Micro-bubble drinking type tea yoghourt and preparation method thereof

Abstract

The invention relates to a microbubble drinking type tea yoghourt and a preparation method thereof, and the preparation method comprises the following steps: mixing tea juice, lemon juice, sodium citrate, raw milk and sugar, sterilizing, inoculating with a complex microbial inoculant for fermentation, and demulsifying to obtain the microbubble drinking type tea yoghourt, the strains in the complex microbial inoculant comprise a combination of streptococcus salivarius subsp. Thermophilus, lactococcus lactis subsp. Diacetyl, plant lactobacillus and leuconostoc mesenteroides subsp. Mesenteroides. In the invention, a complex microbial inoculant of four specific microbial strains is adopted to ferment the dairy product, and the four strains are further found to have a synergistic effect, so that the tissue state, the taste, the smell and the overall fusion effect of the tea yoghourt product prepared by final fermentation are further improved; the microbubble tea yoghourt beverage with excellent taste and stable tissue state is prepared.

Description

Technical Field

[0001] This invention belongs to the field of dairy processing technology and relates to a microbubble-type tea yogurt and its preparation method. Background Technology

[0002] With the increasing demand from consumers for healthy and novel beverages, products that combine the flavors and nutrition of tea and yogurt are gradually gaining attention. Tea yogurt combines the functional components of tea (such as tea polyphenols and theanine) with the probiotics and protein nutrients of yogurt, showing considerable market potential. However, existing tea yogurt products have several shortcomings. On the one hand, flavor harmony is poor: the integration of tea extract and yogurt base is not ideal, easily resulting in a bitter tea taste, masking the yogurt flavor, or conflicting flavors, failing to create a harmonious and pleasant drinking experience. For example, tea yogurt prepared using traditional methods has an abrupt tea flavor, ruining the inherent smooth texture of yogurt. On the other hand, texture and stability are insufficient: during storage, problems such as water separation and abnormal viscosity changes are prone to occur (refer to the table data; water separation and viscosity fluctuations affect product texture under different temperatures and storage days). When stored at room temperature or under conventional refrigeration conditions, water separation increases with the number of days, and viscosity becomes unstable, leading to a coarser texture and layering, affecting consumer acceptance.

[0003] Existing tea yogurts are mostly in conventional liquid or semi-solid form, lacking a novel taste experience. Microbubbles, with their refreshing and stimulating sensation, are favored in the beverage market, but products combining microbubbles with tea yogurt are extremely rare. Consumers have a strong demand for diverse beverage flavors, which conventional tea yogurt can no longer satisfy. Traditional tea yogurt preparation methods result in low extraction rates of effective tea components and are prone to introducing undesirable flavors. During yogurt fermentation, the impact of tea components on probiotic activity is difficult to control, easily leading to abnormal fermentation and unstable product quality. Furthermore, there is currently no mature technological solution for precisely controlling microbubbles to ensure their uniform and stable dispersion within the tea yogurt system without compromising system stability, thus hindering the research and industrialization of microbubble tea yogurt.

[0004] Therefore, the development of a product that combines the refreshing sensation of microbubbles, the flavor and nutrition of tea yogurt, and stable storage has become an industry demand. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a microbubble-type tea yogurt and its preparation method.

[0006] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a microbubble-type tea yogurt, which is prepared by a method comprising the following steps: Tea juice, lemon juice, sodium citrate, raw milk and sugar are mixed and sterilized, then inoculated with compound microbial agents for fermentation and demulsification to obtain microbubble-type tea yogurt. The strains in the compound bacterial agent include a combination of Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum and Leuconostoc mesenteroides mesenteroides mesenteroides subsp. mesenteroides.

[0007] In this invention, a compound microbial agent comprising four specific microbial strains—Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum, and Leuconostoc mesenteroides enterica subsp. enterica—is used to ferment dairy products. The four strains can synergistically enhance each other, further improving the texture, flavor, and overall fusion of the final fermented tea yogurt product, thus preparing a microbubble tea yogurt beverage with excellent taste and stable texture.

