Radio frequency sterilization device for food

Abstract

A radio frequency sterilization device for food, comprising: a radio frequency assembly, wherein a first accommodating space is formed in the radio frequency assembly, the radio frequency assembly is configured to generate an electric field in the first accommodating space, and the electric field is used for sterilization; a constant-temperature box (7), located on one side of the radio frequency assembly, wherein a second accommodating space is formed in the constant-temperature box (7); and a spiral pipeline structure (12), comprising a feeding port (13) and a discharge port (8), wherein the feeding port (13) is used for allowing semi-solid food to be sterilized to enter, the spiral pipeline structure (12) comprises at least two pipeline layers arranged in parallel, the two pipeline layers are bent and communicated, one part of each pipeline layer is arranged in the first accommodating space, and the other part is arranged in the second accommodating space, and said semi-solid food entering from the feeding port (13) is sequentially sterilized, heated, and sterilized, or is sequentially heated, sterilized, and heated, and then reaches the discharge port (8), so that the temperature uniformity of said semi-solid food in the radio frequency sterilization process is kept.

Description

A food radio frequency sterilization device

[0001] Cross-references

[0002] This application claims priority to Chinese application No. 202310978250.1 filed on August 4, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of food production technology, and in particular to a food radio frequency sterilization device. Background Art

[0004] With the continuous advancement of technology and the improvement of people's living standards, people's demands for food safety and nutritional value are becoming increasingly stringent. To ensure food quality and extend shelf life, sterilization is an essential step in all food processing processes. Industrial sterilization methods are generally divided into two categories: thermal sterilization and non-thermal sterilization. Among them, radio frequency (RF) thermal sterilization, as a relatively new thermal sterilization method, is considered one of the most promising sterilization technologies in the food industry.

[0005] Pasteurization is the preferred sterilization method for semi-solid foods. Radiofrequency (RF), an emerging thermal sterilization technology, is currently a popular method for pasteurization. RF's advantage over traditional pasteurization methods lies in its ability to heat the entire volume of the material, avoiding the temperature gradients that occur during traditional pasteurization. However, a challenge with existing technologies for sterilizing semi-solid foods is the uneven heating and cooling during RF heating.

[0006] Summary of the Invention

[0007] Therefore, the technical problem to be solved by the present application is to overcome the problem of uneven heating and cooling in the radio frequency heating process in the prior art, thereby providing a food radio frequency sterilization device.

[0008] In order to solve the above problems, the present application provides a food radio frequency sterilization device suitable for semi-solid food, comprising:

[0009] A radio frequency component, wherein the radio frequency component is provided with a first accommodation space, and the radio frequency component is adapted to generate an electric field in the first accommodation space, wherein the electric field is adapted to sterilize the semi-solid food to be sterilized;

[0010] A constant temperature box is located on one side of the radio frequency component, and the constant temperature box is provided with a second accommodation space;

[0011] A spiral pipe structure, the spiral pipe structure includes an inlet and an outlet, the inlet is suitable for semi-solid food to be sterilized to enter, the spiral pipe structure includes at least two layers of parallel pipe layers, the two layers of pipe layers are bent and connected, a part of each layer of pipe layer is arranged in the first accommodating space, and the other part is arranged in the second accommodating space for heating the semi-solid food to be sterilized, the semi-solid food to be sterilized entering from the inlet is sequentially sterilized, heated and sterilized, or sequentially heated, sterilized and heated before reaching the outlet, so that the semi-solid food to be sterilized maintains temperature uniformity during the radio frequency sterilization process.

[0012] Optionally, the radio frequency component includes an upper plate and a lower plate, and a first accommodation space is formed between the upper plate and the lower plate.

[0013] Optionally, the upper electrode plate is connected to a radio frequency generator via a cable.

[0014] Optionally, a fixing frame is provided in both the radio frequency component and the constant temperature box, the fixing frame in the radio frequency component is fixedly connected to the lower electrode plate, and the fixing frame is suitable for fixing the pipe layer of the spiral pipe structure.

[0015] Optionally, the bottom of the constant temperature box is connected to a hot air blower, and the hot air blown out from the hot air blower enters the constant temperature box.

