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Title:
PROCESS FOR THE MANUFACTURE OF AN EXTRACT CONTAINING LYCOPENE
Document Type and Number:
WIPO Patent Application WO/2019/122444
Kind Code:
A1
Abstract:
The present invention is directed to processes for the manufacture of extracts containing lycopene, as well as to the thus obtained extracts. One process according to the present invention comprises the following steps: a) providing tomato pomace comprising tomato peels and tomato seeds or providing tomato peels; b) adding water to the tomato pomace or to the tomato peels to obtain an aqueous suspension; c) treating the aqueous suspension obtained in step b) with at least one enzyme to obtain an enzyme-treated reaction mixture; d) adding an organic solvent to the enzyme-treated reaction mixture obtained in step c) to obtain a mixture; e) separating solids from the mixture obtained in step d) to obtain a biphasic mixture with an aqueous phase and an organic solvent phase; f) separating the aqueous phase and the organic solvent phase to obtain the organic solvent phase; g) separating the organic solvent from the organic solvent phase to obtain an oily extract containing lycopene in an amount of at least 1.5 weight-%, based on the total weight of the oily extract; h) optionally recycling the organic solvent obtained in step g) back into step d); i) crystallizing the oily extract obtained in step g) with an anti-solvent and separating the resulting crystals from the mother liquor by centrifugation or filtration, preferably by centrifugation; j) drying the crystals obtained in step i) to obtain crystals containing lycopene in an amount of at least 40 weight-%, based on the total weight of the crystals; whereby preferably step i) is repeated at least once and more preferably at least twice.

Inventors:
MUSSLER, Bernd (Patent DepartmentWurmisweg 576, 4303 Kaiseraugst, 4303, CH)
WIESER, Marco (Patent DepartmentWurmisweg 576, 4303 Kaiseraugst, 4303, CH)
Application Number:
EP2018/086818
Publication Date:
June 27, 2019
Filing Date:
December 21, 2018
Export Citation:
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Assignee:
DSM IP ASSETS B.V. (Het Overloon 1, 6411 TE HEERLEN, 6411 TE, NL)
International Classes:
C07C11/21; A23L19/00; C07C7/10
Foreign References:
EP2338355A12011-06-29
US20030044499A12003-03-06
US7572468B12009-08-11
US20050153038A12005-07-14
CN1403506A2003-03-19
US5871574A1999-02-16
EP2338355A12011-06-29
US20030044499A12003-03-06
US5871574A1999-02-16
US7572468B12009-08-11
Attorney, Agent or Firm:
STECK, Melanie (DSM Nutritional Products Ltd, Patent DepartmentWurmisweg 576, 4303 Kaiseraugst, 4303, CH)
Download PDF:
Claims:
Claims

1 . A process for the manufacture of an extract containing lycopene

comprising the following steps: a) providing tomato pomace comprising tomato peels and tomato seeds or providing tomato peels;

b) adding water to the tomato pomace or to the tomato peels to obtain an aqueous suspension;

c) treating the aqueous suspension obtained in step b) with at least one

enzyme to obtain an enzyme-treated reaction mixture;

d) adding an organic solvent to the enzyme-treated reaction mixture obtained in step c) to obtain a mixture;

e) separating solids from the mixture obtained in step d) to obtain a biphasic mixture with an aqueous phase and an organic solvent phase;

f) separating the aqueous phase and the organic solvent phase to obtain the organic solvent phase;

g) separating the organic solvent from the organic solvent phase to obtain an oily extract containing lycopene in an amount of at least 1 .5 weight-%, based on the total weight of the oily extract;

h) optionally recycling the organic solvent obtained in step g) back into step d); i) crystallizing the oily extract obtained in step g) with an anti-solvent and separating the resulting crystals from the mother liquor by centrifugation or filtration, preferably by centrifugation;

j) drying the crystals obtained in step i) to obtain crystals containing lycopene in an amount of at least 40 weight-%, based on the total weight of the crystals;

whereby preferably step i) is repeated at least once and more preferably at least twice.

2. The process according to claim 1 , wherein only part of the extract

obtained in step g) is treated according to steps i) and j) to obtain the crystals, and which comprises an additional step k) carried out after step j): k) mixing the oily extract containing lycopene in an amount of at least 1 .5 weight-%, based on the total weight of the oily extract, as obtained in step g) with the crystals containing lycopene in an amount of at least 40 weight- %, based on the total weight of the crystals, as obtained in step j) to obtain an oily extract containing lycopene in an amount of at least 5 weight-%, based on the total weight of the oily extract.

