Method for improving wine brewing quality by using coffee

Abstract

The invention discloses a method for improving wine brewing quality by using coffee, and relates to the technical field of food processing.The method comprises the steps of coffee residue pretreatment, active substance extraction, wine brewing raw material treatment, compound fermentation and distillation and ageing. The coffee grounds which are originally treated as waste materials are converted into high-purity active ingredient carriers, and flavor synergistic factors in the high-purity active ingredient carriers are recycled; coffee active substances with different boiling points are separated through a fractional extraction technology, bitter taste interference caused by direct mixing in a traditional process is avoided, a layered coffee aroma base is formed in a wine body, and flavor coordination is improved; a staged adding and temperature joint control strategy is adopted, and a time window of coffee active ingredient release and saccharomyces cerevisiae metabolism is matched, so that caffeine continuously plays a flavor catalysis role in the key stage of fermentation; by establishing a dynamic mapping relation between the volatility of the coffee oil and fat and the distillation parameters, the problem of batch quality fluctuation is solved.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, and in particular to a method for improving the quality of brewing using coffee. Background Technology

[0002] Coffee, as one of the world's three major beverages, is highly favored by the Chinese market and consumers. It originated in Ethiopia and Congo in Africa and is mainly grown in tropical regions between 20 degrees north and south latitude. Winemaking is the process of producing alcoholic beverages with a certain concentration through microbial fermentation. The microorganisms used and the brewing process vary depending on the raw materials used in winemaking.

[0003] In existing brewing processes, to improve the flavor and quality of the liquor, the common methods are to adjust the ratio of raw materials, optimize fermentation parameters, and add natural flavorings. However, these methods have drawbacks: a large amount of coffee grounds produced during coffee processing are usually treated as waste, which neither effectively recovers the active ingredients nor prevents environmental pollution; directly adding coffee powder or simple extracts can lead to bitterness and mixed aromas in the liquor, and due to the lack of targeted separation and metering control of active coffee substances, it is impossible to achieve precise synergy of flavor factors; coffee components added in conventional processes are easily interfered with by microbial metabolism during fermentation, resulting in a high degradation rate of target flavor substances, and the volatility difference of coffee oils during the distillation stage will further amplify flavor fluctuations.

[0004] Therefore, a method for improving brewing quality using coffee is proposed to solve the above problems. Summary of the Invention

[0005] The main objective of this invention is to provide a method for improving the quality of brewing using coffee, in order to solve the problems mentioned in the background above.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a method for improving the quality of brewing using coffee, comprising the following steps:

[0007] Step 1: Coffee grounds pretreatment: Collect the coffee grounds generated during coffee processing, remove impurities by screening, rinse with a washing device, and then place them in a drying device to dry at 65±2℃ until the moisture content is ≤8%;

[0008] Step 2, Active substance extraction: The pretreated coffee grounds are put into a supercritical CO2 extraction device, the extraction pressure is set to 28-32 MPa and the temperature to 40-45℃, and the extraction is continued for 2.5-3.5 hours to separate caffeine extract and coffee oil extract.

[0009] Step 3: Processing of brewing raw materials: Crush the main brewing raw materials to 40-60 mesh, add 1.2-1.8 times the total weight of the raw materials in water, and cook and gelatinize them.

[0010] Step 4, Compound Fermentation: Inoculate the gelatinized mash with brewing yeast, and simultaneously add the caffeine extract and coffee oil extract obtained in Step 2. The amount added is 0.15-0.45% of the total weight of the brewing raw materials, and ferment at 22-28℃ for 8-12 days.

[0011] Step 5, Distillation and Aging: Transfer the fermentation liquid to a distillation apparatus, collect the spirit with an alcohol content of 50-65% vol in segments, and transfer it to oak barrels to age at 15-18℃ for more than 6 months.

[0012] Preferably, the coffee grounds pretreatment in step one includes:

[0013] Impurity removal: A vibrating screener at a speed of 100-150 r / min is used to remove solid impurities with a particle size >2 mm;

[0014] Gradient cleaning: First, rinse twice with soft water of pH 6.5-7.0, each time with a water volume of 3 times the weight of the coffee grounds, and then soak in 0.1% citric acid solution for 20 minutes;

[0015] Microwave-assisted drying: Apply 2450MHz microwaves with a power density of 0.8~1.2W / g to the drying equipment, and simultaneously blow in 40℃ hot air.

[0016] Preferably, in step two, the supercritical CO2 extraction employs a three-stage separation process, with the CO2 flow rate controlled at 12... 15 L / min, with a separation time of 45 seconds per stage. 60 minutes:

[0017] The primary separator operates at a pressure of 10–12 MPa and a temperature of 35°C, collecting coffee oils.

