Passion fruit pulp separation system and method

Abstract

The invention discloses a passion fruit pulp separation system and method, and belongs to the technical field of agricultural product processing. The system aims to solve the technical problems of incomplete separation of pulp and peel, more pulp residues, low yield, low efficiency and the like in the traditional modes of manual digging, mechanical scraping or hydraulic impact and the like. Comprising a discharging channel through which passion fruits pass one by one; the puncturing and stirring unit is arranged on the side of the discharging channel and comprises a puncturing rod piece, a stirring part arranged on the puncturing rod piece in a sleeving mode, a vibration mechanism for driving the puncturing rod piece to generate high-frequency micro vibration, a rotating mechanism for driving the puncturing rod piece to rotate and a puncturing movement mechanism for driving the whole puncturing rod piece to do linear reciprocating motion. The stirring part is configured to be radially expanded into an expanded structure from a folded state under the action of centrifugal force; and a cutting unit disposed downstream. The system is mainly used for realizing efficient and automatic separation of passion fruit pulp, remarkably improves the pulp yield and the seed integrity rate, and is suitable for deep processing processes such as subsequent pulp freeze-drying.

Description

Technical Field

[0001] This invention belongs to the field of agricultural product processing technology, specifically a passion fruit pulp separation system and method. Background Technology

[0002] In the processing of passion fruit, separating the pulp from the peel is a crucial step. Currently, several methods are used in actual production to achieve this separation, but these methods present some technical challenges.

[0003] First, traditional manual harvesting methods rely heavily on the experience and skills of the operators. Due to the lack of quantifiable operational standards, it's difficult to precisely control the force and angle used during harvesting. If forceful scraping is used to maximize pulp yield, the mesocarp (the white inner membrane) of the passion fruit is easily damaged. Conversely, if gentle handling is used to avoid damage, it's difficult to completely separate the pulp from the inner shell, resulting in more pulp residue and reduced raw material utilization. This reliance on manual labor also makes it difficult to improve production efficiency and meet the demands of large-scale production.

[0004] Secondly, purely mechanical cutting or scraping methods, such as using fixed scrapers or robotic arms to scoop, apply force from the outside of the fruit. To overcome the adhesion between the pulp and peel, especially the mesocarp, these external mechanical devices typically squeeze, cut, or shear the pulp and seeds. This directly leads to two problems: first, the seeds have a high breakage rate under mechanical force, and broken seeds mixed with the pulp affect the taste and product stability of the juice; second, the mechanical parts cannot perfectly conform to the unique internal contours of each fruit, especially the uneven inner surface, resulting in some areas of pulp not being effectively scraped and separated. The mesocarp is also prone to breakage during mechanical scraping and mixes with the pulp, affecting the purity of the pulp.

[0005] In addition, there are techniques that use water jets to extract the pulp. While this method avoids direct mechanical contact damage to some extent, it typically requires high-pressure water flow, consuming a large amount of water resources. Simultaneously, the water flow removes sugars and acids from the pulp, generating large amounts of wastewater rich in organic matter. The subsequent treatment of this wastewater increases the environmental burden and processing costs. More importantly, the introduction of water dilutes the passion fruit pulp, leading to a decrease in its inherent rich flavor and aroma intensity, thus reducing the product's value.

[0006] In conclusion, the current technical challenge in passion fruit processing is achieving efficient and thorough separation of the pulp while avoiding seed damage, preserving the original flavor of the product, and minimizing environmental impact. Simply relying on external mechanical force or introducing water flow has significant limitations. Summary of the Invention

[0007] One objective of this invention is to solve the technical problems of incomplete separation of pulp and peel, excessive pulp residue, low yield, and low efficiency that exist in traditional methods such as manual digging, mechanical scraping, or water jetting.

[0008] To achieve the above objectives, the present invention provides a passion fruit pulp separation system, comprising: a feeding channel configured to allow passion fruits to maintain a predetermined posture under gravity and pass through sequentially one by one; a piercing and stirring unit disposed on the side of the feeding channel for piercing and stirring the passion fruits passing through the feeding channel; and a cutting unit disposed in the feeding channel downstream of the piercing and stirring unit; wherein the piercing and stirring unit comprises: a piercing rod with a piercing head at its front end; a stirring part sleeved on the piercing rod, the stirring part being configured to radially expand from a contracted state to an expanded structure under centrifugal force; a vibration mechanism drivenly connected to the piercing rod for driving the piercing rod to generate high-frequency micro-vibration; a rotation mechanism drivenly connected to the piercing rod for driving the piercing rod to rotate around its own axis; and a piercing motion mechanism fixedly connected to the vibration mechanism and the rotation mechanism for driving the piercing rod, the vibration mechanism, and the rotation mechanism as a whole to perform linear reciprocating motion relative to the feeding channel.

[0009] Preferably, the vibration mechanism is a piezoelectric ceramic actuator or a magnetostrictive actuator, generating a vibration frequency range of 200Hz to 500Hz and an amplitude range of 0.5mm to 2mm. Preferably, the stirring part is made of flexible food-grade silicone material, and its expansion structure includes a sleeve and multiple flexible ribs. Preferably, the puncture motion mechanism is a servo-electric slide module, capable of precisely controlling the puncture depth and movement speed of the puncture rod.

[0010] Compared to traditional methods such as manual digging, purely mechanical cutting and scraping, and water jetting, the passion fruit pulp separation system in this solution systematically solves the technical problems that have long existed and could not be fully resolved by these existing technologies.

[0011] First, compared to the inefficient and unstable manual digging, this solution solves the core problems of high dependence on skilled workers, low production efficiency, and inconsistent product quality. Manual digging relies on human skill and cannot quantify the force and angle of operation. Vigorous scraping in pursuit of higher yield can damage the mesocarp and seeds, introducing bitterness; gentle operation to avoid damage to the mesocarp and seeds results in a large amount of pulp remaining on the inner wall of the fruit shell, making it impossible to achieve both high yield and high quality. This invention, through the rotation and high-frequency vibration integrated with the piercing rod, achieves automated and standardized liquefaction of the pulp inside the fruit, allowing the pulp to flow out naturally by gravity, completely eliminating dependence on manual labor. While achieving large-scale production, it ensures that each fruit meets a relatively uniform separation standard. Second, purely mechanical cutting and scraping methods, whether using fixed scrapers or robotic spoons, apply force from the outside. To overcome the adhesion between the pulp and the peel, it inevitably involves squeezing, cutting, and shearing the pulp and seeds. This directly leads to two problems: first, the seed breakage rate remains high, severely affecting the flavor and stability of the juice; second, pulp residue is unavoidable because robotic arms or scrapers cannot perfectly conform to the unique contours of the inner wall of each fruit shell, especially the mesocarp (i.e., the white inner membrane), which is particularly prone to breakage and mixing with the pulp. This invention creatively solves the problem from within the fruit, using high-frequency micro-vibration (especially its cavitation effect) to break down the gel structure and weaken its adhesion to the peel (especially the white membrane of the mesocarp). The rotation of the flexible stirring section generates gentle turbulence, ultimately transforming the pulp into a homogeneous slurry. This inside-out liquefaction process achieves zero-contact, non-destructive processing of the seeds and allows the pulp to almost completely separate from the peel, while simultaneously achieving a low seed breakage rate and a high pulp yield—something that purely mechanical external forces cannot achieve. Finally, compared to water jet pulping technology, while water jetting avoids mechanical damage to some extent, it relies on high-pressure water flow, resulting in huge water consumption and organic wastewater rich in sugars and fruit acids, bringing a heavy environmental burden and subsequent treatment costs. More importantly, water flow inevitably dilutes the rich, original flavor and aroma of passion fruit, reducing the product's value. This invention eliminates the need for external water throughout the process, perfectly preserving the original concentration, typical flavor, and heat-sensitive nutrients of the passion fruit pulp. Furthermore, the piercing and stirring action, acting uniformly from the geometric center outwards, provides a more consistent and thorough treatment than water flow, which may leave some dead zones.

[0012] Furthermore, the puncture rod has an axial limiting section in the corresponding stirring section, which is close to one end of the puncture head. The stirring section includes: a first sleeve and a second sleeve, which are axially spaced and fitted onto the axial limiting section of the puncture rod, and are slidably engaged with the puncture rod through a keyway structure, allowing the sleeves to slide along the axial direction of the puncture rod and rotate synchronously with it; multiple flexible ribs are evenly distributed circumferentially and connected between the first sleeve and the second sleeve to form a cylindrical skeleton; and a return spring is fitted around the puncture rod and located at the first sleeve. Between the first and second sleeves, their two ends respectively abut against the opposing end faces of the two sleeves; when the piercing rod is stationary or rotating at low speed, the elastic force of the return spring drives the first and second sleeves away from each other, causing the flexible ribs to be in a contracted state and tightly attached to the outer periphery of the piercing rod; when the rotational speed of the piercing rod exceeds a predetermined threshold, the centrifugal force overcomes the elastic force of the return spring, driving the first and second sleeves to move closer to each other to compress the spring, causing the multiple flexible ribs to bulge outward in a radial direction and form an expansion structure for stirring.

[0013] Preferably, the keyway structure includes an axial groove disposed on the inner wall of the first sleeve and the second sleeve, and a radial protrusion disposed on the outer wall of the piercing rod, wherein the radial protrusion slides in engagement with the axial groove. Preferably, the flexible rib is made of food-grade silicone or rubber material, with a rectangular or elliptical cross-section and a thickness of 1-3 mm.

[0014] Preferably, the return spring is a compression helical spring, and its spring stiffness is configured such that when the rotation speed of the piercing rod reaches 300-500 rpm, the centrifugal force can just overcome the spring force to allow the stirring section to expand into an expanded structure state. Preferably, the opposing end faces of the first sleeve and the second sleeve are provided with spring positioning grooves for radial positioning of the return spring.

