Method for retaining biological activity of raspberry tea freeze-dried powder by utilizing active embedding and modifying technology

Abstract

The invention relates to the technical field of biological component processing, in particular to a method for retaining biological activity of berry tea freeze-dried powder by utilizing an active embedding and modifying technology, which comprises the following steps: respectively treating non-flavone polyphenol, flavone, polysaccharide and amino acid peptide concentrated solutions, adding special components, homogenizing, performing ultrasonic treatment and the like, and performing freeze drying; and compounding the freeze-dried powder according to a specific ratio, and controlling the compounding environment and steps to finally obtain the raspberry tea freeze-dried powder which meets the quality standard and is used in multiple fields. Active substances of the berry tea can be efficiently reserved, the extraction rate is increased, resource waste is reduced, the prepared freeze-dried powder is low in hygroscopicity and good in mobility, the freeze-dried powder is widely applied to the fields of medicine, food and cosmetics, the industrial economy can be improved, and comprehensive benefits can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of biological component processing, and specifically to a method for retaining the biological activity of powdered vine tea by using an active embedding and modification technology. Background Art

[0002] As a medicinal and edible plant, vine tea is rich in active ingredients, which endow it with high nutritional value, health care value and medicinal value, showing broad application prospects in multiple industries. Vine tea is rich in various active ingredients such as flavonoids, polysaccharides, proteins, amino acids and non-flavonoid polyphenols. Among them, the total flavonoid content is as high as 13-42%, which gives it the reputation of "king of flavonoids". These flavonoids include water-soluble and fat-soluble flavonoids, and have various biological activities such as antioxidant, anti-inflammatory and antibacterial. The protein content is 11-15%. It not only contains 17 common amino acids, but also special amino acids such as γ-aminobutyric acid (GABA). It is an important index to measure the tenderness of vine tea. However, its large molecular weight and poor solubility limit the full utilization of functional components. The polysaccharide content is 10-13%, but most of them are insoluble polysaccharides, and the utilization rate of the existing technology is low. The soluble sugar among them is the main component of the aftertaste of vine tea. The non-flavonoid polyphenol accounts for 10-20%. Although it is one of the factors causing the bitter taste of vine tea, it also has unique biological activities.

[0003] However, in actual processing applications, vine tea faces many challenges. In terms of the extraction of active substances, the traditional water extraction method can only extract water-soluble flavonoids, and a large number of other active components are abandoned, resulting in a great waste of resources and an increase in production costs. Moreover, during the extraction process, substances such as flavonoids, non-flavonoid polyphenols, and peptides are extremely susceptible to factors such as temperature, pH, and oxygen, and undergo oxidation, structural changes or degradation, resulting in a significant reduction or even complete loss of biological activity. At the same time, the flavonoid compounds in vine tea have problems of poor water solubility and low bioavailability. At room temperature, the water solubility of free flavonoids is less than 0.1 mg / mL, the dispersion in products is poor, and it is easily degraded by gastric acid, and the intestinal absorption rate is less than 10%. When compounded with other components, the stability is poor, and precipitation is likely to occur or the activity is lost.

[0004] For the insoluble substances in vine tea, such as the conversion and extraction of macromolecular polysaccharides and proteins, there are also difficulties. Most polysaccharides are insoluble substances such as starch and cellulose. Converting them into small molecules to increase solubility, improve the taste and biological activity of tea is the focus of current research, but the existing technology has poor effects in this regard. Vine tea protein contains various functional peptide segments, such as antioxidant peptides and ACE inhibitory peptides, which have the potential for anti-aging and blood pressure lowering. However, traditional processes cannot accurately release these target active peptides, nor can they enrich them directionally, and they cannot solve the problem of the stabilization of active peptides.

[0005] In addition, in terms of retaining biological activity and improving bioavailability, although there are already some technical means, such as green extraction technologies like ultrasonic, microwave, and bio-enzyme extraction, as well as methods like membrane separation and purification and low-temperature drying, they still cannot fully meet the requirements. Although conventional freeze-drying technology can retain a certain amount of biological activity, the formed porous honeycomb structure (porosity greater than 80%) makes the product prone to moisture absorption, leading to problems such as physical deterioration, activity degradation, and microbial contamination. These problems seriously restrict the healthy and efficient development of the deep processing industry of Ampelopsis grossedentata, and it is urgent to develop an innovative Ampelopsis grossedentata processing technology. Summary of the Invention

[0006] (I) Technical Problems to be Solved In view of the deficiencies of the prior art, the present invention provides a method for retaining the biological activity of freeze-dried Ampelopsis grossedentata powder using active embedding and modification technologies.

