WO2022068035A1 - Continuous-flow magnetically-induced electric field low-temperature sterilization device and method - Google Patents

Abstract

A continuous-flow magnetically-induced electric field low-temperature sterilization device and method, related to the field of light industry. A sterilization processing device in the continuous-flow magnetically-induced electric field low-temperature sterilization device comprises: a magnetic core (201), an excitation coil (202), a magnetic coupling pipe (203), material storage pipes (204), and processing compartments (205). The excitation coil (202) and the magnetic coupling pipe (203) are wrapped on two sides of the magnetic core (201). The excitation coil (202) is connected to a power supply (103). The sterilization processing device is provided with two material storage pipes (204) and two processing compartments (205). The two material storage pipes (203) are in communication with each other via the magnetic coupling pipes (204). The two material storage pipes (204) are in communication correspondingly with the two processing compartments (205). The sterilization temperature of the device falls within the range of the interval of 60-65 °C; the sterilization temperature is low; the sterilization time is less than 1 min; the sterilization time is short; moreover, the need to use a metal electrode is obviated; hence, no electrochemical pollution is incurred; furthermore, because the sterilization temperature is low and the sterilization time is short, when processing food materials, the inherent mouthfeel thereof can be better preserved; and green, low-temperature, and quick sterilization can be implemented with respect to liquid-state food products, condiments, traditional Chinese medicines, and cosmetics.

Description

A continuous flow magnetic induction electric field low temperature sterilization device and method technical field

The invention relates to a continuous flow magnetic induction electric field low-temperature sterilization device and method, belonging to the field of light industry.

Background technique

At present, the traditional thermal sterilization technology in the industry is usually in the form of heat conduction. The heat transfer efficiency of this method is low and the processing time is relatively long, which will cause greater damage to some heat-sensitive nutrients in the material. However, in recent decades, various new in-material sterilization techniques have emerged, such as ohmic heating and microwave heating.

Ohmic heating mainly uses the reciprocating movement of ions in the material to heat by applying a voltage across the material. This method does not require the surface of the object to contact the heat source, but generates heat inside the material, so it can achieve the effect of rapid heating and heating. The effect is also relatively uniform; however, since the electrode plate must be used, and the electrode plate is in direct contact with the material, during the heating process, an electrochemical reaction is easily caused near the electrode plate, resulting in corrosion of the electrode plate, thereby reducing the efficiency and quality of the treatment. Microwave heating technology uses electromagnetic waves for heating, but the heating rate of materials is slower than that of ohmic heating, and the heat distribution is not uniform, so it is not widely used in the field of sterilization.

Further, the ultra-high temperature instantaneous sterilization time is short (usually 10s), but the temperature is high (135-150°C); while the traditional pasteurization temperature is relatively low (60-82°C) but the sterilization time is long (usually 30min); Ultra-high temperature instantaneous sterilization, traditional pasteurization or traditional heat treatment methods will affect the taste of food materials when they are processed. Therefore, in order to achieve green, low-temperature and rapid sterilization of liquid foods, seasonings, traditional Chinese medicines and cosmetics, it is necessary to develop a new type of sterilization device.

SUMMARY OF THE INVENTION

In order to avoid ohmic heat sterilization because the parts close to the electrode plate are prone to cause the electrochemical reaction of the material liquid and the corrosion of the electrode plate, thereby reducing the efficiency and quality of the treatment, and at the same time, it can achieve the effect of low temperature, rapid and continuous sterilization of the material, the present invention provides A continuous flow magnetic induction electric field low-temperature sterilization treatment device includes a sample bottle, a pump, a power supply, a sample bottle and a sterilization treatment device. The sterilization treatment device includes: a magnetic core, an excitation coil, a magnetic coupling tube, a material storage tube and processing chamber, and the range of the ratio of the processing chamber to the cross-sectional area of the magnetic coupling tube is 1:81-1:2; the excitation coil and the magnetic coupling tube are both wound on both sides of the magnetic core, and the excitation coil is connected to the power supply;

The sterilization treatment equipment is provided with two material storage pipes and two treatment chambers, and the two material storage pipes are communicated with each other through a magnetic coupling pipe; the two material storage pipes are correspondingly communicated with the two treatment chambers;

Under the action of the pump, the material to be processed enters the storage tube from the sample bottle, and then flows into the sample bottle through the two processing chambers.

Optionally, the two storage tubes are respectively arranged at the front and rear of the magnetic core, and one of the storage tubes is provided with a sample inlet below it. For the convenience of description, the storage tube with the sample inlet below is called a magnetic The storage tube in front of the core, and the other storage tube is called the storage tube at the rear of the magnetic core; the two storage tubes are connected through a magnetic coupling tube, including:

Both sides of the storage tube in front of the magnetic core are provided with liquid outflow ports, and both sides of the storage tube behind the magnetic core are provided with liquid inflow ports. The magnetic coupling tube on the side is connected.

