Apparatus and method for rapid drying and microbial reduction pretreatment of aquatic products

Abstract

An apparatus and method for rapid drying and microbial reduction pretreatment of aquatic products. The apparatus comprises a drying device, a cold plasma treatment system, and an activated gas recovery and circulation system. The drying device is mainly used for drying dehydration of aquatic products. The objectives of introducing a cold plasma non-thermal processing technique to treat aquatic products are: improving drying efficiency and sterilizing aquatic products during drying. Activated gas generated by cold plasma in a box body is recovered by the activated gas recovery and circulation system to prepare activated water having a high-efficiency sterilization capability, which is used for sterilization pretreatment of the dried material. A compressor can be further connected by means of a return gas channel so as to achieve heat energy recovery throughout the process and reduce energy loss.

Description

An apparatus and method for rapid drying and sterilization pretreatment of aquatic products Technical Field

[0001] This invention belongs to the field of aquatic product drying and processing technology, and particularly relates to an apparatus and method for rapid drying and sterilization pretreatment of aquatic products. Background Technology

[0002] my country boasts a large and diverse output of aquatic products, making them an important source of high-quality animal protein and an indispensable part of a healthy diet in China. Besides fresh sales, dried, frozen, and pickled aquatic products are currently the three main forms of aquatic product available on the market. Dried products, in particular, are popular among consumers due to their advantages such as convenient production, low energy consumption, unique flavor, and lack of typical negative health effects.

[0003] Currently, the main method for industrialized production of dried aquatic products is hot air drying, with a few companies using infrared drying and microwave drying. However, these methods generally suffer from drawbacks such as long drying times, high energy consumption, and severe quality degradation due to microbial proliferation. To address this issue, researchers have invented some novel methods for drying aquatic products. For example, Zhang Han et al. proposed a method for drying gelatinous aquatic products using medium- and short-wave infrared combined with ultrasonic pretreatment (ZL201210537889.8). This method utilizes ultrasound to pretreat the gelatinous aquatic products, followed by drying using a combined medium- and short-wave infrared-hot air drying device. The resulting products have advantages such as good color and structure retention, fast rehydration speed, and good restitution, but suffer from drawbacks such as long drying times and high energy consumption. Other researchers have modified commonly used aquatic product drying equipment to achieve faster drying rates and better product quality. For example, Wang Lin et al. proposed a microwave drying device for aquatic products based on the melting phase change temperature (CN202310800751.0). Compared with traditional microwave drying equipment, this device has advantages such as high drying efficiency, precise endpoint control, and clean and pollution-free production. However, this device only partially optimizes microwave drying equipment and does not include sterilization treatment, resulting in a shorter product shelf life. He Yina et al. proposed a through-flow internal circulation aquatic product drying device (ZL201911169784.X). This device consists of a housing and an internal circulation fan, and has advantages such as reasonable and compact structure, uniform heat distribution, high drying efficiency, and uniform drying. However, it is essentially still hot air drying, and its product quality is not significantly different from that of traditional hot air-dried products. Therefore, developing new drying equipment and methods for aquatic products to improve drying rates, product quality, and extend shelf life is an urgent need in the field of aquatic product drying.

[0004] Plasma refers to a mixed system of various particles generated by the ionization of a gas under a strong electric field. Cold plasma (CP) is a type of plasma, where the ion temperature and neutral particle temperature are much lower than the electron temperature, resulting in a system temperature close to room temperature. During cold plasma processing, various particles and reactive oxygen / nitrogen groups (ROS / RNS) are generated. Currently, research on this technology in the field of aquatic product processing mainly focuses on sterilization and preservation, with no reports on its application in promoting the drying of aquatic products. In fact, the various particles and chemically active groups generated by cold plasma bombard the surface of materials, altering the surface and internal microstructure through an etching effect, creating voids, thereby promoting moisture diffusion, improving the thermal properties of the material, increasing drying efficiency, and without affecting the sensory characteristics of the dried product. Furthermore, cold plasma also has a strong bactericidal effect and can significantly extend the shelf life of products.

[0005] In summary, developing a drying device and method for aquatic products based on the synergistic application of cold plasma is of significant practical importance to the field of aquatic product drying and processing. Summary of the Invention

[0006] To address the aforementioned drawbacks of traditional heat pump / air drying methods, this invention provides an apparatus and method for rapid drying and sterilization pretreatment of aquatic products. It utilizes cold plasma as an auxiliary technology in the drying process, aiming to solve the problems of long drying times, high energy consumption, and low efficiency. The active substances generated by the plasma are collected to create highly active water, which is then used in the sterilization pretreatment device before product drying, thereby achieving green, energy-saving, environmentally friendly, and highly efficient production.

