Selenium-rich duck egg thin salt fine processing technology

Abstract

The present application relates to the technical field of poultry egg food processing, and discloses a rich-selenium duck egg thin-salt fine processing technology, which comprises the following steps: placing fresh rich-selenium duck eggs in a pressure-resistant impregnation reaction kettle, pumping a basic composite permeate into the kettle, replacing the air hole gas by vacuumizing and slowly releasing pressure, opening a circulating pipeline to intercept the permeate to enter a flow tank for real-time detection, based on the detection data, synchronously executing reaction kinetics temperature gradient control, dropping a dynamic compensation liquid to perform double locking dynamic compensation of pH and ORP, and implementing a differential conductivity driven stepwise pulse pressurization within a set operation time, cooling and standing after the end, and finally obtaining finished duck eggs through cleaning, air drying, packaging, water bath sterilization and cooling. The present application combines biochemical microenvironment regulation and control with fluid mechanics intervention, breaks the interface mass transfer barrier, can shorten the production and processing cycle, reduce the overall salt content of the finished product, maintain the tender texture of egg white, and improve the oiling and sanding effect of egg yolk.

Description

Technical Field

[0001] This invention relates to the field of poultry and egg food processing technology, specifically a deep processing technology for selenium-enriched duck eggs with low salt content. Background Technology

[0002] As a poultry egg product with high nutritional value, selenium-enriched duck eggs have always attracted attention in the food industry for their deep processing technology. Traditional salted duck egg processing generally uses static soaking in high-concentration brine or mud curing. This method relies on high osmotic pressure to drive mass transfer. Although it can quickly achieve the oil and sandy texture of the yolk, the finished product has an excessively high salt content, which does not conform to the modern trend of low-sodium and healthy consumption.

[0003] In the transition to low-salt processing, traditional static pickling techniques have revealed significant limitations. Due to the reduced salt concentration in the pickling solution, the osmotic pressure driving force for substance migration into the duck egg weakens, leading to the formation of a concentration polarization boundary layer at the solid-liquid interface. This results in extremely slow mass transfer rates and a significantly longer processing and pickling cycle. During this extended period, the low-salt environment increases the pressure on preservatives to inhibit microbial growth, making the duck eggs susceptible to non-enzymatic spoilage and rancidity in the pickling solution.

[0004] Along with preservation issues comes the deterioration of the product's internal physicochemical quality. Prolonged, inefficient soaking makes it difficult for the deep lipoprotein complex structure to disintegrate, directly resulting in a low rate of oil and sandiness in the finished egg yolk and insufficient accumulation of flavor compounds. Simultaneously, the outer egg white undergoes continuous salting out and moisture loss in a prolonged brine environment, causing severe dehydration and irreversible hardening of the protein.

[0005] To overcome the drawbacks of low-salt curing, the industry is currently attempting to introduce auxiliary physical methods such as pressurization, temperature regulation, or ultrasound to accelerate mass transfer. However, such interventions typically involve blindly operating with preset fixed parameters, lacking dynamic monitoring and feedback on the physicochemical properties of the reaction system and the permeation kinetics of the solid-liquid interface. This static mechanical intervention cannot match the actual mass transfer requirements of poultry eggs at different curing stages, easily leading to increased egg membrane damage rates in actual production, and failing to synergistically resolve the engineering contradictions between low-salt preservation, protein water retention, and yolk sandiness. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a deep processing technology for selenium-enriched duck eggs with low salt content. This technology solves the problems of slow solid-liquid mass transfer rate and long processing cycle under low-salt pickling conditions, as well as the lack of dynamic feedback mechanism in existing intervention methods, which leads to low oil and sand content in the finished egg yolks, dehydration and hardening of the egg whites, and easy spoilage during processing.

[0007] To achieve the above objectives, the present invention provides the following technical solution: This invention provides a process for the deep processing of selenium-enriched duck eggs with low salt content, comprising the following steps: Fresh selenium-enriched duck eggs are selected, and after surface cleaning and drying, they are placed in the material basket inside the pressure-resistant impregnation reactor. The basic composite permeate was pumped into a pressure-resistant impregnation reactor to immerse the selenium-enriched duck eggs. After sealing the pressure-resistant impregnation reactor, vacuuming and pressure holding and slow pressure release were performed in sequence to restore the reactor to normal pressure. Turn on the main circulation pump and bypass pipeline of the pressure-resistant impregnation reactor to divert and retain a portion of the liquid in the total circulation volume, and obtain the permeate to enter the sensor flow cell for real-time detection; Within the set total operation time, based on the real-time detection data of the sensor flow cell, the reaction kinetic temperature gradient control, pH and ORP dual-lock dynamic compensation, and differential conductivity driven stepwise pulse pressurization steps are simultaneously executed in the pressure-resistant impregnation reactor. After the total operation time is completed, stop the cycle and pressurization operation, cool down and keep it static under normal pressure conditions; The liquid is drained, the selenium-enriched duck eggs are taken out, rinsed and air-dried, and then sealed with high-barrier packaging materials and subjected to water bath sterilization and cooling to obtain the finished selenium-enriched duck eggs.

[0008] By adopting the above technical solution, this process does not use traditional static immersion, but instead utilizes dynamic intervention of environmental parameters to reconstruct the mass transfer microenvironment. The specific internal reaction mechanism is as follows: In the initial stage of treatment, the system uses the pressure difference of vacuum holding and alternating depressurization to force out the residual gas in the pores on the eggshell surface. As the external pressure slowly returns to normal, the basic composite permeating liquid is passively drawn in and fills the pores and membrane gaps of the eggshell. This displacement reduces the initial mass transfer resistance at the solid-liquid interface, thereby opening up continuous liquid phase mass transfer channels.

[0009] After the mass transfer channels are opened, the system incorporates reaction kinetic temperature gradient control. The constant-rate, slow heating is used to establish a temperature difference for heat conduction between the inside and outside of the duck egg, while preventing gel denaturation of the outer protein due to drastic local temperature changes. This temperature control logic ensures that the internal mass transfer channels are not blocked by the formation of a dense dehydrated layer.

[0010] As the permeation process progresses, to address the disruption of the intracellular biochemical environment, this approach employs online monitoring via circulating and retaining the permeate, while simultaneously implementing dual pH and ORP locking. The system is forcibly anchored in a weakly acidic state. This promotes phase separation and dissociation of the lipoprotein complex within the yolk, releasing free fatty acids. Furthermore, it provides conditions for the esterification reaction of these free fatty acids with alcohols in the permeate, accelerating the formation of flavor esters. Simultaneously, the dissociation of L-ascorbic acid continuously provides electron donors to the system, maintaining a negative redox potential and inhibiting non-enzymatic browning and rancidity caused by excessive oxidation of polyunsaturated fatty acids.

[0011] As the pickling process progresses into its later stages, the concentration polarization at the interface intensifies. The system no longer relies on time prediction but instead uses the absolute value of the derivative of conductivity with respect to time as a monitoring indicator of the mass transfer rate. Once this derivative approaches its minimum, indicating that conventional osmosis is nearing kinetic equilibrium, the system actively introduces nitrogen to apply a positive pulse pressure, using the hydrostatic pressure difference to force the permeate to overcome osmotic resistance and penetrate deep into the yolk. Subsequent depressurization then triggers the reverse permeation of internal free water. This repeated pressure cycle disrupts the concentration balance at the solid-solid interface, achieving forced hydrostatic osmosis.

[0012] By combining the above processes, through the synergistic effects of channel unblocking, gentle heat conduction, weak acidic antioxidant locking, and forced intervention by fluid mechanics, the technical effects of shortening the production and pickling cycle, reducing the overall salt content of the product, maintaining the tender texture of the egg white, and improving the oily and sandy texture of the egg yolk are achieved.