[0018] The secondary separator operates at a pressure of 6–8 MPa and a temperature of 30°C to collect caffeine.

[0019] The three-stage separator operates at a pressure of 4–5 MPa and a temperature of 25°C to recover residual solvent.

[0020] Preferably, the mass ratio of caffeine extract to coffee oil extract is 1.2 to 1.5:1, and the caffeine purity is ≥95% and the unsaturated fatty acid content in the coffee oil is ≥78%.

[0021] Preferably, the compound fermentation in step four includes:

[0022] Yeast activation: Add Angel brewing high-activity dry yeast to a 35℃ sucrose solution at a ratio of 1:10 and activate for 30 minutes;

[0023] Add in stages: Add 70% of the total coffee extract 3 days before fermentation, and add the remaining 30% on the 4th day;

[0024] Dynamic temperature control: maintain 25±0.5℃ for the first 72 hours, and then increase to 28±0.5℃ in the later stage.

[0025] Preferably, the main raw materials for brewing are at least two of sorghum, rice, and wheat, with a ratio range of 40-60% sorghum, 20-35% rice, and 15-25% wheat, and the particle size D90 value of the raw materials is controlled at 150-200 μm.

[0026] Preferably, step five, distillation, employs a variable-temperature distillation process.

[0027] Initial distillation section: steam temperature 78-82℃, heads collected: accounting for 5% of the total volume;

[0028] Middle section: Steam temperature 82-90℃, main liquor collected: accounting for 80% of the total volume;

[0029] Tail section: Steam temperature 90-95℃, collected tails: accounting for 15% of the total.

[0030] Preferably, the aging process includes:

[0031] Oak barrel pretreatment: Use moderately toasted American white oak barrels with a wall thickness of 22±1mm;

[0032] Micro-oxygen control: The dissolved oxygen concentration in the tank is monitored in real time by a dissolved oxygen sensor and controlled at 1.5. Within the range of 2.0 mg / L;

[0033] Antioxidant treatment: Add 50% antioxidants during the early stages of aging. 100 mg / L of food-grade vitamin E as an antioxidant;

[0034] Periodic stirring: Stir at 10 r / min for 5 minutes every 30 days.

[0035] Preferably, the wine prepared by the method contains:

[0036] Caffeine content: 8–15 mg / L;

[0037] Chlorogenic acid derivative content: 12-20 mg / L;

[0038] The reduction rate of higher alcohol content is ≥35%;

[0039] Sensory rating improved by ≥15%.

[0040] Preferably, it also includes a quality control system:

[0041] Raw material activity monitoring: After extraction in step two, high performance liquid chromatography was immediately used to detect the purity of caffeine extract and the proportion of unsaturated fatty acids in coffee oil. The control indicators were caffeine purity ≥95% and unsaturated fatty acids ≥78%.

[0042] Fermentation kinetics control: Samples were taken on day 5 of fermentation, and the formation rates of ethyl acetate and ethyl lactate in the mash were analyzed by gas chromatography-mass spectrometry. When the ratio of ethyl acetate to ethyl lactate exceeded the range of 1.2 to 1.8, the coffee extract replenishment program was automatically triggered.

[0043] Flavor stability assurance: Samples are taken every 60 days during the aging process, and gas chromatography-olfactometry analysis is performed to monitor the intensity decay rate of characteristic coffee aroma components: 2-ethylfuran and furfuryl mercaptan. When the decay rate is >15% / 60 days, the micro-oxygen supply rate of the oak barrel is adjusted to 10-15 mL / min·m³.

[0044] The present invention has the following beneficial effects:

[0045] 1. In this invention, by establishing a targeted treatment system for coffee waste, coffee grounds that were originally treated as waste are transformed into carriers of high-purity active ingredients, and flavor-enhancing factors are recovered. The invention innovatively separates coffee active substances with different boiling points through graded extraction technology, and establishes a synergistic metabolic pathway with brewing microorganisms during the fermentation stage. This avoids the interference of bitterness caused by direct mixing in traditional processes, and promotes the formation of a layered coffee aroma base in the wine, thereby improving the flavor harmony.

[0046] 2. In this invention, a segmented addition and temperature control strategy is adopted to match the time window of coffee active ingredient release and brewing yeast metabolism, so that caffeine can continue to play a flavor catalytic role in the key stage of fermentation; by establishing a dynamic mapping relationship between coffee oil volatility and distillation parameters, the difference in flavor substance escape caused by temperature gradient is automatically compensated in the distillation process, ensuring the stable expression of coffee characteristic flavor in the liquor and overcoming the problem of batch quality fluctuation.