3. The process according to claim 1 and/or 2, wherein the tomato pomace used in step a) is obtained as by-product in the tomato processing industry such as the manufacture of tomato sauces, tomato pastes, tomato purees, tomato ketchups, tomato juices, and concentrates thereof.

4. The process according to any one or more of claims 1 to 3, wherein step i) is repeated 1 to 3 times.

5. The process according to any one or more of claims 1 to 4, wherein the enzyme used in step c) is a pectinase.

6. The process according to any one or more of claims 1 to 5, wherein an additional enzyme is used in step c), and wherein this additional enzyme is a hemicellulase and/or a cellulase.

7. The process according to any one or more of claims 1 to 6, wherein the total concentration of the enzyme used is preferably in the range of from 0.005 to 1 weight-%, more preferably in the range of from 0.007 to 0.5 weight-%, most preferably in the range of from 0.01 to 0.1 weight-%, based on the weight of the enzyme containing suspension.

8. The process according to any one or more of claims 1 to 7, wherein the organic solvent used in step d) is either ethyl acetate or isobutyl acetate or hexane or heptane or dichloromethane or any mixture thereof, preferably the organic solvent used in step d) is ethyl acetate.

9. The process according to any one or more of claims 1 to 8, wherein the amount of the solvent used in step d) is in the range of from 1 to 3 times the weight of the tomato pomace or tomato peels used as starting material.

10. The process according to any one or more of claims 1 to 9, wherein the anti-solvent used in step i) is either ethanol or isopropanol or methanol or acetone or any mixture thereof, whereby one or more of these anti- solvents may also be mixed with water and said mixture used, preferably wherein the anti-solvent is ethanol.

1 1 . The process according to any one or more of claims 1 to 10, wherein the oily extract containing lycopene obtained in step g) comprises lycopene in an amount in the range of from 1 .5 to 5 weight-%, based on the total weight of the oily extract.

12. The process according to any one or more of the preceding claims

comprising the following steps: a1 ) providing tomato pomace comprising tomato peels and tomato seeds or providing tomato peels;

b1 ) adding water to the tomato pomace or to the tomato peels to obtain an aqueous suspension;

d ) treating the aqueous suspension obtained in step b1 ) with at least one

enzyme to obtain an enzyme-treated reaction mixture;

d1 ) adding an organic solvent to the enzyme-treated reaction mixture obtained in step d ) to obtain a mixture, wherein the organic solvent is either ethyl acetate or isobutyl acetate or hexane or heptane or dichloromethane or any mixture thereof, preferably wherein the organic solvent is ethyl acetate; e1 ) separating solids from the mixture obtained in step d1 ) to obtain a biphasic mixture with an aqueous phase and an organic solvent phase;

f1 ) separating the aqueous phase and the organic solvent phase to obtain the organic solvent phase; g1 ) separating the organic solvent from the organic solvent phase to obtain an oily extract containing lycopene in an amount of at least 1 .5 weight-%, based on the total weight of the oily extract;

hi ) optionally recycling the organic solvent obtained in step g1 ) back into step d1 );

P ) crystallizing the oily extract obtained in step g1 ) with an anti-solvent,

wherein the anti-solvent is either ethanol or isopropanol or methanol or acetone or any mixture thereof, whereby one or more of these anti-solvents may also be mixed with water and said mixture used, preferably wherein the anti-solvent is ethanol, and separating the resulting crystals from the mother liquor by centrifugation or filtration, preferably by centrifugation;

j1 ) drying the crystals obtained in step i1 ) to obtain crystals containing lycopene in an amount of at least 40 weight-%, based on the total weight of the crystals;

whereby preferably step P ) is repeated at least once and more preferably at least twice.