[0007] To achieve the above, the technical solution adopted by the present invention is as follows:

[0008] A device for rapid drying and sterilization pretreatment of aquatic products, comprising drying equipment and a cold plasma treatment system, characterized in that:

[0009] The drying equipment includes a housing (100), an operation panel (101), an equipment switch (102), a compressor (103), a heating unit (104), a temperature and humidity sensor (105 / 106), a dehumidification outlet (107), a material tray (109), an automatic weighing device (110), and a dehumidifier (111). The operation panel (101) and the equipment switch (102) are respectively located on the front of the outer wall of the housing (100) and are used to set drying parameters and start and stop the drying equipment. The compressor (103), heating unit (104), temperature and humidity sensor (105 / 106), dehumidification outlet (107), material tray (109), automatic weighing device (110), and dehumidifier (111) are located in the housing. The inner cavity of the body (100); the compressor (103) and the dehumidifier (111) are respectively located at the bottom of the inner cavity of the body (100), and a heating unit (104) is provided above the compressor, and the compressor (103) is connected to the heating unit (104); a dehumidifier (111) is provided with a dehumidification port (107) at the top; the dehumidifier (111); the temperature and humidity sensors (105 / 106) are connected, and an automatic weighing device (110) is provided at the bottom of the material tray (109) to record the weight change of aquatic products in real time during the drying process; an air inlet (304) is provided on the lower right side of the body (100), and the air inlet (304) is connected to the compressor (103);

[0010] The cold plasma processing system includes a cold plasma generator (201), a cold plasma power supply (202), and a voltage controller (203). The cold plasma generator (201) is installed on the top panel of the inner cavity of the housing (100) and is located above the material tray (109). The material tray (109) is directly opposite the jet discharge port of the cold plasma generator (201). The cold plasma generator (201) is connected to the cold plasma power supply (202) and the voltage controller (203) respectively.

[0011] Furthermore, the activated gas recovery and recycling system includes an air outlet (301), a blower fan (302), an air inlet pipe (303), an air inlet (304), an exhaust pipe (305), an exhaust fan (306), a return air duct (307), an exhaust pipe (308), an ozone decomposition device (401), a nitrogen and oxygen absorption device (402), and an external water tank (501). The heating unit (104) has an air outlet (301) on the side facing the material tray (109). The blower fan (302) is installed in the inner cavity of the housing (100), and the air outlet (301) corresponds to the installation position of the blower fan (302). The ozone decomposition device (401) and the nitrogen and oxygen absorption device (402) are respectively located below the inner cavity of the housing (100). An exhaust pipe (305) is provided above the oxygen absorption device (402). The exhaust pipe (305) is provided with two exhaust pipes (308). One exhaust pipe (308) is connected to the ozone decomposition device (401) and the nitrogen-oxygen absorption device (402). The nitrogen-oxygen absorption device (402) is connected to the compressor (103) through the return air duct (307). The return air duct (307) is used to recover the hot airflow of the drying process for recycling, so as to realize the recycling of heat. The exhaust pipe is connected to the exhaust pipe (308) through the exhaust fan, which is used to draw the activated gas of the treated cold plasma into the exhaust pipe. The other exhaust pipe (308) is connected to the external water tank (501). The external water tank (501) is located on the left side of the box (100) and is used to collect the active substances generated by the cold plasma in the box (100).

[0012] Furthermore, it also includes an automatic lifting unit (108), which includes a motor (601) installed inside the housing (100). The output end of the motor (601) is connected to a transmission wheel (602). A stainless steel wire is provided on the transmission wheel (602). One end of the stainless steel wire is fixed to the transmission wheel (602), and the other end passes through an L-shaped column tube (603) and passes around a certain pulley (604). The other end is fixedly connected to the top panel of the housing (100) for connecting and lifting the cold plasma generator (201). One end of the top panel is clamped on a columnar slot plate (607) and can move along the columnar slot plate (607). The transmission wheel (602) is moved downwards to maintain the stability of the cold plasma generator (201). The transmission wheel (602) is equipped with a reducer (605) and a rotation sensor (606) for counting. The reducer (605) has the function of stopping the transmission wheel when the motor is paused or turned off. The information of the rotation sensor (606) is transmitted to the control panel (101) and the travel distance of the rise and fall can be displayed on the control panel (101) for easy reading and precise control of the distance between the jet discharge port of the cold plasma generator (201) and the material tray for easy processing of aquatic products. The control panel (101) is equipped with a switch button for controlling the motor (601). When turned on, it can control the stainless steel wire on the transmission wheel (602) to be lowered or retracted.

[0013] Furthermore, the cold plasma generator (201) includes an electrode (204), a cold plasma jet housing (205), and an air inlet pipe (303). The electrode (204) is disposed inside the cold plasma jet housing (205), and the air inlet pipe (303) is disposed on the cold plasma jet housing (205). The air inlet pipe (303) is connected to an external air pump or air inlet pipe to provide the gas required for cold plasma processing.

[0014] Furthermore, the electrode (204) is connected to the cold plasma power supply (202), and the cold plasma processing voltage is controlled by the voltage controller (203). The formed cold plasma is ejected in the form of a jet through the nozzle of the cold plasma jet shell (205) and acts on the aquatic products to be dried.

[0015] A method for rapid drying and sterilization pretreatment of aquatic products, characterized in that the treatment method specifically includes the following steps:

[0016] S1. Sterilization pretreatment: The aquatic products to be dried are placed in the activated water prepared in the water tank (501) for sterilization pretreatment;

[0017] S2. Sample preparation: Take the sterilized sample out of the water tank (501), place it on the material tray (109) to drain the water, and weigh it;

[0018] S3. Turn on the drying equipment: Press the equipment switch button to turn on the machine. The gas circulation system will start working at the same time. Then set the drying parameters on the operation panel. After the parameters are confirmed, the temperature inside the chamber (100) will start to rise. During the heating process, the heat flow will be reused through the gas circulation system to achieve energy saving and environmental protection, thereby achieving the purpose of rapid heating. When the temperature inside the chamber (100) rises to the difference ±1℃, put in the sample from step (2).

[0019] S4. Cold plasma treatment: During the drying process, the aquatic products can be treated with cold plasma at any time. The distance between the jet discharge port of the cold plasma generator (201) and the aquatic products is controlled by the automatic lifting unit (108). Air / argon is injected into the air inlet pipe, and the cold plasma power supply is turned on at the same time to treat the aquatic products with cold plasma.

