Production process of rosa roxburghii tratt freeze-dried tablets

Abstract

The invention relates to the technical field of vacuum freeze-drying processing of food, and particularly discloses a production process of roxburgh rose freeze-dried slices, which comprises the following steps: cleaning roxburgh rose, cutting, removing seeds, cleaning for the second time, and airing surface moisture; blanching the roxburgh rose slices, air-drying the roxburgh rose slices, and soaking the roxburgh rose slices in a sugar solution; performing pre-freezing treatment on the soaked roxburgh rose slices; the pre-frozen roxburgh rose slices are put into a vacuum freeze-drying machine, vacuum sublimation drying and vacuum desorption drying are conducted in sequence, the roxburgh rose freeze-dried slices are obtained, meanwhile, the matched vacuum freeze-drying machine is disclosed and comprises a drying bin, a liftable shelf, a fixed shelf, a slidable tray frame, a freeze-drying tray with a lifting pore plate and a corresponding vacuum pipeline, by optimizing the sugaring process and freeze-drying parameters and combining the up-and-down synchronous water vapor pumping and discharging design of the equipment, the problems of non-uniform sweetness, low heat and mass transfer efficiency of the equipment and the like in the traditional process are solved, thermosensitive nutrition retention of the roxburgh rose and the crispness of the finished product are both considered, and the production efficiency and the product quality are both improved.

Description

Technical Field

[0001] The invention relates to the technical field of food vacuum freeze-drying processing, and in particular to a production process of roxburghii freeze-dried slices. Background Art

[0002] As a specialty fruit and vegetable rich in vitamin C, polyphenols and other active ingredients, the processed products of sea buckthorn are gradually developing towards freeze-drying technology due to the need to retain nutrients. Vacuum freeze-drying technology, with its low-temperature dehydration characteristics, can maximize the retention of heat-sensitive nutrients and original forms in sea buckthorn, making it the preferred process for deep processing of sea buckthorn.

[0003] In the current processing of sea buckthorn freeze-dried slices, raw material processing mostly includes cleaning, cutting, seeding, secondary cleaning and surface drying steps; blanching to inactivate enzymes and candied color protection are common pretreatment processes, and sugars such as sucrose and maltose are commonly used for candied, and the solid-liquid ratio and temperature are set based on experience; pre-freezing is mostly carried out in a low-temperature environment, and vacuum freeze drying is generally divided into two stages: sublimation drying and analytical drying. Dehydration is achieved by controlling the vacuum degree and temperature. The vacuum freeze dryer used for freeze-drying sea buckthorn slices is mainly based on the traditional structure. The vacuum freeze dryer is usually equipped with a drying chamber, a shelf mounting rack, a fixed shelf and a tray rack. The freeze-drying tray is used to carry materials. The vacuum pipeline is responsible for removing the water vapor generated during the drying process, and relies on the shelf to conduct heat to remove the water vapor through a single pipeline.

[0004] However, the existing sea buckthorn freeze-drying process and equipment still have several obvious limitations in practical applications. On the one hand, the sugar solution used in the conventional impregnation process has a relatively simple composition and limited penetration efficiency, resulting in uneven sweetness distribution of the finished product and no obvious improvement in taste. On the other hand, the materials in the traditional freeze dryer are stacked and the shelf spacing is fixed, resulting in low heat and mass transfer efficiency and a long drying cycle; especially in the water vapor discharge stage, the water vapor escape path inside the tray is long and the resistance is large, which can easily cause local rewetting or uneven drying, ultimately affecting the moisture content consistency and crispness of the product. In addition, ordinary freeze-drying trays lack internal structural optimization, the contact thermal resistance between the material and the shelf is large, and the water vapor at the sublimation interface is difficult to remove in time, further limiting the improvement of freeze-drying efficiency and quality. Summary of the Invention

[0005] In view of the technical defects existing in the background technology, the present invention proposes a production process of a roxburghii freeze-dried tablet, which solves the above technical problems and meets the actual needs. The specific technical solution is as follows: A production process for freeze-dried roxburghii slices comprises the following steps: S1. Select prickly pear with no pests and suitable maturity as raw material, wash the prickly pear, and then cut into 3-5mm prickly pear slices, remove the seeds and wash the prickly pear slices for the second time, and then dry the surface moisture; S2. Place the Rosa rugosa slices in 70-80°C hot water for 2-3 min, then remove the Rosa rugosa slices, air-dry the surface moisture, and immerse the blanched Rosa rugosa slices in the sugar solution for 1-2 h; S3. Place the roxburghii slices soaked in sugar solution in a freezer and pre-freeze at -30°C for 12 hours; S4. Place the pre-frozen roxburghii slices into a vacuum freeze dryer for vacuum freeze drying. After vacuum freeze drying is completed, freeze-dried roxburghii slices are obtained.

[0006] As a further technical solution of the present invention, in step S2, the solid-liquid ratio of the roxburghii slices to the sugar solution is 1:(1.5-2), the soaking temperature is 50-60°C, and the components of the sugar solution include: 20-30% maltooligosaccharides, 10-15% xylitol, 0.010-0.020% sucralose, and the balance is water.

[0007] As a further technical solution of the present invention, in step S4, the vacuum freeze-drying process is: the pre-frozen roxburghii slices are placed in a vacuum freeze dryer and sequentially subjected to vacuum sublimation drying and vacuum analytical drying, the vacuum degree of the vacuum sublimation drying being 20-25 Pa, the temperature being 25-30° C., the moisture content of the vacuum sublimation dried roxburghii slices being 10±2%, the vacuum degree of the vacuum analytical drying being 5-20 Pa, the temperature being 55-60° C., and the moisture content of the vacuum analytical dried roxburghii slices being 5±2%.

