High-efficiency preparation method and application of torreya grandis ethyl aureate

Abstract

The invention belongs to the technical field of golden acid preparation, and relates to an efficient preparation method and application of Chinese torreya golden acid ethyl ester, and the method comprises the following steps: firstly, carrying out composite enzymolysis and low-temperature crystallization pretreatment on cold-pressed Chinese torreya oil to remove interfering fatty acids; then preparing high-purity ethyl aureate by using urea inclusion and directional ester exchange technologies; and then the golden acid is mixed with an antioxidant, starch sodium octenylsuccinate and chitosan to prepare lipid nanoparticles, so that the oxidation stability and water dispersibility of the golden acid are remarkably improved. Finally, the nanoparticles are compounded with components such as sorbitol, pectin and citrus fibers, and the functional gel candy rich in the chrysolic acid is prepared through a dual gel network construction technology. According to the method, the problems that in a traditional method, the extraction purity of the chrysolic acid is low, the stability is poor, and the chrysolic acid is difficult to apply to water-based food are effectively solved, the obtained product is stable in component and good in taste, and high-valued application of the Chinese torreya chrysolic acid ethyl ester is achieved.

Description

Technical Field

[0001] This invention belongs to the field of pine acid preparation technology, and relates to an efficient preparation method of ethyl pine acid from Torreya grandis and its application. Background Technology

[0002] Torreya grandis oil is a unique woody plant oil, rich in a distinctive polyunsaturated fatty acid—piperidine. Piperidine has attracted considerable attention due to its various potential biological activities, including anti-inflammatory, lipid-regulating, and neuroprotective effects, and shows broad application prospects in functional foods, health products, and pharmaceuticals. However, the efficient preparation of piperidine from Torreya grandis oil and its application in food systems (especially gel candies and soft capsules) faces a series of technical challenges.

[0003] 1) Low extraction efficiency and insufficient purity: Traditional methods for separating polyunsaturated fatty acids, such as low-temperature crystallization, solvent extraction, and molecular distillation, are difficult to effectively distinguish between pinocembrin and fatty acids with similar physicochemical properties (such as linoleic acid and oleic acid) when applied to Torreya grandis oil. This results in a low extraction rate of pinocembrin, and the purity of the final product often fails to meet the requirements of high-value-added applications. Existing enzymatic hydrolysis or transesterification processes lack pretreatment of complex components (such as phospholipids and saturated fatty acids) in Torreya grandis oil, resulting in poor reaction selectivity and numerous byproducts, further increasing the difficulty and cost of purification.

[0004] 2) Extremely poor oxidative stability: Pine acid molecules contain multiple conjugated double bonds, making them chemically reactive and highly sensitive to light, heat, and oxygen. During traditional extraction and storage, they are highly susceptible to oxidative rancidity, leading not only to the degradation and inactivation of active ingredients but also to the formation of unpleasant flavor compounds. Existing technologies often mitigate spoilage by adding large amounts of synthetic antioxidants or using nitrogen-filled packaging, but these are only temporary solutions and may raise food safety concerns or affect product flavor.

[0005] 3) Low water dispersibility and bioavailability: Piperidine and its derivatives are highly lipid-soluble and almost insoluble in water. This severely limits their uniform addition and effective application in water-based food systems (such as jellies, beverages, and gel candies). Simple mechanical mixing leads to uneven distribution of active ingredients, easy precipitation, and an oily taste. Furthermore, its release and absorption efficiency (bioavailability) in the human gastrointestinal tract is significantly reduced due to oil-water incompatibility.

[0006] 4) Gel candies have a soft texture and relatively high moisture content. Directly adding pine acid oil will cause severe "oil seepage," damaging the gel structure and resulting in a greasy appearance, poor taste, and short shelf life. Furthermore, the heating and cooking steps during candy manufacturing accelerate the oxidative degradation of pine acid. Current technology lacks an effective carrier system to stably "lock" pine acid within the candy's gel network and achieve controlled release.

