Jasmine flower black tea beverage fermented by kombucha and preparation method thereof

Abstract

This invention proposes a jasmine kombucha fermented beverage and its preparation method, belonging to the field of food fermentation technology and functional beverage development. The preparation method involves: preparing jasmine syrup by combining jasmine flowers with white sugar; then inoculating kombucha bacteria into the jasmine syrup for fermentation, resulting in a jasmine kombucha fermented beverage. Using jasmine flowers as the fermentation raw material solves the technical problem of traditional kombucha using a single raw material. The addition of jasmine flowers enhances the aroma, improves the taste, and increases beneficial components such as crocin, resulting in a better flavor than traditional kombucha beverages. A standardized fermentation process is adopted, including tea syrup preparation, sterilization + sterilization inoculation to ensure pure fermentation, and post-processing to solidify quality and extend shelf life. The finished beverage is of excellent quality, possessing a unique jasmine fragrance, a sweet and sour, smooth taste, and outstanding nutritional value, rich in total phenols and organic acids and other active ingredients.

Description

Technical Field

[0001] This invention belongs to the field of food fermentation technology and functional beverage development, specifically relating to fermented beverages made from jasmine and kombucha and their preparation methods. Background Technology

[0002] Jasmine, a plant belonging to the Oleaceae family and the Jasminum genus, is used both as food and medicine. Rich in various active ingredients, it possesses health benefits such as antioxidant, blood sugar-lowering, and antibacterial properties. Its unique and refreshing aroma makes it a high-quality food ingredient. Kombucha, a natural functional beverage made by the symbiotic fermentation of tea and sugar water using acetic acid bacteria, lactic acid bacteria, and yeast, contains organic acids, vitamins, tea polyphenols, and other nutrients and bioactive substances. It boasts antioxidant, antibacterial, anti-inflammatory, and metabolism-boosting effects, and is experiencing strong growth in the international market. However, traditional kombucha production processes are limited, with black tea as the primary raw material, resulting in a limited range of products that fail to meet diverse consumer demands. Furthermore, my country's kombucha beverage market is still in its early stages, with a lack of product variety, necessitating the development of kombucha fermentation products using novel raw materials.

[0003] In existing technologies, some researchers have explored the development of kombucha beverages using fruits and vegetables as raw materials. For example, the invention patent CN102389134A, "A Kombucha Compound Fermented Beverage and Its Preparation Method," discloses a health beverage fermented using tea, sugar, and water as a culture medium, with the addition of apple juice, carrot juice, and lemon juice, under the action of probiotics in kombucha. The prepared beverage contains the original sugars, amino acids, vitamins, and other nutrients from the fruit juice, as well as the nutrients produced by fermentation and the aroma of alcohols and esters, resulting in a unique flavor. The invention patent CN106173721A, "A Soybean Molasses Kombucha Fermented Beverage and Its Preparation Method," discloses the cultivation of kombucha mother liquor using corn saccharification broth, followed by the use of soybean molasses as a culture medium and kombucha as the inoculum to prepare a novel and distinctive soybean molasses kombucha fermented beverage. The resulting product has a short fermentation time, ideal morphology, and retains the original nutrients and functional components of soybeans and corn.

[0004] However, there is no mature solution for using jasmine as the core ingredient to replace traditional black tea fermentation processes, and there is a lack of precise optimization for the amount of jasmine, kombucha, and white sugar added, resulting in poor flavor harmony and insufficient retention of functional components in the product. Therefore, it is of great significance to develop a method for preparing jasmine kombucha fermented beverages with optimized formula, unique flavor, and both health benefits and industrial value. Summary of the Invention

[0005] To address the problems in existing technologies, this invention proposes a jasmine kombucha fermented beverage. It involves preparing jasmine syrup using Fuzhou jasmine flowers and white sugar, then inoculating kombucha into the jasmine syrup for fermentation. The fermentation process is standardized, including syrup preparation, fermentation, and post-processing. The resulting fermented beverage is of excellent quality and has outstanding nutritional value.