Optionally, the length of one processing chamber is 10-14 cm, the magnetically induced current density in the processing chamber is 0.5-1 A/cm ² , and the magnetically induced electric field intensity is 100-250 V/cm.

Optionally, the sum of the turns of the excitation coils on both sides of the magnetic core is 4 turns, and the sum of the turns of the magnetic coupling tubes on both sides of the magnetic core is 20-40 turns.

Optionally, the effective magnetic path length l of the magnetic core is 20-100 cm, and the cross-sectional area A is 9-20 cm ² .

Optionally, the magnetic core is made of amorphous nanocrystalline material, the magnetic flux is 0.00027-0.002Wb, the initial magnetic permeability u is 20000-50000, and the magnetic density B is 0.3-1T.

Optionally, when the continuous flow magnetic induction electric field low-temperature sterilization treatment device performs sterilization treatment, the excitation voltage U is 800-1500V, and the frequency f is 60-80kHz.

Optionally, the waveform of the excitation voltage is a double-peak pulse.

Optionally, when the continuous flow magnetic induction electric field low-temperature sterilization treatment device performs sterilization treatment, the treatment speed does not exceed 1 L/min.

Optionally, the processing chamber and the magnetic coupling tube have electrical insulation, and are made of polytetrafluoroethylene, Teflon, quartz, crystal, glass or enamel materials.

The present application also provides a continuous flow magnetic induction electric field low-temperature sterilization method, which adopts the continuous flow magnetic induction electric field low-temperature sterilization device to sterilize a liquid sample with a unit impedance value of 100-500 Ω/cm in a processing chamber; the sterilization treatment process , the liquid sample enters the storage tube from the sample bottle under the action of the pump, and then flows into the sample bottle after being sterilized in the two processing chambers.

Optionally, the flow rate of the liquid sample under the action of the pump does not exceed 1 L/min.

Optionally, during the sterilization treatment, the magnetically induced current density in the treatment chamber is 0.5-1 A/cm ² .

The beneficial effects of the present invention are:

During the treatment process, the magnetic core wound by the excitation coil generates an alternating induced magnetic field by applying a voltage to the excitation coil, and then the magnetic coupling tube filled with materials is subjected to magnetic induction electric field treatment through the alternating induction magnetic field. It has a certain electrical conductivity (0.1-10S/m), so it can quickly sterilize the material under the synergistic effect of the magnetically induced thermal effect (eddy current) and the non-thermal effect (induced electric field) of the alternating magnetic field (the non-thermal effect plays the role of relatively large), the sterilization temperature of the continuous flow magnetic induction electric field low-temperature sterilization device provided by the application is in the range of 60-65 ℃, compared with the ultra-high temperature instantaneous sterilization, the sterilization temperature of the application is low; compared with the traditional pasteurization, the sterilization temperature of the application The sterilization time is less than 1min, and the sterilization time is short; compared with ohmic heat sterilization, no metal electrodes are required, so there is no electrochemical pollution; moreover, due to the low sterilization temperature and the sterilization time period of the method of the present application, when processing food materials, The taste can be better preserved by itself; the method of the present application can realize green, low temperature and rapid sterilization of liquid food, seasoning, traditional Chinese medicine and cosmetics. The sterilization process of the present application essentially uses the non-thermal effect of the magnetic induction electric field to reduce the sterilization temperature, and at the same time uses the thermal effect of the magnetic induction electric field to excite the microorganisms, making them more sensitive to the electric field, so the technical invention has significant advantages.

Compared with the application number 201811607052X previously applied by the inventor, the invention name is "triangle-delta three-phase induction thermal reactor", the application number is 2018116070708, and the invention name is "star-star three-phase induction thermal reactor", The application number is 2018116070695, the invention name is "continuous induction thermal reactor", the application number is 2018116070549, the invention name is "star-delta three-phase induction heat reactor", and the application number is 2018116070515, the invention name is "intermittent thermal reactor" Induction thermal reactor", the present invention adopts the structure of double liquid storage tanks on both sides of the magnetic circuit, which changes the closed loop structure of the liquid raw material in the pipeline, that is, the fluid equivalent circuit is changed, which is conducive to continuous feeding. Incoming and outgoing. This is because it ensures that the partial pressure of the fluid in the T-shaped pipeline connected to the double storage tank is uniform, the raw material is not blocked in the pipeline, and the retention time during processing can be uniform, the flow path is smooth, and the magnetic induction electric field treatment is avoided. The occurrence of local overheating of raw materials. Further, the double liquid storage tank structure adopted in the present invention can further reduce the internal impedance of the fluid food in the pipeline.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a schematic diagram of the overall structure of a continuous flow magnetic induction electric field low-temperature sterilization device provided by an embodiment of the present invention;

2 is a front view of the sterilization treatment equipment in the continuous flow magnetic induction electric field low temperature sterilization device provided by an embodiment of the present invention;

