ONION JUICE CONCENTRATE

Description

[0001] The present invention relates to an onion juice concentrate which has a particularly advantageous carbohydrate and flavor or odor profile, and to a method for producing such an onion juice concentrate.

[0002] In particular, the present invention relates to an onion juice concentrate with a particularly high fructan content and discloses for the first time the associated advantages in the processability and tolerability of such an onion juice concentrate, which make its use in the food industry particularly attractive.

[0003] Due to their intense and versatile flavor, onions are among the most popular ingredients in cooking. Depending on their composition and preparation, they can impart a mildly spicy to pungent and / or sweet aroma. Characteristic of the flavor and smell profile of onions are, in particular, the breakdown products of the sulfur-containing amino acid isoalliin, which are produced during onion processing and, in certain concentrations, can even irritate mucous membranes—for example, causing watery eyes when chopping onions. Furthermore, onions contain a wide variety of aromatic compounds, which, depending on their composition, influence the flavor profile and can, for example, impart or enhance an oniony, sulfurous, sweet, and / or astringent taste impression.

[0004] Onions are usually grown either as annual plants by sowing seeds and harvesting them in the same or the following year (seed onions), or in a two-year process by planting (setting) the plants grown in the previous year back into the ground (sets).

[0005] Unlike many other plants, onions do not store starch, but rather fructans as reserve carbohydrates. Fructans are oligo- or polysaccharides consisting of differently linked fructofuranose units bound to a sucrose molecule. Onion fructans are usually 1 to 5-chain and branched with a polymerization degree of 1 to 9, and are readily water-soluble. Examples of typical onion fructans include nystose, 1-kestose, 6-kestose, and fructosylnystose.

[0006] Inulin is a mixture of oligo- and polysaccharides made up of fructose units, belonging to the fructans, and possesses a range of beneficial properties that allow for diverse applications in food. First, it is a valuable dietary fiber and can replace other carbohydrates such as starch and—due to its sweet taste—even sugar in foods, thus reducing calories and promoting digestion. Furthermore, its creamy consistency makes it a suitable fat substitute in low-fat dairy products, and studies have shown it to have a positive effect on the absorption of minerals such as calcium and magnesium. Finally, inulin has even been observed to have a prebiotic effect, promoting the growth of beneficial gut bacteria. For information on the inulin content of onions, see, for example: Ernst et al., Characterization of Fructan Oligomers from Species of the Genus Allium L., J.Plant Physiol. Vol. 153, pp. 53-60 (1998); Niness, Inulin and Oligofructose: What Are They?, J Nutr. 1999 Jul;129(7 Suppl):1402S-6S.

[0007] CN103704653A relates to a concentrated onion juice and its manufacturing process, as well as a nutritious multi-purpose seasoning that can be used to improve the odor of meat and fish or added to soups, snacks and vegetable salads.

[0008] Within the scope of the present invention, it has been found that an onion juice concentrate with a particularly high fructan content and an overall advantageous carbohydrate profile can be obtained when sets of onions are processed into an onion juice concentrate using a method according to the invention.

[0009] Preferably, the resulting onion juice concentrate can be processed particularly well, as it does not burn, does not foam too much and is not sticky, and unwanted browning can be avoided.

[0010] The object of the present invention was to provide an onion juice concentrate which has a particularly advantageous composition.

[0011] In particular, the object of the present invention was to provide an onion juice concentrate with a carbohydrate profile that achieves the advantageous dietary effects described above.

[0012] Furthermore, it was an object of the present invention to provide an onion juice concentrate with a flavor and / or odor profile that is suitable for use as a flavor and / or odor mixture in food.

[0013] Finally, it was also the objective of the present invention to provide an onion juice concentrate which is characterized by particularly good processability.

[0014] These problems are solved according to the invention by an onion juice concentrate (K) produced by the process of the present invention and containing 20 to 45 wt.% fructans, as well as 1 to 22 wt.% fructose, 2 to 20 wt.% glucose, 3 to 25 wt.% sucrose and 0.5 to 10 wt.% cellobiose, each based on the total weight of the onion juice concentrate.

