Modified children's dietary fiber based on microcapsule embedding and ultra-micro homogenization emulsification and preparation method thereof

Abstract

This invention discloses a modified children's dietary fiber based on microcapsule encapsulation and ultra-micro homogenization emulsification and its preparation method, which is prepared according to the following steps: (1) Raw material pretreatment: plant fiber is crushed; (2) Enzymatic modification: the fiber powder is prepared into a fiber suspension slurry, cellulase is added for enzymatic hydrolysis, and the modified fiber slurry is obtained after enzyme inactivation and cooling; (3) Composite wall material preparation: maltodextrin or whey protein and gum arabic are weighed, dissolved in deionized water, and natural antioxidants are added; (4) Homogenization emulsification and microcapsule encapsulation: the modified fiber slurry obtained in step (2) is dispersed in the wall material solution in step (3) as the core material, and homogenized using a two-stage gradient high pressure treatment. After homogenization, the product is obtained by spray drying or fluidized bed encapsulation and solidification. Through nanoscale reshaping and directional encapsulation, the rough taste of dietary fiber is completely eliminated, unpleasant flavors are masked, and natural antioxidants are used to improve the stability and intestinal bioavailability of the product.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, specifically to a modified children's dietary fiber based on microencapsulation and ultra-micro homogenization emulsification and its preparation method. Background Technology

[0002] Dietary fiber is the seventh essential nutrient for the human body, possessing various physiological functions such as regulating gut microbiota, promoting intestinal peristalsis, absorbing intestinal fats and bile acids, and improving constipation. It plays a vital role in children's intestinal development, immunity enhancement, and dietary optimization. Natural plant-based dietary fiber is widely available and highly safe, making it a preferred raw material for children's functional foods.

[0003] However, existing natural plant dietary fibers have many shortcomings that severely limit their large-scale application in children's food: First, the original fiber particles are large, with a rough and gritty texture, which does not meet children's oral sensory preferences and has low acceptance; Second, natural fiber raw materials such as bamboo shoots, wheat bran, and Jerusalem artichokes have a bitter taste that is difficult to completely remove through conventional processing; Third, insoluble dietary fibers have poor water solubility, are prone to separation and sedimentation when mixed with water, and have poor product stability; Fourth, ordinary dietary fibers have weak structural stability and are easily decomposed and inactivated in the strong acidic environment of children's stomachs, making it impossible for them to effectively reach the intestines to exert their beneficial effects, resulting in low functional utilization; Fifth, conventional modified dietary fiber products have short shelf lives, are prone to oxidative browning, and mostly rely on artificial additives for preservation, which does not meet the high safety requirements of children's food.

[0004] Current technologies mostly use a single ultra-fine grinding or single enzymatic hydrolysis method to modify dietary fiber, resulting in a single modification effect that cannot simultaneously solve multiple problems such as taste, flavor, stability, and targeted release. Conventional microcapsule encapsulation process parameters are broad and the formulas are simple, without any adaptation design for the digestive physiology of children. They can only achieve simple encapsulation and cannot achieve the effects of gastric acid lock-in and precise intestinal sustained release. Moreover, they generally have the defects of low encapsulation rate and no obvious functional gain. Summary of the Invention

[0005] To address the aforementioned technical problems, the present invention aims to provide a modified children's dietary fiber based on microencapsulation and ultra-micro homogenized emulsification, and its preparation method. Through nanoscale reshaping and directional encapsulation, the rough texture of the dietary fiber is completely eliminated, unpleasant flavors are masked, and natural antioxidants are used to improve product stability and intestinal bioavailability.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing modified children's dietary fiber based on microencapsulation and ultra-micro homogenization emulsification, characterized by preparation according to the following steps:

[0007] (1) Raw material pretreatment: Select plant fiber raw materials, wash and dry them, and then use low temperature airflow to pulverize them into ultrafine powder with a particle size of 0.1-5μm.

[0008] (2) Enzymatic hydrolysis modification: The ultrafine fiber powder is prepared into a fiber suspension slurry, cellulase is added for enzymatic hydrolysis, and the modified fiber slurry is obtained after enzyme inactivation and cooling.

