White tea fused with active ingredients and aroma components of reed leaves and processing method of white tea

Abstract

The invention relates to the field of tea processing, in particular to white tea fused with reed leaf active ingredients and aroma components and a processing method of the white tea. The processing method of the white tea comprises the following steps: (1) preparing reed leaf powder; (2) synergistic extraction; (3) vacuum concentration; (4) dipping and transferring: mixing white tea with the reed leaf concentrated solution prepared in the step (3), and carrying out vacuumizing dipping treatment to obtain a white tea mixture; and (5) dynamic baking. The white tea and the processing method thereof have the beneficial effects that the white tea integrating the active ingredients and the aroma components of the reed leaves and the processing method of the white tea are provided, and the processing method establishes a process chain of physical field wall breaking, vacuum impregnation migration and thermal shaping; finally, the compound functional white tea product which has the background flavor of the white tea and the characteristic fragrance of the reed leaves and is high in biological value is prepared. The method can effectively solve the problems of singleness of flavor and health-care efficacy of white tea products and waste of reed leaf resources in the background technology.

Description

Technical Field

[0001] The present invention relates to the field of tea processing, and in particular to white tea blended with active ingredients and aromatic components of rice dumplings and a processing method thereof. Background Art

[0002] White tea, a representative of slightly fermented teas, is one of my country's six traditional teas, primarily produced in Zhenghe and Fuding, Fujian. Currently, Zhenghe's white tea offerings are primarily classic varieties like Silver Needle and White Peony. These products offer relatively limited aromas and health benefits, failing to meet market demand for diverse flavors and complex health benefits. As consumers' interest in distinctive flavors and health benefits continues to grow, there's an urgent need to develop white tea products that combine novel aromas with multiple health benefits through technological innovation, thereby expanding market share and enhancing product competitiveness.

[0003] Modern research indicates that zongzi leaves are rich in flavonoids, polyphenols, and volatile aromatic compounds, exhibiting significant antioxidant, antibacterial, and heat-clearing and dampness-removing properties. The Compendium of Materia Medica also states that zongzi leaves are "mild in nature and sweet in taste, and can relieve summer heat, promote urination, and eliminate stagnation." Traditionally, their decoctions have been widely used among the people to treat damp-heat constitutions. However, in traditional food processing, zongzi leaves are often discarded or incinerated after use as wrapping materials, resulting in both resource waste and environmental pollution. While some new products using zongzi leaves have emerged in China, their market share remains low. However, there are no reports on the development of products combining the active ingredients found in discarded zongzi leaves with white tea.

[0004] To further expand the white tea market and meet the needs of diverse consumers, particularly those with specific flavor preferences and a higher demand for health benefits, white tea products are increasingly diversified, with new flavors and products offering enhanced health benefits. Consequently, there is an urgent need to innovate processing technologies to produce innovative white tea products with new flavors, new forms, and enhanced health benefits, catering to evolving market demands with a more diverse range of styles. Furthermore, effective utilization of zongzi leaves, increasing the extraction rate of active ingredients from these leaves, and integrating these ingredients with white tea to create new white tea products with synergistic benefits are both hot topics and challenges in current research. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a white tea processing method that integrates the active ingredients and aromatic components of zongzi leaves, so as to solve the technical problems in the prior art that white tea products have a single aroma, limited health benefits and the zongzi leaf resources are not fully utilized.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: providing a white tea processing method that integrates the active ingredients of rice dumplings and the aromatic components, comprising the following steps: (1) Preparation of Zongzi leaf powder: Dry and crush the Zongzi leaves to obtain the Zongzi leaf active matrix; (2) Synergistic extraction: taking the active matrix of the rice dumpling leaves prepared in step (1), adding water and performing pulsed electric field pretreatment and ultrasonic pretreatment to obtain a synergistic treatment solution; (3) Concentrating under reduced pressure: The co-processing liquid obtained in step (2) is concentrated under reduced pressure to obtain a rice dumpling leaf concentrate; (4) Immersion transfer: mixing the white tea with the rice dumpling leaf concentrate obtained in step (3), and performing a vacuum immersion treatment to obtain a white tea mixture; (5) Dynamic baking: The white tea mixture obtained in step (4) is subjected to multi-gradient temperature-controlled baking to finally obtain white tea that combines the active ingredients of the rice dumplings and the aromatic ingredients.

[0007] Another technical solution provided by the present invention is: providing a white tea containing the active ingredients and aromatic components of rice dumplings leaves, which is prepared by the above-mentioned white tea processing method containing the active ingredients and aromatic components of rice dumplings leaves.

[0008] The beneficial effects of the present invention are as follows: the present invention provides a white tea integrating active ingredients and aromatic components of zongzi leaves and a processing method thereof, wherein the processing method significantly improves the sensory quality of the zongzi leaf fragrant white tea product by establishing a process chain of "physical field wall breaking-vacuum impregnation migration-thermal shaping", and increases the content of biochemical components such as total water extract, flavonoids, amino acids, and total phenols, while introducing effective ingredients such as usnic acid, chelerythrine, and hawthorn acid as well as aroma components such as theaspirane, jasmine lactone, and β-ionone, giving the white tea a unique fragrance, and providing an important chemical substance basis for the potential health care functions and unique flavor quality of the zongzi leaf fragrant white tea.

