Soft food material modification, sterilization and enzyme deactivation device based on high-voltage electrostatic field and application of soft food material modification, sterilization and enzyme deactivation device

Abstract

The invention relates to a soft food material modification, sterilization and enzyme deactivation device based on a high-voltage electrostatic field and application thereof, and belongs to the technical field of food processing and equipment manufacturing. The device comprises a food material conveying system, a high-voltage electrostatic field processing system, a food material collecting system, a direct-current voltage supply system and a control system. The food material conveying system conveys soft food materials to the high-voltage electrostatic field processing system, the food materials are modified, sterilized and deactivated under the action of the direct-current voltage supply system, the food materials are collected through the food material collecting system, and the control system controls the whole system to operate. By utilizing the molecular polarization mechanism and effect and adopting the ultrahigh-voltage direct-current power supply, the eccentric rotor and the metal microporous plate structure to cooperate, the continuous conveying process of the soft food materials is realized to obtain high-strength charge density per unit volume, so that the physicochemical properties of the food materials are changed, and the purposes of sterilization and enzyme deactivation are achieved.

Description

Technical Field

[0001] The invention relates to a device for modifying and sterilizing soft food materials based on a high-voltage electrostatic field and application thereof, belonging to the technical field of food processing and equipment manufacturing. Background Art

[0002] Sterilization and enzyme inactivation is one of the most effective methods for food preservation and has been widely used in almost all fruit and vegetable food production fields. At present, food sterilization and enzyme inactivation technologies are mainly divided into two categories: thermal processing and non-thermal processing. Thermal sterilization and enzyme inactivation processing technology has been widely used in the food industry because of its mature development and low investment cost. Thermal sterilization methods such as high temperature sterilization and pasteurization extend the shelf life but are prone to cause loss of nutrients, changes in color, flavor and texture. Non-thermal sterilization achieves antibacterial or sterilization by destroying the cell wall or membrane structure of microorganisms through non-thermal effects such as ultrasonic cavitation, radiation, ultra-high pressure, electromagnetic fields and other physical fields. In addition to microbial safety, the inactivation of spoilage enzymes is also necessary to extend the shelf life. Substrates and enzymes are confined inside the food. In various processing steps such as immersion, pressing or extrusion, the enzyme contacts the substrate, resulting in product browning, phase separation and viscosity changes.

[0003] Soft food is between solid and liquid food. Generally speaking, it is easy to chew, swallow, digest and absorb. At present, most soft food, such as vegetable sauce, honey, meat paste, etc., are sterilized and inactivated by heat treatment, but consumers' demand for soft products with higher quality and fresher taste is growing rapidly. In recent years, non-thermal sterilization and enzyme inactivation technology has received great attention because it can provide soft products with better quality and fresher taste. Some studies have shown that high-voltage electrostatic field technology can change the electrical properties of food, destroy the secondary and tertiary structures of enzyme molecules, damage the cell structure of microorganisms and the molecular structure of DNA or RNA in cells; in addition, high-voltage electrostatic field technology can also modify food materials to make them have better functional properties, such as processed fruit and vegetable sauces are more resistant to high temperatures in baking, and the gel strength is improved. Therefore, high-voltage electrostatic field technology has become an important development direction for improving the traditional soft food sterilization and enzyme inactivation processing technology. However, the existing high-voltage electrostatic field treatment technology and equipment have problems such as low charge density of food materials, insignificant effect of food modification and sterilization and enzyme inactivation, and difficulty in achieving continuous processing. The present invention utilizes the polarization mechanism and effect of food materials under the action of high-voltage electrostatic field, and adopts the cooperative method of pressure extrusion and insulated eccentric rotor to continuously transport soft food materials to the metal microporous plate. Under the action of ultra-high voltage DC electric field, the food materials obtain high charge density per unit volume, thereby achieving the purpose of food material modification and sterilization and enzyme inactivation. The present invention not only meets the complex and diverse soft food material modification pretreatment by regulating the relevant parameters of the process and the device, but also can achieve the needs of directional enzyme inactivation and sterilization for different soft food materials. In addition, this patent can also be used for the modification and preparation of food 3D printing food materials to improve printing accuracy and printing quality.

[0004] Chang Zhengshi, Tian Ye, and Liu Junchi (2024) disclosed an invention patent for "A non-thermal processing process and device for fruit and vegetable juice based on high-voltage pulsed electric field technology" (202410117527.6). This patent uses high-voltage pulsed electric field technology to achieve uninterrupted production of various types of non-thermal sterilization fruit and vegetable juices, thereby improving the overall quality of fruit and vegetable juices. However, this patent cannot passivate a variety of enzymes in fruit and vegetable juices, is not suitable for juices with high turbidity, and cannot be applied to non-thermal processing of soft ingredients. The difference of the present invention is that it can achieve continuous high-voltage electrostatic field sterilization and enzyme inactivation of soft ingredients, while at the same time achieving modification of soft ingredients and improving the quality and functionality of soft ingredients.

[0005] Zhang Ruiyang, Meng Die, Wang Yanping, Bagenna, Fan Qicheng, Liu Hua, Sun Jun, and Liu Yapeng (2020) disclosed an invention patent for "An Ohmic Sterilization Method for Large-Grain Jam" (patent application number 202010460033.X). This patent uses ohmic sterilization technology to sterilize granular jam, which can maintain the integrity of fruit particles in the jam to the greatest extent, and help improve the texture, color, taste and nutritional value of jam and jam-containing foods. However, this patent uses thermal sterilization, which is only suitable for foods without heat-sensitive ingredients. The difference of the present invention is that the high-voltage electrostatic field treatment technology is a non-thermal processing, which not only achieves the purpose of effective modification and sterilization and enzyme removal of food materials, but also realizes the maximum retention of heat-sensitive components, and comprehensively improves the sterilization and enzyme removal processing quality of food materials.