[0047] 3. In this invention, the detection of active coffee components, the kinetic analysis of ester formation, and the monitoring of the volatility of flavor substances are innovatively integrated into a full-process quality control system, realizing multi-node quality intervention from raw material processing to the end of aging; through real-time correlation analysis of key indicators of fermentation liquid and coffee additive factors, the combination of process parameters is automatically optimized, which not only controls the formation rate of target flavor substances, but also inhibits the accumulation of undesirable metabolites, and improves the sensory purity and flavor persistence of the wine. Detailed Implementation

[0048] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0049] Example 1: A method for improving brewing quality using coffee, comprising the following steps:

[0050] Step 1: Coffee grounds pretreatment: Collect the coffee grounds generated during coffee processing, remove impurities by screening, rinse with a washing device, and then place them in a drying device to dry at 63℃ until the moisture content is ≤8%;

[0051] Step 2, Active substance extraction: The pretreated coffee grounds are put into a supercritical CO2 extraction device, the extraction pressure is set to 28MPa and the temperature to 40℃, and the extraction is continued for 2.5 hours to separate caffeine extract and coffee oil extract.

[0052] Step 3, processing of brewing raw materials: crush the main brewing raw materials to 40 mesh, add water with 1.2 times the total weight of the raw materials and cook and gelatinize them;

[0053] Step 4, Compound Fermentation: Inoculate the gelatinized mash with brewing yeast, and add the caffeine extract and coffee oil extract obtained in Step 2 at a rate of 0.15% of the total weight of the brewing raw materials. Ferment at 22°C for 8 days.

[0054] Step 5, Distillation and Aging: Transfer the fermentation liquid to a distillation apparatus, collect the spirit with an alcohol content of 50% vol in segments, and transfer it to oak barrels to age at 15°C for more than 6 months.

[0055] Step one, coffee grounds pretreatment, includes:

[0056] Impurity removal: A vibrating screener at a speed of 100 r / min is used to remove solid impurities with a particle size >2 mm;

[0057] Gradient cleaning: First, rinse twice with soft water of pH 6.5, each time with a water volume of 3 times the weight of the coffee grounds, and then soak in 0.1% citric acid solution for 20 minutes;

[0058] Microwave-assisted drying: Apply 2450MHz microwaves with a power density of 0.8W / g to the drying equipment, and simultaneously blow in 40℃ hot air.

[0059] In step two, the supercritical CO2 extraction employs a three-stage separation process, with the CO2 flow rate controlled at 12 L / min and each stage lasting 45 minutes.

[0060] The primary separator operates at a pressure of 10 MPa and a temperature of 35°C to collect coffee oils.

[0061] The secondary separator operates at a pressure of 6 MPa and a temperature of 30°C to collect caffeine.

[0062] The three-stage separator operates at a pressure of 4 MPa and a temperature of 25 °C to recover residual solvent.

[0063] The mass ratio of caffeine extract to coffee oil extract is 1.2:1, and the caffeine purity is ≥95% and the unsaturated fatty acid content in coffee oil is ≥78%.

[0064] Step four, the compound fermentation, includes:

[0065] Yeast activation: Add Angel brewing high-activity dry yeast to a 35℃ sucrose solution at a ratio of 1:10 and activate for 30 minutes;

[0066] Add in stages: Add 70% of the total coffee extract 3 days before fermentation, and add the remaining 30% on the 4th day;

[0067] Dynamic temperature control: maintain 25±0.5℃ for the first 72 hours, and then increase to 28±0.5℃ in the later stage.

[0068] The main raw materials for brewing are at least two of sorghum, rice and wheat, with a ratio range of 40% sorghum, 20% rice and 15% wheat, and the particle size D90 value of the raw materials is controlled at 150μm.

[0069] Step 5, distillation, employs a variable-temperature distillation process:

[0070] Initial distillation section: steam temperature 78℃, heads collected: 5% of total volume;

[0071] Middle section: Steam temperature 82℃, main liquor collected: accounting for 80% of the total volume;

[0072] Tail section: Steam temperature 90℃, collected tails: accounting for 15% of the total.

[0073] The aging process includes:

[0074] Oak barrel pretreatment: Uses moderately toasted American white oak barrels with a wall thickness of 21mm;

[0075] Micro-oxygen control: The dissolved oxygen concentration in the tank is monitored in real time by a dissolved oxygen sensor and controlled at 1.5 mg / L;

[0076] Antioxidant treatment: 50 mg / L of food-grade vitamin E is added as an antioxidant during the early stages of aging;

[0077] Periodic stirring: Stir at 10 r / min for 5 minutes every 30 days.

[0078] In the wine prepared by this method:

[0079] Caffeine content: 8 mg / L;

[0080] Chlorogenic acid derivative content: 12 mg / L;

[0081] The reduction rate of higher alcohol content is ≥35%;

[0082] Sensory rating improved by ≥15%.

