Preparation method of soluble sugar substitute based on Jinxiu sweet tea pigment
By using compound enzymatic hydrolysis and membrane separation technology to extract sweetness and pigments from Jinxiu sweet tea, a soluble sugar substitute with high sweetness and stable color was prepared. This solved the shortcomings of existing technologies in separating sweeteners and pigments, and met the demand for natural, healthy, and functional beverage ingredients.
Patent Information
- Application Number
- CN202610128412.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-29
- Publication Date
- 2026-04-14
AI Technical Summary
Existing technologies have failed to systematically extract sweet and coloring components from Jinxiu sweet tea, resulting in the inability to provide natural soluble sugar substitutes with both high sweetness and good coloring in the beverage industry, thus failing to meet the market demand for healthy, natural, and functional products.
A soluble sugar substitute with high sweetness and good coloring was prepared by using a combined enzymatic hydrolysis and hot water extraction technology, combined with green membrane separation and stabilization formulation. The cell wall structure was destroyed by enzymatic hydrolysis of cellulase, pectinase and β-glucosidase, followed by the separation of impurities using microfiltration and nanofiltration membranes, and finally the addition of stabilizers and excipients for spray drying.
It achieves efficient extraction of catechins and stable presence of theaflavins and thearubigins. The product has a sweetness 150-300 times that of sucrose, presents a stable brownish-red color, dissolves rapidly, and maintains stable sweetness and color in common environments, meeting the high standards of the beverage industry.
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Figure CN121845222A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of food processing and natural product extraction technology, specifically to a method for preparing a soluble sugar substitute based on Jinxiu sweet tea pigment. Background Technology
[0002] With the increasing global awareness of healthy eating, consumers are increasingly concerned about excessive sugar intake in food and beverages, making low-sugar and sugar-free options an irreversible market trend. Against this backdrop, the need for healthier transformation of popular drinks such as milk tea is urgent, and the market demand for high-performance sugar substitutes is growing rapidly.
[0003] Currently, sweetening solutions for beverages such as milk tea mainly rely on two categories of products: one is high-intensity synthetic sweeteners, represented by aspartame, sucralose, and acesulfame potassium. While these products have the advantages of high sweetness and zero calories, their "artificially synthesized" nature contradicts the current consumer trend of "clean label" products, and the long-term safety of some products still raises public concerns and controversies, affecting their application in high-end products that pursue a natural and healthy positioning. The other category is natural high-intensity sweeteners, represented by steviol glycosides and mogrosides. These are derived from plants and are more readily accepted for their safety, but they are usually white to light yellow powders, and their solutions are almost colorless. When applied to milk tea, they cannot give the product the iconic reddish-brown or brownish-red color that consumers expect, and manufacturers still need to add food colorings such as caramel coloring for color adjustment. This not only increases the complexity of ingredients and raises production costs, but also makes the product's ingredient list less concise, falling short of the ultimate goal of "clean label" products.
[0004] Jinxiu sweet tea (Rubus suavissimus S. Lee) is a unique medicinal and edible plant resource in Guangxi. Its leaves are rich in Rubusoside, which is 200-300 times sweeter than sucrose, with a pure sweetness and very weak bitterness aftertaste, making it a highly promising source of natural high-intensity sweet substances. More importantly, during processing (such as fermentation and heat treatment), Jinxiu sweet tea leaves can generate polyphenol oxidized polymers such as theaflavins and thearubigins, which are the main components of the color of high-quality black tea.
[0005] Existing technologies have focused on extracting catechins from Jinxiu sweet tea as a single sweetener or evaluating its sweetness characteristics. However, these approaches only consider it as a single source of sweetness and do not systematically consider and utilize its coexisting natural pigment components. Currently, there is a lack of a technical solution that can synergistically and efficiently extract both sweet and pigment components from Jinxiu sweet tea and process them into a stable and easy-to-use compound food ingredient. This traditional approach of "separating sugar and color" fails to fully realize the comprehensive value of Jinxiu sweet tea as a unique resource and also fails to address the urgent need in the beverage industry for novel ingredients that are "natural, healthy, and functionally complex."
