CN111838364A

CN111838364A - Process for producing black tea powder by dry tea mixed fermentation and steam extraction device

Info

Publication number: CN111838364A
Application number: CN202010892391.8A
Authority: CN
Inventors: 马喆
Original assignee: Hubei Yulong Bioengineering Co ltd
Current assignee: Hubei Yulong Bioengineering Co ltd
Priority date: 2020-08-31
Filing date: 2020-08-31
Publication date: 2020-10-30

Abstract

The invention provides a process for producing black tea powder by dry tea mixed fermentation, which comprises the following steps: s1, mixing the dry tea and the fresh tea, fermenting, leaching the fermented mixture with hot water at 65-85 ℃, collecting leaching liquor, and concentrating the leaching liquor to 30-40% of the initial weight to obtain primary leaching liquor; s2 hot water leaching, pressing and drying the tea residue until the water content is 15-20%, wherein: concentrating the liquid obtained by pressing to 50-60% of the initial weight to obtain re-extracting solution, drying the obtained product, extracting by using steam, and condensing the extracted steam into condensate to obtain three extracting solutions; s3, mixing the primary extract and the secondary extract, filtering, mixing the three extracts with undersize products obtained by filtering, adjusting the water content to 80-90%, and spray-drying to obtain the black tea powder. The invention adopts a plurality of steps to extract the raw materials and the tea leaves, effectively reduces the residual effective components in the tea leaves to the minimum, and simultaneously provides a device capable of carrying out steam extraction on the tea leaves, thereby realizing the high-efficiency extraction of the tea leaves.

Description

Process for producing black tea powder by dry tea mixed fermentation and steam extraction device

Technical Field

The invention relates to the technical field of black tea powder production processes, in particular to a process for producing black tea powder by dry tea mixed fermentation and a steam extraction device.

Background

The black tea powder is prepared by taking tea with high fermentation degree as a raw material, extracting with hot water, concentrating, and then carrying out spray drying, and is rich in various nutrient substances contained in black tea, wherein the black tea comprises the following components in percentage by weight:

the content of phenolic compounds is about 20-30%, and catechin compounds are the most important components, accounting for 70%. The catechin has powerful and rich health care functions, is the main force of the curative effect of black tea, and has the effects of preventing angiosclerosis, resisting the damage of radioactive substances, diminishing inflammation, sterilizing, astringing to stop bleeding, detoxifying, delaying aging, resisting cancer, reducing blood fat, reducing blood sugar, reducing blood pressure and the like through experiments;

purine bases: comprises caffeine, theophylline, theobromine and the like, and accounts for about 4 percent of the black tea. The three alkaloids have similar functions, but caffeine is most effective in exciting central nerve to refresh mind, and theophylline has stronger effects of tonifying heart, promoting urination, dilating blood vessel, relaxing smooth muscle, etc. than caffeine;

aromatic substances: although the aromatic substances in the black tea only account for 100-300ppm, the aromatic substances in the black tea can account for 325 types. They not only can remove the fishy smell of the oral cavity, but also have the functions of bacteriostasis, inflammation diminishing, tranquilizing, pain easing and the like;

amino acids: glutamic acid and the like are helpful for reducing blood ammonia and treating hepatic coma; methionine, etc. can regulate fat metabolism;

other elements: fluorine contained in the black tea is a great tool for preventing decayed teeth and osteoporosis; the bait helps to reduce blood pressure; the acephate polysaccharide is regarded as important in the research of radiation protection.

The black tea powder can be directly brewed and drunk as a terminal product, and can also be used as a processing raw material of other products, such as: beverages, baked products, and the like, and has wide application fields and high nutritional and health-care values.

The black tea powder processing technology in the prior art has the defects in the aspect of the completeness of the extraction of effective components, and a large amount of phenols, amino acids and other components are still remained in tea residues after extraction, so that the waste of raw materials is caused.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a process for producing black tea powder by dry tea mixed fermentation, which solves the problem of raw material waste caused by more effective components remained in tea leaves after extraction in the prior art.

