63results about How to "Passivation activity" patented technology

The invention provides a broad spectrum heavy metal activity deactivator preparation method. The present invention relates to a soil conditioning agent preparation method, which comprises the following steps: (A) taking humic acid-rich peat, digest compost or a forest soil humus layer, and carrying out screening to provide a spare use; (B) adding the humic acid-rich material to HCl or HNO3 to soak, and stirring 2-3 times; (C) filtering the soaked material with a bamboo drying pad, washing 2-3 times with clear water, and carrying out air drying to a moisture content of less than 5%; (D) sequentially adding ZnSO4.7H2O, sodium silicate and sodium selenite to the material obtained from the step (C), carrying out aging on the mixed material for 2-3 days and uniformly mixing; and (E) adding limestone powder to the material obtained from the step (D), and completely and uniformly mixing to prepare the broad spectrum heavy metal deactivator. With the combination inhibitor prepared by the preparation method, activities of soil heavy metals can be significantly inactivated, the heavy metals can be inhibited from entering the food chain, and risks on human health by the heavy metals can be reduced.

The invention discloses a preparation method for a tea extract, belonging to the technical field of extraction of effective components of tea leaves. The preparation method comprises the following steps: firstly, carrying out low-temperature rapid freezing treatment on high-quality commercial tea leaves; then immediately crushing; then combining a high-voltage pulsed electric field (PEF for short) technology, an ultrasonic treatment technology and a low-temperature enzymolysis technology; and carrying out low-temperature extraction in a whole process. According to the preparation method for the tea extract, the loss of effective components, caused by high-temperature processing, is avoided, and the extraction rate of the effective components of the tea leaves is also improved. The process is simple and low in cost; the introduction amount of extraneous food additives, processing auxiliary agents and chemical substances is reduced; the natural nutritional ingredient and the flavor of the tea leaves are kept to the greatest extent, the low-carbon production is realized and the environment is protected.

The invention discloses a method for stabilizing the wheat bran specially used for the whole wheat flour, which is mainly characterized in that: the wheat bran is treated by steam and dried by the ultraviolet microwave so that the wheat bran is stabilized. Due to the adoption of the method, the activity of the lipase and the lipoxygenase in the wheat bran can be reduced significantly, and the storage stability of the wheat bran can be improved significantly. In addition, the treated wheat bran has little difference from the non-stabilized wheat bran in colour and organoleptic quality, the content of total phenols in the treated wheat bran is increased slightly, and the antioxidant activity of the treated wheat bran is improved obviously. The method is simple and practical, has an obvious effect and effectively solves a series of problems of the existing method for stabilizing the wheat bran that the equipment has high cost, the operation process is burdensome and complicated, the wheat bran has poor storage stability, the colour of the stabilized wheat bran is dark, the efficacy and the activity are lost, and the stabilized wheat bran is not suitable for producing the whole wheat flour, thereby creating the conditions for producing the high-quality whole wheat flour with long shelf life.

The invention provides a mineral-based soil remediation agent, and a preparation method and application thereof. The mineral-based soil remediation agent is prepared by mixing calcium raw materials, sodium raw materials and silicate minerals, and then performing calcination and crushing; or further performing water immersion treatment on the mineral-based soil remediation agent, then performing solid-liquid separation, and then drying the obtained solid. The effective silicon content (solubility in citric acid) in terms of SiO2 is more than or equal to 20 wt%, and the effective calcium contentin terms of CaO is more than or equal to 40 wt%, and the content of harmful elements such as Hg, As, Cd, Pb and Cr is lower than 50 ppm.

