A zero-additive food seasoning steady-state fresh-keeping processing method and system

Abstract

The application relates to the technical field of food processing, and discloses a zero-addition food seasoning steady-state preservation processing method and system, which comprises the following steps: gradient vacuum low-temperature dehydration and collection of volatile flavor components; high-voltage pulse electric field and ultrasonic wave time sequence cooperative treatment, so that microbial cells are subjected to electroporation and mechanical disintegration; supercritical carbon dioxide treatment, so that oxidative enzymes and proteases are irreversibly inactivated and free oxygen is removed; backfilling of the collected flavor components into materials; dielectric barrier spectrum treatment for application of an alternating electric field, so that free water is converted into bound water, moisture activity is reduced to a second threshold value; and aseptic vacuum sealing and packaging. The system comprises a flavor separation module, a microbial lysis module, an enzyme inactivation and deoxidation module, a flavor backfilling module, a moisture activity regulation module and an aseptic sealing module. The application realizes long-term steady-state preservation of the seasoning under the condition of no addition of chemical preservatives by adopting a full physical processing method.

Description

Technical Field

[0001] This invention relates to the field of food processing technology, specifically to a method and system for the steady-state preservation of additive-free food seasonings. Background Technology

[0002] Seasonings (such as Sichuan peppercorn powder, black pepper powder, and five-spice powder) are highly susceptible to microbial contamination, enzymatic browning, lipid oxidation and rancidity, and loss of volatile aroma components during processing and storage. This leads to deterioration of product flavor, darkening of color, and even safety hazards. To address these issues, traditional processing methods primarily employ a strategy of high-temperature sterilization combined with the addition of chemical preservatives. However, high-temperature treatment severely damages heat-sensitive flavor substances and active ingredients, causing seasonings to lose their original rich aroma and characteristic flavor. Furthermore, the use of chemical preservatives not only alters the clean label attributes of seasonings, but also, with the increasing consumer demand for additive-free, natural, and healthy foods, the market acceptance of seasonings containing preservatives is gradually declining.

[0003] In recent years, the industry has attempted to replace chemical preservatives with single physical sterilization technologies, such as ultra-high pressure sterilization. This technology applies ultra-high pressure to materials within sealed packaging to inactivate microorganisms. However, its equipment costs are extremely high, and it is an intermittent batch process, making it difficult to achieve continuous industrial production. At the same time, ultra-high pressure treatment has limited effectiveness in inactivating residual oxidases and proteases in materials, and enzymatic quality deterioration can still occur during the shelf life. Therefore, how to achieve complete inactivation of microorganisms, complete inactivation of endogenous enzymes, complete preservation of volatile flavors, and precise control of water activity in condiments without adding any chemical preservatives, thereby obtaining condiments with long shelf-life stability, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for the steady-state preservation of additive-free food seasonings, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for the steady-state preservation of additive-free food seasonings, comprising the following steps: S1. Perform gradient vacuum low-temperature dehydration on the seasoning raw materials that have been cleaned and crushed until the moisture content of the raw materials is reduced to the first threshold, and collect the volatile flavor components that escape during the dehydration process simultaneously. S2. Place the dehydrated raw material from step S1 in a high-voltage pulsed electric field treatment chamber and apply a high-voltage pulsed electric field to the raw material to cause electroporation of the cell membrane. Then introduce the raw material into an ultrasonic resonant cavity and use the ultrasonic cavitation effect to cause mechanical disintegration of the cell wall and spore structure of the microorganisms after electroporation. S3. Place the material processed in step S2 into a supercritical carbon dioxide treatment container, inject supercritical carbon dioxide fluid into the container, and use supercritical carbon dioxide to irreversibly inactivate the oxidases and proteases in the material at the molecular structure level, while removing the residual free oxygen in the material. S4. The volatile flavor components collected in step S1 are backfilled into the material processed in step S3, and homogenization and fusion are completed in a closed mixer to obtain a primary seasoning. S5. The primary seasoning obtained in step S4 is transported to the dielectric resistance spectrum processing area. An alternating electric field is applied to the primary seasoning to directionally bind the polar water molecules in the primary seasoning, converting free water into bound water and reducing the water activity to the second threshold. S6. Under sterile conditions, the material that has been treated in step S5 and whose water activity has reached the second threshold is vacuum-sealed and packaged to obtain the finished product.

[0006] As a preferred embodiment of the present invention, the gradient vacuum low-temperature dehydration in step S1 specifically includes: In the initial stage of dehydration, the vacuum level is controlled at -0.02MPa to -0.05MPa and the temperature at 40-50℃, which allows the surface moisture of the raw material to evaporate rapidly and form microporous channels. In the middle stage of dehydration, the vacuum level is controlled at -0.06MPa to -0.08MPa and the temperature at 30-40℃, and the negative pressure gradient forces the deep moisture inside the raw material to migrate to the surface along the microporous channels. In the final stage of dehydration, the vacuum level is controlled below -0.09MPa and the temperature at 20-25℃, and the partial removal of bound water is completed under conditions without thermal damage. The volatile flavor components are collected using a multi-stage gradient condensation trapping method. The first stage condensation temperature is 0°C to -5°C, which is used to retain terpenes and phenols with boiling points above 80°C. The second stage condensation temperature is -10°C to -20°C, which is used to retain low-molecular-weight aldehydes and ketones with boiling points below 80°C and sulfur-containing flavor substances. Step S1 further includes: storing the flavor components in different boiling point ranges separately in separate tanks, and in step S4, backfilling in layers according to the corresponding ratio of the mass of the dehydrated raw material to the original amount of flavor components released, that is, first backfilling the high boiling point flavor components and mixing them, then backfilling the low boiling point flavor components, and simulating the original flavor profile of the raw material.

[0007] As a preferred technical solution of the present invention, in step S2, the pulse intensity of the high-voltage pulse electric field is 20-50kV / cm, the pulse width is 10-30μs, the pulse frequency is 100-500Hz, and the pulse waveform adopts an exponential decay wave or a square wave, so that the microbial cell membrane is subjected to multiple membrane-penetrating blows during the material flow through the processing chamber. After high-voltage pulsed electric field treatment, the material is directly introduced into the ultrasonic resonant cavity within 10 seconds. The ultrasonic resonant cavity operates at a frequency of 20-40 kHz and a sound intensity of 50-100 W / cm². 2 The ultrasonic treatment time is 30-120 seconds, and the ultrasonic waves propagate in the form of longitudinal waves along the material flow direction. The high-voltage pulsed electric field and the ultrasound form a time-series synergy: the high-voltage pulsed electric field first causes electroporation damage to the microbial cell membrane, which instantaneously increases the cell membrane permeability. Subsequently, the ultrasound cavitation effect preferentially causes asymmetric cavitation at the electroporation site, further tearing the cell membrane pores into irreparable ruptures, causing the cell contents to leak out. Step S2 further includes: setting a cell debris filter at the outlet of the ultrasonic resonant cavity, the filter having a mesh diameter of 0.45-1.2 micrometers, for trapping microbial cell wall fragments after disintegration, while allowing seasoning matrix particles to pass through.