3 is a side view of the sterilization treatment equipment in the continuous flow magnetic induction electric field low temperature sterilization device provided by an embodiment of the present invention;

4 is a top view of the sterilization treatment equipment in the continuous flow magnetic induction electric field low temperature sterilization device provided by an embodiment of the present invention;

5 is a schematic diagram of the size of the magnetic core of the sterilization treatment equipment in the continuous flow magnetic induction electric field low temperature sterilization device provided by an embodiment of the present invention;

6 is a physical diagram of the sterilization treatment equipment in the continuous flow magnetic induction electric field low-temperature sterilization device provided by an embodiment of the present invention;

Among them, the sampling bottle 101, the pump 102, the power supply 103, and the sampling bottle 104; the sterilization treatment equipment includes: a magnetic core 201, an excitation coil 202, a magnetic coupling tube 203, a material storage tube 204, a processing chamber 205, and a liquid outlet tube 206, The tee connection head 207, the fixing plate 208, the base 209; the sterilization treatment equipment includes two storage pipes 204, one of which is provided with a liquid outflow port 210, and the other storage pipe 204 is provided with a liquid inflow port 211;

In Fig. 1-Fig. 4, the arrow is the material flow direction.

FIG. 7 is a comparison chart of sensory evaluation index scores before and after treatment of kiwi fruit juice in different ways in an embodiment of the present invention.

FIG. 8 is a comparison chart of sensory evaluation index scores before and after treatment of fresh milk in different ways in an embodiment of the present invention.

Fig. 9 is a comparison chart of sensory evaluation index scores before and after treatment of whole egg liquid in different ways in an embodiment of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Example 1:

This embodiment provides a continuous flow magnetic induction electric field low temperature sterilization device, see FIG.

As shown in FIG. 2-FIG. 4, the sterilization treatment equipment 200 includes: a magnetic core 201, an excitation coil 202, a magnetic coupling tube 203, a material storage tube 204, a processing chamber 205, a liquid outlet tube 206, a three-way connector 207, Fixing plate 208 and base 209.

As shown in FIG. 2 , in the sterilization treatment equipment 200 , the excitation coil 202 and the magnetic coupling tube 203 are both wound on both sides of the magnetic core 201 . The exciting coil 202 is connected to the power source 103 .

It can be seen from the side view shown in FIG. 3 and the top view shown in FIG. 4 that the sterilization treatment equipment 200 includes two storage tubes 204, which are respectively arranged at the front and rear positions of the magnetic core 201. The two storage tubes 204 are magnetically coupled. The tubes 203 are connected; one of the storage tubes 204 (for the convenience of description, the storage tube 204 is called the storage tube on the front side of the magnetic core) is provided with a liquid outlet 210, and the other storage tube 204 (for the convenience of description, called The storage tube 204 is a storage tube on the rear side of the magnetic core) and is provided with a liquid inflow port 211 . The liquid outflow ports 210 are arranged on both sides of the lower side of the storage tube 204 on the front side of the magnetic core, and the liquid inflow ports 211 are arranged on both sides of the upper side of the storage tube 204 on the rear side of the magnetic core. As shown in FIG. 3 , the liquid on the corresponding side The outflow port 210 communicates with the liquid inflow port 211 through a magnetic coupling tube 203 wound on the corresponding side of the magnetic core.

The two storage tubes 204 are communicated through the magnetic coupling tube 203 , a sample inlet 301 is provided below the storage tube 204 on the front side of the magnetic core 201 , and the material to be treated enters the storage tube on the front side of the magnetic core 201 from the sample inlet. After entering the magnetic coupling tube 203, it flows into the magnetic core 201 from the liquid inflow port 211 provided on the storage tube 204 on the other side. In the storage pipe 204 on the rear side, after the two storage pipes 204 are filled with the liquid to be treated, the liquid to be treated flows out from the upper outlet of the two storage pipes 204 and enters the processing chamber 205, and then passes through the three-way connector. 207 flows out from the liquid outlet pipe 206 and flows into the sample vial 104 from the sample outlet 302 .

The main function of setting two storage tubes 204 is to reduce the partial pressure effect of the material flow path (including the storage tube, the magnetic coupling tube and the processing chamber), because the entire material flow path is equivalent to a circuit, and the guide path (this application The middle guide path is equivalent to the material storage pipe and the magnetic coupling pipe part), the shorter the better, the less the magnetic induction voltage distributed by the guide path part, so that more magnetic induction voltage is distributed to the processing chamber 205 to realize the material processing process .

As can be seen from the figure, a processing chamber 205 is connected to the top of the two storage pipes 204 respectively, and the two processing chambers 205 are connected with the liquid outlet pipe 206 through the tee connector 207. The two processing chambers 205 refer to the two storage pipes respectively. The pipeline between the outlet above 204 and the tee connector 207.

During the processing, the sample inlet 301 and the sample outlet 302 have the same potential, and a magnetically induced current loop exists between the magnetic coupling tube 203 and the processing chamber 205 .