13. The process according to claim 12, wherein only part of the extract

obtained in step g1 ) is treated according to steps P ) and j 1 ) to obtain crystals, and which comprises an additional step k1 ) carried out after step j1 ): k1 ) mixing the oily extract containing lycopene in an amount of at least 1 .5 weight- %, based on the total weight of the oily extract, as obtained in step g1 ) with the crystals containing lycopene in an amount of at least 40 weight-%, based on the total weight of the crystals, as obtained in step j 1 ) to obtain an oily extract containing lycopene in an amount of at least 5 weight-%, based on the total weight of the oily extract. 14. The oily extract containing lycopene in an amount of at least 1 .5 weight-

%, preferably in an amount in the range of from 1 .5 to 5 weight-%, based on the total weight of the oily extract, as obtained either according to the process according to any one or more of claims 1 to 11 when having carried out steps a) to g) or according to the process according to claim 12 or 13 when having carried out steps a1 ) to g1 ).

15. The crystals containing lycopene in an amount of at least 40 weight-%, based on the total weight of the crystals, as obtained either according to the process according to any one or more of claims 1 to 11 when having carried out steps a) to j) or according to the process according to claim 12 or 13 when having carried out steps a 1 ) to j 1 ) . 16. The oily extract containing lycopene in an amount of at least 5 weight-%, based on the total weight of the oily extract, as obtained either according to the process according to any one or more of claims 2 to 1 1 when having carried out steps a) to k) or according to the process according to claim 13 when having carried out steps a1 ) to k1 ).

Description:
Process for the manufacture of an extract containing lycopene

Summary of the invention

The present invention is directed to processes for the manufacture of extracts containing lycopene, as well as to the thus obtained extracts.

Background of the invention

A process for extracting carotenoids such as lycopene from plant matrices such as tomatoes is already known from EP-A 2 338 355. Here, however, an enzyme mixture is needed in a higher amount than in the processes of the present invention. Furthermore, the starting material has to be ground and centrifuged, which is not the case according to the processes of the present invention.

US 2003/0044499 discloses inter alia the extraction of lycopene from tomato pulp, i.e. a different starting material is used than in the present invention. The same applies for the process described in US 5,871 ,574.

In US 7,572,468 the expensive solvent ethyl lactate is used. Furthermore, a lyophilization step is applied. Thus, the process of US 7,572,468 is far too expensive to be enlarged to industrial scale.

Thus, there is a need for an efficient process for the extraction of lycopene from tomato waste such as tomato peels or tomato pomace, whereby the tomato pomace comprises tomato peels and tomato seeds, which can be used at industrial scale. This need is met by the present invention.

Detailed description of the invention

The present invention is directed towards a process for the manufacture of an extract containing lycopene comprising the following steps: a) providing tomato pomace comprising tomato peels and tomato seeds or providing tomato peels;

b) adding water to the tomato pomace or to the tomato peels to obtain an aqueous suspension; c) treating the aqueous suspension obtained in step b) with at least one enzyme to obtain an enzyme-treated reaction mixture;

d) adding an organic solvent to the enzyme-treated reaction mixture obtained in step c) to obtain a mixture;

e) separating solids from the mixture obtained in step d) to obtain a biphasic mixture with an aqueous phase and an organic solvent phase;

f) separating the aqueous phase and the organic solvent phase to obtain the organic solvent phase,

g) separating the organic solvent from the organic solvent phase to obtain an oily extract containing lycopene in an amount of at least 1.5 weight-%, based on the total weight of the oily extract;

h) optionally recycling the organic solvent obtained in step g) back into step d); i) crystallizing the oily extract obtained in step g) with an anti-solvent,

wherein the anti-solvent is preferably an alcohol or a ketone or any mixture thereof, whereby one or more of these anti -solvents may also be mixed with water and said mixture used, and separating the resulting crystals from the mother liquor by centrifugation or filtration, preferably by centrifugation; j) drying the crystals obtained in step i) to obtain crystals containing lycopene in an amount of at least 40 weight-%, based on the total weight of the crystals;

whereby preferably step i) is repeated at least once and more preferably at least twice.

The steps are preferably carried out in the given order.

The extraction of the tomato pomace or the tomato peels with the organic solvent, i.e. steps a) to h) may also be carried out several times, preferably from 1 to 3 times. The crystallization, i.e. step i), may also be carried out several times, preferably from 2 to 3 times in total, whereby different anti-solvents may be used.

If the crystallization step i) is carried out 3 times in total, crystals containing lycopene in an amount of at least 60 weight-%, based on the total weight of the crystals, can be obtained. Furthermore, the present invention is directed to the extracts containing lycopene obtained by such a process.