[0083] It also includes a quality control system:

[0084] Raw material activity monitoring: After extraction in step two, high performance liquid chromatography was immediately used to detect the purity of caffeine extract and the proportion of unsaturated fatty acids in coffee oil. The control indicators were caffeine purity ≥95% and unsaturated fatty acids ≥78%.

[0085] Fermentation kinetics control: Samples were taken on day 5 of fermentation, and the formation rates of ethyl acetate and ethyl lactate in the mash were analyzed by gas chromatography-mass spectrometry. When the ratio of ethyl acetate to ethyl lactate exceeded the range of 1.2 to 1.8, the coffee extract replenishment program was automatically triggered.

[0086] Flavor stability assurance: Samples are taken every 60 days during the aging process, and gas chromatography-olfactometry analysis is performed to monitor the intensity decay rate of characteristic coffee aroma components: 2-ethylfuran and furfuryl mercaptan. When the decay rate is >15% / 60 days, the micro-oxygen supply rate of the oak barrel is adjusted to 10-15 mL / min·m³.

[0087] Example 2: A method for improving brewing quality using coffee, comprising the following steps:

[0088] Step 1: Coffee grounds pretreatment: Collect the coffee grounds generated during coffee processing, remove impurities by screening, rinse with a washing device, and then place them in a drying device to dry at 65℃ until the moisture content is ≤8%;

[0089] Step 2, Active substance extraction: The pretreated coffee grounds are put into a supercritical CO2 extraction device, the extraction pressure is set to 30MPa and the temperature to 43℃, and the extraction is continued for 3.0 hours to separate caffeine extract and coffee oil extract.

[0090] Step 3: Processing of brewing raw materials: Crush the main brewing raw materials to 50 mesh, add water with a total weight of 1.5 times the weight of the raw materials, and cook and gelatinize them;

[0091] Step 4, Compound Fermentation: Inoculate the gelatinized mash with brewing yeast, and add the caffeine extract and coffee oil extract obtained in Step 2 at a rate of 0.30% of the total weight of the brewing raw materials. Ferment at 25°C for 10 days.

[0092] Step 5, Distillation and Aging: Transfer the fermentation liquid to a distillation apparatus, collect the spirit with an alcohol content of 58% vol in segments, and transfer it to oak barrels to age at 17°C for more than 6 months.

[0093] Step one, coffee grounds pretreatment, includes:

[0094] Impurity removal: A vibrating screener at a speed of 125 r / min is used to remove solid impurities with a particle size >2 mm;

[0095] Gradient cleaning: First, rinse twice with soft water at pH 6.8, each time using three times the weight of the coffee grounds. Then, soak in a 0.1% citric acid solution for 20 minutes.

[0096] Microwave-assisted drying: Apply 2450MHz microwaves with a power density of 1.0W / g to the drying equipment, and simultaneously blow in 40℃ hot air.

[0097] In step two, the supercritical CO2 extraction employs a three-stage separation process, with the CO2 flow rate controlled at 13.5 L / min and each stage lasting 53 minutes.

[0098] The primary separator operates at a pressure of 11 MPa and a temperature of 35°C, collecting coffee oils.

[0099] The secondary separator operates at a pressure of 7 MPa and a temperature of 30°C to collect caffeine.

[0100] The three-stage separator operates at a pressure of 4.5 MPa and a temperature of 25 °C to recover residual solvent.

[0101] The mass ratio of caffeine extract to coffee oil extract is 1.4:1, and the caffeine purity is ≥95% and the unsaturated fatty acid content in coffee oil is ≥78%.

[0102] Step four, the compound fermentation, includes:

[0103] Yeast activation: Add Angel brewing high-activity dry yeast to a 35℃ sucrose solution at a ratio of 1:10 and activate for 30 minutes;

[0104] Add in stages: Add 70% of the total coffee extract 3 days before fermentation, and add the remaining 30% on the 4th day;

[0105] Dynamic temperature control: Maintain 25℃ for the first 72 hours, then increase to 28℃.

[0106] The main raw materials for brewing are at least two of sorghum, rice, and wheat, with a ratio range of 50% sorghum, 28% rice, and 20% wheat, and the particle size D90 value of the raw materials is controlled at 175μm.

[0107] Step 5, distillation, employs a variable-temperature distillation process:

[0108] Initial distillation section: steam temperature 80℃, heads collected: 5% of total volume;

[0109] Middle section: Steam temperature 86℃, main liquor collected: accounting for 80% of the total volume;

[0110] Tail section: Steam temperature 93℃, collected tails: accounting for 15% of the total.

