阅读说明：本技术 一种桂花香精液的制备方法及桂花香精的控制释放方法 (Preparation method of osmanthus fragrans essence and controlled release method of osmanthus fragrans essence ) 是由 范武 柴国璧 张启东 毛健 史清照 徐秀娟 胡军 宋瑜冰 刘俊辉 屈展 宗永立 于 2020-12-03 设计创作，主要内容包括：本发明属于香料制备领域,具体涉及一种桂花香精液的制备方法及桂花香精的控制释放方法。该桂花香精液的制备方法包括以下步骤：桂花香精、N-烷基咪唑、水组成的混合液与二氧化碳混合,形成聚集体溶液；所述N-烷基咪唑的烷基碳原子数为6-8。本发明的桂花香精液的制备方法,最终形成的聚集体溶液透明均一、稳定性好,可避免桂花精油在存放和加香过程中受到损失和破坏,增强了桂花精油在加香应用方面的可行性,拓宽了桂花精油的应用范围。(The invention belongs to the field of spice preparation, and particularly relates to a preparation method of osmanthus fragrans essence and a controlled release method of osmanthus fragrans essence. The preparation method of the sweet osmanthus essence comprises the following steps: mixing a mixed solution consisting of osmanthus essence, N-alkyl imidazole and water with carbon dioxide to form an aggregate solution; the number of alkyl carbon atoms of the N-alkyl imidazole is 6-8. The preparation method of the sweet osmanthus essential oil has the advantages that the finally formed aggregate solution is transparent and uniform and has good stability, the loss and the damage of the sweet osmanthus essential oil in the storage and perfuming processes can be avoided, the feasibility of the sweet osmanthus essential oil in the aspect of perfuming application is enhanced, and the application range of the sweet osmanthus essential oil is widened.)

1. The preparation method of the sweet osmanthus fragrant liquid is characterized by comprising the following steps: mixing a mixed solution consisting of osmanthus essence, N-alkyl imidazole and water with carbon dioxide to form an aggregate solution; the number of alkyl carbon atoms of the N-alkyl imidazole is 6-8.

2. The method for preparing osmanthus fragrans fragrant essence according to claim 1, wherein in the mixed solution, every 100ml of water corresponds to 0.05-0.3g of osmanthus fragrans essence and 0.1-0.6g of N-alkyl imidazole.

3. The method for preparing osmanthus fragrans fragrant essence liquid according to claim 1, wherein the step of mixing with carbon dioxide comprises introducing high-concentration carbon dioxide gas into the mixed liquid, wherein the volume content of carbon dioxide in the high-concentration carbon dioxide gas is at least 80%.

4. The method for preparing osmanthus fragrans fragrant essence liquid according to claim 3, wherein the flow rate of introducing high-concentration carbon dioxide gas is 0.05-0.5L/min for 10-60min per 100ml of mixed liquid.

5. The method for preparing osmanthus fragrans fragrant liquid according to claim 1, wherein the mixing with carbon dioxide comprises adding dry ice to the mixed liquid.

6. The method for preparing osmanthus fragrans fragrant liquid according to claim 1, wherein the N-alkyl imidazole is N-hexyl imidazole or N-octyl imidazole.

7. The method for preparing sweet osmanthus fragrans fragrant liquid as claimed in any one of claims 1 to 6, wherein the average particle size of the aggregate solution is 100-250 nm.

8. A controlled release method of osmanthus essence is characterized by comprising the following steps:

1) mixing a mixed solution consisting of osmanthus essence, N-alkyl imidazole and water with carbon dioxide to form an aggregate solution; the number of alkyl carbon atoms of the N-alkyl imidazole is 6-8;

2) introducing carbon dioxide-poor gas into the aggregate solution formed in the step 1), destroying an aggregate solution system, and releasing osmanthus essence; the carbon dioxide-lean gas is free of carbon dioxide or has a carbon dioxide content of not more than 20% by volume.

