Induction electric field egg liquid sterilization method based on circular magnetic circuit

Abstract

The invention discloses an induction electric field egg liquid sterilization method based on a toroidal magnetic circuit, and belongs to the field of food processing. The present invention preheats the pretreated egg liquid in a certain temperature environment, and after the preheating is completed, the excitation voltage and frequency are adjusted through a sterilization pipeline and a magnetoelectric coupling pipeline, the egg liquid sterilization temperature is maintained and retained for a period of time, and then aseptic filling is performed. The temperature and time required for the sterilization of the whole egg liquid are controlled, and the killing effect on microorganisms is promoted in combination with the electric current action. Compared with the control group using conventional pasteurization or not using electric field treatment, the sterilization rate is increased by 0.9-47.5%, and the foaming property and emulsification are increased by 12.1% and 22.4% respectively. The method of the present invention can significantly improve the sterilization efficiency and sterilization effect of the whole egg liquid, and is also beneficial to the functional characteristics of the whole egg liquid, improves the commodity value of the whole egg liquid, and has industrial application prospects.

Description

Technical Field

[0001] The invention relates to an induction electric field egg liquid sterilization method based on a circular magnetic circuit, and belongs to the field of food processing. Background Art

[0002] Eggs are rich in nutrients, containing protein, fat, minerals and a variety of important vitamins. They are inexpensive and good quality, and are loved by people all over the world. The sialic acid in eggs is a nutritional and health ingredient that can inhibit stomach infection with certain pathogens; the protein content of eggs accounts for 11-13%, which is an excellent source of protein. Yolk immunoglobulin is an antibody protein found in egg yolks and has an antioxidant effect; the total fat content in eggs is 30-33%, including substances such as yolk, cholesterol and lecithin, of which 63% are unsaturated fatty acids, including omega-3 unsaturated fatty acids, which are beneficial to the development of the human nervous system; egg yolks also contain a large amount of lutein, which plays an important role in preventing retinal pigment degeneration.

[0003] At present, more than half of the raw eggs in developed countries such as Europe and the United States are processed into egg products for sale, among which whole egg liquid is the main egg processed product. Whole egg liquid is made by washing, filtering, sterilizing, homogenizing and packaging raw eggs, which can effectively solve the problem of egg transportation difficulties. Sterilization is an indispensable step in the commercialization of whole egg liquid, but the whole egg liquid is rich in protein and the sterilization conditions that can be selected are limited. For example, at high temperatures, the protein components in the egg liquid will coagulate, which greatly affects the sensory properties and nutritional functions of the egg liquid, and even blocks the pipeline and causes sterilization failure. At present, the universal method for sterilizing egg liquid in the world is pasteurization, that is, heating at 58-65.5℃ for 2.5-5min, but under this combination of temperature and time conditions, it is difficult to avoid the denaturation or even coagulation of some proteins, which causes the deterioration of the functional characteristics of the whole egg liquid, and even causes equipment blockage and losses. In addition to pasteurization, ultraviolet treatment is often used to sterilize the outside of whole eggs, but because the eggshell has a shielding effect on ultraviolet rays, it is impossible to sterilize the internal egg liquid. However, irradiation treatment and high-voltage pulse electric field treatment have a series of problems such as small processing volume and high sterilization cost. Ohmic sterilization requires the use of electrodes in direct contact with egg liquid, which is prone to electrode corrosion and even contamination of food raw materials.

[0004] Therefore, in order to fully sterilize the egg liquid without deteriorating its functional properties and improve the commercial value of the whole egg liquid, it is necessary to study a new sterilization method. Summary of the invention

[0005] In view of the above-mentioned defects in the prior art, the present invention provides an induction electric field egg liquid sterilization method based on a ring-shaped magnetic circuit, which can significantly kill microorganisms in the whole egg liquid while maintaining the functional characteristics of the egg liquid.