[0016] Optionally, the temperature in the constant temperature box ranges from 25°C to 90°C.

[0017] Optionally, a material feeding component is further included, which includes a storage tank and a material feeding piece. The feeding part of the material feeding piece is connected to the storage tank through a pipeline, and the discharging part of the material feeding piece is fixedly connected to the feeding port.

[0018] Optionally, an opening and closing member is provided on the pipeline between the storage tank and the material conveying member.

[0019] Optionally, a temperature measuring component is further included, which includes a temperature display screen and a temperature sensor, and the temperature sensor is arranged in the bending part of the spiral pipe structure in the first accommodating space.

[0020] Optionally, a controller is further included, which is respectively connected to the storage tank, the material feeding part, the temperature display screen, the temperature sensor, the opening and closing part, the radio frequency generator, and the hot air blower circuit.

[0021] The technical solution of this application has the following advantages:

[0022] 1. The food radio frequency sterilization device provided in the present application includes: a radio frequency component, which is provided with a first accommodating space, and an electric field is generated in the first accommodating space, and the electric field is suitable for sterilizing semi-solid food to be sterilized; a constant temperature box, located on one side of the radio frequency component, and the constant temperature box is provided with a second accommodating space; a spiral pipe structure, including an inlet and an outlet, the inlet is suitable for allowing semi-solid food to be sterilized to enter, the spiral pipe structure includes at least two layers of parallel pipe layers, the two layers of pipe layers are bent and connected, a part of each pipe layer is arranged in the first accommodating space, and the other part is arranged in the second accommodating space for heating the semi-solid food to be sterilized, the semi-solid food to be sterilized entering from the inlet undergoes sterilization, heating and sterilization processes in sequence, or heating, sterilization and heating processes in sequence, and finally reaches the outlet. The above-mentioned constant temperature box and spiral tubular structure cooperate with each other to maintain temperature uniformity of the semi-solid food to be sterilized during the radio frequency sterilization process, avoiding the semi-solid food after radio frequency heating being exposed to the outside of the radio frequency component and cooling, thereby solving the problem of heating uniformity.

[0023] 2. The food radio frequency sterilization device provided in this application, the radio frequency component includes an upper electrode plate and a lower electrode plate, a first accommodating space is formed between the upper electrode plate and the lower electrode plate, the upper electrode plate is connected to the radio frequency generator through a cable, and the radio frequency generator forms an electric field between the upper electrode plate and the lower electrode plate.

[0024] 3. The food radio frequency sterilization device provided in this application is provided with a fixing frame in the radio frequency component and the constant temperature box. The fixing frame in the radio frequency component is fixedly connected to the lower electrode plate. The fixing frame is suitable for fixing the pipe of the spiral pipe structure to fix the spiral pipe structure.

[0025] 4. The food radio frequency sterilization device provided in this application has a hot air blower connected to the bottom of the constant temperature box. The hot air blown out from the hot air blower enters the constant temperature box. The temperature range in the constant temperature box is 25-90°C, which is convenient for adjusting the temperature of the constant temperature box to ensure the temperature of the semi-solid food to be sterilized.

[0026] 5. The food radio frequency sterilization device provided in the present application also includes a feeding component, which includes a storage tank and a feeding piece. The feeding part of the feeding piece is connected to the storage tank through a pipeline, and the discharge part of the feeding piece is fixedly connected to the feeding port. An opening and closing part is provided on the pipeline between the storage tank and the feeding piece, and the feeding speed and flow of the storage tank are controlled by the opening and closing part.

[0027] 6. The food radio frequency sterilization device provided in this application, the temperature measurement component includes a temperature display screen and a temperature sensor. The temperature sensor is attached to the bent part of the spiral pipe structure in the first accommodating space, and the temperature sensor senses the temperature of the spiral pipe structure.

[0028] 7. The food radio frequency sterilization device provided in this application also includes a controller, which is respectively connected to the storage tank, material feeding part, temperature display screen, temperature sensor, opening and closing part, radio frequency generator, and hot air blower circuit to realize the regulation of the entire device. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific implementation methods or the description of the prior art. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0030] FIG1 is a schematic structural diagram of a food radio frequency sterilization device provided in an embodiment of the present application;

[0031] FIG2 is a schematic cross-sectional view of a pipeline layer provided in an embodiment of the present application.