[0006] Therefore, we need to develop a natural soluble sugar substitute that can simultaneously utilize the sweetness and color of Jinxiu sweet tea to prepare products with both high sweetness and good coloring power. Summary of the Invention
[0007] In order to solve the problems of the prior art, the present invention provides a method for preparing a soluble sugar substitute based on Jinxiu sweet tea pigment.
[0008] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: Firstly, a method for preparing a soluble sugar substitute based on Jinxiu sweet tea pigment, comprising the following steps: S1: Raw material pretreatment: Wash, dry and pulverize Jinxiu sweet tea leaves to obtain Jinxiu sweet tea powder; S2: Compound enzymatic hydrolysis: Mix the Jinxiu sweet tea powder with water, adjust the pH to 4.5-5.5, and add a compound enzyme for enzymatic hydrolysis; the compound enzyme contains cellulase, pectinase and β-glucosidase; S3: Hot water extraction: The mixture after enzymatic hydrolysis is heated to 85-95℃ for extraction, followed by solid-liquid separation to obtain a primary extract; S4: Membrane separation and concentration: The primary extract is subjected to microfiltration and nanofiltration or reverse osmosis in sequence to obtain Jinxiu sweet tea pigment sweet concentrate; S5: Stabilization and formulation: Add a stabilizer to the concentrate obtained in step S4, wherein the stabilizer is selected from at least one of vitamin C, sodium D-isoascorbate, and β-cyclodextrin; S6: Drying: Spray dry the prepared concentrate to obtain powdered soluble sugar substitute based on Jinxiu sweet tea pigment.
[0009] This process utilizes a combination of enzymatic hydrolysis and hot water extraction to efficiently release sweet glycosides and natural pigments from Jinxiu sweet tea leaves. The leaves are then refined and concentrated using green membrane separation technology, removing impurities and preserving flavor under gentle conditions. Finally, stabilization, blending, and spray drying yield a powder product with excellent solubility and stable color. This technology achieves integrated extraction and fixation of sweet and pigment components, with a simple production process suitable for large-scale production.
[0010] In one specific embodiment of the first aspect, in step S1, the pulverized material is passed through a 40-100 mesh sieve; Grinding tea leaves to 40-100 mesh helps increase the contact area, allowing for more thorough and uniform enzymatic hydrolysis and extraction, thus improving the extraction efficiency of the target components.
[0011] In one specific embodiment of the first aspect, in step S2, the mass ratio of the Jinxiu sweet tea powder to water is 1:10 to 1:30; in the compound enzyme, the mass ratio of cellulase, pectinase and β-glucosidase is 1:1:0.5 to 2:2:1; the enzymatic hydrolysis temperature is 45-60℃, and the enzymatic hydrolysis time is 1-3 hours. By controlling the material-to-liquid ratio, enzyme ratio, and decomposition temperature and time, the cell wall structure can be effectively destroyed, promoting the dissolution of sweet and pigment substances. At the same time, the flavor can be improved and the off-flavors of herbs can be reduced through the action of β-glucosidase.
[0012] In one specific embodiment of the first aspect, in step S4, the microfiltration uses a microfiltration membrane with a pore size of 0.1-0.5 μm; the nanofiltration uses a nanofiltration membrane with a molecular weight cutoff of 200-500 Da. By using microfiltration membranes with specific pore sizes and nanofiltration membranes with specific molecular weight cutoffs, large molecular impurities (such as pectin and protein) can be accurately separated and target small molecular components can be concentrated, avoiding the destruction of heat-sensitive substances and resulting in a purer product taste.
[0013] In one specific embodiment of the first aspect, in step S5, an excipient is further added, wherein the excipient is selected from at least one of maltodextrin and resistant dextrin; Adding excipients such as maltodextrin can increase the solid content of the concentrate, improve the powdering properties and product yield during spray drying, and enhance the flowability and solubility of the final product.
[0014] In one specific embodiment of the first aspect, in step S6, the inlet air temperature of the spray dryer is 160-185°C, and the outlet air temperature is 80-95°C. Drying at suitable inlet and outlet air temperatures can effectively prevent the degradation of heat-sensitive components, ensure that the product's moisture content meets standards, maintains stable color, and produces uniform powder particles, making it easy to store and use.