[0007] 5) Traditional soft capsules have poor compatibility between the contents and the shell, insufficient self-oxidative stability, limited bioavailability, and stringent requirements for the physical state of the contents in the production process, making it difficult to adapt to the development of high-quality dosage forms of functional oils such as pine acid, which are highly active and easily degradable. Summary of the Invention

[0008] To address the above problems, this invention provides a highly efficient method for preparing ethyl torreya syringate and its application, specifically comprising the following preparation method: Step 1: Heat the cold-pressed torreya nut oil to 40-50℃, then add phosphate buffer solution and compound enzyme preparation sequentially. Stir at 40-50℃ and 200-300 rpm for 3.5-4.5 hours for enzymatic hydrolysis. This mild condition ensures enzyme activity while minimizing the oxidation of pinocembryonic acid. After hydrolysis, raise the temperature to 80-90℃ and maintain this temperature for 8-12 minutes to completely inactivate the enzyme. Cool the temperature to 3-5℃ at a rate of 1.8-2.2℃ / min and allow to stand for crystallization for 10-15 hours. Filter at 3-5℃; the filtrate is the pretreated torreya nut oil. During this process, hydrolyzed free saturated fatty acids in the torreya nut oil precipitate as crystals. Subsequently, under low-temperature filtration conditions, a clear torreya nut oil liquid is obtained. This step removes some solid fats, increasing the relative content of pinocembryonic acid glycerides in the torreya nut oil and reducing interference from saturated fatty acids in subsequent extraction processes.

[0009] Preferably, the mass ratio of the torreya oil, phosphate buffer solution and compound enzyme preparation is 100:(10-20):(1-2).

[0010] Preferably, the phosphate buffer solution is composed of disodium hydrogen phosphate, potassium dihydrogen phosphate, and water in a mass ratio of (9-10):(1-2):(900-1000).

[0011] Preferably, the compound enzyme preparation is a lipase and a phospholipase in a mass ratio of (8-9):(1-2). Most preferably, the lipase is Novozymes 435 lipase and the phospholipase is phospholipase A2. The lipase mainly targets the ester bond at the 1,3 position of triglycerides for mild hydrolysis, while phospholipase A2 can hydrolyze any phospholipids that may be present, releasing bound fatty acids and improving overall efficiency.

[0012] Step two: Mix the pretreated torreya oil and the encapsulating agent, stir in a water bath at 70-80℃ and 60-90rpm until dissolved, then cool to 20-25℃ at a rate of 0.4-0.6℃ / min, and let stand at 3-5℃ for 20-25 hours. During this process, urea molecules preferentially form stable hexagonal inclusion crystals with highly linear free saturated fatty acids and some monounsaturated fatty acids in the solution and precipitate out. Meanwhile, glyceryl arbutin, containing multiple cis double bonds and with bent molecular chains, is largely retained in the solution and not encapsulated due to its spatial structure hindering its entry into the urea crystal channels. The residue is filtered, and the filter residue is urea inclusion crystals (which can be recovered as a byproduct of fatty acids). A catalyst is added to the filtrate, and the mixture is stirred at 50-60℃ and 120-150rpm for 2-3 hours under inert gas protection. During this process, glycerol esters of ginsenosides undergo transesterification with ethanol to generate ethyl ginsenosides. By precisely controlling the reaction time and temperature, glycerol esters containing ginsenosides can be preferentially reacted, while the remaining small amount of other polyunsaturated fatty acid glycerol esters react to a relatively low degree.

[0013] Then, add 8-12% (w / w) of citric acid aqueous solution to neutralize the catalyst and terminate the reaction. Let it stand at 50-60℃ for 25-35 min to remove the lower glycerol phase. The upper ester phase is purified by distillation at 75-85℃ feed, 125-135℃ distillation temperature, and 0.1-0.2 Pa. During this process, ethyl pinenate (with a high boiling point) is efficiently separated from most other fatty acid ethyl esters (such as ethyl oleate, ethyl linoleate, etc.). Collect the distilled heavy phase to obtain high-purity (≥95%) ethyl pinenate.

