backwashing liquid 6 is
Is sent to the filter housing 1 and pushes out the particle cake captured at the backwash liquid outlet. This time, gas is introduced from the secondary side of the filter, the remaining backwash liquid is pushed out to the outlet, and then filtration is restarted by the pump 2 again.

The removal of the backwash liquid remaining in the housing 1 may be omitted if there is a further purification step using an antibiotic or an amino acid. Water is usually used as the backwash liquid, but a filtrate can also be used.

[0038]

The present invention will be described below in more detail with reference to specific examples.

Example 1 350 kg of malt was pulverized into 5
Put into hot water of 0 ° C and further add 70 mL of β-glucanase (“Ultraflow” (50 FBU / mL) manufactured by Novo).
Was added. After leaving it at 50 ° C. for 1 hour, 45 kg of rice as an auxiliary material, 35 kg of corn grits and 20 kg of corn starch were added in advance in a rice boiling kettle, and the temperature was raised from 45 ° C. to 70 ° C. Over time, the moromi was completed.

Using this moromi, wort filtration, wort boiling and hop addition were carried out in the usual manner to prepare 2000 L of raw wort. Main beer fermentation and post-fermentation were carried out by adding bottom beer yeast to this.

Next, a pleated cartridge type polysulfone anisotropic microfiltration membrane manufactured by Fuji Photo Film Co., Ltd. (inlet pore diameter: about 27 μm, pore diameter: 0.87 μm, membrane area: 0.4
5 m ² , film thickness of 180 to 240 μm), and the obtained fermentation ending solution was filtered at a filtration flux of 100 L / m ² at the start of filtration.
-The time was set, and filtration was performed for 20 hours while performing backwashing for 30 seconds every 30 minutes. The change in filtration flux is shown in the graph of FIG. From these results, it was found that a filtration flux of 100 L / m ² · hour was obtained up to 20 hours under the constant voltage of the pump.

The obtained product beer was excellent in flavor and was inferior to ordinary beer.

[Embodiment 2] In the same manner as in Embodiment 1, 10
A solution obtained by adding 100 ppm of hypochlorous acid to a 2% aqueous sodium hydroxide solution at 50 ° C.
After washing for 2 hours, a solution obtained by adding 2% hydrogen peroxide to a 2% aqueous solution of nitric acid was washed at 60 ° C. for 1 hour, and finally washed with water for regeneration.

Using the regenerated membrane, the same fermentation-finished solution as in Example 1 was filtered under the same conditions as in Example 1. As a result, the filtration flux could be maintained at 100 L / m ² · hour for up to 10 hours from the start again.

Further, in exactly the same manner, an experiment was conducted by alternately repeating the regeneration and filtration of the membrane by washing seven times. All of the regenerated membranes were able to sufficiently maintain the filtration flux. Further, as shown in FIG. 2, the increase in the filtration pressure difference was slight, and almost no increase in the filtration pressure difference was observed after the third washing.

The total filtration amount by one filtration is 1 m in membrane area.
If it is 1000L or more per ^2, it is considered to be a technology that can be used practically at the beer factory site, and according to this method, the amount of the regenerated membrane can be obtained in 10 hours from the start,
It was determined that the technology was sufficiently practical.

[Comparative Example 1] A beer fermentation finished solution produced in exactly the same manner as described in Example 1 except that β-glucanase was not added was used as a stock solution for filtration.

The filtration conditions including the properties of the membrane used and the washing conditions were the same as those in Examples 1 and 2 above.
The experiment was conducted by alternately repeating the regeneration and filtration of the membrane by washing five times.

FIG. 3 and FIG. 4 show the change over time of the filtration flux when a new membrane is used and the change over time of the filtration pressure difference when a regenerated membrane is used.

As shown in FIG. 3, even when a new membrane was used, the filtration flux began to drop from about 7 hours after the start, and only 14 L / m ² · hour was obtained about 18 hours from the start of the filtration. Was.

Further, as shown in FIG. 4, when the regenerated membrane was used, clogging became more remarkable, and the filtration differential pressure started to rise immediately after the start. It was found that the filtration flux could not maintain a predetermined 100 L / m ² · hour after 4 hours with the membrane regenerated twice and 3 hours after the third regeneration.

Therefore, when a regenerated membrane is used, the total filtration amount per 1 m ^{2 of} the membrane area is at most 300 L, which is not practical.