[0008] Preferably, the ratio of viable counts of Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum and Leuconostoc mesenteroides ...

[0009] The "12~15" can be, for example, 12, 12.5, 13, 13.5, 14, 14.5, 15, etc. The "13~17" can be, for example, 13, 13.5, 14, 14.5, 15, 15.5, 16, 17, etc.; The "3~6" can be, for example, 3, 3.5, 4, 4.5, 5, 5.5, 6, etc.; The "10~14" can be, for example, 10, 11, 11.5, 12, 12.5, 13, 13.5, 14, etc.

[0010] Based on the synergistic relationship among the four specific microbial strains mentioned above, the effect is even better when the four are used in combination in the above specific ratio.

[0011] Preferably, the total viable bacteria concentration of the compound microbial agent is not less than 1×10⁻⁶. 6 CFU / mL or 1×10 6 CFU / g, for example, could be 1×10 6 CFU / mL (CFU / g), 2×10 6 CFU / mL (CFU / g), 5×10 6 CFU / mL (CFU / g), 8×10 6 CFU / mL (CFU / g), 1×10 7 CFU / mL (CFU / g), 5×10 7 CFU / mL (CFU / g), 1×108 CFU / mL (CFU / g), etc. Other specific point values ​​within this range can be selected, which will not be elaborated here.

[0012] Preferably, the raw materials for preparing the microbubble tea yogurt include, by weight, 0.3-5 parts tea juice, 0.1-2 parts lemon juice, 0.05-0.5 parts sodium citrate, 80-98 parts raw milk, 4-10 parts sugar, and 0.001-0.01 parts compound microbial agent.

[0013] The "0.3 to 5 portions" mentioned above can be, for example, 0.3 portions, 0.5 portions, 1 portion, 1.5 portions, 2 portions, 2.5 portions, 3 portions, 4 portions, 5 portions, etc. The aforementioned "0.1~2 portions" can be, for example, 0.1 portions, 0.3 portions, 0.5 portions, 1 portion, 1.2 portions, 1.5 portions, 2 portions, etc.; The aforementioned "0.05~0.5 parts" can be, for example, 0.05 parts, 0.1 parts, 0.25 parts, 0.3 parts, 0.4 parts, 0.5 parts, etc.; The aforementioned "80~98 portions" could be, for example, 80 portions, 82 portions, 85 portions, 88 portions, 90 portions, 95 portions, 98 portions, etc. The "4 to 10 portions" mentioned above can be, for example, 4 portions, 5 portions, 6 portions, 7 portions, 8 portions, 9 portions, 10 portions, etc. The "0.001~0.01 portions" mentioned above can be, for example, 0.001 portions, 0.002 portions, 0.005 portions, 0.008 portions, 0.01 portions, etc.

[0014] This invention employs a specific ratio of raw materials, in which the amount of tea concentrate added is precisely controlled and combined with lemon juice. This not only highlights the unique aroma of the tea but also uses the refreshing fruity aroma of lemon juice to neutralize any bitterness that the tea may bring. The aromas of tea, milk, and fruit complement each other, forming a harmonious and rich flavor profile with a unique taste experience. This overcomes the problem in existing technologies where tea yogurt either has an overly weak tea aroma or an overly strong tea aroma that results in a bitter taste.

[0015] Preferably, the raw materials for preparing the microbubble tea yogurt include, by weight, 2-4 parts tea juice, 0.1-1 parts lemon juice, 0.05-0.5 parts sodium citrate, 80-98 parts raw milk, 6-8 parts sugar, and 0.005-0.01 parts compound microbial agent.

[0016] Secondly, the present invention provides a method for preparing microbubble-type tea yogurt according to the first aspect, the preparation method specifically including the following steps: The first mixture is obtained by mixing tea juice, lemon juice, sodium citrate, raw milk and sugar. The sugar is added to heated raw milk and mixed well, and then combined with the first mixture. After homogenization, sterilization, fermentation with compound microbial agent, demulsification and low temperature treatment, microbubble tea yogurt is obtained. The strains in the compound bacterial agent include a combination of Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum and Leuconostoc mesenteroides mesenteroides mesenteroides subsp. mesenteroides.

