[0001] The present invention is concerned with a process for extraction of plant material.
[0002] Many plants contain odoriferous agents which are highly desirable for the production
of flavoursome products, for example in the field of parfums or cosmetics. The odoriferous
agents can be present in blossoms, leaves, bark, roots and other tissue of a plant.
Some plants contain precursor compounds that can develop into valuable compounds.
[0003] For example, the plants of the
Iridaceae family have valuable compounds in the rhizomes that can develop into scented compounds
named irones. Orris butter or iris butter is such a very valuable product which is
used in the flavour and fragrance industry. Methods for isolating orris butter are
known, usually orris butter is isolated from rhizomes of an iris species. Rhizomes
of iris can be harvested after a cultivation period of 2 to 4 years. The rhizomes
then have to be stored for long time, such as about 3 to 5 years for maturation. Shortly
after harvest the rhizomes contain only precursor compounds of the materials which
are useful in the flavour industry, it is assumed that the scenting compounds are
built during maturation by oxidation. When the rhizomes are ready to be worked up,
they are ground to powder and are extracted either by steam or by solvent extraction.
[0004] Other plants contain odoriferous material in the leaves, blossoms, bark, roots etc..
It is a challenge to isolate odoriferous compounds from plant substrate, it requires
specific conditions as the odoriferous compounds often are very sensitive to temperature,
pressure and other harsh conditions.
[0005] Steam distillation can be used for extracting essential oil from plants. However,
the problem when using steam distillation for extracting essential oils from plants
is the long duration of pre-soaking and distillation, low yield and high cost. Steam
distillation requires the use of higher temperature, which on the one hand can be
detrimental to the sensitive odoriferous agents and on the other hand requires more
energy than methods carried out at room temperature or slightly above. Moreover, no
specificity or selective extraction is possible and hydrophilic substances cannot
be extracted.
[0006] Essential oils or other flavourants can also be extracted using organic solvents
like methanol, toluene, hexane. However, it is necessary to remove any solvent from
the extract as most solvents are undesired or even harmful. Moreover, solvent extraction
is laborious and the resulting extract is quite different from traditional orris butter,
as undesired compounds are extracted as well.
WO 98/49139 relates to a process for the preparation of irones, comprising treating iris rhizomes,
any iris plant tissue containing precursors of irones with an aqueous solution of
a nitrite, and recovering the irones formed.
[0007] Making use of organic solvents can preclude the use of an odoriferous extract in
products that are in contact with human skin, such as in cosmetic products or in food.
Therefore, it is desirable to provide a method for obtaining an odoriferous extract
from plants with no or hardly any "foreign" or undesirable ingredient, a method that
allows extraction of the odoriferous agents under mild conditions and with reasonable
yield and at the same time results in a product, like orris butter, in a quality and
a quantity which is at least equal to products obtained with known processes, or which
results in products of superior quality and/or a higher yield of the desirable components.
[0008] The flavour of orris butter is composed of three main compounds and many compounds
which are present in very minor amounts. The main flavour contributing compounds are
α-, β- and γ-irone.
[0009] The rhizomes comprise about 30% myristic acid or myristic acid ester, sugars and
starch, and only about 0.1 to 0.2% of the valuable flavourants. About 10 to 20% of
the essentials oils are irones, the remaining part being a multiplicity of different
flavoursome or odoriferous compounds.
[0010] The known methods for obtaining orris butter require long and cumbersome proceedings.
For obtaining the essential oils by using steam distillation, the ground rhizomes
have first to be soaked for several hours. The steam distillation then has to be carried
out for more than a day, for example for three days.
[0011] It was the object of the present invention to provide a process for obtaining odoriferous
compounds from plant substrates, such as iris rhizomes, rose or jasmine blossoms,
in an efficient, environmentally friendly, process using mild conditions and to obtain
scented products in a high quantity and quality without using detrimental harmful
conditions, and/or undesirable flammable or combustible solvents.
[0012] This object is achieved by using a process for isolation of odoriferous compounds
as defined in the claims.
[0013] It has been found that by using soap components odoriferous compounds can be isolated
in short time, in high yield and in excellent quality. Surprisingly it is possible
to extract odoriferous agents from a plant substrate in shorter time and at lower
temperature than with the methods known from the prior art, for example at room temperature
or slightly increased temperature and within very short time, such as about 30 to
60 minutes or even less. One explanation for this could be that by using the soap
extracting solution of the present invention the cells in the plant parts are destroyed
or broken up and result in fast release of the odoriferous agents. Furthermore, this
would allow easy access for the soap extracting solution to the desirable compounds.
[0014] Even more surprising it was found that with the method of the present invention it
is possible to vary the notes of a flavour mixture in a controlled manner by varying
components of the soap composition used for extraction. Moreover, the method of the
present invention allows to create flavour mixtures or odoriferous compositions using
components that are naturally contained in plants. The method of the present invention
enables to isolate valuable flavour mixtures for the fragrance industry such as orris
butter, perfume of jasmine or roses or other scentful plants in an efficient and environmentally
friendly manner. Orris butter for example which is one of the most valuable base materials
for the fragrance industry, can be obtained in high yield and excellent quality.
Definitions
[0015] In this description the following definitions are used.
[0016] "Plant" or "plant parts" refers to any type of plant that comprises odoriferous compounds.
[0017] The term "plant substrate" comprises any part of a plant that contains odoriferous
compounds such as roots, rhizomes, air roots, bark, wood, leaves, buds, needles, blossoms,
tissue etc.. The plants or plant parts are harvested as it is known to the skilled
person. It is known that there are plant parts that have to be extracted immediately
after harvest, whereas other plants or plant parts need some time for maturation before
the valuable odoriferous compounds can be extracted. In the case of Iridaceae the
valuable flavourants are not or hardly in the plant when it is harvested but develop
over time under known storage conditions. It is assumed that the flavouring compounds
develop by oxidation. Plant substrate shall refer to any plant or plant part that
has at least some odoriferous content and includes plant powder or plant granules.
[0018] "Plant powder" refers to plants or plant parts that have been crushed or comminuted
to a size that is useful for extraction. Methods for crushing sensitive parts are
known in the art. The method has to be such that the valuable odoriferous compounds
which have a low boiling point are not destroyed or impaired.
[0019] Usually the plants or plant parts are prepared before extraction for example by drying
or storing under controlled conditions. The plants are comminuted to a size small
enough to be extracted and usually plant powders or plant granules are used.
[0020] "Odoriferous agent" refers to any material that yields an odour, a scent or an olfactory
sensation and/or can create olfactory stimuli. It can be one compound or a combination
of compounds that creates an olfactory perception. This term shall comprise any compound
that is indicated as flavourant, flavouring agent, fragrancy, parfum, scent, etc.