9. The method for controlling the release of osmanthus essence according to claim 8, wherein in step 2), the flow rate of the carbon dioxide-poor gas is 0.05-0.5L/min for 1-20min per 100ml of the mixed solution.

10. The method for the controlled release of osmanthus fragrans essence according to claim 8 or 9, wherein said carbon dioxide lean gas is one or a combination of two or more of nitrogen, air and argon.

Technical Field

The invention belongs to the field of spice preparation, and particularly relates to a preparation method of osmanthus fragrans essence and a controlled release method of osmanthus fragrans essence.

Background

The osmanthus essential oil is a high-grade natural floral spice and is a unique product in China. The osmanthus essential oil is insoluble in water, has strong volatility and is sensitive to light and heat, and the characteristics cause the osmanthus essential oil to be easily lost and damaged under the conditions of storage and application, thereby greatly limiting the application of the osmanthus essential oil.

Disclosure of Invention

The invention aims to provide a preparation method of sweet osmanthus essential oil, which realizes uniform and stable dispersion of sweet osmanthus essential oil in an aqueous solution system.

The second purpose of the invention is to provide a controlled release method of osmanthus essence.

In order to achieve the purpose, the technical scheme of the preparation method of the sweet osmanthus fragrant liquid is as follows:

a preparation method of sweet osmanthus essence liquid comprises the following steps: mixing a mixed solution consisting of osmanthus essence, N-alkyl imidazole and water with carbon dioxide to form an aggregate solution; the number of alkyl carbon atoms of the N-alkyl imidazole is 6-8.

Continuously introducing CO into system containing flos Osmanthi Fragrantis essence, N-alkyl imidazole and water₂The N-alkyl imidazole in the system is gradually converted into an N-alkyl imidazole bicarbonate form, and the N-alkyl imidazole bicarbonate has both a water-soluble polar end and an oil-soluble nonpolar end, has surface activity and can self-assemble into an aggregate form in aqueous solutionThe water-insoluble osmanthus essential oil is wrapped in a nonpolar environment of an aggregate formed by N-alkyl imidazole bicarbonate to form a stable embedding system.

The preparation method of the sweet osmanthus essential oil has the advantages that the finally formed aggregate solution is transparent and uniform and has good stability, the loss and the damage of the sweet osmanthus essential oil in the storage and perfuming processes can be avoided, the feasibility of the sweet osmanthus essential oil in the aspect of perfuming application is enhanced, and the application range of the sweet osmanthus essential oil is widened.

In order to form stable and efficient mixed liquid, preferably, the dosage of the osmanthus essence is 0.05-0.3g and the dosage of the N-alkyl imidazole is 0.1-0.6g per 100ml of water. When preparing the mixed solution, the osmanthus essence, the N-alkyl imidazole and the water are mixed. The osmanthus essence, the N-alkyl imidazole and the water cannot form a stable and uniform dispersion system under natural conditions. By mixing the mixed solution and carbon dioxide, a transparent and uniform aggregate solution system with good stability can be formed.

The mixing with carbon dioxide can assist stirring to accelerate the formation of a stable aggregate solution system. The amount of carbon dioxide is sufficient to form an aggregate solution system. Generally, mixing of the mixed liquor and carbon dioxide can be achieved by utilizing the following two ways:

the mixing with the carbon dioxide comprises introducing high-concentration carbon dioxide gas into the mixed solution, wherein the volume content of the carbon dioxide in the high-concentration carbon dioxide gas is at least 80%. Preferably, the flow rate of introducing the high-concentration carbon dioxide gas is 0.05-0.5L/min for 10-60min per 100ml of the mixed solution.

The mixing with carbon dioxide comprises adding dry ice to the mixed liquor.

The alkyl chain length of the N-alkyl imidazole has an influence on the embedding effect and stability of the osmanthus essence, the alkyl chain is preferably straight chain, preferably, the N-alkyl imidazole is N-hexyl imidazole, N-heptane imidazole or N-octyl imidazole, more preferably N-hexyl imidazole.