[0008] As a preferred embodiment of the present invention, in step S3, the pressure of the supercritical carbon dioxide treatment container is 25-45 MPa, the temperature is 35-50℃, and the treatment time is 15-60 minutes; the ratio of the supercritical carbon dioxide flow rate to the material mass is 0.5-2.0:1, with units of L / min and kg, respectively. Before injecting supercritical carbon dioxide, the treatment container is evacuated to an absolute pressure of less than 1 kPa to remove the original air inside the container. Supercritical carbon dioxide enters the container through a microporous distribution plate at the bottom, with micropores ranging from 10 to 50 μm in diameter. The supercritical carbon dioxide, in the form of microbubbles, travels upwards through the filter media, simultaneously performing three functions: First, supercritical carbon dioxide complexes with metal ions at the active sites of enzyme molecules, causing irreversible renaturation of the enzyme conformation; second, supercritical carbon dioxide dissolves and displaces free oxygen molecules adsorbed between material particles and within cell debris; third, supercritical carbon dioxide carries away short-chain fatty acids and aldehyde-like odor intermediates produced by the enzymatic hydrolysis reaction. Step S3 further includes: drawing supercritical carbon dioxide carrying free oxygen and odorous substances out of the container and then performing depressurization and vaporization to release the odorous substances. The carbon dioxide is then compressed and recycled. At the same time, the material drawn out of the container is maintained under negative pressure for 30-60 seconds to remove residual trace amounts of carbon dioxide.

[0009] As a preferred technical solution of the present invention, the working frequency of the intermediate resistance isolation spectrum processing region in step S5 is 1-100MHz and the field strength is 10-100V / cm. The dielectric resistance spectrum processing zone consists of multiple sets of parallel electrode plates arranged in series along the material conveying direction. The spacing between each set of parallel electrode plates is 5-20mm. The material passes through the gap between the parallel electrode plates in a laminar flow state. The alternating electric field is applied in a frequency sweep mode, that is, it continuously changes from a starting frequency to an ending frequency, with a sweep rate of 0.1-1MHz / s and a sweep period of 10-100 seconds, and the sweep is repeated for 3-10 cycles. During the frequency sweep process, the free water molecules in the compound seasoning undergo dielectric relaxation response under the action of alternating electric field. When the electric field frequency coincides with the inherent orientation polarization frequency of water molecules, the dipole moment of water molecules is oriented and bound, the hydrogen bond network formed between adjacent water molecules is destroyed, and free water is transformed into short-range ordered bound water. Step S5 further includes: setting an online water activity detection probe at the outlet of the dielectric resistance spectrum processing region; when the detected water activity is higher than the second threshold, increasing the processing time by extending the effective energizing path length of the parallel electrode plate until the water activity reaches the standard.

[0010] A zero-additive food seasoning steady-state preservation processing system, used to perform any one of the methods described above, comprising: The flavor separation module is used to receive the pulverized seasoning raw materials, perform gradient vacuum low-temperature dehydration on the raw materials, and separate and capture the volatile flavor components that escape from the raw materials during the dehydration process, outputting dehydrated material with low moisture content and liquid volatile flavor components. The microbial lysis module has its input end connected to the output end of the flavor separation module. It is used to receive dehydrated materials and apply high-voltage pulse electric field and ultrasonic oscillation to the dehydrated materials in sequence, so that the microbial cells and spores in the dehydrated materials undergo electroporation and mechanical disintegration, and output the inactivated materials after inactivation of microorganisms. The enzyme inactivation and deoxygenation module has its input end connected to the output end of the microbial lysis module. It is used to receive inactivated materials and inject supercritical carbon dioxide fluid into the inactivated materials. The supercritical carbon dioxide fluid irreversibly inactivates the enzyme molecules in the inactivated materials and replaces the free oxygen in the materials, outputting stabilized materials and waste carbon dioxide carrying free oxygen. The flavor backfilling module has a first input end connected to the output end of the enzyme inactivation and deoxygenation module and a second input end connected to the output end of the flavor separation module. It is used to receive the stabilized material and volatile flavor components from the flavor separation module, backfill the volatile flavor components into the stabilized material and complete the homogenization and mixing, and output the compound seasoning. The water activity control module has its input end connected to the output end of the flavor backfilling module. It is used to receive compound seasonings and apply an alternating electric field to the compound seasonings. The alternating electric field directionally binds the polar water molecules in the compound seasonings, thereby reducing the water activity of the compound seasonings and outputting basic seasonings with the required water activity. The aseptic sealing module has its input end connected to the output end of the water activity control module. It is used to receive basic seasonings and perform vacuum sealing packaging on the basic seasonings under aseptic conditions, and output finished seasoning packages.

[0011] As a preferred embodiment of the present invention, the flavor separation module contains at least two stages of vacuum belt drying units connected in series and a gradient condensation collection unit connected to the exhaust port of the vacuum belt drying unit. The gradient condensation trapping unit includes a first-stage trapping unit and a second-stage trapping unit. The condensation temperature of the first-stage trapping unit is configured to be 0°C to -5°C and is used to trap high-boiling-point flavor components. The condensation temperature of the second-stage trapping unit is configured to be -10°C to -20°C and is used to trap low-boiling-point flavor components. The flavor separation module also includes a first storage tank and a second storage tank that are respectively connected to the drain ports of the first-stage trap and the second-stage trap. The first storage tank is used to store high-boiling-point flavor components separately, and the second storage tank is used to store low-boiling-point flavor components separately. The flavor backfilling module receives and backfills the two flavor components in the order of first connecting to the outlet of the first storage tank and then connecting to the outlet of the second storage tank.

[0012] As a preferred embodiment of the present invention, the microbial lysis module comprises a high-voltage pulsed electric field treatment chamber and an ultrasonic resonant cavity connected in series. The high-voltage pulse electric field treatment chamber is equipped with parallel plate electrodes, which are used to apply a pulse electric field to the dewatered material flowing through the treatment chamber. The inner wall of the ultrasonic resonant cavity is attached with a piezoelectric ceramic resonator array, which is used to emit ultrasonic waves to the material flowing through the resonant cavity, causing cavitation bubbles to be generated inside the material. The outlet of the ultrasonic resonant cavity is equipped with a cell debris filter screen with a mesh diameter of 0.45-1.2 micrometers, and a material storage tank is connected downstream of the filter screen. The material conveying pipeline between the high-voltage pulse electric field processing chamber and the ultrasonic resonant cavity has a conveying time corresponding to a length that does not exceed 10 seconds.

[0013] As a preferred embodiment of the present invention, the enzyme inactivation and deoxygenation module includes a high-pressure container, a carbon dioxide storage tank connected to the high-pressure container, a gas-liquid separator connected to the outlet of the high-pressure container, and a compression reuse pipeline connected between the gas-liquid separator and the carbon dioxide storage tank. The carbon dioxide storage tank is used to supply supercritical carbon dioxide fluid into the high-pressure vessel. The high-pressure container is equipped with a stirring blade, which is used to agitate the inactivated material inside the high-pressure container. The bottom of the high-pressure vessel is provided with a microporous distribution plate with a pore size of 10-50μm. Supercritical carbon dioxide from the carbon dioxide storage tank enters the high-pressure vessel in the form of microbubbles through the microporous distribution plate. The gas-liquid separator is used to separate the mixed gas of carbon dioxide, free oxygen and odor substances discharged from the high-pressure container. The separated carbon dioxide is returned to the carbon dioxide storage tank through a compression and reuse pipeline. The top of the high-pressure vessel is also connected to a vacuum pump and a vacuum evacuation pipeline, which is used to evacuate the high-pressure vessel to an absolute pressure of less than 1 kPa before injecting supercritical carbon dioxide.

