Chinese tea pastry of Wuniu morning tea and preparation method of Chinese tea pastry

Abstract

The invention relates to the technical field of pastries, and provides a Chinese tea pastry of Wuniu morning tea and a preparation method of the Chinese tea pastry. The preparation method of the Chinese tea cake of the Wuniu morning tea comprises the following steps: S100, refining the Wuniu morning tea raw material to obtain Wuniu morning tea powder; s200, mixing the Wuniu morning tea powder, low-gluten flour and pre-gelatinized starch to obtain a dry mixture; s300, performing dough kneading treatment on the dry mixture and enzyme liquid to form dough; s400, wrapping the stuffing into a wrapper made of the dough, and forming to obtain a green body; and S500, performing segmented baking on the green body to obtain the Chinese tea cake of Wuniu morning tea. The Wuniu morning tea powder, the low-gluten flour and the pre-gelatinized starch are prepared into a dry mixture, enzymatic dough kneading is adopted, a segmented baking process is matched, the problem of storage stability of the product is mainly solved, moisture combination and tissue microstructures are improved, and adverse moisture migration and starch aging are inhibited, so that moisture regain and water loss hardening are delayed, and the quality of the product is improved. The sensory acceptable period is kept, the shelf life is prolonged, and the storage and transportation tolerance is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cakes, in particular to a Chinese tea cake and a preparation method thereof. BACKGROUND

[0002] As a characteristic food combining traditional cakes and tea culture, the Chinese tea cake not only carries regional flavors but also meets the needs of the fast-moving consumer goods market for portable instant, Chinese-flavored retail products. With the increasing requirements of the consumer end for flavor stability, taste consistency and ambient circulation, the industrialized production of cakes gradually develops towards functionalization of the formula and controllability of the process.

[0003] The existing Chinese tea cakes generally have the problems of short shelf life and poor storage stability, mainly manifested in the organization densification and taste hardening caused by water migration and starch aging during ambient storage, thereby shortening the sensory acceptable period and reducing the storage and transportation tolerance. The existing formula and one-time high-temperature baking process have limited effect on alleviating the problems.

[0004] Therefore, there is an urgent need for a Chinese tea cake and a preparation method thereof to solve the above problems. SUMMARY

[0005] In view of the above deficiencies in the prior art, the purpose of the present application is to provide a Chinese tea cake of Wuniuzao tea and a preparation method thereof, which uses Wuniuzao tea powder, low-gluten flour and pre-gelatinized starch in combination, and combines enzymatic and face-making processes and segmented baking processes to improve the water binding state and microstructure of the product, inhibit adverse water migration and starch aging, thereby delaying moisture regain and water loss hardening, maintaining the sensory acceptable period, prolonging the shelf life and improving the storage and transportation tolerance.

[0006] To achieve the above-mentioned purposes, the technical solutions adopted by the present application are as follows: In a first aspect, the present application provides a preparation method of a Chinese tea cake of Wuniuzao tea, comprising the following steps: S100, finely processing Wuniuzao tea raw materials to obtain Wuniuzao tea powder; S200, mixing the Wuniuzao tea powder, low-gluten flour and pre-gelatinized starch to obtain a dry mixture; S300, face-making treatment of the dry mixture with an enzyme solution to form a dough; S400, packaging the filling into the dough skin to form a green body; S500, segmented baking of the green body to obtain the Chinese tea cake of Wuniuzao tea.

[0007] In an optional embodiment, step S300 specifically includes: S310, mixing the dry mixture with the first enzyme solution at 25-30°C for 10-18 min to obtain a first intermediate product; S320, adding a second enzyme solution to the first intermediate product and kneading at 25-30°C for 15-25 min to obtain a second intermediate product; S330, heating the second intermediate product to obtain dough; wherein the first enzyme solution includes α-amylase; and the second enzyme solution includes transglutaminase and glucose oxidase.

[0008] In an alternative implementation, a frequency of 20-40 kHz and a power density of 0.5-2 W / cm² are applied simultaneously with the dough kneading process. 2 The ultrasonic treatment lasts for 30-120 seconds.

[0009] In an optional implementation, in step S320, the amount of transglutaminase added is 0.05-0.5 U / g flour, and the amount of glucose oxidase added is 0.01-0.1 U / g flour.

[0010] In an optional implementation, in step S330, the heat treatment temperature is 40-45°C and the time is 5-15 min.

