Low methoxyl group, high calcium reactive pectin and preparation method thereof

Abstract

The present invention relates to a method for preparing a low-methoxyl, high-calcium reactive pectin and a low-methoxyl, high-calcium reactive pectin obtainable by the method. In addition, the present invention relates to the use of the low-methoxyl pectin according to the present invention for producing food and non-food products. In addition, an object of the present invention is to provide a product or a stable aqueous system prepared using the low-methoxyl pectin according to the present invention.

Description

Technical Field

[0001] The present invention relates to a method for preparing a low-methoxyl, high-calcium reactive pectin and a low-methoxyl, high-calcium reactive pectin obtainable by the method. Furthermore, the present invention relates to the use of the low-methoxyl pectin according to the invention in the production of products in the food and non-food sectors. Furthermore, an object of the present invention is a product or a stable aqueous system prepared by using the low-methoxyl pectin according to the invention. Background Art

[0002] Pectin is a plant polysaccharide, more specifically a polysaccharide uronide, which is basically composed of D-galacturonic acid units connected by α-1,4-glycosidic bonds. Low methoxy pectins are known in the art. Their degree of esterification is less than 50%. Low ester pectins are particularly used as gelling agents or thickeners for the production of liquid foods or gel-like foods. In addition to the food field, the pharmaceutical field is becoming increasingly important as an application field of pectin.

[0003] For gelation, low methoxy pectin requires polyvalent cations, which form chain associations with the carboxyl groups of the galacturonic acid structural units of the low methoxy pectin connected by axis-axis bonds, which is known in the literature as the egg-box model. In food, calcium ions are usually used as polyvalent cations. The hardness of the gel depends not only on the pectin structure, but also on many other factors, such as the content of low methoxy pectin, calcium ion concentration, soluble solids content and pH value.

[0004] In terms of structure, various parameters play a role in gel formation using pectin, such as the molecular weight of the pectin, the galacturonic acid content, the degree of esterification, and the distribution of the ester groups (block versus random).

[0005] As part of the preparation of foods, especially foods containing fruit, an appropriate amount of calcium salt is added to the corresponding low methoxyl pectin - usually low methoxyl, amidated or non-amidated pectin. Alternatively, a specially standardized low methoxyl pectin can be provided, i.e. a dry blend containing pectin and calcium salt.

[0006] One problem is that the dosage of calcium salt depends on the calcium content of the calcium salt and the respective application. When the appropriate amount of calcium salt is selected, the final soluble solids content and other characteristics of the manufactured product (especially fruit-containing products) and the food mix product manufactured using the product are particularly important. For example, the type of fruit used, the addition of milk or milk substitutes, and the pH value must be considered.

[0007] Another disadvantage of using low-methoxy, amidated or non-amidated pectins as thickeners to which calcium salts are added is that various problems may arise, in particular in the production of products with a relatively low soluble solids content, depending on the solubility of the calcium salts used in each case. For example, when using readily soluble calcium salts (e.g. calcium chloride or calcium lactate), a rapid reaction is usually observed due to the high calcium reactivity of low-methoxy pectins. This can lead to undesirable pre-gelation until the pectin precipitates as non-gelling calcium pectinate, followed by undesirable textural properties until the product syneresis. In contrast, a major problem when using poorly soluble calcium salts (e.g. calcium citrate or calcium phosphate) is that, due to the poor solubility, the dosage of calcium salt is often insufficient to achieve satisfactory gelation.

[0008] Another disadvantage of using low-methoxyl, amidated and non-amidated pectins is that the calcium salt to be used in each case must be stated in the ingredient list of the corresponding food mixture product, which prolongs the ingredient list and thus makes it less consumer-friendly. Furthermore, the organic certification of food mixture products, which is increasingly important for consumers, is only possible if the calcium salt used is also organic. The choice of calcium salt is therefore limited (in addition to its solubility properties) by such additional criteria that may have to be met. A major disadvantage of amidated pectins is that they themselves are not approved for use in organic products.

[0009] Alternatively, modified starch and non-modified starch can be used as thickeners for yogurt fruit products in the prior art. Modified starch is a food additive that carries a mandatory E number, and this labeling requirement does not apply to non-modified starch. Consumers generally believe that additives marked with E numbers are not of natural origin. Therefore, they have low consumer acceptance.

[0010] A particular disadvantage of using starch, in particular non-modified starch (without E number), as thickener, in particular for the production of fruit-containing preparations, is the relatively high dosage required, which has a negative impact on resource efficiency on the one hand and on the loss of unfavorable fruit flavor on the other hand. Another disadvantage is that the use of starch has an adverse effect on flavor release, i.e. it is associated with a relatively poor flavor release. As a result, it is often necessary to add flavoring agents, which prolongs the ingredient list of the corresponding food mix products and generally further reduces consumer acceptance. In addition, starch as a thickener has a relatively high cooking viscosity, which causes any fruit particles that may be present to be undesirably crushed or pureed during the cooking process.

[0011] In addition, the products described in the prior art, in particular the fruit-containing products intended for dairy products, usually have their pH adjusted to the natural pH of the corresponding dairy product. The pH of such fruit products is usually adjusted by pH adjusting agents (e.g. sodium citrate). This may require additional work and / or measurement steps. In addition, the corresponding pH adjusting agents not only expand the ingredient list, but may also have to be approved for organic products.

[0012] In general, the gelling agents or thickeners described in the prior art for producing pumpable, in particular fruit-containing, preparations with a relatively low soluble solids content (i.e. 10° to 45° Brix) must be considered unsatisfactory, in particular from a technical, economical and ecological point of view.

[0013] The production of high-quality low-methoxyl pectin is technically challenging. On the one hand, pectin can be de-esterified by acid or alkali treatment; however, this treatment also leads to hydrolytic cleavage of polygalacturonic acid chains, which has an adverse effect on the quality of pectin. In addition, de-esterification in an acidic environment is associated with a long incubation period. In addition, the resulting low-methoxyl pectin usually has a yellow hue. In the prior art, enzymatic pectin de-esterification using pectin methylesterase is also common. As an enzymatic reaction, it is particularly sensitive to reaction conditions (e.g., pH or the presence of calcium ions).

[0014] DE60122522T2 relates to pectins with a low degree of methoxylation and teaches a low methoxyl pectin with a degree of esterification of about 20 to 50% (paragraph

[0022] ). According to Table A (paragraph

[0158] ), when using this pectin to thicken a synthetic beverage, a specified amount of calcium (in the form of a CaCl2 solution) must be added.

[0015] WO99 / 37685 relates to a pectin for pasty materials and teaches a pectin with a molecular weight of about 30 to 40 kDa and a degree of esterification of less than 20% (claim 1), and the deesterification taught therein under alkaline conditions also leads to pectin hydrolysis (molecular weight reduction, see claim 7 and the examples on page 8, lines 21 to 23).

[0016] US3622559 relates to pectin with high breaking strength and teaches a process for preparing low methoxyl pectin with a degree of esterification of 7 to 8.5% (claim 1), wherein the deesterification is carried out in an acidic environment (0.7-1.5N HCl) over a long period of at least 24 hours (column 3, lines 3 to 7).