In an embodiment of the present invention only part of the oily extract obtained in step g) is treated according to steps i) and j) to obtain crystals. The corresponding process comprises an additional step k) carried out after step j):

k) mixing the oily extract containing lycopene in an amount of at least 1 .5 weight-%, based on the total weight of the oily extract, as obtained in step g) with the crystals containing lycopene in an amount of at least 40 weight- %, based on the total weight of the crystals, as obtained in step j) to obtain an oily extract containing lycopene in an amount of at least 5 weight-%, based on the total weight of the oily extract.

In a preferred embodiment of the present invention the process consists only of the steps a) to j), whereby it is not excluded that single steps of these steps may be performed several times. In another preferred embodiment of the present invention the process consists only of the steps a) to k), whereby it is not excluded that single steps of these steps may be performed several times. That means that no other steps than a) to j) or a) to k) are carried out such as e.g. grinding of the starting material which is necessary according to some processes of the prior art.

A further preferred process for the manufacture of an extract containing lycopene according to the present invention comprises the following steps: a1 ) providing tomato pomace comprising tomato peels and tomato seeds;

b1 ) adding water to the tomato pomace to obtain an aqueous suspension;

d ) treating the aqueous suspension obtained in step b1 ) with at least one

enzyme to obtain an enzyme-treated reaction mixture;

d1 ) adding an organic solvent to the enzyme-treated reaction mixture obtained in step d ) to obtain a mixture, wherein the organic solvent is either ethyl acetate or isobutyl acetate or hexane or heptane or dichloromethane or any mixture thereof, preferably wherein the organic solvent is ethyl acetate; e1 ) separating solids from the mixture obtained in step d1 ) to obtain a biphasic mixture with an aqueous phase and an organic solvent phase; f1 ) separating the aqueous phase and the organic solvent phase to obtain the organic solvent phase;

g1 ) separating the organic solvent from the organic solvent phase to obtain an oily extract containing lycopene in an amount of at least 1.5 weight-%, based on the total weight of the oily extract;

hi ) optionally recycling the organic solvent obtained in step g1 ) back into step d1 );

P ) crystallizing the oily extract obtained in step g1 ) with an anti-solvent,

wherein the anti-solvent is ethanol or isopropanol or methanol or acetone or any mixture thereof, whereby one or more of these anti-solvents may also be mixed with water and said mixture used, preferably wherein the anti solvent is ethanol, and separating the resulting crystals from the mother liquor by centrifugation or filtration, preferably by centrifugation;

j 1 ) drying the crystals obtained in step P ) to obtain crystals containing lycopene in an amount of at least 40 weight-%, based on the total weight of the crystals;

whereby preferably step P ) is repeated at least once and more preferably at least twice. The steps are preferably carried out in the given order.

The extraction of the tomato pomace or the tomato peels with the organic solvent, i.e. steps a1 ) to hi ) may also be carried out several times, preferably from 1 to 3 times. The crystallization, i.e. step i 1 ), may also be carried out several times, preferably from 2 to 3 times in total, whereby different anti-solvents may be used.

If the crystallization step P ) is carried out 3 times in total, crystals containing lycopene in an amount of at least 60 weight-%, based on the total weight of the crystals, can be obtained.

In an embodiment of the preferred process of the present invention only part of the oily extract obtained in step g1 ) is treated according to steps P ) and j 1 ) to obtain crystals. The corresponding process comprises an additional step k1 ) carried out after step j1 ): k1 ) mixing the oily extract containing lycopene in an amount of at least 1 .5 weight-%, based on the total weight of the oily extract, as obtained in step g1 ) with the crystals containing lycopene in an amount of at least 40 weight- %, based on the total weight of the crystals, as obtained in step j 1 ) to obtain an oily extract containing lycopene in an amount of at least 5 weight-%, based on the total weight of the oily extract.

In a preferred embodiment of the present invention the process consists only of the steps a1 ) to j 1 ), whereby it is not excluded that single steps of these steps may be performed several times. In another preferred embodiment of the present invention the process consists only of the steps a1 ) to k1 ), whereby it is not excluded that single steps of these steps may be performed several times. That means that no other steps than a1 ) to j 1 ) or a1 ) to k1 ) are carried out such as e.g. grinding of the starting material which is necessary according to some processes of the prior art.

Fig. 1 is an illustration of the process of the present invention.