[0015] While a fixed, extended stirring head offers a simpler structure, the piercing action is not smooth enough. During piercing, the stirring section must maintain a minimum radial dimension to smoothly pass through the piercing hole and reduce the risk of tearing the fruit peel; conversely, during stirring, it needs to quickly transform into a large-area expansion structure to achieve efficient liquefaction. The core challenge is how to reliably and automatically switch between these two states within a simple structure. This solution utilizes the preload of the return spring to move the sleeve away, forcibly retracting the ribs to ensure a compact profile during piercing. Centrifugal force overcomes the spring force, driving the sleeve closer, and the ribs naturally expand into an umbrella shape. Without additional control signals or power sources, it achieves adaptive, passive switching of the stirring section's working state, resulting in a simple structure and reliable operation. Furthermore, a single actuator (piercing rod) can sequentially complete the two functionally contradictory actions of piercing and efficient stirring, simplifying the system structure and minimizing initial damage to the fruit peel.

[0016] Furthermore, the diameter of the axial limiting section is smaller than the diameter of the piercing rod. The diameter of this section matches the inner diameter of the first sleeve and the second sleeve, forming a transition fit or clearance fit. After the first sleeve and the second sleeve are fitted into the axial limiting section, their outer surfaces are flush with or slightly lower than the outer surfaces of the adjacent sections of the piercing rod, so that the stirring part forms an approximately smooth rod-shaped profile when it is in the contracted state. The piercing head is detachably connected to one end of the piercing rod through a threaded structure, and after being tightened, it forms an axial mechanical limit on the first sleeve and the second sleeve fitted into the axial limiting section, preventing them from moving axially or detaching from the piercing rod.

[0017] Preferably, the length of the axial limiting section is greater than the total length of the first sleeve, the second sleeve, and the return spring under maximum compression, providing sufficient travel space for the axial sliding of the sleeve. Preferably, the piercing head is conical or bullet-shaped with an internal or external thread at its large end that mates with the piercing rod. Preferably, it also includes an anti-loosening structure, which includes anti-loosening thread-locking adhesive applied to the threaded connection, or a spring washer and a locking nut, to prevent the piercing head from loosening under vibration.

[0018] This solution addresses the issues of precise positioning and stable guidance of the mixing unit components, as well as the streamlined design during the piercing process, reducing piercing resistance and fruit peel tearing damage. It also resolves the issues of disassembly and maintainability of key components, facilitating regular and thorough cleaning, disinfection, or replacement of damaged parts of the mixing unit, significantly improving the maintainability and hygiene of the equipment.

[0019] Furthermore, at least one round bead is fixedly disposed on the flexible rib of the stirring section; When the stirring part is an expanded structure including a central sleeve and multiple radial flexible ribs, the beads are disposed at the ends of the flexible ribs; when the stirring part is a structure including a first sleeve, a second sleeve and multiple flexible ribs, the beads are disposed in the middle of the flexible ribs.

[0020] The spherical beads in this design act as concentrated mass blocks, amplifying the centrifugal effect and generating stronger mechanical shearing and impact on the gel-like passion fruit pulp. This significantly reduces the time required to mix the pulp into a uniform paste. In particular, placing the beads in the center of the flexible ribs within the double-sleeve structure creates a uniform reinforcing ring within the pulp cavity, preventing ineffective mixing in the central area near the rod and resulting in more thorough and uniform pulp liquefaction. Furthermore, the additional centrifugal force provided by the beads helps the flexible ribs unfold more quickly and stably and maintain their umbrella-shaped working form, improving the dynamic stability of the mixing unit under high-speed rotation.

[0021] Furthermore, it also includes: a passion fruit positioning unit, disposed in the feeding channel and located above the piercing and stirring unit, for accurately positioning the passion fruit before the piercing operation; the passion fruit positioning unit includes: elastic guide components, symmetrically disposed on the inner walls of the left and right sides of the feeding channel, forming a V-shaped or arc-shaped positioning groove that gradually narrows from top to bottom between the elastic guide components on the left and right sides; a positioning stop block, disposed below the elastic guide components, controlled by a drive mechanism, capable of extending into the feeding channel to block the passion fruit that has been centered from continuing to fall, causing it to stop at the preset piercing position; and quickly retracting after the piercing and stirring operation is completed, releasing the passion fruit to continue falling.

[0022] Preferably, each elastic guide component includes: a smooth guide plate connected to the inner wall of the feeding channel via a hinge shaft, which can swing around the hinge point; a compression spring disposed between the inner wall of the feeding channel and the back of the smooth guide plate, providing elastic support force to the smooth guide plate toward the center of the channel; the elastic guide components on the left and right sides together form a positioning channel that gradually narrows from top to bottom, automatically guiding passion fruits of different diameters to the center through the symmetrical elastic restoring force of the spring.

[0023] Preferably, the hinge shaft is disposed at the upper end of the smooth guide plate, so that the guide plate can be swayed to accommodate passion fruit of different sizes.

[0024] Preferably, it also includes a position sensor for detecting whether the passion fruit has reached the puncture station and is connected to the control system signal of the positioning stop.

[0025] This solution addresses the issue of puncture positioning accuracy. Through symmetrical, elastic guiding components, passion fruit of various sizes can be automatically and precisely guided to the center of the channel, ensuring the puncture rod penetrates as close to the fruit's central axis as possible. This avoids uneven mixing, peel tearing, or seed damage caused by eccentric puncture. The elastic guiding structure is compatible with passion fruit of different sizes, enhancing the overall system's versatility.

[0026] Furthermore, multiple positioning blocks are evenly spaced on a loop transmission mechanism; adjacent positioning blocks form a support for a single passion fruit; the loop transmission mechanism is driven by a drive motor to perform intermittent cyclic motion; when an adjacent positioning block moves to the working section of the feeding channel, the positioning block extends into the feeding channel to block and support the passion fruit on it; after completing the piercing and stirring operation, the loop transmission mechanism advances one support distance, and the processed passion fruit falls from the support to the subsequent cutting unit, while bringing the next set of positioning blocks into the working section to receive new passion fruit.

[0027] Furthermore, the system also includes a control unit configured such that: when the passion fruit moves to the processing station, the piercing mechanism drives the piercing rod forward, causing it to pierce and penetrate the passion fruit; the rotating mechanism drives the piercing rod to rotate, and the stirring section expands under centrifugal force to form an expanded stirring head; simultaneously, the vibration mechanism drives the piercing rod to generate high-frequency micro-vibration. This solution coordinates the three actions of piercing, rotating, and vibrating through the control unit. The stirring section expands under centrifugal force to form an expanded structure, increasing the contact area and stirring area with the pulp; at the same time, the high-frequency micro-vibration disrupts the gel network structure of the pulp from the inside. This synergistic effect of mechanical shearing and cavitation enables the full liquefaction of the pulp and complete separation from the peel, thereby significantly improving the pulp yield and solving the problem that traditional manual digging or purely mechanical scraping cannot effectively overcome the adhesion between the pulp and the inner wall of the peel, resulting in serious pulp residue. Meanwhile, the flexible stirring section design also reduces the impact on the seeds. The control unit ensures that these actions are performed in synergy, thereby maximizing the protection of seed integrity while efficiently liquefying the pulp, ensuring the pure flavor of the final product.

[0028] Furthermore, the control unit is configured to: a) monitor the motor load current of the rotating mechanism in real time; when the load current is detected to enter a continuously decreasing channel from its peak, it determines that the pulp has entered the rapid liquefaction period, and dynamically adjust the rotation speed and vibration parameters based on the current decrease rate to optimize liquefaction efficiency; b) after the load current drops to a stable range, it synchronously monitors the fluctuation amplitude of the load current and the spectral characteristics of the vibration signal; when the following two conditions are met simultaneously and continue for a preset duration, it is determined that the pulp has been fully liquefied: the fluctuation amplitude of the load current is less than a first set threshold; the rate of change of the main frequency amplitude of the vibration signal is less than a second set threshold, and the low-frequency impact component is attenuated to the background noise level; c) once the liquefaction endpoint is reached, the corresponding mechanisms are shut down in the order of stopping the vibration mechanism first and then the rotating mechanism, the piercing rod is controlled to withdraw, and the loop transmission mechanism is started to step one station. This solution, through a phased, multi-signal fusion judgment strategy, avoids premature or delayed shutdown caused by short-term fluctuations in load current or vibration signal interference, greatly improving the accuracy of endpoint judgment. The control unit allows the system to actively adjust parameters during liquefaction to pursue efficiency, while switching to a conservative, stable confirmation mode near the endpoint, balancing efficiency and reliability. This configuration can adapt to passion fruit in different initial states (such as flesh content and ripeness) because it does not rely on a fixed absolute value of current, but rather on the relative trend and stability characteristics of the signal.

[0029] Furthermore, it also includes an intelligent freeze-drying unit that performs the following steps: S1. Pretreatment step: Add a compound freeze-drying protectant to the passion fruit pulp obtained by the passion fruit pulp separation system and mix evenly. The compound freeze-drying protectant includes the following components by mass percentage of the total pulp: 5%-8% maltodextrin, 1%-3% trehalose, and 1%-2% porous starch; S2. Loading and quick-freezing step: Spread the pretreated pulp evenly on a tray to a thickness of 5-10 mm and quick-freeze at -35℃ to -40℃ for 2-4 hours; S3. Intelligent freeze-drying step: Under vacuum, the process parameters of the freeze-drying process are dynamically controlled by an AI control system; wherein, the AI ​​control system performs the following operations: S31. Real-time acquisition of process parameters during the freeze-drying process, including material temperature, system vacuum degree, and cold trap temperature; S32. Input the process parameters into the pre-freezing system. The trained drying kinetics model is a machine learning model trained based on historical freeze-drying process data, material characteristic data, and final product quality data. S33: Based on the model's output, the temperature curve of the heating shelf and the vacuum control curve of the system are dynamically and collaboratively adjusted. Specifically, during the sublimation drying stage, the shelf temperature is controlled to approach the material collapse temperature safety threshold calculated in real-time by the model at the maximum allowable rate. This threshold is the collapse temperature of the dried material layer minus 3-5℃. During the analytical drying stage, based on the model's predicted rate of change in residual moisture, the shelf temperature is gradually increased to 40-50℃, while ensuring that the core temperature of the material remains below its glass transition temperature safety threshold. S4: Drying endpoint determination: When the residual moisture predicted by the model reaches a mass fraction of 3%-5%, the drying process is automatically terminated.