[0013] Preferably, the preparation method of the basic composite permeate is as follows: using deionized water as a solvent, add 4.5%–5.0% sodium chloride, 4.0%–6.0% ethanol, 8.0%–10.0% D-trehalose, and 79.0%–83.5% deionized water in sequence according to mass percentage. After stirring until completely homogeneous dissolution, add 1.0%–2.0% L-lactic acid aqueous solution dropwise to adjust the initial pH value to 5.2–5.4 to obtain the basic composite permeate.

[0014] By employing the above technical solution, in this formulation, sodium chloride provides the basic osmotic pressure and salty base for pickling, while ethanol enhances permeability by reducing interfacial tension and acts as a substrate for esterification. It is worth noting that D-trehalose, due to its unique steric hindrance and hydration properties, can replace bound water on the surface of egg white proteins. This delays the aggregation and contraction of protein polypeptide chains caused by salting-out during actual processing, maintaining the water-holding capacity of egg white. Furthermore, L-lactic acid regulates the initial pH value, synergistically inhibiting the proliferation of environmental microorganisms under hyperosmotic conditions.

[0015] Preferably, the dynamic compensation solution is prepared by adding 0.5% to 1.0% sodium L-ascorbate and 1.0% to 2.0% L-lactic acid by mass percentage to 97.0% to 98.5% deionized water, and stirring evenly at room temperature to obtain the dynamic compensation solution.

[0016] By adopting the above technical solution, since the alkaline components metabolized inside the poultry eggs will continue to seep out during the pickling process, L-lactic acid, as an exogenous hydrogen ion supplement, can neutralize them, while sodium L-ascorbate, as an electron donor, regulates the redox potential of the system. The combination of the two maintains the dynamic stability of the physicochemical indicators during the processing.

[0017] Preferably, the basic composite permeate solution is pumped into a pressure-resistant impregnation reactor to immerse the selenium-enriched duck eggs. After sealing the pressure-resistant impregnation reactor, vacuuming and pressure holding and slow pressure release operations are performed sequentially to restore the reactor to normal pressure. Specifically, the basic composite permeate solution is pumped into the pressure-resistant impregnation reactor, and the liquid level is controlled to be 5-10 cm above the top material basket. The reactor is sealed, and the vacuum pump is started to reduce the absolute pressure inside the reactor to 0.01-0.03 MPa. The pressure is held for 15-30 minutes, and then the pressure relief valve is opened to slowly restore the absolute pressure to normal pressure of 0.1 MPa.

[0018] By adopting the above technical solution, the set negative pressure range is sufficient to allow the gas trapped in the pores of the eggshell to expand and be emptied. The limitation to slow pressure release is to control the fluid filling rate and prevent instantaneous pressure difference impact from causing the egg to break, thereby reliably achieving the replacement of the mass transfer medium in the pores.

[0019] Preferably, a portion of the liquid in the total circulating liquid volume is diverted and retained, and the permeate is entered into the sensor flow cell for real-time detection. Specifically, 3.0 vol% to 5.0 vol% of the liquid in the total circulating liquid volume is diverted into the inorganic tubular ceramic membrane module for cross-flow filtration, the concentrated liquid is retained and returned to the pressure-resistant impregnation reactor, and the permeate is entered into the sensor flow cell for real-time detection.

[0020] By adopting the above technical solution, considering that there will inevitably be large molecular suspended matter detached in the fermentation and pickling liquid, the inorganic tubular ceramic membrane can separate it in the cross-flow state, so that the permeate entering the flow cell remains clear. This operation avoids protein adsorption passivation on the electrode surface in the flow cell, ensuring the accuracy of online detection data and the stability of continuous operation.

[0021] Preferably, the specific operation of reaction kinetic temperature gradient control is as follows: the temperature inside the vessel is slowly increased from room temperature to 36-38℃ at a constant rate of 0.4-0.6℃ / h through the jacket heating system and maintained at a constant temperature throughout the process.

[0022] By adopting the above technical solution, the extremely slow constant heating rate is essentially to match the radial diffusion rate of inorganic salt ions in the egg white colloidal system, while the set target isothermal range provides the activation energy for lipoprotein dissociation and fatty acid esterification reactions.

[0023] Preferably, the dynamic compensation with dual locking of pH and ORP uses dynamic compensation solution for drip control. Specifically, the PID controller reads the sensor values ​​of the flow cell in real time and automatically controls the dosing pump to drip the dynamic compensation solution, forcibly anchoring the pH value of the continuous phase at 5.35 to 5.45, while maintaining the ORP value at -150 to -200 mV.

[0024] By adopting the above technical solution, within the predetermined weakly acidic and negative redox potential range, not only can the catalytic activity of endogenous lipase be maximized, but also the rancidity caused by non-enzymatic biochemical reactions can be inhibited simultaneously, thereby controlling the synthesis pathway of flavor substances in a targeted manner.

[0025] Preferably, the specific operation of differential conductivity-driven stepped pulse pressurization is as follows: the control system records the absolute value of the derivative of conductivity with respect to time of the continuous phase in the sensor flow cell in real time. When the absolute value of the derivative of conductivity with respect to time is ≤0.01-0.05 mS / (cm·h) for 20-40 minutes, nitrogen is introduced into the reactor until the absolute pressure inside the reactor rises to 0.12-0.15 MPa and is maintained at constant pressure for 45-75 minutes. After the constant pressure is completed, the PID controller controls the exhaust to depressurize at a rate of 0.008-0.012 MPa / min to an absolute pressure of 0.1 MPa, and this monitoring and pressurization / depressurization cycle is automatically repeated during the program depressurization process.

[0026] By adopting the above technical solution, using the absolute value of the conductivity derivative as a feedforward intervention signal to characterize the end point of permeation kinetics, it is possible to trigger inert nitrogen pulse pressurization at the critical point of solid-liquid mass transfer stagnation, and coordinate with programmed pressure relief control to smoothly transition the pressure, thereby intervening in the deep mass transfer efficiency through fluid mechanics.

[0027] Preferably, the total operation time is set to 48–168 hours.

[0028] By adopting the above technical solution and setting reasonable upper and lower limits for the processing cycle, the aim is to provide the time parameters required for the reaction, ensure that the mass exchange process reaches its endpoint, and complete the conversion of the substrate into the target flavor product.

[0029] Preferably, the cooling process involves lowering the temperature inside the reactor to 8–12°C using a refrigerant system and maintaining it at atmospheric pressure for 192–360 hours. The high-barrier packaging uses polyvinylidene chloride (PVDC) high-barrier packaging material for vacuum sealing or nitrogen filling, followed by sterilization in an 85–90°C water bath for 20–30 minutes, and then cooling before being removed from storage.

[0030] By adopting the above technical solution, when the process is nearing its end, the low-temperature static environment causes the dissociated free lipids to aggregate into macroscopic oil droplets, completing the redistribution of internal free water; subsequently, in conjunction with high-barrier packaging materials and water bath sterilization, residual enzymes and microbial communities are inactivated, the biochemical reaction is terminated, and the quality stability of the finished product during its shelf life is ensured.