[0017] Preferably, the heating temperature is 40~70℃, for example, it can be 40, 45, 50, 55, 60, 65, 70℃, etc. Other specific values ​​within this range can be selected, and will not be elaborated here; preferably, it is 45~55℃.

[0018] When raw milk is within the specific temperature range mentioned above, the casein micelle structure is stable, the whey protein undergoes only slight conformational changes without aggregation, and no visible precipitation is produced. The overall protein stability is high. When mixed with other raw materials in this process, local over-acidity and protein denaturation can be effectively avoided.

[0019] Preferably, the temperature of the first homogenization is 55~70℃ (e.g., 55, 58, 60, 65, 68, 70℃, etc.), and the pressure is 150~250 bar (e.g., 150 bar, 175 bar, 190 bar, 200 bar, 225 bar, 250 bar, etc.); more preferably, homogenization is carried out at a temperature of 60~65℃ and a homogenization pressure of 180~220 bar.

[0020] In the processing of tea yogurt products, the conditions of the first homogenization treatment within the above-mentioned specific range can effectively balance the degree of protein denaturation, particle size and component compatibility, ultimately forming a stable product with good water retention, delicate taste and no layering sedimentation. At the same time, it reduces energy consumption and component loss, making it the optimal choice that balances processing efficiency and product quality.

[0021] Preferably, the fermentation temperature is 20~45℃ (e.g., 20℃, 22℃, 25℃, 30℃, 35℃, 40℃, 45℃, etc.), and the time is 4~18 h (e.g., 4 h, 5 h, 6 h, 8 h, 10 h, 12 h, 15 h, 18 h, etc.); preferably, fermentation is carried out at 15~25℃ for 2.5~3 h. Preferably, the low-temperature treatment is performed at a temperature of 2-6°C (e.g., 2°C, 3°C, 4°C, 5°C, 6°C, etc.) for a time of 6-12 h (e.g., 6 h, 7 h, 8 h, 9 h, 10 h, 11 h, 12 h, etc.).

[0022] Preferably, the sterilization temperature is 90~97℃ (e.g., 90℃, 91℃, 92℃, 94℃, 95℃, 96℃, 97℃, etc.), and the time is 4~6 min (e.g., 4 min, 4.2 min, 4.5 min, 4.8 min, 5 min, 5.2 min, 5.5 min, 5.8 min, 6 min, etc.); preferably, sterilization is carried out at 93~95℃ for 4.5~5.5 min.

[0023] Specific sterilization conditions can promote whey protein denaturation and binding with casein, inactivate harmful enzymes, and stabilize the interaction between tea components and proteins, laying the foundation for the textural stability of tea yogurt. This ensures that whey protein is fully denatured to form a dense gel network while preventing excessive protein aggregation and oxidation of tea components. Ultimately, this results in a product with a stable texture that is moderately thick, has strong water-holding capacity, is free of grains, and resists layering, while also considering flavor and processing efficiency.

[0024] Preferably, after demulsification, a second homogenization and / or secondary fermentation treatment is performed.

[0025] The tea yogurt beverage after the second homogenization process has better fluidity and a more stable texture. Secondary fermentation can also regulate fluidity and viscosity by affecting the protein network structure and water distribution, and the gas produced by lactic acid bacteria metabolism can make up for the gas and microbubble state lost during the second homogenization process, further improving the texture stability of the microbubble tea yogurt.

[0026] Preferably, the temperature of the second homogenization is 15~35℃ (e.g., 15℃, 18℃, 20℃, 22℃, 25℃, 28℃, 30℃, 32℃, 35℃, etc.), and the homogenization pressure is 0 bar; preferably, the homogenization is carried out under the conditions of temperature 20~25℃ and pressure 0 Bar.