The oily extract which is obtained after having performed steps a) to g) or steps a1 ) to g1 ) of the processes of the present invention preferably contains lycopene in an amount in the range of from 2.0 to 2.5 weight-%, based on the total weight of the oily extract. This oily extract is also called“first oleoresin” (“1 st OR”) since it still contains beside lycopene other valuable and original biologically active compounds from tomato such as phytosterols, phytoenes, tocopherols, b-carotene etc.

The single steps are now described in detail below. Step a)/a1 )

Tomato pomace comprising tomato peels and tomato seeds is provided. It is obtained as by-product in the tomato processing industry such as the manufacture of tomato sauces, tomato pastes, tomato purees, tomato ketchups, tomato juices, and concentrates thereof. It contains mainly tomato peels and tomato seeds and minor amounts of stem and leaf fibers beside some residual pulp.

Alternatively, tomato peels could also be used as starting material instead of tomato pomace. Tomato peels are obtained as by-products from the whole peeled tomato canning industry or can be obtained from pomace by separation of seeds.

Step b)/b1 )

Water is added to the tomato pomace or the tomato peels, preferably in an amount ranging from 1 to 10 times the volume of the tomato pomace or tomato peels, more preferably in an amount ranging from 1 to 5 times the volume of the tomato pomace or tomato peels, even more preferably in an amount ranging from 1 to 3 times the volume of the tomato pomace or tomato peels, most preferably from 1.2 to 2.1 times the volume of the tomato pomace or tomato peels, whereby an aqueous suspension is obtained. Preferably the amount of water added is minimized to obtain a suspension still allowing efficient mixing and mass transfer by agitation. The amount of water is also dependent on the moisture of the tomato pomace or tomato peels: If the tomato pomace or tomato peels have a high moisture content, less water is needed. It was found that preferably the added water amount is minimized to avoid losses of the ethyl acetate due to its miscibility with water and thereby reducing the volume of the solvent.

Step cl/d

To the aqueous suspension obtained in step b) and step b1 ), respectively, is added at least one enzyme to obtain an enzyme containing suspension.

Surprisingly it was found, that the enzyme is already efficient in a concentration of 0.03 weight-%, based on the weight of the enzyme containing suspension. This is much less enzyme than known in the prior art. Thus, the total concentration of the enzyme used is preferably in the range of from 0.005 to 1 weight-%, more preferably in the range of from 0.007 to 0.5 weight-%, most preferably in the range of from 0.01 to 0.1 weight-%, based on the weight of the enzyme containing suspension. The enzyme can be a single enzyme or a mixture of several enzymes.

After reaction of the enzyme or enzyme mixture with the aqueous suspension an enzyme-treated reaction mixture results.

At minimum it is a pectinase (polygalacturonase). Additionally, a pectine esterase may also be used.

Preferably a hemicellulase and/or a cellulase (1 ,4-6-glucanase) may be used additionally; more preferably a hemicellulase (a-L-arabinofuranosidase) is used additionally. Furthermore, a xylanase and/or a galactanase may also be used additionally.

Commercially available examples of enzymes are often mixtures of enzymes such as Rapidase Power (DSM Food Specialties, NL), Peclyve LI (Lyven SA, FR), Rapidase TF (DSM Food Specialties, NL), Rapidase Fiber (DSM Food Specialties, NL) and Maxoliva HCl.

Rapidase Power is a mixture of a pectinase and a hemicellulase. Peclyve LI contains enzyme activities of pectinase, pectine esterase, hemicellulase and cellulase. Rapidase TF is a mixture of pectinase and cellulase activities. Rapidase Fiber is a mixture of a pectinase, a hemicellulase and a cellulase activities. Maxoliva HCl is a mixture of a pectinase and a cellulase activities. An example of a commercially available pectinase is Rapidase Press L.

All enzymes mentioned above may be used in the processes of the present invention. Step d)/ step d1 )

An organic solvent is added to the enzyme-treated reaction mixture obtained in step c)/d ) to obtain a mixture, wherein the organic solvent is preferably either ethyl acetate or isobutyl acetate or hexane or heptane or dichloromethane or any mixture thereof, more preferably the organic solvent is ethyl acetate. Ethyl acetate is preferred over hexane due to a higher yield. Ethyl acetate is preferred over isobutyl acetate for large-scale industrial application due to a cost advantage and regulatory constraints since ethyl acetate is already registered for food-grade lycopene extraction from tomato products.

