Instant tartary buckwheat tea powder and preparation method thereof

Abstract

The present application relates to the technical field of food processing, and particularly relates to a kind of instant tartary buckwheat tea powder and a preparation method thereof, the present application is effectively protected in the heat-sensitive active substance in tartary buckwheat, Chinese olive leaf and mulberry leaf by carbon dioxide inert atmosphere low-temperature roasting, vacuum freeze drying and low-frequency pulse electric field processing;Key ingredients of radix astragali and eucommia male flower are stabilized by using β-cyclodextrin embedding technology, reducing processing loss;Flavor substances are extracted by combining subcritical water extraction process, and the synergistic release and fusion of various functional ingredients are promoted by means of simultaneous fermentation and enzymatic reaction;Finally, through low-temperature spray drying process, the solubility, stability and comprehensive quality of the product are significantly improved while the active ingredients and flavors are retained to the greatest extent, solving the technical problems of easy destruction of active ingredients, volatile substance escape and difficulty in effective integration of various raw materials in traditional process.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, and in particular to an instant buckwheat tea powder and its preparation method. Background Technology

[0002] Buckwheat tea is a traditional health beverage made primarily from buckwheat. It is rich in flavonoids, dietary fiber, and various trace elements, and possesses physiological functions such as anti-oxidation and regulation of blood sugar and lipids. In recent years, with the increasing demand for convenient and healthy foods, instant buckwheat tea powder has gradually gained market favor. Currently, the preparation of instant buckwheat tea powder mainly focuses on the single or simple compound processing of buckwheat, with common processes including roasting, grinding, extraction, concentration, and drying.

[0003] However, existing preparation methods are difficult to effectively integrate the active ingredients of multiple functional raw materials, and lack protection for heat-sensitive and volatile components during processing, resulting in lower overall quality of the final product. Summary of the Invention

[0004] The purpose of this invention is to provide an instant buckwheat tea powder and its preparation method, which solves the technical problems in the prior art of effectively integrating the active ingredients of multiple functional raw materials and lacking protection for heat-sensitive and volatile components during processing, resulting in a low overall quality of the final product.

[0005] To achieve the above objectives, the present invention provides a method for preparing instant buckwheat tea powder, comprising: Buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves were pretreated separately. After being washed, the buckwheat grains were roasted at low temperature under an inert carbon dioxide atmosphere. Eucommia ulmoides leaves and mulberry leaves were freeze-dried under vacuum and then treated with a low-frequency pulse electric field. After pulverizing the Astragalus membranaceus slices, they were mixed with Eucommia ulmoides male flowers at a weight ratio of 1-3:1, and then encapsulated with β-cyclodextrin aqueous solution. After vacuum low-temperature drying, the encapsulated mixture was obtained. Honeysuckle, dandelion and mint leaves were mixed in a weight ratio of 2:2:1, and flavor functional extracts were obtained by subcritical water extraction technology, which were then concentrated for later use. Pretreated buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves are mixed in a weight ratio of 75-85: 10-15: 5-10, pulverized, and then mixed with water to make a slurry. Simultaneous addition of an encapsulation mixture, flavor functional extracts, compound microbial agents, and compound enzyme preparations to the slurry, followed by simultaneous fermentation and enzymatic hydrolysis in an integrated reactor; After the reaction is complete, the mixture is inactivated, centrifuged, and the supernatant is filtered through a membrane. The filtrate is then concentrated under vacuum and spray-dried at low temperature to obtain the instant buckwheat tea powder.

[0006] The low-temperature roasting conditions for buckwheat grains are as follows: under a carbon dioxide atmosphere, the temperature is increased from room temperature to 95-110℃ at a rate of 3-5℃ / minute and held for 15-25 minutes. The low-frequency pulsed electric field treatment parameters for Cyclocarya paliurus leaves and mulberry leaves were: field strength 15-30 kV / cm, pulse frequency 50-200 Hz, and treatment time 5-15 minutes.

[0007] In the step of "simultaneously adding compound bacterial agent and compound enzyme preparation to the slurry and carrying out synchronous fermentation and enzymatic hydrolysis reaction in an integrated reactor", the concentration changes of two target components, γ-aminobutyric acid and tartary buckwheat peptide with a molecular weight of less than 1000 Daltons, in the reaction system are monitored in real time by an online near-infrared spectrometer. The monitoring data is input into the process control algorithm in real time. The algorithm dynamically adjusts the temperature, stirring rate and pH value of the reactor based on the real-time concentration and change rate of the two target components, so that the reaction process always moves in the direction of maximizing the synthesis of γ-aminobutyric acid and tartary buckwheat peptide. The compound microbial agent is a co-culture of Lactobacillus plantarum and Streptococcus thermophilus, with a live bacteria ratio of 1:1-2; the compound enzyme preparation contains cellulase, pectinase and neutral protease.