[0030] Preferably, the operation of dynamically adjusting the system vacuum degree includes: when the model predicts an increase in mass transfer resistance, controlling the system vacuum degree at 10-20 Pa; when the model predicts insufficient heat transfer, adjusting the system vacuum degree to 20-30 Pa. Preferably, the training data of the drying kinetic model includes the glass transition temperature, eutectic point temperature, sugar-acid composition, and solid content of the passion fruit pulp.

[0031] This solution effectively prevents structural collapse of high-sugar, high-acid slurries during freeze-drying through the synergistic effect of a composite freeze-drying protectant and AI dynamic control, thus maintaining the product's porous structure. Utilizing the adsorption properties of porous starch and an optimized freeze-drying curve, the loss of volatile flavor compounds and heat-sensitive nutrients is significantly reduced. The AI ​​system's coordinated regulation of heat and mass transfer processes improves drying efficiency, shortens the freeze-drying cycle, and reduces energy consumption. An intelligent control strategy based on real-time material status allows process parameters to adapt to the differences in characteristics between different batches of slurry, ensuring product quality stability.

[0032] The present invention provides a method for separating and freeze-drying passion fruit pulp using the aforementioned passion fruit pulp separation system, comprising the following steps: Step 1: Wash the passion fruit to remove surface impurities; then sort them. Step 2: Immerse the sorted passion fruit in a calcium chloride solution with a mass fraction of 1.0%-1.5% for 10-15 minutes under normal pressure; after removal, perform a coating treatment using a chitosan solution with a mass fraction of 1.0% and a mass fraction of 0.3%-0.5% glycerol to form a flexible protective film. Step 3: Feed the passion fruit processed in Step 2 into the passion fruit pulp separation system and perform the following sub-steps: The passion fruit is precisely centered and positioned at the piercing station by a positioning unit; the piercing rod is controlled to penetrate the passion fruit, and the rotation mechanism and high-frequency vibration mechanism are activated, working together for 60-120 seconds at a speed of 300-600 rpm and a vibration frequency of 200-500 Hz to fully liquefy the pulp; based on intelligent monitoring of load current and vibration signals, the degree of pulp liquefaction is judged, and processing is stopped sequentially after the threshold is reached; the passion fruit is then transported to the cutting unit for halving, allowing the liquefied pulp to flow out naturally; Step 4: Centrifuge the outflowing pulp to separate the whole seeds, pulp fibers and peel, and obtain passion fruit pulp. Step 5: Quick-freeze the passion fruit pulp at -35℃ to -40℃ for 2-4 hours, and then freeze-dry it for 20-30 hours under a vacuum of 10-30Pa and a desorption drying temperature of 40-50℃ to obtain whole passion fruit powder.

[0033] Preferably, the freeze-drying in step 5 adopts a segmented heating and desorption drying process: first, it is kept at -10℃ for 2 hours, then at 25℃ for 5 hours, and finally desorption drying is carried out at 45℃ to ensure that the product moisture content is less than 5% by mass.

[0034] This solution utilizes intelligently controlled puncture-stirring liquefaction technology to achieve complete separation of the pulp and peel while preserving the seeds and preventing bitterness. The entire low-temperature processing method maximizes the preservation of passion fruit's natural flavor, color, and heat-sensitive nutrients, resulting in a whole-fruit powder with excellent rehydration properties and natural flavor. An intelligent monitoring system based on multi-signal fusion ensures consistency and reliability throughout the processing, minimizing the impact of human factors on product quality. Through this complete processing flow, high-quality passion fruit powder, intact seeds, and pulp fiber are simultaneously obtained, achieving full utilization of passion fruit.

[0035] Furthermore, step 5 specifically includes the following sub-steps: Step 5.1, Pretreatment: Add a compound freeze-drying protectant to the passion fruit pulp obtained in step 4 and mix evenly. The compound freeze-drying protectant includes the following components in the total mass percentage of the pulp: 5%-8% maltodextrin, 1%-3% trehalose and 1%-2% porous starch. Step 5.2, loading and quick-freezing: Spread the pretreated slurry evenly on the tray to a thickness of 5-10 mm, and quick-freeze at -35℃ to -40℃ for 2-4 hours; Step 5.3, Intelligent Freeze-drying: Transfer the quick-frozen material to a vacuum freeze dryer, where the AI ​​control system performs the following operations: Real-time acquisition of process parameters including material temperature, system vacuum level, and cold trap temperature; The process parameters are input into a pre-trained drying kinetics model, which is trained based on historical freeze-drying data and material property data. Dynamically adjust the heating shelf temperature and system vacuum level based on model output: During the sublimation drying stage, the shelf temperature is controlled to approach the material collapse temperature safety threshold calculated in real time by the model at the maximum allowable rate. This threshold is the collapse temperature of the dried material layer minus 3-5℃. During the analytical drying stage, based on the model-predicted rate of change of residual moisture in the material, the shelf temperature is gradually increased to 40-50℃, while ensuring that the core temperature of the material is below the safe threshold of glass transition temperature. Step 5.4, Endpoint determination: When the model predicts that the residual moisture reaches 3%-5% by mass, the drying process will automatically terminate, and passion fruit powder will be obtained.

[0036] The present invention has at least the following beneficial effects: 1. This invention significantly improves pulp yield and separation thoroughness. It employs an inside-out processing method, using a piercing rod to carry the stirring unit into the fruit's interior. This is combined with the mechanical shearing force generated by the rotating mechanism and the high-frequency micro-vibration (especially its cavitation effect) generated by the vibrating mechanism. This combined technique allows for direct and uniform action on the pulp gel from within the fruit, effectively breaking down its three-dimensional network structure and weakening the adhesion between the pulp and the peel (especially the mesocarp), resulting in thorough pulp liquefaction. Compared to traditional external scraping methods that struggle to adhere to irregular inner walls, this internal liquefaction process ensures that the pulp almost completely detaches from the peel and flows out naturally under gravity, thus significantly reducing pulp residue and dramatically increasing pulp yield.

[0037] 2. This invention effectively maintains seed integrity and improves product quality. The mixing section is made of flexible material and expands during operation; the control unit ensures gentle mixing and vibration internally; and the pericarp is toughened during the pretreatment stage. The flexible, expandable mixing section, even at high speeds, exerts far less impact on the seeds than a rigid scraper or cutter. The internal, controlled liquefaction method avoids direct squeezing and cutting of the seeds. The pericarp toughening treatment reduces the risk of accidental pericarp breakage during puncture and mixing, leading to external mechanical damage to the seeds. These measures work together to achieve an extremely low seed breakage rate, avoiding bitterness introduced by broken seeds and ensuring the purity and stability of the flavor in the final product (such as juice or fruit powder).

[0038] 3. This invention fully preserves the original flavor and nutrients of passion fruit juice. The entire pulp separation process requires no introduction of external water (such as water jets). This avoids dilution of the passion fruit pulp with water, thus fully preserving its inherent rich aroma, typical flavor, and high-value soluble solids. Simultaneously, because the processing can be carried out at room temperature or low temperature and is completed quickly, damage to heat-sensitive nutrients (such as vitamin C) is reduced, maximizing the preservation of the product's natural characteristics and nutritional value.

[0039] 4. This invention achieves automated continuous production, improving efficiency and consistency. It incorporates a feeding channel, positioning unit, loop transmission mechanism, and a centralized control unit. The cooperation between the feeding channel and the positioning unit (such as elastic guide components and positioning blocks) enables automatic centering and precise positioning of the passion fruit, ensuring the accuracy of the puncture point. The loop transmission mechanism enables intermittent stepping at the workstation, streamlining the feeding, processing, and unloading process. The control unit coordinates the timing and parameters of actions such as puncture, rotation, vibration, and stepping. These mechanisms together constitute an automated system, overcoming the low efficiency and poor consistency of manual operation, achieving large-scale, standardized production, and reducing reliance on skilled workers.

[0040] 5. The control unit of this invention is configured to monitor the motor load current and vibration signal spectrum of the rotating mechanism in real time, and dynamically adjust parameters and determine the processing endpoint based on preset logic. By monitoring the changing trend of the load current, the system can sense different stages of pulp liquefaction (such as entering the rapid liquefaction period) and dynamically adjust the rotation speed and vibration parameters to optimize efficiency. By comprehensively analyzing the stability of current fluctuations and vibration characteristics (such as the rate of change of the main frequency amplitude and the attenuation of low-frequency impact components), the system can accurately determine whether the pulp has been fully liquefied, thereby stopping processing at the optimal time. This intelligent control strategy enables the system to adapt to fruits of different sizes and ripeness, ensuring processing effectiveness while avoiding energy waste and the negative impacts of over-processing, thus improving the overall system's intelligence level and the stability of processing quality.