In order to further preferably stabilize the uniformity of the aggregate solution and in consideration of the convenience of system formation, it is preferable that the average particle diameter of the aggregate solution is 100-250 nm.

The technical scheme of the controlled release method of the osmanthus essence comprises the following steps:

a controlled release method of osmanthus essence comprises the following steps:

1) mixing a mixed solution consisting of osmanthus essence, N-alkyl imidazole and water with carbon dioxide to form an aggregate solution; the number of alkyl carbon atoms of the N-alkyl imidazole is 6-8;

2) introducing carbon dioxide-poor gas into the aggregate solution formed in the step 1), destroying an aggregate solution system, and releasing osmanthus essence; the carbon dioxide-lean gas is free of carbon dioxide or has a carbon dioxide content of not more than 20% by volume.

In aqueous systems, N-alkylimidazoles with CO₂The process of forming N-alkyl imidazole bicarbonate is a reversible process, when carbon dioxide-poor gas is introduced into the system, the introduced gas will react with CO₂Compete for CO in the system₂The expulsion occurs, whereby the reaction to form the N-alkyl imidazole bicarbonate proceeds in reverse, the surface active N-alkyl imidazole bicarbonate reverts to the non-surface active N-alkyl imidazole form, the aggregates are destroyed, and the entrapped osmanthus essence is released.

The controlled release method of osmanthus essence of the invention, CO₂Playing the role of controlling a release switch by an embedding system, destroying the original osmanthus essence embedding system by introducing poor carbon dioxide gas, separating the osmanthus essence from the system, and realizing the controllable release of the spice.

In the step 2), the flow rate of the carbon dioxide-poor gas is 0.05-0.5L/min for 1-20min per 100ml of the mixed solution.

From the aspect of convenience of controlled release, it is preferable that the carbon dioxide-lean gas is one or a combination of two or more of nitrogen, air, and argon.

Drawings

FIG. 1 shows a comparative N-hexylimidazole/water system with CO injection₂A post particle size distribution map;

FIG. 2 is a graph showing a distribution of particle sizes of the aggregate solution obtained in step 2) in example 1 of the present invention;

FIG. 3 is a graph showing the analysis of particle size after the structure of the aggregate solution is destroyed in step 3) in example 1 of the present invention.

Detailed Description

The following examples are provided to further illustrate the practice of the invention.

In the following examples, N-hexylimidazoles were prepared by the following method:

a) imidazole and acrylonitrile react for 2 to 5 hours in a solvent at the temperature of between 50 and 60 ℃, and the solvent is removed to obtain beta-cyanoethylimidazole;

b) reacting beta-cyanoethylimidazole and bromohexane in a solvent at 70-90 ℃ for 9-18h, removing the solvent, adding alkali liquor and chloroform, mixing, separating an organic phase, and washing.

In step a), the solvent may be selected from methanol. The molar ratio of imidazole to acrylonitrile is 1: 1-1.5.

In step b), the solvent may be selected from acetonitrile. The molar ratio of bromohexane to imidazole is 1: 1-1.5. The alkali liquor can be NaOH solution with mass fraction of 5-20%.

First, a specific embodiment of the controlled release method of osmanthus essence of the invention

Example 1

The controlled release method of the osmanthus essence comprises the following steps:

1) 6.8g of imidazole and 8.0g of acrylonitrile were added to 25ml of methanol, the mixture was reacted at 60 ℃ for 3 hours, the solvent was distilled off under reduced pressure to obtain β -cyanoethylimidazole, the β -cyanoethylimidazole was dissolved in 30ml of acetonitrile, 18.0g of bromohexane was added, the mixture was reacted at 75 ℃ for 15 hours, the acetonitrile was distilled off under reduced pressure, 50ml of 15 wt% NaOH solution and 30ml of chloroform were added, and the mixture was kept at 25 ℃ for 1 hour. Separating out an organic phase; the organic phase was washed with 30ml of deionized water to neutrality, and the chloroform solvent was removed by distillation under reduced pressure to obtain N-hexylimidazole.

