(19)
(11) EP 1 916 294 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
15.06.2011 Bulletin 2011/24

(21) Application number: 07020630.5

(22) Date of filing: 22.10.2007
(51) International Patent Classification (IPC): 
C11B 9/02(2006.01)

(54)

Essential oil and aromatic water extraction process from vegetable matrices

Verfahren zur Extraktion von ätherischem Öl und aromatischem Wasser aus Gemüsegrundmassen

Huile essentielle et procédé d'extraction d'eau de matrices végétales


(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR

(30) Priority: 23.10.2006 IT CZ20060028

(43) Date of publication of application:
30.04.2008 Bulletin 2008/18

(73) Proprietor: Universita della Calabria
87036 Arcavacata di Rende (IT)

(72) Inventors:
  • Liguori, Angelo
    87100 Cosenza (IT)
  • Belsito, Emilia Lucia
    87100 Cosenza (IT)
  • Leggio, Antonella
    87040 Montalto Uffugo CS (IT)
  • Chidichimo, Giuseppe
    87036 Rende (IT)

(74) Representative: Perrotta, Aldo 
Corso Umberto 81
88068 Soverto
88068 Soverto (IT)


(56) References cited: : 
WO-A-03/080777
FR-A- 675 658
DE-C- 511 794
FR-A- 2 787 347
   
       
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    Technical field



    [0001] The invention regards an extraction process of natural products from plant material, in the absence of solvent. In particular at the end of this process the obtained products are essential oils and aromatic water, the oils are volatile aromatic compounds that are obtained by distillation of the vapor that is created as a result of the heating of the vegetable matrix, after that the cell structures are demolished and the water in them contained is released.

    State of the art



    [0002] For the extraction of oils and aromatic waters from vegetable matrices in the absence of solvent were used different processes. FR-A-2787347 describes a process that provides for the extraction of oils and aromatic water from plant matrices in the absence of solvent, only taking advantage of the water contained in the vegetable structures and proceeding to the heating under vacuum and the separation of the aqueous phase from the oil. So it is a hydrodistillation process without homogenization of the vegetable matrix, in which by microwave irradiation of plant material the vegetable structures are broken. Moreover in this process heating uniformity is not guaranteed as heating treatment and vacuum conditions are contextual.

    [0003] WO-A-9426853 defines a demolition technique of cell structures of a plant material by irradiation with microwave, aimed at extracting essential oils by hydrodistillation. Also in this case the extraction is performed in the absence of solvent and the obtained water originates from the matrix. Again in this process heating uniformity is not guaranteed as heating treatment and vacuum conditions are contextual.

    [0004] The limits of these processes are as follows:
    • Lack of homogenization of the vegetable matrix;
    • Lack of uniformity of heating temperature because the heating treatment occurs concurrently with the pression reduction.


    [0005] The limitations and disadvantages existing in the state of the art are overcome by the present extraction process of aromatic water and essential oils from plant material, in the absence of solvent, in which the vegetable matrix is placed under vacuum and heated to a temperature higher than the water boiling point, in which the evaporated water comes exclusively from vegetable matrix as a result of the breaking of the cell structures, in which vapors condense by lowering of the temperature, in which after condensation in a collector water and essential oil are recovered, characterized by the fact that the vegetable matrix is homogenized with the addition of a salt soluble in water, that the heating is performed under vacuum with a hot bath.

    [0006] Another characteristic is given by the fact that the salt is an organic salt.

    [0007] Another characteristic is given by the fact that the salt is an inorganic salt.

    [0008] Another characteristic is given by the fact that the vegetable matrix is heated with a hot bath to a temperature 30 degrees higher than the boiling point.

    [0009] Other characteristics and advantages of the invention will appear clear from the following description of some methods of creating the invention, given as non-limiting examples in figure 1.

    Brief description of the figure.



    [0010] 

    Fig. 1: The figure schematically represents a way to realize a system in order to carry out the process object of the invention.


    Description of an embodiment of the invention



    [0011] For the realization of the process object of the present invention, the vegetable matrix is homogenized with an inorganic salt, added to 20%, in order to create on the cell membrane a proper osmotic pressure to the leakage of the water and the consequent demolition of the cell structures and placed in a container 1.

    [0012] The container 1 with the homogenized plant material is placed under vacuum, created by vacuum pump 6 (wide range, centred at 20 mmHg) and the container 1 is dipped in a fluid heating bath 2 previously heated. The temperature of the bath 2 must be at least 30 degrees higher than the water boiling point under the used pressure conditions. The fast heating and vacuum conditions involve the generation of a water vapor current in which the volatile organic components resulting from the demolition of cell structures codistill.

    [0013] The vapors pass through the tube 3 and condense in the collector 4 maintained at low temperature by the cold bath 5.

    [0014] From the collector 4 are recovered:
    1. 1. aromatic water, that is the water contained exclusively in the vegetable matrix, that is made aromatic by the volatile components that codistill with water and that in it are soluble;
    2. 2. essential oil constituted by the volatile components present in the vegetable matrix. This is immiscible in the water.


    [0015] The essential oil is recovered by separation from the aromatic water. The obtained aromatic water is ideal for the preparation of cosmetic products and constitutes (according to the type and the state of the matrix) the 20-80 % in weight of the matrix subjected to the treatment. The aromatic water and the essential oil so obtained can find application in the field of aromatherapy and food productions and aromas.

    [0016] The duration of the separation process is short, only 15-30 minutes per 500 g of material.

    [0017] The process can be applied to flowers, leaves, peels and every kind of vegetable material.

