Method and equipment for preparing aronia melanocarpa puree by supercritical carbon dioxide extraction process

Abstract

The invention discloses a method and equipment for preparing aronia melanocarpa primary pulp through a supercritical carbon dioxide extraction technology, and aims to solve the problem that an existing technology is insufficient in adaptability. The method comprises the following steps: S1, pretreating raw materials, cleaning and sorting fresh aronia melanocarpa fruits, destroying cell walls through physical field cooperation and composite enzymatic hydrolysis, terminating enzyme activity at low temperature, and drying and crushing to obtain powder; s2, polarity gradient modification: filling the powder into a kettle, and injecting a modifier containing high-polarity, medium-polarity and bridging components to improve the solubility of anthocyanin; s3, gradient pressure extraction: after low-pressure impurity removal, extracting active ingredients at high pressure; s4, separation and purification: performing multi-stage decompression separation and refined filtration to obtain a high-purity extracting solution; and S5, post-treatment, low-temperature concentration and residue removal, antioxidant blending, low-temperature sterilization and aseptic packaging. The equipment comprises a pretreatment unit, an extraction unit and the like, and a split-flow spraying, composite stirring and turbulent flow structure is arranged in an extraction kettle. The anthocyanin release and retention rate is increased, impurities and residues are reduced, the process is green and mature, and the high activity and purity of the primary pulp are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of natural product extraction technology, and in particular to a method and equipment for preparing aronia berry puree using supercritical carbon dioxide extraction. Background Technology

[0002] Aronia berries are rich in anthocyanins, polyphenols, and other active ingredients, and the demand for their pulp is increasing due to its natural health benefits and high nutrient content. However, the current mainstream processes for preparing aronia berry pulp have significant technological shortcomings.

[0003] Among them, the cold pressing method only extracts through physical pressing, resulting in insufficient cell wall disruption and a release rate of only 40-50% for active ingredients such as anthocyanins. In addition, the product has a high content of impurities and poor quality stability. Although the traditional solvent extraction method can improve the yield, there is a risk of organic solvent residue, and the high-temperature concentration process will cause the degradation of heat-sensitive components, with anthocyanin retention rate of less than 70%.

[0004] While existing supercritical carbon dioxide (SC-CO2) extraction technologies offer advantages such as being environmentally friendly and operating at low temperatures, there is no mature, suitable process for preparing aristocratic berry pulp. Directly employing existing supercritical carbon dioxide extraction processes presents several problems: First, anthocyanins are polar molecules, while SC-CO2 is a non-polar fluid. Based on the principle of "like dissolves like," their compatibility is extremely poor. A single modifier can only slightly increase the polarity of carbon dioxide, failing to significantly improve anthocyanin solubility, resulting in low extraction efficiency. Second, the raw material pretreatment involves only simple crushing and drying, without targeted disruption of the pectin-cellulose complex structure of the aristocratic berry cell wall. Bound anthocyanins remain tightly encapsulated, further limiting the yield. Third, the post-treatment process is incomplete. Separation of the modifier from the extract relies solely on simple decompression without optimizing temperature and pressure parameters, leading to incomplete residue removal. Furthermore, the sterilization and concentration processes are not tailored to the characteristics of heat-sensitive components; high temperatures cause additional loss of active ingredients, and a complete process suitable for the pulp form has not been established, making it impossible to directly produce high-activity, high-purity, qualified pulp.

[0005] Therefore, there is an urgent need for a mature supercritical carbon dioxide extraction process for extracting argan fruit pulp. Summary of the Invention

[0006] The main objective of this invention is to provide a method and equipment for preparing aronia berry pulp using supercritical carbon dioxide extraction, aiming to solve the problem of insufficient adaptability of existing aronia berry pulp preparation processes and existing supercritical carbon dioxide extraction technology.

[0007] To achieve the above objectives, this invention proposes a method for preparing aronia berry puree using supercritical carbon dioxide extraction, comprising the following steps: S1. Raw material pretreatment: After cleaning and sorting the fresh aronia berries, the pectin-cellulose complex structure of the cell wall is destroyed by physical field synergy. Then, a complex enzyme targeting the complex structure is added for enzymatic hydrolysis. After enzymatic hydrolysis, the enzyme activity is terminated by low temperature treatment. After low temperature drying and pulverization, aronia berry powder is obtained. The physical field synergy is a combination of at least two physical fields used to enhance the cell wall perforation effect; the complex enzyme contains components that can degrade pectin and cellulose; S2. Polar gradient modification: The *Aralia elata* powder is loaded into a supercritical extraction vessel and a polar gradient composite modifier is injected. The modifier contains a high-polarity component, a medium-polarity component, and a bridging component. The polar gradient is used to match the amphoteric structure of anthocyanins to improve their solubility in supercritical carbon dioxide. S3. Gradient pressure extraction: Supercritical carbon dioxide fluid is introduced into the extraction vessel. Non-polar impurities are selectively extracted under low pressure conditions. Then, dynamic extraction is performed by increasing the pressure to dissolve active ingredients such as anthocyanins in a directional manner, resulting in a supercritical carbon dioxide mixed fluid containing active ingredients. S4. Separation and purification: The mixed fluid in step S3 is separated by multi-stage depressurization to collect the crude extract of active ingredients. Then, fine filtration is used to remove the fine impurities in the crude extract to obtain a high-purity extract. S5. Low-temperature stabilization post-treatment: The high-purity extract from step S4 is concentrated at low temperature and the modifier residue is thoroughly removed. After being mixed with a natural antioxidant system, it is sterilized at low temperature and aseptically packaged to obtain the argan puree.

[0008] In one possible implementation, the synergistic effect of the physical fields in step S1 is a combination of ultrasound and pressure field. First, the cavitation effect of ultrasound generates microcracks in the cell wall, and then the instantaneous change of the pressure field destroys the connection structure between cells to expand the cracks.

[0009] In one possible implementation, the complex enzyme is a combination of pectinase, cellulase and hemicellulase, and the low-temperature treatment is an ice-water bath cooling to quickly terminate enzymatic hydrolysis and avoid excessive dissolution of pectin.

[0010] In one possible implementation, the highly polar component in step S2 is water, the medium polar component is ethanol, and the bridging component is a food-grade polyol.

[0011] In one possible implementation, the extraction under low pressure conditions in step S3 is static extraction, and the extraction under high pressure conditions is dynamic extraction, achieving selective separation of nonpolar impurities and polar active ingredients through pressure gradient changes.

[0012] In one possible implementation, the deep removal of modifier residues in step S5 employs molecular distillation technology, the natural antioxidant system is a composite system of natural plant extracts and vitamin C, and the low-temperature sterilization is ultra-high pressure sterilization or low-temperature pasteurization to avoid thermal degradation of active ingredients.

[0013] To achieve the above process, the present invention also provides an apparatus for preparing aristolochic acid strawberry pulp using supercritical carbon dioxide extraction, comprising a raw material pretreatment unit, a supercritical extraction unit, a separation and purification unit, and a post-treatment unit; the supercritical extraction unit includes a supercritical extraction vessel, which has a tank-like structure and is equipped with a modifier diversion spray structure, a composite stirring mechanism, and a fixed-angle turbulence structure inside; the modifier diversion spray structure is connected to an external modifier supply device; it also includes a drive unit located at the top of the supercritical extraction vessel, a supercritical carbon dioxide inlet located at the bottom of the supercritical extraction vessel, and a mixed fluid outlet located at the top of the supercritical extraction vessel.