[0006] The induction electric field egg liquid sterilization method based on the ring-shaped magnetic circuit of the present invention is to preheat the whole egg liquid to "soften" the cell membrane of the microorganisms in the egg liquid, and then sterilize the whole egg liquid by combining a certain temperature, time and induction electric field treatment. In the induction electric field egg liquid sterilization method based on the ring-shaped magnetic circuit, a peristaltic pump is used to stably transport the whole egg liquid to the magnetoelectric coupling pipeline, and the whole egg liquid replaces the secondary coil of the transformer, thereby generating an induced electric field and an induced current under the action of an alternating magnetic field. The effect of the induction electric field egg liquid sterilization method based on the ring-shaped magnetic circuit on the microorganisms in the egg liquid can be divided into two parts: thermal effect and electric effect.

[0007] The induction electric field based on the ring-shaped magnetic circuit is generated by the induction electric field device based on the ring-shaped magnetic circuit, and the induction electric field device based on the ring-shaped magnetic circuit includes: a sample injection bottle, a pump, a sterilization pipeline, a ring-shaped magnetic core and a magnetoelectric coupling pipeline, a sample storage bottle, a power supply device, a condensation device and a circulation device;

[0008] The sample injection bottle is used to store the whole egg liquid to be sterilized, and the sample storage bottle is used to store the whole egg liquid that has been sterilized;

[0009] The pump is used to pump the sample in the injection bottle into the sterilization pipeline and the magnetoelectric coupling pipeline;

[0010] The magnetoelectric coupling pipe is detachably wound around the toroidal magnetic core. The magnetoelectric coupling pipe has two strands, which are wound in opposite directions, that is, they are wound around the toroidal magnetic core clockwise and counterclockwise, or they are wound around the toroidal magnetic core counterclockwise and clockwise respectively.

[0011] The pump is connected to the sample inlet of the sterilization pipeline and the magnetoelectric coupling pipeline to form a three-pronged branch, wherein the first branch is the sterilization pipeline, and the second and third branches are respectively two magnetoelectric coupling pipelines that are wound in opposite directions to each other; the three-pronged branch converges at the sample outlet and is communicated with the sample storage bottle; the sterilization pipeline is located above the annular magnetic core and the magnetoelectric coupling pipeline; the sterilization pipeline is an insulating heat-resistant pipeline made of materials such as polytetrafluoroethylene, PFA, ceramics or glass, and is used for the temperature-raising sterilization treatment of whole egg liquid; the magnetoelectric coupling pipeline is an insulating heat-resistant pipeline made of materials such as polytetrafluoroethylene, PFA, ceramics or glass, and is used to generate a magnetic induction electric field; the material of the annular magnetic core can be selected from permalloy and nanocrystal; the cross section of the annular magnetic core is a rectangle, and the aspect ratio is greater than 0.5;

[0012] The condensing device and the circulating device are used to control the temperature of the magnetic field environment, and the power supply device is used to supply power.

[0013] The magnetic core is in a circular ring shape, has a rectangular cross section, and has an aspect ratio greater than 0.5.

[0014] The method for sterilizing egg liquid using an induced electric field of the present invention comprises the following steps:

[0015] (1) Keep the egg liquid at 45-50°C for 5-10 minutes to achieve the preheating effect;

[0016] After preheating, the fluidity and permeability of bacterial cell membranes in egg liquid changed, affecting the intracellular environment and hindering the function of transmembrane transport proteins and cell surface receptors;

[0017] (2) after preheating is completed, the egg liquid is pumped into the induced electric field device based on the donut-shaped magnetic circuit, a part of the egg liquid is shunted into the magnetoelectric coupling pipeline and stays in the magnetoelectric coupling pipeline, another part flows through the sterilization pipeline and stays in the sterilization pipeline for 15s-1min before flowing into the sample storage bottle from the sample outlet for aseptic filling, the exciting voltage of the induced electric field device based on the donut-shaped magnetic circuit is 100-800V and the frequency is 20-80kHz, and the temperature is 60-67 ℃;

[0018] After being acted upon by high-frequency alternating induced current, the cell membrane of bacteria in the egg liquid is further damaged due to the electroporation effect. When the induced current passes through the conductive egg liquid, it heats up due to the Joule effect. Therefore, under certain conditions, the combination of electrical effect and thermal effect can kill bacteria in a short time.

