Production method of high-aroma concentrated solution

Abstract

The invention discloses a production method of a high-aroma concentrated solution, and relates to the technical field of tea leaves, and the production method comprises the following steps: firstly, preparing and screening raw materials, selecting finished tea leaves with high aroma quality or tea leaves in process, then extracting tea soup and collecting condensed water, then preparing the concentrated solution and collecting the condensed water, and then sterilizing the condensed water and the concentrated solution. Through a high-temperature sterilization technology, microorganisms in a concentrated solution are thoroughly killed, meanwhile, high-quality sterilization synergy is formed with mild sterilization of condensate water, the sanitary requirement of industrial production is met, the high-aroma core characteristic of the product is not affected, then homogenizing and shaking up are conducted, finally synchronous filling is conducted, and on the basis of accurate matching, the product quality is greatly improved. The efficient fusion of the fragrance-containing condensate water and the concentrated solution is realized, and the loss of fragrance and non-uniform mixing are avoided. According to the production method, the simple low-temperature circulating water is used for cooling the water vapor with the aroma components, so that the investment of equipment can be reduced, and meanwhile, the required aroma components can be obtained by periodically collecting the aroma.

Description

Technical Field

[0001] This invention relates to the field of tea technology, specifically to a method for producing a highly aromatic concentrated liquid. Background Technology

[0002] Tea concentrate is a product made through tea extraction, filtration, concentration, sterilization, and bottling processes. It is an important raw material for beverages and other end products, and it needs to maintain its good sensory flavor. Compared to tea leaves, tea concentrate reduces the extraction steps for users, requiring only subsequent blending; compared to instant tea powder, tea concentrate eliminates a drying process, resulting in less aroma loss.

[0003] Existing technologies include the use of aroma recovery devices to fill the concentrate. To achieve better flavor, enzymes and flavorings are also added to enhance the aroma of the concentrate.

[0004] For example, patent CN120360173A discloses a caffeine-free tea concentrate, relating to the food processing field. This caffeine-free tea concentrate includes aroma extract A and flavor concentrate B, which are compounded and refined to obtain the caffeine-free tea concentrate. Aroma extract A is prepared through raw material processing, low-temperature vacuum steam extraction, and condensation collection steps. Flavor concentrate B is prepared through rooibos tea pretreatment, water extraction concentration, and enzymatic hydrolysis enhancement steps. This caffeine-free tea concentrate, through the synergistic effect of supercritical carbon dioxide deodorization and natural caffeine-free rooibos tea, ensures that the caffeine content of the final product is below the detection limit, far lower than the residual levels of traditional methods. Low-temperature vacuum steam extraction avoids the degradation of heat-sensitive aroma components, and combined with condensation collection technology, it achieves a high retention rate of volatile aroma components, significantly superior to the supercritical carbon dioxide method.

[0005] For example, patent CN107912565A discloses a method for simultaneously preparing tea concentrate and tea aroma substances, belonging to the field of food processing technology. It employs twin-screw extrusion and vacuum critical point concentration technology to subject tea leaves to high-pressure cell wall disruption and recover tea aroma substances. Through a compound enzymatic hydrolysis process, tea polyphenols and aromatic substances are extracted from tea leaves at room temperature, achieving high extraction rates and preserving the unique aroma of tea. This simultaneously produces tea concentrate and natural aroma substances from tea leaves. The combined use of multiple advanced technologies can reduce reliance on heating extraction and cold rinsing for concentration, lowering production costs. Furthermore, by fully utilizing the abundant non-water-soluble proteins and cellulose in tea, the deep development and comprehensive utilization of tea proteins and cellulose can not only reduce environmental pollution but also create significant social and economic benefits, having profound implications for the development of science, technology, the economy, and the food industry.

[0006] However, the aforementioned applications involve complex processes and require sophisticated equipment, making them unsuitable for low-cost, large-scale production. Furthermore, while the mainstream UHT sterilization process in existing technologies can ensure the microbial safety of the product, high temperatures can lead to a significant loss of the natural aroma components of tea. Traditional aroma recovery equipment, such as rotary cone distillation towers, is too expensive and difficult to apply to the production of tea concentrate products with lower added value.

[0007] To address the aforementioned issues, there is an urgent need for innovative designs based on existing estimation methods. Summary of the Invention

[0008] The purpose of this invention is to provide a method for producing high-aroma concentrate, in order to solve the problems in the background technology, such as complex processes, high equipment requirements, unsuitability for low-cost large-scale production, and the fact that although the mainstream UHT sterilization process in the prior art can ensure the microbial safety of the product, high temperature will cause a large loss of the natural aroma components of tea; and traditional aroma recovery equipment such as rotary cone distillation towers are too expensive and difficult to apply to the production of tea concentrate products with low added value.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a method for producing a high-fragrance concentrate, comprising the following steps:

[0010] Step S1, Raw material preparation and screening: Select finished tea leaves or tea leaves with high aroma quality, and remove impurities, old stems and non-tea substances to ensure the aroma quality, purity and subsequent processing stability of the product from the source.

[0011] Step S2, tea liquor extraction and condensate collection, involves extracting tea liquor from the tea leaves processed in step S1, laying a crucial foundation for the high aroma quality of subsequent processes and the final product.

[0012] Step S3, concentrate preparation and condensate collection, are used to build a rich flavor base for the product, maximize the recovery of the natural aroma of tea, and provide data support for subsequent proportioning.

[0013] Step S4, condensate sterilization, is used to remove microorganisms in the fragrance-containing condensate, ensuring product hygiene and safety, while retaining the natural fragrance components in the condensate to the greatest extent, laying a good foundation for subsequent mixing with the concentrate;

[0014] Step S5, concentrate sterilization: through high-temperature sterilization process, microorganisms in the concentrate are thoroughly killed, while the mild sterilization of condensate water forms a high-quality sterilization synergy, which not only meets the hygiene requirements of industrial production, but also does not affect the core characteristics of the product's high aroma.

[0015] Step S6: Homogenize and shake well. Physical agitation is used to achieve deep integration of the flavoring components and the concentrate, eliminating problems such as uneven mixing and layering, and ensuring the uniformity of product flavor and the stability of product quality.

