A method for stabilizing a high concentration amino acid surfactant transparent concentrate

Abstract

The application discloses a kind of high-concentration amino acid surfactant transparent concentrate stabilization method, comprising the following steps: step one, raw material precision weighing and pretreatment, step two, first low-temperature assisted dispersion, step three, second step gradient temperature control dissolving, step four, three-dimensional synergistic stabilization treatment, step five, gradient pH precision control, step six, low-temperature homogenization curing, step seven, product filtration and detection;The application constructs the stabilization method of step-by-step gradient temperature control dissolving and three-dimensional synergistic stabilization system, different from the prior art one-step mixing, single thickening stabilization, by batch feeding, gradient temperature control dissolving, avoid high-concentration amino acid surfactant due to local concentration too high, temperature sudden change leads to molecular aggregation crystallization, from source inhibit turbidity and phase separation.

Description

Technical Field

[0001] This invention relates to the fields of cosmetic raw materials and daily chemical surfactants, specifically a method for stabilizing a high-concentration amino acid surfactant transparent concentrate. Background Technology

[0002] Amino acid surfactants are anionic / amphoionic surfactants synthesized from natural amino acids. They possess advantages such as being gentle on the skin, having good biodegradability, low irritation, and high foaming properties, making them a core ingredient in high-end shampooing, cleansing, and skincare products. Currently, the industry urgently needs high-concentration, transparent concentrates of amino acid surfactants to reduce storage and transportation costs and improve formulation compatibility. However, in high-concentration systems, amino acid surfactants are prone to problems such as molecular aggregation, crystallization, turbidity, stratification, and poor heat and cold resistance. Existing technologies cannot achieve efficient and stable control.

[0003] Existing technology CN107358064A: This technology belongs to the field of biomedical data analysis. It uses a two-layer three-dimensional random forest algorithm to predict the impact of amino acid variation on protein structural stability. It only focuses on the correlation analysis between protein biological structure and amino acid variation, and does not involve the formulation, preparation and stabilization regulation of amino acid surfactants in the daily chemical field. It has no technical connection with the stabilization of high-concentration amino acid surfactant concentrate.

[0004] Existing technology CN111983051A: This technology belongs to the field of amino acid analysis and detection. It determines the stable nitrogen isotope ratio of amino acids by derivatization-gas chromatography-isotope ratio mass spectrometry. It only focuses on the physicochemical detection method of amino acids and does not involve the synthesis, concentration and stabilization process of amino acid surfactants. It cannot solve the defects of transparency and stability in high-concentration systems.

[0005] Existing technology CN114177110A: This technology belongs to the field of cosmetic end products. It prepares facial cleansing cream by compounding amino acid surfactants, thickeners and stabilizers. The concentration of amino acid surfactants is only 15wt% to 25wt%, which belongs to a low to medium concentration system. The final product is a pearlescent cream rather than a transparent concentrate. The thickeners (cetyl hydroxyethyl cellulose, xanthan gum) and stabilizers (sodium hydroxypropyl starch phosphate) used in this technology are only suitable for cream systems. Direct application to high-concentration transparent concentrates will cause the system to become turbid, the viscosity to increase sharply and the phase to separate, and it is impossible to achieve transparency and long-term stability at high concentrations.

[0006] The current technical problems with high-concentration amino acid surfactant transparent concentrates are:

[0007] When the concentration of amino acid surfactant is ≥30wt%, the intermolecular hydrogen bonds and hydrophobic interactions are excessively enhanced, and micelles aggregate to form microcrystals, resulting in a cloudy and opaque concentrate that loses its application value as a transparent raw material. It has poor temperature adaptability, easily separates into layers and separates into water under heat resistance at 48℃, and easily crystallizes and solidifies under cold resistance at -20℃. It cannot be restored to a transparent and uniform state after returning to room temperature. Long-term storage at room temperature is prone to viscosity drift, phase separation, and microbial contamination. The amount of preservative added exceeds the standard and does not meet the safety standards for daily chemical raw materials. Summary of the Invention

[0008] The purpose of this invention is to provide a stabilization method for a high-concentration amino acid surfactant transparent concentrate, so as to solve the problems mentioned in the background art.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a method for stabilizing a high-concentration amino acid surfactant transparent concentrate, comprising the following steps:

[0010] Step 1: Accurate weighing and pretreatment of raw materials: Weigh the amino acid surfactant complex, multi-component cosolvent, ion regulator, nano stabilizer, pH regulator, and preservative by weight percentage, wherein the total amount of preservative added is ≤1wt%. Pass the solid raw materials through a 100-mesh sieve and filter the liquid raw materials to remove impurities.

