Obtaining a juice of fresh plants by thermomechanical treatment and cosmetic and therapeutic use thereof

Abstract

The present invention relates to a process for obtaining a juice of fresh plants, characterized in that said fresh plants, with the exclusion of the seeds only, are subjected to a thermomechanical treatment consisting in extruding the fresh plants in an extruder, combined with a heat treatment which makes it possible to inactivate the endogenous enzymes and to preserve the molecules of compounds of interest in the native form thereof, in the absence of solvent, followed by a juice recovery operation.

Claims

1. A process to obtain a juice of fresh plants wherein said fresh plants with the exclusion of the sole seeds of the plants are subjected to a solvent-free thermomechanical treatment whereby the fresh plants are extruded in an extruder which is also heated with a heat treatment allowing inactivation of the endogenous enzymes and preserving of the molecules of the compounds of interest in their native form, followed by a juice recovery operation, wherein the thermomechanical treatment is performed in a twin screw extruder which has a first co-rotating and co-penetrating twin screw zone wherein trituration of said plant takes place and wherein the twin screw extruder also has a second twin screw zone wherein solid/liquid separation takes place and wherein said first co-rotating and co-penetrating twin screw zone has several barrels the temperatures of which are regulated to obtain a temperature of 60 C. to 300 C.

2. The process according to claim 1, wherein the temperature is 60 to 120 C.

Description

EXAMPLE 1

(1) 12.75 kg of unfrozen (24 h at 2 C.) fresh above-ground parts of oats (Avena sativa L.) harvested by harvester after a growth period of 2 months (oat seedlings) were fed into the first barrel of a five-barrel twin-screw extruder with co-rotating, co-penetrating screwsCLEXTRAL BC45. The temperatures applied to the different barrels were 30 C./120 C./120 C./120 C./60 C.

(2) The scheme of the process was as follows (total duration of extrusion step=20 min; treatment rate: 38 kg plants/h and 22 kg juice/h):

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(4) After extrusion, 57.2% juice w/w was obtained relative to the starting material. Clarification and filtration steps were then conducted to obtain a clear juice with a final juice yield of 53.1% containing 11% dry matter i.e. a yield of extracted dry matter of 5.8% (w/w).

(5) The juice yield by pressing (crushingpressingfiltration) of the same raw material was 50%, containing 4.5% dry matter i.e. a yield of 2.25% (w/w).

(6) The extrusion technology therefore allows more juice to be obtained, the juice having a higher compound content, bioactive compounds in particular. The flavonoid content of the juice obtained in Example 1 was 0.26%, whereas it was only 0.02% in the juice obtained by pressing the same raw material. The flavonoid content was therefore multiplied by 10 in this case.

(7) The advantage of hot extrusion can also be pointed out for flavonoid content: the temperature allows the extraction of more compounds (including four times more flavonoids) and the obtaining of native molecules non-denatured by enzymes.

(8) This was also observed with oat saponins, avenacosides, which are rapidly deglucosylated by pressing. The native molecules are found solely with thermomechanical treatment: the juices obtained by extrusion at 120 C. and 200 C. contained avenacosides (A and B) in a proportion of 89 mg and 93 mg per 100 g of dry matter. They were therefore not degraded by endogenous deglucosidases.

(9) TABLE-US-00001 Yield Juice DM/fresh % flavonoids yield* DM plant /DM /juice /FM Technique Parameters % Avenacosides Pressing Crushing then 51 3.78 1.94 0.44 0.02 0.01 Degluco wine press, avenacosides then filtration Extrusion 25 C. 59.70 7.50 4.47 0.80 0.06 0.04 0% 120 C. 53.13 11 5.84 2.40 0.26 0.15 89 mg % g DM 200 C. 48.07 10 4.81 2.30 0.22 0.12 93 mg % DM Extraction 1H reflux 3.10 1.10 0.03 H20 *after filtration

EXAMPLE 2

(10) 3.14 kg of unfrozen (18 h at 2 C.) fresh Echinaceae flower heads (Echinacea purpurea (L.) Moench) were fed into the first barrel of the five-barrel twin-screw extruder with co-rotating, co-penetrating screwsCLEXTRAL BC45. The temperatures applied to the different barrels were 100 C./100 C./100 C./100 C./60 C.

