Lycopene water dispersible powder and preparation method thereof

Abstract

The invention relates to lycopene water dispersible powder and a preparation method thereof, and belongs to the technical field of food additives. The method comprises the following steps: esterifying octadecyl alcohol and food-grade phosphoric acid, and reacting with edible gelatin to prepare modified edible gelatin; then lycopene dry powder is dispersed in ethyl acetate, a compound emulsifier, modified edible gelatin and 1, 3-propylene glycol are added, and preliminary embedding is achieved through high-speed shearing and ultrasonic nanocrystallization treatment; and step-by-step vacuum drying, secondary embedding with an excipient, freezing, crushing and screening are carried out, such that the water dispersible powder with a particle size of 0.1-0.2 mm is prepared. Through the hydrophobic binding and charge repulsion effects of the modified gelatin and the synergistic process of ultrasonic nanocrystallization and double embedding, the technical problems that traditional lycopene is poor in water dispersibility, prone to layering, high in solvent residue and insufficient in stability are solved. The prepared product is suitable for healthy food systems such as water-based food, beverage and the like, and has the advantages of convenience in storage and transportation and high bioavailability.

Description

A lycopene water-dispersible powder and its preparation method Technical Field

[0001] This invention belongs to the field of food additive technology, specifically relating to a lycopene water-dispersible powder and its preparation method. Background Technology

[0002] Lycopene is a natural fat-soluble red pigment with excellent antioxidant and immune-boosting physiological activities, making it highly valuable in the food, health product, and functional beverage industries. However, lycopene lacks hydrophilic groups in its molecular structure, making it highly hydrophobic and prone to intermolecular aggregation. When directly added to water-based food systems, it can lead to uneven dispersion and rapid stratification, severely affecting the product's appearance and functionality.

[0003] To improve the water dispersibility of lycopene, existing technologies mostly employ single emulsification or simple encapsulation processes, which have the following main drawbacks: First, using a single emulsifier for dispersion makes it difficult to achieve interfacial stability across a wide HLB value range, resulting in uneven particle size and easy agglomeration, with the aqueous dispersion showing stratification after standing for several hours. Second, encapsulation processes are mostly one-step solvent drying methods, where the solvent is easily encapsulated by excipients and difficult to completely remove, leading to excessive solvent residue in the product, which does not meet the safety requirements for food-grade production. Third, existing processes generally use large amounts of sugars as excipients, which contradicts the current trend of "reduced sugar and clean labels" in the development of healthy foods. In addition, traditional processes do not effectively stabilize lycopene particles, making the product susceptible to oxidative degradation under the influence of oxygen and light during storage, resulting in a short shelf life and increased storage and transportation costs.

[0004] Therefore, developing a lycopene water-dispersible powder preparation technology that is simple and controllable, has low solvent residue, good dispersion stability, and is compatible with natural and healthy excipients has become a key issue that urgently needs to be addressed in the field of food additives. Summary of the Invention

[0005] The purpose of this invention is to provide a lycopene water-dispersible powder and its preparation method, in order to solve the problems mentioned in the background art.

[0006] The objective of this invention can be achieved through the following technical solution: A method for preparing lycopene water-dispersible powder, comprising the following steps: Step 1, under a nitrogen atmosphere, octadecyl alcohol and food-grade phosphoric acid are mixed in a reaction vessel, the temperature is raised to 140-150℃ under reduced pressure and kept at the temperature for 3-5 hours. After the reaction is completed, the heating is stopped, and the mixture is stirred under reduced pressure for 30-40 minutes to remove residual water from the system. Then the reduced pressure is released and the reaction solution is cooled to room temperature to obtain alkyl phosphate ester.

[0007] The second step involves mixing edible gelatin, alkyl phosphate, and deionized water in a reaction vessel, then adding sodium hydroxide solution to adjust the pH to 8-9 and reacting at 45-55℃ for 1-1.5 hours. After the reaction is complete, the mixture is cooled to room temperature, and acetic acid solution is added to the reaction solution to adjust the pH to 7-7.5. The mixture is then centrifuged and filtered to obtain the filtrate. Finally, the filtrate is freeze-dried to obtain modified edible gelatin.