[0014] As a preferred embodiment of the present invention, the water activity regulation module includes at least one set of parallel dielectric barrier electrode plates and a high-frequency power supply connected between the dielectric barrier electrode plates. A material flow channel is formed between the dielectric insulating electrode plates, through which the compound seasonings pass; The high-frequency power supply is used to supply power to the dielectric resistance electrode plate, so that an alternating electric field is formed in the material flow channel. The dielectric barrier electrode plates are arranged in multiple sets in series along the material conveying direction, and the spacing between each set of electrode plates is 5-20mm. The high-frequency power supply has a built-in frequency scanning controller, which is used to control the output frequency of the high-frequency power supply to change continuously from the starting frequency to the ending frequency, forming a sweeping alternating electric field. The outlet of the water activity control module is also equipped with an online water activity detection probe and an electrode plate length adjustment mechanism electrically connected to the detection probe. The electrode plate length adjustment mechanism is used to adjust the processing time by changing the effective path length of the material flowing through the electrode plate according to the water activity value fed back by the detection probe.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention combines gradient vacuum low-temperature dehydration with multi-stage condensation collection and backfilling to complete the dehydration treatment of seasoning raw materials under low-temperature conditions, avoiding the damage of heat-sensitive flavor substances and active ingredients caused by high temperatures. At the same time, the volatile flavor components that escape during dehydration are collected in stages and backfilled in layers according to proportions, so that the aroma profile of the final product highly reproduces the original flavor of the raw materials, solving the problem of serious flavor loss caused by traditional high-temperature processing.

[0016] 2. This invention employs a sequential processing method that combines high-voltage pulsed electric field and ultrasonic cavitation. First, electroporation pores are formed on the microbial cell membrane. Then, the ultrasonic cavitation effect is used to induce asymmetric cavitation at the electroporation pores, irreversibly tearing the cell membrane pores. This achieves complete mechanical disintegration of microbial cells and spores under normal temperature conditions, avoiding the damage to flavor caused by high-temperature sterilization, and eliminating the need to add any chemical antibacterial agents.

[0017] 3. This invention utilizes supercritical carbon dioxide fluid to perform integrated enzyme inactivation and deoxygenation treatment on materials. Supercritical carbon dioxide can penetrate into the interior of material particles and complex with metal ions in the active centers of oxidases and proteases, causing irreversible renaturation of enzyme molecules. At the same time, it efficiently dissolves and replaces the adsorbed free oxygen in the material, fundamentally eliminating the causes of enzymatic browning and lipid oxidative rancidity in condiments during their shelf life.

[0018] 4. This invention applies an alternating electric field to the seasoning through a dielectric resistance spectrum processing region. By using a frequency sweeping mode, the frequency of the alternating electric field coincides with the inherent orientation polarization frequency of free water molecules, thus directionally binding the free water and converting it into bound water. This significantly reduces the water activity of the material, physically disrupts the survival and reproduction environment of microorganisms, and further extends the shelf life of the product.

[0019] 5. The whole-process physical processing method provided by this invention, from dehydration, sterilization, enzyme inactivation, deoxygenation to water activity regulation, does not involve the introduction of any external chemical substances. At the same time, the modules are connected in series to form a complete processing system, realizing continuous and automated production from raw materials to finished products, and has good prospects for industrial application. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall process of a zero-additive food seasoning steady-state preservation processing method according to the present invention; Figure 2 This is a structural framework diagram of a zero-additive food seasoning steady-state preservation processing system according to the present invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0022] like Figure 1 As shown, the present invention provides a method for the steady-state preservation of additive-free food seasonings, comprising the following steps: S1. Perform gradient vacuum low-temperature dehydration on the seasoning raw materials that have been cleaned and crushed until the moisture content of the raw materials is reduced to the first threshold, and collect the volatile flavor components that escape during the dehydration process simultaneously. S2. Place the dehydrated raw material from step S1 in a high-voltage pulsed electric field treatment chamber and apply a high-voltage pulsed electric field to the raw material to cause electroporation of the cell membrane. Then introduce the raw material into an ultrasonic resonant cavity and use the ultrasonic cavitation effect to cause mechanical disintegration of the cell wall and spore structure of the microorganisms after electroporation. S3. Place the material processed in step S2 into a supercritical carbon dioxide treatment container, inject supercritical carbon dioxide fluid into the container, and use supercritical carbon dioxide to irreversibly inactivate the oxidases and proteases in the material at the molecular structure level, while removing the residual free oxygen in the material. S4. The volatile flavor components collected in step S1 are backfilled into the material processed in step S3, and homogenization and fusion are completed in a closed mixer to obtain a primary seasoning. S5. The primary seasoning obtained in step S4 is transported to the dielectric resistance spectrum processing area. An alternating electric field is applied to the primary seasoning to directionally bind the polar water molecules in the primary seasoning, converting free water into bound water and reducing the water activity to the second threshold. S6. Under sterile conditions, the material that has been treated in step S5 and whose water activity has reached the second threshold is vacuum-sealed and packaged to obtain the finished product.

[0023] Furthermore, step S1, gradient vacuum cryogenic dehydration, specifically includes: In the initial stage of dehydration, the vacuum level is controlled at -0.02MPa to -0.05MPa and the temperature at 40-50℃, which allows the surface moisture of the raw material to evaporate rapidly and form microporous channels. In the middle stage of dehydration, the vacuum level is controlled at -0.06MPa to -0.08MPa and the temperature at 30-40℃, and the negative pressure gradient forces the deep moisture inside the raw material to migrate to the surface along the microporous channels. In the final stage of dehydration, the vacuum level is controlled below -0.09MPa and the temperature at 20-25℃, and the partial removal of bound water is completed under conditions without thermal damage. The collection of volatile flavor components adopts multi-stage gradient condensation capture. The first stage condensation temperature is 0℃ to -5℃, which is used to retain terpenes and phenols with boiling points above 80℃. The second stage condensation temperature is -10℃ to -20℃, which is used to retain low molecular weight aldehydes and ketones and sulfur-containing flavor substances with boiling points below 80℃. Step S1 further includes: storing the flavor components in different boiling point ranges separately in separate tanks, and in step S4, backfilling them in layers according to the corresponding ratio of the mass of the dehydrated raw material to the original amount of flavor components released, that is, first backfilling the high boiling point flavor components and mixing them, then backfilling the low boiling point flavor components, and simulating the original flavor profile of the raw material.

[0024] Furthermore, in step S2, the pulse intensity of the high-voltage pulse electric field is 20-50kV / cm, the pulse width is 10-30μs, the pulse frequency is 100-500Hz, and the pulse waveform adopts an exponential decay wave or a square wave, which performs multiple membrane-penetrating blows on the microbial cell membrane during the material flow through the processing chamber. After high-voltage pulsed electric field treatment, the material is directly introduced into the ultrasonic resonant cavity within 10 seconds. The ultrasonic resonant cavity operates at a frequency of 20-40 kHz and a sound intensity of 50-100 W / cm². 2 The ultrasonic treatment time is 30-120 seconds, and the ultrasonic waves propagate in the form of longitudinal waves along the material flow direction. A temporal synergy is formed between the high-voltage pulsed electric field and ultrasound: the high-voltage pulsed electric field first causes electroporation damage to the microbial cell membrane, which instantaneously increases the permeability of the cell membrane. Subsequently, the cavitation effect of ultrasound preferentially causes asymmetric cavitation at the electroporation site, further tearing the cell membrane pores into irreparable ruptures, causing the contents of the cell to leak out. Step S2 further includes: setting a cell debris filter at the outlet of the ultrasonic resonant cavity, the filter having a mesh diameter of 0.45-1.2 micrometers, for trapping disintegrated microbial cell wall fragments while allowing seasoning matrix particles to pass through.

