CN109135927B

CN109135927B - Flower essential oil extraction method

Info

Publication number: CN109135927B
Application number: CN201710503908.8A
Authority: CN
Inventors: 不公告发明人
Original assignee: Shanghai Moli Brand Management Co ltd
Current assignee: Shanghai Moli Brand Management Co ltd
Priority date: 2017-06-27
Filing date: 2017-06-27
Publication date: 2022-05-10
Anticipated expiration: 2037-06-27
Also published as: CN109135927A

Abstract

The invention provides a flower essential oil extraction method, which comprises the following steps: picking fresh flowers, putting the fresh flowers into a microwave oven to dry until the weight loss is 50-80%, then storing the flowers, mixing the flowers with water, distilling the mixture, and collecting distillate; extracting with petroleum ether, concentrating the petroleum ether under reduced pressure to obtain oily substance, dissolving with diethyl ether, filtering with microporous filtering membrane, and concentrating the filtrate under reduced pressure to obtain flower essential oil. The method has simple process, high extraction rate of essential oil, and less decomposition by-products.

Description

Flower essential oil extraction method

Technical Field

The invention belongs to the technical field of extraction processes, particularly relates to a flower essential oil extraction method, and particularly relates to a jasmine essential oil extraction method.

Background

Essential oil extracted from natural plant flowers is an important component of natural essence, and plays an important role in daily life and industrial production. Essential oil is mainly used in the industries of food, beverage, medicine and cosmetics, particularly, the demand of the beauty industry for the essential oil is more and more along with the improvement of the living standard of people, and the essence of the most popular hydrotherapy SPA is natural plant essential oil at present.

The earliest applications of perfumes historically began with natural perfumes. The natural perfume includes an original unprocessed animal and plant perfuming part directly used, and also includes a natural perfume which is processed by physical extraction or refining without changing the original components. The 'aroma' emitted by the aromatic flowers in nature gives people an attractive and pleasant feeling.

Since the 90 s of the 20 th century, the global perfumery industry has achieved a high degree of industry monopoly, coupled with the constant weakening of tariff restrictions in world trade, promoting the internationalization trend of international companies. Currently, ten spice essence companies in the world account for over 70 percent of the sales value of the whole spice industry. China starts relatively late, and research on the aspect is less.

Jasmine is a plant of the family Oleaceae, an evergreen shrub, a high-grade perfume plant. The leaf, flower and root of Mirabilis jalapa have medicinal value. Jasmine also has strong fragrance, which many flowers do not have. The main effective component of the jasmine essential oil is volatile oil mainly comprising linalool, cis-3-hexenyl acetate, nerol, cis-3-hexenol and geraniol.

The single-petal jasmine is the most intense one of the jasmine. The single-petal jasmine flower buds open early, the summer flower generally opens at 6-7 nightfall, each hundred flowers are heavy, about 22-25 g of the summer flower, the summer flower is lighter than double-dialectic jasmine, the single-petal jasmine flower is rich in fragrance and fresh and cool in taste, and far exceeds double-petal jasmine flower.

CN104887604A discloses a jasmine essential oil extraction method, which comprises the following steps: (1) adsorption of essential oil: passing the jasmine through a wet air flow at normal temperature, then cooling the wet air with the jasmine essential oil to 0-10 ℃, and removing part of water; removing part of the water condensed water, and adsorbing the essential oil by using an adsorbent; (2) and (3) desorption of essential oil: extracting the activated carbon with supercritical carbon dioxide fluid to obtain flos Jasmini sambac essential oil, adding solvent into the condensed water to recover perfume, and recovering perfume from gas discharged from the induced draft fan.

CN104120037A discloses a method for extracting jasmine essential oil, which comprises the steps of dissolving and freezing jasmine extractum prepared by leaching with petroleum ether or n-pentane with ethanol to remove plant wax impurities, distilling and recovering solvent ethanol, washing with water to remove ethanol to obtain crude jasmine essential oil, further separating the crude jasmine essential oil with supercritical CO2 to remove residual solvent, and obtaining the pure-fragrance jasmine essential oil.

CN103740466A discloses a jasmine essential oil extraction method, which comprises the following steps: (1) adsorption of essential oil: placing fresh jasmine flowers on a flower stand in a closed flower chamber, placing the fresh jasmine flowers in multiple layers, using an induced draft fan to enable wet air to flow through the jasmine flowers at normal temperature, then placing the wet air with the jasmine essential oil in a low-temperature condensation chamber, enabling the temperature of the wet air with the jasmine essential oil to be reduced to 0-10 ℃, and discharging condensed water; removing part of the moisture from the wet air, and adsorbing the wet air by using an adsorbent; (2) and (3) desorption of essential oil: extracting the adsorbent adsorbing the jasmine essential oil by supercritical carbon dioxide fluid to obtain the jasmine essential oil.

