32 results about "Theaflavin" patented technology

The invention discloses yellow tea with high stability of theaflavin as well as a preparation method and application thereof, and the yellow tea with high stability of theaflavin is obtained through enhanced fermentation and green leaf rocking treatment and by utilizing a steam explosion technology. A proper amount of yellow tea is taken and smashed, clear extract liquor is obtained through an ultrasonic extraction technology and a nanofiltration technology, the extract liquor and white spirit are mixed in proportion to form the tea wine, high performance liquid chromatography is used for determination, theaflavin is increased by 2.2 times, and stability of theaflavin in the yellow tea wine is determined to be improved through a stability experiment. The content and stability of theaflavin in the yellow tea are improved through enhanced fermentation, rocking and steam explosion treatment, the tea wine is rich in flavor level and golden yellow and transparent in color through the nanofiltration technology and the optimal proportion, the unique flavor and nutritional value of the yellow tea can be effectively improved, and the tea wine has better sensory quality and high health-care value.

The invention provides high-activity crataegus pinnatifida fruit vinegar and a preparation method thereof.The preparation method comprises the steps that crataegus pinnatifida fruits are juiced, then a composite chelating agent composed of polyglucuronic acid and monopotassium phosphate is added for chelating treatment, and a polysaccharide-metal ion cross-linked network is removed; then adding endo-beta-1, 4-glucanase to carry out linear polysaccharide directional enzymolysis, so that the viscosity of the fruit juice is obviously reduced; after the components are adjusted, double modified yeast beta-glucan microspheres are added, yeast is inoculated for alcoholic fermentation, the microspheres are subjected to double grafting modification through galactooligosaccharide and theaflavin, and active components in the crabapple can be directionally captured and stabilized through hydrophilic and hydrophobic effects respectively; after alcohol fermentation is finished, acetic bacteria are inoculated for acetic fermentation, and finally, filtering and sterilization are performed. According to the method disclosed by the invention, by virtue of a synergistic strategy of breaking a network firstly, then carrying out enzymolysis debonding and then carrying out microsphere loading, the fermentation mass transfer efficiency is effectively improved, and meanwhile, the retention rate of functional components such as polyphenol and saponin in the fruit vinegar is increased.

The invention discloses a preparation method and application of a hippophae rhamnoides fruit tea fermentation product, and the preparation method comprises the following steps: firstly preparing a hippophae rhamnoides fruit tea leachate according to a solid-liquid ratio of 1: 20-1: 100, then inoculating aspergillus cristatus according to an inoculum size of 1.5%-3.5%, fermenting for 3-12 days, and finally centrifuging and drying to obtain the hippophae rhamnoides fruit tea fermentation product. According to the method, the optimal material-liquid ratio, the inoculation amount and the fermentation time for preparing the hippophae rhamnoides fruit tea fermentation product are determined through the single factor level, the enzymatic activity of amylase, pectinase, protease and the like in the hippophae rhamnoides fruit tea fermentation product is remarkably improved, the protease activity is improved by 10 times or above, and digestion and absorption of macromolecular nutrient substances in the hippophae rhamnoides fruit tea are facilitated; the content of theabrownin in a sea-buckthorn tea fermented product is remarkably increased, the flavor and the physiological activity of the product are improved, a functional sea-buckthorn product rich in theabrownin is provided, and high-value utilization of sea-buckthorn resources is promoted; and harmful mycotoxins such as aflatoxin B1 are not detected, so that the safety is high.

The invention relates to the technical field of tea processing, in particular to a black tea fermentation regulation and control method and equipment based on a multienzyme synergistic effect, and the method comprises the following steps: S1, mixing enzymes such as polyphenol oxidase and peroxidase, adding trehalose, trisodium citrate and vitamin C, fixing the volume with a phosphate buffer solution, and activating in a water bath at 30 DEG C to obtain a compound enzyme solution; s2, withering the fresh leaves until the water content is 60-65%, performing UV-C intermittent irradiation, and performing gradient rolling to obtain rolled leaves; s3, spraying enzyme liquid which accounts for 1.5-2.0% of the weight of the rolled leaves, and performing ultrasonic-assisted permeation; s4, performing three-stage temperature-controlled fermentation, stirring every 30 minutes, introducing ozone air, and adding a pulsed magnetic field every hour; s5, detecting the conversion rate of tea polyphenol, theaflavin and the like, and terminating fermentation after reaching the standard; s6, performing microwave fixation after hot air treatment; and S7, drying in sections until the water content is 5-6% to obtain a finished product. According to the method, the tea polyphenol conversion efficiency and theaflavin generation balance of the black tea are improved, aroma substances are reserved, and the functional activity is enhanced; the process stability is optimized, the energy consumption and pollution are reduced, and the black tea quality and industrial benefits are improved.

