Highly active probiotic nutritional tablet and method of making same

Abstract

The application belongs to the field of functional food preparation, and provides a high-viability probiotic nutritional tablet and a preparation method thereof. The application performs low-water-activity surface protection on a food processing strain preparation freeze-dried powder by a prebiotic vitrification matrix, and forms a low-humidity tabletting system with food-grade starch, food-grade erythritol and food additive silicon dioxide. The tablet is obtained through low-temperature and low-humidity mixing, low-strength tabletting and low-oxygen sealing, and the high-viability, post-tabletting viability maintenance rate, tablet hardness, low friability and storage stability are balanced, the problem that the tablet structure integrity and the viability maintenance rate, the processing fluidity and the storage stability are difficult to unify is solved, and the application is suitable for probiotic nutritional supplementation and normal-temperature sealed storage scenarios.

Description

Technical Field

[0001] This invention relates to the field of functional food preparations, specifically to a high-live-bacteria probiotic nutritional tablet and its preparation method. Background Technology

[0002] Probiotic tablets, as a functional food form that can be consumed directly, is convenient to carry, and is available in measured doses, typically need to maintain high levels of live bacteria during room temperature circulation, shelf storage, and daily consumption. They also require sufficient tablet hardness, low friability, suitable disintegration time, and stable sensory properties. Compared to capsules and powders, tablets are affected by mechanical pressure, localized frictional heating, and the moisture content of the powder during compression. Furthermore, freeze-dried live bacteria powders are more sensitive to moisture, oxygen, temperature, and compressive stress. Therefore, product design must meet the requirements of flowability, formability, and batch-to-batch consistency in industrial tableting, while also preventing live bacteria attenuation caused by moisture absorption of tablet excipients, over-compaction, or insufficient packaging barriers. For high-live-bacteria probiotic tablets intended for room temperature sealed storage, establishing a synergistic control system between low water activity protection, prebiotic function carrying capacity, dry mixing and tableting, and low-oxygen sealing is crucial for improving product stability and production repeatability.

[0003] Current probiotic tablet technologies typically reduce processing damage by selecting tableting excipients, controlling granulation methods, or lowering tableting pressure. However, these different approaches still present challenges due to their interdependencies. For example, Chinese patent CN110960560B discloses a tablet with high probiotic activity, its preparation method, and its application. Its abstract describes achieving higher mechanical strength and reducing live bacteria loss at lower pressures through appropriate excipients and granulation steps. However, this approach still highlights a close correlation between probiotic compression, hygroscopic environment, and the live bacteria content during shelf life. In actual tablet development, increasing hardness often requires enhancing particle compaction or improving binding strength, which may increase pressure damage to lyophilized bacteria. Improving flowability often relies on dry powder flow aids, but this may alter particle contact, hygroscopic pathways, and disintegration behavior. Simply reducing moisture or increasing barrier properties may narrow the tableting mixture's forming window. Therefore, a high-live-bacteria probiotic nutrient tablet solution that can achieve a balance between low water activity protected particles, tableting dry matrix, tableting conditions, and sealed packaging is still needed. Summary of the Invention

[0004] The purpose of this invention is to provide a high-live-bacteria probiotic nutritional tablet and its preparation method, which solves the problem that it is difficult to simultaneously achieve tablet structural integrity and live bacteria retention rate, processing flowability and live bacteria storage stability in current high-live-bacteria probiotic tablets.

[0005] This invention provides low water activity surface protection for freeze-dried microbial preparations for food processing using a prebiotic vitrified matrix. It also incorporates food-grade starch, food-grade erythritol, and food additive silica to form a low-moisture tableting system. This system matches the particle support and flow aid required for tableting with low-moisture protection within the same system, thereby reducing both compaction damage and moisture absorption inactivation side effects.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A high-live-bacteria probiotic nutritional tablet, based on a total mass of 100wt% of the finished high-live-bacteria probiotic nutritional tablet, is composed of the following components, and the sum of the contents of each component is 100wt%: a. Prebiotic vitrified matrix protects live bacteria particles 30–70 wt%; b. Food-grade starch 10–40 wt%; c. Food-grade erythritol 5–30 wt%; d. Food additive silicon dioxide 0.2–1.0 wt%; The prebiotic vitrified matrix-protected live bacteria particles include freeze-dried microbial preparations for food processing and a prebiotic vitrified matrix. The mass ratio of the prebiotic vitrified matrix to the freeze-dried powder of the food processing microbial culture preparation is 2:1 to 20:1. The prebiotic vitrified matrix protects the live bacteria particles with a D50 of 80–250 μm and a water activity (aw) of 0.05–0.20. The high-live-bacteria probiotic nutritional tablet has a water activity (aw) of 0.05–0.25, and the number of live bacteria per tablet at the time of manufacture is 1 × 10⁻⁶. 9 –1×10 11 CFU.

[0007] Furthermore, the freeze-dried microbial preparation for food processing contains one or more live bacteria selected from Lactobacillus plantarum, Lactobacillus rhamnosus, Bifidobacterium animalis subsp. lactis, and Lactobacillus acidophilus. The prebiotic vitrified matrix comprises inulin and food-grade resistant dextrin, or comprises inulin, food-grade resistant dextrin and D-trehalose dihydrate, wherein the D-trehalose dihydrate accounts for 1–20 wt% of the total mass of the prebiotic vitrified matrix; the prebiotic vitrified matrix is ​​distributed on the surface of the freeze-dried powder of the food processing microbial preparation, and simultaneously serves as the prebiotic and dietary fiber components in the high-live-bacteria probiotic nutritional tablets.

[0008] Furthermore, the prebiotic vitrified matrix-protected live bacteria particles are prepared through the following steps: A1. Provide freeze-dried microbial preparations for food processing; A2. Provides a prebiotic vitrified matrix powder, wherein the prebiotic vitrified matrix powder is composed of 60–95 wt% inulin and 5–40 wt% food-grade resistant dextrin, and the sum of the contents of inulin and food-grade resistant dextrin is 100 wt%, all percentages are based on the total mass of the prebiotic vitrified matrix powder, and the prebiotic vitrified matrix powder is obtained by mixing inulin and food-grade resistant dextrin and pre-drying; A3. Mix 100 parts by weight of the freeze-dried powder of the microbial inoculum preparation for food processing with 200–2000 parts by weight of the prebiotic vitrified matrix powder, or mix 100 parts by weight of the freeze-dried powder of the microbial inoculum preparation for food processing with 200–2000 parts by weight of the prebiotic vitrified matrix powder containing the prebiotic vitrified matrix powder and D-trehalose dihydrate, and mix for 5–20 min at a temperature of 15–25°C, a relative humidity of 5–25%, and an absolute pressure of 0.09–0.11 MPa to obtain a low-humidity premix. A4. Spray 0.5–8.0 parts by weight of deionized water for food production into the low-moisture premix, and granulate for 5–25 minutes at a temperature of 20–32°C, a relative humidity of 5–25%, and an absolute pressure of 0.09–0.11 MPa to obtain wet granules. A5. The wet particles are dried at a temperature of 25–35℃, an absolute pressure of 0.09–0.11 MPa, and a drying time of 0.5–3.0 h, so that the water activity aw of the particles reaches 0.05–0.20; A6. Granulate the particles obtained in step A5 to obtain particles with a D50 of 80–250 μm, a prebiotic vitrification matrix surface coverage of 60–95%, and a viable bacterial count of 1 × 10⁻⁶ before tableting. 9 –1×10 11 CFU / g of prebiotic vitrified matrix protects live bacteria particles; The prebiotic vitrified matrix in the prebiotic vitrified matrix protects the live bacteria particles and serves as a prebiotic and dietary fiber, as well as a low water activity protection function on the surface of the freeze-dried powder of the microbial preparation for food processing.

[0009] Furthermore, the viable count of the freeze-dried microbial preparation for food processing described in step A1 is 1 × 10⁻⁶. 10 –5×10 11 The prebiotic vitrified matrix powder in step A2 has a moisture content of 0.3–4.0 wt%, a water activity of 0.03–0.18, and a D50 of 20–180 μm.

[0010] Furthermore, the prebiotic vitrified matrix powder mentioned in step A2 is prepared through the following steps: A21. Mix 60–95 parts by weight of inulin with 5–40 parts by weight of food-grade resistant dextrin for 8–25 min to obtain a prebiotic mixed powder; A22. The prebiotic mixed powder is pre-dried at a temperature of 30–45℃ and an absolute pressure of 0.09–0.11MPa for 1–6 hours. When the moisture content of the prebiotic mixed powder is 0.3–4.0wt% and the water activity aw is 0.03–0.18, the prebiotic vitrified matrix powder is obtained, and the D50 of the obtained prebiotic vitrified matrix powder is 20–180μm. A23. The prebiotic vitrified matrix powder is mixed with the freeze-dried powder of the microbial inoculum preparation for food processing in step A3, and distributed on the surface of the freeze-dried powder of the microbial inoculum preparation for food processing during the granulation process in step A4.

[0011] Furthermore, the food-grade starch, the food-grade erythritol, and the food additive silica form a low-moisture tableting dry matrix, which is prepared through the following steps: C1. Mix food-grade starch and food-grade erythritol according to their corresponding mass ratios in the finished high-live-bacteria probiotic nutritional tablets for 8–25 min; C2. Add food additive silicon dioxide to the mixture from step C1 according to the corresponding mass fraction of food additive silicon dioxide in the finished product of the high live bacteria probiotic nutritional tablets, and continue mixing for 3–12 min to obtain a low-moisture compressed dry matrix. C3. The mixing process is carried out at a temperature of 15–25°C, a relative humidity of 5–25%, and an absolute pressure of 0.09–0.11 MPa; C4. The moisture content of the dry matrix of the low-moisture tablet is 0.3–5.0 wt%, and the water activity (aw) is 0.03–0.20.

[0012] Furthermore, the strains in the freeze-dried powder of the food processing microbial preparation are all strains that can be used in food as announced by the national health authorities; when the freeze-dried powder of the food processing microbial preparation contains Bifidobacterium, the Bifidobacterium is Bifidobacterium animalis subsp. lactis; the prebiotic vitrification matrix also includes 1–20 wt% D-trehalose dihydrate, the percentage of D-trehalose dihydrate is based on the total mass of the prebiotic vitrification matrix, and the sum of the mass of the prebiotic vitrification matrix powder and the mass of D-trehalose dihydrate is the total mass of the prebiotic vitrification matrix containing D-trehalose dihydrate.

[0013] Furthermore, the tablet hardness of the high-live-bacteria probiotic nutritional tablets is 30–120 N, the friability is 0.05–1.00 wt%, the disintegration time is 3–25 min, the moisture content is 0.5–3.5 wt%, and the water activity (aw) is 0.05–0.25; the viable bacteria retention rate of the high-live-bacteria probiotic nutritional tablets after compression is 80–98%, and the viable bacteria retention rate after storage at a temperature of 25–30℃ and under sealed and light-protected conditions for 3–12 months is 40–95%.