[0020] S5. Product drying: After the cold plasma treatment is completed, open the automatic lifting unit (108) to adjust the position of the cold plasma generator, close the valve of the cold plasma working gas inlet pipe, and blow the active gas in the box into the gas purification device for decomposition and removal in a timely manner through the exhaust fan.

[0021] S6. Sampling and Packaging: After drying is complete, turn off the drying equipment and cold plasma power supply; take out the dried aquatic products, place them at room temperature for 3 minutes, cool them to room temperature, and then vacuum pack the products to obtain dried products.

[0022] Furthermore, in step S3, the drying parameters are specifically set as follows: drying temperature 60℃, humidity 20%, drying time 14h, and wind speed 2.5m / s.

[0023] Furthermore, in step S4, the frequency of the cold plasma treatment is 50-65 kHz, and the treatment time is 1-5 min.

[0024] Furthermore, in step S4, the distance between the jet discharge port of the cold plasma generator (201) and the aquatic product is 1-5 cm.

[0025] Furthermore, in step S4, the flow rate of air / argon injected into the intake pipe is 1.2-1.8 L / min.

[0026] Furthermore, in step S5, the moisture content of the aquatic products at different time points during the drying process is recorded by an automatic weighing device to determine the total time required for the drying endpoint. The method for determining the moisture content and calculating the drying endpoint time is as follows:

[0027] Moisture content was determined based on weight changes. The initial product weight M0 was recorded using an automatic weighing device, and the weights M of the aquatic products at different time points during the drying process were recorded. t and constant weight M e Calculate the moisture content and water content of MC according to formulas (1) and (2):

[0028] Where MC is the moisture content (g / g), M0 is the initial mass of the product, and M e For constant weight quality of the product, M t For any drying time, MR represents the moisture ratio, MC0 is the initial moisture content of the product, and MC is the product quality. t The moisture content of the product after drying for any time is given by t, where t is the drying time (h).

[0029] Based on the kinetic model of aquatic product drying, the moisture content and drying endpoint time are calculated by fitting mathematical equations to obtain the equation parameters. Four commonly used drying kinetic models A, B, C, and D are provided, and the calculation process is as follows: MR=exp(-Kt n ) (A) MR=Kexp(-nt) (B) MR=Kexp(-nt)+K1 (C) MR=1+Kt+nt 2 (D)

[0030] Wherein, K, n, and K1 are the unknown parameters (constant) of the model equation, which can be obtained by substituting the drying time t and the measured MR into the model for fitting.

[0031] After substituting the calculated moisture ratio into the equation and fitting iteratively, the parameters K, n, and K1 in model equations A, B, C, and D are calculated to obtain the equation that conforms to the change of moisture ratio of dried aquatic products with drying time t. Therefore, the drying time t required for the drying endpoint can be obtained by combining the obtained parameters and the expected MR value with equation (2).

[0032] Specifically, to verify whether the model is applicable to the dried aquatic products, it can be tested according to equations (3) and (4):

[0033] In equations (3) and (4), MRexp,i and MRpre,i represent the dimensionless MR values ​​of the experiment and prediction, respectively, N is the number of observations, and z is a constant of the model. Typically, after fitting, Ri 2 The closer χ is to 1, 2 The best-fitting model is achieved when the RMSE is closest to 0.

[0034] Compared with the prior art, the beneficial effects of the present invention are reflected in:

[0035] 1. This invention introduces a non-thermal processing technology for drying aquatic products with cold plasma assistance, which can solve the technical problems of slow initial heating, long drying time, and high energy consumption that exist in single heat pump drying.

[0036] 2. This invention reuses heat flow through a gas circulation system and recovers sensible heat from the heat flow, which helps maintain the chamber temperature, greatly reduces equipment energy consumption, and improves the efficiency of product drying.

[0037] 3. This invention utilizes various physical / chemical factors generated by cold plasma to destroy substances that hinder moisture diffusion and heat exchange during the drying process of aquatic products, increasing the micropores on the surface and the gaps between tissues, thereby promoting moisture diffusion and heat exchange in aquatic products, shortening the drying time, and without affecting the sensory characteristics of the dried products.

[0038] 4. This invention utilizes the strong microbial killing effect of cold plasma itself. Firstly, it can directly kill various microorganisms attached to the surface of aquatic products after processing, effectively controlling the growth and reproduction of microorganisms and ensuring the quality, safety and shelf life of dried aquatic products. Secondly, the active gas generated in the collection box is introduced into the water tank, and the bactericidal effect formed by the activation of water by the active gas is used to pre-sterilize and preserve aquatic products that are temporarily caught or about to be dried. Attached Figure Description

[0039] Figure 1 is a schematic diagram of the device for rapid drying and sterilization pretreatment of aquatic products according to the present invention.

[0040] The diagram is labeled as follows: 100. Cabinet, 101. Control Panel, 102. Equipment Switch, 103. Compressor, 104. Heating Unit, 105 / 106. Temperature and Humidity Sensor, 107. Exhaust Vent, 108. Automatic Lifting Unit, 109. Material Tray, 110. Automatic Weighing Device, 111. Dehumidifier, 201. Cold Plasma Generator, 202. Cold Plasma Power Supply, 203. Voltage Controller, 204. Electrode, 205. Cold Plasma Jet Shell, 301. Air Outlet, 302. Blower Fan, 303. Air Inlet Pipe, 304. Air Inlet, 305. Exhaust Pipe, 306. Exhaust Fan, 307. Return Air Duct, 308. Exhaust Pipe, 401. Ozone Decomposition Device, 402. Nitrogen and Oxygen Absorption Device, 501. Water Tank

[0041] Figure 2 is a schematic diagram of the cold plasma generator used in this invention.

