A gas-assisted hydrodynamic cavitation hop treatment method and device, and a beer brewing system

Abstract

The application discloses a kind of gas-assisted hydrodynamic cavitation hop processing method and device, beer brewing system, it is related to beer brewing process and liquid phase chemical conversion technical field, the method includes the following steps: after hop is added to water, inert gas is injected to carry out hydrodynamic cavitation extraction and solid-liquid separation, and extraction liquid is obtained;The extraction liquid is mixed with the part of hot wort taken out from boiling stage to form carrier system, and is carried out cavitation isomerization treatment under the action of divalent metal ion catalyst and carbon dioxide, and isomerization liquid is obtained;The isomerization liquid is added back to the hot wort in boiling stage, and dilution, pH natural neutralization and residual isomerization are completed.Compared with prior art, the application can realize α-acid isomerization rate ≥70% and linalool system utilization rate ≥45% simultaneously within 30 minutes, greatly shorten process time and save energy, solve the fundamental contradiction that α-acid isomerization and linalool retention process condition is opposite.

Description

Technical Field

[0001] This invention relates to the fields of beer brewing technology and liquid-phase chemical conversion technology, and particularly to a gas-assisted hydraulic cavitation hop treatment method and apparatus, and a beer brewing system. Background Technology

[0002] Traditional beer brewing requires boiling at approximately 100°C for 60-90 minutes to achieve the isomerization of α-acids in hops, which presents the following prominent problems: (1) High energy consumption: long-term boiling consumes a large amount of steam, and the utilization rate of α-acid is only about 30-35%; (2) Severe loss of aroma: During the open boiling process, water vapor entrainment leads to a loss of up to 80-90% of heat-sensitive aroma components such as linalool ((R)-linalool, with a sensory threshold as low as about 2.2 μg / L), and significant loss of hop aroma. Summary of the Invention

[0003] To address the aforementioned problems, this invention provides a method and apparatus for treating hops using air-assisted hydraulic cavitation, and a beer brewing system.

[0004] In a first aspect, the present invention provides a method for treating hops using air-assisted hydraulic cavitation, such as... Figure 1 As shown, it includes the following steps: After adding hops to water, an inert gas is injected to perform hydraulic cavitation extraction and solid-liquid separation to obtain the extract. The extract is mixed with a portion of hot wort taken from the boiling stage to form a carrier system, and then subjected to cavitation isomerization treatment under the action of divalent metal ion catalyst and carbon dioxide to obtain an isomerized liquid. The isomerized liquid is added back to the hot wort that is in the boiling stage to complete dilution, natural pH neutralization and residual isomerization.

[0005] Furthermore, the operating conditions for the hydrocavitation extraction include: pH 7.6-8.0, temperature 80-95℃, and time 5-25 min. The operating conditions for the cavitation isomerization treatment include: pH 6.5-7.5, temperature 95-100℃, and time 20-40 min.

[0006] Furthermore, during the hydrocavitation extraction, The weight ratio of the hops to the water is (1~2):(10~20), and the gas-liquid ratio of the system after the inert gas is injected is 2-5%.

[0007] Furthermore, during the cavitation isomerization process, After the carbon dioxide is injected, the gas-liquid ratio of the system is 1-3%, the weight ratio of the extract to the hot wort is (1-2):(2-10), and the concentration of the divalent metal ion catalyst in the system is 100-300 ppm.

[0008] Furthermore, the inert gas includes at least one of nitrogen and argon, and the hops include at least one of T90 particles, T45 particles, and CO2 hop extract; The divalent metal ion catalyst includes at least one of magnesium ions, calcium ions, and zinc ions.

[0009] Furthermore, within 30 minutes, both α-acid isomerization rate ≥70% and linalool system utilization rate ≥45% can be achieved simultaneously.