[0017] It is therefore an object of the present invention to overcome the above-mentioned and other disadvantages of the prior art. Summary of the invention

[0018] In a first aspect of the present invention, the object is achieved by a method for preparing low methoxyl pectin, the method comprising the steps of:

[0019] (a) providing a pectin-containing biomass raw material, wherein the pectin-containing biomass raw material comprises an insoluble fiber component and an insoluble protopectin component;

[0020] (b) extracting the pectin-containing biomass material with an aqueous medium having an acidic pH value under conditions where at least a portion of the pectin content is extracted;

[0021] (c) isolating pectin from the treated biomass feedstock and at least partially removing divalent cations from the pectin extract;

[0022] (d) concentrating the pectin extract from step (c) so that the content of pectin-containing substances in the pectin extract is 0.5 to 10% by weight based on dry matter;

[0023] (e) contacting the concentrated pectin extract from step (d) in aqueous solution with pectin methylesterase (EC 3.1.1.11) at a pH of 3.8 to 4.5;

[0024] (f) deesterifying the pectin by incubating the aqueous suspension from step (e) with pectin methylesterase to produce deesterified pectin;

[0025] (g) terminating the deesterification when the degree of esterification of the deesterified pectin is between 10% and 34%, advantageously between 10% and 28.0%, and

[0026] (h) thereby obtaining low methoxyl pectin;

[0027] Wherein, in step (f), the pH value is further adjusted by adding a substance or a mixture of substances that increase the pH value.

[0028] The production method according to the invention obtains low methoxyl pectin with high calcium reactivity. Such high calcium reactivity, low methoxyl pectin of the invention is also synonymously referred to as "low methoxyl" pectin hereinafter.

[0029] The low methoxyl pectin according to the present invention is a non-amidated pectin. In the production method according to the present invention, no aminolysis of high methoxyl pectin occurs, nor does a reaction of low methoxyl pectin with ammonia occur. The low methoxyl non-amidated pectin according to the present invention is also referred to as "low methoxyl pectin" hereinafter.

[0030] Surprisingly, it has been found that the low-methoxy pectins claimed herein show the best gelling properties and, depending on the proportion of dry matter, even without the addition of the commonly provided calcium salts (e.g. calcium lactate or calcium citrate). This surprising result is directly attributable to the very high calcium reactivity and very good solubility of the low-methoxy pectins claimed herein, especially in water.

[0031] The pH adjustment in the deesterification step maintains the optimum pH level for the pectin methylesterase, so that an esterification level below 34%, advantageously below 28.0%, can be achieved while maintaining a pumpable quality.

[0032] Furthermore, pH adjustment gently deesterifies the pectin without strong acidification or alkalization, thereby maintaining the structural integrity of the pectin backbone.

[0033] The process according to the invention can be carried out simply and economically using proven substances and can therefore be easily implemented in existing industrial processes and equipment for pectin processing.

[0034] The low-methoxyl pectin thus produced is therefore able to ensure adequate gelation without the addition of calcium ions, even in stable aqueous systems (e.g. fruit preparations) having only a low soluble solids content of 30 to 45%. In addition, the low-methoxyl pectin thus produced can also be used for the gelation of stable aqueous systems having an even lower soluble solids content of 10 to 30% (corresponding to 10 to 30° Brix). An example of this is fruit preserves.

[0035] Thus, advantageously, the addition of the calcium salts usually provided (e.g. calcium lactate or calcium citrate) can be omitted in fruit preparations. This result is due to the high calcium reactivity of the low methoxyl pectin according to the invention. Due to this high calcium reactivity, the calcium ion content of the fruit itself is sufficient to achieve the desired gelation.

[0036] It was found that the gel food products produced using the pectin produced according to the invention had a creamy, spreadable texture. In addition, they showed only a very low tendency to syneresis and no disturbing phase separation was observed.

[0037] Vegetable processing residues (e.g. apple pomace or citrus pomace) can be used as raw materials for the production process according to the invention. These processing residues are inexpensive, readily available in sufficient quantities, and provide a sustainable and ecologically sound source for the pectin of the invention.

[0038] Low methoxyl pectin is established and accepted in the food industry, allowing corresponding compositions to be used immediately internationally without lengthy approval procedures. DETAILED DESCRIPTION

[0039] In a first aspect, the present invention relates to a method for preparing low-methoxyl high-calcium reactive pectin, the method comprising preparation steps (a) to (g).

[0040] The raw material used in this method is a biomass raw material containing pectin, and the biomass raw material containing pectin comprises an insoluble fiber component and an insoluble protopectin component. The biomass raw material containing pectin is a plant material comprising a primary cell wall. The primary wall of the plant cell is composed of pectin, cellulose, hemicellulose and protein. Therefore, plants or plant parts rich in primary walls are typical raw materials for pectin separation. These include, for example, apple pomace, citrus pomace or beet pulp.

[0041] Extraction in aqueous suspension in an acidic pH environment according to step (b) breaks down the biomass feedstock. Incubation in an aqueous liquid (as a suspension) causes the biomass feedstock to swell and become permeable, which allows the acid to penetrate into the plant material, where it can convert the protopectin into water-soluble pectin. This water-soluble pectin can now be dissolved out of the permeabilized biomass material while retaining the pectin structure, thereby being present in the aqueous liquid as extractable pectin.

[0042] Then, in step (c), the pectin dissolved in the liquid is separated from the solid biomass feedstock treated according to step (b). This is usually done by solid-liquid separation. Step (c) also includes at least partially removing divalent cations, such as magnesium and especially calcium, from the extract.

[0043] In step (d), the pectin extract is concentrated so that the content of pectin-containing substances in the pectin extract is 0.5 to 10% by weight, preferably 6 to 8% by weight, based on dry matter. The results show that pectin methylesterase exhibits satisfactory deesterification only at this adjusted pectin dry matter.

[0044] Deesterification of pectin is achieved by contacting the concentrated pectin extract in aqueous suspension with pectin methylesterase (EC 3.1.1.11) at a pH of 3.8 to 4.5 according to step (e) followed by incubation under suitable reaction conditions according to step (f).

[0045] Once the desired degree of esterification is reached, the enzymatic deesterification reaction is terminated according to step (g). This can be accomplished, for example, by pectin precipitation or enzyme denaturation.

[0046] In the process according to the invention, it is essential to adjust the pH during the incubation of the deesterification reaction mixture according to step (f). This is done by adding a substance or a mixture of substances which raises the pH value.

[0047] In the method according to the invention, biocatalytic (i.e. enzymatic) deesterification occurs. Due to the setting of controlled reaction conditions (e.g. pH or calcium ion concentration), mild deesterification with a degree of esterification of less than 34% (advantageously less than 28.0%) can be achieved without the need for additional chemical deesterification (i.e. by exposure to acid, base or ammonia).

[0048] In a preferred embodiment, the pectin-containing biomass raw material is a fruit selected from the group consisting of citrus, apple, beet, sunflower infructescence, rose hip, quince, apricot, cherry, carrot, and mixtures thereof. In a preferred form, the pectin-containing biomass raw material is a fruit component of such fruit or a residue resulting from a processing operation of such fruit, such as a juice extraction process (e.g., apple or citrus) or a sugar extraction process (e.g., beet).