CN106318630A discloses a method for extracting jasmine essential oil, which comprises the following steps: (1) removing impurities from jasmine, drying to obtain jasmine pieces with water content of no more than 10%, and pulverizing to 40 mesh; (2) irradiating jasmine grains by using LED light: specifically, the illumination time is 15-25min, the illumination intensity is 15-20lx, and the color temperature of illumination is 5500-6000K; (3) adding 3 times of anhydrous ethanol, and standing at 20 deg.C for 1h to obtain a mixed solution; (4) placing the mixed solution treated in the step (3) into a microwave extraction instrument, and carrying out microwave treatment for 10min under the condition of 400w of microwave power; (5) then extracting with water vapor, refrigerating the collected crude product in a refrigerator at 5 deg.C for 2h, and finally performing centrifugal operation and oil-water separation.

CN105482895A discloses a method for extracting jasmine petal essential oil, which adopts supercritical carbon dioxide to extract peony essential oil, and comprises the following steps: (1) collecting undamaged branches and leaves without dew and with unopened buds at 9-11 am, selecting a basket for loading the picked branches and leaves, conveying the branches and leaves to a flower warehouse, and spreading the branches and leaves in a single layer; (2) cutting off leaves, and reserving 2-3cm long petioles and buds; (3) keeping the flower storehouse ventilated, spraying fog water, keeping the relative humidity between 80 and 90 percent and the temperature between 32 and 34 ℃, and culturing the buds to be open; (4) drying after the petals are unfolded, and sending the petals into an extraction tank under the extraction conditions that: temperature 34 ℃, pressure 20MPa, separator: the temperature is 35-38 ℃, and the pressure is 16 MPa; separating the essential oil in a separator.

CN1202228A discloses a new method for extracting pure natural jasmine essential oil suitable for large-scale industrial production, which is to blow fresh jasmine placed in layers by humid air at room temperature without any solvent treatment process to bring out the fragrant components emitted by the jasmine, and trap the fragrant components by a special adsorbent until the jasmine smells out, and then extract and recover the essential oil in the adsorbent by supercritical carbon dioxide fluid.

"research on extraction technology of jasmine essential oil" advances duckweed, and duckweed, etc., journal of tropical crops, 2014, 35 (2): 406 and 412, analyzing the fragrance releasing mechanism and fragrance components of jasmine, explaining the principle and advantages and disadvantages of the conventional distillation extraction method, solvent extraction method, adsorption method, supercritical CO2 extraction method and other extraction methods of jasmine essential oil, and providing an advanced technology subcritical fluid extraction method as an environment-friendly and efficient jasmine essential oil extraction method according to the special habit of fragrance releasing of jasmine.

In the above-mentioned documents and other prior arts, jasmine essential oil extraction efficiency is low, and degradation of volatile components easily occurs due to solvent action, heat action, and the like during extraction. There is a need in the art for a method for extracting flower essential oil with high extraction efficiency, simple process, and effective reduction of decomposition of aromatic substances during the extraction process.

Disclosure of Invention

In order to solve the above problems at the same time, the present inventors have conducted extensive studies and extensive experiments to study the fragrant components of flowers, particularly jasmine, and have proposed the following technical solutions so that flower essential oil can be obtained at a high extraction rate.

In one aspect of the invention, a flower essential oil extraction method is provided, which comprises the following steps: (1) picking fresh flowers, putting the fresh flowers into a microwave oven to be dried until the weight loss is 50-80%, and then storing the flowers in a refrigerator at the temperature of-5-10 ℃; (2) cutting flowers into pieces, mixing the flowers and water according to the ratio of 1: 3-1: 5, distilling, collecting condensate from a condenser, timing, taking out flower residues every 1-2 hours, simultaneously adding fresh flowers, continuously distilling for 5-10 times, and collecting distillate; (3) adding petroleum ether of 1/3-1/5 into the distillate for extraction, repeating the extraction operation for 2-5 times, and combining the petroleum ether; (4) and concentrating the petroleum ether under reduced pressure to obtain an oily substance, adding ether for dissolving, filtering by using a microporous filtering membrane, and concentrating the filtrate under reduced pressure to obtain the flower essential oil.