[0031] This invention provides a refined processing technology for selenium-enriched duck eggs with low salt content. It has the following beneficial effects: 1. This invention breaks through the solid-liquid mass transfer barrier in traditional static pickling, shortens the processing cycle and improves deep penetration efficiency. In the early stage of the process, a continuous liquid phase mass transfer channel is established by vacuuming and slowly depressurizing to remove gas from the eggshell pores. In the middle and late stages of pickling, differential conductivity monitoring is introduced. When the system determines that the mass transfer rate tends to stagnate, nitrogen stepwise pulse pressurization and programmed depressurization are triggered to overcome the concentration polarization phenomenon at conventional interfaces. The reciprocating static pressure difference of the fluid forces the salt and flavor medium to overcome osmotic pressure resistance and migrate to the yolk region.

[0032] 2. This invention improves the oil extraction and sandy texture of egg yolks under low-salt curing conditions and promotes the synthesis of ester flavor compounds. The process uses constant slow heating to provide suitable activation energy for the dissociation of internal lipoproteins. At the same time, by detecting and adding a dynamic compensation solution composed of L-lactic acid and L-ascorbic acid sodium through cross-flow filtration, the reaction vessel is locked in a specific weakly acidic and negative redox potential range. This not only promotes the phase separation and dissociation of free fatty acids from the lipoprotein complex structure, but also triggers the esterification reaction of fatty acids with ethanol in the permeate. Furthermore, the stable electron donor inhibits the non-enzymatic browning and oxidative rancidity of free fatty acids.

[0033] 3. This invention alleviates the problem of severe protein dehydration during the osmosis process, maintaining the water-holding capacity and tender texture of the finished egg white. By introducing D-trehalose into the basic composite osmosis solution, its hydration effect replaces the bound water on the surface of the egg white proteins, delaying the protein polypeptide chain aggregation and salting-out effect induced by hypertonic sodium chloride. Furthermore, the extremely slow temperature gradient control in the early stages prevents the outer layer of duck egg protein from undergoing localized gel denaturation due to thermal shock, thus preventing the formation of a dense water- and salt-barrier barrier. This ensures unimpeded exchange of substances between the inside and outside of the egg white while avoiding irreversible hardening of the egg white texture. Attached Figure Description

[0034] Figure 1 This is a bar chart showing the results of the salt content determination of the finished egg yolks according to the present invention; Figure 2 This is a bar chart showing the results of the determination of the free fat precipitation rate of the finished egg yolk in this invention; Figure 3The figures show the results of the determination of total selenium retention rate and organic selenium content in the present invention. Figure a shows the results of the determination of total selenium retention rate before and after processing, and Figure b shows the results of the determination of organic selenium content percentage in the finished product. Figure 4 The following is a statistical chart showing the pulse pressurization interval and finished product breakage rate of the present invention. In the chart, Figure a is a statistical histogram of the average pulse occurrence interval time of each batch, and Figure b is a statistical histogram of the final finished product breakage rate. Figure 5 The diagram shows the overall quality and technical performance evaluation results of this invention. Figure a is a structural distribution diagram of the overall quality sub-items of each group, and Figure b is a characteristic diagram of the total impact of missing technical features on the final system performance. Detailed Implementation

[0035] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the preparation examples, examples, comparative examples, and test examples. 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.

[0036] Preparation Examples 1-3: Preparation Example 1: This preparation example provides a method for preparing a basic composite permeate and a dynamic compensation fluid, including the following steps: The basic composite osmotic solution was prepared by using deionized water as a solvent and adding 4.8% sodium chloride, 5.0% ethanol, 9.0% D-trehalose, and 81.2% deionized water sequentially by mass percentage under stirring at room temperature. The mixture was stirred until completely homogeneous and dissolved. Then, a 1.5% L-lactic acid aqueous solution was added dropwise to adjust the initial pH to 5.3, yielding the basic composite osmotic solution for later use. The dynamic compensation solution was prepared by adding 0.8% L-ascorbic acid sodium and 1.5% L-lactic acid to 97.7% deionized water by mass percentage and stirring thoroughly at room temperature, yielding the dynamic compensation solution for later use.

[0037] Preparation Example 2: This preparation example provides a method for preparing a basic composite permeate and a dynamic compensation fluid, including the following steps: The basic composite osmotic solution was prepared by using deionized water as a solvent and adding 4.5% sodium chloride, 4.0% ethanol, 8.0% D-trehalose, and 83.5% deionized water sequentially by mass percentage under stirring at room temperature. The mixture was stirred until completely homogeneous and dissolved. Then, a 1.0% L-lactic acid aqueous solution was added dropwise to adjust the initial pH to 5.2, yielding the basic composite osmotic solution for later use. The dynamic compensation solution was prepared by adding 0.5% L-ascorbic acid sodium and 1.0% L-lactic acid to 98.5% deionized water by mass percentage and stirring thoroughly at room temperature, yielding the dynamic compensation solution for later use.

[0038] Preparation Example 3: This preparation example provides a method for preparing a basic composite permeate and a dynamic compensation fluid, including the following steps: The basic composite osmotic solution was prepared by using deionized water as a solvent and adding 5.0% sodium chloride, 6.0% ethanol, 10.0% D-trehalose, and 79.0% deionized water sequentially by mass percentage under stirring at room temperature. The mixture was stirred until completely homogeneous and dissolved. Then, a 2.0% L-lactic acid aqueous solution was added dropwise to adjust the initial pH to 5.4, yielding the basic composite osmotic solution for later use. The dynamic compensation solution was prepared by adding 1.0% L-ascorbic acid sodium and 2.0% L-lactic acid to 97.0% deionized water by mass percentage and stirring thoroughly at room temperature, yielding the dynamic compensation solution for later use.

[0039] Examples 1-4: Example 1

[0040] This embodiment provides a process for the refined processing of selenium-enriched duck eggs with low salt content, including the following steps: Fresh selenium-enriched duck eggs are selected, and damaged and cracked eggs are removed. The surface is mechanically cleaned with room temperature water and dried with a high-pressure air knife. The eggs are then placed in a material basket inside a pressure-resistant impregnation reactor. The basic composite permeate prepared in Example 1 was pumped into the pressure-resistant impregnation reactor, and the liquid level was controlled to be 8 cm above the top material basket. The reactor was sealed, and the vacuum pump was started to reduce the absolute pressure inside the reactor to 0.02 MPa. The pressure was maintained for 20 minutes, and then the pressure relief valve was opened to slowly restore the pressure to the normal pressure state of 0.1 MPa. Turn on the main circulation pump and bypass line of the reactor, so that 4.0 vol% of the total circulating liquid is diverted into the inorganic tubular ceramic membrane module for cross-flow filtration, the concentrate is returned to the main reactor, and the permeate enters the sensor flow cell for real-time detection. The total operation time for this stage is set to 108 hours, during which reaction kinetic temperature gradient control, pH / ORP dual-lock dynamic compensation and differential conductivity driven stepwise pulse pressurization are executed simultaneously. The reaction kinetic temperature gradient control involves slowly raising the temperature inside the reactor from room temperature to 37℃ at a constant rate of 0.5℃ / h using a jacketed heating system and maintaining the temperature constant throughout the process. The pH / ORP dual-locking dynamic compensation uses a PID controller to read the sensor values ​​in the flow cell in real time and automatically control the dosing pump to add the dynamic compensation solution of Preparation Example 1 to counteract the pH increase trend of the continuous phase caused by the leakage of alkaline substances from the poultry egg. Based on previous kinetic calculations, the component ratio of the dynamic compensation solution in Preparation Example 1 has been highly matched with the stoichiometric ratio of the alkaline substance leakage rate and substrate oxidation rate of the target poultry egg at the set temperature. Thus, the pH value of the continuous phase is anchored at 5.40 by the dropwise control of a single solution, while the ORP value is maintained at -175mV. The differential conductivity-driven stepped pulse pressurization system records the absolute value of the derivative of the conductivity of the continuous phase in the flow cell with respect to time, |dκ / dt|, in real time for the control system. When |dκ / dt| ≤ 0.03 mS / (cm·h) is continuously monitored for 30 min, nitrogen is introduced into the reactor until the absolute pressure inside the reactor rises to 0.135 MPa and is maintained at constant pressure for 60 min. After the constant pressure is completed, the PID controller controls the electromagnetic proportional regulating valve to exhaust gas and depressurize at a rate of 0.010 MPa / min to the absolute pressure of 0.1 MPa. During this stage, this monitoring and pressurization / depressurization cycle is automatically repeated. After the set total time is completed, stop the circulation and pressurization operation, and use the jacketed refrigerant system to lower the temperature inside the vessel to 10°C. Then, let it stand under normal pressure for 264 hours. Finally, drain the permeate, remove the duck eggs, rinse them with clean water and air dry them, vacuum seal them with polyvinylidene chloride high-barrier packaging material, sterilize them in an 88℃ water bath for 25 minutes, and then cool them before taking them out of the warehouse. Example 2