[0049] In a second aspect, the present invention provides a method for producing low-methoxyl pectin from a pectin raw material. In contrast to the pectin-containing biomass raw material of the first aspect of the present invention, the pectin in the pectin raw material is already present as an extracted (and therefore isolated pectin in solid form). Therefore, the already extracted raw material (which is usually present as high-methoxyl pectin) can also be advantageously modified by the esterification method according to the present invention, in which it is converted into a low-methoxyl high-calcium reactive pectin.

[0050] According to the method for producing low methoxyl pectin in the second aspect, the method comprises the following steps:

[0051] (b1) providing a pectin raw material in a dry state;

[0052] (c1) preparing an aqueous solution of the pectin raw material from step (b1) so that the content of pectin-containing substances in the pectin-containing solution is 0.5-10% by weight based on dry matter;

[0053] (e) contacting the concentrated pectin-containing solution from step (c1) with pectin methylesterase (EC 3.1.1.11) in aqueous solution at a pH of 3.8 to 4.5;

[0054] (f) deesterifying the pectin by incubating the aqueous solution from step (e) with pectin methylesterase to produce deesterified pectin;

[0055] (g) terminating the deesterification when the degree of esterification of the deesterified pectin is between 10% and 34%, advantageously between 10% and 28.0%, and

[0056] (h) thereby obtaining low methoxyl pectin;

[0057] Wherein, in step (f), the pH value is further adjusted by adding a substance or a mixture of substances that increase the pH value.

[0058] As described above, a dried and therefore solid pectin raw material is provided as starting material in step (b1 ).

[0059] According to step (c1) of the method, a pectin raw material is dissolved in an aqueous liquid to produce an aqueous solution. In the process, the pectin is dissolved so that the content of pectin-containing substances is 0.5-10% by weight based on dry matter. The results show that pectin methylesterase exhibits satisfactory deesterification only at this adjusted pectin dry matter.

[0060] Deesterification of pectin is achieved by contacting the concentrated pectin extract in aqueous suspension with pectin methylesterase (EC 3.1.1.11) at a pH of 3.8 to 4.5 according to step (e) followed by incubation under suitable reaction conditions according to step (f).

[0061] Once the desired degree of esterification is reached, the enzymatic deesterification reaction is terminated according to step (g). This can be accomplished, for example, by pectin precipitation or enzyme denaturation.

[0062] Similarly to the first aspect of the invention, it is also essential in the method according to the second aspect of the invention that the pH is adjusted during the incubation of the deesterification reaction mixture according to step (f). This is done by adding a substance or a mixture of substances that raises the pH.

[0063] In a preferred embodiment, the pectin raw material is obtained from a fruit selected from the group consisting of citrus, apple, beet, sunflower infructescence, rose hip, quince, apricot, cherry, carrot and mixtures thereof.

[0064] In a particular embodiment, the pectin raw material is obtained from citrus or apple raw materials and is therefore advantageously of natural origin. Vegetable processing residues (e.g., citrus pomace or apple pomace) are often used to separate the pectin raw material. These are readily available in sufficient quantities, providing a sustainable, ecologically healthy source of the desired natural raw materials. Among other things, citrus pectins with different degrees of esterification can be obtained from citrus pomace. Accordingly, apple pectins with different degrees of esterification can be obtained from apple pomace.

[0065] In the method according to the first aspect of the invention, the pectin-containing biomass raw material can be in a wet state, a non-dried state or a dried state. Therefore, during the juice production process, the pomace is obtained in the form of a wet mass. In the method, this wet pomace can initially be used as a fresh wet biomass as the pectin-containing biomass raw material. Alternatively, the pomace can also be frozen, and the method then starts with the frozen pomace, and in the first step the frozen pomace is thawed.

[0066] In a particularly preferred embodiment, the pectin-containing biomass raw material is citrus pomace or apple pomace. These pomace are readily available in sufficient quantities and provide a sustainable and ecologically sound source of the desired natural raw materials. Among other things, citrus pectin with different degrees of esterification can be obtained from citrus pomace. Correspondingly, apple pectin with different degrees of esterification can be obtained from apple pomace.

[0067] Citrus pulp from a wide variety of citrus fruits can be used to isolate citrus pectin. Examples are listed herein in a non-limiting manner: citrus (Citrus reticulata), clementine (Citrus×aurantium Clementine group, synonym: Citrus clementina), satsuma (Citrus×aurantium Satsuma group, synonym: Citrus unshiu), wild mandarin (Citrus mangshanensis), orange (Citrus×aurantium orange group, synonym: Citrus sinensis), bitter orange (Citrus×aurantium bitter orange group), bergamot (Citrus×limon bergamot group, synonym: Citrus bergamia), grapefruit (Citrus maxima), grapefruit (Citrus×aurantium grapefruit group, synonym: Citrus paradisi), pomelo (Citrus×aurantium pomelo The present invention relates to a kind of lemon fruit, including Citrus × aurantiifolia, Citrus × aurantiifolia, Citrus × latifolia, Citrus × hystrix, Citrus × jambhiri, Citrus × limon lemon group, Citrus × medica and Citrus japonica, which are synonymous with Fortunella. Among them, Citrus × aurantii orange group and Citrus × limon lemon group are preferred.

[0068] Acid extraction according to step (b)

[0069] The extraction in step (b) of the process serves to remove at least part of the pectin from the cell association by converting a partial fraction of the protopectin into soluble pectin.

[0070] The extraction conditions in step (b) make the pectin extracted during the extraction method high methoxyl pectin with high gel strength and good viscosity increasing property, and therefore it is also referred to as "high-quality pectin" in the context of this application.

[0071] The acid extraction according to step (b) is a full pectin extraction, as the pectin that goes into solution is subsequently separated from the fibrous material by solid-liquid separation according to step (c).

[0072] The high-quality pectin obtained by partial extraction is high methoxy pectin. According to the invention, high methoxy pectin is a pectin with a degree of esterification of at least 50%. The degree of esterification describes the percentage of carboxyl groups in the galacturonic acid units of the pectin that are present in esterified form (e.g. as methyl esters). The degree of esterification can be determined by the method according to JECFA (Topic 19-2016, Joint FAO / WHO Expert Committee on Food Additives).

[0073] According to an advantageous embodiment, the degree of esterification of high-quality pectin (preferably high methoxy soluble citrus pectin or apple pectin) is 50 to 80%, preferably 60 to 80%, particularly preferably 70 to 80%, and particularly preferably 72% to 75%. For example, the degree of esterification of high methoxy soluble pectin (preferably high methoxy soluble citrus pectin or apple pectin) can be 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79% or 80%.

[0074] According to one embodiment, the viscosity of high-quality pectin (preferably high methoxy soluble citrus pectin) measured in mPas is 400 to 1000 mPas, preferably 500 to 1000 mPas, more preferably 600 to 1000 mPas, and particularly preferably 700 to 1000 mPas. The viscosity of high-quality pectin (preferably high methoxy soluble citrus pectin) may be 550 mPas, 600 mPas, 650 mPas, 700 mPas, 750 mPas, 800 mPas, 850 mPas, 900 mPas or 950 mPas.