[0021] "Flavour mixture" is a mixture of odoriferous agents that create an olfactory perception
and/or induce a scent or odour, such as a natural scent.
[0022] "Aqueous soap extracting solution" (also referred to as extracting medium) refers
to a composition for extracting odoriferous agents that comprises an aqueous solvent
or solvent mixture and dissolved therein at least one soap compound. The soap extracting
solution is a thermodynamically stable solution of one or more soap compounds and
optionally one or more hydrotropic additives, wherein soap and, if used, additive
molecules are dispersed homogenously and wherein soap molecules form micelles or micelle-like
structures, which can also be like liquid crystalline phases and/or wherein soap and
additive molecules together act as surfactants.
[0023] "Aqueous solvent" refers to water or a mixture of water with a minor amount of a
water miscible or hydrophilic solvent, in particular pure water. A water miscible
solvent can be added, but only in an amount that does not interfere with the isolation
of the flavour mixture.
[0024] A "soap compound" is a salt of a fatty acid and a monovalent cation. A soap compound
is in particular a salt of a fatty acid and a monovalent cation that in an aqueous
medium forms micelle-like structures.
[0025] The term "fatty acid" as used in this description refers to an alkyl or aryl carboxylic
acid having a linear, branched, or cyclic chain of 4 to 24 carbon atoms, which can
carry functional groups, for example up to five functional groups, like hydroxy groups,
and can be saturated or mono- or poly-unsaturated. Examples are linear or branched
carboxylic acids or dicarboxylic acids having a chain of 4 to 18 carbon atoms, which
can be substituted with functional groups like hydroxy or alkyl or aryl groups. The
term fatty acid shall also comprise fruit acids like hydroxy carboxylic acids or dicarboxylic
acids.
[0026] A "monovalent cation" can be any positively charged metal or group, in particular
any monovalent metal or group that is naturally present in plants. Examples are positively
charged alkali metal ions, like potassium and sodium, or nitrogen containing charged
units like ammonium or cholinium.
[0027] A "hydrotropic additive" is a compound that solubilises less soluble compounds in
aqueous solution and typically is a surfactant-like molecule having a hydrophilic
part and a hydrophobic part. Hydrotropic additives in the method of the present invention
can generally be used, for example to allow extraction of odour components that otherwise
would not be extracted, like polar substance, or can in particular be used together
with those soap compounds that are not completely water-soluble in water at room temperature
or temperatures up to about 40°C to decrease the dissolution temperature. Thus, any
compound that solubilises a soap compound in an aqueous solution as defined above
or together with a soap compound is homogenously dispersed in an aqueous solution
at a temperature of up to 40°C, that is biocompatible and does not interfere with
the odoriferous agents can be used as hydrotropic additive. Examples for a hydrotropic
additive that are "endogenous" for plants are fruit acids and those fruit acids that
are present in a plant and their salts and esters can be used as long as they have
a hydrotropic or co-surfactant activity in the soap extracting medium and/or in combination
with the fatty acids, examples being cinnamic or mandelic acid. A compound such as
C
6-C
12 dicarboxylic acid or a salt or ester thereof, C
6-C
12 hydroxy carboxylic acid or a salt or ester thereof, branched or cyclic C
6-C
18 fatty acid or a salt or ester thereof, or a mixture of two or more of these compounds
can be useful as hydrotropic additive. For some embodiments also short chain acids
like lactic acid can be contemplated.
[0028] "Iris" refers to plants of the family Iridaceae and comprises Iris germanica, Iris
pallida, Iris pallida argentea variegata, Iris pallida aurea variegata, Iris pallida
alba, Iris neglecta, Iris spectabilis, Iris macedonica, or Iris florentina and /or
other varieties of the species Iris barbata and other iris species of various origin.
Preferred species are iris pallida or iris germanica.
[0029] "Iris substrate" refers to any type or part of Iridaceae, that contains odoriferous
agents and can be extracted. Examples are in particular rhizomes, parts of rhizomes,
rhizomes in crushed or powdered form, rhizome extracts from Iridaceae, wastes that
are recovered after industrial extraction of Iridaceae rhizomes, and any other part
of the plants that contain odoriferous agents.
[0030] It has been found that a flavour extract can be obtained from plants or plant parts
by using the following two steps:
- a) contacting a plant substrate with an aqueous soap extraction solution and
- b) isolating a flavour mixture.
[0031] Thus, a process for isolation of at least one odoriferous agent from a plant substrate
is provided which comprises the steps:
- a) contacting a plant substrate with an aqueous soap extraction solution comprising
an aqueous medium and at least one soap compound R-C(=O)O-M+ or +M-O(O=)C-R-C(=O)O-M+, wherein R is saturated or unsaturated linear, branched or cyclic C3 to C17 alkyl or C6 to C18 aryl, wherein R can be substituted with alkyl, aryl, at least one functional group
such as up to 5 hydroxy groups, and wherein M+ is a monovalent cation and
- b) isolating a flavour mixture comprising at least one odoriferous agent from the
soap extract obtained in step a).
[0032] By using this method a very valuable high quality extract can be obtained which comprises
not only the main flavour compounds of a plant but also the many compounds in minor
amounts that contribute to the flavour, in very short time and using "green" substances.
Moreover, it has been found that using the method of the present invention can provide
a flavour composition that comprises polar as well as non-polar compounds in addition
to those hydrophobic compounds that are available by steam distillation. Thereby different
notes of a plant flavour can be created. The method can be adapted to selectively
extract a particular fraction of flavourants, such as polar components, that can be
extracted by using a short chain fatty acid soap (less than 8 carbon atoms in the
chain) in the extraction medium. When extracting
Iridaceae, it is possible to enrich irones, that can be extracted by using longer chain soaps,
for example by using myristate soap in the extraction medium.
[0033] Parameters that can be used to "tailor" the extract are the number and type of fatty
acids soaps, the number and type of additives, pH-value, temperature. The skilled
person can find the best combination of these parameters to isolate a specific flavour
composition.
[0034] Furthermore, it has been found that it is possible with the method of the present
invention not only to extract valuable flavourants from plants and plant parts, but
that it is also possible to extract predetermined fractions of a flavour or aroma.
It was found that using an aqueous soap dispersion comprising at least two different
soap compounds allows to influence the mixture of extractants. The smaller the extracting
soap is the more polar components are in the flavour extract, whereas polar components
can be avoided, if for example components having higher molar mass are used.
[0035] It has been found that by using the aqueous soap extracting solution according to
the present invention short extraction times, high yield and an extract of high quality
can be achieved because of the mild extraction conditions and in addition specificity
can be obtained when desirable and/or necessary. Furthermore, the soap compounds used
according to the present inventions are derived from fatty acids that are naturally
in the plant. Therefore, the method of the present invention avoids to include an
undesired amount of foreign substances or toxically or environmentally detrimental
substances. Mostly or even only naturally occurring compounds are part of the flavour
mixture which contributes to the high quality of the product.
