Novel low-fishy-smell bitter-taste egg white powder treatment device and method

Abstract

The invention relates to a novel low-fishy-smell bitter-taste egg white powder treatment device and method, and the novel low-fishy-smell bitter-taste egg white powder treatment device comprises a heat exchanger, a first three-way pipe, an infusion pump, a jet device, an ultrasonic dispersion machine, a first coiled pipe, a second three-way pipe, a second coiled pipe and a defoaming tank which are sequentially communicated through a pipeline, the first coiled pipe and the second coiled pipe are soaked in the first hot water tank and the second hot water tank respectively, the second three-way pipe is communicated with the enzyme pipe, the jet device is communicated with the nitrogen pipe, and the defoaming tank is provided with a defoaming device. The egg white powder is used for solving the problems that existing egg white powder has fishy and bitter taste and is poor in instant solubility, dispersity and stability.

Description

Technical Field

[0001] The invention relates to a novel low-smelly and bitter egg white powder processing device and method. Background Art

[0002] Poultry egg protein is a heat-sensitive protein. It can be denatured and coagulated at a relatively low temperature (60-80 ℃) and in a relatively short time (5-8 min). High-temperature sterilization cannot be achieved, which affects the shelf life of the product and the expansion of application scenarios, becoming a bottleneck restricting the high-quality development of the poultry egg processing industry. Therefore, egg white is usually prepared into egg white powder. However, the egg white powder obtained by traditional technology has a fishy and bitter taste, and its solubility, dispersibility and stability are poor. Therefore, how to obtain egg white powder with high solubility, high stability, high dispersibility and low fishy and bitter taste has become an urgent problem to be solved in the industry. Summary of the invention

[0003] The purpose of the present invention is to provide a novel low-smelling and bitter egg white powder processing device and method, which is used to solve the problems that the existing egg white powder has a fishy and bitter taste and is poor in solubility, dispersibility and stability.

[0004] In order to solve the above problems, the technical solution of the present invention is: A novel low-smelly and bitter egg white powder processing device comprises a heat exchanger, a first three-way pipe, an infusion pump, an ejector, an ultrasonic disperser, a first serpentine pipe, a second three-way pipe, a second serpentine pipe, a third three-way pipe, a third serpentine pipe and a defoaming tank which are sequentially connected through pipelines. The first three-way pipe is connected to an alkaline enzyme pipe, the second three-way pipe is connected to a medium enzyme pipe, the third three-way pipe is connected to a ventilating enzyme pipe, the first serpentine pipe, the second serpentine pipe and the third serpentine pipe are respectively immersed in a first hot water tank, a second hot water tank and a third hot water tank, the ejector is connected to a nitrogen pipe, and the defoaming tank is equipped with a defoaming device.

[0005] The ultrasonic disperser includes a barrel, the upper and lower ends of the barrel are respectively connected with a discharge pipe and a feed pipe, an ultrasonic vibration rod is arranged in the barrel, a plurality of sleeves are fixedly connected to the ultrasonic vibration rod, a jump ring is arranged outside the sleeve, a plurality of elastic ribs are fixedly connected between the jump ring and the sleeve, and a filter is fixedly connected to the jump ring ribs.

[0006] Multiple layers of sealing rings are arranged outside the jumping ring.

[0007] A jacket is arranged outside the barrel, and the upper and lower ends of the jacket are connected with a water inlet pipe and a drain pipe.

[0008] The pipeline between the second tee pipe and the second serpentine pipe, and the pipeline between the second tee pipe and the third serpentine pipe are both connected with a stirring tank.

[0009] Electric heaters are installed at the bottom of the first hot water tank, the second hot water tank and the third hot water tank, metering pumps and flow meters are installed on the alkali enzyme tube, the intermediate enzyme tube and the wind enzyme tube, a pressure sensor and an electric pressure regulating valve are installed on the nitrogen tube, a pH sensor is installed on the first serpentine tube, the second serpentine tube and the third serpentine tube, a temperature sensor is installed on the first hot water tank, the second hot water tank and the third hot water tank, and a controller is also included. The temperature sensor, the flow meter and the pressure sensor transmit the detected signals to the controller, and the controller controls the electric heater, the metering pump and the electric pressure regulating valve.