2) Adding 0.1g of flos Osmanthi Fragrantis essential oil and 0.1g N-hexane imidazole into 50ml of water to form a mixed solution, and introducing CO into the mixed solution at a flow rate of 0.25L/min₂Gas is continuously stirred for 30min to obtain stable embeddingAqueous solution of osmanthus essence (transparent and uniform appearance, aggregate solution in nature).

3) Introducing air into the aqueous solution of step 2) at 40 deg.C at a flow rate of 0.20L/min for 5min, destroying the embedding system, changing from clear to transparent to turbid, and releasing flos Osmanthi Fragrantis essence.

Example 2

The controlled release method of the osmanthus essence comprises the following steps:

1) 6.8g of imidazole and 8.0g of acrylonitrile were added to 30ml of methanol, and the mixture was reacted at 50 ℃ for 4 hours, the solvent was distilled off under reduced pressure to obtain β -cyanoethylimidazole, which was dissolved in 25ml of acetonitrile, 22g of bromohexane was added, the reaction was carried out at 90 ℃ for 11 hours, the acetonitrile was distilled off under reduced pressure, 50ml of 15 wt% NaOH solution and 30ml of chloroform were added, and the reaction was maintained at 25 ℃ for 1 hour. Separating out an organic phase; the organic phase was washed with 30ml of deionized water to neutrality, and the chloroform solvent was removed by distillation under reduced pressure to obtain N-hexylimidazole.

2) Adding 0.1g of flos Osmanthi Fragrantis essential oil and 0.1g N-hexane imidazole into 50ml of water to form a mixed solution, and introducing CO into the mixed solution at a rate of 0.10L/min₂Stirring for 1 hr to obtain stable water solution (transparent and uniform appearance, and aggregate solution).

3) Introducing N into the aqueous solution of step 2) at a flow rate of 0.20L/min at 35 ℃₂And (4) ventilating for 1min, destroying the embedding system, changing the embedding system from clear and transparent to turbid, and releasing the osmanthus essence.

Example 3

The controlled release method of the osmanthus essence comprises the following steps:

1) 6.8g of imidazole and 8.0g of acrylonitrile were added to 25ml of a methanol solution, the mixture was reacted at 60 ℃ for 3 hours, the solvent was distilled off under reduced pressure to obtain β -cyanoethylimidazole, the β -cyanoethylimidazole was dissolved in 30ml of acetonitrile, 22.1g of bromohexane was added, the mixture was reacted at 80 ℃ for 15 hours, the acetonitrile was distilled off under reduced pressure, 50ml of a 15 wt% NaOH solution and 30ml of chloroform were added, and the mixture was held at 25 ℃ for 1 hour. Separating out an organic phase; the organic phase was washed with 30ml of deionized water to neutrality, and the chloroform solvent was removed by distillation under reduced pressure to obtain N-hexylimidazole.

2) Adding 0.15g of flos Osmanthi Fragrantis essential oil and 0.15g of 0.15g N-hexane imidazole into 50ml of water to form a mixed solution, and introducing CO into the mixed solution at a rate of 0.25L/min₂And (4) continuously stirring for 50min to obtain the aqueous solution (transparent and uniform in appearance and aggregate solution) for stably embedding the osmanthus essence.

3) Introducing Ar gas into the aqueous solution obtained in the step 2) at the flow rate of 0.20L/min for 10min at the temperature of 50 ℃, destroying an embedding system, changing the embedding system from a clear and transparent state to a turbid state, and releasing the osmanthus essence.