[0014] As a concept of this invention, the present invention employs a design combining a prebiotic vitrified matrix to protect live bacteria particles with a low-moisture compressed dry matrix, primarily aimed at achieving a synergistic balance between tablet structural integrity and live bacteria retention. In existing technologies, to improve tablet hardness and reduce brittleness, it is typically necessary to enhance powder compaction and interparticle bonding; however, compressive stress and localized frictional heating can easily weaken the activity of freeze-dried bacteria. To maintain the live bacteria count, there is a tendency to reduce compression strength and increase the proportion of protective excipients, which may lead to loose tablet structure, disintegration, and fluctuations in flowability. This invention utilizes inulin and food-grade resistant dextrin to form a low-water-activity surface protection, while simultaneously employing food-grade starch, food-grade erythritol, and food additive silica to construct a dry matrix with matched compressibility and flowability. This allows live bacteria protection, powder flow, and tableting to mutually correct each other within the same system, thereby balancing tablet forming quality and live bacteria stability.

[0015] This invention also discloses a method for preparing high-live-bacteria probiotic nutritional tablets, comprising the following steps: S1. Provides pre-prepared prebiotic vitrified matrix to protect live bacteria particles and a low-moisture tableting dry matrix formed from food-grade starch, food-grade erythritol and food additive silica; S2. Mix the prebiotic vitrified matrix protected live bacteria particles and the low-humidity tableting dry matrix at a temperature of 15–25°C and a relative humidity of 5–25% for 8–25 minutes to obtain a low-humidity tableting mixture; S3. The low-moisture tableting mixture is compressed into tablets under a tableting force of 3–12 kN and a tableting temperature of 20–35°C to obtain tablets; S4. The tablets are sealed in a food-grade nitrogen atmosphere with an oxygen content of 0.1–5.0 vol% to obtain the high-live-bacteria probiotic nutritional tablets.

[0016] Furthermore, the moisture content of the low-moisture tableting mixture obtained in step S2 is 0.5–3.5 wt%, the water activity aw is 0.05–0.23, and the bulk density is 0.30–0.90 g / mL; the single tablet weight of the tablets mentioned in step S3 is 0.6–1.8 g, and the water activity aw of the tablets after compression is 0.05–0.25.

[0017] Furthermore, in step S4, the water vapor permeation rate of the sealed packaging is 0.01–1.00 g / (m²). 2 •d) The relative humidity inside the packaging is 1–20%.

[0018] Furthermore, the material contact temperature is controlled at 15–35°C throughout the entire preparation process, and the cumulative time the material is exposed to an environment with a relative humidity higher than 25% does not exceed 20 minutes.

[0019] Furthermore, the inter-batch coefficient of variation (COP) for D50 of the three batches of prebiotic vitrified matrix-protected live bacteria granules provided in step S1 was 2–15%, and the inter-batch COP for water activity (aw) of the three batches was 1–12%; the inter-batch COP for the high live bacteria retention rate of the three batches of high live bacteria probiotic nutritional tablets prepared using the prebiotic vitrified matrix-protected live bacteria granules provided in step S1 was 3–20%.

[0020] Furthermore, the prebiotic vitrified matrix protected live bacteria granules use freeze-dried powder of food processing microbial inoculum preparation as the source of live bacteria and prebiotic vitrified matrix or prebiotic vitrified matrix powder as the surface protective material. 100 parts by weight of freeze-dried powder of food processing microbial inoculum preparation is mixed with 200-2000 parts by weight of prebiotic vitrified matrix or prebiotic vitrified matrix powder at a temperature of 15-25℃, relative humidity of 5-25%, and absolute pressure of 0.09-0.11MPa for 5-20 minutes, followed by water spray granulation, low-temperature drying, and granulation to obtain the granules, which are then used as the live bacteria input material in the subsequent low-humidity tableting mixture.

[0021] Furthermore, when evaluating the glass transition state of the pre-dried prebiotic vitrified matrix powder, the test sample was a prebiotic vitrified matrix powder with a moisture content of 0.3–4.0 wt% and a water activity aw of 0.03–0.18. The glass transition temperature Tg was determined by differential scanning calorimetry, and the sample number, moisture content, aw, Tg initiation temperature, Tg midpoint temperature, and Tg endpoint temperature were recorded. The correspondence between the obtained Tg data and the storage temperature of 25–30℃ was used as the quality control standard for the prebiotic vitrified matrix powder to enter the granulation step.

[0022] Furthermore, when determining the surface coverage of the prebiotic vitrified matrix protected live bacteria granules after granulation, the test sample was taken from the granulated granule sample. The area of ​​the prebiotic vitrified matrix covered area and the visible area of ​​the outer surface of the freeze-dried powder of the food processing strain in the microscopic image of the granule surface were identified. The surface coverage of a single particle was calculated as "area of ​​prebiotic vitrified matrix covered area / (area of ​​prebiotic vitrified matrix covered area + area of ​​visible area of ​​outer surface of freeze-dried powder of food processing strain) × 100%". The arithmetic mean of the surface coverage of at least 100 particles in the same sample was taken as the surface coverage of the sample.

[0023] Furthermore, D50 is the particle size corresponding to a cumulative volume fraction of 50% in the particle size distribution, and water activity aw is the water activity value recorded when the reading is stable after the sample is placed in a closed measurement chamber. Before entering the next preparation step, samples of prebiotic vitrified matrix powder, prebiotic vitrified matrix protected live bacteria particles, low-moisture tableting mixture and tablets are taken to determine D50, moisture content or water activity aw, and the determination results are used as the release caliber between the pre-drying, granulation, mixing, tableting and sealing packaging steps.

[0024] Furthermore, during the determination of viable bacteria count, the high-viable-bacteria probiotic nutritional tablets were pulverized and prepared into a sample homogenate. The viable count of lactic acid bacteria was counted according to GB4789.35-2023, and the viable count of bifidobacteria was counted according to GB4789.34-2016. When the sample contained both lactic acid bacteria and bifidobacteria, the viable counts of lactic acid bacteria and bifidobacteria were recorded separately, and the sum of the two viable counts was taken as the total viable count of the sample.

[0025] Furthermore, the viable bacteria retention rate after tableting is calculated as "the number of viable bacteria in the tablet after tableting / the theoretical number of viable bacteria in the low-humidity tableting mixture before tableting × 100%". The theoretical number of viable bacteria in the low-humidity tableting mixture before tableting is calculated from the mass of the vitrified matrix-protected viable bacteria particles entering the tableting step and the number of viable bacteria in the particles before tableting. The viable bacteria retention rate after storage is calculated as "the number of viable bacteria in the tablet after storage / the number of viable bacteria in the tablet when the sealed packaging is completed × 100%".

[0026] Furthermore, in the preparation of the low-moisture tableting dry matrix, food-grade starch and food-grade erythritol are mixed at a temperature of 15–25℃, a relative humidity of 5–25%, and an absolute pressure of 0.09–0.11 MPa for 8–25 min, according to the corresponding mass ratio of the two in the composition of the high-active-bacteria probiotic nutritional tablets. Then, food additive silica is added according to the corresponding mass ratio of the food additive silica in the composition of the high-active-bacteria probiotic nutritional tablets, and the mixture is mixed for another 3–12 min to obtain a low-moisture tableting dry matrix with a moisture content of 0.3–5.0 wt% and a water activity aw of 0.03–0.20. This low-moisture tableting dry matrix is ​​then used to prepare low-moisture tableting mixtures.

[0027] Furthermore, during the preparation of the low-moisture tableting mixture, the prebiotic vitrified matrix protected live bacteria particles are mixed with the low-moisture tableting dry matrix at a temperature of 15–25°C and a relative humidity of 5–25% for 8–25 min. The resulting low-moisture tableting mixture has a moisture content of 0.5–3.5 wt%, a water activity aw of 0.05–0.23, and a bulk density of 0.30–0.90 g / mL. This low-moisture tableting mixture is then fed into the tableting step.

[0028] Furthermore, in the tableting step, the low-moisture tableting mixture is compressed into tablets with a single tablet weight of 0.6–1.8g under the conditions of tableting force of 3–12kN, tableting machine turntable speed of 10–60rpm, and tableting temperature of 20–35℃. The resulting tablets have a water activity aw of 0.05–0.25 and then enter the food-grade nitrogen atmosphere sealing step.

[0029] Furthermore, in the sealing packaging step, the tablets are sealed under a food-grade nitrogen atmosphere with an oxygen content of 0.1–5.0 vol%, and the water vapor permeability of the sealed packaging is 0.01–1.00 g / (m²). 2 •d) The relative humidity inside the packaging is 1–20%, and the sealed tablets are used as the starting sample for determining the viability retention rate after storage.

[0030] Furthermore, the inter-batch variation coefficient was calculated using the average values ​​of the three batches of samples as the calculation object, according to the formula "standard deviation of batch average value / arithmetic mean of batch average value × 100%". The D50, water activity aw, and viable bacteria retention rate after tableting were recorded for the three batches of samples, and the obtained inter-batch variation coefficient was used as the quality control result for the consistency between batches of prebiotic vitrification matrix-protected viable bacteria particles and high viable bacteria probiotic nutritional tablets.

[0031] As another aspect of this invention, it employs low-temperature, low-humidity mixing, controlled tableting, and low-oxygen sealing to achieve, maintain, or amplify the aforementioned synergistic effects. In existing technologies, reducing mixing humidity alone can mitigate moisture absorption and inactivation, but may affect tablet weight and batch-to-batch consistency due to insufficient powder flowability. Increasing compression force alone can improve tablet integrity, but may exacerbate pressure damage to live bacteria. This invention, based on the prebiotic vitrified matrix protecting the live bacteria particles, continuously controls material contact temperature, relative humidity, mixing time, compression force, tableting temperature, and packaging oxygen content. This prevents the particle protective layer from being damaged by moisture absorption during processing, while the compressed dry matrix provides support for shaping. Furthermore, the low-oxygen, low-humidity sealing reduces the impact of moisture and oxygen on live bacteria during storage, thus maintaining a balance between processing flowability, tablet structure, and storage stability throughout the entire preparation process.

[0032] Inulin and food-grade resistant dextrin primarily function as a prebiotic vitrified matrix and protect against low surface water activity, which helps reduce moisture exposure during granulation, tableting, and storage of freeze-dried microbial preparations for food processing. However, pursuing a high protection ratio for either alone may lead to increased particle volume, reduced flow, and a narrower tableting window. Food-grade starch, food-grade erythritol, and food additive silica primarily function as dry matrix shaping, dilution, and flow aids, which are beneficial for controlling tablet hardness, friability, and tablet weight uniformity. However, relying solely on the dry matrix to improve tableting quality may still reduce viable cell retention due to compression stress and the moisture absorption pathways of excipients. This invention achieves a balance between tablet structural integrity and viable cell storage stability by matching the mass ratio of prebiotic vitrified matrix to freeze-dried powder, particle D50, low-humidity mixing conditions, and low-oxygen sealing. This reduces the impact of moisture and oxygen on viable cells in the protective layer, improves tableting and flow conditions with the dry matrix, and ultimately balances tablet structural integrity with viable cell storage stability.