[0009] Among them, a green and efficient extraction technology assisted by pulsed electric field coupled ultrasound is used to carry out targeted enrichment of flavonoids, polysaccharides and volatile aromatic components in zongzi leaves, and an innovative vacuum impregnation process is introduced to use the negative pressure osmosis principle to accurately introduce the active substances in the zongzi leaf extract concentrate into the intercellular space of white tea, and construct a micro-area embedding system. After dynamic baking treatment, multi-stage variable temperature control technology combined with continuous turning mass transfer is used to achieve water gradient removal, thermal stabilization of active ingredients and molecular rearrangement of aroma substances, and finally a composite functional white tea product with both the basic flavor of white tea and the characteristic aroma of zongzi leaves and high biological efficacy is obtained. This method can effectively solve the problems of the single flavor and health care efficacy of white tea products and the waste of zongzi leaf resources in the background technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a PCA graph (positive and negative ion modes) of liquid chromatography-mass spectrometry (LC-MS) evaluation of Zongyexiang white tea and raw white tea in Example 4 of a specific embodiment of the present invention; Figure 2OPLS-DA and permutation test diagram (positive ion mode) of liquid chromatography-mass spectrometry (LC-MS) evaluation of Zongyexiang white tea and raw material white tea in Example 4 of a specific embodiment of the present invention; Figure 3 OPLS-DA and permutation test diagram (negative ion mode) of liquid chromatography-mass spectrometry (LC-MS) evaluation of Zongyexiang white tea and raw material white tea in Example 4 of a specific embodiment of the present invention; Figure 4 This is a cluster heat map of non-volatile differential components of Example 4 of a specific embodiment of the present invention and a PCA map of the evaluation of Zongyexiang white tea and raw material white tea by gas chromatography-mass spectrometry; Figure 5 OPLS-DA diagram and permutation test diagram of evaluating Zongyexiang white tea and raw material white tea by gas chromatography-mass spectrometry in Example 4 of a specific embodiment of the present invention; Figure 6 It is a cluster heat map of the volatile difference components of Example 4 according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0011] To illustrate the technical content, achieved objectives and effects of the present invention in detail, the following description is given in conjunction with the embodiments and accompanying drawings.

[0012] The invention of this application is: 1. The present invention is based on a pulsed electric field combined with ultrasound-assisted extraction technology. The electroporation effect of the pulsed electric field is used to disrupt the cellular structure of the zongzi leaves, promoting the release of active substances therein. Simultaneously, ultrasound is used to assist the extraction, utilizing the cavitation effect generated by mechanical vibration to further accelerate the dissolution of the target extract through the channels formed by the pulsed electric field, thereby significantly improving the extraction rate of the active ingredients in the zongzi leaves. This combined extraction technology has the advantages of being safe, harmless, low in energy consumption, high in extraction rate, uniform in distribution, and able to effectively retain the original nutrients of the substance.

[0013] 2. The present invention involves immersing white tea leaves in a concentrated solution of zongzi leaves under vacuum conditions. The vacuum environment significantly reduces atmospheric pressure's resistance to liquid penetration, promoting rapid and deep penetration of the concentrated solution into the white tea leaves. Simultaneously, the vacuum environment lowers the boiling point of the liquid, accelerating the release and transfer of volatile aroma components from the concentrated solution. This method allows the white tea to more comprehensively and evenly absorb the aroma and therapeutic ingredients from the zongzi leaves, significantly enhancing its flavor quality and health benefits.

[0014] 3. This dynamic baking process utilizes precise three-stage temperature control, combined with physical field-assisted technology, to implement a gradient cooling strategy during the Zong Ye Xiang Bai Cha shaping phase. This effectively preserves the volatile aroma components formed by the Zong Ye concentrate infusion while maintaining stable quality characteristics through secondary baking the following day. Furthermore, the synergistic application of three-dimensional oscillation and infrared monitoring technology effectively addresses the uneven heating problem present in traditional static baking, significantly improving product quality.

[0015] 4. The present invention achieves a synergistic effect of white tea and zong leaves by organically integrating the active ingredients of zong leaves with white tea, overcoming the shortcomings of traditional white tea products with a single flavor and single health benefits, and meeting consumers' demand for multifunctional health beverages. 5. The process of the present invention is simple and controllable, easy to operate, and easy to industrialize. It can effectively expand the product line of white tea, increase the market competitiveness of white tea, and provide new ideas for the sustainable development of the white tea industry.

[0016] The present invention provides a method for processing white tea by integrating active ingredients of rice dumplings and leaves with aromatic ingredients, comprising the following steps: (1) Preparation of Zongzi leaf powder: Dry and crush the Zongzi leaves to obtain the Zongzi leaf active matrix; (2) Synergistic extraction: taking the active matrix of the rice dumpling leaves prepared in step (1), adding water and performing pulsed electric field pretreatment and ultrasonic pretreatment to obtain a synergistic treatment solution; (3) Concentrating under reduced pressure: The co-processing liquid obtained in step (2) is concentrated under reduced pressure to obtain a rice dumpling leaf concentrate; (4) Immersion transfer: mixing the white tea with the rice dumpling leaf concentrate obtained in step (3), and performing a vacuum immersion treatment to obtain a white tea mixture; (5) Dynamic baking: The white tea mixture obtained in step (4) is subjected to multi-gradient temperature control baking to finally obtain white tea that combines the active ingredients of the zongzi leaves and the aromatic components. Furthermore, in the above-mentioned white tea processing method that combines the active ingredients of the zongzi leaves and the aromatic components, Furthermore, in the above-mentioned white tea processing method integrating the active ingredients of rice dumplings and the aromatic ingredients, the pulsed electric field pretreatment parameters in step (2) are: electric field intensity 5-15 kV / cm, pulse number 30-90 times, pulse width 10-100 μs; Furthermore, in the above-mentioned white tea processing method integrating the active ingredients of rice dumplings and the aromatic ingredients, the ultrasonic pretreatment parameters in step (2) are: ultrasonic power 200~500 W, ultrasonic time 20~60 min, and ultrasonic temperature 30~90°C.