[0010] Secondly, based on the same inventive concept, the present invention provides an air-assisted hydraulic cavitation hop treatment apparatus for implementing the air-assisted hydraulic cavitation hop treatment method described in any one of the first aspects, comprising: Mother liquor tank, used to prepare and contain alkalization extraction mother liquor; The first circulation loop includes a first circulation pump and a first hydraulic cavitation device. The first hydraulic cavitation device is provided with an inert gas injection port, and the loop returns to the mother liquor tank. A solid-liquid separator is connected to the first circulation loop and outputs a solid-free extract. The isomerization reaction vessel is sealed and equipped with back pressure exhaust, and is connected to the main boiling pot via insulated pipeline. The second circulation loop includes a second circulation pump, a heat exchanger and a second hydraulic cavitation device. The second hydraulic cavitation device is equipped with a CO2 gas injection port. The loop returns to the isomerization reaction tank. The feeding system adds pH adjuster and divalent metal ion catalyst to the mother liquor tank and the isomerization reaction tank, respectively. The control system is connected to sensors and actuators for temperature, pH, flow rate, and gas injection volume.

[0011] Furthermore, the side-flow module accounts for 0.3%-1.5% of the main boiling pot capacity; The first hydraulic cavitation device and the second hydraulic cavitation device each independently include a Venturi-type hydraulic cavitation device, wherein the throat area ratio of the Venturi-type hydraulic cavitation device is 9%-12%; the gas is self-drawn in by the negative pressure of the throat, without additional pressurization equipment.

[0012] Furthermore, it also includes a gas recirculation system that recovers the exhaust gas from the isomerization reactor and sends it back to the injection port of the second cavitation unit.

[0013] Thirdly, based on the same inventive concept, the present invention provides a beer brewing system, including a mash tun, a boiling tun, and the air-assisted hydraulic cavitation hop treatment device described in any of the second aspects, wherein the air-assisted hydraulic cavitation hop treatment device is installed as a side-flow module between the mash tun and the boiling tun in the beer brewing process.

[0014] The technical solutions provided in the embodiments of the present invention have at least the following advantages compared with the prior art: This invention provides a method and apparatus for treating hops using air-assisted hydraulic cavitation, and a beer brewing system. Compared to existing technologies, this invention can simultaneously achieve an α-acid isomerization rate of ≥70% and a linalool system utilization rate of ≥45% within 30 minutes, significantly shortening process time and saving energy. It also resolves the fundamental contradiction between the opposing process conditions for α-acid isomerization and linalool retention. Specifically: The beneficial effects of the process method include: (1) Quantitative indicators: The α-acid isomerization rate ≥70% and the linalool system utilization rate ≥45% can be achieved simultaneously within 30 minutes, which is impossible to achieve with existing technologies; (2) The process time is greatly shortened: compared with the traditional boiling time of 60–90 minutes and Cavibeer's time of 90–140 minutes, this process takes only about 30 minutes and runs in parallel with the main boiling pot, without increasing the total brewing time; (3) Significant energy savings: Taking a brewery with an annual output of 200,000 tons as an example, it saves about 9,000 tons of industrial steam, about 680,000 m³ of natural gas, and about 827 tons of standard coal per year, and saves about 29% of boiling energy consumption; (4) Linalool retention rate is significantly improved: With the help of Henry balance in a closed loop, the evaporation loss of linalool at 98°C / 30 minutes is only about 1.8%, which is far lower than the loss of 80-90% in traditional open boiling; (5) Hop usage is reduced by 35–50%: α-acid utilization is increased from about 30% to 55–65%, and hop usage is significantly reduced for the same IBU target.