[0016] Step S7, synchronous filling, achieves efficient fusion of flavored condensate and concentrate based on precise proportions, avoids aroma loss and uneven mixing, and ensures rich aroma and uniform quality of the product.

[0017] Preferably, step S2 is performed as follows: first, tea leaves treated in step S1 are added to a special extraction tank, and extraction water at 60℃-100℃ is added, and the tea-to-water ratio is controlled at 1:10-1:20 for extraction.

[0018] Preferably, the specially designed extraction tank has its lower end of the feeding port immersed in the extraction solvent to reduce the raising of tea dust, and the extraction time is 30-90 minutes.

[0019] Preferably, in step S2, the condensate is collected by circulating water through a pipeline to collect the water vapor of the aroma-containing substances that evaporate during the extraction process, resulting in condensate D1 and a measured volume V1.

[0020] Preferably, step S3 is performed by using a vacuum concentration device to concentrate the extract obtained in step S2 to a concentration of 20%-25%, and measuring the volume of the concentrated liquid V2.

[0021] Preferably, the condensate from the vacuum concentration process is collected in segments at 10-20 minute intervals, with only the condensate from the first 10-20 minutes retained as D2 and its volume measured as V3.

[0022] Preferably, step S4 is carried out by mixing condensate D1 and D2, then sterilizing them by membrane filtration to trap microorganisms and retain aroma substances, and the membrane filtration uses a ceramic membrane with a pore size of no more than 0.05 μm.

[0023] Preferably, the sterilization method in step S5 is to use a UHT device to sterilize the concentrate obtained in step S3, and the sterilization temperature of the UHT is set to 130°C.

[0024] Preferably, the specific method in step S6 is as follows: according to the ratio of (V1+V3):V2, a double-head filling device is used to simultaneously fill the flavored condensate sterilized in step S4 and the concentrate sterilized in step S5.

[0025] Preferably, the extract in step S2 is filtered through a 500-mesh cloth bag and the tea residue is squeezed before entering step S3 for concentration.

[0026] Compared with the prior art, the beneficial effects of the present invention are:

[0027] 1. Using simple low-temperature circulating water to cool water vapor containing aroma components can reduce equipment investment, and at the same time, the desired aroma components can be obtained by collecting aroma in stages;

[0028] 2. Currently, UHT is the mainstream sterilization equipment for beverage processing. However, UHT sterilization equipment causes significant loss of aroma. By using appropriate sterilization methods for aroma components and concentrates respectively, the loss of aroma can be reduced, thus ensuring the quality of the final product. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall production method of the present invention.

[0030] Figure 2 This is a schematic diagram of the tea infusion extraction and condensate collection process of the present invention. Detailed Implementation

[0031] 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, and 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.

[0032] This application provides a method for producing a high-fragrance concentrate. To better understand the above technical solution, it will be described in detail below with reference to the accompanying drawings and specific embodiments. Figures 1-2 As shown in this embodiment of the present application, a method for producing a high-fragrance concentrate includes the following steps:

[0033] Step S1, Raw material preparation and screening: Select finished tea leaves or tea leaves with high aroma quality. The raw material used is Da Hong Pao Oolong tea. Remove impurities, old stems and non-tea substances to ensure the aroma quality, purity and subsequent processing stability of the product from the source.

[0034] In practice, the first step is to select tea types with distinct aroma characteristics that meet the high-aroma requirements of the finished product. Priority should be given to finished tea products or in-process teas with stable quality (such as the richly aromatic Da Hong Pao Oolong tea). Avoid using raw materials with weak aroma, spoilage, or abnormal flavor. Select teas of corresponding grades based on product positioning, prioritizing plump buds and leaves with pure aroma, and eliminating teas with a high proportion of old leaves and strong off-flavors to ensure the raw materials themselves have sufficient reserves of natural aroma substances. Then, pre-processing is carried out through manual sorting to remove large, visible impurities from the tea leaves, including but not limited to old stems, tea fruits, and plant residues (such as impurities). Grass, twigs, stones, and plastic scraps are used to initially improve the purity of the raw materials. If the tea leaves are too large (such as whole tea stems or compressed tea blocks), they can be lightly crushed to ensure that aroma substances and flavor components can be fully dissolved during subsequent extraction. However, the particle size of the crushed leaves must be controlled to avoid generating too much tea dust. Next, a fine screening process is carried out. Utilizing the difference in electrostatic adsorption between tea leaves and impurities (such as dust and fine fibers), electrostatic impurity removal equipment adsorbs and separates fine dust, fuzz, and other light impurities from the tea leaves, reducing the risk of dust being stirred up during subsequent extraction. A color sorter is used to accurately identify and remove impurities based on the color difference between the tea leaves and impurities. Discoloration and impurities (such as brown old leaves, black scorched leaves, yellow grass clippings, etc.) are removed, while tea leaves with uniform color and consistent quality are selected to ensure the uniformity of raw materials. Then, an electromagnetic iron removal device adsorbs metal fragments mixed in with the tea leaves (such as iron filings, nails, etc. that may remain from processing), preventing metal impurities from affecting product safety or damaging subsequent extraction and concentration equipment. X-ray detection technology is used to detect and separate high-density foreign objects (such as small stones, glass fragments, metal particles, etc.) that are difficult to see with the naked eye, further improving the purity of the raw materials and ensuring the product has no safety hazards. Finally, quality inspection is conducted to ensure that the raw materials meet standards, and specialized personnel can be organized to conduct further inspections. Industry personnel inspect the aroma, taste, and appearance of the selected tea leaves to ensure that the aroma is pure and free of off-odors (such as musty, sour, or burnt smells), and that the appearance is uniform and free of obvious impurities. They can also sample and test the raw materials according to production needs to confirm that indicators such as moisture content and aroma substance content meet production requirements (e.g., moisture content needs to be controlled within a safe range to prevent raw materials from becoming moldy), ensuring the stability of raw material quality. They can also store qualified raw materials by batch and label them (such as raw material name, batch, and screening date) to avoid mixing raw materials of different batches and qualities and to ensure batch stability in subsequent production.