[0015] Secondly, a soluble sugar substitute based on Jinxiu sweet tea pigment prepared by a method for preparing a soluble sugar substitute based on Jinxiu sweet tea pigment. The soluble sugar substitute produced by the above method has a sweetness level 150-300 times that of sucrose, and because it fully retains the natural pigments of Jinxiu sweet tea, the product exhibits a stable brownish-red color. This product has a low moisture content (≤5%), dissolves rapidly, and is a composite food ingredient that combines high-intensity sweetness with natural coloring, achieving a dual effect in one product.
[0016] In one specific embodiment of the second aspect, the sweetness is 150-300 times that of sucrose, and it is a brownish-red powder with a moisture content of ≤5%.
[0017] Thirdly, the application of soluble sugar substitutes as sweeteners and colorants in food or beverage preparation; This soluble sugar substitute can be used as a sweetener and colorant in various food and beverage products. Adding it to drinks such as milk tea and coffee not only provides a pure sweetness but also imparts a naturally appealing reddish-brown color, simplifying the formula and reducing the need for artificial colorings.
[0018] Fourthly, a milk tea product comprising tea base, milk base, and soluble sugar substitute; Milk tea products containing this soluble sugar substitute derive their sweetness from natural sources and their color from the plants themselves, eliminating the need for additional coloring agents such as caramel coloring. The products offer a harmonious flavor and a naturally stable color, satisfying consumers' demand for healthy, natural milk tea while reducing the complexity of ingredient production.
[0019] The beneficial effects of this invention are as follows: 1. In terms of preparation process, the use of a combined enzymatic hydrolysis and hot water extraction technique effectively disrupts the cell wall structure of Jinxiu sweet tea leaves, significantly improving the extraction rate of catechins and pigments. The subsequent low-temperature membrane separation and concentration process achieves efficient enrichment of target small molecules and selective separation of large molecular impurities and some small-molecule bitter substances (such as specific catechins) at room temperature, avoiding the damage of heat-sensitive active ingredients to high temperatures throughout the process, thus ensuring the purity of the product flavor while improving yield. Finally, by constructing a dual stabilization system combining chemical antioxidation and physical encapsulation, and optimizing spray drying parameters, the liquid extract was successfully converted into a powder product with high physical stability and excellent solubility. The entire process is mild, green, and efficient. 2. In terms of product performance, this soluble sugar substitute achieves an integrated sweetness and coloring function. Its core sweetener, betaine, is retained at a high concentration, achieving a sweetness 150-300 times that of sucrose. Simultaneously, the stable presence of natural pigments such as theaflavins and thearubigins in the product gives it a stable brownish-red color. The product has a low moisture content (≤5%), dissolves rapidly, and due to its unique stabilization system, its sweetness intensity and color remain highly stable even under the heat, light, and oxygen environments commonly encountered in food processing, meeting the high standards for functional ingredients in the beverage, baking, and other food industries. Attached Figure Description
[0020] Figure 1 This is a flowchart of the intelligent agent manufacturing process of the present invention; Figure 2 This is a schematic diagram comparing the enzymatic hydrolysis effects of the present invention. Detailed Implementation
[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0022] Please refer to Figures 1 to 2 shown.
[0023] Example 1: Preparation of soluble sugar substitute based on Jinxiu sweet tea pigment.
[0024] This embodiment describes in detail the optimal preparation process of the present invention.
[0025] (1) Raw material pretreatment: Take 1.0 kg of fresh Jinxiu sweet tea leaves (Rubus suavissimus S. Lee) from Guangxi, rinse with purified water to remove surface dust and impurities, drain, and then dry in a 50℃ hot air circulating oven until constant weight (moisture content ≤8%). Grind the dried tea leaves in a universal grinder and pass through a 60-mesh standard sieve (approximately 0.25 mm aperture) to obtain uniformly sized Jinxiu sweet tea powder. Purpose: Controlling the particle size of the raw material facilitates uniform penetration of enzymes and water, improving extraction efficiency.