(11) The process and mass balance are given in the Table below (total time of extrusion step: 25 min; treatment rate: 7 kg plants/h and 3 kg juice/h):

(12) TABLE-US-00002 MASS BALANCE PROCESS DRY MATTER 100 FRESH PLANT 48.1 EXTRUSION 16.20% 26.9 CLARIFICATION 10.81% 25 FILTRATION 10.09%

(13) After extrusion, we therefore obtained 48.1% juice w/w relative to the starting material. Clarification and filtration steps were then performed to obtain a clear juice with final juice yield of 25% containing 10.09% dry matter i.e. a dry matter yield of 2.5% (w/w).

(14) The caffeic acid content of this juice was:

(15) cichoric acid: 1.7%/dry matter i.e. 0.17% w/v caftaric acid: 1.21% i.e. 0.12% w/v

(16) When the juice is extruded at ambient temperature, the content of cichoric and caftaric acid is practically zero due to action of the enzymes. When the juice is obtained by pressing fresh flower heads the content of these molecules is also zero.

(17) The enzymes released when pressing (phenoloxidases) rapidly oxidize these molecules (Nsslein B., Kurzmann M., Bauer R., Kreis W. Enzymatic degradation of Cichoric acid in Echinacea purpurea preparations (2000) J. Nat. Prod., 63, pp. 1615-1618, R. Bauer Standardization of Echinacea purpurea Expressed Juice with Reference to Cichoric Acid and Alkamides, Journal of herbs, Spices & Medicinal Plants Vol. 6, lss. 3, 1999).

(18) When extrusion is conducted at ambient temperature or <60 C., the enzymes are not inactivated and degrade the molecules of interest. In this example, solely extrusions performed at 100 C. or 200 C. allowed extraction from the plant of cichoric and caftaric acids without degradation thereof (see summary Table).

(19) Most of the Echinaceae juices available on the market do not contain these molecules, only alcohol-extracted, dried above-ground parts contain these active compounds.

(20) It can also be pointed out that the extrusion process, which as sole solvent uses the water naturally contained in the plant, allows the extraction of far more compounds of interest than aqueous extraction.

(21) TABLE-US-00003 Expressed/ Expressed/ DM/ dry matter fresh plant Juice fresh plant Caftaric Cichoric Caftaric Cichoric Technique yield % DM yield acid acid acid acid Parameters % mg/g Pressing Crushing 36 7.21 2.60 0.00 0.00 0 0 then wine press Extrusion 20 C. 26.7 8.41 2.24 0.06 0.04 0.014 0.009 100 C. 25.0 10.09 2.72 1.21 1.70 0.33 0.46 200 C. 12.46 12.90 1.61 1.96 3.61 0.33 0.61 Dried plant Water under 4.73 0.22 0.05 0.1 0.023 extraction reflux

EXAMPLE 3

(22) 5.11 kg of unfrozen (20 h at 2 C.) fresh, above-ground parts of Lemon Balm (Melissa officinalis L.) were fed into the first barrel of a five-barrel twin-screw extruder with co-rotating and co-penetrating screwsCLEXTRAL BC45. The temperatures applied to the different barrels were 120 C./120 C./120 C./120 C./60 C. The process and mass balance are given in the Table below (duration of extrusion step: 7 min; treatment rate: 46 kg plants/h and 29 kg juice/h):

(23) TABLE-US-00004 MASS BALANCE PROCESS DRY MATTER 100 FRESH PLANT 62.7 EXTRUSION 49.2 CLARIFICATION 48.8 FILTRATION 6.5%

(24) Under these conditions, extrusion allowed juice to be obtained having a yield close to 50% and containing 6.5% dry matter. This matter inter alia contained rosmarinic acid usually extracted by hydroalcoholic mixtures such as 70% ethanol. The rosmarinic acid content of the dry matter extracted by extrusion without any organic solvent was 2.4% (w/w), i.e. comparable with 70% ethanol extraction.