The invention relates to a bean dregs dietary fiber superfine powder and a preparation method thereof. The present invention uses wet ultrafine grinding and extrusion technology to process fresh bean dregs in time and process soybean dietary fiber powder in one step, that is, to obtain bean dregs meal by heating bean dregs to eliminate enzymes, remove fishy smell, grind, homogenize, extrude, and dry. Fiber micropowder. The present invention integrates the preparation of bean dregs dietary fiber and the modification of dietary fiber into one process, which simplifies the process; the process adopts all physical treatment methods, which avoids the safety caused by residues of additives or the impact on product composition. Negative effects and other issues, and no by-products, can realize the simultaneous completion of resource utilization and environmental protection. Compared with ordinary soybean dregs dietary fiber powder, the product of the present invention has enhanced function, improved taste and color, and passivated factors causing bad flavor, and is widely used in the fields of food and health food.

The invention discloses a planting method of jute in heavy-metal contaminated soil. The method comprises the following steps of: A, preparing soil and building a field, and applying passivator to reduce activity of heavy metal in the soil; B, selecting a specific jute variety with strong heavy metal contamination resistance, sowing in an enough amount at proper time to guarantee full seedlings; C, determining appropriate close planting, thinning / finally singlings in good time, and reserving enough basic seedlings; and D, intertilling / weeding in time, rationally topdressing / irrigating to culture effective strong plants; E, reinforcing prevention and control of diseases and insect pests to realize high yield of jute. By the jute planting method, the average yields of raw stems in light, medium and heavy contaminated jute fields are respectively 181.0+ / -16.4, 174.9+ / -15.7 and 158.5+ / -15.3kg / mu, which reaches the high-yield level of the jute growing area in South China; and the content of heavy metal in raw jute can be controlled in a range of related standard limit, so that agricultural safety and effective utilization of heavy metal contaminated soil can be realized. The method is simple in technology and practical, and has wide application prospect in broad heavy metal contaminated areas.

The invention discloses a soil conditioner and a preparation method of the soil conditioner, and belongs to the soil field. The soil conditioner is obtained by roasting at least one type of marine organism shells used as raw materials at 800-1200 DEG C. The marine organism shells are optimally oyster shells. The soil conditioner prepared through the preparation method has super strong adsorption and regulation capabilities, improves the physical and chemical properties of soil, and enables the soil to form a good granular structure; the effectiveness of macroelements and microelements is improved, therefore, the fertilizer rate is reduced, and crop output can be increased remarkably; the activity of toxic substance in the soil can be passivated remarkably, so that the phenomenon that aluminum ions cause a crop root system to be poisoned, rotted and dead is greatly reduced, and the capability of crops for stress resistance and resistance to diseases and pests is enhanced; physiological diseases of various crops can be effectively prevented and treated, beneficial cenobium in the soil can multiply at a high speed, and therefore the ecological restoration function of the soil is achieved.

The invention discloses a processing method of green tea, belonging to the technical field of tea processing. The method comprises the steps of withering, rocking, fixation, rolling and baking and concretely comprises the steps of naturally withering picked tea leaves in the open air; then, withering by blowing the tea leaves by an air blower in a room for 2-3 hours; putting the withered tea leaves into a rocking machine, and carrying out rocking for three times; and after that, performing fixation on the tea leaves, rolling, baking, and packaging to obtain the green tea. The green tea has the characteristics of having green leaves with red edges, and being golden in liquor color, fragrant, mellow in taste as well as sweet and fresh in aftertaste after being drunk.

The present invention provides a preparation method of needle tea. Said preparation method includes the following steps: steaming, dehydration, primary rolling, hot air drying, further rolling, forming and drying so as to obtain the invented finished product.