[0019] Optionally, the egg liquid pretreatment in step (1) refers to washing, cracking, homogenizing and filtering the eggs. The washing may be carried out with warm water at 35-40°C, to which detergent or disinfectant containing effective chlorine may be added. The homogenization may be carried out with a shear emulsifier at a speed of 1000-4000 rpm for 60-120 seconds. The filtration may be carried out with a 20-40 mesh filter or filter cloth.

[0020] Beneficial effects of the present invention:

[0021] The present invention sterilizes the whole egg liquid by the action of induction current, reduces the heating time by combining with the heat action, and improves the functional characteristics of the whole egg liquid product at the same time, so that the foaming property of the whole egg liquid can be increased from 50.4% to 62.5%, which is 12.1% higher than that of the control group not treated with the induction electric field; the emulsification property is increased from 170.4% to 180.4%, which is 10% higher than that of the control group not treated with the induction electric field. The sterilization process of the present invention is essentially to reduce the stability of the bacterial cell membrane by preheating and the electrical effect of the magnetic induction electric field, and at the same time to stimulate the microorganisms by using the thermal effect of the magnetic induction electric field, thereby reducing the sterilization time and improving the sterilization efficiency. Furthermore, compared with conventional pasteurization treatment, the shorter heat treatment has little effect on the functional characteristics of the egg liquid.

[0022] The present invention can effectively affect (soften) the bacterial cell membrane structure by preheating the whole egg liquid, so that the whole egg liquid can be sterilized by staying in the magnetic induction electric field at 60-67° C. for 15 seconds to 1 minute, and the egg liquid will not coagulate.

[0023] The induction electric field device based on the annular magnetic circuit of the present invention uses a magnetic core made of Permalloy or nanocrystalline, and has the advantage of low power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The invention adopts a magnetic induction electric field device based on a toroidal magnetic circuit. In the figure: 201, a sample injection bottle; 202, a peristaltic pump; 203, a toroidal magnetic core and a magnetic-electric coupling pipeline; 204, a sample storage bottle; 205, a power supply device; 206, a condensing device; 207, a circulation device.

[0025] Figure 2 The structure diagram of the toroidal magnetic core and pipeline of the magnetic induction electric field device based on the toroidal magnetic circuit is shown in the figure: 103, the sample inlet; 102, the sterilization pipeline; 101, the sample outlet; 104, the magnetoelectric coupling pipeline; 105, the toroidal magnetic core.

[0026] Figure 3 It is a comparison chart of the sterilization rates in the whole egg liquid obtained after sterilization treatment of the pasteurized control group, Examples 1-4 and Comparative Examples 1-4.

[0027] Figure 4 1 is a comparison chart of the emulsification changes of the pasteurized control group and the whole egg liquid obtained after sterilization treatment of Examples 1-4.

[0028] Figure 5 1 is a comparison chart of the foaming property changes of the pasteurized control group and the whole egg liquid obtained after sterilization treatment of Examples 1-4. DETAILED DESCRIPTION

[0029] The total colony count of the whole egg liquid before and after sterilization was determined in accordance with GB 4789.2-2016, and the sterilization rate was calculated as follows: sterilization rate (%) = (NE) / N*100%; wherein N is the total colony count of the whole egg liquid before sterilization, and E is the total colony count of the whole egg liquid after sterilization.

[0030] Foaming and emulsifying properties determination: The detection method was carried out according to the method in the paper entitled "Effect of pasteurization on the processing performance of whole egg liquid" by Zheng Kai et al., Food Science and Technology. 2020, 45(01).

