GB2323852A - Beer brewing process(es) - Google Patents

Abstract

The process(es) consist(s) of the following taken singly or in combination:- (a) a method and apparatus for making clarified wort for delivery to a fermenting vessel consisting of essentially two operating stages by means of a mashing vessel or tun 201 and a wort purifying device 202; (b) a method and apparatus for brewing beer from wort in essentially two stages consisting of a fermentation vessel 203 and a filtration device 204; and (c) a method and apparatus for reclaiming and recycling liquids used to wash and/or sterilise the vessels etc. Mashing, boiling and cooling may take place in a single vessel 201 and the purifying/filtration step may use a filter belt membrane providing sub-micronic separation. The fluids from the periodic cleaning and sterilising of apparatuses 201-204 and 211 are collected in receivers 209 and, after treatment, pumped to the pressure belt filter 211.

Description

WASTE ELIMINATING AND MORE COST-EFFECTIVE BEER BREWING PROCESS Desrnption Background: From a historical vantage point, the present day liquid processing industries have evolved from what were initially simple, mostly one-step manipulations of raw materials to achieve the final product to multi-stage, waste producing and energy consuming processes that are a major cause ofthe present world-scale pollution ofthe fresh and sea water resources as well as significant contributors to the continuing wastage ofthe world's natural energy resources.

One of the main reasons for this state of affairs is that much of the primitive initial technologies pertaining to the conversion and purification ofthe raw and production materials have been retained to the present day and progress has been and is perceived to be connected with the proliferation of further production stages to correct inadequacies in these antiquated methodologies instead their replacement with modern, improved technologies.

Goal of this invention: The goal is, with the aid of new technologies, to replace multi-stage, waste generating, high enegy consuming separation and purification operations by single-stage, waste minimizing and energy conserving systems in the main liquid processing industries such as the sugar, beverages, food and chemical industries and thereby convert raw materials to finished products far more directly and to purify the resulting minimized waste streams "in-situ" with the final goal of eliminating entirely the discharge of liquid effluent from liquid processing and using industries and reducing significantly the present generation of solidwaste.

The Invention: The invention will be elucidated by describing an innovative beer brewing process that can be applied to other related beverage industries, e.g. wine making, fruit juices, etc.

The technology of this sector of the liquid processing industry is clearly anchored in the past.

Fig. 1 illustrates how what was originally a stage process has now developed into a ca. 17-stage process. On analysis it is clear that the purification apparatuses depicted at 103,105,107,109,110,112,113,114,116,117 (10 separate separation stages) are the cause of this proliferation, These stages are also the cause of the present serious environmental pollution problem associated on a world-scale with beer brewing and wine making. Published figures indicate that for every litre of beer produced, 5 to 10 litres of high BOD wastewater are generated and often discharged untreated to drain. For example, in a typical top fermenting UK brewery producing 500hl of beer per hour (50m3/h), up to 500 m3 of wastewater often containing in excess of 3000 Vh of beer from lees (tank bottoms), wort, yeast sludges, etc. are discarded to drain. Further considerable product losses in the conventional brewing process start with losses of up to 20% of extract due to incomplete conversion of higher saccharides (e.g starch) into fermentable sugars in the mashing process followed by losses of up to 15% of the extracted, fermentable sugars (wort) from mashing in a filtration operation at 103 called ,Jautering", caused by inefficient washing of the bed of,,spent grain" with the generation of large quantities of high-bod effluent. Further considerable losses of extract known as "wort" occur in the remaining sfl separation operations at 105 and 107, where particulate hops and material often "hot break" (coagulated proteinaceous and other organic matter in the wort after boiling in the wort kettle) are separated. These losses become particularly significant at 107 where a so-called "whirlpool" method of separation is often employed. The end-product of this ,,brewer's wort" producing section of a typical brewery is a liquid containing the "cold-break", meaning the finely divided, suspended precipitate resulting from cooling the wort after the separation of the "hot-break", that mostly causes severe filtration difficulties later in the beer breweing process.

