Fresh-cut fruit and vegetable anti-browning fine cutting and intensive pulse light treatment all-in-one machine and method

Abstract

The invention relates to the technical field of fruit and vegetable processing equipment, in particular to a fresh-cut fruit and vegetable anti-browning accurate cutting and intensive pulse light processing all-in-one machine and method integrating a series of processing links of raw material conveying, recognition and positioning, accurate cutting, waste treatment, enzyme activity inhibition, color protection and the like. The all-in-one machine integrates an automatic feeding and conveying device, a machine vision positioning unit, a variable-pitch cutting unit, a material stirring unit, a rotary slicing unit, a pulse intense light processing bin, a nano coating color protection unit and a PLC control system, continuous operation of fresh-cut fruits and vegetables from shape recognition, precise cutting and slicing to enzyme activity inhibition and color protection is achieved, the PLC control system is in linkage with all the modules, and the intelligent control of the fresh-cut fruits and vegetables is achieved. According to the characteristics of fruits and vegetables, segmentation parameters and pulse intense light parameters are dynamically adjusted, and an oxygen isolation protection layer is formed by combining a nano coating film. The problems of low cutting precision, difficulty in browning control, poor adaptability and the like in traditional processing are solved, and intelligent integrated equipment and technology are provided for deep processing of fruits and vegetables.

Description

Technical Field

[0001] This invention relates to the field of fruit and vegetable processing equipment technology, specifically to a processing equipment and method for preventing browning of fresh-cut fruits and vegetables that integrates a series of processing steps, from raw material transportation, identification and positioning, precise cutting, waste treatment to enzyme activity inhibition and color protection. Background Technology

[0002] Fresh-cut fruits and vegetables have become an important category in the food processing industry due to their convenience. However, during the cutting and processing, cell structure damage leads to the contact between polyphenol oxidase (PPO) and substrate, triggering an enzymatic browning reaction. This results in quality problems such as color deterioration, nutrient loss, and microbial contamination. In current industry practice, traditional processing technology systems have significant shortcomings: soaking in chemical color-protecting agents (such as sodium benzoate) easily leads to excessive residue levels; hot water blanching processes cause vitamin C loss rates exceeding 35%; and material transfer during segmented processing results in secondary contamination rates as high as 12%, severely hindering the high-quality development of the industry.

[0003] Existing manual or mechanical cutting equipment is difficult to adapt to the differentiated processing needs of fruits and vegetables of different shapes. It causes high damage to the end face tissue, which can easily aggravate the release of cell contents and the initiation of browning. Chemical color protection relies on reducing agents to inhibit enzyme activity. Although it can delay browning, there is a risk of additive residues such as sulfites. Although the hot water treatment process can reduce PPO activity to 20% of the initial level, it will lead to a significant decrease in the water-holding capacity of fruit and vegetable cells and softening of texture. More importantly, the cutting, enzyme inactivation and color protection processes are usually carried out independently, with long process connection time, which deepens the browning degree by 2-3 shades. The transfer of multiple equipment leads to a significant increase in the risk of microbial contamination and high energy consumption per unit of processing. For example, in the prior art, the peeling and dicing device disclosed in patent CN202323198427.0 only realizes the mechanical cutting function and does not integrate a module for preventing browning of sliced ​​fruits and vegetables; the pulsed light sterilization device in patent CN202323034974.5 lacks a synergistic mechanism for cutting precision control and coating preservation, and the lack of inactivation of polyphenol oxidase easily leads to obvious discoloration of products during storage; the chemical coating technology in patent CN202510504288.4 does not combine physical field inactivation of enzymes, and the color protection time is relatively short in fruits and vegetables with high PPO activity (such as fresh-cut pears).

[0004] In the field of fresh-cut fruit and vegetable processing, traditional processing technologies or existing patents generally face the problems of fresh-cut fruits and vegetables being prone to browning, rapid quality decline, and short shelf life. Moreover, the three steps of "cutting-enzyme inactivation-coating" are separated from each other, which directly leads to low processing efficiency, poor results, and high risk of secondary contamination. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a fresh-cut fruit and vegetable processing equipment that integrates precise cutting, pulsed light enzyme inactivation, and nano-coating for color protection, enabling efficient anti-browning treatment of fruits and vegetables with varying hardness, thereby improving nutrient retention and shelf life.

[0006] The technical solution is as follows: A machine integrating anti-browning precision cutting and pulsed high-intensity light treatment for fresh-cut fruits and vegetables, comprising the following units that work in sequence and in concert: The feeding unit includes a skirted conveyor belt, a cross partition, a drive motor, and a vibrating feeding plate, which are sequentially installed on the feeding unit frame. The skirts on both sides can prevent the material from slipping when it is conveyed at an incline. The skirted conveyor belt is provided with a cross partition in the middle to enhance friction and ensure stable material conveying. A drive motor is installed on one end face of the skirted conveyor belt, and the side of that end is a vibrating feeding plate. A machine vision positioning unit, comprising a conveying module and a vision acquisition module sequentially mounted on a vision unit frame 23; The conveying module includes an anti-slip conveyor belt, a servo motor A, and conveyor belt side plates. Conveyor belt side plates are installed on both sides of the anti-slip conveyor belt in the conveying direction. The servo motor A is installed below the anti-slip conveyor belt, and its output end is connected to the anti-slip conveyor belt drive end via a belt. The visual acquisition module includes a light-shielding box, a through-beam infrared sensor, a surface light source, a TOF sensor, and a CCD camera. The surface light source, TOF sensor, and CCD camera are all installed on the top of the light-shielding box, while the through-beam infrared sensor is installed on the side plate of the conveyor belt. The inner wall of the light-shielding box is lined with reflective material to enhance the utilization rate of the light source. Two surface light sources are suspended on the top of the light-shielding box, and the surface light sources are synchronously controlled with the camera. The CCD camera and ToF sensor are integrated on the top of the light-shielding box through a bracket. The optical axis is perpendicular to the conveyor belt. An anti-slip belt conveyor is installed directly below the light-shielding box to transport materials through the detection area. The anti-slip belt conveyor is driven by a servo motor and synchronously controlled with the trigger signal of the CCD camera. A through-beam infrared sensor is installed on the side plate of the conveyor belt of the anti-slip belt conveyor to detect the position of the material and send a signal to the industrial control computer to light up the light source and trigger the CCD camera to take a picture. The cutting unit includes, in sequence, a variable-pitch cutting unit, a feeding unit, and a rotary cutting unit. The variable-pitch cutting unit is located on the conveying path after the light-shielding box. The variable-pitch cutting unit includes a servo motor B, a ball linear guide, a slider, a positioning rod, a variable-pitch guide groove, and a cutter. The cutter is a parallel cam plate groove type blade, which is fixed directly below the slider. The slider moves linearly on the ball linear guide. The positioning rod on the side of the slider is connected to the variable-pitch guide groove. The variable-pitch guide groove can be replaced according to the characteristics of fruits and vegetables to adapt to different spacing of parallel blades. The cutter is driven by the servo motor B. When the push rod of the servo motor B moves downward to push the ball linear guide, due to the restriction of the positioning rod and the variable-pitch guide groove, the slider drives the cutter to move left and right synchronously until the positioning rod reaches the bottom of the variable-pitch guide groove, so that the cutters are arranged in parallel and the spacing is equal to the spacing at the end of the variable-pitch guide groove. The material feeding unit includes an infrared sensor, a sorting trough, and a material feeding cylinder. The infrared sensor detects the material position and sends a signal to the material feeding cylinder. The material feeding cylinder is fixed above the anti-slip conveyor belt and is used to apply lateral displacement to the head and tail waste of the cut fruit and vegetables. The waste is collected through the lateral sorting trough, while the middle section of the material enters the next process. The rotary slicing unit includes a rotary cutter controlled by a servo motor C. The rotary cutter is installed inside the cutter housing. For fruits and vegetables with high hardness, the head and tail waste can be cut and separated first by the variable pitch cutting unit, and the middle section of material can be sliced ​​by the rotary cutter. The pulsed high-intensity light processing unit includes, in sequence, a silicone paddle, a heat-resistant conveyor belt, a pulsed high-intensity light processing chamber, and a heat-resistant belt drive motor. The silicone paddle and the heat-resistant belt drive motor are respectively installed on the output and output sides of the heat-resistant conveyor belt. The chamber contains pulse light sources and fruits and vegetables. The pulse light source is driven by a pulse light generator and is located directly above the light source inside the chamber. The light source is located directly above the heat-resistant conveyor belt. The fruits and vegetables pass through the chamber at a constant speed by a high-temperature resistant belt conveyor. The heat-resistant conveyor belt is driven by a servo motor to achieve synchronous control of speed and light source triggering, ensuring that each material receives at least 5 pulse irradiations. The chamber is equipped with a nitrogen circulation system, which is filled with high-purity nitrogen. The nano-coating color protection unit is located downstream of the pulsed intense light treatment chamber. Fruits and vegetables are conveyed at a constant speed through the spraying unit by the conveying roller. The spraying unit includes a sealed spraying chamber, a coating liquid recovery tank, and a conveying roller. The coating liquid recovery tank is located below the spraying chamber, and the conveying roller is located at the discharge end of the spraying chamber. Spraying chamber baffles are provided on both sides of the spraying chamber. An atomizing sprayer is provided above the spraying chamber to atomize the coating liquid into tiny droplets. The flow rate of the coating liquid is controlled by the liquid supply unit. A coating liquid recovery tank is provided at the bottom of the spraying chamber to collect the coating liquid that has not adhered. The all-in-one machine is also equipped with a PLC control system, which is installed on the industrial computer. The PLC control system is connected to the drive motor, vibrating feeding tray, conveying module, vision acquisition module, variable pitch cutting unit, material feeding unit, rotary slicing unit, pulsed light generator and nano-coating color protection unit via electrical signals. The PLC control system is used to receive the sensor signals of each unit, coordinate and control the actions of each unit, and adjust the cutting parameters (such as blade spacing and speed) and process parameters such as pulsed light and coating in real time according to the material characteristics, so as to realize the linkage and coordination of each link.