[0011] In an optional implementation, in step S100, the D50 of the Wuniuzao tea powder is 10-25µm and the moisture content is 1-5wt%.

[0012] In an optional implementation, in step S200, the mass ratio of Wuniu Zaocha powder, low-gluten flour and pregelatinized starch is (3-6):100:(8-12).

[0013] In an optional implementation, in step S400, the filling is prepared by the following steps: S401, the filling raw materials are dehydrated and 5-20 wt% of auxiliary materials are added to obtain the filling; wherein, the auxiliary materials include maltodextrin or inulin; the moisture content of the filling is 20-35 wt%.

[0014] In an optional implementation, in step S500, the segmented baking includes a pre-baking process and a main baking process; the temperature of the pre-baking process is 170-190℃ and the time is 5-12 min; the temperature of the main baking process is 140-170℃ and the time is 15-35 min.

[0015] Secondly, embodiments of this application provide a Chinese-style tea pastry for Wuniu Zaocha, which is prepared by any of the above-mentioned preparation methods.

[0016] The beneficial effects of this application include at least the following: (1) By synergistic addition of Wuniuzao tea powder and pregelatinized starch, stepwise enzymatic construction of a strong gluten network and segmented baking, the Chinese tea pastry prepared by this application can effectively inhibit moisture migration and starch retrogradation during storage. The product has a reduced hardness increase rate, high elasticity retention rate, stable water activity and slow sensory quality deterioration after accelerated storage, thereby delaying moisture and hardening, significantly extending the shelf life of the product and improving storage and transportation tolerance. (2) The pregelatinized starch and tea powder in this application enhance the water binding capacity of the system; the stepwise action of α-amylase, transglutaminase and glucose oxidase results in a dough network structure with both good plasticity and long-lasting anti-aging properties; segmented baking optimizes the moisture state of the surface and interior. Detailed Implementation

[0017] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are only for explaining this application, but the implementation of this application is not limited thereto.

[0018] Unless otherwise defined, the technical terms used in the following embodiments have the same meanings as commonly understood by those skilled in the art to which this application pertains. Unless otherwise specified, the experimental reagents used in the following embodiments are conventional biochemical reagents; the amounts of experimental reagents used are, unless otherwise specified, the amounts used in conventional experimental operations; and the experimental methods used are, unless otherwise specified, conventional methods.

[0019] Chinese tea pastries, as a distinctive food combining traditional pastries and tea culture, not only carry regional flavors but also meet the fast-moving consumer goods market's demand for portable, ready-to-eat, and Chinese-style retail products. As consumers increasingly demand flavor stability, consistent texture, and room-temperature shelf life, the pastry industry is developing towards functionalized formulas and controllable processes. However, existing Chinese tea pastries generally suffer from short shelf life and poor storage stability. During room-temperature storage, moisture migration and starch retrogradation lead to densification and a hardened texture, issues that traditional formulas and single-stage high-temperature baking cannot effectively mitigate.

[0020] In view of the above-mentioned shortcomings in the existing technology, the purpose of this application is to provide a Chinese tea pastry of Wuniu Zaocha and its preparation method, which aims to solve the problems of traditional tea pastries being prone to moisture reabsorption, hardening and short shelf life during storage due to moisture migration and starch retrogradation.

[0021] In a first aspect, embodiments of this application provide a method for preparing Chinese-style tea pastries for Wuniu Zaocha (a type of tea), comprising the following steps: S100. The raw materials of Wuniu Zaocha are refined to obtain Wuniu Zaocha powder; S200. Mix Wuniu Zaocha powder, low-gluten flour and pregelatinized starch to obtain a dry mixture; S300: Knead the dry mixture with the enzyme solution to form a dough; S400: Wrap the filling in the dough to form a raw dough; S500: The raw dough is baked in sections to obtain Wuniu Zaocha Chinese-style tea pastries.