[0017] From the above description, it can be seen that by limiting the synergistic range of the pulsed electric field and ultrasonic parameters, while ensuring sufficient cell wall rupture, the damage of heat-sensitive components caused by high temperature is avoided. Through the coupling of dual physical fields, the extraction rate of active substances is improved and energy consumption is reduced.

[0018] Furthermore, in the above-mentioned white tea processing method integrating active ingredients and aromatic components of rice dumpling leaves, the rice dumpling leaf extract in step (3) is concentrated to 10%-30% of the original volume.

[0019] From the above description, it can be seen that after concentration, the concentration of active ingredients is increased to the adsorption threshold of white tea, avoiding the deterioration of texture caused by excessive moisture absorption of white tea during the soaking process.

[0020] Furthermore, in the above-mentioned method for processing white tea by integrating the active ingredients and aromatic components of rice dumplings, the white tea in step (5) is Zhenghe Shoumei white tea.

[0021] From the above description, it can be seen that the texture characteristics of the coarse old leaves of Zhenghe white tea Shoumei can load more Zongye leaf extract (the adsorption amount is higher than that of Yinzhen, etc.).

[0022] Furthermore, in the above-mentioned white tea processing method integrating the active ingredients of rice dumplings and the aromatic ingredients, the vacuum impregnation treatment parameters in step (5) are: vacuum degree 0.06~0.12 MPa, temperature 60~90℃, and impregnation time 20~30 min.

[0023] From the above description, it can be seen that the above setting promotes the migration of active ingredients and aromatic substances in the rice dumplings into the interior of the white tea, reduces the boiling point of the liquid to accelerate the migration of aromatic components, and at the same time avoids the oxidation loss of white tea polyphenols caused by high temperature.

[0024] Furthermore, in the above-mentioned method for processing white tea that integrates the active ingredients of rice dumplings and the aromatic ingredients, after breaking the vacuum in step (5), the white tea mixture is further immersed at normal pressure for 10 minutes.

[0025] From the above description, it can be seen that by setting a normal pressure equilibrium stage, the balance of material exchange inside and outside the cells is achieved through pressure difference driving, which solves the problem of local concentration gradient imbalance caused by simple vacuum treatment and improves the uniformity of distribution of active ingredients.

[0026] Furthermore, in the above-mentioned white tea processing method integrating the active ingredients and aromatic components of rice dumplings, the multi-gradient cooling and temperature-controlled baking in step (5) is carried out in three stages: in the first stage, the initial shaping baking is carried out at 80-90°C for 0.5-1 h, during which the robotic arm is turned every 10 minutes; in the second stage, the temperature is lowered to 70-75°C for continuous baking for 1.5-2.5 h, and the three-dimensional oscillation device is simultaneously turned on to realize dynamic heating of the material; in the third stage, after the baked material is spread to room temperature, it is slowly baked at 55-65°C for 0.4-0.6 h the next day, and the temperature and humidity distribution on the surface of the tea leaves is monitored in real time by an infrared thermal imaging system during the baking process, and the hot air circulation rate is adjusted to reduce the moisture content to 5.5±0.5%.

[0027] Furthermore, in the above-mentioned white tea processing method that integrates the active ingredients of rice dumplings and the aromatic ingredients, the white tea processing method is specifically as follows: (1) Preparation of Zongzi leaf powder: Select Zongzi leaves that are free of pests and diseases, wash them with clean water and drain them, dry them in a 60°C oven for 5 h, grind them into ultrafine powder, and pass them through a 60-mesh sieve to obtain the Zongzi leaf active matrix; (2) Synergistic extraction: Take the active matrix of rice dumplings prepared in step (1), add water and mix well, put it into the extraction treatment chamber of the pulse electric field equipment, set the electric field intensity to 5 kV / cm, the number of pulses to 30 times, and the pulse width to 20 μs, and perform pulse electric field treatment to obtain a pulse treatment liquid; then take the pulse treatment liquid and place it in an ultrasonic device, set the ultrasonic power to 250 W, the ultrasonic time to 30 min, and the ultrasonic temperature to 40°C, and perform ultrasonic extraction to obtain a synergistic treatment liquid; (3) vacuum concentration: the co-processed liquid obtained in step (2) was filtered and placed in a vacuum concentration tank, and vacuum concentrated at 60° C. to obtain a rice dumpling leaf concentrate with a concentration ratio of 15%; (4) Impregnation transfer: white tea and the zongzi leaf concentrate obtained in step (3) are mixed in a weight ratio of 1:1 to 1:2, preheated to 80 to 90°C, and then placed in a vacuum tank for vacuum impregnation treatment to promote the migration of active ingredients and aromatic substances of the zongzi leaves into the interior of the white tea; the vacuum impregnation treatment parameters are: vacuum degree 0.06 to 0.12 MPa, temperature 60 to 90°C, and impregnation time 20 to 30 min; (5) Dynamic baking: placing the white tea mixture of step (4) in a thermostatically adjustable dynamic baking machine and baking it with multi-gradient temperature control to obtain white tea containing the active ingredients of the rice dumplings and the aromatic ingredients; In step (5), the multi-gradient temperature-controlled baking is carried out in three stages: in the first stage, the initial shaping baking is carried out at 80-90°C for 0.5-1 h, during which the robotic arm is turned every 10 minutes; in the second stage, the temperature is lowered to 70-75°C for continuous baking for 1.5-2.5 h, and the three-dimensional oscillation device is simultaneously turned on to realize dynamic heating of the material; in the third stage, after the baked material is spread to room temperature, it is slowly baked at 55-65°C for 0.4-0.6 h the next day, and the temperature and humidity distribution on the surface of the tea leaves is monitored in real time through an infrared thermal imaging system during the baking process, and the hot air circulation rate is adjusted to reduce the moisture content to 5.5±0.5%.