[0042] The diagram is labeled as follows: 204. Electrode, 205. Cold plasma jet shell, 303. Inlet pipe.

[0043] Figure 3 is a schematic diagram of the automatic lifting unit in this invention.

[0044] The diagram is labeled as follows: 601. Motor, 602. Transmission wheel, 603. L-shaped column tube, 604. Fixed pulley, 605. Reducer, 606. Rotation sensor, 607. Columnar slot plate.

[0045] Figure 4 shows the moisture ratio variation curves during the mussel heat pump drying process in various examples of the present invention.

[0046] Figure 5 shows the calculation of the mussel heat pump drying endpoint time for each example using model C of the present invention. Detailed Implementation

[0047] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0048] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0049] The present invention will now be described in detail with reference to the accompanying drawings and exemplary embodiments.

[0050] Example 1

[0051] Referring to Figures 1, 2, and 3, an apparatus for rapid drying and sterilization pretreatment of aquatic products according to the present invention includes a drying device and a cold plasma treatment system, wherein:

[0052] The drying equipment includes a housing 100, an operation panel 101, an equipment switch 102, a compressor 103, a heating unit 104, temperature and humidity sensors 105 / 106, a dehumidification outlet 107, a material tray 109, an automatic weighing device 110, and a dehumidifier 111. The operation panel 101 and the equipment switch 102 are respectively located on the front of the outer wall of the housing 100, and are used to set drying parameters and start / stop the drying equipment. The compressor 103, heating unit 104, temperature and humidity sensors 105 / 106, dehumidification outlet 107, material tray 109, automatic weighing device 100, and dehumidifier 111 are located within the housing 100. The inner cavity of the housing 100; the compressor 103 and dehumidifier 111 are respectively located at the bottom of the inner cavity of the housing 100, and a heating unit 104 is provided above the compressor, and the compressor 103 is connected to the heating unit 104; a dehumidifier 111 is provided at the top of the dehumidifier 111; the temperature and humidity sensors 105 / 106 are connected, and an automatic weighing device 110 is provided at the bottom of the material tray 109 to record the weight change of aquatic products in real time during the drying process; an air inlet 304 is provided on the lower right side of the housing 100, and the air inlet 304 is connected to the compressor 103;

[0053] The cold plasma processing system includes a cold plasma generator 201, a cold plasma power supply 202, and a voltage controller 203. The cold plasma generator 201 is installed on the top panel of the inner cavity of the housing 100, and is located above the material tray 109, with the material tray 109 facing the jet discharge port of the cold plasma generator 201. The cold plasma generator 201 is connected to the cold plasma power supply 202 and the voltage controller 203 respectively.

[0054] The activated gas recovery and recycling system includes an air outlet 301, a blower fan 302, an air inlet pipe 303, an air inlet 304, an exhaust pipe 305, an exhaust fan 306, a return air duct 307, an exhaust pipe 308, an ozone decomposition device 401, a nitrogen and oxygen absorption device 402, and an external water tank 501. The heating unit 104 has an air outlet 301 on the side facing the material tray 109. The blower fan 302 is installed inside the housing 100, and the air outlet 301 corresponds to the installation position of the blower fan 302. The ozone decomposition device 401 and the nitrogen and oxygen absorption device 402 are respectively located below the inner cavity of the housing 100. An exhaust pipe 305 is installed above the chamber, and the exhaust pipe 305 is provided with two exhaust pipes 308. One exhaust pipe 308 is connected to the ozone decomposition device 401 and the nitrogen and oxygen absorption device 402, and the nitrogen and oxygen absorption device 402 is connected to the compressor 103 through the return air duct 307. The return air duct 307 is used to recover the hot airflow from the drying process for recycling, so as to realize the recycling of heat. The exhaust pipe is connected to the exhaust pipe 308 through an exhaust fan to draw the processed cold plasma activation gas into the exhaust pipe. The other exhaust pipe 308 is connected to an external water tank 501, which is located on the left side of the chamber 100 and is used to collect the active substances generated by the cold plasma inside the chamber 100.

[0055] The ozone decomposition device and nitrogen oxide adsorption device mainly utilize a heating plate to absorb moisture from the gas transported through the extraction pipe 305, and then recycle it through a multi-layered catalyst. The extraction pipe 305 transports the gas to be treated to the heating plate area. The heating plate is made of a highly efficient thermally conductive material, capable of rapidly heating to a preset temperature. As the gas passes through the heating plate, the moisture in the gas is absorbed and evaporated, removing moisture and increasing the adsorption efficiency of the subsequent catalyst. The gas, after dehydration by the heating plate, enters the multi-layered catalyst device. The catalyst device consists of multiple catalyst layers with different functions, each with its specific adsorption and reaction effects. As the gas passes through these catalyst layers sequentially, ozone decomposes into oxygen under the action of the catalyst, while nitrogen oxides are adsorbed and fixed on the catalyst surface. The multi-layered structure of the catalyst not only increases the contact area between the gas and the catalyst, improving adsorption efficiency, but also allows gases of different components to be effectively treated in different layers. The gas passing through the catalyst device has essentially removed ozone and nitrogen oxides, achieving the purification purpose. The nitrogen oxides adsorbed on the catalyst surface can be recycled through a subsequent regeneration process, further enhancing the environmental benefits of the device.