[0027] The second homogenization process can further regulate the texture and microbubbles of the product, balancing fluidity and richness of taste. Specific technical parameter ranges can make the product have moderate viscosity, fine texture and evenly distributed microbubbles, which not only meets the convenience of drinking, but also enhances the refreshingness through the feeling of bubbles. It is highly matched with the flavor characteristics of tea components and is a key process parameter to ensure the quality of drinkable tea yogurt.

[0028] Preferably, the temperature of the secondary fermentation treatment is 15~30℃ (e.g., 15℃, 18℃, 20℃, 22℃, 25℃, 28℃, 30℃, etc.), and the time is 2~4 h (e.g., 2 h, 2.2 h, 2.5 h, 2.8 h, 3 h, 3.5 h, 4 h, etc.).

[0029] Compared with the prior art, the present invention has the following beneficial effects: In this invention, a compound microbial agent comprising four specific microbial strains—Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum, and Leuconostoc mesenteroides enterica subsp. enterica—is used to ferment dairy products. These four strains synergistically enhance the texture, flavor, and overall fusion of the resulting tea yogurt product, producing a microbubble tea yogurt beverage with excellent taste and stable texture. Furthermore, the specific ingredient ratios and coordinated use of these components highlight the unique aroma of tea while using the refreshing fruity aroma of lemon juice to neutralize any bitterness from the tea. This allows the tea, milk, and fruit aromas to complement each other, creating a harmonious and rich flavor profile and a unique taste experience. Detailed Implementation

[0030] To further illustrate the technical means and effects of the present invention, the following describes the technical solution of the present invention in conjunction with preferred embodiments of the present invention. However, the present invention is not limited to the scope of the embodiments.

[0031] Unless otherwise specified, the raw materials used in the following embodiments are all commercially available.

[0032] The sources of the raw materials in the following embodiments are: Raw milk refers to normal milk squeezed from the udder of a healthy dairy cow that meets relevant national requirements, without any alteration to its composition. It does not include colostrum within seven days after calving, milk produced during antibiotic use and withdrawal periods, or spoiled milk. The tea juice was a Longjing tea concentrate product purchased from Hangzhou Mingbao Biotechnology Co., Ltd.; the lemon juice was a lemon concentrate product purchased from Fujian Luquan Food Co., Ltd.

[0033] The following information pertains to the strains: ① Classification and naming of strain CT-01 Streptococcus thermophilus The depositary institution is Guangdong Provincial Center for Microbial Culture Collection, the deposit date is March 29, 2024, the accession number is GDMCC No: 64473, and the address is: 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou. ② The strain FLP-215 is classified as Lactobacillus plantarum. Lactobacillus plantarum The depositary institution is the China General Microbiological Culture Collection Center (CGMCC), the deposit date is September 4, 2023, the accession number is CGMCC No. 28337, and the address is No. 3, No. 1, Beichen West Road, Chaoyang District, Beijing. ③ The MA195 strain is the Lactococcus lactis diacetyl subsp. MA195 strain purchased from Pulse Biotechnology Co., Ltd., France; ④ ATCC 8293 strain is Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293 strain.

[0034] The following commercially available product 1 is a tea yogurt product sourced from Langgege Company; commercially available product 2 is a tea yogurt product sourced from Shengmu Company.

[0035] The preparation method of the compound microbial agent involved below is as follows: after activating the strain, it is inoculated into the culture medium and cultured to obtain a culture solution; the culture solution is centrifuged, and the bacterial suspension is obtained by resuspending the bacterial suspension, or a protectant is added and freeze-dried to obtain a freeze-dried microbial powder product.

[0036] Example 1 This embodiment provides a microbubble-type tea yogurt, prepared by the following method: Preparation ingredients: 2% (w / w) tea juice, 6% (w / w) white sugar, 0.2% (w / w) sodium citrate, 0.5% (w / w) lemon juice, 0.005% (w / w) compound microbial agent, and the remainder is raw milk.