[0035] In this embodiment, by preparing and screening raw materials, the aroma base of the raw materials can be guaranteed, laying the foundation for the high aroma of the product. Removing impurities can avoid interference from unpleasant flavors, ensuring the uniformity of raw materials, improving the stability of the production process, and adapting to the needs of subsequent processes, thus reducing process interference.

[0036] Step S2, tea infusion extraction and condensate collection, involves extracting tea infusion from the tea leaves processed in step S1. This lays a crucial foundation for the high aroma quality of subsequent processes and the final product. This can be achieved through the following steps:

[0037] Step S21, preliminary preparation, pre-processing of equipment and materials;

[0038] Step S22, when feeding the pre-treated raw materials, requires precise control of the tea-to-water ratio;

[0039] Step S23 involves extraction, which requires controlling the temperature and time to ensure the dissolution of components.

[0040] Step S24: Condensate collection, directional capture of perfume vapor;

[0041] Step S25: Extraction complete. Temporarily store the extract and condensate.

[0042] In practice, the equipment and materials are first pre-treated. The special extraction tank (with an immersion design for the feeding port, a stirring device, and an exhaust port), the circulating water cooling system, the refrigeration equipment, and the condensate collection tank are checked for leaks and operational status to ensure no leaks and unobstructed pipelines. Next, the refrigeration equipment is adjusted to lower the circulating cooling water temperature to 10-15℃ (to ensure rapid condensation of water vapor), and the metering device of the condensate collection tank is calibrated (to ensure accurate measurement of volume V1). Then, the extraction tank needs to be cleaned and the pipelines reconnected to remove residual impurities or materials from previous batches to avoid contaminating the current extract. Finally, the tea leaves, after preparation and screening, are taken, and the feeding amount is determined according to the production batch (e.g., 200kg of Da Hong). Prepare the tea leaves by ensuring they are uniform in shape (if there are large clumps of tea, gently break them up to avoid uneven extraction). Use food-grade extraction water (such as purified water) preheated to a preset temperature range (60℃-100℃, adjusted according to the type of tea; for example, 85-90℃ is preferred for oolong tea). Then, open the feeding port of the special extraction tank and slowly add the pre-treated tea leaves, ensuring they are evenly spread to avoid localized accumulation and insufficient extraction. Pour the preheated extraction water into the tank at a tea-to-water ratio of 1:10-1:20 (mass-volume ratio, e.g., 200kg tea to 3700L water), ensuring the water completely covers the tea leaves and the bottom of the feeding port is immersed in the extraction solution. Add the agent (to reduce tea dust), then close the feeding port and tank door, check the sealing condition inside the tank to prevent water vapor leakage during extraction; start the stirring device of the extraction tank (speed controlled at 30-50 r / min) to ensure full contact between the tea leaves and the extraction water, avoiding excessively high local temperatures or uneven dissolution, and maintaining the extraction temperature inside the tank within the preset range (60℃-100℃). Monitor the temperature in real time through the temperature control system to avoid excessive temperature fluctuations (such as insufficient dissolution of aroma substances due to low temperature, and burnt taste due to high temperature). Continue extraction for the preset time (30min-90min, such as 90min for Da Hong Pao extraction). Observe the state inside the tank regularly during the extraction process to ensure there is no abnormal boiling. Issues such as leakage; after extraction begins, the pipeline circulating water cooling system and refrigeration equipment are started simultaneously, so that the circulating cooling water continues to circulate in the condensation pipe, forming a low-temperature condensation environment. The water vapor of the aroma-containing substances volatilized during the extraction process enters the condensation pipe through the exhaust port at the top of the extraction tank. After sufficient heat exchange with the low-temperature circulating cooling water, it quickly condenses into liquid aroma-containing condensate (i.e., D1). The condensate flows into a dedicated collection tank along the pipeline. During the collection process, the volume of condensate V1 is recorded in real time to ensure accurate measurement. During the collection process, the condensation pipeline is checked regularly to ensure that it is unobstructed and the temperature of the refrigeration equipment is stable, so as to avoid the aroma substances not being completely captured due to insufficient condensation efficiency (such as pipeline blockage or excessively high cooling water temperature).After the preset extraction time is reached, first turn off the heating device, then keep the stirring device running for 5 minutes to allow the remaining aroma substances in the tank to fully volatilize and be condensed and collected. Stop the stirring and circulating water cooling system, and seal the collected aroma-containing condensate D1 in a cool environment to prevent aroma volatilization. Mark the batch number, volume V1, and other information. Open the discharge valve at the bottom of the extraction tank to slowly release the extract. Perform preliminary filtration (e.g., using a 500-mesh cloth bag filter) to remove tea residue, and collect the filtrate for later use (the filtrate should be used in the subsequent concentration process as soon as possible to avoid flavor loss). Then, squeeze the tea residue in the extraction tank to recover the remaining tea liquid, improving raw material utilization, and finally discard the tea residue.

[0043] It should be noted that in this application, the tea-to-water ratio, extraction temperature, and extraction time need to be adjusted according to the type of tea: for example, green tea requires a lower temperature (60-70℃) and a shorter time (30-40min) to avoid bitterness; black tea and oolong tea can use a higher temperature (80-90℃) and a longer time (60-90min) to fully extract aroma and flavor substances; the condensation pipe needs to be cleaned regularly to remove residual tea stains or impurities from the inner wall to avoid affecting condensation efficiency or contaminating the condensate; the aroma-containing condensate D1 needs to be stored separately to avoid confusion with the condensate D2 in the subsequent concentration stage to ensure accurate subsequent proportions; and if equipment failure occurs during the extraction process (such as heating interruption or condensation system failure), the extraction must be stopped immediately, and the materials must be properly disposed of to avoid waste of raw materials or damage to product quality.

[0044] In this embodiment, the core flavor and nutrients of tea can be efficiently extracted by tea infusion extraction and condensate collection, constructing the product flavor base. High-purity natural aroma substances can be recovered in stages, locking in the core aroma of the product. Furthermore, precise measurement provides data support for subsequent proportional filling and can also work with subsequent processes to reduce the risk of secondary aroma loss.