[0011] Step 2, First step: Low temperature co-solubilization and dispersion: Add deionized water to the reactor, heat to 35℃~40℃, turn on the stirrer, control the speed to 120r / min~150r / min, add multi-component co-solubilizer and ion regulator, stir for 10min~15min until completely dissolved, and form a uniform aqueous dispersion substrate.

[0012] Step 3, Second Step Gradient Temperature Control Dissolution: Keep the stirring speed constant, add the amino acid surfactant complex component in 3 equal portions, with an interval of 8 min to 10 min between each addition, and stir for 12 min to 15 min after each addition; after the first addition, maintain the temperature at 35℃ to 40℃, after the second addition, raise the temperature to 42℃ to 45℃, and after the third addition, raise the temperature to 48℃ to 50℃. Avoid sudden temperature increases throughout the process until the amino acid surfactant is completely dissolved.

[0013] Step 4, Three-dimensional synergistic stabilization treatment: Maintain the temperature at 48℃~50℃, reduce the stirring speed to 80r / min~100r / min, add the nano stabilizer, and stir for 20min~25min to ensure that the nano stabilizer is uniformly dispersed in the system;

[0014] Step 5, precise pH gradient control: While maintaining stirring, slowly add the pH adjuster to adjust the pH of the system to 5.5-6.5, and stir for 15-20 minutes;

[0015] Step 6, Low-temperature homogenization and maturation: Cool the system to 25℃~30℃, use a high-pressure homogenizer for homogenization, control the homogenization pressure to 30MPa~40MPa, homogenize 2~3 times, and then transfer it to a maturation kettle and seal it for maturation at a constant temperature of 25℃ for 24h~48h.

[0016] Step 7, Finished Product Filtration and Testing: The matured concentrate is filtered through a 0.22μm microporous membrane to obtain a high-concentration amino acid surfactant transparent concentrate.

[0017] Furthermore, the amino acid surfactant complex is composed of sodium lauroyl glutamate, sodium lauroyl glycinate, and sodium cocoyl glycinate in a mass ratio of 3:3:4, with a total concentration of 30wt% to 50wt%.

[0018] Furthermore, the multi-component cosolvent is composed of 1,3-propanediol, trehalose, and betaine in a mass ratio of 5:2:3, and the amount added is 8wt% to 15wt%.

[0019] Furthermore, the ion regulator is a compound of sodium citrate and sodium chloride in a mass ratio of 9:1, and the amount added is 1wt% to 4wt%.

[0020] Furthermore, the nano-stabilizer is a hydroxypropyl cellulose nano-dispersion with a solid content of 2 wt% and an addition amount of 0.5 wt% to 2 wt%.

[0021] Furthermore, the pH adjuster is a 10wt% citric acid solution; the preservative is a compound of methylparaben, ethylparaben, and glyceryl caprylate in a mass ratio of 2:1:2, with a total addition amount of 0.1wt% to 1wt%.

[0022] Furthermore, in step two, the stirring speed is 130 r / min and the stirring time is 12 min; in step three, the interval between each addition is 9 min, and the stirring is 13 min after each addition. The temperature of the first addition is 38℃, the temperature of the second addition is 43℃, and the temperature of the third addition is 49℃.