[0007] Furthermore, after the feeding unit conveys the fruits and vegetables to the machine vision positioning area of ​​the light-shielding box, the through-beam infrared sensor triggers the CCD camera to work synchronously with the light source to acquire the RGB morphological image of the fruits and vegetables. At the same time, the TOF sensor synchronously acquires a three-dimensional point cloud model. Based on the RGB image, a pre-trained deep learning segmentation model (including but not limited to target detection models with instance segmentation capabilities such as YOLOv8 nano and YOLOv5) is called to perform semantic segmentation, identify the outer contour boundary of the fruits and vegetables and extract contour feature parameters. Based on the above three-dimensional point cloud model, the spatial coordinate points at both ends of the fruits and vegetables are determined by point cloud registration, and the spatial distance is calculated and converted into actual fruit diameter parameters. Then, the contour feature parameters and fruit diameter parameters are combined, and the cutting node position is determined by a preset geometric algorithm. Finally, the contour feature parameters, fruit diameter parameters and cutting node marker data are aligned with the coordinate system and timestamp to form a complete positioning information dataset and output to the PLC control system. Furthermore, the adjustable-pitch cutter includes one or more sets of parallel cutter units, each containing 1-7 blades. The number of blades is dynamically adjusted according to the length and hardness parameters of fruits and vegetables in the positioning information dataset. When the hardness of the fruits and vegetables exceeds a preset threshold, the first cutting mode is activated, in which a single-blade cutter unit is used to cut off the head and tail of the fruits and vegetables and then conveys them to the rotary cutting unit. When the hardness of the fruits and vegetables is lower than the preset threshold, the second cutting mode is activated, in which a multi-blade cutter unit (blade number ≥ 2) is used to continuously slice the fruits and vegetables through repeated motion. The slice thickness of the cutter group is equidistant from the distance between the ends of the variable-pitch guide groove. The distance between the ends of the variable-pitch guide groove can be adjusted within the range of 2-10 mm through replaceable guide grooves. Different specifications of guide grooves correspond to different preset slice thickness values. The blade number adjustment, cutting mode selection, and variable-pitch guide groove configuration are all linked to the positioning information dataset. The cutting parameters are automatically configured according to the material length, hardness parameters, and cutting node markers contained in the dataset. Furthermore, the rotary slicing unit uses a servo motor C as its core drive. By receiving pulse control signals from the PLC, it adjusts the rotation speed and start / stop timing, thereby driving the cutter to rotate and perform slicing processing on high-hardness fruits and vegetables (such as carrots and sweet potatoes). The rotation speed of the servo motor C and the rotation angle of the cutter are dynamically adapted according to the material contour parameters and slicing thickness requirements in the positioning information dataset to ensure slicing accuracy and surface flatness. Furthermore, the cutting process is equipped with modular cutters for fruits and vegetables with different hardness levels. The adjustable spacing cutter is suitable for fruits and vegetables with a hardness of <3 kg / cm² (such as fruits, vegetables, and scallions), while the rotary cutter is suitable for fruits and vegetables with a hardness of >3 kg / cm² (such as carrots). Furthermore, the slicing process obtains the hardness parameters of fruits and vegetables through the positioning information dataset and compares them with the preset threshold of 3 kg / cm². When the material hardness is detected to be <3 kg / cm², the adjustable spacing cutter is automatically called to slice fruits and vegetables, such as scallions, and other crisp fruits and vegetables. When the material hardness is detected to be >3 kg / cm², the rotary cutter unit is automatically called to slice carrots, sweet potatoes, and other high-fiber fruits and vegetables. The switching of different cutter groups is automatically executed by the PLC control system, and this switching process is linked with the adjustment of the end spacing of the variable pitch guide groove and the configuration of the parameters of each servo motor to ensure the matching of the slice thickness with the characteristics of the fruits and vegetables. Furthermore, the pulsed light emitter and nitrogen environment control of the pulsed light treatment chamber follow the following parameter configuration and linkage logic: the single pulse energy density of the pulsed light emitter is set to 1~10 J / cm², the irradiation distance between it and the surface of fresh-cut fruits and vegetables can be adjusted within the range of 5~20 cm, and the number of pulsed light treatments is 1~5 times. The wavelength of the pulsed light is 200-400 nm, the pulse width is 50-200 μs, the single irradiation time is 100-500 ms, and the irradiation interval is 0.5-2 s. At the same time, the chamber is filled with nitrogen gas with a purity of ≥99.9% through the gas circulation system, the nitrogen flow rate is 10-20 L / min, the oxygen sensor detects the oxygen content in the chamber in real time and feeds it back to the gas circulation system, and the oxygen concentration in the chamber is maintained <0.5% by dynamically adjusting the nitrogen flow rate. The above pulsed light parameters are adaptively adjusted according to the characteristics of fruits and vegetables (such as surface area and hardness) and the cutting parameters of the blade group in the positioning information dataset to ensure the polyphenol oxidase inhibition effect. Furthermore, the structure and parameter configuration of the nano-coating color protection unit are as follows: the coating liquid is a mixed solution of 0.5-2wt% chitosan solution and 0.1-0.5wt% nanocellulose; the atomizing nozzles of the atomizing sprayer are arranged in a 4×2 matrix with a nozzle diameter of 0.5 mm and an atomization pressure of 0.1-0.5 MPa to ensure that the atomized droplet size is ≤50 μm, thereby forming an antioxidant and antibacterial coating on the surface of fruits and vegetables; the liquid supply unit is a peristaltic pump with a flow rate of 3-10 mL / min, and the flow rate can be dynamically adjusted according to the material surface area parameters in the positioning information dataset to ensure coating uniformity and economy; Furthermore, the pulsed intense light trigger frequency is matched in real time with the servo-driven slicing speed to ensure that the flatness of the slice end face is ≤0.2mm, thereby effectively reducing tissue damage after fruit and vegetable slicing and avoiding accelerated browning. At the same time, the industrial bus receives real-time three-dimensional coordinate data of fruits and vegetables from the machine vision positioning unit system, feedback signals of blade spacing from the adjustable spacing slicing unit, action signals from the feeding cylinder, rotation speed data of the rotary slicing unit, and irradiation intensity signals from the pulsed intense light treatment chamber. Based on the above signals, the slicing thickness, pulse energy density, and coating liquid flow rate are dynamically optimized to achieve integrated linkage control of "identification-slicing-enzyme inactivation-color protection". In addition, the energy density, light source distance, and number of treatments of the pulsed intense light are adjusted according to the fruit and vegetable variety, the number of slices, and the surface area, while the ratio and flow rate of the coating liquid are matched and controlled to ensure that the long-term inhibition rate of polyphenol oxidase is ≥80% and to avoid deepening of browning.