[0045] Step S3, concentrate preparation and condensate collection, are used to build a rich flavor base for the product, maximize the recovery of the natural aroma of tea, and provide data support for subsequent proportioning.

[0046] In practice, the filtrate obtained from the tea extraction and condensate collection processes is first filtered a second time through a 500-mesh cloth bag to thoroughly remove residual fine tea leaves, tea dust, and other impurities. This prevents impurities from adsorbing aroma substances or clogging the vacuum concentration equipment pipes during the concentration process. The filtered filtrate is then allowed to stand briefly (10-15 minutes) to further settle fine suspended solids. The supernatant is used as the concentration raw material to ensure the purity and lack of turbidity of the subsequent concentrate. The initial volume and concentration of the pretreated filtrate are measured to provide a reference for subsequent concentration endpoint control. Then, the sealing and operating status of the vacuum concentration equipment (such as a vacuum evaporator), condensate pipes, circulating water cooling system, and D2 collection tank are checked to ensure that there are no leaks in the equipment, the vacuum system is normal, and the pipes are unobstructed. The parameters of the vacuum concentration equipment are adjusted, and the vacuum degree is set to -0.08 to -0.0.09MPa (low temperature and low pressure environment reduces damage to heat-sensitive materials), preheat the equipment jacket (or heating components) to the preset temperature (matched according to the vacuum level, usually 50-70℃), and calibrate the metering device of the D2 collection tank to ensure accurate measurement of volume V3. Simultaneously, confirm that the circulating water cooling system temperature is stable at 10-15℃ to ensure rapid condensation of water vapor. Clean the inner walls of the equipment and pipe connections to remove residual materials from the previous batch and avoid contaminating the current concentrate. Then, slowly inject the pretreated filtrate into the vacuum concentrator through the feed pump, ensuring the feed rate does not exceed 80% of the equipment's rated capacity to prevent liquid overflow during concentration. Start the vacuum system and wait for the vacuum level inside the equipment to stabilize. After setting the range, turn on the heating device to begin the concentration operation. Simultaneously, start the equipment's stirring device (20-30 r / min) to ensure even heating of the filtrate and prevent localized overheating that could produce a burnt smell. During concentration, monitor the concentration changes of the filtrate in real time. Use an online concentration meter (such as a Brix meter) or sampling to track the concentration towards the target value of 20%-25%, maintaining stable vacuum and heating temperature to prevent parameter fluctuations from causing a decrease in concentration efficiency or deterioration of the filtrate. If a decrease in vacuum or abnormal temperature occurs, immediately stop the machine for troubleshooting. After concentration starts, simultaneously open the condensate collection valve to collect only the perfume-containing vapors that evaporate in the first 10-20 minutes of concentration. The evaporated water vapor, rich in the high-value aroma components remaining from the tea leaves, is rapidly condensed by the circulating water cooling system and flows into a dedicated collection tank, which is called condensate D2. The collection volume V3 of D2 is recorded in real time and batch identification is properly done. When the concentration time exceeds 20 minutes, the D2 collection valve is closed. Subsequent evaporated water vapor is no longer collected because it is prone to producing unpleasant odors such as burnt smells. When the concentration of the liquid reaches the target range of 20%-25%, the heating device is first turned off, and the vacuum system and stirring device are kept running for 5 minutes to recover the small amount of aroma substances remaining in the equipment (still included in the D2 collection). The vacuum system and stirring device are then turned off, and the vacuum state in the equipment is slowly broken (to avoid sudden pressure changes that could damage the liquid). (Liquid splashing) completes the concentration operation; then, open the discharge valve of the vacuum concentration equipment to transfer the concentrated liquid (volume V2) through a sterile pipeline to a dedicated sealed storage tank. The storage tank must be cleaned and disinfected in advance to avoid contamination. During the temporary storage period, the concentrated liquid must be kept at a low temperature (10-15℃) and enter the subsequent UHT sterilization process within 2 hours to prevent microbial growth or loss of flavor substances. The collected condensate D2 is sealed and stored in a cool environment, labeled with batch number, volume V3, and other information, and stored separately from the previously collected D1 to avoid confusion and ensure accurate subsequent proportioning. Clean the vacuum concentration equipment, condensate pipeline, and collection tank to remove residual concentrated liquid or tea stains from the inner wall, preparing for the next batch of production.

[0047] It should be noted that in this application, the concentration time must be strictly controlled. The first 10-20 minutes are the critical window for D2 collection. Closing the collection valve too early or too late will result in the loss of high-quality aroma or the introduction of unpleasant odors. The vacuum degree and heating temperature must be matched. Insufficient vacuum degree will cause the concentration temperature to rise, damaging heat-sensitive flavor substances; excessive vacuum degree will reduce the concentration efficiency and increase energy consumption. The D2 collection tank must be dedicated to avoid cross-contamination with condensate from other processes, and it must be sealed as soon as possible after collection to reduce aroma volatilization. The concentration parameters can be fine-tuned for different types of tea. For example, the concentration temperature of green tea can be slightly lower (50-60℃), while that of black tea and oolong tea can be appropriately increased (60-70℃) to ensure a balance of flavor and aroma.

[0048] In this embodiment, flavor substances can be concentrated through concentrate preparation and condensate collection to build a rich and mellow flavor base for the product. During the concentration process, tea leaves will continue to volatilize some aroma substances, and the aroma components at this stage are different from those in the extraction stage. The core function of condensate collection is to accurately capture this remaining high-value aroma and avoid loss. Through precise measurement, it provides key data support for subsequent proportioning and mixing, and can also optimize raw material utilization and reduce production costs.