[0075] According to one embodiment, the gel strength of high-quality pectin (preferably high methoxy soluble citrus pectin) measured in ° SAG is 150 to 260 ° SAG, preferably 200 to 260 ° SAG, particularly preferably 220 to 260 ° SAG, and especially preferably 230 to 245 ° SAG. For example, the gel strength of high methoxy soluble pectin (preferably high methoxy soluble citrus pectin) may be 160 ° SAG, 170 ° SAG, 180 ° SAG, 190 ° SAG, 200 ° SAG, 210 ° SAG, 220 ° SAG, 230 ° SAG, 240 ° SAG or 250 ° SAG.

[0076] According to one embodiment, the gel strength of high-quality pectin (preferably high methoxy soluble apple pectin) measured in ° SAG is 150 to 250 ° SAG, preferably 170 to 240 ° SAG, particularly preferably 180 to 220 ° SAG, and especially preferably 190 to 200 ° SAG. For example, the gel strength of high methoxy soluble pectin (preferably high methoxy soluble apple pectin) can be 160 ° SAG, 170 ° SAG, 180 ° SAG, 190 ° SAG, 191 ° SAG, 192 ° SAG, 193 ° SAG, 194 ° SAG, 195 ° SAG, 196 ° SAG, 197 ° SAG, 198 ° SAG, 199 ° SAG, 200 ° SAG, 210 ° SAG, 220 ° SAG, 230 ° SAG or 240 ° SAG.

[0077] The pectin-containing biomass raw material is present in the form of an aqueous suspension during the decomposition process. The suspension according to the present invention is a non-homogeneous mixture of a liquid and a solid (raw material particles) finely distributed therein. Since the suspension tends to settle and phase separate, the particles are appropriately kept in the suspension by shaking or stirring, i.e., no dispersion would mean that the particles are mechanically crushed (sheared) and thus finely dispersed.

[0078] To achieve an acidic pH, the person skilled in the art can use all acids or acidic buffer solutions known to him. For example, organic acids can be used which act as calcium chelators and can thus bind excess calcium ions. Examples of such chelating acids are citric acid, gluconic acid or oxalic acid.

[0079] Alternatively or in combination, an inorganic acid may be used. Some examples are sulfuric acid, hydrochloric acid, nitric acid or sulfurous acid. Preferably nitric acid or sulfuric acid is used.

[0080] In the extraction in step (b) of the method, the pH of the suspension is from pH 0.5 to 4.0, preferably from pH 1.0 to 3.5, particularly preferably from pH 1.0 to 3.0. For example, the pH at which the acidic decomposition is carried out is: 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8 or 2.9.

[0081] In the extraction, the incubation temperature is 60° C. to 95° C., preferably 70° C. to 90° C., particularly preferably 75° C. to 85° C. For example, the extraction temperature is 76° C., 77° C., 78° C., 79° C., 80° C., 81° C., 82° C., 83° C. or 84° C.

[0082] In the extraction, the dry matter of the aqueous suspension is suitably 0.5% to 5% by weight, preferably 1% to 4% by weight, particularly preferably 1.5% to 3% by weight. For example, the dry matter for acid decomposition can be 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8% or 2.9%.

[0083] During the decomposition process, the aqueous suspension is suitably set in motion by applying a force, such as stirring or shaking. This is preferably done in a continuous manner so that the particles in the suspension remain suspended.

[0084] Separation and removal of cations according to step (c)

[0085] In step (c) of the method, the extracted pectin dissolved in the liquid is separated from the treated biomass so that it can be used for further processing. The separation is carried out as a single-stage solid-liquid separation or a multi-stage solid-liquid separation.

[0086] Advantageously, the decomposed material is subjected to a multi-stage solid-liquid separation. Preferably, a first separation of particles is carried out by a decanter and a second separation of particles is carried out by a separator. In this context, in contrast to a fractionation process, the separation of solids and liquids from the aqueous fiber suspension is independent of the particle size.

[0087] Alternatively, larger particles can also be separated in step (c). This is preferably done by classification. In the context of the present invention, classification is understood to be the separation of the dispersed solid mixture into fractions according to particle size. In the simplest case, two fractions are produced, but as part of the classification, two or three particle fractions with a specific particle distribution can also be produced. The classical method herein is screening.

[0088] In this context, it is particularly advantageous to separate particles having a particle size of greater than 500 μm, preferably greater than 400 μm, most preferably greater than 350 μm. The separation is advantageously carried out using a filter or a sieve drum, which removes coarse particle impurities from the raw material and insufficiently decomposed material. Whether this optional separation step is necessary depends on the hardness of the fiber material to be decomposed. This separation step is usually required for citrus fiber, but apple fiber is decomposed into fine fibers during the acid hydrolysis step, so this separation step can usually be omitted.

[0089] Alternatively, wet sieving can be used as the sieving method.

[0090] The skilled person is familiar with many screening machines for carrying out the classification process and he will select the screening machine according to the fiber particle size present and the fact that moist or wet material is present. Examples of screening machines include cantilever screening machines, elliptical screening machines, eccentric screening machines, linear screening machines, throwing screening machines, flat screening machines, agitator screening machines, air jet screening machines and vortex screening machines.

[0091] The fractionation treatment in step (c) may be performed during single-stage separation or multi-stage separation of the decomposed material from the aqueous liquid, before or after the separation.

[0092] In addition to pectin separation, step (c) also includes removing divalent cations. Remove at least part of the divalent cations, preferably completely remove the divalent cations. Removal according to the present invention refers to the functional removal of cations removed from the solution and by a chelating agent. In the functional removal, the divalent cations present in the solution no longer form a complex with the pectin due to its chelation. These cations are preferably magnesium or calcium, particularly calcium. The removal of divalent ions in step (c) can be carried out in a variety of ways.

[0093] Thus, in one embodiment, a cation exchanger material applied in a batch process or a column process may be used.

[0094] For example, inorganic substances such as zeolites can be used as cation exchanger materials. However, preferably, organic substances (in this case, synthetic resin-based cation exchangers) are used as exchanger materials. For example, organic base-based cation exchangers can be used as cation exchanger materials, which are weak bases and can carry tertiary amine groups as functional groups. Examples include cation exchange resins Purolite A 100Plus and Purolite PPC 150S (Lenntech, Delfgauw, the Netherlands).

[0095] In an alternative embodiment, chelating agents, ie inorganic or organic substances capable of fixing divalent cations in stable cyclic complexes (so-called chelates), can be used here to remove divalent ions.

[0096] In another embodiment, the removal of divalent ions can be accomplished by precipitation into sparingly soluble salts. For example, calcium ions can be precipitated into sparingly soluble calcium oxalate by adding a soluble oxalate (e.g., sodium oxalate).

[0097] The removal of divalent cations may be performed before, during or after the pectin separation in step (c).

[0098] Therefore, the cation exchanger can be added as particulate material before the pectin separation, so that the separation from the solid cation exchanger is also achieved by pectin separation as solid-liquid separation.