[0006] Feng Zhibiao, Liu Buwei, Tian Bo, and Wang Huiting (2020) disclosed an invention patent for "An ultrasonic-microwave synergistic egg white liquid sterilization process" (patent application number 202010752021.4). The patent first uses ultrasonic treatment to evenly disperse the egg white liquid, and then uses a combined microwave and ultrasonic treatment to kill the microorganisms therein. The patent combines ultrasound with microwaves to make the sterilization more uniform and improve the functional properties of the egg white liquid, but the microwaves in this patent have a thermal effect and do not have non-thermal sterilization characteristics, and the patent does not have an enzyme-killing effect and is not suitable for continuous non-thermal processing of soft foods. The difference of the present invention is that while the high-voltage electrostatic field continuously kills microorganisms, it can also solve problems such as enzyme passivation and food modification, and it is a non-thermal sterilization, which has a more significant retention of nutrients.

[0007] Qian Jingya, Chen Shubei, and Zhou Cunshan (2019) disclosed an invention patent for "A method for sterilizing soybean paste by thermally coupled multi-frequency ultrasound" (patent application number 201910451070.1). This patent uses a thermally coupled multi-frequency ultrasound method to sterilize soybean paste, but this patent belongs to a low-temperature thermal sterilization method, and has no significant effect on enzyme passivation or inhibition of enzyme activity. The difference of the present invention is that it uses a high-voltage electrostatic field for continuous sterilization and enzyme inactivation non-thermal processing technology, which not only effectively sterilizes and inactivates soft ingredients, but also can modify them to improve the nutrient retention and functional properties of soft ingredients.

[0008] Wang Yuchuan, Yang Dongmei, Wang Bo, Liu Jiguang, Liu Aiping, Sun Anlun, and Xu Bangsheng (2023) disclosed an invention patent for "Device and application of pressure atomization and electrospraying to inactivate enzymes and sterilize liquid foods" (patent application number 202311812318.5). This patent uses a synergistic method of pressure atomization and electrospraying to inactivate enzymes and sterilize fruit and vegetable juices in a targeted manner. However, this patent is suitable for sterilizing and deactivating enzymes in fruit and vegetable juices, and cannot meet the sterilization and deactivation of soft fruit and vegetable sauce products. The difference of the present invention is that it uses a high-voltage electrostatic field for continuous sterilization and enzyme inactivation and non-thermal processing technology to achieve the sterilization and deactivation of soft food materials, while also having a food modification effect and improving the printability of food materials.

[0009] Sun Huaze, An Fengsong, and Jiang Yihong (2024) disclosed a utility model patent for "a high-temperature sterilization device for fruit and vegetable puree" (patent application number 202420118953.7). This patent uses an intermittent telescopic stirring method to stir the fruit and vegetable puree in all directions during the sterilization process, thereby improving the uniformity of sterilization of the fruit and vegetable puree. However, this patent adopts a thermal processing method, which is suitable for non-heat-sensitive ingredients, and has certain limitations in sterilizing heat-sensitive ingredients. The difference of the present invention is that it adopts high-voltage electrostatic field non-thermal processing technology to achieve sterilization and enzyme inactivation at room temperature during the continuous transportation of soft ingredients, thereby retaining the nutrients and functional characteristics of the ingredients to the maximum extent, while also having the effect of modifying the ingredients and improving the gel strength of the fruit and vegetable puree.

[0010] Jiang Hao, Liang Yumei, Guo Jinan, and Xing Youyi (2022) disclosed an invention patent for "Application of radio frequency modified starch in the preparation of special raw materials for 3D printing" (patent application number 202211228591.9). This patent modifies starch through a radio frequency processor, and the problem of starch sticking to the wall is improved after modification; the extrudate has strong fluidity and relatively high printing accuracy, which improves the lubricity and mechanical strength of the product. However, this patent has a thermal effect, and this patent does not have a bactericidal and enzyme-inactivating effect, and has certain limitations. The difference of the present invention is that it adopts high-voltage electrostatic field non-thermal processing technology to modify soft ingredients while sterilizing and inactivating enzymes, thereby improving the gel strength of fruit and vegetable purees and making them more suitable for subsequent 3D printing processing.

[0011] Saleh Al-Ghamdi, Chandrashekhar R.Sonar, Juhi Patel, Zeyad Albahr, Shyam S. Sablani (Food Control, 2020, 107233) studied the effects of heat-assisted high-pressure sterilization on the quality of low-acid fruit and vegetable purees. The study analyzed the effects of heat-assisted high pressure on the quality of ascorbic acid, β-carotene, chlorophyll, etc. of pumpkin, butternut squash, peas, beetroot and purple sweet potato purees. The results show that heat-assisted high-pressure treatment can retain the vitamin C content, but anthocyanins, betaine, etc. are significantly reduced. The difference of the present invention is that high-voltage electrostatic field non-thermal processing technology is used to achieve sterilization and enzyme inactivation at room temperature during the continuous transportation of soft ingredients, thereby maximizing the retention of nutrients and functional properties of the ingredients, while improving the physical and chemical properties of the ingredients and retaining the gel strength of fruit and vegetable purees.

[0012] Chaminda P. Samaranayake, Sudhir K. Sastry (Food Chemistry, 2016, 199, 265-272) studied the effects of electric fields of different frequencies on the activities of pectin methylesterase and polygalacturonase in tomato pulp. The results of this study showed that low-frequency field strength at a constant temperature (65°C) had a statistically significant effect on the activity of pectin methylesterase, but the effect of higher-frequency electric fields on the two enzymes was negligible. However, this study did not analyze the effect of variable-frequency electric fields on the quality of tomato pulp. The difference of the present invention is that high-voltage electrostatic field technology is used to obtain a high unit volume charge density during the continuous transportation of soft fruit and vegetable sauce ingredients, which not only effectively inactivates harmful enzymes in the ingredients, but also effectively kills foodborne pathogens. At the same time, it can improve the physical and chemical properties of the ingredients and retain the gel strength of the fruit and vegetable puree.