[0026] (2) Compound enzymatic hydrolysis: The tea powder was thoroughly mixed with 20 kg (1:20 by mass) of 40°C pure water in a reactor equipped with stirring and temperature control. The pH of the mixture was slowly adjusted to 5.0 using a 10% food-grade citric acid solution. Then, a compound enzyme preparation was precisely added: 5.0 g of cellulase (100,000 U / g), 5.0 g of pectinase (50,000 U / g), and 2.5 g of β-glucosidase (20,000 U / g), in a mass ratio of 2:2:1. Enzymatic hydrolysis was carried out at a constant temperature of 50±1°C and a stirring speed of 80 rpm for 2 hours. Technical effects and mechanism: The synergistic effect of cellulase and pectinase efficiently degrades the cellulose skeleton and pectin layer of the tea cell wall, disrupting its dense structure and significantly increasing the dissolution channels of the contents. β-glucosidase can specifically hydrolyze flavonoid glycosides, aroma precursor glycosides, and other substances, releasing free volatile aroma components (such as linalool and geraniol), thereby effectively improving the overall flavor characteristics of the product. At the same time, by hydrolyzing certain polyphenol aglycones, this enzyme promotes the oxidative polymerization reaction of aglycones during subsequent hot water extraction, which is beneficial to the generation and accumulation of stable pigments such as theaflavins and thearubigins, achieving the dual effect of flavor enhancement and color improvement.
[0027] (3) Hot water extraction: After enzymatic hydrolysis, the reaction system temperature was rapidly raised to 90±2℃ using a jacketed steam generator, and maintained at this temperature while stirring at 60 rpm for 60 minutes. This process utilizes high temperature to fully dissolve the sweet tea glycosides (the main sweet component) and polyphenol oxidized polymers (theaflavins, thearubigins, and other pigments) released from the cells. Immediately after extraction, a plate and frame filter press with a 200-mesh nylon filter cloth was used for hot filtration to separate the tea residue, yielding approximately 19.5 L of clear, reddish-brown extract.
[0028] (4) Membrane separation and concentration: The extract was first pumped into a microfiltration system equipped with a 0.2 μm ceramic membrane for cross-flow filtration at an operating pressure of 0.3 MPa and room temperature. This step effectively retained residual plant fiber particles, colloids, starch, and some large protein molecules in the extract, resulting in a highly clear permeate. Subsequently, the permeate was introduced into a spiral-wound aromatic polyamide nanofiltration membrane system with a molecular weight cutoff of 300 Da, and concentrated at 2.0 MPa pressure and 25-30°C. Concentration was stopped when the liquid volume was reduced to approximately 1 / 5 of its original volume (approximately 4 L), at which point the solids content (measured by refractometer) of the concentrate was 25.2%. Technical advantages: The entire process utilizes low-temperature membrane separation technology, replacing traditional high-temperature evaporation, thus minimizing the thermal degradation and inactivation of heat-sensitive sweet components (stevia glycosides) and natural pigments. The microfiltration-nanofiltration combined process can selectively separate and remove large molecular colloids, proteins, and some small molecular bitter substances from the extract while clarifying and concentrating it, especially catechin monomers with molecular weight in the range of 200-500 Da (such as epigallocatechin gallate, EGCG), thereby significantly reducing the astringency of the final product, making the sweetness purer and the taste smoother.
[0029] (5) Stabilization and blending: Take 4000g of the above nanofiltration concentrate and, under gentle stirring (45℃), add the following ingredients in sequence (all calculated based on the mass of the concentrate): Stabilizer: Ascorbic acid (vitamin C) 20.0g (0.5%), used for anti-oxidation to prevent pigment oxidation and fading; Stabilizer: β-cyclodextrin 40.0g (1.0%), as a molecular encapsulating agent, encapsulates glycosides and flavor molecules, enhances their stability to light, heat and oxygen, and helps to mask trace amounts of aftertaste bitterness; Excipient: 200.0g (5.0%) of maltodextrin, used to increase the solid content of the system, adjust the viscosity of the material, significantly improve the powdering properties and product yield of subsequent spray drying, and give the final product good flowability.
[0030] Continue stirring for 30 minutes to ensure all additives are completely dissolved and mixed evenly.