[0041] This embodiment provides a process for the refined processing of selenium-enriched duck eggs with low salt content, including the following steps: Fresh selenium-enriched duck eggs are selected, and damaged and cracked eggs are removed. The surface is mechanically cleaned with room temperature water and dried with a high-pressure air knife. The eggs are then placed in a material basket inside a pressure-resistant impregnation reactor. The basic composite permeate solution prepared in Example 2 was pumped into the pressure-resistant impregnation reactor, and the liquid level was controlled to be 5 cm above the top material basket. The reactor is sealed, and the vacuum pump is started to reduce the absolute pressure inside the reactor to 0.03 MPa. The pressure is maintained for 15 minutes, and then the pressure relief valve is opened to slowly restore the pressure to the normal pressure state of 0.1 MPa. Turn on the main circulation pump and bypass pipeline of the reactor, so that 3.0 vol% of the total circulating liquid is diverted into the inorganic tubular ceramic membrane module for cross-flow filtration, the concentrate is returned to the main reactor, and the permeate enters the sensor flow cell for real-time detection. The total operation time for this stage is set to 168 hours, during which reaction kinetic temperature gradient control, pH / ORP dual-lock dynamic compensation, and differential conductivity driven stepwise pulse pressurization are executed simultaneously. The reaction kinetic temperature gradient control involves slowly raising the temperature inside the reactor from room temperature to 36℃ at a constant rate of 0.4℃ / h using a jacketed heating system and maintaining the temperature constant throughout the process. The pH / ORP dual-lock dynamic compensation is a PID controller that reads the values ​​of the flow cell sensor in real time and automatically controls the dosing pump to add the dynamic compensation solution of Preparation Example 2. Based on the previous kinetic calculation, the component ratio of the dynamic compensation solution in Preparation Example 2 has been highly matched with the stoichiometric ratio of the alkaline substance leaching rate and substrate oxidation rate of the target poultry egg at the set temperature. Thus, the pH value of the continuous phase is anchored at 5.35 by the drop strengthening of a single solution, while the ORP value is maintained at -150mV. The differential conductivity-driven stepped pulse pressurization system records the absolute value of the derivative of the conductivity of the continuous phase in the flow cell with respect to time, |dκ / dt|, in real time for the control system. When |dκ / dt| ≤ 0.05 mS / (cm·h) is continuously monitored for 20 min, nitrogen is introduced into the reactor until the absolute pressure inside the reactor rises to 0.12 MPa and is maintained at constant pressure for 45 min. After the constant pressure is completed, the PID controller controls the electromagnetic proportional regulating valve to exhaust gas and depressurize at a rate of 0.008 MPa / min to the absolute pressure of 0.1 MPa. During this stage, this monitoring and pressurization / depressurization cycle is automatically repeated. After the set total time is completed, stop the circulation and pressurization operation, and use the jacketed refrigerant system to lower the temperature inside the vessel to 8°C. Then, let it stand under normal pressure for 360 hours. Finally, drain the permeate, remove the duck eggs, rinse them with clean water and air dry them, then use polyvinylidene chloride high-barrier packaging material for nitrogen-filled and sealed packaging, place them in an 85℃ water bath for sterilization for 30 minutes, and cool them before removing them from the warehouse. Example 3

[0042] This embodiment provides a process for the refined processing of selenium-enriched duck eggs with low salt content, including the following steps: Fresh selenium-enriched duck eggs are selected, and damaged and cracked eggs are removed. The surface is mechanically cleaned with room temperature water and dried with a high-pressure air knife. The eggs are then placed in a material basket inside a pressure-resistant impregnation reactor. The basic composite permeate solution prepared in Example 3 was pumped into the pressure-resistant impregnation reactor, and the liquid level was controlled to be 10 cm above the top material basket. The reactor is sealed, and the vacuum pump is started to reduce the absolute pressure inside the reactor to 0.01 MPa. The pressure is maintained for 30 minutes, and then the pressure relief valve is opened to slowly restore the pressure to the normal pressure state of 0.1 MPa. Turn on the main circulation pump and bypass line of the reactor, so that 5.0 vol% of the total circulating liquid is diverted into the inorganic tubular ceramic membrane module for cross-flow filtration, the concentrate is returned to the main reactor, and the permeate enters the sensor flow cell for real-time detection. The total operation time for this stage is set to 48 hours, during which reaction kinetic temperature gradient control, pH / ORP dual-lock dynamic compensation, and differential conductivity driven stepwise pulse pressurization are executed simultaneously. The reaction kinetic temperature gradient control involves slowly raising the temperature inside the reactor from room temperature to 38℃ at a constant rate of 0.6℃ / h using a jacketed heating system and maintaining the temperature constant throughout the process. The pH / ORP dual-lock dynamic compensation is a PID controller that reads the values ​​of the flow cell sensor in real time and automatically controls the dosing pump to add the dynamic compensation solution of Preparation Example 3. Based on the previous kinetic calculation, the component ratio of the dynamic compensation solution in Preparation Example 3 has been highly matched with the stoichiometric ratio of the alkaline substance leaching rate and substrate oxidation rate of the target poultry egg at the set temperature. Thus, the pH value of the continuous phase is anchored at 5.45 by the drop strengthening of a single solution, while the ORP value is maintained at -200mV. The differential conductivity-driven stepped pulse pressurization system records the absolute value of the derivative of the conductivity of the continuous phase in the flow cell with respect to time, |dκ / dt|, in real time for the control system. When |dκ / dt| ≤ 0.01 mS / (cm·h) is continuously monitored for 40 min, nitrogen is introduced into the reactor until the absolute pressure inside the reactor rises to 0.15 MPa and is maintained at constant pressure for 75 min. After the constant pressure is completed, the PID controller controls the electromagnetic proportional regulating valve to exhaust gas and depressurize at a rate of 0.012 MPa / min to the absolute pressure of 0.1 MPa. During this stage, this monitoring and pressurization / depressurization cycle is automatically repeated. After the set total time is completed, stop the circulation and pressurization operation, and use the jacketed refrigerant system to lower the temperature inside the vessel to 12°C. Then, let it stand under normal pressure for 192 hours. Finally, drain the permeate, remove the duck eggs, rinse them with clean water and air dry them, vacuum seal them with polyvinylidene chloride high-barrier packaging material, sterilize them in a 90℃ water bath for 20 minutes, and then cool them before taking them out of the warehouse. Example 4