[0013] In short, the technology and equipment for modifying soft food and sterilizing enzymes based on high-voltage electrostatic fields have not been reported at home and abroad. The present invention will be an innovation to fill this technical gap in China. Summary of the invention

[0014] The purpose of the present invention is to overcome the above-mentioned shortcomings and provide a device for modifying and sterilizing soft food based on high-voltage electrostatic field and its application, which adopts ultra-high voltage DC power supply, eccentric rotor and metal microporous plate structure to achieve high-intensity unit volume charge density in the continuous conveying process of soft food, and regulate the physical and chemical properties and microbial properties of food from the molecular level.

[0015] The technical solution of the present invention is a device for modifying and sterilizing soft food materials based on a high-voltage electrostatic field, which is characterized by comprising a food material conveying system, a high-voltage electrostatic field processing system, a food material collection system, a DC voltage supply system and a control system;

[0016] The food conveying system conveys soft food to the high-voltage electrostatic field processing system, modifies and sterilizes the food under the action of the DC voltage supply system, and collects the food through the food collection system; the control system controls the operation of the food conveying system, the DC voltage supply system, the high-voltage electrostatic field processing system and the food collection system.

[0017] Furthermore, the food delivery system includes a high-pressure gas cylinder, a cylinder, an extrusion rod, a support tube, an extrusion tube, a delivery tube and a distribution tube; the high-pressure gas cylinder is connected to the cylinder through a pipeline, and the extended end of the cylinder is fixedly connected to the extrusion rod by a thread; the extrusion rod is connected to the support tube, and an extrusion tube is arranged in the support tube, and a piston is installed in the extrusion tube; the extrusion tube is connected to the delivery tube, and the delivery tube is connected to the distribution tube;

[0018] The high-voltage electrostatic field treatment system comprises a first support plate, a screw rod, a treatment container, a detachable fixing device, a support member, a second support plate and a metal microporous plate; the treatment container is fixed between the first support plate and the second support plate by a plurality of screw rods; the distribution pipe is connected to the treatment container; an arc-shaped metal microporous plate is provided on the lower outer surface of the treatment container, a support member is provided under the metal microporous plate, and the two are sealed by a sealing plate; the metal microporous plate is relatively fixed to the treatment container by a detachable fixing device; the support member is also fixed between the first support plate and the second support plate;

[0019] The food collection system comprises a first drive motor, a first coupling, a first bushing, a second drive motor, a second coupling, a second bushing, a collector, an eccentric rotor, an extrusion screw, a rotor shaft, a screw shaft and a collection port; an eccentric rotor is arranged inside the processing container, rotor shafts are arranged at both ends of the eccentric rotor, the rotor shaft at one end passes through the first bushing and is connected to the first drive motor through the first coupling, and the rotor shaft at the other end passes through the bushing provided with a sealing ring; an extrusion screw is arranged inside the support member, screw shafts are connected at both ends of the extrusion screw, the screw shaft at one end passes through the second bushing and is connected to the second drive motor through the second coupling, and the screw shaft at the other end is fixed to the collection port; the collector is connected to the extrusion screw outlet through the collection port;

[0020] The DC voltage supply system includes an electrode, a high-voltage power supply connection line and an ultra-high voltage DC power supply; the electrode is fixed on a metal microporous plate and connected to the ultra-high voltage DC power supply through a high-voltage power supply line;

[0021] The control system comprises a control cabinet.

[0022] Furthermore, the food delivery system also includes a pressure regulating valve and a reversing valve; the pressure regulating valve and the reversing valve are sequentially arranged on the pipeline connecting the high-pressure gas cylinder and the gas cylinder.

[0023] Furthermore, the bottom of the processing container in the high-voltage electrostatic field processing system is a mesh structure.

[0024] Furthermore, the detachable fixing device is specifically a fastening belt or a cable tie, etc.

[0025] Furthermore, the metal microporous plate is a double-layer structure, and the double-layer mesh is fixed by spot welding.

[0026] Furthermore, the mesh structure of the processing container has an aperture of 5 to 10 mm; the inner layer mesh of the metal microporous plate has a thickness of 1 to 3 mm and an aperture of 2 to 3 mm, and the outer layer mesh has an aperture of 100-1000 mesh.

[0027] Furthermore, the first support plate, the screw rod, the processing container, the support member and the second support plate are all made of insulating materials; and the metal microporous plate is made of stainless steel.

[0028] Furthermore, the food collection system also includes a spring and a scraper; the eccentric rotor is a cylindrical structure, with a plurality of grooves of the same length as the eccentric rotor in the middle, a spring is arranged in the groove, a scraper is connected to the front end of the spring, and the scraper is the same length as the eccentric rotor;

[0029] The center line of the eccentric rotor is parallel to the center axis of the processing container, but does not overlap; the gap between the eccentric rotor and the processing container is adjustable, and the minimum gap is 0.01mm;

[0030] The gap between the two end surfaces of the eccentric rotor and the first support plate and the second support plate is less than 0.01 mm;

[0031] Furthermore, the first drive motor and the second drive motor are both speed-regulating motors with a speed regulation range of 0-100 rpm;

[0032] Furthermore, the second coupling, the second sleeve, the scraper, the extrusion screw and the collector are all made of insulating materials.