According to the embodiment of the invention, the process for producing the black tea powder by dry tea mixed fermentation comprises the following steps:

s1, mixing the dry tea and the fresh tea, fermenting, leaching the fermented mixture with hot water at 65-85 ℃, collecting leaching liquor, and concentrating the leaching liquor to 30-40% of the initial weight to obtain primary leaching liquor;

s2 hot water leaching, pressing and drying the tea residue until the water content is 15-20%, wherein:

concentrating the liquid obtained by pressing to 50-60% of the initial weight to obtain re-extracting solution,

drying the obtained product, extracting with steam, and condensing the extracted steam into condensate to obtain three extractive solutions;

s3, mixing the primary extract and the secondary extract, filtering, mixing the three extracts with undersize products obtained by filtering, adjusting the water content to 80-90%, and spray-drying to obtain the black tea powder.

Further, the fermentation conditions in S1 were: the temperature is 50-60 ℃, and the time is 6-8 h;

the proportion of the dry tea to the fresh tea is 9: 1-3: 1, adding water which accounts for 10-15% of the weight of the dry tea and is at the temperature of 35-40 ℃ into the dry tea, and standing for 1-2 hours.

Further, the concentration includes one or more of fine filtration, ultrafiltration, membrane concentration, and vacuum concentration.

Further, the steam used for the steam extraction in S2 is derived from the excess liquid obtained by the concentration.

Further, the water content of the black tea powder is 3-4%.

According to the embodiment of the invention, the steam extraction device for realizing the steam extraction comprises an extraction box and a carrying frame which is arranged in the extraction box in a drawing and inserting mode, wherein the carrying frame is inserted into the extraction box and then divides the extraction box into an upper part and a lower part, and a steel mesh is fixedly connected to the bottom of the carrying frame;

the steam extraction device also comprises an air inlet pipe and a condensation component which are respectively and fixedly connected with the upper end and the lower end of the extraction box.

Furthermore, the condensation component comprises a condensation cylinder, the upper end of the condensation cylinder is fixedly connected with the extraction box, and the lower end of the condensation cylinder is fixedly connected with a collection box;

the condensation component also comprises a spiral condensation pipe arranged in the condensation cylinder, the upper end of the condensation pipe is communicated with the extraction box, and the lower end of the condensation pipe is communicated with the collection box;

and the condensation cylinder is also fixedly connected with a water outlet pipe and a water inlet pipe which are positioned at the upper end and the lower end of the condensation cylinder.

Furthermore, two mounting plates which are positioned at the upper end and the lower end of the condensation cylinder are also arranged in the condensation cylinder, and the two ends of the condensation cylinder are respectively arranged on the two mounting plates;

the inlet tube with the outlet pipe is located two between the mounting panel.

Compared with the prior art, the invention has the following beneficial effects:

fresh tea is mixed into the dry tea raw material, so that the fermentation degree of the raw material can be improved, and the effective components can be dissolved more completely during hot water extraction, so that the residue in the tea residue can be effectively reduced;

further pressing the tea leaves to press out liquid parts in the tea leaves so as to reduce residue of the tea leaves;

finally, the pressed tea leaves are subjected to steam extraction again, so that the effective components in the tea leaves are taken out to the maximum extent, and the residue of the tea leaves is reduced to the minimum;

the steam extraction device who provides adopts overhead steam to get into the mode, carries out from last extraction extremely down to the material, can furthest with the active ingredient extraction in the material, it is extravagant to reduce the raw materials.

Drawings

FIG. 1 is a schematic view of the overall structure of embodiment 6 of the present invention;

fig. 2 is a schematic top view of a carrier frame according to embodiment 6 of the present invention;

in the above drawings:

the device comprises an extraction box 1, a carrying frame 2, a steel mesh 3, an air inlet pipe 4, a condensation cylinder 5, a collection box 6, a condensation pipe 7, an outlet pipe 8, an inlet pipe 9 and a mounting plate 10.