[0008] As a further technical solution of the present invention, in step S4, the structure of the vacuum freeze dryer includes a vacuum freeze dryer body, a drying chamber is provided inside the vacuum freeze dryer body, a shelf mounting rack connected to the vacuum freeze dryer body is provided inside the drying chamber, a plurality of fixed shelves are equidistantly provided on the left and right inner surfaces of the shelf mounting rack along the height direction of the vacuum freeze dryer body, a lifting shelf that can move up and down on the inner surface of the shelf mounting rack is provided above each of the fixed shelves in parallel, a tray rack is provided between the fixed shelves on the left and right inner surfaces of the shelf mounting rack, the top of the tray rack is slidably connected to the shelf mounting rack, the bottom of the tray rack is slidably connected to the vacuum freeze dryer body, a plurality of freeze-drying trays are provided on the tray rack, and the freeze-drying trays are located between the lifting shelf and the fixed shelf and are equidistantly distributed along the length direction of the fixed shelf; A lifting hole plate movably connected to the inner wall of the freeze-drying tray is provided inside the freeze-drying tray, and mounting side plates are symmetrically provided on the left and right sides of the freeze-drying tray. Several lifting mechanisms respectively connected to the outer wall of the freeze-drying tray and the mounting side plates are provided below the mounting side plates. The lifting mechanisms are symmetrically arranged on the left and right sides of the freeze-drying tray, and a first magnetic strip is provided on the rear outer wall of the freeze-drying tray. The several lifting mechanisms are connected to the corresponding side of the lifting hole plate, and the lower surface of the lifting shelf is provided with a vacuum pipeline corresponding to the position of the freeze-drying tray.

[0009] As a further technical solution of the present invention, the left and right inner surfaces of the shelf mounting frame are provided with a plurality of sliding grooves arranged in a matrix, and the rear end of the lifting shelf is correspondingly arranged in the same sliding groove at the same horizontal height, and a freely rotatable screw is longitudinally penetrated in the sliding groove in the same row, and the upper end of the screw is placed on the top of the shelf mounting frame, and the lower end of the screw longitudinally penetrates the sliding groove in the same row in turn and is threadedly connected to the rear end of the lifting shelf in the sliding groove, the upper end of the screw is provided with a first bevel gear, and the top of the shelf mounting frame is provided with a motor, and the power output of the motor is connected to the second bevel gear that can mesh and rotate with the first bevel gear.

[0010] As a further technical solution of the present invention, the tray rack includes a sliding rack and several groups of mounting base plates symmetrically arranged on the left and right sides of the sliding rack and corresponding to the positions of the vacuum pipelines, a U-shaped tray mounting rack correspondingly arranged above each group of mounting base plates, and a telescopic member arranged between the mounting base plate and the tray mounting rack. The top surface of the tray mounting rack is symmetrically provided with mounting grooves, and the lower surface of the mounting side plate of the freeze-drying tray is provided with a sliding strip that can cooperate with the sliding in the mounting groove. The rear side of the tray mounting rack is provided with a magnetic fixing groove that cooperates with the first magnetic strip, and the magnetic fixing groove is provided with a second magnetic strip that can be magnetically attracted to the first magnetic strip.

[0011] As a further technical solution of the present invention, the telescopic part includes a lifting cylinder and a first spring. A limit lifting groove corresponding to the position of the telescopic part is provided inside the mounting base. The upper end of the lifting cylinder is connected to the lower surface of the tray mounting frame. The lower end of the lifting cylinder is placed in the limit lifting groove and can slide in the limit lifting groove. The first spring is arranged in the limit lifting groove and its two ends are respectively connected to the inner wall of the top of the lifting cylinder and the inner wall of the bottom of the limit lifting groove.

[0012] As a further technical scheme of the present application, the lifting mechanism comprises an L-shaped plate connected with the mounting side plate and the outer sidewall of the freeze-drying tray at two ends respectively, a guide wheel penetratingly arranged inside the sidewall of the freeze-drying tray and capable of freely rotating, a fixed pulley arranged below the mounting side plate, a press column arranged inside the L-shaped plate and capable of lifting and sliding, and a flexible rope transmitting and connecting the guide wheel and the fixed pulley.

[0013] As a further technical scheme of the present application, the L-shaped plate is internally provided with a lifting limiting sliding groove, the press column penetrates through the mounting side plate and is arranged inside the lifting limiting sliding groove at the lower end and above the mounting side plate at the upper end, the lower end of the press column is connected with a sliding base capable of limiting sliding in cooperation with the lifting limiting sliding groove, the two ends of the flexible rope are respectively connected with the sliding base of the press column and the upper surface edge position of the lifting hole plate, the lifting limiting sliding groove is internally provided with a second spring, and the two ends of the second spring are respectively connected with the bottom of the sliding base and the groove bottom of the lifting limiting sliding groove.

[0014] As a further technical scheme of the present application, the sidewall of the freeze-drying tray is penetratingly provided with a plurality of through grooves distributed at equal intervals, the bottom of the freeze-drying tray is symmetrically provided with a fixed bottom plate, the four corner positions of the lifting hole plate are correspondingly provided with guide rods penetratingly arranged, the upper end of the guide rod is arranged above the lifting hole plate, and the lower end is connected with the fixed bottom plate, the surface of the lifting hole plate is penetratingly provided with vertical cylinders distributed in a matrix, and the lifting hole plate is penetratingly provided with through holes distributed in a matrix between adjacent vertical cylinders. The lower surface of the lifting shelf is provided with a pipeline groove matched with the vacuum pipeline, the vacuum pipeline is arranged in the pipeline groove, the vacuum pipeline comprises a main pipe, a plurality of long branch pipes and short branch pipes respectively communicated with the main pipe, the long branch pipes are correspondingly arranged with the vertical cylinders, the inner diameter of the vertical cylinder is greater than the outer diameter of the long branch pipe, and the short branch pipes are uniformly arranged between adjacent long branch pipes.