[0043] This embodiment provides a process for the refined processing of selenium-enriched duck eggs with low salt content, including the following steps: Fresh selenium-enriched duck eggs are selected, and damaged and cracked eggs are removed. The surface is mechanically cleaned with room temperature water and dried with a high-pressure air knife. The eggs are then placed in a material basket inside a pressure-resistant impregnation reactor. The basic composite permeate prepared in Example 1 was pumped into the pressure-resistant impregnation reactor, and the liquid level was controlled to be 8 cm above the top material basket. The reactor was sealed, and the vacuum pump was started to reduce the absolute pressure inside the reactor to 0.02 MPa. The pressure was maintained for 20 minutes, and then the pressure relief valve was opened to slowly restore the pressure to the normal pressure state of 0.1 MPa. Turn on the main circulation pump and bypass line of the reactor, so that 4.0 vol% of the total circulating liquid is diverted into the inorganic tubular ceramic membrane module for cross-flow filtration, the concentrate is returned to the main reactor, and the permeate enters the sensor flow cell for real-time detection. The total operation time for this stage is set to 48 hours, during which reaction kinetic temperature gradient control, pH / ORP dual-lock dynamic compensation, and differential conductivity driven stepwise pulse pressurization are executed simultaneously. The reaction kinetic temperature gradient control involves slowly raising the temperature inside the reactor from room temperature to 38℃ at a constant rate of 0.6℃ / h using a jacketed heating system and maintaining the temperature constant throughout the process. The pH / ORP dual-locking dynamic compensation uses a PID controller to read the sensor values ​​in the flow cell in real time and automatically control the dosing pump to add the dynamic compensation solution of Preparation Example 1 to counteract the pH increase trend of the continuous phase caused by the leakage of alkaline substances from the poultry egg. Based on previous kinetic calculations, the component ratio of the dynamic compensation solution in Preparation Example 1 has been highly matched with the stoichiometric ratio of the alkaline substance leakage rate and substrate oxidation rate of the target poultry egg at the set temperature. Thus, the pH value of the continuous phase is anchored at 5.40 by the dropwise control of a single solution, while the ORP value is maintained at -175mV. The differential conductivity-driven stepped pulse pressurization system records the absolute value of the derivative of the conductivity of the continuous phase in the flow cell with respect to time, |dκ / dt|, in real time for the control system. When |dκ / dt| ≤ 0.05 mS / (cm·h) is continuously monitored for 20 min, nitrogen is introduced into the reactor until the absolute pressure inside the reactor rises to 0.15 MPa and is maintained at constant pressure for 45 min. After the constant pressure is completed, the PID controller controls the electromagnetic proportional regulating valve to exhaust gas and depressurize at a rate of 0.012 MPa / min to the absolute pressure of 0.1 MPa. During this stage, this monitoring and pressurization / depressurization cycle is automatically repeated. After the set total time is completed, stop the circulation and pressurization operation, and use the jacketed refrigerant system to lower the temperature inside the vessel to 10°C. Then, let it stand under normal pressure for 192 hours. Finally, drain the permeate, remove the duck eggs, rinse them with clean water and air dry them, vacuum seal them with polyvinylidene chloride high-barrier packaging material, sterilize them in an 88℃ water bath for 25 minutes, and then cool them before taking them out of the warehouse.

[0044] Comparative Examples 1-5: Comparative Example 1: Compared with Example 1, the difference is that no ethanol is added to the basic composite permeation solution, and no L-lactic acid aqueous solution is used to adjust the initial pH value. No L-lactic acid is added to the dynamic compensation solution and no pH lock control is performed. The missing mass percentages in the formula are all made up with deionized water. All other aspects are the same.

[0045] Comparative Example 2: Compared with Example 1, the difference is that D-trehalose is not added to the basic composite permeation solution, L-ascorbic acid sodium is not added to the dynamic compensation solution and ORP lock-in control is not performed, and the missing mass percentages in the formula are made up with deionized water, while the rest are the same.

[0046] Comparative Example 3: Compared with Example 1, the difference is that the differential conductivity-driven stepped pulse pressurization step is not performed, and the absolute pressure inside the vessel is maintained at 0.1 MPa throughout the entire operation. All other aspects are the same.

[0047] Comparative Example 4: Compared with Example 1, the difference is that in the differential conductivity driven step-by-step pulse pressurization step, after the constant pressure is maintained, the pressure relief valve is directly opened to quickly release the absolute pressure in the vessel to 0.1 MPa within 1 minute, without performing the 0.010 MPa / min programmed step-by-step pressure relief. All other aspects are the same.

[0048] Comparative Example 5: Compared with Example 1, the difference is that the basic composite permeation solution is only a sodium chloride aqueous solution with a mass fraction of 4.8%, without the addition of ethanol and D-trehalose, and the entire process is only static pickling at room temperature and pressure, without any process control steps such as negative pressure replacement, temperature gradient control, dynamic compensation and pulse pressurization, while the rest are the same.

[0049] Test Examples 1-4: Test Example 1: Verification of the low-salt demulsification and oil extraction mechanism based on the coupling of dielectric constant and isoelectric point phase transition: The specific experimental steps are as follows: Take 15 finished duck eggs from each of the embodiments and comparative examples after solidification and packaging, peel off the eggshell and egg white, separate the complete hard yolk, crush and mix them evenly in an agate mortar, and prepare a homogeneous sample to be tested.

[0050] Weigh 5.00g of the homogenized sample above and place it in an Erlenmeyer flask. Add boiling water to dissolve the sample and bring the volume to 100mL. After filtration, take the filtrate and determine the sodium chloride mass fraction in the sample using the silver nitrate titration method for chloride determination in food according to national standards. Perform three parallel determinations and take the average value to calculate the salt content of the finished egg yolk.

[0051] Weigh 10.00g of homogenized sample and place it in a Soxhlet extractor. Use petroleum ether as solvent and continuously reflux in a water bath for 8 hours. After removing the solvent by rotary evaporation, dry the extract at a constant temperature in an oven until constant weight. The mass of the extract obtained is the mass of the fat that has undergone demulsification and is free in the egg yolk.

[0052] Another 5.00g homogenized sample was placed in a hydrolysis tube, and hydrochloric acid solution was added to hydrolyze it in a boiling water bath to destroy all bound lipoprotein networks. Subsequently, it was extracted with petroleum ether and evaporated to dryness and weighed to determine the total fat mass of the sample, including free and bound fats.

[0053] Divide the mass of free fat measured in step 3 by the mass of total fat measured in step 4 and multiply by 100% to calculate the free fat precipitation rate of each sample.

[0054] Table 1. Test results of salt content and free fat precipitation rate of finished egg yolks in each example and comparative example.

[0055] Conclusion Analysis Combining Table 1 and Figure 1 It is evident that traditional low-salt static curing methods cannot achieve the demulsification and separation of egg yolk lipoproteins without environmental intervention. Observation Figure 1 Bar chart of the results of salt content determination of finished egg yolks and Figure 2 The distribution characteristics of the bar chart showing the free fat precipitation rate of the finished egg yolks are readily apparent. Comparative Example 5 has an extremely low bar height, with a finished egg yolk salt content of only 1.43% and a corresponding free fat precipitation rate as low as 14.56%. This phenomenon aligns with the common knowledge in the field that low ionic strength cannot compress the electric double layer and produce a salting-out effect. However... Figure 1 In the overall trend, the test results of Examples 1 to 4 constitute an extremely strong contrast. Figure 1 The bar chart of the finished egg yolk salt content determination results shows that the sodium chloride mass fraction in the system is limited to an extremely low range of 1.71% to 2.14%, but... Figure 2 The height of the corresponding bars in the bar chart of the determination of the free fat precipitation rate of the finished egg yolk all jumped to the high position, all distributed between 82.15% and 87.32%, proving that the phase structure still completed the reorganization and lipid precipitation under extremely low salt concentration.