[0010] A method for preparing a novel low-smelling and bitter egg white powder comprises the following steps: S1: Wash the eggs, dry them, dilute the egg white with an equal volume of water, heat to 50-55°C and keep for 20-30 min, then put them into a stirrer and stir at 500-600 r / min for 10-20 min for later use; S2: sending the egg white into a heat exchanger to heat up to 50-55° C., adding alkaline protease solution and sending the egg white into a nitrogen bubbling ultrasonic disperser to prepare egg white foam; S3: feeding the egg white foam into the first serpentine tube and performing enzymatic hydrolysis at 50-55°C for 10-20 min; S4: adding the neutral protease solution to the egg white foam discharged from the first serpentine tube and sending it into the second serpentine tube, and performing enzymolysis at 40-50°C for 20-40 min; S5: adding flavor protease solution to the egg white foam discharged from the second serpentine tube and then sending it into the third serpentine tube, and enzymolyzing it at 50-55°C for 20-40 min; S6: sending the egg white foam discharged from the third serpentine pipe to a defoaming tank for defoaming; S7: sending the egg white liquid obtained in step S5 into a spray dryer, and spray drying the egg white powder at an inlet air temperature of 170° C. and an outlet air temperature of 70° C.

[0011] The beneficial effects of the present invention are: 1. The ultrasonic disperser can cut and break the large nitrogen egg white bubbles into small bubbles, and at the same time break and cut the protein molecules in the egg white. With the help of the bubble bursting holes, the disulfide bonds inside the protein molecules are broken, the protein aggregates are broken, the protein structure is exposed, and it is looser, which improves the stability and solubility of the egg white protein system, accelerates the enzymatic hydrolysis of egg white, shortens the enzymatic hydrolysis time, and improves the preparation efficiency of egg white powder.

[0012] 2. Enzymatic hydrolysis can destroy the hydrophobic cavity where the fishy compounds and proteins are combined, release the fishy compounds in the protein-bound state, ensure the fishy removal effect, and at the same time improve the dispersibility of the protein and promote the rehydration and dissolution of egg white powder.

[0013] 3. During the enzymatic hydrolysis process, nitrogen bubbles are filled to achieve anaerobic enzymatic hydrolysis of egg white, ensuring that the enzymatic hydrolysis of egg white is always carried out under nitrogen protection, avoiding oxidation reaction of protein and final product during the enzymatic hydrolysis of egg white and introducing bad flavor.

[0014] 4. The enzymatic hydrolysis process of egg white is completed in the pipeline, which makes the production of egg white powder streamlined and standardized, ensuring the production efficiency of egg white powder. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will be further described below in conjunction with the accompanying drawings: Figure 1 It is a structural schematic diagram of the present invention, Figure 2 is a schematic diagram of the three-dimensional structure of the present invention, Figure 3 It is a schematic diagram of the three-dimensional structure of the ultrasonic disperser of the present invention.

[0016] Figure 4 Sensory profile of egg white powder; Figure 5 The fishy and bitter taste value of egg white powder.

[0017] In the figure: heat exchanger 1, first three-way pipe 2, infusion pump 3, ejector 4, ultrasonic disperser 5, first hot water tank 6, first serpentine pipe 7, second three-way pipe 8, flow meter 9, metering pump 10, stirring tank 11, second serpentine pipe 12, third three-way pipe 13, debubbler 14, debubbler tank 15, pH sensor 16, temperature sensor 17, electric heater 18, third hot water tank 19, third serpentine pipe 20, second hot water tank 21, electric pressure regulating valve 22, pressure sensor 23, filter screen 51, jacket 52, ultrasonic vibration rod 53, sleeve 54, elastic rib 55, sealing ring 56, jump ring 57, barrel 58. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] A novel low-smelly and bitter egg white powder processing device comprises a heat exchanger 1, a first three-way pipe 2, an infusion pump 3, an ejector 4, an ultrasonic disperser 5, a first serpentine pipe 7, a second three-way pipe 8, a second serpentine pipe 12 and a defoaming tank 15 which are sequentially connected through pipelines. The first three-way pipe 2 is connected to an alkaline enzyme pipe, the first serpentine pipe 7 and the second serpentine pipe 12 are respectively immersed in a first hot water tank 6 and a second hot water tank 21, the first hot water tank 6 and the second hot water tank 21 are used to keep the first serpentine pipe 7 and the second serpentine pipe 12 at a constant temperature, the second three-way pipe 8 is connected to an enzyme pipe, the ejector 4 is connected to a nitrogen pipe, and a defoaming tank 15 is provided with a defoaming tank 15.