[0111] The aging process includes:

[0112] Oak barrel pretreatment: Uses moderately toasted American white oak barrels with a wall thickness of 22mm;

[0113] Micro-oxygen control: The dissolved oxygen concentration in the tank is monitored in real time by a dissolved oxygen sensor and controlled at 1.75 mg / L;

[0114] Antioxidant treatment: 85 mg / L of food-grade vitamin E is added as an antioxidant during the early stages of aging;

[0115] Periodic stirring: Stir at 10 r / min for 5 minutes every 30 days.

[0116] In the wine prepared by this method:

[0117] Caffeine content: 12 mg / L;

[0118] Chlorogenic acid derivative content: 16 mg / L;

[0119] The reduction rate of higher alcohol content is ≥35%;

[0120] Sensory rating improved by ≥15%.

[0121] It also includes a quality control system:

[0122] Raw material activity monitoring: After extraction in step two, high performance liquid chromatography was immediately used to detect the purity of caffeine extract and the proportion of unsaturated fatty acids in coffee oil. The control indicators were caffeine purity ≥95% and unsaturated fatty acids ≥78%.

[0123] Fermentation kinetics control: Samples were taken on day 5 of fermentation, and the formation rates of ethyl acetate and ethyl lactate in the mash were analyzed by gas chromatography-mass spectrometry. When the ratio of ethyl acetate to ethyl lactate exceeded the range of 1.2 to 1.8, the coffee extract replenishment program was automatically triggered.

[0124] Flavor stability assurance: Samples are taken every 60 days during the aging process, and gas chromatography-olfactometry analysis is performed to monitor the intensity decay rate of characteristic coffee aroma components: 2-ethylfuran and furfuryl mercaptan. When the decay rate is >15% / 60 days, the micro-oxygen supply rate of the oak barrel is adjusted to 10-15 mL / min·m³.

[0125] Example 3: A method for improving brewing quality using coffee, comprising the following steps:

[0126] Step 1: Coffee grounds pretreatment: Collect the coffee grounds generated during coffee processing, remove impurities by screening, rinse with a washing device, and then place them in a drying device to dry at 67°C until the moisture content is ≤8%;

[0127] Step 2, Active substance extraction: The pretreated coffee grounds are put into a supercritical CO2 extraction device, the extraction pressure is set to 32MPa and the temperature to 45℃, and the extraction is continued for 3.5 hours to separate caffeine extract and coffee oil extract.

[0128] Step 3, processing of brewing raw materials: crush the main brewing raw materials to 60 mesh, add water with a total weight of 1.8 times the weight of the raw materials and cook and gelatinize them;

[0129] Step 4, Compound Fermentation: Inoculate the gelatinized mash with brewing yeast, and add the caffeine extract and coffee oil extract obtained in Step 2 at a rate of 0.45% of the total weight of the brewing raw materials. Ferment at 28°C for 12 days.

[0130] Step 5, Distillation and Aging: Transfer the fermentation liquid to a distillation apparatus, collect the spirit with an alcohol content of 65% vol in segments, and transfer it to oak barrels to age at 18°C ​​for more than 6 months.

[0131] Step one, coffee grounds pretreatment, includes:

[0132] Impurity removal: A vibrating screener at a speed of 150 r / min is used to remove solid impurities with a particle size >2 mm;

[0133] Gradient cleaning: First, rinse twice with soft water of pH 7.0, each time with a water volume of 3 times the weight of the coffee grounds, and then soak in 0.1% citric acid solution for 20 minutes;

[0134] Microwave-assisted drying: Apply 2450MHz microwaves with a power density of 1.2W / g to the drying equipment, and simultaneously blow in 40℃ hot air.

[0135] In step two, the supercritical CO2 extraction employs a three-stage separation process, with the CO2 flow rate controlled at 15 L / min and each stage lasting 60 minutes.

[0136] The primary separator operates at a pressure of 12 MPa and a temperature of 35°C, collecting coffee oils.

[0137] The secondary separator operates at a pressure of 8 MPa and a temperature of 30°C to collect caffeine.

[0138] The three-stage separator operates at a pressure of 5 MPa and a temperature of 25 °C to recover residual solvent.

[0139] The mass ratio of caffeine extract to coffee oil extract is 1.5:1, and the caffeine purity is ≥95% and the unsaturated fatty acid content in coffee oil is ≥78%.

[0140] Step four, the compound fermentation, includes:

[0141] Yeast activation: Add Angel brewing high-activity dry yeast to a 35℃ sucrose solution at a ratio of 1:10 and activate for 30 minutes;

[0142] Add in stages: Add 70% of the total coffee extract 3 days before fermentation, and add the remaining 30% on the 4th day;

[0143] Dynamic temperature control: maintain 25±0.5℃ for the first 72 hours, and then increase to 28±0.5℃ in the later stage.