[0033] Furthermore, the electrodes in the DC voltage supply system are stainless steel screws welded on the metal microporous plate; the ultra-high voltage DC power supply includes positive and negative high voltage DC power supplies with a voltage range of -100 to +100 kV.

[0034] The device is applied to the modification and sterilization and enzyme-killing processing of soft food materials such as fruit and vegetable sauces.

[0035] Further, the steps are:

[0036] (1) Food material preparation: prepare soft food materials, load them into the extrusion tube, install the piston, and install the extrusion tube into the support tube;

[0037] (2) Parameter settings:

[0038] According to the preliminary experiments and electrical characteristics of soft food, select the type of ultra-high voltage DC power supply and set the voltage value;

[0039] According to the soft food pre-experiment and processing objectives, the cylinder working pressure is set through the pressure regulating valve, and the speed of the first driving motor is set;

[0040] According to the soft food pre-experiment and processing objectives, the specifications of the metal microporous plate are selected and installed under the processing container and fixed by a detachable fixing device;

[0041] According to the soft food preliminary experiment and processing objectives, the speed of the second driving motor is set;

[0042] (3) Operation and shutdown: Turn on the power of the control cabinet and start the operation program. The cylinder pushes the extrusion rod under the action of the reversing valve, and the extrusion rod pushes the piston in the extrusion tube to push the food out. The food reaches the distribution pipe through the conveying pipe and enters the processing container through the distribution pipe. The food is transported to the bottom of the processing container through the rotation of the eccentric rotor and the scraper, and passes through the mesh at the bottom of the processing container to enter the metal microporous plate. After being processed by the high-voltage DC electric field, the food enters the support member and enters the food collector driven by the extrusion screw.

[0043] When the food in the extrusion tube is extruded completely, the reversing valve is stopped, the cylinder extension rod is moved upward, the first drive motor and the second drive motor are stopped, and finally the ultra-high voltage DC power supply is stopped;

[0044] After replacing the extrusion tube, the reversing valve, the first drive motor, the second drive motor and the ultra-high voltage DC power supply are turned on in sequence; after the food out of the extrusion tube is completely extruded, the reversing valve, the first drive motor, the second drive motor and the ultra-high voltage DC power supply are stopped again; and similarly, the food is treated with a high-voltage electrostatic field until all the food processing is completed.

[0045] Furthermore, the method for preparing the food material in step (1) is as follows: fresh fruits and vegetables are sorted, washed, peeled or cored, microwave softened, pulped and filtered to obtain fruit and vegetable pulp; the fruit and vegetable pulp, sucrose or honey and fruit and vegetable powder are mixed, stirred and filtered in proportion to obtain a fruit and vegetable sauce soft food material.

[0046] The specific parameters are: microwave softening temperature 50-90°C, time 3-5min; fruit and vegetable pulp filter screen 100-800 mesh; fruit and vegetable pulp: sucrose / honey: fruit and vegetable powder are compounded according to a weight ratio of 1:0.60-0.20:0.01-0.30; fruit and vegetable sauce filter screen 100-800 mesh; the fruit and vegetable powder is processed by spray drying or freeze drying, and filtered through a 100-800 mesh screen.

[0047] Furthermore, in step (2):

[0048] The ultra-high voltage DC power supply types are positive power supply and negative power supply. The positive power supply voltage setting range is 50~100kV, and the negative power supply voltage setting range is -50~-100kV;

[0049] The working pressure of the food delivery system pressure regulating valve (2) is set at 0-0.3 MPa, and the rotation speeds of the first drive motor (9) and the second drive motor (12) are both 0-100 rpm.

[0050] Beneficial effects of the present invention:

[0051] (1) Compared with the existing thermal processing technology, the present invention adopts ultra-high voltage electrostatic field non-thermal processing technology, which not only realizes the modification and sterilization of soft food under room temperature conditions, but also can effectively retain heat-sensitive ingredients, improve the processing quality of food, and enhance the competitiveness of processing enterprises' products.

[0052] (2) Compared with the existing non-thermal processing technology, the present invention uses cylinder extrusion, eccentric rotor, microporous plate and extrusion screw to solve the problem of insulation and continuous transportation of soft food under high electrostatic field in the non-thermal processing process, thereby improving the non-thermal processing efficiency of food.

[0053] (3) Compared with the existing high-voltage electrostatic field processing technology, the present invention adopts an ultra-high voltage DC power supply and a microporous plate method to enable the food to obtain a high unit volume charge density, solve the problem of poor high-voltage electrostatic field modification and sterilization and enzyme inactivation effects on soft food, and expand the application scope of high-voltage electrostatic field processing technology.

[0054] (4) Compared with the existing food modification and sterilization and enzyme inactivation devices, the device of the present invention has the advantages of simple structure, convenient operation, reliable performance, safe insulation, high efficiency, low cost, etc., and is easy to commercialize. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 It is a schematic diagram of the overall system of the device of the present invention.

[0056] Figure 2 It is a cross-sectional view of the device of the present invention.

[0057] Figure 3 This is a half-section schematic diagram of the processing container and the support member of the present invention.

[0058] Figure 4 It is a schematic diagram of the control principle of the present invention.