[0099] Concentrating the pectin extract of step (d)

[0100] In step (d), the pectin extract obtained in step (c) is concentrated to obtain a pectin extract having a pectin-containing substance content of 0.5 to 10 weight percent based on dry matter. Various methods for concentrating aqueous solutions are known to those skilled in the art. For example, water can be concentrated by evaporation as a solvent, preferably under vacuum to reduce the boiling temperature. Other examples include ultrafiltration, semipermeable membrane reverse osmosis and organic solvent precipitation (and subsequent absorption in a reduced volume solvent) pectin.

[0101] Enzymatic deesterification according to step (e)

[0102] According to the invention, in the deesterification according to step (e), at least one pectin methylesterase (EC 3.1.1.11) is added to the aqueous pectin solution.

[0103] Pectin methylesterase hydrolyzes the methyl ester of the galacturonic acid group in pectin to form polygalacturonic acid and methanol. The resulting low-methoxyl pectin can form gels in the presence of multivalent cations (even in the absence of sugars) and can also be used over a wide pH range.

[0104] Pectin methylesterase (abbreviation: PME, EC3.1.1.11, also known as: pectin demethoxylase, pectin methoxylase) is an enzyme commonly found in the cell walls of all higher plants and some bacteria and fungi, which cleaves the methyl esters of pectin, thereby forming polygalacturonic acid and releasing methanol. Many isoforms of PME have been isolated, all of which can be used for enzymatic deesterification according to the present invention. Therefore, many isoforms of PME have been isolated from plant pathogenic fungi such as Aspergillus foetidus and Phytophthora infestans, as well as from higher plants such as tomatoes, potatoes and oranges. Fungal PME exhibits optimal activity at a pH of 2.5 to 5.5, while plant PME exhibits optimal activity at a pH of 5 to 8. The relative molecular mass is 33,000 to 45,000. The enzyme exists in monomeric form and is glycosylated. The K of fungal PME M The K value of pectin ranged from 11 to 40 mM, the K of plant PME M Pectin values ​​are 4-22 mM. Commercially available PME preparations are obtained from the supernatant of fungal mycelial cultures or, when obtained from plants, from fruits (orange peel, lemon peel, tomato). Preferred pectin methylesterases have an optimum pH of 2 to 5 and an optimum temperature of 30 to 50°C, although significant enzyme activity can be observed as low as 15°C, depending on the enzyme.

[0105] The table below shows some examples of commercially available PMEs and their optimal values ​​for reactions:

[0106]

[0107] In the enzymatic deesterification, the aqueous solution contains a total activity of pectin methylesterase of 100 to 10,000 units / L, advantageously 500 to 5000 units / L, particularly advantageously 1000 to 2500 units / L.

[0108] In the enzymatic deesterification, the incubation time with at least one pectin methylesterase in aqueous solution is 10 to 20 hours, preferably 12 to 18 hours. The incubation time in this case can be, for example, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours or 19 hours. In this article, the reaction time of the deesterification reaction depends specifically on the pectin concentration, the corresponding PME isoform, the addition rate, the solvent or solvent mixture, the selected pH value or pH value level and the deesterification temperature.

[0109] In the enzymatic deesterification, the incubation temperature with at least one pectin methylesterase in aqueous solution is from 10°C to 70°C, preferably from 20°C to 60°C, particularly preferably from 30°C to 50°C. In this regard, the incubation temperature can be, for example, 20.5°C, 21.0°C, 21.5°C, 22.0°C, 22.5°C, 23.0°C, 23.5°C, 24.0°C, 24.5°C, 25.5°C, 26.0°C, 26.5°C, 27.0°C, 27.5°C, 28.0°C, 28.5°C, 29.0°C, 29.5°C, 30.5°C, 31.0°C, 31.5°C, 32.0°C, 32.5°C, 33.0°C, 33.5°C, 34.0°C, 34.5°C, 35.5°C, 36.0°C, 36.5°C, 37.0°C, 37.5°C, 38.0°C, 38.5°C, 39.0°C, 39.5°C, 40.0°C , 40.5°C, 41.0°C, 41.5°C, 42.0°C, 42.5°C, 43.0°C, 43.5°C, 44.0°C, 44.5°C, 45.0°C, 45.5°C, 46.0°C, 46.5°C, 47.0°C, 47.5°C, 48.0°C, 48.5°C, 49.0°C, 49.5°C, 50.0°C, 50.5°C, 51.0°C, 51.5°C, 52.0°C, 52.5°C, 53.0°C, 53.5°C, 54.0°C, 54.5°C, 55.0°C, 55.5°C, 56.0°C, 56.5°C, 57.0°C, 57.5°C, 58.0°C, 58.5°C, 59.0°C or 59.5°C. In the enzymatic deesterification reaction, the choice of temperature depends specifically on the activity range of the respective enzyme isoform or enzyme mixture.

[0110] In the enzymatic deesterification, the initial pH at which the incubation is carried out in aqueous solution with at least one pectin methylesterase is 3.8 to 4.5, preferably 4.0 to 4.3, particularly preferably 4.1 to 4.2. In this case, the pH may be, for example, 3.9, 4.0, 4.1, 4.2, 4.3 or 4.4. In this context, the choice of pH range or pH value depends specifically on the activity range of the corresponding enzyme or enzyme mixture, and in order to ensure effective deesterification while preventing in situ gelation of the deesterified pectin, the pH value must be at least 3.8, preferably at least 4.0.

[0111] In the enzymatic deesterification, the dry matter in the aqueous suspension is 0.5% to 10% by weight, preferably 4% to 10% by weight, particularly preferably 5% to 9% by weight, and especially preferably 6% to 8% by weight. In this case, the dry matter may be, for example, 0.6%, 0.7%, 0.8%, 0.9%, 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, 6.0%, 6.5%, 7.0% or 7.5%.

[0112] In the deesterification process, the aqueous solution is appropriately moved during incubation by applying force. This can be done by shaking or stirring the solution, taking care not to cause the enzyme to bubble.

[0113] Another optional embodiment of the method provides that the calcium ion concentration of the pectin present in step (e) is less than 0.10% by weight, advantageously less than 0.08% by weight, in particular less than 0.05% by weight. In this case, the calcium ion concentration of the high methoxy pectin is reduced in advance (e.g., using a cation exchanger) to a value within the above range. As a result of the cation exchanger treatment, the calcium ion concentration of the high methoxy pectin in step (e) may be, for example, less than 0.09%, 0.08%, 0.07%, 0.06%, 0.05%, 0.04%, 0.03%, 0.02% or 0.01% by weight.

[0114] The degree of esterification of pectin during the deesterification reaction is easy to control and adjust.

[0115] In order to achieve a predetermined degree of esterification, the degree of esterification can be determined or controlled at predetermined time intervals during the deesterification reaction using the analytical method described further below (see test method 1.1). Once the predetermined degree of esterification has been reached, the deesterification reaction can be terminated in a targeted manner by quenching with at least one alcohol (i.e. precipitation of low-methoxy pectin, and / or heating and / or addition of at least one inhibitor (in particular an enzyme inhibitor)).