The continuous flow magnetic induction electric field low-temperature sterilization device provided in this embodiment can continuously process materials. In FIG. 1 , the sample bottle 101 and the sample bottle 104 are respectively used to store the materials before and after treatment.

During the processing, the power supply 103 applies a voltage to the excitation coil 202 so that the magnetic core 201 wound by the excitation coil 202 generates an alternating induced magnetic field, and then the magnetic coupling tube 203 filled with materials is subjected to a magnetic induction electric field treatment through the alternating induced magnetic field. Since the material to be treated has a certain electrical conductivity (0.1-10S/m), it can be quickly sterilized under the synergistic effect of the magnetically induced thermal effect (eddy current) and the non-thermal effect (induced electric field) of the alternating magnetic field.

In the sterilization treatment equipment 200, the sum of the turns of the excitation coils on both sides of the magnetic core 201 is 4 turns, and the sum of the turns of the magnetic coupling tubes on both sides of the magnetic core 201 is 20-40 turns. The ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203 ranges from 1:81 to 1:2. A processing chamber 205 has a length of 10-14 cm, a magnetically induced current density of 0.5-1 A/cm ² and a magnetically induced electric field strength of 100-250 V/cm in the processing chamber.

In the sterilization treatment equipment 200, the magnetic core 201 is made of amorphous nanocrystalline material, the effective magnetic path length l of the magnetic core 201 is 20-100 cm, the cross-sectional area A of the magnetic core 201 is 9-20 cm ² , and the magnetic flux of the magnetic core 201 is 0.00027-0.002Wb, the initial magnetic permeability u of the magnetic core is 20000-50000, and the magnetic density B is 0.3-1T. As shown in FIG. 5 , the effective magnetic path length l=(d1+d2)×2.

When the sterilization treatment equipment 200 is used for sterilization treatment, the treatment speed does not exceed 1L/min, the excitation voltage U is 800-1500V, the frequency f is 60-80kHz, and the waveform is a double peak pulse.

During the treatment process, in order to maintain the sterilization temperature within a specific range, a constant temperature jacket is provided on the outer layer of the treatment chamber 205 .

In order to facilitate the removal of the processed materials and the cleaning of the equipment, a liquid outlet 212 is provided below the storage tube 204 on the rear side of the magnetic core. During the processing, the liquid outlet 212 is plugged. After the processing is completed, the liquid outlet 212 can be opened. It is convenient for material removal and cleaning of the material storage pipe 204 .

The fixing plate 208 is used for fixing the excitation coil 202 in the sterilization processing apparatus 200 .

The processing chamber 205 and the magnetic coupling tube 203 are electrically insulating, and can be made of PTFE, Teflon, quartz, crystal, glass or enamel material.

The continuous flow magnetic induction electric field low temperature sterilization device provided by the present application can complete continuous treatment through the treatment chamber 205 at one time. It can be widely used in green, low temperature and rapid sterilization of liquid food, seasoning, traditional Chinese medicine and cosmetics, that is, it can sterilize liquid samples with a unit impedance value of 100-500Ω/cm in the processing chamber.

In order to verify the sterilization effect of the continuous flow magnetic induction electric field low-temperature sterilization device provided by this application and the degree of preservation of the taste of food materials, experiments were carried out with kiwi fruit juice, fresh milk and whole egg liquid to obtain the following examples 2, 3 and implementation. Example 4, during the experiment:

Determination of total colonies: refer to the plate counting method in GB/T 4789.2-2016 "Food Microbiological Inspection Determination of Total Colonies";

Determination of mold and yeast: refer to the plate counting method in GB/T 4789.15-2016 "Food Microbiological Inspection Mold and Yeast Counting".

Embodiment 2

This embodiment provides a sterilization method using the continuous flow magnetic induction electric field low-temperature sterilization device given in the first embodiment, and the material liquid is kiwifruit juice filtered through four layers of gauze as an example.

Specifically, as shown in FIG. 1 , the adopted continuous flow magnetic induction electric field low temperature sterilization device includes: a sample bottle 101 , a pump 102 , a power source 103 , a sample bottle 104 and a sterilization treatment device 200 . The sterilization treatment equipment 200 includes: a magnetic core 201 , an excitation coil 202 , a magnetic coupling tube 203 , a material storage tube 204 , a processing chamber 205 , a liquid outlet tube 206 , a three-way connector 207 , a fixing plate 208 and a base 209 .

The magnetic core 201 is made of amorphous nanocrystalline soft magnetic material.

In this embodiment, the excitation coil 202 is wound on the magnetic core 201, the number of turns of the excitation coil 202 is 4 turns, and a voltage of 1500V is applied to the excitation coil 202 through the power supply 103, and the magnetic flux in the magnetic core 201 is 0.00096Wb.