[0059] Explanation of the reference numerals in the accompanying drawings: 1. high-pressure gas cylinder; 2. pressure regulating valve; 3. reversing valve; 4. cylinder; 5. extrusion rod; 6. support tube; 7. extrusion tube; 8. delivery tube; 9. first drive motor; 10. first coupling; 11. first bushing; 12. second drive motor; 13. second coupling; 14. second bushing; 15. first support plate; 16. lead screw; 17. distribution tube; 18. processing container; 19. detachable fixing device; 20. support member; 21. electrode; 22. second support plate; 23. high-voltage power supply connecting line; 24. ultra-high voltage DC power supply; 25. collector; 26. control cabinet; 27. eccentric rotor; 28. spring; 29. ​​scraper; 30. metal microporous plate; 31. extrusion screw; 32. rotor shaft; 33. screw shaft; 34. collecting port. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0061] Example 1: Device for modifying soft food materials and sterilizing and inactivating enzymes based on high-voltage electrostatic field

[0062] like Figure 1-4 As shown, it includes a food conveying system, a high-voltage electrostatic field treatment system, a food collection system, a DC voltage supply system and a control system; the food conveying system conveys soft food to the high-voltage electrostatic field treatment system, modifies and sterilizes the food under the action of the DC voltage supply system, and collects the food through the food collection system; the control system controls the operation of the food conveying system, the DC voltage supply system, the high-voltage electrostatic field treatment system and the food collection system.

[0063] The food delivery system comprises a high-pressure gas cylinder 1, a gas cylinder 4, an extrusion rod 5, a support tube 6, an extrusion tube 7, a delivery tube 8 and a distribution tube 17; the high-pressure gas cylinder 1 is connected to the gas cylinder 4 through a pipeline, and the extended end of the cylinder 4 is fixedly connected to the extrusion rod 5 through a thread; the extrusion rod 5 is connected to the support tube 6, and the support tube 6 is provided with an extrusion tube 7, and a piston is installed in the extrusion tube 7; the extrusion tube 7 is connected to the delivery tube 8, and the delivery tube 8 is connected to the distribution tube 17;

[0064] The high-voltage electrostatic field treatment system comprises a first support plate 15, a screw rod 16, a treatment container 18, a detachable fixing device 19, a support member 20, a second support plate 22 and a metal microporous plate 30; the treatment container 18 is fixed between the first support plate 15 and the second support plate 22 by a plurality of screw rods 16; the distribution pipe 17 is connected to the treatment container 18; an arc-shaped metal microporous plate (30) is provided on the outer surface below the treatment container 18, and a support member 20 is provided below the metal microporous plate 30, and the two are sealed by a sealing plate; the metal microporous plate 30 is relatively fixed to the treatment container 18 by the detachable fixing device 19; the support member 20 is also fixed between the first support plate 15 and the second support plate 22;

[0065] The food collection system includes a first drive motor 9, a first coupling 10, a first sleeve 11, a second drive motor 12, a second coupling 13, a second sleeve 14, a collector 25, an eccentric rotor 27, an extrusion screw 31, a rotor shaft 32, a screw shaft 33 and a collection port 34; an eccentric rotor 27 is provided inside the processing container 18, and rotor shafts 32 are provided at both ends of the eccentric rotor 27. The rotor shaft 32 at one end passes through the first sleeve 11 and is connected to the first drive motor 9 through the first coupling 10, and the rotor shaft 32 at the other end passes through a sleeve provided with a sealing ring; an extrusion screw 31 is provided inside the support member 20, and screw shafts 33 are connected at both ends of the extrusion screw 31. The screw shaft 33 at one end passes through the second sleeve 14 and is connected to the second drive motor 12 through the second coupling 13, and the screw shaft 33 at the other end is fixed on the collection port 34; the collector 25 is connected to the outlet of the extrusion screw 31 through the collection port 34;

[0066] The DC voltage supply system includes an electrode 21, a high-voltage power supply connection line 23 and an ultra-high voltage DC power supply 24; the electrode 21 is fixed on the metal microporous plate 30 and connected to the ultra-high voltage DC power supply 24 through the high-voltage power supply line 23;

[0067] The control system includes a control cabinet 26 .

[0068] The food delivery system further includes a pressure regulating valve 2 and a reversing valve 3; the pressure regulating valve 2 and the reversing valve 3 are sequentially arranged on the pipeline connecting the high-pressure gas cylinder 1 and the gas cylinder 4.

[0069] The bottom of the processing container 18 in the high-voltage electrostatic field processing system is a mesh structure; the metal microporous plate 30 is a double-layer structure, and the double-layer mesh is fixed by spot welding;

[0070] The mesh structure of the processing container 18 has an aperture of 5 to 10 mm; the inner layer of the metal microporous plate 30 has a thickness of 1 to 3 mm and an aperture of 2 to 3 mm, and the outer layer has an aperture of 100 to 1000 mesh;

[0071] The first support plate 15, the screw rod 16, the processing container 18, the support member 20 and the second support plate 22 are all made of insulating materials; the metal microporous plate 30 is made of stainless steel.

[0072] The food collection system further includes a spring 28 and a scraper 29; the eccentric rotor 27 is a cylindrical structure, with a plurality of grooves of the same length as the eccentric rotor 27 in the middle, a spring 28 is arranged in the groove, and a scraper 29 is connected to the front end of the spring 28, and the scraper 29 is the same length as the eccentric rotor 27;

[0073] The center line of the eccentric rotor 27 is parallel to the center axis of the processing container 18, but they do not overlap; the gap between the eccentric rotor 27 and the processing container 18 is adjustable, and the minimum gap is 0.01 mm;

[0074] The gaps between the two end surfaces of the eccentric rotor 27 and the first support plate 15 and the second support plate 22 are less than 0.01 mm;

[0075] The first drive motor 9 and the second drive motor 12 are both speed-regulating motors with a speed regulation range of 0-100 rpm; the second coupling 13, the second sleeve 14, the scraper 29, the extrusion screw 31 and the collector 25 are all made of insulating materials.

[0076] The electrodes 21 in the DC voltage supply system are stainless steel screws welded on the metal microporous plate 30; the ultra-high voltage DC power supply 24 includes positive and negative high voltage DC power supplies with a voltage range of -100 to +100 kV.