[0014] Preferably, the mass ratio of the torreya oil, encapsulating agent, catalyst and citric acid aqueous solution is 100:(340-350):(0.8-1):(0.8-1.2).

[0015] Preferably, the encapsulating agent is urea and ethanol in a mass ratio of (40-50):300.

[0016] Preferably, the catalyst is sodium acetate.

[0017] Step 3: Ethyl pineate and antioxidants are mixed to obtain an oil phase. Water is heated to 65-75℃, and sodium octenyl succinate starch and chitosan are added to obtain an aqueous phase. The oil phase is heated to 65-75℃ and then injected into the aqueous phase at a rate of 4-6% of total volume / min. The mixture is sheared at 7000-9000 rpm for 4-6 min, homogenized by cycling at 70-90 MPa 3-4 times, and allowed to mature at 3-5℃ for 20-25 h to obtain ethyl pineate nanoparticles. During this process, chitosan further assembles at the oil-water interface through electrostatic interactions, forming a dense composite interfacial film with sodium octenyl succinate starch. Simultaneously, the lipid core within the system crystallizes, ultimately forming a lipid nanoparticle structure. The ethyl pineate nanoparticles obtained through this pretreatment have an average particle size of 120-180 mm and an encapsulation efficiency greater than 90%, significantly improving the oxidative stability and water dispersibility of pineate, and providing a structural basis for its subsequent sustained release in gel candies.

[0018] Preferably, the mass ratio of ethyl pine ester, antioxidant, water, sodium octenyl succinate starch and chitosan is 10:(0.5-1):(20-30):(4-6):(1-2).

[0019] Preferably, the antioxidant is vitamin E and rosemary extract in a mass ratio of (4-6):(1-3).

[0020] This invention also provides the application of ethyl pine resin in gel fructose, specifically including the following steps: Step 1: Mix water, sorbitol, maltitol and pectin, stir at 80-90℃ and 60-90rpm for 10-20 minutes to completely dissolve the pectin and mix it thoroughly with the sorbitol solution. Cool down to 55-65℃, then add citrus fiber and agar, and continue stirring for 20-30 minutes. Next, add ethyl torreya syringate nanoparticles, citrus flavoring, erythritol and potassium citrate, and stir for 25-35 minutes to obtain a gel solution.

[0021] Preferably, the mass ratio of water, sorbitol, maltitol, pectin, citrus fiber, agar, ethyl torreya syringate nanoparticles, citrus flavor, erythritol and potassium citrate is (45-55):(30-40):(15-25):(4-6):(8-12):(2-4):(40-45):(0.8-1.2):(0.2-0.4):(0.4-0.6).

[0022] Step two: After injecting the gel solution into the candy mold, cool at 20-25℃ for 1.5-2.5 hours. The agar first forms a thermally reversible rigid gel network, fixing the system in place. Subsequently, the formed candy is refrigerated at 4-8℃ for 45-50 hours to obtain gel candy. During this low-temperature process, low-ester pectin slowly undergoes ionic cross-linking with calcium ions (from the raw materials and water) under acidic conditions, forming another thermally irreversible gel network. Simultaneously, the water activity inside the candy decreases, allowing the water-holding capacity and three-dimensional network structure of the citrus fiber to be fully utilized. Ultimately, a dual gel system is formed inside the candy, with an agar network as the framework, a pectin-citrus fiber composite network filled with and encapsulating ethyl torreya nutate nanoparticles.

[0023] This invention also provides the application of ethyl pine resin in soft capsules, specifically including the following steps: Step 1: Mix ethyl torreya sylvestris nanoparticles, beeswax, and soybean lecithin in a mass ratio of (90-95):(4-6):(2-4). Stir at 65-75℃ and 250-350 rpm for 30-40 minutes until the beeswax is completely melted and the system is homogeneous and transparent, yielding liquid 1. Maintain this temperature for later use to prevent crystallization.

[0024] Step 2: Mix gelatin, glycerin and water in a mass ratio of (35-45):(15-20):(40-45), and stir at 60-70℃, (-0.05)-(-0.07)MPa and 250-350rpm for 50-70 minutes to obtain gel solution 2.