[0015] The onion juice concentrate according to the invention has a higher fructan content compared to conventional onion juice concentrates when compared to the sugars fructose, glucose and sucrose.

[0016] The increased fructan content improves the tolerability of the onion juice concentrate according to the invention. As already mentioned in the introduction, the high content of oligo- and polyfructose molecules has a positive effect on digestion and can bring additional health-promoting effects such as improved mineral absorption and a prebiotic effect.

[0017] The correlation between sugar and fructan content and the viscosity of onion juice concentrate shows that a higher sugar content lowers the viscosity, while a higher fructan content significantly increases it. The fructan and fructose content is particularly important with regard to the processability of the onion juice concentrate, as significantly better drying properties are achieved the higher the fructan-to-fructose ratio.

[0018] According to a preferred embodiment of an onion juice concentrate (K) according to the invention, the ratio of the total weight of fructan(s) to the total weight of fructose is 1 or more, particularly preferably 1.5 or more.

[0019] This makes the onion juice concentrate according to the invention particularly easy to process further and incorporate into numerous food products or semi-finished goods of varying consistencies. Preferably, the product dries thoroughly and completely without foaming or sticking. It is also advantageous that the onion juice concentrate according to the invention is preferably significantly lighter in color, i.e., less orange-brown, since it preferably does not brown during processing or drying and therefore does not undesirably discolor the food products in which it is used.

[0020] The onion juice concentrate (K) according to the invention is preferably characterized in that it contains one, two, several or all of the flavoring substances from the following group: 2-methyl-2-pentenal, propanal, hexanal, 2E-heptenal, dipropyl disulfide, dipropyl trisulfide, methylpropyl disulfide, dimethyl disulfide, dimethyl trisulfide, 1Z-propenyl propyl disulfide, 1E-propenyl propyl disulfide, cis-methyl-1-propenyl disulfide, trans-methyl-1-propenyl disulfide, propanethiol and 2-methyl butyraldehyde.

[0021] Onions contain a wide range of aromatic compounds that can impart a diverse flavor and aroma profile. Particularly characteristic are the aromatic compounds mentioned above, some of which only develop during the processing of onions and can variably influence the overall aroma.

[0022] Preferably, an onion juice concentrate (K) according to the invention also contains one or more substances selected from the group consisting of cinnamic acid amides and S-alkylated cysteine ​​derivatives, for example S-alk(en)yl cysteine ​​sulfoxides and S-alk(en)yl cysteines.

[0023] The use of an onion juice concentrate (K) according to the invention as a flavoring and / or odorant mixture or as a component thereof is particularly advantageous.

[0024] In particular, its use to convey or enhance one, several or all of the following taste and / or smell impressions is preferred: astringent, sulphurous, oniony, oniony fresh, sweet, oily, bitter, slightly roasted, slightly caramelized, pungent, biting, earthy, green (apple-like), green (grass-like), leeky, fatty, fresh, fried, umami, full-bodied and roasted.

[0025] The present disclosure therefore also relates to a flavor and / or fragrance mixture containing an onion juice concentrate (K) as described above.

[0026] Such a flavor and / or aroma mixture is suitable for a wide range of applications in seasoning and flavoring products, especially those with roasted and roasted aromas, and can be used in various forms, e.g., liquid, powder, or pressed or portioned for dissolving. Application in dry form, for example as a powder, is particularly preferred.

[0027] Furthermore, the disclosed flavor and / or odor mixtures may contain common additives, additional seasonings and flavorings, as well as flavor enhancers.