The invention belongs to the food processing field of staple food and relates to buckwheat steamed bread with a high flavone content and a preparation method of the buckwheat steamed bread. The buckwheat steamed bread is prepared from the following components: high gluten wheat flour, tartary buckwheat powder, sweet buckwheat powder, alpha-amylase, pentosanase, water and yeast. The preparation method of the buckwheat steamed bread comprises the following steps of: firstly, carrying out vacuum freeze drying and ultrafine grinding treatment on the tartary buckwheat powder and the sweet buckwheat powder, respectively; then, uniformly mixing the high gluten wheat flour, the tartary buckwheat powder, the sweet buckwheat powder, the alpha-amylase, the pentosanase and the yeast and then adding water to the mixture; and finally, mixing, tabletting, dividing and forming, fermenting, cooking, cooling and packaging to obtain the buckwheat steamed bread with the high flavone content. According to the buckwheat steamed bread with the high flavone content and the preparation method of the buckwheat steamed bread, the content of the favone in the buckwheat is improved, processing performances, such as elasticity and viscosity, of buckwheat dough are improved, and the rough mouthfeel of the product is improved by applying advanced technologies such as vacuum freeze drying, ultrafine grinding and bio-enzyme treating. The buckwheat streamed bead produced by the preparation method disclosed by the invention is fine in mouthfeel, can be used as staple food for long-term consumption, higher in flavone content, and is provided with a healthcare function of regulating lipid and reducing blood glucose by buckwheat.

The invention discloses a method for planting kenaf on heavy metal contaminated soil. The method includes the following steps: A, preparing the land and building an area, and applying an passivant to reduce the activity of soil heavy metal; B, selecting a specific kenaf variety with high heavy metal pollution resistant capacity, sowing sufficiently in due time, and guaranteeing a full stand through one sawing; C, determining suitable close planting, performing thinning and final singling in due time, and reserving basic seedlings; D, intertilling and weeding timely, topdressing and irrigating reasonably, and cultivating effective strong plants; and E, strengthening pest control and achieving high yield of the kenaf. The original kenaf outputs of mild, moderate and serious contaminated kenaf gardens are 276.2+ / -25.5, 247.6+ / -23.4 and 220.9+ / -21.2kg / mu respectively when the method is used for planting the kenaf, the high yield level in southern kenaf areas in our country is reached, content of heavy metal in the original kenaf can be controlled within a relative standard limit, agricultural safety and efficient utilization of the heavy metal contaminated soil are achieved, the technique is simple and convenient, the method is easy to implement, and an extremely wide application prospect is provided in vast heavy metal contaminated areas.

The invention discloses a calcium-iron-silicon-based composite material for restoring heavy metal polluted acid soil and application thereof. The mass ratio of component elements of the composite material is calcium:iron:silicon:manganese:magnesium:phosphorus:aluminum= 30-40:19-25:8-12:1-3:5-6:1-3:2-5, the composite material is particularly prepared from, by volume, 55-70% of calcium silicate, 20-30% of calcium ferrite and 5-15% of compound mixture, and the compound mixture is a mixture of calcium-iron-aluminum oxides, calcium iron silicate, calcium aluminate, calcium-aluminum oxides, calcium-manganese-iron oxides, hydroxyl aluminium phosphate and hydroxyl manganese phosphate. The composite material is used for improving and restoring the heavy metal polluted acid soil, the pH value of the soil can be increased by 0.5-2.5 units, the content of effective state heavy metal in the soil is reduced by 64-98%, the content of heavy metal in agricultural products is reduced by 33-94% compared with a control group, and the yield of the agricultural products is increased by 16-1412% compared with the control group.

The invention discloses an alkaline organic fertilizer for restoring soil polluted by heavy metals and a preparation method of the alkaline organic fertilizer, and relates to the technical field of agricultural fertilizers. The alkaline organic fertilizer is prepared from, by weight, 1-3 parts of urea, 1-3 parts of potassium sulphate, 2-6 parts of diammonium phosphate, 10-30 parts of tobacco straw, 30-40 parts of alkaline ash, 15-35 parts of livestock manure, 10-30 parts of bean stalks, 10-30 parts of purple soil, 1-3 parts of microelements, 0.5-1.5 parts of biological bacteria, 3-5 parts of lime nitrogen and 0.02-0.04 part of nitragin. The alkaline organic fertilizer has a good restoring effect on the soil polluted by the heavy metals, is suitable for being used in acidic soil, can be used for farmland soil heavy metal pollution restoration and ecological improvement in southern paddy fields in China, and can also be used for dry farmland soil heavy metal pollution restoration and ecological improvement in the south.