[0022] Preferably, this embodiment employs a mixture of Wuniuzao tea powder, low-gluten flour, and pregelatinized starch, along with enzymatic modification, dough kneading, and segmented baking techniques to improve the moisture binding state and microstructure of the dough system, thereby effectively inhibiting unfavorable moisture migration and starch retrogradation during storage. Specifically, adding Wuniuzao tea powder and pregelatinized starch not only increases the hydrophilic components but also competes with starch and protein for water binding, reducing free water content; enzymatic kneading strengthens the gluten protein network, forming a dense and elastic microstructure, thereby binding moisture and physically restricting the rearrangement of starch molecular chains; the segmented baking process controls the rate of water vapor escape and the surface densification process through temperature gradients, which is conducive to forming a suitable moisture gradient and surface structure, reducing excessive water loss during baking. The synergistic effect of the above technologies effectively delays the stickiness or hardening of the pastry due to moisture absorption and rehydration, thus maintaining a longer sensory acceptable period and improving the product's storage and transportation tolerance.

[0023] Furthermore, in step S100, grinding the Wuniuzao tea powder to a D50 of 10-25µm facilitates the uniform dispersion of tea powder in the formula, avoiding localized agglomeration of tea powder leading to differences in localized moisture content or surface defects. This ensures the uniform distribution of flavor substances in the dough matrix, preventing uneven dispersion, rough texture, and uneven color caused by excessively coarse particles. It also prevents excessive agglomeration and moisture absorption due to excessively fine particles, which would affect the stability of the process. Controlling the powder moisture content to 1-5wt% maximizes the retention of active tea components, ensures powder flowability and storage stability, effectively inhibits microbial growth and deterioration of the tea's quality, reduces free and mobile water in the powder, slows down water migration, and avoids introducing excessive free water during kneading, which could lead to locally overly wet dough and uneven structure.

[0024] Preferably, in step S200, the mass ratio of Wuniuzao tea powder, low-gluten flour, and pregelatinized starch is (3-6):100:(8-12). This ratio range ensures sufficient tea flavor while maintaining the continuity of the dough network. The pregelatinized starch, at 8-12 parts, forms a continuous water-absorbing and water-retaining colloidal layer without excessively replacing flour, which could lead to difficulty in dough shaping or a powdery texture. Within this range, the finished product exhibits a higher bound water content, a lower free water ratio, and a more uniform microporous structure. The hydrogel phase formed by the pregelatinized starch partially encapsulates volatile components after baking, slowing their escape while maintaining the slow release of moisture from the surface and interior. Low-gluten flour primarily provides the necessary protein-starch network substrate, while tea powder, as a functional filler and flavor source, occupies the network gaps. Too much tea powder will damage the network strength and increase cracks, while too little tea powder will result in insufficient flavor. Pregelatinized starch, due to its gelatinized properties, can form a network colloid at low temperatures, enhancing water binding and reducing capillary water migration rate by forming a viscoelastic phase interface, thereby delaying moisture regain and hardening.

[0025] Specifically, step S300 includes: S310. Mix the dry mixture with the first enzyme solution at 25-30℃ for 10-18 min to obtain the first intermediate product; S320. Add the second enzyme solution to the first intermediate product and knead the dough at 25-30℃ for 15-25 minutes to obtain the second intermediate product. S330. The second intermediate product is heated to obtain dough; The first enzyme solution includes α-amylase; the second enzyme solution includes transglutaminase and glucose oxidase.

[0026] Preferably, in step S300, a stepwise enzymatic dough-making process is adopted, first adding α-amylase, then transglutaminase (TG enzyme) and glucose oxidase (GOx enzyme). By controlling the action sequence of different enzymes and the substrate environment, the synergistic optimization of the dough's microstructure can be achieved. If the three enzymes are added all at once, the premature and excessive hydrolysis of starch chains by α-amylase will weaken the dough's skeletal structure, potentially leading to an overly soft, sticky, or collapsed dough. The α-amylase added first hydrolyzes starch to a limited extent under mild conditions, producing a small amount of short-chain dextrins and soluble sugars, which can reduce the initial viscosity of the dough, improve its extensibility and facilitate dough making and filling, and provide substrates for subsequent flavor-forming reactions. Subsequently, TG enzyme and GOx enzyme were added. Working synergistically, TG enzyme directly catalyzes the formation of covalent ε-(γ-glutamyl)-lysine cross-links between gluten protein molecules, significantly enhancing the network's elasticity and strength. GOx enzyme, through oxidation, promotes the formation of a denser disulfide bond network in flour, further improving the dough's toughness and structural stability. Therefore, the synergistic effect of these three enzymes—α-amylase improving the uniformity of free water and viscosity and generating short-chain dextrins to improve water binding; TG enzyme catalyzing the cross-linking of ε-(γ-glutamyl)-lysine between proteins, enhancing network elasticity and reducing segregation and dripping; and GOx enzyme altering the balance of thiols and disulfide bonds in the dough through redox reactions and generating trace amounts of H2O2 to promote oxidative cross-linking, indirectly improving network strength and stability—gives the dough suitable plasticity and strength during processing, resulting in a more water-holding and anti-aging microstructure in the final product, laying a crucial foundation for extending the shelf life of pastries.

