FR2787347A1 - Preparation of essential oil emulsion useful in cosmetic, dermatological or food compositions, from plant material, comprises cooling and stirring vapor obtained by microwave irradiation under reduced pressure - Google Patents

Abstract

Preparation of an emulsion based on aromatic vegetable material involves placing the vegetable material in a heated chamber in the absence of solvents, irradiating with microwaves while applying reduced pressure, cooling the vapor containing the essential oils to give a 2-phase solution and stirring to form an emulsion. Preparation of an emulsion based on aromatic vegetable material comprises: (a) placing the vegetable material in a heated chamber in the absence of solvents; (b) irradiating with microwaves while applying reduced pressure, such that the cellular structures are broken up and the aromatic oils are distilled off by water vapor from the vegetable material; (c) cooling the vapor containing the essential oils to give a 2-phase solution; and (d) stirring to form an emulsion. An Independent claim is also included for the emulsion obtained by above method.

Description

1 PROCESS FOR THE MANUFACTURE OF AN EMULSION BASED ON

  AROMATIC PLANT MATERIAL, EMULSION LIKELY TO BE OBTAINED BY SAID METHOD AND USE OF SAID EMULSION5

  The invention relates to a method for manufacturing an emulsion based on aromatic plant material. It also relates to the emulsion capable of being obtained by said process and its use.10 Essential oils and distilled waters have been used for many years in the cosmetic industry, but also in the industry

  food. These oils and waters are volatile and aromatic products extracted from plants, by distillation or expression for the former, only by distillation for the latter.

  In both cases, the distillation of the plant material is carried out by steam distillation of the volatile principles of the plant. The steam is obtained after boiling a certain volume of water, chosen according to the quantity of plant to be distilled. At the end of the process, a two-phase product consisting of an aqueous phase constituting distilled water topped with a supernatant is obtained.

  oily constituting essential oils. The aqueous phase and the oily phase are then separated, the oily phase corresponding to the essential oils, or the aqueous phase corresponding to the distilled water being used separately in the preparation of cosmetic or food products, for their aromatic character and in particular for the more or weaker than they give off.

  Even if distillation makes it possible to obtain essential oils on one side and distilled waters rich in aromatic products on the other, in any case, a completely natural product is obtained insofar as the water leading to the formation water vapor is "external" water, that is to say water supplied from

outdoor environment.

  In addition, the aqueous phase and the oily phase are used separately,

  so that we do not have a product comprising all the volatile and aromatic components of the base plant.

  In other words, the problem which the invention proposes to solve is multiple, since it aims: * on the one hand, to propose a product which can be used without being limiting in the cosmetic or food industry, comprising volatile and aromatic components of plant origin, which is entirely natural; + on the other hand, to provide a product containing all of the aromatic constituents of the chosen plant; + finally, to propose a simple manufacturing process in a reduced number of steps, which can be implemented from the plant

  aromatic whole or part of said plant.

  To do this, the invention relates to a method of manufacturing an emulsion based on aromatic plant material according to which: a aromatic plant material is placed in a heated enclosure in the absence of any solvent; ò the plant material is then subjected to microwave irradiation, by simultaneously applying inside the heated enclosure a reduced pressure so as to cause the bursting of the cellular structures leading to the hydrodistillation of the aromatic oil by entraining it in the water vapor from the plant material; the water vapor containing the essential oil is then refrigerated in order to obtain a two-phase solution;

  finally, the two-phase solution is agitated in order to obtain an emulsion.

  The process for extracting volatile principles from the plant, by irradiation of the plant material by microwave and without solvent, is well known to those skilled in the art.

  profession and more particularly described in document FR-A-2 705 035.

  Essentially, this process consists in extracting the essential oil entrained in the azeotropic mixture formed with the steam of clean water in the plant material treated in the absence of solvent. Under the combined effect of selective microwave heating and reduced pressure applied sequentially in the extraction enclosure, the water of constitution of the plant suddenly comes to a boil. The contents of the cells are transferred to the outside of the biological tissue and the essential oil is entrained in the azeotropic mixture formed with the water vapor specific to the treated product. Steam containing essential oil

  is then condensed, then cooled before decantation.

  In other words, the invention provides a single-step manufacturing process for an emulsion in which the essential oils and the plant water, which also comprises the water-soluble fraction of the essential oils are

  remixed, thus providing a product comprising all the aromatic essences contained in the basic plant material.

  In addition, this type of extraction process makes it possible to have a natural emulsion insofar as the water constituting the aqueous phase comes from the water of the plant itself. Indeed, and as already said, water results from the evaporation of the water contained in the plant material, which is released after bursting of cellular structures.15

  According to a particular embodiment of the invention, the biphasic solution is mixed with a surfactant.

  Advantageously, the two-phase solution is previously homogenized.

  In practice, the homogenization can be carried out by stirring at low speed of the order of 100 revolutions / minute.

  To obtain a 100% natural emulsion, the surfactant is of origin

natural.

  In practice, the surfactant is a natural emulsifier advantageously chosen from the group comprising in particular sugar derivatives,

  phospholipids, polyglycerol esters and their derivatives, alkyl polyglucosides30 and their derivatives, alone or as a mixture.