[0025] Step 3: Mix adhesive solution 1 and adhesive solution 2 at a mass ratio of (1-1.2):1, encapsulate using a pelleting machine, with a shell thickness of 0.7-0.9mm, and cure at 20-30℃ and 25-35%RH for 3-5 hours to obtain ethyl pine nutate soft capsules.

[0026] The present invention has the following advantages: 1) This invention innovatively employs a combined process of "enzymatic pretreatment-low-temperature crystallization for impurity removal" and "urea inclusion-targeted transesterification-molecular distillation purification." First, a specific complex enzyme gently hydrolyzes the oil, releasing fatty acids and altering its composition. Combined with low-temperature crystallization, this removes a large amount of interfering saturated and monounsaturated fatty acid solids, resulting in the initial enrichment of the target compound, glyceryl pineate, in the oil phase. Subsequently, the specific inclusion of urea molecules on straight-chain fatty acids is utilized to efficiently remove residual linear interfering fatty acids. After these two impurity removal steps, the concentration of glyceryl pineate in the remaining oil is significantly increased. Based on this optimized substrate, transesterification and vacuum distillation are then performed to maximize the generation and purification efficiency of ethyl pineate, achieving "targeted" extraction and purification of specific structural fatty acids from complex vegetable oils.

[0027] 2) This invention does not rely solely on exogenous antioxidants, but rather constructs a multi-layered stabilizing system that combines internal and external treatments. Internally, esterification converts pine acid into ethyl ester, which is inherently more stable than the free acid form. Externally, purified pine acid ethyl ester is innovatively prepared into lipid nanoparticles. These nanoparticles form a dense composite interfacial film with sodium octenyl succinate starch and chitosan, physically blocking the contact of pro-oxidative factors such as oxygen and metal ions. Simultaneously, the added vitamin E and rosemary extract work synergistically to further scavenge free radicals within the oil phase. This dual strategy of "structural encapsulation + chemical antioxidation" significantly reduces the oxidation rate of pine acid in the final product during processing and storage, maintaining its bioactivity and the product's fresh flavor, thus ensuring long-term storage and sales.

[0028] 3) This invention prepares ethyl pinacid nanoparticles from Torreya grandis, transforming the hydrophobic ethyl pinacid into a nanoscale dispersion system with an average particle size of 120-180 nm and an encapsulation efficiency exceeding 90%. These nanoparticles have a hydrophilic surface, enabling them to remain stably dispersed in the aqueous phase for extended periods without aggregation or oil droplet formation. This not only solves the "oil-water separation" problem caused by direct addition but also significantly increases the contact area between pinacid and gastrointestinal digestive fluids due to its nanoscale size, potentially leading to a significant improvement in its bioavailability in the human body. Furthermore, this uniform and stable nanodispersion is a prerequisite for its successful and stable introduction into the subsequent aqueous phase system of gel candies.

[0029] 4) This invention designs a candy matrix system that matches the properties of lipid nanoparticles. A unique "dual gel network" is constructed using the thermally reversible gel of agar and the cryogenic gel of pectin-citrus fiber. During processing, the candy is first shaped and fixed by the agar network; in subsequent cold-curing, pectin crosslinks with calcium ions and forms a reinforcing network with citrus fiber. Ethyl torreya nutate nanoparticles are cleverly embedded and fixed within the microregions of this dual-network structure. This design brings multiple superior effects: firstly, it avoids oil seepage, resulting in a dry candy surface and uniform texture; secondly, the nanoparticles are physically isolated by the gel network, further slowing down oxidation; thirdly, the addition of citrus fiber enhances chewiness and water retention, improving mouthfeel; finally, the entire system provides functional components while perfectly maintaining the clear appearance, smooth texture, and good elasticity expected of gel candies.

