Precise nutrition delivery system based on nano-structure unit imitation building block type construction and preparation method and application of meal replacement product of precise nutrition delivery system

Abstract

The invention discloses a precise nutrition delivery system based on a nano-structure unit imitation building block type construction and a preparation method and application of a meal replacement product of the precise nutrition delivery system, and belongs to the technical field of functional food processing and nutrition delivery. According to the method, a core functional matrix with a stable multi-stage ordered structure, a stable three-dimensional network and an active ingredient synergistic release characteristic is constructed by precisely constructing a water-phase functional core and an oil-phase structural domain and carrying out controllable assembly and interface fusion according to an optimized ratio. Furthermore, maltodextrin, composite minerals, vitamins and other nutritional components are systematically introduced into the matrix, colloid scale integration and structure stabilization are achieved through efficient homogenization, and finally a delivery system with comprehensive nutrition and stable system is obtained. The system not only can be directly used as a liquid meal replacement, but also can be converted into solid instant powder through introduction of inulin and spray drying, and can be widely applied to multiple fields of nutritional meal replacement foods, sports nutritional supplements, dietary supplements and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of functional food processing and nutrition delivery, and specifically relates to a precise nutrition delivery system based on nano-structured unit blocks and a preparation method and application of a meal replacement product thereof. BACKGROUND

[0002] In recent years, nutrition meal replacement products have gained widespread attention in the domestic and foreign markets due to their high nutritional value and easy digestion, which can provide consumers with a meal or even multiple meals of dietary replacement options. Functional factors, as a class of ingredients with specific physiological activities, can bring many benefits to human functions. However, the chemical structure of such substances is generally unstable, which greatly limits their application in the food industry. At present, a large number of studies have focused on the construction of various delivery carriers to improve the stability and bioavailability of functional factors through carrier protection. Nanoparticles and nanoemulsions are two of them with excellent performance. In addition, the delivery carriers prepared based on natural biological macromolecules can also provide the body with the required energy. In addition to the above-mentioned nutrients, the further addition of other nutrients required by the body in the food system can also prepare a complex nutritional liquid beverage - a new product form, which not only accurately covers the various nutrients required by the human body, effectively avoids various health problems caused by unreasonable dietary structure, but also promotes the efficient absorption and utilization of nutritional substances in the human body.

[0003] However, the composition of the complex nutritional liquid beverage is relatively complex, which can easily cause protein denaturation and aggregation, product phase separation and other adverse phenomena. Analysis shows that such adverse phenomena are mostly caused by the interaction between the components of the product. In addition, after the functional factors are added to the system, they often interact with other components, thereby causing a series of quality problems (such as decreased stability and reduced nutritional value). The specific analysis is as follows: Patent (application number CN202411145544.7, publication number CN118985705A) discloses a liquid nutrition meal replacement weight loss food and a preparation method thereof. The core of the technical solution is to prepare a liquid nutrition meal replacement system by compounding resistant starch, Poria cocos extract and composite plant extract. However, the preparation process has a significant defect: a large amount of ethanol is used as a solvent or treatment medium in the preparation process of the composite resistant starch. The introduction of ethanol not only increases the complexity and cost of the production process, but more importantly, it may cause residual risks. For specific consumer groups with ethanol sensitivity or limited metabolic capacity, such as children, pregnant women, people with liver dysfunction or elderly people with underlying diseases, such products have clear eating restrictions and potential health risks, which greatly limit their application universality and market audience range.

[0004] Patent (application number CN202010506317.8, publication number CN111728003A) discloses "a kind of fat-reducing hypoglycemic crisp meal biscuits and its preparation method". Although this scheme provides the form of meal biscuits, its nutritional composition is relatively basic, and it fails to systematically integrate the various functional factors emphasized by modern nutrition. The more prominent technical shortcoming is that the added nutrients have not been subjected to any effective encapsulation or homeostasis treatment. During the baking preparation and subsequent storage of the biscuits, environmental factors such as heat, oxygen, and light can easily lead to the oxidative degradation and loss of biological activity of heat-sensitive nutrients (such as some vitamins and antioxidant components), i.e., the significant "inactivation phenomenon" occurs, making it difficult to ensure the nominal nutritional potency and actual intake effect of the product.

[0005] "Enhancing the stability of O / W emulsions by the interactions of casein / carboxymethyl chitosan and its application in whole nutrient emulsions" discusses the use of sodium caseinate and carboxymethyl chitosan to stabilize oil-in-water emulsions and their application in whole nutrient emulsions. Although this study has made progress in interfacial stabilization, the minimum particle size of the prepared emulsion still reaches the level of 12.98 ± 0.93 μm, which belongs to the micron scale category. Larger droplet size usually means a relatively small interfacial area, and the emulsion system is more unstable in kinetics, prone to gravitational separation, flocculation, and even demulsification during long-term storage, i.e., there is a risk of insufficient physical stability, which directly affects the shelf life of the product and the consumer experience.

[0006] Physicochemical characterization, sensory quality analysis, and shelf-life prediction during the storage of a total nutrient formula emulsion focuses on the physicochemical characterization and shelf-life prediction of total nutrient formula emulsion. The value of this work lies in providing a methodology reference for emulsion stability evaluation. However, the technical model has a fundamental limitation: the emulsion system constructed in this study does not perform any targeted micro-nano encapsulation or protective treatment on the functional active ingredients (such as unsaturated fatty acids, vitamins, and polyphenols). During storage, these exposed functional factors are continuously exposed to the aqueous environment and directly contact with dissolved oxygen and other substances, leading to rapid chemical degradation reactions such as hydrolysis and oxidation. This makes the shelf-life prediction model based on the continuous loss of active ingredients, failing to solve the core problem of long-term maintenance of functional factors.