[0006] To achieve the purpose of the invention, the following technical solution is provided: This invention provides a method for preparing a jasmine kombucha fermented beverage. The specific method is as follows: using Fuzhou double-petal jasmine flowers as fermentation raw materials, preparing jasmine tea syrup with white sugar, inoculating kombucha bacteria into the jasmine tea syrup for fermentation, and obtaining a jasmine kombucha fermented beverage.

[0007] Furthermore, a method for preparing a jasmine kombucha fermented beverage includes the following steps: S1. Add jasmine flowers and white sugar to purified water, boil until the white sugar is completely dissolved, let it cool naturally to room temperature, and then filter it through a 100-mesh sterile filter to prepare jasmine tea sugar water. S2. Sterilize the filtered jasmine tea sugar water, inoculate it with kombucha in a sterile environment, seal it with sterile gauze, and ferment it at room temperature for 4 days to obtain jasmine kombucha fermentation liquid. S3. Centrifuge the jasmine kombucha fermentation liquid, take the supernatant and sterilize it again at 80-85℃ for at least 30 minutes, then aseptically heat-bottle and cool it, and store it at 0-4℃ to obtain the jasmine kombucha fermented beverage.

[0008] Furthermore, in step S1, during the preparation of jasmine syrup, the amount of jasmine flowers added is 5 g / L, and the mass fraction of white sugar in the jasmine syrup is 10%.

[0009] Furthermore, in step S2, the inoculation amount of kombucha in the jasmine syrup is 5% by volume.

[0010] The present invention also provides a jasmine kombucha fermented beverage prepared according to the above preparation method.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention proposes a jasmine tea kombucha fermented beverage, using jasmine flowers as the fermentation raw material, replacing the traditional kombucha fermented beverages that mostly use black tea or green tea, thus solving the technical problem of the single raw material in traditional kombucha. Adding jasmine flowers not only enhances the aroma and improves the taste, but also increases beneficial components such as crocin, resulting in a better flavor than traditional kombucha beverages. Furthermore, the precise optimization of the addition amounts of jasmine flowers, kombucha, and white sugar, with 5g / L of jasmine tea, 5% (volume fraction) of kombucha, and 10% (mass fraction) of white sugar, produces a kombucha fermented beverage with a bright, light green color, uniform color, a unique jasmine aroma, a sweet and sour taste, a smooth texture, and stable composition, meeting consumer sensory requirements.

[0012] 2. The preparation method of the jasmine kombucha fermented beverage of the present invention adopts a standardized fermentation process, including key parameters such as tea sugar water preparation, fermentation conditions, and post-processing. The preparation of tea sugar water provides the nutritional and flavor basis for fermentation. Sterilization and aseptic inoculation are used to ensure the purity of the fermentation strain. Fermentation transforms into active ingredients and unique flavor. Post-processing solidifies the quality and extends the shelf life. The prepared jasmine kombucha fermented beverage is rich in active ingredients such as total phenols (22.40 mg / L) and organic acids (total acid content 1.404 g / L), with a stable pH value of around 3.20. It combines the health benefits of jasmine and kombucha, meeting the consumption needs of functional foods.

[0013] 3. The preparation method proposed in this invention has clear formulation content and process parameters, strong repeatability, is suitable for large-scale production, and has controllable production costs, resulting in good economic benefits. Attached Figure Description

[0014] Figure 1 This is a picture of the finished product of the jasmine kombucha fermented beverage in Example 1 of the present invention; Figure 2 This is the effect curve of the amount of jasmine added on the sensory score in Example 1 of the present invention; Figure 3 The curve showing the effect of the amount of kombucha added on the sensory score in Example 1 of this invention; Figure 4 This is the effect curve of the amount of white sugar added on the sensory score in Example 1 of the present invention; Figure 5 This is the total sugar standard curve in Example 1 of the present invention; Figure 6 This is the total phenol standard curve in Example 1 of the present invention. Detailed Implementation

[0015] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Unless otherwise specified, all raw materials used in the following examples were purchased commercially.

[0017] Unless otherwise specified, the methods used in the following embodiments are conventional operating methods in the art.

[0018] The raw materials used in this embodiment of the invention are: commercially available Fuzhou jasmine flowers, commercially available kombucha, white sugar, and Wahaha purified water.

[0019] The reagents used in the embodiments of this invention are: Folin-Ciocalteu, DNS reagent, sodium hydroxide, gallic acid, anhydrous sodium carbonate, glucose solution, and anhydrous ethanol.