[0009] (3) Preparation of composite wall material: Weigh maltodextrin or whey protein and gum arabic, dissolve them in deionized water to obtain a uniform composite wall material solution, and add natural antioxidants to the composite wall material solution;

[0010] (4) Homogenization and microencapsulation: The modified fiber slurry obtained in step (2) is dispersed in the wall material solution in step (3) as the core material, and the core-to-wall mass ratio is controlled to be 1:3 to 1:5. Two-stage gradient high-pressure homogenization is adopted, with a first-stage homogenization pressure of 20 to 40 MPa, a second-stage homogenization pressure of 50 to 80 MPa, and a homogenization temperature of 45 to 60 °C. After homogenization, microencapsulated dietary fiber powder is obtained by spray drying or fluidized bed encapsulation and solidification.

[0011] In the above scheme: in step (1), the plant fiber raw material is one or a combination of bamboo shoots, oats, Jerusalem artichokes, and wheat bran, or a combination of bamboo shoots, oats, Jerusalem artichokes, wheat bran and fructooligosaccharides.

[0012] In the above scheme: the amount of cellulase added is 0.4% to 0.6% of the dry weight of plant fiber, the enzymatic hydrolysis temperature is 35 to 40℃, the enzymatic hydrolysis time is 1.5 to 2.5 h, the enzyme inactivation temperature is 85 to 95℃, and the enzyme inactivation time is 8 to 12 min.

[0013] In the above scheme, the mass ratio of maltodextrin or whey protein to gum arabic is 3:1.

[0014] In the above scheme, the natural antioxidants are tea polyphenols, grape seed extract or lemongrass essential oil, and the amount added is 0.5% to 3.0% of the total mass of the wall material.

[0015] In the above scheme: in step (4), the spray drying process parameters are: inlet air temperature 170~190℃, outlet air temperature 80~90℃; fluidized bed embedding and solidification temperature is 35~45℃.

[0016] In the above scheme: the microencapsulated dietary fiber powder is compounded with natural sweeteners, natural flavorings, and food stabilizers, and then mixed, homogenized, or extruded and expanded to produce children's special dietary fiber gummies or instant beverage powder.

[0017] The modified children's dietary fiber prepared by the method described above based on microencapsulation and ultra-micro homogenization emulsification is a modified children's dietary fiber based on microencapsulation and ultra-micro homogenization emulsification.

[0018] This invention utilizes low-temperature airflow ultra-fine pulverization to control particle size to the micron level, eliminating the rough, granular feel of fibers and completely eliminating the "gritty" sensation. Enzymatic hydrolysis with cellulase enhances water solubility and improves flavor. The addition of natural antioxidants avoids chemical additives, ensuring food safety for children. Gradient two-stage high-pressure homogenization strengthens the interfacial bonding of the core and wall materials, significantly improving encapsulation uniformity and efficiency. The dense structure of the microcapsules enables activation in the gastric acid environment and targeted sustained release in the intestinal environment, maximizing the retention of the beneficial functions of dietary fiber.

[0019] This invention addresses the industry pain points of traditional plant-based dietary fibers—namely, their rough texture, strong bitterness, poor solubility, easy loss of activity in children's acidic stomach environments, and weak functional stability—through a synergistic effect of low-temperature airflow ultrafine pulverization to control particle size at the micron level, enzymatic debittering modification, natural plant-based compound preservation wall materials, gradient high-pressure homogenization emulsification, and microencapsulation and solidification processes. Unlike existing single-process stacking models, this invention forms a complete system specifically for modifying children's dietary fibers. Through the synergistic cooperation of each process step, multiple synergistic gains are achieved in optimizing the physical texture of the fiber, improving its properties, enhancing its structural stability, and targeting the release of its functions. Ultimately, this results in a highly palatable, safe, highly active, and highly stable functional food product specifically formulated for children. It can be flexibly used to prepare children's gummies and instant beverage powders.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. Significant advantages in taste and flavor: By pulverizing into micron-sized particles and enzymatic modification, the rough texture of fibers and the inherent bitterness of raw materials are eliminated from both physical and chemical levels. High palatability can be achieved without artificial sweeteners, which meets the oral sensory needs of children and increases children's acceptance by more than 90%.

[0022] 2. Safety meets children's food standards: It adopts a natural plant preservation and antioxidant system such as tea polyphenols and grape seed extract, which completely replaces traditional chemical preservatives and has a high level of food safety.

[0023] 3. Strong structural stability and high functional utilization: Through a gradient high-pressure homogenization process, the interfacial bonding force of the core and wall materials is strengthened, resulting in a dense and stable microcapsule structure that can resist the erosion of strong stomach acid in children. This achieves "gastric activation and targeted intestinal release," completely solving the industry pain points of traditional fiber-based products that suffer from gastric acid inactivation and low functional utilization. The encapsulation rate can reach 74%-88%, effectively preventing oxidative deterioration, extending shelf life, and leaving no chemical preservative residues. The microcapsule structure enables targeted release of active ingredients, with a release rate of >80% under simulated gastrointestinal fluid conditions, significantly enhancing intestinal regulatory function. Detailed Implementation

[0024] The present invention will be further described below with reference to embodiments.