[0023] Furthermore, in step four, the stirring speed is 90 r / min and the stirring time is 22 min; in step five, the stirring time is 18 min; in step six, the homogenization pressure is 35 MPa, the homogenization is performed 3 times, the maturation temperature is 25℃, and the maturation time is 36 h.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] This invention presents a stabilization method for constructing a stepwise gradient temperature-controlled dissolution and three-dimensional synergistic stabilization system. Unlike the one-step mixing and single thickening stabilization methods of existing technologies, this method uses batch feeding and gradient temperature increase to dissolve the system, avoiding molecular aggregation and crystallization caused by excessively high local concentrations and sudden temperature changes of high-concentration amino acid surfactants. This suppresses turbidity and phase separation from the source.

[0026] This invention employs a three-dimensional synergistic stabilization system of multiple cosolvents, ion regulators, and nano stabilizers. The cosolvents disrupt molecular hydrogen bonds, the ion regulators balance the system charge, and the nano stabilizers provide steric hindrance. These three actions work together to maintain the uniform dispersion of micelles at high concentrations, achieving long-term transparency and uniformity in high-concentration systems of 30wt% to 50wt%. This overcomes the technical limitations of existing technologies, which are only applicable to low and medium concentration pastes.

[0027] This invention eliminates internal molecular stress and optimizes micelle size distribution through gradient pH control and low-temperature homogenization and maturation processes, thereby significantly improving the heat and cold resistance of the concentrate.

[0028] This invention strictly controls the total amount of preservatives added to ≤1wt%, which meets the safety standards for daily chemical raw materials. The pH value of the system is 5.5 to 6.5, which is compatible with human skin. It is gentle and non-irritating and can be directly applied to high-end facial cleansing, washing and care, and skin care formulas, thus broadening the application scenarios of amino acid surfactants. Attached Figure Description

[0029] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0031] Please see Figure 1 This invention provides a method for stabilizing a high-concentration amino acid surfactant transparent concentrate, comprising the following steps:

[0032] Step 1: Accurate weighing and pretreatment of raw materials: Weigh the amino acid surfactant complex, multi-component cosolvent, ion regulator, nano stabilizer, pH regulator, and preservative by weight percentage, wherein the total amount of preservative added is ≤1wt%. Pass the solid raw materials through a 100-mesh sieve and filter the liquid raw materials to remove impurities.

[0033] Step 2, First step: Low temperature co-solubilization and dispersion: Add deionized water to the reactor, heat to 35℃~40℃, turn on the stirrer, control the speed to 120r / min~150r / min, add multi-component co-solubilizer and ion regulator, stir for 10min~15min until completely dissolved, and form a uniform aqueous dispersion substrate.

[0034] Step 3, Second Step Gradient Temperature Control Dissolution: Keep the stirring speed constant, add the amino acid surfactant complex component in 3 equal portions, with an interval of 8 min to 10 min between each addition, and stir for 12 min to 15 min after each addition; after the first addition, maintain the temperature at 35℃ to 40℃, after the second addition, raise the temperature to 42℃ to 45℃, and after the third addition, raise the temperature to 48℃ to 50℃. Avoid sudden temperature increases throughout the process until the amino acid surfactant is completely dissolved.

[0035] Step 4, Three-dimensional synergistic stabilization treatment: Maintain the temperature at 48℃~50℃, reduce the stirring speed to 80r / min~100r / min, add the nano stabilizer, and stir for 20min~25min to ensure that the nano stabilizer is uniformly dispersed in the system;

[0036] Step 5, precise pH gradient control: While maintaining stirring, slowly add the pH adjuster to adjust the pH of the system to 5.5-6.5, and stir for 15-20 minutes;

[0037] Step 6, Low-temperature homogenization and maturation: Cool the system to 25℃~30℃, use a high-pressure homogenizer for homogenization, control the homogenization pressure to 30MPa~40MPa, homogenize 2~3 times, and then transfer it to a maturation kettle and seal it for maturation at a constant temperature of 25℃ for 24h~48h.

[0038] Step 7, Finished Product Filtration and Testing: The matured concentrate is filtered through a 0.22μm microporous membrane to obtain a high-concentration amino acid surfactant transparent concentrate.