[0032] Explanation of the accompanying symbols: 1. Storage tank; 2. Temperature display screen; 3. Vertical pole; 4. Cable; 5. Radio frequency generator; 6. Fixed bracket; 7. Constant temperature box; 8. Discharge port; 9. Hot air blower; 10. Upper electrode plate; 11. Lower electrode plate; 12. Spiral pipe structure; 13. Feed port; 14. Temperature sensor; 15. Feeding piece. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solution of this application in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0034] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0035] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0036] Example 1

[0037] A specific embodiment of the food radio frequency sterilization device as shown in Figures 1 and 2 includes: a radio frequency component, a constant temperature box 7 located on one side of the radio frequency component, and a spiral pipe structure 12, part of which is arranged in the first accommodation space of the radio frequency component and the other part is arranged in the second accommodation space of the constant temperature box 7.

[0038] As shown in Figure 1, the spiral pipe structure 12 includes six parallel pipe layers, with adjacent upper and lower pipe layers connected by bends. It should be noted that the bends between the first and second pipe layers, arranged parallel from bottom to top, are located within the second storage space; the bends between the second and third pipe layers are located within the first storage space; the bends between the third and fourth pipe layers are located within the second storage space; the bends between the fourth and fifth pipe layers are located within the first storage space; and the bends between the fifth and sixth pipe layers are located within the second storage space. Furthermore, adjacent pipe layers are connected by only one bend. Each horizontally arranged pipe layer includes three parallel pipes, and adjacent pipes in the same pipe layer are connected by bends.

[0039] As shown in Figure 1, the RF component includes a rectangular upper plate 10 and a lower plate 11. A first accommodation space is formed between the upper plate 10 and the lower plate 11. A vertical rod 3 with an external thread is provided at the four corners of the upper plate 10 and the lower plate 11. Specifically, the vertical rod 3 is a screw. As shown in Figure 1, the upper plate 10 is connected to the RF generator 5 through a cable 4. In order to fix the spiral pipe structure 12, a fixing frame 6 is provided in the first accommodation space of the RF component, and the fixing frame 6 is fixedly connected to the lower plate 11. Specifically, the upper plate 10 and the lower plate 11 are both made of titanium alloy, and the output power of the RF generator 5 is 13.56, 27.12, and 40.68 MHz.

[0040] Penetration depth (d p ) is defined as the distance (m) from the surface of the dielectric material to the interior where the electromagnetic wave intensity drops to 1 / e (approximately 37%) of the initial value. RF penetration depth and power density between variable spiral pipes: Pv=2πfε0ε″E 2

[0041] Among them, d p is the penetration depth of radio frequency in semi-solid food, c is the speed of light in vacuum, ε′ is the dielectric constant of semi-solid food, ε" is the dielectric loss factor of semi-solid food, f is the radio frequency generated by the radio frequency component; Pv is the power received by the material in the radio frequency field; ε0 is the relative dielectric constant of electromagnetic waves in vacuum; ε" is the dielectric loss factor of the material; E is the electric field strength. The dielectric constant ε" of common semi-solid foods at room temperature (25°C) is roughly in the range of 2 to 3.5, and the dielectric loss factor ε" is 0.3 to 0.4. According to dp The calculation formula is used to calculate that the penetration depth of radio frequency in the spiral pipe structure 12 ranges from 6.26 to 11.03 m, which can effectively sterilize semi-solid food in the spiral pipe structure.

[0042] As shown in Figure 1, a fixed rack 6 is installed in the second storage space of the thermostat 7. It is important to note that the pipes are arranged horizontally, that is, the fixed rack 6 in the first and second storage spaces are at the same height. As shown in Figure 1, the bottom of the thermostat 7 is connected to a hot air blower 9. The hot air blown by the hot air blower 9 enters the thermostat 7. The temperature of the thermostat 7 can be adjusted within the range of 25-90°C.