[0144] The main raw materials for brewing are at least two of sorghum, rice and wheat, with a ratio range of 60% sorghum, 35% rice and 15% wheat, and the particle size D90 value of the raw materials is controlled at 200μm.

[0145] Step 5, distillation, employs a variable-temperature distillation process:

[0146] Initial distillation section: steam temperature 82℃, heads collected: 5% of total volume;

[0147] Middle section: Steam temperature 90℃, main liquor collected: accounting for 80% of the total volume;

[0148] Tail section: Steam temperature 95℃, collected tails: accounting for 15% of the total.

[0149] The aging process includes:

[0150] Oak barrel pretreatment: Uses moderately toasted American white oak barrels with a wall thickness of 23mm;

[0151] Micro-oxygen control: The dissolved oxygen concentration in the tank is monitored in real time by a dissolved oxygen sensor and controlled at 2.0 mg / L;

[0152] Antioxidant treatment: 100 mg / L of food-grade vitamin E is added as an antioxidant during the early stages of aging;

[0153] Periodic stirring: Stir at 10 r / min for 5 minutes every 30 days.

[0154] In the wine prepared by this method:

[0155] Caffeine content: 15mg / L;

[0156] Chlorogenic acid derivative content: 20 mg / L;

[0157] The reduction rate of higher alcohol content is ≥35%;

[0158] Sensory rating improved by ≥15%.

[0159] It also includes a quality control system:

[0160] Raw material activity monitoring: After extraction in step two, high performance liquid chromatography was immediately used to detect the purity of caffeine extract and the proportion of unsaturated fatty acids in coffee oil. The control indicators were caffeine purity ≥95% and unsaturated fatty acids ≥78%.

[0161] Fermentation kinetics control: Samples were taken on day 5 of fermentation, and the formation rates of ethyl acetate and ethyl lactate in the mash were analyzed by gas chromatography-mass spectrometry. When the ratio of ethyl acetate to ethyl lactate exceeded the range of 1.2 to 1.8, the coffee extract replenishment program was automatically triggered.

[0162] Flavor stability assurance: Samples are taken every 60 days during the aging process, and gas chromatography-olfactometry analysis is performed to monitor the intensity decay rate of characteristic coffee aroma components: 2-ethylfuran and furfuryl mercaptan. When the decay rate is >15% / 60 days, the micro-oxygen supply rate of the oak barrel is adjusted to 10-15 mL / min·m³.

[0163] Comparative Example 1: The difference between this comparative example and Example 1 is that no coffee oil extract was added during the compound fermentation process in this comparative example.

[0164] Comparative Example 2 differs from Example 1 in that: in this comparative example, coffee extract was added in a single step during the fermentation stage; under the same conditions of raw materials, temperature, etc., only the method of adding coffee extract was changed, which increased the content of higher alcohols from 52.3 mg / L to 70.2 mg / L; this directly proves that the segmented addition strategy is the key independent factor in inhibiting the formation of higher alcohols, rather than other variables such as temperature fluctuations. Its mechanism of action is achieved by optimizing the yeast metabolic environment and reducing the abnormal degradation of branched-chain amino acids.

[0165] Comparative Example 3 differs from Example 1 in that conventional ethanol extraction is used instead of supercritical CO2 extraction in this comparative example.

[0166] Comparative Example 4 differs from Example 1 in that micro-oxygen control is disabled during the aging stage in this comparative example.

[0167] The performance of the wines produced in Examples 1-3 and Comparative Examples 1-4 was tested. The test items and methods are as follows:

[0168] Flavor compound retention rate: The difference in caffeine and chlorogenic acid derivative content before and after fermentation was detected by HPLC, and the retention rate was calculated.

[0169] Higher alcohol content: The total amount of isobutanol and isoamyl alcohol was determined by gas chromatography;

[0170] Sensory harmony: Blind evaluation by certified sommeliers based on indicators such as aroma purity and taste balance;

[0171] Batch stability: After continuous production of multiple batches, the coefficient of variation of the concentration of the main flavor compounds was tested.

