METHOD FOR PRODUCE AN EXTRACT MADE FROM SUMAC CONTAINING GALLIC ACID, AQUEOUS CONCENTRATE MADE THEREIN THEREIN, AND FOOD PRODUCTS AND FOOD SUPPLEMENTS CONTAINING THE AQUEOUS CONCENTRATE

Description

[0001] The present invention relates to a process for producing an extract containing gallic acid, in particular in high concentrations. The invention further relates to an aqueous concentrate containing gallic acid. The invention also relates to foodstuffs and food supplements containing the aqueous concentrate according to the invention. Gallic acid (3,4,5-trihydroxybenzoic acid) is the acid component of gallotannins, which are hydrolyzable tannins. They are found, for example, in oak bark and gallnuts. Gallic acid is used in the production of antioxidants, sunscreens, and dyes. Furthermore, it has been postulated that gallic acid, due to its hypoglycemic properties, helps prevent adverse health effects in obese individuals who consume foods rich in gallic acid. The consumption of gallic acid is said to provide demonstrable DNA protection.reduced oxidation of DNA bases and reduced inflammatory parameters (see also T. Setayesh et al. "Gallic acid, a common dietary phenolic protects against high fat diet induced DNA damage" in European Journal of Nutrition, Vol. 58, pages 2315 to 26, 2019).

[0002] According to EP 1 942 919 B1, a composition containing a polyphenol extract from grapes, which may contain 400 to 1500 ppm of gallic acid, is said to be suitable for the treatment of metabolic syndrome or prehypertension.

[0003] According to EP 2 095 718 B1, a tea beverage derived from a tea extract in which the weight ratio of gallic acid to non-polymeric catechins may not exceed 0.3 is said to be characterized by reduced bitterness and a reduced sour taste.

[0004] EP 2 143 344 B1 describes a beverage composition containing 0.5 to 25.0 wt.% non-polymeric catechins, a carbohydrate, and a hydroxycarboxylic acid. In these compositions, the gallic acid content must be less than 0.6 wt.%.

[0005] B. Kar et al., in their article "Microbial production of gallic acid by modified solid-state fermentation," Journal of Industrial Microbiology & Biotechnology, 1999, 23, pages 173-177, describe the bioconversion of tannin to gallic acid using the enzyme tannase. Diethyl ether was used as the solvent for the extraction of gallic acid from the fermented biomass.

[0006] H. Purrat et al. describe in the publication "Microbial production of gallic acid form Rhus Coriaria L.", Biotechnology Letters Vol 9, No 10, 1987, pages 731-734, the production of gallic acid-containing extracts from sumac leaves, whereby these sumac leaves are first mixed with boiling water and then, without prior filtration, in the presence of A. niger , a tannase-producing strain. Crystalline gallic acid was obtained from the filtered supernatant.

[0007] According to the publication " Tannic acid", prepared at the 39th Joint Expert Committee on Food Additives (JECFA), 1992, and published in FNP Add 1 (1992), tannic acid, which is highly soluble in water and ethanol, can be obtained by solvent extraction from, for example, sumac plants and hydrolyzed to gallic acid.

[0008] JP 4630295 B2 discloses a process for producing a tea extract in which tea raw materials are first treated with tannase in water. Subsequently, extraction is carried out after adding an aqueous ethanol solution. Extraction in the presence of ethanol is said to increase the yield of catechins.

[0009] EP 2 022 346 A1 describes the treatment of green tea extracts with high catechin content with tannase and their subsequent spray drying. The resulting powder was extracted with a solvent mixture of ethanol and water (85:15) and then purified with activated carbon.

[0010] WO 00 / 150 044 A1 discloses a pharmaceutical composition containing an effective amount of tannin, gallic acid and / or ellagic acid.

[0011] EP 2 606 902 A1 describes a process for producing an extract from Rhus copallina described in which crushed leaves of Rhus copallina L.extracted with a mixture of water and ethanol. Extraction can be carried out, for example, by maceration or percolation.

[0012] In the article "Tannase enhances the anti-inflammatory effect of grape pomace in Caco-2 cells treated with IL-1β," Journal of Functional Foods 29 (2017), pages 69-76, I. Martins et al. describe the extraction of grape seed pomace with an aqueous tannase solution. After adding methanol, sonication, centrifugation, and freeze-drying the supernatant, a solid containing small amounts of gallic acid was obtained.