[0077] Example 2: Using the device of the present invention to modify hawthorn jam and sterilize and inactivate enzymes based on high-voltage electrostatic field

[0078] (1) Preparation of ingredients: Take out 1 kg of fresh hawthorn from the refrigerator, remove the rotten hawthorn, wash, remove the stems, remove the core, and protect the color. Then put the cored hawthorn into a microwave oven to soften it. The microwave power is 800 W, the product temperature is set to 80°C, and the softening time is 5 min. Take it out and crush it with a beater. The mass ratio of hawthorn to water is 2:1, and squeeze it out through a filter bag to obtain uniform hawthorn pulp; mix the hawthorn pulp and sucrose according to the formula ratio, stir, and extrude it through a filter bag to obtain hawthorn jam; load the hawthorn jam into the extrusion tube 7, install the piston, and then load the extrusion tube 7 into the support tube 6; the formula ratio of hawthorn pulp to sucrose is hawthorn pulp: sucrose at a weight ratio of 1:0.45.

[0079] (2) Parameter settings:

[0080] High-voltage DC power supply system power type selection and parameter setting: According to the preliminary experiment and the electrical characteristics of hawthorn sauce ingredients, the high-voltage DC power supply 24 type is selected as a positive high-voltage DC power supply, and the voltage setting value is +50kV;

[0081] The food delivery system operating parameter setting: according to the food pre-experiment and processing objectives, the working pressure of the pressure regulating valve 3 is set to 0.3MPa, the speed of the first driving motor 9 is set to 10rpm, and the metal microporous plate 30 is set to 800 mesh;

[0082] The operating parameter setting of the food collection system: according to the hawthorn sauce preliminary experiment, the speed of the second driving motor 12 is set to 5 rpm;

[0083] (3) Operation and shutdown: Turn on the power of the control cabinet 26, click the operation button, the cylinder 4 pushes the extrusion rod 5, the extrusion rod 5 pushes the hawthorn jam in the extrusion tube 7 to flow out, through the delivery tube 8 to the distribution tube 17, and then enters the processing container 18 through the distribution tube 17. The first drive motor 9 drives the eccentric rotor 27 to rotate, and the eccentric rotor 27 drives the scraper 29 to rotate. During the rotation of the scraper 29, the hawthorn jam is compressed and transported to the bottom of the processing container 18, passes through the mesh at the bottom of the processing container 18, enters the metal microporous plate 30, enters the support member 20 after being treated by the high-voltage electrostatic field, and enters the food collector 25 through the extrusion screw 31; after the hawthorn jam in the extrusion tube 7 is extruded, click the stop operation button, after replacing the extrusion tube 7, click the operation button again, and after the hawthorn jam in the extrusion tube 7 is extruded, click the stop button again; and so on, the hawthorn jam is treated by the high-voltage electrostatic field until the hawthorn jam is treated.

[0084] Experimental results: The total number of bacteria in hawthorn jam products based on high-voltage electrostatic field modification and sterilization and enzyme-killing processing was reduced from 4.62log CFU / g to 2.36log CFU / g, and the sterilization rate was ≥90%. The activity of polyphenol oxidase decreased from 20.6±0.17ΔA / min / mL to 2.1±0.23ΔA / min / mL, and the inactivation rate was >85%; the activity of peroxidase decreased from 64.00ΔA / min / mL to 5.6ΔA / min / mL, and the inactivation rate was >90%; the pectin methylesterase decreased from 6.3ΔA / min / mL to 1.7ΔA / min / mL, and the inactivation rate was >70%; compared with traditional hot water (90℃, 30min) processing, the gel strength increased from 11.52±2.78 to 17.22±0.57, the hardness increased by 45.93%, the total phenol increased by 31.11%, and the antioxidant capacity increased by more than 42.89%.

[0085] Example 3: Using the device of the present invention to modify tomato paste and sterilize and inactivate enzymes based on high-voltage electrostatic field

[0086] (1) Preparation of ingredients: Take out 1 kg of fresh tomatoes from the refrigerator, remove rotten tomatoes, wash and remove stems, and then put the tomatoes into a microwave oven to soften, with a microwave power of 800 W, a product temperature set to 60°C, and a softening time of 3 min. Take out and crush with a beater, and extrude through a sieve to obtain tomato pulp; mix the tomato pulp with sucrose and tomato powder according to the formula ratio, and extrude through a sieve to obtain tomato sauce; put the tomato sauce into the extrusion tube 7, install the piston, and then put the extrusion tube into the support tube 6. The formula ratio of tomato pulp, sucrose and tomato powder is tomato pulp: sucrose: tomato powder with a weight ratio of 1:0.10:0.25. The tomato powder is prepared by freeze drying and filtered through a 600-mesh sieve.

[0087] (2) Parameter settings:

[0088] Selection of power supply type and parameter setting of high-voltage DC supply system: According to the preliminary experiment and the electrical characteristics of ketchup ingredients, the high-voltage DC power supply 24 type is selected as a negative high-voltage DC power supply, and the voltage setting value is -60kV;

[0089] The food delivery system operating parameter setting: according to the food pre-experiment and processing objectives, the working pressure of the pressure regulating valve 3 is set to 0.2MPa, the speed of the first driving motor 9 is set to 15rpm, and the metal microporous plate 30 is set to 600 mesh;

[0090] The operating parameter setting of the food collection system: according to the ketchup pre-experiment, the speed of the second driving motor 12 is set to 8 rpm;

[0091] (3) Operation and shutdown: Turn on the power of the control cabinet 24, click the operation button, the cylinder 4 pushes the extrusion rod 5, the extrusion rod 5 pushes the ketchup in the extrusion tube 7 to flow out, through the delivery tube 8 to the distribution tube 17, and then enters the processing container 18 through the distribution tube 17. The driving motor 9 drives the eccentric rotor 27 to rotate, and the eccentric rotor 27 drives the scraper 29 to rotate. During the rotation process of the scraper 29, the ketchup is compressed and transported to the bottom of the processing container 18, passes through the mesh at the bottom of the processing container 18, enters the metal microporous plate 30, enters the support 20 after being treated by the high-voltage electrostatic field, and enters the food collector 25 through the extrusion screw 31; after the ketchup in the extrusion tube 7 is extruded, click the stop operation button, after replacing the extrusion tube 7, click the operation button again, and after the ketchup in the extrusion tube 7 is extruded, click the stop button again; and so on, the ketchup is treated by the high-voltage electrostatic field until all the ketchup is treated.