[0007] Currently, there are numerous reports on functional factor encapsulation technology, but there are few reports on the preparation of composite nutritional meal replacement products using functional factor delivery carriers as the core substrate. At the same time, the existing commercially available nutritional meal replacement products are mostly simple physical mixing of various types of grain powder, and there are common problems such as single nutritional components and insufficient functional activity. Therefore, developing nutritional meal replacement products with comprehensive nutritional composition and high stability has become a key technical problem that needs to be solved by technical personnel in the relevant field. SUMMARY

[0008] The present application provides a precise nutrition delivery system based on nano-structured unit and a preparation method of meal replacement product, aiming at the common technical bottlenecks in the existing nutritional meal replacement products, such as the loss of activity of functional active ingredients (such as water-soluble EGCG and fat-soluble nutrients) during processing and storage, low bioavailability, poor physical stability of products, single form, and difficulty in achieving precise personalized adaptation of nutritional components.

[0009] The core innovation of the present application lies in the proposed "imitation building block" layer-by-layer construction strategy. This strategy first constructs precise water-phase functional core (for encapsulating and protecting functional factors such as EGCG) and oil-phase domain (for loading fat-soluble active ingredients) as independent basic functional units. Then, according to the preset spatial assembly logic and optimized ratio, these units are driven to perform ordered and controllable hierarchical compounding and interface fusion at the mesoscale, thereby assembling and constructing a structured core matrix with clear topological hierarchy, self-stable three-dimensional colloid network, and component spatiotemporal synergistic release characteristics, like building a precise structure.

[0010] The matrix not only provides multiple protection for the sensitive active ingredients, significantly improves the processing stability and bioavailability, but also serves as a flexible customizable and programmable "nutrient delivery base platform", laying the foundation for building a comprehensive and stable nutrient system. Based on this platform, through systematic strengthening and structural processing of nutrient components, two terminal product forms can be flexibly derived: one is a stable full-nutrition liquid beverage that can be directly consumed; the other is a solid instant powder with rapid rehydration and high dispersibility, which is transformed by integrating functional excipients and spray drying technology.

[0011] The method realizes efficient and controllable transformation from the same precise matrix to multi-form products. The types, compounding and dosage of each component in the system can be independently designed and replaced as "functional units" for flexible adjustment and combination, showing high design freedom and personalized customization potential, so as to accurately adapt to different nutritional and health needs in diversified scenarios such as special medical foods, sports nutrition and daily health management.

[0012] To achieve the above purpose, the preparation process and principle of the present application are as follows: (1) Precise construction of water phase functional core: using structure-controllable molecular assembly or nanometer precipitation process, functional nanoparticles with high loading of epigallocatechin gallate are prepared. Through carrier material selection and surface property regulation, the nanoparticles, as the core functional unit of the system, have uniform nanoscale, excellent colloidal dispersion stability and interface activity potential, laying a foundation for subsequent hierarchical assembly; (2) Construction of oil phase domain: at least one fat-soluble active ingredient is efficiently loaded in the oil phase by high-energy emulsification techniques such as high-pressure microjet or high-speed shear, forming a nanoemulsion with narrow particle size distribution, clear interface composition and thermodynamic / kinetic stability. This module, as a structural unit and fat-soluble carrier of the system, not only provides physical support, but also regulates the stability of the overall system through its interface membrane characteristics; (3) Hierarchical assembly of core matrix: the water phase functional core prepared in step (1) and the oil phase domain prepared in step (2) are placed in a mild laminar shear field according to the optimized volume ratio of 0.5:1-2:1 for controllable mixing. This process aims to promote interface contact, molecular rearrangement and interaction between the two phases, realize the structural transition from "particle / drop" discrete units to "core-shell" or "interpenetrating network" composite matrix, and assemble a composite matrix with ordered micro-topology, excellent physical stability and active ingredient delivery synergy; (4) Construction, reinforcement and structuring of the complete nutrition network: In the assembled hierarchical composite matrix, maltodextrin as a continuous phase regulator and stabilizer in the aqueous phase, compound salts providing essential minerals (such as calcium carbonate, zinc sulfate, and sodium chloride), and various vitamins including vitamin C are systematically introduced. Through high-speed shearing or high-pressure homogenization, these added components are made to physically entangle, electrostatically combine or hydrogen bond with the original matrix at the colloidal and molecular levels, so as to achieve uniform dispersion and deep structural interweaving, and finally construct a composite nutrition delivery system with a stable three-dimensional gel network structure, a complete nutritional spectrum and good taste; (5) Targeted regulation and transformation of end product form: Inulin is added to the nutrient delivery system obtained in step (4) as dietary fiber and molding aid. After homogenization, spray drying technology is used for dehydration, solidification and microencapsulation to obtain solid meal replacement powder with excellent flowability, solubility and dispersibility.

[0013] Preferably, in step (2), the fat-soluble active ingredient is selected from one or more of vitamin A, vitamin E, lycopene, and β-carotene, and its type, combination and concentration can be modularly adjusted and personalized according to product requirements.