[0013] E. Bursal et al. report in "Evaluation of reducing power and radical scavenging activities of water and ethanol extracts from suma (Rhus coriaria L.)", Food Research International 44 (2011), pages 2217-2221, that extraction of sumac plants with ethanol does not lead to improved extraction of phenolic compounds compared to extraction with water.

[0014] Gallic acid has so far often been extracted using aqueous extraction methods. However, these processes typically result in low yields of gallic acid and are material-, equipment-, and cost-intensive.

[0015] The present invention was therefore based on the object of making available a process for the recovery of gallic acid which is not afflicted with the disadvantages of the prior art and which, in particular, makes gallic acid available reliably in good yields in an efficient manner.

[0016] Accordingly, a process for producing an extract containing gallic acid was found (also called the first embodiment of the process according to the invention), comprising the steps a) Providing of, in particular crushed and / or dried, plants or plant components containing tannins, in particular tannic acid, wherein the plant provided comprises or represents a sumac plant and wherein the plant components comprise or represent leaves, wood, bark, seeds, roots and / or fruits of sumac plants, b) Providing of the enzyme tannase (IUB 3.1.1.20), c) Providing of ethanol, d) if appropriate crushing or further crushing of the plants or plant components according to a) and e) extractive treatment of the plants or plant components obtained according to step a) and / or d), in particular crushed, with water in the presence of the enzyme tannase (IUB 3.1.1.20) to obtain a product mixture containing gallic acid, f) separating the, in particular comminuted, plants or plant components from the product mixture obtained according to step e), in particular after step e), and g) evaporatively concentrating the product mixture obtained according to step e) or f) containing gallic acid, in particular after step e) or f) and / or before step h), and h) treating the product mixture according to step e) or f) with ethanol and treating the product mixture according to step e) or f) or g) with heat and i) filtering the treated product mixture according to step h) and j) removing the ethanol added in step h) from the treated product mixture according to step h) or the filtered product mixture according to step i), k) evaporatively concentrating the aqueous extract obtained according to step j) containing gallic acid to obtain an aqueous concentrate, . wherein in step h) ethanol is added in an amount in the range of 20 to 65 percent by weight, based on the total weight of the ethanol and the water or the aqueous system.

[0017] The plants or plant parts used, especially crushed and / or dried, are leaves, wood, bark, fruits, seeds and / or roots, preferably the fruits, of sumac plants ( Rhubarb ), especially on the leaves, bark and fruits of sumac ( Rhus coriaria ), especially the fruits.

[0018] Sumac plants ( Rhubarb ) are used, with particular emphasis on sumac ( Rhus coriaria ). Preferred plant components of sumac plants, especially spice sumac ( Rhus coriaria ), include leaves, bark and / or fruits, with the fruits being particularly preferred.

[0019] In a preferred embodiment, the process according to the invention is also characterized in that the extractive treatment according to step e) extends over a maximum period of 4 hours, in particular over a maximum period of 3 hours. With the process according to the invention according to the first embodiment, an extract with a high concentration of gallic acid can be obtained within relatively short extraction times.

[0020] The method according to the invention according to the first embodiment further comprises (step f)) the separation of the, in particular comminuted, plants or plant components from the product mixture obtained according to step e), in particular following step e), preferably with the aid of a sieve.

[0021] In addition, the process according to the invention according to the first embodiment also comprises (step g)) the evaporative concentration of the product mixture obtained according to step e) or f) containing gallic acid, in particular after step e) or f) and / or before step h).

[0022] The process according to the invention according to the first embodiment further comprises (step h)) treating the product mixture according to step e) or f) with ethanol and treating the product mixture according to step e) or f) with heat. Treatment with ethanol and additional treatment with heat regularly result in deactivation of the enzyme tannase. This is achieved in particular by treating the product mixture with ethanol in step h) at temperatures in the range from 40 to 80°C or above 45 to 80°C, preferably 40 to 75°C or 48 to 75°C, and particularly preferably 50 to 70°C.To further optimize process step h), it is proposed that ethanol be added in this step in an amount ranging from 20 to 65 percent by weight, preferably from 25 to 60 percent by weight, and in particular from 40 to 60 percent by weight, based in each case on the total weight of the ethanol and the water or the aqueous system. Step h), in particular the treatment with ethanol, regularly succeeds in deactivating the enzyme and denaturing and precipitating phytoproteins and / or polysaccharides.