[0027] Furthermore, in step S310, the α-amylase is mixed and treated at 25-30°C for 10-18 minutes. This temperature range is the optimal temperature range for α-amylase, which can achieve gentle starch chain cleavage, improve the plasticity and water absorption of the dough without excessively degrading the starch into low-molecular-weight sugars, and avoid the side effects of sweetness and excessive viscosity. 10-18 minutes ensures sufficient reaction time to produce an appropriate amount of dextrin and oligosaccharides, but is shorter than the time window that can lead to excessive hydrolysis.

[0028] Furthermore, in step S310, active hydrogen water, tea oil, and rock sugar powder can be added. When active hydrogen water is used as a solvent for kneading dough, it has antioxidant properties and can reduce the level of free radicals related to oxidative stress under certain conditions. It can protect easily oxidized flavor substances and reduce flavor loss or color changes caused by oxidation. As a natural plant oil, tea oil is rich in oleic acid and natural antioxidants. Adding it can improve the lubricity and texture of the dough and provide certain antioxidant protection to delay lipid oxidation and flavor deterioration. In addition, the lipid phase formed by the oil phase in the dough can reduce direct evaporation of water and improve the softness after baking. Rock sugar powder has a moisturizing effect in pastries in addition to sweetness. It can reduce the dryness after baking and delay hardening. After being finely powdered, rock sugar powder can be used as an energy and sweetness source and also helps to maintain the softness of the filling and the dough.

[0029] Further, in step S320, the TG enzyme and GOx enzyme are kneaded at 25-30℃ for 15-25 minutes. This temperature range balances activity and protein conformation stability. 15-25 minutes provides sufficient time for the cross-linking reaction while avoiding over-cross-linking that could lead to decreased toughness or a hardened texture. The TG enzyme is added at 0.05-0.5 U / g flour, and the GOx enzyme at 0.01-0.1 U / g. The amount of TG enzyme added is used to adjust the cross-linking density for different formulation strength requirements; low doses provide mild reinforcement to maintain softness, while high doses can be used for formulations requiring stronger structural support. The GOx enzyme is used to achieve mild oxidation, promoting disulfide bond cross-linking with other oxidative bonds without causing over-oxidation.

[0030] Furthermore, during the dough kneading process, a frequency of 20-40kHz and a power density of 0.5-2W / cm² are applied. 2 Ultrasonic treatment for 30-120 seconds enhances solid-liquid mass transfer through cavitation and micro-shear effects, improving rapid wetting and uniform dispersion of powders. It also facilitates interfacial bonding between tea powder, pregelatinized starch, and flour, shortening the enzyme-substrate contact time, thereby increasing enzymatic efficiency and reducing enzyme dosage or reaction time. Simultaneously, ultrasound can induce partial rupture or surface gelatinization of starch granules, increasing their usable surface area and water absorption rate, promoting the formation of a tighter water-bound phase, ultimately improving post-drying water retention and structural uniformity. Ultrasonic cavitation generates localized high shear stress and microturbulence in a short time, promoting rapid mixing of the dispersed phase and solvent, and making it easier for the enzyme to contact and act on the substrate. An applied frequency of 20-40 kHz can generate effective cavitation without directly damaging the macromolecular network; the power density is 0.5-2 W / cm². 2 For a practical and controllable intensity range, a time of 30-120 seconds can improve dispersion and mass transfer, but avoid prolonged cavitation that could lead to protein breakage or excessive shear damage to the dough network; excessively high frequency, power, or duration can cause local dehydration of the dough, protein breakage, or abnormal viscosity.