[0014] In one possible implementation, the modifier diversion spray structure includes two annular spray pipes, each connected to an external modifier supply device. The two spray pipes are coaxially and spaced apart on the inner wall of the supercritical extraction vessel. Atomizing nozzles are uniformly connected to the spray pipes circumferentially. The atomizing nozzles located on the upper layer are inclined downwards into the supercritical extraction vessel, while the atomizing nozzles located on the lower layer are inclined radially and downwards into the supercritical extraction vessel.

[0015] In one possible implementation, the composite stirring mechanism includes a stirring shaft with a drive unit fixedly connected to its top. An upper layer of blades and a lower layer of blades are fixed axially along the stirring shaft. The upper layer of blades consists of several arc-shaped blades that intersect vertically. The blades are bent towards the bottom of the vessel along their length and are inclined to the horizontal plane. The edges of the blades are serrated, and the side of the blade facing the direction of rotation has a micro-protrusion. A guide groove is formed at the root of the blade, extending outward along the length of the blade with its opening facing the same direction as the blade's rotation. The lower layer of blades has a spiral structure. A sealing assembly is provided at the connection between the stirring shaft and the supercritical extraction vessel.

[0016] In one possible implementation, the fixed-angle turbulence structure includes several arc-shaped turbulence plates, which are evenly distributed circumferentially along the inner wall of the supercritical extraction vessel and tilted inward to break the stable flow field formed by stirring.

[0017] Compared with the prior art, the beneficial effects of this application are as follows: 1. Significantly improves extraction efficiency and product purity: By combining physical field synergy with compound enzymes to target cell wall destruction, and by improving the compatibility of anthocyanins with supercritical carbon dioxide through polar gradient modification, coupled with gradient pressure extraction and fine filtration purification, the anthocyanin release rate can be effectively improved and the impurity content of the pulp can be greatly reduced, solving the pain points of low yield and poor purity of traditional processes.

[0018] 2. Maximize the retention of active ingredients: The entire process is carried out at low temperatures, combined with molecular distillation for deep residue removal, low-temperature sterilization and a natural antioxidant system, avoiding organic solvent residues and degradation of heat-sensitive components. The anthocyanin retention rate is increased by more than 20% compared with traditional solvent extraction methods, ensuring the high activity characteristics of the original pulp.

[0019] 3. Green, safe, and mature technology: No organic solvents are used, meeting the needs of natural health; the process covers the entire process from raw material pretreatment to finished product packaging. The equipment enhances three-phase mixing through diversion spraying, compound stirring, and turbulence structure, adapting to the specific needs of aronia berry puree preparation and solving the problem of insufficient adaptability of existing supercritical carbon dioxide extraction technology.

[0020] 4. Improve product stability: The synergistic effect of enzymatic hydrolysis termination, selective separation of impurities, and antioxidant formulation reduces batch fluctuations in pulp, extends shelf life, and solves the defects of unstable quality in cold pressing. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0022] Figure 1 This is a process step diagram of the present invention; Figure 2 This is a process flow diagram of the present invention; Figure 3 This is a device connection block diagram of the present invention; Figure 4 This is a connection structure diagram of the supercritical extraction vessel of the present invention; Figure 5 This is a cross-sectional view of the supercritical extraction vessel of the present invention; Figure 6 This is a three-dimensional structural diagram of the supercritical extraction vessel of the present invention; Figure 7 This is a perspective view of the composite stirring mechanism of the supercritical extraction vessel of the present invention; Figure 8 This is a perspective view of the upper blade of the present invention; Figure 9for Figure 8 Enlarged view at point A; Explanation of icon numbers: 100. Raw material pretreatment unit; 200. Supercritical extraction unit; 300. Separation and purification unit; 310. Primary separator; 320. Secondary separator; 330. Ceramic membrane filter; 340. Carbon dioxide purification and recovery system; 400. Post-treatment unit; 1. Supercritical extraction vessel; 2. Modifier supply system; 3. Temperature control system; 4. Vessel cover; 5. Drive unit; 6. Sealing assembly; 7. Modifier diversion spray structure; 70. Spray pipe; 71. Atomizing nozzle; 8. Composite stirring mechanism; 80. Stirring shaft; 81. Upper impeller; 810. Blade; 811. Micro-convex ridge; 812. Guide channel; 82. Lower impeller; 9. Arc-shaped baffle; 10. High-pressure plunger pump.

[0023] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0025] Example 1 See attached document Figures 1-2 As shown, this invention proposes a method for preparing argan strawberry puree using supercritical carbon dioxide extraction, comprising the following steps: S1. Raw Material Pretreatment: The fresh arugula are cleaned and sorted. First, the fresh fruit is placed in an air bubble washing machine, through which 20-25℃ clean water is introduced. The bubble generator is turned on, and the fruit is washed at a pressure of 0.2-0.3 MPa for 3-5 minutes. The bubbles tumble and remove surface dirt and impurities. After removal, the fruit is manually sorted to remove rotten, unripe, and damaged fruit, retaining only the qualified fresh fruit. This step removes over 98% of exogenous impurities from the raw material, ensuring that the proportion of qualified fresh fruit is ≥80%. The principle is that the gentle impact of the bubbles tumbling in the water removes surface impurities while avoiding damage to the fruit skin from the high-pressure water flow. Manual sorting further precisely removes unqualified fruit, ensuring uniform raw material quality from the source and laying the foundation for stable subsequent processes.

[0026] Subsequently, a synergistic physical field effect was employed to disrupt the pectin-cellulose complex structure of the cell wall. This synergistic effect consisted of a combination of ultrasonic waves and a pressure field, achieved using an ultrasonic cleaner and a high-pressure homogenizer commonly used in the food industry. First, qualified fresh fruit was transferred to an ultrasonic extraction tank, and an equal mass of 20°C deionized water was added. The ultrasonic equipment was then turned on, with a frequency set to 20-30 kHz and a power of 800-1200 W, and treatment continued for 10-15 minutes. The cavitation effect created by the propagation of ultrasound in the liquid generated dense, micron-sized microcracks on the cell wall surface, simultaneously loosening the bonds between pectin and cellulose. This operation resulted in uniformly distributed microcracks on the cell wall surface, achieving an initial cell wall damage rate of over 55%. The principle is that when ultrasound propagates in a liquid medium, it generates countless tiny bubbles. The energy released during the rapid generation, expansion, and rupture of these bubbles creates localized impact forces that act on the cell wall surface, forming microcracks. Simultaneously, the vibrational energy loosens the bonds between pectin and cellulose, reducing the structural strength of the cell wall.

[0027] After ultrasonic treatment, the fruit pulp is pumped into a high-pressure homogenizer, with the working pressure set to 40 to 60 MPa. Under high pressure, the pulp passes through the tiny gaps of the homogenizing valve. The sudden pressure drop, high-speed impact, and shearing action further expand the microcracks in the cell walls, simultaneously breaking down some intact cells, achieving a synergistic physical effect in cell wall disruption. This step can increase the total cell wall damage rate to over 88%, a 30% improvement compared to ultrasonic treatment alone. The principle is that when the high-pressure pulp passes through the homogenizing valve gaps at extremely high speed, a sudden pressure drop occurs (from 40-60 MPa to atmospheric pressure), and the pressure difference between the inside and outside of the cells causes cell wall rupture. Simultaneously, the impact and shearing action of the high-speed fluid against the valve further expands the microcracks formed by ultrasonic pretreatment. These two physical actions work synergistically to achieve efficient cell wall disruption while avoiding excessive disruption that could lead to impurity leaching.