[0031] Mechanism of action: Vitamin C, as a strong reducing agent, can be preferentially oxidized, thus effectively preventing the oxidative browning of sweet tea pigments (theaflavins and thearubigins). The hydrophobic cavity of β-cyclodextrin can form inclusion complexes with sweet tea glycosides and flavor molecules, physically isolating the core functional molecules from direct attack by light and oxygen, significantly enhancing their environmental stability, and helping to mask trace amounts of aftertaste bitterness. Vitamin C (chemical antioxidant) and β-cyclodextrin (physical encapsulation) constitute a dual synergistic stabilizing system, providing comprehensive protection to heat, light, and oxygen-sensitive components far exceeding that of a single stabilizer. Maltodextrin, as an excipient, mainly plays a role in increasing the solids content of the system, adjusting viscosity, improving drying processes, and enhancing the physical properties of the final product.
[0032] (6) Drying: The homogenized concentrate was then fed into a centrifugal spray drying tower. Key process parameters were set as follows: inlet air temperature 175±5℃, outlet air temperature 85±5℃, feed flow rate 25L / h, and atomizer speed 18000rpm. After drying, the product was collected by a cyclone separator to obtain a fine, uniform brownish-red powder. The product was immediately sealed in nitrogen-filled aluminum foil bags and stored away from light.
[0033] (7) Product testing and characterization: The prepared sugar substitute powder was tested for multiple indicators: Sweetness determination: Following the industry consensus method of GB / T 5009.7, using a 10% sucrose solution as the standard, the sweetness was evaluated by 10 trained sensory evaluators. The results showed that its sweetness was approximately 220 times that of sucrose.
[0034] Analysis of main components: Using high performance liquid chromatography, the content of stevia (the main sweet substance) in the product was determined to be 82.5%, and the total content of theaflavins and thearubigins was 3.8%.
[0035] Moisture content: Determined by direct drying method according to GB 5009.3, the moisture content of the product is 3.2% (≤5%).
[0036] Color quantification: The powder color was measured using a colorimeter (CIE L*a*b system), and the results showed L=46.3 (lightness), a*=+24.8 (redness), and b*=+16.5 (yellowness), which objectively characterized its stable brownish-red color.
[0037] Solubility: At room temperature, 1g of the product dissolves completely in 50mL of water within 30 seconds, leaving a clear and transparent solution without any precipitate.
[0038] Example 2: Verification of process parameter range.
[0039] This embodiment aims to illustrate that by adjusting the process within the parameter range of this method, it is still possible to implement the method and obtain qualified products.
[0040] (1) The raw material pretreatment is the same as in Example 1, but after crushing, it is passed through an 80-mesh sieve.
[0041] (2) In the compound enzymatic hydrolysis step, the mass ratio of tea powder to water was adjusted to 1:15, and the pH was adjusted to 4.8. The amount of compound enzyme added was adjusted to: 3g of cellulase, 3g of pectinase, and 1.5g of β-glucosidase (mass ratio 2:2:1). Enzymatic hydrolysis was carried out at 55℃ for 1.5 hours.
[0042] (3) The hot water extraction temperature was adjusted to 88℃ and the time was 75 minutes.
[0043] (4) In the membrane separation step, microfiltration uses a 0.1 μm organic microfiltration membrane and nanofiltration uses a nanofiltration membrane with a molecular weight cutoff of 200 Da for concentration.
[0044] (5) In the stabilization process, sodium D-isoascorbate (0.6%) and resistant dextrin (6%) were used for formulation.
[0045] (6) The inlet air temperature of the spray dryer is set to 165℃ and the outlet air temperature is 90℃.
[0046] Results: The obtained product was also a brownish-red powder. Tests showed that its sweetness was about 200 times that of sucrose, with a catechin content of ≥78% and a moisture content of 4.1%.
[0047] Example 3: Comparison of product application and overall effect.
[0048] This embodiment demonstrates the comprehensive advantages of the present invention through specific applications and quantitative comparisons.
[0049] 1. Application example: Milk tea preparation.
[0050] To prepare 500mL of milk tea: Take 300mL of black tea (brewed with 5g of black tea), 100mL of whole milk, add 0.11g (calculated according to sweetness) of the sugar substitute powder prepared in Example 1, and stir to dissolve.