  As already said, the invention also relates to the emulsion capable of being obtained by the process.

  The emulsion of the invention is characterized in that it comprises: * as a lipophilic phase, essential oils extracted from an aromatic plant;

  * as a hydrophilic phase, water extracted from the same plant.

  The invention also relates to the use of the emulsion based on aromatic plant material within a cosmetic composition,

  dermopharmaceutical or dietetic.

  The emulsion of the invention can thus be incorporated into cosmetic forms such as creams, ointments, etc.

  It can also be in liquid form used as a dietetic or food drink.

  In another embodiment, the emulsion of the invention comprises a surfactant of natural origin.

  Advantageously, the lipophilic and hydrophilic phases represent

  99.5% to 85% by weight of the emulsion, the complement to 100% consisting of the surfactant.

  The invention and the advantages which result therefrom will emerge more clearly from the following exemplary embodiments.

Example 1

  Preparation of an peppermint emulsion (mentha piperata) As already said, the process of extracting essential oils by

  microwave irradiation is known, and described in particular in document FR-A-2 705 035, as is the equipment for implementing the method.

  In this example, we use Gyma frozen mint with

14.7% dry matter.

  Given the low capacity of the machine used (10 liters), two successive tests are carried out using 1.5 kg of frozen mint.

  The peppermint is placed in a double envelope enclosure, the temperature of the double envelope of which is 60 ° C., so that the temperature of the vegetable material is less than 60 ° C.

  The microwave power applied is 600 watts.

  During extraction, the pressure is lowered to 100 mbar intermittently.

  The total duration of the extraction for each test is approximately 20 minutes.

  In the first test, 557 g of two-phase solution are obtained, while the second test results in 570 g of solution.

  The solution is then homogenized by stirring with a Turbula at a speed of 90 revolutions per minute for 30 minutes.

  The emulsion of the invention is then produced by mixing the biphasic solution obtained with a surfactant of natural origin.

  The mixing is carried out for 30 minutes by stirring at a rate of 90

revolutions per minute at the Turbula.

  The surfactants used are, as desired, sucrose cocoate, decyl glucoside and a mixture of phospholipids (lecithin glycerin and alcohol), also known as Pro lipo duo. 30 In the following table is shown the composition of each of the emulsions produced ( in grams) by varying the proportions of each of the constituents. Biphasic solution 19.8 19.5 19 18 Coconut sugar 0.2 0.5 1 2 Decyl glucoside 0.2 0.5 1 2 Pro lipo duo 0.2 0.5 1 2

  In all cases, an emulsion stable at room temperature is obtained.

Example 2

  Preparation of a lemon balm emulsion

  The procedure is the same as in Example 1, replacing the mint with lemon balm leaves.

  Example 3 Preparation of a Juniper Emulsion

  The procedure is the same as in Example 1, replacing the mint with juniper berries.

Example 4

  Preparation of a grapefruit emulsion The procedure is the same as in Example 1, replacing the

mint with grapefruit (fruit).

  The advantages of the invention appear clearly from the description.

  Thus, the process for preparing the emulsion of the invention makes it possible to obtain a natural product rich in aromatic essences, insofar as within the same composition, it contains distilled water and essential oils,

  distilled water being made up of the plant water itself.

  In addition, the method is simple to implement and requires only one

manufacturing stage.

Claims (8)

  1 / A method of manufacturing an emulsion based on aromatic plant material according to which: a aromatic plant material is placed in a heated enclosure in the absence of any solvent; * the plant material is then subjected to microwave irradiation, by simultaneously applying to the interior of the heated enclosure a reduced pressure so as to cause the bursting of the cellular structures leading to the hydrodistillation of the aromatic oil by entraining it in the water vapor from the plant material; the water vapor containing the essential oil is then refrigerated in order to obtain a two-phase solution;   * finally, the two-phase solution is agitated in order to obtain an emulsion.   2 / A method according to claim 1, characterized in that the biphasic solution is mixed with a surfactant.   3 / A method according to claim 1, characterized in that the solution   biphasic is previously homogenized before mixing with the surfactant.   4 / Method according to one of claims 2 or 3, characterized in that the surfactant is of natural origin.   / Method according to claim 5, characterized in that the surfactant is a natural emulsifier chosen from the group comprising sugar derivatives, phospholipids, polyglycerol esters and their derivatives, alkyl polyglucosides and their derivatives, alone or as mix. 30   6 / An emulsion capable of being obtained according to one of claims 1 to 5.   7 / Emulsion based on aromatic plant material, characterized in that it comprises: as a lipophilic phase, essential oils extracted from an aromatic plant;   5. as a hydrophilic phase, water extracted from the same plant.   8 / emulsion according to claim 7, characterized in that it comprises a surfactant of natural origin.   9 / emulsion according to claims 7 and 8, characterized in that the lipophilic and hydrophilic phases representing from 99.5% to 85% by weight of the emulsion, the   100% complement consisting of the surfactant.   / Use of the emulsion which is the subject of claims 6 to 9 in a   cosmetic, dermopharmaceutical or dietetic composition.