[0028] Next, a complex enzyme targeting this complex structure is added for enzymatic hydrolysis. The complex enzyme is a combination of pectinase, cellulase, and hemicellulase. The fresh fruit, after physical field treatment, is first crushed to a particle size of 3 to 5 mm using a crusher and transferred to an enzymatic hydrolysis tank. Deionized water is added at a material-to-liquid ratio of 1:3 to 1:5. The pH of the system is adjusted to 4.0 to 5.0 with citric acid, and the temperature is raised to 42 to 48°C. The complex enzyme is added at a ratio of 0.8% to 1.2% of the fresh fruit weight, with the mass ratio of pectinase, cellulase, and hemicellulase being 2:1:0.5 to 3:1:1. Then, the stirring device is turned on and stirred at a speed of 80 to 120 rpm for 40 to 60 minutes. This step stabilizes the degradation rate of the pectin-cellulose complex at around 92% and increases the release rate of bound anthocyanins to 96%. The principle is that the pectinase in the complex enzyme specifically degrades the pectin component in the cell wall, while the cellulase and hemicellulase target and decompose cellulose and hemicellulose respectively. The three work synergistically to break down the complex network structure of the cell wall. The optimal conditions for the complex enzyme to function are a pH of 4.0 to 5.0 and a temperature of 42 to 48°C, which maximizes enzyme activity. Stirring ensures that the enzyme solution and the fruit pulp are in full contact, avoiding uneven local enzymatic hydrolysis.

[0029] After enzymatic hydrolysis, enzyme activity is terminated through low-temperature treatment. This low-temperature treatment involves rapidly transferring the solution to an ice-water bath at 0-4°C and cooling it to below 10°C within 15 minutes to quickly terminate the enzymatic hydrolysis and prevent excessive pectin dissolution. This operation instantly inhibits the catalytic activity of the enzyme, reducing excessive pectin dissolution by more than 40%. The principle is that enzyme activity depends on a suitable temperature; the low-temperature environment of 0-4°C rapidly destroys the enzyme's spatial structure, causing it to lose its catalytic ability, thereby terminating the enzymatic hydrolysis reaction and preventing the continuous degradation of pectin that would lead to turbidity in the extract.

[0030] The liquid material is then fed into a vacuum freeze dryer, with the pre-freezing temperature set to -35 to -45°C, the pre-freezing time to 1.5 to 2.5 hours, the sublimation temperature to 25 to 35°C, and the vacuum degree to ≤10Pa. The material is dried until the moisture content is ≤5%. The dried material is then pulverized using a planetary ball mill and passed through an 80 to 120 mesh sieve to obtain *Aristolochic acid* powder with a particle size ≤150μm, which is then sealed for later use. This step ensures an anthocyanin retention rate of ≥98% and a powder agglomerate content of ≤3%. The principle is that vacuum freeze drying pre-freezes the liquid material into a solid state, then sublimates the water directly from the solid to the gaseous state under vacuum, avoiding thermal degradation of anthocyanins throughout the process. The pulverizing effect of the planetary ball mill forms a fine powder after drying, increasing the specific surface area and creating conditions for sufficient contact with supercritical carbon dioxide and modifiers.

[0031] S2. Polarity Gradient Modification: The *Aristolochia debilis* powder obtained in step S1 is loaded into a supercritical extraction vessel. The loading volume is controlled to be 60% to 70% of the effective volume of the vessel to avoid overfilling and affecting the mixing effect. The vessel lid is closed and the flange bolts are tightened. Compressed air is introduced into the vessel to 25 to 35 MPa, and the pressure is maintained for 8 to 12 minutes for an airtightness test to ensure that the leakage rate is <0.005 MPa / h. This operation can ensure the stability of the high-pressure environment during the extraction process and avoid process fluctuations and safety risks caused by supercritical carbon dioxide leakage. The principle is to simulate the extraction pressure environment by introducing high-pressure compressed air. If there is a defect in the vessel seal, the pressure will drop significantly, thus verifying the sealing performance.

[0032] Subsequently, a polar gradient composite modifier is injected. The modifier comprises a high-polarity component, water, a medium-polarity component (ethanol), and a bridging component (food-grade polyol), prepared in a volume ratio of 5:4:1 to 6:3:1. After thorough mixing, the mixture is transferred to the modifier supply tank. The supply pump is started, and the modifier is injected at a rate of 0.1 to 0.3 mL / min through a double-layer split-flow spray structure inside the tank. The upper nozzle is tilted 30 to 45° towards the upper part of the material layer, and the lower nozzle is tilted 45 to 60° towards the lower part of the material layer and radially. Spraying lasts for 5 to 8 minutes to ensure uniform wetting of the powder with the modifier. The polar gradient is used to match the amphoteric structure of anthocyanins to improve their solubility in supercritical carbon dioxide. The total amount of modifier used is 15% to 25% of the mass of the protea powder. This step can increase the solubility of anthocyanins in supercritical carbon dioxide by more than 65% compared to modification with ethanol alone. The principle is that anthocyanins are amphoteric molecules. Water (highly polar) in the modifier can form hydrogen bonds with the polar groups of anthocyanins, while ethanol (medium polar) acts as a transitional link. The polyol (bridging component) builds a polar bridge between anthocyanins and nonpolar supercritical carbon dioxide through its own structure, forming a continuous polar gradient that precisely matches the amphoteric structure of anthocyanins. The double-layer spray structure allows the modifier to uniformly cover the powder surface, forming a uniform modifier film, ensuring that each powder particle can fully contact the modifier.

[0033] S3. Gradient Pressure Extraction: Supercritical carbon dioxide fluid is introduced into the extraction vessel, initially entering a static extraction stage under low pressure. The carbon dioxide refrigeration system is activated to cool the liquid carbon dioxide to -5 to 0°C. Supercritical carbon dioxide is then introduced into the vessel via a high-pressure plunger pump, increasing the pressure to 12 to 18 MPa and the temperature to 35 to 45°C. The stirring motor is then turned on and stirred at a low speed of 60 to 100 rpm for 25 to 35 minutes, selectively extracting non-polar impurities. This step can remove more than 82% of non-polar impurities such as waxes and fats. The principle is that the solubility of supercritical carbon dioxide is pressure-dependent; at low pressure (12 to 18 MPa), it has a strong solubility for non-polar substances but a weak solubility for highly polar anthocyanins. Low-speed stirring allows supercritical carbon dioxide to penetrate evenly in the material layer, fully dissolving non-polar impurities and achieving preliminary separation of impurities from active ingredients.