[0033] Beneficial technical effects 1. This invention uses inulin and food-grade resistant dextrin to form a prebiotic vitrified matrix, and distributes this matrix on the surface of freeze-dried powder of microbial preparations for food processing. This can form live bacteria particles to protect the environment under low water activity conditions, while retaining the properties of prebiotics and dietary fiber. Compared with directly mixing freeze-dried powder with tableting excipients, this method is more conducive to reducing the impact of moisture fluctuations on live bacteria during processing and storage.

[0034] 2. This invention combines prebiotic vitrified matrix to protect live bacteria particles with food-grade starch, food-grade erythritol, and food additive silica to form a low-moisture tableting system. This system can improve the tablet forming state through the compressibility, filling and flowability of the dry matrix, and avoid simply increasing the tableting force to obtain hardness, thereby achieving a better balance between tablet hardness, friability, disintegration time and live bacteria retention rate.

[0035] 3. The present invention limits the low-temperature and low-humidity mixing, low-temperature drying, controlled tableting, and low-oxygen food-grade nitrogen sealing during the preparation process. This allows the release of granules, tableting and mixing, tableting and packaging to be controlled around aw, moisture content and oxygen content. Compared with the scheme that only controls the final packaging, it is more conducive to improving batch-to-batch quality consistency and room temperature sealed storage stability.

[0036] 4. This invention establishes a continuous evaluation chain from raw material particles to finished tablets by using quality control metrics such as D50, surface coverage, Tg, water activity (aw), viable cell retention rate, and batch-to-batch coefficient of variation. This allows for a correlation between the product's structural state, processing state, and storage effect, facilitating release judgment and process window adjustments in industrial production. Attached Figure Description

[0037] Figure 1This figure shows the effect of the prebiotic vitrification matrix content on the viability retention rate and tablet hardness after tableting.

[0038] Figure 2 This figure shows the effect of the ratio of prebiotic vitrified matrix to lyophilized powder on the viable cell retention rate and tablet hardness after compression.

[0039] Figure 3 This figure shows the effect of compression force on the viable cell retention rate and tablet hardness after compression.

[0040] Figure 4 This figure shows the effect of tablet water activity (aw) on the viable cell retention rate after tableting and the viable cell retention rate after 3 months of storage.

[0041] Figure 5 The DSC heat flow-temperature curves for Example 1, Comparative Example 2, and Comparative Example 4 are shown.

[0042] Figure 6 The graph shows the relationship between the midpoint temperature of Tg and the water activity aw for Example 1, Comparative Example 2, and Comparative Example 4.

[0043] Figure 7 The volumetric particle size distribution diagrams of the live bacteria input materials for Examples 1, 3, and 8 are shown.

[0044] Figure 8 The cumulative volumetric particle size distribution of the live bacteria input materials for Examples 1, 3, and 8 is shown in the diagram.

[0045] Figure 9 The original scatter plots and mean ± SD plots show the surface coverage of Examples 1, 3, and 8.

[0046] Figure 10 The original scatter plot and mean ± SD of tablet hardness for Example 1, Comparative Example 5, Comparative Example 6 and Comparative Example 9 are shown.

[0047] Figure 11 The original scatter plot and mean ± SD of the friability of Example 1, Comparative Example 5, Comparative Example 6 and Comparative Example 9 are shown.

[0048] Figure 12 The original scatter plot and mean ± SD of the disintegration time for Example 1, Comparative Example 5, Comparative Example 6 and Comparative Example 9 are shown.

[0049] Figure 13 The graphs show the process-storage curves of viable cell retention rate for Examples 1, 5, 7, and 8.

[0050] Figure 14 The graph shows the relationship between water activity (aw) and viable cell retention rate after storage for Examples 1, 2, 8 and 4.

[0051] Figure 15 The images show a comparison of the SEM morphology of the final product of Example 1 and the final product of Comparative Example 8. Specifically, a is a medium-magnification SEM image of the interface between the protected live bacteria particles and the tableting matrix in the final product of Example 1; b is a medium-magnification SEM image of the directly mixed structure of the lyophilized bacterial powder and the excipient matrix in the final product of Comparative Example 8; c is a high-magnification SEM image of the prebiotic vitrified matrix covering the surface of the protected live bacteria particles in the final product of Example 1; and d is a high-magnification SEM image of the directly contacting interface between the lyophilized live bacteria powder and the tableting excipients in the final product of Comparative Example 8. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0053] Example 1 In this embodiment, 1000g of high-live-bacteria probiotic nutritional tablets were prepared, in round compressed tablet form, with each tablet weighing 0.6g. The composition of the finished product in this embodiment, based on a total mass of 100wt%, is as follows: 30.0wt% prebiotic vitrified matrix-protected live bacteria particles, 40.0wt% food-grade starch, 29.2wt% food-grade erythritol, and 0.8wt% food additive silicon dioxide. The freeze-dried microbial preparation for food processing was selected from *Lactobacillus plantarum* freeze-dried powder, with a live bacteria count of 1.8 × 10⁻⁶. 10 The product contains CFU / g, has a moisture content of 0.5wt%, a water activity (aw) of 0.03, and is made from freeze-dried powder of microbial inoculum for food processing. It is commercially available and meets the requirements for microbial inoculum for food processing. Inulin and food-grade resistant dextrin are both food-grade and commercially available, with a moisture content not exceeding 3.0wt% respectively.

[0054] S1: 60 parts by weight of inulin and 40 parts by weight of food-grade resistant dextrin were put into a low-humidity mixer and mixed for 8 minutes at 30°C and 0.09 MPa to obtain a prebiotic mixed powder. Then, it was pre-dried for 1 hour at 30°C and 0.09 MPa to make the moisture content of the prebiotic mixed powder reach 0.3 wt% and the water activity aw reach 0.03, so as to obtain a prebiotic glass matrix powder with a D50 of 20 μm.

[0055] S2: Add 100 parts by weight of *Bacillus plantarum* freeze-dried powder and 200 parts by weight of prebiotic vitrified matrix powder to a low-humidity mixer in the following order: first add the prebiotic vitrified matrix powder, then add the *Bacillus plantarum* freeze-dried powder. Mix at 120 rpm for 5 minutes at 15°C, 5% relative humidity, and 0.09 MPa absolute pressure to obtain a low-humidity premix. Spray 0.5 parts by weight of food-grade deionized water into the low-humidity premix and granulate at 150 rpm for 5 minutes at 20°C, 5% relative humidity, and 0.09 MPa absolute pressure to obtain wet granules.

[0056] S3: The wet granules were dried at 25℃ and 0.09MPa absolute pressure for 0.5h. The drying was completed when the water activity (aw) of the granules reached 0.05. Subsequently, the granules were sized, and obviously agglomerated particles were removed by sieving, resulting in a granule with a D50 of 80μm, a surface coverage of 60%, and a viable bacterial count of 5.8×10⁻⁶ before tableting. 9 CFU / g of prebiotic vitrified matrix protects live bacteria particles.

[0057] S4: 40 parts by weight of food-grade starch and 29.2 parts by weight of food-grade erythritol were mixed for 8 minutes at 15°C, 5% relative humidity, and 0.09 MPa absolute pressure. Then, 0.8 parts by weight of food additive silicon dioxide were added and the mixture was mixed for another 3 minutes to obtain a low-moisture tableting dry matrix. The moisture content of the low-moisture tableting dry matrix was 0.3 wt%, and the water activity (aw) was 0.03.

[0058] S5: Weigh the prebiotic vitrified matrix protected live bacteria granules and the low-moisture tableting dry matrix obtained in step S4 according to the finished product composition of this embodiment, and mix them for 8 minutes at a temperature of 15°C and a relative humidity of 5% to obtain a low-moisture tableting mixture. The moisture content of the low-moisture tableting mixture is 0.5 wt%, the water activity aw is 0.05, and the bulk density is 0.30 g / mL.

[0059] S6: The low-moisture tableting mixture is fed into the tableting equipment and compressed into tablets under the conditions of a tableting force of 3kN, a tableting machine turntable speed of 10rpm, and an exit temperature of 20℃. The tablets are sealed in a food-grade nitrogen atmosphere with an oxygen content of 0.1vol%, and the water vapor permeability of the sealed packaging is 0.01g / (m³). 2 ·d), the relative humidity inside the packaging is 1%.

[0060] Quality testing methods and results: Tablet samples from this embodiment were tested for water activity, tablet hardness, friability, disintegration time, viable count, and surface coverage. Water activity was measured as the stable value of a water activity meter reading; tablet hardness was measured using a tablet hardness tester; friability was calculated as the mass loss rate after treatment at a specified rotation speed; disintegration time was measured as the time it took for the tablet to completely disintegrate in an aqueous medium at 37°C; viable count was determined using the lactic acid bacteria counting method and converted to a per-tablet ratio. In this embodiment, the tablet hardness was 30 N, friability was 1.00 wt%, disintegration time was 3 min, moisture content was 0.5 wt%, water activity (aw) was 0.05, viable count after compression was 96%, viable count after 3 months of sealed storage in the dark at 25°C was 95%, and the factory viable count was 1.0 × 10⁶ per tablet. 9 CFU.

[0061] Features and application scenarios of this embodiment: This embodiment adopts relatively mild low temperature and low humidity process conditions, the amount of prebiotic vitrification matrix protecting live bacteria particles is relatively low, the tablet water activity and single tablet weight are in the low value range, which is suitable for probiotic nutritional supplementation scenarios that require low sugar content, low tablet weight and rapid disintegration.

[0062] Example 2 Raw materials and proportions High-live-bacteria probiotic nutritional tablets were prepared according to a production scale of 1200g. The product is in tablet form, with each tablet weighing 1.8g. The composition of the finished product, based on a total mass of 100wt%, is as follows: 70.0wt% prebiotic vitrified matrix protecting live bacteria particles, 24.0wt% food-grade starch, 5.0wt% food-grade erythritol, and 1.0wt% food additive silicon dioxide. The freeze-dried powder of the bacterial strain preparation for food processing is freeze-dried Lactobacillus rhamnosus powder with a live bacteria count of 2.5 × 10⁻⁶. 11 The concentration is CFU / g, with a moisture content of 5.0 wt% and a water activity (aw) of 0.15. Inulin, food-grade resistant dextrin, food-grade starch, food-grade erythritol, and food additive silicon dioxide are all food-grade and commercially available.