[0172] The test data of the wines prepared in Examples 1-3 and Comparative Examples 1-4 are recorded in the table below:

[0173] Group Flavor compound retention rate (%) Higher alcohol content (mg / L) Sensory coordination (points) Batch stability (coefficient of variation) Example 1 94.8% 52.3 92 3.8% Example 2 93.5% 55.1 89 4.2% Example 3 90.7% 61.4 87 7.5% Comparative Example 1 76.2% 89.6 73 14.9% Comparative Example 2 68.4% 70.2 71 12.3% Comparative Example 3 82.1% 85.7 69 18.6% Comparative Example 4 88.9% 56.3 75 22.4%

[0174] By comparing and analyzing the data in the table, it can be seen that the wine prepared using the processes in Examples 1-3 has significantly better performance than the wine prepared using the processes in Comparative Examples 1-4. This indicates that this method, by establishing a targeted treatment system for coffee waste, transforms coffee grounds, which were originally treated as waste, into a high-purity carrier of active ingredients and recovers the flavor-enhancing factors. It innovatively separates coffee active substances with different boiling points using graded extraction technology, establishing a synergistic metabolic pathway with brewing microorganisms during the fermentation stage. This avoids the bitterness interference caused by direct mixing in traditional processes and promotes the formation of a layered coffee aroma base in the wine, improving flavor harmony. This method employs... A segmented addition strategy combined with temperature control, matching the time window for the release of active coffee components and the metabolism of brewer's yeast, allows caffeine to continuously exert its flavor catalytic effect during key fermentation stages. Caffeine not only acts as a flavor compound during fermentation but also plays a biocatalytic role. Real-time quantitative PCR analysis revealed that in the experimental group with added caffeine extract, the expression levels of yeast alcohol acetyltransferase gene were upregulated by 2.1 ± 0.3 times, and the expression levels of fatty acid ethyl ester synthase gene were upregulated by 1.8 ± 0.2 times. This indicates that caffeine promotes the biosynthesis of flavor esters such as ethyl acetate and ethyl hexanoate by regulating the gene expression of key yeast metabolic enzymes. Simultaneously, caffeine... Caffeine inhibited the activity of branched-chain amino acid transaminases, reducing the production of higher alcohols such as isoamyl alcohol by more than 35%. This bidirectional regulatory effect on yeast metabolic pathways confirms the flavor catalytic function of caffeine. This method establishes a dynamic mapping relationship between the volatility of coffee oils and distillation parameters, specifically by using online gas chromatography to detect the concentration changes of characteristic coffee aroma components in the distillate every 5 minutes. When the peak concentration of furfuryl mercaptan is detected to appear prematurely, the steam pressure is automatically reduced by 0.05 MPa and the reflux ratio is increased by 15-20%. The steam temperature in the middle section is dynamically adjusted according to the unsaturated fatty acid content in the coffee oils: for every 5% increase in unsaturated fatty acids, the steam temperature is adjusted accordingly. The steam temperature is lowered by 1.5℃; the difference in flavor substance emission caused by temperature gradient during the distillation process is automatically compensated to ensure the stable expression of coffee characteristic flavor in the liquor and overcome batch quality fluctuation problems; this method innovatively integrates the detection of active coffee components, ester formation kinetic analysis, and flavor substance volatility monitoring into a whole-process quality control system, realizing multi-node quality intervention from raw material processing to the end of aging; through real-time correlation analysis of key indicators of fermentation liquid and coffee additive factors, the combination of process parameters is automatically optimized, which not only controls the formation rate of target flavor substances, but also inhibits the accumulation of undesirable metabolites, and improves the sensory purity and flavor persistence of the liquor.

[0175] By comparing and analyzing the relevant data in the table, it can be seen that the wine prepared by the molding process of this invention not only has outstanding flavor harmony and quality stability, but also demonstrates that the method of using coffee to improve winemaking quality provided by this invention has a broader market prospect and is more suitable for promotion.

[0176] The embodiments described herein are preferred embodiments and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be included within the scope of protection of this application.

Claims

1. A method for improving brewing quality using coffee, characterized in that: Includes the following steps: Step 1: Coffee grounds pretreatment: Collect the coffee grounds generated during coffee processing, remove impurities by screening, rinse with a washing device, and then place them in a drying device to dry at 65±2℃ until the moisture content is ≤8%; Step 2, Active substance extraction: The pretreated coffee grounds are put into a supercritical CO2 extraction device, the extraction pressure is set to 28-32 MPa and the temperature to 40-45℃, and the extraction is continued for 2.5-3.5 hours to separate caffeine extract and coffee oil extract. Step 3: Processing of brewing raw materials: Crush the main brewing raw materials to 40-60 mesh, add 1.2-1.8 times the total weight of the raw materials in water, and cook and gelatinize them. Step 4, Compound Fermentation: Inoculate the gelatinized mash with brewing yeast, and simultaneously add the caffeine extract and coffee oil extract obtained in Step 2. The amount added is 0.15-0.45% of the total weight of the brewing raw materials, and ferment at 22-28℃ for 8-12 days. Step 5, Distillation and Aging: Transfer the fermentation liquid to a distillation apparatus, collect the spirit with an alcohol content of 50-65% vol in segments, and transfer it to oak barrels to age at 15-18℃ for more than 6 months.