[0049] Step S4, condensate sterilization, is used to remove microorganisms in the fragrance-containing condensate, ensuring product hygiene and safety, while retaining the natural fragrance components in the condensate to the greatest extent, laying a good foundation for subsequent mixing with the concentrate;

[0050] In practice, firstly, a ceramic membrane filtration device with a pore size no larger than 0.05μm is selected (suitable for the sterilization of aroma-containing condensate, retaining microorganisms while allowing aroma substances to pass through). The integrity of the membrane components, pipes, and seals is checked to ensure there is no damage or leakage. Then, the membrane filtration device is pre-treated: first, the inside of the device and pipes are rinsed with purified water for 3-5 minutes to remove residual impurities, then circulated and cleaned with 80-85℃ hot water for 20 minutes, or disinfected with a food-grade disinfectant (such as diluted peracetic acid solution) for 30 minutes. Afterward, it is thoroughly rinsed with purified water until no disinfectant residue remains, ensuring the device is sterile. The operating parameters of the device are then adjusted, i.e., the filtration pressure is set to 0.2-0.3MPa, the filtration temperature to 15-25℃ (low temperature to avoid aroma volatilization), and the flow rate to 5-10m / s, ensuring stable membrane filtration efficiency. Then, the condensate collected during the tea extraction stage is taken. D1 (volume V1) and the condensate D2 (volume V3) collected during the concentrate preparation stage are mixed according to batch ratio and poured into a dedicated sterile mixing tank. The tank is then stirred at low speed (20-30 rpm) for 5-10 minutes to ensure uniform mixing of the aroma components in D1 and D2, avoiding localized concentration differences. The mixed condensate is then preliminarily filtered through a 200-mesh filter to remove any remaining fine tea residue, dust, or other impurities, preventing clogging of the ceramic membrane pores and affecting filtration efficiency. The discharge valve of the sterile mixing tank and the feed pump of the membrane filtration equipment are then opened to slowly pump the mixed condensate into the membrane filtration system, ensuring a stable feed rate and preventing sudden pressure changes that could damage the membrane modules. During filtration, the equipment's operating status needs to be monitored in real time. During pressure monitoring, the inlet pressure should be kept stable at 0.2-0.3 MPa. If the pressure rises (exceeding 0...A pressure of 35 MPa indicates potential membrane pore blockage, requiring filtration to be paused. The membrane module should be backflushed with purified water for 5 minutes before resuming filtration. During temperature monitoring, the filtration temperature should be controlled to not exceed 25°C using a cooling device to prevent the volatilization or decomposition of aroma components (such as terpenes and aromatic alcohols) due to high temperatures. During flow monitoring, ensure a stable condensate flow rate after filtration. If the flow rate drops significantly, the membrane module should be cleaned promptly. Afterward, collect the sterilized condensate after filtration. The condensate passing through the ceramic membrane (which has already trapped microorganisms and retained aroma) should be transferred to a sterile, sealed storage tank. The storage tank must be cleaned and disinfected beforehand to avoid secondary contamination. After filtration, flush the membrane filtration equipment and pipelines with purified water for 5-10 minutes to recover any residual aroma-containing condensate and reduce losses. Then, transfer the condensate from the sterile storage tank... Take 3-5 samples for microbial testing (total bacterial count, mold, yeast, etc.), requiring a total bacterial count ≤10 CFU / mL. Simultaneously, perform sensory evaluation to confirm the condensate has a pure aroma and no off-odors, ensuring that the core aroma components are retained after sterilization. Store the qualified sterilization condensate in a sealed container at a low temperature of 10-15℃, avoiding direct sunlight, and proceed to the subsequent synchronous filling process within 4 hours to minimize aroma evaporation. After using the membrane filtration equipment, immediately backwash the membrane module with purified water for 10 minutes to remove impurities trapped on the membrane surface. If the membrane is severely fouled, it can be circulated and cleaned for 30 minutes with a diluted citric acid solution (2%-3% concentration), then rinsed with purified water until neutral, air-dried, and sealed for storage to extend the membrane module's lifespan.

[0051] It should be noted that in this application, temperature and pressure must be strictly controlled during the membrane filtration process. Low temperature and low pressure can avoid aroma loss and protect the filtration performance of the ceramic membrane. D1 and D2 should be mixed according to the corresponding batches to avoid cross-contamination of condensate from different batches and ensure the consistency of aroma components. All equipment that comes into contact with condensate (mixing tank, storage tank, pipeline) must meet food-grade standards and must be disinfected before each use to prevent microbial contamination. If the volume of mixed condensate is large, membrane filtration can be carried out in batches, but it is necessary to ensure that the equipment parameters are consistent for each batch to avoid differences in sterilization effect and aroma retention rate.

[0052] In this embodiment, the sterilization of condensate water, through a gentle membrane filtration process, not only solves the problem of microbial contamination in the aroma-containing condensate water and meets food safety requirements, but also avoids the destruction of aroma caused by traditional high-temperature sterilization, maximizing the preservation of natural aroma components. This forms a synergistic design with the subsequent sterilization of the concentrate (UHT high-temperature sterilization), which overcomes the technical shortcomings of the difficulty in balancing sterilization and aroma preservation from a process perspective, and provides key support for the rich aroma, safety and stability of the final product.

[0053] Step S5, concentrate sterilization: through high-temperature sterilization process, microorganisms in the concentrate are thoroughly killed, while the mild sterilization of condensate water forms a high-quality sterilization synergy, which not only meets the hygiene requirements of industrial production, but also does not affect the core characteristics of the product's high aroma.