[0015] The present application has the following beneficial effects: The present invention is in production technology, by optimizing the sugar solution formula and the impregnation process, which can promote the sugar solution to evenly penetrate into the inside of the roxburghii slices, solves the problem of uneven sweetness and poor taste of the finished products of the traditional process, and combines the blanching and freeze-drying processes to better retain the heat-sensitive nutrients in the roxburghii, taking into account both taste and nutrition. In terms of equipment design, the liftable shelf of the vacuum freeze dryer cooperates with the fixed shelf and is equipped with a slidable tray rack, which improves the convenience of material loading and unloading; the adjustable design of the lifting orifice plate in the freeze-drying tray, combined with the long and short branch pipes of the vacuum pipeline, can synchronously pump out water vapor from the upper and lower sides of the roxburghii slices, shorten the water vapor escape path, avoid local rewetting, and ensure the consistency of product moisture content and crispness. In addition, the freeze-drying tray can move up and down through the telescopic part, can fit closely with the lifting shelf and the fixed shelf, improve heat transfer efficiency, effectively shorten the drying cycle, and achieve a dual improvement in the quality and production efficiency of the roxburghii freeze-dried slices. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is one of the cross-sectional views of the internal structure of the vacuum freeze dryer of the present invention.

[0017] Figure 2 The second cross-sectional view of the internal structure of the vacuum freeze dryer of the present invention.

[0018] Figure 3 Schematic diagram of the positional relationship between the lifting shelf, fixed partition and freeze-drying tray of the present invention.

[0019] Figure 4 For the Figure 3 A partial enlarged schematic diagram of the AA point in the middle.

[0020] Figure 5 It is a schematic diagram of the three-dimensional structure of the freeze-drying tray of the present invention.

[0021] Figure 6 This is a cross-sectional view of the internal structure of the freeze-drying tray of the present invention.

[0022] Figure 7 This is one of the schematic diagrams showing the lifting state of the lifting shelf of the present invention.

[0023] Figure 8 This is the second schematic diagram of the lifting state of the lifting shelf of the present invention.

[0024] Figure 9 It is a schematic diagram of the L-shaped plate structure of the present invention.

[0025] Figure 10 Schematic diagram of the structure of the tray rack of the present invention.

[0026] Reference numerals: 1- Vacuum freeze dryer body; 11- Drying chamber; 12- Shelf mounting bracket; 121- Sliding slot; 13- Lifting shelf; 14- Fixed shelf; 15- Motor; 16- First bevel gear; 17- Second bevel gear; 18- Lead screw; 2-tray rack; 21-sliding rack; 22-tray mounting rack; 221-mounting slot; 222-magnetic fixing slot; 23-mounting base plate; 231-limiting lifting slot; 24-telescopic member; 241-lifting cylinder; 242-first spring; 3-freeze-drying tray; 31-lifting hole plate; 311-through hole; 312-vertical cylinder; 32-mounting side plate; 321-sliding bar; 33-fixed bottom plate; 34-guide rod; 35-through slot; 36-first magnetic strip; 4 - lifting mechanism; 41 - L-shaped plate; 411 - lifting limit slide; 42 - guide wheel; 43 - mounting frame; 44 - fixed pulley; 45 - pressing column; 451 - sliding base; 46 - flexible rope; 47 - second spring; 5-vacuum pipe; 51-main pipe; 52-long branch pipe; 53-short branch pipe. DETAILED DESCRIPTION

[0027] The following describes the implementation of the present invention in conjunction with relevant embodiments. The implementation of the present invention is not limited to the following embodiments, and the present invention relates to relevant necessary components in this technical field and should be regarded as a well-known technology in this technical field, which can be known and mastered by technical personnel in this technical field.

[0028] A production process for freeze-dried roxburghii slices comprises the following steps: S1. Select prickly pear with no pests and suitable maturity as raw material, wash the prickly pear, and then cut into 3-5mm prickly pear slices, remove the seeds and wash the prickly pear slices for the second time, and then dry the surface moisture; S2. Place the Rosa rugosa slices in 70-80 ° C hot water for 2-3min, then remove the Rosa rugosa slices, air-dry the surface moisture, and immerse the blanched Rosa rugosa slices in sugar solution for 1-2h; S3. Place the roxburghii slices soaked in sugar solution in a freezer and pre-freeze at -30°C for 12 hours; S4. Place the pre-frozen roxburghii slices into a vacuum freeze dryer for vacuum freeze drying. After vacuum freeze drying is completed, freeze-dried roxburghii slices are obtained.

[0029] In step S1 of the present invention, the following steps are performed: selecting a roxburghii that is free of pests and diseases and has an appropriate degree of maturity, thereby ensuring the high quality of the raw materials from the source; washing and removing impurities, and then cutting into 3-5 mm roxburghii slices. This thickness can not only avoid uneven subsequent drying caused by being too thick, but also avoid damage caused by being too thin during processing, but also facilitates nutrient retention and shape maintenance; removing seeds can remove astringent impurities, and secondary washing can further remove residues; drying surface moisture can prevent dilution of the treatment liquid during subsequent blanching and sugaring, thereby ensuring process effects; step S2 adopts 70-80°C hot water for blanching for 2-3 minutes, accurately achieving enzyme inactivation and color protection, inhibiting oxidative browning of the roxburghii, and avoiding long-term high-temperature treatment to destroy heat-sensitive components such as vitamin C; sugaring is performed for 1-2 hours after the surface moisture is air-dried, thereby improving the penetration efficiency of the sugar solution, and laying a foundation for improving the sweetness uniformity of the finished product and optimizing the taste. Step S3 pre-freezes the slices at -30°C for 12 hours to form uniform, fine ice crystals, ensuring smooth sublimation of the ice crystals during subsequent vacuum freeze-drying, preserving the integrity of the slices and preventing excessive ice crystals from collapsing after freeze-drying. Step S4 uses vacuum freeze-drying to sublimate the ice crystals formed by pre-freezing, maximizing the retention of the active nutrients and original flavor of the slices, ultimately yielding freeze-dried slices with an appropriate moisture content and good crispness.

[0030] As one of the preferred embodiments of the present invention, in step S2, the solid-liquid ratio of the roxburghii slices and the sugar solution is 1:1.5-2, the immersion temperature is 50-60°C, and the components of the sugar solution include: 20-30% maltooligosaccharides, 10-15% xylitol, 0.010-0.020% sucralose, and the balance is water.