[0030] 5) This invention constructs a composite content of "lipid nanoparticle core-beeswax phospholipid matrix" and combines it with an optimized gelatin shell process, achieving multiple stabilization protections, good production adaptability and potential improvement in bioavailability of pine acid at the dosage form level, and successfully transforming high-purity pine acid into a stable, reliable and easy-to-take soft capsule product. Detailed Implementation

[0031] The technical solutions in the embodiments of the invention are described clearly and completely below. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Example 1 Raw material preparation: Phosphate buffer: disodium hydrogen phosphate, potassium dihydrogen phosphate, and water in a mass ratio of 8.5:1.5:950.

[0033] Compound enzyme preparation: Novozymes 435 lipase and phospholipase A2, in a mass ratio of 9:1.

[0034] Encapsulating agent: urea and ethanol, in a mass ratio of 45:300.

[0035] Antioxidants: Vitamin E and rosemary extract (purchased from Shaanxi Junhe Biotechnology Co., Ltd.), in a mass ratio of 5:2.

[0036] The preparation method is as follows: Step 1: The mass ratio of Torreya grandis oil, phosphate buffer solution, and compound enzyme preparation is 100:15:1.5.

[0037] The cold-pressed torreya oil was heated to 45°C, and phosphate buffer solution and compound enzyme preparation were added in sequence. The mixture was stirred at 45°C and 250 rpm for 4 hours for enzymatic hydrolysis. The temperature was then raised to 85°C and held for 10 minutes to completely inactivate the enzyme. The temperature was then lowered to 4°C at a rate of 2°C / min, and allowed to stand for crystallization for 12 hours. The mixture was then filtered at 4°C, and the filtrate was the pretreated torreya oil.

[0038] Step 2: The mass ratio of torreya oil, encapsulating agent, sodium acetate, and citric acid aqueous solution is 100:345:0.9:1.

[0039] Pretreated Torreya grandis oil and encapsulating agent were mixed and stirred in a water bath at 75°C and 85 rpm until dissolved. The mixture was then cooled to 23°C at a rate of 0.5°C / min and allowed to stand at 4°C for 22 h. After filtration, the filter residue was removed. Sodium acetate was added to the filtrate and the mixture was stirred at 55°C and 130 rpm for 2.5 h under nitrogen protection. The reaction was then terminated by adding a 10% (w / w) citric acid aqueous solution. The mixture was allowed to stand at 55°C for 30 min to remove the lower glycerol phase. The upper ester phase was purified by distillation at 80°C, 130°C, and 0.15 Pa. The heavy phase was collected to obtain ethyl pine resin.

[0040] Step 3: The mass ratio of ethyl pine ester, antioxidant, water, sodium octenyl succinate starch and chitosan is 10:0.8:25:5:1.5.

[0041] Ethyl pineate and antioxidant were mixed to obtain an oil phase. Water was heated to 70°C and sodium octenyl succinate starch and chitosan were added to obtain an aqueous phase. The oil phase was heated to 70°C and then injected into the aqueous phase at a rate of 5% total volume / min. The mixture was sheared at 8000 rpm for 5 min, homogenized by cycling at 80 MPa 4 times, and allowed to stand at 4°C for 24 h to obtain ethyl pineate nanoparticles of Torreya grandis.

[0042] Step four: The mass ratio of water, sorbitol, maltitol, pectin, citrus fiber, agar, ethyl torreya syringate nanoparticles, citrus flavor, erythritol and potassium citrate is 50:35:20:5:10:3:42:1:0.3:0.5.

[0043] Mix water, sorbitol, maltitol and pectin, stir at 85°C and 70 rpm for 15 min to completely dissolve the pectin and mix it thoroughly with the sorbitol solution. Cool down to 60°C, then add citrus fiber and agar, and continue stirring for 25 min. Then add ethyl torreya syringate nanoparticles, citrus flavoring, erythritol and potassium citrate, and stir for 30 min to obtain a gel solution.

[0044] Step 5: After injecting the gel solution into the candy mold, cool at 24°C for 2 hours and then refrigerate at 5°C for 48 hours to obtain the gel candy.