The magnetic permeability material of the magnetic core 201 is amorphous nanocrystalline as an example, its initial relative permeability is 80000, the magnetic flux density during operation is 0.8T, and the effective magnetic permeability area of the magnetic core 201 is 12 cm ² . The magnetic coupling tube 203 is wound on the magnetic core 201, and the number of turns of the magnetic coupling tube 203 is 20 turns; the magnetic coupling tube 203 and the processing chamber 205 are used as the supports for the continuous flow of the material liquid. At this time, the coupling tube 203 and the processing chamber 205 In the state of communication, the cross-sectional area of the processing chamber 205 is 0.07 cm ² , the cross-sectional area of the magnetic coupling tube 203 is 0.64 cm ² (the ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203 is about 1:9), and the feed liquid is pumped through the pump 103 is passed from the sample bottle 101 to the storage tube 204, and then into the magnetic coupling tube 203.

When the feed liquid (25°C, kiwifruit juice filtered by four layers of gauze) with a conductivity of 4500us/cm measured by the conductivity meter flows through the processing chamber 205, the effective power received by the general electric meter is measured at both ends of the processing chamber 205. The potential difference was 3711V, the length of the treatment chambers 205 on both sides was 24cm, and the electric field strength was 154V/cm. When the feed liquid fills the processing chamber 205, the impedance measured by the impedance analyzer is 4500Ω/10cm, so the induced current in the processing chamber 205 is 0.038A, and the induced current density is 0.54A/cm ² . 301 is submerged in the sample bottle 101, and the sample outlet 302 of the feed liquid is located in the sample bottle 104 for continuous flow processing. When the flow rate of the sample outlet is 0.2ml/min, the residence time of the feed liquid in the processing chamber 205 is 7.7s. Through the infrared thermal imaging test, it is found that the feed liquid at the initial room temperature of 25 ℃ flows in the continuous flow magnetic induction electric field sterilization technology equipment After 1.5 minutes, the temperature of the feed liquid in the processing chamber 205 rose to 63°C.

After sampling, it was found that the total number of colonies in the feed liquid before treatment was 5.7×10 ⁵ , and the number of molds and yeasts was 1.5×10 ⁵ , none of which was detected after treatment, and almost completely killed, achieving the purpose of sterilization.

For the preservation of product taste, the sensory evaluation method was selected in this example to determine, and 10 sensory evaluators (4 males and 6 females) were selected for the sensory evaluation experiment. The appearance, color and aroma of kiwi fruit juice were evaluated, in which appearance and color each accounted for 30 points, and aroma was an important indicator of sensory evaluation, accounting for 40 points. Each indicator is divided into four grades, and the scores from high to low are grade one, grade two, grade three and grade four. The sensory evaluation method is shown in Table 1 below.

Table 1 Sensory evaluation method

The sensory evaluation results are shown in Figure 7 below. The total score of the sensory index after the device provided by the application is significantly higher than that of the traditional heat treatment. In terms of appearance, fresh kiwifruit juice has a low score due to the stratification caused by standing; in terms of color, the heat treatment method is significantly lower than that of the application method, and the treatment method of the application method is closer to fresh juice; in terms of aroma, the heat treatment method has obvious cooking flavor, almost The original smell of kiwifruit cannot be smelled; all in all, the flavor of the kiwifruit juice processed by the method of the present application is closer to that of fresh kiwifruit juice, and its original flavor quality is better preserved.

Embodiment 3

This embodiment provides a sterilization method using the continuous flow magnetic induction electric field low-temperature sterilization device given in the first embodiment, and fresh milk is used as an example for the feed liquid.

Specifically, as shown in FIG. 1 , the adopted continuous flow magnetic induction electric field low temperature sterilization device includes: a sample bottle 101 , a pump 102 , a power source 103 , a sample bottle 104 and a sterilization treatment device 200 . The sterilization treatment equipment 200 includes: a magnetic core 201 , an excitation coil 202 , a magnetic coupling tube 203 , a material storage tube 204 , a processing chamber 205 , a liquid outlet tube 206 , a three-way connector 207 , a fixing plate 208 and a base 209 .

The magnetic core 201 is made of amorphous nanocrystalline soft magnetic material.

In this embodiment, the excitation coil 202 is wound on the magnetic core 201, the number of turns of the excitation coil 202 is 4 turns, and a voltage of 1000V is applied to the excitation coil 202 through a power supply, and the magnetic flux in the magnetic core 201 is 0.00096Wb.

The magnetic permeability material of the magnetic core 201 is taken as an example of amorphous nanocrystalline, its initial relative permeability is 80000, the magnetic flux density during operation is 0.8T, and the effective magnetic permeability area of the magnetic core 201 is 12cm ² ; the magnetic coupling tube 203 Winding on the magnetic core 201, the number of turns of the magnetic coupling tube 203 is 20 turns; the magnetic coupling tube 203 and the processing chamber 205 are used as supports for the continuous flow of the material liquid, and the coupling tube 203 and the processing chamber 205 are in a state of communication at this time. The cross-sectional area of the processing chamber 205 is 0.07 cm ² , the cross-sectional area of the magnetic coupling tube 203 is 0.64 cm ² (the ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203 is about 1:9), and the feed liquid is injected from the sample via the pump 103 The bottle 101 passes into the material storage chamber 204 and then into the magnetic coupling tube 203 .