[0014] Preferably, in step (4), the amount of maltodextrin added accounts for 15–25% of the total mass of the system; the concentration of vitamin C is 0.1–2 mg / mL, calcium carbonate is 0.1–2 mg / mL, zinc sulfate is 0.01–0.5 mg / mL, and sodium chloride is 3–5 mg / mL. This concentration range ensures a balance between nutritional effectiveness, system stability, and sensory acceptability.

[0015] Preferably, in step (4), the homogenization process is performed using high-pressure homogenization, with a pressure range of 30–80 MPa, and the process is repeated 1–3 times.

[0016] Preferably, in step (5), the amount of inulin added accounts for 0–5% of the total mass of the nutrient delivery system to be dried. This range of addition is optimized to promote powder formation and improve reconstitution while avoiding negative impacts on the system viscosity and spray drying efficiency.

[0017] Preferably, in step (5), the spray drying process parameters are: inlet air temperature 140–170 ℃, fan frequency 25–40 Hz, feed pump speed 7–10 rpm, and atomization pressure 0.1–0.5 MPa. This combination of parameters aims to achieve a balance between efficient moisture removal, good particle formation, and minimizing the degradation of heat-sensitive components.

[0018] Compared with existing nutritional meal replacement products, the beneficial effects and advantages of this invention are as follows: (1) Raw material compliance and functional enhancement: The functional factors (such as EGCG, lycopene, and beta-carotene) used in the present application all meet the GB 2760-2024 "National Food Safety Standard Food Additive Use Standard", and the addition amount is strictly controlled within the safety limit range. Through the efficient encapsulation and stabilization of the nano delivery system, not only the processing tolerance and storage stability of each factor are significantly improved, but also the overall nutritional value of the composite nutritional delivery system is enhanced through the improvement of nutritional synergy and bioavailability, providing a reliable technical path for the large-scale and high-value application of these active ingredients in functional foods.

[0019] (2) System super-stability and process adaptability: The composite nutritional delivery system based on the double nano co-delivery system exhibits excellent long-term physical stability, effectively resisting phenomena such as phase separation, coalescence, and precipitation during storage, and maintaining a uniform dispersed state. The system has good mechanical and processing tolerance, and can adapt to the mixing, homogenization, transportation, and filling process links in industrial production, ensuring the high uniformity and stability of product quality under large-scale production conditions.

[0020] (3) Functional design and performance optimization of powder: By introducing inulin into the composite nutritional delivery system and using spray drying technology, a composite nutritional meal replacement powder is successfully prepared. Inulin, as a high-quality dietary fiber, not only imparts prebiotic function to the product and promotes intestinal health, but also plays a key role in the spray drying process. It forms a rigid and flexible microcapsule wall material with malt dextrin, effectively inhibiting oil migration and surface oil formation during drying; its hydrophilic properties help to reduce the water activity of the powder and improve the storage stability; at the same time, inulin can increase the glass transition temperature of the powder and improve the particle surface morphology, thereby significantly optimizing the product's flowability, dispersibility, and reconstitution, making it have excellent commercial applicability in storage, transportation, and consumption.

[0021] (4) Microstructure regulation and macro-property improvement: In the spray-dried powder, inulin and malt dextrin form a unique microstructure through intermolecular interactions. This structure not only provides a good mechanical barrier to reduce the loss of active ingredients, but also reduces the free water content of the system by binding water molecules, fundamentally improving the physicochemical stability of the product. In addition, this structure design effectively regulates the adhesion and cohesion of the powder, giving it ideal flow and filling properties, meeting the strict requirements of industrial packaging, storage, and circulation.

[0022] (5) Whole-chain safety and industrialization advantage: The raw materials selected by the application are food grade, safe and harmless, and the system does not rely on synthetic emulsifiers. The whole preparation process uses water as the medium, without the use of organic solvents, with simple process, mild conditions, low energy consumption, in line with the concept of green production. From raw materials to process, the whole-chain safety and economy of the technology make it have significant cost advantage and large-scale production potential, easy to realize the rapid transformation from laboratory to factory and commercial application. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 Average particle size and PDI of Example 1 after storage at different temperatures for 100 days 90 Particle size.

[0024] Figure 2 Zeta potential of Example 1 after storage at different temperatures for 100 days.

[0025] Figure 3 Centrifugal sedimentation rate of Example 1 after storage at different temperatures for 100 days.

[0026] Figure 4 pH change of Example 1 after storage at different temperatures for 100 days.

[0027] Figure 5 Fat oxidation of Example 1 after storage at different temperatures for 100 days.

[0028] Figure 6 Vitamin content of Example 1 after storage at different temperatures for 100 days.

[0029] Figure 7 TGA analysis of Examples 2-5.

[0030] Figure 8 Thermal stability analysis of Examples 2-5.

[0031] Figure 9 Scanning electron microscope of Examples 2-5.

[0032] Figure 10 Wetting time of Examples 2-5 at different water temperatures.

[0033] Figure 11 Average particle size and PDI of rehydrated emulsion of Examples 2-5 at different water temperatures.

[0034] Figure 12 Appearance chart of Examples 1-5. DETAILED DESCRIPTION

[0035] The following examples further illustrate the specific implementation of the present application, and the scope of the present application is not limited thereto.

