Natural capsaicin and a method for preparing the same

Abstract

The application provides a preparation method of natural capsaicin, comprising the following steps: a) mixing oil-soluble oleoresin capsicum with polysorbate dispersant to obtain a mixed solution; b) mixing and dissolving the mixed solution with lye, and then performing dilution treatment to obtain a diluted solution; and c) adjusting the pH value of the diluted solution, and then performing crystallization to obtain capsaicin. The application also provides natural capsaicin. In the application, polysorbate compound is used as a dispersant, mixed with oil-soluble oleoresin capsicum, dissolved with lye, diluted, and then crystallized after adjusting the pH value to obtain natural capsaicin. The natural capsaicin obtained by the method provided by the application mainly comprises capsaicin, dihydrocapsaicin, nordihydrocapsaicin, vanillyl nitrile, capsaicin II and dihydrocapsaicin I, and has the advantages of clear components, high purity and high transfer rate.

Description

Technical Field

[0001] This invention relates to the field of chemical technology, and in particular to a natural capsaicin and its preparation method. Background Technology

[0002] Capsaicin is a natural plant alkaloid extracted from the mature fruit of the chili pepper plant (a member of the Solanaceae family). It consists of various vanillylamide compounds, with three being the most abundant: capsaicin, dihydyocapsaicin, and nordihydrocapsaicin. It possesses analgesic, antioxidant, antipruritic, appetite-stimulating, digestive-improving, antibacterial, insecticidal, and antioxidant properties, and is widely used to treat arthritis, muscle pain, back pain, sports sprains, and postherpetic neuralgia.

[0003] Currently, capsaicin is mostly extracted from capsaicin oleoresin (oil-soluble capsaicin) using acid-base extraction and organic solvent extraction methods. Chinese patent CN104276970B discloses an acid-base method for preparing capsaicin, comprising the following steps: A) Heating a 5% alkaline solution (prepared with caustic soda) to 60-70°C, then adding 50% (by weight) of capsaicin oleoresin and stirring to dissolve; B) Adding 5-10 times the weight of water to the alkaline solution, heating to 40-60°C, and mixing thoroughly to dissolve and disperse the pigment; C) Titrating the solution with hydrochloric acid to a pH of 6-9; D) Allowing to stand and cool for 72-96 hours until complete crystallization; E) Centrifuging and filtering, washing the crystals with water, and drying to obtain the finished capsaicin; F) Adding 4-6 times the weight of salt to the mother liquor, stirring thoroughly, allowing to stand for 10 days, filtering, and emulsifying the filtrate to obtain a water-soluble capsaicin product. However, this method is not ideal for dissolving and dispersing pigments, and it cannot completely remove oily substances from the raw materials. The resulting product contains few types of vanillylamide compounds (components of capsaicin), has unclear composition, low purity, and a low transfer rate. Summary of the Invention

[0004] In view of this, the technical problem to be solved by the present invention is to provide a method for preparing natural capsaicin. The natural capsaicin prepared by the method provided by the present invention has a clear composition, high purity and high transfer rate.

[0005] This invention provides a method for preparing natural capsaicin, comprising the following steps:

[0006] a) Mix oil-soluble capsaicin with a polysorbate dispersant to obtain a mixture;

[0007] b) The mixture is dissolved in an alkaline solution and then diluted to obtain a diluted solution;

[0008] c) After adjusting the pH of the diluted solution, crystallization is carried out to obtain capsaicin.

[0009] This invention uses polysorbate compounds as dispersants, mixes them with oil-soluble capsaicin, dissolves them in alkali, dilutes them, adjusts the pH value, and then recrystallizes them to obtain natural capsaicin. The natural capsaicin obtained by the method provided by this invention mainly consists of capsaicin, dihydrocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, high capsaicin II, and high dihydrocapsaicin I. The components are clearly defined, with high purity and high transfer rate.

[0010] In some specific implementations, the polysorbate dispersant is polysorbate 80. The applicant has found that other nonionic surfactants besides polysorbates cannot improve the purity of the obtained natural capsaicin; however, among polysorbate dispersants, polysorbate 80, compared with other types, yields a more clearly defined natural capsaicin composition and higher purity.

[0011] This application does not impose any special restrictions on the source of the oil-soluble capsaicin; it can be purchased directly from the market and prepared according to the following method:

[0012] Chili peppers are crushed and then extracted using supercritical CO2 at 50–60°C and 15–25 MPa to obtain oil-soluble capsaicin.