Detailed Description

The technical solution of the present invention is further explained with reference to the drawings and the embodiments.

Example 1

Adding water accounting for 10% of the weight of the black tea with high fermentation degree by adopting a spraying mode, sealing and standing for 2 hours by adopting a film, and mixing with fresh tea leaves according to the weight ratio of 9: 1, then sealing the mixture by using a film, fermenting the mixture for 6 hours at 50 ℃, and after fermentation, adding 65 ℃ hot water according to a material-liquid ratio of 1: leaching for 3h at 40 ℃, fishing out the tea residue for pressing, drying the pressed tea residue until the water content is 5%, collecting the liquid flowing out from the pressing, concentrating the liquid until 50% of the weight of the liquid is used as re-extraction liquid, and concentrating the extraction liquid until 30% of the weight of the extraction liquid is used as primary extraction liquid;

putting the dried tea leaves into a steam extraction device, performing steam extraction for 3 hours, and collecting condensate as three extract;

mixing the primary extract and the secondary extract, filtering to remove scum in the mixed solution, adding the three extracts into the mixed solution obtained by filtering, adding dextrin accounting for 3 percent of the weight of the three extracts, stirring uniformly, and performing spray drying to obtain the black tea powder.

Example 2

Adding water accounting for 12.5 percent of the weight of the black tea with high fermentation degree into the black tea by adopting a spraying mode, sealing and standing for 2.5 hours by adopting a film, and mixing the obtained product with fresh tea according to the weight ratio of 9: 2, then sealing the mixture by using a film, fermenting the mixture for 7 hours at the temperature of 55 ℃, and after fermentation, adding hot water at the temperature of 75 ℃ into the mixture according to a material-liquid ratio of 1: 45 leaching for 2.5h, fishing out the tea residue, pressing, drying the pressed tea residue until the water content is 7%, collecting the liquid flowing out from the pressing, concentrating the liquid until 55% of the weight of the liquid is re-extracted liquid, and concentrating the extracted liquid until 35% of the weight of the extracted liquid is primary extracted liquid;

putting the dried tea leaves into a steam extraction device, performing steam extraction for 2.5 hours, and collecting condensate as a three-extract;

mixing the primary extract and the secondary extract, filtering to remove scum in the mixed solution, adding the three extracts into the mixed solution obtained by filtering, adding dextrin accounting for 3.5 percent of the weight of the three extracts, stirring uniformly, and performing spray drying to obtain the black tea powder.

Example 3

Adding water accounting for 15% of the weight of the black tea with high fermentation degree by adopting a spraying mode, sealing and standing for 3 hours by adopting a film, and mixing the obtained product with fresh tea leaves according to a ratio of 3: 1, then sealing the mixture by using a film, fermenting the mixture for 8 hours at the temperature of 60 ℃, and after fermentation, adding hot water at the temperature of 85 ℃ into the mixture according to a material-liquid ratio of 1: leaching for 2h at 50 ℃, fishing out the tea residue for pressing, drying the pressed tea residue until the water content is 9%, collecting the liquid flowing out from the pressing, concentrating the liquid until the weight of the liquid is 60% of the weight of the liquid to obtain re-extraction liquid, and concentrating the leaching liquid until the weight of the leaching liquid is 40% of the weight of the liquid to obtain primary extraction liquid;

putting the dried tea leaves into a steam extraction device, performing steam extraction for 2 hours, and collecting condensate liquid as three extract;

mixing the primary extract and the secondary extract, filtering to remove scum in the mixed solution, adding the three extracts into the mixed solution obtained by filtering, adding dextrin accounting for 4 percent of the weight of the three extracts, stirring uniformly, and performing spray drying to obtain the black tea powder.