[0020] A novel method for processing egg white powder with low fishy and bitter taste comprises the following steps: S1: Wash the eggs, dry them, dilute the egg white with an equal volume of water, heat to 50°C and keep for 20 minutes, then put them into a stirrer and stir at 600 r / min for 15 minutes. The viscosity of the egg white after stirring decreases and it has better fluidity. S2: sending the egg white into the heat exchanger 1, the heat exchanger 1 rapidly heats the egg white to 50°C and then enters the first three-way pipe 2 to be mixed with the alkaline protease solution, then the egg white enters the ejector 4 to be mixed with nitrogen to form bubbles and then enters the bubbling ultrasonic disperser 5, the bubbling ultrasonic disperser 5 is used to process the egg white at a power of 330 W for 15 min, and the egg white is prepared into a dense egg white foam, wherein the ratio of the total mass of the alkaline protease to the total mass of the egg white protein is 8:100; S3: sending the egg white foam into the first serpentine tube 7 and performing enzymatic hydrolysis at 50°C for 20 min, at which time the pH value of the egg white reaches 8-9; S4: the egg white foam discharged from the first serpentine tube 7 is fed into the second serpentine tube 12 after adding the neutral protease solution, and is enzymolyzed at 45°C for 30 minutes, the ratio of the total mass of the neutral protease to the egg white protein is 8:100, and the pH value of the egg white reaches 7-7.5; S5: adding flavor protease solution to the egg white foam discharged from the second serpentine tube 12 and then feeding it into the third serpentine tube 20, and performing enzymolysis at 50°C for 30 minutes, thereby removing the fishy and bitter taste of the egg white; S6: The egg white foam discharged from the third serpentine tube 20 is sent to the defoaming tank 15 for defoaming; S7: The egg white liquid obtained in step S5 is sent to a spray dryer, and spray-dried under the conditions of an inlet air temperature of 170°C and an outlet air temperature of 70°C to obtain egg white powder. The ultrasonic disperser 5 comprises a barrel 58, and the upper and lower ends of the barrel 58 are respectively connected with a discharge pipe and a feed pipe, an ultrasonic vibration rod 53 is arranged in the barrel 58, a plurality of sleeves 54 are fixedly connected to the ultrasonic vibration rod 53, a jump ring 57 is arranged on the sleeve 54, a plurality of elastic ribs 55 are fixedly connected between the jump ring 57 and the sleeve 54, and a filter screen 51 is fixedly connected to the jump ring 57 and the ribs 55. After the egg white foam mixed with nitrogen enters the barrel 58, the ultrasonic vibration rod 53 drives the elastic ribs 55, the filter screen 51 and the jump ring 57 to vibrate, and the filter screen 51 breaks the large egg white foam into fine foam during the vibration process, and at the same time breaks and cuts the protein molecules in the egg white.

[0021] A multi-layer sealing ring 56 is arranged outside the jump ring 57. The sealing ring 56 can prevent the egg white from flowing out from the gap between the jump ring 57 and the barrel 58, and ensure that the egg white foam can pass through the filter screen 51.

[0022] A jacket is provided outside the barrel 58, and the upper and lower ends of the jacket are connected to a water inlet pipe and a drain pipe. During the egg white crushing process, the egg white is kept at 50-55°C for crushing and enzymolysis.

[0023] The pipeline between the second three-way pipe 8 and the second serpentine pipe 12, and the pipeline between the second three-way pipe 8 and the third serpentine pipe 20 are both connected with a stirring tank 11. The stirring tank 11 is used to mix the egg white foam with the neutral enzymatic solution and the flavor protease solution.