[0039] Furthermore, the amino acid surfactant complex is composed of sodium lauroyl glutamate, sodium lauroyl glycinate, and sodium cocoyl glycinate in a mass ratio of 3:3:4, with a total concentration of 30wt% to 50wt%.

[0040] The multi-component cosolvent is composed of 1,3-propanediol, trehalose, and betaine in a mass ratio of 5:2:3, and the amount added is 8wt% to 15wt%.

[0041] The ion regulator is a compound of sodium citrate and sodium chloride in a mass ratio of 9:1, and the amount added is 1wt% to 4wt%.

[0042] The nano stabilizer is a hydroxypropyl cellulose nano dispersion with a solid content of 2 wt% and an addition amount of 0.5 wt% to 2 wt%.

[0043] The pH adjuster is a 10wt% citric acid solution; the preservative is a compound of methylparaben, ethylparaben, and glyceryl caprylate in a mass ratio of 2:1:2, with a total addition amount of 0.1wt% to 1wt%.

[0044] In step two, the stirring speed is 130 r / min and the stirring time is 12 min; in step three, the interval between each addition is 9 min, and the stirring time is 13 min after each addition. The temperature of the first addition is 38℃, the temperature of the second addition is 43℃, and the temperature of the third addition is 49℃.

[0045] In step four, the stirring speed is 90 r / min and the stirring time is 22 min; in step five, the stirring time is 18 min; in step six, the homogenization pressure is 35 MPa, the homogenization is performed 3 times, the maturation temperature is 25℃, and the maturation time is 36 h.

[0046] Example 1: Stabilization preparation of a 30wt% high-concentration amino acid surfactant transparent concentrate

[0047] Raw material composition (by weight):

[0048] The composition includes: 30wt% amino acid surfactant complex (9wt% sodium lauroyl glutamate, 9wt% sodium lauroyl glycinate, 12wt% sodium cocoyl glycinate), 8wt% multi-component cosolvent (4wt% 1,3-propanediol, 1.6wt% trehalose, 2.4wt% betaine), 1wt% ion regulator (0.9wt% sodium citrate, 0.1wt% sodium chloride), 0.5wt% nano stabilizer, appropriate amount of pH adjuster (10wt% citric acid solution), 0.1wt% preservative (0.04wt% methylparaben, 0.02wt% ethylparaben, 0.04wt% glyceryl caprylate), and the balance being deionized water.

[0049] Preparation steps:

[0050] Step 1, Raw material pretreatment: Amino acid surfactant, ion regulator, and preservative are passed through a 100-mesh sieve, and multi-component cosolvent and nano stabilizer are filtered through a 0.45μm filter membrane to remove impurities. They are then weighed precisely according to the formula.

[0051] Step 2, Low-temperature co-solubilization and dispersion: Add deionized water to the reactor, heat to 38°C, start stirring at 130 r / min, add multi-component co-solubilizer and ion regulator, stir for 12 min until completely dissolved, and form an aqueous dispersion substrate;

[0052] Step 3, Gradient temperature control dissolution: Maintain a stirring speed of 130 r / min, add the amino acid surfactant complex in three equal portions, with a 9-minute interval between each addition, and stir for 13 minutes after each addition; maintain 38℃ for the first addition, raise the temperature to 43℃ for the second addition, and raise the temperature to 49℃ for the third addition, and stir until completely dissolved, with no particles or flocculent matter.

[0053] Step 4, Synergistic Stabilization Treatment: Maintain 49℃, reduce stirring speed to 90r / min, add nano stabilizer, and stir for 22min until uniformly dispersed;

[0054] Step 5, pH adjustment: Slowly add 10wt% citric acid solution to adjust the pH of the system to 5.8, and stir for 18 minutes until the charge is uniform;

[0055] Step 6: Low-temperature homogenization and maturation: Cool down to 28℃, homogenize 3 times under 35MPa pressure in a high-pressure homogenizer, and then transfer to a maturation kettle for constant temperature and sealing maturation at 25℃ for 36 hours.

[0056] Step 7, Filtration and Detection: After filtration through a 0.22μm microporous membrane, a 30wt% transparent concentrate was obtained.