[0008] Step 3: Under an argon atmosphere, lycopene powder and ethyl acetate are mixed in a reaction vessel and subjected to high-speed shearing at 40-45℃ to form a homogeneous solution. Then, emulsifier, modified edible gelatin, and 1,3-propanediol are added sequentially and soaked for 10-15 minutes. The mixture is then sheared again to form a homogeneous solution and transferred to an ultrasonic generator for nano-homogenization at 40-45℃ to complete the initial encapsulation. The system is then dried under vacuum to remove some of the solvent. Excipients are then added and stirred for 30-40 minutes to complete the secondary encapsulation. Finally, the system is dried under vacuum again to completely remove the solvent, resulting in a block. The block is then frozen, pulverized, and sieved to obtain lycopene water-dispersible powder.

[0009] Furthermore, the emulsifier is a compound system of Span 40 and Tween 80, with a mass ratio of 5:6.

[0010] Furthermore, the excipient is one of tomato powder, water-soluble starch, soy protein isolate, and grape seed extract.

[0011] Furthermore, in the first step, the mass ratio of octadecyl alcohol to food-grade phosphoric acid is 20-25:7-9.

[0012] Furthermore, in the second step, the mass ratio of alkyl phosphate ester to edible gelatin is 10-15:50-150.

[0013] Furthermore, in the third step, the mass ratio of modified edible gelatin, emulsifier, lycopene powder, and excipient is 50-80:45-65:10-15:150-250.

[0014] Furthermore, in the third step, the drying conditions after the secondary embedding are vacuum drying at 55℃ and -0.08MPa for 24-48 hours.

[0015] Furthermore, in the third step, the particle size of the ultrasonic nanoparticles is 50-400 nm.

[0016] Furthermore, the particle size of the lycopene water-dispersible powder after sieving in the third step is 0.1-0.2 mm.

[0017] A lycopene water-dispersible powder, prepared by any of the above steps.

[0018] The beneficial effects of this invention are as follows: 1) This invention first activates more active sites in gelatin by phosphorylation, and then uniformly grafts octadecyl alcohol hydrophobic chains onto these exposed active sites. The long-chain alkyl hydrophobic side chains form a strong hydrophobic interaction with lycopene, improving the encapsulation rate of lycopene. The hydrophilic backbone "locks" lycopene in the aqueous system, enhancing the wettability of the system. At the same time, gelatin molecules provide steric hindrance, and the phosphate groups introduced on the gelatin molecules by phosphorylation will ionize into negatively charged phosphate anions in the aqueous system. Therefore, each lycopene particle encapsulated by modified gelatin will have a negative charge on its surface. Since like charges repel each other, it further prevents the particles from approaching each other and agglomerating, blocking particle collisions and reducing the loss of lycopene in subsequent encapsulation, drying, and sieving processes. All these factors together ensure the lycopene content in the product.

[0019] 2) The modified edible gelatin of this invention is adsorbed onto the surface of lycopene particles through uniformly grafted hydrophobic side chains. The hydrophilic backbone of the gelatin forms an elastic colloidal network on the surface of the lycopene particles. At the same time, the phosphate anions introduced by phosphorylation interact electrostatically with the amino cations present in the amino acids of gelatin, making the gelatin structure more compact. The two work together to form a "dense protein protective layer" on the surface of lycopene particles, which can not only isolate oxygen to avoid oxidative degradation, but also block light to reduce photosensitive degradation, extend the shelf life of the product, and reduce the risk of spoilage during storage and transportation.

[0020] 3) This invention combines emulsifier Span 40 (HLB value of about 6.7) with Tween 80 (HLB value of about 15.0) to achieve a wide HLB value coverage. This combination can stabilize the initial oil / water interface (the microscopic interface between the lycopene-ethyl acetate solution and the aqueous phase components in subsequent processing) and also meet the dispersion requirements of the final product in water. This combination provides more comprehensive emulsification stability.

[0021] 4) The 1,3-propylene glycol added in this invention is a polyol that is both a mild cosolvent and a moisturizing and low-temperature antifreeze agent. In the "freeze-pulverization" stage of the process, it helps to protect the integrity of the embedded structure and prevent the particles from being damaged by ice crystal formation.