[0063] Preparation of live bacteria granules 95 parts by weight of inulin and 5 parts by weight of food-grade resistant dextrin were added to a mixing device and mixed for 25 minutes at 45°C and 0.11 MPa absolute pressure, followed by pre-drying for 6 hours. The resulting prebiotic vitrified matrix powder was controlled to have a moisture content of 4.0 wt%, a water activity (aw) of 0.18, and a D50 of 180 μm. Subsequently, 100 parts by weight of Lactobacillus rhamnosus lyophilized powder were mixed with 200 parts by weight of prebiotic vitrified matrix powder under the following conditions: 25°C, 25% relative humidity, 0.11 MPa absolute pressure, and 20 minutes. 8.0 parts by weight of food-grade deionized water were sprayed into the resulting low-moisture premix, and granulation was performed for 25 minutes at 32°C, 25% relative humidity, and 0.11 MPa absolute pressure.

[0064] Drying, granulation and tableting The wet granules were dried at 35℃ and 0.11 MPa for 3.0 h until the water activity (aw) reached 0.20. The granules were then granulated to obtain a D50 of 250 μm, a surface coverage of 95%, and a viable bacterial count of 8.0 × 10⁻⁶ before tableting. 10 CFU / g of prebiotic vitrified matrix protecting live bacteria granules. The low-moisture tableting dry matrix was prepared by mixing 24 parts by weight of food-grade starch, 5 parts by weight of food-grade erythritol, and 1.0 part by weight of food additive silicon dioxide. The mixing temperature was 25℃, the relative humidity was 25%, and the absolute pressure was 0.11MPa. The first stage of mixing was 25 min, and after adding the food additive silicon dioxide, mixing continued for 12 min. The resulting low-moisture tableting dry matrix had a moisture content of 5.0 wt% and a water activity (aw) of 0.20.

[0065] Mixed Packaging Weigh out the prebiotic vitrified matrix protective live bacteria granules and the low-moisture tableting dry matrix according to the finished product composition. Mix them for 25 min at 25℃ and 25% relative humidity. The resulting low-moisture tableting mixture has a moisture content of 3.5 wt%, a water activity (aw) of 0.23, and a bulk density of 0.90 g / mL. Compress the low-moisture tableting mixture into tablets at a compression force of 12 kN, a tablet press turntable speed of 60 rpm, and an output temperature of 35℃. Seal the tablets in a food-grade nitrogen atmosphere with an oxygen content of 5.0 vol%, with a water vapor permeation rate of 1.00 g / (m³). 2 •d) The relative humidity inside the packaging is 20%. The material contact temperature is controlled below 35℃ throughout the preparation process, and the cumulative time the material is exposed to an environment with a relative humidity higher than 25% is 20 minutes.

[0066] Quality testing methods and results The tablets of this embodiment were tested using a water activity meter, tablet hardness tester, friability tester, disintegration meter, and viable cell count method. The results showed that the tablets of this embodiment had a hardness of 120 N, a friability of 0.05 wt%, a disintegration time of 25 min, a moisture content of 3.5 wt%, a water activity (aw) of 0.25, a viable cell retention rate of 98% after compression, and a viable cell retention rate of 40% after 12 months of sealed, light-protected storage at 30°C. The factory viable cell count was 1.0 × 10⁶ per tablet. 11 CFU.

[0067] Features of the solution in this embodiment This embodiment employs a high proportion of prebiotic vitrified matrix to protect live bacteria particles and high tableting strength. The tablet hardness, single tablet weight, particle size, particle coverage, and packaging barrier conditions reflect a high-load process combination, which is suitable for nutritional tablet products with high requirements for single tablet live bacteria input and tablet structural integrity.

[0068] Example 3 I. Preparation Object and Strain Status: This example prepares 1500g high-viable-bacteria probiotic nutritional tablets, each weighing 1.2g. The tablets contain *Lactobacillus plantarum* and *Bifidobacterium animalis* subsp. *lactamase*, with a viable bacteria ratio of 1:1 in the freeze-dried powder of the food processing strain preparation. The total viable bacteria count of the freeze-dried powder of the food processing strain preparation is 1.4 × 10⁻⁶. 11 The product composition in this embodiment, based on a total mass of 100wt%, is as follows: 59.8wt% prebiotic vitrified matrix protected live bacteria granules, 10.0wt% food-grade starch, 30.0wt% food-grade erythritol, and 0.2wt% food additive silicon dioxide.

[0069] II. Preparation of Prebiotic Vitrified Matrix Powder: 75 parts by weight of inulin and 25 parts by weight of food-grade resistant dextrin were mixed for 16 min to obtain a prebiotic mixed powder. The prebiotic mixed powder was pre-dried at 38℃ and 0.10 MPa absolute pressure for 3 h to obtain a moisture content of 2.0 wt%, a water activity (aw) of 0.10, and a D50 of 100 μm, thus obtaining the prebiotic vitrified matrix powder. D-trehalose dihydrate was separately taken and made to account for 1 wt% of the total mass of the prebiotic vitrified matrix. This was used as an optional auxiliary component in the trehalose-containing embodiment for subsequent particle construction, and the total amount of the prebiotic vitrified matrix powder and D-trehalose dihydrate was used as the amount of prebiotic vitrified matrix in the subsequent particle construction.

[0070] III. Construction of Live Bacterial Granules: 100 parts by weight of freeze-dried microbial inoculum powder for food processing and 900 parts by weight of prebiotic vitrification matrix (containing prebiotic vitrification matrix powder and a corresponding proportion of D-trehalose dihydrate) were added to a mixing device and mixed for 12 min at 20℃, 15% relative humidity, and 0.10 MPa absolute pressure to obtain a low-moisture premix. 4.0 parts by weight of deionized water for food production was sprayed into the low-moisture premix, and granulation was carried out for 15 min at 26℃, 15% relative humidity, and 0.10 MPa absolute pressure. Subsequently, the granules were dried for 1.5 h at 30℃ and 0.10 MPa absolute pressure to achieve a water activity (aw) of 0.12. After granulation, the resulting granules had a D50 of 160 μm, a surface coverage of 78%, and a viable count of 1.4 × 10⁻⁶ before tableting. 10 CFU / g of prebiotic vitrified matrix protects live bacteria particles.

[0071] IV. Low-Moisture Tableting and Sealing: 10 parts by weight of food-grade starch and 30 parts by weight of food-grade erythritol were mixed for 15 minutes at 20°C, 15% relative humidity, and 0.10 MPa absolute pressure. Then, 0.2 parts by weight of food additive silica were added and mixing continued for 6 minutes to obtain the low-moisture tableting dry matrix. According to the finished product composition of this embodiment, prebiotic vitrified matrix protective live bacteria granules and the low-moisture tableting dry matrix were weighed and mixed for 15 minutes at 20°C and 15% relative humidity to obtain the low-moisture tableting mixture. The low-moisture tableting mixture had a moisture content of 1.8 wt%, a water activity (aw) of 0.12, and a bulk density of 0.55 g / mL. The low-moisture tableting mixture was compressed into tablets under a tableting force of 6 kN, a tablet press turntable speed of 30 rpm, and an output temperature of 28°C, and then sealed in a food-grade nitrogen atmosphere with an oxygen content of 2.0 vol%. The water vapor permeability of the sealed packaging was 0.50 g / (m³). 2 ·d), the relative humidity inside the packaging is 10%.

[0072] V. Quality Testing Methods and Results: In this embodiment, D50 was determined using particle size distribution statistics, water activity (aw) was measured using stable readings, surface coverage was identified using microscopic image area recognition, and viable bacteria counts were recorded separately for lactic acid bacteria and bifidobacteria, with the total viable bacteria count calculated. The test results were as follows: tablet hardness 70 N, friability 0.40 wt%, disintegration time 12 min, moisture content 1.8 wt%, water activity (aw) 0.12, viable bacteria retention rate after compression 90%, viable bacteria retention rate after 6 months of sealed storage in the dark at 25°C 72%, and the factory viable bacteria count was 9.0 × 10⁻⁶ per tablet. 9 CFU. The inter-batch coefficient of variation for D50 of the three batches of prebiotic vitrified matrix-protected live bacteria granules was 2%, the inter-batch coefficient of variation for water activity (aw) was 1%, and the inter-batch coefficient of variation for viable bacteria retention rate after tableting was 3%.

[0073] VI. Applicable Scenarios of this Embodiment: This embodiment uses a combination of two strains, a high proportion of food-grade erythritol, and a medium compression force, which is suitable for nutritional tablet products that take into account flavor, tablet disintegration, and live bacteria input. It can also be used to demonstrate the feasibility of different strain combinations in a low-moisture tableting system.

[0074] Example 4 A 2000g high-viable-bacteria probiotic nutritional tablet was prepared using a mixed freeze-dried powder of Bifidobacterium animalis subsp. lactis and Lactobacillus acidophilus as a food processing microbial culture preparation. The viable bacteria count of the freeze-dried powder used in this embodiment was 5.0 × 10⁻⁶. 11 The product contains CFU / g of prebiotics, has a moisture content of 4.0 wt%, a water activity (aw) of 0.12, and a viable count ratio of *Bifidobacterium animalis* subsp. *lactospirum* to *Lactobacillus acidophilus* of 1:1. The finished tablets are round compressed tablets, each weighing 1.5 g. The product composition (100 wt%) consists of 40.0 wt% prebiotic vitrified matrix-protected live bacteria granules, 29.5 wt% food-grade starch, 30.0 wt% food-grade erythritol, and 0.5 wt% food additive silicon dioxide.

[0075] 85 parts by weight of inulin and 15 parts by weight of food-grade resistant dextrin were mixed for 20 min and pre-dried for 5 h at 42 °C and 0.10 MPa absolute pressure to obtain a prebiotic vitrification matrix powder with a moisture content of 3.0 wt%, a water activity (aw) of 0.15, and a D50 of 140 μm. D-trehalose dihydrate was added as an optional cofactor in the prebiotic vitrification matrix, making it account for 20 wt% of the total mass of the prebiotic vitrification matrix, and the total amount of the prebiotic vitrification matrix powder and D-trehalose dihydrate was 2000 parts by weight.

[0076] 100 parts by weight of freeze-dried microbial culture preparation for food processing and 2000 parts by weight of prebiotic vitrification matrix (containing prebiotic vitrification matrix powder and a corresponding proportion of D-trehalose dihydrate) were added to a mixing device and mixed for 18 min at 22℃, 20% relative humidity, and 0.10 MPa absolute pressure to obtain a low-moisture premix. 6.5 parts by weight of deionized water for food production were sprayed into the low-moisture premix, and granulation was carried out for 20 min at 30℃, 20% relative humidity, and 0.10 MPa absolute pressure to obtain wet granules. The wet granules were dried for 2.5 h at 32℃ and 0.10 MPa absolute pressure. After drying, the granules were sized to obtain a D50 of 220 μm, a water activity (aw) of 0.18, a surface coverage of 90%, and a viable count of 2.3 × 10⁻⁶ before tableting. 10 CFU / g of prebiotic vitrified matrix protects live bacteria particles.