[0007] (II) Technical Solutions A method for retaining the biological activity of freeze-dried Ampelopsis grossedentata powder using active embedding and modification technologies includes the following steps: Treatment of non-flavonoid polyphenol concentrate: Add trehalose, hydroxypropyl-β-cyclodextrin, L-ascorbyl palmitate, rosmarinic acid, a novel antioxidant, and PLGA to the non-flavonoid polyphenol concentrate; PLGA forms a stable complex with non-flavonoid polyphenols, and the reaction formula of PLGA and chlorogenic acid in non-flavonoid polyphenols is:

[0008] Circulate 3 times under high-pressure homogenization for 10 - 15 min, then perform ultrasonic treatment for 15 - 20 min; then perform freeze-drying; Treatment of flavonoid concentrate: Prepare an oil phase, a surfactant, a co-surfactant, an antioxidant, nano-titanium dioxide quantum dots, and flavonoid-modified gold nanoparticles Au-Flavonoid NPs; heat the oil phase to 50 °C and then add the Ampelopsis grossedentata flavonoid concentrate, stir to dissolve and sequentially add the surfactant, co-surfactant, antioxidant, nano-titanium dioxide quantum dots, and Au-Flavonoid NPs, homogenize for 10 min, and finally perform freeze-drying; Treatment of polysaccharide: Add nano-silica, quaternary ammonium salt of chitosan, and konjac glucomannan to the polysaccharide solution; perform shear emulsification, let it stand, and then perform freeze-drying; after freeze-drying, crush and sieve to make the final moisture content ≤ 1.5% and the porosity ≤ 55%; Treatment of amino acid peptides: Perform freeze-drying on the amino acid peptide solution. Before freeze-drying, add 0.06% of the small molecule antioxidant peptide Gly-Cys-His to the amino acid peptide solution. This antioxidant peptide forms a disulfide bond with the amino acid peptide, and the reaction formula of Gly-Cys-His and glutathione is:

[0009] Compound: 30%-50% freeze-dried flavonoids, 20%-40% freeze-dried non-flavonoid polyphenols, 15%-20% freeze-dried polysaccharides, 8%-15% freeze-dried amino acid peptides; First, dry and cool the polysaccharide powder in an oven; Then mix the peptide / amino acid powder with the flavonoid powder, and then add the non-flavonoid polyphenol powder; Finally, add the polysaccharide powder and mix at high speed, and simultaneously spray in magnesium stearate, and sieve to obtain the freeze-dried powder of Ampelopsis grossedentata.

[0010] Preferably, in the non-flavonoid polyphenol concentrate treatment step, the freeze-drying procedure is: pre-freeze to -45°C, cooling rate 5°C / min, pre-freezing time 2h; In the primary drying stage, the temperature rises from -35°C to -10°C, microwave power 60W, vacuum degree 10Pa, dry for 20-24h; In the secondary drying stage, the temperature is 25°C, vacuum degree 3Pa, dry for 3h, so that the residual water content ≤ 3%.

[0011] Preferably, in the flavonoid concentrate treatment step, a microfluidic chip is used to precisely mix and control the particle size of the mixed solution. The channel width of the microfluidic chip is 50-100μm. By controlling the flow rate ratio of the oil phase: surfactant: co-surfactant and other additive mixtures to be 3:2:1, the particle size distribution of the formed embedding system is more uniform and the stability is higher.

[0012] Preferably, in the shear emulsification process of the polysaccharide treatment step, a variable-frequency ultrasonic-assisted technology is adopted, and the ultrasonic frequency dynamically changes between 20-40kHz, and the power is adaptively adjusted between 100-300W to further optimize the dispersion and structural modification effects of the polysaccharide.

[0013] Preferably, in the amino acid peptide treatment step, the freeze-drying procedure is: pre-freezing temperature ≤ -50°C, cooling rate controlled at 3-7°C / min according to the solution characteristics, pre-freezing time 1-3h; In the primary drying stage, the temperature rises from -40°C to -10°C, vacuum degree 10-20Pa, microwave power 40-60W, dry for 15-20h; In the secondary drying stage, the temperature is 20-30°C, vacuum degree 3-5Pa, dry for 3-5h; The freeze-drying equipment is equipped with a real-time monitoring system, which can online monitor the temperature, pressure, and moisture content during the freeze-drying process, and automatically adjust the heating power and vacuum degree through a feedback control system to ensure the precise control of the freeze-drying process and improve the active retention rate of the amino acid peptide.