[0031] Specifically, the solid-liquid ratio of the sea buckthorn slices and the sugar solution is preferably 1:2, the soaking temperature is preferably 55°C, and the components of the sugar solution are preferably: 25% maltooligosaccharide, 12.5% ​​xylitol, 0.015% sucralose, and the balance is water.

[0032] Step S2, from the perspective of taste optimization, effectively solves the problem of uneven sweetness and poor taste of traditional candied products. The preferred solid-liquid ratio of 1:2 ensures that the sea buckthorn slices are completely immersed in the sugar solution, avoiding local differences in sweetness due to insufficient contact, while also avoiding excessive sugar solution that causes waste of raw materials and the burden of subsequent drying. The immersion temperature is preferably 55°C, which can accelerate the movement of sugar molecules, improve penetration efficiency, shorten the immersion time, and prevent the destruction of heat-sensitive nutrients such as vitamin C in the sea buckthorn due to excessive temperature, thus balancing the penetration effect and nutritional protection.

[0033] The sugar solution formula takes into account flavor, health, and stability. Maltooligosaccharides provide mild sweetness and a certain degree of moisture retention to prevent the finished product from overdrying. Xylitol reduces the overall sugar content, adapting to health needs and enhancing the crispness of the freeze-dried tablets. Sucralose (as a high-intensity sweetener, a small amount can supplement the sweetness, reduce the total amount of sugar, and prevent excessive sugar from masking the original flavor of the sea buckthorn. The three ingredients work together to ensure that the finished product has a uniform sweetness and a refreshing taste, while retaining the original nutrients of the sea buckthorn.

[0034] As one of the preferred embodiments of the present invention, in step S4, the vacuum freeze-drying process is: the pre-frozen roxburghii slices are placed in a vacuum freeze dryer and sequentially subjected to vacuum sublimation drying and vacuum analytical drying, the vacuum degree of the vacuum sublimation drying being 20-25 Pa, the temperature being 25-30° C., the moisture content of the vacuum sublimation dried roxburghii slices being 10±2%, the vacuum degree of the vacuum analytical drying being 5-20 Pa, the temperature being 55-60° C., and the moisture content of the vacuum analytical dried roxburghii slices being 5±2%.

[0035] The vacuum freeze-drying process in step S4 consists of two stages, ensuring efficient water removal while preserving the nutrients and morphology of the sea buckthorn slices to the greatest extent possible. During the sublimation drying stage, a vacuum of 20-25 Pa (1.5-2.5 Pa) maintains a low-temperature, low-pressure environment to prevent ice crystals from melting and causing the slices to collapse. A temperature of 25-30°C provides the heat required for ice crystal sublimation while also protecting the slices from heat-sensitive components (such as vitamin C). Maintaining the moisture content at 10 ± 2% during this stage prevents excess moisture from increasing the burden of subsequent analytical analysis and prevents brittleness and damage caused by overdrying, laying a solid foundation for analytical drying.

[0036] The analytical drying stage focuses on removing the bound water inside the sea buckthorn slices. A lower vacuum degree of 5-20pa can accelerate the desorption of bound water. The temperature of 55-60℃ can increase the water diffusion rate and further reduce the moisture content to 5±2%, which can ensure the crispy taste of the sea buckthorn freeze-dried slices, avoid moisture regain and softening due to too high a moisture content, or dry and hard taste due to too low a moisture content, thereby achieving dual optimization of drying efficiency and product quality.

[0037] As one of the preferred embodiments of the present invention, Figures 1 to 10As shown, in step S4, the structure of the vacuum freeze dryer includes a vacuum freeze dryer body 1, a drying chamber 11 is provided inside the vacuum freeze dryer body 1, and a shelf mounting rack 12 connected to the vacuum freeze dryer body 1 is provided inside the drying chamber 11, and a plurality of fixed shelves 14 are equidistantly provided on the left and right inner surfaces of the shelf mounting rack 12 along the height direction of the vacuum freeze dryer body 1, and a lifting shelf 13 that can move up and down on the inner surface of the shelf mounting rack 12 is provided above each of the fixed shelves 14 in parallel, and a tray rack 2 is provided between the fixed shelves 14 on the left and right inner surfaces of the shelf mounting rack 12, respectively, the top of the tray rack 2 is slidably connected to the shelf mounting rack 12, and the bottom of the tray rack 2 is slidably connected to the vacuum freeze dryer body 1, and a plurality of freeze-drying trays 3 are provided on the tray rack 2, and the freeze-drying trays 3 are located between the lifting shelf 13 and the fixed shelf 14 and are equidistantly distributed along the length direction of the fixed shelf 14; The freeze-drying tray 3 is provided with a lifting hole plate 31 movably connected to the inner wall of the freeze-drying tray 3, and the left and right sides of the freeze-drying tray 3 are symmetrically provided with mounting side plates 32. Below the mounting side plates 32 are provided with a number of lifting mechanisms 4 respectively connected to the outer wall of the freeze-drying tray 3 and the mounting side plates 32. The lifting mechanisms 4 are symmetrically arranged on the left and right sides of the freeze-drying tray 3, and a first magnetic strip 36 is provided on the rear outer wall of the freeze-drying tray 3. The several lifting mechanisms 4 are connected to the corresponding side of the lifting hole plate 31, and the lower surface of the lifting shelf 13 is provided with a vacuum pipeline 5 corresponding to the position of the freeze-drying tray 3.

[0038] The vacuum freeze dryer used in the process of the present invention has a structural design centered around improving heat and mass transfer efficiency and operational convenience. The various components work together to ensure the uniformity of drying the sea buckthorn slices. The drying chamber 11 inside the vacuum freeze dryer body 1 provides a closed drying space, and the shelf mounting frame 12 serves as a supporting base for the lifting shelf 13 and the fixed partition 14 and the freeze-drying tray 3. The fixed shelf 14 is equidistantly arranged in the height direction and is parallel to the lifting shelf 13 that can move up and down above. By adjusting the position of the lifting shelf 13 and pressing down the freeze-drying tray 3, the top of the freeze-drying tray 3 is in close contact with the lifting shelf 13, and the bottom of the freeze-drying tray 3 is in close contact with the fixed shelf 14. At the same time, the contact heat transfer effect between the material and the shelf can be optimized, avoiding the uneven heat transfer problem caused by traditional fixed spacing.