[0056] The underlying causes of this unconventional macroscopic phenomenon can be definitively confirmed by the data decline in the chart of Comparative Example 1. Even after removing the ethanol and lactic acid adjustments from the basic composite permeate solution, even... Figure 1 The bar chart of the finished egg yolk salt content determination results shows that Comparative Example 1 maintained the same low-salt environment of 1.68%. Figure 2The bar chart showing the free fat extraction rate of the finished egg yolk plummeted to 21.47%. This significant drop directly confirms that the infiltration of low-molecular-weight alcohols into the egg yolk microenvironment resulted in a reduction effect on the macroscopic dielectric constant of the continuous phase, leading to a sudden amplification of electrostatic attraction under Coulomb's law. Simultaneously, the buffer system provided by lactic acid anchored the system's pH value to near the isoelectric point of vitellin, forcibly reducing the net charge of the protein side chains to zero. The disappearance of microscopic electrostatic repulsion and the collapse of the hydration layer overlapped at this moment, allowing the system to instantly overcome the free energy barrier of the ruptured emulsion network, ultimately manifesting as a high oil extraction characteristic on the macroscopic chart, independent of inorganic salt concentration.

[0057] The disruptive effects of mass transfer kinetics during the experiment are clearly evident in the data distribution of Comparative Example 3. When the process route eliminates the pulsed pressurization logic driven by conductivity derivatives... Figure 1 The salt content of the finished egg yolks, as shown in the bar chart, dropped to a low of 0.84% ​​in Comparative Example 3. Figure 2 The free fat precipitation rate of the finished egg yolk also bottomed out at 18.22% in the bar chart. This interruption of mass exchange verifies that trehalose does indeed form a very strong steric hindrance effect when constructing the interfacial protective network. This indicates that without intermittent positive mechanical pressure to overcome mass transfer stagnation, the aforementioned chemical thermodynamic intervention substances simply cannot penetrate the dense barrier to reach the target site inside the egg yolk. The control conditions in each dimension do not exist in isolation in the system, but rather rely on a deep interlocking of fluid dynamic pulse delivery and thermodynamic microenvironment reconstruction, synergistically completing the phase change solidification of the internal colloidal structure under strict low-salt constraints.

[0058] Test Example 2: Verification of the Selenium Retention and Antioxidant Mechanism Based on Spatial Hindrance Network and Thermodynamic Locking The specific experimental steps are as follows: Fresh selenium-enriched duck eggs before processing and finished selenium-enriched duck eggs after solidification were selected from the corresponding batches of Examples 1 to 4 and Comparative Examples 1 to 5 as experimental subjects. The edible parts of each egg, including the egg white and yolk, were peeled off and homogenized using a high-speed tissue homogenizer to prepare homogenous test samples.

[0059] Accurately weigh 1.00 g of each sample and place it in a polytetrafluoroethylene microwave digestion vessel. Add a mixed acid solution of nitric acid and hydrogen peroxide, and perform a gradient temperature-controlled digestion program in a microwave digester. After acid removal, use hydrochloric acid solution to completely reduce the hexavalent selenium to tetravalent selenium. After adjusting the volume, determine the total selenium mass fraction of the sample using hydride generation-atomic fluorescence spectrometry. Compare the values ​​before and after processing to calculate the total selenium retention rate.

[0060] Take another 2.00g of homogenized sample of each component and place it in a centrifuge tube. Add Tris-HCl buffer solution containing streptomycin and papain, and place it in a constant temperature shaker in the dark for 16 hours to perform an enzymatic extraction program. After high-speed centrifugation, filter the supernatant using a microporous membrane.

[0061] The various forms of selenium in the supernatant were separated and determined using a liquid chromatography-inductively coupled plasma mass spectrometry system. Selenomethionine and selenocysteine ​​were qualitatively identified based on chromatographic retention time, and the percentage of the sum of the masses of these two organic selenium forms in the total mass of the finished product was quantitatively calculated using the external standard method to obtain data on the proportion of organic selenium content.

[0062] Table 2. Test results of total selenium retention rate and organic selenium content for each example and comparative example.

[0063] Conclusion Analysis Combine Table 2 and Figure 3 It is evident that prolonged immersion in a liquid environment exposes the fragile, water-soluble macromolecules within poultry eggs to an extremely high risk of leakage. (Observation) Figure 3 (a) The results of the total selenium retention rate measurement before and after system processing show that the total selenium retention rate of Comparative Example 5, which is based on traditional low-salt static processing, is only 67.34%. This low data trend directly confirms the spontaneous mass transfer process that occurs under the drive of concentration gradient, indicating that the conventional static pickling system is simply unable to prevent the internal selenoamino acids from being lost in large quantities across the eggshell micropores to the external aqueous phase.

[0064] In stark contrast, when D-trehalose was introduced to construct a spatial network in Examples 1 to 4, Figure 3 (a) The data points in the total selenium retention rate determination results before and after system processing show an extremely stable high-level convergence trend, all firmly locked within a narrow range of 91.50% to 94.08%. This hydrogen bond network formed by the tight binding of polyhydroxy molecules and polar groups on the protein surface at the microscopic interface has essentially successfully reconstructed a dense barrier.

[0065] The core dominance of this interception mechanism can be fully confirmed by the data anomalies in Comparative Example 2. Once the barrier constructed by trehalose is severed, Figure 3 (a) The results of the total selenium retention rate measurement before and after system processing showed that the data trajectory of Comparative Example 2 dropped, directly hitting the bottom at 54.32%, which confirmed from the reverse perspective that the mass transfer resistance layer plays an irreplaceable role in inhibiting the diffusion path of macromolecules.

[0066] While simple interception mechanisms can limit macroscopic molecular migration, free radical attacks and dissolved oxygen consumption in fluid processing environments still constantly threaten the microscopic molecular structure of organic selenium. Highly bioactive organic selenium is easily degraded after being removed from the antioxidant system of the original living organism in the egg, transforming into a less active inorganic form. [Examine] Figure 3 (b) The results of the determination of the organic selenium content in the finished product showed that the organic selenium content in Examples 1 to 4 was consistently maintained at an excellent level of 85.04% to 88.21%. The reason for this excellent chemical stability lies in the fact that the dynamic compensation system of this process continuously constructs a non-equilibrium reducing thermodynamic field in the flow cell.

[0067] The low redox potential provided by sodium L-ascorbate preferentially consumes various electrophilic oxidizing groups that have infiltrated the microenvironment, thereby locking the side-chain configuration of selenoamino acids extremely stably on the thermodynamic base. The necessity of this reducing protection is also clearly demonstrated in the test results of Comparative Example 2. When this negative potential intervention mechanism is removed, Figure 3 (b) The determination of the proportion of organic selenium in the finished product revealed that the proportion of organic selenium in the sample of Comparative Example 2 rapidly declined to 43.19%. This drastic molecular morphological degradation profoundly reveals the structural fragility of selenium-rich components in a conventional aqueous processing environment. Cross-validation of physical and chemical dimensions confirms that the steric network must be nested and tightly interlocked with the reducing chemical field in order to truly achieve the targeted retention and solidification of key micronutrients in their active form during the long fluid permeation cycle.

[0068] Test Example 3: Verification of Differential Conductivity Mass Transfer Feedback and Extremely Slow Pressure Relief Explosion-Proof Mechanism: The specific experimental steps are as follows: During the execution of each batch of processes, the programmable logic controller backend of the pressure-resistant impregnation reactor is connected to export a complete time series data file of the change in the conductivity of the continuous phase in the sensor flow cell over time.