The invention belongs to the field of biological medicine, and particularly relates to application of Thaflavanin-3 '-Gallate or NAD < + > in preparation of a product for preventing or treating monkey pox virus infection. The invention finds that the protein OPG188 of the monkey pox virus can significantly inhibit the natural immune process of the monkey pox virus, compounds Thaflavanin-3 '-Gallate and NAD + which have the highest affinity with the OPG188 are screened out through molecular virtual docking, and the action effects of the compounds are verified through cell experiments and molecular experiments, which indicates that the Thaflavanin-3'-Gallate and NAD + have the effect of inhibiting the replication of the monkey pox virus. The compound can be used for preparing medicines for resisting monkey pox virus infection.

This invention relates to the field of tea quality improvement and processing technology, and discloses a processing method for enhancing the freshness, reducing astringency, and increasing aroma of tea using bio-enzymes. The steps include: fresh leaf picking, controlled-light intermittent withering, bio-enzyme spraying withering, controlled-frequency rolling, variable-temperature and humidity controlled fermentation + bio-enzyme spraying, high-temperature short-time hot air finishing, and far-infrared radiation finishing. The bio-enzymes used in the bio-enzyme spraying withering and variable-temperature and humidity controlled fermentation + bio-enzyme spraying steps are biomimetic enzymes, precisely formulated according to the types and activities of bio-enzymes found in the intestines of insects that feed on fresh tea leaves. Through the synergistic effects of bio-enzyme spraying, precise control of specific light, and far-infrared radiation finishing, the method promotes the formation and enrichment of sweet and savory substances such as amino acids, soluble sugars, and theaflavins, as well as aromatic substances such as alcohols, aldehydes, ketones, and esters. The processing method of this invention can achieve targeted enhancement of freshness, reduction of astringency, and increase of aroma in tea, enabling the stable and high-quality production of characteristic flavored teas, improving the industrial value of bulk tea and summer and autumn teas, and promoting quality improvement and efficiency enhancement.

The application discloses a kind of for anti-aging regulation blood fat blood sugar, the purification method of high-purity tea pigment of uric acid.It is with summer and autumn tea crude leaf, tea residue as raw material, by enzyme directed conversion, double-frequency ultrasonic subcritical water extraction, three-stage membrane separation, molecularly imprinted resin precision purification, the integrated innovative process of low-temperature freeze drying, prepare high-purity tea pigment with total purity ≥95%, the flavan-3-ols ≥35%, active retention rate ≥95%, realize the safety standard of no solvent residue, low caffeine, desalination and heavy metal removal.The high-purity tea pigment has four synergistic effects of strong antioxidant anti-aging, protecting blood vessels and improving circulation, regulating blood sugar, inhibiting uric acid generation and promoting excretion, and can be widely applied to functional food, health food, pharmaceutical intermediates and special medical food.The application has advanced process, green environmental protection, high raw material utilization rate and batch stability, solves the technical bottleneck of low purity, poor activity and insufficient safety of traditional tea pigment, and has significant innovation, practicality and industrialization value.

This invention discloses a *Aspergillus ryukyu* strain and its applications. The *Aspergillus ryukyu* strain is named *Aspergillus ryukyu* P001, with accession number CGMCC NO.42119, deposited on July 3, 2025, at the China General Microbiological Culture Collection Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China. The *Aspergillus ryukyu* strain provided by this invention can efficiently secrete catechol 1,2-dioxygenase, significantly improving the degradation efficiency of phenolic substances. When the strain provided by this invention or its produced catechol 1,2-dioxygenase ferments tea (such as ripe Pu-erh tea), it can accelerate the degradation of tea polyphenols, catechins, and other substances, promote the formation of theaflavins, resulting in a reddish-brown tea liquor with a mellow taste and a shortened fermentation cycle.