[0077] The low-moisture tableting dry matrix was prepared using 29.5 parts by weight of food-grade starch, 30.0 parts by weight of food-grade erythritol, and 0.5 parts by weight of food additive silica. The process conditions were: temperature 22℃, relative humidity 20%, and absolute pressure 0.10 MPa. The first stage of mixing was 20 min, followed by 9 min of mixing after adding the food additive silica. The moisture content of the low-moisture tableting dry matrix was 2.5 wt%, and the water activity (aw) was 0.12. The prebiotic vitrified matrix protecting live bacteria granules and the low-moisture tableting dry matrix were mixed according to the finished product composition. The mixing conditions were: temperature 22℃, relative humidity 20%, and mixing for 20 min. The resulting low-moisture tableting mixture had a moisture content of 2.5 wt%, a water activity (aw) of 0.18, and a bulk density of 0.70 g / mL.

[0078] The low-moisture tableting mixture was compressed into tablets under the conditions of a compression force of 9 kN, a tablet press turntable speed of 45 rpm, and an output temperature of 30°C. The tablets were sealed in a food-grade nitrogen atmosphere with an oxygen content of 3.0 vol%, and the water vapor permeability of the sealed packaging was 0.20 g / (m³). 2 •d) The relative humidity inside the packaging is 5%. The material contact temperature is controlled below 30℃ throughout the preparation process, and the cumulative time the material is exposed to an environment with a relative humidity higher than 25% is 8 minutes.

[0079] Quality testing methods and results: The tablet hardness (aw) was determined using a water activity meter; moisture content was determined using the loss on drying method; hardness was determined using a tablet hardness tester; mass loss rate was determined using a friability tester; disintegration time was determined using a disintegration meter; and viable cell count was used to calculate the viable cell retention rate after tableting and after storage. The test results were: tablet hardness 95 N, friability 0.20 wt%, disintegration time 18 min, moisture content 2.5 wt%, water activity (aw) 0.18, viable cell retention rate after tableting 80%, viable cell retention rate after 12 months of sealed storage in the dark at 25℃ 65%, and the factory viable cell count was 1.1 × 10⁶ per tablet. 10 CFU. The inter-batch coefficient of variation for D50 of the three batches of prebiotic vitrified matrix-protected live bacteria granules was 15%, the inter-batch coefficient of variation for water activity (aw) was 12%, and the inter-batch coefficient of variation for viable bacteria retention rate after tableting was 20%.

[0080] The process features and application directions of this embodiment: This embodiment adopts a high prebiotic vitrification matrix to food processing microbial preparation freeze-dried powder mass ratio, and introduces a high proportion of D-trehalose dihydrate optional excipient, which is suitable for long-term sealed storage of tablet products containing Bifidobacterium, and is used to reflect the synergistic relationship between low humidity protective granules, low oxygen packaging and batch-to-batch consistency control.

[0081] Comparative Example 1: Essentially the same as Example 1, except that the content of prebiotic vitrified matrix-protected live bacteria particles was adjusted to 20.0 wt%, food-grade starch to 50.0 wt%, food-grade erythritol to 29.2 wt%, and the food additive silica remained at 0.8 wt%. This change occurred during the finished product ingredient preparation step; other conditions remained the same: 1.8 × 10⁸ live bacteria count in the freeze-dried Lactobacillus plantarum powder. 10 CFU / g, prebiotic vitrified matrix to lyophilized powder mass ratio 2:1, D50 of protected live bacteria particles is 80μm, aw of protected live bacteria particles is 0.05, A3 mixing temperature 15℃, relative humidity 5%, absolute pressure 0.09MPa, mixing for 5min, A4 spraying water 0.5 parts by mass, granulation temperature 20℃, granulation for 5min, A5 drying temperature 25℃, drying for 0.5h, S2 mixing temperature 15℃, relative humidity 5%, mixing for 8min, S3 tableting force 3kN, turntable speed 10rpm, tableting temperature 20℃, S4 oxygen content 0.1vol%, single tablet weight 0.6g.

[0082] Comparative Example 2: Essentially the same as Example 1, except that the mass ratio of the prebiotic vitrified matrix to the freeze-dried powder of the microbial inoculum preparation for food processing was adjusted to 1:1. 100 parts by mass of *Lactobacillus plantarum* freeze-dried powder were mixed with 100 parts by mass of the prebiotic vitrified matrix powder. This change occurred in step A3, the low-humidity mixing step. Other conditions remained the same: the finished product contained 30.0 wt% prebiotic vitrified matrix protected live bacteria particles, 40.0 wt% food-grade starch, 29.2 wt% food-grade erythritol, and 0.8 wt% food additive silicon dioxide. The live bacteria granules have a D50 of 80 μm and the protected live bacteria granules have an aw of 0.05 μm. The mixing temperature (A3) is 15℃, relative humidity is 5%, absolute pressure is 0.09 MPa, and mixing time is 5 min. The water spraying temperature (A4) is 0.5 parts by weight, granulation temperature is 20℃, and granulation time is 5 min. The drying temperature (A5) is 25℃, and drying time is 0.5 h. The mixing temperature (S2) is 15℃, relative humidity is 5%, and mixing time is 8 min. The tableting force (S3) is 3 kN, turntable speed is 10 rpm, and tablet output temperature is 20℃. The oxygen content (S4) is 0.1 vol%, and the weight of a single tablet is 0.6 g.

[0083] Comparative Example 3: Essentially the same as Example 1, except that the D50 of the protected live bacteria particles was adjusted to 50 μm. This change was achieved by altering the granulation and sieving conditions. Other conditions remained the same: 30.0 wt% of prebiotic vitrified matrix protected live bacteria particles, 40.0 wt% of food-grade starch, 29.2 wt% of food-grade erythritol, 0.8 wt% of food additive silica, and 1.8 × 10⁻⁶ live bacteria count of *Lactobacillus plantarum* freeze-dried powder. 10CFU / g, prebiotic vitrified matrix to lyophilized powder mass ratio 2:1, protected live bacteria particle aw 0.05, A3 mixing temperature 15℃, relative humidity 5%, absolute pressure 0.09MPa, mixing 5min, A4 spraying water 0.5 parts by mass, granulation temperature 20℃, granulation 5min, A5 drying temperature 25℃, drying 0.5h, S2 mixing temperature 15℃, relative humidity 5%, mixing 8min, S3 tableting force 3kN, turntable speed 10rpm, tableting temperature 20℃, S4 oxygen content 0.1vol%, single tablet weight 0.6g.

[0084] Comparative Example 4: Essentially the same as Example 1, except that the water activity (aw) of the prebiotic vitrified matrix-protected live bacteria particles was adjusted to 0.30. This change was achieved by shortening the drying time to 0.2 hours. Other conditions remained the same: 30.0 wt% prebiotic vitrified matrix-protected live bacteria particles, 40.0 wt% food-grade starch, 29.2 wt% food-grade erythritol, 0.8 wt% food additive silica, and 1.8 × 10⁻⁶ live bacteria count of *Lactobacillus plantarum* freeze-dried powder. 10 CFU / g, prebiotic vitrified matrix to lyophilized powder mass ratio 2:1, protected live bacteria particle D50 is 80μm, A3 mixing temperature 15℃, relative humidity 5%, absolute pressure 0.09MPa, mixing for 5min, A4 spraying water 0.5 parts by mass, granulation temperature 20℃, granulation for 5min, S2 mixing temperature 15℃, relative humidity 5%, mixing for 8min, S3 tableting force 3kN, turntable speed 10rpm, tableting temperature 20℃, S4 oxygen content 0.1vol%, single tablet weight 0.6g.

[0085] Comparative Example 5: Basically the same as Example 1, except that the tableting force in step S3 was adjusted to 15kN, which occurred during the tableting step; other conditions remained the same: 30.0wt% prebiotic vitrified matrix protected live bacteria particles, 40.0wt% food-grade starch, 29.2wt% food-grade erythritol, 0.8wt% food additive silica, and 1.8×10⁻⁶ live bacteria count of *Lactobacillus plantarum* freeze-dried powder. 10 CFU / g, prebiotic vitrified matrix to lyophilized powder mass ratio 2:1, D50 of protected live bacteria particles is 80μm, aw of protected live bacteria particles is 0.05, A3 mixing temperature 15℃, relative humidity 5%, absolute pressure 0.09MPa, mixing for 5min, A4 spraying water 0.5 parts by mass, granulation temperature 20℃, granulation for 5min, A5 drying temperature 25℃, drying for 0.5h, S2 mixing temperature 15℃, relative humidity 5%, mixing for 8min, turntable speed 10rpm, tablet output temperature 20℃, S4 oxygen content 0.1vol%, single tablet weight 0.6g.

[0086] Comparative Example 6: Essentially the same as Example 1, except that the content of the food additive silica was adjusted to 0.05 wt%, and the food-grade erythritol was adjusted to 29.95 wt%. This change occurred during the finished product ingredient preparation step. Other conditions remained the same: 30.0 wt% prebiotic vitrified matrix protected live bacteria particles, 40.0 wt% food-grade starch, and 1.8 × 10⁻⁶ live bacteria count of *Lactobacillus plantarum* freeze-dried powder. 10 CFU / g, prebiotic vitrified matrix to lyophilized powder mass ratio 2:1, D50 of protected live bacteria particles is 80μm, aw of protected live bacteria particles is 0.05, A3 mixing temperature 15℃, relative humidity 5%, absolute pressure 0.09MPa, mixing for 5min, A4 spraying water 0.5 parts by mass, granulation temperature 20℃, granulation for 5min, A5 drying temperature 25℃, drying for 0.5h, S2 mixing temperature 15℃, relative humidity 5%, mixing for 8min, S3 tableting force 3kN, turntable speed 10rpm, tableting temperature 20℃, S4 oxygen content 0.1vol%, single tablet weight 0.6g.

[0087] Comparative Example 7: Essentially the same as Example 1, except that the oxygen content in the food-grade nitrogen atmosphere during sealing packaging in step S4 was adjusted to 10.0 vol%. This change occurred during the sealing packaging step. Other conditions remained the same: 30.0 wt% prebiotic vitrified matrix protected live bacteria particles, 40.0 wt% food-grade starch, 29.2 wt% food-grade erythritol, 0.8 wt% food additive silica, and 1.8 × 10⁻⁶ live bacteria count of *Lactobacillus plantarum* freeze-dried powder. 10 CFU / g, prebiotic vitrified matrix to lyophilized powder mass ratio 2:1, D50 of protected live bacteria particles is 80μm, aw of protected live bacteria particles is 0.05, A3 mixing temperature 15℃, relative humidity 5%, absolute pressure 0.09MPa, mixing for 5min, A4 spraying water 0.5 parts by mass, granulation temperature 20℃, granulation for 5min, A5 drying temperature 25℃, drying for 0.5h, S2 mixing temperature 15℃, relative humidity 5%, mixing for 8min, S3 tableting force 3kN, turntable speed 10rpm, tableting temperature 20℃, single tablet weight 0.6g.