[0028] The present invention also provides white tea obtained by the above-mentioned white tea processing method for integrating the active ingredients and aromatic components of rice dumplings leaves.

[0029] Example 1 A method for processing white tea by integrating active ingredients of rice dumplings and aromatic ingredients, comprising the following steps: (1) Raw material pretreatment: Select pest-free zongzi leaves, wash them with clean water and drain them, dry them in a 60°C oven for 5 h, grind them into ultrafine powder and pass them through a 60-mesh sieve to obtain the zongzi leaf active matrix; (2) Synergistic extraction: Take the active matrix of rice dumplings leaves prepared in step (1), add water and mix well, put it into the extraction treatment chamber of the pulse electric field equipment, set the electric field intensity to 5 kV / cm, the number of pulses to 30 times, and the pulse width to 20 μs, and perform pulse electric field treatment to obtain a pulse treatment liquid; then take the pulse treatment liquid and place it in an ultrasonic device, set the ultrasonic power to 250 W, the ultrasonic time to 30 min, and the ultrasonic temperature to 40°C, and perform ultrasonic extraction to obtain a pulse-ultrasonic synergistic treatment liquid; (3) vacuum concentration: the pulse-ultrasound co-processed liquid obtained in step (2) was filtered and placed in a vacuum concentration tank, and vacuum concentrated at 60° C. to obtain a rice dumpling leaf concentrate with a concentration ratio of 15%; (4) Immersion transfer: Zhenghe white tea and zongzi concentrate were mixed in a weight ratio of 1:1, preheated to 80-90°C, and then placed in a vacuum tank for vacuum immersion treatment. The vacuum degree was set to 0.06 MPa, the temperature was set to 65°C, and the immersion time was set to 20 min. After breaking the vacuum, the white tea mixture was immersed for another 10 min at normal pressure to promote further migration of the components. (5) Dynamic baking: The white tea mixture treated in step (4) is placed in a temperature-adjustable dynamic baking machine. In the first stage, the initial shaping baking is carried out at 80°C for 1 hour, during which the robotic arm is turned every 10 minutes to ensure uniform heating; in the second stage, the temperature is lowered to 70°C and the baking is continued for 2.5 hours, and the three-dimensional oscillation device is simultaneously turned on to realize dynamic heating of the material; in the third stage, the baked material is spread out to room temperature and then slowly baked at 55°C for 0.6 hours the next day. During the baking process, the temperature and humidity distribution on the surface of the tea leaves is monitored in real time by an infrared thermal imaging system, and the hot air circulation rate is adjusted to reduce the moisture content to 5.5±0.5%, thereby producing a white tea product with the aroma of rice dumplings and health benefits.

[0030] Example 2 A method for processing white tea by integrating active ingredients of rice dumplings and aromatic ingredients, comprising the following steps: (1) Raw material pretreatment: Select pest-free zongzi leaves, wash them with clean water and drain them, dry them in a 60°C oven for 5 h, grind them into ultrafine powder and pass them through a 60-mesh sieve to obtain the zongzi leaf active matrix; (2) Synergistic extraction: Take the active matrix of rice dumplings prepared in step (1), add water and mix well, put it into the extraction treatment chamber of the pulse electric field equipment, set the electric field intensity to 15 kV / cm, the number of pulses to 90 times, and the pulse width to 80 μs, and perform pulse electric field treatment to obtain a pulse treatment liquid; then take the pulse treatment liquid and place it in an ultrasonic device, set the ultrasonic power to 450 W, the ultrasonic time to 50 min, and the ultrasonic temperature to 80°C, and perform ultrasonic extraction to obtain a pulse-ultrasonic synergistic treatment liquid; (3) vacuum concentration: the pulse-ultrasound co-processed liquid obtained in step (2) is filtered and placed in a vacuum concentration tank, and vacuum concentrated at 60° C. to obtain a rice dumpling leaf concentrate with a concentration ratio of 25%; (4) Impregnation transfer: Mix Zhenghe white tea and Zongye concentrate in a weight ratio of 1:1.2, preheat to 80-90°C, and place in a vacuum tank for vacuum impregnation. Set the vacuum degree to 0.12 MPa, temperature to 85°C, and impregnation time to 30 min. After breaking the vacuum, continue impregnating the white tea mixture at normal pressure for 10 min. (5) Dynamic baking: The white tea mixture treated in step (4) is placed in a temperature-adjustable dynamic baking machine. In the first stage, the initial shaping baking is carried out at 90°C for 0.5 h, during which the robotic arm is turned every 10 minutes to ensure uniform heating; in the second stage, the temperature is lowered to 75°C and the baking is continued for 2 h, and the three-dimensional oscillation device is simultaneously turned on to realize dynamic heating of the material; in the third stage, the baked material is spread out to room temperature and then slowly baked at 65°C for 0.4 h the next day. During the baking process, the temperature and humidity distribution on the surface of the tea leaves is monitored in real time by an infrared thermal imaging system, and the hot air circulation rate is adjusted to reduce the moisture content to 5.5±0.5%, thereby producing a white tea product with the aroma of rice dumplings and health benefits.