[0013] In some specific implementations, the capsaicin content in the oil-soluble capsaicin, i.e., the concentration of the oil-soluble capsaicin, is 20% or more, preferably 30-40%.

[0014] This invention first mixes a dispersant and an oil-soluble capsaicin. In some specific implementations, the weight ratio of the oil-soluble capsaicin to the polysorbate dispersant is 1:0.5–1.5, preferably 1:0.8–1.2. In some specific implementations, the mixing temperature is 50–100°C, preferably 70–80°C, and the mixing time is 5–30 min, preferably 10–20 min. In some specific implementations, the mixing is preferably carried out under stirring conditions.

[0015] After obtaining the mixture, it is dissolved and diluted with an alkaline solution. In some specific implementations, the alkaline solution is selected from one or more of sodium hydroxide aqueous solution and potassium hydroxide aqueous solution. In some specific implementations, the mass concentration of the alkaline solution is 1% to 15%, preferably 5% to 10%. In some specific implementations, the weight ratio of the alkaline solution to the oil-soluble capsaicin is 1 to 5:1, preferably 2 to 3:1. In some specific implementations, the mixing and dissolving temperature is 50 to 100°C, preferably 70 to 80°C, and the mixing and dissolving time is 5 to 30 minutes, preferably 10 to 20 minutes. In some specific implementations, the mixing and dissolving is carried out under stirring conditions.

[0016] In some specific implementations, an alkaline solution is added to dissolve the substance, followed by dilution with water to ensure the oil-soluble capsaicin is fully dissolved and dispersed. In some specific implementations, the mass ratio of water to oil-soluble capsaicin is 20–50:1, preferably 30–40:1.

[0017] After obtaining the diluted solution, the pH value of the diluted solution is adjusted and crystallization is carried out to obtain capsaicin. In some specific implementations, the pH value of the diluted solution is adjusted to 9-10, preferably to 9.1-10. In some specific implementations, an aqueous hydrochloric acid solution is used to adjust the pH value, and the concentration of the aqueous hydrochloric acid solution is 5-15%, preferably 10%.

[0018] In some specific implementations, the crystallization specifically refers to:

[0019] The diluted solution, after pH adjustment, was filtered through a titanium rod and then subjected to both cold crystallization and room temperature crystallization to obtain capsaicin. Specifically, the diluted solution, after pH adjustment, was filtered through a titanium rod to remove water-insoluble impurities, then subjected to cold crystallization followed by room temperature crystallization to obtain natural capsaicin.

[0020] In some specific implementations, after room temperature crystallization, the process also includes: filtration under reduced pressure and washing the resulting crystals.

[0021] The present invention also provides a natural capsaicin, comprising: capsaicin, dihydrocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, high capsaicin II, and high dihydrocapsaicin I.

[0022] This invention uses polysorbate compounds as dispersants, mixes them with oil-soluble capsaicin, dilutes them with an alkaline mixed solvent, adjusts the pH value, and then recrystallizes to obtain natural capsaicin. On the one hand, the method provided by this invention overcomes the shortcomings of acid-base methods, effectively removing oils and pigments, and improving the purity and transfer rate of natural alkaloids. On the other hand, the method provided by this invention avoids the production risks associated with using large amounts of organic solvents. Under equivalent production conditions, product yield is increased by 3-5 times, costs are saved by 50%-65%, and quality is improved by 5%-10%. Most importantly, the natural capsaicin obtained by the method provided by this invention mainly consists of capsaicin, dihydrocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, homocapsaicin II, and homodihydrocapsaicin I, with clearly defined components, high purity, and high transfer rate. Experimental results show that the natural capsaicin obtained by the method provided in this application can achieve a purity of over 99% and a transfer rate of over 40%. Attached Figure Description

[0023] Figure 1 This is the HPLC chromatogram of capsaicin obtained in Example 1 of this application. Detailed Implementation

[0024] The preparation method of natural capsaicin provided by the present invention will be described in detail below with reference to the embodiments.

[0025] Example 1

[0026] (1) Prepare materials: Prepare 35% oil-soluble capsaicin, polysorbate 80, sodium hydroxide and hydrochloric acid according to the process requirements, and set them aside for use;

[0027] (2) Dissolve sodium hydroxide in water to prepare a 5% sodium hydroxide solution, and dissolve hydrochloric acid in water to prepare a 10% hydrochloric acid solution for later use;

[0028] (3) Mix oil-soluble capsaicin and polysorbate 80 at a weight ratio of 1:1.2 at 70-80°C until homogeneous;

[0029] (4) Add 5% sodium hydroxide solution of 2 times the mass of oil-soluble capsaicin to the solution in step (3) and stir and mix evenly at 70-80℃;

[0030] (5) Add the solution obtained in step (4) to 30 times the amount of water and stir to mix evenly;

[0031] (6) Adjust the pH of the solution obtained in step (5) to 9.00 using 10% hydrochloric acid solution;

[0032] (7) After filtering the solution through a titanium rod to remove water-insoluble impurities, it was refrigerated for 48 hours and then crystallized at room temperature for 72 hours.