[0023] Steps f) and g) follow one another. In a particularly preferred embodiment, process steps f), g), h) follow process step e) in this order.

[0024] In the process according to the invention according to the first embodiment, the treated product mixture according to step h) is filtered, for example, with a filter having a mesh size in the range of 0.10 to 1.0 µm, preferably in the range of 0.25 µm to 1.0 µm, and particularly preferably in the range of 0.35 µm to 0.55 µm. In this way, a clear extract is generally obtained.

[0025] The ethanol added in step h) is then removed again from the treated product mixture according to step h) or the filtered product mixture according to step i) (step j). The extractive treatment according to step e) is preferably carried out at temperatures in the range of 20 to 45 °C or 30 to 43 °C, with temperatures in the range of 35 to 40 °C, in particular in the range of 36 to 38 °C, being particularly preferred.

[0026] The object underlying the invention is further achieved by a process for producing an extract containing gallic acid (also called a second embodiment of the process according to the invention), comprising the steps 1) Provision of, in particular crushed and / or dried, plants or plant components containing tannins, in particular tannic acid, wherein the plant provided comprises or represents a sumac plant and wherein the plant components comprise or represent leaves, wood, bark, seeds, roots and / or fruits of sumac plants, 2) Provision of the enzyme tannase (IUB 3.1.1.20), 3) Provision of ethanol, 4) if necessary crushing orfurther comminution of the plants or plant components according to step 1), 5) extractive treatment of the, in particular dried and / or comminuted, plants or plant components according to step 1) and / or 4) with a mixture containing the ethanol and water to obtain a product mixture containing polyphenols, 6) separating the, in particular comminuted, plants or plant components from the product mixture according to step 5) to obtain a liquid extract containing the polyphenols, in particular with the aid of a sieve, 7) removing the ethanol from the liquid extract according to step 6) to obtain an aqueous extract containing the polyphenols, 8) treating the aqueous extract according to step 7) with the enzyme tannase (IUB 3.1.1.20) to obtain an aqueous system containing gallic acid, 9) evaporative concentration of the aqueous system containing gallic acid according to step 8) to obtain an aqueous concentrate, . wherein in step 5) ethanol is added in an amount ranging from 60 to 90 percent by weight, based on the total weight of ethanol and water.

[0027] The object underlying the invention is also achieved particularly well with the method according to the second embodiment variant by carrying out the extractive treatment according to step 5) at temperatures in the range from 50 to 70 °C, in particular in the range from 55 to 65 °C.

[0028] In a preferred embodiment, the second embodiment of the process according to the invention is also characterized in that in step 5) ethanol is added in an amount in the range of 70 to 85 percent by weight, based on the total weight of ethanol and water.

[0029] In the second embodiment of the process according to the invention, the treatment of the aqueous extract according to step 8) with the enzyme tannase is preferably carried out at temperatures in the range from 20 to 45 °C, preferably 30 to 43 °C, particularly preferably 35 to 40 °C and in particular in the range from 36 to 38 °C. Surprisingly, it has been shown that a particularly efficient process can also be achieved by immobilizing the, in particular ground, preferably comminuted, plants or plant components in step e) according to the first embodiment or step 5) according to the second embodiment, in particular immobilizing them in a portafilter.

[0030] The extractive treatment according to step e) in the first embodiment or step 5) in the second embodiment preferably comprises or represents a percolation process.

[0031] Particularly high yields or concentrations of gallic acid can also be achieved with the processes according to the invention by setting the amount of tannase in step e) according to the first embodiment or step 8) according to the second embodiment in the range from 0.1 U / g to 100.0 U / g, preferably in the range from 0.2 U / g to 50.0 U / g, based on the amount of plants or plant components. According to the invention, the aqueous extract containing gallic acid obtained after step j) according to the first embodiment or the aqueous system containing gallic acid according to step 8) according to the second embodiment is evaporatively concentrated to obtain an aqueous concentrate. This is preferably a so-called spissum extract. This aqueous concentrate orThis spissum extract, obtained from sumac plants, particularly preferably sumac, or components thereof, in particular the fruits, especially obtained according to the first embodiment, has in particular a Brix value in the range of 1° to 100° Brix, preferably in the range of 10° to 70° Brix, and particularly preferably in the range of 20° to 50° Brix. In the concentration step, concentrates with Brix values ​​in the range of 20° to 40° Brix, in particular in the range of 25° to 35° Brix, are particularly preferably sought or obtained. The determination of Brix degrees is familiar to the person skilled in the art. A liquid has a Brix value of 1° if it has the same density as a solution of 1 g of sucrose in 100 g of sucrose / water solution, and a Brix value of 10° if its density is that of a solution of 10 g of sucrose in 100 g of sucrose / water solution.Thus, the indication in degrees Brix means that the density of the measured liquid corresponds to the density of a solution of sucrose in water, which contains as many grams of sucrose per 100 g of solution as the degree indication indicates.