[0036] Wherein, the test method used in the present embodiment is a routine method unless otherwise specified; the materials and reagents (whey protein isolate, chicken egg white albumin, malt dextrin, EGCG, lycopene, β-carotene, etc.) used are commercially available unless otherwise specified.

[0037] EGCG: epigallocatechin gallate; WPI: whey protein isolate; OVA: chicken egg white albumin; PC: citrus pectin; MG: mogroside.

[0038] Example 1: Preparation of a composite nutrient delivery system WPI (1500 mg) was added to ultrapure water (50 mL), and after complete dissolution, the pH was adjusted to neutral and hydrated overnight. Then, EGCG (50 mg) was added to the WPI aqueous solution, and the mixture was homogenized 3 times at 400 Bar to obtain a WPI-EGCG mixed solution. PC (750 mg) was added to ultrapure water (50 mL), and after complete dissolution, the pH was adjusted to neutral. The WPI-EGCG mixed solution and the PC solution were mixed in a volume ratio of 1:1, and the pH was adjusted to 4.0 to obtain an EGCG-loaded nanoparticle.

[0039] OVA (3000 mg) was added to ultrapure water (100 mL), and after complete dissolution, the pH was adjusted to 4.0. After hydration overnight, the supernatant was obtained by centrifugation at 10000 rpm for 25 min. Then, MG (800 mg) was added to the OVA supernatant, and the mixture was stirred and dissolved to obtain an OVA-MG mixed solution. Vitamin A (0.675 mg), vitamin E (2.5 mg), lycopene (5 mg), and β-carotene (5 mg) were added to flaxseed oil (10 mL) and dissolved thoroughly. The OVA-MG mixed solution and the flaxseed oil were mixed in a volume ratio of 9:1, sheared at 11000 rpm for 5 min, and then homogenized 3 times at 1000 Bar to obtain a primary nano delivery system. Then, PC (2000 mg) was added to ultrapure water (50 mL), and after complete dissolution, the pH was adjusted to 4.0. The primary nano delivery system and the PC solution were mixed in a volume ratio of 2:1, and after thorough stirring, a double-layered nano delivery system loaded with vitamin A, vitamin E, lycopene, and β-carotene was obtained.

[0040] The EGCG-loaded nanoparticles (100 mL) were mixed with the double-layer nanoemulsion loaded with vitamin A, vitamin E, lycopene and beta-carotene (150 mL), vitamin C (25 mg), calcium carbonate (42.5 mg), zinc sulfate (15.75 mg), sodium chloride (1105 mg) and maltodextrin (50 g) were added, stirred at 800 rpm for 1.5 h, and after complete dissolution, the composite nutritional delivery system was obtained.

[0041] Example 2: Preparation of a composite nutritional delivery system meal replacement powder According to the process scheme in Example 1, a composite nutritional delivery system was prepared, and a composite nutritional meal replacement powder was prepared by spray drying. The preparation process was as follows: the composite nutritional delivery system was spray dried, the inlet air temperature of spray drying was 150 °C, the peristaltic pump parameters were 7 rpm, the fan frequency was 38 Hz, and the atomization pressure was 0.1 Mpa, and the composite nutritional meal replacement powder was obtained.

[0042] Example 3: Preparation of a composite nutritional delivery system meal replacement powder containing inulin (3 g) According to the process scheme in Example 1, a composite nutritional delivery system was prepared, and a composite nutritional meal replacement powder was prepared by spray drying after adding inulin. The preparation process was as follows: Inulin (3 g) was added to the composite nutritional delivery system (250 mL), and after complete dissolution, spray drying was carried out, the inlet air temperature of spray drying was 150 °C, the peristaltic pump parameters were 7 rpm, the fan frequency was 38 Hz, and the atomization pressure was 0.1 Mpa, and the composite nutritional meal replacement powder containing inulin was obtained.

[0043] Example 4: Preparation of a composite nutritional delivery system meal replacement powder containing inulin (7 g) According to the process scheme in Example 1, a composite nutritional delivery system was prepared, and a composite nutritional meal replacement powder was prepared by spray drying after adding inulin. The preparation process was as follows: Inulin (7 g) was added to the composite nutritional delivery system (250 mL), and after complete dissolution, spray drying was carried out, the inlet air temperature of spray drying was 150 °C, the peristaltic pump parameters were 7 rpm, the fan frequency was 38 Hz, and the atomization pressure was 0.1 Mpa, and the composite nutritional meal replacement powder containing inulin was obtained.

[0044] Example 5: Preparation of a composite nutritional delivery system meal replacement powder containing inulin (12 g) According to the process scheme in Example 1, a composite nutritional delivery system was prepared, and a composite nutritional meal replacement powder was prepared by spray drying after adding inulin. The preparation process was as follows: The inulin (12 g) was added into the composite nutrition delivery system (250 mL), and after being dissolved thoroughly, spray drying was carried out, the inlet temperature of the spray drying was 150 ℃, the peristaltic pump parameters were 7 rpm, the fan frequency was 38 Hz, and the atomization pressure was 0.1 Mpa, to obtain the composite nutrition meal replacement powder containing inulin.

[0045] Experimental example 1: average particle size and D 90 Particle size The composite nutrition delivery system prepared in example 1 was taken as the experimental sample, and the average particle size and D 90 Particle size, before testing, the composite nutrition delivery system was diluted 100 times with ultrapure water with pH 4.0.