[0008] The process control algorithm is based on the principle of fuzzy PID control. Its core control rules include: when the rate of increase of γ-aminobutyric acid concentration is lower than the preset threshold A, the algorithm outputs a command to increase the reaction temperature by 0.5-1.5℃ within the set range; when the concentration of small molecule buckwheat peptide reaches the plateau period, the algorithm outputs a command to adjust the pH value downward by 0.2-0.4 units to promote protease activity.

[0009] The membrane filtration uses an ultrafiltration membrane with a molecular weight cutoff of 5000 Daltons; the inlet air temperature of the low-temperature spray drying is 85-95℃, and the outlet air temperature is 45-55℃.

[0010] The endpoint of the simultaneous fermentation and enzymatic hydrolysis reaction is determined by the dynamic optimization model according to the following rules: when the concentration of γ-aminobutyric acid increases below 0.05 mg / g / h for three consecutive monitoring periods, and the proportion of small molecule buckwheat peptides reaches a plateau of 65%-75% of the total peptide content, the model issues a termination command.

[0011] This invention also provides an instant buckwheat tea powder, prepared using the method described above. The instant buckwheat tea powder contains γ-aminobutyric acid (GABA) at a content of not less than 2.0 mg / g, and buckwheat peptides with a molecular weight of less than 1000 Daltons account for not less than 60% of the total peptide content.

[0012] This invention discloses an instant buckwheat tea powder and its preparation method. The invention effectively protects the heat-sensitive active substances in buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves through low-temperature roasting in an inert carbon dioxide atmosphere, vacuum freeze-drying, and low-frequency pulsed electric field treatment. It utilizes β-cyclodextrin encapsulation technology to stabilize key components of Astragalus membranaceus and Eucommia ulmoides male flowers, reducing processing losses. Flavor substances are extracted using subcritical water extraction, and simultaneous fermentation and enzymatic hydrolysis promote the synergistic release and fusion of multiple functional components. Finally, through low-temperature spray drying and other processes, the product's solubility, stability, and overall quality are significantly improved while maximizing the preservation of active ingredients and flavor. This solves the technical problems of easy destruction of active ingredients, loss of volatile substances, and difficulty in effectively integrating multiple raw materials in traditional processes. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0014] Figure 1 This is a flowchart of the preparation method of the instant buckwheat tea powder of the present invention. Detailed Implementation

[0015] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0016] Please see Figure 1 , Figure 1 This is a flowchart of the preparation method of the instant buckwheat tea powder of the present invention.

[0017] This invention provides a method for preparing instant buckwheat tea powder, comprising: S1. Tartary buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves are pretreated separately. After being washed, the tartary buckwheat grains are roasted at low temperature under an inert carbon dioxide atmosphere. Eucommia ulmoides leaves and mulberry leaves are freeze-dried under vacuum and then treated with a low-frequency pulse electric field. For this specific embodiment, the low-temperature roasting conditions for buckwheat grains are as follows: under a carbon dioxide atmosphere, the temperature is increased from room temperature to 95-110°C at a rate of 3-5°C / minute and held for 15-25 minutes. The low-frequency pulsed electric field treatment parameters for Cyclocarya paliurus leaves and mulberry leaves were: field strength 15-30 kV / cm, pulse frequency 50-200 Hz, and treatment time 5-15 minutes.