[0036] In one embodiment the soap compounds used are compounds that are based mainly or
only on fatty acids and cations that are naturally occurring within the plant that
is extracted. For example when extracting Iridaceae, a mixture is used which comprises
a soap of myristic acid, i.e. a fatty acid that is predominantly present in
Iridaceae rhizomes.
[0037] The method of the present invention comprises two steps which both are important
for obtaining the valuable flavour extract. The first step is an extraction step wherein
the odoriferous compounds are extracted from the plant substrate, i.e. plants or parts
thereof, by an aqueous soap extracting solution which comprises at least one or two
soap compounds dissolved or dispersed in an aqueous medium, such as water.
[0038] The extraction step is carried out just by contacting the plant substrate with the
aqueous soap extracting solution of the present invention. The duration of the extracting
step depends on the plant substrate used, for example on the type of the plant and
the size of the substrate. Good results are obtained when extraction is carried out
for about 10 to about 60 min, preferably 15 to 40 min. In the case of iris rhizomes
it has been found, that extracting longer than 30 min does not provide more of the
desirable odoriferous agents. In this case, therefore, contacting times of 20 to 35
min are most preferable.
[0039] If plant substrates are used where odoriferous agents are easy available, for example
a fine powder of leaves or blossoms, contact times of only a few minutes, such as
2 to 10 min. or even 3 to 7 min. can be sometimes sufficient to extract the valuable
parts.
[0040] Depending from the type of soap component the extraction can be carried out at room
temperature or even below or at slightly increased temperatures. A useful temperature
range is 15 to 45°C, preferably 20 to 30°C. The temperature for extraction depends
on the solubility of the soap compound in the extracting medium. If the solubility
of a fatty acid soap is not sufficient, a hydrotropic additive can be added to the
solution as described below.
[0041] Soap compounds that are useful for the extraction according to the present invention
are soaps of fatty acids as defined above, i.e. generally fatty acids, such as saturated
or unsaturated linear, branched or cyclic carboxylic acids or dicarboxylic acids wherein
the carboxylic acid can be an alkyl or aryl carboxylic acid. The fatty acid can also
carry functional groups, in particular hydroxy groups. Fatty acids having one hydroxy
group are preferred, up to five hydroxy groups can be present. Furthermore, the chain
of the carboxylic acid can be substituted with alkyl and aryl groups. The counter
ion is a monovalent cation, preferably a cation which is naturally present in the
plant to be extracted. Examples for useful cations are sodium, potassium, ammonium
and cholinium. Any carboxylic acid salt as defined above can be used as soap compound
of the present invention as long as it has soap properties, i.e. is dissolved in an
aqueous medium and forms micelles or micelle-like structures in an aqueous medium.
[0042] The aqueous soap extracting solution of the present invention comprises one or more
soap compounds and can comprise further agents like hydrotropic additives. It is preferred
that the majority of solutes (moles of fatty acid soaps compared to moles of hydrotropic
additives) in the extracting solution are fatty acid soaps. In particular, when a
mixture of one or more fatty acid soaps and hydrotropic additives is used, the hydrotropic
additive should be used in smaller amounts, such that the molar ratio of all hydrotropic
additives to the total amount of fatty acid soaps is smaller than 1:1, in particular
smaller than 1:2. The extracting solution comprises one or more soap compounds at
least in a critical micelle concentration CMC), i.e. in an amount that results in
micelle-like structures, but preferably above CMC, such as at least 0.01 mol/L, or
at least 0.05 mol/L is useful, in particular at least 0.1 mol/L. More than 5 mol/L
does not increase the yield and, therefore is not economical. The extracting solution
can contain any amount of fatty acid soaps that is useful to extract the desirable
compounds. An amount of about 0.1 to about 20 % by weight of fatty acid soap(s), such
as about 1 to about 5 % by weight has been found useful.
[0043] It has been found that by using a short-chain soap it is possible to extract polar
odoriferous substances that cannot be extracted with steam distillation or with long
chain soaps. However, there can be a problem if a combination of a very short-chain
soap, for example a C
4 soap, with of a long-chain soap, for example a C
14 soap, is used as this can result in a hardly compatible mixture that requires higher
temperatures to get dissolved. Surprisingly, it was found that this problem can be
overcome by adding another soap having a chain length between both which provides
for a better solubility of both in water. A ternary mixture of a C
4 soap with of a long-chain soap, for example a C
14 soap, becomes compatible when a small amount of a medium chain soap, for example
a C
6 or C
8 soap, is added.
[0044] It has been surprisingly found that a combination of soaps of differing length can
provide an extracting soap solution that can be used at room temperature or slightly
higher temperatures, such as below 40°C. The reason is that a combination of soaps
of different lengths can have a solubilising effect if they are carefully combined.
A ternary composition of short-chain, medium-chain and long-chain fatty acid soaps
has been found to lower the dissolution temperature and, therefore, is of particular
use.
[0045] Another approach to overcome the incompatibility is to use a hydrotropic additive
as outlined below.
[0046] The extracting medium of the present invention can also contain one or more hydrotropic
additives to improve the solubility of soap components, to improve extracting properties
of the solution or to tailor the extracting properties, for example to extract more
polar compounds. In particular, when a long chain fatty acid soap is used as soap
component and the solubility is not sufficient at room temperature, the addition of
an additive is favorable. The type of hydrotropic additive depends on the soap compound
used in the extracting medium and the temperature desired for extraction. If for example
the main soap component is a long-chain fatty acid which can be solved in the extraction
medium only at a higher temperature, the additive can be used to lower the dissolution
temperature. Hydrotropic additives that are useful in the method of the present invention
are in particular compounds that are based on fatty acids or fatty alcohols, preferably
fatty acids or alcohols that are naturally occurring in the plant to be extracted.
Examples for additives are carboxylic acids, salts and esters thereof for example
mono- and dicarboxylic acids having alkyl and/or aryl groups. Useful are for example
compounds selected from fatty alcohols, C
6-C
12 dicarboxylic acids or esters thereof, C
6-C
12 hydroxycarboxylic acids or esters thereof, branched or cyclic C
6-C
18 fatty acids or esters thereof or mixtures of any of the mentioned compounds. As outlined
before, a (second or further) fatty acid soap used for extraction can also have hydrotropic
properties and can be used for this purpose.
[0047] For some extractions it is useful to combine compounds of different length. In this
case two or more fatty acid soaps of different length, one or more fatty acid soaps
together with one or more hydrotropic additives with differing length or any combination
thereof can be used.