[0041] 6. The intelligent freeze-drying unit integrated in this invention introduces an AI control system centered on a pre-trained drying kinetic model. It employs a machine learning model (drying kinetic model) trained based on historical freeze-drying process data, material characteristic data, and final product quality data. The model receives real-time input of process parameters such as material temperature, system vacuum, and cold trap temperature, enabling dynamic monitoring of the material's real-time collapse temperature, residual moisture, and mass transfer resistance. This fundamentally avoids the product quality instability caused by the inability to adapt to fluctuations in material characteristics due to the reliance on fixed procedures in traditional methods. During the sublimation drying stage, based on the material collapse temperature safety threshold calculated in real-time by the model, the heating shelf temperature curve and system vacuum control curve are dynamically and collaboratively controlled, ensuring the shelf temperature approaches this safety threshold at the maximum permissible rate. Compared to the conservative, fixed heating curves used in traditional processes, this invention can sublimate at the fastest safe rate under the current conditions while ensuring the product does not collapse, thus significantly shortening the sublimation drying time and reducing process energy consumption. Simultaneously, the collaborative control of vacuum effectively optimizes the matching relationship between heat and mass transfer, further improving drying efficiency. During the desorption drying stage, the shelf temperature is gradually increased based on the model-predicted rate of change of residual moisture in the material, while ensuring that the core temperature of the material is below its glass transition temperature safety threshold. This effectively preserves heat-sensitive substances (such as vitamin C and aromatic substances) in the passion fruit pulp and ensures that the final product has excellent rehydration properties and original natural flavor.

[0042] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the passion fruit pulp separation system of the present invention; Figure 2 This is a schematic diagram of the overall structure of the puncture and stirring unit of the present invention; Figure 3 This is a schematic diagram showing the disassembled structure of the puncture and stirring unit of the present invention; Figure 4 This is a schematic diagram of the loop transmission mechanism of the present invention; Figure 5 This is a schematic diagram of the stirring part of the present invention; the left side of the figure shows a contracted state, and the right side shows an expanded state. Figure 6 This is a flowchart of a method for separating and freeze-drying passion fruit pulp and peel according to the present invention. Figure 7 A schematic diagram of the anatomical structure of passion fruit; Figure 8This is a picture of the passion fruit pulp after separation according to the present invention.

[0044] In the diagram: 1. Hopper; 2. Feeding channel; 3. Piercing and stirring unit; 4. Cutting unit; 5. Passion fruit; 6. Positioning block; 7. Elastic guide component; 31. Piercing rod; 32. Stirring part; 33. Piercing head; 34. Vibration mechanism; 35. Rotation mechanism; 36. Piercing motion mechanism; 37. Axial limiting section; 38. Return spring; 39. Keyway structure; 321. Central sleeve; 322. Flexible rib; 323. Ball; 324. First sleeve; 325. Second sleeve; 61. Circular transmission mechanism; 62. Locking position. Detailed Implementation

[0045] The present invention will now be described in further detail with reference to examples, so that those skilled in the art can implement it based on the description.

[0046] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not exclude the presence or addition of one or more other elements or combinations thereof.

[0047] For ease of understanding and implementation, such as Figures 1-8 As shown, the passion fruit pulp separation system of the present invention includes a feeding channel 2 made of stainless steel, the inner wall of which can be polished. The inclination angle of the feeding channel is preferably set between 15 and 60 degrees, and the width is 40 to 60 millimeters, allowing the passion fruit 5 to pass through individually with the stem facing forward under gravity. Guide ribs can be installed inside the channel, with a height of 3 to 5 millimeters and a spacing of 20 to 30 millimeters, to ensure the fruit maintains a stable posture during descent. The upper end of the feeding channel 2 can be connected to the hopper 1, and the lower end leads to the cutting unit 4. The entire channel is fixed to the equipment frame by a bracket.

[0048] The piercing and stirring unit 3 is installed on the side of the feeding channel 2, with its centerline 80 to 120 mm from the bottom of the channel. The piercing rod 31 can be made of stainless steel with a diameter of 5 to 8 mm, and the piercing head 33 installed at the front end can be a conical design with a cone angle of 30 to 45 degrees. The stirring part 32 can be sleeved on the piercing rod 31 and is made of food-grade silicone or thermoplastic polyurethane. The vibration mechanism 34 can be a piezoelectric ceramic vibrator with a frequency range of 200 to 500 Hz and an amplitude range of 0.5 to 2 mm. The vibration output part of the vibration mechanism is fixed to the rear end of the piercing rod 31 by means of sleeve or threaded connection, which can drive the piercing rod to vibrate at high frequency. The rotating mechanism 35 can be a servo motor. The rotating output shaft of the rotating mechanism 35 is provided with a mounting recess. The vibration mechanism is installed in the mounting recess. The rotating mechanism drives the vibration mechanism and the piercing rod to rotate together, and the speed can be adjusted within the range of 0 to 1000 revolutions per minute. The puncture motion mechanism 36 can be an electric slide with a stroke of 50 to 200 mm and a moving speed of 10 to 50 mm per second. The rotating mechanism 35 is fixed by a mounting plate, which drives the rotating mechanism (along with the vibration mechanism and the puncture rod) to reciprocate linearly to perform the puncture action.

[0049] The cutting unit 4 is located in the feeding channel 2, 150 to 200 mm downstream of the piercing and mixing unit 3. It may contain a high-speed rotating disc blade, which may be made of food-grade stainless steel with a thickness of 1 to 2 mm and a rotation speed of 200 to 500 revolutions per minute. The mounting bracket of the cutting unit 4 may have elongated holes to facilitate adjustment of its specific position in the feeding channel 2 according to actual needs.

[0050] During operation, passion fruit 5 in hopper 1 first enters feeding channel 2 and slides downwards under gravity. When the fruit reaches the piercing station, the piercing mechanism 36 pushes the piercing rod 31 forward, causing it to pierce the passion fruit until the stirring section is inside. Subsequently, the rotating mechanism 35 drives the piercing rod 31 to rotate, and the stirring section 32 unfolds under centrifugal force, while the vibration mechanism 34 starts working. Under the combined action of rotation and vibration, the pulp is broken and liquefied. After processing, the piercing rod 31 retracts, and the passion fruit continues to fall to the cutting unit 4 where it is cut in half, and the liquefied pulp flows out automatically.

[0051] This method effectively separates the pulp from the peel while preserving the integrity of the seeds. Mechanized processing improves production efficiency and maintains good consistency.

[0052] One embodiment of the stirring section is as follows: Figure 5As shown, the stirring section 32 is located in the axial limiting section 37 of the piercing rod 31. This section can be machined into a cylindrical surface with a diameter of 4 to 6 mm and a length of 80 to 120 mm. The first sleeve 324 and the second sleeve 325 can be made of stainless steel or engineering plastic, and their inner diameters form a clearance fit with the axial limiting section 37, with the clearance controlled at 0.1 to 0.3 mm. The outer diameter of the sleeves can be designed to be 6 to 8 mm, and the length of a single sleeve is 15 to 25 mm. The distance between the two sleeves can be maintained at 20 to 50 mm in the initial state, and they are connected to the piercing rod 31 through a keyway structure 39. The keyway width can be 3 to 5 mm, and the depth can be 1 to 2 mm.

[0053] Multiple flexible ribs 322 can be made of food-grade silicone material, with 6 to 8 ribs evenly arranged circumferentially. Each rib has a rectangular cross-section, a thickness of 1.5 to 2.5 mm, and a width of 3 to 5 mm. The two ends of the ribs are fixedly connected to the first sleeve 324 and the second sleeve 325 by bonding or molding, forming a cylindrical skeleton structure. The return spring 38 can be a stainless steel compression spring, sleeved around the piercing rod 31. The spring has an outer diameter of 8 to 12 mm, a wire diameter of 0.8 to 1.2 mm, and a free length of 40 to 60 mm. The two ends of the spring abut against the opposing end faces of the two sleeves, and the end faces can be machined with spring positioning grooves with a depth of 1 to 2 mm.

[0054] When the piercing rod 31 is stationary or rotating at low speed, the elastic force of the return spring 38 keeps the two sleeves at their maximum distance. At this time, the flexible rib 322 is in a contracted state, closely attached to the outer surface of the piercing rod 31, with an overall outer diameter not exceeding 8 mm. When the rotation speed reaches 300 to 500 revolutions per minute, the centrifugal force overcomes the spring force, causing the two sleeves to approach each other to a distance of 15 to 25 mm. The flexible rib 322 bulges outward radially, forming an expansion structure with a maximum outer diameter of 10 to 50 mm (the actual setting is based on the average diameter of each batch of sorted fruit; preferably, the flexible rib should be kept away from the inner wall of the passion fruit cavity as much as possible). The stiffness coefficient of the return spring 38 can be selected in the range of 0.5 to 2 N / mm to ensure reliable expansion at the set rotation speed.

[0055] This implementation achieves automatic expansion and contraction of the mixing section through a purely mechanical structure. It maintains a small profile during piercing to reduce resistance and forms a large mixing area during operation to improve efficiency. The structure is simple and reliable, requires no additional control mechanisms, and is easy to disassemble and clean.

[0056] In another embodiment, the axial limiting section 37 can be machined into a cylindrical surface with a diameter of 4 to 5 mm, which is 1 to 2 mm smaller than the diameter of the rest of the piercing rod 31. The length of this section can be set to 100 to 150 mm. The inner diameters of the first sleeve 324 and the second sleeve 325 can form a transition fit with the axial limiting section 37. The outer diameter of the sleeve can be machined to 6 to 7 mm so that it is substantially flush with the outer surface of the adjacent section of the piercing rod 31 in the retracted state, with the height difference controlled within 0.1 to 0.3 mm.

[0057] The piercing head 33 can be made of 304 stainless steel and is connected to one end of the piercing rod 31 via a fine thread of M5 to M8. The thread length can be designed to be 8 to 12 mm. The tip of the piercing head 33 can be machined into a conical shape with a cone angle of 30 to 40 degrees and a tip fillet radius of 0.2 to 0.5 mm. When the piercing head 33 is tightened, its root end face can make close contact with the end face of the second sleeve 325, forming an axial mechanical limit.