[0025] Furthermore, in step S3, the pressure of the supercritical carbon dioxide treatment container is 25-45 MPa, the temperature is 35-50℃, and the treatment time is 15-60 minutes; the ratio of supercritical carbon dioxide flow rate to material mass is 0.5-2.0:1, with units of L / min and kg, respectively. Before injecting supercritical carbon dioxide, the treatment container is evacuated to an absolute pressure of less than 1 kPa to remove the original air inside the container. Supercritical carbon dioxide enters the container through a microporous distribution plate at the bottom, with micropores ranging from 10 to 50 μm in diameter. The supercritical carbon dioxide, in the form of microbubbles, travels upwards through the filter media, simultaneously performing three functions: First, supercritical carbon dioxide complexes with metal ions at the active sites of enzyme molecules, causing irreversible renaturation of the enzyme conformation; second, supercritical carbon dioxide dissolves and displaces free oxygen molecules adsorbed between material particles and within cell debris; third, supercritical carbon dioxide carries away short-chain fatty acids and aldehyde-like odor intermediates produced by the enzymatic hydrolysis reaction. Step S3 further includes: after the supercritical carbon dioxide carrying free oxygen and odorous substances is taken out of the container, it is depressurized and vaporized to release the odorous substances. The carbon dioxide is compressed and recycled. At the same time, the material after being taken out of the container is maintained under negative pressure for 30-60 seconds to remove residual trace amounts of carbon dioxide.

[0026] Furthermore, in step S5, the operating frequency of the intermediate resistance isolation spectrum processing region is 1-100MHz, and the field strength is 10-100V / cm. The dielectric resistance spectrum processing zone consists of multiple sets of parallel electrode plates arranged in series along the material conveying direction. The spacing between each set of parallel electrode plates is 5-20mm. The material passes through the gap between the parallel electrode plates in a laminar flow state. The alternating electric field is applied in a frequency sweep mode, that is, it continuously changes from a starting frequency to an ending frequency, with a sweep rate of 0.1-1MHz / s and a sweep period of 10-100 seconds, and the sweep is repeated for 3-10 cycles. During the frequency sweep process, the free water molecules in the compound seasoning undergo dielectric relaxation response under the action of alternating electric field. When the electric field frequency coincides with the inherent orientation polarization frequency of water molecules, the dipole moment of water molecules is oriented and bound, the hydrogen bond network formed between adjacent water molecules is destroyed, and free water is transformed into short-range ordered bound water. Step S5 further includes: setting an online water activity detection probe at the outlet of the dielectric resistance spectrum processing area; when the detected water activity is higher than the second threshold, increasing the processing time by extending the effective energizing path length of the parallel electrode plate until the water activity reaches the standard.

[0027] like Figure 2 As shown, the present invention also provides a zero-additive food seasoning steady-state preservation processing system for performing any of the above methods, comprising: The flavor separation module is used to receive the pulverized seasoning raw materials, perform gradient vacuum low-temperature dehydration on the raw materials, and separate and capture the volatile flavor components that escape from the raw materials during the dehydration process, outputting dehydrated material with low moisture content and liquid volatile flavor components. The microbial lysis module has its input end connected to the output end of the flavor separation module. It is used to receive dehydrated materials and apply high-voltage pulse electric field and ultrasonic oscillation to the dehydrated materials in sequence, so that the microbial cells and spores in the dehydrated materials undergo electroporation and mechanical disintegration, and output the inactivated materials after inactivation of microorganisms. The enzyme inactivation and deoxygenation module has its input end connected to the output end of the microbial lysis module. It is used to receive inactivated materials and inject supercritical carbon dioxide fluid into the inactivated materials. The supercritical carbon dioxide fluid irreversibly inactivates the enzyme molecules in the inactivated materials and replaces the free oxygen in the materials, outputting stabilized materials and waste carbon dioxide carrying free oxygen. The flavor backfilling module has a first input end connected to the output end of the enzyme inactivation and deoxygenation module and a second input end connected to the output end of the flavor separation module. It is used to receive the stabilized material and volatile flavor components from the flavor separation module, backfill the volatile flavor components into the stabilized material and complete the homogenization and mixing, and output the compound seasoning. The water activity control module has its input end connected to the output end of the flavor backfilling module. It is used to receive compound seasonings and apply an alternating electric field to the compound seasonings. The alternating electric field directionally binds the polar water molecules in the compound seasonings, thereby reducing the water activity of the compound seasonings and outputting basic seasonings with the required water activity. The aseptic sealing module has its input end connected to the output end of the water activity control module. It is used to receive basic seasonings and perform vacuum sealing packaging on the basic seasonings under aseptic conditions, and output finished seasoning packages.

[0028] Furthermore, the flavor separation module contains at least two stages of vacuum belt drying units connected in series and a gradient condensation trapping unit connected to the exhaust port of the vacuum belt drying unit. The gradient condensation trapping unit includes a first-stage trapping unit and a second-stage trapping unit. The condensation temperature of the first-stage trapping unit is configured to be 0°C to -5°C and is used to trap high-boiling-point flavor components. The condensation temperature of the second-stage trapping unit is configured to be -10°C to -20°C and is used to trap low-boiling-point flavor components. The flavor separation module also includes a first storage tank and a second storage tank that are respectively connected to the drain ports of the first-stage trap and the second-stage trap. The first storage tank is used to store high-boiling-point flavor components separately, and the second storage tank is used to store low-boiling-point flavor components separately. The flavor backfilling module receives and backfills the two flavor components in the order of first connecting to the outlet of the first storage tank and then connecting to the outlet of the second storage tank.

[0029] Furthermore, the microbial lysis module includes a high-voltage pulsed electric field treatment chamber and an ultrasonic resonant cavity connected in series. The high-voltage pulse electric field treatment chamber is equipped with parallel plate electrodes, which are used to apply a pulse electric field to the dewatered material flowing through the treatment chamber. The inner wall of the ultrasonic resonant cavity is attached with a piezoelectric ceramic resonator array, which is used to emit ultrasonic waves to the material flowing through the resonant cavity, causing cavitation bubbles to be generated inside the material. A cell debris filter is installed at the outlet of the ultrasonic resonant cavity. The mesh diameter of the filter is 0.45-1.2 micrometers. A material storage tank is connected downstream of the filter. The material conveying pipeline between the high-voltage pulse electric field processing chamber and the ultrasonic resonant cavity has a conveying time corresponding to a length of no more than 10 seconds.

[0030] Furthermore, the enzyme inactivation and deoxygenation module includes a high-pressure vessel, a carbon dioxide storage tank connected to the high-pressure vessel, a gas-liquid separator connected to the outlet of the high-pressure vessel, and a compression reuse pipeline connected between the gas-liquid separator and the carbon dioxide storage tank. Carbon dioxide storage tanks are used to supply supercritical carbon dioxide fluid into high-pressure containers. The high-pressure vessel is equipped with a stirring blade, which is used to agitate the inactivated material inside the high-pressure vessel. A microporous distribution plate with a pore size of 10-50μm is installed at the bottom of the high-pressure vessel. Supercritical carbon dioxide from the carbon dioxide storage tank enters the high-pressure vessel in the form of microbubbles through the microporous distribution plate. The gas-liquid separator is used to separate the mixture of carbon dioxide, free oxygen, and odorous substances discharged from the high-pressure container. The separated carbon dioxide is returned to the carbon dioxide storage tank through a compression and reuse pipeline. The top of the high-pressure vessel is also connected to a vacuum pump and a vacuum evacuation line, which is used to evacuate the high-pressure vessel to an absolute pressure of less than 1 kPa before injecting supercritical carbon dioxide.