[0034] Then, a dynamic extraction stage under high pressure is entered. The carbon dioxide pressure is increased to 30 to 40 MPa, the temperature to 40 to 50 °C, and the stirring speed to 200 to 300 rpm by a PLC system. At the same time, the modifier supply pump is restarted to continuously replenish the modifier at a rate of 0.6 to 1.0 mL / min. This state is maintained for 50 to 70 minutes to directionally dissolve active ingredients such as anthocyanins, resulting in a supercritical carbon dioxide mixed fluid containing active ingredients. The selective separation of non-polar impurities and polar active ingredients is achieved by changing the pressure gradient. This step enables anthocyanin extraction to reach 97%, which is 1.1 times higher than the traditional cold pressing method. The principle is that the density of supercritical carbon dioxide increases under high pressure (30 to 40 MPa), significantly enhancing its solubility and greatly improving its ability to dissolve anthocyanins. High-speed stirring creates a strong turbulent environment, which, together with the shearing action of the upper blades, breaks up powder agglomerates. The lower propeller blades drive the material to axially circulate, so that the powder, modifier, and supercritical carbon dioxide form a stable three-phase mixture system. The continuously replenished modifier further enhances the solubility of anthocyanins, achieving efficient directional extraction.

[0035] S4. Separation and Purification: The mixed fluid from step S3 undergoes multi-stage pressure reduction separation. It first enters the primary separator, where the pressure is set to 8-12 MPa and the temperature to 25-35°C. Most of the carbon dioxide releases anthocyanins due to the pressure reduction, forming a crude extract. The carbon dioxide is then discharged from the top into the secondary separator, where the pressure is set to 3-6 MPa and the temperature to 20-30°C. The remaining small amount of anthocyanins completely precipitates out and is combined with the crude extract collected in the primary separator. The gaseous carbon dioxide is purified and recycled, with a recovery rate ≥90%. This step can achieve an active ingredient recovery rate ≥98% while reducing production costs. The principle is that pressure reduction leads to a decrease in the density of supercritical carbon dioxide, resulting in a loss of solubility and the precipitation of active ingredients such as anthocyanins. The multi-stage separation design ensures full recovery of active ingredients and reduces losses. The purified gaseous carbon dioxide can be recompressed into a supercritical state for recycling, achieving efficient resource utilization.

[0036] After collecting the crude extract of active ingredients, fine impurities are removed by fine filtration. A ceramic membrane filter is used, with a membrane pore size of 0.2 to 0.45 μm, an operating pressure of 0.2 to 0.4 MPa, and a temperature of 20 to 30 °C. This filters out fine powder impurities and undegraded pectin, resulting in a high-purity extract. This step ensures that the impurity content of the extract is ≤0.7% and the turbidity is ≤18 NTU. The principle is that the ceramic membrane has a uniform microporous structure, and its sieving effect can retain fine impurities and undegraded pectin with particle sizes larger than the membrane pore size, while small molecule active ingredients such as anthocyanins can pass through the membrane pores smoothly, achieving solid-liquid separation and improving the purity and clarity of the extract.

[0037] S5. Low-Temperature Stabilization Post-Treatment: The high-purity extract from step S4 is concentrated at low temperature to remove residual modifiers. First, the extract is transferred to a vacuum low-temperature concentration device, with the temperature set at 40 to 50°C and the vacuum degree ≤20Pa, concentrating it to 1 / 3 to 1 / 5 of its original volume. For deep removal of residual modifiers, molecular distillation technology is used. The concentrate is sent to a molecular distillation apparatus, with the evaporation temperature set at 50 to 60°C and the operating pressure ≤1Pa, efficiently removing residual modifiers to <0.005%. This step can increase the anthocyanin concentration in the concentrate by 3 to 5 times, and the residual modifiers are far below the national standard detection limit. The principle is that vacuum low-temperature concentration uses the vacuum environment to lower the boiling point of the extract, achieving rapid dehydration at low temperatures and avoiding thermal degradation of anthocyanins. Molecular distillation utilizes the difference in the mean free path of different molecules. Under high vacuum and low temperature conditions, modifier molecules, due to their shorter mean free path, are more likely to reach the condensation surface and condense and separate, while anthocyanin molecules remain in the concentrate, achieving precise removal of residues.

[0038] Subsequently, a natural antioxidant system is added, which is a complex of natural plant extracts and vitamin C, mixed at a mass ratio of 2:1 to 3:1, with a total addition of 0.1% to 0.3% of the concentrate mass. The mixture is then transferred to a mixing vessel and stirred at 120 to 180 rpm for 15 to 25 minutes until homogeneous. This process reduces the anthocyanin oxidation rate by more than 75%, extending the product's shelf life to over 12 months. The principle is that the natural plant extracts and vitamin C have a synergistic antioxidant effect, effectively scavenging free radicals within the system and inhibiting the oxidative damage of anthocyanin molecules. Stirring ensures that the antioxidants are evenly dispersed in the concentrate, guaranteeing that each portion of the extract is adequately protected.

[0039] After preparation, the product undergoes low-temperature sterilization, which can be either ultra-high pressure sterilization or low-temperature pasteurization. When using ultra-high pressure sterilization, set the pressure to 300-400 MPa and hold for 4-6 minutes. When using low-temperature pasteurization, set the temperature to 60-70℃ and hold for 10-15 minutes to avoid thermal degradation of active ingredients. This step ensures that the total number of microorganisms after sterilization is ≤5 CFU / mL, and the anthocyanin retention rate is ≥95%. The principle is that ultra-high pressure sterilization destroys the cell membrane structure and enzyme activity of microorganisms through high pressure, achieving sterilization, while maintaining low temperatures throughout the process to prevent damage to anthocyanins. Low-temperature pasteurization, on the other hand, kills harmful microorganisms in the extract by holding it at a lower temperature for a certain period of time, while avoiding high temperatures that could lead to degradation of active ingredients, ensuring product hygiene and safety while preserving core nutrients.

[0040] Example 2 S1. Raw Material Pretreatment: Select 100 kg of fresh arugula and put them into a bubble washing machine. Pour in 22℃ water and turn on the bubble generator to wash at 0.25 MPa pressure for 4 minutes. After washing, manually sort out rotten, unripe, and damaged fruits, retaining 82 kg of qualified fresh fruit. Transfer the qualified fresh fruit to an ultrasonic extraction tank, add 82 kg of 20℃ deionized water, turn on the ultrasonic equipment, set the frequency to 25 kHz and the power to 1000 W, and continue processing for 12 minutes. After ultrasonic treatment, pump the pulp into a high-pressure homogenizer, set the working pressure to 50 MPa, and complete the homogenization process. The fruit pulp was then crushed to a particle size of 4 mm using a crusher and transferred to an enzymatic hydrolysis tank. 246 kg of deionized water was added, and the pH was adjusted to 4.5 with citric acid. The temperature was raised to 45°C, and a compound enzyme was added at 1.0% of the fresh fruit weight, with a pectinase:cellulase:hemicellulase mass ratio of 2.5:1:0.8. The stirring device was turned on at 100 rpm, and enzymatic hydrolysis was carried out for 50 minutes. After enzymatic hydrolysis, the solution was quickly transferred to a 2°C ice-water bath and cooled to 8°C within 12 minutes to terminate enzyme activity. The solution was then sent to a vacuum freeze dryer, with the pre-freezing temperature set to -40°C, pre-freezing time 2 hours, sublimation temperature 30°C, and vacuum degree 8 Pa, until the moisture content reached 4%. The dried material was then pulverized using a planetary ball mill and passed through a 100-mesh sieve to obtain 10.5 kg of aronia berry powder, which was sealed for later use.