[0015] The beneficial effects of the device include: (1) Sidestream module architecture: It only processes concentrated mother liquor accounting for 0.3%–1.5% (preferably 0.7%±0.1%) of the total volume of cold wort in the main boiling pot, so that the pH, catalyst and gas environment of the mother liquor system can be independently optimized without affecting the wort composition in the main boiling pot. (2) pH engineering: The pH of the carrier system was adjusted to 7.0–7.5. By utilizing the pH dependence of the Henderson-Hasselbalch equation, the α-acid isomerization rate k1 was increased by about 6.25 times compared with the natural pH of the wort. (3) Divalent metal ion catalysis: Adding Mg 2+100–300 ppm, through Lewis acid mechanism, coordinates with α-acid enol salt to form a five-membered chelate ring, further increasing k1 by 1.5–2.0 times; (4) Step-by-step gas selection and gas assistance: N2 is injected in the extraction step (adiabatic index γ=1.40, strong mechanical effect promotes extraction), and CO2 is injected in the isomerization step (γ=1.30, mild collapse protects iso-α-acid products) - different gases are selected in different steps of the same device; (5) Closed-loop architecture: The isomerization step adopts a closed loop with a back pressure of 0.2–0.5 bar, and the cumulative evaporation loss of linalool over 30 minutes is strictly limited to about 1.8% by utilizing Henry's equilibrium of linalool.

[0016] (6) The equipment includes: air-assisted hydraulic cavitation; Venturi cavitation area ratio of 9–12%; gas is drawn in by negative pressure through the Venturi throat (no pressurization equipment required); and PLC achieves self-testing function with dual indicators. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a gas-assisted hydraulic cavitation hop treatment method provided in an embodiment of the present invention.

[0020] Figure 2 The diagram shows the structure and process flow of the air-assisted hydraulic cavitation hop treatment device provided in a preferred embodiment of the present invention.

[0021] Figure 3 A process flow diagram of the gas-assisted hydraulic cavitation hop treatment method provided in a preferred embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Unless otherwise specified, all raw materials, reagents, instruments, and equipment used in this invention can be purchased commercially or prepared using existing methods. Furthermore, unless otherwise specified or detailed, the steps and parameters involved can be performed according to conventional processes and parameters disclosed in the prior art, or directly using existing equipment according to the instruction manual; these will not be elaborated upon further in this invention document.

[0024] Existing technologies cannot simultaneously achieve both α-acid isomerization rate ≥70% and linalool system utilization rate ≥45% within a single process step and within 30 minutes. The fundamental contradiction lies in the fact that α-acid isomerization requires high temperature, high pH, ​​and long time, while linalool retention requires low temperature, short time, and low gas-liquid contact area. The two process conditions are opposite, making it difficult to achieve both within the same process window.

[0025] To solve the above-mentioned technical problems, the present invention provides the following technical solution: As a preferred embodiment, an apparatus is provided, such as Figure 2 As shown, this device, as a side-flow module, is installed as a whole between the existing mash tun and boiling kettle in the brewery. It serves as an add-on unit without replacing existing equipment, and the module's volume is only 0.3%–1.5% (preferably 0.7% ± 0.1%) of the mash tun's capacity. The device mainly consists of the following components: (i) Mother liquor tank V-101: Atmospheric pressure stainless steel tank with jacket insulation and vent at the top, used to prepare and contain alkalization extraction mother liquor; (ii) First circulating pump P-101 and first Venturi-type hydraulic cavitation unit CV-101: The outlet of P-101 is connected to the inlet of CV-101 via a pipeline. The throat diameter of CV-101 is 8–80 mm (depending on the scale) and the area ratio is 9–12%. An N2 gas injection port of Ø2–5 mm is provided at its throat or 5–20 mm downstream of the throat. This injection port is connected in sequence to an N2 gas source, a pressure reducing valve, a check valve and a flow meter. The outlet of CV-101 flows back to V-101, forming the first circulation loop. (iii) Solid-liquid separator CS-101: Selected from hydrocyclone separator or centrifugal separator, its inlet is connected to the first circulation loop, used to separate hop solids and output extract without solids; (iv) Isomerization reactor V-102: atmospheric pressure closed design with 0.2–0.5 bar back pressure exhaust, 316L stainless steel, equipped with pH, ​​temperature and liquid level online monitoring instruments, and connected to the main boiling pot through insulated pipeline, used to contain the mixture of extract and carrier wort and carry out isomerization. (v) Second circulation pump P-104, plate heat exchanger HX-102 and second venturi-type hydraulic cavitation unit CV-102: The outlet of P-104 is connected in sequence to HX-102 (maintaining 98°C±1°C), CO2 injection point and CV-102; the throat diameter of CV-102 is 10–100 mm (depending on scale), the area ratio is 9–12%, and the throat is equipped with a CO2 gas injection port of Ø3–6 mm; the outlet of CV-102 returns to V-102, forming a second circulation loop; the return pipeline of V-102 is preferably connected tangentially to the upper part of V-102 to promote the separation and recovery of undissolved gas; (vi) Feeding system: including pH adjustment system (containing KOH or phosphate solution feed pump) and Mg 2+ The catalyst feeding system (including a MgCl2 or MgSO4 solution feeding pump) feeds pH adjuster and catalyst into V-101 and V-102 respectively; (vii) PLC control system: connected to temperature, pH, flow rate, and gas injection quantity sensors / actuators to realize online monitoring and control, and has a self-test function that achieves dual indicators of α-acid isomerization rate ≥70% and linalool system utilization rate ≥45%.