[0022] 5) This invention involves a two-step drying process. After the first drying, the solvent load of the system is significantly reduced. At this point, the excipient is added for the final drying, which greatly improves the specific surface area and mass transfer efficiency of solvent evaporation, ensuring that solvent residue can be almost completely removed. Furthermore, after the first drying removes most of the solvent, the system forms a viscous paste. In this high-viscosity matrix, the excipient powder added later is more easily dispersed and embedded evenly under stirring, achieving physical compact mixing and "secondary embedding" to form a stable solid structure, thus solving the inconvenience of liquid products in storage, transportation, and use. Detailed Implementation

[0023] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0024] It should be understood that the expression “one or more of…” individually includes each of the objects described after the expression, as well as various different combinations of two or more of the described objects, unless otherwise understood from the context and usage. The expression “and / or” combined with three or more described objects should be understood to have the same meaning, unless otherwise understood from the context.

[0025] It should be understood that the use of “including,” “having,” or “containing,” including its grammatical synonyms, should generally be understood as open-ended and non-restrictive, for example, not excluding other unstated elements or steps, unless otherwise specifically stated or understood from the context.

[0026] It should be understood that the order of the steps or the order in which certain actions are performed is not important as long as the invention remains operational. Furthermore, two or more steps or actions can be performed simultaneously.

[0027] Furthermore, the numerical ranges and parameters used to define the present invention are approximate values, and the relevant values ​​in the specific embodiments have been presented as precisely as possible. However, any value inevitably contains standard deviations due to individual test methods. Therefore, unless explicitly stated otherwise, it should be understood that all ranges, quantities, values, and percentages used in this disclosure are modified with the word "approximately." Here, "approximately" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a specific value or range. Example 1

[0028] A method for preparing a lycopene water-dispersible powder includes the following steps: Step 1: By mass fraction, high-purity nitrogen gas (purity ≥99.9%) is introduced, with the flow rate controlled at 0.5 L / min, maintaining a slight positive pressure (0.01 MPa). Under the nitrogen atmosphere, 20 parts of octadecyl alcohol and 7 parts of food-grade phosphoric acid are mixed in a reaction vessel, the temperature is raised to 140°C under reduced pressure and kept at that temperature for 3 hours. After the reaction is completed, the heating is stopped, and the mixture is stirred under reduced pressure for 30 minutes to remove residual water from the system. Then the reduced pressure is released and the reaction solution is cooled to room temperature to obtain alkyl phosphate ester.

[0029] Step 2: Mix 50 parts edible gelatin, 10 parts alkyl phosphate, and 500 parts deionized water in a reaction vessel by mass. Then, add sodium hydroxide solution to adjust the pH to 8 and react at 45°C for 1 hour. After the reaction is completed, cool to room temperature, add acetic acid solution to the reaction solution to adjust the pH to 7, and then centrifuge and filter at 4°C and 8000 r / min for 15 minutes to obtain the filtrate. Finally, freeze-dry the filtrate to obtain modified edible gelatin.

[0030] Step 3: According to the mass fraction, introduce high-purity argon gas (purity ≥99.9%) at a flow rate controlled at 0.5 L / min. Under the argon atmosphere, mix 10 parts of lycopene powder and 1200 parts of ethyl acetate in a reaction vessel. Shear the mixture at 8000 r / min for 5 minutes at 40°C to form a homogeneous solution. Then, add 45 parts of emulsifier, 50 parts of modified edible gelatin, and 5 parts of 1,3-propanediol sequentially and soak for 15 minutes. Continue to shear the mixture at 8000 r / min for 5 minutes at 40°C to form a homogeneous solution. Finally, transfer the mixture to an ultrasonic generator at 45°C for further processing. Nanoparticle homogenization was performed to obtain particles with a diameter of 400 nm, completing the initial encapsulation. The system was then vacuum dried to remove some of the solvent, followed by the addition of 150 parts of tomato powder and stirring for 40 min to complete the secondary encapsulation. Finally, the system was vacuum dried at 55℃ and -0.08 MPa for 48 h to completely remove the solvent, resulting in a block. The block was then frozen at -40℃ for 2 h and then fed into a cryogenic pulverizer, where it was pulverized to a particle size of 0.2 mm under liquid nitrogen to obtain lycopene water-dispersible powder. Pulverization equipment parameters: pulverizing disc speed 3000 r / min, feed particle size 9 mm.