[0058] The anti-loosening structure can be achieved by applying Loctite 243 threadlocker to the threaded connection, or by adding a spring washer or lock nut to the threaded connection. Standard spring washers can be selected, with specifications matching the thread size. Lock nuts can be nylon inserts with a thickness of 3 to 5 mm. The length of the axial limiting section 37 must ensure that, even with the first sleeve 324, the second sleeve 325, and the return spring 38 under maximum compression, there is still a 2 to 5 mm movement allowance between the two sleeves.

[0059] This implementation ensures the stability of the stirring unit 32 under high-speed rotation and vibration conditions through precise dimensional fit and reliable connection structure. The detachable connection facilitates regular cleaning and maintenance, while the anti-loosening structure guarantees the long-term reliability of the equipment. The assembly sequence of the entire assembly can be as follows: first, place the return spring 38 on the axial limiting section 37; then, sequentially install the first sleeve 324 and the second sleeve 325; finally, tighten the piercing head 33 and apply anti-loosening measures.

[0060] In another embodiment, one or more beads 323 may be fixedly mounted on the flexible rib 322. The number of beads can be selected from 1 to 3 depending on the length of the rib. The beads 323 can be food-grade ceramic beads with a diameter of 3 to 5 mm. The installation position varies depending on the structure of the stirring part. The beads 323 can be located in the middle of the flexible rib 322, 15 to 25 mm away from both ends.

[0061] The beads 323 can be fixedly connected to the flexible ribs 322 via a coating molding process, with the coating layer thickness controlled between 0.5 and 1 mm. The coating material can be the same food-grade silicone as the ribs, with a hardness between Shore A 40 and 60. The embedment depth of the beads 323 into the ribs can be designed to be 1 / 3 to 1 / 2 of the ball diameter to ensure a firm connection. The total weight of the beads 323 in each stirring section 32 can be controlled within the range of 5 to 15 grams to provide appropriate centrifugal mass.

[0062] During the expansion structure's deployment, the beads 323 move in a circular motion along with the flexible ribs 322. At a rotational speed of 300 to 500 revolutions per minute, a single bead 323 can generate a centrifugal force of 2 to 8 Newtons. These beads 323 enhance the impact and shearing action on the fruit pulp gel during their movement, while also helping to maintain the stability of the expansion structure. The surface of the beads 323 can be processed into a smooth spherical shape to avoid damaging the seeds during stirring.

[0063] This implementation method enhances the centrifugal effect and impact during the mixing process by adding an appropriate mass of beads 323. The proper arrangement of the beads 323 improves the efficiency and uniformity of pulp crushing without significantly increasing resistance. The rubber-coated fixing method ensures reliable connection and meets the hygiene requirements of food processing equipment.

[0064] In another embodiment, the passion fruit positioning unit is installed in the feeding channel 2 50 to 300 mm above the piercing and stirring unit 3 (the actual position depends on the size of the fruit). Elastic guide components 7 are symmetrically arranged on the left and right inner walls of the feeding channel 2. Each guide component may include a smooth guide plate and a compression spring. The smooth guide plate may be made of stainless steel with a thickness of 2 to 3 mm, covered with a food-grade polyurethane layer with a thickness of 1 to 1.5 mm. The guide plate is 50 to 80 mm wide and 120 to 180 mm high, and is connected to the inner wall of the channel via a hinge shaft installed 30 to 50 mm below the upper end of the guide plate.

[0065] The compression spring can be made of stainless steel and is installed between the inner wall of the channel and the back of the smooth guide plate. The spring wire diameter is 1 to 1.5 mm, the outer diameter is 12 to 16 mm, and the free length is 60 to 80 mm. The positioning channels formed by the elastic guide components 7 on both sides have an upper opening width of 80 to 100 mm, a lower opening width of 40 to 60 mm, and a channel depth of 150 to 200 mm. The preload of the spring can be adjusted within the range of 2 to 10 Newtons to ensure that appropriate clamping force is provided for passion fruits of different sizes.

[0066] The positioning stop 6 is positioned 50 to 80 mm below the elastic guide component 7. The head of the stop can be designed in an arc shape with a radius of 30 to 40 mm, and its surface is covered with a 3 to 5 mm thick food-grade silicone layer. The drive unit of the drive mechanism is connected to the positioning stop. The drive mechanism can be a solenoid-controlled cylinder with a response time of less than 0.1 seconds and a thrust of 80 to 120 Newtons. The depth to which the stop extends into the feeding channel 2 can be adjusted within the range of 20 to 30 mm.

[0067] The position sensor can be a diffuse reflection type photoelectric sensor, installed 20 to 30 mm above the stop, with an adjustable detection distance of 10 to 50 mm. The sensor is connected to the control system via a cable, and senses the position when the passion fruit reaches the predetermined location. The entire positioning unit is fixed to the side wall of the feeding channel 2 by a bracket, which can be equipped with elongated holes to adjust the installation height.

[0068] During operation, the passion fruit 5 first enters the positioning channel formed by the elastic guide component 7, and automatically centers itself under the action of the compression spring. When the fruit falls to the stop position, the position sensor detects a signal, and the stop remains extended to support the fruit. After piercing and stirring is completed, the stop quickly retracts, and the fruit continues to fall. This positioning method ensures the accuracy of the piercing position and adapts to passion fruit of different sizes.

[0069] In another embodiment, the driving mechanism for the positioning blocks is driven by a loop transmission mechanism instead of a cylinder. There can be 3 to 9 positioning blocks 6, evenly spaced and fixed to the loop transmission mechanism 61. The center distance between adjacent positioning blocks 6 can be set to 60 to 120 mm (depending on the actual fruit diameter), and the effective accommodating space of each slot 62 has a width of 60 to 80 mm and a depth of 40 to 60 mm. The positioning blocks 6 can be made of food-grade nylon, with a height of 30 to 50 mm and a thickness of 8 to 12 mm. The supporting surface of the blocks can preferably be machined into an arc-shaped groove with a radius of 25 to 35 mm and a depth of 5 to 8 mm, and the surface can be covered with a 2 to 3 mm thick silicone layer to increase friction.

[0070] The loop drive mechanism 61 can be either a synchronous belt drive or a chain drive. The synchronous belt can be made of polyurethane, with a width of 30 to 50 mm and a thickness of 5 to 8 mm. The chain drive can be a stainless steel roller chain with a pitch of 12.7 to 25.4 mm. The drive mechanism is driven by a servo motor with a power range of 200 to 400 watts, equipped with a reducer with a reduction ratio of 20:1 to 50:1. A flow guide trough can be installed below the mechanism, with a width of 150 to 200 mm, a depth of 80 to 120 mm, and an inclination angle of 10 to 15 degrees, to guide the processed passion fruit towards the cutting unit.

[0071] During operation, the cyclic transmission mechanism 61 performs intermittent cyclic motion, advancing one positioning distance in each cycle, with a dwell time that can be set to 1 to 10 seconds. When the positioning block 6 moves to the working section of the feeding channel 2, the passion fruit 5 falls into the positioning position 62 and is supported by the positioning block 6. After the piercing and stirring operation is completed, the transmission mechanism advances one positioning position, and the processed passion fruit rotates out of the working section with the positioning block, falling into the guide trough due to the loss of support.

[0072] Position detection can be achieved using proximity switches or photoelectric sensors, installed at key locations in the transmission mechanism to detect whether the stop is accurately in place. The sensor detection distance can be adjusted within the range of 5 to 10 millimeters, and the signal is processed by a PLC to form a closed-loop control with the drive motor. The entire loop transmission mechanism 61 is mounted on the equipment frame via a bracket, which can be equipped with adjustment slots to facilitate adjustment of the transmission belt tension.

[0073] In another implementation, the control unit can be a programmable logic controller (PLC) equipped with digital input / output (DIO) modules and analog input modules. The input voltage can be 220V AC, and the output voltage includes 24V DC and 0-10V analog outputs. The control unit connects to a host computer via an Ethernet or RS485 communication interface, and the sampling period can be set to 1-10 milliseconds. The program memory capacity can be selected from 16 to 32 megabytes, and the data memory capacity from 8 to 16 megabytes, supporting ladder logic and structured text programming languages.

[0074] When the passion fruit 5 moves to the processing station, the control unit first receives a signal from the position sensor and, after a delay of 0.1 to 0.3 seconds, activates the piercing mechanism 36. The advancing speed of the piercing mechanism 36 can be controlled in segments. In the initial stage, a slower speed of 10 to 20 mm per second is used, and when it is 5 to 10 mm away from the surface of the passion fruit, it switches to a normal speed of 30 to 50 mm per second. The piercing depth is controlled by a limit switch or an encoder. After the piercing rod 31 penetrates the fruit, it continues to advance 2 to 20 mm to ensure complete penetration.

[0075] After the puncture rod 31 reaches the target position, the control unit simultaneously activates the rotation mechanism 35 and the vibration mechanism 34. The acceleration time of the rotation mechanism 35 can be set to 0.5 to 1 second, and the target rotation speed is adjusted between 300 and 600 revolutions per minute depending on the size of the passion fruit. The activation delay of the vibration mechanism 34 can be set to 0.05 to 0.1 seconds, the vibration frequency is adjustable in the range of 200 to 500 Hz, and the amplitude can be varied between 0.5 and 2 mm via voltage control. The activation time difference between the two mechanisms is controlled within 0.2 seconds to ensure synergistic effect.

[0076] The control unit monitors the operating status of each mechanism in real time via analog input modules, including motor current, speed feedback, and vibration frequency. Operating parameters can be set and displayed through a human-machine interface (HMI), which can include parameter setting screens, operating status screens, and alarm record screens. Emergency stop and reset buttons are prominently located on the control panel, with an emergency stop response time of less than 50 milliseconds. The control system is also equipped with overload protection and fault diagnosis functions; when an abnormality is detected, the relevant mechanism is immediately stopped and an alarm signal is issued.