[0032] The object underlying the invention is further achieved by an aqueous concentrate according to claim 18, containing gallic acid, obtained according to the first or second embodiment, wherein the amount of dry matter used for this aqueous concentrate is in the range of 5 to 80 percent by weight, preferably in the range of 10 to 50 percent by weight, and particularly preferably in the range of 15 to 40 percent by weight, in each case based on the total weight of the aqueous concentrate. These aqueous concentrates are particularly suitable for the production of foodstuffs and food supplements, especially those in the form of beverages.

[0033] For the purposes of the invention, dry matter is understood to mean the dry matter obtained by removing all aqueous and non-aqueous solvents from the extracts obtainable by the processes according to the invention.

[0034] The aqueous concentrates according to the invention are obtained either by the process according to the invention according to the first embodiment or by the process according to the invention according to the second embodiment, with preference being given to those aqueous concentrates which are accessible by the process according to the invention according to the first embodiment.

[0035] The aqueous concentrates according to the invention, obtained from sumac plants, particularly preferably spice sumac, or components thereof, in particular the fruits, in particular obtained according to the first embodiment, have a pH in the range from 1.5 to 5.5, preferably in the range from 1.75 to 4.5 and particularly preferably in the range from 2.0 to 4.0, or are adjusted to a pH in the range from 1.5 to 5.5, preferably in the range from 1.75 to 4.5 and particularly preferably in the range from 2.0 to 4.0.

[0036] In the aqueous concentrates according to the invention, obtained from sumac plants, particularly preferably spice sumac, or components thereof, in particular the fruits, in particular obtained according to the first embodiment, the amount of gallic acid is at least 10 g / kg dry matter, preferably at least 50 g / kg dry matter and particularly preferably at least 75 g / kg dry matter, and / or gallic acid is present in an amount in the range from 10 to 250 g / kg dry matter, preferably in the range from 50 to 200 g / kg dry matter and particularly preferably in the range from 75 to 175 g / kg dry matter, in each case based on the total weight of the aqueous concentrate.

[0037] The aqueous concentrates according to the invention, obtained from sumac plants, preferably spice sumac, or components thereof, in particular the fruits, in particular obtained according to the first embodiment, have a relative density [20 / 20] in the range from 1.001 to 1.4000, preferably in the range from 1.010 to 1.2500. The relative density [20 / 20] is the quotient of the density of the sample examined (measured at 20°C) and the density of water at 20°C. The measurement is carried out in particular by means of a U-bendometer according to Section 35 LMBG 36.0 3a (German Food and Consumer Goods Act in the version applicable on the date of application) (determination of the relative density d 20 / 20 of wort and beer (U-bendometer method).Particularly suitable aqueous concentrates are characterized by a total phenol content in the range of 5 to 350 g GAE / kg, preferably in the range of 50 to 300 g GAE / kg and particularly preferably in the range of 75 to 250 g GAE / kg and in particular in the range of 125 to 200 g GAE / kg, in each case based on the dry mass of the extract.

[0038] The total phenol content can be determined using the method according to DIN ISO 14502-1:2007-11 (Determination of characteristic substances of green and black tea - Part 1: Total polyphenol content in tea - Colorimetric method using Folin-Ciocalteu reagent).

[0039] Furthermore, the object underlying the invention is achieved by a food, for example a beverage, as well as by a food supplement, containing or formed from the aqueous concentrate according to the invention.