[0026] Preferably, the device further includes a CO2 recovery and circulation system, which re-transports the CO2 discharged from the exhaust port of V-102 to the gas injection port of CV-102 to achieve internal CO2 circulation; both N2 and CO2 are introduced by negative pressure self-priming in the venturi throat, without the need for additional gas pressurization equipment; the flow velocity in the throats of CV-101 and CV-102 is 20–30 m / s.

[0027] As a preferred embodiment, such as Figure 3 As shown, this device employs a two-step process: Step 1 (N2-assisted cavitation extraction): Add softened water to the mother liquor tank V-101 and heat to 80–95°C. Adjust the pH to 7.6–8.0 with KOH and add T90 hop granules. Start P-101 to circulate the mother liquor through CV-101 for 5–25 minutes. Use the negative pressure at the throat to self-absorb N2 (gas-liquid ratio 2–5%), forming a large number of N2 nuclei in the liquid to enhance the cavitation mechanical effect, so that α-acids and linalool are efficiently released from the hop glands into the aqueous phase. Then, remove the hop solids by solid-liquid separation in CS-101 to obtain the α-acid / linalool extract.

[0028] Step 2 (CO2-assisted closed-loop cavitation isomerization): The extract is mixed with hot wort taken from the main boiling vessel in V-102 to form a carrier system. The pH is adjusted to 6.5–7.5 with KOH, and MgCl2 is added to make Mg... 2+Concentrations reach 100–300 ppm; P-104 is activated to sequentially pass the mixture through HX-102 (maintained at 98°C), the CO2 injection point, and CV-102 in a closed-loop system for 20–40 minutes, with a CO2 gas-liquid ratio of 1–3%. During this process: CO2 microbubbles, acting as cavitation nuclei, can reduce the cavitation threshold by 15–40%, increase the bubble frequency by 2–3 times, and lower the peak bubble collapse temperature from approximately 1500 K in pure cavitation to approximately 726 K, inhibiting iso-α-acid thermal degradation; Mg 2+ Linalool forms a five-membered chelate ring through coordination with α-acid enol salt via the Lewis acid mechanism, reducing the isomerization activation energy from 98.6 kJ / mol to approximately 80–85 kJ / mol; pH 7.2 ensures over 99% ionization of the α-acid, increasing the isomerization rate k1 by approximately 6.25 times compared to the natural pH of the wort; under closed-loop circulation, linalool is strictly limited by Henry equilibrium (dimensionless gas-liquid partition coefficient K_c≈0.019, evaporation loss per cycle is approximately 0.03%, and cumulative evaporation loss over 30 minutes is only approximately 1.8%); CO2 simultaneously replaces dissolved oxygen, preventing the oxidative degradation of α-acid and iso-α-acid.