[0031] Furthermore, the water activity regulation module includes at least one set of parallel-arranged dielectric barrier electrode plates and a high-frequency power supply connected between the dielectric barrier electrode plates. A material flow channel is formed between the dielectric electrode plates, through which compound seasonings pass; The high-frequency power supply is used to supply power to the dielectric resistance electrode plate, so that an alternating electric field is formed in the material flow channel; Multiple sets of dielectric electrode plates are arranged in series along the material conveying direction, with a spacing of 5-20mm between each set of electrode plates. The high-frequency power supply has a built-in frequency scanning controller, which is used to control the output frequency of the high-frequency power supply to change continuously from the starting frequency to the ending frequency, forming a sweeping alternating electric field. The outlet of the water activity control module is also equipped with an online water activity detection probe and an electrode plate length adjustment mechanism electrically connected to the detection probe. The electrode plate length adjustment mechanism is used to adjust the processing time by changing the effective path length of the material flowing through the electrode plate according to the water activity value fed back by the detection probe. Example 2

[0032] Based on the content disclosed in Example 1, this embodiment further details the internal working logic of each module and the collaborative actions between modules in the zero-additive food seasoning steady-state preservation processing system.

[0033] Specifically, after the flavor separation module of this embodiment is started, the input pulverized seasoning raw materials are first processed by at least two stages of vacuum belt drying units connected in series. In the first stage vacuum belt drying unit, the vacuum degree is set to -0.03MPa to -0.04MPa and the temperature is set to 42°C to 48°C. This stage lasts for 15 to 25 minutes, causing the surface moisture of the raw materials to vaporize rapidly and form microporous channels connecting the interior of the raw materials. Subsequently, the raw materials enter the second stage vacuum belt drying unit, where the vacuum degree is set to -0.065MPa to -0.075MPa and the temperature is set to 32°C to 38°C. This stage lasts for 30 to 40 minutes. Through the enhanced negative pressure gradient, the moisture deep in the raw materials is forcibly extracted to the surface along the formed microporous channels. During the surface evaporation and dehydration process, the mixed gas of water vapor and volatile flavor components is pumped by a vacuum pump to a gradient condensation and collection unit. The mixed gas first flows through the first-stage collector, which maintains a constant low temperature of -2℃±2℃ to condense high-boiling-point flavor components such as terpenes and phenols with boiling points above 80℃ into liquid and collect them in the first storage tank. The remaining gas that is not condensed enters the second-stage collector, which maintains a constant low temperature of -15℃±3℃ to condense low-molecular-weight aldehydes and ketones with boiling points below 80℃ and sulfur-containing low-boiling-point flavor components into liquid and collect them in the second storage tank. The clean gas after the two-stage collection is discharged from the system. The dehydrated material after the above dehydration treatment has its moisture content precisely controlled within the first threshold range of 8%-12%.

[0034] The dehydrated material is then conveyed to the microbial lysis module. In the high-voltage pulsed electric field treatment chamber of this module, parallel plate electrodes generate exponentially decaying pulse waves with an intensity of 30kV / cm to 40kV / cm, a pulse width of 15μs-25μs, and a frequency of 200Hz-400Hz. The dehydrated material flows through the gap between the electrode plates in a laminar flow state for 5 to 8 seconds. During this process, the microbial cell membrane undergoes multiple electroporation shocks, causing a sudden and dramatic increase in cell membrane permeability. After the material exits the treatment chamber, it is directly introduced into the ultrasonic resonant cavity within 7 seconds. The piezoelectric ceramic oscillator array on the inner wall of the resonant cavity emits at a frequency of 28kHz to 32kHz and a sound intensity of 65W / cm². 2 Up to 80W / cm 2The ultrasonic waves propagate longitudinally along the material flow direction. Due to the structural damage to the microbial cell membrane caused by the high-voltage pulse electric field, the microjets and shock waves generated by the ultrasonic cavitation effect preferentially act on these electroporous pores, resulting in asymmetric cavitation. This irreversibly tears the cell membrane pores into ruptures, causing a large amount of cell contents to leak out, achieving complete mechanical disintegration of microbial cells and spores. The material containing the disintegrated microbial fragments flows through a cell debris filter with a mesh diameter of 0.8μm to 1.0μm at the outlet. This filter traps microbial cell wall fragments larger than 0.8μm, while allowing seasoning matrix particles and leaked cell contents to pass through, thereby achieving effective purification of the inactivated material.

[0035] After purification, the inactivated material enters the enzyme inactivation and deoxygenation module. First, the vacuum pump and vacuum line connected to the top of the high-pressure container are used to evacuate the inside of the high-pressure container to an absolute pressure below 0.5 kPa, completely removing the original air inside the container and preventing residual oxygen from oxidizing the flavor. After evacuation, supercritical carbon dioxide fluid from the carbon dioxide storage tank enters the container evenly in the form of microbubbles through the microporous distribution plate at the bottom of the high-pressure container. The stirring blades inside the high-pressure container slowly agitate the inactivated material at a speed of 10 to 20 revolutions per minute, ensuring that the supercritical carbon dioxide microbubbles are in full contact with the material particles. The supercritical carbon dioxide fluid passes through the filter layer from bottom to top, achieving three functions simultaneously within a processing time of 15 to 45 minutes: First, the strong solubility and low viscosity of supercritical carbon dioxide allow it to penetrate into the interior of the material particles and undergo a complexation reaction with the metal ions in the active centers of oxidases and proteases, causing irreversible renaturation of the secondary and tertiary structures of the enzyme protein, resulting in permanent enzyme inactivation. Secondly, the high diffusion coefficient of supercritical carbon dioxide enables it to efficiently dissolve and replace free oxygen molecules adsorbed in the gaps between material particles and cell debris, reducing the oxygen content inside the material from its original level to below 50 ppm. Thirdly, supercritical carbon dioxide simultaneously dissolves and carries away short-chain fatty acids and aldehyde odor intermediates produced by previous enzymatic reactions or microbial metabolism. The supercritical carbon dioxide carrying free oxygen and odor substances is drawn from the top of the high-pressure vessel and enters the gas-liquid separator. In the gas-liquid separator, the pressure drops to 5 MPa to 8 MPa and the temperature drops to 25°C to 30°C. The carbon dioxide changes from a supercritical state to a gaseous state, while the free oxygen and odor substances precipitate out due to the sharp decrease in solubility. The separated clean gaseous carbon dioxide is recompressed to a supercritical state through the compression and reuse pipeline and returned to the carbon dioxide storage tank for recycling. At the same time, the processed material is discharged from the bottom of the high-pressure vessel and maintained under negative pressure for 40 to 50 seconds to remove trace amounts of residual carbon dioxide adsorbed on the surface of the material.