[0048] If an extraction solution is used that comprises mixtures of fatty acid soaps and
hydrotropic additives as extracting components, it is preferred that the molar concentration
of fatty acid soap(s) is higher than the molar concentration of hydrotropic additves,
i.e. that at least 50 % of the extracting components are soap components. Moreover,
the concentration of fatty acid soap(s) has to be high enough to provide for micelle
formation, i.e. the concentration must be higher than CMC.
[0049] The method of the present invention can be adapted as outlined above to specifically
extract fractions of a flavour mixture or to enrich particularly characterizing parts
of a flavour. For this purpose an extraction medium can be specifically adapted. In
one approach only one specific fatty acid soap is used as extracting component, that
can extract a desired part of the odoriferous agents. For example, myristic acid potassium
or sodium soap can be used to extract irones from
Iridaceae plant material. In another approach at least two fatty acid soaps as defined above,
or at least one fatty acid soap and at least one hydrotropic additive are used.
[0050] A hydrotropic additive as used according to the present invention is a soap like
compound that co-operates with the fatty acid and supports the extraction, has a solubilizing
function, and/or provides for the extraction of a specific fraction of the flavour.
In other words by adjusting the type, number and amount of extracting additivies it
is possible to adapt the extraction properties of the soap dispersion.
[0051] The second step of the method of the present invention, i.e. step b) results in the
isolation of the valuable flavour composition or flavour mixture. The flavour mixture
comprises as many of the desired flavourant compounds as possible, i.e. not only those
flavourants that mainly contribute to the specific flavour of a plant, but also many
compounds in minor amounts that are desirable and/or necessary for a "complete" or
desired olfactory perception. The method of the present invention allows also to tailor
the conditions such that only a specific fraction of odoriferous agents is extracted/isolated.
For example, in the case of
Iridaceae it is possible to obtain the irones in high quantity.
[0052] These odoriferous agents are isolated from the soap extract obtained by contacting
a plant substrate with the aqueous extracting solution. Any method that results in
a separation of an oily phase containing at least part of the fatty acid and the majority
of the extracted odoriferous agents can be used. It has been found that three approaches
are particularly useful for isolation: i) separation of an oily phase by change of
pH value and/or decrease of temperature, ii) precipitation of fatty acids by adding
di- or polyvalent cations, or iii) extraction with an organic solvent, such as ether.
[0053] The flavour of a plant is formed by a composition of compounds which are mainly essential
oils, i.e. compounds having a low boiling point and, therefore, evaporate at ambient
conditions or a temperature that is between ambient temperature and body temperature.
The compounds are evaporated and enter the olfactory organ where they create or induce
the olfactory impression. The more compounds contributing to the flavour are present,
the richer the impression is and the more perfect and valuable the mixture is.
[0054] It may be desirable to extract all or essentially all of those compounds that contribute
to a flavour or it may be desirable to selectively extract a predetermined part thereof.
Furthermore, it is important to recover or isolate as many of those desirable compounds
as possible from the extract.
[0055] In one embodiment of the present invention the flavour mixture is isolated by changing
the pH and/or temperature of the extract, thereby breaking the micelles, so that the
hydrophobic compounds can migrate to the fatty phase or oily phase whereas all aqueous
soluble compounds remain in the aqueous phase.
[0056] Without being bound by theory it is assumed that the soap compounds used according
to the present invention wet or coat the flavourant compounds in the plant substrate
and enclose them within micelles. The hydrophobic flavourant compounds, which are
mostly essential oils, i.e. organic compounds that are hydrophobic, are attracted
by the hydrophobic part of the soap, i.e. the fatty acid part or alkyl chain part,
and, therefore, end up in the center of the micelle. The lipophobic part of the soap,
i.e. the acid part or carboxylic group is disposed such that it forms an outer layer
which is in contact with the aqueous solution that is part of the extraction medium.
[0057] Moreover, it was found that the speed of pH change or neutralisation can have an
influence on the yield and composition of the final product. It seems that the slower
the neutralising or pH modifying agent is added the higher is the yield of the valuable
odoriferous agents. One explanation could be that by changing pH of the extract slowly
the odoriferous agents have more time to migrate or adhere to the migrating hydrophobic
agent. Therefore, preferably the pH change is done slowly, such as within a period
of 10 seconds to 120 minutes, or 20 seconds to 60 minutes, such as 30 seconds or 1
minute to 25 or 30 minutes. The best time period for the addition of the pH modifying
agent depends from the components and the temperature used and the optimal time can
be found with routine experiments.
[0058] As soon as the pH value of this medium is changed, i.e. lowered, protons migrate
to the carboxylic group of the fatty acid and protonate it. The neutralized fatty
acid becomes water insoluble and migrates into the oily phase. It is assumed without
being bound by theory that the hydrophobic flavourant compounds still adhere to the
hydrophobic part of the fatty acid and thereby together with the protonated fatty
acids separate as oily phase.
[0059] By changing the pH value the micelles break up and phase separation occurs such that
the extract medium separates in an aqueous phase and an oily phase. All hydrophobic
components migrate to the oily phase, whereas aqueous soluble parts and hydrophilic
compounds migrate to the aqueous phase. The most valuable components of the extract,
i.e. the flavourants which are essential oils migrate together with the fatty acids
into the oily phase and can be separated together with the oily phase. Thereby, a
flavour mixture can be isolated wherein the flavourants are embedded in an oily phase
which is formed primarily by the fatty acids which have been added as soap components
and fatty acids which are native part of the plant substrate.
[0060] By using those soap compounds that are derived from fatty acids that are naturally
in the plant or plant substrate to be extracted, the obtained flavour mixture will
be comprised only of those compounds that are naturally part of the fragrance containing
plant. This results in a particularly harmonic and naturally scenting flavour.
[0061] To enrich odoriferous agents and at least part of the fatty acid soaps in the oily
phase the pH value of the extract that has been obtained by contacting the plant substrate
with an aqueous soap dispersion can be lowered by any acidifying or neutralizing agent
that is environmentally acceptable, does not destroy or impede the flavour mixture,
is not harmful to humans or animals and is commonly available. Examples are acetic
acid, citric acid, hydrochloric acid.. To facilitate separation of fatty acids and
odoriferous agents the temperature of the mixture can be slightly increased after
neutralisation. In another embodiment alkali or alkali earth salts can be added to
adapt the pH value of the extracting solution.
[0062] The extract obtained by the above mentioned step comprises fatty acids and odoriferous
agents, such aus irones. The extract can comprise further desirable or undesirable
components that have been extracted from the plant material, and a residual amount
of water and aqueous or water soluble components. This might destabilize the extract
physically and/or microbially and lead to problems for storage and further use. Furthermore,
it can be desirable to further enrich odoriferous agents, such a irones, in the extract.
[0063] Therefore, at least one further step for further concentration can be carried out.