The invention belongs to the technical field of storage and fresh-keeping of agricultural products, in particular relates to a fresh-keeping method of fresh fruits, and specifically relates to a fresh-keeping method of combining a compound solution containing melatonin, gibberellin and salicylic acid with liquid nitrogen fumigation. The steps are as follows: spraying fruits with the compound solution containing melatonin, gibberellin and salicylic acid one day before harvest, transferring the fruits to a closed space for short-time fumigation with liquid nitrogen after harvest, and then immediately transferring the fruits to a spontaneous controlled atmosphere packaging for low temperature storage. The compound solution containing melatonin, gibberellin and salicylic acid is combined withliquid nitrogen fumigation, thus the fresh-keeping method can not only realize sterilization and inhibit the synthesis of ethylene, but also inactivate fruit enzymes, and at the same time, and can achieve fast precooling so as to maintain the storage quality of fruits, achieves the purpose of prolonging the storage period and improving the fresh-keeping effect of fruits; and at the same time, theoperation is convenient, the efficiency is improved, the practicability is high and the application is convenient.

The invention provides a soil conditioner for adjusting soil acidity or alkalinity and alleviating soil salinization and a preparation method thereof. The soil conditioner comprises the following ingredients (by weight): 25-65 parts of fermented spent mushroom compost, 15-45 parts of grass and wood charcoal, 5-25 parts of oyster shell powder, 3-15 parts of potassium fulvic acid, 2-10 parts of algaextract, and 1.5-11 parts of Bacillus spp. By synergism of spent mushroom compost, oyster shell powder, potassium fulvic acid and alga extract and through microbial regulation effect of the added microbial inoculant, soil structure can be remarkably improved, gas permeability of soil is enhanced, soil micro-environment is restored, quantity and types of useful bacterial colonies in soil are increased, soil acidity or alkalinity is regulated, soil salinization is alleviated, and activity of heavy metals is inactivated. Cyclic utilization of wastes such as spent mushroom compost, grass and woodcharcoal and the like is realized, and production cost is low. The invention is beneficial to large-scale industrial production and large-scale promotion and application.

The invention relates to an aralia mandshurica green-protecting compounded agent and belongs to the field of agricultural product processing. The invention develops a food-grade compounded green-protecting agent specially used for aralia mandshurica and aims at solving the problem that the aralia mandshurica can get yellow easily and is not applicable to long-term storage and the current situation that a green-protecting agent containing heavy metal ions is mainly adopted for green protecting in the fruit and vegetable fresh-keeping industry. The aralia mandshurica blanched by virtue of the aralia mandshurica green-protecting compounded agent is emerald green in overall, full in appearance and long in preservation time. The green-protecting compounded agent provided by the invention has the advantages that on the basis that three green-protecting agents, namely vitamin C, cysteine and sodium sulfite, respectively fully play roles, citric acid and calcium chloride are added to enhance the synergistic green-protecting effect, so that chlorophyll of the aralia mandshurica is effectively protected, and the chlorophyll loss ratio is reduced; and no heavy metal ion is added, so that the green-protecting compounded agent serves as a green, safe and efficient green-protecting method, and a basis can be provided for development of the industries such as aralia mandshurica green-protecting and fresh-keeping, green processing of aralia mandshurica and development of related green foods.