[0057] Example 2: Stabilization preparation of a 40wt% high-concentration amino acid surfactant transparent concentrate

[0058] Raw material composition (by weight):

[0059] The composition includes: 40wt% amino acid surfactant complex (12wt% sodium lauroyl glutamate, 12wt% sodium lauroyl glycinate, 16wt% sodium cocoyl glycinate), 12wt% multi-component cosolvent (6wt% 1,3-propanediol, 2.4wt% trehalose, 3.6wt% betaine), 2.5wt% ion modifier (2.25wt% sodium citrate, 0.25wt% sodium chloride), 1.2wt% nano stabilizer, appropriate amount of pH adjuster (10wt% citric acid solution), 0.5wt% preservative (0.2wt% methylparaben, 0.1wt% ethylparaben, 0.2wt% glyceryl caprylate), and the balance being deionized water.

[0060] Preparation steps:

[0061] Step 1, Raw material pretreatment: Amino acid surfactant, ion regulator, and preservative are passed through a 100-mesh sieve, and multi-component cosolvent and nano stabilizer are filtered through a 0.45μm filter membrane to remove impurities. They are then weighed precisely according to the formula.

[0062] Step 2, Low-temperature co-solubilization and dispersion: Add deionized water to the reactor, heat to 38°C, start stirring at 130 r / min, add multi-component co-solubilizer and ion regulator, stir for 12 min until completely dissolved, and form an aqueous dispersion substrate;

[0063] Step 3, Gradient temperature control dissolution: Maintain a stirring speed of 130 r / min, add the amino acid surfactant complex in three equal portions, with a 9-minute interval between each addition, and stir for 13 minutes after each addition; maintain 38℃ for the first addition, raise the temperature to 43℃ for the second addition, and raise the temperature to 49℃ for the third addition, and stir until completely dissolved, with no particles or flocculent matter.

[0064] Step 4, Synergistic Stabilization Treatment: Maintain 49℃, reduce stirring speed to 90r / min, add nano stabilizer, and stir for 22min until uniformly dispersed;

[0065] Step 5, pH adjustment: Slowly add 10wt% citric acid solution to adjust the pH of the system to 5.8, and stir for 18 minutes until the charge is uniform;

[0066] Step 6: Low-temperature homogenization and maturation: Cool down to 28℃, homogenize 3 times under 35MPa pressure in a high-pressure homogenizer, and then transfer to a maturation kettle for constant temperature and sealing maturation at 25℃ for 48 hours.

[0067] Step 7, Filtration and Detection: After filtration through a 0.22μm microporous membrane, a 30wt% transparent concentrate was obtained.

[0068] Example 3: Stabilization preparation of a 50wt% high-concentration amino acid surfactant transparent concentrate

[0069] Raw material composition (by weight):

[0070] The composition includes: 50wt% amino acid surfactant complex (15wt% sodium lauroyl glutamate, 15wt% sodium lauroyl glycinate, 20wt% sodium cocoyl glycinate), 15wt% multi-component cosolvent (7.5wt% 1,3-propanediol, 3wt% trehalose, 4.5wt% betaine), 4wt% ion regulator (3.6wt% sodium citrate, 0.4wt% sodium chloride), 2wt% nano stabilizer, appropriate amount of pH adjuster (10wt% citric acid solution), 1wt% preservative (0.4wt% methylparaben, 0.2wt% ethylparaben, 0.4wt% glyceryl caprylate), and the balance being deionized water.

[0071] Preparation steps:

[0072] Step 1, Raw material pretreatment: Amino acid surfactant, ion regulator, and preservative are passed through a 100-mesh sieve, and multi-component cosolvent and nano stabilizer are filtered through a 0.45μm filter membrane to remove impurities. They are then weighed precisely according to the formula.