[0014] Preferably, in the compounding step, a three-dimensional motion mixer is used as the mixing equipment. The swing amplitude of the mixer is ±30°, and the rotation speed is 30-50r / min, which can achieve all-round uniform mixing of each component and improve the quality stability of the compounded product.

[0015] Preferably, a dry powder product of Ampelopsis grossedentata prepared by the method according to any one of the above.

[0016] Preferably, the application of the dry powder product of Ampelopsis grossedentata according to the previous item in the fields of medicine, food, and cosmetics. In the medical field, it is used to prepare sustained-release capsules for treating cardiovascular diseases, and the content of the dry powder of Ampelopsis grossedentata in the capsules is 300-500 mg per capsule; in the food field, it is used as a raw material for solid beverages, and the addition amount is 10-20 g / 100 g; in the cosmetics field, it is used to prepare antioxidant cream, and the addition amount is 5-10 g / 100 g.

[0017] (III) Beneficial technical effects Compared with the existing technology, the beneficial effects of the present invention are: 1. Through unique active encapsulation and modification technologies, combined with antioxidant synergy and structural densification treatment, the biological activities of various active substances in Ampelopsis grossedentata are greatly retained; in the treatment of non-flavonoid polyphenol concentrate, the added novel antioxidants and biodegradable polymers not only enhance the antioxidant effect but also stabilize non-flavonoid polyphenols through chemical reactions; during the treatment of flavonoid concentrate, the flavonoid-modified gold nanoparticles and titanium dioxide quantum dots introduced significantly improve the stability of flavonoids through electron transfer and photostabilization reactions respectively; during the polysaccharide treatment process, the synergistic effect of konjac glucomannan and polysaccharides improves the structure and properties of polysaccharides, and the small molecule antioxidant peptides added during the amino acid peptide treatment effectively protect the activity of amino acid peptides; after treatment, the retention rate of DPPH free radical scavenging rate of polyphenols and flavonoids in the freeze-dried product is greater than 90%, while that of the traditional process is less than 70%, and the loss rate of key components is only 10%.

[0018] 2. The extraction rate of Ampelopsis grossedentata raw materials is improved, far exceeding the traditional process, realizing zero waste in the whole industrial chain and reducing production costs; from the perspective of driving industrial economy, it is expected that the annual output value of a single production line can reach 200-300 million yuan, which can drive the development of upstream and downstream industrial chains such as planting, processing, and packaging, creating a large number of employment opportunities; at the same time, this technology can be extended to other medicinal and edible homologous plants to help rural revitalization and the development of local characteristic resources.

[0019] 3. In the medical field, it can be directly used to prepare oral tablets and freeze-dried injections; in the food field, due to its good functionality, low hygroscopicity, and good fluidity, it is suitable for making solid beverages and chewable tablets; in the cosmetics field, it can retain natural antioxidant activity and is suitable for dosage forms such as freeze-dried masks and essence liquids to meet the needs of different industries. Description of the drawings

[0020] Figure 1 It is a flow chart of the method for retaining the biological activity of the dry powder of Ampelopsis grossedentata using active encapsulation and modification technology proposed by the present invention; Figure 2It is a bar chart comparing the active ingredient contents of the examples and the comparative examples; Figure 3 It is a radar chart comparing the active ingredient contents of the examples and the comparative examples after unifying the dimensions; Figure 4 It is a comparison chart of the fluidity and hygroscopicity of the examples and the comparative examples; Figure 5 It is the nuclear magnetic resonance spectrum of the product containing a disulfide bond formed by the reaction of Gly-Cys-His with glutathione. Detailed implementation manners