[0018] S2. After pulverizing the Astragalus membranaceus slices, mix them with Eucommia ulmoides male flowers at a weight ratio of 1-3:1, embed them with β-cyclodextrin aqueous solution, and then vacuum low temperature drying to obtain the embedded mixture. S3. Mix honeysuckle, dandelion and mint leaves in a weight ratio of 2:2:1, and use subcritical water extraction technology to obtain flavor functional extracts, which are then concentrated for later use. S4. Mix the pretreated buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves in a weight ratio of 75-85: 10-15: 5-10, crush them, and then mix them with water to make a slurry. S5. Simultaneously add the encapsulation mixture, flavor functional extract, compound microbial agent and compound enzyme preparation to the slurry, and carry out simultaneous fermentation and enzymatic hydrolysis in an integrated reactor. In this specific embodiment, in the step of "simultaneously adding compound bacterial agent and compound enzyme preparation to the slurry and carrying out simultaneous fermentation and enzymatic hydrolysis reaction in an integrated reactor", the concentration changes of two target components, γ-aminobutyric acid and tartary buckwheat peptide with a molecular weight of less than 1000 Daltons, in the reaction system are monitored in real time by an online near-infrared spectrometer. The monitoring data is input into the process control algorithm in real time. The algorithm dynamically adjusts the temperature, stirring rate and pH value of the reactor based on the real-time concentration and change rate of the two target components, so that the reaction process always moves in the direction of maximizing the synthesis of γ-aminobutyric acid and tartary buckwheat peptide. The compound microbial agent is a co-culture of Lactobacillus plantarum and Streptococcus thermophilus, with a live bacteria ratio of 1:1-2; the compound enzyme preparation contains cellulase, pectinase and neutral protease.

[0019] The process control algorithm is based on the principle of fuzzy PID control. Its core control rules include: when the rate of increase of γ-aminobutyric acid concentration is lower than the preset threshold A, the algorithm outputs a command to increase the reaction temperature by 0.5-1.5℃ within the set range; when the concentration of small molecule tartary buckwheat peptide reaches the plateau period, the algorithm outputs a command to adjust the pH value downward by 0.2-0.4 units to promote protease activity.

[0020] S6. After the reaction is completed, the mixture is inactivated, centrifuged, and the supernatant is filtered through a membrane. The filtrate is then concentrated under vacuum and spray-dried at low temperature to obtain the instant buckwheat tea powder.

[0021] In this specific embodiment, the membrane filtration uses an ultrafiltration membrane with a molecular weight cutoff of 5000 Daltons; the inlet air temperature of the low-temperature spray drying is 85-95℃, and the outlet air temperature is 45-55℃.

[0022] Furthermore, the endpoint of the simultaneous fermentation and enzymatic hydrolysis reaction is determined by the dynamic optimization model according to the following rules: when the concentration of γ-aminobutyric acid increases below 0.05 mg / g / h for three consecutive monitoring periods, and the proportion of small molecule buckwheat peptides reaches a plateau of 65%-75% of the total peptide content, the model issues a termination command.

[0023] Using the method for preparing instant buckwheat tea powder in this embodiment, the present invention effectively protects the heat-sensitive active substances in buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves through low-temperature roasting in an inert carbon dioxide atmosphere, vacuum freeze-drying, and low-frequency pulsed electric field treatment; stabilizes the key components of Astragalus membranaceus and Eucommia ulmoides male flowers using β-cyclodextrin encapsulation technology, reducing processing losses; extracts flavor substances using subcritical water extraction technology, and promotes the synergistic release and fusion of multiple functional components through simultaneous fermentation and enzymatic hydrolysis; and finally, through low-temperature spray drying and other processes, significantly improves the solubility, stability, and overall quality of the product while maximizing the preservation of active ingredients and flavor, solving the technical problems of easy destruction of active ingredients, loss of volatile substances, and difficulty in effectively integrating multiple raw materials in traditional processes.

[0024] It also includes a blockchain-based notarization step for the preparation process data: The time series data of γ-aminobutyric acid concentration, tartary buckwheat peptide concentration, and key by-product concentration collected by the online component monitoring unit, along with the control command parameters of each round output by the dynamic optimization model, are packaged together to generate a process data block with a timestamp. The process data blocks are hashed and then stored in a blockchain network based on a consortium blockchain architecture for evidence preservation, ensuring the immutability and traceability of the preparation process data. Furthermore, complete historical batch preparation process data are periodically extracted from the blockchain network to form a multi-dimensional process dataset. The dataset was trained using a hybrid data mining model based on random forest regression and long short-term memory network to uncover the deep nonlinear relationship between key process parameters (temperature, pH, stirring rate) and core target indicators (final yield of γ-aminobutyric acid, proportion of small molecule peptides, and peak concentration of by-products). The optimization rules and parameter combinations discovered by the data mining model are fed back as prior knowledge to the reward function and policy network of the dynamic optimization model for iterative updates, thereby achieving adaptive evolution of the process control algorithm.