[0069] The data calculation module extracts all time points when the absolute value of the conductivity derivative |dκ / dt| reaches the system's set threshold and triggers the nitrogen pressurization action into the reactor. The time difference between two adjacent pulse pressurization actions within the entire pickling cycle is statistically analyzed, and the average interval between pulse pressurization events in each process group is calculated. For comparative groups without conductivity monitoring or pulse program activation, the result is recorded as "not triggered."

[0070] After the set total time for each group is completed and the eggs are sterilized and cooled in a high-temperature water bath before being taken out of storage, a dedicated inspection staff will conduct an appearance inspection on 300 randomly selected finished duck eggs from each group under a room-temperature lighting table.

[0071] Manually inspect each egg individually for through cracks, hidden micro-cracks, or large-area shell breakage accompanied by contents overflow, and record the cumulative total number of such defective products in each batch.

[0072] The breakage rate of each batch of finished products is calculated by dividing the total number of non-conforming products screened in a single batch by the total sample size of 300.

[0073] Table 3. Statistics on pulse pressure interval and finished product breakage rate for each embodiment and comparative example.

[0074] Conclusion Analysis Combined with Table 3 and Figure 4 It is known that the eggshell, as a natural microporous ceramic matrix composite material, exhibits extremely strong asymmetry in its mechanical properties. It can withstand a certain intensity of external positive pressure penetration, but is extremely sensitive to tensile stress from the inside out. (Observation) Figure 4 (a) Statistical histogram of average pulse interval time for each batch. The pulse interval times automatically recorded and triggered in Examples 1 to 4 were 11.2h, 9.4h, 14.7h, and 12.1h, respectively. This dynamic feedback cycle reveals that the trehalose hydrogen bond network at the microscopic level, while restricting the outward permeation of internal nutrients, inevitably causes intermittent blockage of active mass transfer from the outside to the inside. The control system accurately applies positive mechanical pressure at the critical point of mass transfer resistance by capturing the microscopic signal of the continuous phase conductivity polarization flattening in real time, forcing the fluid to forcefully squeeze into the microporous structure, thereby breaking the deadlock and reactivating the permeation dynamics of the solution system.

[0075] Once this forced mass transfer, established by external mechanical intervention, is formed, the subsequent release of deep internal pressure becomes the core engineering obstacle that determines whether the process can be successfully implemented. Figure 4 (b) The statistical histogram of the final product breakage rate provides significant feedback from the engineering field regarding the test records of Comparative Example 4. When the pre-programmed slow depressurization mechanism was canceled and the pressure inside the vessel was emptied in a very short time, the huge pressure difference instantly formed inside and outside the eggshell caused the accumulated microbubbles to undergo explosive expansion in the pores. This uncontrollable radial tensile stress directly increased the material breakage rate of Comparative Example 4 to 38.67%, resulting in a decrease in the yield. In stark contrast, after executing the slow depressurization procedure, the breakage rates of Examples 1 to 4 were strongly compressed to within the safe thresholds of 0.67%, 1.33%, 0.33%, and 1.00%, respectively. The weak and uniform depressurization rate provided ample diffusion relaxation time for the compressed nitrogen and endogenous carbon dioxide inside the pores, allowing the gas to slowly seep out of the shell along with the fluid, truly achieving smooth material breathing at the processing scale. Even Figure 4(a) The statistical histogram of the average pulse occurrence interval for each batch shows that Comparative Example 3 was in a non-triggered state because the pulse program was not started, and in Figure 4 (b) The statistical histogram of the final product breakage rate showed an extremely low breakage rate of 0.33%. However, considering the long-term stagnation of material exchange within the product, it can be determined that this apparent static engineering safety comes at the cost of sacrificing core curing quality. Differential conductivity driving breaks the mass transfer deadlock that osmotic pressure cannot overcome, while the extremely stringent boundary conditions of slow-release pressure relief operation fundamentally safeguard the structural integrity during large-scale production. The two complete a logical closed loop of forced osmosis and non-destructive stress release within a complex fluid dynamics framework.

[0076] Test Example 4: Comparative analysis of the overall technical effects and synergistic advantages of this invention: The specific experimental steps are as follows: The finished selenium-enriched duck eggs from the corresponding batches of Examples 1 to 4 and Comparative Examples 1 to 5, as well as the monitoring data files retained from the early processing stage, were selected as the evaluation objects.

[0077] The data on the free fat extraction rate from the previous test were extracted and converted into a demulsification and oil extraction efficiency score of 25 points after linear normalization. At the same time, the data on the proportion of organic selenium content were extracted and converted into a nutrient locking efficiency score of 25 points using the same normalization algorithm.

[0078] Fifteen egg yolks from each batch were extracted, cut open along the equatorial plane, and puncture tests were performed on the outer, middle, and core layers of the yolk using a cylindrical probe of a texture analyzer to obtain hardness values. The relative standard deviation of the hardness values ​​at different depths of a single egg yolk was calculated. By taking the reciprocal of this relative standard deviation and performing data smoothing mapping, a texture homogeneity score of 25 points was obtained, which characterizes the consistency of mass transfer kinetics diffusion within the egg yolk.

[0079] Summarize the finished product damage rate statistics obtained during the batch count stage, calculate the finished product integrity rate for each batch, and map it to the project integrity rate score of 25 points according to the proportional coefficient.

[0080] The scores of the four dimensions of demulsification and oil extraction efficiency, nutrient locking efficiency, texture uniformity, and process integrity rate, which were independently measured above, were directly summed without weights to calculate the overall quality assessment score of each group of processes.

[0081] Table 4. Evaluation data of the overall technical performance of each embodiment and comparative example, including sub-items and total score.

[0082] Conclusion Analysis: Combine Table 4 and Figure 5It is evident that examining the internal logical constraints of a multidimensional evaluation system can directly expose how single-point technological deficiencies lead to the deterioration of overall processing results. Combined with previous routine laboratory tests and observations, relying solely on osmotic pressure difference is no longer sufficient to meet the dual demands of modern deep processing for phase recombination and trace element solidification. This limitation of the mechanism is confirmed in Comparative Example 5. Figure 5 (b) The overall impact of missing technical features on the final system performance is shown to be only 48.1, which proves that the conventional low-salt static environment is in a state of comprehensive low-level failure.

[0083] To investigate the specific causes of process failure, it is necessary to analyze the independent performance of each evaluation dimension. Observation Figure 5 (a) The structural distribution diagram of the comprehensive quality sub-dimensions of each group reveals that in Comparative Example 1, which excludes ethanol and dynamic pH correction, the system achieved a nutrient locking efficiency of 20.8 points due to the steric hindrance of trehalose. However, due to the excessive rigidity of the hydration layer at the microscale, the material lost its free lipid basis, resulting in a decrease in its demulsification and oil extraction efficiency score to 5.3. Without the support of thermodynamic demulsification phase transition, this isolated micronutrient protection process route completely loses its practical significance for engineering implementation. The vacant spatial hydrogen bond network and Comparative Example 2, which compensates for negative potential, exhibit completely opposite defect characteristics. Figure 5 (a) The structural distribution chart of the comprehensive quality sub-dimensions of each group recorded that its demulsification and oil extraction efficiency reached 20.9 points, but its nutrient locking efficiency dropped to 9.8 points. The highly open and oxygen-rich fluid exchange environment led to a large loss and oxidative damage of organic selenium, directly causing the product to lose its functional core competitiveness.