The application belongs to the technical field of food processing and biological medicine, and particularly relates to a quaternary ammonium cellulose / pectin / teaflavin compound and a preparation method and application thereof. The quaternary ammonium cellulose / pectin / teaflavin compound takes quaternary ammonium cellulose and pectin as wall materials, and teaflavin as a loaded drug, and the three are self-assembled. Experimental results show that the obtained composite system has high encapsulation efficiency and loading capacity for teaflavin, the constructed quaternary ammonium cellulose / pectin / teaflavin compound has strong antioxidant performance and pH responsiveness, the strong antioxidant capacity effectively protects teaflavin from oxidative damage during delivery, and maintains the biological activity thereof; the pH responsiveness enables the compound to realize more efficient release of teaflavin in an acidic environment such as a tumor tissue or an inflammation site, thereby improving the targeting and treatment effect. Moreover, the preparation method of the compound is simple and has good repeatability, and is expected to provide a new reference method for the development of a drug delivery system.

The invention discloses an extraction method of theaflavin-3, 3 '-digallate and application of theaflavin-3, 3'-digallate in preparation of microcapsules and duck meat emulsion sausages, and is characterized in that a theaflavin crude product is added into an acetone solution, separation is performed through Sephadex LH-20 gel chromatographic column chromatography, the acetone solution is used as an eluent for gradient elution, an elution component is collected, and the theaflavin-3, 3 '-digallate is obtained. The preparation method comprises the following steps: dissolving theaflavin-3, 3 '-digallate in water to obtain theaflavin-3, 3'-digallate, further mixing a maltodextrin solution, an Arabic gum solution and a beta-cyclodextrin solution, adding the mixture into the theaflavin-3, 3 '-digallate solution to obtain a mixed solution, stirring, and freeze-drying to obtain the theaflavin-3, 3'-digallate microcapsule. The invention further provides application of the microcapsule in preparation of the duck meat emulsified sausage, and the microcapsule has the advantages that the lipid oxidation effect is remarkably inhibited, the flavor stability and slow release property of the duck meat emulsified sausage are improved, and the functional action time of the duck meat emulsified sausage is prolonged.

The invention belongs to the technical field of tea leaf processing, and provides a fermentation process for regulating and controlling the content of theaflavin in black tea, which comprises the following steps: fermenting withered and rolled tea leaves; fermenting for 40 to 80 minutes under the conditions that the temperature is 28 to 32 DEG C and the relative humidity is 90 to 95 percent; fermenting for 60 to 120 minutes under the conditions that the temperature is 24 to 26 DEG C and the relative humidity is 85 to 90 percent; fermenting for 20 to 40 minutes under the conditions that the temperature is 20 to 22 DEG C and the relative humidity is 80 to 85 percent; in the first stage and the second stage, oxygen-enriched air is intermittently introduced into the fermentation environment, so that the oxygen concentration is maintained at 23%-25%. According to the method disclosed by the invention, the generation and accumulation of theaflavin can be accurately regulated and controlled through the cooperation of multi-stage temperature change and dynamic oxygenation, the problems of unstable theaflavin content and large quality fluctuation of a traditional fermentation process are effectively solved, and the prepared black tea is high in theaflavin content, bright in liquor color, fresh and refreshing in taste and stable in quality and can be directionally regulated and controlled.

The invention provides a meat pre-prepared vegetable flavor retention agent and a preparation method thereof. The meat pre-prepared vegetable flavor retention agent comprises a thermal reaction covering base, a vinasse re-fermentation product, a spice extract, a preservative and a rancidity inhibitor, the thermal reaction covering fragrance base is prepared by performing Maillard reaction on raw materials including xylose, glucose, glycine, alanine, proline, lysine, a yeast extract, an HVP raw material, soybean oil, corn fermented sauce, citric acid, edible salt and white granulated sugar, then adding maltodextrin and performing spray drying; the vinasse re-fermentation product is obtained by adding water into yellow rice wine lees, crushing the yellow rice wine lees into liquid through a colloid mill, performing full fermentation, and then performing spray drying on the feed liquid; the spice extract is prepared by uniformly mixing a liquorice extract, a radix angelicae extract and a coriander seed extract; the preservative is thymol; the rancidity inhibitor is a composition of tea polyphenol and theaflavin. The flavor retention agent disclosed by the invention can fully reduce peculiar smell generated in the storage and reheating processes of the prefabricated dishes.