[0041] S2. Polar Gradient Modification: 10.5 kg of *Aristolochia debilis* powder was loaded into a 50 L supercritical extraction vessel, filling 65% of the vessel's effective volume. The vessel lid was closed and the flange bolts tightened. Compressed air was introduced into the vessel to 30 MPa, and the pressure was maintained for 10 minutes for an airtightness test. The leakage rate was 0.003 MPa per hour. A polar gradient composite modifier was prepared at a volume ratio of 5.5:3.5:1, consisting of 5.775 L of water, 3.675 L of ethanol, and 1.05 L of food-grade propylene glycol. After thorough mixing, the mixture was transferred to the modifier supply tank. The supply pump was started, and the modifier was injected at a rate of 0.2 mL per minute through the double-layer diversion spray structure inside the vessel. The upper nozzle was tilted 35 degrees towards the upper part of the material layer, and the lower nozzle was tilted 50 degrees towards the lower part of the material layer and radially. Spraying was carried out for 6 minutes, with a total modifier usage of 2.1 kg.

[0042] S3. Gradient Pressure Extraction: Supercritical carbon dioxide fluid is introduced into the extraction vessel, and the carbon dioxide refrigeration system is activated to cool the liquid carbon dioxide to -3°C. Supercritical carbon dioxide is then introduced into the vessel via a high-pressure plunger pump, pressurizing to 15 MPa and heating to 40°C. The stirring motor is then turned on and stirred at a low speed of 80 rpm for 30 minutes for static extraction. Subsequently, the carbon dioxide pressure is increased to 35 MPa and the temperature to 45°C via the PLC system, while the stirring speed is increased to 250 rpm. Simultaneously, the modifier supply pump is restarted, continuously replenishing the modifier at a rate of 0.8 mL per minute. This process is maintained for 60 minutes for dynamic extraction, yielding a supercritical carbon dioxide mixture containing active ingredients.

[0043] S4. Separation and Purification: The mixed fluid undergoes multi-stage vacuum separation. First, it enters the primary separator at a pressure of 10 MPa and a temperature of 30°C. Most of the carbon dioxide releases anthocyanins, forming a crude extract. The carbon dioxide is then discharged from the top into the secondary separator at a pressure of 5 MPa and a temperature of 25°C. The remaining small amount of anthocyanins completely precipitates out and is combined with the crude extract collected in the primary separator, yielding 18.5 liters of crude extract. The gaseous carbon dioxide is purified and recycled, with a recovery rate of 92%. After collecting the active ingredient crude extract, it undergoes fine filtration through a ceramic membrane filter at a pore size of 0.3 μm, an operating pressure of 0.3 MPa, and a temperature of 25°C to retain fine powder particles. S5. Low-Temperature Stabilization Post-Processing: The high-purity extract was transferred to a vacuum low-temperature concentration device, set at 45℃ and 15Pa, and concentrated to 1 / 4 of its original volume, yielding 4.3 liters of concentrate. The concentrate was then sent to a molecular distillation apparatus, set at 55℃ and 0.8Pa, to thoroughly remove residual modifiers. Subsequently, a natural antioxidant system was added, consisting of natural plant extracts and vitamin C mixed at a mass ratio of 2.5:1, with a total addition amount of 0.2% of the concentrate mass. This mixture was then transferred to a mixing vessel and stirred at 150 rpm for 20 minutes until homogeneous. After mixing, ultra-high pressure sterilization was performed at 350 MPa for 5 minutes to obtain the final product, *Aristolochia debilis* puree. Example 3 S1. Raw Material Pretreatment: Select 100 kg of fresh arugula and put them into an air bubble washing machine. Pour in 23℃ water and turn on the bubble generator to wash at 0.28 MPa pressure for 5 minutes. After washing, manually sort out rotten, unripe, and damaged fruits, retaining 83 kg of qualified fresh fruit. Transfer the qualified fresh fruit to an ultrasonic extraction tank, add 83 kg of 20℃ deionized water, turn on the ultrasonic equipment, set the frequency to 28 kHz and the power to 1100 W, and continue processing for 13 minutes. After ultrasonic treatment, pump the pulp into a high-pressure homogenizer, set the working pressure to 55 MPa, and complete the homogenization process. Then, use a crusher to crush the pulp to a particle size of 3 mm, transfer it to an enzymatic hydrolysis tank, add 332 kg of deionized water, adjust the pH of the system to 4.8 with citric acid, raise the temperature to 46℃, add a compound enzyme at 1.1% of the fresh fruit weight, with a pectinase, cellulase, and hemicellulase mass ratio of 3:1:1, turn on the stirring device, and stir at 110 rpm for 55 minutes of enzymatic hydrolysis. After enzymatic hydrolysis, the solution was quickly transferred to a 1°C ice-water bath and cooled to 7°C within 10 minutes to terminate enzyme activity. The solution was then fed into a vacuum freeze dryer, with the pre-freezing temperature set to -42°C, pre-freezing time to 2.2 hours, sublimation temperature to 32°C, and vacuum degree to 6Pa, until the moisture content reached 3.5%. The dried material was then pulverized using a planetary ball mill and passed through a 110-mesh sieve to obtain 10.8 kg of *Aristolochia debilis* powder, which was sealed for later use.

[0044] S2. Polar Gradient Modification: 10.8 kg of *Ardisia crenata* powder was loaded into a 50 L supercritical extraction vessel, filling 68% of the vessel's effective volume. The vessel lid was closed and the flange bolts tightened. Compressed air was introduced into the vessel to 32 MPa, and the pressure was maintained for 11 minutes for an airtightness test. The leakage rate was 0.002 MPa per hour. A polar gradient composite modifier was prepared at a volume ratio of 6:3:1, consisting of 6.48 L of water, 3.24 L of ethanol, and 1.08 L of food-grade propylene glycol. After thorough mixing, the mixture was transferred to the modifier supply tank. The supply pump was started, and the modifier was injected at a rate of 0.25 mL per minute through the double-layer diversion spray structure inside the vessel. The upper nozzle was tilted 40 degrees towards the upper part of the material layer, and the lower nozzle was tilted 55 degrees towards the lower part of the material layer and radially. Spraying was carried out for 7 minutes, with a total modifier usage of 2.7 kg.

[0045] S3. Gradient Pressure Extraction: Supercritical carbon dioxide fluid is introduced into the extraction vessel, and the carbon dioxide refrigeration system is activated to cool the liquid carbon dioxide to -2°C. Supercritical carbon dioxide is then introduced into the vessel via a high-pressure plunger pump, pressurizing to 16 MPa and heating to 42°C. The stirring motor is then turned on and stirred at a low speed of 90 rpm for 32 minutes for static extraction. Subsequently, the carbon dioxide pressure is increased to 38 MPa and the temperature to 48°C via the PLC system, while the stirring speed is increased to 280 rpm. Simultaneously, the modifier supply pump is restarted, continuously replenishing the modifier at a rate of 0.9 mL per minute. This process is maintained for 65 minutes for dynamic extraction, yielding a supercritical carbon dioxide mixture containing active ingredients.