[0077] In another embodiment, the control unit monitors the load current in real time via a current sensor mounted on the power supply line of the rotating mechanism 35 motor. The current sensor's range can be selected from 0 to 10 amperes. The sampling frequency can be set to 1 kHz, and the collected current signal is filtered before being sent to the control unit. When the load current is detected to have decreased by more than 15% to 25% from its initial peak and maintained a stable downward trend for more than 2 to 3 seconds, it is determined that the pulp has entered the rapid liquefaction period. At this time, the control unit increases the rotation speed by 10 to 30 revolutions per second according to the rate of current decrease, while simultaneously increasing the vibration frequency by 10 to 20 Hz.

[0078] Once the load current drops to a stable range, the control unit synchronously monitors the current fluctuation amplitude and vibration spectrum characteristics. The first threshold for the current fluctuation amplitude can be set to 0.3 to 0.5 amperes, obtained by calculating the standard deviation of 20 to 30 consecutive sampling points. The vibration signal is acquired by an accelerometer mounted on the base of the puncture rod 31; the sensor range can be ±50g, and the frequency range is 0.5 to 5 kHz. The second threshold for the rate of change of the dominant frequency amplitude of the vibration signal can be set to 2% to 3%, obtained by analyzing the signal within a 125 to 250 millisecond time window using Fast Fourier Transform. The background noise level of the low-frequency impact component can be benchmarked as 5% to 8% of the total vibration energy.

[0079] The preset duration can be set to 1.0 to 1.5 seconds, during which the above two conditions must be continuously met. The control unit executes a judgment logic every 100 milliseconds. When the standard is met for 10 to 15 consecutive judgment cycles, the pulp liquefaction is confirmed to be complete. After reaching the liquefaction endpoint, the control unit first stops the vibration mechanism 34, then stops the rotation mechanism 35 after a delay of 0.2 to 0.3 seconds, and then controls the piercing rod 31 to retract after a stabilization time of 0.5 to 0.8 seconds. The speed of the entire retraction process can be controlled at 20 to 30 millimeters per second. After retraction is completed, a signal is immediately sent to start the loop transmission mechanism 61 to advance one step.

[0080] This implementation method, through multi-signal fusion analysis and a phased control strategy, can accurately determine the pulp liquefaction state and avoid stopping processing too early or too late. Adaptive parameter adjustment ensures that passion fruit of different sizes and ripeness receive appropriate processing intensity, improving product quality consistency.

[0081] In another embodiment, the intelligent freeze-drying unit can be an industrial vacuum freeze dryer, with a freeze-drying area selectable between 5 and 50 square meters, equipped with a programmable heated shelf system. The maltodextrin in the composite freeze-drying protectant can be a type with a DE value of 15-20, preferably added at 6% of the total slurry mass; trehalose can be a food-grade crystalline product, preferably added at 2%; and porous starch can be a modified product derived from corn, with a pore size range of 0.1-1 micrometers and a specific surface area of ​​200-400 square meters / gram, preferably added at 1.5%. These raw materials can be purchased from food additive suppliers. Before use, they should be dry-mixed evenly and then slowly added to the slurry while stirring for 10-15 minutes. The loading step can use an automatic spreader to evenly spread the slurry onto an aluminum alloy tray, preferably with a spreading thickness of 8 millimeters. The quick-freezing process can be carried out in a quick-freezing chamber, preferably at -38°C, for a time of 3 hours.

[0082] The AI ​​control system employs a drying kinetic model based on a long short-term memory neural network architecture. This network architecture consists of one input layer, three hidden layers, and one output layer. The input layer has eight nodes, corresponding to eight input parameters: material temperature, shelf temperature, system vacuum, cold trap temperature, drying time, slurry sugar content, slurry acidity, and solids content. The three hidden layers have 64, 32, and 16 nodes, respectively, using the ReLU activation function. The output layer has three nodes, outputting the predicted material collapse temperature, the predicted residual moisture content, and the mass transfer resistance coefficient. The network weights are initialized using the Xavier method, and the loss function is a combination of mean squared error and absolute error.

[0083] The training data for the drying kinetics model came from a historical freeze-drying process database, containing complete freeze-drying process records for at least 800 batches. Each batch of data included a sequence of process parameters collected at 5-minute intervals, along with corresponding material property data. Material property data were determined experimentally: glass transition temperature was determined using differential scanning calorimetry, eutectic point temperature using resistance method, sugar-acid composition using high-performance liquid chromatography, and solids content using a refractometer. Before training, the data was standardized, normalizing each parameter to the 0-1 range. Training used the Adam optimizer with an initial learning rate of 0.001, a batch size of 32, and 200 training epochs.

[0084] During the freeze-drying process, the AI ​​control system receives real-time data input every 5 minutes and calculates three output parameters through the model. Based on the predicted material collapse temperature, the system dynamically sets the upper limit of the shelf temperature, which is set as the predicted value minus a safety margin of 4°C. When the mass transfer resistance coefficient output value exceeds the set threshold of 0.85, the control system adjusts the vacuum degree to the range of 10-15 Pa; when the mass transfer resistance coefficient is lower than 0.7, the vacuum degree is adjusted to the range of 25-30 Pa. The predicted residual moisture value is used to determine the drying endpoint; when three consecutive predicted values ​​are all below 4%, the system determines that drying is complete. The entire freeze-drying cycle can be controlled within 20-24 hours. The model is incrementally trained every six months using newly added production data to update the network weights and maintain prediction accuracy.

[0085] This implementation method achieves intelligent control of the freeze-drying process by establishing a precise drying kinetic model. The combined use of composite preservatives enhances the stability of the slurry system, and dynamic adjustment of process parameters can adapt to the differences in raw material characteristics between different batches. The entire system can be connected to the upstream pulp separation unit via a conveyor belt to achieve continuous production.

[0086] This invention provides a method for separating and freeze-drying passion fruit pulp, comprising the following steps: In step 1, passion fruit washing can be done using a drum washing machine, with the washing water temperature controlled between 15 and 25 degrees Celsius, and the washing time between 3 and 5 minutes. The sorting process can be done manually or mechanically, but is more preferably achieved through a machine vision system. The camera resolution can be selected from 2 to 5 megapixels, and the fruit is sorted into three grades based on diameter: 40 to 50 mm, 50 to 60 mm, and 60 to 70 mm. The sorting speed can reach 60 to 90 fruits per minute, and defective fruits are automatically removed by a pneumatic pusher.

[0087] Step 2, the peel toughening treatment, can be performed using a 1.0% to 1.5% (w / w) food-grade calcium chloride solution, with the soaking temperature maintained at 20 to 30 degrees Celsius and the soaking time at 10 to 15 minutes. The coating treatment can be done by spraying or dipping, with the chitosan solution concentration controlled at 0.8% to 1.2% (w / w) and the glycerol addition at 0.3% to 0.5% (w / w). The treated passion fruit is then air-dried at 35 to 45 degrees Celsius for 5 to 10 minutes to form a complete protective film.

[0088] Step 3 involves processing the passion fruit pulp using the aforementioned system. The piercing speed of the piercing rod 31 can be controlled between 20 and 40 millimeters per second, the rotation speed of the rotating mechanism 35 is set between 400 and 500 revolutions per minute, and the frequency of the vibration mechanism 34 is adjusted between 300 and 400 Hz. The processing time is adjusted between 70 and 100 seconds depending on the size of the fruit. The processing endpoint is determined by monitoring the motor load current and vibration signal. The current fluctuation threshold is set between 0.3 and 0.5 amperes, and the vibration signal change rate threshold is set between 2% and 3%.

[0089] Step 4, solid-liquid separation, can be performed using a horizontal spiral sedimentation centrifuge with a drum speed of 1500 to 2500 rpm and a differential speed of 10 to 20 rpm. The separated seeds are then further cleaned using a vibrating screen with a mesh size of 2 to 3 mm. The pulp fibers can be separated through an 80 to 100 mesh screen, resulting in a pulp with a soluble solids content of 12% to 16%.

[0090] Step 5, freeze-drying, involves first rapid freezing at -38 to -40 degrees Celsius for 2.5 to 3.5 hours, followed by desorption drying under a vacuum of 10 to 20 Pa. The drying process employs segmented heating: first maintaining the temperature at -10 degrees Celsius for 2 hours, then at 25 degrees Celsius for 5 hours, and finally drying at 45 degrees Celsius, for a total drying time of 22 to 26 hours. The finished product's moisture content is controlled between 3% and 5% by mass, and it is packaged in nitrogen-filled aluminum foil bags.

[0091] Example 1: Experimental application of the freeze-drying method for separating passion fruit pulp and peel This embodiment selected a batch of freshly picked Tainong No. 1 passion fruit, with uniform fruit maturity (sampling test showed soluble solids content of 13%-15%), fruit diameter ranging from 50-60 mm (medium size), totaling 100 kg. The experimental environment temperature was controlled at 20-25℃, and the relative humidity at 50%-60%.

[0092] The experimental equipment and materials include: cleaning equipment: drum washing machine; treatment solutions: food-grade calcium chloride (purity ≥96%), chitosan (degree of deacetylation ≥90%), glycerol (food grade); the passion fruit pulp separation system of this invention; centrifugation equipment: horizontal spiral sedimentation centrifuge; freeze-drying equipment: vacuum freeze dryer; testing instruments: digital refractometer (for measuring soluble solids), moisture analyzer, vibration spectrum analyzer; HPLC system (for analyzing nutritional components).