[0031] Furthermore, in step S330, the heating treatment temperature is 40-45℃ and the time is 5-15min. The heating treatment is used on the one hand to partially deactivate or weaken enzyme activity to lock in the existing modification results and avoid over-reaction in subsequent processing. On the other hand, under gentle heating, it can promote the rearrangement and partial gelation of protein and starch molecules, improve the processability and morphological stability of the dough. At this temperature, physical cross-linking and water binding can be accelerated without causing irreversible denaturation of proteins or excessive water evaporation. The 5-15min time is to ensure the intended effect of enzyme action while avoiding excessive heating that could cause water loss and enzyme degradation side effects.

[0032] Preferably, in step S400, the filling is prepared through the following steps: S401, the filling raw materials are dehydrated, and auxiliary materials accounting for 5-20 wt% of the weight of the filling raw materials are added to obtain the filling; wherein, the auxiliary materials include maltodextrin or inulin; the moisture content of the filling is 20-35 wt%; the dehydration of the filling is to control the free water content of the filling within a range that ensures extrudability and formability without causing local dampness or delamination of the dough after wrapping; the auxiliary materials are added at 5-20 wt% of the weight of the filling raw materials, and the polysaccharide excipients are used to improve the viscoelasticity of the filling, enhance its water binding capacity, and reduce its free water activity, thereby reducing the rehydration or softening caused by water migration between the filling and the dough. Maltodextrin, as a low-molecular-weight starch degradation product, possesses excellent rheological regulation and water retention properties, and can form a colloidal phase. Inulin, a soluble dietary fiber, can form a viscous sol, improving adhesion and binding water. Through these additives, the proportion of free water in the filling decreases after baking and during storage, thereby reducing the water migration load on the dough and synergistically extending the overall shelf life of the product. Controlling the moisture content of the filling at 20-35 wt% ensures both taste and processability, avoiding both excessive moisture leading to collapse or steaming and subsequent filling collapse, and excessive dryness resulting in a rough texture or surface cracks after baking.

[0033] Preferably, segmented baking controls the different heat-mass transfer requirements of the surface and interior by setting a short, high-temperature pre-baking period and a relatively long, medium-low-temperature main baking period. Pre-baking helps form a dense outer layer to reduce rapid steam escape and oil seepage, and reduces direct water vapor exchange between the filling and the dough; the main baking is carried out at a lower temperature, which can complete the internal maturation without causing a large amount of volatile substances to be lost at once or causing excessive internal dehydration. The surface vitrification and protein coagulation layer produced by pre-baking acts as a barrier layer for water vapor diffusion, reducing the instantaneous steam flow rate; subsequently, the main baking allows residual internal moisture to migrate slowly and reach a new thermodynamic equilibrium under mild conditions through evaporation and redistribution, thereby reducing the moisture gradient between the surface and interior after baking, ultimately reducing the rate of rehydration, cracking, and hardening due to dehydration, and extending storage stability.

[0034] Furthermore, to improve the overall stability of the product during storage, transportation, and shelf life, a surface treatment step may be included after the segmented baking in step S500: coating the surface of the Wu Niu Zao Cha Chinese tea pastry with an edible film solution containing pullulan, which, after drying, forms a dry film with a weight of 0.2-1.0 g / m³. 2 The protective layer.

[0035] Specifically, the protective layer, acting as a physical barrier, effectively isolates the surface of the pastry from direct contact with the external environment, slowing down the exchange rate of moisture and volatile flavor compounds, thereby delaying hardening caused by moisture absorption or dehydration. The dense polysaccharide network increases the tortuosity of gas diffusion paths, reducing the migration rate of oxygen into the product's interior and helping to delay oxidative rancidity. Simultaneously, the protective layer itself can serve as a carrier for functional substances, such as loading antioxidants or antibacterial agents, thus layering chemical protection on top of physical barriers to further inhibit quality deterioration. Pullulan can bind well to hydroxyl and protein groups in the pastry surface through intermolecular hydrogen bonds, forming a firmly attached continuous phase. During the drying process, the solution concentrates and fills the microscopic cracks and pores on the surface of the pastry, forming a dense network. This structure increases the tortuosity and energy barrier required for the penetration of water molecules, oxygen, and aroma substances. For water, the film partially binds the surface free water through adsorption, smoothing the water activity gradient between the surface and the external environment. For aroma, it provides certain adsorption sites, slowing down its escape. For microorganisms, it constitutes a direct physical barrier layer.

[0036] In addition, the dry film weight is 0.2-1.0 g / m³. 2 Based on the balance between effectiveness and taste, this dosage is sufficient to form a complete and effective sealing layer, inhibiting mass migration primarily through the surface, while having no negative impact on the product's sensory characteristics.