[0028] This disclosure also relates to a preparation intended for nutrition or enjoyment, containing an onion juice concentrate (K) according to the invention or a disclosed flavor and / or odor mixture, preferably wherein the total amount of onion juice concentrate (K) contained in the preparation is sufficient to impart or enhance one or more taste and / or odor impressions, preferably one, several, or all of the following taste or odor impressions: astringent, sulfurous, oniony, oniony fresh, sweet, oily, bitter, slightly roasted, slightly caramelized, pungent, biting, earthy, green (apple-like), green (grass-like), leeky, fatty, fresh, fried, umami, full-bodied, roasted. Furthermore, the onion juice concentrate according to the invention can create the impression of increased mouthfeel with savory flavors.

[0029] Such preparations can be both ready-to-eat products and semi-finished products.

[0030] As mentioned at the outset, the present invention also relates to a process for producing an onion juice concentrate (K) from sets of onions, comprising or consisting of the following step(s): (a) Providing an onion mash (M), (b) preparing an onion juice (S) from the onion mash (M), (c) separating the onion mash (M) from the onion juice (S) and pomace, (d) optionally adjusting the pH of the onion juice (S) to a pH in the range of 3 to 7, preferably 4 to 6, particularly preferably 4.5 to 5.5, (e) clarifying the onion juice, (f) preparing an onion juice concentrate (K) from the onion juice (S) to obtain an onion juice concentrate (K) containing 20 to 45 wt.% fructans, as well as 1 to 22 wt.% fructose, 2 to 20 wt.% glucose, 3 to 25 wt.% sucrose and 0.5 to 10 wt.% cellobiose, each based on the total weight of the onion juice concentrate, where step (b) comprises or consists of the following sub-steps: (b1) Heating the onion mash (M) to 30 to 60 °C, preferably to 40 to 55 °C, particularly preferably to 48 to 52 °C, (b2) Adding an enzyme mixture to the onion mash (M), (b3) Incubating the onion mash (M) for 1 hour or more, preferably for 2 hours or more.

[0031] In the context of this disclosure, the term "onion" covers all known varieties, including in particular common onions, sweet onions, red and white onions, shallots, spring onions, and pearl onions. These may have been grown in a one-year or two-year process (seed onions or sets).

[0032] In the context of the present invention, onion mash (M) means the (pre-)crushed and optionally (partially) cleaned onion material which is processed in the inventive method.

[0033] The onion juice (S) comprises all the essentially liquid substances released from the onion material, which are separated from the predominantly solid residues (pomace) in step (c).

[0034] In the context of the present invention, "separation" encompasses all methods known to those skilled in the art for (partially) separating different components of a mixture. In particular, methods such as pressing or filtering are suitable for separating the onion mash from the onion juice and pomace.

[0035] The "clarification" according to step (e) of the method according to the invention can be carried out using any method or device known to a person skilled in the art for the (partial) removal of impurities. For example, precipitation, filtration, ultrafiltration, microfiltration, reverse osmosis, or the use of separators or decanters can contribute to the clarification of the onion juice.

[0036] The onion juice concentrate produced by the inventive method has an advantageous composition as described above, both with regard to the sugar or fructan content and with regard to the taste or odor profile.

[0037] Furthermore, it is advantageously particularly easy to process further, as it preferably does not stick, burn, or foam excessively and has a lighter color (less orange-brown) than conventional onion juice concentrates. According to the invention, a preferred method is characterized in that step (a) comprises or consists of the following sub-steps: (a1) Prepare and optionally wash the sets of onions, (a2) Chop the onions from step (a1).

[0038] Preparing the onion pulp can include washing the onions, removing soil, stones, and optionally roots, shoots, or peels, as well as several processing steps, such as pre-shredding and subsequent grinding. Furthermore, rotten or diseased onions can be selectively removed.

[0039] The method according to the invention is characterized in that step (b) comprises or consists of the following sub-steps: (b1) Heating the onion mash (M) to 30 to 60 °C, preferably to 40 to 55 °C, particularly preferably to 48 to 52 °C, (b2) Adding an enzyme mixture to the onion mash (M), (b3) Incubating the onion mash (M) for 1 hour or more, preferably for 2 hours or more.