The invention relates to a processing technology for improving tea quality. Precise control is performed from the beginning of tea leaf picking, rapid transfer of the unmanned aerial vehicle is utilized, damage, oxidation and other conditions of tea leaves are avoided, the consistency of raw materials is improved, through cooperation of the solar heat pump system and the near-infrared spectrometer, the tea leaf withering time is effectively shortened, the tea leaf water content is controlled, and the tea leaf withering quality is improved through combined treatment of microwaves and hot air. Uniform fixation of the tea leaves is realized, the fixation effect is improved, crushed materials of tea leaf cells are accurately controlled through staged pressurized rolling of an air pressure rolling machine, uniform seepage of tea leaf juice is ensured, and in the fermentation process, the temperature and humidity are accurately regulated and controlled, the fermentation time is controlled, and the generation condition of aroma substances is monitored by using an electronic nose; the content of components such as theaflavin is increased, and the retention rate of aroma components is increased by utilizing far infrared drying and vacuum freeze drying technologies. According to the technology, through multi-link accurate control, the quality of the tea leaves is effectively improved.

This invention provides a composition for targeted blood sugar regulation aided by *Dictyophora indica* polysaccharide, its preparation method, and its application, belonging to the technical field of edible fungus extracted polysaccharide health food. The composition of this invention comprises 4-6 parts of *Dictyophora indica* polysaccharide, 1-2 parts of *Sandoan*, 1-3 parts of theaflavins, 18-22 parts of 7-day intestinal health supplement, and 5-7 parts of freeze-dried *Tremella fuciformis* powder. The composition of this invention has a significant blood sugar lowering effect in prediabetes, and the raw materials are readily available, allowing for long-term use without toxic side effects.

A method for producing theasinensin A by a low-temperature enzymatic method is disclosed. Using a plant polyphenol oxidase enzyme extract or polyphenol oxidase enzyme preparation as the enzyme source, epigallocatechin gallate (EGCG) as the substrate, and a buffer solution with a specific pH value as the reaction system, theasinensin A (TSA) is synthesized by a directed enzymatic reaction through steps such as low-temperature enzymatic reaction and subsequent column chromatography, distillation concentration, liquid phase preparation, and freeze-drying. This method enables enzymatic oxidation of EGCG at low temperatures and yields dimerized TSA via a conversion reaction, establishing a theoretical and practical foundation for environmentally friendly, safe, efficient, and large-scale industrial production and utilization of TSA.

The invention relates to a black tea withering treatment process. Fresh leaves are selected and naturally withered to reduce the water content, then liquid nitrogen freezing treatment is performed, leaf tissue cell sap is frozen at low temperature, cells are burst to change the permeability of cell membranes, polyphenol compounds in unfrozen cells synchronously and rapidly make contact with polyphenol oxidase, an enzymatic oxidation reaction is generated, and then the tea polyphenol content is reduced; the content of theaflavin is increased. Under normal pressure, the temperature of the liquid nitrogen is-196 DEG C, so that cells can be quickly and completely frozen when the tea leaves are frozen by the liquid nitrogen, the cells are damaged more synchronously and efficiently after unfreezing, the cell damage rate of the leaves is increased, and the enzymatic oxidation reaction of polyphenols is promoted. The content of theaflavin in the black tea obtained by the process is obviously increased, and the tea leaves are improved in the aspects of appearance, aroma, liquor color, taste, leaf bottom quality and the like.

The invention discloses a method for synthesizing theaflavin by taking lotus root as a raw material, which belongs to the field of natural product pigment synthesis and comprises the following steps: raw material collection, slicing, browning reaction, vacuum drying and theaflavin extraction and purification. The lotus root theaflavin extract prepared in a browning mode has a remarkable, mild and lasting coloring effect on hair, especially white hair, and can cover a wide range of color systems including but not limited to various natural hair colors such as light brown, chestnut color, brown color and dark brown. The method for synthesizing the theaflavin by taking the lotus root as the raw material is expected to break through the dependence on tea leaves or expensive monomers, and opens up a new way for large-scale and commercial production of the theaflavin.