[0056] Specifically, it also includes an automatic lifting unit 108, which includes a motor 601 installed inside the housing 100. The output end of the motor 601 is connected to a transmission wheel 602. A stainless steel wire is provided on the transmission wheel 602. One end of the stainless steel wire is fixed to the transmission wheel 602, and the other end passes through an L-shaped column tube 603, wraps around a pulley 604, and is fixedly connected to the top panel of the housing 100 for connecting and lifting the cold plasma generator 201. One end of the top panel is engaged with a columnar slot plate 607 and can... The cold plasma generator 201 moves up and down along the cylindrical slot plate 607 to maintain its stability. The drive wheel 602 is equipped with a reducer 605 and a rotation sensor 606 for counting. The reducer 605 stops the drive wheel when the motor is paused or turned off. The information from the rotation sensor 606 is transmitted to the control panel 101, where the lifting and lowering travel distance is displayed for easy reading and precise control. The distance between the jet discharge port of the cold plasma generator 201 and the material tray is convenient for processing aquatic products, which are then placed in the material tray. The control panel 101 has a switch button for controlling the motor 601; when activated, it controls the lowering or retraction of the stainless steel wire on the drive wheel 602.

[0057] Specifically, the cold plasma generator 201 includes an electrode 204, a cold plasma jet housing 205, and an air inlet pipe 303. The electrode 204 is disposed inside the cold plasma jet housing 205, and the air inlet pipe 303 is disposed on the cold plasma jet housing 205. The air inlet pipe 303 is connected to an external air pump or air inlet pipe to provide the gas required for cold plasma processing.

[0058] Specifically, the electrode 204 is connected to the cold plasma power supply 202, and the cold plasma processing voltage is controlled by the voltage controller 203. The formed cold plasma is ejected in the form of a jet through the nozzle of the cold plasma jet shell 205 and acts on the aquatic products to be dried.

[0059] Example 2:

[0060] A method for drying aquatic products based on the above-mentioned device, using fresh mussel meat as the material, includes the following specific steps:

[0061] 1) Sterilization pretreatment: Fresh mussel meat to be opened is placed in activated water prepared in a water tank for sterilization pretreatment;

[0062] 2) Sample preparation: Remove the pre-sterilized aquatic products from the water tank, place them on a material tray to drain, and weigh them;

[0063] 3) Turn on the drying equipment: Press the equipment switch button to turn on the machine. The gas circulation system will start working at the same time. Then set the drying temperature to 60℃, humidity to 20%, drying time to 14h, and wind speed to 2.5m / s on the operation panel. After confirming the parameters, the temperature inside the chamber will start to rise. During the heating process, the heat flow will be reused through the gas circulation system to achieve energy saving and environmental protection, thereby achieving the purpose of rapid heating. When the temperature inside the chamber rises to the difference ±1℃, put in the sample from step (2).

[0064] 4) Cold Plasma Treatment: Before drying begins, the materials undergo cold plasma treatment. The distance between the cold plasma jet discharge port and the aquatic products is controlled to 3cm by activating the automatic lifting unit on the panel. After the distance adjustment is complete, the automatic lifting unit is turned off. The air flow rate injected into the air inlet pipe is 8L / min. The cold plasma power supply is turned on, and the cold plasma operating frequency is adjusted to 50kHz. The cold plasma treatment voltage is 100V, the current is 0.5mA, the frequency is 50kHz, and the treatment time is 1min. This completes the cold plasma treatment, which accelerates the heat exchange efficiency and moisture diffusion rate of the aquatic products and effectively reduces the content of spoilage microorganisms on the surface of the aquatic products during the drying process.

[0065] 5) Product drying: After the cold plasma treatment is completed, open the automatic lifting unit cold plasma generator to return to the top position, close the cold plasma working gas inlet valve, and blow the active gas in the chamber into the gas purification device for collection, decomposition and removal through the exhaust fan;

[0066] 6) Sampling and Packaging: After drying is complete, turn off the drying equipment and the cold plasma power supply. Take out the dried aquatic products, place them at room temperature for 3 minutes, cool them to room temperature, and then vacuum pack the products to obtain the dried products.

[0067] Example 3:

[0068] A method for drying aquatic products based on the above-mentioned device, using fresh mussel meat as the material, includes the following specific steps:

[0069] 1) Sterilization pretreatment: Fresh mussel meat to be opened is placed in activated water prepared in a water tank for sterilization pretreatment;

[0070] 2) Sample preparation: Remove the pre-sterilized aquatic products from the water tank, place them on a material tray to drain, and weigh them;

[0071] 3) Turn on the drying equipment: Press the equipment switch button to turn on the machine. The gas circulation system will start working at the same time. Then set the drying temperature to 60℃, humidity to 20%, drying time to 14h, and wind speed to 2.5m / s on the operation panel. After confirming the parameters, the temperature inside the chamber will start to rise. During the heating process, the heat flow will be reused through the gas circulation system to achieve energy saving and environmental protection, thereby achieving the purpose of rapid heating. When the temperature inside the chamber rises to the difference ±1℃, put in the sample from step (2).