[0039] The tray rack 2 is located between the fixed shelves 14 on both sides. Its top is connected to the shelf mounting frame 12, and its bottom is connected to the vacuum freeze dryer body 1 in a sliding manner, which facilitates the overall pulling and loading and unloading of the freeze-drying trays 3, improving operational efficiency. The freeze-drying trays 3 are evenly spaced between the lifting shelf 13 and the fixed shelf 14. The lifting orifice plate 31 inside the freeze-drying tray 3 is movable and adjustable. In conjunction with the symmetrical lifting mechanism 4 on both sides, it can change the material placement height and create a channel for water vapor discharge. The first magnetic strip 36 can fix the position of the freeze-drying tray 3 to prevent displacement during the drying process. The vacuum pipe 5 on the lower surface of the lifting shelf 13 corresponds to the freeze-drying tray 3, which can accurately remove the water vapor generated by drying, further ensuring drying efficiency and uniformity.

[0040] It should be noted that the vacuum freeze dryer of the present invention should also include a vacuum generating and regulating component, a water vapor capture system, a temperature control auxiliary component, and a sealing structure. The vacuum generating and regulating component contains a two-stage rotary vane vacuum pump group, which is connected to the drying chamber 11 through a corrosion-resistant pipe. In addition, it needs to be connected to the vacuum pipeline 5, and is equipped with a vacuum regulating valve and a high-precision vacuum gauge to maintain the vacuum degree of the drying chamber 11 stable in real time. The water vapor capture system is installed between the drying chamber 11 and the vacuum pump of the vacuum generating and regulating component. The temperature control auxiliary component includes a platinum resistance temperature sensor installed on the heat exchange pipeline between the lifting shelf 13 and the fixed shelf 14, and a temperature control valve linked to the refrigeration / heating unit to control the shelf temperature; the sealing structure is a silicone rubber sealing strip on the edge of the door of the drying chamber 11 and a manual / pneumatic locking device to prevent vacuum leakage; each component works together to ensure that the freeze-drying process is stable and efficient.

[0041] In addition, it also includes a control system that integrates a programmable logic controller (PLC) and a human-machine interface (HMI) to automatically control and monitor the entire freeze-drying process (such as shelf temperature, vacuum level in the drying chamber 11, time of each stage, etc.) to ensure accurate execution of process parameters and the stability and consistency of product quality. It should be noted that heat exchange pipelines are provided inside the lifting shelf 13 and the fixed shelf 14 of the present invention. The heat exchange pipelines of the lifting shelf 13 and the fixed shelf 14 are connected through external pipelines, so that the heat exchange pipelines of the lifting shelf 13 and the fixed shelf 14 are connected. The heat exchange pipelines need to be connected to the refrigeration unit and the heating unit arranged on the vacuum freeze dryer structure, and the heat exchange pipelines are connected to the refrigeration unit and the heating unit respectively by setting external valve switching.

[0042] As one of the preferred embodiments of the present invention, Figure 1 、 Figure 2 、 Figure 3 、 Figure 7 、 Figure 8As shown, the left and right inner surfaces of the shelf mounting frame 12 are provided with a plurality of sliding grooves 121 arranged in a matrix, and the rear end of the lifting shelf 13 is correspondingly arranged in the same sliding groove 121 at the same horizontal height, and a freely rotatable screw 18 is longitudinally penetrated in the sliding groove 121 in the same column, and the upper end of the screw 18 is placed on the top of the shelf mounting frame 12, and the lower end of the screw 18 longitudinally penetrates the sliding groove 121 in the same column in sequence and is threadedly connected to the rear end of the lifting shelf 13 in the sliding groove 121, and the upper end of the screw 18 is provided with a first bevel gear 16, and the top of the shelf mounting frame 12 is provided with a motor 15, and the power output of the motor 15 is connected to the second bevel gear 17 that can mesh and rotate with the first bevel gear 16.

[0043] The matrix of sliding slots 121 on the inner side of the shelf mounting bracket 12 not only provides stable horizontal guidance for the rear end of the lifting shelf 13, ensuring that the lifting shelf 13 in the same row always remains horizontal, but also reserves space for the installation of the lead screw 18 by distributing the same row, ensuring a regular component layout. The lead screw 18, which runs longitudinally through the same row of sliding slots 121, is threadedly connected to the rear end of the lifting shelf 13, forming the core of the transmission: the motor 15 drives the second bevel gear 17 to rotate, which, through engagement with the first bevel gear 16, drives the lead screw 18 to rotate. The threaded transmission converts the rotational motion into the vertical linear motion of the lifting shelf 13, allowing precise control of the lifting range.

[0044] Through the above-mentioned adjustment method, the lifting shelf 13 can flexibly press down the freeze-drying tray 3, so that the top of the freeze-drying tray 3 is close to the lifting shelf 13 and the bottom is close to the fixed shelf 14, solving the problem of uneven heat transfer caused by the traditional fixed shelf spacing, and further ensuring the drying efficiency and the consistency of the finished product quality.

[0045] As one of the preferred embodiments of the present invention, Figure 3 、 Figure 4 、 Figure 7 、 Figure 8 、 Figure 10 As shown, the tray rack 2 includes a sliding rack 21 and several groups of mounting base plates 23 symmetrically arranged on the left and right sides of the sliding rack 21 and corresponding to the position of the vacuum pipeline 5, a U-shaped tray mounting rack 22 correspondingly arranged above each group of mounting base plates 23, and a telescopic member 24 arranged between the mounting base plates 23 and the tray mounting rack 22. The top surface of the tray mounting rack 22 is symmetrically provided with mounting grooves 221, and the lower surface of the mounting side plate 32 of the freeze-drying tray 3 is provided with a sliding strip 321 that can cooperate with the sliding in the mounting groove 221. The rear side of the tray mounting rack 22 is provided with a magnetic fixing groove 222 that cooperates with the first magnetic strip 36, and the magnetic fixing groove 222 is provided with a second magnetic strip that can be magnetically attracted to the first magnetic strip 36.