[0031] A lycopene water-dispersible powder, prepared by the above steps. Example 2

[0032] A method for preparing a lycopene water-dispersible powder includes the following steps: Step 1: By mass fraction, high-purity nitrogen gas (purity ≥99.9%) is introduced, with the flow rate controlled at 1 L / min, maintaining a slight positive pressure (0.02 MPa). Under nitrogen atmosphere, 21.25 parts of octadecyl alcohol and 7.5 parts of food-grade phosphoric acid are mixed in a reaction vessel, the temperature is raised to 142.5℃ under reduced pressure and kept at this temperature for 4.5 h. After the reaction is completed, the heating is stopped, and the mixture is stirred under reduced pressure for 37.5 min to remove residual water from the system. Then the reduced pressure is released and the reaction solution is cooled to room temperature to obtain alkyl phosphate ester.

[0033] Step 2: According to the mass fraction, 75 parts of edible gelatin, 11.25 parts of alkyl phosphate, and 500 parts of deionized water are mixed in a reaction vessel. Then, sodium hydroxide solution is added to adjust the pH to 8.25 and the mixture is reacted at 47.5℃ for 1.375 hours. After the reaction is completed, the mixture is cooled to room temperature. Acetic acid solution is added to the reaction solution to adjust the pH to 7. The mixture is then centrifuged and filtered at 4℃ and 8500 r / min for 16 minutes to obtain the filtrate. Finally, the filtrate is freeze-dried to obtain the modified edible gelatin.

[0034] Step 3: According to the mass fraction, high-purity argon gas (purity ≥99.9%) is introduced at a flow rate of 1 L / min. Under the argon atmosphere, 11.25 parts of lycopene powder and 1300 parts of ethyl acetate are mixed in a reaction vessel and sheared at 8500 r / min for 6 min at 41.25℃. Then, 50 parts of emulsifier, 60 parts of modified edible gelatin, and 5 parts of 1,3-propanediol are added sequentially and soaked for 13.75 min. The mixture is then sheared at 8500 r / min for 6 min at 40℃ to form a homogeneous solution, which is then transferred to an ultrasonic generator for nano-processing at 41.25℃. The mixture was homogenized to obtain particles with a diameter of 300 nm, completing the initial encapsulation. The system was then vacuum-dried to remove some of the solvent, followed by the addition of 175 parts of water-soluble starch and stirring for 37.5 min to complete the secondary encapsulation. Finally, the mixture was vacuum-dried at 55℃ and -0.08 MPa for 30 h to completely remove the solvent, resulting in a block. The block was then frozen at -35℃ for 2-4 h and then fed into a cryogenic pulverizer, where it was pulverized to a particle size of 0.175 mm under liquid nitrogen to obtain lycopene water-dispersible powder. Pulverizing equipment parameters: pulverizing disc speed 3500 r / min, feed particle size 8 mm.

[0035] A lycopene water-dispersible powder, prepared by the above steps. Example 3

[0036] A method for preparing a lycopene water-dispersible powder includes the following steps: Step 1: By mass fraction, high-purity nitrogen gas (purity ≥99.9%) is introduced, with the flow rate controlled at 1.3 L / min, maintaining a slight positive pressure (0.03 MPa). Under the nitrogen atmosphere, 22.5 parts of octadecyl alcohol and 8 parts of food-grade phosphoric acid are mixed in a reaction vessel, the temperature is raised to 145℃ under reduced pressure and kept at this temperature for 4 hours. After the reaction is completed, the heating is stopped, and the mixture is stirred under reduced pressure for 35 minutes to remove residual water from the system. Then the reduced pressure is released and the reaction solution is cooled to room temperature to obtain alkyl phosphate ester.

[0037] Step 2: By mass, 100 parts of edible gelatin, 12.5 parts of alkyl phosphate, and 500 parts of deionized water are mixed in a reaction vessel. Then, sodium hydroxide solution is added to adjust the pH to 8.5 and the mixture is reacted at 50°C for 1.25 hours. After the reaction is completed, the mixture is cooled to room temperature. Acetic acid solution is added to the reaction solution to adjust the pH to 7.25. The mixture is then centrifuged and filtered at 4°C and 9000 r / min for 17 minutes to obtain the filtrate. Finally, the filtrate is freeze-dried to obtain the modified edible gelatin.