[0116] Adjustment of pH in step (f)

[0117] According to the invention, in the method according to one of the preceding claims, the pH is adjusted by adding a substance or a substance mixture which increases the pH. The addition of a substance which increases the pH has proven to be advantageous from a process engineering point of view, since the pH which has been lowered due to the enzymatic deesterification (conversion of neutral ester groups into carboxylic acid groups) is thereby raised again in a controlled manner, maintaining the optimum pH range with regard to pectin quality and enzyme activity.

[0118] In one embodiment, the pH adjustment in step (f) is to increase the pH stepwise by discretely adding a substance or a mixture of substances that increase the pH value. Such discrete additions can be performed as a single addition or multiple additions (e.g., two, three, four, or five additions) during the enzymatic esterification process.

[0119] Discrete addition of the pH-raising substance or mixture of substances can be performed either as a function of the incubation time or when a specific pH value is reached.

[0120] Thus, discrete additions of the pH-increasing substance or mixture of substances may be performed such that the incubation time is from 1 to 6 hours, preferably from 1.5 to 4 hours, more preferably from 2 to 3 hours.

[0121] Thus, discrete addition of the substance or substance mixture which increases the pH value may be performed when a pH value of 3.5 to 4.5 is reached, preferably a pH value of 3.7 to 4.2, more preferably a pH value of 3.8 to 4.1.

[0122] In an alternative embodiment, the pH adjustment in step (f) is a pH maintenance step by continuous addition of a substance or mixture of substances that increases the pH value.

[0123] In a preferred embodiment, the substance that increases the pH value is a base. The base can be added as a single substance or as a substance mixture, the substance mixture is preferably an aqueous solution of the corresponding base.

[0124] A person skilled in the art can use bases known to him. Preferably, the base is selected from ammonia, sodium hydroxide or potassium hydroxide.

[0125] In an alternative embodiment, the substance that increases the pH value is a weak acid salt or a weak alkaline salt. The salt can be added as a single substance or as a substance mixture, and the substance mixture is preferably an aqueous solution of the corresponding salt.

[0126] A person skilled in the art can use salts known to him. Preferably, the weakly acidic salt or weakly basic salt is selected from potassium carbonate, sodium carbonate, sodium bicarbonate and potassium bicarbonate.

[0127] In another alternative embodiment, the pH-raising substance mixture is a weakly acidic buffer system or a weakly alkaline buffer system.

[0128] The skilled person in the art can use the buffer system known to him. Preferably, the weakly acidic buffer system or weakly alkaline buffer system is selected from carbonic acid / carbonate buffer, acetic acid / acetate buffer, phosphate buffer, ammonia buffer, HEPES buffer, PBS buffer and MES buffer.

[0129] The low methoxyl pectin obtained by this process may then be suitably isolated from the deesterified solution according to step (h). This may conveniently be carried out by precipitating the pectin with a water-miscible organic solvent.

[0130] For this purpose, the deesterified solution can be concentrated before the precipitation step. This can be carried out by, for example, membrane filtration or vacuum evaporation. In the case of reclaiming pectin, it is advantageous to concentrate before the deesterification step. However, in alternative embodiments, it is also possible to concentrate after the deesterification.

[0131] Water-miscible, thermally stable, volatile solvents containing only carbon, hydrogen and oxygen, such as alcohols, ethers, esters, ketones and acetals, are particularly suitable for carrying out the precipitation step according to the invention. Preferably, ethanol, n-propanol, isopropanol, methyl ethyl ketone, 1,2-butanediol-1-methyl ether, 1,2-propylene glycol-1-n-propyl ether or acetone are used.

[0132] An organic solvent is referred to herein as "water-miscible" if it exists as a single-phase liquid in a 1 :20 (v / v) mixture with water.

[0133] Typically, solvents are used which are at least 10% water miscible, have a boiling point below 100°C and / or have fewer than 10 carbon atoms.

[0134] The water-miscible organic solvent as a component of the washing liquid is preferably an alcohol, advantageously selected from methanol, ethanol and isopropanol. In a particularly preferred embodiment it is isopropanol.

[0135] Pectin can be dehydrated, dried and ground. Dehydration is performed before the drying step to remove a large amount of water. Although any known method can be used for dehydration, it is preferred to treat the pectin precipitate with alcohol. The water / alcohol phase formed during the dehydration process is substantially removed by decantation, centrifugation or filtration using known procedures.

[0136] Drying is achieved by known technology, for example, in an atmospheric oven or a reduced pressure oven, the moisture content reaches less than about 50 weight %, preferably less than about 25 weight %. The drying temperature is maintained below the temperature at which pectin begins to lose its characteristics (for example, in terms of color or molecular weight). Any known grinding process can be used to grind the pectin product into the desired particle size. It is particularly preferred that the final product is a dry powder form with a moisture content of about 12 weight % or less. The dry powder form means that the product can be poured without a large amount of baking. The preferred final product is a powder form for ease of use.

[0137] The low methoxyl pectin according to the present invention can also be mixed with a standardizing agent to form standardized low methoxyl pectin.

[0138] "Standardizer" in the sense of the present invention is defined as an uncharged organic molecule with good water solubility. Standardizers are used to standardize products. The same controlled manufacturing process produces pectins with predetermined properties. However, due to raw material-related variations in the pectin composition, pectins have certain variations (e.g. related to gel hardness or gel viscosity). Adding a standardizer significantly reduces the range of variation, thereby standardizing pectins. This allows for a constant dosage between batches.

[0139] Examples of standardizing agents include monosaccharides, oligosaccharides, polysaccharides or sugar alcohols, or combinations thereof.

[0140] In the case of monosaccharides or oligosaccharides, the skilled person can utilize all sugars used in the food industry. The following are examples of sugars that can be used: glucose, sucrose, fructose, invert sugar, isoglucose, mannose, melezitose, maltose, rhamnose, the sugar being preferably sucrose or glucose.

[0141] A standardizing agent such as glucose or sucrose may be added to the low methoxy pectin of the present invention in a proportion of 20 to 50% by weight based on the low methoxy pectin.

[0142] Low methoxyl pectin

[0143] In a third aspect of the present invention, the object of the present invention is achieved by providing a low methoxy pectin obtained or obtainable according to the method of the present invention, wherein the degree of esterification of the low methoxy pectin is 10% to 34%, advantageously 10% to 28.0%. For example, the degree of esterification of the low methoxy pectin can be 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28.0%, 29%, 30%, 31%, 32% or 33%.

[0144] In one embodiment, the calcium sensitivity of the low methoxyl pectin according to the invention is 300 HPE to 3000 HPE. It therefore exhibits an extremely high calcium sensitivity, which allows the pectin according to the invention to be used in products without the need for a separate addition of calcium salts. Here, the amount of calcium contained in the food (e.g., fruit products) is sufficient for gelation.

[0145] According to the invention, the term "calcium sensitivity" is understood as a measure of the firmness of a gel which is prepared with sucrose in a buffer and formed at 22° Brix at a pH of about 3.0 in the presence of a defined calcium ion concentration. The calcium sensitivity is determined after cooling in a water bath at 20° C. for two hours. The calcium sensitivity is determined using a Herbstreith Pectinometer Mark IV. The method used is hereinafter referred to as the calcium sensitivity test, the value measured is the calcium sensitivity, the unit of measurement being the HPE (Herbstreith Pectinometer Units, German: Herbstreith Pektinometer Einheiten).