[0008] The technical solution provided by this invention has the following advantages compared with the prior art: (1) Precise cutting reduces browning inducing factors. A dual vision positioning system composed of a CCD camera and a ToF sensor is adopted. Combined with the dual blade group of variable distance cutting unit and rotary cutting unit for coordinated control, the cutting parameters can be dynamically adjusted for materials with different shapes (such as fruits and vegetables with curvature ≥15°) and hardness, which significantly reduces cell structure damage, reduces the probability of polyphenol oxidase (PPO) contacting the substrate, and inhibits the browning initiation rate from the source, solving the problem of accelerated browning caused by insufficient precision of traditional cutting equipment.

[0009] (2) Multi-level anti-browning mechanism enhances color protection effect. The innovative synergistic anti-browning system of "pulsed strong light inactivating enzyme + nano-coating to isolate oxygen" is adopted: pulsed strong light directly inhibits PPO activity through physical field action (inhibition rate ≥80%), avoiding the residual risk of traditional chemical color protectants (such as sulfites). Subsequently, the nano-coating forms a dense barrier on the slice surface, isolating oxygen from contact with the enzyme reaction system, further delaying browning. The synergistic effect of the two makes the browning index ΔE of fresh-cut fruits and vegetables ≤3.0, which is significantly improved compared with traditional processes, and completely eliminates the hidden danger of chemical agent residues.

[0010] (3) Quantitative improvement in nutrient retention and shelf life extension: The short-term and efficient treatment with pulsed light avoids the loss of vitamin C caused by traditional hot water blanching. Combined with the antioxidant protection of the coating, the retention rate of vitamin C and polyphenols is ≥70% within 7 days. At the same time, the low-oxygen environment and antibacterial coating work together to inhibit the growth of microorganisms. Under 4℃ conditions, the shelf life is extended by 3 to 5 days compared with the traditional segmented processing, which solves the industry pain point of "rapid deterioration of quality and short shelf life" of fresh-cut fruits and vegetables.

[0011] (4) Continuous integration reduces processing costs. The integrated equipment integrates the processes of "feeding-positioning-cutting-enzyme inactivation-color protection". The PLC control system realizes dynamic linkage of parameters (such as real-time matching of cutting speed and pulse frequency). Continuous operation reduces secondary pollution during the transfer of fruits and vegetables, and energy consumption is more dispersed and reduced, significantly improving the economic benefits of the industry.

[0012] (5) Systematic innovation in technology integration: For the first time, machine vision adaptive cutting, pulsed light physical enzyme inactivation, and nano green coating are integrated through modular design and intelligent control, breaking through the limitations of existing equipment with single function and insufficient synergy. Through dynamic optimization of parameters (such as adjusting the coating flow rate according to the material surface area and switching the cutting blade group according to the hardness), the universal processing of multiple varieties of fruits and vegetables is realized, providing a systematic solution for intelligent processing of fresh-cut fruits and vegetables.

[0013] (6) This patent innovatively proposes to develop an intelligent equipment and process that integrates visually guided precise cutting, pulsed strong light enzyme inactivation, and natural coating liquid synergistic curing. It integrates the advantages of the patented technology in the background technology into the integrated system, fundamentally solves the problem of process separation, and significantly slows down the browning rate of fresh-cut fruits and vegetables. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a schematic diagram of the overall structure of the all-in-one machine according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the machine vision positioning unit structure according to an embodiment of the present invention; Figure 3 This is a detailed structural diagram of the variable-pitch segmentation unit and the rotational segmentation unit according to an embodiment of the present invention; Figure 4 This is a structural diagram of the internal structure of the pulsed high-intensity light processing chamber according to an embodiment of the present invention; Figure 5This is a schematic diagram of the nano-coating color-protecting unit structure in an embodiment of the present invention.

[0015] The labels in the diagram represent: 11. Skirted conveyor belt; 12. Horizontal partition; 13. Drive motor; 14. Vibrating feeder; 15. Feeding unit frame; 21. Conveying module; 211. Anti-slip conveyor belt; 212. Servo motor A; 213. Conveyor belt side plate; 22. Vision acquisition module; 221. Light-shielding box; 222. Through-beam infrared sensor; 223. Surface light source; 224. TOF sensor; 225. CCD camera; 23. Vision unit frame; 31. Variable pitch cutting unit; 311. Servo motor B; 312. Positioning rod; 313. Ball linear guide; 314. Slider; 315. Cutter; 316. Variable pitch 32. Guide chute; 32. Feeding unit; 321. Infrared sensor; 322. Separating chute; 323. Feeding cylinder; 33. Rotary cutting unit; 331. Servo motor C; 332. Rotary cutter; 333. Cutter housing; 41. Silicone shim; 42. Heat-resistant conveyor belt; 43. Pulse intense light treatment chamber; 431. Chamber body; 432. Pulse intense light emitter; 433. Oxygen sensor; 434. Pulse intense light source; 435. Nitrogen circulation system; 44. Heat-resistant belt drive motor; 51. Spray chamber; 511. Spray chamber baffle; 512. Liquid supply unit; 513. Atomizing sprayer; 52. Coating liquid recovery tank; 53. Conveying roller. Detailed Implementation

[0016] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0017] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0018] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0019] Example 1: Preliminary experiments determined that when the energy density of the pulsed intense light is <1 J / cm², the PPO inhibition rate is ≤60%; when the energy density is >10 J / cm², the surface burn rate of fruits and vegetables is ≥10%.