The product (beer) losses and accompanying generation of high-bod effluent are even more serious and significant in the beer producing section of a typical brewery: In the fermenter 109 the problematic of the ,,hazy" wort is added to by the excretion and precipitation of further ,intractable" proteinaceous and other organic matter by the multiplying yeast cells during the fermentation. The practice of either collecting and removing the yeast either at the top or bottom ofthe static" fermentation vats causes further problems pertaining to hygiene and beer quality. The "recovered" beer from yeast presses (if employed) 116 is of an inherently sub-standard quality due to degradation from contact with air and the impossible task of maintaining the presses in a sanitary condition. Recovered beer from such operations can be considered as worthless and is merely an added contribution to the high-bod effluent problem.

Large remnants of yeast cells normally cling to the lower and/or upper surfaces of the fermenter vats requiring large volumes of water to remove them as high-bod effluent.

The ,'green" beer in the fermenter is largely opaque with an intractable proteinaceous "haze" including remnant yeast cells in suspension. Some ofthis is often removed by plate-type centrifuges 110 resulting in a sludge that is impossible to filter without the addition of large quantities of filter aid such as diatomaceous earth. Mostly these types of sludges are put to drain. The centrifuged "green" beer, still containing the bulk of the intractable "haze" material in suspension (state of the art centrifuges mostly have a particulate ,,cut off point" in excess of 10 micrometers), is sent to large holding vessels 112 called conditioning tanks, lager tanks, maturing tanks, etc. where, in clarification/stabilisation operations, it is held for days, weeks or even months, normally at low temperatures. To accelerate the clarification process of ales in particular, it has become world-practice to add "fining material" such as naturally occurring gelatinous substances to the "green" beer. The resulting settled layer is impossible to filter directly and rather than incur large expenditure for filter aids that merely cause further large quantities of troublesome solidwastes and low quality recovered beer because ofthe inevitable exposure to air and the insanitary operations with the filter presses 417, these ,,tank bottoms" are often also put to drain. In excess of 3% of beer content of a brewery production is often lost in this way. Despite this "conditioning", colloidal and other finely divided materials still remain in suspension. A further centrifuging stage 113 is therefore mostly practiced, followed by a final "sterile" filtration operation 114, both of which generate large quantities of liquid- and solidwaste (filter aid and media).

Available statistics indicate a total loss of processed materials (potential packaged beer) in the average brewery of 10-20%. A rough estimate ofthe amount of high-bod effluent and therefore worldwide water consumption is 1.2 x 109 (ten billion) m3/annum. The total cost taking in lost processed materials, the cost of municipal water consumption and effluent treatment, runs into many tens of billions of US dollars/annum.

The goal of the present invention is to rationalize these processes and thereby cut these costs significantly.

The basic innovative ideas according to the invention to alleviate the present situation are the following: 1. To reduce the number of operating steps in the brewing process from ca. 17 to 4, thereby cutting the present average volume of brewery effluent and product losses by at least 80%, whereby the means are provided for recovering and recycling this significantly reduced effluent volume resulting in what is essentially zero effluent or effluent that is identical with the water supplied to the brewery.

2. To rationalize and improve the ,,brewer's wort" process by a) reducing the average particle size of the grain/malt raw materials for the mashing process considerably below that conventionally employed when using either the lauter tun or more recently filter press types of separators for filtration; b) providing heavy duty agitation facilites for the mashing operation with ajacketed (heating and cooling) reactor-type of pressure resisting vessel similar to those utilized in the chemical and pharmaceutical sectors as well as steam distillation equipment; c) optimizing the conditions of operation of these reactors to obtain the most rapid and thorough diffusional and mass-transfer processes possible in the production of brewer' s wort (including the extraction of hops) which in conjunction with the much finer comminution of the malt results in an anticipated +10% increase in the conversion yield of the mashing process, which in turn results in a much higher gravity wort and increases the productivity of the brewing process to the same degree; d) providing vacuum distillation for a short period at the end phase of the mashing process to reduce the maximum operating temperatures in the production of brewer's wort to ca 80oC and achieve the desired wort quality without the conventional high energy consuming practice of boiling wort at atmospheric pressure or above for relatively long periods (hours); e) cooling the resulting wort suspension (mash) .to ensure the maximum precipitation of unwanted substances still in solution at the higher temperatures, thus achieving the conventional "cold break" before the lautering or filtration operation; f) ,,sterile"-filtering the resulting cooled suspension using filter medium (e.g. membranes) with an optimized particle size "cut-off' while using the finely divided husks and non-fermentable insoluble material as filter aid and adsorbent for the purification operation and to wash the resulting filter cake with a minimum amount of water to achieve the maximum amount of extract from the said cake before dewatering and discharging same; g) to direct the clarified, filtered wort through sterile conduits to sterilized reactors for fermentation.