[0037] (1) Mix tea juice, lemon juice and sodium citrate in proportion and stir for 10 min until sodium citrate is completely dissolved and homogeneous to obtain a mixture; (2) Heat the raw milk to 50°C, add white sugar, stir for 10 min, slowly add the mixture obtained in step (1), and stir for 10 min; (3) Homogenize the liquid obtained in step (2) at a temperature of 65°C and a pressure of 200 bar. (4) Sterilize the liquid obtained in step (3) at 95°C for 5 min; (5) The compound microbial agent (containing Streptococcus salivarius thermophilus subsp. CT-01, Lactococcus lactis subsp. diacetyl MA195, Lactobacillus plantarum FLP-215, and Leuconostoc mesenteroides subsp. enterica ATCC 8293 with a live bacteria ratio of 13:15:4:12, and a total live bacteria concentration of 1×10⁻⁶) was prepared. 6 CFU / g) was inoculated into the sterilized mixture obtained in step (4), and after intermittent forward and reverse stirring for 10 min, it was fermented in a sealed container at 40℃ for 6 h. (6) After the fermented milk in step (5) is demulsified, it is homogenized twice. The homogenization temperature is 20°C and the homogenization pressure is 0 bar. (7) The yogurt liquid obtained in step (6) is then bottled. (8) The product obtained in step (7) is fermented again at 20°C for 3 hours; (9) The product obtained in step (8) is refrigerated at 4°C for 10 h to obtain the microbubble tea yogurt.

[0038] Example 2 This embodiment provides a microbubble-type tea yogurt, prepared by the following method: Ingredients: 2% (w / w) tea juice, 6% (w / w) white sugar, 0.05% (w / w) sodium citrate, 1% (w / w) lemon juice, 0.006% (w / w) compound microbial agent, and the remainder is raw milk.

[0039] (1) Mix tea juice, lemon juice and sodium citrate in proportion and stir for 10 min until sodium citrate is completely dissolved and homogeneous to obtain a mixture; (2) Heat the raw milk to 50°C, add white sugar, stir for 10 min, slowly add the mixture obtained in step (1), and stir for 10 min; (3) Homogenize the liquid obtained in step (2) at a temperature of 65°C and a pressure of 200 bar. (4) Sterilize the liquid obtained in step (3) at 95°C for 5 min; (5) The compound microbial agent (containing Streptococcus salivarius thermophilus subsp. CT-01, Lactococcus lactis subsp. MA195, Lactobacillus plantarum FLP-215, and Leuconostoc mesenteroides subsp. ATCC8293 with a live bacteria ratio of 12:13:6:14, and a total live bacteria concentration of 1×10⁻⁶) was prepared. 6 CFU / mL) was inoculated into the sterilized mixture obtained in step (4), and after intermittent forward and reverse stirring for 10 min, it was fermented in a sealed container at 30℃ for 12 h. (6) After the fermented milk in step (5) is demulsified, it is homogenized twice. The homogenization temperature is 20°C and the homogenization pressure is 0 bar. (7) The yogurt liquid obtained in step (6) is then bottled. (8) Ferment the product obtained in step (7) at 25°C for 2.5 hours; (9) The product obtained in step (8) is refrigerated at 4°C for 12 h to obtain the microbubble tea yogurt.

[0040] Example 3 This embodiment provides a microbubble-type tea yogurt, prepared by the following method: Ingredients: 4% (w / w) tea juice, 8% (w / w) white sugar, 0.5% (w / w) sodium citrate, 0.1% (w / w) lemon juice, 0.01% (w / w) compound microbial agent, and the remainder is raw milk.