[0092] Experimental results: The total number of bacteria in tomato sauce products based on high-voltage electrostatic field modification and sterilization and enzyme inactivation was reduced from 4.23log CFU / g to 2.13log CFU / g, and the sterilization rate was ≥90%. The relative residual activities of pectin methylesterase and polygalacturonase were 28.13% and 41.51% respectively; compared with traditional hot water (90℃, 30min) processing, the gel strength increased from 8.23 ​​to 12.49, the hardness increased by 51.76%, the total carotenoids and lycopene increased by 42.71% and 60.19% respectively, and the antioxidant capacity increased by more than 50.11%.

[0093] The present invention utilizes the polarization mechanism and effect of high charge density molecules, and adopts the coordinated use of ultra-high voltage DC power supply, eccentric rotor and metal microporous plate structure to achieve high-intensity unit volume charge density in the continuous conveying process of soft food, and regulates the physical and chemical properties and microbial properties of food from the molecular level. The present invention solves the problems of continuous, non-thermal, directional modification and sterilization and enzyme removal of soft food, innovates the non-thermal sterilization and enzyme removal technology of soft food, broadens the application scope of high-voltage electrostatic field, provides technical support for continuous non-thermal physical processing of soft food, and realizes efficient and high-quality creation of soft food and products.

Claims

1. A device for modifying and sterilizing soft food materials based on high-voltage electrostatic field, characterized by: It includes food delivery system, high voltage electrostatic field processing system, food collection system, DC voltage supply system and control system; The food conveying system conveys soft food to the high-voltage electrostatic field processing system, modifies and sterilizes the food under the action of the DC voltage supply system, and collects the food through the food collection system; the control system controls the operation of the food conveying system, the DC voltage supply system, the high-voltage electrostatic field processing system and the food collection system.

2. The device for modifying soft food materials and sterilizing and inactivating enzymes based on high-voltage electrostatic field as claimed in claim 1, characterized in that: The food delivery system comprises a high-pressure gas cylinder (1), a gas cylinder (4), an extrusion rod (5), a support tube (6), an extrusion tube (7), a delivery tube (8) and a distribution tube (17); the high-pressure gas cylinder (1) is connected to the gas cylinder (4) via a pipeline, and the protruding end of the gas cylinder (4) is fixedly connected to the extrusion rod (5) via a thread; the extrusion rod (5) is connected to the support tube (6), an extrusion tube (7) is arranged in the support tube (6), and a piston is installed in the extrusion tube (7); the extrusion tube (7) is connected to the delivery tube (8), and the delivery tube (8) is connected to the distribution tube (17); The high-voltage electrostatic field treatment system comprises a first support plate (15), a screw (16), a treatment container (18), a detachable fixing device (19), a support member (20), a second support plate (22) and a metal microporous plate (30); the treatment container (18) is fixed between the first support plate (15) and the second support plate (22) by a plurality of screws (16); the distribution pipe (17) is connected to the treatment container (18); an arc-shaped metal microporous plate (30) is provided on the outer surface below the treatment container (18), and a support member (20) is provided below the metal microporous plate (30), and the two are sealed by a sealing plate; the metal microporous plate (30) is fixed relative to the treatment container (18) by the detachable fixing device (19); the support member (20) is also fixed between the first support plate (15) and the second support plate (22); The food collection system comprises a first drive motor (9), a first coupling (10), a first shaft sleeve (11), a second drive motor (12), a second coupling (13), a second shaft sleeve (14), a collector (25), an eccentric rotor (27), an extrusion screw (31), a rotor shaft (32), a screw shaft (33) and a collection port (34); an eccentric rotor (27) is arranged inside the processing container (18), rotor shafts (32) are arranged at both ends of the eccentric rotor (27), and the rotor shaft (32) at one end passes through the first shaft sleeve (11) and passes through the first shaft sleeve (11). The first coupling (10) is connected to the first drive motor (9), and the rotor shaft (32) at the other end passes through a shaft sleeve provided with a sealing ring; an extrusion screw (31) is provided in the support member (20), and screw shafts (33) are connected at both ends of the extrusion screw (31); the screw shaft (33) at one end passes through the second shaft sleeve (14) and is connected to the second drive motor (12) through the second coupling (13), and the screw shaft (33) at the other end is fixed to the collection port (34); the collector (25) is connected to the outlet of the extrusion screw (31) through the collection port (34); The DC voltage supply system comprises an electrode (21), a high-voltage power supply connection line (23) and an ultra-high voltage DC power supply (24); the electrode (21) is fixed on a metal microporous plate (30) and connected to the ultra-high voltage DC power supply (24) via a high-voltage power supply line (23); The control system comprises a control cabinet (26).

3. The device for modifying soft food materials and sterilizing and inactivating enzymes based on high-voltage electrostatic field as claimed in claim 2 is characterized by: The food delivery system further comprises a pressure regulating valve (2) and a reversing valve (3); the pressure regulating valve (2) and the reversing valve (3) are arranged in sequence on the pipeline connecting the high-pressure gas cylinder (1) and the gas cylinder (4).