[0031] Example 3 A method for processing white tea by integrating active ingredients of rice dumplings and aromatic ingredients, comprising the following steps: (1) Raw material pretreatment: Select pest-free zongzi leaves, wash them with clean water and drain them, dry them in a 60°C oven for 5 h, grind them into ultrafine powder and pass them through a 60-mesh sieve to obtain the zongzi leaf active matrix; (2) Synergistic extraction: Take the active matrix of rice dumplings prepared in step (1), add water and mix well, put it into the extraction treatment chamber of the pulse electric field equipment, set the electric field intensity to 10 kV / cm, the number of pulses to 60 times, and the pulse width to 50 μs, obtain a pulse treatment liquid, and perform pulse electric field treatment to obtain a pulse treatment liquid. Subsequently, take the pulse treatment liquid and place it in an ultrasonic device for ultrasonic treatment, set the ultrasonic power to 350 W, the ultrasonic time to 40 min, and the ultrasonic temperature to 60°C, to obtain a pulse-ultrasonic synergistic treatment liquid; (3) vacuum concentration: the pulse-ultrasound co-processed liquid obtained in step (2) is filtered and placed in a vacuum concentration tank, and vacuum concentrated at 60° C. to obtain a rice dumpling leaf concentrate with a concentration ratio of 20%; (4) Impregnation transfer: Mix Zhenghe white tea and Zongye concentrate in a weight ratio of 1:1.5, preheat to 80-90°C, and place in a vacuum tank for vacuum impregnation. Set the vacuum degree to 0.09 MPa, temperature to 75°C, and impregnation time to 25 min. After breaking the vacuum, continue impregnating the white tea mixture at normal pressure for 10 min. (5) Dynamic baking: The white tea mixture treated in step (4) is placed in a temperature-adjustable dynamic baking machine. In the first stage, the initial shaping baking is carried out at 85°C for 0.8 h, during which the robotic arm is turned every 10 minutes to ensure uniform heating; in the second stage, the temperature is lowered to 73°C and the baking is continued for 2 h, and the three-dimensional oscillation device is simultaneously turned on to realize dynamic heating of the material; in the third stage, the baked material is spread out to room temperature and then slowly baked at 60°C for 0.5 h the next day. During the baking process, the temperature and humidity distribution on the surface of the tea leaves is monitored in real time by an infrared thermal imaging system, and the hot air circulation rate is adjusted to reduce the moisture content to 5.5±0.5%, thereby producing a white tea product with the aroma of rice dumplings and health benefits.

[0032] Quality comparison and analysis of embodiment 4 Zongyexiang white tea and raw material white tea The white tea treated in Example 3, which has relatively better conditions among the above Examples 1-3, was selected as the experimental sample, and the raw white tea that had not been soaked in the zongzi leaf concentrate was used as the control sample. The quality differences between the zongzi leaf-scented white tea and the raw white tea were comprehensively evaluated from three dimensions: sensory evaluation, biochemical composition and non-targeted metabolomics.

[0033] 4.1 Sensory Evaluation The sensory evaluation was conducted by six professionals (three men and three women) in accordance with the national standard "GB / T 23776-2018" (Tea Sensory Evaluation Method). A 3.0 g sample was weighed and placed in a covered bowl. Boiling water was added at a tea-to-water ratio of 1:50 g / mL. After a 5-minute timer, the tea was brewed in the order of infusion. The tea samples were evaluated for their tea color, tea leaves, aroma, and flavor. The scores were weighted on a 100-point scale, with tea appearance accounting for 25%, tea color for 10%, aroma for 25%, flavor for 30%, and tea leaves for 10%. The final sensory score was calculated (see Table 1 for details).

[0034] Table 1 Sensory evaluation results of Zongye-scented white tea and raw white tea As shown in Table 1, the scores of the rice dumpling leaf fragrant white tea prepared by the present invention in the sensory evaluation are all higher than those of the raw white tea. The scores of appearance, soup color and leaf bottom are similar, and no obvious difference is shown. However, the improvement in the two high-weight indicators of aroma and taste is particularly obvious, which is specifically manifested in that the rice dumpling leaf fragrance is obvious, mellow and rich in layers, resulting in a significant gap in sensory quality between the rice dumpling leaf fragrant white tea and the raw white tea.

[0035] 4.2 Determination of biochemical components With reference to national standards such as GB / T 8313-2018 “Determination of tea polyphenols and catechins in tea”, GB / T 8312-2013 “Determination of caffeine in tea”, GB / T 20574-2006 “Determination of total flavonoids in propolis”, GB / T 8314-2013 “Determination of total free amino acids in tea”, GB / T 15672-2009 “Determination of total sugar content in edible fungi” and GB / T 8305-2013 “Determination of tea water extract”, the contents of tea polyphenols, caffeine, total flavonoids, amino acids, total sugars and water extract in tea samples were tested respectively. The results are shown in Table 2.

[0036] Table 2 Comparison of the main biochemical components of Zongyexiang white tea and raw white tea Note: Different lowercase letters in the same column indicate significant differences between groups ( P <0.05).

[0037] As shown in Table 2, the water extract, flavonoids, amino acids, total phenols, and polysaccharide contents of the zongzi-leaf-scented white tea prepared according to the present invention were significantly increased compared to the raw white tea, while the caffeine content remained unchanged. This may be attributed to the white tea effectively adsorbing most of the substances contained in the zongzi-leaf extract. During the drying process, these substances undergo chemical reactions, oxidizing the sugars in the zongzi-leaf extract into sugar acids, which undergo saccharification reactions and generate organic acids such as ferulic acid. These organic acids, when dissolved in water, not only contribute to the determination of total phenols and polysaccharides but also alter the pH of the tea leaves, thereby affecting the dissolution of amino acids. In contrast, caffeine, a stable tea alkaloid, exhibits no significant changes during processing, as its biosynthesis is primarily regulated by endogenous factors within the tea leaves (such as precursors and enzymes). The content and composition of active ingredients in tea are key factors in determining its quality and function. The significant increase in the content of water extract, flavonoids, amino acids, total phenols and polysaccharides in Zongyexiang white tea provides a solid material basis for the formation of its unique sensory qualities such as soup color, taste and aroma.