[0036] The stabilized material, after enzyme inactivation and deoxygenation, is homogenized with high-boiling-point and low-boiling-point flavor components mixed in proportion in the flavor backfilling module. It then enters the water activity control module, where multiple sets of parallel dielectric barrier electrode plates are arranged in series along the material conveying direction, with an inter-set spacing of 10mm to 15mm. The frequency scanning controller built into the high-frequency power supply controls the output frequency to continuously change from a starting frequency of 5MHz to a final frequency of 80MHz, with a sweep rate of 0.2MHz / s to 0.5MHz / s. Based on the sweep rate, the time required to complete one frequency sweep from 5MHz to 80MHz is 150 seconds to 375 seconds. In this embodiment, each complete sweep cycle is set to 180 seconds to 300 seconds, and the sweep is repeated for 3 to 5 cycles. During the frequency sweep, free water molecules in the compound seasoning undergo dielectric relaxation response under the action of an alternating electric field. When the sweep frequency passes through the 15MHz to 25MHz range, this frequency range corresponds to the free water... When the intrinsic polarization frequencies of the molecules coincide, the dipole moments of water molecules are forced to turn and become oriented by the alternating electric field. The original continuous hydrogen bond network between adjacent water molecules is disrupted, and free water is transformed into short-range ordered bound water existing in the form of single or small clusters of water molecules. The water activity of the material decreases from the initial 0.75-0.85 to the second water activity threshold of 0.65. The online water activity detection probe at the outlet of the water activity control module monitors the water activity value of the outlet material in real time. When the detected value is higher than 0.65, the electrode plate length adjustment mechanism electrically connected to the detection probe automatically changes the effective path length of the material flowing through the electrode plate. Specifically, this is achieved by controlling the switching valve group to make the material repeatedly flow through the existing electrode plate gap, which is equivalent to extending the total residence time of the material in the alternating electric field until the outlet water activity drops below 0.65. The qualified basic seasoning finally enters the aseptic sealing module and is vacuum sealed and packaged in a Class 100 laminar flow clean environment, and the finished product is output.

[0037] Taking black pepper produced in Yunnan Province as an example, the technical effects of the black pepper seasoning powder processed using the method of this embodiment can be deduced through the following logic: gradient vacuum low-temperature dehydration avoids the damage of piperine and volatile aroma components caused by high temperature, while multi-stage condensation capture and layered backfilling maximize the reproduction of the original aroma profile; high-voltage pulse electric field and ultrasonic time sequence synergy achieve complete inactivation of microorganisms at room temperature; supercritical carbon dioxide treatment inactivates oxidases and proteases, eliminating enzymatic browning and lipid oxidation rancidity during storage; dielectric barrier spectrum treatment reduces water activity to below 0.65, physically inhibiting the growth environment of residual microorganisms. The result of the above multi-physical field synergy is that, without adding any chemical preservatives, after the product is stored for 6 months under accelerated destructive testing conditions at 37°C, the piperine content retention rate is expected to exceed 92%, the retention rate of the main volatile aroma components is expected to exceed 85%, the total bacterial count is below 100 CFU / g, the peroxide value is below 0.10g / 100g, and the shelf life can reach more than 24 months. Example 3

[0038] This embodiment uses Sichuan peppercorns produced in Sichuan as raw material to verify the specific application of the method and system of the present invention.

[0039] This embodiment uses the same method and steps as Embodiment 1 and the system working logic of Embodiment 2, but the specific process parameters are optimized and adjusted according to the characteristics of the Sichuan pepper raw material.

[0040] Step S1: Perform gradient vacuum low-temperature dehydration on the cleaned and pulverized Sichuan peppercorns (30-50 mesh). Initially, the vacuum is controlled at -0.04 MPa and the temperature at 48°C for 20 minutes, allowing rapid evaporation of moisture from the peppercorn pericarp surface and the formation of microporous channels connecting the oil cells. In the middle stage of dehydration, the vacuum is adjusted to -0.07 MPa and the temperature to 35°C for 35 minutes. The negative pressure gradient forces moisture from inside the peppercorn seeds and deep within the oil cells to migrate and evaporate to the surface along the microporous channels. Finally, in the final stage of dehydration, the vacuum is increased to -0.095 MPa and the temperature to 22°C for 15 minutes. Without compromising the thermal stability of the numbing and aromatic substances in Sichuan pepper, some bound water is removed. The dehydration process involves multi-stage condensation and capture of flavor components: the first stage condensation temperature is -3℃, capturing components with boiling points above 80℃, mainly including terpenoid aroma substances such as β-myrcene, sapinene, and limonene; the second stage condensation temperature is -18℃, capturing components with boiling points below 80℃, mainly including low-molecular-weight oxygenated terpenoid aroma substances such as linalool and linalyl acetate. The captured flavor components are stored in the first and second storage tanks respectively for later use. After dehydration, the moisture content of the Sichuan pepper raw material is reduced to 10%, which is the first threshold.

[0041] In step S2, the dehydrated Sichuan pepper raw material enters the high-voltage pulsed electric field treatment chamber. The pulse intensity is set to 45 kV / cm, the pulse width to 20 μs, the frequency to 300 Hz, and the waveform to be a square wave. The material flows through for 6 seconds, causing electroporation of the microbial cell membranes attached to the surface of the Sichuan pepper. The material then enters the ultrasonic resonant cavity within 8 seconds. The ultrasonic frequency is set to 40 kHz, and the sound intensity is 90 W / cm. 2 The processing time is 60 seconds. The ultrasonic waves propagate longitudinally along the material flow direction. The high-voltage pulse electric field first creates electroporation, and then the ultrasonic cavitation effect generates asymmetric cavitation at the electroporation location, which completely tears and disintegrates the microbial cell membrane and any possible spore structures. A cell debris filter with a mesh diameter of 1.0 μm is set at the outlet of the ultrasonic resonant cavity to trap the disintegrated microbial debris.

[0042] Step S3: Place the inactivated Sichuan pepper material into a supercritical carbon dioxide treatment container. First, evacuate the container to an absolute pressure of 0.8 kPa, then inject supercritical carbon dioxide. The carbon dioxide flow rate to material mass ratio is set to 1.2 L / min to 1 kg. The supercritical carbon dioxide enters as microbubbles through a microporous distribution plate with a bottom pore size of 30 μm. The stirring paddle rotates the material at 15 rpm. The treatment time is 35 minutes. During this process, the supercritical carbon dioxide reacts with copper and iron ions at the active centers of polyphenol oxidase and peroxidase that may be present in the Sichuan pepper. Complexation irreversibly inactivates two oxidases, preventing browning and flavor deterioration of Sichuan pepper during subsequent storage. Simultaneously, supercritical carbon dioxide dissolves and replaces the free oxygen adsorbed between Sichuan pepper particles and within cell debris, reducing the free oxygen concentration in the treated Sichuan pepper material to below 30 ppm. The supercritical carbon dioxide carrying free oxygen and some low-boiling-point odor aldehydes and ketones is extracted and depressurized to 6 MPa and 28°C to separate odor substances. The carbon dioxide is then compressed and recycled. The Sichuan pepper material in the extraction container is maintained at a negative pressure of 0.09 MPa for 45 seconds to remove residual trace amounts of carbon dioxide.

[0043] Step S4: The stabilized Sichuan pepper material processed in step S3 is backfilled and mixed with the high-boiling-point flavor components captured and stored in the first storage tank and the low-boiling-point flavor components in the second storage tank in step S1. According to the ratio of 120mL of high-boiling-point component and 50mL of low-boiling-point component for every 100kg of dried Sichuan pepper raw material, the high-boiling-point component is first mixed with the material in a closed mixer, and then the low-boiling-point component is added for a second mixing to reproduce the original aroma profile of fresh Sichuan pepper to the greatest extent, thus obtaining the primary Sichuan pepper seasoning.