This invention discloses a co-production process for instant black tea and ultrafine black tea powder. Using fresh tea leaves as raw material, after appropriate withering, the leaves are pulverized to a fineness of 10-40 mesh. First, solid-state fermentation is carried out at 30-40℃, followed by liquid-state fermentation at 30-40℃ at a material-to-liquid ratio of 1:5-20. After fermentation, the tea is first ultrasonically extracted, then microwave extracted. After extraction, the tea is centrifuged, and the supernatant is transferred to a vacuum concentrator or membrane filtration device for concentration. Finally, the concentrated liquid is freeze-dried or spray-dried to obtain instant black tea with a theaflavins content greater than 3.0%. The components in the extract, excluding the supernatant, are dried, sieved, and ultrafinely pulverized to obtain ultrafine black tea powder rich in dietary fiber and protein. This process has a short production cycle, saves energy, and produces few byproducts, providing technical support for the green preparation of deep-processed tea.

This invention belongs to the field of tea processing technology. It provides a novel comprehensive processing technique for improving the quality of summer and autumn black tea, comprising the steps of gentle shaking combined with UV-B-LED combined spectral withering, low-temperature controlled pressure gradient kneading, three-parameter linked dynamic fermentation, microwave-hot air coupled drying, and far-infrared variable-temperature aroma enhancement. Gentle shaking combined with UV-B-LED combined spectroscopy promotes the polymerization and transformation of flavor components; low-temperature controlled pressure gradient kneading allows for controllable cell breakage of tea leaves, promoting the outflow of tea juice; three-parameter linked dynamic fermentation increases the content of theaflavins and aromatic substances, improving the uniformity of fermentation; microwave-hot air coupled drying reduces aroma loss and improves drying efficiency; far-infrared variable-temperature aroma enhancement enriches the aroma of the tea, improves tea quality, and enhances the harmony and lasting sweetness of the tea soup. The resulting black tea has a complex aroma of flowers and honey, a bright red liquor, a mellow and refreshing taste, and a comprehensive sensory score as high as 95.6.

The invention discloses a processing method of black tea in the field of tea processing. According to the method, a specially-made mesoporous silica-zeolite molecular sieve core-shell structure loaded nano metal oxide composite material is added in the tea rolling stage, and the fermentation process is cooperatively regulated and controlled. The material is prepared by carrying out amino functionalization on a zeolite molecular sieve, adsorbing cerium and yttrium metal ions under a specific pH value condition, synchronously constructing a mesoporous silica shell layer, and carrying out solvothermal crystallization and gradient calcination, and has a fine core-shell structure and high-dispersion catalytic active sites. The black tea processing comprises the steps of withering, catalytic rolling and pre-fermentation, main fermentation and catalyst magnetic separation and drying. According to the method, by utilizing the shape-selective catalysis and oxidation functions of the composite material, the generation of theaflavin can be directionally promoted, the aroma is optimized, the fermentation time is remarkably shortened, the quality stability and the production efficiency of black tea are improved, and the catalyst can be recycled.

The application discloses a method for rapidly detecting 30 compounds in tea, such as catechins, flavonoids, anthocyanins, phenolic acids and amino acids, wherein the 30 compounds are gallic acid, theobromine, GC, protocatechuic acid, theophylline, EGC, theanine, chlorogenic acid, caffeine, catechin, syringic acid, caffeic acid, vanillic acid, epicatechin, EGCG, delphinidin, salicylic acid, GCG, p-coumaric acid, cyanidin, ferulic acid, sinapic acid, rutin, ECG, pelargonidin, myricetin, theaflavin, quercetin, apigenin and kaempferol. The application can realize simultaneous rapid qualitative and quantitative detection of the 30 compounds, and provides technical support for development of active substances in tea.

The invention discloses a method for increasing the content of theaflavin in tea leaves, and belongs to the technical field of tea leaf processing. The method specifically comprises the following steps: (1) selecting tea leaves which are stout in bud leaves, light green in color and luster and free of plant diseases, insect pests and mechanical damage for later use; (2) stir-frying the tea leaves by adopting a stir-frying process; (3) quickly taking the stir-fried tea leaves out of the pot, immediately putting the tea leaves into a food-grade plastic bag, quickly sealing the bag, and then putting the bag into a hemp cloth bag; (4) performing secondary fermentation on the tea leaves in the hemp cloth bag by utilizing the residual heat of the fried tea leaves; and (5) after the secondary fermentation is finished, taking out the tea leaves, drying, screening and packaging to obtain the finished tea leaves. The method can effectively improve the content of theaflavin in the tea leaves, is simple and convenient to operate and low in cost, and keeps other qualities of the tea leaves, so that the overall quality of the tea leaves is improved.