[0093] Implementation process Step 1: Cleaning and Sorting The passion fruit was poured into a drum-type washing machine, and cleaning water (set to 20℃) was added. The washing time was 4 minutes. The drum rotated at 10 rpm, removing surface impurities and dirt through friction and water flow. After washing, the fruit surface was smooth and free of visible contaminants. The washed passion fruit was then sorted. A total of 80 kg of qualified fruit with a diameter of 50-60 mm was sorted out for subsequent processing.

[0094] Step 2: Peel toughening and coating treatment Prepare a 1.2% (w / w) calcium chloride solution (temperature controlled at 25℃). Completely immerse the sorted passion fruit in the solution for 12 minutes. Stir gently during immersion to ensure even contact. After removal, the fruit peel will be more resilient and less prone to cracking. Prepare a coating solution containing 1.0% (w / w) chitosan and 0.4% (w / w) glycerol (solvent: deionized water). Immerse the passion fruit in the coating solution for 30 seconds, then drain excess liquid. Subsequently, place the fruit in a hot air drying oven at 40℃ for 8 minutes to form a uniform, flexible protective film. After treatment, a transparent film forms on the fruit surface, with a slightly sticky feel.

[0095] Step 3: Pulp separation system processing The coated passion fruit is fed into the pulp separation system. The feeding channel is tilted at 30° and 50 mm wide. The parameters of the piercing and stirring unit are set via the control unit: piercing rod insertion speed 30 mm / s, rotation speed 450 rpm, vibration frequency 350 Hz, and processing time 80 seconds. The positioning unit ensures precise centering of the passion fruit.

[0096] Operation process: Passion fruit enters the feeding channel, automatically centers itself through the elastic guide component, and is blocked at the piercing station by the positioning stop (driven by the loop transmission mechanism). After the control unit detects that the fruit is in place, it starts the piercing motion mechanism, and the piercing rod pierces and penetrates the passion fruit (piercing depth of about 70 mm to ensure complete penetration). At the same time, the rotation mechanism and vibration mechanism are started, and the stirring part expands into an expanded structure (maximum outer diameter of about 40 mm) under centrifugal force, working in conjunction with high-frequency micro-vibration.

[0097] The control unit monitors the load current and vibration signal of the rotating mechanism motor in real time: the initial load current is 4.5 A, and after entering the rapid liquefaction period, the current drops to 3.0 A (the rate of decrease is about 0.5 A / s). The system dynamically increases the rotation speed to 480 rpm and the vibration frequency to 370 Hz. When the load current stabilizes between 2.8-3.0 A (fluctuation amplitude <0.4 A), and the rate of change of the main frequency amplitude of the vibration signal is <2.5%, and the low-frequency impact component decays to the background noise level (<5% of the total energy), it is determined that the pulp has been fully liquefied (lasting 1.2 seconds). The control unit stops the vibration mechanism sequentially (stops the rotating mechanism after a delay of 0.25 seconds), the piercing rod retracts (speed 25 mm / s), the loop transmission mechanism steps forward one station, and the processed passion fruit falls to the cutting unit.

[0098] The cutting unit cuts the passion fruit in half (disc blade speed 400 rpm), and the liquefied pulp flows out naturally and is collected in a sterile container.

[0099] Statistical results: The pulp flowed smoothly, with very little pulp remaining on the inner wall of the fruit shell, and the seed integrity rate was ≥98% (only 2 slightly damaged seeds were found in a random sample of 100 seeds). Yield calculation: 80 kg of fresh fruit produced 52 kg of pulp, with a yield of approximately 65%.

[0100] Step 4: Centrifugation The collected fruit pulp was fed into a horizontal spiral sedimentation centrifuge, with the drum speed set at 2000 rpm, the differential speed at 15 rpm, and the processing time at 10 minutes. After separation, three layers of product were obtained: Top layer: passion fruit pulp (soluble solids content 14%), weighing 45 kg; Middle layer: pulp fibers (separated through a 100-mesh sieve), weighing 5 kg; Bottom layer: whole seeds (cleaned through a vibrating screen with a 2.5 mm mesh), weighing 2 kg. The pulp was orange-yellow in color, homogeneous in texture, and free of visible fibers or seed fragments.

[0101] Step 5: Freeze-drying Spread passion fruit pulp evenly on the shelf of a freeze dryer (about 10 mm thick) and quick-freeze at -38°C for 3 hours until the pulp is completely solidified.

[0102] The vacuum system was activated, and the vacuum level was controlled at 20 Pa. A segmented heating process was adopted: First stage: -10℃ for 2 hours for initial sublimation. Second stage: 25℃ for 5 hours to accelerate moisture desorption. Third stage: Desorption drying at 45℃ for 20 hours. The total drying time was 27 hours, during which the material temperature and quality changes were monitored in real time.

[0103] After drying, passion fruit powder was obtained with a moisture content of 4.2% (determined by a moisture analyzer). The powder was pale yellow, had good flowability, and a rich aroma. It was immediately packaged in nitrogen-filled aluminum foil bags to prevent moisture absorption.

[0104] Add 5 grams of whole fruit powder to 50 mL of warm water (40℃), stir until completely dissolved without clumping, and the reconstituted pulp has a similar taste to fresh fruit pulp. HPLC analysis shows a vitamin C retention rate of ≥85% and a total phenol content retention rate of ≥90%. Sensory evaluation indicates a pale yellow color, pure flavor, and no bitterness.

[0105] Example 2: Intelligent freeze-drying application of a method for separating and freeze-drying passion fruit pulp and peel Example 2 and Example 1 both used the same batch of Tainong No. 1 passion fruit (100 kg of raw material, of which 80 kg were qualified after washing and sorting). The processing procedure is as follows: Figure 6 As shown, all pretreatment steps, including peel toughening, coating, and pulp separation system treatment, are completely consistent with those in Example 1.

[0106] The difference lies in starting with freeze-drying in step 5, which includes the following specific steps: Step 5.1: Preprocessing Add the compound freeze-drying protectant to the passion fruit pulp obtained in step 4 of Example 1 and mix well. The composition of the protectant (percentage of total mass of pulp) is: maltodextrin: 7%, trehalose: 2%, porous starch: 1.5%.

[0107] Step 5.2: Plating and quick-freezing The pretreated slurry was evenly spread into the freeze dryer tray to a thickness of 8 mm. It was then rapidly frozen at -38°C for 3 hours to ensure that the slurry was completely frozen.

[0108] Step 5.3: Intelligent freeze drying The quick-frozen material is transferred to an intelligent vacuum freeze dryer equipped with the AI ​​control system of this invention.

[0109] AI system startup: The system invokes a pre-trained drying kinetics model (trained on a large amount of historical passion fruit freeze-drying data, fully learning its sugar-acid properties, glass transition behavior, etc.). Dynamic collaborative control is then implemented, including: During the sublimation drying stage: The AI ​​system collects parameters such as material temperature, shelf temperature, and system vacuum level in real time and inputs them into the model. The model calculates and dynamically outputs the current material's collapse temperature safety threshold (predicted value -16℃, safety threshold set at -20℃). Based on this, the control system precisely controls the shelf temperature, bringing it close to this safety threshold at the maximum allowable heating rate, thereby greatly accelerating the sublimation rate while ensuring product quality (no collapse). Simultaneously, the model adjusts the system vacuum level within the range of 10-25 Pa based on the predicted mass transfer resistance to optimize mass transfer efficiency.

[0110] During the analytical drying stage: Once the model predicts that most of the free water has been removed, the system enters the analytical drying phase. Based on the real-time predicted rate of change of residual moisture, the AI ​​system dynamically and gradually increases the shelf temperature to 48°C, while ensuring that the core temperature of the material remains below the safe threshold of the glass transition temperature calculated by the model, effectively preventing product melting or quality deterioration.

[0111] Step 5.4: Intelligent Endpoint Determination During the drying process, the AI ​​system continuously predicts the real-time residual moisture of the material using a model. When the model's predicted value stably reaches and remains at 3.5% (the target range is 3%-5%), the system automatically determines that the drying endpoint has been reached and immediately terminates the drying process.

[0112] After drying, the total drying time was 20 hours. The obtained passion fruit powder was tested and found to have a moisture content of 3.5%. 5 grams of the powder were added to 50 mL of warm water (40℃), dissolving rapidly without clumping. The rehydration properties were superior to those in Example 1, and the reconstituted pulp had a taste similar to fresh pulp. HPLC analysis showed a vitamin C retention rate of ≥91% and a total phenol content retention rate of ≥94%. Sensory evaluation revealed a bright yellow color, a rich and pure flavor, and no bitterness.

[0113] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for the present invention. Further modifications can be readily implemented by those skilled in the art.

