Composite instant tea and its preparation method

Abstract

The application discloses a kind of composite instant tea and preparation method thereof, it is related to the deep processing of medicine and food functional tea drink, plant extract composite formula and instant food preparation technical field.The application contains oleaceae robust ligusticum extract and rhizoma polygonati extract.The preparation method includes: the raw material of robust ligusticum is subjected to double-stage high-temperature fermentation, low-temperature fermentation and high-temperature fermentation of 58~62 ℃ and 83~87 ℃ in turn;the fermentation product is subjected to low-temperature ultrasonic extraction of 40~50 ℃, to obtain first extraction liquid;the raw material of rhizoma polygonati is extracted, to obtain second extraction liquid;after mixing the two extraction liquids, concentrate, then vacuum freeze-drying at-35 ℃ to-45 ℃, to obtain instant tea powder.Through double-stage fermentation, the bitterness of raw material is neutralized, and bitter and astringent substances are degraded, combined with low-temperature extraction and freeze-drying process to retain active ingredients, the obtained product has the advantages of smooth taste, instant without residue, high retention rate of active ingredients, and is suitable for long-term drinking in all seasons.

Description

Technical Field

[0001] This invention relates to the fields of deep processing of functional tea beverages that are both food and medicine, compound formulations of plant extracts, and preparation of instant foods. Specifically, it relates to a compound instant tea and its preparation method. Background Technology

[0002] Ligustrum robustum, belonging to the Oleaceae family, is a native medicinal and edible plant characteristic of the Wujiang River basin in Guizhou Province. Unlike common privet, its leaves are rich in active substances such as privetin, oleanolic acid, and ursolic acid. Traditional Chinese medicine texts record its ability to soothe dryness, regulate the body, and provide gentle nourishment, making it a natural ingredient for health-promoting teas. However, current processing techniques for Ligustrum robustum teas are limited, often employing a single-stage withering and drying process. This has two major drawbacks: firstly, the raw material itself contains cold properties and bitter tannins, resulting in a rough, astringent, and irritating taste when brewed directly, which can easily irritate the spleen and stomach with long-term consumption; secondly, conventional high-temperature processing destroys many heat-sensitive active ingredients, leading to low dissolution rates of effective components and significantly reducing its health benefits.

[0003] Polygonatum is a classic food and medicine ingredient, rich in polysaccharides, various amino acids, and trace elements, possessing the effects of invigorating qi and nourishing yin, as well as warming and tonifying. Currently, commercially available Polygonatum teas generally suffer from problems such as rudimentary raw material processing, strong bitterness, and poor water solubility. Ordinary brewing makes it difficult to extract the effective components. Furthermore, Polygonatum alone is too rich and cloying, while Ligustrum lucidum alone is too mild and moistening. Both have limited effects and suitable occasions when consumed alone, failing to achieve a balanced approach to health maintenance that combines warming and cooling properties with nourishing and tonifying effects.

[0004] Meanwhile, traditional solid tea drinks are mostly in the form of broken tea leaves or coarse powder, which leave residues and dissolve slowly when brewed, resulting in poor portability and drinking experience; ordinary instant teas mostly use high-temperature spray drying process, which causes a large loss of plant active ingredients due to the high temperature environment, and no adaptation or modification has been made for the characteristics of the two raw materials, so it is impossible to balance taste, safety and functionality.

[0005] In summary, the market currently lacks a compound instant tea of ​​Ligustrum lucidum and Polygonatum that balances cold and heat, combines cleansing and nourishing properties, has a mellow taste, retains its active ingredients, dissolves quickly without residue, and can be consumed year-round. Therefore, this invention, with its compound formula and exclusive preparation process, fills a technological gap in the industry. Summary of the Invention

[0006] The purpose of this invention is to provide a compound instant tea and its preparation method to solve the problems of privet-type tea drinks having excessively cold raw materials and a bitter and astringent taste.

[0007] To solve the above problems, the present invention employs the following technical means: A compound instant tea containing extracts of Ligustrum lucidum (Oleaceae family) and Polygonatum sibiricum.

[0008] Preferably, the extract of Ligustrum lucidum (Oleaceae family) is 40-65 parts by weight, and the extract of Polygonatum sibiricum is 25-45 parts by weight.

[0009] Furthermore, by weight, the extract of Ligustrum lucidum (Oleaceae family) is 52 parts, and the extract of Polygonatum sibiricum is 38 parts.

[0010] Furthermore, it also includes water-soluble excipients.

[0011] Furthermore, the water-soluble excipient is one or more of maltodextrin, erythritol, and fructooligosaccharides.

[0012] In addition, a method for preparing the aforementioned compound instant tea includes the following steps: S1. Fermentation treatment of robust Ligustrum lucidum (Oleaceae family) raw materials to obtain fermentation products; S2. Extract the fermentation product to obtain a first extract; S3. Extract the Polygonatum sibiricum raw material to obtain a second extract; S4. Mix the first extract with the second extract to obtain a mixture; S5. The mixture is concentrated and dried to obtain instant tea powder.