[0073] Step 2, Low-temperature co-solubilization and dispersion: Add deionized water to the reactor, heat to 38°C, start stirring at 130 r / min, add multi-component co-solubilizer and ion regulator, stir for 12 min until completely dissolved, and form an aqueous dispersion substrate;

[0074] Step 3, Gradient temperature control dissolution: Maintain a stirring speed of 130 r / min, add the amino acid surfactant complex in three equal portions, with a 9-minute interval between each addition, and stir for 13 minutes after each addition; maintain 38℃ for the first addition, raise the temperature to 43℃ for the second addition, and raise the temperature to 49℃ for the third addition, and stir until completely dissolved, with no particles or flocculent matter.

[0075] Step 4, Synergistic Stabilization Treatment: Maintain 49℃, reduce stirring speed to 90r / min, add nano stabilizer, and stir for 22min until uniformly dispersed;

[0076] Step 5, pH adjustment: Slowly add 10wt% citric acid solution to adjust the pH of the system to 5.8, and stir for 18 minutes until the charge is uniform;

[0077] Step 6: Low-temperature homogenization and maturation: Cool down to 28℃, homogenize 3 times under 35MPa pressure in a high-pressure homogenizer, and then transfer to a maturation kettle for constant temperature and sealing maturation at 25℃ for 48 hours.

[0078] Step 7, Filtration and Detection: After filtration through a 0.22μm microporous membrane, a 30wt% transparent concentrate was obtained.

[0079] Comparative Example 1: Concentrate prepared according to the existing technology in CN114177110A

[0080] Raw material composition:

[0081] Using the formulation of CN114177110A, 15wt% to 25wt% amino acid surfactant, thickener (cetyl hydroxyethyl cellulose, xanthan gum, sodium chloride, stearic acid), stabilizer (sodium hydroxypropyl starch phosphate, hydroxypropyl cellulose), and the rest are the same as in Example 2, a 40wt% concentrate was prepared.

[0082] Preparation steps:

[0083] One-step mixing method: Mix all raw materials, heat to 80℃~85℃ to dissolve, cool to 40℃ and remove from the pot. There is no gradient dissolution or homogenization cooking step.

[0084] Comparative Example 2: Preparation of Concentrate without Nano-Stabilizer

[0085] The raw materials are the same as in Example 2, except that the nano stabilizer is removed, and the rest of the preparation steps are the same.

[0086] Comparative Example 3: Preparation of concentrated solution by one-step dissolution method

[0087] The raw materials are the same as in Example 2. The amino acid surfactant is added at once and heated to 50°C in one step to dissolve. There are no gradient feeding or gradient heating steps. The rest of the process is the same.

[0088] Performance Comparison Table of Examples 1-3 and Comparative Examples 1-3:

[0089] Effect verification analysis:

[0090]

[0091] 1. Transparency comparison: Examples 1 to 3 of the present invention still maintain high light transmittance and uniform transparency at high concentrations of 30wt% to 50wt%; Comparative Example 1 uses existing facial cleanser technology, which directly leads to turbidity of the system; Comparative Example 2 has no nano stabilizer, and micelle aggregation leads to a decrease in light transmittance; Comparative Example 3 is dissolved in one step, and the local concentration is too high, resulting in crystallization and extremely poor transparency.

[0092] 2. Stability Comparison: The examples showed excellent stability with no stratification, crystallization, or turbidity during long-term storage at room temperature, while the comparative examples 1 to 3 all showed varying degrees of phase separation, crystallization, and stratification, failing to meet the stability requirements of high-concentration concentrates.

[0093] 3. Safety Comparison: The total preservative content in the embodiments of the present invention is ≤1wt%, which meets the daily chemical safety standards, and the pH value is 5.5~6.5, which is mild and skin-friendly; the comparative example has no safety dosage control, and the system is more irritating than the present invention.