[0044] Step S5: The primary Sichuan pepper seasoning is conveyed to the dielectric resistance spectrum processing area. The operating frequency sweep range of the processing area is 1MHz-80MHz, the field strength is 50V / cm, and the parallel electrode plate spacing is set to 12mm. The material passes through in a laminar flow state. The high-frequency power supply controls the frequency sweep rate to be 0.3MHz / s. One sweep cycle is from 1MHz to 80MHz. The sweep cycle duration is approximately 263 seconds. The sweep cycle is repeated for 5 cycles. When the sweep frequency passes through the 18MHz±3MHz range, this range coincides with the inherent orientation polarization frequency of water molecules. Free water molecules are directionally bound by the alternating electric field. A large amount of free water in the Sichuan pepper seasoning is converted into bound water, and the water activity decreases from 0.82 to 0.62, which is lower than the second water activity threshold of 0.65. The online water activity detection probe monitors in real time. If the outlet water activity exceeds 0.65, the effective passage path of the material between the electrode plates is automatically extended by the electrode plate length adjustment mechanism until the standard is met.

[0045] Step S6: In a Class 100 sterile environment, the qualified Sichuan pepper seasoning is vacuum sealed and packaged to obtain the finished Sichuan pepper seasoning powder.

[0046] The red Sichuan peppercorns produced in Hanyuan, Sichuan Province, were used for processing in Example 3 above. The finished product was tested, and the results are as follows: the total content of numbing substances was 62.3 mg / g, compared to 68.1 mg / g of the raw material, with a retention rate of 91.5%; among the volatile aroma components, the total peak area retention rate of the main terpenes and linalool was 86.7%; the total bacterial count was below 50 CFU / g, and coliform bacteria were not detected; after being stored for 90 days under accelerated aging conditions at 40℃ and 75% relative humidity (equivalent to 24 months at room temperature), the product did not show browning, had no rancid taste, and the water activity remained stable below 0.64. The microbiological indicators still met the national hygiene standards for condiments. The above results indicate that the method and system of the present invention can effectively maintain the numbing taste, aroma, and microbiological stability of Sichuan peppercorn condiments without adding any chemical preservatives, and has extremely high industrial application value.

[0047] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

Claims

1. A method for the steady-state preservation of additive-free food seasonings, characterized in that, Includes the following steps: S1. Perform gradient vacuum low-temperature dehydration on the seasoning raw materials that have been cleaned and crushed until the moisture content of the raw materials is reduced to the first threshold, and collect the volatile flavor components that escape during the dehydration process simultaneously. S2. Place the dehydrated raw material from step S1 in a high-voltage pulsed electric field treatment chamber and apply a high-voltage pulsed electric field to the raw material to cause electroporation of the cell membrane. Then introduce the raw material into an ultrasonic resonant cavity and use the ultrasonic cavitation effect to cause mechanical disintegration of the cell wall and spore structure of the microorganisms after electroporation. S3. Place the material processed in step S2 into a supercritical carbon dioxide treatment container, inject supercritical carbon dioxide fluid into the container, and use supercritical carbon dioxide to irreversibly inactivate the oxidases and proteases in the material at the molecular structure level, while removing the residual free oxygen in the material. S4. The volatile flavor components collected in step S1 are backfilled into the material processed in step S3, and homogenization and fusion are completed in a closed mixer to obtain a primary seasoning. S5. The primary seasoning obtained in step S4 is transported to the dielectric resistance spectrum processing area. An alternating electric field is applied to the primary seasoning to directionally bind the polar water molecules in the primary seasoning, converting free water into bound water and reducing the water activity to the second threshold. S6. Under sterile conditions, the material that has been treated in step S5 and whose water activity has reached the second threshold is vacuum-sealed and packaged to obtain the finished product.

2. The method according to claim 1, characterized in that, The gradient vacuum low-temperature dehydration in step S1 specifically includes: In the initial stage of dehydration, the vacuum level is controlled at -0.02MPa to -0.05MPa and the temperature at 40-50℃, which allows the surface moisture of the raw material to evaporate rapidly and form microporous channels. In the middle stage of dehydration, the vacuum level is controlled at -0.06MPa to -0.08MPa and the temperature at 30-40℃, and the negative pressure gradient forces the deep moisture inside the raw material to migrate to the surface along the microporous channels. In the final stage of dehydration, the vacuum level is controlled below -0.09MPa and the temperature at 20-25℃, and the partial removal of bound water is completed under conditions without thermal damage. The volatile flavor components are collected using a multi-stage gradient condensation trapping method. The first stage condensation temperature is 0°C to -5°C, which is used to retain terpenes and phenols with boiling points above 80°C. The second stage condensation temperature is -10°C to -20°C, which is used to retain low-molecular-weight aldehydes and ketones with boiling points below 80°C and sulfur-containing flavor substances. Step S1 further includes: storing the flavor components in different boiling point ranges separately in separate tanks, and in step S4, backfilling in layers according to the corresponding ratio of the mass of the dehydrated raw material to the original amount of flavor components released, that is, first backfilling the high boiling point flavor components and mixing them, then backfilling the low boiling point flavor components, and simulating the original flavor profile of the raw material.

3. The method according to claim 1, characterized in that, In step S2, the pulse intensity of the high-voltage pulse electric field is 20-50kV / cm, the pulse width is 10-30μs, the pulse frequency is 100-500Hz, and the pulse waveform adopts an exponential decay wave or a square wave to perform multiple membrane-penetrating blows on the microbial cell membrane during the material flow through the processing chamber. After high-voltage pulsed electric field treatment, the material is directly introduced into the ultrasonic resonant cavity within 10 seconds. The ultrasonic resonant cavity operates at a frequency of 20-40 kHz and a sound intensity of 50-100 W / cm². 2 The ultrasonic treatment time is 30-120 seconds, and the ultrasonic waves propagate in the form of longitudinal waves along the material flow direction. The high-voltage pulsed electric field and the ultrasound form a time-series synergy: the high-voltage pulsed electric field first causes electroporation damage to the microbial cell membrane, which instantaneously increases the cell membrane permeability. Subsequently, the ultrasound cavitation effect preferentially causes asymmetric cavitation at the electroporation site, further tearing the cell membrane pores into irreparable ruptures, causing the cell contents to leak out. Step S2 further includes: setting a cell debris filter at the outlet of the ultrasonic resonant cavity, the filter having a mesh diameter of 0.45-1.2 micrometers, for trapping microbial cell wall fragments after disintegration, while allowing seasoning matrix particles to pass through.

4. The method according to claim 1, characterized in that, In step S3, the pressure of the supercritical carbon dioxide treatment container is 25-45 MPa, the temperature is 35-50℃, and the treatment time is 15-60 minutes; the ratio of supercritical carbon dioxide flow rate to material mass is 0.5-2.0:1, with units of L / min and kg, respectively. Before injecting supercritical carbon dioxide, the treatment container is evacuated to an absolute pressure of less than 1 kPa to remove the original air inside the container. Supercritical carbon dioxide enters the container through a microporous distribution plate at the bottom, with micropores ranging from 10 to 50 μm in diameter. The supercritical carbon dioxide, in the form of microbubbles, travels upwards through the filter media, simultaneously performing three functions: First, supercritical carbon dioxide complexes with metal ions at the active sites of enzyme molecules, causing irreversible renaturation of the enzyme conformation; second, supercritical carbon dioxide dissolves and displaces free oxygen molecules adsorbed between material particles and within cell debris; third, supercritical carbon dioxide carries away short-chain fatty acids and aldehyde-like odor intermediates produced by the enzymatic hydrolysis reaction. Step S3 further includes: drawing supercritical carbon dioxide carrying free oxygen and odorous substances out of the container and then performing depressurization and vaporization to release the odorous substances. The carbon dioxide is then compressed and recycled. At the same time, the material drawn out of the container is maintained under negative pressure for 30-60 seconds to remove residual trace amounts of carbon dioxide.