Although common methods for concentration of hydrophobic agents can be used, this
is an improvement over known methods, as it is not the raw extract with a lot of plant
material and undesired components but a pre-enriched extract which is subjected to
the concentration.
[0064] The following steps can be carried out each independently or in any combination.
- 1) A precipitate/extract obtained after a pH change can be subjected to hydrodestillation.
As there are only minor amounts of plant material the disadvantages that occurred
in the prior art methods do no longer or hardly exist. Therefore, a lower amount and
shorter period are necessary to isolate odoriferous agents.
- 2) It is also possible to subject the extract obtained after pH change or hydrodestillation
to an enfleurage step, as is known in the field of parfums and scents. In this step,
the precipitate/extract can be treated with ethanol to dissolve odoriferous agents.
[0065] The fatty acid will migrate to the ethanol phase and can be recovered. For example,
myristic acid is soluble in ethanol at a temperature slightly above room temperature.
At a temperature slightly above room temperature, such as about 28-35°C more or less
all myristic acid is found dissolved in the ethanol phase.. When cooling this phase,
myristic acid will precipitate and can be separated, for example by using filtering
means, whereas odoriferous agents remain in the ethanol phase. When ethanol is removed,
an enriched preparation of odoriferous agents is obtained. The fatty acid can be recycled
and used in another extraction step.
[0066] The flavor mixture can also be isolated by precipitating fatty acids that are present
in the soap extract by adding di- and/or polyvalent cations. As is known, magnesium,
calcium and other di- or polyvalent salts of fatty acids are insoluble in an aqueous
medium and, therefore, by adding such cations the fatty acid soaps are precipitated
as divalent salts. Such precipitated extract that primarily comprises the fatty acid
salts and the odoriferous agents can be used as such. Furthermore, it is possible
to isolate a flavour mixture from this precipitated extract by contacting the extract
with an organic solvent, such as an ether or alcohol, for example diethyl ether or
ethanol to dissolve the flavoring agents. The obtained slurry can then be filtered
to separate the dissolved flavor mixture. Afterwards the solvent is removed as known
to the skilled person, i.e. for example by evaporation.
[0067] A further option to isolate the flavor mixture from the soap extract is the use of
an organic solvent or an organic solvent mixture to extract all desirable compounds
from the extract. Organic solvents that are useful for this approach are known and
can be those solvents that are used for extraction methods known in the prior art.
A solvent extract obtained by extracting the soap extract of the present invention
differs from a solvent extract, obtained by a method known in the prior art, because
in the soap extract the valuable flavor components have been enriched and undesirable
components are not or hardly present in the soap extract and, thus, cannot be extracted
by the solvent.
[0068] As an example the extraction of an
Iridaceae substrate is described to more clearly show the method of the present invention.
[0069] Rhizomes of an
Iridaceae plant, for example rhizomes of
Iris germanica, Iris pallidae or
Iris florentina_or a mixture thereof is "matured" to allow the irones to build. As soon as the rhizomes
are ripe to be extracted, the rhizomes are crushed to obtain a powder of
Iridaceae rhizome. This powder is then contacted with an aqueous dispersion of an aqueous solvent
wherein at least one soap component is dispersed. The aqueous dispersion is the extraction
medium and comprises at least one, preferably at least two or even three or more soap
components.
[0070] It has been found that a combination of at least three different soaps results in
a very rich flavour mixture with very high quality and excellent olfactory properties.
The soap components can be components that are used in soaps, i.e. metal salts of
fatty acids, wherein the fatty acids can be saturated or unsaturated and preferably
are saturated because saturated fatty acids are more stable and not prone to rancidity,
and can be straight chained or branched or cyclic. It is preferred to use a combination
of fatty acids that are part of the fatty or oily part of the plant substrates to
be extracted. In the case of
Iridaceae, where a myristic acid is the most dominant fatty acid present in the rhizomes, a
myristic acid salt, referred to as M
+C
14-, is used as one component in the extract medium. Furthermore, it has been found that
salts of fatty acids having a low number of carbon atoms are useful for extracting
polar compounds from the plant substrate. Therefore, one component of the extract
medium preferably is a soap component having four carbon atoms (M
+C
4-).
[0071] Furthermore it has been found that some components M
+C
4- and M
+C
14- are not very compatible with each other, i.e. cannot provide an extraction medium
without forming phases, at least when they are used in amounts that are useful to
extract major parts of the flavour mixture. Surprisingly it was found that in this
case when adding a soap component that has a size between the low chain soap component
and the high chain soap component, for example M
+C
8-, this medium chain soap component functions as solubilizer. Therefore, a mixture
of a low chain soap component, high chain soap component and medium soap component
has proven to be very useful as extraction medium. In another embodiment one or more
hydrotropic additives can be used instead of M
+C
4- or M
+C
8-, or in addition. Further soaps can be added to obtain even a broader spectrum of
flavourant compounds out of the plant substrate.
[0072] The flavour mixture obtained by extracting the iris substrate can be isolated from
the soap extract as described above. In one embodiment a solvent or solvent mixture
is used which is immiscible with the aqueous phase, can dissolve the odoriferous agents
and other flavourant components together with the fatty phase. The solvent or solvent
mixture has to be environmentally compatible, may not harm the flavourant compounds
and may not be detrimental to the health. Suitable solvents are ethers and esters
or other solvents that are used for extracting flavourants, such as hexane, tetrahydrofurane
etc.. The mixture extracted from the extract medium which is a composition comprising
a solvent or a solvent mixture together with the oily parts of the extract is then
processed by removing the solvent or solvent mixture. This can be done either by evaporation
or by any other means known to the skilled person, like rotovaporation etc.
[0073] The method of the present invention is very valuable because it is possible to tailor
the extract obtained from the plant substrate. By varying the soap components used
for extraction the composition of the flavourant mixture can be controlled. If an
extract is required that comprises a higher amount of polar compounds, the extraction
mixture will comprise more of low chain soap components. If it is in particular the
highly hydrophobic part of the fatty phase of a plant substrate that is required,
soap components having a long chain are used.
[0074] On the other hand, the method of the present invention allows to tailor the extract
by using only one specific fatty acid soap that extracts a specific part of the odoriferous
agents. Thereby an extract with foreseeable composition can be obtained or a selective
extraction is possible. It has been found that when extracting
Iridaceae plant material a major part of irones can be obtained by using only myristic acid
soap in aqueous solution.
[0075] Only with some routine experiments it is possible to tailor the extract or the composition
of the flavourant mixture that is deemed to be most pleasant. In this way, it is also
possible to obtain reproducible flavour compositions.
[0076] The material to be extracted can be either a plant or parts thereof or it can also
be an extract which had been extracted before with conventional means. For example,
the plant substrate can be an iris extract, iris extraction waste or iris plant tissue.