[0029] Re-addition and merging: After the treatment is completed, the isomerized liquid is added back to the main boiling vessel to complete the dilution, natural pH neutralization and residual isomerization in parallel with the ongoing DMS boiling stage.

[0030] The above-mentioned device achieves dual targets through the synergistic effect of five process elements: ① side-flow module architecture (processing only about 0.7% of the batch volume, allowing pH / catalyst / gas environment to be optimized independently); ② pH engineering; ③ divalent metal ion catalysis; ④ stepwise gas selection and gas assistance (N2 extraction, CO2 isomerization); ⑤ closed-loop architecture (Henry balance protection of linalool).

[0031] In addition, the above (1) divalent metal ion catalyst: except for Mg 2+ In addition, Ca can be used. 2+ Zn 2+One or more of the following: (1) Magnesium source: MgCl2 or MgSO4; (2) Extraction step gas: In addition to N2, Ar or other inert gases with high adiabatic index can be used; (3) Hop form: T90 particles, T45 particles, CO2 extract or a combination thereof; (4) Solid-liquid separator: Cyclone separator or centrifuge separator; (5) pH adjuster: KOH or phosphate solution; (6) Gas injection location: Can be located at the venturi throat or 5–20 mm downstream of the throat; (7) CO2 source and recovery: Food-grade CO2 cylinders or brewery's own CO2 recovery system can be used, and an internal CO2 recycling system can be added; (8) Applicable scale: Saccharification pot scale 10–300 tons, annual production 50,000–1,000,000 tons; (9) Applicable products: Target beer bitterness IBU 3–100, including but not limited to Lager, IPA, Pilsner, Pilsner, Stout, Ale, etc., especially suitable for craft beer differentiation products that need to retain floral aromas.

[0032] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Experimental methods in the following embodiments, unless otherwise specified, are generally performed according to national standards. If no corresponding national standard exists, then generally accepted international standards, conventional conditions, or conditions recommended by the manufacturer are followed.

[0033] Example 1 This example provides a method and apparatus for treating hops using air-assisted hydraulic cavitation, such as... Figure 2 and Figure 3 As shown, it includes: Step 1 (N2-assisted cavitation extraction): Add softened water to the mother liquor tank V-101 and heat to 90°C. Adjust the pH to 7.8 with KOH and add T90 hop granules (the weight ratio of T90 hop granules to softened water is 1:10). Start P-101 to circulate the mother liquor through CV-101 for 5 minutes. Use the negative pressure at the throat to self-absorb N2 (3% gas-liquid ratio) to form a large number of N2 nuclei in the liquid to enhance the cavitation mechanical effect, so that α-acids and linalool are efficiently released from the hop glands into the aqueous phase. Then, remove the hop solids by solid-liquid separation in CS-101 to obtain the α-acid / linalool extract.

[0034] Step Two (CO2-Assisted Closed-Loop Isomerization): The extract and hot wort from the main boiling vessel are mixed in a 1:4 weight ratio in V-102 to form a carrier system. The pH is adjusted to 7.2 with KOH, and MgCl2 is added to make Mg... 2+The concentration reached 240 ppm; P-104 was activated to sequentially pass the mixture through HX-102 (maintained at 98°C), the CO2 injection point, and CV-102 in a closed-loop system for 20 minutes, with a CO2 gas-liquid ratio of 2%. During this process, CO2 microbubbles, acting as cavitation nuclei, lowered the cavitation threshold, increased the bubble frequency, and reduced the peak bubble collapse temperature from approximately 1500 K in pure cavitation to approximately 726 K, inhibiting iso-α-acid thermal degradation; Mg 2+ Linalool forms a five-membered chelate ring through coordination with α-acid enol salt via the Lewis acid mechanism, reducing the isomerization activation energy from 98.6 kJ / mol to approximately 80–85 kJ / mol; pH 7.2 ensures over 99% ionization of the α-acid, increasing the isomerization rate k1 by approximately 6.25 times compared to the natural pH of the wort; under closed-loop circulation, linalool is strictly limited by Henry equilibrium (dimensionless gas-liquid partition coefficient K_c≈0.019, evaporation loss per cycle is approximately 0.03%, and cumulative evaporation loss over 30 minutes is only approximately 1.8%); CO2 simultaneously replaces dissolved oxygen, preventing the oxidative degradation of α-acid and iso-α-acid.