[0038] Step 3: According to the mass fraction, high-purity argon gas (purity ≥99.9%) is introduced at a flow rate of 1.5 L / min. Under the argon atmosphere, 12.5 parts of lycopene powder and 1400 parts of ethyl acetate are mixed in a reaction vessel and subjected to high-speed shearing at 42.5℃ to form a homogeneous solution. Then, 55 parts of emulsifier, 65 parts of modified edible gelatin, and 10 parts of 1,3-propanediol are added sequentially and soaked for 12.5 min. The mixture is then subjected to high-speed shearing at 9000 r / min at 40℃ for 7 min to form a homogeneous solution. Finally, the solution is transferred to an ultrasonic generator for nano-homogenization at 42.5℃. The process yielded particles with a diameter of 200 nm, completing the initial encapsulation. The system was then vacuum-dried to remove some solvent, followed by the addition of 200 parts of soy protein isolate as an excipient. The mixture was stirred for 35 minutes to complete the secondary encapsulation. Finally, it was vacuum-dried at 55℃ and -0.08 MPa for 36 hours to completely remove the solvent, resulting in a block. This block was then frozen at -30℃ for 3 hours and fed into a cryogenic grinder, where it was pulverized in liquid nitrogen to a particle size of 0.15 mm, yielding lycopene water-dispersible powder. The grinding equipment parameters were: grinding disc speed 4000 r / min, feed particle size 8 mm.

[0039] A lycopene water-dispersible powder, prepared by the above steps. Example 4

[0040] A method for preparing a lycopene water-dispersible powder includes the following steps: Step 1: By mass fraction, high-purity nitrogen gas (purity ≥99.9%) is introduced, with the flow rate controlled at 1.6 L / min, maintaining a slight positive pressure (0.04 MPa). Under nitrogen atmosphere, 23.75 parts of octadecyl alcohol and 8.5 parts of food-grade phosphoric acid are mixed in a reaction vessel, the temperature is raised to 147.5℃ under reduced pressure and kept at that temperature for 3.5 h. After the reaction is completed, the heating is stopped, and the mixture is stirred under reduced pressure for 32.5 min to remove residual water from the system. Then the reduced pressure is released and the reaction solution is cooled to room temperature to obtain alkyl phosphate ester.

[0041] Step 2: By mass, mix 125 parts of edible gelatin, 13.75 parts of alkyl phosphate, and 500 parts of deionized water in a reaction vessel. Then, add sodium hydroxide solution to adjust the pH to 8.75 and react at 52.5℃ for 1.125 h. After the reaction is complete, cool to room temperature, add acetic acid solution to the reaction solution to adjust the pH to 7, and centrifuge and filter at 4℃ and 9500 r / min for 15-20 min to obtain the filtrate. Finally, freeze-dry the filtrate to obtain modified edible gelatin.

[0042] Step 3: According to the mass fraction, introduce high-purity argon gas (purity ≥99.9%) at a flow rate controlled at 1.8 L / min. Under the argon atmosphere, mix 13.75 parts of lycopene powder and 1600 parts of ethyl acetate in a reaction vessel. Shear at high speed at 10000 r / min for 9 min at 43.75℃. Then, add 60 parts of emulsifier, 75 parts of modified edible gelatin, and 15 parts of 1,3-propanediol sequentially and soak for 11.25 min. Continue to shear at high speed at 11000 r / min for 8 min at 40℃ to form a homogeneous solution. Transfer the solution to an ultrasonic generator and continue to process at 43.75℃. Nanoparticle homogenization was performed to obtain particles with a diameter of 100 nm, completing the initial encapsulation. The system was then vacuum dried to remove some of the solvent, followed by the addition of 225 parts of excipient grape seed extract. The mixture was stirred for 32.5 min to complete the secondary encapsulation. Finally, the system was vacuum dried at 55℃ and -0.08 MPa for 42 h to completely remove the solvent, resulting in a block. The block was then frozen at -25℃ for 3 h and then fed into a cryogenic grinder to be pulverized to a particle size of 0.125 mm under liquid nitrogen to obtain lycopene water-dispersible powder. The grinding equipment parameters were: grinding disc speed 5000 r / min, feed particle size 7 mm.