The organic solvent is used in an amount ranging from 1 to 3 times the weight of the tomato pomace or the tomato peels, preferably ranging from 1.2 to 1 .6 times the weight of the tomato pomace or the tomato peels. This is also significantly lower than in the state of the art.

Step e)/e1 )

The solids are separated from the mixture obtained in step d)/d1 ) to obtain a biphasic mixture with an aqueous phase and an organic solvent phase. The lycopene is in the organic solvent phase.

The solid liquid separation is advantageously performed by a decanter centrifuge.

Step f)/step f1 )

The aqueous phase and the organic solvent phase are separated, preferably by centrifugation, or by settling and decantation, and more preferably by a disk stack centrifugation, to obtain the organic solvent phase and the aqueous phase.

Step g)/step g1 )

The organic solvent phase containing lycopene is recovered, preferably by decantation, and the organic solvent is evaporated to obtain an oily extract containing lycopene in an amount of at least 1 .5 weight-%, based on the total weight of the residual oily extract. Preferably the amount of lycopene in the oily extract is ranging from 1 .5 to 5 weight-%, more preferably from 2.0 to 2.5 weight-%, based on the total weight of the oily extract. When isobutyl acetate is used as solvent the amount of lycopene in the oily extract is around 2.7 weight-%, based on the total weight of the oily extract. When hexane is used as solvent the amount of lycopene in the oily extract is around 5 weight-%, based on the total weight of the oily extract.

Step h)/step h 1 )

The organic solvent obtained in step g)/g1 ) may be re-used again in step d)/d1 ); i.e. the organic solvent may be recycled into step d)/d1 ). Preferably this step is carried out to increase the sustainability of the process.

Step i)/step P )

The oily extract obtained in step g)/g1 ) is crystallized with an anti-solvent and then the resulting crystals are separated from the mother liquor by centrifugation or filtration, preferably by centrifugation, to obtain crystals containing lycopene in an amount of at least 40 weight-%, preferably in an amount of at least 50 weight-%, most preferably in an amount of at least 60 weight-%, based on the total weight of the crystals.

Preferably the anti-solvent is an alcohol (preferably ethanol or isopropanol or methanol) or a ketone (acetone) or any mixture thereof, whereby one or more of these anti-solvents may be mixed with themselves or with water and said mixture used.“Anti-solvent” in the context of the present invention means a solvent with low solubility for lycopene, i.e. less than 0,1 g/L at 20°C. Preferred mixtures of the anti-solvents are acetone-alcohol, alcohol-water and ketone-water. More preferred mixtures of the anti-solvents are acetone-ethanol, ethanol-water and acetone-water.

Preferred examples of the alcohol are ethanol, isopropanol and methanol, whereby ethanol is preferred.

A preferred example of the ketone is acetone. More preferred anti-solvents are ethanol, acetone-ethanol, ethanol-water and acetone-water; whereby ethanol is most preferred.

When the anti-solvent is added to the extract containing lycopene in an amount of at least 1 .5 weight-% as obtained in step g) and step g1 ), respectively, based on the total weight of the extract, lycopene crystallizes. The crystals are then collected by centrifugation or by filtration whereby crystals containing lycopene in a purity of at least 40 weight-%, preferably in a purity of at least 50 weight-%, based on the total weight of the crystals, are obtained.

More preferably the amount of lycopene in the extract is > 55 weight-%, most preferably > 60 weight-%, based on the total weight of the extract.

As already stated above, preferably step i) and step P ), respectively, is repeated at least once, more preferably at least twice.

Step i )/ j 1 )

The drying of the crystals is preferably performed under oxygen-limiting conditions, i.e. either under vacuum or N 2 atmosphere, to obtain concentrated crystals containing lycopene in an amount of at least 40 weight-%, based on the total weight of the crystals.

The invention is now further illustrated in the following non-limiting examples.