[0038] 4.3 Determination of non-volatile components in tea based on non-targeted metabolomics (1) Extraction of tea metabolites Tea samples were ground into powder and passed through a 100-mesh sieve to collect the fine powder. An appropriate amount of powder was accurately weighed and placed in a 2 mL centrifuge tube. 600 µL of a methanol solution containing 2-chloro-L-phenylalanine was then added and vortexed for 30 seconds. 100 mg of glass beads were then added, and the tube was placed in a tissue grinder and ground at 60 Hz for 90 seconds. The tube was then ultrasonicated at room temperature for 15 minutes. Finally, the tube was centrifuged at 12,000 rpm and 4°C for 10 minutes. The supernatant was filtered through a 0.22 μm filter and transferred to a vial for LC-MS analysis.

[0039] (2) Tea sample testing and analysis Chromatographic conditions: An ACQUITY UPLC® HSST3 column (2.1 × 150 mm, 1.8 µm) was used at a flow rate of 0.25 mL / min, a column temperature of 40°C, and an injection volume of 2 µL. The mobile phase consisted of 0.1% formic acid in acetonitrile and 0.1% formic acid in water.

[0040] Mass spectrometry conditions: electrospray ionization (ESI) source, acquisition in positive and negative ion modes. Spray voltage: 3.50 kV in positive ion mode, -2.50 kV in negative ion mode, auxiliary gas flow rate: 10 arb, sheath gas flow rate: 30 arb, capillary temperature: 325°C.

[0041] 4.4 Determination of tea volatile components based on non-targeted metabolomics (1) Extraction of tea metabolites Accurately weigh 0.5 g of tea sample into a 20 mL headspace vial, add 10 μL of internal standard solution, and incubate the sample at 60°C for 10 minutes. Prior to sample adsorption, the SPME tip is conditioned at 270°C for 10 minutes. Subsequently, the conditioned SPME tip is transferred to an incubation chamber and adsorbed at 60°C for 15 minutes. Following adsorption, the SPME tip is transferred to the GC inlet and desorbed at 250°C for 5 minutes. Following injection, the SPME tip is again conditioned at 270°C for 10 minutes. Finally, 10 μL of n-alkane is added to the 20 mL headspace vial, incubated for extraction, and injected.

[0042] (2) Tea sample testing and analysis Chromatographic conditions: A DB-Heavy Wax column (30 m × 250 μm × 0.5 μm, Agilent, USA) was used, with high-purity helium as the carrier gas at a constant flow rate of 1.0 mL / min. The column temperature was initially set at 50°C for 2 min, then increased to 240°C at a rate of 5°C / min and held for 5 min.

[0043] Mass spectrometry conditions: mass spectrometry transfer line temperature of 250 °C, ion source temperature of 250 °C, acquisition rate of 10 spectra / s, electron impact source energy of 70 eV, detector voltage of 1.96 kV, and mass spectrometry scan range of m / z 35-550.

[0044] 4.5 Metabolomics Data Processing and Analysis Multivariate statistical analysis was used to process and analyze the data. First, unsupervised principal component analysis (PCA) was used to comprehensively evaluate the detected metabolites to provide a preliminary understanding of the overall metabolite differences between groups and the degree of variability between samples within groups. Then, supervised orthogonal partial least squares discriminant analysis (OPLS-DA) was used to further evaluate the predictive ability and reliability of the established model. A permutation test was used to internally test the model to avoid overfitting. Furthermore, to more intuitively demonstrate the similarities and differences between samples, cluster heat maps were used to visualize the metabolites.

[0045] 4.5.1 Analysis of non-volatile components in tea leaves based on non-targeted metabolomics Based on the experimental results of non-targeted metabolomics by liquid chromatography-mass spectrometry, principal component analysis of tea metabolites was performed in positive and negative ion modes. Figure 1 In positive ion mode, the variance contributions of the first principal component (PC1) and the second principal component (PC2) were 85.5% and 3.91%, respectively, with a cumulative variance contribution of 89.41%. In negative ion mode, the variance contributions of the first principal component (PC1) and the second principal component (PC2) were 85.3% and 4.23%, respectively, with a cumulative variance contribution of 89.53%. These results demonstrate that PCA in both ion modes effectively captures the majority of metabolite information in the samples. Furthermore, in both positive and negative ion modes, the distances between the Zongyexiang white tea sample points and the raw white tea sample points were significant, indicating significant changes in the non-volatile metabolites of the white tea after infusion with Zongye concentrate.

[0046] To obtain more accurate results, supervised OPLS-DA was used to further analyze the data by amplifying the differences between groups and reducing the differences within groups. Figure 2 and Figure 3 As can be seen, in both positive and negative ion modes, all samples fell within the 95% confidence interval, with Zongyexiang white tea and raw white tea samples located on the right and left sides of the confidence interval, respectively, demonstrating a clear distinction and indicating significant differences in their non-volatile components. Furthermore, cross-validation results showed that the intercept of Q2 with the Y-axis was less than 0, indicating that the constructed model was not overfitting.