[0045] Step 6: Mix ethyl torreya sylvestris nanoparticles, beeswax and soybean lecithin in a mass ratio of 92:5:3, and stir at 70℃ and 300rpm for 35 minutes to obtain the first solution.

[0046] Step 7: Mix gelatin, glycerin and water in a mass ratio of 40:18:42, and stir at 65℃, -0.06MPa and 300rpm for 60min to obtain gel solution 2.

[0047] Step 8: Mix adhesive solution 1 and adhesive solution 2 at a mass ratio of 1.08:1, encapsulate using a pelleting machine, with a shell thickness of 0.8±1mm, and cure at 25℃ and 30%RH for 4 hours to obtain ethyl pine nutate soft capsules.

[0048] Experimental Example 1 Experimental steps: Take 3 portions of 100.0g cold-pressed Torreya grandis oil, weigh them accurately, and perform enzymatic hydrolysis-low temperature crystallization pretreatment according to step one of Example 1. Collect and weigh the mass of the solid fat (filter residue) obtained after filtration in step one, calculate the solid fat removal rate, evaluate the effect of pretreatment on impurity removal, combine the 3 portions of pretreated Torreya grandis oil, and record the total mass.

[0049] Urea inclusion and transesterification efficiency determination: Pretreated Torreya grandis oil was processed according to step two of Example 1. After the reaction was completed, the mass of the lower glycerol phase was separated and measured, the upper ester phase was collected, and the mass was recorded as the feed for molecular distillation.

[0050] Molecular distillation purification and final product analysis: The upper ester phase was subjected to vacuum molecular distillation, and the mass of the collected ethyl pine ester (distilled heavy phase) was accurately weighed.

[0051] The purity and fatty acid composition of ethyl pine resin in the final product were analyzed by gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC).

[0052] Calculate the total process yield: Ethyl pine ester mass / Initial torreya oil mass × 100%.

[0053] Table 1. Preparation efficiency analysis

[0054] Experimental Example 2 Basic physicochemical properties were determined: The Z-mean particle size and polydispersity index of the nanoparticle dispersion were measured using a dynamic light scattering instrument, the Zeta potential of the nanoparticle surface was measured, and its electrostatic stability was evaluated.

[0055] Encapsulation performance determination: Free ethyl pine resin was separated by ultrafiltration centrifugation (molecular weight cutoff 10 kDa). The total drug concentration and free drug concentration of the nanoparticle dispersion were determined by HPLC, and the encapsulation efficiency and drug loading were calculated.

[0056] Dispersion stability: The nanoparticle dispersion (the mass ratio of ethyl torreya pineate nanoparticles to water was 1:1.5) was stored at 4°C and 25°C for 30 days, respectively. Samples were taken on days 0, 7, 15 and 30 to observe the appearance (whether there was stratification or precipitation) and to measure the changes in particle size and PDI.

[0057] Table 2 Basic Physicochemical Properties

[0058] Table 3. Particle size and PDI variations

[0059] Experimental Example 3 Experimental Procedure: Pure ethyl pineate (product of step two) and ethyl pineate nanoparticles (product of step three) were prepared separately. Both samples were placed in a 60°C constant temperature drying oven for accelerated oxidation testing. Samples were taken on days 0, 7, 14, 21, and 28 to determine the peroxide value (to assess primary oxidation products) and the conjugated diene value (to assess changes in the initial stage of oxidation).

[0060] Table 4 Oxidation Stability

[0061] Test Example 4 Experimental Procedure: Three batches of gel candies were prepared according to the method in Example 1, and the water activity and pH value of the candies were measured. Using a texture analyzer, the hardness, elasticity, and chewiness of the candies were measured on the day of preparation (day 0). Ten trained sensory evaluators rated the fresh candies (9-point scale for preference).

[0062] Evaluation dimensions: Appearance (uniformity of color, dryness of surface), texture (elasticity, smoothness, oiliness), flavor (harmony of citrus aroma, absence of unpleasant odors).

