Tea drink non-thermal extraction sterilization method based on HPP and microjet technology

Abstract

The invention discloses a tea drink non-thermal extraction sterilization method based on an HPP and microjet technology, and relates to the technical field of tea drink non-thermal extraction sterilization, the method comprises the following steps: S1, raw material pretreatment; s2, HPP cold extraction treatment: placing the leaf-containing tea drink in a high-pressure cavity to destroy cell walls and promote dissolution of components; s3, filtering: filtering the leaf-containing tea drink to remove tea residues and small particles, and reserving pure tea soup; s4, carrying out microjet homogenization treatment; s5, carrying out HPP sterilization treatment; s6, finished product refrigeration: sterilizing the tea soup, transferring the sterilized tea soup to a condition of 4 DEG C for refrigeration, and storing and transporting the refrigerated tea soup under a cold chain of 2-4 DEG C; according to the tea drink non-thermal extraction sterilization method based on the HPP and the micro-jet technology, the stability and sensory quality of tea soup are optimized by using the micro-jet homogenization technology, cold extraction and sterilization are realized through ultrahigh pressure physical action, active ingredients and natural flavor of tea leaves are reserved to the maximum extent, and traditional heat treatment is replaced by virtue of the non-thermal sterilization characteristic of the HPP, so that the shelf life of a product is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of non-thermal extraction sterilization of tea beverages, and more specifically, to a non-thermal extraction sterilization method of tea beverages based on HPP and microfluidics technology. Background Art

[0002] Traditional high-temperature extraction and homogenization techniques have limited efficiency in cell wall disruption, resulting in low extraction efficiency and a long extraction time. This limits industrial production and may lead to the decomposition of theaflavins and theaflavins, changes in the structure of carotenoids and chlorophyll, and the loss of aroma components.

[0003] Although traditional thermal sterilization (such as pasteurization and high-temperature instantaneous sterilization) can achieve microbial control and ingredient extraction, it is difficult to achieve a balance between sterilization and quality, and has significant limitations: high temperature can easily destroy heat-sensitive functional components such as tea polyphenols, amino acids, and volatile aroma substances, resulting in browning of beverages, deterioration of taste, loss of flavor, and loss of nutrients;

[0004] Therefore, in response to the above-mentioned related technologies, a non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology is proposed. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, the present application provides a non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above objectives, the present application provides the following technical solutions: a non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics, including a non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics, characterized in that the method comprises the following steps:

[0007] The method comprises the following steps:

[0008] S1. Raw material pretreatment: After washing the tea leaves, the tea leaves and water are divided into sterile PET bottles at a ratio of 1:50-1:100 and sealed after filling. Alternatively, the tea leaves are stir-fried at 80°C-100°C for 5 to 10 minutes and then washed. The tea leaves and water are divided into sterile PET bottles at a ratio of 1:50-1:100 and sealed after filling.

[0009] S2.HPP cold extraction process: placing the tea leaves in a high-pressure chamber to destroy the cell walls and promote the dissolution of ingredients;

[0010] S3. Filtration: Filter the tea leaves to remove tea dregs and small particles, retaining the pure tea soup;

[0011] S4. Microfluidization: Using a microfluidizer, the tea soup is passed through a 50-200 μm pore size channel at a pressure of 200-420 MPa. This utilizes high-speed collisions, shear forces, cavitation, and turbulent vortex dispersion to break down cell walls and disperse fat-soluble components.

[0012] S5. HPP sterilization treatment: Place the tea soup in a high-pressure chamber at a pressure of 100-600 MPa and a temperature of 5-25°C for 1-10 minutes to destroy the microbial cell membrane and enzyme system to achieve sterilization;

[0013] S6. Refrigeration of finished products: After sterilization, transfer the tea soup to 4℃ for refrigeration, and store and transport it under the cold chain at 2-4℃.

[0014] Furthermore, in the S1 raw material pretreatment, the tea leaves are washed with pure running water for 2 to 10 seconds to remove debris and impurities.

[0015] Furthermore, in the S1 raw material pretreatment, the tea leaves are stir-fried at 80° C.-100° C. for 5-10 minutes to enhance the aroma and pre-sterilize the tea leaves.