[0046] S4. Separation and Purification: The mixed fluid is subjected to multi-stage vacuum separation. First, it enters the primary separator at a pressure of 11 MPa and a temperature of 32°C. Most of the carbon dioxide releases anthocyanins, forming a crude extract. The carbon dioxide is then discharged from the top into the secondary separator at a pressure of 4 MPa and a temperature of 28°C. The remaining small amount of anthocyanins completely precipitates out and is combined with the crude extract collected in the primary separator, yielding 19.2 liters of crude extract. The gaseous carbon dioxide is purified and recycled, with a recovery rate of 93%. After collecting the crude extract of active ingredients, it is finely filtered through a ceramic membrane filter at a pore size of 0.25 μm, an operating pressure of 0.35 MPa, and a temperature of 28°C. Fine powder impurities and undegraded pectin are retained, yielding 18.1 liters of high-purity extract.

[0047] S5. Low-Temperature Stabilization Post-Processing: The high-purity extract was transferred to a vacuum low-temperature concentration device, set at 48℃ and 12Pa, and concentrated to 1 / 5 of its original volume, yielding 3.62 liters of concentrate. The concentrate was then sent to a molecular distillation apparatus, set at 58℃ and 0.5Pa, to thoroughly remove any remaining modifiers. Subsequently, a natural antioxidant system was added, consisting of natural plant extracts and vitamin C mixed at a mass ratio of 3:1, with a total addition amount of 0.25% of the concentrate mass. This mixture was then transferred to a mixing vessel and stirred at 160 rpm for 22 minutes until homogeneous. After mixing, low-temperature pasteurization was performed at 65℃ for 12 minutes. After sterilization, the mixture was filled into 50mL sterile glass bottles using a sterile filling machine in a Class 100 clean bench, yielding 724 bottles of the finished aronia berry puree. Comparative Example: Preparation of Amaranth Fruit Puree by Traditional Solvent Extraction Method S1. Raw Material Pretreatment: Select 100 kg of fresh arugula and put them into a bubble washing machine. Pour in 22℃ water and turn on the bubble generator to wash at 0.25 MPa pressure for 4 minutes. After washing, manually sort out rotten, unripe, and damaged fruits, retaining 82 kg of qualified fresh fruits. Crush the qualified fresh fruits to a particle size of 4 mm using a crusher, transfer them to an extraction tank, add 246 kg of 70% ethanol solution, heat to 60℃, turn on the stirring device and stir at 100 rpm for 120 minutes.

[0048] S2. Filtration and Concentration: After extraction, the crude extract is filtered through a plate and frame filter to obtain 210 liters of crude extract. The crude extract is then transferred to a rotary evaporator, and the temperature is set to 75℃ and the vacuum degree to 20Pa. The extract is concentrated to 1 / 5 of the original volume to obtain 42 liters of concentrate.

[0049] S3. De-alcoholization and sterilization: The concentrate is transferred to a de-alcoholization tower, set at 80℃ and 0.05MPa, to remove residual ethanol. Then, a natural antioxidant system is added, consisting of natural plant extracts and vitamin C mixed at a mass ratio of 2.5:1, with a total addition amount of 0.2% of the concentrate mass. After thorough stirring, high-temperature sterilization is performed at 121℃ for 20 minutes to obtain the aronia berry puree. In summary, Examples 2 and 3, employing supercritical carbon dioxide extraction combined with physical field-assisted cell disruption and polar gradient modification, significantly outperformed the traditional solvent extraction method of Comparative Example 1 in terms of anthocyanin extraction rate, retention rate, and product purity. Example 3, through optimized process parameters, achieved an anthocyanin extraction rate of 98.1%, a 33.1 percentage point increase compared to Comparative Example 1; the modifier residue was only 0.002%, far lower than the 0.15% ethanol residue in Comparative Example 1; and the anthocyanin degradation rate after 30 days of accelerated storage at 37°C was only 2.1%, a 15.9 percentage point decrease compared to Comparative Example 1. This fully demonstrates the advantages of the present invention's process in improving product quality, safety, and stability.

[0050] Example 4 See attached document Figures 3-9 This embodiment, based on Embodiments 1-3, provides an apparatus for preparing aristolochic acid strawberry puree using a supercritical carbon dioxide extraction process, such as... Figures 3-4 As shown, it consists of a raw material pretreatment unit 100, a supercritical extraction unit 200, a separation and purification unit 300, and a post-treatment unit 400 connected in sequence. Each unit achieves orderly material transfer through food-grade stainless steel pipes or a closed conveyor belt.

[0051] The sealed silo of the raw material pretreatment unit 100 is connected to the inlet of the extraction vessel of the supercritical extraction unit 200 through a sealed conveying device to achieve clean feeding of the aralia powder; the mixed fluid outlet of the supercritical extraction unit 200 is connected to the inlet of the primary separator 310 of the separation and purification unit 300 through a high-pressure stainless steel pipeline to complete the export of the fluid containing active ingredients; the outlet of the ceramic membrane filter 330 of the separation and purification unit 300 is connected to the vacuum low-temperature concentration equipment of the post-treatment unit 400 through a pipeline to deliver high-purity extract; at the same time, the supercritical extraction unit 200 is also connected to the modifier supply system 2 and the carbon dioxide preparation and circulation system to ensure the stable supply and recovery of the media required for the extraction process.

[0052] Specifically, the structural equipment in the raw material pretreatment unit 100, separation and purification unit 300, post-treatment unit 400, and supercritical extraction unit 200, except for the supercritical extraction vessel 1, all adopt mature and applied equipment combinations. Therefore, the connection structure between the equipment will not be elaborated in detail.

[0053] The raw material pretreatment unit 100 adopts a combination of equipment commonly used in the food industry, mainly including a bubble washing machine, a manual sorting table, an ultrasonic device, a high-pressure homogenizer, a crusher, an enzymatic hydrolysis tank, an ice-water bath, a vacuum freeze dryer, and a planetary ball mill. Each piece of equipment is connected sequentially via food-grade conveyor belts or pipes. The outlet of the bubble washing machine connects to the manual sorting table. The sorted fresh fruit is conveyed to the ultrasonic device via a conveyor belt. The outlet of the ultrasonic device is connected to the high-pressure homogenizer via a pipe. The high-pressure homogenizer is then connected to the crusher. The crusher conveys the material to the enzymatic hydrolysis tank via a pipe. The outlet of the enzymatic hydrolysis tank connects to the ice-water bath. The ice-water bath is connected to the vacuum freeze dryer via a transfer pump. The outlet of the freeze dryer is connected to the planetary ball mill via a conveyor belt. Finally, the ball mill outputs the processed aronia powder, which is temporarily stored in a sealed silo for use in subsequent processes.

[0054] like Figure 4 As shown, the separation and purification unit 300 adopts existing industrial general equipment, mainly including a primary separator 310, a secondary separator 320 and a ceramic membrane filter 330. The mixed fluid outlet of the supercritical extraction vessel 1 is connected to the inlet of the primary separator 310 through a pipeline. The top outlet of the primary separator 310 is connected to the inlet of the secondary separator 320 through a pipeline. The bottom outlets of the two separators are all connected to the inlet of the ceramic membrane filter 330 through pipelines. The primary separator 310 and the secondary separator 320 are also connected to the carbon dioxide purification and recovery system 340 through a recovery pipeline to realize the recycling of carbon dioxide.