[0051] 2. Scale settings.
[0052] Comparative Example A (Synthesis Scheme): Prepare the same milk tea, using 0.044g of sucralose (approximately 500 times sweeter than sucrose) to provide equivalent sweetness, and add 0.5mL of caramel coloring solution (color rate EBC20000) to adjust to a similar color.
[0053] Comparative Example B (Natural Separation Solution): Prepare the same milk tea, using 0.088g of steviol glycosides (approximately 250 times sweeter than sucrose) to provide equivalent sweetness, and add 0.5mL of caramel coloring solution for coloring.
[0054] 3. Comparison of tests and data.
[0055] Color stability test: Three groups of milk tea samples were placed in transparent glass bottles and heated in an 80℃ water bath for 30 minutes. The color difference (ΔE) before and after heating was measured using a colorimeter. Results: The product of this invention showed ΔE=1.8, Comparative Example A showed ΔE=3.5, and Comparative Example B showed ΔE=4.1. The data shows that the product of this invention has significantly better color stability under thermal conditions than the control group with added caramel color.
[0056] Sensory Evaluation: Ten professional sensory evaluators conducted a blind taste test (5 points being the highest) on three indicators: "purity of sweetness," "off-flavor (bitter / metallic aftertaste)," and "naturalness of color" for the three groups of milk teas. The average score was then calculated. The product of this invention has the following characteristics: sweetness purity 4.6, off-odor degree 4.8 (almost no off-odor), and natural color 4.7.
[0057] Comparative Example A: Sweetness purity 3.5, off-flavor degree 3.0 (slight metallic aftertaste), color naturalness 3.8 (color appears slightly dull).
[0058] Comparative Example B: Sweetness purity 4.0, off-flavor degree 3.5 (slight licorice aftertaste), color naturalness 3.8.
[0059] Clean labeling and convenience: This invention requires only one ingredient, which can be labeled as "Golden Soo Sweet Tea Extract"; while comparative examples A and B both require two or more additives, resulting in complex compositions. In production, this invention simplifies the weighing and dispensing processes, reducing the error rate.
[0060] Comparative Example C: Comparison of single hot water extraction processes.
[0061] 1. Experimental Design: This comparative example aims to investigate whether a similar technical effect to the complete process of this invention can be obtained solely through hot water extraction without performing complex enzymatic hydrolysis. Except for omitting the enzymatic hydrolysis step, all other process parameters, raw material batches, equipment, and subsequent treatments were kept completely consistent with "Example 1" to ensure the reliability and comparability of the experimental results.
[0062] 2. Specific operations: (1) Raw material pretreatment: Same as step (1) in Example 1, take an equal amount (1.0 kg) of the same batch of Jinxiu sweet tea leaves and crush them through a 60-mesh sieve.
[0063] (2) Eliminate the enzymatic hydrolysis step: Mix the tea powder directly with 20 kg of pure water and adjust the pH to 5.0 with citric acid. Do not add any compound enzymes.
[0064] (3) Hot water extraction: The mixture was directly heated to 90°C and kept warm for 60 minutes (the extraction time is different from the total treatment time of Example 1, which is “2 hours of enzymatic hydrolysis + 1 hour of extraction”. For fair comparison, an additional comparison with extended extraction time was set up in this comparative example, as shown in the analysis below).
[0065] (4) Subsequent steps: after extraction, solid-liquid separation, membrane separation and concentration, stabilization and formulation (using the same type and amount of stabilizer and excipient), spray drying, etc., all strictly follow the parameters of Example 1.
[0066] (5) Key adjustment group: For a more comprehensive comparison, a comparative example C1 was added: while canceling enzymatic hydrolysis, the hot water extraction time was extended to 3 hours (i.e. the total treatment time was equivalent to 3 hours in Example 1) to examine whether simply extending the hot soaking time could replace the effect of enzymatic hydrolysis.