[0037] Secondly, this application also provides a Chinese-style tea pastry for Wuniu Zaocha, prepared by any of the above preparation methods.

[0038] This application has undergone multiple experiments, and some of the test results are presented here for reference to further describe the invention in detail. The following is a detailed description in conjunction with specific embodiments.

[0039] Example 1 This embodiment provides a Chinese-style tea pastry for Wuniu Zaocha (a type of tea), and its preparation method, including the following steps: S100. The Wuniuzao tea leaves are pulverized using an ultra-fine pulverizer, sieved and graded, and then dried by forced air to control the moisture content to 3wt%, resulting in Wuniuzao tea powder with a particle size D50 of 15µm. S200: Mix 5g of Wuniu Zaocha powder, 100g of low-gluten flour and 10g of pregelatinized starch to obtain a dry mixture; S310. Transfer the dry mixture to a dough mixer, add the first enzyme solution containing α-amylase at an addition amount of 0.1 U / g flour, mix and stir at 28°C for 15 min to obtain the first intermediate product; S320: A second enzyme solution containing 0.2 U / g transglutaminase from flour and 0.05 U / g glucose oxidase from flour was added to the first intermediate product. The mixture was kneaded at 28°C for 20 minutes, while simultaneously subjected to ultrasonic treatment at a frequency of 28 kHz and a power density of 1.0 W / cm³. 2 After acting for 60 seconds, the second intermediate product is obtained. S330. The second intermediate product is heated in a constant temperature oven at 42°C for 10 minutes to obtain dough. S401. Vacuum dehydration of pumpkin puree is performed, and maltodextrin accounting for 10 wt% of the weight of the filling ingredients is added to obtain the filling. The final moisture content of the filling is adjusted to 30 wt%. S400: Wrap the filling in the dough to form a raw dough; S500: The raw dough is baked in sections, pre-baked at 180℃ for 8 minutes, and then baked at 150℃ for 25 minutes. After cooling, the Chinese tea pastry of Wuniu Zaocha is obtained.

[0040] Example 2 This embodiment provides a Chinese-style tea pastry for Wuniu Zaocha (a type of tea), and its preparation method, including the following steps: S100. The Wuniuzao tea leaves are pulverized using an ultra-fine pulverizer, sieved and graded, and then dried by forced air to control the moisture content to 4.5wt%, resulting in Wuniuzao tea powder with a particle size D50 of 22µm. S200: Mix 3g of Wuniu Zaocha powder, 100g of low-gluten flour and 8g of pregelatinized starch to obtain a dry mixture; S310. Transfer the dry mixture to a dough mixer, add the first enzyme solution containing α-amylase at an addition amount of 0.1 U / g flour, mix and stir at 25°C for 18 min to obtain the first intermediate product; S320: A second enzyme solution containing 0.05 U / g transglutaminase from flour and 0.01 U / g glucose oxidase from flour is added to the first intermediate product. The mixture is then kneaded at 25°C for 25 minutes, while simultaneously subjected to ultrasonic treatment at a frequency of 20 kHz and a power density of 0.5 W / cm³. 2 After acting for 120 seconds, the second intermediate product was obtained. S330. The second intermediate product is heated in a constant temperature oven at 40°C for 15 minutes to obtain dough. S401. Vacuum dehydrate the red bean paste and add inulin at 8 wt% of the weight of the filling ingredients to obtain the filling. Adjust the final moisture content of the filling to 22 wt%. S400: Wrap the filling in the dough to form a raw dough; S500: The raw dough is baked in sections, pre-baked at 190℃ for 5 minutes, and then baked at 170℃ for 18 minutes. After cooling, the Chinese-style tea pastry of Wuniu Zaocha is obtained.