3. To rationalize and improve the process from fermentation to packaging by a) conducting the fermentation in such a way, that with the addition of suitable inert adsorbent materials using reactors ofthe same general design as described above, the clarity of the fermenting solution surrounding the yeast cell population as well as the adsorbent particulate matter remains substantially constant during the entire fermentation process; b) controlling the rate of the mass transfer mechanisms associated with the fermentation with an optimal degree of agitation and contact time as well as temperature and pressure control of the contents ofthe reactor dunng the fermentation to ensure the optimal degree of metabolic conversion required from the yeast cells and the adsorption ofthe undesirable by-products (especially those substances that cause subsequent instability and off-flavor with present fermentation practices) by the adsorbent materials; c) filtering the contents of the reactor held in an agitated state by means of sterile equipment utilizing membraneous filter medium with a particle-size "cut-offs' (retention) of ca. 0.1-1.0 microns, whereby the cake, consisting of yeast cells and adsorbent material, is washed with sterile, purified water to recover much ofthe residual beer in its interstices.

Fig. 1 is a schematic representation of the innovative beer brewing process according to the invention to achieve this goal: According to the invention, apparatuses 101,102,103,104,105,106,107,108 (Fig. 1) of conventional wort processing will be replaced essentially by apparatus 201,202 depicted in Fig. 2. The operations now carried out in conventional breweries at 101,102,104,106,108 will be accomplished in apparatus 201 ofthe invention. Apparatus 201 preferably takes the form of a conventional reactor in the chemical and pharmaceutical industry. Fabricated out of stainless steel or glass lined mild steel, the apparatus is certified as a coded pressure vessel fitted with a jacket 213 for heating and cooling the contents and a heavy duty agitator 214 as well as vacuum distillation equipment 216 consisting of an internal steam sparging device with external condenser and vacuum pump. The purpose ofthis equipment is to provide an alternative to ,,wort boiling" at 104 in the conventional process. According to the invention, removal of undesirable organic volatiles, which is the one of the main purposes of,,boiling" process, can be achieved far more efficiently with considerable economies in heating costs and at a much lower temperataure by means of steam distillation either,,in situ" in the mashing reactor 213 or externally in a separate vessel after lautering. The fUrther key to the wort process according to the invention is the provision of apparatus 202, which preferably takes the form of a pressure belt filter described in UK Patent GB 2280857. This apparatus, in contrast to the conventional filter apparatuses in the brewing process depicted at 103, is capable of operating at pressures up to 10 bar and can filter and thoroughly "wash" (recovery of extract) the "spent grain" resulting from finely ground malt (av. particle size approx. 10-50 microns). The thin beds of extremely fine mash solids formed on the belt of the pressure filter result in high washing "extract" efficiencies. "Extract efficiency" is the % recovery in the lautering or filtration operation of the extract (wort) obtained in the mashing process. An increase of at least 100/o compared to conventional lautering apparatus is anticipated with the apparatus of the invention. An overall increase in the yield of fermentable carbohydrates with the apparatus and method of the invention of +20% is therefore anticipated, which means in effect a similar increase in the yield of bottled beer. A comparable increase in the "gravity" (concentration of dissolved fermentable matter) of the recovered wort is also anticipated. This apparatus not only replaces the conventional apparatus depicted at 103,105,107 but also removes the fine precipitate resulting from chilling wort to below room temperature in the reactor 201 (the finely ground malt provides fine husk and other extraneous matter that acts as an effective filter aid) which in conjunction with the membraneous filter belt ensures that the wort going to the fermenters is in a "sterile" condition that cannot be guaranteed in the conventional ,,brewer's wort" process. Additionally, the ,,brewer's wort" process according to the invention reduces considerably the wort losses that now take place with the hops strainer 105 and the centrifuge or "whirlpool" 107.