[0024] An electric heater 18 is installed at the bottom of the first hot water tank 6, the second hot water tank 21 and the third hot water tank 19, and a temperature sensor 17 is installed on the first hot water tank 6, the second hot water tank 21 and the third hot water tank 19. The temperature sensor 17 detects the temperature of each tank in real time, and with the cooperation of the electric heater 18, the hot water temperature in the first hot water tank 6, the second hot water tank 21 and the third hot water tank 19 is kept within the set temperature range, so that the enzymatic hydrolysis temperature of the egg white foam in the first serpentine tube 7, the second serpentine tube 12 and the third serpentine tube 20 meets the process requirements; a metering pump 10 and a flow meter 9 are installed on the alkali enzyme tube, the medium enzyme tube and the wind enzyme tube, and the alkali is controlled by the flow meter 9 and the metering pump 10. The amount of alkaline protease liquid, neutral protease liquid and flavor protease liquid added to ensure that the egg white enzymolysis is within the set range; a pressure sensor 23 and an electric pressure regulating valve 22 are installed on the nitrogen pipe to limit the nitrogen delivery amount; a pH sensor 16 is installed on the first serpentine tube 7, the second serpentine tube 12 and the third serpentine tube 20, and the pH sensor 16 detects the pH value of the egg liquid in real time to facilitate the adjustment of the delivery amount of the alkaline protease liquid and the neutral protease liquid; a controller is also included, and the temperature sensor 17, the flow meter 9 and the pressure sensor 23 transmit the detected signal to the controller, and the controller controls the electric heater 18, the metering pump 10 and the electric pressure regulating valve 22. The controller is a PLC controller, which makes the egg white enzymolysis automatic, and when the egg white enzymolysis parameters and time meet the process requirements, the enzymolysis quality is ensured.

[0025] Comparative Example 1 Based on Example 1, without ultrasonic treatment, S2: sending the egg white into the heat exchanger 1, the heat exchanger 1 rapidly heats the egg white to 50°C, and then the egg white enters the first three-way pipe 2 to be mixed with the alkaline protease solution, and then directly proceeds to step S3; Comparative Example 2 Based on Example 1, a numerically controlled ultrasonic generator (KQ-800DE, Kunshan Ultrasonic Instrument Co., Ltd.) was used for treatment. S2: the egg white is sent to the heat exchanger 1, and the heat exchanger 1 quickly heats the egg white to 50°C, and the egg white is treated at a power of 300 W for 15 minutes, and then enters the first three-way pipe 2 to be mixed with the alkaline protease solution and then directly proceeds to step S3; Experimental methods 1. Detection of egg white powdery and bitter taste The sensory panel consisted of 10 members (6 men and 4 women) with rich experience in sensory evaluation and the ability to identify different flavors. The intensity of the fishy and bitter taste of each egg white powder sample was scored in the range of 0-10 points, with 0 representing no fishy and bitter taste at all and the higher the score, the stronger the fishy and bitter taste. Before evaluating the next sample, the nasal cavity was cleansed by sniffing pure water to avoid affecting the sniffing result of the next sample. Each sample was tested 3 times.

[0026] 2. Detection of key flavor substances in egg white powder The volatiles in egg white powder were extracted by headspace solid phase microextraction (HS-SPME). 1 g of sample was weighed and placed in a 20 mL headspace bottle. The solid phase microextraction fiber (DVB / CAR / PDMS, 50 / 30 μm) was placed in the headspace bottle containing egg white powder and kept in a 60°C water bath for 60 min to extract volatile substances. Subsequently, the fiber head enriched with volatile substances was transferred to the injection port and analyzed at 250°C for 5 min for GC-MS analysis. The flavor was analyzed in splitless mode by a gas chromatography-mass spectrometer (GCMS-QP2010, Shimadzu) equipped with DB-5MS (60 m× 0.32 mm× 1 μm). The gas phase parameters were set as follows: the injection port temperature was 250°C, the column carrier gas was helium, and the constant flow rate was 1.5 mL / min. The column temperature program was set as follows: the initial temperature was 40 °C for 2 min, then the temperature was increased to 200 °C at a rate of 4 °C / min, and then to 230 °C at a rate of 5 °C / min. The mass spectra in MS-EI ionization mode were recorded at an ionization energy of 70 eV, and the ion source temperature was set to 230 °C. Full scan acquisition was used in the range of 33-350 amu. Each sample was measured three times. Volatile compounds were identified by mass spectrometry (MS). The mass spectral peaks were searched and compared with the NIST 17 library, and the matching index (SI) greater than or equal to 70 was considered significant. The linear retention index (RI) of each compound was calculated by normal alkanes (C7-C40), and the compounds were determined by comparison with the retention index in the database. Cyclohexanone was selected as the internal standard for semi-quantification of volatile compounds. Cyclohexanone was diluted 50,000 times (v / v) with methanol solution, and 5 μL of internal standard (concentration of 18.94 ng / μL) was added to each quantitative sample. The content of aromatic compounds was calculated based on the ratio of cyclohexanone peak area to concentration. The aroma activity value (OAV) refers to the ratio of the concentration of each volatile substance in water to its respective threshold value. Compounds with OAV ≥ 1 are considered to be contributors to the aroma characteristics of the sample. Each sample was measured three times.