[0072] 4) Cold Plasma Treatment: Before drying begins, the materials undergo cold plasma treatment. The distance between the cold plasma jet discharge port and the aquatic products is controlled to 3cm by activating the automatic lifting unit on the panel. After the distance adjustment is complete, the automatic lifting unit is turned off. The air flow rate injected into the air inlet pipe is 8L / min. The cold plasma power supply is turned on, and the cold plasma operating frequency is adjusted to 50kHz. The cold plasma treatment voltage is 100V, the current is 0.5mA, the frequency is 50kHz, and the treatment time is 3min. This completes the cold plasma treatment, which accelerates the heat exchange efficiency and moisture diffusion rate of the aquatic products and effectively reduces the content of spoilage microorganisms on the surface of the aquatic products during the drying process.

[0073] 5) Product drying: After the cold plasma treatment is completed, open the automatic lifting device to return the cold plasma generator to the top position, close the valve of the cold plasma working gas inlet pipe, and blow the active gas in the chamber into the gas purification device for collection, decomposition and removal through the exhaust fan;

[0074] 6) Sampling and Packaging: After drying is complete, turn off the drying equipment and the cold plasma power supply. Take out the dried aquatic products, place them at room temperature for 3 minutes, cool them to room temperature, and then vacuum pack the products to obtain the dried products.

[0075] Example 4:

[0076] A method for drying aquatic products based on the above-mentioned device, using fresh mussel meat as the material, includes the following specific steps:

[0077] 1) Sterilization pretreatment: Fresh mussel meat to be opened is placed in activated water prepared in a water tank for sterilization pretreatment;

[0078] 2) Sample preparation: Remove the pre-sterilized aquatic products from the water tank, place them on a material tray to drain, and weigh them;

[0079] 3) Turn on the drying equipment: Press the equipment switch button to turn on the machine. The gas circulation system will start working at the same time. Then set the drying temperature to 60℃, humidity to 20%, drying time to 14h, and wind speed to 2.5m / s on the operation panel. After confirming the parameters, the temperature inside the chamber will start to rise. During the heating process, the heat flow will be reused through the gas circulation system to achieve energy saving and environmental protection, thereby achieving the purpose of rapid heating. When the temperature inside the chamber rises to the difference ±1℃, put in the sample from step (2).

[0080] 4) Cold Plasma Treatment: Before drying begins, the materials undergo cold plasma treatment. The distance between the cold plasma jet discharge port and the aquatic products is controlled to 3cm by activating the automatic lifting unit on the panel. After the distance adjustment is complete, the automatic lifting unit is turned off. The air flow rate injected into the air inlet pipe is 8L / min. The cold plasma power supply is turned on, and the cold plasma operating frequency is adjusted to 50kHz. The cold plasma treatment voltage is 100V, the current is 0.5mA, the frequency is 50kHz, and the treatment time is 5min. This completes the cold plasma treatment, which accelerates the heat exchange efficiency and moisture diffusion rate of the aquatic products and effectively reduces the content of spoilage microorganisms on the surface of the aquatic products during the drying process.

[0081] 5) Product drying: After the cold plasma treatment is completed, open the automatic lifting device to return the cold plasma generator to the top position, close the valve of the cold plasma working gas inlet pipe, and blow the active gas in the chamber into the gas purification device for collection, decomposition and removal through the exhaust fan;

[0082] 6) Sampling and Packaging: After drying is complete, turn off the drying equipment and the cold plasma power supply. Take out the dried aquatic products, place them at room temperature for 3 minutes, cool them to room temperature, and then vacuum pack the products to obtain the dried products.

[0083] Example 5:

[0084] A method for drying aquatic products based on the above-mentioned device, using fresh mussel meat as the material, includes the following specific steps:

[0085] 1) Sterilization pretreatment: Fresh mussel meat to be opened is placed in activated water prepared in a water tank for sterilization pretreatment;

[0086] 2) Sample preparation: Remove the pre-sterilized aquatic products from the water tank, place them on a material tray to drain, and weigh them;

[0087] 3) Turn on the drying equipment: Press the equipment switch button to turn on the machine. The gas circulation system will start working at the same time. Then set the drying temperature to 60℃, humidity to 20%, drying time to 14h, and wind speed to 2.5m / s on the operation panel. After confirming the parameters, the temperature inside the chamber will start to rise. During the heating process, the heat flow will be reused through the gas circulation system to achieve energy saving and environmental protection, thereby achieving the purpose of rapid heating. When the temperature inside the chamber rises to the difference ±1℃, put in the sample from step (2).

[0088] 4) Product drying: No cold plasma treatment is required; the product is dried directly.

[0089] 5) Sampling and Packaging: After drying is complete, turn off the drying equipment and the cold plasma power supply. Take out the dried aquatic products, place them at room temperature for 3 minutes, cool them to room temperature, and then vacuum pack the products to obtain the dried products.

[0090] The results of the above embodiments 1 to 5 are shown in Table 1 and Figures 4 and 5 below.

[0091] Table 1. Parameters and Equation Test Values ​​for Four Models

[0092] The C model was selected from the test values ​​in Table 1 as being more consistent with the drying kinetics of the aquatic product. Therefore, the drying kinetics curve of the product during the drying process was obtained through model C (Figure 4) and the drying time was calculated by the model (Figure 5).

[0093] Figure 4 shows that different durations of cold plasma treatment alter the moisture ratio of mussels during the heat pump drying process. Example 3 showed the best effect, followed by Example 4, but all were more effective than the untreated mussel group in Example 5. This indicates that changing the treatment time with cold plasma can promote the drying of aquatic products to some extent; however, excessively long treatment times may cause the internal structure of the product to collapse, inhibiting moisture migration. Therefore, this example verifies the beneficial effect of introducing cold plasma to assist in the drying of aquatic products, achieving rapid drying and improving efficiency.