[0041] (1) Mix tea juice, lemon juice and sodium citrate in proportion and stir for 10 min until sodium citrate is completely dissolved and homogeneous to obtain a mixture; (2) Heat the raw milk to 50°C, add white sugar, stir for 10 min, slowly add the mixture obtained in step (1), and stir for 10 min; (3) Homogenize the liquid obtained in step (2) at a temperature of 65°C and a pressure of 200 bar. (4) Sterilize the liquid obtained in step (3) at 95°C for 5 min; (5) The compound bacterial agent (containing Streptococcus salivarius thermophilus subsp. CT-01, Lactococcus lactis subsp. MA195, Lactobacillus plantarum FLP-215, and Leuconostoc mesenteroides subsp. ATCC8293 with a live bacteria ratio of 15:17:3:10, and a total live bacteria concentration of 1×10⁻⁶) was prepared. 6 CFU / g) was inoculated into the sterilized mixture obtained in step (4), and after intermittent forward and reverse stirring for 10 min, it was fermented in a sealed container at 37℃ for 9 h. (6) After the fermented milk in step (5) is demulsified, it is homogenized twice. The homogenization temperature is 20°C and the homogenization pressure is 0 bar. (7) The yogurt liquid obtained in step (6) is then bottled. (8) The product obtained in step (7) is fermented again at 15°C for 4 hours; (9) The product obtained in step (8) is refrigerated at 4°C for 8 hours to obtain the microbubble tea yogurt.

[0042] Example 4 This embodiment provides a microbubble tea yogurt, which uses the liquid system after demulsification in step (6) of embodiment 1. The only difference between its preparation method and that of embodiment 1 is that it does not perform secondary homogenization. After demulsification, it directly proceeds to subsequent steps (7) to (9). The remaining processes and related technical parameters are the same as those in embodiment 1.

[0043] Example 5 This embodiment provides a microbubble tea yogurt, which uses the liquid system after demulsification in step (6) of embodiment 1. The only difference between its preparation method and that of embodiment 1 is that the secondary homogenization pressure is adjusted to 200 bar. All other processes and related technical parameters are the same as those in embodiment 1.

[0044] Example 6 This embodiment provides a microbubble tea yogurt, which is the product after canning in step (7) of embodiment 1. The only difference between its preparation method and that of embodiment 1 is that the secondary fermentation in step (8) is not carried out, and the low-temperature treatment in step (9) is carried out directly. The other processes and related technical parameters are the same as those in embodiment 1.

[0045] Comparative Example 1 This comparative example provides a microbubble tea yogurt, which differs from Example 1 only in that lemon juice is not added to the raw materials. The relevant preparation process and related technical parameters are the same as those in Example 1.

[0046] Comparative Example 2 This comparative example provides a microbubble tea yogurt, which differs from Example 1 only in that sodium citrate is not added to the raw materials. The relevant preparation process and related technical parameters are the same as those in Example 1.

[0047] Comparative Example 3 This comparative example provides a microbubble-type tea yogurt, using the liquid system sterilized in step (4) of Example 1. The only difference between this example and Example 1 is that the compound bacterial agent does not contain Streptococcus salivarius thermophilus subsp. CT-01 strain, and the reduced amount is allocated to three strains according to the ratio of viable bacteria: Lactococcus lactis subsp. diacetyl MA195 strain, Lactobacillus plantarum FLP-215 strain, and Leuconostoc mesenteroides subsp. enterica ATCC 8293 strain. The remaining process flow and related technical parameters are the same as in Example 1.

[0048] Comparative Example 4 This comparative example provides a microbubble-type tea yogurt, using the sterilized liquid system from step (4) of Example 1. The only difference between this example and Example 1 is that the compound microbial agent does not contain Lactococcus diacetyl subsp. MA195 strain, and the reduced amount is allocated to three strains according to the ratio of live bacteria: Streptococcus salivarius thermophilus subsp. CT-01 strain, Lactobacillus plantarum FLP-215 strain, and Leuconostoc mesenteroides enterica subsp. ATCC 8293 strain. The remaining process flow and related technical parameters are the same as in Example 1.

[0049] Comparative Example 5 This comparative example provides a microbubble-type tea yogurt, using the sterilized liquid system from step (4) of Example 1. The only difference between this example and Example 1 is that the compound bacterial agent does not contain Leuconostoc mesenteroides ATCC 8293 strain, and the reduced amount is distributed to three strains according to the ratio of viable bacteria: Streptococcus salivarius thermophilus subsp. CT-01 strain, Lactobacillus plantarum FLP-215 strain, and Lactococcus lactis diacetyl subsp. MA195 strain. The remaining process flow and related technical parameters are the same as in Example 1.