[0041] Example 3 This embodiment provides a Chinese-style tea pastry for Wuniu Zaocha (a type of tea), and its preparation method, including the following steps: S100. The Wuniuzao tea leaves are pulverized using an ultra-fine pulverizer, sieved and graded, and then dried by forced air to control the moisture content to 1.5wt%, resulting in Wuniuzao tea powder with a particle size D50 of 10µm. S200: Mix 6g of Wuniu Zaocha powder, 100g of low-gluten flour and 12g of pregelatinized starch to obtain a dry mixture; S310. Transfer the dry mixture to a dough mixer, add the first enzyme solution containing α-amylase at an addition amount of 0.1 U / g of flour. The first enzyme solution is prepared with active hydrogen water, and additionally add 3% tea oil and 5% rock sugar powder by weight of flour. Mix and stir at 30°C for 10 minutes to obtain the first intermediate product. S320: A second enzyme solution containing 0.5 U / g transglutaminase and 0.1 U / g glucose oxidase from flour was added to the first intermediate product. The mixture was kneaded at 30°C for 15 minutes, while simultaneously subjected to ultrasonic treatment at a frequency of 40 kHz and a power density of 2.0 W / cm³. 2 After acting for 30 seconds, the second intermediate product is obtained. S330. The second intermediate product is heated in a constant temperature oven at 45°C for 5 minutes to obtain dough. S401. Vacuum dehydration of jujube paste is performed, and maltodextrin accounting for 18 wt% of the weight of the filling ingredients is added to obtain the filling. The final moisture content of the filling is adjusted to 32 wt%. S400: Wrap the filling in the dough to form a raw dough; S500: The raw dough is baked in sections, pre-baked at 170℃ for 10 minutes, and then baked at 140℃ for 32 minutes. After cooling, the Chinese tea pastry of Wuniu Zaocha is obtained.

[0042] Example 4 This embodiment provides a Chinese-style tea pastry for Wuniu Zaocha (a type of tea), and its preparation method. The preparation method of this Chinese-style tea pastry for Wuniu Zaocha is the same as that shown in Embodiment 1, except that: in step S500, the pastry is further coated with a 0.5% pullulan polysaccharide aqueous solution after cooling, drained, and then dried at 40°C to form a dry film with a weight of 0.5 g / m³. 2 The protective layer is used to make Wu Niu Zao Cha, a Chinese tea pastry.

[0043] Example 5 This embodiment provides a Chinese-style tea pastry for Wuniu Zaocha (a type of tea), and its preparation method. The preparation method of this Chinese-style tea pastry for Wuniu Zaocha is the same as that shown in Embodiment 1, except that: in step S500, the method further includes spraying the cooled pastry with a 1.0% pullulan polysaccharide solution containing 0.1% tea polyphenols, draining it, and then drying it at 40°C to form a dry film with a weight of 1.0 g / m³. 2 The protective layer is used to make Wu Niu Zao Cha, a Chinese tea pastry.

[0044] Example 6 This embodiment provides a Chinese-style tea pastry for Wuniu Zaocha and its preparation method. The preparation method of the Chinese-style tea pastry for Wuniu Zaocha is the same as that shown in Embodiment 1, except that ultrasonic treatment is not applied during the dough kneading process.

[0045] Comparative Example 1 This comparative example provides a Chinese-style tea pastry based on Wuniu Zaocha tea and its preparation method. The preparation method of this Chinese-style tea pastry based on Wuniu Zaocha tea is the same as that shown in Example 1, except that in step S200, the dry mixture consists of only 5g of Wuniu Zaocha tea powder and 110g of low-gluten flour, that is, no pregelatinized starch is added.

[0046] Comparative Example 2 This comparative example provides a Chinese-style tea pastry for Wuniu Zaocha and its preparation method. The preparation method of the Chinese-style tea pastry for Wuniu Zaocha is the same as that shown in Example 1, except that steps SS310 and S320 are omitted, i.e., α-amylase, transglutaminase and glucose oxidase are added to the dry mixture at the same time and kneaded at 28°C for 35 minutes.

[0047] Comparative Example 3 This comparative example provides a Chinese-style tea pastry for Wuniu Zaocha and its preparation method. The preparation method of the Chinese-style tea pastry for Wuniu Zaocha is the same as that shown in Example 1, except that in step S500, there is no segmented baking, that is, a one-time baking is used, and the baking is carried out continuously at a temperature of 165°C for 33 minutes.

[0048] Comparative Example 4 This comparative example provides a Chinese-style tea pastry for Wuniu Zaocha and its preparation method. The preparation method of the Chinese-style tea pastry for Wuniu Zaocha is the same as that shown in Example 1, except that: in step S401, maltodextrin is not added when preparing the filling, and only dehydration treatment is performed.