[0094] Therefore, we used the selected model C to calculate the predicted drying endpoint time throughout the process by analyzing the changes in moisture content in each example. Figure 5 shows the differences in the drying endpoint time of cold plasma treatment at different times for each example. The drying efficiency was significantly improved. Model calculations showed that the time required to dry mussels to a moisture content of 15% was reduced by up to 6 hours compared to the untreated group, resulting in an efficiency increase of approximately 35.90%, achieving the goal of rapid drying. (The moisture content of dried mussels is ≤15%, which meets the national standard for dried shellfish products.)

[0095] The results show that, compared with the group that did not undergo cold plasma treatment, the drying efficiency of the cold plasma treatment group in examples 2, 3, and 4 was increased by 22.56%, 35.90%, and 33.33%, respectively. This indicates that the method of the present invention significantly improves the drying rate of aquatic products, effectively reduces energy consumption in the drying process, and avoids damage to the quality of aquatic products caused by excessively long drying time.

[0096] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0097] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0098] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0099] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0100] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0101] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A device for the rapid drying and decontamination of fishery products, comprising a drying apparatus and a cold plasma treatment system, characterized in that, in: The drying equipment includes a housing (100), an operation panel (101), an equipment switch (102), a compressor (103), a heating unit (104), a temperature and humidity sensor (105 / 106), a dehumidification outlet (107), a material tray (109), an automatic weighing device (110), and a dehumidifier (111). The operation panel (101) and the equipment switch (102) are respectively located on the front of the outer wall of the housing (100) and are used to set drying parameters and start and stop the drying equipment. The compressor (103), heating unit (104), temperature and humidity sensor (105 / 106), dehumidification outlet (107), material tray (109), automatic weighing device (110), and dehumidifier (111) are located in the housing. The inner cavity of the body (100); the compressor (103) and the dehumidifier (111) are respectively located at the bottom of the inner cavity of the body (100), and a heating unit (104) is provided above the compressor, and the compressor (103) is connected to the heating unit (104); a dehumidifier (111) is provided with a dehumidification port (107) at the top; the dehumidifier (111); the temperature and humidity sensors (105 / 106) are connected, and an automatic weighing device (110) is provided at the bottom of the material tray (109) to record the weight change of aquatic products in real time during the drying process; an air inlet (304) is provided on the lower right side of the body (100), and the air inlet (304) is connected to the compressor (103); The cold plasma processing system includes a cold plasma generator (201), a cold plasma power supply (202), and a voltage controller (203). The cold plasma generator (201) is installed on the top panel of the inner cavity of the housing (100) and is located above the material tray (109). The material tray (109) is directly opposite the jet discharge port of the cold plasma generator (201). The cold plasma generator (201) is connected to the cold plasma power supply (202) and the voltage controller (203) respectively.

2. The device for quick drying and bacteria-reducing pretreatment of aquatic products according to claim 1, characterized in that, It also includes an activation gas recovery and recycling system, which includes an air outlet (301), a blower (302), an air inlet pipe (303), an air inlet (304), an exhaust pipe (305), an exhaust fan (306), a return air duct (307), an exhaust pipe (308), an ozone decomposition device (401), a nitrogen and oxygen absorption device (402), and an external water tank (501). The heating unit (104) has an air outlet (301) on the side facing the material tray (109). The blower (302) is installed in the inner cavity of the box (100), and the air outlet (301) corresponds to the installation position of the blower (302). The ozone decomposition device (401) and the nitrogen and oxygen absorption device (402) are respectively located below the inner cavity of the box (100). An exhaust pipe (305) is provided above the ozone decomposition device (401) and the nitrogen and oxygen absorption device (402). The exhaust pipe (305) is provided with two exhaust pipes (308). One exhaust pipe (308) is connected to the ozone decomposition device (401) and the nitrogen and oxygen absorption device (402). The nitrogen and oxygen absorption device (402) is connected to the compressor (103) through the return air duct (307). The return air duct (307) is used to recover the hot airflow of the drying process for recycling, so as to realize the recycling of heat. The exhaust pipe is connected to the exhaust pipe (308) through the exhaust fan, which is used to draw the activated gas of the treated cold plasma into the exhaust pipe. The other exhaust pipe (308) is connected to the external water tank (501). The external water tank (501) is located on the left side of the box (100) and is used to collect the active substances generated by the cold plasma in the box (100).

3. The device for quick drying and bacteria-reducing pretreatment of aquatic products according to claim 1, characterized in that, It also includes an automatic lifting unit (108), which includes a motor (601). The motor (601) is installed inside the housing (100). The output end of the motor (601) is connected to a transmission wheel (602). A stainless steel wire is provided on the transmission wheel (602). One end of the stainless steel wire is fixed to the transmission wheel (602), and the other end passes through an L-shaped column tube (603) and passes around a certain pulley (604). The other end is fixedly connected to the top panel of the housing (100) for connecting and lifting the cold plasma generator (201). One end of the top panel is engaged on a columnar slot plate (607) and can move up and down along the columnar slot plate (607). To maintain the stability of the cold plasma generator (201); the drive wheel (602) is equipped with a reducer (605) and a rotation sensor (606) for counting. The reducer (605) has the function of stopping the drive wheel when the motor is paused or turned off. The information of the rotation sensor (606) is transmitted to the control panel (101) and the lifting and lowering travel distance can be displayed on the control panel (101) for easy intuitive reading and precise control of the distance between the jet discharge port of the cold plasma generator (201) and the material tray for easy processing of aquatic products; the control panel (101) is equipped with a switch button for controlling the motor (601). When turned on, it can control the stainless steel wire on the drive wheel (602) to be lowered or retracted.