[0050] Comparative Example 6 This comparative example provides a microbubble-type tea yogurt, using the sterilized liquid system from step (4) of Example 1. The only difference between this example and Example 1 is that the compound microbial agent does not contain the *Lactobacillus plantarum* FLP-215 strain, and the reduced amount is distributed to three strains according to the ratio of live bacteria: *Streptococcus salivarius* subsp. *thermophilus* CT-01 strain, *Leuconostoc mesenteroides* subsp. *enteroides* ATCC 8293 strain, and *Lactococcus lactis* subsp. *diacetyl* MA195 strain. The remaining process flow and related technical parameters are the same as in Example 1.

[0051] Test Example 1 Forty-five dairy researchers were selected to conduct sensory evaluations of microbubble tea yogurt.

[0052] Each evaluation was conducted individually by each evaluator, without contact or communication between them. Evaluators rinsed their mouths with water between evaluations of each sample. Specific evaluation criteria and scoring standards are shown in Table 1.

[0053] Table 1 The specific evaluation results of the microbubble tea yogurt are shown in Table 2: Table 2 The sensory evaluation results in the table above show that the microbubble tea yogurt prepared by the present invention using a special process is superior to commercially available tea yogurt in terms of texture, flavor, and overall blending.

[0054] (1) Comparing Example 1 with Examples 4-5, it can be seen that the use of secondary homogenization and specific process parameters can improve the texture and fluidity of microbubble tea yogurt.

[0055] (2) Comparing Example 1 and Example 6, it can be seen that when secondary fermentation was not carried out in Example 6, the stability of the texture of the final microbubble tea yogurt decreased and the sensory evaluation results were worse than those of the Example.

[0056] (3) Comparing Example 1 with Comparative Examples 1-2, it can be seen that when lemon juice or sodium citrate is not added to the preparation system, the flavor of the related tea yogurt products prepared is not as good as that of Example 1. This indicates that the addition of lemon juice or sodium citrate can further enhance the flavor of tea yogurt and prepare tea yogurt drinks with better sensory experience.

[0057] (4) Comparing Example 1 with Comparative Examples 1-4, it can be seen that in this invention, four strains of bacteria are combined and used in combination: Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum and Leuconostoc mesenteroides mesenteroides subsp. enterica. The four strains can synergistically enhance the fermentation effect on dairy products and prepare tea yogurt products with better flavor, excellent taste, overall integration and stable texture.

[0058] In summary, through the evaluation of the sensory characteristics of the microbubble tea yogurt, the microbubble tea yogurt prepared by this invention was recognized by the tasters, showing significant improvements in flavor, a more delicate and smooth texture, better fluidity, and better suitability to Chinese tastes. The use of lemon juice and sodium citrate further enhances the flavor of the microbubble tea yogurt, while secondary homogenization and secondary fermentation improve its texture and fluidity. The addition of *Streptococcus thermophilus* subsp. *salicylic acid bacteria*, *Lactococcus diacetyl* subsp. *plantatus*, and *Leuconostoc mesenteroides* subsp. *mesenteroides* further improves the overall performance of the microbubble tea yogurt.

[0059] Test Example 2 The carbon dioxide gas capacity of the tea yogurt samples prepared in Examples 1, 4-6 and Comparative Examples 1-6 was tested according to the reduced pressure gas method in GB / T 10792 "Carbonated Beverages (Soft Drinks)". The test temperature was 10℃, and the final form was measured. The results are shown in Table 3.

[0060] Table 3 The results in Table 3, showing the carbon dioxide volume and final morphology, demonstrate that the microbubble-type tea yogurt of this invention exhibits outstanding efficiency and stability in microbubble formation, successfully achieving the characteristics of tiny, continuous, and uniform pores. This not only provides the physical basis for the refreshing taste of microbubbles but also confirms the product's significant advantages in bubble formation efficiency, distribution uniformity, and stability, further distinguishing it from the shortcomings of existing products that are either dense and bubble-free or have chaotic and unstable bubbles. Specifically, Example 1 shows significantly better results than Examples 4-6, Comparative Examples 1-6, and two similar commercially available products, indicating that the specific fermentation process, related raw material components, and technical parameters used in this invention all influence the specific taste of the final microbubble-type tea yogurt to varying degrees.