[0040] The present invention is accompanied by the surprising finding that when using the extraction methods according to the invention according to the first embodiment as well as according to the second embodiment, but in particular according to the first embodiment, gallic acid can be extracted in high yields effectively and cost-effectively from a variety of plant materials or components thereof, whereby aqueous concentrates with a very high gallic acid concentration are accessible.It was surprisingly found that the aqueous concentrates according to the invention, obtained from sumac plants, particularly preferably sumac, or components thereof, in particular the fruits, especially obtained according to the first embodiment, have a Trolox-equivalent antioxidant capacity in the range of 500 to 6000 µmol / g, preferably in the range of 1000 to 5000 µmol / g, and particularly preferably from 2000 to 4000 µmol / g, in each case based on the dry mass of the extract. The Trolox-equivalent antioxidant capacity can conveniently be determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. This determination method is familiar to the person skilled in the art and is described, for example, by O. Sharma and TN Bhat in "DPPH antioxidant assay revisited", Food Chemistry 113(4):1202-1205, April 2009, and by A. Karioti et al. in "Composition and antioxidant activity of the essential oils of Xylopia aethiopica (Dun) A. Rich.(Annonaceae) leaves, stem bark, root bark, and fresh and dried fruits, growing in Ghana", J. Agric. Food Chem. 29;52(26):8094-8, December 2004. For example, in this method, 10 mg of the stable radical DPPH can be dissolved in 100 ml of methanol and, after mixing with the respective sample extract or the standard (Trolox), incubated for 30 min at room temperature. The absorbance can then be determined photometrically at 517 nm. The antioxidant potential of the samples can then be determined from a linear relationship between absorbance and the standard concentrations. The results can be calculated as Trolox equivalents or as micromoles of Trolox / g sample and related to the dry mass. Using the described method, an absorbance difference is determined, from which the antioxidant capacity of the substance under investigation can be determined by comparing it with the reduction in absorbance caused by Trolox at different concentrations.

[0041] The aqueous concentrates according to the invention can be used directly for the production of foodstuffs, in particular beverages, and food supplements. The features of the invention disclosed in the above description and in the claims can be essential for the realization of the invention in its various embodiments, both individually and in any combination.

Claims

1. Method for producing an extract containing gallic acid, comprising the steps a) providing, in particular dried and / or, in particular and, comminuted, plants or plant components containing tannins, in particular tannic acid, wherein the provided plant comprises or is a sumac plant and wherein the plant components comprise or are leaves, wood, bark, seeds, roots and / or fruits of sumac plants, b) providing the enzyme tannase, c) providing ethanol, d) optionally comminuting or further comminuting, respectively, of the plants or plant components according to step a), e) extracting the, in particular comminuted, plants or plant components obtained according to step a) and / or d), in particular or, with water in the presence of the enzyme tannase to obtain a product mixture containing gallic acid, f) separating the, in particular comminuted, plants or plant components from the product mixture obtained according to step e), in particular following step e), and g) evaporative concentrating of the product mixture containing gallic acid obtained according to step e) or f), in particular following step e) or f) and / or before step h), and h) treating the product mixture according to step e) or f) with ethanol and treating the product mixture according to step e) or f) or g) with heat for the deactivation of the enzyme tannase and for the denaturing and precipitation of proteins and / or polysaccharides, and i) filtering the treated product mixture according to step h), and j) removing the ethanol added in step h) from the treated product mixture according to step h) or the filtered product mixture according to step i), k) evaporative concentrating of the aqueous extract containing gallic acid obtained according to step j) to obtain an aqueous concentrate, wherein ethanol is added in step h) in an amount in the range from 20 to 65 percent by weight, based on the total weight of the ethanol and the water or the aqueous system, respectively.

2. Method according to claim 1, characterized in that the extractive treatment according to step e) is carried out at temperatures in the range from 20 to 45°C.

3. Method according to one of the preceding claims, characterized in that the treatment of the product mixture with ethanol according to step h) is carried out at temperatures in the range from 40 to 75°C.

4. Method according to one of the preceding claims, characterized in that the ethanol is added in step h) in an amount in the range from 40 to 60 percent by weight, based on the total weight of the ethanol and the water or the aqueous system, respectively.

5. Method according to one of the preceding claims, characterized in that the extractive treatment according to step e) extends over a period of a maximum of 4 hours, in particular a period of a maximum of 3 hours.

6. Method according to one of claims 1 to 5, characterized in that the filtration according to step i) is carried out with a filter having a mesh width in the range from 0.25 µm to 1.0 µm, in particular in the range from 0.35 µm to 0.55 µm.