Example 4

Adding water accounting for 10% of the weight of the black tea with high fermentation degree by adopting a spraying mode, sealing and standing by adopting a film, fermenting for 8 hours at 50 ℃, and then fermenting by using hot water with the temperature of 65 ℃ according to the material-liquid ratio of 1: leaching for 3h at 40, concentrating the leaching liquor until 30% of the weight of the leaching liquor is primary leaching liquor, then filtering scum in the primary leaching liquor, adding dextrin accounting for 3% of the weight of the primary leaching liquor into the filtered primary leaching liquor, uniformly stirring, and then carrying out spray drying to obtain the black tea powder.

Example 5

Adding water accounting for 10% of the weight of the black tea with high fermentation degree by adopting a spraying mode, sealing and standing by adopting a film, fermenting for 8 hours at 50 ℃, and then fermenting by using hot water with the temperature of 65 ℃ according to the material-liquid ratio of 1: leaching for 3h at 40 ℃, fishing out the tea residue for pressing, drying the pressed tea residue until the water content is 5%, collecting the liquid flowing out from the pressing, concentrating the liquid until 50% of the weight of the liquid is used as re-extraction liquid, and concentrating the extraction liquid until 30% of the weight of the extraction liquid is used as primary extraction liquid;

mixing the primary extract and the secondary extract, filtering to remove floating slag in the mixed solution, adding dextrin accounting for 3% of the mixed solution by weight, uniformly stirring, and spray drying to obtain the black tea powder.

Example 6

As shown in fig. 1-2, the present embodiment provides the steam extraction apparatus of embodiments 1-3, which includes an extraction box 1, and a carrying frame 2 disposed in the extraction box 1 in a drawing and inserting manner, and the carrying frame 2 is inserted into the extraction box 1 to divide the extraction box 1 into an upper portion and a lower portion, wherein a steel mesh 3 is fixedly connected to the bottom of the carrying frame 2, and the steel mesh 3 has dense meshes to ensure that the tea leaves do not move downward with the steam during extraction;

the steam extraction device also comprises an air inlet pipe 4 and a condensation component which are respectively and fixedly connected with the upper end and the lower end of the extraction box 1.

In the embodiment, during extraction, dried tea leaves are loaded into the carrying frame 2, the carrying frame 2 is inserted into the extraction box 1, high-temperature steam is introduced into the extraction box 1 through the air inlet pipe 4, and the steam downwards passes through the tea leaves and the steel mesh 3 to enter the condensation assembly and is recovered after condensation;

particularly, steam moves downwards from the tea-leaves top, takes out the remaining effective substance in the tea-leaves more easily, and simultaneously, the condensation subassembly sets up the below at extraction box 1 for certain resistance has when steam flees downwards, can fully contact with the condensing medium in the condensation subassembly, improves condensation efficiency.

Preferably, the condensation assembly comprises a condensation cylinder 5, the upper end of which is fixedly connected with the extraction box 1, and the lower end of the condensation cylinder 5 is fixedly connected with a collection box 6;

the condensation component also comprises a spiral condensation pipe 7 arranged in the condensation cylinder 5, the upper end of the condensation pipe 7 is communicated with the extraction box 1, and the lower end of the condensation pipe 7 is communicated with the collection box 6;

the condensing cylinder 5 is also fixedly connected with a water outlet pipe 8 and a water inlet pipe 9 which are positioned at the upper end and the lower end of the condensing cylinder, cooling water is led in from the lower end of the condensing cylinder 5 through the water inlet pipe 9, the cooling water goes upward and is led out from the water outlet pipe 8 above, the steam in the condensing pipe 7 is condensed in the upward process, and condensed water generated by condensation enters the collecting box 6 below from the lower end of the condensing pipe 7.

Preferably, two mounting plates 10 positioned at the upper end and the lower end of the condensation cylinder 5 are further installed in the condensation cylinder 5, and two ends of the condensation cylinder 5 are respectively installed on the two mounting plates 10;

the water inlet pipe 9 and the water outlet pipe 8 are located between the two mounting plates 10, the mounting plates 10 enable the condenser pipe 7 to be mounted more stably, and meanwhile cooling water is prevented from entering the condenser box or the collecting box 6.