[0046] By Figure 1 The average particle size and D 90 The results of the average particle size and D 90 Particle size were 628.23 ± 20.40 nm and 1179.33 ± 143.11 nm respectively, which indicated that the composite nutrition delivery system had not only small particle size value, but also better particle size distribution. After being placed at 4 ℃ and 25 ℃ for 100 d, the average particle sizes of the composite nutrition delivery system were 680.03 ± 16.82 nm and 705.83 ± 20.54 nm respectively, and the D 90 Particle sizes were 1510 ± 85.44 nm and 1676.67 ± 200.33 nm respectively. That is, after being placed at 4 ℃ and 25 ℃ for 100 d, the average particle size and D 90 Particle size of the composite nutrition delivery system still changed in a small range, which indicated that the composite nutrition delivery system prepared in the manner of the application had good storage stability, and this stability was significantly better than that of the conventional emulsion system.

[0047] Experimental example 2: determination of zeta potential The composite nutrition delivery system prepared in example 1 was taken as the experimental sample, and the zeta potential after being placed at 4 ℃ and 25 ℃ for 100 d was determined by Zetasizer Nano ZS90, and before testing, the composite nutrition delivery system was diluted 100 times with ultrapure water with pH 4.0. Figure 2 The zeta potential of example 1, from the figure, it can be seen that no matter how the storage temperature changes, the zeta potential of the composite nutrition delivery system after being stored for 100 d is still lower than -20 mV, which indicates that there is strong electrostatic repulsion between the droplets, so that the system always presents a stable and uniform state.

[0048] Experimental example 3: centrifugal precipitation rate Using the composite nutrient delivery system prepared in Example 1 as the experimental sample, the weight of the empty centrifuge tube was... m 0. Take 2 mL of the combined nutrient delivery system into a centrifuge tube and record the weight at this point. m 1. Centrifuge the emulsion at 4000 rpm for 20 min, retain the precipitate and weigh it. m 2. The centrifugal sedimentation rate of the compound nutrient delivery system was determined using the following formula ( CPR ,%):

[0049] from Figure 3 As can be seen, after storage at 4 ℃ and 25 ℃ for 100 days, the centrifugal sedimentation rate of the combined nutrient delivery system increased from the initial 0.92 ± 0.19% to 4.13 ± 0.66% and 7.43 ± 0.67%, respectively. This indicates that a small amount of milk fat floated to the surface during storage, leading to the increase in the centrifugal sedimentation rate. However, the combined nutrient delivery system still exhibits good overall stability.

[0050] Experiment Example 4: pH Change Using the composite nutrient delivery system prepared in Example 1 as the test sample, the pH change was measured using a pH meter as follows: Figure 4 As shown in the figure, the pH of the samples stored at different temperatures all showed a decreasing trend. After 100 days of storage at 4 ℃ and 25 ℃, the pH decreased from 4.37 ± 0.02 to 4.30 ± 0.02 and 4.26 ± 0.01, respectively. This trend is attributed to the oxidation or non-enzymatic degradation of proteins, fats, vitamins, and other components in the emulsion, the Maillard reaction between carbohydrates and proteins to generate acidic substances, and the release of H+ from emulsifiers or polysaccharides. + The combined effect is the result. In summary, pH changes in the complex nutrient delivery system at different temperatures are not significant.

[0051] Experimental Example 5: Fat Oxidation Using the composite nutrient delivery system prepared in Example 1 as the test sample, lipid oxidation was measured using peroxide value (ADS-F-YH016, Jiangsu Aidisheng Biotechnology Co., Ltd.) and malondialdehyde (A003-2-2, Nanjing Jiancheng Bioengineering Institute) detection kits, respectively. The results are as follows: Figure 5The initial peroxide value and malondialdehyde were 12.36 ± 1.16 μg / mL and 0.38 ± 0.13 nmol / mL, respectively. After 100 days of storage at 4 ℃ and 25 ℃, the peroxide value increased to 49.30 ± 1.08 μg / mL and 126.40 ± 9.38 μg / mL, and the malondialdehyde content increased to 4.97 ± 0.31 nmol / mL and 6.48 ± 0.26 nmol / mL. Since the peroxide value is an early product of fat oxidation, it can reflect the degree of fat oxidation. The peroxide value of the composite nutrient delivery system stored for 100 days was still much smaller than the peroxide value limit specified in GB 2716-2018 National Food Safety Standard Vegetable Oil, indicating that the fat oxidation of the composite nutrient delivery system was weak.

[0052] Experimental Example 6: Vitamin Content The composite nutrient delivery system prepared in Example 1 was used as the test sample, and the residual amounts of vitamin C, vitamin A, and vitamin E therein were determined. The content of vitamin C was determined by reference to the third method 2,6-dichloroindophenol titration method in GB 5009.86-2026, and the contents of vitamin A and vitamin E were determined by reference to the first method reverse phase high performance liquid chromatography method in GB 5009.82-2016. The results are shown in Table 2. Figure 6 The residual amounts of vitamin C after 100 days of storage at 4 ℃ and 25 ℃ were 41.32 ± 2.79% and 33.81 ± 3.97%, respectively; the residual amounts of vitamin A were 70.14 ± 2.10% and 60.36 ± 2.70%, respectively; and the residual amounts of vitamin E were 70.09 ± 4.57% and 55.55 ± 13.10%, respectively. The degradation of vitamin C was higher than that of vitamin A and vitamin E. This was mainly due to the fact that vitamin C was dissolved in the aqueous phase and mainly played an antioxidant role to inhibit fat oxidation, while vitamin A and vitamin E were encapsulated in the nanoemulsion and had enhanced resistance to environmental stress.