When the feed liquid (25°C, fresh milk) with a conductivity of 3200us/cm measured by a conductivity meter flows through the treatment chamber 205, the effective potential difference it receives is 2474V, the length of the treatment chambers 205 on both sides is 24cm, and the electric field strength is 103V/ cm, when the material liquid fills the processing chamber 205, the impedance measured by the impedance analyzer is 2800Ω/10cm, so the induced current in the processing chamber 205 is 0.041A, and the induced current density is 0.58A/cm ² . The sample port is located at the bottom of the storage tube 204, the sample inlet 301 of the material liquid is immersed in the sample bottle 101, and the sample outlet 302 of the material liquid is located in the sample bottle 104 for continuous flow processing. When the flow rate of the sample outlet is 0.4ml/min, the residence time of the feed liquid in the processing chamber 205 is 4.2s. Through the infrared thermal imaging test, it is found that the feed liquid at the initial room temperature of 25°C flows in the continuous flow magnetic induction electric field sterilization technology equipment. After 1.5 minutes, the temperature of the feed liquid in the processing chamber 205 rose to 61°C. After sampling, it was found that the total number of colonies of the feed liquid before treatment was 4.9×10 ⁵ , and the number of molds and yeasts was 1.1×10 ⁴ . After induction electric field treatment, none of them were detected, and they were almost completely killed, achieving the purpose of sterilization.

For the preservation of product taste, the sensory evaluation method was selected in this example to determine, and 10 sensory evaluators (4 males and 6 females) were selected for the sensory evaluation experiment. The appearance, color and aroma of fresh milk were evaluated, in which appearance and color each accounted for 30 points, and aroma was an important indicator of sensory evaluation, accounting for 40 points. Each indicator is divided into four grades, and the scores from high to low are grade one, grade two, grade three and grade four. The sensory evaluation method is shown in Table 2 below.

Table 2 Sensory evaluation methods

The sensory evaluation results are shown in Figure 8 below, and the total score of the sensory index of fresh milk after treatment by the device provided in the present application is significantly higher than that of the traditional heat treatment. In terms of appearance and color, the treatment by the method of the present application is not much different from the results of the traditional heat treatment, but in terms of smell, the milk has a greater cooking flavor after the traditional heat treatment, but the treatment by the method of the present application is not much different from that of fresh milk, better retains its flavor quality.

Embodiment 4

This embodiment provides a sterilization method using the continuous flow magnetic induction electric field low-temperature sterilization device given in the first embodiment, and the material liquid takes whole egg liquid as an example.

Specifically, as shown in FIG. 1 , the adopted continuous flow magnetic induction electric field low temperature sterilization device includes: a sample bottle 101 , a pump 102 , a power source 103 , a sample bottle 104 and a sterilization treatment device 200 . The sterilization treatment equipment 200 includes: a magnetic core 201 , an excitation coil 202 , a magnetic coupling tube 203 , a material storage tube 204 , a processing chamber 205 , a liquid outlet tube 206 , a three-way connector 207 , a fixing plate 208 and a base 209 .

The magnetic core 201 is made of amorphous nanocrystalline soft magnetic material.

In this embodiment, the excitation coil 202 is wound on the magnetic core 201, the number of turns of the excitation coil 202 is 4 turns, and a voltage of 900V is applied to the excitation coil 202 through a power supply, and the magnetic flux in the magnetic core 201 is 0.00096Wb.

The magnetic permeability material of the magnetic core 201 is taken as an example of amorphous nanocrystalline, its initial relative permeability is 80000, the magnetic flux density during operation is 0.8T, and the effective magnetic permeability area of the magnetic core 201 is 12cm ² ; the magnetic coupling tube 203 Winding on the magnetic core 201, the number of turns of the magnetic coupling tube 203 is 20 turns; the magnetic coupling tube 203 and the processing chamber 205 are used as supports for the continuous flow of the material liquid, and the coupling tube 203 and the processing chamber 205 are in a state of communication at this time. The cross-sectional area of the processing chamber 205 is 0.07 cm ² , the cross-sectional area of the magnetic coupling tube 203 is 0.64 cm ² (the ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203 is about 1:9), and the feed liquid is injected from the sample via the pump 103 The bottle 101 passes into the material storage chamber 204 and then into the magnetic coupling tube 203 .