[0035] Re-addition and merging: After the treatment is completed, the isomerized liquid is added back to the main boiling vessel to complete the dilution, natural pH neutralization and residual isomerization in parallel with the ongoing DMS boiling stage.

[0036] Thus, this example achieves both an α-acid isomerization rate of ≥70% (specifically 76.8% in this example) and a linalool system utilization rate of ≥45% (specifically 51.2% in this example) within 30 minutes.

[0037] Comparative Example 1 The difference between this example and Example 1 is that: (1) Step 1 is N2-free cavitation extraction, that is, no N2 gas is injected during hydro-cavitation extraction. The remaining steps and parameters are the same as in Example 1.

[0038] The specific process steps and parameters of the above preparation process include: Step 1 (Pure water cavitation extraction, without N2 gas): Softened water is added to the mother liquor tank V-101 and heated to 90°C. The pH is adjusted to 7.8 with KOH, and T90 hop pellets are added (the weight ratio of T90 hop pellets to softened water is 1:10). P-101 is started to circulate the mother liquor through CV-101 for 5 minutes. No N2 gas is injected throughout the process; extraction is carried out solely by pure water cavitation. Subsequently, hop solids are removed by solid-liquid separation in CS-101 to obtain the extract. The process steps and parameters of Step 2 and the combined addition are the same as in Example 1. Due to the lack of N2 gas nuclei to enhance the cavitation mechanical effect, the release efficiency of α-acids and linalool from the hop glands is significantly reduced, resulting in a significant deficiency of α-acids and linalool in the extract.

[0039] In this example, it is not possible to simultaneously achieve an α-acid isomerization rate ≥70% (specifically 54.6% in this example) and a linalool system utilization rate ≥45% (specifically 30.9% in this example) within 30 minutes.

[0040] Comparative Example 2 The difference between this example and Example 1 is that: (1) Step 2 is pure water cavitation isomerization without CO2 gas assistance, that is, CO2 gas is not injected during cavitation isomerization treatment, and the remaining steps and parameters are the same as in Example 1.

[0041] The specific process steps and parameters of the above preparation process include: The process steps and parameters for Step 1 and the combined addition are the same as in Example 1; Step 2 (pure water cavitation isomerization, without CO2 gas assistance): The extract and hot wort taken from the main boiling kettle are mixed in V-102 at a weight ratio of 1:4 to form a carrier system, the pH is adjusted to 7.2 with KOH, and MgCl2 is added to make Mg 2+ The concentration reached 240 ppm. P-104 was activated, and the mixture was sequentially passed through HX-102 (maintained at 98°C) and CV-102 in a closed-loop system for 20 minutes, without any CO2 gas injection. Due to the lack of CO2 microbubbles as cavitation nuclei, the cavitation threshold increased, the bubble frequency decreased, and the peak bubble collapse temperature remained at a high level of approximately 1500 K, leading to the thermal degradation of some of the already generated iso-α-acids. Simultaneously, the lack of CO2 to replace dissolved oxygen in the system caused oxidative degradation of both α-acids and iso-α-acids.

[0042] In this example, it is not possible to simultaneously achieve an α-acid isomerization rate ≥70% (specifically 57.3% in this example) and a linalool system utilization rate ≥45% (specifically 39.4% in this example) within 30 minutes.