[0040] The use of certain enzymes can improve the breakdown of onion material, for example, by selectively breaking down cell walls. The resulting breakdown products have a beneficial effect—as described above—on the carbohydrate composition of the onion juice. Furthermore, this efficient breakdown promotes the release or formation (through reaction) of flavor compounds, leading to a particularly intense aroma in the resulting onion juice.

[0041] Suitable enzymes in this context include, for example, carbohydrases. This general term encompasses enzymes that can catalyze the breakdown of simple to very complex carbohydrates, such as those found in plant cell walls. This process produces various poly- and oligosaccharides, which may then be further broken down into di- and monosaccharides (simple sugars).

[0042] Examples of suitable carbohydrases that can be used in the process according to the invention are arabanase, cellulase, beta-glucanase, hemicellulase, xylanase, and pectinase. The use of a mixture comprising two, several, or all of these enzymes leads—as has been shown—particularly to the composition of the onion juice concentrate produced that is advantageous according to the invention.

[0043] According to a preferred embodiment of the process according to the invention, the enzyme mixture therefore contains one or more carbohydrases, wherein the or one carbohydrase or several or all of the carbohydrases is / are preferably selected from the group consisting of: arabanase, cellulase, beta-glucanase, hemicellulase, xylanase and pectinase.

[0044] A further preferred method according to the invention is characterized in that step (f) comprises or consists of the following sub-steps: (f1) Pasteurizing by injecting steam into the onion juice (S), (f2) optionally adding further ingredients to the onion juice (S), (f3) removing at least some of the water from the onion juice (S) to obtain an onion juice concentrate (K) of at least 30 ° Brix, preferably 65 to 85 ° Brix.

[0045] To obtain a food-grade and shelf-stable onion juice concentrate, the onion juice is first pasteurized. Various techniques for briefly heating the juice to temperatures at which microorganisms are (partially) killed are known to those skilled in the art. The injection of steam is particularly preferred in the process according to the invention, as it is easy and efficient to implement at this stage of the process and is also particularly energy-efficient.

[0046] Optionally, other ingredients can be added to the obtained onion juice so that they can be intensively mixed with the onion juice before it is concentrated.

[0047] Removing at least some of the water from the onion juice to obtain an onion juice concentrate (K) of at least 30 ° Brix, preferably 65 to 85 ° Brix, is preferably carried out by vacuum belt drying, spray drying, freeze-drying, roller drying, in a fluidized bed or vacuum thin-film evaporator, by other vacuum processes or membrane technologies, as well as by roasting or the use of plate condensers. Certain drying processes, such as roasting, can advantageously lead to the formation of further reaction aromas and thus to an intensification of the overall aroma of the onion juice concentrate produced according to the invention.

[0048] The values ​​given in °Brix refer to the density of the onion juice concentrate, where the density corresponds to that of a solution of sucrose in water containing the number of grams of sucrose per 100 g of solution specified in °Brix. For example, the onion juice concentrate has a density of 1 °Brix if it has the same density as a solution of 1 g of sucrose in 100 g of sucrose / water. Therefore, 10 °Brix corresponds to a density of 10 g of sucrose in 100 g of sucrose / water.

[0049] Finally, the present invention also relates to an onion juice concentrate as defined above, produced or producible by a process as described in the preceding sections.

[0050] The statements already made above regarding the onion juice concentrate according to the invention apply accordingly to an onion juice concentrate produced or producible according to the process of the invention. In particular, it has the advantageous composition and the particularly good processability – as described above.