EXAMPLE 4

(25) 4.5 kg of fresh ginger rhizomes (Zingiber officinale Roscoe) were fed into the first barrel of a twin-screw extruder with co-rotating and co-penetrating screwsCLEXTRAL BC45. The temperatures applied to the different barrels were 60 C./60 C./60 C./60 C./60 C. The process and mass balance are given in the Table below:

(26) TABLE-US-00005 MASS BALANCE PROCESS DRY MATTER 100 FRESH PLANT 58.9 EXTRUSION 50.83 CLARIFICATION 50.8 FILTRATION 5.2%
(total time of extrusion step: 5 min; treatment rate: 54 kg plants/h and 32 kg juice/h)

EXAMPLE 5

(27) 5.32 kg of fresh curcuma rhizomes (Curcuma longa L.) were fed into the first barrel of a twin-screw extruder with co-rotating and co-penetrating screwsCLEXTRAL BC45. The temperatures applied to the different barrels were 120 C./120 C./120 C./120 C./120 C. The process and mass balance are given in the Table below (total time of extrusion step: 10 min; treatment rate: 32 kg plants/h and 13 kg juice/h).

(28) TABLE-US-00006 MASS BALANCE PROCESS DRY MATTER 100 FRESH PLANT 40.6 EXTRUSION 34.6 CLARIFICATION 7.5%

(29) The juice obtained was not filtered to preserve the lipophilic compounds in suspension extracted by extrusion: curcumin and derivatives.

(30) Assay showed that the content thereof in the juice obtained was high (8.36%), higher than the content in the dry matter of a commercially available juice (4.52%, containing curcuma juice and citric acid).

(31) TABLE-US-00007 Juice % Curcumin Curcumin Technique yield DM (w/v) (w/DM) Parameters % marketed Freezing/Unfreezing/ 4.01 0.181 4.52 juice DIC*/pressing/ stabilisation with citric acid Extrusion 120 C. 34.6 7.5 0.627 8.36 *DIC = Detente Instantanee Controlee (Instant controlled pressure drop)

EXAMPLE 6

(32) 20.5 kg of unfrozen, fresh above-ground parts of Plantago lanceolate (76% humidity) were fed into the first barrel of a five-barrel twin-screw extruder with co-rotating and co-penetrating screwsClextral BC455. The temperatures applied to the different barrels were 120 C. 43.8% juice was obtained at the outlet of the extruder.

(33) The process and mass balance are given in the Table below:

(34) TABLE-US-00008 PROCESS MASS BALANCE DM Unfrozen plant 100 Extrusion 45.4 8.11% Centrifugation 42.3 7.34% Filtration AF 15 41.4 UF 0.3 38.4 Filtration AF 140 36.6 7.11% UF 10 kDa 6.20%
An ultra-filtration step allowed a sap to be obtained of improved organoleptic quality. This sap contained 6.2% dry matter. This dry matter contained the active ingredients of interest: iridoids (1.8%) and phenolic acids (0.3%). These values are close to those obtained with a 30% EtOH hydroalcoholic extract and higher than with an aqueous extract. We therefore obtained a solvent-free extract of equivalent quality to a hydroalcoholic extract.

EXAMPLE 7

(35) 18.8 kg of unfrozen, fresh above-ground parts of Urtica dioica (76% humidity) were fed into the first barrel of a five-barrel twin-screw extruder with co-rotating and co-penetrating screwsClextral BC45. The temperature applied to the different barrels was 120 C. 9.4 kg of juice were obtained at the outlet of the extruder, corresponding to a yield of 50%.

(36) This juice, containing 5.7% dry matter after centrifugation, can be used as such after pasteurisation.

(37) TABLE-US-00009 Example 8: capsule Lemon balm juice as in Example 3, freeze-dried 200 mg Starch 45 mg Magnesium stearate 2 mg

(38) TABLE-US-00010 Example 9: cream weight % Oat juice as in Example 1 1-5% Tribehenin PEG-20 esters 2-7% Isodecyl neopentanoate 2-9% Glycerine 0.5-10% Glycol palmitate 1-6% Cetyl alcohol 0.5-3% Disodium EDTA 0.05-0.25% Preserving agents 0.5-3% Flavouring 0.2-0.5% Xanthan gum 0.1-0.4% Water qs