Preferably, the storage time in the refrigerator is 10 to 60 days.

Preferably, the flower is a jasmine flower. More preferably, the jasmine is a single-petal jasmine.

In the existing flower essential oil extraction, the essential oil extraction can not be carried out after the flowers are picked, and the flowers are usually stored at normal temperature after being picked. However, in the normal temperature storage process, the aromatic substances in the flowers are easy to change into non-aromatic substances under the condition that the flowers are rich in moisture, and the aromatic substances can be slowly changed into the non-aromatic substances. Therefore, the invention selects to use a microwave oven to dry the mixture until the weight loss is 50-80%, and the preferred weight loss is 70%. The microwave heating is different from the traditional heating mode, does not need a heat conduction process, and can enable the heated material to be a heating body, so that even the material with poor heat conduction can reach the heating temperature in a very short time. For flower heating, water molecules are polarized in a microwave electromagnetic field, have dipole characteristics, change polarity directions continuously along with the frequency of the electromagnetic field, vibrate at high speed to generate friction heat, so that the flowers are heated from the inner deep layer, and the temperatures of the various parts are consistent, the characteristic of microwave heating can enable the flowers to be heated rapidly to reach the critical point temperature of inactivating enzymes in the flowers, migration of water in the flower structure is accelerated, loss of essential oil is minimized, and the essential oil cannot be discolored due to heating. The flowers after rapid dehydration are stored at low temperature, and can be stored for a long time, the essential oil is hardly reduced or deteriorated, and the storage period can be as long as 1 year or even longer. If the microwave rapid dehydration is not performed and the low-temperature storage is directly performed, about 40% of essential oil is lost after 1 year.

Preferably, the single-petal jasmine is a flower half-opened single-petal jasmine.

For the purposes of the present invention, in step (2), the water is water containing NaCl. Preferably, the concentration of NaCl is between 5 and 20% by weight.

Further preferably, the water further comprises 0.1-0.5 wt% of an extraction stabilizer (or a distillation stabilizer). The temperature of the distillation extraction may cause partial decomposition of the essential oil. The distillation according to the invention is preferably steam distillation. The research shows that the steam distillation operation is the simplest among various distillation modes, the distillation temperature of the essential oil can be reduced, and the decomposition or deterioration can be prevented. However, steam distillation also has the disadvantage that it causes thermal decomposition of heat-sensitive compounds in the essential oil and hydrolysis of readily hydrolysable components due to the higher operating temperature. Based on the problems, the current measures are directed to improving distillation equipment, such as pressurized series distillation, continuous distillation, double distillation column distillation, and worm-gear type rapid steam distillation. These approaches are costly and require a large investment. Therefore, the stabilizer is added in the distillation process, so that the thermal decomposition of the essential oil can be reduced to a certain extent. The stabilizer is preferably an imidazoline stabilizer. More preferably, the extraction stabilizer is an imidazoline compound represented by the following formula (I):

when added, the compounds associate with some essential oil components during distillation, thereby reducing thermal degradation, and disassociate upon extraction with organic solvents.

Preliminary studies have shown that the addition of the compound of formula (I) can reduce the thermal decomposition of the essential oil by more than 30%. In particular, the decomposition of linalool can be reduced, as is clear from the infrared spectrum of fig. 1 of the present invention.

In another aspect of the present invention, there is also provided an essential oil of jasmine obtained according to the aforementioned method. Preferably, the content of free alcohol in the jasmine essential oil is 30-70 wt%. Preferably, the linalool content in the jasmine essential oil is greater than 4.0 wt%.

Drawings

FIG. 1 is a graph of an infrared spectrum of jasmine essential oil obtained by a method according to example 2 of the present invention;

FIG. 2 is an infrared spectrum of jasmine essential oil obtained according to the method of comparative example 2 of the present invention.

Detailed description of the preferred embodiments

The present invention will be described in further detail below with reference to the following examples and comparative examples, but the embodiments of the present invention are not limited thereto.

Example 1

Selecting fresh mirabilis jalapa (obtained from Jining Bailixin grass industry Co., Ltd.), putting into a microwave oven for drying until weight loss is 75%, then storing in a refrigerator at-10 ℃ for 30 days, cutting the flowers into pieces, mixing the flowers and water according to the ratio of 1: 4, then distilling, collecting condensate from a condenser, timing, taking out flower residues every 1 hour, simultaneously putting fresh flowers again, continuously distilling for 6 times, and collecting distillate; adding 1/5 petroleum ether into the distillate for extraction, repeating the extraction operation for 3 times, and combining the petroleum ether; concentrating the petroleum ether under reduced pressure to obtain oily substance, dissolving with diethyl ether, filtering with microporous filtering membrane, concentrating the filtrate under reduced pressure to obtain flos Jasmini sambac essential oil, measuring its infrared spectrum curve, and measuring linalool content with GC-MC, wherein linalool content is 4.6 wt.%.