[0063] Storage stability study: Candies were stored in a constant temperature and humidity chamber at 25°C and 60% relative humidity for 90 days. Appearance changes (oiling, stickiness, mold) were observed and recorded on days 0, 30, 60, and 90. Texture changes were measured using a texture analyzer. Ethyl pineate was extracted from samples and its content was determined by HPLC. The retention rate of active ingredients was calculated.

[0064] Table 5 Basic Indicators and Sensory Scores

[0065] Table 6 Storage Stability

[0066] Experimental Example 5 Experimental Procedure: 30 soft capsules prepared in Example 1 were randomly selected and weighed. The average capsule weight and the weight difference (RSD%) were calculated. 10 capsules were randomly selected to measure the shell thickness. 10 soft capsules were taken, and the content of ethyl arbutin in the contents of each capsule was determined. The average value and RSD% were calculated to assess the content uniformity. 50 soft capsules were randomly selected and placed in a constant temperature and humidity chamber at 40℃ and 75% RH for a one-month accelerated test. At the end of the test, samples were taken to determine the retention rate of ethyl arbutin in the contents and the appearance changes were observed. The results are shown in Table 7.

[0067] Table 7 Physicochemical properties of ethyl pine ester soft capsules

[0068] As shown in Tables 1-7, this invention successfully constructed ethyl torreya sylvestris nanoparticles with high encapsulation efficiency and nanoscale particle size. The average particle size was 152 nm, the distribution was uniform (PDI=0.18), the encapsulation efficiency was as high as 93.5%, and the Zeta potential was -32.5 mV, indicating that it has excellent physical stability and efficient active ingredient loading capacity.

[0069] This lipid nanoparticle system exhibits good physical stability, making it particularly suitable for refrigerated storage. After 30 days of storage at 4°C, the average particle size only slightly increased from 152 nm to 158 nm, and the PDI remained below 0.21, indicating a homogeneous and stable system. At room temperature (25°C), the system remained essentially stable for 15 days and did not exhibit significant aggregation within 30 days, demonstrating its stability meets the requirements for production, distribution, and short-term shelf storage.

[0070] The lipid nanoparticle structure provides excellent antioxidant protection for ethyl arbutin. After accelerated oxidation at 60°C for 28 days, the peroxide value of unencapsulated pure ethyl arbutin increased to 35.6 meq / kg, while that after nanoparticle encapsulation only increased to 8.2 meq / kg, representing a reduction in oxidation rate of approximately 77%. This indicates that the dual strategy of "structural encapsulation + antioxidant" can fundamentally and significantly improve the oxidative stability of arbutin.

[0071] The application of lipid nanoparticles in gel candies successfully solved the challenges of active ingredient distribution, exudation, and stability. The prepared gel candies exhibited a uniform texture (hardness 1250g, elasticity 4.2mm) and good sensory evaluation. After 90 days of storage at 25℃ / 60%RH, the retention rate of psoralen in the candies remained as high as 90.8%, with no oil spots on the surface and good textural retention, demonstrating that this nanoparticle-gel dual system can achieve efficient encapsulation, stable storage, and quality maintenance of functional ingredients.

[0072] The soft capsule preparation process is stable and feasible, and the resulting products are of uniform quality (small differences in capsule weight and content). They also exhibit good physical and chemical stability under accelerated conditions, and can effectively encapsulate and protect the active ingredient of ethyl torreya sylvestris.

[0073] In summary, this invention forms a complete and effective technical solution, from the efficient preparation of high-purity ethyl arbutin to the construction of a stable and high-load nanodelivery system, and finally to its successful and stable application in high-moisture food matrices. This fully verifies its innovation, feasibility and practical value.