[0055] The post-processing unit 400 also uses mature equipment from the food industry, consisting of a vacuum low-temperature concentration device, a molecular distillation apparatus, a mixing vessel, a low-temperature sterilization device, and an aseptic filling machine. The outlet of the ceramic membrane filter 330 is connected to the vacuum low-temperature concentration device through a pipeline. The outlet of the concentration device is connected to the molecular distillation apparatus. The molecular distillation apparatus is then connected to the mixing vessel. The outlet of the mixing vessel is connected to the low-temperature sterilization device. The outlet of the sterilization device is connected to the aseptic filling machine in the Class 100 clean bench through a sterile pipeline to complete the final product packaging.

[0056] like Figures 5-6 As shown, the supercritical extraction unit 200 is the core of the entire equipment, consisting of a supercritical extraction vessel 1, a modifier supply system 2, a carbon dioxide preparation and circulation system, a drive system, and a temperature control system 3. All components are precisely connected via flanges, pipes, and sealing joints to ensure stable operation under high pressure. The core component is the supercritical extraction vessel 1, which has a vertical tank-like structure and is forged from food-grade, high-pressure-resistant, and corrosion-resistant stainless steel. The vessel wall thickness is precisely matched to the design pressure. The vessel lid 4 adopts a hydraulic quick-opening structure for easy loading and cleaning. A jacketed electric heating device is installed on the outside of the vessel, which, together with a temperature sensor and a PLC control system, enables precise temperature control within the vessel.

[0057] A drive unit 5, a variable frequency geared motor, is installed at the top center of the supercritical extraction vessel 1. It is fixedly connected to the top of the stirring shaft 80 inside the vessel via a flexible coupling. The stirring shaft 80 extends through the vessel cover 4 into the vessel body, and its shaft diameter is adapted to the vessel volume. A sealing component 6 is installed at the connection between the shaft and the vessel cover 4. The sealing component 6 can be made of packing material. The sealing design ensures no leakage under high pressure conditions, guaranteeing operational safety and process stability. The extraction vessel is equipped with a modifier diversion spray structure 7, a composite stirring mechanism 8, and a fixed tilt angle turbulence structure. These three components work together to enhance the gas-liquid-solid three-phase mixing effect, which is a key structure for improving extraction efficiency.

[0058] The modifier diversion spray structure 7 includes two coaxial and spaced-apart annular spray pipes 70, both of which are connected to the modifier supply system 2 outside the reactor body through stainless steel branch pipes. The supply system consists of an industry-standard mixing tank, metering pump and flow meter, which can accurately control the modifier delivery rate and total amount.

[0059] The upper spray pipe 70 is welded and fixed to the upper part of the inner wall of the reactor via a stainless steel bracket. Atomizing nozzles 71 are evenly distributed around the circumference of the pipe, tilting downwards towards the inside of the reactor to ensure that the modifier droplets cover the upper part of the material layer. The lower spray pipe 70 is installed in the middle of the inner wall of the reactor, corresponding to the middle section of the material layer. It also has atomizing nozzles 71 distributed around the circumference, tilting radially and downwards towards the inside of the reactor to allow the modifier droplets to penetrate into the material layer. Both layers of nozzles are made of food-grade stainless steel, providing excellent atomization and dispersing the modifier into tiny droplets, increasing the contact area with the powder. Its working principle involves a double-layer staggered spray design, allowing the modifier droplets to cover the entire material layer from different heights and angles, avoiding uneven wetting. Combined with subsequent stirring, this ensures that a uniform modifier film forms on the surface of each powder particle. This, through the polar gradient effect, enhances the compatibility of anthocyanins with supercritical carbon dioxide, ultimately achieving a significant increase in anthocyanin solubility.

[0060] like Figures 7-9 As shown, the composite stirring mechanism 8 has an upper impeller 81 and a lower impeller 82 fixed axially along the stirring shaft 80, forming a coordinated stirring system. The upper impeller 81 consists of four arc-shaped blades 810 that are perpendicularly intersecting each other. The blades 810 are made of high-strength food-grade alloy material and are bent towards the bottom of the vessel along their length, inclined to the horizontal plane. This arc and inclined design can form a composite flow field in the axial and radial directions when rotating. When the blades 810 rotate, in the radial direction, the centrifugal force generated by the rotation of the blades 810 pushes the powder and fluid towards the vessel wall; in the axial direction, the downward-inclined arc-shaped blades drive the upper fluid to flow towards the bottom of the vessel. Combined with the circulation effect of the lower fluid replenishing upwards, the material in the vessel is mixed convectively from top to bottom, avoiding local material stagnation.

[0061] The blade 810 has a serrated edge. When the upper blade 81 rotates, the relative motion between the serrations and the fluid generates a local high-speed flow stream, forming micro-vortices. This creates a periodic shearing effect on the fluid, effectively breaking up agglomerates formed by the modifier during extraction. This significantly increases the contact area between the powder and supercritical carbon dioxide and the modifier, creating conditions for efficient anthocyanin dissolution. Simultaneously, the blade 810 has uniformly stamped micro-protrusions 811 on the side facing the direction of rotation. These protrusions are arranged parallel to the length of the blade 810, further disturbing the fluid boundary layer, enhancing turbulence, reducing mass transfer resistance, and accelerating the diffusion rate of anthocyanins from the powder interior into supercritical carbon dioxide.

[0062] Meanwhile, a guide groove 812 is provided on the upper surface of the root of each blade 810. The guide groove 812 extends outward along the length of the blade 810, and the groove opening faces the same direction as the rotation direction of the upper blade 81. When the upper blade 81 rotates, the centrifugal force it generates will collect the modified agent mist falling from the upper spray pipe 70 and guide it to the edge of the blade 810 along the groove body. This allows the mist droplets to be evenly sprayed into the surrounding powder under the action of centrifugal force, avoiding direct impact of the mist droplets on the reactor wall, which would cause adhesion and waste, or cause the mist droplets to float up due to buoyancy, resulting in a decrease in utilization rate.

[0063] Below it is a spiral lower blade 82, which can drive the material at the bottom of the vessel to circulate upwards and form a convection with the radial flow formed by the upper blade 81, thus preventing the material from accumulating at the bottom of the vessel and achieving full circulation and mixing of the material inside the vessel.

[0064] Meanwhile, the lower spiral blade 82 can be designed with a variable pitch, meaning the pitch gradually decreases from the bottom to the top. When the lower blade 82 rotates, the larger pitch at the bottom generates a stronger upward thrust, quickly lifting the powder deposited at the bottom of the vessel. The gradually decreasing pitch from the middle to the top slows down the material's upward speed, allowing the material to fully mix with the downward fluid pushed by the upper blade 81 during its ascent, forming a vigorous convection mixture. This completely prevents the material from accumulating at the bottom of the vessel due to gravity, creating a mixing dead zone, and further achieving uniform circulation of the material throughout the vessel from top to bottom.

[0065] The fixed-angle turbulence structure includes multiple arc-shaped turbulence plates 9, which are evenly distributed along the circumference of the inner wall of the extraction vessel and fixed to the inner wall of the vessel by stainless steel bolts, tilting inward at a certain angle.

[0066] When the stirring shaft 80 drives the upper blades 81 to rotate and form a stable flow field, the baffle can break the continuity of the flow field and generate local turbulence through reverse flow guidance. At the same time, it blocks the material from rotating synchronously with the blades, prolongs the residence time of the material in the reactor, enhances the contact frequency and contact time between the powder and supercritical carbon dioxide and modifier, further improves the mixing uniformity and mass transfer efficiency, and avoids the occurrence of mixing dead zones.