[0016] Furthermore, the specific method of preparing pure tea soup from tea leaves in S1 is to mix tea leaves with water in a ratio of 1:50-1:100 to prepare leaf tea drink, and then extract the tea with HPP and filter to obtain pure tea soup.

[0017] Furthermore, the leaf tea beverage in S2 is maintained at a pressure of 100-600 MPa and a temperature of 5-25° C. in the high-pressure chamber for 1-10 minutes, and high-pressure osmosis is used to destroy cell walls and promote the dissolution of components.

[0018] Furthermore, in S3, the pure tea soup is double-filtered through a coarse filter and a multi-layer filter cloth.

[0019] Furthermore, in the S4 microfluidizer homogenization process, the tea soup is accelerated to 300-600 m / s in the microfluidizer, and collides at an angle of 60-120° in a Y-type, Z-type or composite collision chamber, and the number of treatments is 1-3 times.

[0020] Furthermore, in the HPP cold extraction treatment and the HPP sterilization treatment, the pressure transmission medium is water, and the equipment pressure fluctuation is ≤±10 MPa.

[0021] Furthermore, the method also includes performing micro-jet homogenization treatment on the tea soup before the HPP sterilization treatment to improve the stability of the tea soup and the extraction rate of active ingredients.

[0022] Furthermore, in the preparation of the leaf tea beverage, the tea leaves are mixed with water and then placed in a sterile PET bottle and sealed. After HPP cold extraction, the intact tea leaves are retained in the bottle.

[0023] The technical effects and advantages of this application are:

[0024] Compared with existing technologies, this non-thermal extraction and sterilization method for tea beverages based on HPP and microfluidization technology uses microfluidization homogenization technology to optimize the stability and sensory quality of tea soup, achieves cold extraction and sterilization through ultra-high pressure physical action, maximizes the retention of tea active ingredients and natural flavor, and uses the non-thermal sterilization properties of HPP to replace traditional heat treatment, extending the shelf life of the product, and providing multiple process paths to adapt to different tea types and product forms.

[0025] Through the synergistic effect of microfluidics and HPP, it is significantly superior to traditional processes in terms of sterilization efficiency, extraction effect, ingredient retention and sustainability, providing an innovative solution for the industrial production of high-quality tea products. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flowchart of the method of this application. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0028] Example

[0029] As attached Figure 1 The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology includes:

[0030] Tea pretreatment

[0031] Method 1: Weigh an appropriate amount of green tea leaves, put them into a pot and stir-fry them over a low heat at 80℃-100℃ (to enhance the aroma and pre-sterilize them) for 5-10 minutes, stirring constantly until the aroma comes out. After stir-frying, place the tea leaves on a filter with a pore size of 1-2mm and rinse them with pure running water for 2-10s (to remove tea leaves and surface impurities and dust, and at the same time "wake up" the tea leaves to release better aroma).

[0032] Method 2: Weigh an appropriate amount of green tea leaves, place them on a filter with a pore size of 1 to 2 mm, and rinse them with pure running water for 2 to 10 seconds (to remove tea leaves and surface impurities and dust, and at the same time "wake up" the tea leaves to release a better aroma). Only perform the rinsing step and do not do any other treatment.

[0033] Tea preparation

[0034] Method 1: Tea leaves and water are divided into sterile PET bottles at a ratio of 1:50-1:100, and then sealed after filling.

[0035] Method 2: Pour tea leaves and water into a measuring cup at a ratio of 1:50-1:100, steep cold for 4-12 hours, filter out the tea dregs, and keep the tea soup.

[0036] HPP cold extraction process

[0037] The filled green tea leaves are placed in the high pressure chamber.

[0038] Pressure control: 100-600MPa.

[0039] Holding time: 1 to 10 minutes.

[0040] Temperature control: full-circulation cooling water (5-25℃).

[0041] Pressure transmission medium: water.

[0042] Filter (pure tea)

[0043] First, use a coarse filter (pore size of about 1 to 2 mm) to quickly separate the main body of the tea leaves, and then use multiple layers of filter cloth for secondary filtration to absorb the tiny particles and impurities in the tea soup and retain the tea soup.

[0044] Microfluidizer treatment (optional)

[0045] A micro-jet homogenizer (200-420MPa) is used to efficiently break the cell walls of the tea soup, promote the instantaneous release of intracellular polyphenols, polysaccharides and other components, evenly disperse the fat-soluble functional ingredients in the water phase, and improve the stability of the tea soup.