[0054] In practice, the concentrate obtained from the concentrate preparation process (concentration 20%-25%, volume V2) is first filtered a second time through a 300-mesh filter to remove any remaining fine tea residue, suspended solids, or other impurities. This prevents impurities from affecting the sterilization effect or clogging the UHT equipment pipes. The storage status of the concentrate must also be checked to ensure that the temperature is controlled at 10-15℃ during storage (≤2 hours), and that there is no microbial growth or off-odors (such as burnt or sour smells). If any abnormalities are found, the concentrate must be discarded to avoid affecting the quality of the finished product. The concentration is then measured. Record the initial temperature and concentration of the liquid to provide a reference for fine-tuning the UHT sterilization parameters. Then, perform CIP (clean-in-place) disinfection on the UHT equipment. First, circulate and rinse the inside of the equipment and pipes with 80-85℃ hot water for 15 minutes to remove residual materials. Then, circulate and clean with a food-grade alkaline cleaning agent (such as diluted sodium hydroxide solution, concentration 2%-3%) at 60-70℃ for 30 minutes to remove contaminants such as grease and tea stains. Rinse with purified water until the pH of the equipment outlet water is neutral (pH 6.5-7.5). Finally, rinse with 95-100... Sterilize with hot water circulation for 20 minutes at ℃. After completion, cool the equipment to room temperature to ensure sterility inside. Set sterilization parameters according to the characteristics of the concentrate: sterilization temperature 130℃, holding time 2-4 seconds (ultra-high temperature instantaneous, reducing damage to heat-sensitive substances). Then set cooling parameters: after sterilization, the concentrate needs to be rapidly cooled to 15-20℃ (to avoid prolonged high temperature affecting flavor). Cooling method uses cold water circulation heat exchange. Then set the feed rate, adjusting according to the equipment's rated capacity, to ensure the concentrate's residence time in the insulation tube accurately reaches the set holding time, avoiding sterilization... Incomplete or excessive sterilization occurs. Afterward, start the UHT equipment's feed pump and slowly pump the pretreated concentrate into the equipment. Gradually increase the feed rate to stabilize it, avoiding sudden pressure changes that could cause equipment malfunction or concentrate splashing. During sterilization, key indicators must be monitored in real time. For temperature monitoring, use the equipment's built-in temperature sensor to track the sterilization zone temperature in real time, ensuring it remains stable at 130℃±1℃. If the temperature fluctuation exceeds ±2℃, immediately stop the machine and investigate to ensure sterilization effectiveness is met. For pressure monitoring, maintain the internal pressure of the equipment stable at 0.3-0.A pressure of 4 MPa is used to prevent the concentrate from boiling over at high temperatures and to ensure uniform heating. For flow monitoring, the feed flow rate must be matched with the holding time; if the flow rate is abnormal, the pump speed must be adjusted to ensure consistent sterilization conditions for each batch of concentrate. After sterilization in the holding section, the concentrate immediately enters the cooling section, where the temperature is rapidly reduced to 15-20℃ via cold water circulation, shortening the high-temperature exposure time and reducing the oxidation loss of flavor substances such as tea polyphenols and amino acids. The cooled concentrate is then transported through sterile pipelines to a dedicated sterile sealed storage tank. The storage tank must be pre-sterilized using CIP to avoid secondary contamination. Afterward, 3-5 samples are taken from the sterile storage tank. Microbiological testing (total bacterial count, pathogenic bacteria, spores, etc.) is performed, requiring a total bacterial count ≤10 CFU / mL and no detection of pathogenic bacteria or spores. Simultaneously, sensory evaluation is conducted to confirm the concentrated liquid has a mellow taste, no burnt or off-flavors, and retains the original flavor of the tea. The qualified sterilized concentrated liquid is sealed and stored in a low-temperature environment of 10-15℃, avoiding direct sunlight, and must be introduced into the subsequent synchronous filling process within 4 hours to prevent secondary microbial growth or flavor loss. After sterilization, the UHT equipment is immediately cleaned using CIP (Clean-In-Place) technology, following the same procedure as pre-sterilization disinfection, to remove residual concentrated tea residue from the equipment's inner walls and avoid affecting the next batch of production.

[0055] It should be noted that the core of UHT sterilization in this application is high-temperature instantaneous sterilization. The matching of temperature and holding time must be strictly controlled. Holding at 130℃ for 2-4 seconds can thoroughly kill microorganisms while minimizing flavor damage. Parameters should not be adjusted arbitrarily. All pipes and storage tanks that come into contact with the sterilized concentrate must be made of food-grade sterile materials and must be disinfected before each use to prevent cross-contamination. Before feeding the concentrate, it must be ensured that there are no large particulate impurities to avoid clogging the insulation pipes or nozzles of the UHT equipment and affecting the uniformity of sterilization. If equipment failure occurs during production (such as a sudden drop in temperature or abnormal pressure), feeding must be stopped immediately, and the unsterilized concentrate in the equipment must be discarded to prevent unqualified products from flowing into subsequent processes.

[0056] In this embodiment, the sterilization of the concentrate is carried out through the UHT process to completely solve the problem of microbial contamination of the concentrate, ensuring product safety and shelf life. At the same time, it forms a precise division of labor with the mild sterilization of the condensate, avoiding the destruction of aroma components by high temperature. This perfectly matches the core goal of this application of producing a rich aroma without any exogenous additives, and provides key support for the safety, stability and high fragrance of the final product.

[0057] Step S6: Homogenize and shake well. Physical disturbance is used to achieve deep integration of the flavoring components and the concentrate, eliminating problems such as uneven mixing and layering, and ensuring the uniformity of product flavor and quality stability.

[0058] In practice, first confirm that the microbial indicators and sensory quality of the aroma-containing condensate (sterilized by membrane filtration) and concentrate (sterilized by UHT) meet the standards, with a storage time of ≤4 hours to avoid aroma loss or microbial growth. Based on the preset ratio of (V1+V3):V2, verify the volumes of the two materials, calculate the total production usage, and ensure sufficient materials and accurate proportions. Start low-speed stirring in both the aroma-containing condensate and concentrate storage tanks for 5-10 minutes to ensure uniformity of each material and avoid localized concentration differences. Simultaneously, [the process is repeated in the original text]. The material temperature is stabilized at 15-20℃. Both materials are filtered twice through a 300-mesh filter to remove fine impurities (such as residual tea leaves and dust) to prevent clogging of the Venturi tube throat and affecting the homogenization effect. Then, the Venturi tube is disassembled (if the structure allows) and the tube cavity (especially the throat and diffuser section) is rinsed with purified water to remove residual impurities. Then, it is rinsed with 80-85℃ hot water for 20 minutes or disinfected with diluted food-grade peracetic acid solution for 30 minutes. Finally, it is rinsed with purified water until no disinfectant residue remains, and the inside of the tube is dried with sterile air. Moisture is removed from the conveying pipeline connecting the Venturi tube and the filling head, and the dual-head filling equipment (or single-head integrated filling head) undergoes CIP online cleaning and disinfection, following the same process as the Venturi tube, ensuring complete sterility and no cross-contamination. The aroma-containing condensate storage tank and the concentrate storage tank are connected to the main inlet and side inlet of the Venturi tube respectively via independent sterile pipelines (typically, the concentrate is used as the main fluid, and the aroma-containing condensate as the secondary fluid, utilizing the negative pressure of the main fluid to draw in the secondary fluid). The outlet of the Venturi tube is connected to the filling head of the filling equipment via a sterile pipeline. Precision flow meters and variable frequency feed pumps are installed on the two raw material pipelines respectively. Pressure sensors and online concentration meters are installed at the Venturi tube outlet to ensure that flow rate, pressure, and concentration can be monitored in real time. Based on the material viscosity (concentrate concentration 20%-25%), the main fluid inlet pressure is set to 0.3-0.4 MPa, and the negative pressure at the Venturi tube throat is controlled at -0.02 to -0.03 MPa to ensure that the secondary fluid can be stably drawn in and fully mixed. The outlet pressure is stabilized at 0.1-0.2 MPa to avoid material splashing due to excessive pressure.