Examples

The following abbreviations are used :

LP lycopene

MC moisture content

min minute(s)

rpm rotations per minute

sec second (s) Wt.% weight-%

Example 1 : Effect of enzymatic treatment of tomato pomace on the lycopene extraction

The effect of enzymes and homogenization was tested with a mixture of 8 g of tomato pomace in 30 g of deionized water. This mixture was homogenized or not by a Polytron PT 3100 homogenizer (2 * 30 sec, 15000 rpm). Different commercially available enzymes such as Rapidase TF (“TF”; from DSM food specialties; since summer 2017 replaced by Rapidase Fiber) or Maxoliva HCl were then incubated for 2 h under strong agitation at room temperature with the resulting tomato pomace slurry. For comparison, a tomato pomace sample was directly extracted with 25 g of ethyl acetate without pre-incubation in water. The aqueous samples, treated or not by different enzymes, were extracted with 15 g of ethyl acetate by stirring for 2 hours at room temperature. After 10 min centrifugation at 4500 g, the upper organic phase of ethyl acetate (-13 ml) was recovered and analyzed for lycopene by HPLC. The results are shown in Table 1 .

By homogenization in either ethyl acetate or water, the yield of extracted lycopene based on the initial lycopene concentration in 8 g of tomato pomace increased by 6 and 15%, respectively. Overnight soaking and softening of tomato peels in water was beneficial as seen by an approximately 20% higher lycopene yield in the extract compared to the direct solvent extraction without adding water. Additionally, a 17% yield gain was obtained by enzymatic pretreatment using Rapidase TF. A dosage of 0.05% Rapidase TF was as good as 0.5%, and 2 h of enzyme treatment were as good as 18 h. No additional benefit was seen by another enzyme, Maxoliva HCl.

2 nd Extraction cycle: The tomato pomace residues of the 1 st extraction cycle were extracted a second time, again for 2 h with 15 g of ethyl acetate. This increased the overall lycopene yield by 4-10%. Best overall lycopene extraction yield of 98% after two extraction cycles was reached by the enzymatic pretreatment with 0.05% of Rapidase TF. The directly ethyl acetate-extracted samples (without adding water) showed an increased yield in the second extraction cycle, indicating that much more solvent is required when water is omitted. It showed that an enzyme mixture containing activities of pectinase

(polygalacturonase), hemicellulases (arabinofuranosidase), cellulase, such as Rapidase TF (or its successor Rapidase Fiber), is beneficial for the extraction of lycopene from tomato pomace.

Table 1 : Enzymatic treatment of tomato pomace

Example 2: Extraction after enzymatic treatment using Rapidase Fiber

500 g of tomato pomace with a lycopene concentration of 0,21 g/kg and a moisture content of 64% were mixed with 800 g of water and 0.4 g of the commercially available enzyme Rapidase Fiber (a mixture of pectinase, cellulase and hemicellulase). The mixture was vigorously agitated at 500 rpm for 5 hours at room temperature under a nitrogen atmosphere. For extraction, 700 g of ethyl acetate were added, and the agitation continued for 2 hours under a nitrogen atmosphere. Then the mixture was centrifuged for 5 min at 4000 g and the solvent phase recovered by decantation of the supernatant, followed by evaporation at 40 °C under reduced pressure of 10 mbar until a constant amount had been achieved. An oleoresin of 3.3 g containing 2.3 wt.% of lycopene at an isomeric ratio of 95% all-E was obtained, corresponding to a lycopene yield of 72%. Example 3: Extraction after enzymatic treatment using Rapidase Power

For comparison, Rapidase Power was used as enzyme. Otherwise, parameters were the same as in example 2. As a result, an oleoresin of 3.1 g containing 2.5 wt.% of lycopene with an isomeric ratio of 95% all-E was obtained. Example 4: Extraction after enzymatic treatment using Rapidase Press

For comparison, Rapidase Press was used as enzyme. Otherwise, parameters were the same as in the example 2. 3.3 g oleoresin containing 2.1 wt.% of lycopene with an isomeric ratio of 96% all-E were obtained. Example 5: Extraction after enzymatic treatment using Peclyve LI

For comparison, 1 .0 g Peclyve LI was used as enzyme. Otherwise, parameters were the same as in example 2. After extraction and evaporation, an oleoresin of 3.4 g containing 2.3 wt.% of lycopene was obtained. Comparative example 6: Extraction after homogenization

For comparison, a homogenization step of the pomace-water mixture was included before enzyme addition. The homogenization was done using a Polytron PT 3100 applying two high -shear force cycles of 30 sec at 25000 rpm, separated by a pause of 30 sec to avoid heating. All other parameters were the same as in example 2. After evaporation to weight constancy, an oleoresin of 13.2 g containing 0.28 wt.% of lycopene was obtained. Example 7: Extraction with isobutyl acetate

For comparison, isobutyl acetate was used as extraction solvent. Otherwise, parameters were the same as in example 2. After extraction and evaporation, an oleoresin of 2.4 g containing 2.7 wt.% of lycopene at an isomeric ratio of 95% all-E was obtained. Besides a slightly higher selectivity for lycopene, isobutyl acetate has the advantage of having a lower water miscibility compared to ethyl acetate, thus reducing solvent losses during extraction.