4. The apparatus for rapid drying and sterilization pretreatment of aquatic products according to claim 1, characterized in that, The cold plasma generator (201) includes an electrode (204), a cold plasma jet housing (205), and an air inlet pipe (303). The electrode (204) is disposed inside the cold plasma jet housing (205), and the air inlet pipe (303) is disposed on the cold plasma jet housing (205). The air inlet pipe (303) is connected to an external air pump or air inlet pipe to provide the gas required for cold plasma processing.

5. The device for rapid drying and sterilization pretreatment of aquatic products according to claim 3, characterized in that, The electrode (204) is connected to the cold plasma power supply (202), and the cold plasma processing voltage is controlled by the voltage controller (203). The formed cold plasma is ejected in the form of a jet through the nozzle of the cold plasma jet shell (205) and acts on the aquatic products to be dried.

6. A method for quick drying and decontamination pretreatment of aquatic products, characterized in that, The processing method specifically includes the following steps: S1. Sterilization pretreatment: The aquatic products to be dried are placed in the activated water prepared in the water tank (501) for sterilization pretreatment; S2. Sample preparation: Take the sterilized sample out of the water tank (501), place it on the material tray (109) to drain the water, and weigh it; S3. Turn on the drying equipment: Press the equipment switch button to turn on the machine. The gas circulation system will start working at the same time. Then set the drying parameters on the operation panel. After the parameters are confirmed, the temperature inside the chamber (100) will start to rise. During the heating process, the heat flow will be reused through the gas circulation system to achieve energy saving and environmental protection, thereby achieving the purpose of rapid heating. When the temperature inside the chamber (100) rises to the difference ±1℃, put in the sample from step (2). S4. Cold plasma treatment: During the drying process, the aquatic products can be treated with cold plasma at any time. By activating the automatic lifting unit (108) on the panel, the distance between the jet discharge port of the cold plasma generator (201) and the aquatic products is controlled. After the distance adjustment is completed, the automatic lifting unit is paused or turned off. Air / argon is injected into the air inlet pipe, and the cold plasma power supply is turned on at the same time to treat the aquatic products with cold plasma. S5. Product drying: After the cold plasma treatment is completed, open the automatic lifting unit (108) to return the cold plasma generator to the top position, close the valve of the cold plasma working gas inlet pipe, and blow the active gas in the box into the gas purification device for decomposition and removal in a timely manner through the exhaust fan. S6. Sampling and Packaging: After drying is complete, turn off the drying equipment and cold plasma power supply; take out the dried aquatic products, place them at room temperature for 3 minutes, cool them to room temperature, and then vacuum pack the products to obtain dried products.

7. The method for quick drying and bacteria-reducing pretreatment of aquatic products according to claim 4, wherein the step of drying is performed by using a drying device. In step S3, the drying parameters are specifically set as follows: drying temperature 60℃, humidity 20%, drying time 14h, and wind speed 2.5m / s.

8. The method for quick drying and bacteria-reducing pretreatment of aquatic products according to claim 4, wherein the step of drying is performed by using a drying device. In step S4, the frequency of the cold plasma treatment is 50-65 kHz, and the treatment time is 1-5 min.

9. The method for quick drying and bacteria-reducing pretreatment of aquatic products according to claim 4, wherein, In step S4, the distance between the jet discharge port of the cold plasma generator (201) and the aquatic product is 1-5 cm; the flow rate of air / argon injected into the air inlet pipe is 1.2-1.8 L / min.

10. The method for quick drying and bacteria-reducing pretreatment of aquatic products according to claim 4, characterized in that, In step S5, the moisture content of the aquatic products at different time points during the drying process is recorded by an automatic weighing device to determine the total time required for the drying endpoint. The method for determining the moisture content and calculating the drying endpoint time is as follows: Moisture content was determined based on weight changes. The initial product weight M0 was recorded using an automatic weighing device, and the weights M of the aquatic products at different time points during the drying process were recorded. t and constant weight M e Calculate the moisture content and water content of MC according to formulas (1) and (2): Where MC is the moisture content (g / g), M0 is the initial mass of the product, and M e For constant weight quality of the product, M t For any drying time, MR represents the moisture ratio, MC0 is the initial moisture content of the product, and MC is the product quality. t The moisture content of the product after drying for any time is given by t, where t is the drying time (h). Based on the kinetic model of aquatic product drying, the moisture content and drying endpoint time are calculated by fitting mathematical equations to obtain equation parameters. Four commonly used drying kinetic models, A, B, C, and D, are provided, and the calculation process is as follows: MR = exp(-Kt n ) (A) MR=Kexp(-nt) (B) MR=Kexp(-nt)+K1 (C) MR = 1 + Kt + nt 2 (D) Where K, n and K1 are the unknown parameters (constants) of the model equation, which can be obtained by substituting the drying time t and the measured MR into the model for fitting. After substituting the calculated moisture ratio into the equation and fitting iteratively, the parameters K, n and K1 in the model equations A, B, C and D are calculated to obtain the equation that conforms to the change of moisture ratio of dried aquatic products with drying time t. Therefore, the drying time t required for the drying endpoint can be obtained by combining the obtained parameters and the expected MR value with equation (2).

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