[0031] The induction electric field device based on the toroidal magnetic circuit used in the following examples is a magnetic induction thermal reactor produced by Indust (Wuxi) Induction Technology Co., Ltd. Figure 1 , Figure 2As shown, the induction electric field device based on the toroidal magnetic circuit includes: a sample injection bottle 201, a peristaltic pump 202, a sterilization pipeline 102, a toroidal magnetic core and a magnetoelectric coupling pipeline 203, a sample storage bottle 204, a power supply device 205, a condensation device 206, and a circulation device 207; the peristaltic pump 202 is used to pump the sample in the sample injection bottle 201 into the sterilization pipeline 102 and the magnetoelectric coupling pipeline 104, and the magnetoelectric coupling pipeline 104 is detachably wrapped around the toroidal magnetic core 105. The sterilized egg liquid flows into the sample storage bottle 204 from the sterilization pipeline 102, the condensation device 206 and the circulation device 207 are used to control the temperature of the magnetic field environment, and the power supply device 205 is used to supply power to the magnetic field. The magnetoelectric coupling pipeline 104 has two strands, and the two strands are wound in opposite directions, that is, they are wound around the toroidal magnetic core 105 clockwise and counterclockwise, or they are wound around the toroidal magnetic core 105 counterclockwise and clockwise. After the peristaltic pump 202 pumps the egg liquid in the sampling bottle 201 into the sampling port 103, a part of the egg liquid is diverted into and stays in the two magneto-electric coupling pipes 104, and the other part flows through the sterilization pipeline 102 and then flows into the sample storage bottle 204 from the sampling port 101. Subsequently, the egg liquid continuously pumped in by the peristaltic pump 202 flows directly into the sample storage bottle 204 through the sterilization pipeline 102 and the sampling port 101.

[0032] Example 1

[0033] Use warm water and detergent to clean the surface of the eggs, dry them under ultraviolet light to remove bacteria on the surface of the eggshell, homogenize them at 3000 rpm for 100 s, and then filter them with a 30-mesh filter to obtain a whole egg liquid sample. Preheat the whole egg liquid to 48°C and keep it warm for 8 minutes.

[0034] Then, open the power supply device of the induced electric field equipment based on the toroidal magnetic circuit, the whole egg liquid is placed in the sample injection bottle and pumped into the sample inlet 103 by the peristaltic pump, a part of the egg liquid shunting enters the magnetoelectric coupling pipeline 104 and stays in the magnetoelectric coupling pipeline 104, another part flows through the sterilization pipeline 102 and flows into the sample storage bottle 204 after staying for 20s in the sterilization pipeline 102, follow-up, the egg liquid that the peristaltic pump 202 continues to pump into then directly flows into the sample storage bottle 204 via the sterilization pipeline 102, the sample outlet 101. The whole egg liquid flows into the sample storage bottle after staying for 20s in the sterilization pipeline 102. The temperature control of the magnetic induction electric field is 65 DEG C, the excitation voltage intensity 400V, and the electric field frequency 50kHz.

[0035] After the egg liquid in the injection bottle is completely sterilized, the power supply is turned off, the magneto-electric coupling pipe 104 is removed, and the egg liquid remaining therein is cleaned.

[0036] The total colony count, foaming property and emulsifying property of the sterilized whole egg liquid in the sample storage bottle were tested. The results showed that the sterilization rate was 99.9%, the foaming property was 62.5% and the emulsifying property was 192.8%.

[0037] Conventional pasteurization was used as the control group: the surface of the eggs was washed with warm water and detergent, dried under ultraviolet light to remove bacteria on the surface of the eggshell, homogenized at 3000rpm for 100s, and then filtered with a 30-mesh filter to obtain a whole egg liquid sample, preheated to 48°C and kept warm for 8min, and then heated at 65°C for 3min for sterilization. The results showed that the sterilization rate of the control group was 99.0%, the foaming property was 50.4%, and the emulsification property was 170.4%.

[0038] The above results show that the sterilization effect of whole egg liquid treated with induction electric field is better, and the foaming and emulsifying properties are improved by 12.1% and 22.4% respectively.

[0039] Example 2

[0040] Use warm water and detergent to clean the surface of the eggs, dry them under ultraviolet light to remove bacteria on the surface of the eggshell, homogenize them at 3000 rpm for 100 s, and then filter them with a 30-mesh filter to obtain a whole egg liquid sample. Preheat the whole egg liquid to 47°C and keep it warm for 8 minutes.