[0046] Furthermore, in the above structure, the telescopic member 24 includes a lifting cylinder 241 and a first spring 242, and a limiting lifting groove 231 corresponding to the position of the telescopic member 24 is provided inside the mounting base 23, and the upper end of the lifting cylinder 241 is connected to the lower surface of the tray mounting frame 22, and the lower end of the lifting cylinder 241 is placed in the limiting lifting groove 231 and can slide in the limiting lifting groove 231, and the first spring 242 is arranged in the limiting lifting groove 231 and its two ends are respectively connected to the top inner wall of the lifting cylinder 241 and the bottom inner wall of the limiting lifting groove 231.

[0047] The structural design of the tray rack 2 balances ease of loading and unloading with drying stability. The various components work together to ensure precise positioning and flexible adjustment of the freeze-drying tray 3. The symmetrical mounting base 23 of the sliding rack 21 aligns with the position of the vacuum line 5, ensuring a precise path for subsequent water vapor extraction. The U-shaped tray mounting rack 22 accommodates the placement of the freeze-drying tray 3. Its top mounting groove 221 cooperates with the slide bar 321 of the freeze-drying tray 3 mounting side panel 32, enabling smooth sliding loading and unloading of the tray and reducing operational difficulty. The magnetic fixing groove 222 on the rear side of the tray mounting rack 22 and the second magnetic strip inside the tray mounting rack 22 magnetically secure the first magnetic strip 36 of the freeze-drying tray 3, preventing the tray from shifting during the drying process and ensuring uniform heating of the material and water vapor extraction.

[0048] The telescopic part 24 can realize fine adjustment of the freeze-drying tray 3 up and down. The upper end of the lifting cylinder 241 is connected to the tray mounting frame 22, and the lower end is limited to the limit lifting groove 231 of the mounting base 23 to ensure the stability of the lifting direction. The first spring 242 provides elastic support. When the lifting shelf 13 is pressed down, the tray mounting frame 22 squeezes the lifting cylinder 241 and compresses the first spring 242, driving the freeze-drying tray 3 to descend, so that its top is close to the lifting shelf 13 and the bottom is close to the fixed shelf 14, effectively improving the heat transfer efficiency.

[0049] As one of the preferred embodiments of the present invention, Figure 3 、 Figure 4 、 Figure 7 、 Figure 8 、 Figure 9 As shown, the lifting mechanism 4 includes an L-shaped plate 41 whose two ends are respectively connected to the mounting side plate 32 and the outer wall of the freeze-drying tray 3, a guide wheel 42 that passes through the inside of the side wall of the freeze-drying tray 3 and can rotate freely, a fixed pulley 44 arranged below the mounting side plate 32, a pressing column 45 that can be lifted and slid and is arranged inside the L-shaped plate 41, and a flexible rope 46 that transmits and connects the guide wheel 42 and the fixed pulley 44. The lower surface of the mounting side plate 32 is provided with a mounting frame 43, and the two ends of the fixed pulley 44 are rotatably mounted on the mounting frame 43.

[0050] Furthermore, in the above structure, a lifting limit slot 411 is provided inside the L-shaped plate 41, and the pressing column 45 can be lifted and lowered to pass through the mounting side plate 32, with the lower end placed in the lifting limit slot 411 and the upper end placed above the mounting side plate 32. The lower end of the pressing column 45 is connected to a sliding base 451 that can cooperate with the lifting limit slot 411 to limit sliding. The two ends of the flexible rope 46 are respectively connected to the sliding base 451 of the pressing column 45 and the edge position of the upper surface of the lifting hole plate 31. A second spring 47 is provided inside the lifting limit slot 411, and the two ends of the second spring 47 are respectively connected to the bottom of the sliding base 451 and the bottom of the lifting limit slot 411.

[0051] The structural design of the lifting mechanism 4 is centered around achieving flexible adjustment of the lifting orifice plate 31 within the freeze-drying tray 3. Each component works together to complete the lifting action, creating conditions for efficient water vapor discharge. The L-shaped plate 41 serves as a support frame, with its two ends connected to the mounting side plate 32 and the outer wall of the freeze-drying tray 3. The lifting limit slide 411 inside it provides a stable lifting guide for the press column 45 to prevent the press column from shifting. The press column 45 passes through the mounting side plate 32, and the sliding base 451 at the lower end cooperates with the lifting limit slide 411 to ensure vertical sliding; the second spring 47 provides a reset force for the press column 45 to ensure subsequent action cycles.

[0052] The guide wheel 42 and the fixed pulley 44 (fixed to the bottom of the mounting side plate 32 through the mounting bracket 43) jointly change the transmission direction of the flexible rope 46. When the lifting shelf 13 presses down the pressing column 45, the pressing column drives the sliding base 451 to move downward and compresses the second spring 47. The flexible rope 46 then pulls the lifting orifice plate 31 along the guide rod 34 to the middle of the freeze-drying tray 3, so that the sea buckthorn slices are placed on the upper and lower sides of the lifting orifice plate 31; after the lifting shelf 13 is raised, the second spring 47 is reset to push the pressing column to rise, the flexible rope 46 is relaxed, and the lifting orifice plate 31 falls back, making it convenient to take and place materials. This linkage design does not require additional power and relies on the equipment's own action to achieve orifice plate adjustment, effectively shortening the water vapor escape path and improving drying uniformity.