[0027] 3. Aroma reorganization and loss experiments and identification of key fishy and bitter substances To further identify the key bitter and fishy compounds in egg white powder, 16 substances with OAV≥1 were reconstructed according to the quantitative results, and the samples were compared with the bitter and fishy taste of egg white powder after being equilibrated at room temperature for 1 h. In order to determine the effect of each and every type of aromatic active compound on the overall bitter and fishy taste, a total of 19 missing models were established. The difference between each omitted model and the fully reconstructed model was evaluated by a triangular test. If 8 people answered correctly, the result was significant (α≤0.05); if 9 people answered correctly, it was extremely significant (α≤0.01); if 10 people answered correctly, it was very significant (α≤0.001).

[0028] 2. Results: 1. Identify the powdery and bitter substances in egg white: The egg white powder obtained by spray drying was subjected to sensory evaluation. Figure 4 As shown in Table 1, the fishy and bitter taste of egg white powder (Comparative Example 1) is mainly manifested as "fishy", "grassy" and "oil / malt". The key flavor substances identified by GC-MS are shown in Table 1. There are 16 substances with OAV≥1, including 6 aldehydes, 5 terpenes, 3 alcohols, and 1 ester and 1 ketone each. These substances have a prominent contribution to the flavor of egg white powder. The 16 identified key flavor substances (OAV≥1) were mixed according to the measured concentration to form an aroma reconstruction model and 19 aroma loss models to study the contribution of a certain or a certain type of volatile compound to the fishy and bitter taste of egg white powder. The results are shown in Table 2, which further clarified that octanal, nonanal, 1-octen-3-ol and geranyl acetone are the key fishy and bitter substances of egg white powder.

[0029] Table 1 Key flavor substances in egg white powder

[0030] Table 2 Aroma reorganization and aroma loss experiments

[0031] Note: a is the number of people who made correct judgments through the triangular test; b is significance, * indicates significant (α ≤ 0.05), ** indicates extremely significant (α ≤ 0.01), *** indicates very significant (α ≤ 0.001), and ns indicates not significant.

[0032] 2. Sensory fishy and bitter taste and content of fishy and bitter substances Flavor is an important factor affecting food consumption, and fishy smell seriously affects the sensory quality of egg white powder. Figure 5As shown, when the egg variety and freshness are consistent, the egg white powder prepared by the embodiment of the present invention has excellent sensory quality, that is, the egg fishy bitterness is the lowest. Existing data show that octanal, nonanal, 1-octen-3-ol and geranyl acetone are the key fishy and bitter substances in egg white powder. In addition to sensory evaluation, it is more convincing to verify the de-fishy and bitter effect of the present invention by measuring the changes in the content and proportion of fishy and bitter substances. The changes in the content and proportion of fishy and bitter substances in the embodiments and comparative examples are shown in Table 3. It is found that after being treated with the present invention, the content of fishy and bitter substances in the egg white powder is significantly reduced. This result shows that the influence of fishy and bitter substances on the overall flavor of egg white powder is reduced, that is, the present invention achieves a significant reduction in the fishy and bitter taste of egg white powder.