[0043] As shown in Figure 1, it also includes a feeding assembly, which includes a storage tank 1 and a feeding piece 15. The feeding part of the feeding piece 15 is connected to the storage tank 1 through a pipeline, and the discharge part of the feeding piece 15 is fixedly connected to the feeding port 13. The pipeline between the storage tank 1 and the feeding piece 15 is provided with an opening and closing part. Specifically, the feeding piece 15 is a screw pump, and the flow rate of the semi-solid food extracted by the feeding piece 15 in the pipeline is 0.8-150m 3 It should be noted that an opening and closing member is provided on the pipeline between the storage tank 1 and the material feeding member 15 .

[0044] As shown in Figure 1, a temperature measuring component is also included, which includes a temperature display screen 2 and a temperature sensor 14. The temperature sensor 14 is arranged in the bent portion of the spiral pipe structure 12 in the first accommodation space. Specifically, the temperature sensor 14 is a temperature measuring optical fiber.

[0045] As shown in FIG1 , the system further includes a controller, which is connected to the storage tank 1 , the feeding member 15 , the temperature display screen 2 , the temperature sensor 14 , the opening and closing member, the radio frequency generator 5 , and the hot air blower 9 .

[0046] During the specific implementation process, the controller opens the opening and closing parts and starts the delivery pump. The Dai-flavored dipping sauce in the storage tank 1 is introduced into the feed port 13 through the delivery pump. The Dai-flavored dipping sauce entering from the feed port 13 passes through the first pipe, the second pipe, ... until the discharge port 8 of the sixth pipe. The Dai-flavored dipping sauce undergoes sterilization, heating, sterilization, heating and other processes. The flow rate of the Dai-flavored dipping sauce in the spiral pipe structure 12 is controlled by adjusting the rotation speed of the delivery part 15, and the flow rate is 0.6m / min; the distance between the upper plate 10 and the lower plate 11 is adjusted. The distance is 60 cm, the radio frequency generator 5 is turned on to make the radio frequency output power 6 kW and the radio frequency frequency 27.12 MHz; the temperature sensor 14 feeds back the sensed temperature to the controller in real time, and the controller then displays it on the display screen; the hot air blower 9 is started to keep the temperature in the constant temperature box 7 at 90°C, and the temperature of the Dai-flavored dipping sauce in the pipeline is monitored in real time by the temperature sensor 14. After the Dai-flavored dipping sauce in the pipeline is treated with radio frequency and kept warm by the constant temperature box 7, it is received by the discharge port 8 for subsequent bottling and packaging.

[0047] Example 2

[0048] The controller opens the opening and closing parts and starts the conveying pump. The vegetable puree in the storage tank 1 is introduced into the feed port 13 through the conveying pump. The flow rate of the vegetable puree in the spiral pipe structure 12 is controlled by adjusting the rotation speed of the conveying part 15, and the flow rate is 0.8 m / min; the distance between the upper electrode 10 and the lower electrode 11 is adjusted to 60 cm, and the radio frequency generator 5 is turned on so that the radio frequency output power is 6 kW and the radio frequency frequency is 27.12 MHz; the temperature sensor 14 feeds back the sensed temperature to the controller in real time, and the controller then displays it on the display screen; the hot air blower 9 is started to keep the temperature in the constant temperature box 7 at 90°C, and the temperature of the vegetable puree in the pipeline is monitored in real time by the temperature sensor 14. After the vegetable puree in the pipeline is treated with radio frequency and kept warm by the constant temperature box 7, it is received by the discharge port 8 for subsequent bottling and packaging.

[0049] Example 3

[0050] The controller opens the opening and closing parts and starts the delivery pump. The fruit puree in the storage tank 1 is introduced into the feed port 13 through the delivery pump. The flow rate of the fruit puree in the spiral pipe structure 12 is controlled by adjusting the rotation speed of the delivery member 15, and the flow rate is 0.9 m / min; the distance between the upper electrode plate 10 and the lower electrode plate 11 is adjusted to 60 cm, and the radio frequency generator 5 is turned on so that the radio frequency output power is 6 kW and the radio frequency frequency is 27.12 MHz; the temperature sensor 14 feeds back the sensed temperature to the controller in real time, which is then displayed on the display screen by the controller; the hot air blower 9 is started to maintain the temperature in the constant temperature box 7 at 90°C, and the temperature of the fruit puree in the pipeline is monitored in real time by the temperature sensor 14. After the fruit puree in the pipeline is subjected to radio frequency treatment and kept warm by the constant temperature box 7, it is received by the discharge port 8 for subsequent bottling and packaging.