[0041] Then, open the power supply device of the induced electric field equipment based on the toroidal magnetic circuit, the whole egg liquid is placed in the sample injection bottle and pumped into the sample inlet 103 by the peristaltic pump, a part of the egg liquid shunting enters the magnetoelectric coupling pipeline 104 and stays in the magnetoelectric coupling pipeline 104, another part flows through the sterilization pipeline 102 and flows into the sample storage bottle 204 after staying for 20s in the sterilization pipeline 102, follow-up, the egg liquid that the peristaltic pump 202 continues to pump into then directly flows into the sample storage bottle 204 via the sterilization pipeline 102, the sample outlet 101. The whole egg liquid flows into the sample storage bottle after staying for 20s in the sterilization pipeline 102. The temperature of the magnetic induction electric field is controlled to 60 ℃, and the excitation voltage intensity is still 400V, and the electric field frequency is 50kHz.

[0042] After the egg liquid in the injection bottle is completely sterilized, the power supply is turned off, the magneto-electric coupling pipe 104 is removed, and the egg liquid remaining therein is cleaned.

[0043] The sterilized egg liquid in the sample storage bottle was tested, and the results showed that the sterilization rate was 99.2%, the foaming property was 60%, and the emulsification property was 184.1%. Compared with Example 1, each index decreased by 0.7%, 2.5% and 8.7% respectively.

[0044] Example 3

[0045] Use warm water and detergent to clean the surface of the eggs, dry them under ultraviolet light to remove bacteria on the surface of the eggshell, homogenize them at 3000 rpm for 100 s, and then filter them with a 30-mesh filter to obtain a whole egg liquid sample. Preheat the whole egg liquid to 47°C and keep it warm for 8 minutes.

[0046] Then, open the power supply device of the induced electric field equipment based on the toroidal magnetic circuit, the whole egg liquid is placed in the sample injection bottle and pumped into the sample inlet 103 by the peristaltic pump, a part of the egg liquid shunting enters the magnetoelectric coupling pipeline 104 and stays in the magnetoelectric coupling pipeline 104, another part flows through the sterilization pipeline 102 and flows into the sample storage bottle 204 after staying for 20s in the sterilization pipeline 102, follow-up, the egg liquid that the peristaltic pump 202 continues to pump into then directly flows into the sample storage bottle 204 via the sterilization pipeline 102, the sample outlet 101. The whole egg liquid flows into the sample storage bottle after staying for 15s in the sterilization pipeline 102. The temperature of the magnetic induction electric field is 65 DEG C, and the excitation voltage intensity is 400V, and the electric field frequency is 50kHz.

[0047] After the egg liquid in the injection bottle is completely sterilized, the power supply is turned off, the magneto-electric coupling pipe 104 is removed, and the egg liquid remaining therein is cleaned.

[0048] The sterilized egg liquid in the sample storage bottle was tested, and the results showed that the sterilization rate was 99.1%, the foaming property was 61%, and the emulsification property was 174.1%. Compared with Example 1, each index decreased by 0.8%, 1.5% and 18.7% respectively.

[0049] Example 4

[0050] Use warm water and detergent to clean the surface of the eggs, dry them under ultraviolet light to remove bacteria on the surface of the eggshell, homogenize at 3000 rpm for 100 s, and then filter with a 30-mesh filter to obtain a whole egg liquid sample. Preheat the whole egg liquid to 45°C and keep it warm for 5 minutes.

[0051] Then, open the power supply device of the induced electric field equipment based on the toroidal magnetic circuit, the whole egg liquid is placed in the sample injection bottle and pumped into the sample inlet 103 by the peristaltic pump, a part of the egg liquid shunting enters the magnetoelectric coupling pipeline 104 and stays in the magnetoelectric coupling pipeline 104, another part flows through the sterilization pipeline 102 and flows into the sample storage bottle 204 after staying for 20s in the sterilization pipeline 102, follow-up, the egg liquid that the peristaltic pump 202 continues to pump into then directly flows into the sample storage bottle 204 via the sterilization pipeline 102, the sample outlet 101. The whole egg liquid flows into the sample storage bottle after staying for 20s in the sterilization pipeline 102. The temperature control of the magnetic induction electric field is 65 DEG C, and the excitation voltage intensity is still 400V, and the electric field frequency is 50kHz, and the processing time is 20s.