[0084] The resistance in the mass transfer process constitutes a technical bottleneck for engineering implementation, a phenomenon particularly evident in the data distribution of Comparative Example 3 and Comparative Example 4. In Comparative Example 3, due to the lack of conductivity polarization identification and pulsed pressure intervention, the steric hindrance formed by trehalose on the surface blocked the deep mass transfer within the material. Figure 5 (a) The structural distribution chart of the comprehensive quality sub-dimensions of each group clearly shows that its texture homogeneity score has dropped to 6.5. The large-scale half-cooked state inside has rendered the physicochemical indicators established on the outer layer an empty shell with no application value. The operation of Comparative Example 4 was to remove the step-down pressure relief program when the first three functions were running at full capacity. The rapid pressure relief caused a large number of eggshells to break in a short period of time. Figure 5 (a) The project integrity score of only 15.2 points in the overall quality sub-dimension structure distribution chart of each group wipes out all the quality advantages established in the previous thermodynamic and fluid dynamic operations.

[0085] The data from the example set fully demonstrate the necessity of multiple mechanism coupling. Figure 5(a) In the structural distribution chart of the comprehensive quality sub-items of each group, the scores of all four dimensions in Examples 1 to 4 remained highly stable at above 21 points, and in Figure 5 (b) The overall score for the total impact of missing technical features on the final system performance was close to the maximum score. The high balance at the macroscopic data level directly reflects the tight integration of microscopic mechanisms. The reduced dielectric constant and isoelectric point phase transition laid the foundation for the recombination of free lipids, the trehalose steric hindrance and reduction field constructed a defense system against internal nutrient loss, the conductivity difference drove the breaking of the mass transfer deadlock caused by the interface defense, and the extremely slow pressure relief process resolved the expansion stress remaining from the mechanically forced mass transfer. These four process logics formed an inseparable technical closed-loop chain, creating a brand-new path for the structural recombination of selenium-rich eggs through low-temperature deep processing, while completely abandoning the dependence on high salt ion strength.

Claims

1. A deep processing technology for selenium-enriched duck eggs with low salt content, characterized in that, Includes the following steps: Fresh selenium-enriched duck eggs are selected, and after surface cleaning and drying, they are placed in the material basket inside the pressure-resistant impregnation reactor. The basic composite permeation solution is pumped into the pressure-resistant impregnation reactor to immerse the selenium-enriched duck eggs. After sealing the pressure-resistant impregnation reactor, vacuuming and pressure holding and slow pressure release operations are performed in sequence to restore the reactor to normal pressure. Turn on the main circulation pump and bypass pipeline of the pressure-resistant impregnation reactor, divert and retain a portion of the liquid in the total circulation volume, and obtain the permeate to enter the sensor flow cell for real-time detection; Within the set total operation time, based on the real-time detection data of the sensor flow cell, the reaction kinetic temperature gradient control, pH / ORP dual-lock dynamic compensation, and differential conductivity driven stepwise pulse pressurization steps are simultaneously executed in the pressure-resistant impregnation reactor. After the total operation time is completed, stop the cyclic and pressurization operation, cool down and keep it static under normal pressure. The liquid is drained, the selenium-enriched duck eggs are taken out, rinsed and air-dried, and then sealed with high-barrier packaging materials and subjected to water bath sterilization and cooling operations to obtain the finished selenium-enriched duck eggs.

2. The deep processing technology for selenium-enriched duck eggs with light salting according to claim 1, characterized in that, The preparation method of the basic composite permeate is as follows: Using deionized water as a solvent, 4.5%–5.0% sodium chloride, 4.0%–6.0% ethanol, 8.0%–10.0% D-trehalose, and 79.0%–83.5% deionized water were added sequentially by mass percentage. After stirring until completely homogeneous dissolution, 1.0%–2.0% L-lactic acid aqueous solution was added dropwise to adjust the initial pH value to 5.2–5.4, thus obtaining the basic composite permeation solution.

3. The deep processing technology for selenium-enriched duck eggs with low salt content according to claim 1, characterized in that, The preparation method of the dynamic compensation fluid is as follows: Add 0.5%–1.0% sodium L-ascorbate and 1.0%–2.0% L-lactic acid to 97.0%–98.5% deionized water by mass percentage, and stir evenly at room temperature to obtain the dynamic compensation solution.

4. The deep processing technology for selenium-enriched duck eggs with low salt content according to claim 1, characterized in that, The basic composite permeate solution is pumped into the pressure-resistant impregnation reactor to immerse the selenium-enriched duck eggs. After sealing the pressure-resistant impregnation reactor, vacuuming and pressure holding, followed by slow pressure release, are performed sequentially to restore the reactor to normal pressure. Specifically: The basic composite permeate is pumped into the pressure-resistant impregnation reactor, and the liquid level is controlled to be 5-10 cm above the top material basket. The reactor is sealed, and the vacuum pump is started to reduce the absolute pressure inside the reactor to 0.01-0.03 MPa. The pressure is maintained for 15-30 minutes, and then the pressure relief valve is opened to slowly restore the pressure to the normal pressure state of 0.1 MPa.

5. The deep processing technology for selenium-enriched duck eggs with light salt according to claim 1, characterized in that, A portion of the total circulating liquid volume is diverted and retained, and the permeate is fed into the sensor flow cell for real-time detection. Specifically: 3.0 vol% to 5.0 vol% of the total circulating liquid is diverted into an inorganic tubular ceramic membrane module for cross-flow filtration, the retained concentrate is returned to the pressure-resistant impregnation reactor, and the permeate enters the sensor flow cell for real-time detection.

6. The deep processing technology for selenium-enriched duck eggs with light salting according to claim 1, characterized in that, The specific operation of the reaction kinetics temperature gradient control is as follows: The temperature inside the vessel is slowly raised from room temperature to 36-38℃ at a constant rate of 0.4-0.6℃ / h using a jacketed heating system, and maintained at a constant temperature throughout the process.

7. The deep processing technology for selenium-enriched duck eggs with light salt according to claim 1, characterized in that, The pH / ORP dual-lock dynamic compensation is controlled by the addition of a dynamic compensation solution. The specific operation is as follows: The dynamic compensation solution is automatically added by the dosing pump by reading the sensor values ​​of the flow cell in real time through the PID controller, which forces the pH value of the continuous phase to be anchored at 5.35 to 5.45, while maintaining the ORP value at -150 to -200mV.

8. The deep processing technology for selenium-enriched duck eggs with low salt content according to claim 1, characterized in that, The specific operation of the differential conductivity-driven stepped pulse pressurization is as follows: The control system records the absolute value of the derivative of the conductivity of the continuous phase in the sensor flow cell with respect to time in real time. When the absolute value of the derivative of the conductivity with respect to time is ≤0.01~0.05mS / (cm·h) for 20~40min, nitrogen gas is introduced into the reactor until the absolute pressure inside the reactor rises to 0.12~0.15MPa and is maintained at constant pressure for 45~75min. After the constant pressure is completed, the PID controller controls the exhaust to release pressure at a rate of 0.008 to 0.012 MPa / min to an absolute pressure of 0.1 MPa. This monitoring and pressurization / depressurization cycle is automatically repeated during the pressure release process.

9. The deep processing technology for selenium-enriched duck eggs with light salt according to claim 1, characterized in that, The total operation time is set to 48–168 hours.

10. The deep processing technology for selenium-enriched duck eggs with light salt according to claim 1, characterized in that, The cooling process involves using a refrigerant system to lower the temperature inside the reactor to 8–12°C and then maintaining the temperature under normal pressure for 192–360 hours. The high-barrier packaging material is vacuum-sealed or nitrogen-filled using polyvinylidene chloride (PVDC) high-barrier packaging material, and then sterilized in a water bath at 85–90°C for 20–30 minutes before being cooled and removed from storage.

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