[0020] The specific implementation steps of the anti-browning precision cutting and pulsed intense light synergistic treatment process for medium-hardness fruits and vegetables (cucumbers) are as follows: 1. Raw material pretreatment: Select fresh cucumbers (variety: densely prickly cucumber, length 20~25 cm, diameter 3~4 cm, firmness 2.5~2.8 kg / cm²), remove surface dirt and damaged parts, rinse with clean water and drain to ensure that there is no free water on the surface.

[0021] 2. Automatic feeding and vision positioning: (1) Feeding control: The pre-treated cucumbers enter the skirt belt conveyor (width 15 cm, skirt height 5 cm, cross plate spacing 10 cm), the conveying speed is set to 0.5 m / s, driven by the drive motor 13 (power 0.75 kW, speed 500 r / min), the cross plate 12 and the anti-slip skirt conveyor belt 11 (surface friction coefficient 0.8) work together to prevent the cucumbers from rolling, and then the cucumbers are oriented and sorted by the vibrating feeding plate 14 (model: ZDP-300, vibration frequency 50 Hz) to ensure that the stem faces forward or backward; (2) Dual vision detection trigger: When the cucumber enters the light-shielding box 221 (size 80 cm×50 cm×50 cm, with aluminum reflective film on the inner wall) of the machine vision positioning unit along the anti-slip conveyor belt 211, the side-mounted infrared sensor 222 is blocked, and a signal is sent to the industrial control computer, which simultaneously triggers the surface light source 223 (power 30 W, color temperature 6500 K) to light up and the CCD camera 225 (resolution 720×720, frame rate 60 FPS) to take pictures. The trigger delay is ≤10 ms. (3) Data acquisition and processing: CCD camera 225 acquires RGB images and transmits them to industrial control computer via Ethernet. The pre-trained YOLOv8 Nano model (trained with about 2000 fruit and vegetable images, mAP@0.5=0.92) is called to perform instance segmentation. The contour extraction is completed within 200 ms (error ≤0.5 mm). The head (stem) and tail cutting baseline are marked. TOF sensor 224 synchronously acquires three-dimensional point cloud. The ICP algorithm is used for registration. The spatial distance (fruit diameter) between the two ends of the cucumber is calculated. The central axis is fitted by least squares method in combination with the contour data. Three equally divided cutting planes are automatically generated for cucumbers with a curvature ≥15° (ensuring end face flatness ≥92%). The positioning information dataset (including contour parameters, fruit diameter, and cutting coordinates) is sent to PLC via bus after coordinate transformation (aligned with the coordinate system of the cutting unit).

[0022] 3. Variable-pitch cutting and waste treatment (1) Knife assembly parameter configuration: The PLC determines the cucumber hardness (2.5~2.8 kg / cm²<3 kg / cm²) based on the positioning data, calls the variable pitch cutting unit 31, automatically selects 7 cam plate groove type cutters (blade thickness 0.1 mm), drives the slider 314 to move along the ball linear guide rail 313 through the servo motor B311, sets the end spacing of the variable pitch guide groove 316 to 10 mm (corresponding to the cutter spacing and slice thickness of 10 mm), and triggers the limit to complete the calibration when it reaches the bottom of the variable pitch guide groove 316. The whole process takes ≤200ms. (2) Cutting execution: The cucumber enters the cutting area with the conveyor belt. The servo motor B311 receives the PLC pulse signal (frequency 500 Hz) and drives the 315 cutter group to move downward at a speed of 50 mm / s. The first blade is aligned with the head cutting line (removing 10 mm of the stem). The cutting pressure is set to 50 N (feedback in real time through the pressure sensor). After cutting, the conveyor belt moves forward 70 mm (total coverage length of the cutter group). The cutter group repeats the cutting action until 3 cuts are completed. The cutting cycle of a single cucumber is 1.2 s. (3) Waste separation: After being cut, the cucumbers enter the feeding unit 32 along the conveyor belt (speed 0.5 m / s). When the infrared sensor 321 detects waste (cucumber head / tail), it sends a signal to the PLC, which drives the feeding cylinder 323 to extend within 100 ms and push the waste to the side feeding groove 322. The qualified slices continue to be conveyed to the next process.

[0023] 4. Pulsed intense light inactivation treatment (1) Material sorting: qualified slices are sorted into single layers by silicone squeegees 41 to avoid overlapping and obstruction, and then enter the pulse intense light treatment chamber 43 (volume 0.5 m³, inner wall made of 304 stainless steel, surface matte treatment to reduce reflection interference) via heat-resistant conveyor belt 42 (material: PTFE, width 25 cm). The conveying speed is controlled by a servo motor (model: MSMD042G1U, speed 300 r / min). (2) Parameter linkage control: The PLC calculates the pulse intensity light trigger frequency based on the slice thickness (10 mm) and conveying speed (0.5 m / s): f = v×n / 60 = (0.5×1000 mm / s ÷ 10 mm / s)×3 times / 60=2.5 ​​Hz, and sends a trigger signal to the pulse intensity light transmitter 432, where v is the slicing rate (slices / minute) and n is the number of pulses processed in a single operation; (3) Intense light treatment: A pulsed intense light source 434 (wavelength 200~400 nm, main wavelength 254 nm) was installed at the top of the chamber 431 (10 cm away from the slice surface). The single pulse energy density was 5 J / cm², the pulse width was 100 μs, the single irradiation time was 200 ms, the interval was 1 s, and a total of 3 treatments were performed, with a cumulative irradiation energy of 15 J / cm². The nitrogen circulation system 435 (including a scroll compressor, flow rate 10 L / min) in the chamber 431 was continuously filled with 99.99% high-purity nitrogen. The oxygen sensor 433 detected the oxygen concentration in real time. When the concentration was >0.5%, the PLC controlled the solenoid valve to increase the nitrogen flow rate to 15 L / min to ensure that the oxygen concentration was <0.5% throughout the treatment. After treatment, the PPO activity was detected (using the catechol colorimetric method), and the inhibition rate was 88.43%. There was no burn on the slice surface.

[0024] 5. Nano-coating for color protection (1) Preparation of coating solution: 1 wt% chitosan (molecular weight 10000 Da, degree of deacetylation 90%) and 0.5 wt% nanocellulose (length about 500 nm, diameter about 20 nm) mixed solution was used. After magnetic stirring, it was filtered through a 0.22 μm filter membrane and stored in a constant temperature storage tank at 4 ℃. (2) Spraying parameter control: The PLC controls the flow rate of the peristaltic pump (model: BT100-2J) to 8 mL / min based on the surface area of ​​the slice (the area of ​​a single slice is about 6~9 cm²). The coating liquid is delivered to the atomizing nozzle (4×2 matrix arrangement, nozzle diameter 0.5 mm) of the atomizing sprayer 513 through the liquid supply pipe (inner diameter 4 mm). Compressed air (0.3 MPa) is used to stabilize the pressure through the pressure reducing valve, so that the droplets are atomized into tiny particles. (3) Coating and recycling: The slices enter the sealed spray chamber 51 (volume 0.3 m³), ​​and pass through the spraying area under the drive of the conveying roller 53 (rotation speed 30 rpm, surface covered with silicone anti-slip layer). The atomized droplets are evenly attached to the surface of the slices. The unattached coating liquid is collected by the bottom coating liquid recycling tank 52, filtered by the filter screen and recycled.