[0052] After the egg liquid in the injection bottle is completely sterilized, the power supply is turned off, the magneto-electric coupling pipe 104 is removed, and the egg liquid remaining therein is cleaned.

[0053] The sterilized egg liquid in the sample storage bottle was tested, and the results showed that the sterilization rate was 99.0%, the foaming property was 56.3%, and the emulsification property was 172.1%; each index decreased by 0.9%, 6.2% and 20.7% respectively compared with Example 1.

[0054] Comparative Example 1

[0055] The eggs were cleaned with warm water and detergent, dried under UV light to remove bacteria on the eggshell surface, homogenized at 3000 rpm for 100 s, and then filtered with a 30-mesh filter to obtain a whole egg liquid sample. No preheating was performed.

[0056] Then, open the power supply device of the induced electric field equipment based on the toroidal magnetic circuit, the whole egg liquid is placed in the sample injection bottle and pumped into the sample inlet 103 by the peristaltic pump, a part of the egg liquid shunting enters the magnetoelectric coupling pipeline 104 and stays in the magnetoelectric coupling pipeline 104, another part flows through the sterilization pipeline 102 and flows into the sample storage bottle 204 after staying for 20s in the sterilization pipeline 102, follow-up, the egg liquid that the peristaltic pump 202 continues to pump into then directly flows into the sample storage bottle 204 via the sterilization pipeline 102, the sample outlet 101. The whole egg liquid flows into the sample storage bottle after staying for 20s in the sterilization pipeline 102. The temperature control of the magnetic induction electric field is 65 DEG C, and the excitation voltage intensity is 400V, and the electric field frequency is 50kHz.

[0057] The results showed that the sterilization rate was 94.1%, which was 5.8% lower than that of Example 1.

[0058] Comparative Example 2

[0059] Use warm water and detergent to clean the surface of the eggs, dry them under ultraviolet light to remove bacteria on the surface of the eggshell, homogenize them at 3000 rpm for 100 s, and then filter them with a 30-mesh filter to obtain a whole egg liquid sample. Preheat the whole egg liquid to 48°C and keep it warm for 8 minutes.

[0060] Then, open the power supply device of the induced electric field equipment based on the toroidal magnetic circuit, the whole egg liquid is placed in the sample injection bottle and pumped into the sample inlet 103 by the peristaltic pump, a part of the egg liquid shunting enters the magnetoelectric coupling pipeline 104 and stays in the magnetoelectric coupling pipeline 104, another part flows through the sterilization pipeline 102 and flows into the sample storage bottle 204 after staying for 20s in the sterilization pipeline 102, follow-up, the egg liquid that the peristaltic pump 202 continues to pump into then directly flows into the sample storage bottle 204 via the sterilization pipeline 102, the sample outlet 101. The whole egg liquid flows into the sample storage bottle after staying for 20s in the sterilization pipeline 102. The temperature control of the magnetic induction electric field is 55 DEG C, the excitation voltage intensity 400V, and the electric field frequency 50kHz.

[0061] After the egg liquid in the injection bottle is completely sterilized, the power supply is turned off, the magneto-electric coupling pipe 104 is removed, and the egg liquid remaining therein is cleaned.

[0062] The sterilized egg liquid in the sample storage bottle was tested, and the results showed that the sterilization rate was 86.4%, which was 13.5% lower than that in Example 1, and the sterilization effect was poor.

[0063] Comparative Example 3

[0064] Use warm water and detergent to clean the surface of the eggs, dry them under ultraviolet light to remove bacteria on the surface of the eggshell, homogenize them at 3000 rpm for 100 s, and then filter them with a 30-mesh filter to obtain a whole egg liquid sample. Preheat the whole egg liquid to 48°C and keep it warm for 8 minutes.