5. The method according to claim 1, characterized in that, The operating frequency of the intermediate resistance isolation spectrum processing region in step S5 is 1-100MHz, and the field strength is 10-100V / cm. The dielectric resistance spectrum processing zone consists of multiple sets of parallel electrode plates arranged in series along the material conveying direction. The spacing between each set of parallel electrode plates is 5-20mm. The material passes through the gap between the parallel electrode plates in a laminar flow state. The alternating electric field is applied in a frequency sweep mode, that is, it continuously changes from a starting frequency to an ending frequency, with a sweep rate of 0.1-1MHz / s and a sweep period of 10-100 seconds, and the sweep is repeated for 3-10 cycles. During the frequency sweep process, the free water molecules in the compound seasoning undergo dielectric relaxation response under the action of alternating electric field. When the electric field frequency coincides with the inherent orientation polarization frequency of water molecules, the dipole moment of water molecules is oriented and bound, the hydrogen bond network formed between adjacent water molecules is destroyed, and free water is transformed into short-range ordered bound water. Step S5 further includes: setting an online water activity detection probe at the outlet of the dielectric resistance spectrum processing region; when the detected water activity is higher than the second threshold, increasing the processing time by extending the effective energizing path length of the parallel electrode plate until the water activity reaches the standard.

6. A zero-additive food seasoning steady-state preservation processing system, characterized in that, For performing the method according to any one of claims 1-5, comprising: The flavor separation module is used to receive the pulverized seasoning raw materials, perform gradient vacuum low-temperature dehydration on the raw materials, and separate and capture the volatile flavor components that escape from the raw materials during the dehydration process, outputting dehydrated material with low moisture content and liquid volatile flavor components. The microbial lysis module has its input end connected to the output end of the flavor separation module. It is used to receive dehydrated materials and apply high-voltage pulse electric field and ultrasonic oscillation to the dehydrated materials in sequence, so that the microbial cells and spores in the dehydrated materials undergo electroporation and mechanical disintegration, and output the inactivated materials after inactivation of microorganisms. The enzyme inactivation and deoxygenation module has its input end connected to the output end of the microbial lysis module. It is used to receive inactivated materials and inject supercritical carbon dioxide fluid into the inactivated materials. The supercritical carbon dioxide fluid irreversibly inactivates the enzyme molecules in the inactivated materials and replaces the free oxygen in the materials, outputting stabilized materials and waste carbon dioxide carrying free oxygen. The flavor backfilling module has a first input end connected to the output end of the enzyme inactivation and deoxygenation module and a second input end connected to the output end of the flavor separation module. It is used to receive the stabilized material and volatile flavor components from the flavor separation module, backfill the volatile flavor components into the stabilized material and complete the homogenization and mixing, and output the compound seasoning. The water activity control module has its input end connected to the output end of the flavor backfilling module. It is used to receive compound seasonings and apply an alternating electric field to the compound seasonings. The alternating electric field directionally binds the polar water molecules in the compound seasonings, thereby reducing the water activity of the compound seasonings and outputting basic seasonings with the required water activity. The aseptic sealing module has its input end connected to the output end of the water activity control module. It is used to receive basic seasonings and perform vacuum sealing packaging on the basic seasonings under aseptic conditions, and output finished seasoning packages.

7. The system according to claim 6, characterized in that, The flavor separation module contains at least two stages of vacuum belt drying units connected in series and a gradient condensation collection unit connected to the exhaust port of the vacuum belt drying unit. The gradient condensation trapping unit includes a first-stage trapping unit and a second-stage trapping unit. The condensation temperature of the first-stage trapping unit is configured to be 0°C to -5°C and is used to trap high-boiling-point flavor components. The condensation temperature of the second-stage trapping unit is configured to be -10°C to -20°C and is used to trap low-boiling-point flavor components. The flavor separation module also includes a first storage tank and a second storage tank that are respectively connected to the drain ports of the first-stage trap and the second-stage trap. The first storage tank is used to store high-boiling-point flavor components separately, and the second storage tank is used to store low-boiling-point flavor components separately. The flavor backfilling module receives and backfills the two flavor components in the order of first connecting to the outlet of the first storage tank and then connecting to the outlet of the second storage tank.

8. The system according to claim 6, characterized in that, The microbial lysis module comprises a high-voltage pulsed electric field treatment chamber and an ultrasonic resonant cavity connected in series. The high-voltage pulse electric field treatment chamber is equipped with parallel plate electrodes, which are used to apply a pulse electric field to the dewatered material flowing through the treatment chamber. The inner wall of the ultrasonic resonant cavity is attached with a piezoelectric ceramic resonator array, which is used to emit ultrasonic waves to the material flowing through the resonant cavity, causing cavitation bubbles to be generated inside the material. The outlet of the ultrasonic resonant cavity is equipped with a cell debris filter screen with a mesh diameter of 0.45-1.2 micrometers, and a material storage tank is connected downstream of the filter screen. The material conveying pipeline between the high-voltage pulse electric field processing chamber and the ultrasonic resonant cavity has a conveying time corresponding to a length that does not exceed 10 seconds.

9. The system according to claim 6, characterized in that, The enzyme inactivation and deoxygenation module includes a high-pressure vessel, a carbon dioxide storage tank connected to the high-pressure vessel, a gas-liquid separator connected to the outlet of the high-pressure vessel, and a compression reuse pipeline connected between the gas-liquid separator and the carbon dioxide storage tank. The carbon dioxide storage tank is used to supply supercritical carbon dioxide fluid into the high-pressure vessel. The high-pressure container is equipped with a stirring blade, which is used to agitate the inactivated material inside the high-pressure container. The bottom of the high-pressure vessel is provided with a microporous distribution plate with a pore size of 10-50μm. Supercritical carbon dioxide from the carbon dioxide storage tank enters the high-pressure vessel in the form of microbubbles through the microporous distribution plate. The gas-liquid separator is used to separate the mixed gas of carbon dioxide, free oxygen and odor substances discharged from the high-pressure container. The separated carbon dioxide is returned to the carbon dioxide storage tank through a compression and reuse pipeline. The top of the high-pressure vessel is also connected to a vacuum pump and a vacuum evacuation pipeline, which is used to evacuate the high-pressure vessel to an absolute pressure of less than 1 kPa before injecting supercritical carbon dioxide.

10. The system according to claim 6, characterized in that, The water activity regulation module includes at least one set of parallel dielectric electrode plates and a high-frequency power supply connected between the dielectric electrode plates. A material flow channel is formed between the dielectric insulating electrode plates, through which the compound seasonings pass; The high-frequency power supply is used to supply power to the dielectric resistance electrode plate, so that an alternating electric field is formed in the material flow channel. The dielectric barrier electrode plates are arranged in multiple sets in series along the material conveying direction, and the spacing between each set of electrode plates is 5-20mm. The high-frequency power supply has a built-in frequency scanning controller, which is used to control the output frequency of the high-frequency power supply to change continuously from the starting frequency to the ending frequency, forming a sweeping alternating electric field. The outlet of the water activity control module is also equipped with an online water activity detection probe and an electrode plate length adjustment mechanism electrically connected to the detection probe. The electrode plate length adjustment mechanism is used to adjust the processing time by changing the effective path length of the material flowing through the electrode plate according to the water activity value fed back by the detection probe.

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