[0053] Experimental Example 7: Surface Oil and Oil Encapsulation Rate The composite nutrient meal powders prepared in Examples 2-5 were used as the experimental samples. A portion of the powder was placed in a 110 ℃ oven, and the weight at this time was recorded as m 1. Then 20 mL of n-hexane was added, vortexed and centrifuged at 10000 rpm for 15 min, the supernatant was removed, and the above steps were repeated twice. The obtained precipitate was placed in a 110 ℃ oven until the weight was constant, and the weight at this time was recorded as m 2. The surface oil content (g / 100g) and oil encapsulation rate (%) can be calculated by the following formula, and the results are shown in Table 1. SOC EE , %.​

[0054]

[0055]

[0056] Table 1 Surface oil and oil encapsulation rate of Example 2-5

[0057] The results of Table 1 show that the addition of inulin can reduce the content of surface oil and increase the oil encapsulation rate compared with Example 2. This phenomenon is mainly related to the structure of inulin itself. The large amount of -OH in the inulin molecule can form hydrogen bonds with proteins and polysaccharides, increasing the thickness of the interfacial film, and thus improving the blocking effect of the emulsion on oil droplets during the atomization stage. In addition, inulin itself has strong water absorption, which can reduce the evaporation rate of water during the spray drying process, preventing the migration of oil droplets to the surface due to rapid water loss. In summary, the addition of inulin can effectively prevent the leakage of oil droplets and improve the quality of microcapsule powder.

[0058] Experimental Example 8: Measurement of water activity The composite nutritional meal replacement powder prepared in Examples 2-5 was used as the experimental sample. About 1 g of the composite nutritional meal replacement powder was weighed and placed in a 60 mm diameter flat dish, and the water activity was measured using the automatic mode of the crown alpha water activity meter.

[0059] Table 2 Water activity of Example 2-5

[0060] From Table 2, it can be seen that the water activity of Example 2 is higher than that of Examples 3-5. This may be because the large amount of -OH in the molecular structure of inulin can form hydrogen bonds with free water molecules, converting free water in the composite nutritional meal replacement powder into bound water, and the decrease in free water content causes the water activity to decrease. When the water activity is less than 0.60, microorganisms cannot carry out normal physiological metabolic activities. Therefore, the water activity of Examples 2-5 is within the range where microorganisms cannot grow and reproduce.

[0061] Experimental Example 9: Thermogravimetric analysis A thermal analyzer was used to determine the effect of inulin on the thermal decomposition temperature of the microcapsule powder. The initial temperature was set to 40 °C, and the temperature was increased to 550 °C at a rate of 10 °C / min, with an emergency reset temperature of 570 °C. The sweep gas and protective gas flow rate was 20 ml / min.

[0062] Thermogravimetric analysis is a thermal analysis technique that measures the mass change of a sample under programmed temperature control to infer its stability, component content, and decomposition process. Figure 7are the TG and the first derivative dTG of the microcapsule powder of the composite nutritional meal replacement powder prepared in Examples 2-5. According to the thermogravimetric analysis, the weight loss process of all samples can be divided into three stages: the low-temperature stage (0-150 ℃) is mainly caused by water evaporation, and the addition of inulin increases the water evaporation temperature due to hydrogen bonding; the weight loss in the medium-temperature stage (150-300 ℃) is mainly due to protein denaturation and degradation, maltodextrin / inulin polysaccharide chain breakage, and flaxseed oil decomposition. Two degradation peaks appear in this stage, and the sample with inulin shows better thermal stability in the second stage; the weight loss in the high-temperature stage (>300 ℃) corresponds to the further slow degradation of protein / polysaccharide residual components (such as carbonized structures).

[0063] Experimental Example 10: Measurement of thermal stability The composite nutritional meal replacement powder prepared in Examples 2-5 was used as the experimental sample. An appropriate amount of the composite nutritional meal replacement powder was weighed, and the differential scanning calorimeter was used to analyze the thermal properties of the powder. The initial temperature was 20 ℃, and the temperature was increased to 250 ℃ at a rate of 10 ℃ / min. The total test time was 26 min, and the gas flow and protective gas flow rate was 20 ml / min. The obtained relationship between the heat flow rate and the temperature change is shown in Figure 8 , and the data was analyzed using the NETZSCH Assistant 9 software provided with the instrument. The glass transition temperature T g and the specific heat change C p* of Examples 2-5 were calculated using the automatic mode. The results are shown in Table 3.

[0064] Table 3 Thermal properties of Examples 2-5

[0065] As can be seen from Figure 7 , the samples of Examples 2-5 have two endothermic valleys near 80 ℃ and 230 ℃, respectively. They can correspond to different thermal behaviors of the powder sample at low and high temperatures, respectively. As can be seen from Table 3, the glass transition temperature of Examples 2-5 gradually increases, which is related to the hydrogen bond network formed by the -OH in inulin and the -NH2 and -COOH in the protein and the -OH in maltodextrin in the composite nutritional delivery system. Moreover, compared with Example 2, inulin also causes a change in the specific heat change of Examples 3-5, which is also related to the interaction between inulin and maltodextrin and other substances. In summary, the addition of inulin improves the thermal stability of Examples 3-5.