According to the invention, apparatuses of the conventional fermentation process depicted in Fig.1 at 109,110,111,112,1.13,114,115,116,117 will be replaced essentially by two units of apparatus, namely, 203,204 depicted in Fig. 2.

The essence of this innovation is in the realization that the purpose of this array of apparatus is to purify and sterilize the fermented wort in the fermenter 109. The array can be explained, firstly, in that the wort introduced to the fermenter not only contains a proteinaceous-type "haze" in suspension but also contains colloidal and further substances in solution that precipitate or coagulate after fermentation. The invention provides the means for not only removing the remaining unwanted soluble substances in the wort causing subsequent instability but also to remove the unwanted components of the soluble proteinaceous and other organic matter resulting from the metabolic processes of the yeast cells during fermentation which also cause subsequent instability as well as off-flavor. According to the invention it is proposed to "stabilize" the products of fermentation, preferably in the fermenter itself by introducing suitable adsorbent materials such as synthetic or natural aluminosilicates, silica gels, aluminas, resins, etc. before and/or during and/or after the fermentation and to utilize to the full the natural clarifying properties of certain strains of suspended (agitated), fresh, healthy yeast cells to render the fermented wort (beer) clear and stable. One specific role of these adsorbents is to remove diacetyl and its precursors alpha-acetolactate, whereby the natural capacity of the yeast cells when kept in intimate contact with the contents of the reactor (agitation) to convert diacetyl to acetoin is fully utilized by the method and apparatus of the invention.

Beer brewing is largely an impirical process. Theories abound, but the main requirement in practice is the capability of reproducing results once a formular for good brewing has evolved.

There is insufficient control over the fermentation process in conventional brewing to guarantee the reproducibility of results. According to a further innovation of the invention, in effect, the rate of generation of carbon dioxide in the fermentation process is measured and controlled to adhere to an empirically determined regime. According to invention, the evolution of carbon dioxide (rate of fermentation) is controlled by means of a) . a gas now controller 218 regulating the supply of heating or cooling medium to the jacket of the fermenter 203 during the fermentation by means of control valve 219 and/or b) the control of the pressure within the fermenter 203 by means ofthe pressure controller 220 regulating the gas flow control valve 221.

The adsorbent material is preferably introduced to the fermenter from the holding tank 205.

This material may be sized and shaped to act as a filter aid for the direct filtration of the chilled contents offermentp 203 perferably by means of a pressure belt filter described in PS GB 2280857. the advantage of this and the absence of precipitated/coagulated proteinaceous and other matter in the beer according to the invention, is that comparatively high rates of filtration will be possible. Specific rates of filtration in the region 5-15 m3/m2h are envisaged. These through-puts, according to the invention, are associated with relatively short cycle time of the order of 30 minutes. Such cycles are only possible with the filter apparatus according to the invention.

The direct filtration of the suspended yeast and adsorbent material with the subsequent displacement washing ofthe filter bed by means ofthe filter apparatus 204 means that the sterility and wastesludge problems with centrifuges 110 and 112 as well as the long hold-times and the voluminous, slimy settled material associated with the conditioning tanks 112 are eliminated. It is further proposed, that the filter apparatus 21 lis fitted with a filter belt composed of membranous material providing particle size retention in the sub-micronic region and thus sterile filtration. According to the invention the possibility is provided for bottling direct from the fermenter tank 203 thus eliminating costly, space consuming lager and conditioning tanks. The further advantage of the process of the invention is that the troublesome final precoat filtration stage using filter aid or filter sheets 114 of conventional brewing, with the inherent sanitary and sludge discharge porblems, are eliminated.

The final overriding advantage of the process of the invention is that the volume and the degree of contamination (suspended matter and dissolved organic substances, BOD) of the resulting wasteliquid compared with conventional brewing are considerably reduced (estimated +95% reduction) with the possibility of it being completely eliminated.

The above described innovative brewing process provides the prerequisites for completely solving the world-scale problems associated with brewery effluent discharge and solidwaste disposal. Attempts to solve these problems while retaining the conventional brewing process illustrated on Fig.1 have failed. The reason for this can be seen in the sheer magnitude of the task of treating the large volumes of liquidwaste with a high BOD consisting of suspended and dissolved organic matter generated by the conventional methods of brewing. In effect, to solve the problem applying state-of-the-art technology, each brewery would be obliged to invest in ist own medium sized sewage works.