[0094] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for stabilizing a high-concentration amino acid surfactant transparent concentrate, characterized in that: Includes the following steps: Step 1: Accurate weighing and pretreatment of raw materials: Weigh the amino acid surfactant complex, multi-component cosolvent, ion regulator, nano stabilizer, pH regulator, and preservative by weight percentage, wherein the total amount of preservative added is ≤1wt%. Pass the solid raw materials through a 100-mesh sieve and filter the liquid raw materials to remove impurities. Step 2, First step: Low temperature co-solubilization and dispersion: Add deionized water to the reactor, heat to 35℃~40℃, turn on the stirrer, control the speed to 120r / min~150r / min, add multi-component co-solubilizer and ion regulator, stir for 10min~15min until completely dissolved, and form a uniform aqueous dispersion substrate. Step 3, Second Step Gradient Temperature Control Dissolution: Keep the stirring speed constant, add the amino acid surfactant complex component in 3 equal portions, with an interval of 8 min to 10 min between each addition, and stir for 12 min to 15 min after each addition; after the first addition, maintain the temperature at 35℃ to 40℃, after the second addition, raise the temperature to 42℃ to 45℃, and after the third addition, raise the temperature to 48℃ to 50℃. Avoid sudden temperature increases throughout the process until the amino acid surfactant is completely dissolved. Step 4, Three-dimensional synergistic stabilization treatment: Maintain the temperature at 48℃~50℃, reduce the stirring speed to 80r / min~100r / min, add the nano stabilizer, and stir for 20min~25min to ensure that the nano stabilizer is uniformly dispersed in the system; Step 5, precise pH gradient control: While maintaining stirring, slowly add the pH adjuster to adjust the pH of the system to 5.5-6.5, and stir for 15-20 minutes; Step 6, Low-temperature homogenization and maturation: Cool the system to 25℃~30℃, use a high-pressure homogenizer for homogenization, control the homogenization pressure to 30MPa~40MPa, homogenize 2~3 times, and then transfer it to a maturation kettle and seal it for maturation at a constant temperature of 25℃ for 24h~48h. Step 7, Finished Product Filtration and Testing: The matured concentrate is filtered through a 0.22μm microporous membrane to obtain a high-concentration amino acid surfactant transparent concentrate.

2. The stabilization method for a high-concentration amino acid surfactant transparent concentrate according to claim 1, characterized in that: The amino acid surfactant complex is composed of sodium lauroyl glutamate, sodium lauroyl glycinate, and sodium cocoyl glycinate in a mass ratio of 3:3:4, with a total concentration of 30wt% to 50wt%.

3. The stabilization method for a high-concentration amino acid surfactant transparent concentrate according to claim 1, characterized in that: The multi-component cosolvent is composed of 1,3-propanediol, trehalose, and betaine in a mass ratio of 5:2:3, and the amount added is 8wt% to 15wt%.

4. The stabilization method for a high-concentration amino acid surfactant transparent concentrate according to claim 1, characterized in that: The ion regulator is a compound of sodium citrate and sodium chloride in a mass ratio of 9:1, and the amount added is 1wt% to 4wt%.

5. The stabilization method for a high-concentration amino acid surfactant transparent concentrate according to claim 1, characterized in that: The nano-stabilizer is a hydroxypropyl cellulose nano-dispersion with a solid content of 2 wt% and an addition amount of 0.5 wt% to 2 wt%.

6. The stabilization method for a high-concentration amino acid surfactant transparent concentrate according to claim 1, characterized in that: The pH adjuster is a 10wt% citric acid solution; the preservative is a compound of methylparaben, ethylparaben, and glyceryl caprylate in a mass ratio of 2:1:2, with a total addition amount of 0.1wt% to 1wt%.

7. The stabilization method for a high-concentration amino acid surfactant transparent concentrate according to claim 1, characterized in that: In step two, the stirring speed is 130 r / min and the stirring time is 12 min; in step three, the interval between each addition is 9 min, and the stirring time is 13 min after each addition. The temperature of the first addition is 38℃, the temperature of the second addition is 43℃, and the temperature of the third addition is 49℃.

8. The stabilization method for a high-concentration amino acid surfactant transparent concentrate according to claim 1, characterized in that: In step four, the stirring speed is 90 r / min and the stirring time is 22 min; in step five, the stirring time is 18 min; in step six, the homogenization pressure is 35 MPa, the homogenization is performed 3 times, the maturation temperature is 25℃, and the maturation time is 36 h.

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