[0067] 3. Comparison of data and results analysis: Parallel testing was conducted on the products obtained from Example 1, Comparative Example C (extraction for 1 hour), and Comparative Example C1 (extraction for 3 hours). The core data comparison is as follows: The comparative data clearly show that: Efficiency Advantage: The compound enzymatic hydrolysis step employed in this invention significantly improves the extraction efficiency and final product yield of the target products (stevia glycosides and pigments). Even though Comparative Example C1 attempted to compensate by extending the hot soaking time by three times, its extraction rate was still lower than that of the complete process of this invention. This proves that enzymatic hydrolysis is not simply an "auxiliary" step, but a core key technology for achieving high-efficiency and high-selectivity extraction.
[0068] Quality advantages: Enzymatic hydrolysis not only increases yield but also optimizes product quality, resulting in higher purity glycosides, richer pigments, and a purer flavor. This is something that cannot be achieved by a single physical extraction method.
[0069] In summary, the preparation method provided by this invention, through a process of synergistic extraction via compound enzymatic hydrolysis, low-temperature membrane separation and purification, and stabilization of the compound system, successfully produces a soluble sugar substitute from Jinxiu sweet tea leaves that combines high levels of natural sweetness with stable natural pigments. The product exhibits significant advantages in multiple dimensions: natural and clean ingredients, highly efficient and complex functions (integrated sugar and color), excellent flavor and taste, and stable processing performance. The examples and comparative data fully verify the technical effectiveness, inventiveness, and industrial applicability of this invention.
[0070] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a soluble sugar substitute based on Jinxiu sweet tea pigment, characterized in that, Includes the following steps: S1: Raw material pretreatment: Wash, dry and pulverize Jinxiu sweet tea leaves to obtain Jinxiu sweet tea powder; S2: Compound enzymatic hydrolysis: Mix the Jinxiu sweet tea powder with water, adjust the pH to 4.5-5.5, and add a compound enzyme for enzymatic hydrolysis; the compound enzyme contains cellulase, pectinase and β-glucosidase; S3: Hot water extraction: The mixture after enzymatic hydrolysis is heated to 85-95℃ for extraction, followed by solid-liquid separation to obtain a primary extract; S4: Membrane separation and concentration: The primary extract is subjected to microfiltration and nanofiltration or reverse osmosis in sequence to obtain Jinxiu sweet tea pigment sweet concentrate; S5: Stabilization and formulation: Add a stabilizer to the concentrate obtained in step S4, wherein the stabilizer is selected from at least one of vitamin C, sodium D-isoascorbate, and β-cyclodextrin; S6: Drying: Spray dry the prepared concentrate to obtain powdered soluble sugar substitute based on Jinxiu sweet tea pigment.
2. The preparation method according to claim 1, characterized in that, In step S1, the pulverized material is passed through a 40-100 mesh sieve.
3. The preparation method according to claim 1, characterized in that, In step S2, the mass ratio of Jinxiu sweet tea powder to water is 1:10 to 1:30; the mass ratio of cellulase, pectinase and β-glucosidase in the compound enzyme is 1:1:0.5 to 2:2:1; the enzymatic hydrolysis temperature is 45-60℃ and the enzymatic hydrolysis time is 1-3 hours.
4. The preparation method according to claim 1, characterized in that, In step S4, the microfiltration membrane used has a pore size of 0.1-0.5 μm; the nanofiltration membrane used has a molecular weight cutoff of 200-500 Da.
5. The preparation method according to claim 1, characterized in that, In step S5, an excipient is also added, wherein the excipient is selected from at least one of maltodextrin and resistant dextrin.
6. The preparation method according to claim 1, characterized in that, In step S6, the inlet air temperature of the spray dryer is 160-185℃, and the outlet air temperature is 80-95℃.
7. A soluble sugar substitute based on Jinxiu sweet tea pigment, prepared by the method according to any one of claims 1 to 6.
8. The soluble sugar substitute according to claim 7, characterized in that, Its sweetness is 150-300 times that of sucrose, and it is a brownish-red powder with a moisture content of ≤5%.
9. The use of the soluble sugar substitute as a sweetener and colorant in the preparation of food or beverages according to claim 7 or 8.
10. A milk tea product, characterized in that, It contains tea base, milk base, and the soluble sugar substitute as described in claim 7 or 8.