[0047] Based on the primary mass spectrometry differential metabolite analysis, the differential ions were analyzed by secondary mass spectrometry. P The value < 0.05 was used as the screening condition, and a total of 188 significantly different metabolites were identified. The differential metabolites were analyzed using cluster heat maps. Figure 4 It can be seen that Zongyexiang white tea and raw white tea can clearly distinguish these 188 significantly different metabolites into two groups, among which the relative contents of 93 components in Zongyexiang white tea are significantly higher than those in raw white tea, while the relative contents of 95 components are significantly lower than those in raw white tea. In order to further clarify the key differential metabolites, more stringent screening conditions were set, namely VIP>1, P <0.001 and FC>1.5, and finally 24 metabolites with significantly higher relative contents than those in raw white tea were identified (see Table 3 for details).

[0048] Table 3 Differential components between Zongyexiang white tea and raw white tea in non-targeted metabolomics Studies have shown that usnic acid, a secondary metabolite of lichens, is widely used in cosmetics, perfumes, and traditional medicines due to its diverse biological activities, including anti-inflammatory, antibacterial, anticancer, and antiviral properties. Chelerythrine is an alkaloid extracted from plant species with diverse biological activities, including anti-inflammatory, anticancer, and antidiabetic properties. β-Caryophyllene is a CB2R inhibitor that can effectively prevent cognitive impairment caused by neuroinflammation. Nootkatone is a natural sesquiterpene extract with multiple beneficial activities, including antibacterial, antioxidant, and anticancer properties. Gibberellic acid A98 is a potent anticancer compound found in targeted medicinal plants that plays a key role in regulating important pathways involved in colon cancer. Maslinic acid is a pentacyclic triterpene acid widely found in natural plants with anticancer, anti-inflammatory, and neuroprotective activities. D-pinitol is a pharmacologically active cycloalanol. Plants rich in D-pinitol are often used in traditional medicine to treat diabetes, inflammation, and cancer.

[0049] In summary, due to the introduction of zongzi leaf concentrate and the synergistic effect of the processing process, zongzi leaf fragrant white tea is significantly enriched with a variety of active metabolites with anti-cancer, anti-inflammatory, anti-diabetic, neuroprotective and metabolic regulatory functions. These main differential metabolites constitute the quality difference between zongzi leaf fragrant white tea and raw white tea, and provide a scientific material basis for its potential health care functions.

[0050] 4.5.2 Analysis of tea volatile components based on non-targeted metabolomics Based on the experimental results of non-targeted metabolomics by GC-MS, a total of 72 volatile compounds were detected in the Zongyexiang white tea and raw white tea samples. By performing principal component analysis on the metabolites of tea samples, such as Figure 4As shown in the figure, the variance contribution rates of the first principal component (PC1) and the second principal component (PC2) were 87.7% and 6.52% respectively, and the cumulative variance contribution rate was 94.22%. The distance between the sample points of the Zongye-scented white tea and the raw white tea sample points was relatively far, indicating that the volatile metabolites in the white tea after being soaked in the Zongye concentrate had changed significantly. Figure 5 As shown in the figure, OPLS-DA analysis yielded two principal components. All samples fell within the 95% confidence interval, with Zongyexiang white tea and raw white tea samples located on the right and left sides of the confidence interval, respectively. This clearly demonstrates a significant difference in volatile components between the two. Cross-validation results show that the intercept of Q2 on the Y-axis is less than 0, indicating that the model is not overfitting.

[0051] The 72 volatile metabolites were normalized and cluster heat maps were drawn to reflect the changing trends of the metabolites. Figure 6 It can be seen that Zongye-scented white tea and raw white tea can clearly distinguish these 72 differential metabolites into two groups. Compared with the raw white tea, 28 differential metabolites were significantly upregulated in Zongyexiang white tea, including: n-butyl acrylate, 5-ethyldecane, 3-methylundecane, toluene, pyrrole-2-carboxaldehyde, theaspirane, 2-acetylpyrrole, jasmone, kadane, jasmine lactone, 4-hydroxy-2,2,6-trimethylcyclohexanone (isomer 1), β-ionone, allo-ocimene (4E,6E), 2,4-di-tert-butylphenol, decanoic acid, p-anisidine, dimethyl disulfide, 3,8-dimethyldecane, 2-methylundecane, cuminol, dimethyl phthalate, 4-(1,1-dimethylpropyl)phenol, indole, acetol, 1,3-trans,5-cis-octatriene, isobutyraldehyde trimer, and 1,2,4,5-tetramethylbenzene. Among them, jasmone, jasmonate, β-ionone, theaspirane, allo-ocimene, and cuminol are aromatic compounds widely used in flavors and fragrances. The increased relative content of these compounds imparts more floral, woody, and herbal aromas to white tea, significantly enhancing the aroma quality of Zongyexiang white tea.

[0052] Further analysis revealed that the significant differences in volatile metabolites between Zongye-scented white tea and raw white tea may be due to the synergistic effect of the migration of natural components from the Zongye leaves and chemical transformations driven by processing conditions (such as esterification, oxidation, and hydrolysis). The unique aromas of Zongye-scented white tea (e.g., woody, herbal, and refreshing) are derived not only from the complementary effects between the Zongye and white tea components but also from the precise control of metabolite production pathways through processing. This mechanism provides an important chemical basis for the unique flavor qualities of Zongye-scented white tea.