[0025] Example 1

[0026] Children's microcapsule bamboo shoot dietary fiber gummies are prepared according to the following steps:

[0027] 1. Raw material pretreatment

[0028] Natural dried bamboo shoots free of mold and impurities are selected as raw materials. After rinsing with clean water to remove surface dust and impurities, they are dried in a low-temperature drying device until the moisture content is ≤8%. The dried bamboo shoot raw materials are then ultra-finely pulverized using a low-temperature airflow ultra-fine pulverizer, with the pulverization temperature controlled at ≤35℃ throughout the process to avoid high temperatures damaging the prebiotic activity and nutritional structure of the bamboo shoot dietary fiber. Finally, the pulverized and sieved materials yield bamboo shoot ultra-fine fiber powder with a particle size of 5μm, completely eliminating the rough and granular feel of traditional bamboo shoot fiber and laying the foundation for subsequent homogenization, emulsification, and encapsulation processes.

[0029] 2. Enzymatic hydrolysis modification treatment

[0030] 100 kg of bamboo shoot ultrafine fiber powder was added to deionized water to prepare a fiber suspension with a mass fraction of 8%. After stirring evenly, food-grade cellulase (0.6% of the dry weight of the fiber) was added to the suspension. The enzymatic hydrolysis was controlled at a constant temperature of 35-40℃ and carried out under low-speed stirring for 2 hours. Through the specific degradation effect of cellulase, the water solubility of dietary fiber was significantly improved, and the bitter taste was reduced, while prebiotic activity and intestinal regulatory function were fully preserved. After enzymatic hydrolysis, the enzyme was inactivated by heating in a water bath at 85-95℃ for 10 minutes to terminate the enzymatic hydrolysis reaction and avoid over-hydrolysis leading to the loss of functional components. After cooling, the modified bamboo shoot fiber slurry was obtained.

[0031] 3. Preparation of composite wall materials

[0032] 300 kg of maltodextrin and 100 kg of gum arabic were accurately weighed as the composite microcapsule wall material. The two wall material raw materials were uniformly dispersed in constant-temperature deionized water and stirred at low speed until completely dissolved, preparing a uniform and transparent wall material solution. 5 kg of food-grade tea polyphenols were added to the wall material solution as a natural biological preservative and antioxidant active ingredient. Without affecting the product's taste and safety, this achieves the dual effects of fiber activity protection and product antibacterial preservation, replacing traditional chemical preservatives to meet children's food safety standards.

[0033] 4. Staged high-pressure homogenization emulsification and microcapsule pre-encapsulation

[0034] The modified bamboo shoot fiber slurry (core material) prepared in step 2 is slowly added to the composite wall material solution in step 3, with the mass ratio of core material to wall material precisely controlled at 1:4. This ratio balances encapsulation stability and dietary fiber content in the product. After the mixture is thoroughly stirred, it is sent to a high-pressure homogenizer for two-stage homogenization and emulsification treatment. The process parameters are strictly controlled: the first-stage homogenization pressure is 30 MPa to achieve initial dispersion and fusion of the core material and wall material; the second-stage homogenization pressure is 60 MPa to further refine particles and strengthen interfacial bonding; and the homogenization temperature is controlled at 45-60℃ throughout the process. Multi-stage gradient homogenization can completely eliminate material agglomeration, forming a uniform, stable, and non-layered microemulsion system, which significantly improves the subsequent microcapsule encapsulation rate and structural stability.

[0035] 5. Preparation of microcapsule fiber powder by spray drying and curing

[0036] The homogenized and stable microemulsion mixture is fed into a spray dryer for curing and powdering. Strict control of drying process parameters—inlet air temperature 170-190℃ and outlet air temperature 80-90℃—ensures rapid curing of the wall material structure while preventing high-temperature burning that could damage the activity of dietary fiber and the antioxidant components of tea polyphenols. After drying, the powder is collected and passed through an 80-mesh standard sieve to remove any small amount of agglomerated particles, resulting in a free-flowing, clumpy, and smooth-tasting microencapsulated bamboo shoot dietary fiber powder.