[0043] A lycopene water-dispersible powder, prepared by the above steps. Example 5

[0044] A method for preparing a lycopene water-dispersible powder includes the following steps: Step 1: By mass fraction, high-purity nitrogen gas (purity ≥99.9%) is introduced, with the flow rate controlled at 2L / min, maintaining a slight positive pressure (0.05MPa). Under the nitrogen atmosphere, 25 parts of octadecyl alcohol and 9 parts of food-grade phosphoric acid are mixed in a reaction vessel, the temperature is raised to 140℃ under reduced pressure and kept at that temperature for 5h. After the reaction is completed, the heating is stopped, and the mixture is stirred under reduced pressure for 30min to remove residual water from the system. Then the reduced pressure is released and the reaction solution is cooled to room temperature to obtain alkyl phosphate ester.

[0045] Step 2: Mix 150 parts edible gelatin, 15 parts alkyl phosphate, and 1500 parts deionized water in a reaction vessel according to the mass ratio. Then add sodium hydroxide solution to adjust the pH to 9 and react at 45℃ for 1.5h. After the reaction is completed, cool to room temperature, add acetic acid solution to the reaction solution to adjust the pH to 7, and then centrifuge and filter at 4℃ and 10000r / min for 15-20min to obtain the filtrate. Finally, freeze-dry the filtrate to obtain modified edible gelatin.

[0046] Step 3: According to the mass fraction, introduce high-purity argon gas (purity ≥99.9%) at a flow rate of 2 L / min. Under the argon atmosphere, mix 15 parts of lycopene powder and 1800 parts of ethyl acetate in a reaction vessel. Shear at 12000 r / min at 45°C for 5-10 min. Then, add 65 parts of emulsifier, 80 parts of modified edible gelatin, and 20 parts of 1,3-propanediol sequentially and soak for 10 min. Continue to shear at 12000 r / min at 40°C for 10 min to form a homogeneous solution. Transfer the solution to an ultrasonic generator and continue to process at 40°C. Nanoparticle homogenization was performed to obtain particles with a diameter of 50 nm, completing the initial encapsulation. The system was then vacuum-dried to remove some of the solvent, followed by the addition of 250 parts of soy protein isolate and stirring for 30 min to complete the secondary encapsulation. Finally, the system was vacuum-dried at 55℃ and -0.08 MPa for 48 h to completely remove the solvent, resulting in a block. The block was then frozen at -20℃ for 4 h and fed into a cryogenic grinder, where it was pulverized to a particle size of 0.1 mm under liquid nitrogen to obtain lycopene water-dispersible powder. The grinding equipment parameters were: grinding disc speed 6000 r / min, feed particle size 7 mm.

[0047] A lycopene water-dispersible powder, prepared by the above steps.

[0048] Compared with Example 1, Comparative Example 1 did not modify the edible gelatin, and all other raw materials and steps remained unchanged.

[0049] Compared with Example 1, Comparative Example 2 changed the emulsifier to 45 parts by weight of Tween 80, while the other raw materials and steps remained unchanged.

[0050] Compared with Example 1, in Comparative Example 3, drying was not performed after the initial encapsulation in the third step, while the other raw materials and steps remained unchanged.

[0051] Compared with Example 1, Comparative Example 4 did not perform nano-homogenization treatment in the third step, while the other raw materials and steps remained unchanged.

[0052] Experimental Example 1: Examples 1-5 and Comparative Examples 1-4 were subjected to the following performance tests. The test results are shown in Table 1.

[0053] 1. Lycopene encapsulation rate: High performance liquid chromatography (HPLC) was used. The powder sample was extracted with anhydrous ethanol to break the emulsion, and the free lycopene content and total lycopene content were determined. The encapsulation rate was calculated using the formula: Encapsulation rate (%) = (Total lycopene content - Free lycopene content) / Total lycopene content × 100%. The test results are shown in Table 1.

[0054] 2. Water dispersion stability: The sample was dispersed in room temperature pure water at a mass-to-volume ratio of 1:50 (g:mL), magnetically stirred for 5 min, and then allowed to stand. The separation time was recorded. The test results are shown in Table 1.

[0055] 3. Solvent Residue: Gas chromatography (GC) was used. The residual ethyl acetate in the samples was tested according to GB5009.262 "National Food Safety Standard - Determination of Residual Solvents in Food Additives" (residue <50 mg / kg is considered to meet food-grade requirements). The test results are shown in Table 1.