[0088] Comparative Example 8: Essentially the same as Example 1, except that the surface protective structures of inulin and food-grade resistant dextrin in the prebiotic vitrified matrix protecting the live bacteria particles were removed. Instead, *Lactobacillus plantarum* freeze-dried powder was directly mixed with food-grade starch, food-grade erythritol, and food additive silica and then compressed into tablets. This change occurred in the particle construction steps A2 to A6. Other conditions remained the same: the calculated input amounts of live bacteria in the finished product were 30.0 wt%, food-grade starch 40.0 wt%, food-grade erythritol 29.2 wt%, and food additive silica 0.8 wt%, with a live bacteria count of 1.8 × 10⁻⁶ in the *Lactobacillus plantarum* freeze-dried powder. 10CFU / g, S2 mixing temperature 15℃, relative humidity 5%, mixing 8min, S3 tableting force 3kN, turntable speed 10rpm, tableting temperature 20℃, S4 oxygen content 0.1vol%, single tablet weight 0.6g. This comparative example was used to investigate the synergistic relationship between prebiotic vitrification matrix surface protection and low-humidity compressed dry matrix.

[0089] Comparative Example 9: Essentially the same as Example 1, except that inulin and food-grade resistant dextrin were retained to form a prebiotic vitrified matrix protecting the live bacteria particles, but the food additive silica was removed and the food-grade erythritol was adjusted to 30.0 wt%. This change occurred in the low-humidity tableting dry matrix and finished product formulation steps; other conditions remained the same: 30.0 wt% prebiotic vitrified matrix protecting live bacteria particles, 40.0 wt% food-grade starch, and 1.8 × 10⁻⁶ live bacteria count of *Lactobacillus plantarum* freeze-dried powder in the finished product. 10 The prebiotic vitrified matrix to lyophilized powder mass ratio was 2:1, the protected live bacteria particle D50 was 80 μm, and the protected live bacteria particle aw was 0.05. The mixing parameters were: A3 mixing temperature 15℃, relative humidity 5%, absolute pressure 0.09 MPa, mixing time 5 min; A4 water spraying 0.5 parts by mass, granulation temperature 20℃, granulation time 5 min; A5 drying temperature 25℃, drying time 0.5 h; S2 mixing temperature 15℃, relative humidity 5%, mixing time 8 min; S3 tableting force 3 kN, turntable speed 10 rpm, tablet exit temperature 20℃; S4 oxygen content 0.1 vol%, single tablet mass 0.6 g. This comparative example was used to investigate the synergistic relationship between prebiotic vitrified matrix protection and low-humidity tableting dry matrix flow-aiding shaping.

[0090] Characterization and performance testing: The viable cell count, viable cell retention rate after tableting, and viable cell retention rate after storage were determined for tablets from Examples 1–4 and Comparative Examples 1–9 to evaluate the effects of low humidity protection and tableting packaging conditions on viable cell preservation. Lactic acid bacteria counting was performed according to the corresponding counting method in GB4789.35-2023; bifidobacteria counting was performed according to the relevant method in GB4789.34-2016. After pulverizing the samples, homogenates were prepared, and the viable cell counts of lactic acid bacteria, bifidobacteria, and total viable cells were recorded, with n≥3. Data fields included factory viable cell count, viable cell retention rate after tableting, and viable cell retention rate after storage, in CFU / tablet and %. The viable cell retention rate after storage in Table 1 is uniformly listed based on the results after 3 months of sealed, light-protected storage at 25°C. Storage data for 6 months or 12 months, separately recorded in each example, were used for extended storage evaluation of the corresponding examples.

[0091] The hardness, friability, and disintegration time of tablets from Examples 1–4 and Comparative Examples 1–9 were measured to evaluate the effects of the dry matrix and compression force on the structural integrity of the tablets under low-humidity compression. Hardness was measured using a tablet hardness tester to determine the tablet breaking force; friability was calculated as the mass loss rate after treatment at a specified rotation speed; and disintegration time was recorded as the time it took for the tablet to completely disintegrate in an aqueous medium at 37°C. At least six tablets were measured for each sample, and the mean and standard deviation were calculated. The tablet hardness, friability, and disintegration time were obtained experimentally, expressed in N, wt%, and min. Moderate hardness and low friability indicate a more stable structure.

[0092] Moisture content and water activity (aw) were determined for prebiotic vitrified matrix powder, prebiotic vitrified matrix protected live bacteria granules, low-humidity tableting mixtures, and tablets. The aim was to evaluate whether the low-humidity release protocol was consistently applied throughout the pre-drying, granulation, mixing, tableting, and packaging steps. Moisture content was measured using the loss on drying method, and water activity was recorded using a water activity meter after the readings stabilized in a closed measuring chamber. For each batch of samples, n≥3, the average moisture content, standard deviation of moisture content, average aw, and standard deviation of aw were obtained, in units of wt% and dimensionless. Lower aw generally indicates better low-humidity stability of live bacteria.

[0093] The D50 and surface coverage of the vitrified prebiotic matrix protecting live bacteria particles and the corresponding live bacteria input materials in the comparative example were determined to evaluate the coverage and particle size control of the prebiotic vitrified matrix on the surface of the freeze-dried powder of the microbial preparation for food processing. D50 was analyzed using laser diffraction particle size analysis. Samples were taken under low humidity conditions of 5–25% relative humidity and dispersed within the same relative humidity range before volume distribution was measured. Surface coverage was identified using microscopic image area recognition, counting at least 100 particles, and calculated as the ratio of the covered area to the sum of the covered area and the visible area of ​​the freeze-dried powder's outer surface. Data fields are D50 and surface coverage, in μm and %.

[0094] Differential scanning calorimetry (DSC) was used to test the vitrified matrix powder of pre-dried prebiotics to evaluate the relationship between the vitrification state and storage temperature (25–30 °C). Samples with a moisture content of 0.3–4.0 wt% and an alumina (aw) of 0.03–0.18 were taken and subjected to temperature scanning in a sealed sample pan. The initial Tg temperature, midpoint Tg temperature, and final Tg temperature were recorded and compared with the storage temperature. The initial Tg temperature, midpoint Tg temperature, and final Tg temperature obtained from the experiment, in °C, were used as characterization and quality control data.

[0095] Inter-batch consistency evaluation was conducted on three batches of prebiotic vitrified matrix-protected live bacteria granules and three batches of high-viable-bacteria probiotic nutritional tablets to confirm the production stability of D50, water activity (aw), and viable bacteria retention rate after tableting. Samples from each batch were taken and tested for D50, water activity (aw), and viable bacteria retention rate after tableting. The average values ​​of the three batches were used as the calculation object, and the inter-batch coefficient of variation was calculated by dividing the standard deviation of the batch average by the arithmetic mean of the batch average and then multiplying by 100%. The inter-batch coefficients of variation for D50, aw, and viable bacteria retention rate after tableting were obtained experimentally, in percentages (%).

[0096] To verify the effectiveness of this invention in simultaneously ensuring tablet structural integrity, viable bacteria retention, processing flowability, and storage stability in high-live-bacteria probiotic nutritional tablets, a systematic evaluation was conducted on factors such as the content of protected viable bacteria particles, the proportion of prebiotic vitrified matrix, compression force, water activity, particle structure, tablet mechanical properties, and storage stability. The results indicate that this invention does not simply increase tablet hardness or solely pursue higher viable bacteria content. Instead, it achieves a good balance between viable bacteria protection, particle support, flowability, and storage stability through the synergistic matching of low-water-activity vitrified protective particles and a low-moisture compression system.

[0097] Figure 1 This diagram illustrates the effect of the prebiotic vitrified matrix content on the viability retention rate and tablet hardness after compression. Based on the fundamental process of Example 1, the prebiotic vitrified matrix to lyophilized powder mass ratio was fixed at 2:1, the compression force at 3 kN, and the tablet water activity (aw) at approximately 0.05. Only the content of the vitrified matrix particles was varied to 20, 30, 40, 50, 60, 70, and 80 wt%. The results show that when the vitrified matrix particle content was 30 wt%, the viability retention rate after compression was approximately 96%, and the tablet hardness was approximately 30 N. As the vitrified matrix particle content continued to increase, although the tablet hardness improved, the viability retention rate decreased, indicating that more vitrified matrix particles are not necessarily more beneficial. An appropriate amount of vitrified matrix particles can form effective viable cell carrying units in the tablet, while avoiding increased cell damage due to high viable cell particle content participating in compaction. This preliminarily demonstrates that this method achieves an adjustable balance between high viable cell loading and tablet forming strength.

[0098] Based on the determination of the content of protective live bacteria particles, the ratio between the vitrified matrix and the lyophilized powder was further investigated. Figure 2This diagram illustrates the effect of the prebiotic vitrification matrix to lyophilized powder mass ratio on the viable bacteria retention rate and tablet hardness after compression. Using Example 1 as a baseline, the content of protected viable bacteria particles was fixed at 30 wt%, the compression force at 3 kN, and the tablet water activity (aw) at approximately 0.05. Only the mass ratio of prebiotic vitrification matrix to lyophilized powder was varied to 1:1, 2:1, 5:1, 10:1, 15:1, 20:1, and 25:1. The results show that when the mass ratio is between 2:1 and 10:1, the viable bacteria retention rate after compression remains above approximately 95%, and the tablet hardness increases from approximately 30 N to approximately 52 N. This indicates that an appropriate amount of prebiotic vitrification matrix can improve the buffering and isolation effect of the lyophilized bacterial powder surface and contribute to the tablet hardness. When the mass ratio is further increased to 20:1 or 25:1, the viable bacteria retention rate decreases significantly, suggesting that excessive vitrification matrix may increase particle densification or change the compression force transmission method, which is detrimental to viable bacteria protection. Therefore, a proper ratio needs to be maintained between the prebiotic vitrified matrix and the lyophilized powder in order to achieve both surface protection and tablet compatibility.

[0099] Once the composition ratio is determined, the compression force is a key process parameter that affects the integrity of the tablet structure and the degree of damage to viable bacteria. Figure 3 This diagram illustrates the effect of compression force on the viable bacteria retention rate and tablet hardness after compression. Using Example 1 as a baseline, the content of protected viable bacteria particles was fixed at 30 wt%, the prebiotic vitrified matrix to lyophilized powder mass ratio was 2:1, and the tablet water activity (aw) was approximately 0.05. Only the compression force was varied to 2, 3, 5, 7, 9, 12, and 15 kN. The results show that as the compression force increased from 2 kN to 12 kN, the tablet hardness increased from approximately 18 N to approximately 118 N, but the viable bacteria retention rate after compression decreased from approximately 98% to approximately 80%. This indicates that while simply increasing the compression force can enhance the mechanical strength of the tablet, it significantly exacerbates compaction damage. In Example 1, with a compression force of approximately 3 kN, the tablet hardness was approximately 30 N, and the viable bacteria retention rate after compression was approximately 96%. This satisfies both the tablet forming and basic transport requirements and avoids excessive damage to the viable bacteria caused by high compaction conditions, thus demonstrating the synergistic advantages between low to medium compression force and the protected particle system.