[0025] 6. Finished product inspection The processed cucumber slices were stored at 4 ℃ and tested at 0, 3, 7 and 12 days. Table 1 shows the quality test results of cucumbers treated by the present invention compared with those processed by traditional methods. The browning index was determined by a CR-400 colorimeter, vitamin C was determined by 2,6-dichlorophenolindophenol titration, and the total phenol retention rate was determined by the Folin-phenol method.

[0026] Based on the cucumber test data in Table 1, this invention is significantly effective in delaying browning and extending shelf life: The browning index (ΔE) increased gradually, from 0.35 on Day 0 to 3.12 on Day 12, an increase of 2.77 over 12 days. In contrast, the ΔE of the mechanical cutting + citric acid soaking group increased from 0.31 to 5.17 (an increase of 4.86), and the ΔE of the cryogenic color protection group increased from 0.29 to 3.38 (an increase of 3.09). In particular, on Day 7, the ΔE of this invention (2.30) was 52.3% lower than that of the mechanical cutting + citric acid soaking group (4.82) and 7.0% lower than that of the cryogenic color protection group (2.47). Regarding nutrient retention, the total phenol retention rate of this invention was 63.73% on Day 12, which was 1.27 times that of the mechanical cutting + citric acid soaking group (50.14%) and 1.04 times that of the frozen color protection group (61.22%). The vitamin C retention rate of this invention was 60.83% on Day 12, which was 1.26 times that of the mechanical cutting + citric acid soaking group (48.39%) and 14.4% higher than the frozen color protection group (53.16%). With ΔE ≤ 3.0 as the acceptable threshold for the product, the shelf life of cucumbers treated by this invention can be extended to 12 days at 4 ℃ (ΔE = 3.12 on Day 12, close to the threshold), which is at least 5 days longer than the mechanical cutting + citric acid soaking process (ΔE = 4.82 on Day 7, which exceeded the standard) and 2-3 days longer than the frozen color protection process. This fully demonstrates that this invention can effectively delay browning and extend the shelf life of the product.

[0027] Table 1 Comparison of cucumbers treated by the present invention with those treated by traditional methods.

[0028] Example 2: A process for preventing browning in high-hardness fruits and vegetables (carrots) through precision cutting and synergistic treatment with pulsed intense light. The specific implementation steps are as follows: 1. Raw material pretreatment Select fresh carrots (variety: Hongying No. 2, length 15~20 cm, diameter 4~6 cm, hardness 4~5 kg / cm²), remove surface dirt and sand with a brush washing machine, manually remove damaged and deformed individuals, drain and set aside.

[0029] 2. Automatic feeding and vision positioning: (1) Feeding control: The pre-treated carrots enter the skirt belt conveyor (width 15 cm, skirt height 5 cm, cross plate spacing 10 cm), the conveying speed is set to 0.5 m / s, driven by the drive motor 13, the cross plate 12 and the anti-slip skirt conveyor belt 11 work together to prevent the carrots from rolling, and then the vibrating feeding plate 14 is used to orient and sort them to ensure that the stem faces forward or backward; (2) Dual vision detection trigger: When the carrot enters the light-shielding box 221 (size 80 cm×50 cm×50 cm, with aluminum reflective film on the inner wall) of the machine vision positioning unit along the anti-slip conveyor belt 211, the side-mounted infrared sensor 222 is blocked and sends a signal to the industrial control computer, which simultaneously triggers the surface light source 223 to light up and the CCD camera 225 (resolution 720×720, frame rate 60FPS) to take pictures. The trigger delay is ≤10 ms.

[0030] (3) Data acquisition and processing: CCD camera 225 acquires RGB images and transmits them to the industrial control computer via Ethernet. The pre-trained YOLOv8 Nano model (trained with about 3,000 images of root and stem fruits and vegetables, mAP@0.5=0.93) is called to perform instance segmentation, and the head (stem) and tail segmentation baselines are marked. TOF sensor 224 synchronously acquires three-dimensional point clouds, registers them through ICP algorithm, calculates the spatial distance (fruit diameter) between the two ends of the cucumber, and fits the central axis by least squares method in combination with the contour data. For carrots with a curvature ≥10°, two equally divided segmentation planes are automatically generated. The positioning information dataset (including contour parameters, fruit diameter 35~45mm, segmentation coordinates) is sent to the PLC via bus after coordinate transformation (aligned with the coordinate system of the segmentation unit).

[0031] 3. Variable-distance slitting, waste disposal, and rotary slicing (1) Knife assembly parameter configuration: The PLC determines the carrot hardness (4~5 kg / cm²>3 kg / cm²) based on the positioning data. It first starts the variable pitch cutting unit 31 to remove the head and tail waste, and automatically selects a cam plate groove type cutter (blade thickness 0.15mm). The cutter 315 is fixed to the middle slider 314. The positioning rod 312 connected to the cutter 315 forms a matching constraint with the vertically arranged variable pitch guide groove 316, allowing the cutter 315 to complete the vertical cutting action without any lateral displacement. The cutter 315 is driven to move vertically by the servo motor B311. When it reaches the bottom of the variable pitch guide groove 316, the limit is triggered to complete the calibration. (2) Head and tail removal: When the carrot enters the cutting area, the servo motor B311 receives the PLC pulse signal and drives the cutter group 315 to move downward at a speed of 40 mm / s. According to the marked head and tail cutting lines, the top 5 mm of the head and the root 5 mm of the tail are cut off respectively. The cutting pressure is set to 80 N. After cutting, the conveyor belt moves forward. (3) After the head and tail are cut, the carrots enter the feeding unit 32 along the conveyor belt (speed 0.5 m / s). When the infrared sensor 321 detects waste (carrot head / tail), it sends a signal to the PLC, which drives the feeding cylinder 323 to extend within 100 ms and pushes the waste to the side feeding trough 322. The middle section of material continues to be conveyed to the next process. (4) Rotary slicing: The middle section of carrot (12~20 cm in length) is fed to the rotary slicing unit 33. The PLC sends a signal to the servo motor C331. According to the requirement of 3 mm slice thickness, the speed is set to 1000 r / min. The rotary cutter 332 is driven by the coupling. The slice thickness is 3 mm. The slicing cycle of a single carrot is about 2.5 s.