[0033] (8) Filter the crystallization solution under reduced pressure, collect the filtrate, wash the crystals with purified water, filter to obtain white crystals, and dry to obtain the finished capsaicin product. Transfer rate: 42%; Content: 99%.

[0034] The capsaicin was analyzed by HPLC, and the results are shown in [reference needed]. Figure 1 , Figure 1 The HPLC chromatogram of capsaicin obtained in Example 1 of this application is from... Figure 1 It is known that the capsaicin prepared by the method provided in this application mainly consists of capsaicin, dihydyocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, high capsaicin II, and high dihydrocapsaicin I, with clearly defined components.

[0035] Example 2

[0036] (1) Prepare materials: Prepare 35% oil-soluble capsaicin, polysorbate 80, sodium hydroxide and hydrochloric acid according to the process requirements, and set them aside for use;

[0037] (2) Dissolve sodium hydroxide in water to prepare a 5% sodium hydroxide solution, and dissolve hydrochloric acid in water to prepare a 10% hydrochloric acid solution for later use;

[0038] (3) Mix oil-soluble capsaicin and polysorbate 80 at a weight ratio of 1:1.2 at 70-80°C until homogeneous;

[0039] (4) Add 5% sodium hydroxide solution of 2 times the mass of oil-soluble capsaicin to the solution in step (3) and stir and mix evenly at 70-80℃;

[0040] (5) Add the solution obtained in step (4) to 30 times the amount of water and stir to mix evenly;

[0041] (6) Adjust the pH of the solution obtained in step (5) to 10.00 using 10% hydrochloric acid solution;

[0042] (7) After filtering the solution through a titanium rod to remove water-insoluble impurities, it was refrigerated for 48 hours and then crystallized at room temperature for 72 hours.

[0043] (8) Filter the crystallization solution under reduced pressure, collect the filtrate, wash the crystals with purified water, filter to obtain white crystals, and dry to obtain the finished capsaicin product. Transfer rate: 41%; content: 100%.

[0044] HPLC analysis of the capsaicin revealed that its main components were capsaicin, dihydyocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, capsaicin II, and capsaicin I, with clearly defined components.

[0045] Example 3

[0046] (1) Prepare materials: Prepare 35% oil-soluble capsaicin, polysorbate 80, sodium hydroxide and hydrochloric acid according to the process requirements, and set them aside for use;

[0047] (2) Dissolve sodium hydroxide in water to prepare a 5% sodium hydroxide solution, and dissolve hydrochloric acid in water to prepare a 10% hydrochloric acid solution for later use;

[0048] (3) Mix oil-soluble capsaicin and polysorbate 80 at a weight ratio of 1:0.8 at 70-80°C until homogeneous;

[0049] (4) Add 5% sodium hydroxide solution of 2 times the mass of oil-soluble capsaicin to the solution in step (3) and stir and mix evenly at 70-80℃;

[0050] (5) Add the solution obtained in step (4) to 30 times the amount of water and stir to mix evenly;

[0051] (6) Adjust the pH of the solution obtained in step (5) to 9.00 using 10% hydrochloric acid solution;

[0052] (7) After filtering the solution through a titanium rod to remove water-insoluble impurities, it was refrigerated for 48 hours and then crystallized at room temperature for 72 hours.

[0053] (8) Filter the crystallization solution under reduced pressure, collect the filtrate, wash the crystals with purified water, filter to obtain white crystals, and dry to obtain the finished capsaicin product. Transfer rate: 44%; content: 98%.

[0054] HPLC analysis of the capsaicin revealed that its main components were capsaicin, dihydyocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, capsaicin II, and capsaicin I, with clearly defined components.