The invention provides a making method of canned olea europaea fruits. The making method comprises the following steps of selecting fruits, performing cleaning, performing soaking in an aqueous alkaline solution, performing pickling, sealing cans and performing sterilization. The making method is characterized by comprising the specific steps of putting acid-pickled and hardened olea europaea fruits into boiling water, performing stirring for 2-5 minutes, fishing out the stirred olea europaea fruits, and performing cooling with cold water; pricking or carving the acid-pickled, hardened and cooled olea europaea fruits; adding an appropriate quantity of food additives to the pricked or carved olea europaea fruits at twice, putting the olea europaea fruits with the food additives into water, boiling over the olea europaea fruits, and pouring the boiled olea europaea fruits into a vat for standing for 20-26 hours; fishing out the olea europaea fruits in which materials are permeated, adding an appropriate quantity of food additives, putting the processed olea europaea fruits into the water, boiling over the olea europaea fruits, fishing out the boiled olea europaea fruits, and performing rinsing to remove the food additives on the surface of the peel of the olea europaea fruits; and sealing the cans, loading the olea europaea fruits after surface treatment, adding a food additive aqueous solution, performing sealing, and performing covering. The canned olea europaea fruits made by the making method disclosed by the invention are free from bitter taste, the olea europaea fruits are consistent in surface color and uniform in hardness, permeated materials in the olea europaea fruits are uniform, and canned olea europaea fruits are consistent in taste.

The invention discloses a diffusion technology for a crystalline silicon solar cell. The diffusion technology includes the step of furnace tube diffusion. Before furnace tube diffusion is carried out, a silicon wafer is oxidized through illumination rapid heat treatment, and an even oxidation film is generated on the surface of the silicon wafer. By means of the diffusion technology for the crystalline silicon solar cell, as the even oxidation layer is formed after the silicon wafer is etched and before phosphorus atoms or boron atoms are deposited, the uniformity of diffused p-n junctions is improved, the in-wafer uniformity and the inter-wafer uniformity of the sheet resistance of the silicon wafer are improved accordingly, and the efficiency of the cell is effectively improved; in addition, when the diffusion sheet resistance is increased to higher than 90 omega per sheet, the uniformity of the sheet resistance can also be effectively controlled; meanwhile, the etched surface is effectively protected through the even oxidation layer, and the silicon wafer is prevented from being polluted by particles in the air or man-made contact; in addition, residual organic matter generated by additives during etching can be pre-removed in the oxidation process.

The invention discloses a preparation method of brown rice flour for brown rice noodles and a preparation method of the brown rice noodles. The preparation method of the brown rice flour for the brown rice noodles comprises the following steps: grinding brown rice into white rice and rice bran by using a rice mill; extruding and puffing the rice bran, and conducting crushing and sieving to prepare rice bran powder; soaking the white rice in water, and successively conducting draining, crushing and sieving to prepare white rice flour; and adding the rice bran powder into the white rice flour, conducting even mixing and then performing drying so as to obtain the brown rice flour for the brown rice noodles, wherein the mass of the rice bran powder accounts for 8-10% of the mass of the white rice flour. According to the preparation method, the rice bran is extruded and puffed, so the activity of various enzymes such as lipase and lipoxygenase in the rice bran is well passivated, and the storage period of the brown rice flour is prolonged.

The present invention discloses high-quality and low-temperature instant black tea powder and a preparation technology thereof. The high-quality and low-temperature instant black tea powder is prepared by the following steps: material selecting, withering, rolling, stacking and placing, first fermentation treating, hot water soaking, filtering, mixed microwave treating of a first filtering residue and a part of a first filtrate, second fermenting, ultrasonic treating after mixing of the remaining part of the first filtrate and fermentation liquid, drying, etc. A ratio of theaflavins, thearubigins and theabrownins is appropriate. The preparation technology improves drinking flavor of the brewed black tea powder and is also good in low-temperature instant dissolution effects.

The invention discloses a method for passivating the activity of dissolved polyphenol oxidase and membrane-bound polyphenol oxidase. The method comprises the following steps: step 1, taking fruit andvegetable materials, and carrying out first ultrahigh pressure treatment; step 2, performing ultrahigh-pressure homogenization treatment on the fruit and vegetable materials for 1-3 times at room temperature under a pressure value of 100-400MPa and an inlet temperature of 35-55 DEG C; and step 3, after a citric acid solution or a tartaric acid solution is added, performing secondary ultrahigh-pressure treatment at a room temperature under a pressure value of 150-600 MPa for a pressure maintaining time of 10-30 min. According to the invention, the activity of PPO in the juice can be effectivelypassivated, the sPPO activity inhibition rate is 98%, and the mPPO activity inhibition rate is 95%. Compared with traditional heat treatment, the method not only has a good passivation effect and maintains the flavor of the fruit juice, but also facilitates the improvement of the sensory quality of the fruit juice by an ultrahigh-pressure homogenization technology.