[0032] 4. Pulsed intense light inactivation treatment (1) Material sorting: qualified slices are sorted into single layers by silicone picks 41 to avoid overlapping and obstruction, and enter the pulse intense light treatment chamber 43 through the heat-resistant conveyor belt 42. The conveying speed is controlled by a servo motor. (2) Parameter linkage control: The PLC calculates the pulse intensity light trigger frequency based on the slice thickness (3 mm) and conveying speed (0.3 m / s): f = v×n / 60 = (0.3×1000 mm / s ÷ 3 mm / s)×3 times / 60 = 8.3 Hz, and sends a trigger signal to the pulse intensity light transmitter 432, where v is the slicing rate (slices / minute) and n is the number of pulses processed in a single operation; (3) Intense light treatment: A pulsed intense light source 434 (wavelength 200~400 nm, main wavelength 254 nm) was installed at the top of the chamber 431 (20 cm away from the slice surface). The single pulse energy density was 10 J / cm², the pulse width was 200 μs, the single irradiation time was 500 ms, the interval was 2 s, and a total of 5 treatments were performed, with a cumulative irradiation energy of 50 J / cm². The nitrogen circulation system 435 (including a scroll compressor, flow rate 10 L / min) in the chamber 431 continuously filled it with high-purity nitrogen. The oxygen sensor 433 detected the oxygen concentration in real time. When the concentration was >0.5%, the PLC controlled the solenoid valve to increase the nitrogen flow rate to 20 L / min to ensure that the oxygen concentration was <0.5% throughout the treatment. After treatment, the PPO activity was detected (using the catechol colorimetric method), and the inhibition rate was 91.37%. There was no burn on the slice surface.

[0033] 5. Nano-coating for color protection (1) Preparation of coating solution: 2 wt% chitosan (molecular weight 10000 Da, degree of deacetylation 90%) and 0.1 wt% nanocellulose (length about 500 nm, diameter about 20 nm) mixed solution were used. After magnetic stirring, the solution was filtered through a 0.22 μm filter membrane and stored in a constant temperature storage tank at 4 ℃. (2) Spraying parameter control: The PLC controls the flow rate of the peristaltic pump to 10 mL / min based on the surface area of ​​the slice (the area of ​​a single slice is about 5~12 cm²), and delivers the coating liquid to the atomizing nozzle (4×2 matrix arrangement, nozzle diameter 0.5 mm) of the atomizing sprayer 513 through the liquid supply pipe (inner diameter 4 mm). Compressed air (0.5 MPa) stabilizes the pressure through the pressure reducing valve, so that the droplets are atomized into tiny particles; (3) Coating and recycling: The slices enter the sealed spray chamber 51 (volume 0.3 m³), ​​and pass through the spraying area under the drive of the conveying roller 53 (rotation speed 30 rpm, surface covered with silicone anti-slip layer). The atomized droplets are evenly attached to the surface of the slices. The unattached coating liquid is collected by the bottom coating liquid recycling tank 52, filtered by the filter screen and recycled.

[0034] 6. Finished product inspection The processed carrot slices were stored at 4 ℃ and tested at 0, 3, 7, and 12 days. Table 2 shows the quality test results of carrots treated according to this invention compared with those processed using traditional methods. The browning index was determined using a CR-400 colorimeter; the vitamin C content was determined using the 2,6-dichlorophenolindophenol titration method; and the carotene content was determined using HPLC (GB 5009.83).

[0035] Based on the carrot test data in Table 2, this invention is significantly effective in delaying browning and extending shelf life: The browning index (ΔE) increased slowly, from 0.22 on Day 0 to 3.61 on Day 12, an increase of 3.39 over 12 days. In contrast, the ΔE of the traditional hot water rinsing group increased from 0.20 to 6.81 (an increase of 6.61), and the 0.2% citric acid soaking group increased from 0.20 to 4.35 (an increase of 4.15). Especially on Day 7, the ΔE of this invention (2.55) was 55.3% lower than that of the hot water rinsing group (5.71) and 29.7% lower than that of the citric acid group (3.63). Regarding nutrient retention, the carotene retention rate of this invention was 84.33% on Day 12, which was 1.4 times that of the hot water blanching group (60.25%) and 1.1 times that of the citric acid group (76.63%). The vitamin C retention rate of this invention was 75.29% on Day 12, which was 1.42 times that of the hot water blanching group (53.12%) and 4.4% higher than the citric acid group (72.10%). With ΔE ≤ 3.0 as the acceptable threshold for the product, the shelf life of carrots treated by this invention can be extended to 12 days at 4 ℃ (ΔE = 3.61 on Day 12, close to the threshold), which is at least 5 days longer than the traditional hot water blanching process (ΔE = 5.71 on Day 7, which exceeds the standard) and 2-3 days longer than the citric acid soaking process (ΔE = 4.35 on Day 12). This fully demonstrates that this invention can effectively delay browning and extend the shelf life of the product.

[0036] Table 2 Comparison of carrots treated by the present invention with those treated by traditional processes.

[0037] Example 3: A process for preventing browning in low-hardness fruits and vegetables (scallions) through precision cutting and synergistic treatment with pulsed intense light. The specific implementation steps are as follows: 1. Raw material pretreatment: Select fresh scallions (variety: four-season scallions, plant height 20~30 cm, stem diameter 0.3~0.5 cm, hardness 0.5~0.8 kg / cm²), remove soil from the roots and withered yellow leaves, rinse with clean water and drain to ensure there is no free water on the surface.

[0038] 2. Automatic feeding and vision positioning: (1) Feeding control: The pre-treated scallions enter the skirt belt conveyor (width 15 cm, skirt height 5 cm, cross plate spacing 10 cm), the conveying speed is set to 0.5 m / s, driven by the drive motor 13, the cross plate 12 and the anti-slip skirt conveyor belt 11 work together to prevent the cucumbers from rolling, and then the vibrating feeding plate 14 is used to orient and sort them to ensure that the scallion roots face forward or backward; (2) Dual vision detection trigger: When the scallions enter the light-shielding box 221 (size 80 cm × 50 cm × 50 cm, with aluminum reflective film on the inner wall) of the machine vision positioning unit along the anti-slip conveyor belt 211, the side-mounted infrared sensor 222 is blocked, and a signal is sent to the industrial control computer, which simultaneously triggers the surface light source 223 to light up and the CCD camera 225 to take pictures.

[0039] (3) Data acquisition and processing: CCD camera 225 acquires RGB images and transmits them to the industrial control computer via Ethernet. The pre-trained YOLOv5 model (trained with about 5,000 leafy vegetable images, mAP@0.5=0.91) is called to perform instance segmentation, and the scallion white and scallion leaf cutting baseline is marked. TOF sensor 224 synchronously acquires three-dimensional point cloud, calculates the spatial distance between the two ends of the scallion leaf, and fits the central axis by least squares method in combination with the contour data. The positioning information dataset (including contour parameters, scallion diameter, and cutting coordinates) is transformed (aligned with the coordinate system of the cutting unit) and then sent to PLC via bus.

[0040] 3. Variable-pitch cutting and waste treatment (1) Knife assembly parameter configuration: The PLC determines the hardness of the scallion (0.5~0.8 kg / cm² < 3 kg / cm²) based on the positioning data, calls the variable pitch cutting unit 31, automatically selects 7 cam plate groove type cutters (blade thickness 0.1 mm), drives the slider 314 to move along the ball linear guide rail 313 through the servo motor B311, sets the end spacing of the variable pitch guide groove 316 to 5 mm (corresponding to the cutter spacing and slice thickness of 5 mm), and triggers the limit to complete the calibration when the positioning rod 312 reaches the bottom of the variable pitch guide groove 316; (2) Cutting execution: The scallions enter the cutting area with the conveyor belt. The servo motor B311 receives the PLC pulse signal (frequency 500 Hz) and drives the 315 cutter group to move downward at a speed of 50 mm / s. The first blade is aligned with the dividing line between the white part and the leaf part (cutting off the white part). The cutting pressure is set to 20 N (feedback in real time through the pressure sensor). After cutting, the conveyor belt moves forward 70 mm (total coverage length of the cutter group). The cutter group repeats the cutting action until the cutting length covers the length of the leaf part. The cutting cycle of a single scallion is 2.2s. (3) Waste separation: After being cut, the scallions enter the feeding unit 32 along the conveyor belt (speed 0.5 m / s). When the infrared sensor 321 detects the waste scallion whites, it sends a signal to the PLC, which drives the feeding cylinder 323 to extend within 100 ms and push the waste to the side feeding trough 322. The qualified scallion leaf segments continue to be conveyed to the next process.