[0025] Example 1: In this example, the preparation method includes the following: S1. Tartary buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves are pretreated separately. After being washed, the tartary buckwheat grains are roasted at low temperature under an inert carbon dioxide atmosphere. Eucommia ulmoides leaves and mulberry leaves are freeze-dried under vacuum and then treated with a low-frequency pulse electric field. S2. After pulverizing the Astragalus membranaceus slices, mix them with Eucommia ulmoides male flowers at a weight ratio of 1:1, embed them with β-cyclodextrin aqueous solution, and then vacuum low temperature drying to obtain the embedded mixture. S3. Mix honeysuckle, dandelion and mint leaves in a weight ratio of 2:2:1, and use subcritical water extraction technology to obtain flavor functional extracts, which are then concentrated for later use. S4. Mix the pretreated buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves in a weight ratio of 75:10:5, crush them, and then mix them with water to make a slurry. S5. Simultaneously add the encapsulation mixture, flavor functional extract, compound microbial agent and compound enzyme preparation to the slurry, and carry out simultaneous fermentation and enzymatic hydrolysis in an integrated reactor. S6. After the reaction is completed, the mixture is inactivated, centrifuged, and the supernatant is filtered through a membrane. The filtrate is then concentrated under vacuum and spray-dried at low temperature to obtain the instant buckwheat tea powder.

[0026] Example 2: In this example, the preparation method includes the following: S1. Tartary buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves are pretreated separately. After being washed, the tartary buckwheat grains are roasted at low temperature under an inert carbon dioxide atmosphere. Eucommia ulmoides leaves and mulberry leaves are freeze-dried under vacuum and then treated with a low-frequency pulse electric field. S2. After pulverizing the Astragalus membranaceus slices, mix them with Eucommia ulmoides male flowers at a weight ratio of 1:2, embed them with β-cyclodextrin aqueous solution, and then perform vacuum low-temperature drying to obtain the embedded mixture. S3. Mix honeysuckle, dandelion and mint leaves in a weight ratio of 2:2:1, and use subcritical water extraction technology to obtain flavor functional extracts, which are then concentrated for later use. S4. Mix the pretreated buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves in a weight ratio of 80:12.5:7.5, crush them, and then mix them with water to make a slurry. S5. Simultaneously add the encapsulation mixture, flavor functional extract, compound microbial agent and compound enzyme preparation to the slurry, and carry out simultaneous fermentation and enzymatic hydrolysis in an integrated reactor. S6. After the reaction is completed, the mixture is inactivated, centrifuged, and the supernatant is filtered through a membrane. The filtrate is then concentrated under vacuum and spray-dried at low temperature to obtain the instant buckwheat tea powder.

[0027] Example 3: In this example, the preparation method includes the following: S1. Tartary buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves are pretreated separately. After being washed, the tartary buckwheat grains are roasted at low temperature under an inert carbon dioxide atmosphere. Eucommia ulmoides leaves and mulberry leaves are freeze-dried under vacuum and then treated with a low-frequency pulse electric field. S2. After pulverizing the Astragalus membranaceus slices, mix them with Eucommia ulmoides male flowers at a weight ratio of 1:3, embed them with β-cyclodextrin aqueous solution, and then vacuum low temperature drying to obtain the embedded mixture; S3. Mix honeysuckle, dandelion and mint leaves in a weight ratio of 2:2:1, and use subcritical water extraction technology to obtain flavor functional extracts, which are then concentrated for later use. S4. Mix the pretreated buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves in a weight ratio of 85:15:10, crush them, and then mix them with water to make a slurry. S5. Simultaneously add the encapsulation mixture, flavor functional extract, compound microbial agent and compound enzyme preparation to the slurry, and carry out simultaneous fermentation and enzymatic hydrolysis in an integrated reactor. S6. After the reaction is completed, the mixture is inactivated, centrifuged, and the supernatant is filtered through a membrane. The filtrate is then concentrated under vacuum and spray-dried at low temperature to obtain the instant buckwheat tea powder.

[0028] This invention also provides an instant buckwheat tea powder, prepared using the method described above. The instant buckwheat tea powder contains γ-aminobutyric acid (GABA) at a content of not less than 2.0 mg / g, and buckwheat peptides with a molecular weight of less than 1000 Daltons account for not less than 60% of the total peptide content.

[0029] The above-disclosed embodiments are merely one or more preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that all or part of the processes for implementing the above embodiments and equivalent changes made in accordance with the claims of this application still fall within the scope of this application.