In embodiments 1 to 5, the concentration includes one or more of fine filtration, ultrafiltration, membrane concentration, and vacuum concentration.

The tea leaves produced in examples 1 to 5 and the black tea powder obtained were subjected to experimental analysis, and the results are shown in tables 1 and 2 below:

table 1: tea leaves

Examples	Phenolic compounds%	Purine bases%	Amino acid%	Water content%
					1	0.58	0.08	0.3	5.2
2	0.61	0.06	0.27	5.5
					3	0.52	0.09	0.26	5.6
4	2.5	0.29	2.1	5.2
					5	1.3	0.18	1.2	5.5

Note: before the test, the tea leaves are uniformly dried until the water content is 5-6%.

Table 2: black tea powder

Examples	Phenolic compounds%	Purine bases%	Amino acid%	Water content%
					1	31.5	2.5	3.11	3.5
2	32.1	2.61	3.08	3.6
					3	30.8	2.53	3.12	3.5
4	18.1	1.42	2.11	3.5
					5	23.4	1.95	2.52	3.6

In table 1 above, the residues of the detected components (phenolic substances, purine bases, amino acids) in the tea leaves provided in examples 1 to 3 are all at a low level, which is much lower than those in examples 4 and 5, and it is demonstrated that the production process provided by the present application can extract the effective components in the tea leaves (tea leaves) to the maximum extent;

as can be seen from the data in table 2, the detected components (phenolic substances, purine base substances, amino acid substances) of the black tea powder provided in examples 1 to 3 are higher than those in examples 4 and 5, which indicates that the production process provided by the application can enable more extracted effective components to be retained in the product (black tea powder), and improve the quality of the product;

meanwhile, table 1 and table 2 show that the process has no significant effect on the moisture content of the tea leaves and black tea powder.

Finally, the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting, although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all of them should be covered in the claims of the present invention.

Claims

1. A process for producing black tea powder by dry tea mixed fermentation is characterized by comprising the following steps:

2. The process for producing black tea powder by dry tea mixed fermentation according to claim 1, wherein the fermentation conditions in S1 are: the temperature is 50-60 ℃, and the time is 6-8 h;

3. The process for producing black tea powder by dry tea mixed fermentation according to claim 2, wherein the concentration comprises one or more of fine filtration, ultrafiltration, membrane concentration and vacuum concentration.

4. The process for producing powdered black tea by dry tea mixed fermentation as claimed in claim 3, wherein the steam used in the steam extraction in S2 is derived from the excess liquid obtained by concentration.

5. The process for producing black tea powder through dry tea mixed fermentation according to claim 1, wherein the water content of the black tea powder is 3-4%.

6. The process for producing black tea powder by dry tea mixed fermentation as claimed in claim 1, wherein the steam extraction is performed by passing steam from above the material downward through the material.

7. A steam extraction device for realizing steam extraction in any one of claims 1 to 6, which is characterized by comprising an extraction box and a carrying frame arranged in the extraction box in a drawing and inserting manner, wherein the carrying frame is inserted into the extraction box and then divides the extraction box into an upper part and a lower part, wherein the bottom of the carrying frame is fixedly connected with a steel mesh;

still including fixed connection respectively intake pipe and condensation subassembly in extraction box upper end and lower extreme.

8. The steam extraction apparatus of claim 7, wherein the condensing assembly comprises a condensing drum having an upper end fixedly connected to the extraction tank, and a collecting tank fixedly connected to a lower end of the condensing drum;

9. The steam extraction apparatus as claimed in claim 8, wherein the condensation cylinder further comprises two mounting plates disposed at upper and lower ends thereof, and the two ends of the condensation cylinder are respectively mounted on the two mounting plates;

the inlet tube with the outlet pipe is located two between the mounting panel.