[0037] Encapsulation performance: The microcapsule encapsulation rate of this embodiment can reach 82%, with complete encapsulation structure and few defects; Solubility performance: When mixed with room temperature warm water, the powder can be completely dissolved, and the solution is clear and transparent, without clumping, precipitation, or layering, and its instant solubility far exceeds that of traditional dietary fiber solid beverages.

[0038] Targeted release performance: Verified through in vitro simulated human digestion experiments, the product maintains the integrity of the microcapsule wall structure in the strong acidic environment of a child's stomach (pH=1.5~2.5), effectively protecting the internal prebiotic fibers from being decomposed and destroyed by stomach acid; after entering the weakly alkaline environment of the intestine, the wall material slowly dissolves and releases the fiber activity, with a release rate of >80%, achieving the exclusive effect of "keeping the product alive in the stomach and targeting the release in the intestine," perfectly adapting to the digestive physiological characteristics of children.

[0039] 6. Post-forming processing of children's gummies

[0040] Using microencapsulated bamboo shoot fiber powder as the core functional ingredient, 45% natural zero-calorie sweetener erythritol, 3% food-grade pectin (gel stabilizer), and 0.8% natural strawberry plant extract flavoring are added according to weight. After all ingredients are mixed evenly, they are processed through low-temperature extrusion, shaping, and drying to produce soft, chewy, sugar-free, artificial coloring-free, and artificial preservative-free functional dietary fiber gummies suitable for children to chew.

[0041] Sensory evaluation: The product has a smooth and delicate texture, without any roughness from fibrous particles, completely eliminating the bitterness and off-flavor of bamboo shoot fiber. It has a rich fruity aroma and moderate sweetness, making it highly acceptable to children. The overall sensory score is 9.2 / 10. In an in vitro simulated intestinal digestion experiment at 37℃, simulating the human intestinal environment, the dietary fiber bile acid adsorption capacity of this product can reach 7.9 mg / g. Compared to ordinary bamboo shoot dietary fiber that has not undergone ultra-fine grinding, enzymatic hydrolysis, and microencapsulation, the functional activity is increased by 38.6%, significantly improving intestinal regulation and digestion promotion effects, demonstrating a clear functional gain.

[0042] Example 2: Children's Dietary Fiber Fortified Beverage Powder

[0043] 1. Ultrafine pretreatment of compound prebiotic raw materials

[0044] Inulin and fructooligosaccharides are mixed in a 2:1 mass ratio (the combination of the two can synergistically regulate the intestinal flora, providing gentle probiotics without intestinal irritation). After dust removal, cleaning, and drying, the mixed raw materials are ultra-finely pulverized using a low-temperature airflow ultra-micro pulverizer, with the temperature controlled at ≤35℃ throughout the process. The final particle size is precisely controlled to 0.1 micrometers, improving the product's water solubility and solving the problems of sedimentation, layering, and cloudy taste in traditional dietary fiber beverages.

[0045] 2. Enzyme modification

[0046] 100 kg of a mixture of inulin and fructooligosaccharide powder (inulin to fructooligosaccharide mass ratio 2:1) was added to deionized water to prepare a fiber suspension slurry. After stirring evenly, food-grade cellulase at 0.4% of the dry weight of the fiber was added to the slurry. The enzymatic hydrolysis temperature was controlled at 35-40℃, and the slurry was subjected to directional enzymatic hydrolysis for 2 hours under low-speed stirring. After the enzymatic hydrolysis was completed, the enzyme was inactivated by heating in a water bath at 85-95℃ for 12 minutes.

[0047] 3. Preparation of composite wall materials

[0048] Weigh out 300kg of whey protein and 100kg of gum arabic to make a special composite wall material. Add 3% grape seed extract by weight of the total wall material as a natural antioxidant and preservative. It is mild and safe, meets children's food standards, and can effectively protect the activity of complex prebiotics and extend the product's shelf life.

[0049] 4. Low-temperature fluidized bed precision embedding process

[0050] The fiber slurry is dispersed in the compound wall material solution and stirred to form a homogeneous mixture. Low-temperature fluidized bed encapsulation technology is employed, with the encapsulation and curing temperature precisely controlled at 35-45℃. This low-temperature process maximizes the preservation of the bioactivity of inulin, fructooligosaccharides, and grape seed extract, avoiding the deactivation of functional components caused by high temperatures. Through fluidized bed dynamic film formation and encapsulation, the wall material uniformly coats the fiber core material, forming dense and stable microcapsule particles.

[0051] After encapsulation, the product is air-dried, sieved, and sterilized to obtain a dry, loose, and highly fluid compound dietary fiber beverage powder. No additional artificial additives are needed; it can be directly mixed with warm water and consumed, making it suitable for young children.