[0051] As an alternative embodiment, the semi-solid food can first be subjected to a process of heating, sterilization, heating, sterilization, etc.

[0052] As an alternative embodiment, as shown in FIG. 2 , the pipes may have different sizes and cross-sections.

[0053] As an alternative embodiment, the number of pipeline layers can also be 2 layers, 3 layers, 4 layers, 5 layers, 7 layers or even more layers.

[0054] As an alternative implementation, the number of pipelines provided in the same pipeline layer may be 1, 2, 4 or even more.

[0055] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications derived therefrom remain within the scope of protection of this application.

Claims

1. A food radio frequency sterilization device, suitable for semi-solid food, characterized in that: include: A radio frequency component, wherein the radio frequency component is provided with a first accommodation space, and the radio frequency component is suitable for generating an electric field in the first accommodation space, wherein the electric field is suitable for sterilizing semi-solid food to be sterilized; A constant temperature box (7), located on one side of the radio frequency component, wherein the constant temperature box (7) is provided with a second accommodation space; A spiral pipe structure (12), the spiral pipe structure (12) comprising an inlet (13) and an outlet (8), the inlet (13) being suitable for allowing semi-solid food to be sterilized to enter, the spiral pipe structure (12) comprising at least two parallel pipe layers, the two pipe layers being connected by bending, a portion of each pipe layer being arranged in a first accommodating space and another portion being arranged in a second accommodating space for heating the semi-solid food to be sterilized, the semi-solid food to be sterilized entering from the inlet (13) undergoes sterilization, heating and sterilization processes in sequence, or heating, sterilization and heating processes in sequence, before reaching the outlet (8), so that the semi-solid food to be sterilized maintains temperature uniformity during radio frequency sterilization.

2. The food radio frequency sterilization device according to claim 1, characterized in that: The radio frequency component comprises an upper plate (10) and a lower plate (11), and a first accommodation space is formed between the upper plate (10) and the lower plate (11).

3. The food radio frequency sterilization device according to claim 2, characterized in that: The upper electrode plate (10) is connected to a radio frequency generator (5) via a cable (4).

4. The food radio frequency sterilization device according to claim 2, characterized in that: A fixing frame (6) is provided in both the radio frequency component and the constant temperature box (7); the fixing frame (6) in the radio frequency component is fixedly connected to the lower electrode plate (11); and the fixing frame (6) is suitable for fixing the pipeline layer of the spiral pipeline structure (12).

5. The food radio frequency sterilization device according to claim 4, characterized in that: The bottom of the thermostatic box (7) is connected to a hot air blower (9), and the hot air blown out from the hot air blower (9) enters the thermostatic box (7).

6. The food radio frequency sterilization device according to claim 5, characterized in that: The temperature in the thermostatic box (7) ranges from 25°C to 90°C.

7. The food radio frequency sterilization device according to any one of claims 1 to 6, characterized in that: It also includes a material feeding assembly, which includes a material storage tank (1) and a material feeding piece (15), wherein an inlet of the material feeding piece (15) is connected to the material storage tank (1) via a pipeline, and an outlet of the material feeding piece (15) is fixedly connected to an inlet port (13).

8. The food radio frequency sterilization device according to claim 7, characterized in that: An opening and closing member is provided on the pipeline between the material storage tank (1) and the material conveying member (15).

9. The food radio frequency sterilization device according to claim 8, characterized in that: It also includes a temperature measuring component, which includes a temperature display screen (2) and a temperature sensor (14). The temperature sensor (14) is arranged in the bent part of the spiral pipe structure (12) in the first accommodating space.

10. The food radio frequency sterilization device according to claim 9, characterized in that: It also includes a controller, which is connected to the material storage tank (1), the material feeding member (15), the temperature display screen (2), the temperature sensor (14), the opening and closing member, the radio frequency generator (5), and the hot air blower (9) respectively.

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