[0077] The extraction method of the present invention is characterized by the use of at
least one soap component or a combination of two or more soap components or a combination
of at least one soap component and at least one hydrotropic additive. The different
components differ e.g. by the number of carbon atoms in the fatty acid chain and/or
by the counter ion. Preferably, the mixture of soap components comprises soap compounds
having chains with a different length, i.e. different number of n. It has been found
that a surprisingly good mixture is a composition of M
+C
4-, M
+C
8- and M
+C
14-. Instead of M
+C
14- a longer chain soap can be used as long as it is miscible in the extraction medium.
M
+C
16- or a branched variant of fatty acids like isovalerianic acid are also considered.
[0078] The counter ion also has an influence on the solubility of the soap component in
the extraction system. It has been found that cholinium soap components are particularly
useful because cholinium as counter ion increases the solubility of the soap component
in the extraction medium. Other counter ions which have a lower basicity are also
contemplated. Usually the soap components that are used in the present extraction
medium are sodium or potassium salts of fatty acids. Potassium salts have the advantage
that they can be used at lower temperatures than sodium salts, this allows to extract
at lower temperature which is favourable for the extraction of temperature sensitive
odoriferous compounds.
[0079] Surprisingly, the extraction medium of the present invention allows very short extraction
cycles. It has been found that a extraction time of 30 minutes or less allows to extract
all valuable compounds from plant material. For example, if powdered
Iridaceae rhizome is used as plant substrate, 30 minutes of contact with the soap composition
is enough to more or less fully extract all valuable components. A very rich flavour
mixture is obtained if a composition of C
4, C
8 and C
14 is used.
[0080] Some plant substrates are very valuable and in this case it is worth to reprocess
extraction waste which has been produced with other methods or to repeatedly extract
the substrate.
[0081] The extract obtained with the method of the present invention is ready to use for
many applications, in particular for use in cosmetic and scenting compositions. As
those compositions usually comprise fatty substances the fatty acid comprising extract
obtained with the method of the present invention is compatible and can be directly
added without separating fatty acids.
[0082] Some embodiments of the present invention are further explained in the following
examples.
Example 1
[0083] An extract of rhizomes of
Iridaceae was prepared. Rhizomes were crushed to obtain a fine powder. The plant powder was
contacted with an aqueous extracting solution in a ratio of 30 g solvent per gram
rhizome to compensate swelling of the rhizome. Three plant powder samples were extracted
with three different extraction solutions. In a first run, 12.5 wt.-% sodium butanoate
(NaC
4) was contacted with the rhizome for 30 min. In a second run, rhizome was contacted
with 1.5 wt.-% sodium myristate (NaC
14) at 45°C. In a third run rhizome was contacted with 3.7 wt.-% Na oleate (NaC
18) for 30 min at 25°C.
[0084] The results are shown in Fig. 1. It can be seen that the concentration of the sodium
carboxylate is in correlation with the extraction efficiency. If a low concentration
of the soap compound was used, the yield was only slightly higher than for an extraction
with pure water. As soon as the concentration of the soap compound(s) in the extracting
medium reached the CMC, i.e. the critical micelle concentration, the yield increased
significantly. Furthermore, a correlation between the chain length of the fatty acid
and the efficiency was found. If a short chain fatty acid salt was used, a higher
concentration was necessary, whereas a lower concentration of the fatty acid salt
could be used if a soap with a longer chain was used. It was found that sodium myristate
was particularly useful as extracting agent. This is also shown in Fig. 2.
[0085] The extract obtained was analyzed and it was found that when using
Iris pallida rhizome, 640 ± 40 mg/kg irones were obtained.
[0086] Furthermore it was found that the composition of fractions obtained by using different
soap compounds varied. The shorter and the more hydrophilic the soap was, the more
polar compounds were extracted. If an extraction was made with long chain soaps, less
polar substances were obtained. Thus, by varying the chain length of the soap compound
or by using a combination of more than one fatty acid soap with differing chain length
the composition of the fraction obtained by the extraction can be controlled. These
results can be seen in Fig. 3 and 4.
[0087] In a further example, a combination of NaC
4, NaC
8 and NaC
14 was used for extraction. Surprisingly it was found that this ternary combination
had such a low dissolution temperature, that it could be used at room temperature,
whereas a combination without NaC
8 had to be heated to obtain a solution. Using the ternary combination resulted in
an extract with a very pleasant flavor.
[0088] Soap extracts obtained from different samples were further worked up to obtain flavour
mixtures.
[0089] In one approach, a sample of a soap extract was mixed with diethyl ether to isolate
the fragrance. The solvent afterwards was evaporated.
[0090] The remaining soap extracting solution was used again for extracting iris rhizomes.
Thus, the soap extracting solution can be recycled.
[0091] In a second approach the soap extract was neutralized by adding an amount of an acid
to lower the pH value. By adding the acid the micelles are broken und the fatty acids
separate together with the odoriferous agents as upper oily phase and can be isolated.
[0092] In a third approach, a solution of a calcium or magnesium salt was added to the soap
extract. Thereby, the fatty acids were precipitated as calcium or magnesium salts
and could be separated, for example by filtration. The precipitate was dried and thereafter
contacted with ethanol. The odoriferous agents, in particular the irones were dissolved
by ethanol, whereas the calcium or magnesium fatty acid salts were not dissolved.
After filtration an extract comprising odoriferous agents was obtained with a very
pleasant odour.
Example 2
[0093] Plant parts of rose and jasmine were used to obtain a fragrancy. Blossoms of rose
and of jasmine were frozen and then ground to a fine powder. The blossom powder was
contacted with an extraction medium as described in Example 1. Extraction was carried
out for 30 min. The soap extract obtained had a very pleasant rose-like or jasmine-like,
respectively, scent.
Example 3
[0094] Orris butter as obtained in Example 1 by extraction with sodium butanoate or sodium
myristate was analyzed with GC-MS. The spectra are shown in Fig. 3 and 4. As can be
seen in Fig. 3 the composition of the extracts differs with regard to key compounds.
The extract obtained with sodium myristate contains irones (7583-7586), but no polar
compounds, whereas the extract obtained with sodium butanoate contains the polar compound
acetovanillin (7470), but only few irones. Thus, to obtain full flavour it is preferable
to use both soaps for extraction, preferably combined with a third soap and/or an
additive, whereas for extraction of the irones in more or less quantitative amount
extraction with only NaC
14 is preferred.
1. Process for isolation of at least one odoriferous agent from a plant substrate comprising
a) contacting a plant substrate with an aqueous soap extraction solution comprising
an aqueous medium and at least one soap compound R-C(=O)O-M+ or +M-O(O=)C-R-C(=O)O-M+, wherein R is saturated or unsaturated linear, branched or cyclic C3 to C17 alkyl or C6 to C18 aryl, wherein the alkyl or aryl group can be substituted with up to 5 functional
groups, and wherein M+ is a monovalent cation, to obtain a soap extract and
b) isolating a flavour mixture comprising at least one odoriferous agent from the
soap extract obtained in step a).