[0051] The following examples are intended to further characterize the present invention without limiting its scope. Unless otherwise stated, all percentages refer to weight. Examples: Example 1: Production of onion juice concentrate:

[0052] According to the process described herein or above: Onions are washed, crushed into a mash, from which the onion juice is separated. After adjusting the pH to approximately 5, this juice is clarified and further processed according to the process described herein or above to produce onion juice concentrate, which has a composition according to the invention. This onion juice concentrate can be used both pure and in mixtures with carrier materials or various oils. Example 2: Application examples (not according to the present invention): 2.1 Fresh onion note (spray-dried):

[0053] 29% onion juice concentrate is dispersed with water, onion oil, and a carrier substance. The resulting slurry is spray-dried while being constantly stirred. 2.2 Sautéed onion profile (paste):

[0054] 58% onion juice concentrate and apple juice are mixed together with butter, heated and homogenized. 2.3 Fried onion profile (paste):

[0055] 80% onion juice concentrate is mixed with vegetable oil, heated and homogenized. 2.4 Cooked onion profile (viscous liquid):

[0056] 90% onion juice concentrate is mixed with protein building blocks and fructose, heated and homogenized.

Claims

1. Method for producing an onion juice concentrate (K) from onion sets, comprising or consisting of the following step(s): (a) providing an onion mash (M), (b) preparing an onion juice (S) from the onion mash (M), (c) separating the onion mash (M) from onion juice (S) and pomace, (d) optionally adjusting the pH value of the onion juice (S) to a pH in the range of 3 to 7, preferably 4 to 6, more preferably 4.5 to 5.5, (e) clarifying the onion juice, (f) preparing an onion juice concentrate (K) from the onion juice (S) so as to obtain an onion juice concentrate (K) containing 20 to 45 wt.% fructans, 1 to 22 wt.% fructose, 2 to 20 wt.% glucose, 3 to 25 wt.% sucrose, and 0.5 to 10 wt.% cellobiose, in each case based on the total weight of the onion juice concentrate, wherein step (b) comprises or consists of the following sub-steps: (b1) heating the onion mash (M) to 30 to 60 °C, preferably to 40 to 55 °C, more preferably to 48 to 52 °C, (b2) adding an enzyme mixture to the onion mash (M), (b3) incubating the onion mash (M) for 1 hour or more, preferably for 2 hours or more.

2. The method according to claim 1, characterized in that step (a) comprises or consists of the following sub-steps: (a1) providing and optionally washing onion sets, (a2) comminuting the onions from step (a1).

3. The method according to claim 1 or 2, characterized in that step (f) comprises or consists of the following sub-steps: (f1) pasteurizing by injection of steam into the onion juice (S), (f2) optionally adding further constituents to the onion juice (S), (f3) removing at least a portion of the water from the onion juice (S) to obtain an onion juice concentrate (K) having at least 30 °Brix, preferably 65 to 85 °Brix.

4. The method according to any one of claims 1 to 3, characterized in that the enzyme mixture comprises one or more carbohydrases.

5. The method according to claim 4, characterized in that the carbohydrase or one of the carbohydrases or two or more or all of the carbohydrases is / are selected from the group consisting of: arabanase, cellulase, beta-glucanase, hemicellulase, xylanase, and pectinase.

6. Onion juice concentrate (K) containing 20 to 45 wt.% fructans, 1 to 22 wt.% fructose, 2 to 20 wt.% glucose, 3 to 25 wt.% sucrose, and 0.5 to 10 wt.% cellobiose, in each case based on the total weight of the onion juice concentrate, produced or producible by a method according to any one of claims 1 to 5.

7. The onion juice concentrate according to claim 6, characterized in that the onion juice concentrate (K) contains one, two, more, or all of the flavor compounds from the following group: 2-methyl-2-pentenal, propanal, hexanal, 2E-heptenal, dipropyl disulfide, dipropyl trisulfide, methyl propyl disulfide, dimethyl disulfide, dimethyl trisulfide, 1Z-propenyl propyl disulfide, 1E-propenyl propyl disulfide, cis-methyl-1-propenyl disulfide, trans-methyl-1-propenyl disulfide, propanethiol, and 2-methyl-butyraldehyde.

8. The onion juice concentrate (K) according to claim 6 or 7, further containing one or more additional substances selected from the group consisting of cinnamic acid amides and S-alkylated cysteine derivatives, for example S-alk(en)yl cysteine sulfoxides and S-alk(en)yl cysteines.