[0021] Example 1 Treatment of non-flavonoid polyphenol concentrate: Accurately measure 1000 mL of non-flavonoid polyphenol concentrate A3, and sequentially add 80 g of trehalose, 50 g of hydroxypropyl-β-cyclodextrin, 1 g of L-ascorbyl palmitate, 0.5 g of rosmarinic acid, 0.3 g of 2,6-di-tert-butyl-4-(N,N-dimethylaminomethyl)phenol, and 0.2 g of poly(lactic-co-glycolic acid) (PLGA); place the mixed solution in a high-pressure homogenizer and circulate it 3 times at a pressure of 100 MPa, with each cycle lasting 5 min, for a total homogenization time of 15 min; then, transfer the homogenized solution to an ultrasonic device and perform ultrasonic treatment for 20 min at a frequency of 25 kHz and a power of 250 W; subsequently, perform freeze-drying, pour the solution into a tray with a thickness controlled at 2 cm; in the pre-freezing stage, cool it to -45 °C at a cooling rate of 5 °C / min and hold for 2 h; during the primary drying, raise the temperature from -35 °C to -10 °C at a heating rate of 0.5 °C / h, simultaneously turn on the microwave power of 60 W, maintain the vacuum degree at 10 Pa, and dry for 24 h; in the secondary drying stage, raise the temperature to 25 °C, adjust the vacuum degree to 3 Pa, and dry for 3 h to make the residual water content ≤ 3%; after drying, take out the freeze-dried product and place it in a desiccator for standby; Treatment of flavonoid concentrate: According to the formula, prepare 500 g of oil phase (375 g of medium-chain triglycerides and 125 g of olive oil derivative), 400 g of surfactant (267 g of food-grade polyoxyl castor oil and 133 g of polysorbate 80), 100 g of co-surfactant (33 g of propylene glycol and 67 g of PEG-400), 5 g of vitamin, 2 g of nano-titanium dioxide quantum dots, and 1 g of flavonoid-modified gold nanoparticles (Au-Flavonoid NPs); heat the oil phase to 50 °C, add 3300 mL of flavonoid concentrate from Ampelopsis grossedentata, and stir until completely dissolved; successively add the surfactant, co-surfactant, vitamin, nano-titanium dioxide quantum dots, and Au-Flavonoid NPs, and homogenize at a speed of 5000 rpm for 10 minutes using a high-speed homogenizer to form a homogenized pre-concentrate B4; after homogenization, stir and react the solution in the dark for 30 min; perform freeze-drying, fill the solution into vials, with 5 mL in each vial; in the pre-freezing stage, cool to -50 °C at a cooling rate of 7 °C / min and hold for 1.5 h; in the primary drying stage, raise the temperature from -40 °C to -5 °C at a heating rate of 1 °C / h, turn on the microwave power of 60 W, maintain the vacuum degree of 15 Pa, and dry for 18 h; in the secondary drying stage, raise the temperature to 30 °C, adjust the vacuum degree to 0.05 Pa, and dry for 10 h, with the glass transition temperature Tg = 68 °C; after drying, seal and store the vials; Treatment of polysaccharide: Take 1000 mL of polysaccharide solution C1, add 8 g of nano-silica, 0.8 g of quaternary ammonium salt of chitosan, and 0.5 g of konjac glucomannan; pour the solution into a shear emulsifier and shear emulsify at a speed of 9000 rpm for 15 minutes; after emulsification, transfer the solution to a refrigeration device and let it stand at 6 °C for 1.5 h; then perform freeze-drying, spread the solution evenly on the freeze-drying tray with a thickness of 1.5 cm; in the pre-freezing stage, pre-freeze at -50 °C for 4 h; in the primary drying stage, raise the temperature from -30 °C to 0 °C at a heating rate of 1 °C / h, maintain the vacuum degree of 10 Pa, turn on the microwave power of 80 W, and dry for 24 h; in the secondary drying stage, raise the temperature to 50 °C, adjust the vacuum degree to 5 Pa, and dry for 6 h; after freeze-drying, crush the product with a crusher and pass through a 120-mesh sieve to make the final moisture content ≤ 1.5% and the porosity ≤ 55%; Treatment of amino acid peptide: Take 1000 mL of amino acid peptide solution, add 0.6 g of small molecule antioxidant peptide (Gly-Cys-His), and stir evenly; pour the solution into a freeze-drying container and perform freeze-drying; in the pre-freezing stage, cool to -50 °C at a cooling rate of 5 °C / min according to the solution characteristics and pre-freeze for 2 h; in the primary drying stage, raise the temperature from -40 °C to -10 °C at a heating rate of 1 °C / h, maintain the vacuum degree of 15 Pa, turn on the microwave power of 50 W, and dry for 18 h; in the secondary drying stage, raise the temperature to 25 °C, adjust the vacuum degree to 4 Pa, and dry for 4 h; Compound preparation: In a clean workshop with humidity ≤ 25% and temperature 18°C, first weigh 15 g of peptide / amino acid powder and 25 g of flavonoid powder, put them into a three-dimensional motion mixer, and mix at a low speed of 200 rpm for 10 min; then add 40 g of non-flavonoid polyphenol powder, adjust the rotation speed to 400 rpm, and mix at a medium speed for 15 min to form a polyphenol-flavonoid complex; weigh 20 g of polysaccharide powder, first dry it in an oven at 55°C for 2.5 h, and then cool it to room temperature in an environment with humidity ≤ 15%; add the pretreated polysaccharide powder to the above complex, and at the same time spray in 0.5 g of magnesium stearate, adjust the rotation speed of the mixer to 600 rpm, and mix at a high speed for 5 min; after mixing, pass through a 60-mesh sieve to obtain the freeze-dried powder of Ampelopsis grossedentata.