[0053] As one of the preferred embodiments of the present invention, Figures 5 to 8 As shown, the side wall of the freeze-drying tray 3 is penetrated by a plurality of through slots 35 distributed at equal intervals. A fixed base plate 33 is symmetrically provided at the bottom of the freeze-drying tray 3. Guide rods 34 are correspondingly provided at the four corners of the lifting orifice plate 31. The upper ends of the guide rods 34 are placed above the lifting orifice plate 31 and the lower ends are connected to the fixed base plate 33. The surface of the lifting orifice plate 31 is penetrated by vertical cylinders 312 distributed in a matrix. The lifting orifice plate 31 is penetrated by through holes 311 distributed in a matrix between adjacent vertical cylinders 312. The lower surface of the lifting shelf 13 is provided with a pipeline groove matching the vacuum pipeline 5. The vacuum pipeline 5 is arranged in the pipeline groove. The vacuum pipeline 5 includes a main pipe 51, and several long branch pipes 52 and short branch pipes 53 respectively connected to the main pipe 51. The long branch pipes 52 are arranged corresponding to the vertical cylinder 312. The inner diameter of the vertical cylinder 312 is larger than the outer diameter of the long branch pipes 52. The short branch pipes 53 are evenly arranged between adjacent long branch pipes 52.

[0054] The structural design of the freeze-drying tray 3 and the vacuum pipeline 5 focuses on the efficient discharge of water vapor and the uniformity of drying. The precise coordination of various components solves the problem of water vapor escape from traditional trays. The equidistant through-grooves 35 on the side wall of the freeze-drying tray 3 can assist in discharging water vapor from the edge of the tray, avoiding local water vapor accumulation and rehumidification; the symmetrical fixed base plate 33 at the bottom provides a stable support for the guide rod 34, and the guide rod 34 passes through the four corners of the lifting orifice plate 31, which can limit the lifting direction of the lifting orifice plate 31, ensuring that it always remains horizontal, avoiding deviation that affects material placement and water vapor extraction, and the vertical cylinder 312 is reserved for the long branch pipe 52 of the vacuum pipeline 5 to extend into the channel, and the through hole 311 facilitates the rapid circulation of water vapor above the lifting orifice plate 31, creating conditions for extraction.

[0055] The pipe groove on the lower surface of the lifting shelf 13 can fix the vacuum pipe 5 to prevent the pipe from shifting during the drying process. The main pipe 51 of the vacuum pipe 5 serves as the main channel, and the connected long branch pipe 52 corresponds to the vertical tube 312. The inner diameter of the vertical tube 312 is larger than the outer diameter of the long branch pipe 52, ensuring that the long branch pipe 52 can smoothly extend under the lifting orifice plate 31 to directly extract the water vapor below; the short branch pipe 53 between adjacent long branch pipes 52 is responsible for extracting water vapor above the lifting orifice plate 31, forming a synchronous upper and lower extraction path, greatly shortening the distance for water vapor to escape, reducing resistance, and effectively avoiding uneven local drying of the sea buckthorn slices, ensuring the consistency of the moisture content and crispness of the finished product.

[0056] The above description is only a preferred embodiment of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and modifications without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A production process for freeze-dried roxburghii tablets, characterized in that: The following steps are involved: S1. Select prickly pear with no pests and suitable maturity as raw material, wash the prickly pear, and then cut into 3-5mm prickly pear slices, remove the seeds and wash the prickly pear slices for the second time, and then dry the surface moisture; S2. Place the Rosa rugosa slices in 70-80°C hot water for 2-3 min, then remove the Rosa rugosa slices, air-dry the surface moisture, and immerse the blanched Rosa rugosa slices in the sugar solution for 1-2 h; S3. Place the roxburghii slices soaked in sugar solution in a freezer and pre-freeze at -30°C for 12 hours; S4. Place the pre-frozen roxburghii slices into a vacuum freeze dryer for vacuum freeze drying. After vacuum freeze drying is completed, freeze-dried roxburghii slices are obtained.

2. The production process of a roxburghii freeze-dried tablet according to claim 1, wherein In step S2, the solid-liquid ratio of the roxburghii slices to the sugar solution is 1:(1.5-2), the soaking temperature is 50-60°C, and the components of the sugar solution include: 20-30% maltooligosaccharide, 10-15% xylitol, 0.010-0.020% sucralose, and the balance is water.

3. The production process of a roxburghii freeze-dried tablet according to claim 1, wherein In step S4, the vacuum freeze-drying process is as follows: the pre-frozen roxburghii slices are placed in a vacuum freeze dryer and sequentially subjected to vacuum sublimation drying and vacuum analytical drying, the vacuum degree of the vacuum sublimation drying being 20-25 Pa, the temperature being 25-30 ° C, the moisture content of the vacuum sublimation dried roxburghii slices being 10 ± 2%, the vacuum degree of the vacuum analytical drying being 5-20 Pa, the temperature being 55-60 ° C, and the moisture content of the vacuum analytical dried roxburghii slices being 5 ± 2%.

4. The production process of a roxburghii freeze-dried tablet according to claim 1, wherein In step S4, the structure of the vacuum freeze dryer includes a vacuum freeze dryer body (1), a drying chamber (11) is provided inside the vacuum freeze dryer body (1), a shelf mounting frame (12) connected to the vacuum freeze dryer body (1) is provided inside the drying chamber (11), and a plurality of fixed shelves (14) are provided on the left and right inner surfaces of the shelf mounting frame (12) at equal distances along the height direction of the vacuum freeze dryer body (1), and a corresponding shelf (14) is provided above each of the fixed shelves (14) in parallel with the shelf mounting frame (12). A lifting shelf (13) is movable up and down on the side surface, and a tray rack (2) is respectively provided between the fixed shelves (14) on the left and right inner surfaces of the shelf mounting frame (12), the top of the tray rack (2) is slidably connected to the shelf mounting frame (12), and the bottom of the tray rack (2) is slidably connected to the vacuum freeze dryer body (1), and a plurality of freeze-drying trays (3) are provided on the tray rack (2), and the freeze-drying trays (3) are located between the lifting shelf (13) and the fixed shelf (14) and are equidistantly distributed along the length direction of the fixed shelf (14); The freeze-drying tray (3) is provided with a lifting hole plate (31) movably connected to the inner wall of the freeze-drying tray (3), and the left and right sides of the freeze-drying tray (3) are symmetrically provided with mounting side plates (32). Below the mounting side plates (32), there are provided a plurality of lifting mechanisms (4) connected to the outer wall of the freeze-drying tray (3) and the mounting side plates (32), respectively. The lifting mechanisms (4) are symmetrically provided on the left and right sides of the freeze-drying tray (3), and a first magnetic strip (36) is provided on the rear outer wall of the freeze-drying tray (3). The plurality of lifting mechanisms (4) are connected to the corresponding side of the lifting hole plate (31), and the lower surface of the lifting shelf (13) is provided with a vacuum pipeline (5) corresponding to the position of the freeze-drying tray (3).