2. Process according to claim 1 for isolation of at least one odoriferous agent from
an Iridaceae substrate, a rose substrate or a jasmine substrate.
3. Process according to claim 2, wherein an Iridaceae substrate is a substrate from Iris germanica, Iris pallida, Iris pallida argentea variegata, Iris pallida aurea
variegata, Iris pallida alba, Iris neglecta, Iris spectabilis, Iris macedonica, or Iris florentina and /or other varieties of the species Iris barbata.
4. Process according to one of the preceding claims, wherein the substrate is iris rhizome,
iris extracts, iris extraction wastes, iris plant tissue, or a mixture thereof, rose
blossoms and/or leaves, jasmine blossoms and/or leaves; which optionally are in particulate,
crushed or powdered form.
5. Process according to one of the preceding claims, wherein the odoriferous agent comprises
α-irone, β-irone, γ-irone or any mixture thereof.
6. Process according to one of the preceding claims, wherein M+ is sodium, potassium, ammonium or cholinium.
7. Process according to one of the preceding claims, wherein the aqueous soap dispersion
comprises at least one soap compound R-C(=O)O-M+, wherein R is CH3(CH2)n, wherein n is 2 to 14, and wherein M+ is a monovalent cation.
8. Process according to one of the preceding claims, wherein additionally at least one
hydrotropic additive is added to the soap extracting solution.
9. Process according to claim 8, wherein the hydrotropic additive is selected from a
fatty alcohol, C6-C12 dicarboxylic acid or a salt or ester thereof, a C6-C12 hydroxy carboxylic acid or a salt or ester thereof, a branched or cyclic C6-C18 fatty acid or a salt or ester thereof, or a mixture thereof.
10. Process according to one of the preceding claims, wherein an aqueous soap extracting
solution comprising a mixture of at least two different soap compounds is used, wherein
the compounds differ by the number of n and/or the type of the cation.
11. Process according to one of the preceding claims, wherein the aqueous soap extracting
solution comprises at least water, sodium myristate and/or potassium myristate.
12. Process according to one of the preceding claims, wherein for isolating a flavour
mixture in step b)
i) the pH value and/or the temperature of the soap extract obtained in step a) are
changed to separate at least part of the fatty acid and the flavour ingredients; or
ii) di- or polyvalent cations are added to the soap extract to precipitate at least
part of the fatty acids as salt; or
iii) the soap extract obtained in step a) is extracted with a lipophilic solvent and
optionally the solvent is removed.
13. Process according to one of the preceding claims, wherein an aqueous soap extracting
solution comprising soaps of those fatty acids that are present in in the plant substrate
is used.
14. Process according to one of the preceding claims, wherein the composition of the flavour
mixture is controlled by using an aqueous soap extracting solution with a predetermined
number and type of soap components or a combination of one or more soap components
and one or more additives.
15. Process for extracting a composition with a predetermined percentage of lipophilic
and hydrophilic odoriferous ingredients from a plant substrate wherein a soap dispersion
is used comprising at least one myristate soap and at least one hydrotropic additive.
1. Verfahren zur Isolierung von mindestens einem Riechstoff aus einem Pflanzensubstrat,
umfassend
a) Inkontaktbringen eines Pflanzensubstrats mit einer wässrigen Seifenextraktionslösung,
die ein wässriges Medium und mindestens eine Seifenverbindung R-C(=O)O-M+ oder +M-O(O=)C-R-C(=O)O-M+ aufweist, wobei R gesättigtes oder ungesättigtes lineares, verzweigtes oder zyklisches
C3- bis C17-Alkyl oder C6- bis C18-Aryl ist, wobei die Alkyl- oder Arylgruppe mit bis zu 5 funktionellen Gruppen substituiert
sein kann, und wobei M+ ein einwertiges Kation ist, um einen Seifenextrakt zu erhalten und
b) Isolieren einer Aromamischung, die mindestens ein Riechmittel, das aus dem in Schritt
a) erhaltenen Seifenextrakt erhalten wird, aufweist.
2. Verfahren nach Anspruch 1 zur Isolierung von mindestens einem Riechstoff aus einem
Iridaceae-Substrat, einem Rosensubstrat oder einem Jasminsubstrat.
3. Verfahren nach Anspruch 2, wobei ein Iridaceae-Substrat ein Substrat aus Iris germanica, Iris pallida, Iris pallida argentea variegata, Iris pallida aurea
variegata, Iris pallida alba, Iris neglecta, Iris spectabilis, Iris macedonica, oder Iris florentina und/oder anderen Sorten der Art Iris barbata ist.
4. Verfahren nach einem der vorhergehenden Ansprüche, wobei das Substrat Iris-Rhizom,
Iris-Extrakte, Iris-Extraktionsabfälle, Iris-Pflanzengewebe, oder eine Mischung davon,
Rosenblüten und/oder -blätter, Jasminblüten und/oder -blätter ist; die wahlweise in
partikulärer, zerkleinerter oder pulverisierter Form vorliegen.
5. Verfahren nach einem der vorhergehenden Ansprüche, wobei das Riechmittel α-Iron, β-Iron,
γ-Iron oder ein beliebiges Gemisch davon aufweist.
6. Verfahren nach einem der vorhergehenden Ansprüche, wobei M+ Natrium, Kalium, Ammonium oder Cholinium ist.
7. Verfahren nach einem der vorhergehenden Ansprüche, wobei die wässrige Seifendispersion
mindestens eine Seifenverbindung R-C(=O)O-M+ aufweist, wobei R CH3(CH2)n ist, wobei n 2 bis 14 ist, und wobei M+ ein einwertiges Kation ist.
8. Verfahren nach einem der vorhergehenden Ansprüche, wobei der Seifenextraktionslösung
zusätzlich mindestens ein hydrotropes Additiv zugesetzt wird.
9. Verfahren nach Anspruch 8, wobei das hydrotrope Additiv ausgewählt ist aus einem Fettalkohol,
C6-C12-Dicarbonsäure oder einem Salz oder Ester davon, einer C6-C12-Hydroxycarbonsäure oder einem Salz oder Ester davon, einer verzweigten oder zyklischen
C6-C18-Fettsäure oder einem Salz oder Ester davon, oder einer Mischung davon.
10. Verfahren nach einem der vorhergehenden Ansprüche, wobei eine wässrige Seifenextraktionslösung
verwendet wird, die eine Mischung aus mindestens zwei verschiedenen Seifenverbindungen
aufweist, wobei sich die Verbindungen in der Anzahl n und/oder der Art des Kations
unterscheiden.