[0022] The test results of the prepared freeze-dried powder of Ampelopsis grossedentata show that its non-flavonoid polyphenol content is 38.5 mg / g, the flavonoid content reaches 55.0 mg / g, the polysaccharide content is 12.5 mg / g, and the amino acid peptide content is 9.2 mg / g; the product has excellent physical properties, with a Carr index of 17, indicating good fluidity; it can be completely dissolved in water at 37°C in only 6.5 seconds; the moisture absorption rate at 25°C and relative humidity of 75% for 24 hours is 2.1%, showing good stability; the microbial indicators are excellent, the total number of colonies < 10 CFU / g, and heavy metal lead (Pb) is not detected; these data indicate that the freeze-dried powder has a high content of active ingredients and excellent physical and chemical properties.

[0023] Example 2 Treatment of non-flavonoid polyphenol concentrate: The operation steps are basically the same as those in Example 1, only the high-pressure homogenization time is adjusted to 10 min and the ultrasonic treatment time is adjusted to 15 min, and the addition amounts of other components and the freeze-drying procedure remain unchanged; Treatment of flavonoid concentrate: The proportion of each component in the formula is slightly adjusted. The oil phase accounts for 45% (338 g of medium-chain triglyceride and 112 g of olive oil derivative), the surfactant accounts for 35% (233 g of food-grade polyoxyethylene castor oil and 117 g of polysorbate 80), the co-surfactant accounts for 10% (33 g of propylene glycol and 67 g of PEG-400), the vitamin accounts for 0.8% (8 g), the nano-titanium dioxide quantum dots account for 0.15% (1.5 g), and the flavonoid-modified gold nanoparticles (Au-Flavonoid NPs) account for 0.08% (0.8 g); the homogenization time, the light-shielding reaction time and the freeze-drying procedure are the same as those in Example 1; Treatment of polysaccharide: The proportion of each added component in polysaccharide solution C1 is slightly adjusted, adding 0.6 g of nano-silica, 0.7 g of chitosan quaternary ammonium salt and 0.4 g of konjac glucomannan; the shear emulsification rotation speed is adjusted to 8000 rpm, the emulsification time is 12 minutes, the static temperature is adjusted to 4°C, and the static time is 1 h; in the freeze-drying procedure, the primary drying time is adjusted to 20 h, and other parameters remain unchanged; Amino acid peptide treatment: The pre-freezing cooling rate was adjusted to 4 °C / min, and the primary drying microwave power was adjusted to 40 W. Other operations and parameters were the same as in Example 1; Compound preparation: The compounding ratio was slightly adjusted. The freeze-dried flavonoid powder accounted for 40%, the freeze-dried non-flavonoid polyphenol powder accounted for 30%, the freeze-dried polysaccharide powder accounted for 18%, and the freeze-dried amino acid peptide powder accounted for 12%; The compounding operation and environmental conditions were the same as in Example 1.

[0024] The test results showed that the content of non-flavonoid polyphenols in the prepared freeze-dried moyeam tea powder was 38.3 mg / g, the flavonoid content reached 54.8 mg / g, the polysaccharide content was 12.3 mg / g, and the amino acid peptide content was 9.0 mg / g; The product showed good physical properties: The Carr index was 18, indicating excellent fluidity; It could be completely dissolved in water at 37 °C in only 6.8 seconds; The moisture absorption rate at 25 °C and 75% relative humidity for 24 hours was 2.3%, indicating that the product had good stability; In terms of microbial indicators, the total number of colonies was <10 CFU / g, and heavy metal lead (Pb) was not detected. All indicators met the standard requirements of high-quality freeze-dried powder products.