7. Method for producing an extract containing gallic acid, comprising the steps 1) providing, in particular comminuted and / or, in particular and, dried, plants or plant components containing tannins, in particular tannic acid, wherein the provided plant comprises or is a sumac plant and wherein the plant components comprise or are leaves, wood, bark, seeds, roots and / or fruits of sumac plants, 2) providing the enzyme tannase, 3) providing ethanol, 4) optionally comminuting or further comminuting, respectively, the plants or plant components according to step 1), 5) extractive treatment of the, in particular comminuted, plants or plant components according to step 1) and / or 4), in particular or, with a mixture containing ethanol and water to obtain a product mixture containing polyphenols, 6) separating the, in particular comminuted, plants or plant components from the product mixture according to step 5) to obtain a liquid extract containing the polyphenols, 7) removing the ethanol from the liquid extract according to step 6) to obtain an aqueous extract containing the polyphenols, 8) treating the aqueous extract according to step 7) with the enzyme tannase to obtain an aqueous system containing gallic acid, 9) evaporative concentrating of the aqueous system containing gallic acid according to step 8) to obtain an aqueous concentrate, wherein ethanol is added in step 5) in an amount in the range from 60 to 90 percent by weight, based on the total weight of ethanol and the water.

8. Method according to one of claims 1 to 7, characterized in that the separation in step f) or in step 6) is carried out by means of a sieve.

9. Method according to one of the preceding claims, characterized in that the, in particular ground, preferably comminuted, plants or plant components are in step e) or step 5), respectively, are present immobilized, in particular immobilized in a portafilter.

10. Method according to one of the preceding claims, characterized in that the extractive treatment according to step e) or step 5), respectively, comprises a percolation method.

11. Method according to one of the preceding claims, characterized in that the amount of tannase in step e) or step 8), respectively is in the range from 0.1 U / g to 100.0 U / g, preferably in the range from 0.2 U / g to 50.0 U / g, based on the amount of plants or plant components.

12. Method according to one of the preceding claims, characterized in that the aqueous concentrate obtained by evaporative concentrating of the aqueous extract containing gallic acid obtained according to step k), or of the aqueous system containing gallic acid, according to step 9), respectively, represents a spissum extract.

13. Method according to claim 12, characterized in that the aqueous concentrate has a Brix value in the range from 1° to 100° Brix, preferably in the range from 10° to 70° Brix and particularly preferably in the range from 20° to 50° Brix.

14. Method according to one of claims 7 to 13, characterized in that the extractive treatment according to step 5) is carried out at temperatures in the range from 50 to 70°C, in particular in the range from 55 to 65°C.

15. Method according to one of the preceding claims, characterized in that the extractive treatment according to step e) or the treatment of the aqueous extract according to step 8) with the enzyme tannase, respectively, is carried out at temperatures in the range from 35 to 40°C.

16. Method according to one of claims 7 to 15, characterized in that ethanol is added in step 5) in an amount in the range from 70 to 85 percent by weight, based on the total weight of ethanol and the water.

17. Method according to one of the preceding claims, characterized in that the provided plant comprises or is fragrant sumac and / or that the plant components comprise or are leaves, bark and / or fruits, in particular fruits, of fragrant sumac.

18. Aqueous concentrate containing gallic acid, obtained according to a method according to one of the preceding claims, characterized by a dry mass in the range from 5 to 80 percent by weight, preferably in the range from 10 to 50 percent by weight and particularly preferably in the range from 15 to 40 percent by weight, in each case based on the total weight of the aqueous concentrate, by a pH value in the range from 1.5 to 5.5, preferably in the range from 1.75 to 4.5 and particularly preferably in the range from 2.0 to 4.0, by an amount of gallic acid of at least 10 g / kg dry mass, preferably at least 50 g / kg dry mass and particularly preferably at least 75 g / kg dry mass, and / or an amount of gallic acid in the range from 10 to 250 g / kg dry mass, preferably in the range from 50 to 200 g / kg dry mass and particularly preferably in the range from 75 to 175 g / kg dry mass, and by a relative density [20 / 20] in the range from 1.001 to 1.400, preferably in the range from 1.0100 to 1.2500, determined by way of the oscillating u-shape method according to the method mentioned in the description, wherein the aqueous concentrate has a Trolox-equivalent antioxidant capacity in the range from 500 to 6000 µmol / g, based on the dry mass of the extract, determined with the DPPH (2.2-diphenyl-1-picrylhydrazyl) assay according to the determination method mentioned in the description.

19. Foodstuff, in particular beverage, or dietary supplement, containing or formed from an aqueous concentrate according to claim 18.