[0049] Test method: Accelerated storage tests were conducted on the Chinese-style tea pastries made from Wuniu Zaocha prepared in Examples 1-6 and Comparative Examples 1-4. The pastries were stored at 37°C and 75% relative humidity for 14 days to accelerate the evaluation of the storage stability of the products. The initial and post-storage hardness, elasticity, water activity and sensory scores were also tested. The results are shown in Table 1. Table 1 As shown in Table 1, Examples 1-6, employing the technologies of pregelatinized starch, stepwise enzymatic polymerization, segmented baking, and filling moisture control proposed in this application, exhibited a relatively gradual increase in hardness and high elasticity retention after storage. In contrast, the comparative examples, lacking key technologies, showed a surge in hardness and a significant decrease in elasticity, indicating severe hardening and reduced toughness. Examples 1-6, by optimizing the water binding and migration barriers, achieved stable or slightly decreased water activity after storage, indicating a stable internal water state and effective suppression of free water migration. The comparative examples 1 (without pregelatinized starch), 3 (single-segment baking), and 4 (high-moisture filling without additives) showed higher or increasing aw values, revealing that their internal water was more active and prone to migration, a significant cause of quality deterioration. Examples 1-6 maintained sensory scores above 8.1 after storage, indicating good flavor, texture, and overall acceptability.

[0050] In summary, the embodiments of this application, after accelerated storage, are significantly superior to comparative products lacking any key technology in terms of texture retention, moisture stability, and sensory quality, demonstrating that the preparation method of this application can effectively delay rehydration and hardening, extend shelf life, and improve storage and transportation tolerance.

[0051] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for preparing Chinese-style tea pastries for Wuniu Zaocha (a type of tea), characterized in that, Includes the following steps: S100. The raw materials of Wuniu Zaocha are refined to obtain Wuniu Zaocha powder; S200. The Wuniu Zaocha powder, low-gluten flour and pregelatinized starch are mixed to obtain a dry mixture; S300: The dry mixture is kneaded with the enzyme solution to form a dough; S400: Wrap the filling in the dough made from the dough and shape it to obtain a raw dough; S500: The raw dough is baked in sections to obtain the Chinese-style tea pastry of Wuniu Zaocha.

2. The preparation method according to claim 1, characterized in that, Step S300 specifically includes: S310. The dry mixture is mixed with the first enzyme solution at 25-30°C for 10-18 min to obtain the first intermediate product; S320. Add the second enzyme solution to the first intermediate product, and perform the dough kneading treatment at 25-30℃ for 15-25 minutes to obtain the second intermediate product. S330. The second intermediate product is heated to obtain the dough; The first enzyme solution includes α-amylase; The second enzyme solution includes transglutaminase and glucose oxidase.

3. The preparation method according to claim 1 or 2, characterized in that, During the kneading process, a frequency of 20-40 kHz and a power density of 0.5-2 W / cm² are applied. 2 The ultrasonic treatment lasts for 30-120 seconds.

4. The preparation method according to claim 2, characterized in that, In step S320, the amount of transglutaminase added is 0.05-0.5 U / g flour, and the amount of glucose oxidase added is 0.01-0.1 U / g flour.

5. The preparation method according to claim 2, characterized in that, In step S330, the heating treatment temperature is 40-45℃ and the time is 5-15 minutes.

6. The preparation method according to claim 1, characterized in that, In step S100, the D50 of the Wuniuzao tea powder is 10-25µm and the moisture content is 1-5wt%.

7. The preparation method according to claim 1, characterized in that, In step S200, the mass ratio of the Wuniu Zaocha powder, the low-gluten flour and the pregelatinized starch is (3-6):100:(8-12).

8. The preparation method according to claim 1, characterized in that, In step S400, the filling is prepared by the following steps: S401. Dehydrate the filling ingredients and add auxiliary materials accounting for 5-20 wt% of the weight of the filling ingredients to obtain the filling. The excipients include maltodextrin or inulin; The moisture content of the filling is 20-35 wt%.

9. The preparation method according to claim 1, characterized in that, In step S500, the segmented baking includes a pre-baking process and a main baking process; The pre-drying process is carried out at a temperature of 170-190℃ for 5-12 minutes. The main drying process is carried out at a temperature of 140-170℃ for 15-35 minutes.

10. A type of Chinese tea pastry for Wuniu Morning Tea, characterized in that, It is prepared by the preparation method described in any one of claims 1-9.

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