When the feed liquid (25°C, whole egg) with a conductivity of 5100ms/cm measured by a conductivity meter flows through the treatment chamber 205, the effective potential difference it receives is 3216V, the length of the treatment chambers 205 on both sides is 24cm, and the electric field strength is 134V/ cm, when the material liquid fills the processing chamber 205, the impedance measured by the impedance analyzer is 4100Ω/10cm, so the induced current in the processing chamber 205 is 0.036A, and the induced current density is 0.51A/cm ² . The sample port 301 is submerged in the sample bottle 101, and the sample outlet 302 of the feed liquid is located in the sample bottle 104 for continuous flow processing. When the flow rate of the sample outlet is 0.4ml/min, the residence time of the feed liquid in the processing chamber 205 is 4.2s. Through the infrared thermal imaging test, it is found that the feed liquid at the initial room temperature of 25°C flows in the continuous flow magnetic induction electric field sterilization technology equipment. After 1.5 minutes, the temperature of the feed liquid in the processing chamber 205 rose to 60°C. After sampling, it was found that the total number of colonies in the feed liquid before treatment was 3.2×10 ⁵ , and the number of molds and yeasts was 1.2×10 ⁴ , none of which was detected after treatment, and almost completely killed, achieving the purpose of sterilization.

It can be seen from the above-mentioned Embodiments 2 to 4 that the continuous flow magnetic induction electric field low-temperature sterilization device provided by the present application can continuously sterilize the materials, and complete the sterilization treatment through the processing chamber at one time; and the sterilization temperature is in the range of 60-65 °C. The sterilization temperature is low; the sterilization time is less than 1min, and the sterilization time is short, which can realize green, low temperature and rapid sterilization of liquid food, seasoning, traditional Chinese medicine and cosmetics.

For the preservation of product taste, the sensory evaluation method is selected in this example to determine. In addition, since the feed liquid in this example is whole egg liquid, the protein in it will solidify under the condition of heating, while the pasteurization method in the existing sterilization method is used for determination. The treatment temperature of the sterilization method is relatively low, so this example is chosen to be compared with the pasteurization method.

In the sensory evaluation experiment, 10 sensory evaluators (4 males and 6 females) were selected to evaluate the color, smell and fluidity of the whole egg liquid after treatment by this method and pasteurization treatment (62°C, 5min) in turn. Mobility accounts for 30 points each, and odor is an important indicator of sensory evaluation, accounting for 40 points. Each indicator is divided into three grades, and the scores from high to low are grade one, grade two, grade three and grade three. The sensory evaluation method is shown in Table 3 below.

Table 3 Sensory evaluation methods

The sensory evaluation results are shown in Figure 9 below. The difference in the sensory quality of the whole egg liquid with different treatment methods is small, and the difference in color and luster before and after treatment is not very large, but the fluidity and odor after treatment are obviously different from those in the fresh group, because the treatment method of the present application is different from the fresh group. The temperature of pasteurization treatment method is almost the same, and the protein content of whole egg liquid is high, which is easy to be heat denatured, so the fluidity is almost reduced, and the difference between the two is not big. In terms of smell, pasteurization treatment time is longer. , the degree of ripening of the egg liquid is higher, and the ripening taste is heavier. Generally speaking, the sensory flavor quality of the method of the present application is also better than that of the pasteurization treatment.

Comparative Example 1

This control example also takes the kiwifruit juice filtered by four layers of gauze as an example. It can be seen from the first embodiment that the continuous flow magnetic induction electric field low-temperature sterilization device provided by the present application is provided with two storage pipes 204 mainly to reduce the partial pressure effect of the material flow path (including the storage pipe, the magnetic coupling pipe and the processing chamber). Because the flow path of the entire material is equivalent to a circuit, the shorter the guide path (in this application, the guide path is equivalent to the material storage tube and the magnetic coupling tube part), the better, so that the magnetic induction voltage distributed by the guide path part is less, so More magnetic induction voltage is distributed to the processing chamber 205 to realize the processing of the material. In order to distribute more magnetically induced voltages to the processing chamber 205, and at the same time make the current density and electric field strength reach the processing threshold value of the thermal effect and the non-thermal effect, the present application defines the ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203. 1:81-1:2.

In order to further verify the influence of the ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203 on the processing effect of the present application, a control experiment was conducted:

The difference between the control experiment and the first embodiment lies in the ratio of the cross-sectional area of the treatment chamber 205 to the magnetic coupling tube 203 in the continuous flow magnetic induction electric field low-temperature sterilization device used, and other device parameters are the same as those of the first embodiment. 4 shows:

Table 4 Experimental results of the ratio of the cross-sectional area of different processing chambers 205 to the magnetic coupling tube 203

In Table 4, the treatment time is the residence time of the feed liquid in the treatment chamber 205, which can be achieved by controlling the flow rate. The remaining proportion of total colonies detected after treatment is the percentage of total colonies detected after treatment and total colonies before treatment. The temperature after treatment is the temperature of the feed liquid after passing through the continuous flow magnetic induction electric field low temperature sterilization device.