[0025] Example 3 Non-flavonoid polyphenol concentrate treatment: The high-pressure homogenization time was adjusted to 12 min, the ultrasonic frequency was adjusted to 20 kHz, and the power was adjusted to 200 W. Other operations and component addition amounts were the same as in Example 1; Flavonoid concentrate treatment: In the formula, the oil phase accounted for 55% (413 g of medium-chain triglycerides and 138 g of olive oil derivatives), the surfactant accounted for 40% (267 g of food-grade polyoxyethylene castor oil and 133 g of polysorbate 80), the co-surfactant accounted for 5% (17 g of propylene glycol and 33 g of PEG-400), the vitamin accounted for 1% (10 g), the nano-titanium dioxide quantum dots accounted for 0.25% (2.5 g), and the flavonoid-modified gold nanoparticles (Au-Flavonoid NPs) accounted for 0.12% (1.2 g); The homogenization time, light-shielding reaction time, and freeze-drying procedure were the same as in Example 1; Polysaccharide treatment: The proportion of each added component in polysaccharide solution C1 was slightly adjusted, adding 1 g of nano-silica, 0.9 g of chitosan quaternary ammonium salt, and 0.6 g of konjac glucomannan; The shear emulsification speed was adjusted to 10000 rpm, the emulsification time was 10 minutes, the static temperature was adjusted to 8 °C, and the static time was 2 h; In the freeze-drying procedure, the secondary drying time was adjusted to 4 h, and other parameters remained unchanged; Amino acid peptide treatment: The pre-freezing cooling rate was adjusted to 6 °C / min, and the primary drying vacuum degree was adjusted to 20 Pa. Other operations and parameters were the same as in Example 1; Compound blending: Fine-tune the compounding ratio. The freeze-dried flavonoids account for 45%, the freeze-dried non-flavonoid polyphenols account for 35%, the freeze-dried polysaccharides account for 16%, and the freeze-dried amino acid peptides account for 14%. The compounding operation and environmental conditions are the same as those in Example 1.

[0026] After testing, the contents of the main active ingredients of this freeze-dried moye jiaogulan are as follows: non-flavonoid polyphenols 38.8 mg / g, flavonoids 55.5 mg / g, polysaccharides 12.7 mg / g, and amino acid peptides 9.4 mg / g. The product has excellent physical performance: The Carr index of 16 indicates excellent fluidity; it can be completely dissolved in water at 37°C in only 6.2 seconds, showing good instant solubility; the moisture absorption rate at 25°C and 75% relative humidity for 24 hours is only 2.0%, showing excellent moisture-proof performance; in terms of microbial indicators, the total number of colonies < 10 CFU / g, and heavy metal lead (Pb) is not detected. All indicators meet the standard requirements of high-quality freeze-dried powder, fully reflecting the high content of active ingredients and excellent stability of the product.

[0027] Control example Treatment of non-flavonoid polyphenol concentrate: Only add 8% trehalose, 5% hydroxypropyl-β-cyclodextrin, 0.1% L-ascorbyl palmitate, 0.05% rosmarinic acid, without adding 2,6-di-tert-butyl-4-(N,N-dimethylaminomethyl)phenol (DBADMP) and poly(lactic-co-glycolic acid) (PLGA); High-pressure homogenization is circulated 2 times at a pressure of 80 MPa for 10 min, without ultrasonic treatment; Freeze-drying uses a conventional freeze-drying procedure, with a pre-freezing temperature of -30°C and a pre-freezing time of 1 h; The primary drying temperature is -20°C, the vacuum degree is 20 Pa, and the drying time is 15 h; The secondary drying temperature is 30°C, the vacuum degree is 5 Pa, and the drying time is 3 h; Treatment of flavonoid concentrate: Using the traditional embedding method, only embedding with a single surfactant polysorbate 80, without adding nano-titanium dioxide quantum dots and flavonoid-modified gold nanoparticles (Au-Flavonoid NPs); Freeze-drying uses a conventional freeze-drying procedure, with a pre-freezing temperature of -40°C and a pre-freezing time of 1.5 h; The primary drying temperature is -30°C, the vacuum degree is 25 Pa, and the drying time is 18 h; The secondary drying temperature is 35°C, the vacuum degree is 8 Pa, and the drying time is 5 h; Treatment of polysaccharides: Only add 0.5% nano-silica, without adding quaternary ammonium salt of chitosan and konjac glucomannan; The shear emulsification speed is 6000 rpm, the emulsification time is 8 minutes, without standing treatment; Freeze-drying uses a conventional freeze-drying procedure, with a pre-freezing temperature of -45°C and a pre-freezing time of 3 h; The primary drying temperature is -25°C, the vacuum degree is 15 Pa, and the drying time is 20 h; The secondary drying temperature is 40°C, the vacuum degree is 6 Pa, and the drying time is 5 h; Amino acid peptide treatment: Do not add small molecule antioxidant peptide (Gly-Cys-His); Freeze-drying adopts the conventional freeze-drying procedure, with a pre-freezing temperature of -40°C and a pre-freezing time of 2 h; The primary drying temperature is -30°C, the vacuum degree is 20 Pa, and the drying time is 18 h; The secondary drying temperature is 30°C, the vacuum degree is 5 Pa, and the drying time is 4 h; Compound preparation: Conduct compound preparation under ordinary environment (humidity 40%, temperature 25°C), and the compounding ratio is arbitrarily set as 20% of flavonoid freeze-dried powder, 30% of non-flavonoid polyphenol freeze-dried powder, 25% of polysaccharide freeze-dried powder, and 25% of amino acid peptide freeze-dried powder; During mixing, use a simple stirring method, do not use a three-dimensional motion mixer, do not spray magnesium stearate, and do not screen.