[0056] 4. Lycopene retention rate: The samples were placed in a constant temperature and humidity chamber at 40℃ and 75% relative humidity for accelerated storage for 14 days. The lycopene content was measured on day 0 and day 14, and the retention rate was calculated using the formula: Retention rate (%) = Lycopene content on day 14 / Lycopene content on day 0 × 100%. The test results are shown in Table 1.

[0057] Table 1. Lycopene Encapsulation Rate (%) Water Dispersion and Layering Time (days) Ethyl Acetate Residue (mg / kg) Lycopene Retention Rate (%) Example 1 92 102 88 5 Example 2 93 112 68 6 Example 3 94 122 58 8 Example 4 95 132 48 9 Example 5 96 152 29 1 Comparative Example 1 65 235 50 Comparative Example 2 70 33 260 Comparative Example 3 88 420 07 5 Comparative Example 4 75 130 65 As shown in Table 1, the introduction of modified gelatin significantly improved the encapsulation rate and antioxidant capacity of lycopene, while the encapsulation rate and retention rate of the unmodified gelatin group decreased significantly, demonstrating the synergistic stabilizing effect of "hydrophobic chain binding + charge repulsion". The emulsification stability of the Span 40 and Tween 80 compound system is better than that of a single emulsifier, directly affecting the water dispersion and stratification time. The stepwise drying process can effectively reduce the solvent residue, and the residue of the one-step drying group far exceeds the food-grade standard. Ultrasonic nano-processing can precisely control the particle size and greatly improve water dispersibility, while the particles in the group without ultrasonic treatment are prone to agglomeration and have extremely poor water dispersibility.

[0058] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention, including the best mode, and also to enable any person skilled in the art to practice the present invention, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a lycopene water-dispersible powder, characterized in that, Includes the following steps: Step 1: Octadecyl alcohol and food-grade phosphoric acid undergo an esterification reaction at a temperature of 140-147.5℃ to obtain alkyl phosphate ester; The second step involves the esterification reaction of alkyl phosphate esters and edible gelatin at pH 8-9 and temperature 45-52.5℃ to obtain modified edible gelatin. The third step involves mixing and shearing lycopene powder and ethyl acetate under an argon atmosphere, then adding emulsifier, modified edible gelatin, and 1,3-propanediol in sequence, continuing shearing, and then performing ultrasonic nano-sizing to complete the initial encapsulation. After partial desolvation through vacuum drying, excipients are added and stirred to complete the secondary encapsulation. After complete desolvation through vacuum drying, the mixture is then frozen, and finally pulverized and sieved to obtain lycopene water-dispersible powder.

2. The method for preparing a lycopene water-dispersible powder according to claim 1, characterized in that, The emulsifier is a compound system of Span 40 and Tween 80 in a mass ratio of 5:

6.

3. The method for preparing a lycopene water-dispersible powder according to claim 1, characterized in that, The excipient is one of tomato powder, water-soluble starch, soy protein isolate, and grape seed extract.

4. The method for preparing a lycopene water-dispersible powder according to claim 1, characterized in that, In the first step, the mass ratio of octadecyl alcohol to food-grade phosphoric acid is 20-25:7-9.

5. The method for preparing a lycopene water-dispersible powder according to claim 1, characterized in that, In the second step, the mass ratio of alkyl phosphate ester to edible gelatin is 10-15:50-150.

6. The method for preparing a lycopene water-dispersible powder according to claim 1, characterized in that, In the third step, the mass ratio of modified edible gelatin, emulsifier, 1,3-propanediol, lycopene powder, and excipient is 50-80:45-65:5-20:10-15:150-250.

7. The method for preparing a lycopene water-dispersible powder according to claim 1, characterized in that, The particle size of ultrasonic nano-sizing in the third step is 50-400 nm.

8. The method for preparing a lycopene water-dispersible powder according to claim 1, characterized in that, The drying conditions after the second embedding in the third step are vacuum drying at 55℃ and -0.08MPa for 24-48 hours.

9. The method for preparing a lycopene water-dispersible powder according to claim 1, characterized in that, The particle size of the lycopene water-dispersible powder after sieving in the third step is 0.1-0.2 mm.

10. The lycopene water-dispersible powder obtained by the preparation method according to claim 1.