[0100] Water activity directly affects the vitrification state and long-term storage stability of probiotic frozen stem cells, and is the core control factor in the low-humidity tableting system of this invention. Figure 4This diagram illustrates the effect of tablet water activity (aw) on viable cell retention after tableting and viable cell retention after 3 months of storage. Using Example 1 as a baseline, the content of protective viable bacteria particles was fixed at 30 wt%, the ratio of prebiotic vitrified matrix to lyophilized powder was 2:1, and the tableting force was 3 kN. Only the tablet water activity (aw) was varied to 0.03, 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30. The results show that when aw is approximately 0.05, the viable cell retention after tableting is approximately 96%, and the viable cell retention after 3 months of storage is approximately 95%. However, when aw increases to 0.25 and 0.30, the viable cell retention after 3 months of storage decreases to approximately 62% and 48%, respectively. This indicates that increased water activity weakens the vitrified protective state and promotes inactivation during storage. Maintaining a low system aw significantly reduces the risk of moisture absorption and inactivation, thus maintaining a high viable cell state after tableting.

[0101] To further explain the underlying reasons for the protective effect of low water activity, the thermal behavior of different samples was analyzed. Figure 5 The DSC heat flow-temperature curves for Examples 1, 2, and 4 are shown. By comparing the heat flow changes of different samples in the range of 0–80℃, the glass transition and moisture-related thermal effects were observed. The results show that the heat flow curve of Example 1 is more gradual overall, and the Tg-related transition temperature is higher than that of the comparative sample. This indicates that the prebiotic vitrification matrix in Example 1 forms a more stable glassy protective environment for the freeze-dried bacterial powder, and the system is less affected by moisture disturbance. Figure 6 The graphs show the relationship between the midpoint Tg temperature and water activity (aw) for Examples 1, 2, and 4. The results show that the midpoint Tg temperature for Example 1 is approximately 43°C when aw is approximately 0.05; for Comparative Example 2, it is approximately 34°C when aw is approximately 0.06; and for Comparative Example 4, it is approximately 22°C when aw is approximately 0.30. The higher midpoint Tg temperature indicates that Example 1 is more likely to maintain a glassy or high-viscosity protective state under normal storage temperatures, thereby reducing the risk of molecular migration, water-induced inactivation, and cell membrane structural disturbance. Therefore, it is evident that the low water activity control and the prebiotic vitrification matrix in this invention do not function in isolation, but rather together form the basis for improved storage stability.

[0102] In addition to thermal stability, the particle size distribution and surface coverage of the live bacteria input material directly affect the mixing uniformity, flowability, tableting force transfer, and the external barrier effect of the live bacteria. Figure 7The particle size differential volume distribution diagrams of the live bacteria input materials for Examples 1, 3, and 8 are used to characterize the particle size concentration and distribution uniformity after particle preparation. The results show that the main peak of the particle size distribution in Example 1 is concentrated around approximately 80 μm and has a narrow distribution; the main peak of Comparative Example 3 is biased towards the smaller particle size region, while Comparative Example 8 exhibits a wider or multi-peak distribution. These results indicate that Example 1 can form protective live bacteria particles with a moderate and concentrated particle size distribution, which is beneficial for their uniform dispersion in a low-humidity tableting system composed of food-grade starch, food-grade erythritol, and silica, and reduces compression damage caused by localized enrichment. Figure 8 The cumulative volumetric particle size distribution of the live bacteria input materials for Examples 1, 3, and 8 is shown. Further analysis reveals that the cumulative curve for Example 1 is smoother and the rising range is concentrated, while the cumulative curve for Comparative Example 8 has a larger span, indicating a significant mixture of small and large particles in its particle system. The differential and cumulative distribution results show that the particle system formed by this scheme has better particle size controllability, which helps improve processing flowability and the consistency of the tablet's internal structure.

[0103] Based on particle size distribution, the degree to which the protective matrix covers the surface of the live bacteria particles further determines whether the live bacteria can avoid direct contact with excipients and external moisture during tableting. Figure 9 The original scatter plot and mean ± SD of the surface coverage of Examples 1, 3, and 8 are used to compare the degree of coating of the protective matrix on the surface of the live bacteria particles. The results show that the mean surface coverage of Example 1 is approximately 60%, that of Comparative Example 3 is approximately 55%, and that of Comparative Example 8 is approximately 0%. Examples 1 and 3 both have a certain degree of coverage structure, while Comparative Example 8 hardly forms an effective coverage layer, indicating that after removing the prebiotic vitrification matrix protection, the lyophilized bacterial powder participates in the mixing and tableting in a more exposed or weakly protected state. The approximately 60% surface coverage in Example 1 can form a moderate barrier on the outside of the live bacteria, which reduces the direct shearing and compression between the live bacteria and the hard excipients during tableting, and also reduces the rapid migration of moisture to the surface of the bacteria during storage, thus providing a structural basis for the subsequent tablet performance and live bacteria stability.

[0104] After completing the evaluation of the particle protection structure, the tablet's forming properties, resistance to breakage, and disintegration release characteristics were further compared. Figure 10The original scatter plots and mean ± SD of tablet hardness for Examples 1, 5, 6, and 9 are used to evaluate the differences in tablet mechanical strength under different formulations or processing conditions. The results show that the tablet hardness of Example 1 is approximately 30 N, which is a moderate level sufficient for molding, packaging, and transportation. The hardness of Comparative Example 5 is approximately 138 N, significantly higher, indicating excessive tablet density and potentially increased compression damage to viable bacteria. The hardness of Comparative Examples 6 and 9 is approximately 22 N and 21 N, respectively, indicating low mechanical strength and insufficient tablet structural integrity. These results demonstrate that the present invention, through the combination of protective particles and a low-moisture tableting matrix, can achieve suitable hardness without employing excessively high tableting force or an overly dense structure.

[0105] Figure 11 The original scatter plots and mean ± SD of the friability of Examples 1, 5, 6, and 9 are used to evaluate the tablet's abrasion and breakage resistance. The results show that the friability of Example 1 is approximately 1.00 wt%, which is at a reasonable level; the friability of Comparative Example 5 is approximately 0.04 wt%, exhibiting strong abrasion resistance, but corresponding to its high hardness of approximately 138 N, indicating that its tablet structure is too dense, which is not conducive to maintaining viable bacteria; the friability of Comparative Examples 6 and 9 is approximately 1.42 wt% and 1.55 wt%, respectively, suggesting that their tablet structures are loose and more prone to breakage during transportation or use. Figure 12 The original scatter plots and mean ± SD of disintegration times for Examples 1, 5, 6, and 9 are used to evaluate the disintegration and release performance of tablets after administration. The results show that the disintegration time for Example 1 is approximately 3.0 min, while that for Comparative Examples 6 and 9 is approximately 2.7 min and 2.4 min, respectively, all exhibiting relatively rapid disintegration. However, the disintegration time for Comparative Example 5 is approximately 31.0 min, significantly prolonged, indicating that excessive hardness and over-compaction significantly affect tablet disintegration. Combined with... Figures 10 to 12 It can be seen that Example 1 did not sacrifice disintegration performance to achieve structural integrity, but rather formed a relatively balanced tablet quality characteristic between hardness, friability and disintegration time, thus addressing the problem that it is difficult to balance structural integrity and functional release in high viable bacteria tablets.

[0106] Based on the superior composition, structure, and tablet performance, the overall effectiveness of this scheme is ultimately evaluated by the viable cell retention rate during the manufacturing and storage processes. Figure 13The graphs showing the viable cell retention rates of Examples 1, 5, 7, and 8 are used to compare the viable cell retention after tableting and after 3 months of storage. The results show that the viable cell retention rate of Example 1 after tableting was approximately 96%, and remained at approximately 95% after 3 months of storage, indicating minimal viable cell loss. The viable cell retention rate of Comparative Example 5 was approximately 68% after tableting and approximately 65% ​​after storage, indicating that high compaction or high hardness conditions lead to significant tableting damage. The viable cell retention rate of Comparative Example 7 decreased from approximately 94% to approximately 58%, indicating that even with a high initial retention rate after tableting, significant inactivation can still occur if storage protection is insufficient. The viable cell retention rate of Comparative Example 8 decreased from approximately 62% to approximately 42%, indicating that without the protection of the prebiotic vitrification matrix, both processing damage and storage inactivation are significant. These results demonstrate that the present invention can simultaneously mitigate both compaction damage and moisture absorption inactivation, rather than only improving viable cell retention at a single stage.

[0107] Figure 14 The graphs show the correlation between water activity (aw) and viable cell retention rate after storage for Examples 1, 2, 8, and 4, used to evaluate the effect of moisture state on the viability of probiotics during storage. The results show that Example 1 achieved a viable cell retention rate of approximately 95% after storage when aw was approximately 0.05; Comparative Example 2 achieved approximately 70% when aw was approximately 0.06; Comparative Example 8 achieved approximately 42% when aw was approximately 0.08; and Comparative Example 4 achieved approximately 48% when aw was approximately 0.30. These results further illustrate that a lower aw is an important condition for maintaining viable cell stability, but a lower aw alone is insufficient to completely guarantee a high viable cell retention rate; it also requires the combined effect of vitrification matrix coverage, particle size control, and a low-moisture tableting excipient system. Example 1 exhibited a significantly higher viable cell retention rate after storage under similar or lower water activity conditions, indicating that the advantage of this invention stems from the synergy of low water activity, vitrification protection, and tablet structure matching, rather than a simple contribution from a single factor.

[0108] To verify the above results at the microscopic morphology level, the tablet cross-sectional structure of the final products of Example 1 and Comparative Example 8 was further observed. Figure 15 The image shows a comparison of the SEM morphology of the final product of Example 1 and the final product of Comparative Example 8, used to illustrate the distribution of prebiotic vitrified matrix-protected live bacteria particles in the tablet cross-section and their role in the formation of the live bacteria protection interface. Figure 15 Image a is a magnified SEM image of the final product of Example 1, showing that the protected live bacteria particles can form a stable contact interface with the tableting matrix composed of food-grade starch, food-grade erythritol and silica, and are embedded inside the tablet, indicating that the protected particles can participate in the molding as independent live bacteria carrier units in the tablet structure. Figure 15b is a mid-magnification SEM image of the final product of Comparative Example 8, showing the local structure after the freeze-dried bacterial powder and excipient matrix are directly mixed. The lack of a pre-constructed embedding interface suggests that the live bacteria are more susceptible to the effects of excipient friction, shearing and compaction during tableting. Figure 15 c is a high-magnification SEM image of the final product of Example 1, showing that the surface of the protected live bacteria particles has a vitrified matrix covering structure formed by inulin and food-grade resistant dextrin, with a surface coverage of about 60%. This morphological feature corresponds to the formation of a physical isolation layer and a low water activity microenvironment on the surface of the protected live bacteria particles. Figure 15 Image d is a high-magnification SEM image of the final product of Comparative Example 8, showing direct contact between the lyophilized live bacteria powder and the tableting excipients, with some interfaces lacking a pre-constructed protective layer. This morphological result corroborates the aforementioned results regarding particle size distribution, surface coverage, tablet mechanical properties, and live bacteria retention rate, indicating that this invention achieves a unified structure for both the live bacteria protection structure and the tablet forming structure by pre-constructing a prebiotic vitrified matrix to protect the live bacteria particles and combining it with a low-humidity tableting system.