[0074] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A highly efficient method for preparing ethyl torreya sylvestris, characterized in that, Includes the following steps: Step 1: Mix cold-pressed torreya oil, phosphate buffer solution and compound enzyme preparation at a mass ratio of 100:(10-20):(1-2) and enzymatically hydrolyze for 3.5-4.5 hours. Heat to 80-90℃ and maintain for 8-12 minutes to inactivate the enzyme. Cool to 3-5℃ and let stand to crystallize for 10-15 hours. Filter at 3-5℃. The filtrate is pretreated torreya oil. Step 2: Mix the pretreated Torreya grandis oil and the encapsulating agent, stir in a water bath at 70-80℃ until dissolved, cool to 20-25℃, let stand at 3-5℃ for 20-25 hours, filter, remove the filter residue, add the catalyst to the filtrate, react at 50-60℃ for 2-3 hours under inert gas protection, then add citric acid aqueous solution to terminate the reaction, let stand, remove the lower glycerol phase, and purify the upper ester phase by vacuum distillation to obtain ethyl pinenate. The mass ratio of the torreya nut oil, encapsulating agent, catalyst, and citric acid aqueous solution is 100:(340-350):(0.8-1):(0.8-1.2). Step 3: Mix ethyl pine ester and antioxidant to obtain an oil phase. Heat water and add sodium octenyl succinate starch and chitosan to obtain an aqueous phase. Heat the oil phase to the same temperature as the aqueous phase and mix them. Shear and homogenize in sequence, and let stand at 3-5℃ for 20-25 hours to obtain ethyl pine ester nanoparticles of Torreya grandis. The mass ratio of ethyl pine ester, antioxidant, water, sodium octenyl succinate starch and chitosan is 10:(0.5-1):(20-30):(4-6):(1-2).

2. The method for efficiently preparing ethyl torreya sylvestris acid according to claim 1, characterized in that, The phosphate buffer solution mentioned in step one is disodium hydrogen phosphate, potassium dihydrogen phosphate and water, with a mass ratio of (9-10):(1-2):(900-1000).

3. The method for efficiently preparing ethyl torreya sylvestris var. chinensis according to claim 1, characterized in that, The compound enzyme preparation mentioned in step one is lipase and phospholipase in a mass ratio of (8-9):(1-2).

4. A method for the efficient preparation of ethyl torreya sylvestris var. chinensis according to claim 1 or 3, characterized in that, The lipase is Novozymes 435 lipase, and the phospholipase is phospholipase A2.

5. The method for efficiently preparing ethyl torreya sylvestris var. chinensis according to claim 1, characterized in that, The embedding agent mentioned in step two is urea and ethanol in a mass ratio of (40-50):

300.

6. The method for efficiently preparing ethyl torreya sylvestris var. chinensis according to claim 1, characterized in that, The catalyst mentioned in step two is sodium acetate.

7. The method for efficiently preparing ethyl torreya sylvestris acid according to claim 1, characterized in that, The antioxidants mentioned in step three are vitamin E and rosemary extract, with a mass ratio of (4-6):(1-3).

8. Ethyl pine ester nanoparticles prepared by the method according to any one of claims 1-7.

9. The application of ethyl torreya syrup nanoparticles according to any one of claims 1-8 in gel fructose, characterized in that, Includes the following steps: Step 1: Mix water, sorbitol, maltitol, pectin, citrus fiber, agar, ethyl torreya syringate nanoparticles, citrus flavoring, erythritol, and potassium citrate in a mass ratio of (45-55):(30-40):(15-25):(4-6):(8-12):(2-4):(40-45):(0.8-1.2):(0.2-0.4):(0.4-0.6) and stir to obtain a gel solution; Step 2: After injecting the gel solution into the mold, cool it and refrigerate it at 4-8℃ for 45-50 hours to obtain gel candy.

10. The application of ethyl torreya syringate nanoparticles according to any one of claims 1-8 in soft capsules, characterized in that, Includes the following steps: Step 1: Mix and stir ethyl pine ester nanoparticles, beeswax and soybean lecithin in a mass ratio of (90-95):(4-6):(2-4) to obtain adhesive solution 1; Step 2: Mix gelatin, glycerin and water in a mass ratio of (35-45):(15-20):(40-45) and stir to obtain gel solution 2; Step 3: Mix adhesive solution 1 and adhesive solution 2 at a mass ratio of (1-1.2):1, and then encapsulate and cure them sequentially to obtain ethyl torreya pine ester soft capsules.

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