[0059] It should be noted that in this application, the selection of the Venturi tube must be adapted to the characteristics of the materials. Based on the flow rate and viscosity of the mixture, a Venturi tube with a suitable throat diameter should be selected to ensure that the main fluid can form sufficient negative pressure to achieve full shear mixing of the two materials. The pipe connecting the Venturi tube and the filling head should be shortened as much as possible, and right-angle bends should be reduced to avoid the mixture from stagnating in the pipe and causing stratification. If flow fluctuations occur during production, the frequency converter pump should automatically adjust the pressure to ensure accurate proportions. After production, the Venturi tube throat should be back-flushed with purified water immediately to remove residual mixture and prevent tea stains from accumulating and affecting the homogenization effect in the next process. The Venturi tube should be disassembled and thoroughly cleaned weekly to check for wear on the throat. The temperature of the two materials and the mixture should be maintained at 15-25℃ throughout the process to prevent high temperatures from causing the aroma components to volatilize or decompose, affecting the product flavor.

[0060] In this embodiment, homogenization and shaking can achieve deep and uniform fusion, lock in aroma components, reduce secondary volatilization loss, ensure batch and single-can uniformity, and improve product standardization. Homogenization and shaking can not only achieve uniform flavor, but also optimize the physical stability of the product, avoid appearance defects such as sedimentation and stratification after long-term standing of aroma components and concentrate, ensure that the product remains uniform and transparent during the shelf life, and improve visual quality.

[0061] Step S7, synchronous filling, achieves efficient fusion of flavored condensate and concentrate based on precise proportions, avoids aroma loss and uneven mixing, and ensures rich aroma and uniform quality of the product;

[0062] In practice, firstly, confirm that both the scented condensate (sterilized by membrane filtration) and the concentrate (sterilized by UHT) have completed quality testing, and that their microbiological indicators and sensory quality meet the standards. Verify the volume ratio of the two materials, and calculate the total amount of scented condensate and concentrate required for this filling process according to the preset ratio of (V1+V3):V2 (e.g., 3:10 in the example). Ensure sufficient material and accurate proportions. Start low-speed stirring (15-20 r / min) in both the scented condensate and concentrate storage tanks for 5 minutes to ensure material homogeneity and avoid localized concentration differences. Then, the equipment is cleaned and disinfected. This involves performing CIP (Clean-In-Place) online cleaning and disinfection on the dual-head filling equipment (including two independent filling heads, material conveying pipes, and metering devices). First, rinse the pipes and filling heads with purified water for 3-5 minutes to remove residual impurities. Then, circulate and clean with 80-85℃ hot water for 20 minutes, or circulate and disinfect with a food-grade disinfectant (such as diluted peracetic acid solution) for 30 minutes. Finally, rinse with purified water until no disinfectant residue remains, and dry the pipes with sterile air to ensure the equipment is sterile. Next, the packaging materials are treated, using sterile glass bottles or food-grade plastic containers, which are then washed... After cleaning and high-temperature sterilization (121℃, 30 minutes) of the bottle machine, the bottles are transported to the filling station via an aseptic conveyor belt to avoid secondary contamination. Auxiliary equipment is then inspected to ensure the aseptic conveyor belt and sealing equipment (such as capping machines and stoppering machines) are functioning properly, and that the sealing materials (caps, sealing rings) meet food-grade standards and have been sterilized. The filling workshop is then ensured to be in a sterile environment (cleanliness level ≥ 100,000), with temperature controlled at 18-22℃ and humidity at 50%-60% to prevent aroma evaporation or condensation of packaging materials due to high temperature and humidity. Operators wear aseptic work clothes, gloves, and masks. After being disinfected in an air shower, the materials enter the workshop to avoid personnel contamination. Then, the two filling heads of the dual-head filling equipment are connected to the flavored condensate storage tank and the concentrate storage tank respectively through sterile pipes, ensuring the pipes are sealed without leaks and cross-contamination. The production line is started, sequentially activating the sterile conveyor belt, the dual-head filling equipment, and the sealing equipment, ensuring that the operating rhythm of each piece of equipment is synchronized (conveyor belt speed matches filling speed), with simultaneous feeding and filling. The discharge pumps of the flavored condensate and concentrate storage tanks are started, conveying the two materials to their respective filling heads, ensuring stable feeding pressure (0.1-0.5).(2MPa) To avoid flow rate fluctuations affecting measurement accuracy, when the packaging container is conveyed to the filling station, two filling heads start simultaneously, injecting the flavored condensate and concentrate into the container at the same time. During the injection process, the two materials mix naturally in the container, and the slight disturbance caused by the container movement achieves initial uniform fusion. The filling head rises and falls synchronously with the container height (to avoid material splashing). After filling to the preset mark, the filling head automatically closes, and the anti-drip device is activated to prevent residual material from contaminating the container opening. Continuous filling is monitored, and the filling volume is sampled and checked (weighed with an electronic scale) every 10 bottles / cans to ensure that the actual ratio of flavored condensate to concentrate meets the preset requirements. If a deviation occurs, the equipment measurement is adjusted immediately. Parameters are monitored during the filling process to observe for dripping, material overflow, container damage, etc. Any abnormalities are immediately addressed by stopping the machine. Filled products are quickly conveyed to the sealing station via conveyor belt, where a capping machine (or stopper) immediately completes the sealing operation, minimizing the product's contact time with air (≤30 seconds) to reduce aroma evaporation. Manual or automated inspection equipment checks the seal for tightness (e.g., whether the capping torque meets standards and the sealing ring is in place), rejecting products with loose seals or leaks. The product appearance is checked for turbidity, sediment, impurities, and whether the label is correctly affixed (if labeling is done simultaneously), ensuring the product appearance is acceptable. Information such as production batch, production date, and shelf life is printed on the product label or bottle for traceability.