[0020] The instruments used in this embodiment of the invention are: constant temperature water bath, ultraviolet-visible spectrophotometer, acid-base burette, pH meter, electronic balance, centrifuge, sterile sieve (100 mesh), and glass bottle.

[0021] Example 1 This embodiment provides a method for preparing a jasmine kombucha fermented beverage, including the following steps: S1: Jasmine tea syrup preparation: Select 5 g of Fuzhou jasmine flowers, sieve out damaged flowers, wash them clean with running water, add 1000 mL of purified water and 100 g of white sugar, boil at 100℃ for 15 min until the white sugar is completely dissolved, cool naturally to room temperature and then filter through a 100 mesh sterile sieve. S2: Sterilization and inoculation: Sterilize the filtered jasmine tea syrup, cool it to room temperature, add 5% (volume fraction) kombucha culture solution on a clean bench, and seal it with sterile gauze; S3: Fermentation culture: Ferment at room temperature for 4 days to obtain jasmine kombucha fermentation liquid; S4: Post-processing: Place the fermentation broth in a centrifuge tube, centrifuge at 4000 r / min for 5 min, and take the supernatant; sterilize at 80-85℃ for 30 min, then aseptically heat-bottle, cool to 37-38℃, and store at 0-4℃ to obtain jasmine kombucha fermented beverage.

[0022] The prepared jasmine kombucha fermented beverage is as follows: Figure 1 As shown, the beverage is light green and bright in color, with no obvious impurities, and has the unique appearance characteristics of jasmine.

[0023] Based on the above method, the sensory evaluation of jasmine kombucha fermented beverages prepared with different amounts of jasmine flowers (1 g / L, 3 g / L, 7 g / L, and 9 g / L) was studied. Figure 2 As shown, with the increase of jasmine flower addition, the sensory score of the jasmine kombucha fermented beverage first increased and then decreased, exhibiting a normal distribution. When the jasmine flower addition was 5 g / L, the sensory score was the highest and the intra-group scoring error was the smallest, indicating relatively reliable data. At this point, the flavor of the jasmine kombucha fermented beverage was optimal. The sensory score bar chart shows that if too little jasmine flower is added, the jasmine aroma will be weak, resulting in poor sensory flavor; if too much jasmine flower is added, the bitterness of jasmine will increase, damaging the product's taste and flavor. Therefore, orthogonal experiments were conducted using three gradients of jasmine flower addition: 3 g / L, 5 g / L, and 7 g / L.

[0024] Based on the above methods, the amount of kombucha added was varied to 1%, 3%, 7%, and 9% to study the effect of the amount of kombucha fermentation broth added on the sensory evaluation of kombucha fermented beverages. Figure 3 As shown, with the increase of kombucha fermentation liquid addition, the sensory score of jasmine kombucha fermented beverage first increased and then decreased, exhibiting a normal distribution. When the kombucha addition was 5%, the sensory score was the highest with small intra-group scoring error, indicating relatively reliable data. At this point, the jasmine kombucha fermented beverage had the best flavor. The sensory score bar chart shows that if the kombucha addition is too small, the jasmine kombucha beverage will be difficult to ferment, resulting in insufficient acidity and a poor taste; if the kombucha fermentation liquid addition is too large, the jasmine kombucha fermentation liquid will have an overly acidic taste, masking the jasmine fragrance and resulting in a poor flavor. Therefore, orthogonal experiments were conducted using three gradients of kombucha fermentation liquid addition: 3%, 5%, and 7%.

[0025] Based on the above method, the amount of added white sugar was varied to 4%, 6%, 8%, and 12% to study the effect of added white sugar on the sensory score of jasmine kombucha fermented beverage. Figure 4 As shown, with the increase of added white sugar, the sensory score of the jasmine kombucha fermented beverage first increased and then decreased, exhibiting a normal distribution. When the added white sugar was 10%, the sensory score was the highest and the intra-group scoring error was the smallest, indicating relatively reliable data. At this point, the flavor of the jasmine kombucha fermented beverage was optimal. If the added white sugar was too little, the jasmine kombucha beverage would be difficult to ferment, and the mycelium would be difficult to form, affecting the formation of the fermented beverage's flavor. Therefore, orthogonal experiments were conducted with three gradients of added white sugar: 8%, 10%, and 12%.