[0028] The test results show that in the freeze-dried powder of this moye tea, the content of non-flavonoid polyphenols is 35.0 mg / g, the flavonoid content is 45.0 mg / g, the polysaccharide content is 10.0 mg / g, and the amino acid peptide content is 8.0 mg / g; In terms of the physical properties of the product, the Carr index is 25, indicating general fluidity; The dissolution time in water at 37°C is 12.0 seconds, and the dissolution performance needs to be improved; The moisture absorption rate at 25°C and 75% relative humidity for 24 hours is 5.0%, and the moisture-proof performance needs to be further improved; In terms of hygiene indicators, the total number of colonies is 50 CFU / g. Although heavy metal lead (Pb) is not detected, some other hygiene indicators exceed the standard limits.

[0029] Comparison table of the active ingredient contents of the examples and the comparative examples: Conclusion: This table shows the active ingredient contents of the freeze-dried powder of moye tea in the examples and the comparative examples. The contents of non-flavonoid polyphenols, flavonoids, polysaccharides and amino acid peptides in the examples are all higher than those in the comparative examples, indicating that the preparation method of the present invention can more effectively retain and enrich the active ingredients in moye tea.

[0030] Comparison table of the product performances of the examples and the comparative examples: Conclusion: This table compares the fluidity, dissolution time, hygroscopicity and total number of colonies of the products in the examples and the comparative examples. The examples show better performance in terms of fluidity, dissolution time and hygroscopicity, and the total number of colonies is also much lower than that in the comparative examples, indicating that the freeze-dried powder of moye tea prepared by the present invention has more advantages in product performance and hygiene quality.

[0031] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirits of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preserving biological activity of freeze-dried berry tea powder using active encapsulation and modification technology, characterized in that: The following steps are involved: Treatment of berry tea non-flavonoid polyphenol concentrate: trehalose, hydroxypropyl-β-cyclodextrin, L-ascorbyl palmitate, rosmarinic acid, a new antioxidant and PLGA were added to the non-flavonoid polyphenol concentrate; PLGA and non-flavonoid polyphenols formed a stable complex, wherein the reaction formula of PLGA and non-flavonoid polyphenol chlorogenic acid was:

2. Cycle 3 times of high pressure homogenization for 10-15 min, then ultrasonic treatment for 15-20 min; then freeze-drying; Treatment of berry tea flavonoid concentrate: prepare oil phase, surfactant, co-surfactant, antioxidant, nano-titanium dioxide quantum dots and flavonoid modified gold nanoparticles Au-Flavonoid NPs; heat the oil phase to 50°C and add berry tea flavonoid concentrate, stir and dissolve, add surfactant, co-surfactant, antioxidant, nano-titanium dioxide quantum dots and Au-Flavonoid NPs in sequence, homogenize for 10 minutes, and finally freeze-dry; Treatment of berry tea polysaccharide: adding nano-silicon dioxide, chitosan quaternary ammonium salt and konjac glucomannan to the polysaccharide solution; emulsifying by shearing, standing, and then freeze-drying; crushing and sieving after freeze-drying to make the final moisture content ≤1.5% and the porosity ≤55%; Berry tea amino acid peptide treatment: The amino acid peptide solution was freeze-dried. Before freeze-drying, 0.06% of the small molecule antioxidant peptide Gly-Cys-His was added to the amino acid peptide solution. The antioxidant peptide formed a disulfide bond with the amino acid peptide, and the reaction formula of Gly-Cys-His and glutathione was:

3. Compounding: 30%-50% flavonoid freeze-dried powder, 20%-40% non-flavonoid polyphenol freeze-dried powder, 15%-20% polysaccharide freeze-dried powder, 8%-15% amino acid peptide freeze-dried powder; first dry and cool the polysaccharide powder in an oven; then mix the peptide / amino acid powder with the flavonoid powder, and then add the non-flavonoid polyphenol powder; finally, add the polysaccharide powder and mix at high speed, and simultaneously spray magnesium stearate, and sieve to obtain the berry tea freeze-dried powder.

4. The method for retaining biological activity of freeze-dried berry tea powder using active encapsulation and modification technology according to claim 1, characterized in that: In the non-flavonoid polyphenol concentrate processing step, the freeze-drying procedure is: pre-freezing to -45°C, cooling rate 5°C / min, pre-freezing time 2h; in the primary drying stage, the temperature is raised from -35°C to -10°C, microwave power 60W, vacuum degree 10Pa, and drying for 20-24h; In the secondary drying stage, the temperature is 25°C, the vacuum degree is 3Pa, and the drying time is 3h to make the residual water content ≤3%.

5. The method for retaining biological activity of freeze-dried berry tea powder using active encapsulation and modification technology according to claim 1, characterized in that: In the flavonoid concentrate processing step, a microfluidic chip is used to accurately mix the mixed solution and control the particle size. The channel width of the microfluidic chip is 50-100 μm. By controlling the flow rate ratio of the oil phase: surfactant: co-surfactant and other additives mixed solution to 3:2:1, the particle size distribution of the formed encapsulation system is more uniform and the stability is higher.

6. The method for retaining biological activity of freeze-dried berry tea powder using active encapsulation and modification technology according to claim 1, characterized in that: During the shear emulsification process of the polysaccharide treatment step, variable frequency ultrasonic assisted technology was used. The ultrasonic frequency changed dynamically between 20-40kHz and the power was adaptively adjusted between 100-300W to further optimize the dispersion and structural modification effects of the polysaccharides.

7. The method for retaining biological activity of freeze-dried berry tea powder using active encapsulation and modification technology according to claim 1, characterized in that: In the amino acid peptide processing step, the freeze-drying procedure is: pre-freezing temperature ≤ -50 ° C, cooling rate is controlled at 3-7 ° C / min according to the solution characteristics, and pre-freezing time is 1-3 hours; in the primary drying stage, the temperature is increased from -40 ° C to -10 ° C, the vacuum degree is 10-20 Pa, the microwave power is 40-60 W, and the drying time is 15-20 hours; In the secondary drying stage, the temperature is 20-30℃, the vacuum degree is 3-5Pa, and the drying time is 3-5h. The freeze-drying equipment is equipped with a real-time monitoring system, which can monitor the temperature, pressure, and moisture content during the freeze-drying process online, and automatically adjust the heating power and vacuum degree through the feedback control system to ensure precise control of the freeze-drying process and improve the activity retention rate of amino acid peptides.

8. The method for retaining biological activity of freeze-dried berry tea powder using active encapsulation and modification technology according to claim 1, characterized in that: In the compounding step, the mixing equipment uses a three-dimensional motion mixer with a swing amplitude of ±30° and a rotation speed of 30-50r / min, which can achieve all-round and uniform mixing of the components and improve the quality stability of the compounded product.

9. A freeze-dried berry tea powder product prepared by the method according to any one of claims 1 to 6.

10. The application of the freeze-dried berry tea powder product of claim 7 in the fields of medicine, food and cosmetics, characterized in that: In the pharmaceutical field, it is used to prepare sustained-release capsules for the treatment of cardiovascular diseases, and the content of berry tea freeze-dried powder in the capsules is 300-500 mg / capsule; in the food field, it is used as a raw material for solid beverages, and the added amount is 10-20g / 100g; in the cosmetics field, it is used to prepare antioxidant creams, and the added amount is 5-10g / 100g.

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