[0055] Example 4

[0056] (1) Prepare materials: Prepare 35% oil-soluble capsaicin, polysorbate 80, sodium hydroxide and hydrochloric acid according to the process requirements, and set them aside for use;

[0057] (2) Dissolve sodium hydroxide in water to prepare a 5% sodium hydroxide solution, and dissolve hydrochloric acid in water to prepare a 10% hydrochloric acid solution for later use;

[0058] (3) Mix oil-soluble capsaicin and polysorbate 80 at a weight ratio of 1:0.8 at 70-80°C until homogeneous;

[0059] (4) Add 5% sodium hydroxide solution of 2 times the mass of oil-soluble capsaicin to the solution in step (3) and stir and mix evenly at 70-80℃;

[0060] (5) Add the solution obtained in step (4) to 30 times the amount of water and stir to mix evenly;

[0061] (6) Adjust the pH of the solution obtained in step (5) to 10.00 using 10% hydrochloric acid solution;

[0062] (7) After filtering the solution through a titanium rod to remove water-insoluble impurities, it was refrigerated for 48 hours and then crystallized at room temperature for 72 hours.

[0063] (8) Filter the crystallization solution under reduced pressure, collect the filtrate, wash the crystals with purified water, filter to obtain white crystals, and dry to obtain the finished capsaicin product. Transfer rate: 42%; content: 99%.

[0064] HPLC analysis of the capsaicin revealed that its main components were capsaicin, dihydyocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, capsaicin II, and capsaicin I, with clearly defined components.

[0065] Example 5

[0066] (1) Prepare materials: Prepare 35% oil-soluble capsaicin, polysorbate 80, sodium hydroxide and hydrochloric acid according to the process requirements, and set them aside for use;

[0067] (2) Dissolve sodium hydroxide in water to prepare a 10% sodium hydroxide solution, and dissolve hydrochloric acid in water to prepare a 10% hydrochloric acid solution for later use;

[0068] (3) Mix oil-soluble capsaicin and polysorbate 80 at a weight ratio of 1:1.2 at 70-80°C until homogeneous;

[0069] (4) Add 10% sodium hydroxide solution of 2 times the mass of oil-soluble capsaicin to the solution in step (3) and stir and mix evenly at 70-80℃;

[0070] (5) Add the solution obtained in step (4) to 30 times the amount of water and stir to mix evenly;

[0071] (6) Adjust the pH of the solution obtained in step (5) to 9.00 using 10% hydrochloric acid solution;

[0072] (7) After filtering the solution through a titanium rod to remove water-insoluble impurities, it was refrigerated for 48 hours and then crystallized at room temperature for 72 hours.

[0073] (8) Filter the crystallization solution under reduced pressure, collect the filtrate, wash the crystals with purified water, filter to obtain white crystals, and dry to obtain the finished capsaicin product. Transfer rate: 43%; content: 100%.

[0074] HPLC analysis of the capsaicin revealed that its main components were capsaicin, dihydyocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, capsaicin II, and capsaicin I, with clearly defined components.

[0075] Example 6

[0076] (1) Prepare materials: Prepare 35% oil-soluble capsaicin, polysorbate 80, sodium hydroxide and hydrochloric acid according to the process requirements, and set them aside for use;

[0077] (2) Dissolve sodium hydroxide in water to prepare a 10% sodium hydroxide solution, and dissolve hydrochloric acid in water to prepare a 10% hydrochloric acid solution for later use;

[0078] (3) Mix oil-soluble capsaicin and polysorbate 80 at a weight ratio of 1:1.2 at 70-80°C until homogeneous;

[0079] (4) Add 10% sodium hydroxide solution of 2 times the mass of oil-soluble capsaicin to the solution in step (3) and stir and mix evenly at 70-80℃;

[0080] (5) Add the solution obtained in step (4) to 30 times the amount of water and stir to mix evenly;

[0081] (6) Adjust the pH of the solution obtained in step (5) to 10.00 using 10% hydrochloric acid solution;

[0082] (7) After filtering the solution through a titanium rod to remove water-insoluble impurities, it was refrigerated for 48 hours and then crystallized at room temperature for 72 hours.

[0083] (8) Filter the crystallization solution under reduced pressure, collect the filtrate, wash the crystals with purified water, filter to obtain white crystals, and dry to obtain the finished capsaicin product. Transfer rate: 40%; content: 100%.

[0084] HPLC analysis of the capsaicin revealed that its main components were capsaicin, dihydyocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, capsaicin II, and capsaicin I, with clearly defined components.