[0146] Another embodiment of the low methoxyl pectin provides that the low methoxyl pectin is in the form of a powder, a liquid, or a suspension or solution in a solvent selected from the group consisting of water and water-miscible solvents and mixtures thereof.

[0147] "Miscible" means in this context that the two solvents form one phase at least during the reaction (especially during the gelation process), ie do not exist as two phases.

[0148] The term "water-miscible solvent" includes alcohols (especially methanol, ethanol, n-propanol and isopropanol) and other organic solvents (such as acetone, acetonitrile, methyl acetate, ethyl acetate) and mixtures thereof. The term "alcohol" also includes multivalent alcohols, i.e. polyols, especially diols and triols. Examples of diols are ethane-1,2-diol and propane-1,2-diol; an example of a triol is propane-1,2,3-triol.

[0149] In yet another embodiment, the pH of the low methoxy pectin is 3.0 to 5.5, advantageously 3.6 to 4.7, in particular 3.8 to 4.5. In this pH range, the low methoxy pectin exhibits the greatest chemical stability. Thus, for example, the pH of the low methoxy pectin may also be 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4 or 4.5.

[0150] Uses of Pectin

[0151] In a fourth aspect, the present invention relates to the use of the low methoxyl pectin of the present invention for manufacturing a product, wherein the product is selected from the group consisting of food, medicine, personal care products, household products and consumer products.

[0152] Herein, the food product is preferably selected from jams, marmalades, fruit preparations, jellies, dairy products and beverages.

[0153] In a fifth aspect, the present invention relates to a product comprising a pectin according to the invention. Herein, the product preferably comprises a multivalent cation, the multivalent cation being particularly preferably calcium.

[0154] Such pectin-containing products are preferably selected from foods, pharmaceuticals, personal care products, household products and consumer products.

[0155] In a sixth aspect, the present invention relates to a stable aqueous system, comprising:

[0156] (i) at least one low methoxyl pectin according to the present invention; and

[0157] (ii) at least one multivalent cation.

[0158] In a preferred embodiment the above product or stable aqueous system is characterized in that the multivalent cation is calcium.

[0159] In a further embodiment, the above product or stable aqueous system is characterized in that the total amount of pectin is 0.5 to 1.5 wt. % per dry weight. The total amount of pectin here is preferably 0.8 to 1.4 wt. %, particularly preferably 1.0 to 1.2 wt. % per dry weight.

[0160] Examples of pharmaceutical products in which the low methoxyl pectin of the present invention may be advantageously used include tablets, capsules, wound care products and ostomy products containing pectin in their formulations.

[0161] Examples of cosmetics in which the low-methoxyl pectin of the present invention can be advantageously used include products for cleaning, protecting and caring for the human or animal body containing pectin in their formulations. They also include perfume products and decorative cosmetics.

[0162] Examples of household products in which the low methoxyl pectin of the present invention may be advantageously used include air fresheners, cleaning products, and detergent formulations containing pectin in their formulations.

[0163] definition

[0164] Definitions "Pectin" according to the present application is a plant polysaccharide which (as a polysaccharide uronide) consists essentially of D-galacturonic acid units linked by α-1,4-glycosidic bonds. The galacturonic acid units are partially esterified with methanol. The degree of esterification describes the percentage of carboxyl groups in the galacturonic acid units of pectin which are present in esterified form (e.g. as methyl esters).

[0165] The degree of esterification of "low methoxy pectin" according to the invention is less than 50%. The degree of esterification is the percentage of carboxyl groups in the galacturonic acid chains of pectin that are present in esterified form (e.g. as methyl esters). The degree of esterification can be determined by the method according to JECFA (Topic 19-2016, Joint (FAO / WHO) Expert Committee on Food Additives).

[0166] Definitions "High methoxy pectin" is a pectin with a degree of esterification of at least 50%. On the other hand, low methoxy pectin has a degree of esterification of less than 50%. The degree of esterification is the percentage of carboxyl groups in the galacturonic acid chains of the pectin that are present in esterified form (e.g. as methyl esters). The degree of esterification can be determined by the method according to JECFA (Topic 19-2016, Joint (FAO / WHO) Expert Committee on Food Additives).

[0167] As used herein, the term "high calcium reactive pectin" refers to pectin having a calcium sensitivity greater than 1500 HPE.

[0168] The term "fruit" in the context of the present invention refers to all plant organs that grow from flowers, including typical fruits and fruit vegetables. The term "fruit" in its own place also includes a mixture of fruits of two or more different plants (e.g., apple trees and cherry trees, i.e., plant species), and / or two or more different varieties (e.g., two or more strawberry varieties (e.g., and A similar situation applies to expressions containing the term "fruit", such as "containing fruit" and "fruit preparation".

[0169] "Foodstuff" in the context of the present invention refers to food or feed.

[0170] "Food" comprising more than one composition described herein is referred to herein as "mixed food", wherein the composition comprises at least one low-methoxyl gelling calcium pectinate and ingredients selected from, for example, fruits, vegetables, cocoa, chocolate, nuts and nut fruits and mixtures thereof. Foods of various animal and / or plant origin can serve as the basis for mixed foods. Foods of plant origin include, but are not limited to, milk substitutes.

[0171] "Milk substitutes" refer in particular to products containing water and cereal varieties, pseudo-cereal varieties, legume varieties, nut varieties, almond varieties, nut fruits or mixtures thereof. The term "pseudo-cereals" refers to all cereal fruits (i.e. cereals) of plants that do not belong to the genus Glycyrrhiza. In particular, these are buckwheat, amaranth and quinoa.

[0172] As used herein, "plant-based milk substitutes" refer to products containing, for example, pea, soy, oat, spelt, millet, almond, hazelnut, coconut, cashew, rice, lupine seeds or mixtures thereof. The water contained therein may be derived from the corresponding plant ingredients used and / or may be added during the manufacturing process of the corresponding plant-based milk substitute. In addition, the plant-based milk substitute may contain at least one added sugar and / or sugar substitute.

[0173] The term "sugar" also includes sugar substitutes, in particular sugar alcohols, such as maltitol, sorbitol, mannitol, xylitol, isomalt, lactitol and erythritol, and also inulin, isomaltulose, corn syrup, oligofructose, starch hydrolysates, trehalose and trehalulose.

[0174] It should be explicitly pointed out here that, if necessary, the features of the above solutions or the features of the solutions described in the claims can also be combined so that the described features, effects and advantages can be implemented or achieved in a corresponding cumulative manner.

[0175] All features disclosed in the application documents are regarded as essential to the invention, provided that they are novel compared with the prior art either individually or in combination with each other.

[0176] It should also be explicitly pointed out that in the context of the present patent application, indefinite articles and numerical indications (such as "one", "two", etc.) should generally be understood to mean "at least", that is, as "at least one...", "at least two...", etc., unless this is clearly indicated in the respective context, or it is only obvious or technically necessary for a technician in this field that the meaning there can only be "exactly one...", "exactly two...", etc.

[0177] Further advantages, specific features and advantageous further embodiments of the invention are apparent from the dependent claims and from the presentation of the following examples.