5. The production process of a roxburghii freeze-dried tablet according to claim 4, characterized in that: The left and right inner surfaces of the shelf mounting frame (12) are provided with a plurality of sliding grooves (121) arranged in a matrix, and the rear end of the lifting shelf (13) is correspondingly arranged in the same sliding groove (121) at the same horizontal height, and a freely rotatable lead screw (18) is longitudinally penetrated in the sliding groove (121) in the same row, and the upper end of the lead screw (18) is placed on the top of the shelf mounting frame (12), and the lower end of the lead screw (18) longitudinally penetrates the sliding groove (121) in the same row in sequence and is threadedly connected to the rear end of the lifting shelf (13) in the sliding groove (121), and the upper end of the lead screw (18) is provided with a first bevel gear (16), and the top of the shelf mounting frame (12) is provided with a motor (15), and the power output of the motor (15) is connected to the second bevel gear (17) that can mesh with the first bevel gear (16) and rotate.

6. The production process of a roxburghii freeze-dried tablet according to claim 4, characterized in that: The tray rack (2) comprises a sliding rack (21) and a plurality of groups of mounting base plates (23) symmetrically arranged on the left and right sides of the sliding rack (21) and corresponding to the positions of the vacuum pipeline (5), a U-shaped tray mounting rack (22) correspondingly arranged above each group of mounting base plates (23), and a telescopic member (24) arranged between the mounting base plates (23) and the tray mounting rack (22), wherein the top surface of the tray mounting rack (22) is symmetrically provided with mounting grooves (221), the lower surface of the mounting side plate (32) of the freeze-drying tray (3) is provided with a sliding strip (321) capable of cooperating with the sliding in the mounting groove (221), the rear side of the tray mounting rack (22) is provided with a magnetic fixing groove (222) cooperating with the first magnetic strip (36), and the magnetic fixing groove (222) is provided with a second magnetic strip capable of magnetically attracting the first magnetic strip (36).

7. The production process of a roxburghii freeze-dried tablet according to claim 6, characterized in that: The telescopic member (24) includes a lifting cylinder (241) and a first spring (242). A limiting lifting groove (231) corresponding to the position of the telescopic member (24) is provided inside the mounting base (23). The upper end of the lifting cylinder (241) is connected to the lower surface of the tray mounting frame (22). The lower end of the lifting cylinder (241) is placed in the limiting lifting groove (231) and can slide in a limited position in the limiting lifting groove (231). The first spring (242) is provided in the limiting lifting groove (231) and its two ends are respectively connected to the top inner wall of the lifting cylinder (241) and the bottom inner wall of the limiting lifting groove (231).

8. The production process of a roxburghii freeze-dried tablet according to claim 4, characterized in that: The lifting mechanism (4) includes an L-shaped plate (41) whose two ends are respectively connected to the mounting side plate (32) and the outer wall of the freeze-drying tray (3), a guide wheel (42) that is arranged inside the side wall of the freeze-drying tray (3) and can rotate freely, a fixed pulley (44) arranged below the mounting side plate (32), a pressing column (45) that can be lifted and slid and is arranged inside the L-shaped plate (41), and a flexible rope (46) that transmits and connects the guide wheel (42) and the fixed pulley (44). The lower surface of the mounting side plate (32) is provided with a mounting frame (43), and the two ends of the fixed pulley (44) are rotatably mounted on the mounting frame (43).

9. The production process of a roxburghii freeze-dried tablet according to claim 8, characterized in that: A lifting limit slot (411) is provided inside the L-shaped plate (41), the pressing column (45) can be lifted and lowered to pass through the mounting side plate (32), and the lower end is placed in the lifting limit slot (411), and the upper end is placed above the mounting side plate (32), the lower end of the pressing column (45) is connected to a sliding base (451) that can cooperate with the lifting limit slot (411) to slide in a limited manner, the two ends of the flexible rope (46) are respectively connected to the sliding base (451) of the pressing column (45) and the edge position of the upper surface of the lifting hole plate (31), the lifting limit slot (411) is provided with a second spring (47), and the two ends of the second spring (47) are respectively connected to the bottom of the sliding base (451) and the bottom of the lifting limit slot (411).

10. The production process of a roxburghii freeze-dried tablet according to claim 9, characterized in that: The side wall of the freeze-drying tray (3) is provided with a plurality of through grooves (35) distributed at equal intervals, the bottom of the freeze-drying tray (3) is symmetrically provided with a fixed bottom plate (33), and the four corners of the lifting hole plate (31) are provided with corresponding guide rods (34), the upper end of the guide rod (34) is placed above the lifting hole plate (31), and the lower end is connected to the fixed bottom plate (33), the surface of the lifting hole plate (31) is provided with vertical cylinders (312) distributed in a matrix, and the lifting hole plate (31) is provided with through holes (311) distributed in a matrix between adjacent vertical cylinders (312); The lower surface of the lifting shelf (13) is provided with a pipeline groove matching the vacuum pipeline (5), and the vacuum pipeline (5) is arranged in the pipeline groove. The vacuum pipeline (5) includes a main pipe (51), a plurality of long branch pipes (52) and short branch pipes (53) respectively connected to the main pipe (51), and the long branch pipes (52) are arranged corresponding to the vertical cylinder (312). The inner diameter of the vertical cylinder (312) is larger than the outer diameter of the long branch pipes (52), and the short branch pipes (53) are evenly arranged between adjacent long branch pipes (52).

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