The invention relates to the technical field of ruminant feed. The invention discloses a daily ration for preventing ruminant foam type rumen flatulence. The daily ration comprises the following components in parts by weight: 25-30 parts of corn, 5-10 parts of wheat bran, 15-25 parts of a cake feed, 10-25 parts of oat grass, 20-35 parts of ramie, 1.3-2.0 parts of an inorganic additive, 0.5-2 partsof a premix and 5-10 parts of plant peel residues. The preparation method comprises the following steps: carrying out superfine grinding and high-pressure cooking on the corn, the wheat bran, the cake meal feed and the plant skin residues to obtain a first component; and mixing the first component with oat grass, ramie, an inorganic additive and the premix to obtain a second component. The dailyration disclosed by the invention is rich in dietary fibers, proteins, saccharides and trace elements required by ruminant production, and can inhibit the loss of nutrients of the daily ration by microorganisms in rumen, thereby inhibiting the generation of methane in rumen.

The invention discloses a pure Tieguanyin tea beverage and a preparation method thereof, belonging to the field of tea beverage processing. The preparation method comprises the following steps: at first, carrying out low-temperature rapid freezing treatment on high-quality Tieguanyin tea used as a raw material; then immediately crushing; combining a high-voltage pulsed electric field technology, an ultrasonic treatment technology and a low-temperature enzymolysis technology; carrying out an ultrafiltration technology and the like to extract tea soup at a low temperature in a whole process; and finally, blending, finely filtering, sterilizing and filling to obtain the pure tea beverage which has natural quality and flavor, pure and rich tea flavor and obvious health-care effects. The tea beverage is scientific and reasonable in formula and simple in processing process; extraneous food raw materials, essences, pigments and chemical substances are not added; only a sour agent and a sweetening agent which are the most regular in a beverage industry are used; in the whole process, a low-temperature processing technology is adopted, so that the quality and the flavor of natural Tieguanyin tea are kept to the greatest extent; the Tieguanyin pure tea beverage is the true Tieguanyin pure tea beverage.

The invention provides a processing method of flower and fruit fragrance type Liubao sunned raw tea, and belongs to the technical field of tea processing. The method comprises the following steps: (1) picking fresh leaves; (2) sunning for the first time; (3) withering; (4) sunning for the second time; (5) performing fine manipulation of green tea leaves; (6) airing; (7) performing fixation for the first time; (8) rolling for the first time; (9) performing fixation for the second time; (10) rolling for the second time; (11) drying in the sun; and (12) storing. The method solves the problems that the finished product of Liupao sun-withered raw tea processed by the traditional technological process does not highlight the original taste, has a similar green tea flavor, is difficult to transform in the later stage, has poor flavor quality, strong smoky flavor, bitter flavor, heavy taste, foreign flavor and the like, so that the Liupao sun-withered raw tea processed by the method has good sun-withered raw tea quality characteristics; and the tea has mellow and refreshing taste, light brown and bright soup color and rich flower and fruit fragrance.

The invention provides a litchi and apple mixed juice beverage and a preparation method thereof. The litchi and apple mixed juice beverage contains at least 20% of original juice, wherein the mass proportion of litchi juice to apple juice is 3:1, the mass percentage of soluble solids is 11-12%, and the total acidity (by citric acid) is 0.15-0.25%. The preparation method mainly comprises the steps of preparing the litchi juice and blending the two fruit juices. The invention improves the litchi juice extracting method, and optimizes the formula of the mixed juice beverage. The prepared product integrates the nutritional and flavor characteristics of litchi and apples, overcomes the defects of single fragrance and flavor in the single fruit juice, uses the fresh taste of apple juice to cover the sweet taste of litchi juice, simultaneously has the fragrance and flavor of litchi and apples, and tastes fresh and harmonious. The invention adds the varieties of beverages of litchi juice and apple juice, can satisfy the consumer's requirements for beverage diversification, has positive actions for promoting the juice beverage processing technology and litchi deep processing, and has favorable social benefit.