[0085] Example 7

[0086] (1) Prepare materials: Prepare 35% oil-soluble capsaicin, polysorbate 80, sodium hydroxide and hydrochloric acid according to the process requirements, and set them aside for use;

[0087] (2) Dissolve sodium hydroxide in water to prepare a 10% sodium hydroxide solution, and dissolve hydrochloric acid in water to prepare a 10% hydrochloric acid solution for later use;

[0088] (3) Mix oil-soluble capsaicin and polysorbate 80 at a weight ratio of 1:0.8 at 70-80°C until homogeneous;

[0089] (4) Add 10% sodium hydroxide solution of 2 times the mass of oil-soluble capsaicin to the solution in step (3) and stir and mix evenly at 70-80℃;

[0090] (5) Add the solution obtained in step (4) to 30 times the amount of water and stir to mix evenly;

[0091] (6) Adjust the pH of the solution obtained in step (5) to 9.00 using 10% hydrochloric acid solution;

[0092] (7) After filtering the solution through a titanium rod to remove water-insoluble impurities, it was refrigerated for 48 hours and then crystallized at room temperature for 72 hours.

[0093] (8) Filter the crystallization solution under reduced pressure, collect the filtrate, wash the crystals with purified water, filter to obtain white crystals, and dry to obtain the finished capsaicin product. Transfer rate: 45%; content: 99%.

[0094] HPLC analysis of the capsaicin revealed that its main components were capsaicin, dihydyocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, capsaicin II, and capsaicin I, with clearly defined components.

[0095] Example 8

[0096] (1) Prepare materials: Prepare 35% oil-soluble capsaicin, polysorbate 80, sodium hydroxide and hydrochloric acid according to the process requirements, and set them aside for use;

[0097] (2) Dissolve sodium hydroxide in water to prepare a 10% sodium hydroxide solution, and dissolve hydrochloric acid in water to prepare a 10% hydrochloric acid solution for later use;

[0098] (3) Mix oil-soluble capsaicin and polysorbate 80 at a weight ratio of 1:0.8 at 70-80°C until homogeneous;

[0099] (4) Add 10% sodium hydroxide solution of 2 times the mass of oil-soluble capsaicin to the solution in step (3) and stir and mix evenly at 70-80℃;

[0100] (5) Add the solution obtained in step (4) to 30 times the amount of water and stir to mix evenly;

[0101] (6) Adjust the pH of the solution obtained in step (5) to 10.00 using 10% hydrochloric acid solution;

[0102] (7) After filtering the solution through a titanium rod to remove water-insoluble impurities, it was refrigerated for 48 hours and then crystallized at room temperature for 72 hours.

[0103] (8) Filter the crystallization solution under reduced pressure, collect the filtrate, wash the crystals with purified water, filter to obtain white crystals, and dry to obtain the finished capsaicin product. Transfer rate: 41%; content: 100%.

[0104] HPLC analysis of the capsaicin revealed that its main components were capsaicin, dihydyocapsaicin, nordihydrocapsaicin, vanillonamide, decanoic vanillonamide, capsaicin II, and capsaicin I, with clearly defined components.

[0105] The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A preparation method of natural capsaicin, comprising the following steps: a) mixing oil-soluble oleoresin with polysorbate dispersant to obtain a mixed solution; the polysorbate dispersant is polysorbate 80; b) mixing and dissolving the mixed solution with lye, and then performing dilution treatment to obtain a diluted solution; c) adjusting the pH value of the diluted solution, and then performing crystallization to obtain capsaicin.

2. The production method according to claim 1, characterized by, In the step c), the crystallization is specifically as follows: After the diluted solution with adjusted pH value is filtered through a titanium rod, cold crystallization and room temperature crystallization are sequentially performed to obtain capsaicin.

3. The preparation method according to claim 1, characterized in that, In the step c), the pH value of the diluted solution is adjusted to 9-10.

4. The method according to any one of claims 1 to 3, characterized in that, The concentration of the oil-soluble oleoresin is more than 20%.

5. The preparation method according to claim 4, characterized in that, The concentration of the oil-soluble oleoresin is 30-40%.

6. The preparation method according to any one of claims 1 to 3, characterized in that, In the step a), the weight ratio of the oil-soluble oleoresin to the polysorbate dispersant is 1:0.5-1.

5. In the step a), the temperature of the mixing is 50-100°C, and the mixing time is 5-30 min.

7. The method of any one of claims 1 to 3, wherein the method further comprises the step of: In the step b), the lye is selected from one or more of the following: sodium hydroxide aqueous solution and potassium hydroxide aqueous solution; ​ The mass concentration of the lye is 1%-15%; The weight ratio of the lye to the oil-soluble capsaicin is 1-3:1; The temperature of the mixing and dissolving is 50-100°C, and the mixing and dissolving time is 5-30 min.

8. The method of any one of claims 1 to 3, wherein the method further comprises the step of: The step c) further comprises: ​ The obtained crystal is subjected to reduced-pressure filtration and washing.

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