    [0018] The process is performed implementing the following steps:

    1. the organic matrix is homogenized with an organic or inorganic salt, placed under vacuum and heated. The developed vapors are condensed by lowering the temperature.

    1.1 Any organic or inorganic salt, water-soluble, can be used in the process of homogenization. It contributes to demolish the cell structures of the vegetable material and indirectly promotes the heat conduction in the heating step.

    1.2 In experiments carried out without the addition of salt the yields in recovered product are reduced until 50% for aromatic waters and 65% for essential oils.

    1.3 The heating is performed by a fluid bath. The vegetable matrix can be heated also by coils in which a hot fluid flows in and placed in the same matrix.

    1.4 The temperature of the heating fluid can be changed in a single process and/or depending on the material to treat.

    1.5 The products of the process are: 1) essential oil and aromatic water; 2) aromatic water only; 3) essential oil only. The variability of the products depends on the type of matrix, the state of the matrix (fresh or dried) and the period of its collection.

    1.6 The vegetable matrix can be constituted by flowers, leaves, parts of stalk, parts of roots, peels etc.



    [0019] This invention is not limited to the representation given by the figures but can be perfected and modified by men expert in the art without altering the aim of the patent.

    [0020] This invention has numerous advantages and will permit to overcome problems which could not be achieved by heating systems on the market today.


    Claims

    1. Aromatic water and essential oil extraction process from vegetable matrices, in the absence of solvent, in which the vegetable matrix is placed under vacuum and heated to a temperature higher than the water boiling point, in which the water that is obtained from the evaporation comes exclusively from the vegetable matrix as a result of the breaking of the cell structures, in which vapors condense by lowering the temperature, in which after condensation in a collector water and essential oil are recovered, characterized by the fact that the vegetable matrix is homogenized with an homogenizer and with the addition of a salt soluble in water and that the heating is performed under vacuum with a hot bath.
     
    2. Aromatic water and essential oil extraction process from vegetable matrices according to claim 1, characterized by the facet that the salt is an organic salt.
     
    3. Aromatic water and essential oil extraction process from vegetable matrices according to claim 1, characterized by the fact that the salt is an inorganic salt.
     
    4. Aromatic water and essential oil extraction process from vegetable matrices according to claim 1 or 2, characterized by the fact that the vegetable matrix is heated with a hot bath to a temperature 30 degrees higher than the boiling point of water measured at the respective vacuum.
     


    Ansprüche

    1. Extraktionsprozess für aromatisches Wasser und ätherische Öle aus pflanzlichen Grundmassen ohne Lösungsmittel, in dem die pflanzliche Grundmasse einem Vakuum unterworfen und bis auf eine Temperatur über dem Wassersiedepunkt erhitzt wird, wobei das von der Verdampfung gewonnene Wasser aufgrund des Zerfalls der Zellenstrukturen ausschließlich aus der pflanzlichen Grundmasse stammt, die Dämpfe sich durch Temperaturabsenkung niederschlagen und nach ihrem Niederschlag in einem Sammelgefäß daraus Wasser und ätherische Öle rückgewonnen werden, dadurch gekennzeichnet dass die pflanzliche Grundmasse mit einem Homogenisator unter Zusatz eines wasserlöslichen Salzes homogenisiert und die Erhitzung unter Vakuum in einem heißen Bad durchgeführt wird.
     
    2. Extraktionsprozess für aromatisches Wasser und ätherische Öle aus pflanzlichen Grundmassen gemäß Anspruch 1, dadurch gekennzeichnet, dass das Salz aus einem organischen Salz besteht.
     
    3. Extraktionsprozess für aromatisches Wasser und ätherische Öle aus pflanzlichen Grundmassen gemäß Anspruch 1, dadurch gekennzeichnet, dass das Salz aus einem unorganischen Salz besteht.
     
    4. Extraktionsprozess für aromatisches Wasser und ätherische Öle aus pflanzlichen Grundmassen gemäß Anspruch 1 oder 2, dadurch gekennzeichnet, dass die organische Grundmasse in einem heißen Bad bis zu einer Temperatur 30 Grad über der im jeweiligen Vakuum gemessenen Wasser-Siedetemperatur erhitzt wird.
     


    Revendications

    1. Procédé d'extraction d'eau aromatique et d'huile essentielle de matrices végétales en l'absence de solvant, dans lequel la matrice végétale est mise sous vide et chauffée à une température supérieure au point d'ébullition de l'eau, dans lequel l'eau obtenue par évaporation provient exclusivement de la matrice végétale du fait de la rupture des structures cellulaires, dans lequel des vapeurs se condensent par abaissement de la température, dans lequel, après condensation dans un collecteur, l'eau et l'huile essentielle sont récupérées, caractérisé en ce que la matrice végétale est homogénéisée au moyen d'un homogénéisateur et par ajout d'un sel soluble dans l'eau et en ce que le chauffage est effectué sous vide au moyen d'un bain chaud.
     
    2. Procédé d'extraction d'eau aromatique et d'huile essentielle de matrices végétales selon la revendication 1, caractérisé en ce que le sel est un sel organique.
     
    3. Procédé d'extraction d'eau aromatique et d'huile essentielle de matrices végétales selon la revendication 1, caractérisé en ce que le sel est un sel inorganique.
     
    4. Procédé d'extraction d'eau aromatique et d'huile essentielle de matrices végétales selon la revendication 1 ou 2, caractérisé en ce que la matrice végétale est chauffée au moyen d'un bain chaud à une température supérieure de 30 degrés au point d'ébullition de l'eau mesuré sous le vide considéré.
     




    Drawing








    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description