[0043] Comparative Example 3 The difference between this example and Example 1 is that: (1) Step 2 is cavitation isomerization without pH engineering adjustment, that is, KOH is not used to adjust the pH of the carrier system during cavitation isomerization treatment, and the system maintains the natural pH of the wort (about 5.2~5.4). The remaining steps and parameters are the same as in Example 1.

[0044] The specific process steps and parameters of the above preparation process include: The process steps and parameters for step one and the combined addition are the same as in Example 1; in step two, KOH is not used to adjust the pH of the carrier system, and the system maintains the natural pH of the wort (approximately 5.2~5.4). The remaining process steps and parameters (98°C, Mg) are the same. 2+The concentration (240 ppm), CO2 gas-liquid ratio (2%), and closed-loop treatment for 20 minutes were the same as in Example 1. Due to the significantly reduced α-acid ionization at low pH, the isomerization rate k1 decreased by approximately 6.25 times compared to pH 7.2, and the isomerization reaction was far from complete within 30 minutes.

[0045] In this example, it is not possible to simultaneously achieve an α-acid isomerization rate ≥70% (specifically 32.5% in this example) and a linalool system utilization rate ≥45% (specifically 50.8% in this example) within 30 minutes.

[0046] Comparative Example 4 The difference between this example and Example 1 is that: (1) Step 2 is cavitation isomerization without divalent metal ion catalyst, that is, MgCl2 is not added during cavitation isomerization treatment, and the remaining steps and parameters are the same as in Example 1.

[0047] The specific process steps and parameters of the above preparation process include: The process steps and parameters for step one and the combined addition are the same as in Example 1; MgCl2 is not added in step two (there is no Mg in the current-carrying system). 2+ The catalyst was a divalent metal ion (98°C, pH 7.2, CO2 gas-liquid ratio 2%, closed-loop treatment for 20 minutes). All other process steps and parameters were the same as in Example 1. Due to the lack of Mg... 2+ The catalytic effect of coordination between Lewis acid and α-acid enol salt to form a five-membered chelate ring maintained the isomerization activation energy at a relatively high level of about 98.6 kJ / mol, and the isomerization rate k1 decreased by 1.5 to 2.0 times compared with Example 1.

[0048] In this example, it is not possible to simultaneously achieve an α-acid isomerization rate ≥70% (specifically 60.2% in this example) and a linalool system utilization rate ≥45% (specifically 51.0% in this example) within 30 minutes.

[0049] Comparative Example 5 The difference between this example and Example 1 is that: (1) Step 2 is an open (non-closed) system cavitation isomerization, that is, the isomerization reaction vessel V-102 is not set with a back pressure of 0.2~0.5 bar and is directly opened to the atmosphere for exhaust. The remaining steps and parameters are the same as in Example 1.

[0050] The specific process steps and parameters of the above preparation process include: The process steps and parameters for Step 1 and the combined addition are the same as in Example 1; in Step 2, the isomerization reactor V-102 is operated openly (without back pressure, non-closed circulation), and the remaining process steps and parameters (98°C, pH 7.2, Mg) are the same.2+ The concentration (240 ppm), CO2 gas-liquid ratio (2%), and treatment time (20 minutes) were the same as in Example 1. Because linalool in the open system was no longer limited by the closed-loop Henry equilibrium, a large amount was lost with water vapor at 98°C, resulting in a cumulative evaporation loss of over 80% within 30 minutes.

[0051] In this example, it is not possible to simultaneously achieve an α-acid isomerization rate of ≥70% (specifically 74.9% in this example) and a linalool system utilization rate of ≥45% (specifically 12.6% in this example) within 30 minutes.

[0052] Various embodiments of the present invention may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of the invention; therefore, it should be considered that the range description has specifically disclosed all possible subranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the range referred to.