Comparative Example 2 A beer main fermentation liquor produced in exactly the same manner as described in Example 1 except that β-glucanase was not added was mixed with 150 μl of silica sol.
After pm was added and fermentation was performed, continuous centrifugation was performed at about 3000 g, and the separated liquid was used as a filtrate.

The filtration conditions and washing conditions including the properties of the membrane used were the same as those in Examples 1 and 2 above.
The experiment was conducted by alternately repeating regeneration-filtration of the membrane by purification six times.

FIG. 5 and FIG. 6 show the change over time of the filtration flux when a new membrane is used and the change over time of the filtration differential pressure when a regenerated membrane is used.

As shown in FIG. 5, a certain degree of clogging prevention effect was confirmed. For a new membrane, a predetermined filtration flux of 100 L / m ² · hour could be maintained for 12 hours from the start.

However, as shown in FIG. 6, when the regenerated membrane was used, it was confirmed that the filtration differential pressure started to increase immediately after the filtration was started. The rate of increase in the differential pressure gradually increases with the number of times of regeneration, and for a film regenerated three times, for 8 hours,
In the case of the membrane regenerated four times, a rapid rise in the differential pressure is expected in the case of constant-speed filtration after 5 hours, and the filtration flux becomes a predetermined 100 L / m.
^{2. It} became clear that time could not be maintained. Thus, membrane area 1 m ² per 500 a film reproduced four times or more
Only L can be filtered.

From the above results, as for the combination of silica sol and centrifugal separation, which are effective as a measure for preventing clogging during filtration using a filter aid, the membrane was not used in the periodic backwash filtration using a microfiltration membrane. It was found that there was almost no effect of preventing clogging when used after washing and recycling.

[0059]

The effects of the present invention are apparent from the results of the above embodiments. That is, in the present invention, the beer fermentation end liquid produced using wort obtained by performing the β-glucanase treatment in the charging step is configured to be filtered with a periodic backwash using a microfiltration membrane. Therefore, a sufficient total filtration amount can be obtained even with a membrane regenerated by washing, and thus there is an effect that practical filtration becomes possible.

[Brief description of the drawings]

FIG. 1 is a graph showing a change over time in a filtration flow rate when a new membrane before regeneration is used.

FIG. 2 is a graph showing the change over time of the filtration differential pressure in the present invention, with the number of times of washing as a parameter.

FIG. 3 is a graph showing the change over time in the filtration flow rate when a new membrane before regeneration is used in Comparative Example 1.

FIG. 4 is a graph showing a change over time in a filtration differential pressure in Comparative Example 1 with the number of times of washing as a parameter.

FIG. 5 is a graph showing the change over time in the filtration flow rate when a new membrane before regeneration is used in Comparative Example 2.

FIG. 6 is a graph showing a change over time in a filtration differential pressure in Comparative Example 2 with the number of times of washing as a parameter.

FIG. 7 shows a schematic process for filtering with periodic backwashing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Filter housing 2, 3 ... Pump 4 ... Filtration stock solution 5 ... Filtrate storage tank 6 ... Backwash liquid

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-4-317723 (JP, A) Proc. Congr. Eur. Brew. Conv. , 15th, p. 201-216, 1975 (58) Fields studied (Int. Cl. ⁷ , DB name) C12C 1/00-13/10 C12H 1/00-1/22 JICST / JAFIC (JOIS)

Claims (3)

(57) [Claims] 1. A beer filtration method comprising: using a microfiltration membrane having an anisotropic pore diameter in the thickness direction of the membrane, and filtering the undiluted filtration solution with periodic backwashing, wherein A microfiltration membrane having an anisotropic pore size has a pore size of 4 at the inlet side surface where the undiluted filtrate first contacts the membrane.
３０30 μm, the pore diameter of the densest layer of the membrane is 0.8-4.0 μm
Wherein the undiluted filtrate to be filtered is a beer fermentation finished liquid produced using wort obtained by performing β-glucanase treatment in a preparation step for wort production. Beer filtration method. 2. The microfiltration membrane having an anisotropic pore diameter in the thickness direction of the membrane has a pore diameter of 24 to 30 μm on the inlet side surface where the undiluted filtrate first contacts the membrane, and a pore diameter of the densest layer of the membrane. 0.
The beer filtration method according to claim 1, wherein the thickness is 8 to 1.2 m. 3. The beer filtration method according to claim 1, wherein the microfiltration membrane having anisotropic pore diameter in the thickness direction of the membrane is a regenerated membrane regenerated by washing.