[0066] Experimental Example 11: Observation of micro-morphology The composite nutritional meal replacement powders prepared in Examples 2-5 were used as experimental samples. The micro-morphology of the composite nutritional meal replacement powders was observed using a scanning electron microscope. The samples were treated with gold spraying to enhance conductivity before measurement, and the acceleration voltage was set to 3 kV during measurement. Figure 9 The results of the scanning electron microscope measurement showed that Examples 2-5 all presented roughly spherical particles, but the particles of Example 2 had obvious collapse and shrinkage, while the particles of Examples 3-5 had smoother surfaces. This phenomenon can be related to the rigid structure of inulin itself, which can coordinate with the elastic interfacial film formed by proteins and the like, and can reduce the shrinkage of droplets during spray drying. In addition, due to the long molecular chain and the presence of many -OH groups in inulin, more water molecules can be combined, slowing down the evaporation rate of water during spray drying. This can maximize the formation of a rigid framework of the particles during spray drying earlier than the shrinkage caused by internal water vaporization, thereby forming particles with smoother surfaces. In summary, inulin can improve the surface morphology of Example 2.

[0067] Experimental Example 12: Powder wettability The composite nutritional meal replacement powders prepared in Examples 2-5 were used as experimental samples, and the wettability was tested. The water temperature was set to 20 °C, 55 °C and 80 °C, and 20 mL of ultrapure water was placed in a water bath for heating. About 100 mg of microcapsule powder was weighed and dropped from a fixed height into preheated ultrapure water with a fixed surface area to determine the wettability of the composite nutritional meal replacement powder.

[0068] Figure 10 The wettability times of Examples 2-5 at different water temperatures are shown in the table. As can be seen from the table, compared with Example 2, the wettability times of Examples 3-5 were significantly reduced. This can be attributed to the reduction of inulin in the surface oil of the microcapsule powder, which is more conducive to the contact between water molecules and the powder. In addition, the structure of inulin itself also provides the powder with more water-soluble groups (such as -OH, etc.), and the increase of these groups can increase the adhesion of water molecules on the surface of the microcapsule powder, thereby significantly shortening the wettability time. In addition, when the water temperature increased from 20 °C to 80 °C, the wettability time was shortened from 472.33 ± 19.01 s to 79.67 ± 5.04 s, which is closely related to the decrease of the cohesive force of water molecules at high temperature to accelerate wetting. In summary, regardless of the water temperature, inulin can shorten the wettability time of Examples 3-5 and improve the wettability of the powder.

[0069] Experimental Example 13: Powder reconstitution The composite nutritional meal replacement powder prepared in Examples 2-5 was used as the experimental sample, and powder rehydration test was performed. The water temperature of 20°C, 55°C, and 80°C was set, and 8 mL of ultrapure water was placed in a water bath for heating. Then, about 20 mg of microcapsule powder was weighed and dissolved in the preheated ultrapure water. After waiting for the microcapsule powder to completely dissolve, it was cooled to room temperature, and the re-dissolution characteristics of the composite nutritional meal replacement powder were determined using a Zetasizer Nano ZS90.

[0070] Figure 11 The rehydration emulsion particle size and PDI of Examples 2-5 are shown in the figure. As can be seen from the figure, when the water temperature is low, the particle size and PDI of Example 2-5 dissolved in 20°C water are smaller than those at other temperatures. This may be due to the fact that at low temperature, water slowly penetrates from the surface layer to the interior of the particle under the action of “capillary action”, and the emulsifiers such as proteins re-exert their emulsification performance after rehydration, so that the whole system is relatively uniform and stable, and thus the particle size and PDI are relatively small. When the water temperature is increased to 55°C and 80°C, the particle size of all samples after re-dissolution is larger than that at 20°C water temperature, and the PDI is also increased. This may be due to the fact that when the water temperature is high, the surface of the powder particle is quickly dissolved in water and reaches the glass transition temperature, the surface viscosity increases and the particles are agglomerated, preventing the diffusion of water molecules into the interior of the agglomerate, resulting in poor uniformity of the re-dissolved emulsion. In summary, inulin can improve the uniformity of the re-dissolved emulsion of Examples 3-5.

[0071] Experimental Example 14: Powder flowability The composite nutritional meal replacement powder prepared in Examples 2-5 was used as the experimental sample, and flowability test was performed. The powder with a mass of m was placed in a measuring cylinder, the measuring cylinder was tapped, the powder adhering to the wall was removed, and the volume at this time was recorded as V P . Then the measuring cylinder was continuously raised or lowered until the volume of the powder V T no longer changed, and the bulk density of the powder (ρb, D P g / mL), tap density (ρt, D T g / mL), Carr index (CI, CI %) and Hausner ratio (HR, HR ) were calculated by the following formula, and the calculation results are shown in Table 4.

[0072]

[0073]

[0074]

[0075]

[0076] Table 4 Flow properties of Examples 2-5

[0077] As can be seen from Table 4, the bulk density, Carr index and Hausner ratio of Examples 3-5 are all lower than that of Example 2. Moreover, the bulk density of the powder of Example 5 is 0.19 ± 0.00 g / mL, the tap density is 0.39 ± 0.01 g / mL, the Carr index is 50.91% ± 1.43%, and the Hausner ratio is 2.04 ± 0.06. This shows that inulin can improve the flow properties of the powder, but due to the presence of surface oil and mechanical interlocking between particles, the powder still exhibits weak flowability. In summary, the presence of inulin still has a significant effect on the improvement of the flowability of the powder, and Example 5 is more advantageous in pipeline transportation.