The invention discloses a preparation method of theaflavin self-assembly nanoparticles and application of the theaflavin self-assembly nanoparticles in hair loss prevention. The preparation method of the theaflavin self-assembly nanoparticles comprises the following steps: (1) soaking tea tree branches and leaves in water, adding laccase to carry out enzymatic oxidation reaction, and after the reaction, carrying out filtration concentration and chloroform and ethyl acetate extraction to obtain theaflavin; and (2) dissolving theaflavin and L-cysteine in water, and dropwise adding a formaldehyde solution for reaction to obtain the theaflavin self-assembled nanoparticles. The prepared self-assembled nanoparticles are rich in sulfydryl groups, can target hair follicles and stimulate hair growth, are rich in amino groups, carboxyl groups and phenolic hydroxyl groups, can be combined with hyaluronidase and 5 alpha-reductase, and have the effects of preventing androgenetic alopecia and improving scalp sensitivity.

This invention relates to the field of functional beverages and traditional Chinese medicine health products, and discloses a highly effective medicinal and edible plant-based beverage for treating bitter taste and halitosis, as well as its preparation process. The optimal formula of the raw materials for the plant-based beverage is as follows: 10 grams of dandelion; 10 grams of purslane; 3 grams of black tea; 20 grams of Poria cocos; and 20 grams of apple. Among them, dandelion is the core ingredient for clearing heat and removing dampness, directly clearing liver and stomach heat to treat the root cause of bitter taste; purslane has antibacterial and anti-inflammatory properties, targeting and inhibiting harmful bacteria in the oral cavity to reduce odor; Poria cocos can strengthen the spleen and remove dampness, blocking the upward flow of dampness and turbidity that causes halitosis; black tea neutralizes the bitterness of the raw materials and provides tea polyphenols and theaflavins to assist in antibacterial activity, while also astringing oral odor; apple has a sweet and sour taste that balances the flavor, and pectin absorbs residual odor, improving drinking compliance. Through the synergistic combination of the five raw materials, the plant-based beverage can clear liver and stomach heat and spleen and stomach dampness from the root, while inhibiting harmful bacteria in the oral cavity and intestines, thereby reducing halitosis and bitter taste, and achieving a rapid and lasting therapeutic effect on bitter taste and halitosis.

The application discloses an antioxidative slow-release fresh-keeping hydrogel containing an encapsulated theaflavins supermolecule, which comprises the following raw materials in parts by weight: 3-6 parts of the encapsulated theaflavins supermolecule, 1-6 parts of epigallocatechin gallate, 2-4 parts of sodium alginate, 2-3 parts of gellan gum, 1-3 parts of carboxymethyl chitosan, 1-4 parts of hydroxypropyl beta cyclodextrin, 0.05-0.1 parts of gluconic acid-delta-lactone, 0.05-0.1 parts of calcium chloride, 1-3 parts of tea flower essential oil, 1-2 parts of locust bean gum and 0.1-0.2 parts of lysozyme. The antioxidative slow-release fresh-keeping hydrogel containing the encapsulated theaflavins supermolecule has a significant antioxidative fresh-keeping effect (p<0.05) when applied to meat products (especially bacon or meat sausages), and also has the effects of keeping moisture (p<0.05) and inhibiting typical meat spoilage bacteria (p<0.05). The application further discloses the encapsulated theaflavins supermolecule, which is prepared by using a nano-encapsulation technology and taking theaflavins as a raw material and modified wheat protein and deacetylated chitosan as wall materials.