Example 8: Extraction with hexane

For comparison, hexane was used as extraction solvent. Otherwise, parameters were the same as in example 2. An oleoresin of 1 .0 g containing 5.3 wt.% of lycopene at 96% all-E was obtained. In contrast to ethyl acetate, hexane is not miscible with water which avoids solvent losses during extraction. It also has a higher selectivity for lycopene, co-extracting less polar impurities from tomato pomace due to its non-polar character.

Example 9: Comparison of anti-solvents ethanol, isopropanol and acetone after one crystallization cycle

To three aliquots of each 3.3 g oleoresin containing 2.3 wt.% lycopene, obtained as described in example 2, were added 30 g of each ethanol, isopropanol, and acetone, followed by 10 min agitation of the suspension. The precipitated crystals were collected by centrifugation (5 min at 4000 g), and the supernatant containing beta carotene removed by decantation. After overnight vacuum drying at 40°C and 20 mbar, the precipitated crystals had a lycopene purity of 22.6%, 19.5% and 26.2%, after ethanol, isopropanol, and acetone treatment, respectively. The results are summarized in Table 2. Regarding the yield of lycopene, ethanol was the most suitable anti-solvent. Acetone had the lowest lycopene yield due to losses in the mother liquor by a higher solubility. Table 2

Example 10: Three crystallization cycles of oleoresin with ethanol

An oleoresin of 3.3 g containing 2.3 wt.% of lycopene, obtained as in example 2, was crystallized in three consecutive cycles. Each crystallization cycle was done by adding 30 g of ethanol before 10 min of mild agitation of the alcohol-oleoresin suspension at room temperature, followed by centrifugation at 4000 g for 5 min and decantation of the supernatant. Beta-carotene was removed in the supernatant mother liquors of the first two cycles due to its solubility in ethanol. After the third crystallization and drying in at 40° C under reduced pressure of 20 mbar, 72 mg of lycopene crystals with a purity of 61 .6 wt.% and an isomeric ratio of 97% all-E were obtained. Example 1 1 : Three crystallization cycles with different anti-solvents

3.3 g of an oleoresin containing 2.3 wt.% of lycopene was obtained as described in example 2. The oleoresin was crystallized in three consecutive cycles, first by 38 g of ethanol, then by a mixture of 28 g of ethanol plus 19 g of acetone, and last by a mixture of 27 g of isopropanol plus 16 g of acetone. After each crystallization cycle of 20 min agitation on a magnetic stirrer, the crystal suspension was centrifuged for 5 min at 4000 g and the supernatant mother liquor removed by decantation. After vacuum drying at 40°C and 20 mbar of the 3 rd crystalline pellet, a lycopene purity of 69 wt.% was obtained (Table 3). Table 3

Example 12: Enrichment of oleoresin by mixing with purified lycopene crystals From 19.3 g of an oleoresin mixture containing 2.3 wt.% of lycopene, obtained from several extraction batches according to the example 2, 12.2 g were washed twice with each 100 g of ethanol, followed by centrifugation at 4000 g for 5 min and discarding the mother liquor by decantation of the supernatant. After drying at 40°C under a reduced pressure of 20 mbar, the resulting 0.58 g lycopene crystals had a purity of 41 .2 wt.% with an enantiomeric excess of 98% all-E. These crystals were mixed with 7.1 g of the remaining unwashed oleoresin to give 7.65 g oleoresin at a lycopene purity of 5.1 wt.% containing 96% all-E.

It is obvious to a person skilled in the art, that an oleoresin containing at least 5 wt.% lycopene could also be achieved by mixing said unwashed oleoresin with lycopene crystals of a purity of more than 60 wt.%, which can be obtained as described in examples 10 and/or 1 1 .