Example 2

Selecting fresh mirabilis jalapa (obtained from Jinningbaixin grass industry Co., Ltd.), putting the fresh mirabilis jalapa into a microwave oven for drying until the weight loss is 75%, then storing the flowers in a refrigerator at the storage temperature of-10 ℃ for 30 days, cutting the flowers into pieces, mixing the flowers and water according to the ratio of 1: 4, wherein the water is an extraction stabilizer (obtained from Bailingwei reagent company) containing 10 wt% of NaCl and 0.2 wt% of the formula (I), distilling the flowers, collecting condensate from a condenser, timing, taking out flower residues every 1 hour, simultaneously putting the flowers again, continuously distilling the flowers for 6 times, and collecting distillate; adding 1/5 petroleum ether into the distillate for extraction, repeating the extraction operation for 3 times, and combining the petroleum ether; concentrating the petroleum ether under reduced pressure to obtain oily substance, dissolving with diethyl ether, filtering with microporous filtering membrane, concentrating the filtrate under reduced pressure to obtain flos Jasmini sambac essential oil, measuring its infrared spectrum curve (see figure 1), and measuring linalool content with GC-MC, wherein linalool content is 5.3 wt.%.

Comparative example 1

This comparative example differs from example 1 only in that the microwave weight loss treatment was not carried out on fresh mirabilis jalapa, while the linalool content was determined by GC-MC as 2.3 wt.%.

Comparative example 2

This comparative example differs from example 2 only in that the extraction stabilizer represented by formula (I) was not added to the water used for extractive distillation, and the infrared spectrum curve of the obtained jasmine essential oil was measured (see fig. 2), while the linalool content was measured by GC-MC, and the linalool content was 2.9 wt.%.

It is clear from the above examples and comparative examples that when the extraction method of the present invention is used, the content of linalool representative of the aromatic substance is significantly higher, indicating that it is more stable during the extraction process, which is mainly benefited by the rapid dehydration by microwaves to improve the storage stability and extraction stability, and the addition of the extraction stabilizer further improves the stability. When the extraction stabilizer represented by the formula (I) is not added, it can be seen from FIG. 2 that the concentration of the extraction stabilizer is 3000cm^-1A distinct absorption peak was observed, which is a peak produced by decomposition of aromatic substances, particularly linalool, by MS analysis.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims. All citations referred to herein are incorporated herein by reference to the extent that no inconsistency is made.

Claims

1. A flower essential oil extraction method comprises the following steps:

(1) picking fresh flowers, putting the fresh flowers into a microwave oven to be dried until the weight loss is 50-80%, and then storing the fresh flowers in a refrigerator at the temperature of-5-10 ℃, wherein the fresh flowers are jasmine flowers;

(2) cutting flowers into pieces, mixing the flowers and water according to the ratio of 1: 3-1: 5, distilling, collecting condensate from a condenser, timing, taking out flower residues every 1-2 hours, simultaneously adding fresh flowers, continuously distilling for 5-10 times, and collecting distillate; the water is NaCl-containing water, the concentration of NaCl is 10 wt%, and the water also contains 0.1-0.5 wt% of an extraction stabilizer, wherein the extraction stabilizer is an imidazoline stabilizer, and the structure of the imidazoline stabilizer is shown as the following formula (I):

(3) adding petroleum ether of 1/3-1/5 into the distillate for extraction, repeating the extraction operation for 2-5 times, and combining the petroleum ether;

(4) and concentrating the petroleum ether under reduced pressure to obtain an oily substance, adding ether for dissolving, filtering by using a microporous filtering membrane, and concentrating the filtrate under reduced pressure to obtain the flower essential oil.

2. The method of claim 1, wherein the jasmine is a single-petal jasmine.

3. The method of claim 2, wherein the single-petal jasmine is a fresh flower half-opened single-petal jasmine.

4. An essential oil of jasmine obtained according to the method of any one of the preceding claims.

5. The jasmine essential oil according to claim 4, wherein the free alcohol content is 30-70 wt%.

6. The jasmine essential oil of claim 5, wherein the linalool content is greater than 4.0% by weight.