Example 4

The controlled release method of the osmanthus essence comprises the following steps:

1) 6.8g of imidazole and 8.0g of acrylonitrile were added to 30ml of methanol, and the mixture was reacted at 50 ℃ for 4 hours, the solvent was distilled off under reduced pressure to obtain β -cyanoethylimidazole, which was dissolved in 25ml of acetonitrile, 24g of bromooctane was added, the mixture was reacted at 90 ℃ for 13 hours, the acetonitrile was distilled off under reduced pressure, 50ml of a 15 wt% NaOH solution and 30ml of chloroform were added, and the mixture was kept at 25 ℃ for 1 hour. Separating out an organic phase; the organic phase was washed with 30ml of deionized water to neutrality, and the chloroform solvent was removed by distillation under reduced pressure to obtain N-octyl imidazole.

2) Adding 0.1g of flos Osmanthi Fragrantis essential oil and 0.2g N-octyl imidazole into 50ml of water to form a mixed solution, and introducing CO into the mixed solution at a rate of 0.25L/min₂Stirring for 1 hr to obtain stable water solution (transparent and uniform appearance, and aggregate solution).

3) Introducing N into the aqueous solution of step 2) at 40 ℃ at a flow rate of 0.30L/min₂And (4) ventilating for 6min, destroying the embedding system, changing the embedding system from clear and transparent to turbid, and releasing the osmanthus essence.

Example 5

The controlled release method of the osmanthus essence comprises the following steps:

1) 6.8g of imidazole and 8.0g of acrylonitrile were added to 25ml of a methanol solution, the mixture was reacted at 60 ℃ for 3 hours, the solvent was distilled off under reduced pressure to obtain β -cyanoethylimidazole, the β -cyanoethylimidazole was dissolved in 30ml of acetonitrile, 22.1g of bromohexane was added, the mixture was reacted at 80 ℃ for 15 hours, the acetonitrile was distilled off under reduced pressure, 50ml of a 15 wt% NaOH solution and 30ml of chloroform were added, and the mixture was held at 25 ℃ for 1 hour. Separating out an organic phase; the organic phase was washed with 30ml of deionized water to neutrality, and the chloroform solvent was removed by distillation under reduced pressure to obtain N-hexylimidazole.

2) Adding 0.15g of flos Osmanthi Fragrantis essential oil and 0.3g N-hexane imidazole into 50ml of water to form a mixed solution, and introducing CO into the mixed solution at a rate of 0.3L/min₂And (4) performing gas treatment for 40min to obtain the aqueous solution (transparent and uniform in appearance and aggregate solution in property) for stably embedding the osmanthus essence.

3) Introducing Ar gas into the aqueous solution obtained in the step 2) at the flow rate of 0.25L/min for 20min at room temperature, destroying the embedding system, changing from clear and transparent state to turbid state, and releasing osmanthus essence.

In other embodiments of the method for controlling the release of osmanthus essence of the present invention, dry ice may be optionally added in step 2), and the amount of dry ice added may be sufficient to obtain a stable aggregate solution. The flow rate and time of the gas introduced in the step 2) and the step 3) can be adjusted within the preferable range of the invention, and the experimental effect equivalent to that of the embodiment can be obtained.

Second, the specific embodiment of the preparation method of sweet osmanthus fragrant liquid of the invention

Example 6

The preparation method of the sweet osmanthus fragrans fragrant liquid corresponds to the aqueous solution obtained in the step 2) in the embodiment 1.

Example 7

The preparation method of the sweet osmanthus fragrans fragrant liquid corresponds to the aqueous solution obtained in the step 2) in the embodiment 2.

Example 8

The preparation method of the sweet osmanthus fragrans fragrant liquid corresponds to the aqueous solution obtained in the step 2) in the embodiment 3.

Example 9

The preparation method of the sweet osmanthus fragrans fragrant liquid corresponds to the aqueous solution obtained in the step 2) in the embodiment 4.

Example 10

The preparation method of the sweet osmanthus fragrans fragrant liquid corresponds to the aqueous solution obtained in the step 2) in the embodiment 5.

Third, Experimental example

Experimental example 1

This experimental example was conducted to analyze the particle size of the solution system of example 1.