[0013] Furthermore, the fermentation process described in step S1 is a two-stage high-temperature fermentation, including a first stage of low-temperature fermentation and a second stage of high-temperature fermentation.

[0014] Furthermore, the first stage of low-temperature fermentation is carried out at a temperature of 58~62℃ for 2.5~3.5 hours; the second stage of high-temperature fermentation is carried out at a temperature of 83~87℃ for 1.5~2.5 hours.

[0015] Furthermore, the extraction described in step S2 is low-temperature ultrasonic extraction, with an extraction temperature of 40~50℃ and an extraction time of 40~60 minutes.

[0016] Furthermore, in step S5, the drying process is vacuum freeze-drying, with a freeze-drying temperature of -35°C to -45°C and a freeze-drying time of 18 to 24 hours.

[0017] The present invention has the following beneficial effects during use: This product is a blend of extracts from Ligustrum lucidum (family Oleaceae) and Polygonatum sibiricum. Ligustrum lucidum is rich in active ingredients such as privetin and oleanolic acid, and has a mild and moisturizing nature; Polygonatum sibiricum is rich in polysaccharides and saponins, and has a warming and tonifying nature. When combined, the mild and moisturizing nature of Ligustrum lucidum neutralizes the richness of Polygonatum sibiricum, while the warming and tonifying properties of Polygonatum sibiricum balance the slightly cold nature of Ligustrum lucidum, resulting in a balanced and mild overall effect. This overcomes the drawbacks of Ligustrum lucidum tea being too cold and potentially damaging to the spleen and stomach, and Polygonatum sibiricum tea being too rich and cloying, making the product suitable for long-term consumption by people with both hot and cold constitutions throughout the year.

[0018] The robust privet raw materials undergo sequential low-temperature fermentation at 58-62℃ and high-temperature fermentation at 83-87℃. The first stage, low-temperature fermentation, activates the endogenous enzyme system of the raw materials, promoting the enzymatic degradation of bitter precursors such as oxalic acid and crude tannins, reducing irritation. The second stage, high-temperature fermentation, denatures proteins and ruptures cell walls, further hydrolyzing the released bound tannins. Simultaneously, the heat alters the molecular conformation, neutralizing the cold nature of the raw materials. This systematically eliminates the bitterness and cold properties of traditional privet tea at a chemical level, resulting in a mellow, fragrant, and sweet-smelling tea that is gentle on the stomach and spleen when consumed on an empty stomach.

[0019] Ultrasonic-assisted countercurrent extraction was employed at 40-50℃, where the ultrasonic cavitation effect accelerated cell wall disruption and the dissolution of active ingredients. The low-temperature environment prevented thermal degradation of heat-sensitive active substances such as privetin, oleanolic acid, and polygonatum polysaccharides. Subsequent vacuum freeze-drying at -35℃ to -45℃ allowed water to sublimate directly in the solid state, preserving the microporous structure formed by ice crystals within the material and ensuring minimal chemical changes to the active ingredients. This resulted in a high retention rate of key active ingredients such as privetin and polygonatum polysaccharides, significantly enhancing the product's functional value.

[0020] During vacuum freeze-drying, the sublimation of internal moisture leaves behind numerous interconnected micropores, resulting in a large specific surface area and high porosity in the final powder. This unique physical structure allows water molecules to rapidly penetrate and wet the powder particles, achieving complete dissolution in room temperature water within 3-5 seconds, without sediment or residue. It can be brewed without hot water, greatly simplifying drinking conditions. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0022] Therefore, the following detailed description of embodiments of the present invention is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other. Example

[0024] Fresh, robust, tender leaves of *Ligustrum lucidum* (privet) from the Wujiang River basin in Guizhou Province were selected, washed, and placed in a constant-temperature fermentation device. First, they were awakened and fermented at 60℃ for 3 hours, then sublimated at 85℃ for 2 hours. After fermentation, purified water was added at a material-to-liquid ratio of 1:10, and the mixture was extracted countercurrently at 45℃ and 300W ultrasonic conditions for 50 minutes. The *Ligustrum lucidum* extract was then collected by filtration. Separately, *Polygonatum sibiricum* (scientifically processed and sun-dried) was pulverized to 50 mesh, and extracted with 8 times the amount of purified water at 80℃ for 2 hours. After centrifugation, the extract was purified by ethanol precipitation, and the purified extract was collected. 52 parts of the *Ligustrum lucidum* extract and 38 parts of the *Polygonatum sibiricum* extract were mixed, and 10 parts of fructooligosaccharides were added. The mixture was vacuum concentrated at 55℃ and -0.09MPa to a solid content of 35%, then freeze-dried at -40℃ for 22 hours. The powder was then pulverized through an 80-mesh sieve to obtain the compound instant tea powder. Example

[0025] The operating steps are the same as in Example 1, except that the temperature of the first stage of the two-stage fermentation is adjusted to 50°C and the temperature of the second stage is adjusted to 75°C. All other conditions remain unchanged. Example

[0026] The operating steps are the same as in Example 1, except that the extraction method for the privet fermentation product is changed to 90°C hot water reflux extraction for 60 minutes instead of low-temperature ultrasonic extraction. All other conditions remain unchanged. Example

[0027] The operating steps are the same as in Example 1, except that vacuum freeze drying is replaced with spray drying with an inlet air temperature of 180°C and an outlet air temperature of 85°C. All other conditions remain unchanged. Example

[0028] The operating steps are the same as in Example 1, except that the two-stage high-temperature fermentation step is omitted, and the fresh privet leaves are directly blanched before extraction. All other conditions remain unchanged. Example

[0029] The operating steps are the same as in Example 1, except that the amount of privet extract is adjusted to 70 parts and the amount of polygonatum extract is adjusted to 20 parts. All other conditions remain unchanged.