[0041] 4. Pulsed intense light inactivation treatment (1) Material sorting: qualified slices are sorted into single layers by silicone squeegee 41 to avoid overlapping and obstruction, and enter the pulse strong light treatment chamber 43 (volume 0.5 m³, inner wall made of 304 stainless steel, surface matte treatment to reduce reflection interference) via heat-resistant conveyor belt 42. The conveying speed is controlled by servo motor.

[0042] (2) Parameter linkage control: The PLC calculates the pulse intensity light trigger frequency based on the slice thickness (5 mm) and conveying speed (0.5 m / s): f = v×n / 60 = (0.5×1000 mm / s ÷ 5 mm / s)×1 time / 60 = 1.7 Hz, and sends a trigger signal to the pulse intensity light transmitter 432, where v is the slicing rate (slices / minute) and n is the number of pulses processed in a single operation; (3) Intense light treatment: A pulsed intense light source 434 (wavelength 200~400 nm, main wavelength 254 nm) is installed at the top of the chamber 431 (10 cm away from the slice surface). The single pulse energy density is 1 J / cm², the pulse width is 50 μs, the single irradiation time is 100 ms, and a total of 1 treatment is performed, with a cumulative irradiation energy of 1 J / cm². The nitrogen circulation system 435 (including a scroll compressor, flow rate 10 L / min) in the chamber 431 is continuously filled with 99.99% high-purity nitrogen. The oxygen sensor 433 detects the oxygen concentration in real time. When the concentration is >0.5%, the PLC controls the solenoid valve to increase the nitrogen flow rate to 20 L / min to ensure that the oxygen concentration is <0.5% throughout the treatment. After treatment, the PPO activity is detected (using the catechol colorimetric method), and the inhibition rate is 90.66%. There is no burn on the slice surface.

[0043] 5. Nano-coating for color protection (1) Preparation of coating solution: A mixed solution of 0.5 wt% chitosan (molecular weight 10000 Da, degree of deacetylation 90%) and 0.1 wt% nanocellulose (length about 500 nm, diameter about 20 nm) was prepared, magnetically stirred, filtered through a 0.22 μm filter membrane, and stored in a constant temperature storage tank at 4 ℃.

[0044] (2) Spraying parameter control: The PLC controls the flow rate of the peristaltic pump (model: BT100-2J) to 3 mL / min based on the surface area of ​​the slice (the area of ​​a single slice is about 0.55~1.2 cm²). The coating liquid is delivered to the atomizing nozzle (4×2 matrix arrangement, nozzle diameter 0.5 mm) of the atomizing sprayer 513 through the liquid supply pipe (inner diameter 4 mm). Compressed air (0.1 MPa) is used to stabilize the pressure through the pressure reducing valve, so that the droplets are atomized into tiny particles.

[0045] (3) Coating and recycling: The slices enter the sealed spray chamber 51 (volume 0.3 m³), ​​and pass through the spraying area under the drive of the conveying roller 53 (rotation speed 30 rpm, surface covered with silicone anti-slip layer). The atomized droplets are evenly attached to the surface of the slices. The unattached coating liquid is collected by the bottom coating liquid recycling tank 52, filtered by the filter screen and recycled.

[0046] 6. Finished product inspection The treated scallion segments were stored at 4 ℃ and tested at 0, 3, 7, and 12 days. Table 3 shows the quality test results of the scallion segments treated according to this invention compared with those processed using traditional methods. The browning index was determined using a CR-400 colorimeter; vitamin C was determined using the 2,6-dichlorophenolindophenol titration method; and the total phenol retention rate was determined using the Folin-Ciocalteu method.

[0047] Based on the test data of scallions in Table 3, this invention is significantly effective in delaying browning and extending shelf life: Regarding the delay of browning, the browning index (ΔE) of the scallions treated with this invention increased slowly, from 0.15 on Day 0 to 2.97 on Day 12, an increase of 2.82 over 12 days. In contrast, the ΔE of the 80°C hot water blanching group increased from 0.16 to 4.15 (an increase of 4.0), and the 0.1% citric acid soaking group increased from 0.12 to 3.27 (an increase of 3.15). Especially on Day 7, the ΔE of this invention (2.71) was 28.5% lower than that of the hot water blanching group (3.79) and 9.1% lower than that of the citric acid group (2.98). Regarding nutrient retention, the total phenol retention rate of this invention was 75.22% on Day 12, which was 1.91 times that of the hot water blanching group (39.29%) and 1.11 times that of the citric acid group (67.83%). The vitamin C retention rate of this invention was 65.29% on Day 12, which was 1.82 times that of the hot water blanching group (35.89%) and 4.8% higher than that of the citric acid group (62.27%). Regarding shelf life extension, with ΔE≤3.0 as the acceptable threshold for the product, the scallions treated by this invention can have a shelf life extended to 12 days at 4 ℃, which is at least 5 days longer than the traditional hot water blanching process and 2-3 days longer than the chemical soaking process, fully demonstrating that this invention can effectively delay browning and extend the shelf life of the product.

[0048] Table 3 Comparison of scallions treated by the present invention with those treated by traditional methods.

[0049] The above experimental results show that the present invention can dynamically adjust the cutting parameters (blade spacing, rotation speed) and pulsed light parameters (energy density, number of irradiations) according to the hardness, shape and other characteristics of different fruits and vegetables (such as scallions, carrots, cucumbers, etc.). Through modular design, it can realize continuous adaptation production of multiple varieties, effectively helping the fresh-cut fruit and vegetable industry to upgrade to intelligence and precision.

[0050] Unless otherwise specified in the above description, all parts are prior art, or can be implemented using existing technology. Furthermore, the specific embodiments described in this invention are merely preferred embodiments and are not intended to limit the scope of this invention. That is, all equivalent changes and modifications made within the scope of this invention should be considered within the technical scope of this invention.

Claims

1. A fresh-cut fruit and vegetable browning prevention and pulsed light treatment all-in-one machine, characterized in that, The device comprises a feeding unit, a machine vision positioning unit, a cutting unit, a pulse strong light processing unit and a nano coating unit which are sequentially arranged and cooperatively work. The feeding unit comprises a skirt transmission belt (11), a transverse partition plate (12), a driving motor (13) and a vibrating feeding disc (14) which are sequentially arranged on a feeding unit rack (15). The machine vision positioning unit comprises a conveying module (21) and a vision acquisition module (22) which are sequentially arranged on a vision unit rack (23). The cutting unit comprises a variable-distance cutting unit (31), a material pushing unit (32) and a rotary cutting unit (33) which are sequentially arranged. The pulse strong light processing unit comprises a silica gel pushing piece (41), a heat-resistant conveying belt (42), a pulse strong light processing bin (43) and a heat-resistant belt driving motor (44) which are sequentially arranged. The nano coating unit is arranged downstream of the pulse strong light processing bin (43), and the material is uniformly conveyed by a conveying roller (53) through a spraying unit.