2. The method for improving brewing quality using coffee according to claim 1, characterized in that: The coffee grounds pretreatment in step one includes: Impurity removal: A vibrating screener at a speed of 100-150 r / min is used to remove solid impurities with a particle size >2 mm; Gradient cleaning: First, rinse twice with soft water of pH 6.5-7.0, each time with a water volume of 3 times the weight of the coffee grounds, and then soak in 0.1% citric acid solution for 20 minutes; Microwave-assisted drying: Apply 2450MHz microwaves with a power density of 0.8~1.2W / g to the drying equipment, and simultaneously blow in 40℃ hot air.

3. The method for improving brewing quality using coffee according to claim 1, characterized in that: In step two, the supercritical CO2 extraction employs a three-stage separation process, with the CO2 flow rate controlled at 12... 15 L / min, with a separation time of 45 seconds per stage. 60 minutes: The primary separator operates at a pressure of 10–12 MPa and a temperature of 35°C, collecting coffee oils. The secondary separator operates at a pressure of 6–8 MPa and a temperature of 30°C to collect caffeine. The three-stage separator operates at a pressure of 4–5 MPa and a temperature of 25°C to recover residual solvent.

4. The method for improving brewing quality using coffee according to claim 1, characterized in that: The mass ratio of caffeine extract to coffee oil extract is 1.2 to 1.5:1, and the caffeine purity is ≥95% and the unsaturated fatty acid content in the coffee oil is ≥78%.

5. The method for improving brewing quality using coffee according to claim 1, characterized in that: The compound fermentation in step four includes: Yeast activation: Add Angel brewing high-activity dry yeast to a 35℃ sucrose solution at a ratio of 1:10 and activate for 30 minutes; Add in stages: Add 70% of the total coffee extract 3 days before fermentation, and add the remaining 30% on the 4th day; Dynamic temperature control: maintain 25±0.5℃ for the first 72 hours, and then increase to 28±0.5℃ in the later stage.

6. The method for improving brewing quality using coffee according to claim 1, characterized in that: The main raw materials for brewing are at least two of sorghum, rice, and wheat, with a ratio range of 40-60% sorghum, 20-35% rice, and 15-25% wheat, and the particle size D90 value of the raw materials is controlled at 150-200μm.

7. The method for improving brewing quality using coffee according to claim 1, characterized in that: The distillation in step five employs a variable-temperature distillation process. Initial distillation section: steam temperature 78-82℃, heads collected: accounting for 5% of the total volume; Middle section: Steam temperature 82-90℃, main liquor collected: accounting for 80% of the total volume; Tail section: Steam temperature 90-95℃, collected tails: accounting for 15% of the total.

8. A method for improving brewing quality using coffee according to claim 1, characterized in that: The aging process includes: Oak barrel pretreatment: Use moderately toasted American white oak barrels with a wall thickness of 22±1mm; Micro-oxygen control: The dissolved oxygen concentration in the tank is monitored in real time by a dissolved oxygen sensor and controlled at 1.

5. Within the range of 2.0 mg / L; Antioxidant treatment: Add 50% antioxidants during the early stages of aging. 100 mg / L of food-grade vitamin E as an antioxidant; Periodic stirring: Stir at 10 r / min for 5 minutes every 30 days.

9. A method for improving brewing quality using coffee according to claim 1, characterized in that: The wine prepared by the method contains: Caffeine content: 8–15 mg / L; Chlorogenic acid derivative content: 12-20 mg / L; The reduction rate of higher alcohol content is ≥35%; Sensory rating improved by ≥15%.

10. A method for improving brewing quality using coffee according to claim 1, characterized in that: It also includes a quality control system: Raw material activity monitoring: After extraction in step two, high performance liquid chromatography was immediately used to detect the purity of caffeine extract and the proportion of unsaturated fatty acids in coffee oil. The control indicators were caffeine purity ≥95% and unsaturated fatty acids ≥78%. Fermentation kinetics control: Samples were taken on day 5 of fermentation, and the formation rates of ethyl acetate and ethyl lactate in the mash were analyzed by gas chromatography-mass spectrometry. When the ratio of ethyl acetate to ethyl lactate exceeded the range of 1.2 to 1.8, the coffee extract replenishment program was automatically triggered. Flavor stability assurance: Samples are taken every 60 days during the aging process, and gas chromatography-olfactometry analysis is performed to monitor the intensity decay rate of coffee characteristic aroma components: 2-ethylfuran and furfuryl mercaptan. When the decay rate is >15% / 60 days, the micro-oxygen supply rate of the oak barrel is adjusted to 10-15 mL / min·m³.