Claims

1. A method for preparing instant buckwheat tea powder, characterized in that, include: Buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves were pretreated separately. After being washed, the buckwheat grains were roasted at low temperature under an inert carbon dioxide atmosphere. Eucommia ulmoides leaves and mulberry leaves were freeze-dried under vacuum and then treated with a low-frequency pulse electric field. After pulverizing the Astragalus membranaceus slices, they were mixed with Eucommia ulmoides male flowers at a weight ratio of 1-3:1, and then encapsulated with β-cyclodextrin aqueous solution. After vacuum low-temperature drying, the encapsulated mixture was obtained. Honeysuckle, dandelion and mint leaves were mixed in a weight ratio of 2:2:1, and flavor functional extracts were obtained by subcritical water extraction technology, which were then concentrated for later use. Pretreated buckwheat grains, Eucommia ulmoides leaves, and mulberry leaves are mixed in a weight ratio of 75-85: 10-15: 5-10, pulverized, and then mixed with water to make a slurry. Simultaneous addition of an encapsulation mixture, flavor functional extracts, compound microbial agents, and compound enzyme preparations to the slurry, followed by simultaneous fermentation and enzymatic hydrolysis in an integrated reactor; After the reaction is complete, the mixture is inactivated, centrifuged, and the supernatant is filtered through a membrane. The filtrate is then concentrated under vacuum and spray-dried at low temperature to obtain the instant buckwheat tea powder.

2. The method for preparing instant buckwheat tea powder as described in claim 1, characterized in that, The low-temperature roasting conditions for buckwheat grains are as follows: under a carbon dioxide atmosphere, the temperature is increased from room temperature to 95-110℃ at a rate of 3-5℃ / min and held for 15-25 minutes. The low-frequency pulsed electric field treatment parameters for Cyclocarya paliurus leaves and mulberry leaves are: field strength 15-30 kV / cm, pulse frequency 50-200Hz, and treatment time 5-15 minutes.

3. The method for preparing instant buckwheat tea powder as described in claim 2, characterized in that, In the step of "simultaneously adding compound microbial agent and compound enzyme preparation to the slurry and carrying out simultaneous fermentation and enzymatic hydrolysis reaction in an integrated reactor", the concentration changes of two target components, γ-aminobutyric acid and tartary buckwheat peptide with a molecular weight of less than 1000 Daltons, in the reaction system are monitored in real time by an online near-infrared spectrometer. The monitoring data is input into the process control algorithm in real time. The algorithm dynamically adjusts the temperature, stirring rate and pH value of the reactor based on the real-time concentration and change rate of the two target components, so that the reaction process always moves in the direction of maximizing the synthesis of γ-aminobutyric acid and tartary buckwheat peptide. The compound microbial agent is a co-culture of Lactobacillus plantarum and Streptococcus thermophilus, with a live bacteria ratio of 1:1-2; the compound enzyme preparation contains cellulase, pectinase and neutral protease.

4. The method for preparing instant buckwheat tea powder as described in claim 3, characterized in that, The process control algorithm is based on the principle of fuzzy PID control. Its core control rules include: when the rate of increase of γ-aminobutyric acid concentration is lower than the preset threshold A, the algorithm outputs a command to increase the reaction temperature by 0.5-1.5℃ within the set range; when the concentration of small molecule tartary buckwheat peptide reaches the plateau period, the algorithm outputs a command to adjust the pH value downward by 0.2-0.4 units to promote protease activity.

5. The method for preparing instant buckwheat tea powder as described in claim 4, characterized in that, The membrane filtration uses an ultrafiltration membrane with a molecular weight cutoff of 5000 Daltons; the inlet air temperature of the low-temperature spray drying is 85-95℃, and the outlet air temperature is 45-55℃.

6. The method for preparing instant buckwheat tea powder as described in claim 5, characterized in that, The endpoint of the simultaneous fermentation and enzymatic hydrolysis reaction is determined by the dynamic optimization model according to the following rules: when the concentration of γ-aminobutyric acid increases below 0.05 mg / g / h for three consecutive monitoring periods, and the proportion of small molecule buckwheat peptides reaches a plateau of 65%-75% of the total peptide content, the model issues a termination command for the reaction.

7. An instant buckwheat tea powder, prepared by the method for preparing instant buckwheat tea powder as described in claim 6, characterized in that, The instant buckwheat tea powder contains γ-aminobutyric acid (GABA) at a content of not less than 2.0 mg / g, and buckwheat peptides with a molecular weight of less than 1000 Daltons account for not less than 60% of the total peptide content.

Images