[0067] A supercritical carbon dioxide inlet is located on one side of the bottom of the extraction vessel, connected to an external high-pressure plunger pump 10 and a refrigeration system via a flange. The refrigeration system cools the liquid carbon dioxide to the temperature required for supercritical operation, and the high-pressure plunger pump 10 pressurizes it to a set pressure before sending it into the vessel. A mixed fluid outlet is located on the other side of the top of the vessel, connected to a separation and purification unit 300. A stainless steel filter is built into the outlet to prevent fine powder from entering subsequent pipelines and causing blockages. In addition, the supercritical extraction unit 200 is also equipped with safety devices such as pressure sensors and safety valves to ensure safe operation of the equipment under high-pressure conditions.

[0068] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components. In the description of this application, it should be understood that if terms such as "upper," "lower," "left," and "right" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the accompanying drawings are only for illustrative purposes and should not be construed as limiting this patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0069] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for preparing aronia berry puree using supercritical carbon dioxide extraction, characterized in that, Includes the following steps: S1. Raw material pretreatment: After cleaning and sorting the fresh aronia berries, the pectin-cellulose complex structure of the cell wall is destroyed by physical field synergy. Then, a complex enzyme targeting the complex structure is added for enzymatic hydrolysis. After enzymatic hydrolysis, the enzyme activity is terminated by low temperature treatment. After low temperature drying and pulverization, aronia berry powder is obtained. The physical field synergy is a combination of at least two physical fields used to enhance the cell wall perforation effect; the complex enzyme contains components that can degrade pectin and cellulose; S2, Polar gradient modification: The aralia powder is loaded into a supercritical extraction vessel (1), and a polar gradient composite modifier is injected. The modifier contains a high polar component, a medium polar component and a bridging component. The polar gradient is used to match the amphoteric structure of anthocyanins to improve their solubility in supercritical carbon dioxide. S3. Gradient pressure extraction: Supercritical carbon dioxide fluid is introduced into the extraction vessel. Non-polar impurities are selectively extracted under low pressure conditions. Then, dynamic extraction is performed by increasing the pressure to dissolve active ingredients such as anthocyanins in a directional manner, resulting in a supercritical carbon dioxide mixed fluid containing active ingredients. S4. Separation and purification: The mixed fluid in step S3 is separated by multi-stage depressurization to collect the crude extract of active ingredients. Then, fine filtration is used to remove the fine impurities in the crude extract to obtain a high-purity extract. S5. Low-temperature stabilization post-treatment: The high-purity extract from step S4 is concentrated at low temperature and the modifier residue is thoroughly removed. After being mixed with a natural antioxidant system, it is sterilized at low temperature and aseptically packaged to obtain the argan puree.

2. The method for preparing aronia berry puree using supercritical carbon dioxide extraction according to claim 1, characterized in that, The synergistic effect of the physical fields mentioned in step S1 is a combination of ultrasound and pressure field. First, the cavitation effect of ultrasound generates microcracks in the cell wall, and then the instantaneous change of the pressure field destroys the connection structure between cells to expand the cracks.

3. The method for preparing aronia berry puree using supercritical carbon dioxide extraction according to claim 1, characterized in that, The complex enzyme mentioned in step S1 is a combination of pectinase, cellulase and hemicellulase. The low-temperature treatment is an ice-water bath cooling to quickly terminate the enzymatic hydrolysis and avoid excessive dissolution of pectin.

4. The method for preparing aronia berry puree using supercritical carbon dioxide extraction according to claim 1, characterized in that, The highly polar component in step S2 is water, the medium polar component is ethanol, and the bridging component is food-grade polyol.

5. The method for preparing aronia berry puree using supercritical carbon dioxide extraction according to claim 1, characterized in that, The extraction under low pressure conditions described in step S3 is static extraction, while the extraction under high pressure conditions is dynamic extraction. The selective separation of non-polar impurities and polar active ingredients is achieved through changes in pressure gradient.

6. The method for preparing aronia berry puree using supercritical carbon dioxide extraction according to claim 1, characterized in that, The deep removal of modifier residues in step S5 is achieved using molecular distillation technology. The natural antioxidant system is a composite system of natural plant extracts and vitamin C. The low-temperature sterilization is either ultra-high pressure sterilization or low-temperature pasteurization to avoid thermal degradation of active ingredients.

7. An apparatus for preparing aronia berry puree using a supercritical carbon dioxide extraction process, for implementing the method for preparing aronia berry puree using the supercritical carbon dioxide extraction process described in any one of claims 1-5, characterized in that, It includes a raw material pretreatment unit (100), a supercritical extraction unit (200), a separation and purification unit (300), and a post-treatment unit (400); the supercritical extraction unit (200) includes a supercritical extraction vessel (1), which has a tank-like structure and is equipped with a modifier diversion spray structure (7), a composite stirring mechanism (8), and a fixed tilt angle turbulence structure inside; the modifier diversion spray structure is connected to an external modifier supply device; it also includes a drive unit (5) set at the top of the supercritical extraction vessel (1), a supercritical carbon dioxide inlet set at the bottom of the supercritical extraction vessel (1), and a mixed fluid outlet set at the top of the supercritical extraction vessel (1).

8. The apparatus for preparing aronia berry puree using a supercritical carbon dioxide extraction process according to claim 7, characterized in that, The modifier diversion spray structure (7) includes an annular spray pipe (70), and two spray pipes (70) are provided, both of which are connected to an external modifier supply device. The two spray pipes (70) are coaxial and spaced apart on the inner wall of the supercritical extraction vessel (1). The spray pipes (70) are uniformly connected with atomizing nozzles (71) in the circumferential direction. The atomizing nozzle (71) located at the upper level is inclined downward in the supercritical extraction vessel (1), and the atomizing nozzle (71) located at the lower level is inclined radially and downward in the supercritical extraction vessel (1).

9. The apparatus for preparing aronia berry puree using a supercritical carbon dioxide extraction process according to claim 7, characterized in that, The composite stirring mechanism (8) includes a stirring shaft (80) with the drive unit (5) fixedly connected to the top. The stirring shaft (80) has an upper blade (81) and a lower blade (82) fixed along the axial direction. The upper blade (81) is composed of several arc-shaped blades (810) that are perpendicularly intersecting. The blades (810) are bent towards the bottom of the vessel along the length direction and are inclined to the horizontal plane. The edges of the blades (810) are processed into a serrated structure, and the side of the blades (810) facing the rotation direction is provided with a micro-protrusion (811). A guide groove (812) is opened at the root of the blades (810). The guide groove (812) extends outward along the length direction of the blades (810) and the groove opening faces the same direction as the blade rotation direction. The lower blade (82) has a spiral structure. A sealing component (6) is provided at the connection between the stirring shaft (80) and the supercritical extraction vessel (1).

10. The apparatus for preparing aronia berry puree using a supercritical carbon dioxide extraction process according to claim 7, characterized in that, The fixed-angle turbulence structure includes several arc-shaped turbulence plates (9). The arc-shaped turbulence plates (9) are evenly distributed along the inner wall of the supercritical extraction vessel (1) and tilted inward to break the stable flow field formed by stirring.

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