[0065] Then, open the power supply device of the induced electric field equipment based on the toroidal magnetic circuit, the whole egg liquid is placed in the sample injection bottle and pumped into the sample inlet 103 by the peristaltic pump, a part of the egg liquid shunting enters the magnetoelectric coupling pipeline 104 and stays in the magnetoelectric coupling pipeline 104, another part flows through the sterilization pipeline 102 and flows into the sample storage bottle 204 after staying for 20s in the sterilization pipeline 102, follow-up, the egg liquid that the peristaltic pump 202 continues to pump into then directly flows into the sample storage bottle 204 via the sterilization pipeline 102, the sample outlet 101. The whole egg liquid flows into the sample storage bottle after staying for 15s in the sterilization pipeline 102. The temperature control of the magnetic induction electric field is 65 DEG C, the excitation voltage intensity 400V, and the electric field frequency 10kHz.

[0066] After the egg liquid in the injection bottle is completely sterilized, the power supply is turned off, the magneto-electric coupling pipe 104 is removed, and the egg liquid remaining therein is cleaned.

[0067] The sterilized egg liquid in the sample storage bottle was tested, and the results showed that the sterilization rate was 91.4%, which was 8.5% lower than that in Example 1, and the sterilization effect was poor.

[0068] Comparative Example 4

[0069] Use warm water and detergent to clean the surface of the eggs, dry them under ultraviolet light to remove bacteria on the surface of the eggshell, homogenize them at 3000 rpm for 100 s, and then filter them with a 30-mesh filter to obtain a whole egg liquid sample. Preheat the whole egg liquid to 48°C and keep it warm for 8 minutes.

[0070] Then, do not open the power supply device of the induced electric field equipment based on the toroidal magnetic circuit, do not generate magnetic field, the whole egg liquid is placed in the sample injection bottle and pumped into the sample inlet 103 by the peristaltic pump, a part of the egg liquid shunting enters the magneto-electric coupling pipeline 104 and stays in the magneto-electric coupling pipeline 104, another part flows through the sterilization pipeline 102 and flows into the sample storage bottle 204 from the sample outlet 101 after staying for 20s in the sterilization pipeline 102, follow-up, the egg liquid that the peristaltic pump 202 continues to pump into then directly flows into the sample storage bottle 204 via the sterilization pipeline 102, the sample outlet 101. The whole egg liquid flows into the sample storage bottle after staying for 20s in the sterilization pipeline 102.

[0071] The temperature of the induction electric field device based on the annular magnetic circuit is still 65°C, but the excitation voltage intensity is zero and the electric field frequency is zero (ie, no external electric field is applied). The results show that the sterilization rate is 52.4%, which is 47.5% lower than that of Example 1, and the sterilization effect is poor.

[0072] Comparative Example 5

[0073] Use warm water and detergent to clean the surface of the eggs, dry them under ultraviolet light to remove bacteria on the surface of the eggshell, homogenize them at 3000 rpm for 100 s, and then filter them with a 30-mesh filter to obtain a whole egg liquid sample. Preheat the whole egg liquid to 48°C and keep it warm for 8 minutes.

[0074] Specific implementation method The treatment temperature is still 65°C as in Example 1, but only one magnetic-electric coupling pipeline is used and the treatment time is 20s. The results show that the sterilization rate is 76.4%, which is 23.5% lower than that in Example 1, and the sterilization effect is poor.