As can be seen from Table 4, when the ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203 is not in the range of 1:81-1:2, such as 1:82 and 1:1, the two ends of the processing chamber 205 may be affected. The voltage does not meet the requirements, so that the current density and electric field strength in the processing chamber 205 do not meet the requirements, so that the synergistic sterilization treatment effect of thermal effect and non-thermal effect cannot be achieved. When the ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203 is 1:82, in order to achieve the purpose of sterilization, the required processing time will be more than 20 minutes, and the sterilization is purely dependent on the thermal effect, which directly leads to the high temperature of the feed liquid ( will be greater than 75°C). Similarly, when the ratio of the cross-sectional area of the processing chamber 205 to the magnetic coupling tube 203 is 1:1, in order to achieve the purpose of sterilization, the required processing time will be more than 60 minutes. The return results in a higher temperature of the feed liquid (will be greater than 90°C).

The ratio of the cross-sectional area of other processing chambers 205 to the magnetic coupling tube 203, such as 1:21, 1:58, 1:5, etc., can achieve better sterilization effect, and the processing time is short and the sterilization temperature is low.

Some steps in the embodiments of the present invention may be implemented by software, and corresponding software programs may be stored in a readable storage medium, such as an optical disk or a hard disk.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection of the present invention. within the range.

Claims (12)

1. A continuous flow magnetic induction electric field low temperature sterilization treatment device, comprising a sample bottle, a pump, a power supply, a sample bottle and a sterilization treatment equipment, characterized in that the sterilization treatment equipment includes: a magnetic core, an excitation coil, a magnetic coupling tube, a storage The material tube and the processing chamber, and the ratio of the cross-sectional area of the processing chamber to the magnetic coupling tube is in the range of 1:81-1:2; the excitation coil and the magnetic coupling tube are both wound on both sides of the magnetic core, and the excitation coil and the power supply connect;

   The sterilization treatment equipment is provided with two material storage pipes and two treatment chambers, and the two material storage pipes are communicated with each other through a magnetic coupling pipe; the two material storage pipes are correspondingly communicated with the two treatment chambers;

   Under the action of the pump, the material to be processed enters the storage tube from the sample bottle, and then flows into the sample bottle through the two processing chambers.
2. The device according to claim 1, wherein the two storage tubes are respectively arranged at the front and rear positions of the magnetic core, and a sample inlet is provided below one of the storage tubes. The storage tube of the injection port is the storage tube in front of the magnetic core, and the other storage tube is called the storage tube behind the magnetic core; the two storage tubes are connected through a magnetic coupling tube, including:

   Both sides of the storage tube in front of the magnetic core are provided with liquid outflow ports, and both sides of the storage tube behind the magnetic core are provided with liquid inflow ports. The magnetic coupling tube on the side is connected.
3. The device according to claim 1, wherein the length of one processing chamber is 10-14 cm; the magnetically induced current density in the processing chamber is 0.5-1A/cm ² , and the magnetically induced electric field strength is 100-250 V/cm.
4. The device according to claim 1, wherein the sum of the turns of the excitation coils on both sides of the magnetic core is 4 turns, and the sum of the turns of the magnetic coupling tubes on both sides of the magnetic core is 20-40 turns.
5. The device according to claim 1, wherein the effective magnetic path length l of the magnetic core is 20-100 cm, and the cross-sectional area A is 9-20 cm ² .
6. The device according to claim 1, wherein the magnetic core is made of amorphous nanocrystalline material, the magnetic flux is 0.00027-0.002Wb, the initial permeability u is 20000-50000, and the magnetic density B is 0.3-1T.
7. The device according to claim 1, wherein when the continuous flow magnetic induction electric field low-temperature sterilization treatment device performs sterilization treatment, the excitation voltage U is 800-1500V, the waveform is: double peak pulse, and the frequency f is 60-80kHz .
8. The device according to claim 1, characterized in that, when the continuous flow magnetic induction electric field low-temperature sterilization treatment device performs sterilization treatment, the treatment speed does not exceed 1L/min.
9. The device according to claim 1, wherein the processing chamber and the magnetic coupling tube have electrical insulation, and are made of polytetrafluoroethylene, Teflon, quartz, crystal, glass or enamel material.
10. A continuous flow magnetic induction electric field low-temperature sterilization method, characterized in that, the method adopts the continuous flow magnetic induction electric field low-temperature sterilization device according to any one of claims 1-9 to sterilize the sterilization unit resistance value range of 100-500Ω/cm in the treatment chamber. The liquid sample is sterilized; during the sterilization process, the liquid sample enters the storage tube from the sampling bottle under the action of the pump, and then flows into the sampling bottle after being sterilized in the two processing chambers.
11. The method according to claim 10, wherein the flow rate of the liquid sample under the action of the pump does not exceed 1 L/min.
12. The method according to claim 10, wherein during the sterilization treatment, the magnetically induced current density in the treatment chamber is 0.5-1 A/cm ² .

Images