11. Verfahren nach einem der vorhergehenden Ansprüche, wobei die wässrige Seifenextraktionslösung
mindestens Wasser, Natriummyristat und/oder Kaliummyristat aufweist.
12. Verfahren nach einem der vorhergehenden Ansprüche, wobei zum Isolieren einer Aromamischung
in Schritt b)
i) der pH-Wert und/oder die Temperatur des in Schritt a) erhaltenen Seifenextrakts
geändert werden, um mindestens einen Teil der Fettsäure und der Aromabestandteile
abzutrennen; oder
ii) dem Seifenextrakt zwei- oder mehrwertige Kationen zugesetzt werden, um mindestens
einen Teil der Fettsäuren als Salz auszufällen; oder
iii) der in Schritt a) erhaltene Seifenextrakt mit einem lipophilen Lösungsmittel
extrahiert und gegebenenfalls das Lösungsmittel entfernt wird.
13. Verfahren nach einem der vorhergehenden Ansprüche, wobei eine wässrige Seifenextraktionslösung
verwendet wird, die Seifen der im Pflanzensubstrat vorhandenen Fettsäuren aufweist.
14. Verfahren nach einem der vorhergehenden Ansprüche, wobei die Zusammensetzung der Aromamischung
unter Verwendung einer wässrigen Seifenextraktionslösung mit einer vorbestimmten Anzahl
und Art von Seifenkomponenten oder einer Kombination aus einer oder mehreren Seifenkomponenten
und einem oder mehreren Additiven kontrolliert wird.
15. Verfahren zum Extrahieren einer Zusammensetzung mit einem vorbestimmten Prozentsatz
an lipophilen und hydrophilen Riechstoffen aus einem Pflanzensubstrat, wobei eine
Seifendispersion verwendet wird, die mindestens eine Myristatseife und mindestens
ein hydrotropes Additiv aufweist.
1. Procédé d'isolement d'au moins un agent odorifère à partir d'un substrat végétal,
comprenant
a) la mise en contact d'un substrat végétal avec une solution d'extraction aqueuse
à base de savon comprenant un milieu aqueux et au moins un composé de savon R-C(=O)O-M+ ou +M-O(O=)C-R-C(=O)O-M+, où R est C6 à C18-aryle ou C3 à C17-alkyle saturé ou insaturé, linéaire, ramifié ou cyclique, où le groupement alkyle
ou aryle peut être substitué par jusqu'à 5 groupements fonctionnels, et où M+ est un cation monovalent, afin d'obtenir un extrait de savon, et
b) l'isolement d'un mélange d'arômes comprenant au moins un agent odorifère, à partir
de l'extrait de savon obtenu dans l'étape a).
2. Procédé selon la revendication 1, destiné à l'isolement d'au moins un agent odorifère
à partir d'un substrat d'Iridaceae, d'un substrat de rose ou d'un substrat de jasmin.
3. Procédé selon la revendication 2, dans lequel un substrat d'Iridaceae est un substrat issu d'Iris germanica, d'Iris pallida, d'Iris pallida argentea variegata, d'Iris pallida aurea variegata, d'Iris pallida alba, d'Iris neglecta, d'Iris spectabilis, d'Iris macedonica, ou d'Iris florentina, et/ou d'autres variétés de l'espèce Iris barbata.
4. Procédé selon l'une des revendications précédentes, dans lequel le substrat est constitué
de rhizomes d'iris, d'extraits d'iris, de résidus d'extraction d'iris, de tissus de
plantes d'iris, ou d'un mélange de ceux-ci, de fleurs et/ou de feuilles de rose, de
fleurs et/ou de feuilles de jasmin ; qui se trouvent éventuellement sous forme particulaire,
broyée ou pulvérulente.
5. Procédé selon l'une des revendications précédentes, dans lequel l'agent odorifère
comprend de l'α-irone, de la β-irone, de la γ-irone, ou un mélange quelconque de celles-ci.
6. Procédé selon l'une des revendications précédentes, dans lequel M+ est le sodium, le potassium, l'ammonium ou le cholinium.
7. Procédé selon l'une des revendications précédentes, dans lequel la dispersion de savon
aqueuse comprend au moins un composé de savon R-C(=O)O-M+, où R est CH3(CH2)n, où n va de 2 à 14, et où M+ est un cation monovalent.
8. Procédé selon l'une des revendications précédentes, dans lequel, de plus, au moins
un additif hydrotrope est ajouté à la solution d'extraction de savon.
9. Procédé selon la revendication 8, dans lequel l'additif hydrotrope est choisi parmi
un alcool gras, un acide C6-C12-dicarboxylique ou un sel ou ester de celui-ci, un acide C6-C12-hydroxycarboxylique ou un sel ou ester de celui-ci, un acide gras en C6-C18 ramifié ou cyclique ou un sel ou ester de celui-ci, ou un mélange de ceux-ci.
10. Procédé selon l'une des revendications précédentes, dans lequel on utilise une solution
d'extraction aqueuse à base de savon comprenant un mélange d'au moins deux composés
de savon différents, où les composés diffèrent par le nombre de n et/ou le type du
cation.
11. Procédé selon l'une des revendications précédentes, dans lequel la solution d'extraction
aqueuse à base de savon comprend au moins de l'eau, du myristate de sodium et/ou du
myristate de potassium.
12. Procédé selon l'une des revendications précédentes, dans lequel, pour l'isolement
d'un mélange d'arômes dans l'étape b)
i) la valeur de pH et/ou la température de l'extrait de savon obtenu dans l'étape
a) sont changés pour séparer au moins une partie de l'acide gras et des ingrédients
d'arôme; ou
ii) des cations di- ou polyvalents sont ajoutés à l'extrait de savon afin de précipiter
au moins une partie des acides gras sous forme de sel; ou
iii) l'extrait de savon obtenu dans l'étape a) est extrait par un solvant lipophile
et éventuellement le solvant est éliminé.
13. Procédé selon l'une des revendications précédentes, dans lequel on utilise une solution
d'extraction aqueuse à base de savon comprenant des savons des mêmes acides gras présents
dans le substrat végétal.
14. Procédé selon l'une des revendications précédentes, dans lequel la composition du
mélange d'arômes est contrôlée par l'utilisation d'une solution d'extraction aqueuse
à base de savon ayant un nombre et un type prédéterminés de composants de savon ou
une combinaison d'un ou plusieurs composants de savon et d'un ou plusieurs additifs.
15. Procédé d'extraction d'une composition ayant un pourcentage prédéterminé d'ingrédients
odorifères lipophiles et hydrophiles à partir d'un substrat végétal, où on utilise
une dispersion de savon comprenant un savon à base de myristate et au moins un additif
hydrotrope.