Claims

1. A passion fruit pulp separation system characterized by, The application relates to a guava cutting device. The guava cutting device comprises: a guava feeding channel arranged to keep guavas in a predetermined posture and sequentially pass through the guava feeding channel under the action of gravity; a piercing and stirring unit arranged on the side of the guava feeding channel and used for piercing and stirring the guavas passing through the guava feeding channel; a cutting unit arranged in the guava feeding channel at a position downstream of the piercing and stirring unit; the piercing and stirring unit comprises: a piercing rod provided with a piercing head at the front end; a stirring part sleeved on the piercing rod, the stirring part being configured to expand radially from a folded state to an expanded structure under the action of centrifugal force; a vibration mechanism in transmission connection with the piercing rod and used for driving the piercing rod to generate high-frequency micro-vibration; a rotating mechanism in transmission connection with the piercing rod and used for driving the piercing rod to rotate around the axis thereof; 2. The passion fruit pulp separation system according to claim 1, characterized in that, a piercing motion mechanism fixedly connected with the vibration mechanism and the rotating mechanism and used for driving the piercing rod, the vibration mechanism and the rotating mechanism to make linear reciprocating motion as a whole relative to the guava feeding channel. The piercing rod is provided with an axial limiting section close to the piercing head, and the stirring part is arranged on the axial limiting section of the piercing rod, and the expanded structure of the stirring part comprises: a first sleeve and a second sleeve which are axially spaced apart and sleeved on the axial limiting section of the piercing rod and are in sliding fit with the piercing rod through a key groove structure, so that the sleeves can slide axially along the piercing rod while synchronously rotating with the piercing rod; a plurality of flexible ribs which are uniformly arranged in the circumferential direction and connected between the first sleeve and the second sleeve to form a tubular framework; a return spring which is sleeved on the periphery of the piercing rod and located between the first sleeve and the second sleeve, and the two ends of the return spring are respectively abutted on the opposite end faces of the two sleeves; 3. The passion fruit pulp separation system according to claim 2, characterized in that, when the piercing rod rotates so that the centrifugal force overcomes the elastic force of the return spring, the first sleeve and the second sleeve are close to the compressed spring, and the plurality of flexible ribs are expanded from the folded state to the radial outside to form the expanded structure for stirring. The diameter of the axial limiting section is smaller than the diameter of the piercing rod, the diameter of the axial limiting section is matched with the inner diameters of the first sleeve and the second sleeve to form a transition fit or a clearance fit; after the first sleeve and the second sleeve are sleeved on the axial limiting section, the outer surface of the first sleeve and the second sleeve is flush or slightly lower than the outer surface of the adjacent section of the piercing rod, so that the stirring part forms an approximately smooth rod profile in the folded state; 4. The passion fruit pulp separation system according to claim 2, characterized by, the piercing head is detachably connected with one end of the piercing rod through a threaded structure, and after being screwed, the piercing head constitutes axial mechanical limiting of the first sleeve and the second sleeve sleeved on the axial limiting section, preventing the sleeves from axially moving or being separated from the piercing rod.

5. The passion fruit pulp separation system according to any one of claims 1 to 4, characterized in that, At least one ball is fixedly arranged on the flexible rib of the stirring part; when the stirring part comprises the first sleeve, the second sleeve and the plurality of flexible ribs, the ball is arranged at the middle part of the flexible rib. The guava cutting device further comprises: a guava positioning unit arranged in the guava feeding channel and located above the piercing and stirring unit and used for accurately positioning the guavas before the piercing operation; the guava positioning unit comprises: elastic guide parts symmetrically arranged on the inner walls of the left and right sides of the guava feeding channel, and a V-shaped or arc-shaped positioning groove which is gradually narrowed from top to bottom is formed between the elastic guide parts on the left and right sides. The positioning block is provided below the elastic guide component, controlled by the driving mechanism, capable of extending into the discharging channel to block the already centered passion fruit from falling further, so as to make it stay at the preset waiting-for-piercing station, and quickly retract after the piercing and stirring operation is completed to release the passion fruit to continue falling.

6. The passion fruit pulp separation system according to claim 5, characterized by, The positioning block is provided below the elastic guide component, controlled by the driving mechanism, capable of extending into the discharging channel to block the already centered passion fruit from falling further, so as to make it stay at the preset waiting-for-piercing station, and quickly retract after the piercing and stirring operation is completed to release the passion fruit to continue falling. The positioning block is provided below the elastic guide component, controlled by the driving mechanism, capable of extending into the discharging channel to block the already centered passion fruit from falling further, so as to make it stay at the preset waiting-for-piercing station, and quickly retract after the piercing and stirring operation is completed to release the passion fruit to continue falling.

7. The passion fruit pulp separation system according to claim 1, characterized by, The control unit is configured to: when the passion fruit moves to the processing station, the piercing mechanism drives the piercing rod to move forward, so that the piercing rod pierces and penetrates the passion fruit, and the stirring part is located in the passion fruit; the rotating mechanism drives the piercing rod to rotate, the stirring part expands to form an expanding stirring head under the action of centrifugal force, and the vibration mechanism drives the piercing rod to produce high-frequency micro-vibration.

8. The passion fruit pulp separation system according to claim 7, characterized by, The control unit is further configured to: a) Real-time monitoring of the motor load current of the rotating mechanism, when the load current is detected to enter the sustained decline channel from the peak value, it is determined that the pulp enters the rapid liquefaction period, and the rotation speed and vibration parameters are dynamically adjusted based on the current decline rate to optimize the liquefaction efficiency; b) When the load current drops to the stable interval, the fluctuation amplitude of the load current and the frequency spectrum characteristics of the vibration signal are monitored simultaneously; when the following two conditions are met at the same time and last for a preset time, it is determined that the pulp has been sufficiently liquefied: The fluctuation amplitude of the load current is less than the first set threshold value; The amplitude change rate of the main frequency of the vibration signal is less than the second set threshold value, and the low-frequency impact component decays to the background noise level; c) Once the liquefaction endpoint is reached, the corresponding mechanism is turned off in the order of first stopping the vibration mechanism and then stopping the rotating mechanism, the piercing rod is controlled to exit, and the ring transmission mechanism is started to step one station.

9. The passion fruit pulp separation system according to claim 1, characterized by, It further comprises an intelligent freeze-drying unit, which performs the following steps: S1, a pretreatment step: adding a composite freeze-drying protective agent to the passion fruit slurry separated by the passion fruit pulp separation system of claim 1 and mixing uniformly, the composite freeze-drying protective agent includes the following components with a total mass percentage of 5%-8% of malt dextrin, 1%-3% of trehalose and 1%-2% of porous starch; S2, a loading and quick-freezing step: the pretreated slurry is laid flat on the tray with a thickness of 5-10 millimeters, and is quickly frozen at a temperature of-35℃ to-40℃ for 2-4 hours; S3, an intelligent freeze-drying step: under vacuum environment, the process parameters of the freeze-drying process are dynamically controlled by an AI control system; wherein the AI control system performs the following operations: S31, real-time acquisition of process parameters in the freeze-drying process, the process parameters including material temperature, system vacuum degree and cold trap temperature; S32, input the process parameters into a pre-trained drying kinetics model, which is a machine learning model trained based on historical freeze-drying process data, material property data, and final product quality data; S33, based on the output of the model, dynamically and cooperatively adjust the temperature curve of the heating shelf and the vacuum degree control curve of the system; Wherein, in the sublimation drying stage, the shelf temperature is controlled to approach the material collapse temperature safety threshold calculated by the model in real time at the maximum allowed rate, which is the material dry layer collapse temperature minus 3-5℃; In the desorption drying stage, based on the material residual moisture change rate predicted by the model, the shelf temperature is gradually increased to 40-50℃, while ensuring that the material core temperature is lower than the glass transition temperature safety threshold; S4, drying endpoint determination: when the model predicts that the residual moisture reaches 3%-5% by mass fraction, the drying process is automatically terminated.

10. A method for separating and freeze-drying the pulp of passion fruit using the system for separating the pulp of passion fruit according to claim 1, characterized in that, Comprising the following steps: Step 1, washing passion fruit to remove surface impurities; Then sorting; Step 2, immerse the sorted passion fruit in a calcium chloride solution with a mass fraction of 1.0%-1.5%, soak for 10-15 minutes under normal pressure; after taking out, carry out film coating treatment, use a chitosan solution with a mass fraction of 1.0% containing 0.3%-0.5% glycerol to form a flexible protective film; Step 3, send the passion fruit treated in step 2 into the passion fruit pulp separation system of claim 1, and execute the following sub-steps: accurately center and position the passion fruit at the puncture work station by the positioning unit; control the puncture rod to pierce into the passion fruit, start the rotating mechanism and high-frequency vibration mechanism, and cooperatively act at a rotating speed of 300-600 rpm and a vibration frequency of 200-500 Hz for 60-120 seconds to fully liquefy the pulp; based on intelligent monitoring of load current and vibration signals, judge the liquefaction completion degree of the pulp, and stop processing in sequence after reaching the threshold; deliver the passion fruit to the cutting unit for halving cutting, and make the liquefied fruit pulp flow out naturally; Step 4, centrifugal separation treatment of the flowing out pulp slurry to separate out complete seeds, pulp fibers and peels, and obtain passion fruit slurry; Step 5, freeze-drying the passion fruit slurry to obtain passion fruit whole fruit powder.

11. The method of separating and freeze-drying passion fruit pulp according to claim 10, characterized by, Step 5 specifically comprises the following sub-steps: Step 5.1, pretreatment: add a composite freeze-drying protective agent to the passion fruit slurry obtained in step 4 and mix uniformly, the composite freeze-drying protective agent comprises the following components with a total mass percentage of 5%-8% of malt dextrin, 1%-3% of trehalose and 1%-2% of porous starch; Step 5.2, tray loading and quick freezing: spread the pretreated slurry on the tray with a thickness of 5-10 mm, and quick-freeze for 2-4 hours under the condition of-35℃ to-40℃; Step 5.3, intelligent freeze-drying: transfer the quick-frozen material to a vacuum freeze-drying machine, and execute the following operations by the AI control system: Real-time acquisition of material temperature, system vacuum degree and cold trap temperature process parameters; Input the process parameters into a pre-trained drying kinetics model, which is trained based on historical freeze-drying data and material property data; Based on the drying kinetics model, the temperature of the heating shelf and the system vacuum degree are dynamically adjusted: In the sublimation drying stage, the shelf temperature is controlled to approach the material collapse temperature safety threshold calculated by the drying kinetics model in real time at the maximum allowed rate, which is the material dry layer collapse temperature minus 3-5℃; In the analytical drying stage, based on the model predicted material residual moisture change rate, the shelf temperature is gradually increased to 40-50℃, while ensuring that the core temperature of the material is lower than the glass transition temperature safety threshold; Step 5.4, end point determination: when the drying kinetics model predicts that the residual moisture reaches 3%-5% by mass fraction, the drying is automatically terminated, and the passion fruit whole fruit powder is obtained.

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