[0063] It should be noted that aseptic operation is maintained throughout the entire process in this application: all equipment, pipelines, and packaging materials that come into contact with the materials must be sterile to avoid microbial contamination that could affect the product's shelf life; the mixing ratio must be strictly controlled, as the metering accuracy of the dual-head filling equipment directly determines the product's flavor, and the metering device must be calibrated regularly (once before each batch of filling) to ensure that the ratio is accurate, minimize air contact, and match the filling speed and sealing rhythm to avoid prolonged exposure of the product to air. At the same time, the container should be filled as much as possible during filling (leaving a small headspace) to reduce the oxidation loss of aroma due to headspace air. For equipment maintenance, the filling head must be disassembled and cleaned regularly to remove residual material from the inner wall to prevent bacterial growth or affecting metering accuracy. The conveyor belt and sealing equipment must be lubricated and maintained regularly to ensure stable operation.

[0064] In this embodiment, synchronous filling not only strictly executes the preset ratio through automated equipment to ensure product flavor balance and batch consistency, but also reduces aroma volatilization and mixing disturbance through synchronous injection, maximizing the preservation of natural aroma, while improving production efficiency and safety. It forms a closed loop with the previously mentioned processes such as separate sterilization and segmented aroma preservation, which can achieve the goal of rich aroma, mellow taste and stable quality without external additives. It is an indispensable key step in the production of high aroma concentrate.

[0065] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for producing a highly aromatic concentrated liquid, characterized in that, The production method includes the following steps: Step S1, Raw material preparation and screening: Select finished tea leaves or tea leaves with high aroma quality, and remove impurities, old stems and non-tea substances to ensure the aroma quality, purity and subsequent processing stability of the product from the source. Step S2, tea liquor extraction and condensate collection, involves extracting tea liquor from the tea leaves processed in step S1, laying a crucial foundation for the high aroma quality of subsequent processes and the final product. Step S3, concentrate preparation and condensate collection, are used to build a rich flavor base for the product, maximize the recovery of the natural aroma of tea, and provide data support for subsequent proportioning. Step S4, condensate sterilization, is used to remove microorganisms in the fragrance-containing condensate, ensuring product hygiene and safety, while retaining the natural fragrance components in the condensate to the greatest extent, laying a good foundation for subsequent mixing with the concentrate; Step S5, concentrate sterilization: through high-temperature sterilization process, microorganisms in the concentrate are thoroughly killed, while the mild sterilization of condensate water forms a high-quality sterilization synergy, which not only meets the hygiene requirements of industrial production, but also does not affect the core characteristics of the product's high aroma. Step S6: Homogenize and shake well. Physical agitation is used to achieve deep integration of the flavoring components and the concentrate, eliminating problems such as uneven mixing and layering, and ensuring the uniformity of product flavor and the stability of product quality. Step S7, synchronous filling, achieves efficient fusion of flavored condensate and concentrate based on precise proportions, avoids aroma loss and uneven mixing, and ensures rich aroma and uniform quality of the product.

2. The method for producing a high-fragrance concentrate according to claim 1, characterized in that: The specific method of step S2 is as follows: First, put the tea leaves that have been treated in step S1 into a special extraction tank, add extraction water at 60℃-100℃, and control the tea-to-water ratio to 1:10-1:20 for extraction.

3. The method for producing a high-fragrance concentrate according to claim 2, characterized in that: The specially designed extraction tank immerses the lower end of the feeding port into the extraction solvent to reduce tea dust from being stirred up, and the extraction time is 30-90 minutes.

4. The method for producing a high-fragrance concentrate according to claim 1, characterized in that: In step S2, the condensate is collected by circulating water through a pipeline to collect the water vapor containing aromatic substances that evaporates during the extraction process, resulting in condensate D1 and a measured volume V1.

5. The method for producing a high-fragrance concentrate according to claim 1, characterized in that: The specific method of step S3 is as follows: the extract obtained in step S2 is concentrated to a concentration of 20%-25% using a vacuum concentration device, and the volume of the concentrated liquid is measured as V2.

6. The method for producing a high-fragrance concentrate according to claim 5, characterized in that: The condensate from the vacuum concentration process is collected in segments at 10-20 minute intervals, with only the condensate from the first 10-20 minutes retained as D2, and its volume measured as V3.

7. The method for producing a high-fragrance concentrate according to claim 1, characterized in that: The specific method of step S4 is to mix the condensate D1 and D2, and then use membrane filtration to sterilize, intercept microorganisms, and retain aroma substances. The membrane filtration uses a ceramic membrane with a pore size of no more than 0.05 μm.

8. The method for producing a high-fragrance concentrate according to claim 1, characterized in that: The sterilization method in step S5 is to use a UHT device to sterilize the concentrate obtained in step S3, and the sterilization temperature of the UHT is set to 130°C.

9. The method for producing a high-fragrance concentrate according to claim 1, characterized in that: The specific method in step S6 is as follows: according to the ratio of (V1+V3):V2, a double-head filling device is used to simultaneously fill the flavored condensate sterilized in step S4 and the concentrate sterilized in step S5.

10. The method for producing a high-fragrance concentrate according to claim 1, characterized in that: Before entering step S3 for concentration, the extract from step S2 is filtered through a 500-mesh cloth bag and the tea residue is squeezed.

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