[0030] Sensory evaluations were conducted on the products of Examples 1-6. Ten trained tasters used a blind test method to score the products (out of 10 points, with higher scores indicating better taste and less cold stimulation).

[0031]

[0032] Among them, the two-stage fermentation parameters in Example 1 were optimal. When the fermentation temperature was changed as in Example 2, the bitterness and coldness scores decreased significantly, indicating that this specific temperature window is crucial for degrading tannins and neutralizing coldness. In Example 5, after omitting the fermentation step, the product was unbearably bitter and had a strong coldness, indicating that two-stage fermentation is the core process for eliminating raw material defects. In Example 3, although high-temperature extraction resulted in better neutralization of coldness, the bitterness increased because the high temperature destroyed some flavor substances and redissolved impurities. In Example 4, spray drying reduced overall acceptability because the high temperature caused the loss of some active ingredients and reduced powder solubility. In Example 6, after changing the ratio, the proportion of privet was too high, and the coldness increased somewhat.

[0033] Subsequently, the contents of privetin and polygonatum polysaccharide in the products of each embodiment were determined, and the retention rate was calculated based on the theoretical content of fresh raw materials as 100%.

[0034]

[0035] Among them, Example 1 showed the highest retention rate of active ingredients, exceeding 92%. In Example 3, due to high-temperature extraction, a significant amount of heat-sensitive components were lost, resulting in a retention rate of only 54.3% for privetin. In Example 4, the high-temperature environment of spray drying severely damaged the active ingredients, resulting in a retention rate of less than 50%. Although fermentation was omitted in Example 5, low-temperature extraction was used, resulting in a acceptable retention rate of privetin, but the extremely poor taste led to low practical application value.

[0036] Subsequently, the complete dissolution time of each product in room temperature water at 25°C and the presence or absence of residue were tested.

[0037]

[0038] Among them, Examples 1, 2, 5, and 6, which used vacuum freeze-drying, could completely dissolve within seconds without leaving any residue. This is because the porous structure formed by freeze-drying endows the powder with excellent rehydration properties. In contrast, Example 4, which used spray drying, produced dense powder particles, resulting in a slow dissolution rate and precipitation.

[0039] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A compound instant tea, characterized in that, It contains extracts of Ligustrum lucidum (of the Oleaceae family) and Polygonatum sibiricum.

2. The compound instant tea according to claim 1, characterized in that, The extract of Ligustrum lucidum (Oleaceae family) is 40-65 parts by weight, and the extract of Polygonatum sibiricum is 25-45 parts by weight.

3. The compound instant tea according to claim 2, characterized in that, By weight, the extract of Ligustrum lucidum (Oleaceae family) is 52 parts, and the extract of Polygonatum sibiricum is 38 parts.

4. The compound instant tea according to claim 1, characterized in that, It also contains water-soluble excipients.

5. The compound instant tea according to claim 4, characterized in that, The water-soluble excipient is one or more of maltodextrin, erythritol, and fructooligosaccharides.

6. A method for preparing the compound instant tea according to any one of claims 1 to 5, characterized in that, Includes the following steps: S1. Fermentation treatment of robust Ligustrum lucidum (Oleaceae family) raw materials to obtain fermentation products; S2. Extract the fermentation product to obtain a first extract; S3. Extract the Polygonatum sibiricum raw material to obtain a second extract; S4. Mix the first extract with the second extract to obtain a mixture; S5. The mixture is concentrated and dried to obtain instant tea powder.

7. The preparation method according to claim 6, characterized in that, The fermentation process described in step S1 is a two-stage high-temperature fermentation, including a first stage of low-temperature fermentation and a second stage of high-temperature fermentation.

8. The preparation method according to claim 7, characterized in that, The first stage of low-temperature fermentation is carried out at a temperature of 58~62℃ for 2.5~3.5 hours; the second stage of high-temperature fermentation is carried out at a temperature of 83~87℃ for 1.5~2.5 hours.

9. The preparation method according to claim 6, characterized in that, The extraction described in step S2 is low-temperature ultrasonic extraction, with an extraction temperature of 40~50℃ and an extraction time of 40~60 minutes.

10. The preparation method according to claim 6, characterized in that, In step S5, the drying process is vacuum freeze drying, with a freeze drying temperature of -35°C to -45°C and a freeze drying time of 18 to 24 hours.

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