[0075] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for sterilizing egg liquid using an induction electric field, characterized in that: The induced electric field is generated by an induced electric field device based on a toroidal magnetic circuit, and the induced electric field device based on a toroidal magnetic circuit includes: a sample injection bottle, a pump, a sterilization pipeline, a toroidal magnetic core and a magnetoelectric coupling pipeline, a sample storage bottle, a power supply device, a condensing device and a circulation device; The magnetoelectric coupling pipe is detachably wound around the annular magnetic core. The magnetoelectric coupling pipe has two strands, which are wound in opposite directions, that is, they are wound around the annular magnetic core clockwise and counterclockwise, or they are wound around the annular magnetic core counterclockwise and clockwise respectively. The pump is connected to the sterilization pipeline and the sample inlet of the magnetoelectric coupling pipeline to form a three-branch branch, wherein the first branch is the sterilization pipeline, and the second and third branches are two magnetoelectric coupling pipelines winding in opposite directions; the three-branch branch merges at the sample outlet and is connected to the sample storage bottle; the sterilization pipeline is located above the annular magnetic core and the magnetoelectric coupling pipeline; The method comprises the following steps: (1) Keep the whole egg liquid at 45-50℃ for 5-10 min; (2) The preheated whole egg liquid is pumped into the induction electric field device based on the ring-shaped magnetic circuit. A part of the egg liquid is diverted into the magneto-electric coupling pipe and stays in the magneto-electric coupling pipe, and the other part flows through the sterilization pipe and stays in the sterilization pipe for 15 s-1 min before flowing into the sample storage bottle from the sample outlet for aseptic filling. The excitation voltage of the induction electric field device based on the ring-shaped magnetic circuit is 100-800 V and the frequency is 20-80 kHz, and the temperature is 60-67°C.

2. The method for sterilizing egg liquid using an induction electric field according to claim 1, characterized in that: The excitation voltage was 400 V and the frequency was 50 kHz, and the temperature was 60°C or 65°C.

3. The method for sterilizing egg liquid using an induction electric field according to claim 1, characterized in that: The other part in step (2) flows through the sterilization pipeline and stays in the sterilization pipeline for 15 s-20 s before flowing from the sample outlet into the sample storage bottle for aseptic filling.

4. The method for sterilizing egg liquid using an induction electric field according to claim 1, characterized in that: The sterilization pipeline is an insulating heat-resistant pipeline made of materials such as polytetrafluoroethylene, PFA, ceramics or glass.

5. The method for sterilizing egg liquid using an induction electric field according to claim 1, characterized in that: The magnetoelectric coupling pipe is an insulating heat-resistant pipe made of materials such as polytetrafluoroethylene, PFA, ceramics or glass.

6. The method for sterilizing egg liquid using an induction electric field according to claim 1, characterized in that: The material of the annular magnetic core is Permalloy or nanocrystal; the cross section of the annular magnetic core is rectangular, and the aspect ratio is greater than 0.

5.

7. The method for sterilizing egg liquid using an induction electric field according to claim 1, characterized in that: The whole egg liquid in step (1) is obtained by washing, cracking, homogenizing and filtering eggs.

8. The method for sterilizing egg liquid using an induction electric field according to claim 7, characterized in that: The cleaning is carried out with warm water at 35-40°C, to which detergent or disinfectant containing effective chlorine is added.

9. The method for sterilizing egg liquid using an induction electric field according to claim 7, characterized in that: The homogenization is performed by a shear emulsifier with a rotation speed of 1000-4000 rpm for 60-120 s, and the filtration is performed by a 20-40 mesh filter screen or filter cloth.

10. An induction electric field device based on a toroidal magnetic circuit for use in the method according to any one of claims 1 to 9, characterized in that: include: A sample injection bottle, a pump, a sterilization pipeline, a toroidal magnetic core and a magnetoelectric coupling pipeline, a sample storage bottle, a power supply device, a condensing device and a circulation device; the magnetoelectric coupling pipeline is detachably wrapped around the toroidal magnetic core, and the magnetoelectric coupling pipeline has two strands, which are wound in opposite directions, that is, they are wound around the toroidal magnetic core clockwise and counterclockwise respectively, or they are wound around the toroidal magnetic core counterclockwise and clockwise respectively; A three-branch road is formed by connecting the pump with the sterilization pipeline and the sample inlet of the magneto-electric coupling pipeline, wherein the first branch road is the sterilization pipeline, and the second and third branches are two magneto-electric coupling pipelines winding in opposite directions; the three-branch road converges at the sample outlet and is connected to the sample storage bottle; the sterilization pipeline is located above the annular magnetic core and the magneto-electric coupling pipeline.

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