For comparison, in step 2) of example 1, the solution system in which the osmanthus fragrans essential oil is not added and the ratio of N-hexylimidazole and water is the same as that of example 1 was used, and the result of particle size analysis is shown in fig. 1, where the average particle size is 127.3 nm.

The aggregate solution obtained in step 2) of example 1 was subjected to particle size analysis, and the results are shown in FIG. 2. The results showed that the average particle size was 198.9nm, forming a stable aggregate solution.

And 3) introducing air to destroy the embedding system, wherein the particle size analysis result of the solution system is shown in figure 3, the aggregate size is obviously increased, the average particle size is 336.7nm, and the stability is reduced. The appearance of the system changes from clear to transparent to turbid.

Experimental example 2

In the experimental example, the concentration of methoxyphenylethanol (the main component of the osmanthus essential oil) in the solution system is quantitatively tested by GC-MS. During sampling, samples are taken from the middle of the solution system (after the embedded system is damaged, part of osmanthus essence can be layered, the sampling is carried out aiming at the water phase, and the evaluation result shows that the concentration of the methoxyphenethyl alcohol stably existing in the water phase is high). Sampling 1ml, adding 5ml of acetone solution with an internal standard (the internal standard is threo propionate and vanillyl propionate; the concentration is 1.0 mu g/ml), drying the solution by using anhydrous sodium sulfate, filtering, diluting by 40 times by using the internal standard solution for GC-MS quantitative analysis, wherein the GC-MS conditions are as follows: a chromatographic column: DB-WAXetr (60 m.times.0.25 mm.times.0.25 μm); carrier gas: he; column flow rate: 1 mL/min; sample inlet temperature: 250 ℃; temperature programming: 50 deg.C (0min),3 deg.C/min → 250 deg.C (5 min); a non-shunting mode; GC/MS transmission line temperature: 250 ℃, EI ion source temperature: 230 ℃, quadrupole temperature: 150 ℃; EI ionization energy: 70 eV; scanning mode: an ion scan (152, 121, 91; 178, 122, 105) is selected.

In example 1, the concentration of p-methoxyphenethanol in the aggregate solution was 0.566 mg/mL. After disruption of the aggregate solution, the concentration of p-methoxyphenethanol was 0.087 mg/mL.

In example 2, the concentration of p-methoxyphenethanol in the aggregate solution was 0.482 mg/mL. After breaking the aggregate solution, the concentration of p-methoxyphenethanol was 0.013 mg/mL.

In example 3, the concentration of p-methoxyphenethanol in the aggregate solution was 0.700 mg/mL. After the aggregate solution was disrupted, the concentration of p-methoxyphenethanol was 0.014 mg/mL.

In example 4, the concentration of p-methoxyphenethanol in the aggregate solution was 0.348 mg/mL. After breaking the aggregate solution, the concentration of p-methoxyphenethanol was 0.011 mg/mL.

In example 5, the concentration of p-methoxyphenethanol in the aggregate solution was 0.812 mg/mL. After disruption of the aggregate solution, the concentration of p-methoxyphenethanol was 0.107 mg/mL.

Experimental example 3

This example tests the stability of the aqueous solution obtained in step 2) of example 3. The comparative example is an aqueous solution of osmanthus essence with the same initial concentration of osmanthus essence, and the aqueous solution is prepared by stirring and mixing the osmanthus essence and water.

The aqueous solution obtained in step 2) of example 3 was left at room temperature, and samples were taken after 1 day, 2 days, 3 days, 5 days, 10 days, and 30 days, respectively, and the concentration of p-methoxyphenethanol in the solution was measured by the method of example 2), and the measurement results are shown in table 1.

TABLE 1 content of p-methoxyphenylethanol in embedding solution of Osmanthus fragrans fragrance

As can be seen from table 1, compared with the system without surfactant embedding, the content of the main component p-methoxyphenethyl alcohol in the osmanthus essence in the system is not obviously reduced in the process of placing at room temperature, which indicates that the embedded osmanthus essence has higher stability.