The invention discloses a green tea processing process in the technical field of tea processing. The green tea processing process comprises steps as follows: S1, sorting: fresh and brittle celery is selected, rhizomes are removed, and only celery leaves are retained, washed clean with clean water and cut into segments which are 3-5 cm long; S2: blanching: pH of hot water is adjusted to range from 7 to 8 with a 0.02%-0.05% Na2CO3 solution and heated to 85-95 DEG C to blanch the selected celery for 3-5 min; S3: crushing: the blanched celery in S2 is crushed and filtered with a filter net, and celery juice is obtained and left to stand; S4, centrifugal treatment: the celery juice is subjected to centrifugal treatment with a high-speed centrifuge, salt and citric acid are added in the centrifugal process, and the weight ratio of the celery juice, the salt and citric acid is 30:1:1; S5: processing: the celery juice is packaged in a ball made of propolis, aged tea and propolis balls are added to a tea bag, and novel green tea is formed. With the adoption of the scheme, the tea water obtained after the aged tea is brewed is light green.

The invention relates to a preparation method for high-yield bean cured without beany flavour. The method comprises a bean curd drying and crushing step, a softening step, a flaking step, a step of grinding blank pieces into slurry, cooking the slurry, pouring brine, and pressing and forming, wherein the softening step refers to adopting indirect steam to perform step type softening on the crushedsoy beans. The preparation method greatly reduces the amount of bean dregs, so that the total amount of proteins adsorbed by the bean dregs is also reduced, the product yield is increased, activity of lipoxygenase is passivated, and therefore, the bean curd is free of beany flavour, and bitter taste is eliminated. The conventional method generates a great deal of bean dregs through a process of soaking, grinding into slurry, cooking the slurry, pouring brine, forming and pressing, so that a great amount of proteins lose, and the product yield is low; and meanwhile, the process directly adoptssoy beans as a raw material, and passivating treatment is not performed on lipoxidase, so that the beany flavour of bean curd is severe, and bitter taste is generated.

The invention discloses a manufacturing method of tangerine scented ancient tree black tea. The manufacturing method is characterized by including the step of subjecting Fengqing big-leaf tea serving as a raw material to selecting, withering, rolling, freezing, fermenting and drying. By the step of freezing before fermenting, loss of beneficial components can be reduced. By raw material selection and processing process control, flavors of tea polyphenol, amino acids and some carbohydrates in tea can be combined. Obtained ancient tree black tea leaves are fleshier than Yunnan black tea leaves, and plump and compact strips, glossiness in color, thick tea flavor, honey sweetness in taste, transparency and brightness in liquor color, high throat comfort, evident effects of sweetness lingering and saliva secretion promoting and toughness of infused tea stems are realized.

The invention discloses freeze-dried siraitia grosvenorii slices and a preparation method thereof and belongs to the technical field of food processing. The freeze-dried fructus siraitiae slices are prepared through processes of selecting, slicing, carrying out fixation, naturally drying by air, pre-freezing, carrying out secondary freezing, deeply freezing and the like. Compared with the prior art, the method has a simple and easily-controlled process, short freezing and drying time, low energy consumption and high production efficiency; a hot water fixation technology is adopted so that the activity of enzymes including polyphenol oxidase and the like in siraitia grosvenorii peels is deactivated; three times of freezing processes are adopted so that moisture in siraitia grosvenorii is volatilized in sequence and the separation of peels and pulp, caused by moisture drying, is avoided; meanwhile, the color and luster, aroma, taste, nutrient components and the like of the siraitia grosvenorii are kept very well.