[0109] In conclusion, Figures 1 to 15 A progressive verification relationship was established across multiple levels, including formulation ratio, compression force, water activity, thermal stability, particle size, surface coverage, tablet hardness, friability, disintegration time, viable cell retention rate, and microstructure. The results show that this invention can achieve suitable tablet hardness and a low risk of friability under high viable cell loading conditions, while maintaining high viable cell retention rates after compression and storage. This is based on the prebiotic vitrified matrix's low water activity surface protection of the freeze-dried bacterial powder, and the synergistic effect of the low-moisture compression system composed of food-grade starch, food-grade erythritol, and silica on particle support, flowability, and the forming process. Therefore, this invention effectively alleviates the contradiction between tablet structural integrity and viable cell retention rate, and between processing flowability and viable cell storage stability in high-viable-cell probiotic tablets.

[0110] Table 1 Performance of Examples and Comparative Examples As can be seen from the performance of the examples and comparative examples in Table 1, Examples 1–4 show a relatively balanced trend in terms of viable bacteria retention, tablet hardness, friability, particle coverage, and low water activity control. In the conventional comparative examples, reducing the content of protective viable bacteria particles, changing the ratio of matrix to lyophilized powder, deviating from the particle size, increasing particle size alumina (aw), excessively increasing the compression force, reducing the food additive silica, or increasing the sealed oxygen content all worsen at least one of the following indicators: viable bacteria retention, tablet structure, or storage stability. The synergistic effects of Comparative Examples 8 and 9 show that when the prebiotic vitrified matrix surface protection is lacking or the low-moisture compression dry matrix flow-forming unit is weakened, it is difficult to maintain viable bacteria retention and tablet integrity simultaneously, indicating that the data trend is consistent with the technical logic of balancing tablet structural integrity and viable bacteria stability.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that any equivalent structural transformations made under the concept of the present invention and using the contents of the specification and drawings of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A probiotic nutritional tablet with high live bacteria count, characterized in that, Based on a total mass of 100 wt% of the finished high-live-bacteria probiotic nutritional tablets, the product is composed of the following components, and the sum of the contents of each component is 100 wt%: a. Prebiotic vitrified matrix protects live bacteria particles 30–70 wt%; b. Food-grade starch 10–40 wt%; c. Food-grade erythritol 5–30 wt%; d. Food additive silicon dioxide 0.2–1.0 wt%; The prebiotic vitrified matrix-protected live bacteria particles include freeze-dried microbial preparations for food processing and a prebiotic vitrified matrix. The mass ratio of the prebiotic vitrified matrix to the freeze-dried powder of the food processing microbial culture preparation is 2:1 to 20:

1. The prebiotic vitrified matrix protects the live bacteria particles with a D50 of 80–250 μm and a water activity (aw) of 0.05–0.

20. The high-live-bacteria probiotic nutritional tablet has a water activity (aw) of 0.05–0.25, and the number of live bacteria per tablet at the time of manufacture is 1 × 10⁻⁶. 9 –1×10 11 CFU.

2. The high-live-bacteria probiotic nutritional tablet according to claim 1, characterized in that, The freeze-dried microbial preparation for food processing contains one or more live bacteria selected from Lactobacillus plantarum, Lactobacillus rhamnosus, Bifidobacterium animalis subsp. lactis, and Lactobacillus acidophilus. The prebiotic vitrified matrix comprises inulin and food-grade resistant dextrin, or comprises inulin, food-grade resistant dextrin and D-trehalose dihydrate, wherein the D-trehalose dihydrate accounts for 1–20 wt% of the total mass of the prebiotic vitrified matrix; the prebiotic vitrified matrix is ​​distributed on the surface of the freeze-dried powder of the food processing microbial preparation, and simultaneously serves as the prebiotic and dietary fiber components in the high-live-bacteria probiotic nutritional tablets.

3. The high-live-bacteria probiotic nutritional tablet according to claim 1, characterized in that, The prebiotic vitrified matrix-protected live bacteria particles are prepared through the following steps: A1. Provide freeze-dried microbial preparations for food processing; A2. Provides a prebiotic vitrified matrix powder, wherein the prebiotic vitrified matrix powder is composed of 60–95 wt% inulin and 5–40 wt% food-grade resistant dextrin, and the sum of the contents of inulin and food-grade resistant dextrin is 100 wt%, all percentages are based on the total mass of the prebiotic vitrified matrix powder, and the prebiotic vitrified matrix powder is obtained by mixing inulin and food-grade resistant dextrin and pre-drying; A3. Mix 100 parts by weight of the freeze-dried powder of the microbial inoculum preparation for food processing with 200–2000 parts by weight of the prebiotic vitrified matrix powder, or mix 100 parts by weight of the freeze-dried powder of the microbial inoculum preparation for food processing with 200–2000 parts by weight of a prebiotic vitrified matrix containing the prebiotic vitrified matrix powder and D-trehalose dihydrate, and mix for 5–20 min at a temperature of 15–25°C, a relative humidity of 5–25%, and an absolute pressure of 0.09–0.11 MPa to obtain a low-humidity premix. A4. Spray 0.5–8.0 parts by weight of deionized water for food production into the low-moisture premix, and granulate for 5–25 minutes at a temperature of 20–32°C, a relative humidity of 5–25%, and an absolute pressure of 0.09–0.11 MPa to obtain wet granules. A5. The wet particles are dried at a temperature of 25–35℃, an absolute pressure of 0.09–0.11 MPa, and a drying time of 0.5–3.0 h, so that the water activity aw of the particles reaches 0.05–0.20; A6. Granulate the particles obtained in step A5 to obtain particles with a D50 of 80–250 μm, a prebiotic vitrification matrix surface coverage of 60–95%, and a viable bacterial count of 1 × 10⁻⁶ before tableting. 9 –1×10 11 CFU / g of prebiotic vitrified matrix protects live bacteria particles.

4. The high-live-bacteria probiotic nutritional tablet according to claim 3, characterized in that, The viable count of the freeze-dried microbial preparation for food processing described in step A1 is 1 × 10⁻⁶. 10 –5×10 11 The prebiotic vitrified matrix powder in step A2 has a moisture content of 0.3–4.0 wt%, a water activity of 0.03–0.18, and a D50 of 20–180 μm.

5. The high-live-bacteria probiotic nutritional tablet according to claim 3, characterized in that, The prebiotic vitrified matrix powder mentioned in step A2 is prepared through the following steps: A21. Mix 60–95 parts by weight of inulin with 5–40 parts by weight of food-grade resistant dextrin for 8–25 min to obtain a prebiotic mixed powder; A22. The prebiotic mixed powder is pre-dried at a temperature of 30–45℃ and an absolute pressure of 0.09–0.11MPa for 1–6 hours. When the moisture content of the prebiotic mixed powder is 0.3–4.0wt% and the water activity aw is 0.03–0.18, the prebiotic vitrified matrix powder is obtained, and the D50 of the obtained prebiotic vitrified matrix powder is 20–180μm. A23. The prebiotic vitrified matrix powder is mixed with the freeze-dried powder of the microbial inoculum preparation for food processing in step A3, and distributed on the surface of the freeze-dried powder of the microbial inoculum preparation for food processing during the granulation process in step A4.

6. The high-live-bacteria probiotic nutritional tablet according to claim 1, characterized in that, The food-grade starch, the food-grade erythritol, and the food additive silica form a low-moisture tableting dry matrix, which is prepared through the following steps: C1. Mix food-grade starch and food-grade erythritol according to their corresponding mass ratios in the finished high-live-bacteria probiotic nutritional tablets for 8–25 min; C2. Add food additive silicon dioxide to the mixture from step C1 according to the corresponding mass fraction of food additive silicon dioxide in the finished product of the high live bacteria probiotic nutritional tablets, and continue mixing for 3–12 min to obtain a low-moisture compressed dry matrix. C3. The mixing process is carried out at a temperature of 15–25°C, a relative humidity of 5–25%, and an absolute pressure of 0.09–0.11 MPa; C4. The moisture content of the dry matrix of the low-moisture tablet is 0.3–5.0 wt%, and the water activity (aw) is 0.03–0.

20.

7. A method for preparing a high-live-bacteria probiotic nutritional tablet as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Provides pre-prepared prebiotic vitrified matrix to protect live bacteria particles and a low-moisture tableting dry matrix formed from food-grade starch, food-grade erythritol and food additive silica; S2. Mix the prebiotic vitrified matrix protected live bacteria particles and the low-humidity tableting dry matrix at a temperature of 15–25°C and a relative humidity of 5–25% for 8–25 minutes to obtain a low-humidity tableting mixture; S3. The low-moisture tableting mixture is compressed into tablets under a tableting force of 3–12 kN and a tableting temperature of 20–35°C to obtain tablets; S4. The tablets are sealed in a food-grade nitrogen atmosphere with an oxygen content of 0.1–5.0 vol% to obtain the high-live-bacteria probiotic nutritional tablets.

8. The preparation method according to claim 7, characterized in that, The moisture content of the low-moisture tableting mixture obtained in step S2 is 0.5–3.5 wt%, the water activity aw is 0.05–0.23, and the bulk density is 0.30–0.90 g / mL; the single tablet weight of the tablets mentioned in step S3 is 0.6–1.8 g, and the water activity aw of the tablets after compression is 0.05–0.

25.

9. The preparation method according to claim 7, characterized in that, In step S4, the water vapor permeability of the sealed packaging is 0.01–1.00 g / (m³). 2 •d) The relative humidity inside the packaging is 1–20%.

10. The preparation method according to claim 7, characterized in that, The inter-batch coefficient of variation (COP) for D50 of the three batches of prebiotic vitrified matrix-protected live bacteria granules provided in step S1 was 2–15%, and the inter-batch coefficient of variation for water activity (aw) of the three batches was 1–12%. The inter-batch coefficient of variation for the live bacteria retention rate of the high-live bacteria probiotic nutritional tablets prepared using the prebiotic vitrified matrix-protected live bacteria granules provided in step S1 was 3–20% after tableting.

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