In the wort and beer brewing process depicted in Fig.2 there are no sludge discharges caused by the process itself and apart from the "spent grain" from the wort process and the solid yeast from the brewing process (both of which can be mixed and used directly for cattle fodder), solidwaste is largely eliminated. First of all, the yeast cells and adsorbent material of the filter bed are discharged as a composite filter cake by 204 and are either disposed of directly as cattle fodder or the components are separated in the regenerator 206, whereby the adsorbent material is regenerated and the adsorbate and yeast are discharged to 208 for yeast dewatering. The aqueous fraction is forwarded to the wash liquid receiver 209 from where soiled sterilizing and washing liquids are purified by means of a pressure belt purification apparatus 211 similar to 202 and 204. As with these, the belt of211 is composed of membranous sections providing particulate retention in the sub-micronic region.

According to the present invention, the single requirement to eliminate liquid effluent is to purity and reuse the fluids imployed for periodically washing and sterilizing the equipment illustrated on the flow-sheet (Fig. 2), whereby the much reduced quantities of suspended and dissolved organic matter are removed directly in apparatus 211 producing solid waste suitable for incineration. The fluids from the periodic cleaning and sterilizing of apparatuses 201, 202, 203, 204, 211 are collected in the soiled wash liquid receivers 209 from where, after batchwise pH adjustment and dosing with flocculating and adsorbent material, they are pumped to the pressure belt filter 211 together with dosed granular media from 212 with suitably charged surfaces. The flocculated suspended and colloidal matter in the washing and/or sterilizing fluids as well as the flocculated finely divided sorbent material either become attached by electrostatic resp. electronic forces to the surfaces of the forming bed of granular material or are entrapped in its interstices. The purified fluids finally pass through a membraneous section of filter belt that also acts as a support for the filter bed and are delivered as sterile filtrate to the sterile wash liquid reservoir 210 for recirculation to the said apparatuses.These are equiped internally with manifolds fitted with nozzles, such as depicted at 215, suitable for the transmittal of high velocity jets with delivery pressures of up to 200 bar. These manifolds rotate during operation, whereby the nozzles are situated so that the high velocity jets reach all internal and external surfaces of the filter chamber and the internal surfaces of the chamber housing. This type of "in-place" cleaning apparatus is installed in all vessels of the brewing process of the invention, filter apparatuses and process vessels. The pressure belt filters 202, 204, 211 are designed to maintain internal sanitary conditions in fully automatic operation.

Their general design and operation conform with the filter apparatuses described in Patent Specification GB-2280857 "A Belt Filter" and GB PA 9605556.1, "Apparatus and method concerning a moving belt filter for liquids". The liquid purifying apparatus 211 and method conform with the apparatus and method described in the German Offenlegungsschrift DE 18534102A1, ,,Ein System der Fliissigkeitsaufbereitung".

One end ofthe filter apparatus is reserved for the discharge ofthe deep-beds of filter media to the bed regenerator 213. The other end is reserved for the discharge of solid products in the form of a filter cake as required.

Claim, 1. A process for brewing beer consisting of the following apparatuses and methods taken singly or in combination: method and apparatus for making clarified wort for delivery to a fermenting vessel consisting of essentially two operating stages by means of a mashing vessel (201) and a wort purifying device (202); method and apparatus for brewing beer from wort for direct packaging and direct consumption in essentially two stages consisting of a fermentation vessel (203) and a beer filtration device (2Q4); method and apparatus for reclaiming and recycling liquids used to wash and/or sterilize apparatuses and vessels employing the means (211, 212, 213).

2. An apparatus for producing brewer's wort according to Claim 1, thereby characterized, that the mashing vessel or mash tun (201) is designed to withstand non-atmospheric pressure and is provided with the means (216) for sparging live steam into the fluid contents of the said mash tun.

3. An apparatus for producing brewer s wort according to Claim 2, thereby characterized, that the mashing vessel or mash tun (201) is provided with the means (216) for creating an under-pressure (vacuum) in the said vessel and simultaneously condensing the exiting live steam of the said sparging operation.