[0046] HPP sterilization treatment and treatment parameters

[0047] Place green tea in the high-pressure chamber.

[0048] Pressure control: 100-600MPa, equipment pressure fluctuation <±10Mpa.

[0049] Holding time: 1 to 10 minutes.

[0050] Temperature control: Cooling water is circulated throughout the process (5-25°C) to avoid degradation of heat-sensitive substances.

[0051] Pressure transmission medium: water.

[0052] After decompression, transfer to 4°C and refrigerate.

[0053] The finished product is stored and transported in a cold chain at 2-4℃, extending the shelf life to more than 90 days.

[0054] Specific grouping

[0055] Green tea 1 (control group): tea leaves → rinse → bottle and add room temperature purified water.

[0056] Green tea 2 (control group): tea leaves → rinse → bottle and add purified water (boiling water).

[0057] Green Tea 3: Tea leaves → rinse → bottle and add room temperature purified water → HPP extraction → HPP sterilization.

[0058] Green tea 4: frying tea leaves → rinsing → bottling and adding room temperature purified water → HPP extraction → HPP sterilization.

[0059] Green Tea 5: Tea leaves → rinse → add room temperature purified water and cold brew for 4-12 hours → filter → micro-jet homogenization → bottling → HPP sterilization.

[0060] Green Tea 6: Roast the tea leaves → rinse → add room temperature purified water and cold soak for 4 to 12 hours → filter → micro-jet homogenization → bottling → HPP sterilization.

[0061] Green Tea 7: Tea leaves → rinse → bottle and add room temperature purified water → HPP extraction → filter → micro-jet homogenization → bottling → HPP sterilization.

[0062] Green Tea 8: Roasting tea leaves → rinsing → bottling with room temperature purified water → HPP extraction → filtration → microfluidization → bottling → HPP sterilization.

[0063] The samples treated in the above eight ways were tested for colony counts after being refrigerated for 90 days.

[0064] The active ingredients of green tea (including leaf tea soup / pure tea soup) were extracted, and the extraction results are shown in the following table:

[0065]

[0066] Table 1 Table 1 Comparison of extraction rates of active ingredients in green tea (including leaf tea soup / pure tea soup)

[0067]

[0068]

[0069]

[0070] Table 2 Table 2 is a comparison table of sensory qualities of green tea;

[0071] Green tea that had not been sterilized with HPP and green tea that had been sterilized with HPP were subjected to colony detection, and the detection results are shown in Tables 3 and 4 below, respectively:

[0072]

[0073] Table 3

[0074] Table 3 shows the results of colony detection of green tea without HPP sterilization treatment;

[0075]

[0076] Table 4

[0077] Table 4 shows the results of colony detection of green tea after HPP sterilization treatment.

[0078] After the above tests and test results, the following conclusions can be drawn:

[0079] Comparison of active ingredient extraction rates: Compared with traditional extraction, HPP treatment significantly improved the extraction rates of all active ingredients, indicating that its non-thermal processing characteristics are more conducive to ingredient retention. HPP+microfluidization treatment further optimized the extraction effect. Microfluidization homogenization treatment enhanced dissolution efficiency by refining particles, and the extraction rates of most ingredients were close to or exceeded 90%.

[0080] Conclusion of sensory quality comparison

[0081] Breakthrough improvement in color and transparency

[0082] HPP technology avoids high-temperature oxidation, and the tea soup containing leaves is bright green in color (traditional tea soup has obvious browning), and the light transmittance of pure tea soup is >90% (traditional tea soup is darker).

[0083] Micro-jet homogenization makes the tea soup almost crystal clear (transmittance>98%) through nano-level dispersion, and there is no precipitation for a long time.

[0084] Comprehensive improvement of aroma and taste:

[0085] HPP retains volatile substances (ester retention rate >90%), and microfluidization delays aroma dissipation through nanoemulsification (dissipation rate is reduced by 70%).

[0086] Tannin aggregates are broken up by micro-jets (reducing the astringency by 60%), polysaccharide colloids create a lubricating feel, and the taste is optimized from "strong graininess" to "silky and grain-free".