[0061] In summary, the microbubble tea yogurt produced by this invention has significant improvements in three aspects: texture, flavor, and overall blending. The microbubble tea yogurt is delicate and smooth, with good fluidity, and is rich in milk, tea, and refreshing fruit flavors. With the unique refreshing sensation and layered flavor of microbubbles, it precisely meets the pursuit of contemporary consumers, opening up a new market track for the tea yogurt category and possessing all-round competitiveness from function to experience.

[0062] The applicant declares that the technical solution of this invention is illustrated by the above embodiments, but this invention is not limited to the above embodiments, that is, it does not mean that this invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the products of this invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

[0063] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0064] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.

Claims

1. A microbubble-flavored tea yogurt, characterized in that, The microbubble-type tea yogurt is prepared by a method including the following steps: Tea juice, lemon juice, sodium citrate, raw milk and sugar are mixed and sterilized, then inoculated with compound microbial agents for fermentation and demulsification to obtain microbubble-type tea yogurt. The strains in the compound bacterial agent include a combination of Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum and Leuconostoc mesenteroides mesenteroides mesenteroides subsp. mesenteroides.

2. The microbubble-type tea yogurt according to claim 1, characterized in that, The ratio of viable counts of Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum and Leuconostoc mesenteroides ...

3. The microbubble-type tea yogurt according to claim 1, characterized in that, The total viable bacteria concentration of the compound microbial agent is not less than 1×10⁻⁶. 6 CFU / mL or 1×10 6 CFU / g.

4. The microbubble-type tea yogurt according to claim 1, characterized in that, The raw materials for preparing the microbubble-type tea yogurt include, by weight, 0.3-5 parts tea juice, 0.1-2 parts lemon juice, 0.05-0.5 parts sodium citrate, 80-98 parts raw milk, 4-10 parts sugar, and 0.001-0.01 parts compound microbial agent.

5. The microbubble-type tea yogurt according to claim 4, characterized in that, The raw materials for preparing the microbubble-type tea yogurt include, by weight, 2-4 parts tea juice, 0.1-1 parts lemon juice, 0.05-0.5 parts sodium citrate, 80-98 parts raw milk, 6-8 parts sugar, and 0.005-0.01 parts compound microbial agent.

6. A method for preparing a microbubble-type tea yogurt according to any one of claims 1 to 5, characterized in that, The preparation method specifically includes the following steps: The first mixture is obtained by mixing tea juice, lemon juice, sodium citrate, raw milk and sugar. The sugar is added to heated raw milk and mixed well, and then combined with the first mixture. After homogenization, sterilization, fermentation with compound microbial agent, demulsification and low temperature treatment, microbubble tea yogurt is obtained. The strains in the compound bacterial agent include a combination of Streptococcus salivarius thermophilus subsp., Lactococcus lactis diacetyl subsp., Lactobacillus plantarum and Leuconostoc mesenteroides mesenteroides mesenteroides subsp. mesenteroides.

7. The preparation method according to claim 6, characterized in that, The heating temperature is 40~70℃; Preferably, the temperature of the first homogenizer is 55~70°C and the pressure is 150~250 bar.

8. The preparation method according to claim 6, characterized in that, The fermentation temperature is 20~45℃, and the time is 4~18 h; preferably, fermentation is carried out at 15~25℃ for 2.5~3 h. Preferably, the low-temperature treatment is performed at a temperature of 2-6°C for 6-12 hours.

9. The preparation method according to claim 6, characterized in that, After demulsification, a second homogenization and / or secondary fermentation process is performed.

10. The preparation method according to claim 9, characterized in that, The temperature for the second homogenization is 15~35℃; Preferably, the temperature of the secondary fermentation treatment is 15~30℃ and the time is 2~4 h.

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