4. Method and apparatus for producing sterile and clarified brewer's wort according to Claim 1, thereby characterized, that the operations of mashing, boiling and cooling take place in a single vessel (201) and that the lautering (filtration) step, as the second and final operation, is carried out using a membraneous section of filter belt of the liquid purification apparatus (202) providing sub-micronic separation.

5. An apparatus for producing fermented wort (beer) according to Claim 1, thereby characterized, that the fermenting vessel (203) is designed to withstand non-atmospheric pressure and is provided with the means (220, 218, 221, 219) for controlling the pressure and/or temperature of the contents of the said fermenting vessel during the fermentation operation, whereby the rate of evolution of carbon dioxide within the fermenting vessel during the fermentation operation is regulated to control the rate of fermentation.l 6. Method and apparatus for producing fermented wort (beer) according to Claim 1, thereby characterized, that sorbent material capable of adsorbing dissolved, haze-producing material either in the wort or produced during the fermentation is introduced to the fermenting vessel (203) before and/or during and/or after the fermentation process and that the means are provided to keep the solids (including the yeast cells) in the fermenting vessel suspended during the whole fermentation process.

7. Method for producing fermented wort (beer) according to Claims 1 and 6, thereby characterized, that the operations of fermentation, clarification, conditioning and stabilization take place in a single vessel (203) and in a single operation before and/or during and/or after the fermentation.

8. Apparatus and method for purifying fermented wort (beer) according to Claim 7, thereby characterized, that the second and final operation is carried out using a membraneous section of filter belt of the liquid filtering apparatus (204) providing sub-micronic separation.

9. Apparatus and method for reclaiming and recycling liquids used for washing and sterilising apparatuses and vessels of the brewing process according to Claim 1, thereby characterized, that after pH adjustment and dosing with flocculating material as well as sorbent material the liquids are passed through beds of surface-charged granular material in apparatuses such as (211).

10. Apparatus according to Claim 9, thereby charact

Claims (7)

1. AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWS

   Claims 1. A process for the production, clarification and purification of wort and beer utilizing membranous filter media affording sub-micronic, sterile separation and thereby achieving significant cost savings and reduction in the environmental pollution caused by the conventional brewing process, thereby characterized, that band filters 202, 204 with a filter chamber through which a filter band capable of sub-micronic separation is intermittently transportable over a support surface that divides the filter chamber into a lower filtrate chamber and an upper turbid liquid chamber, whereby the turbid liquid chamber has a lid-like form and the filter band during the operation when a pressure differential in the filter chamber develops is sealed between the movable dependent edges of the turbid liquid chamber, are employed for the clarification of the processed liquids, namely wort and beer.
2. 2. A process according to Claim 1, thereby characterized, that mash for filtering to produce wort is made from ground malt and/or grain with a mean particle size considerably below that conventionally employed when using either the lauter tun or the more recent filter press-type of separators.
3. 3. A process according to Claim 1, thereby characterized, that the mash after heating is subjected to vacuum and blown with live steam while under vacuum.
4. 4. A process according to Claim 1, thereby characterized, that the mash after heating is cooled to produce the cold-break before filtration.
5. 5. A process according to Claim 1, thereby characterized, that in order to maintain clarity in the fermenting wort and obtain clarified and stabilized fermented beer, the wort before and during fermentation is dosed with adsorbent material such as silica, resins, zeolites, etc. to remove haze and off-taste producing substances already in solution in the clarified wort and produced metabolically by the yeast cells during fermentation.
6. 6. A process for the fermentation of beer according to Claim 1, thereby characterized, that the fermentation in the fermenter 203 is controlled by a programmed relationship between temperature, pressure and carbon dioxide evolution during the course of the fermentation.
7. 7. A process for reclaiming and recycling recovered liquids from the beer production process, thereby characterized, that a band filter or filters 211, with a filter chamber through which a membranous filter band capable of sub-micronic filtration is intermittently transportable over a support surface that divides the filter chamber into a lower filtrate chamber and an upper turbid liquid chamber, whereby the turbid liquid chamber has a lid-like form and the filter band during the operation when a pressure differential in the filter chamber develops is sealed betwen the movable dependent edges of the turbid liquid chamber and the filtrate chamber, are employed for the purpose of purifying and recycling effluents produced in the brewing process.