[0026] Twenty evaluators with food expertise were selected to score the samples based on four dimensions: color (20%), odor (20%), taste (40%), and texture (20%). Example 1 achieved a sensory score of 90.8, significantly higher than the other variable groups. Specific quality characteristics are as follows: ① Color: Light green and bright, uniform in color, without any impurities; ②Scent: The jasmine has a rich, fresh fragrance, a pleasant sourness, a harmonious flavor, and no off-odors; ③ Taste: The flavor is a perfect balance of sweet and sour, with a pure taste and a smooth, delicate texture; ④ Organizational state: homogeneous and stable, with a small amount of sedimentation allowed and slight turbidity.

[0027] The appropriate addition ranges for jasmine flowers, kombucha, and white sugar were determined through single-factor experiments, and then L9(3) was used. 4 An orthogonal experiment was conducted, using sensory evaluation as the evaluation standard, to determine the optimal formulation. The factor level table is shown in Table 1.

[0028] Table 1. Orthogonal experimental level table for jasmine kombucha fermented beverage formulation

[0029] Physicochemical index testing: The physicochemical properties of the jasmine kombucha fermented beverage prepared in Example 1 were tested. pH value determination: As shown in Table 2, the pH value of the jasmine kombucha fermented beverage was 3.23, 3.19 and 3.19 for three pH measurements, and the average pH value was 3.20.

[0030] Table 2. pH Measurement Results of Jasmine Kombucha Fermented Beverage

[0031] Total acid content determination: Jasmine kombucha fermented beverage and a blank control group were subjected to acid-base titration using sodium hydroxide as the standard titrant. The required volume of sodium hydroxide standard titrant is shown in Table 3. The experimental results show that the titration values ​​for the jasmine kombucha fermented beverage in three titrations were 2.31, 2.30, and 2.35, respectively. The average value of the three titrations was 2.35. Subtracting the volume of NaOH consumed in the titration of the blank control group from the average value of the three titrations and substituting this into the formula, the total acid content of the jasmine kombucha fermented beverage was found to be 1.404 g / L.

[0032] Table 3 Results of acid-base titration

[0033] Sensory evaluation and determination of total sugar content: The experimental results show the correlation between the absorbance of jasmine kombucha fermented beverage and the total sugar content, as shown in Table 4 below. The total sugar standard curve is shown in... Figure 5 As shown, the horizontal axis represents the total sugar concentration (mg / ml), and the vertical axis represents the absorbance (OD). 540nm The standard curve equation is y = 0.269x - 0.005, R0 2 =0.997); The absorbance values ​​of the jasmine kombucha fermented beverage diluted 10 times are shown in Table 5. From the experimental results, it can be seen that the absorbance values ​​of the jasmine kombucha fermented beverage measured three times were 0.159, 0.153, and 0.156, respectively. The average value of the three titrations is 0.156. Substituting the average absorbance value measured in the experiment into the total sugar calculation formula, we get: Total sugar g / L = (0.156 + 0.005) × 10 / (1 × 0.269) × 100% = 5.98 g / L.

[0034] Table 4. Total Sugar Standard Curve Comparison

[0035] Table 5. Total Sugar Determination of Jasmine Kombucha Fermented Beverages

[0036] Sensory evaluation and determination of total polyphenol content: The experimental results show the correlation between the absorbance of the jasmine kombucha fermented beverage and the total polyphenol content, as shown in Table 6. The total polyphenol standard curve is shown below. Figure 6 As shown, the horizontal axis represents the total polyphenol concentration (mg / ml), and the vertical axis represents the absorbance (OD). 765nm The standard curve equation is y = 0.522x + 0.002, R0 2 =0.995; The absorbance values ​​of the jasmine kombucha fermented beverage diluted twice are shown in Table 7. From the experimental results, the absorbance values ​​of the jasmine kombucha fermented beverage measured three times were 0.119, 0.119, and 0.119, respectively. Therefore, the average value of the three titrations is 0.119. Substituting the average absorbance value measured in the experiment into the total phenol calculation formula, we get: .