[0052] Encapsulation performance: The microcapsule encapsulation rate in this embodiment reaches 88%, with an intact encapsulation structure and few defects; Solubility performance: When mixed with room temperature warm water, the powder can be completely dissolved within 1 minute, and the solution is clear and transparent, without clumping, precipitation, or layering, with instant solubility far exceeding that of traditional dietary fiber solid beverages; Targeted release performance: Verified by in vitro simulated human digestion experiments, the product maintains the integrity of the microcapsule wall structure in the strong acidic environment of children's stomach (pH=1.5~2.5), which can effectively protect the internal prebiotic fibers from being decomposed and destroyed by stomach acid; after entering the weakly alkaline environment of the intestine, the wall material slowly dissolves and releases, with a fiber activity release rate of >85%, achieving the exclusive effect of "keeping alive in the stomach and targeted release in the intestine", perfectly adapting to the digestive physiological characteristics of children.

[0053] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing modified dietary fiber for children based on microcapsule embedding and ultra-micro homogenization emulsification, characterized in that, Prepare according to the following steps: (1) Raw material pretreatment: Select plant fiber raw materials, wash and dry them, and then use low temperature airflow to pulverize them into ultrafine powder with a particle size of 0.1-5μm. (2) Enzymatic hydrolysis modification: The ultrafine fiber powder is prepared into a fiber suspension slurry, cellulase is added for enzymatic hydrolysis, and the modified fiber slurry is obtained after enzyme inactivation and cooling. (3) Preparation of composite wall material: Weigh maltodextrin or whey protein and gum arabic, dissolve them in deionized water to obtain a uniform composite wall material solution, and add natural antioxidants to the composite wall material solution; (4) Homogenization and microencapsulation: The modified fiber slurry obtained in step (2) is dispersed in the wall material solution in step (3) as the core material, and the core-to-wall mass ratio is controlled to be 1:3 to 1:

5. Two-stage gradient high-pressure homogenization is adopted, with a first-stage homogenization pressure of 20 to 40 MPa, a second-stage homogenization pressure of 50 to 80 MPa, and a homogenization temperature of 45 to 60 °C. After homogenization, microencapsulated dietary fiber powder is obtained by spray drying or fluidized bed encapsulation and solidification.

2. The process for the preparation of modified dietary fibre for children based on microencapsulation and ultra-micro homogenization emulsification as claimed in claim 1, wherein: In step (1), the plant fiber raw material is one or a combination of bamboo shoots, oats, Jerusalem artichokes, and wheat bran, or a combination of bamboo shoots, oats, Jerusalem artichokes, wheat bran and fructooligosaccharides.

3. The method for preparing modified children's dietary fiber based on microencapsulation and ultra-micro homogenization emulsification according to claim 1, characterized in that: The amount of cellulase added is 0.4% to 0.6% of the dry weight of plant fiber. The enzymatic hydrolysis temperature is 35 to 40℃, the enzymatic hydrolysis time is 1.5 to 2.5 h, the enzyme inactivation temperature is 85 to 95℃, and the enzyme inactivation time is 8 to 12 min.

4. The method for preparing modified children's dietary fiber based on microencapsulation and ultra-micro homogenization emulsification according to any one of claims 1-3, characterized in that: The mass ratio of maltodextrin or whey protein to gum arabic is 3:

1.

5. The method for preparing modified children's dietary fiber based on microencapsulation and ultra-micro homogenization emulsification according to claim 4, characterized in that: Natural antioxidants include tea polyphenols, grape seed extract, or lemongrass essential oil, with an addition amount of 0.5% to 3.0% of the total mass of the wall material.

6. The method for preparing modified children's dietary fiber based on microencapsulation and ultra-micro homogenization emulsification according to claim 5, characterized in that: In step (4), the spray drying process parameters are: inlet air temperature 170~190℃, outlet air temperature 80~90℃; fluidized bed embedding and solidification temperature is 35~45℃.

7. The method for preparing modified children's dietary fiber based on microencapsulation and ultra-micro homogenization emulsification according to claim 1, characterized in that: The obtained microencapsulated dietary fiber powder is compounded with natural sweeteners, natural flavorings, and food stabilizers, and then processed through mixing and homogenization or extrusion puffing to produce children's special dietary fiber gummies or instant beverage powder.

8. The modified children's dietary fiber prepared by the method of any one of claims 1-7 based on microencapsulation and ultra-micro homogenization emulsification.