2. The fresh-cut fruit and vegetable anti-browning precision cutting and pulse strong light processing integrated machine and method according to claim 1, characterized in that, The conveying module (21) comprises an anti-skid conveying belt (211), a servo motor A (212) and a conveying belt side plate (213). The vision acquisition module (22) comprises a light shielding box (221), a pair of infrared sensors (222), a surface light source (223), a TOF sensor (224) and a CCD camera (225). The pair of infrared sensors (222), the surface light source (223), the TOF sensor (224) and the CCD camera (225) are all arranged in the light shielding box (221). The light shielding box (221) top hangs two face light sources (223), and the face light source (223) is controlled synchronously with the CCD camera (225), and the CCD camera (225) and the TOF sensor (224) are integrated on the top end of the light shielding box (221) through a support, the optical axis is perpendicular to the antiskid conveyor belt (211), the light shielding box (221) is below a antiskid belt conveyor driven by a servo motor A (212) and controlled synchronously with the CCD camera (225) trigger signal, and the conveyor belt side plate (213) of the antiskid belt conveyor is provided with a pair of infrared sensors (222).

3. The fresh-cut fruit and vegetable anti-browning precision cutting and pulsed strong light treatment all-in-one machine and method according to claim 1, characterized in that, The variable-distance cutting unit (31) comprises a servo motor B (311), a positioning rod (312), a ball linear guide (313), a sliding block (314), a cutter (315), and a variable-distance guide groove (316). The cutter (315) is a cam plate groove type blade arranged in parallel, and the cutter (315) is fixed on the sliding block (314) with the blade vertically downward. The sliding block (314) is fixed on the ball linear guide (313), and the positioning rod (312) is fixed vertically on the side of the sliding block and connected with the variable-distance guide groove (316). When the push rod of the servo motor B (311) displaces downward to push the ball linear guide (313), the positioning rod (312) can only displace along the variable-distance guide groove (316), so that the sliding block (314) drives the cutter (315) to displace synchronously left and right until the positioning rod (312) reaches the bottom end of the variable-distance guide groove (313), so that the cutter (315) is arranged in parallel with a distance equal to the distance at the end of the variable-distance guide groove (316); The material pushing unit (32) comprises an infrared sensor (321), a distribution groove (322), and a material pushing cylinder (323). The infrared sensor (321) detects the position of waste materials and sends a signal to the material pushing cylinder (323) to apply a lateral initial speed to the materials. The waste materials are collected along the laterally arranged distribution groove (322). The rotary slicing unit (33) comprises a rotary cutter (332) with a shell (333) controlled by a servo motor C (331) to slice high-hardness materials.

4. The fresh-cut fruit and vegetable anti-browning precision cutting and pulsed strong light treatment all-in-one machine and method according to claim 1, characterized in that, The pulse strong light treatment bin (43) includes a bin body (431), a pulse strong light emitter (432), an oxygen sensor (433), a pulse strong light source (434), and a nitrogen circulation system (435). The bin body (431) contains the pulse strong light source (434), which is driven by the pulse strong light generator (432) and is arranged directly above the light source in the bin body (431). The light source is located directly above the heat-resistant conveying belt (42), which is driven by a servo motor to realize synchronous control of the speed and the light source triggering. The bin body (431) is provided with a nitrogen circulation system (435).

5. The fresh-cut fruit and vegetable anti-browning and pulse strong light treatment integrated machine and method according to claim 1, characterized in that, The spray bin (51) is provided with spray bin baffles (511) on both sides, an atomizing sprayer (513) is arranged above the spray bin (51), a liquid supply unit (512) is arranged on the atomizing sprayer (513), and a coating liquid recovery groove 52 is arranged at the bottom of the spray bin (51).

6. The fresh-cut fruit and vegetable anti-browning precision cutting and pulsed light treatment all-in-one machine and method of claim 1, wherein, A PLC control system is further included, which is electrically connected with the feeding unit, the machine vision positioning unit, the cutting unit, the pulse strong light treatment unit, and the nano coating color protection unit. The PLC control system is used for receiving sensing signals of each unit and coordinating and controlling actions of each unit.

7. A fresh-cut fruit and vegetable browning prevention and pulsed light treatment all-in-one machine and method, characterized in that, The method is applicable to the fresh-cut fruit and vegetable anti-browning and pulse strong light treatment integrated machine and method according to any one of claims 1 to 6, and includes the following steps: The feeding unit drives the fruits and vegetables to enter the skirt belt conveyor driven by the driving motor, the transverse partition plate cooperates with the skirt transmission belt to prevent the fruits and vegetables from rolling, and then the fruits and vegetables are directionally sorted through the vibrating feeding disc to ensure that the fruit stems are forward or backward; When the fruits and vegetables enter the light-shielded box of the machine vision positioning unit along with the conveying belt, the side-facing infrared sensor is blocked, a signal is sent to the PLC controller, the surface light source is synchronously started to light up, the CCD camera collects the RGB image, the ToF sensor synchronously collects the depth information, the Ethernet is used to transmit the information to the industrial computer, the pre-trained vision model is called to perform instance segmentation, the contour extraction is completed, and the fruit stem and tail cutting reference line are marked; The cutting unit determines the fruit and vegetable type and hardness according to the image information data, calls the variable-distance cutting unit, and selects different specifications of cam plate slot type cutters. The slider is driven by the servo motor B to move along the variable-distance guide groove, the distance at the end of the variable-distance guide groove is adjusted to correspond to different slice thicknesses, and calibration is completed when the positioning rod triggers the limit. After the fruits and vegetables enter the cutting area along with the conveying belt, the servo motor B receives the PLC pulse signal to drive the cutter group to translate downward, the first cutter aligns with the head cutting line to cut, the conveying belt runs forward by the total coverage length of the cutter group after cutting, the cutter group repeats the cutting action until the cutting is completed. When the infrared sensor detects the waste, a signal is sent to the ejector cylinder to extend and push the waste to the lateral distribution groove. The pulse strong light trigger frequency of the pulse strong light processing unit is sent by the PLC according to the slice thickness and the conveying speed, the pulse strong light source is installed on the top of the warehouse body, the nitrogen circulation system in the warehouse continuously fills high-purity nitrogen, the oxygen sensor detects the oxygen concentration in real time, and when the oxygen concentration is greater than the set value, the PLC controls the electromagnetic valve to increase the nitrogen flow to ensure that the oxygen concentration is lower than the set value during the whole processing; The nano coating unit adopts a mixed solution of chitosan and nanocellulose, and the peristaltic pump controlled by the PLC according to the slice density delivers the coating liquid to the nozzle of the atomizing sprayer through the liquid supply pipe, compressed air passes through the pressure reducing valve to stabilize the pressure, so that the liquid droplets are atomized into small particles and uniformly adhere to the surface of the slice, and the unattached coating liquid is collected by the bottom recovery tank and recycled after filtration.

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