The invention discloses a process for extracting theaflavin and theabrownin from a tea raw material. The process comprises the following steps: carrying out enzymatic oxidation and solid-liquid separation on a tea raw material, and carrying out extraction, membrane separation and resin chromatography on the liquid to prepare theaflavin with the purity of more than or equal to 20%; microbial strains are inoculated into solid residues for solid-state fermentation, fermentation products are subjected to extraction, MVR mechanical vapor recompression low-temperature concentration, ethanol low-temperature alcohol precipitation and nanofiltration desalination, and theabrownin with the purity larger than or equal to 90% is obtained. The whole process is completed in the same continuous system, a solid outlet of the solid-liquid separation device is directly connected with the fermentation equipment, full-component high-value utilization of tea resources is achieved, and the system has the outstanding advantages of being excellent in product purity, high in production efficiency, capable of saving energy, environmentally friendly, low in cost and the like. The method is suitable for large-scale production of high-quality tea pigment in the fields of functional food, health care products and the like.

The application belongs to the technical field of fish feed additives, and discloses a fish feed for improving the quality of fish meat after freezing and thawing and application thereof. The fish feed comprises a basic feed and theaflavins, and the mass percentage of the theaflavins in the fish feed is 0.02-0.06%. The application is to improve the anti-freezing tolerance of grass carp muscle from the source through feeding intervention, effectively inhibit the growth of ice crystals and lipid oxidation in the subsequent freezing and thawing process, significantly improve the texture properties (such as chewiness and cohesiveness) of muscle, and maintain the integrity of cell structure. The application method can be quickly popularized, has the advantages of simple operation, low cost, significant improvement effect and the like, and provides an effective way for solving the quality deterioration problem of aquatic products in the freezing, storage and transportation process.

The invention relates to the technical field of beer brewing, in particular to dark tea flavored alcohol-free beer suitable for gout people and a preparation method of the dark tea flavored alcohol-free beer. The beverage is prepared from the following components in percentage by weight: 10 to 15 parts of an aged golden flower dark tea extract, 35 to 45 parts of a barley malt extract, 20 to 25 parts of an oat malt extract, 10 to 15 parts of a rice extract, 0.2 to 0.3 part of beer yeast, 2 to 5 parts of modified montmorillonite, 0.05 to 0.1 part of a compound enzyme preparation, 0.5 to 1 part of maltitol, 0.1 to 0.15 part of humulus lupulus and 80 to 100 parts of brewing water. The black tea beer has the advantages that malt aroma and fine foam of traditional beer are reserved, layering sense is increased due to the mellow flavor of the black tea, and tea polyphenol, theaflavin and other ingredients in the black tea have antioxidant and anti-inflammatory characteristics, so that generation of uric acid can be inhibited, excretion can be promoted, and joint inflammation can be relieved. In addition, caffeine in the dark tea can stimulate kidney diuresis and assist discharge of uric acid.

The application discloses a method for preparing high TF content black tea by combining cyclic light wilting with exogenous complex enzyme oxidation, and the method is characterized in that the high TF content black tea is prepared from fresh leaves with a bud and two leaves, which are used as raw materials, and have an EC content higher than 2.0%, an EGC content higher than 3.0% and a total catechin content higher than 15.0%, and are processed through seven procedures of cyclic light wilting by a wilting machine, complex enzyme treatment, green tea shaking, rolling, de-blocking, fermentation and drying. The method can reduce the bitterness and astringency of black tea by regulating the substrate for the formation of theaflavins of the raw materials, and can control the formation and accumulation of theaflavins in the processing of black tea by adding complex enzymes and matching low-temperature fermentation technology, so that a high TF content black tea with a theaflavin content higher than 0.35% is finally prepared. The process can be widely applied to the field of black tea processing and improves the utilization rate of summer and autumn tea.

The invention belongs to the technical field of fish feed additives, and discloses a fish feed for improving the quality of frozen and thawed fish meat and application of the fish feed. The fish feed comprises a basal feed and theabrownin, wherein the mass percentage of the theabrownin in the fish feed is 0.02-0.06%. According to the application, through feeding intervention, the anti-freezing tolerance of grass carp muscles is improved from the source, ice crystal growth and lipid oxidation can be effectively inhibited in the subsequent freezing and thawing process, the texture characteristics (such as chewiness and cohesiveness) of the muscles are remarkably improved, and the cell structure integrity is kept. The application method can be quickly popularized, has the advantages of simplicity in operation, low cost, remarkable improvement effect and the like, and provides an effective way for solving the problem of quality degradation of aquatic products in the freezing storage and transportation process.