[0053] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's description and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for processing white tea by integrating active ingredients of rice dumplings and aromatic components, characterized in that: The following steps are involved: (1) Preparation of Zongzi leaf powder: Dry and crush the Zongzi leaves to obtain the Zongzi leaf active matrix; (2) Synergistic extraction: taking the active matrix of the rice dumpling leaves prepared in step (1), adding water and performing pulsed electric field pretreatment and ultrasonic pretreatment to obtain a synergistic treatment solution; (3) Concentrating under reduced pressure: The co-processing liquid obtained in step (2) is concentrated under reduced pressure to obtain a rice dumpling leaf concentrate; (4) Immersion transfer: mixing the white tea with the rice dumpling leaf concentrate obtained in step (3), and performing a vacuum immersion treatment to obtain a white tea mixture; (5) Dynamic baking: The white tea mixture obtained in step (4) is subjected to multi-gradient temperature-controlled baking to finally obtain white tea that combines the active ingredients of the rice dumplings and the aromatic ingredients.

2. The white tea processing method of claim 1, wherein the white tea processing method comprises the following steps: The pulse electric field pretreatment parameters in step (2) are: electric field intensity 5~15 kV / cm, pulse number 30~90 times, and pulse width 10~100 μs.

3. The white tea processing method of claim 1, wherein the white tea processing method comprises the following steps: The ultrasonic pretreatment parameters in step (2) are: ultrasonic power 200~500 W, ultrasonic time 20~60 min, and ultrasonic temperature 30~90℃.

4. The white tea processing method of claim 1, wherein the white tea processing method comprises the following steps: In step (3), the rice dumpling leaf extract is concentrated to 10%-30% of the original volume.

5. The white tea processing method of claim 1, wherein the white tea processing method comprises the following steps: The white tea described in step (5) is Zhenghe white tea Shoumei.

6. The white tea processing method of claim 1, wherein the white tea processing method comprises the following steps: The vacuum impregnation treatment parameters in step (5) are: vacuum degree 0.06~0.12 MPa, temperature 60~90℃, and impregnation time 20~30 min.

7. The white tea processing method of claim 1, wherein the white tea processing method comprises the following steps: After breaking the vacuum in step (5), the white tea mixture is immersed for 10 minutes under normal pressure.

8. The white tea processing method of claim 1, wherein the white tea processing method comprises the following steps: In step (5), the multi-gradient temperature-controlled baking is carried out in three stages: in the first stage, the initial shaping baking is carried out at 80-90°C for 0.5-1 h, during which the robotic arm is turned every 10 minutes; in the second stage, the temperature is lowered to 70-75°C for continuous baking for 1.5-2.5 h, and the three-dimensional oscillation device is simultaneously turned on to realize dynamic heating of the material; in the third stage, after the baked material is spread to room temperature, it is slowly baked at 55-65°C for 0.4-0.6 h the next day, and the temperature and humidity distribution on the surface of the tea leaves is monitored in real time through an infrared thermal imaging system during the baking process, and the hot air circulation rate is adjusted to reduce the moisture content to 5.5±0.5%.

9. The white tea processing method of claim 1, wherein the white tea processing method comprises the following steps: The white tea processing method is specifically as follows: (1) Preparation of Zongzi leaf powder: Select Zongzi leaves that are free of pests and diseases, wash them with clean water and drain the water, place them in a 60℃ oven to dry for 5 h, grind them into ultrafine powder and pass them through a 60-mesh sieve to obtain the Zongzi leaf active matrix; (2) Synergistic extraction: Take the active matrix of rice dumplings prepared in step (1), add water and mix well, put it into the extraction treatment chamber of the pulse electric field equipment, set the electric field intensity to 5 kV / cm, the number of pulses to 30 times, and the pulse width to 20 μs, and perform pulse electric field treatment to obtain a pulse treatment liquid; then take the pulse treatment liquid and place it in an ultrasonic device, set the ultrasonic power to 250 W, the ultrasonic time to 30 min, and the ultrasonic temperature to 40°C, and perform ultrasonic extraction to obtain a synergistic treatment liquid; (3) vacuum concentration: the co-processed liquid obtained in step (2) was filtered and placed in a vacuum concentration tank, and vacuum concentrated at 60° C. to obtain a rice dumpling leaf concentrate with a concentration ratio of 15%; (4) Impregnation transfer: white tea and the zongzi leaf concentrate obtained in step (3) are mixed in a weight ratio of 1:1 to 1:2, preheated to 80 to 90°C, and then placed in a vacuum tank for vacuum impregnation treatment to promote the migration of active ingredients and aromatic substances of the zongzi leaves into the interior of the white tea; the vacuum impregnation treatment parameters are: vacuum degree 0.06 to 0.12 MPa, temperature 60 to 90°C, and impregnation time 20 to 30 min; (5) Dynamic baking: placing the white tea mixture of step (4) in a thermostatically adjustable dynamic baking machine and baking it with multi-gradient temperature control to obtain white tea containing the active ingredients of the rice dumplings and the aromatic ingredients; In step (5), the multi-gradient temperature-controlled baking is carried out in three stages: in the first stage, the initial shaping baking is carried out at 80-90°C for 0.5-1 h, during which the robotic arm is turned every 10 minutes; in the second stage, the temperature is lowered to 70-75°C for continuous baking for 1.5-2.5 h, and the three-dimensional oscillation device is simultaneously turned on to realize dynamic heating of the material; in the third stage, after the baked material is spread to room temperature, it is slowly baked at 55-65°C for 0.4-0.6 h the next day, and the temperature and humidity distribution on the surface of the tea leaves is monitored in real time through an infrared thermal imaging system during the baking process, and the hot air circulation rate is adjusted to reduce the moisture content to 5.5±0.5%.

10. The white tea obtained by the white tea processing method of fusion of active ingredients of rice dumpling leaves and fragrant ingredients according to any one of claims 1-9 is fusion of active ingredients of rice dumpling leaves and fragrant ingredients.

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