[0037] Table 6. Total phenol standard curve comparison

[0038] Table 7. Determination of Total Phenolics in Jasmine Kombucha Fermented Beverages

[0039] Considering the pH value, total acid content, total sugar content, and total polyphenol content, the optimal formulation was found in Example 1, with the addition amounts of jasmine, kombucha, and white sugar. The measurement results are shown in Table 8.

[0040] Table 8. Measurement results of pH value, total acid content, total sugar content, and total polyphenol content in Example 1.

[0041] Orthogonal experiment verification: Based on the results of the single-factor experiments, an orthogonal experimental design was conducted using IBM SPSS Statistics 27 software. The results of the orthogonal experiments are shown in Table 9. The larger the range of the orthogonal experimental results, the greater the impact on the experimental results. Therefore, the range RA > RB > RC. Thus, the order of factors affecting the fermentation of jasmine kombucha beverage is: A. Jasmine flower addition amount > B. Kombucha addition amount > C. White sugar addition amount. According to the comparison of the average values ​​k1, k2, and k3 of each factor, the optimal process formula for jasmine kombucha fermentation beverage is A2B2C2, that is, the jasmine flower addition amount is 5 g / L, the kombucha addition amount is 5%, and the white sugar addition amount is 10%.

[0042] Table 9 L9 (3) 4 Orthogonal Experiment Results Table

[0043] An orthogonal experiment was conducted to evaluate the sensory characteristics of jasmine kombucha fermented beverage. Table 10 shows that the p-value for the amount of jasmine added was 0.025 < 0.05, the p-value for the amount of kombucha added was 0.043 < 0.05, and the p-value for the amount of white sugar added was 0.130 > 0.05. This indicates that the amounts of jasmine added and kombucha added have a significant impact on the sensory score of the jasmine kombucha fermented beverage, while the amount of white sugar added has no significant impact.

[0044] Table 10. Analysis of variance table showing the influence of different factors in the orthogonal experiment on the sensory scores of jasmine kombucha fermented beverage.

[0045] Note: *P < 0.05 indicates a significant difference; **P < 0.01 indicates a highly significant difference; "-" indicates no significant difference. Table 11 shows that the sensory evaluation of the superior combination A2B2C2 sample in the verification experiment was conducted from four aspects: color, aroma, taste, and texture. The sensory score was 90.8 points. Therefore, the optimal combination A2B2C2 was finally selected in the orthogonal experiment, which has 5 g / L jasmine flower, 5% kombucha, and 10% white sugar. This combination has the best overall product quality and good repeatability.

[0046] Table 11 Verification test results of the optimal combination in the orthogonal experiment

[0047] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for preparing a jasmine kombucha fermented beverage, characterized in that, Jasmine flowers are combined with white sugar to make jasmine syrup, and kombucha is inoculated into the jasmine syrup for fermentation to produce a jasmine kombucha fermented beverage.

2. The method for preparing jasmine kombucha fermented beverage according to claim 1, characterized in that, Includes the following steps: S1. Add jasmine flowers and white sugar to purified water, boil until the white sugar is completely dissolved, let it cool naturally to room temperature, and then filter it through a 100-mesh sterile filter to prepare jasmine tea sugar water. S2. Sterilize the filtered jasmine sugar water, inoculate it with kombucha culture under sterile conditions, seal it with sterile gauze, and ferment it at room temperature to obtain jasmine kombucha fermentation liquid. S3. Centrifuge the jasmine kombucha fermentation liquid, take the supernatant and sterilize it again at 80-85℃ for at least 30 minutes. After aseptic hot filling and cooling, store at 0-4℃ to obtain jasmine kombucha fermented beverage.

3. The method for preparing jasmine kombucha fermented beverage according to claim 2, characterized in that: In step S1, during the preparation of jasmine syrup, the amount of jasmine flowers added is 5 g / L, and the mass fraction of white sugar in the jasmine syrup is 10%.

4. The method for preparing jasmine kombucha fermented beverage according to claim 2, characterized in that: In step S2, the inoculation amount of kombucha in jasmine syrup is 5% by volume.

5. A jasmine kombucha fermented beverage prepared according to any one of claims 1 to 4.

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