[0053] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for treating hops using air-assisted hydraulic cavitation, characterized in that, Includes the following steps: After adding hops to water, an inert gas is injected to perform hydraulic cavitation extraction and solid-liquid separation to obtain the extract. The extract is mixed with a portion of hot wort taken from the boiling stage to form a carrier system, and then subjected to cavitation isomerization treatment under the action of divalent metal ion catalyst and carbon dioxide to obtain an isomerized liquid. The isomerized liquid is added back to the hot wort that is in the boiling stage to complete dilution, natural pH neutralization and residual isomerization.

2. The gas-assisted hydraulic cavitation hop treatment method according to claim 1, characterized in that, The operating conditions for the hydrocavitation extraction include: pH 7.6-8.0, temperature 80-95℃, and time 5-25 min. The operating conditions for the cavitation isomerization treatment include: pH 6.5-7.5, temperature 95-100℃, and time 20-40 min.

3. The gas-assisted hydraulic cavitation hop treatment method according to claim 1, characterized in that, During the hydrocavitation extraction process The weight ratio of the hops to the water is (1~2):(10~20), and the gas-liquid ratio of the system after the inert gas is injected is 2-5%.

4. The gas-assisted hydraulic cavitation hop treatment method according to claim 1, characterized in that, During the cavitation isomerization process After the carbon dioxide is injected, the gas-liquid ratio of the system is 1-3%, the weight ratio of the extract to the hot wort is (1-2):(2-10), and the concentration of the divalent metal ion catalyst in the system is 100-300 ppm.

5. The gas-assisted hydraulic cavitation hop treatment method according to claim 1, characterized in that, The inert gas includes at least one of nitrogen and argon, and the hops include at least one of T90 particles, T45 particles, and CO2 hop extract; The divalent metal ion catalyst includes at least one of magnesium ions, calcium ions, and zinc ions.

6. The gas-assisted hydraulic cavitation hop treatment method according to any one of claims 1-5, characterized in that, It can simultaneously achieve an α-acid isomerization rate of ≥70% and a linalool system utilization rate of ≥45% within 30 minutes.

7. A gas-assisted hydraulic cavitation hop treatment device, characterized in that, The method for treating hops using air-assisted hydraulic cavitation as described in any one of claims 1 to 6 includes: Mother liquor tank, used to prepare and contain alkalization extraction mother liquor; The first circulation loop includes a first circulation pump and a first hydraulic cavitation device. The first hydraulic cavitation device is provided with an inert gas injection port, and the loop returns to the mother liquor tank. A solid-liquid separator is connected to the first circulation loop and outputs a solid-free extract. The isomerization reaction vessel is sealed and equipped with back pressure exhaust, and is connected to the main boiling pot via insulated pipeline. The second circulation loop includes a second circulation pump, a heat exchanger and a second hydraulic cavitation device. The second hydraulic cavitation device is equipped with a CO2 gas injection port. The loop returns to the isomerization reaction tank. The feeding system adds pH adjuster and divalent metal ion catalyst to the mother liquor tank and the isomerization reaction tank, respectively. The control system is connected to sensors and actuators for temperature, pH, flow rate, and gas injection volume.

8. The gas-assisted hydraulic cavitation hop treatment device according to claim 7, characterized in that, The first hydraulic cavitation device and the second hydraulic cavitation device each independently include a Venturi-type hydraulic cavitation device, wherein the throat area ratio of the Venturi-type hydraulic cavitation device is 9%-12%; the gas is self-drawn in by the negative pressure of the throat, without additional pressurization equipment.

9. The gas-assisted hydraulic cavitation hop treatment device according to claim 7, characterized in that, It also includes a gas recirculation system that recovers the exhaust gas from the isomerization reactor and sends it back to the injection port of the second cavitation unit.

10. A beer brewing system, characterized in that, It includes a mash tun, a boiling tun, and the air-assisted hydraulic cavitation hop treatment device as described in any one of claims 7-9, wherein the air-assisted hydraulic cavitation hop treatment device is installed as a side-flow module between the mash tun and the boiling tun in the beer brewing process.

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