[0078] Experimental Example 15: Appearance of emulsion and meal replacement powder The composite nutritional delivery system obtained in Example 1 and the composite nutritional meal replacement powder obtained in Examples 2-5 were respectively photographed in a folding photo studio, as shown in Figure 12 As can be seen from the figures, the texture of Example 1 is uniform and mainly yellow. The powders obtained by spray drying in Examples 2-5 are also the same color, and there is obvious clumping in Example 2, which can be caused by mechanical interlocking between particles and high surface oil content, while this undesirable phenomenon is significantly improved in Examples 3-5.

[0079] It should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit it. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the present application, and they should all be covered in the scope of the claims of the present application.

Claims

1. A precision nutrient delivery system based on a modular, building-block-like construction of nanostructure units, characterized in that, The system includes an aqueous functional core and an oil-phase structural domain. The aqueous functional core is used to encapsulate and protect functional factors, while the oil-phase structural domain is used to load lipid-soluble active ingredients.

2. The method for preparing the precision nutrient delivery system based on a modular, building-block-like construction of nanostructure units according to claim 1, characterized in that, The method employs a "building block-like" layer-by-layer construction strategy. First, the functionally defined aqueous phase core and oil phase structural domain are precisely constructed as independent basic functional units. Then, based on the preset spatial assembly logic and optimized proportions, these units are driven to undergo orderly and controllable hierarchical composite and interface fusion at the mesoscale. In this way, like assembling a precision structure, a structured core matrix with clear topological hierarchy, self-stabilizing three-dimensional colloidal network, and spatiotemporal synergistic release characteristics of components is assembled and constructed.

3. The method according to claim 2, characterized in that, Specifically, the following steps are included: (1) Preparation of aqueous functional core: The protein carrier was dissolved in water, the pH was adjusted to neutral and hydrated to obtain a protein solution; Epigallocatechin gallate (EGCG) was added to the protein solution and homogenized under high pressure to obtain an EGCG-protein mixture. The EGCG-protein mixture was then mixed with an aqueous solution containing phospholipids, and the pH of the mixed system was adjusted to 3.0-5.0 to obtain EGCG-loaded nanoparticles. (2) Construction of oil phase structural domain and interface engineering: The protein was dissolved in water, the pH was adjusted to 3.0-5.0 and hydrated, and the supernatant was collected after centrifugation and mixed with carbohydrates to obtain an aqueous phase; at least one fat-soluble active ingredient was dissolved in edible oil to obtain an oil phase; the aqueous phase and the oil phase were mixed and subjected to high-speed shear emulsification and high-pressure homogenization in sequence to obtain a primary nanoemulsion; the primary nanoemulsion was mixed with an aqueous solution containing phospholipids to obtain a nanoemulsion loaded with fat-soluble active ingredients; (3) Hierarchical controllable assembly of core matrix: The aqueous functional core obtained in step (1) and the oil structural domain obtained in step (2) are placed in a mild laminar shear field for controllable mixing according to a volume ratio of 0.5:1–2:

1. (4) Construction, strengthening and structuring of the complete nutrition network: In the assembled hierarchical composite matrix, maltodextrin as a continuous phase regulator and stabilizer in the aqueous phase, composite salts that provide essential minerals, and nutrient components are systematically introduced; and the process is carried out by high-speed shearing or high-pressure homogenization. (5) Targeted regulation and transformation of end product form: The above-mentioned structured nutrition delivery system is directly filled as an ready-to-drink steady-state liquid end product; or by integrating specific solid conversion technology, it is transformed into a solid meal replacement powder with rapid rehydration, high dispersibility and good mixing characteristics while protecting the microstructure and active ingredients.

4. The preparation method according to claim 3, characterized in that, In step (5), inulin is added when preparing the solid meal replacement powder, and the amount of inulin added is 0% to 5% of the total mass of the delivery system.

5. The method according to claim 3, characterized in that, The solid-state conversion technology employs spray drying, with the following core process parameters: inlet air temperature 140–170 ℃, centrifugal fan frequency 25–40 Hz, feed pump speed 7–10 rpm, and atomizer pressure 0.1–0.5 MPa.

6. The method according to claim 3, characterized in that, The fat-soluble active ingredient mentioned in step (2) is selected from one or more combinations of the group consisting of vitamin A, vitamin E, lycopene, and β-carotene.

7. The method according to claim 3, characterized in that, The complex salt of minerals mentioned in step (4) includes at least calcium carbonate as a calcium source, zinc sulfate as a zinc source, and sodium chloride as a sodium source and osmotic pressure / flavor modifier; the added nutritional components include at least vitamin C as a key water-soluble antioxidant.

8. The method according to claim 7, characterized in that, In the nutrient delivery system obtained in step (4), the concentration range of each component is controlled as follows: vitamin C 0.1–2 mg / mL, calcium carbonate 0.1–2 mg / mL, zinc sulfate 0.01–0.5 mg / mL, sodium chloride 3–5 mg / mL, and the amount of maltodextrin added accounts for 15% to 25% of the total mass of the system.

9. A nutritional meal replacement product, characterized in that, The product is prepared by the method described in any one of claims 2 to 8.

Images