[0033] Table 3 Contents of key fishy and bitter substances in the examples and comparative examples

[0034] The contents described in the embodiments of this specification are merely an enumeration of the implementation forms of the inventive concept. The protection scope of the present invention should not be regarded as limited to the specific forms described in the embodiments. The protection scope of the present invention also extends to equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A novel low-smelling and bitter egg white powder processing device, characterized in that: The invention comprises a heat exchanger (1), a first three-way pipe (2), an infusion pump (3), an ejector (4), an ultrasonic disperser (5), a first serpentine pipe (7), a second three-way pipe (8), a second serpentine pipe (12), a third three-way pipe (13), a third serpentine pipe (20) and a defoaming tank (15) which are sequentially connected through pipelines. The first three-way pipe (2) is connected to an alkaline enzyme pipe, the second three-way pipe (8) is connected to a medium enzyme pipe, the third three-way pipe (13) is connected to a ventilated enzyme pipe, the first serpentine pipe (7), the second serpentine pipe (12) and the third serpentine pipe (20) are respectively immersed in a first hot water tank (6), a second hot water tank (21) and a third hot water tank (19), the ejector (4) is connected to a nitrogen pipe, and a defoaming tank (15) is provided with a defoaming tank (14).

2. A novel low-smelly and bitter egg white powder processing device according to claim 1, characterized in that: The ultrasonic disperser (5) comprises a barrel (58), wherein the upper and lower ends of the barrel (58) are respectively connected to a discharge pipe and a feed pipe, an ultrasonic vibration rod (53) is arranged in the barrel (58), a plurality of sleeves (54) are fixedly connected to the ultrasonic vibration rod (53), a jump ring (57) is arranged on the sleeve (54), a plurality of elastic ribs (55) are fixedly connected between the jump ring (57) and the sleeve (54), and a filter screen (51) is fixedly connected to the jump ring (57) and the ribs (55).

3. A novel low-smelly and bitter egg white powder processing device according to claim 2, characterized in that: A multi-layer sealing ring (56) is arranged outside the jumping ring (57).

4. A novel low-smelly and bitter egg white powder processing device according to claim 2, characterized in that: A jacket is provided outside the barrel (58), and the upper and lower ends of the jacket are connected to a water inlet pipe and a drain pipe.

5. A novel low-smelly and bitter egg white powder processing device according to any one of claims 1 to 4, characterized in that: The pipeline between the second three-way pipe (8) and the second serpentine pipe (12), and the pipeline between the second three-way pipe (8) and the third serpentine pipe (20) are both connected to a stirring tank.

6. A novel low-smelly and bitter egg white powder processing device according to any one of claims 1 to 4, characterized in that: An electric heater (18) is installed at the bottom of the first hot water tank (6), the second hot water tank (21) and the third hot water tank (19); a metering pump (10) and a flow meter (9) are installed on the alkaline enzyme tube, the intermediate enzyme tube and the wind enzyme tube; a pressure sensor (23) and an electric pressure regulating valve (22) are installed on the nitrogen tube; a pH sensor (16) is installed on the first serpentine tube (7), the second serpentine tube (12) and the third serpentine tube (20); a temperature sensor (17) is installed on the first hot water tank (6), the second hot water tank (21) and the third hot water tank (19); and a controller is also included. The temperature sensor (17), the flow meter (9) and the pressure sensor (23) transmit detected signals to the controller, and the controller controls the electric heater (18), the metering pump (10) and the electric pressure regulating valve (22).

7. A method for preparing low-smelly bitter egg white powder using the device according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: Wash the eggs, dry them, dilute the egg white with an equal volume of water, heat to 50-55°C and keep for 20-30 minutes, then put them into a stirrer and stir at 500-600 r / min for 10-20 minutes for later use; S2: sending the egg white into a heat exchanger (1) to raise the temperature to 50-55°C, adding alkaline protease solution and sending the egg white into a nitrogen bubbling ultrasonic disperser (5) to prepare egg white foam; S3: feeding the egg white foam into the first serpentine tube (7) and performing enzymatic hydrolysis at 50-55°C for 10-20 min; S4: adding the neutral protease solution to the egg white foam discharged from the first serpentine tube (7) and then sending it to the second serpentine tube (12), and performing enzymolysis at 40-50°C for 20-40 minutes; S5: adding the flavor protease solution to the egg white foam discharged from the second serpentine tube (12) and then feeding it into the third serpentine tube (20), and performing enzymolysis at 50-55°C for 20-40 minutes; S6: sending the egg white foam discharged from the third serpentine tube (20) to the defoaming tank (15) for defoaming; S7: sending the egg white liquid obtained in step S5 into a spray dryer, and spray drying the egg white powder at an inlet air temperature of 170° C. and an outlet air temperature of 70° C.

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