4. The device for modifying soft food materials and sterilizing and inactivating enzymes based on high-voltage electrostatic field as claimed in claim 2, characterized in that: The bottom of the processing container (18) in the high-voltage electrostatic field processing system is a mesh structure; Furthermore, the metal microporous plate (30) is a double-layer structure, and the double-layer mesh is fixed by spot welding.

5. The device for modifying soft food materials and sterilizing and inactivating enzymes based on high-voltage electrostatic field as claimed in claim 4 is characterized by: The mesh structure of the processing container (18) has an aperture of 5 to 10 mm; the inner layer of the metal microporous plate (30) has a thickness of 1 to 3 mm and an aperture of 2 to 3 mm, and the outer layer has an aperture of 100 to 1000 mesh; Furthermore, the first support plate (15), the screw rod (16), the processing container (18), the support member (20) and the second support plate (22) are all made of insulating materials; and the metal microporous plate (30) is made of stainless steel.

6. The device for modifying soft food materials and sterilizing and inactivating enzymes based on high-voltage electrostatic field as claimed in claim 2, characterized in that: The food collection system further comprises a spring (28) and a scraper (29); the eccentric rotor (27) is a cylindrical structure, with a plurality of grooves having the same length as the eccentric rotor (27) in the middle, a spring (28) is arranged in the groove, a scraper (29) is connected to the front end of the spring (28), and the scraper (29) has the same length as the eccentric rotor (27); The center line of the eccentric rotor (27) is parallel to the center axis of the processing container (18), but does not overlap; the gap between the eccentric rotor (27) and the processing container (18) is adjustable, and the minimum gap is 0.01 mm; The gaps between the two end surfaces of the eccentric rotor (27) and the first support plate (15) and the second support plate (22) are less than 0.01 mm; Furthermore, the first drive motor (9) and the second drive motor (12) are both speed-regulating motors with a speed regulation range of 0-100 rpm; Furthermore, the second coupling (13), the second shaft sleeve (14), the scraper (29), the extrusion screw (31) and the collector (25) are all made of insulating materials.

7. The device for modifying soft food materials and sterilizing and inactivating enzymes based on high-voltage electrostatic field as claimed in claim 2, characterized in that: The electrodes (21) in the DC voltage supply system are stainless steel screws welded to the metal microporous plate (30); the ultra-high voltage DC power supply (24) includes positive and negative high voltage DC power supplies with a voltage range of -100 to +100 kV.

8. Use of the device according to any one of claims 1 to 7, characterized in that: It is used in the modification and sterilization and enzyme-inactivation processing of soft food ingredients such as fruit and vegetable sauces.

9. Use of the device according to any one of claims 1 to 7, characterized in that The steps are: (1) Food material preparation: prepare soft food material, load it into the extrusion tube (7), install the piston, and install the extrusion tube (7) into the support tube (6); (2) Parameter settings: According to the preliminary experiments and electrical characteristics of soft food materials, the type of ultra-high voltage direct current power supply (24) is selected and the voltage value is set; According to the soft food preliminary experiment and the processing target, the working pressure of the cylinder (4) is set by the pressure regulating valve (3), and the speed of the first driving motor (9) is set; According to the soft food pre-experiment and processing objectives, the specifications of the metal microporous plate (30) are selected and installed below the processing container (18) and fixed by a detachable fixing device (19); According to the soft food preliminary experiment and processing objectives, the rotation speed of the second driving motor (12) is set; (3) Operation and shutdown: Turn on the power of the control cabinet (26) and start the operation program. The cylinder (4) pushes the extrusion rod (5) under the action of the reversing valve (3). The extrusion rod (5) pushes the piston in the extrusion tube (7) to push the food out. The food reaches the distribution tube (17) through the conveying tube (8) and enters the processing container (18) through the distribution tube (17). The food is transported to the bottom of the processing container (18) through the rotation of the eccentric rotor (27) and the scraper (29), and passes through the mesh at the bottom of the processing container (18) and enters the metal microporous plate (30). After being processed by the high-voltage direct current electric field, the food enters the support member (20) and enters the food collector (25) driven by the extrusion screw (31). When the food in the extrusion tube (7) is completely extruded, the reversing valve (3) is stopped, the cylinder (4) extends its rod and moves upward, the first drive motor (9) and the second drive motor (12) are stopped, and finally the ultra-high voltage direct current power supply (24) is stopped; After the extrusion tube (7) is replaced, the reversing valve (3), the first drive motor (9), the second drive motor (12) and the ultra-high voltage direct current power supply (24) are started in sequence; when the extrusion of food from the extrusion tube (7) is completed, the reversing valve (3), the first drive motor (9), the second drive motor (12) and the ultra-high voltage direct current power supply (24) are stopped again; and the high-voltage electrostatic field treatment of food is performed in a similar manner until all food treatment is completed.

10. Application of the device according to claim 9, characterized in that: The method for preparing the food material in step (1) is as follows: sorting, washing, peeling or removing the core of fresh fruits and vegetables, softening by microwave, beating and filtering to obtain fruit and vegetable pulp; mixing the fruit and vegetable pulp, sucrose or honey and fruit and vegetable powder according to a certain proportion, stirring and filtering to obtain a soft food material of fruit and vegetable sauce; Furthermore, in step (2): The ultra-high voltage DC power supply types are positive power supply and negative power supply. The positive power supply voltage setting range is 50~100kV, and the negative power supply voltage setting range is -50~-100kV; The working pressure of the food delivery system pressure regulating valve (2) is set at 0-0.3 MPa, and the rotation speeds of the first drive motor (9) and the second drive motor (12) are both 0-100 rpm.

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