[0087] The tea soup containing leaves does not stratify after being left to stand for 30 days, and the pure tea soup does not precipitate during its shelf life, which is attributed to the Brownian motion of the nanoparticles preventing sedimentation.

[0088] Conclusion of comparison of bactericidal effects:

[0089] HPP sterilization is efficient and thorough, solving microbial hazards;

[0090] Tea drinks that have not been treated with HPP have serious risks of exceeding microbial limits and causing pathogens. In samples that have been sterilized with HPP, the levels of coliform bacteria, mold, yeast, Staphylococcus aureus, etc. were not detected or were below the detection limit, and Salmonella (pathogenic bacteria) was not detected at all, meeting food safety standards. This shows that HPP can completely and efficiently inactivate common microorganisms.

[0091] Advantages of non-thermal sterilization:

[0092] HPP sterilizes without affecting the active ingredients and sensory quality (data in Table 1 and Table 2), overcoming the problems of ingredient loss and flavor deterioration caused by traditional high-temperature sterilization.

[0093] Finally: The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology, characterized in that: The method comprises the following steps: S1. Raw material pretreatment: After washing the tea leaves, the tea leaves and water are divided into sterile PET bottles at a ratio of 1:50-1:100 and sealed after filling. Alternatively, the tea leaves are stir-fried at 80°C-100°C for 5 to 10 minutes and then washed. The tea leaves and water are divided into sterile PET bottles at a ratio of 1:50-1:100 and sealed after filling. S2.HPP cold extraction process: placing the tea leaves in a high-pressure chamber to destroy the cell walls and promote the dissolution of ingredients; S3. Filtration: Filter the tea leaves to remove tea dregs and small particles, retaining the pure tea soup; S4. Microfluidization: Using a microfluidizer, the tea soup is passed through a 50-200 μm pore size channel at a pressure of 200-420 MPa. This utilizes high-speed collisions, shear forces, cavitation, and turbulent vortex dispersion to break down cell walls and disperse fat-soluble components. S5. HPP sterilization treatment: Place the tea soup in a high-pressure chamber at a pressure of 100-600 MPa and a temperature of 5-25°C for 1-10 minutes to destroy the microbial cell membrane and enzyme system to achieve sterilization; S6. Refrigeration of finished products: After sterilization, transfer the tea soup to 4℃ for refrigeration, and store and transport it under the cold chain at 2-4℃.

2. The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology according to claim 1, characterized in that: In the S1 raw material pretreatment, the tea leaves are washed with pure running water for 2 to 10 seconds to remove debris and impurities, and the tea leaves are fried at 80° C. to 100° C. for 5 to 10 minutes to enhance the aroma and pre-sterilize.

3. The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology according to claim 1, characterized in that: The tea beverage in S2 is maintained at a pressure of 100-600 MPa and a temperature of 5-25° C. in the high-pressure chamber for 1-10 minutes, and high-pressure osmosis is used to destroy cell walls and promote the dissolution of components.

4. The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology according to claim 1, characterized in that: The specific method of preparing pure tea soup from tea leaves in S3 is to mix tea leaves with water in a ratio of 1:50-1:100 to prepare tea drink containing leaves, extract the tea with HPP and filter the mixture to obtain pure tea soup.

5. The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology according to claim 1, characterized in that: In S3, the pure tea soup is double filtered through a coarse filter and a multi-layer filter cloth.

6. The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology according to claim 1, characterized in that: In the S4 microfluidizer homogenization process, the tea soup is accelerated to 300-600 m / s in the microfluidizer, and collides at an angle of 60-120 degrees in a Y-shaped, Z-shaped or composite collision chamber, and the number of treatments is 1-3 times.

7. The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology according to claim 1, characterized in that: In the HPP cold extraction process and the HPP sterilization process, the pressure transmission medium is water, and the equipment pressure fluctuation is ≤±10MPa.

8. The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology according to claim 1, characterized in that: It also includes micro-jet homogenization of the tea soup before HPP sterilization to improve the stability of the tea soup and the extraction rate of active ingredients.

9. The non-thermal extraction sterilization method for tea beverages based on HPP and microfluidics technology according to claim 1, characterized in that: In the preparation of the leaf tea beverage, tea leaves are mixed with water and then placed in a sterile PET bottle and sealed. After HPP cold extraction, the complete tea leaves are retained in the bottle.

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