[0178] Example

[0179] 1.1 Test method for determining degree of esterification (DE)

[0180] This method corresponds to the method published by JECFA (Joint FAO / WHO Expert Committee on Food Additives). Unlike the JECFA method, the de-ashed pectin is not dissolved in the cold, but in the presence of heat. Isopropyl alcohol is used as the alcohol instead of ethanol.

[0181] 1.2 Test method for determining calcium sensitivity (CAE)

[0182] Material:

[0183] -320.0 g, 0.65 M potassium acetate-lactic acid buffer (52.50 g potassium acetate, 271.25 g lactic acid, dilute to 5 liters with demineralized water)

[0184] -60.0g sugar (sucrose)

[0185] - 3.12 g pectin (equivalent to 0.82 wt% in the final product)

[0186] -16.0mL calcium chloride solution 5% (m / v)

[0187] Initial weight: about 399g

[0188] Final weight: 380g

[0189] Infusion temperature: about 90℃

[0190] pH: about 3.0

[0191] Dry matter content: about 22%

[0192] Measurement method:

[0193] -Mix pectin and all sugar in a glass bowl.

[0194] -Preheat a hot plate on the highest setting for at least 10 minutes.

[0195] -Place the buffer in a stainless steel saucepan.

[0196] -Sprinkle the pectin-sugar mixture into the buffer solution while stirring and heat to boil while stirring until the calcium pectinate is completely dissolved.

[0197] - Calcium chloride solution is applied and boiled until the final weight is reached.

[0198] - At a temperature of about 90°C, 90 g of boiling material were quickly weighed into three test beakers with tear figures attached and cooled to 20°C in a water bath.

[0199] - Place the beaker in the water bath while avoiding vibration.

[0200] - After exactly 2 hours, the breaking strength is measured using a conventional pectin meter (eg Mark IV, Herbstreith & Fox, Neuenbürg). The results given are the average of three individual values.

[0201] 1.3 Determination of calcium content (complexation method)

[0202] in principle:

[0203] Calcium ions are titrated with Titriplex III (EDTA) at a pH of 12 to 13. Calcium carboxylic acid, which forms a red complex with calcium ions, is used as an indicator. During the titration, free calcium ions react first with EDTA, and then those bound to the indicator react with EDTA, which changes from red to blue in the process.

[0204] Recommended initial weight: Pectin: about 1-2g

[0205] The accurately weighed sample (E) is ashed (2 hours at 550°C in a muffle furnace) and then dissolved in a small excess of dilute nitric acid (heating if necessary). The solution is quantitatively transferred to a 50 mL volumetric flask and filled with demineralized water (warmed in a water bath at 20°C). A sample (a) of this solution containing 3-15 mg of calcium is transferred to a wide-mouthed conical flask and made up to 150 mL with demineralized water. The pH is adjusted to 12-13 with 2n NaOH (check pH) and about 0.1 g of calcium carboxylate indicator is added. The solution is titrated from red to pure blue with 0.025 m Titriplex III solution. The titration must be performed immediately, otherwise precipitation of calcium carbonate may occur due to absorption of CO2 from the air. If the sample solution contains less than 3 mg of calcium, it is recommended to titrate with 0.01 m Titriplex III solution. The consumption of 0.025 m or 0.01 m Titriplex III solution is recorded (b).

[0206] calculate:

[0207] Titration with 0.025 M Titriplex III solution:

[0208] 1 mL of 0.025 m Titriplex III solution corresponds to 1.002 mg of calcium.

[0209]

[0210] Titration with 0.01 M Titriplex III solution:

[0211] 1 mL of 0.01 M Titriplex III solution corresponds to 0.4008 mg of calcium

[0212]

[0213] E: Sample quantity for analysis (ashing), unit: g

[0214] a: Sample solution used for titration, unit: mL

[0215] b: Consumption of 0.025m or 0.01m Titriplex III solution, unit: mL

[0216] f: coefficient of 0.025m or 0.01m Titriplex III solution

[0217] 1.4 Determination of viscosity of 2.5 wt% pectin solution

[0218] Measuring equipment: Physica Rheolab MC 1 / Rheolab QC

[0219] Measuring system: Z2 DIN (disposable measuring cup, reusable measuring cup)

[0220] Sample volume: 100mL

[0221] Sample preparation: The sample prepared by method 1.5 was kept in a 20°C water bath for 15 minutes and then measured.

[0222] Measurement parameters:

[0223] The first stage (determination of viscosity) was set up as follows:

[0224] Default parameters: Shear rate [s -1 ]

[0225] Curve: Ramp Linear

[0226] Value: 0.1 to 500s -1

[0227] Measuring points: 21

[0228] Measuring curve: Constant measuring point duration

[0229] Measuring point duration: about 5.71s

[0230] Section duration: 120s

[0231] Measurement value generation: Automatic

[0232] Temperature: 20℃ (constant)

[0233] Evaluate:

[0234] exist The viscosity is read at a shear rate of [mPas].

[0235] 1.5 Preparation of 2.5% pectin aqueous solution (wt%)

[0236] step:

[0237] Place boiling demineralized water in a 250 ml beaker and sprinkle the sample directly into the stirring vortex while the blender is running. For complete dissolution, run the blender at top speed for approximately 1 minute.

[0238] Prepare a solution of X wt% according to the following formula:

[0239] Sample amount: xg sample, i.e. 2.5g pectin

[0240] Water volume: 100-xg water, i.e. 97.5g water

[0241] 2. Preparation of low methoxyl pectin according to the present invention

[0242] Figure 1 A schematic flow diagram of a method for producing low methoxyl pectin according to the present invention is shown. Starting from citrus dry pomace 10, the pomace is hydrolyzed 20 by incubation in an acidic medium. Here, the pomace is incubated in an aqueous solution at a pH of 1.0 to 3.0 for 2 to 6 hours, during which the original pectin is converted into soluble pectin. Subsequently, the pectin present in the solution is separated from the pomace material by a multi-stage solid-liquid separator 30 (e.g., by a decanter in the first step and a separator in the second step). In step 30, divalent ions are also removed by incubation with a cation exchanger (e.g., Purolite A 100 Plus). Subsequently, in step 50, the pH of the aqueous pectin solution is adjusted, and the aqueous pectin solution is enzymatically treated by adding pectin methylesterase (total activity 1000 to 2500 units / L), and the solution is incubated at 30 to 50° C. for 12 to 18 hours. In step 60, after being below the critical pH limit, the pH is adjusted by raising the pH with a base (e.g., NaOH or KOH). When the desired degree of esterification is reached, the deesterified pectin is precipitated by adding isopropyl alcohol in step 70, and the precipitated pectin is separated from the reaction solution in step 80. Finally, in step 90, the pectin is gently dried by vacuum drying, and then the low methoxy pectin 100 according to the present invention is obtained.

[0243] 3. Use of the low methoxyl pectin described herein for preparing jam

[0244] In one embodiment, citrus pectin according to the invention (designated pectin A) is used as standardized pectin to which a small amount of high methoxyl pectin is added. The composition of the corresponding composition A is as follows:

[0245]

[0246] In another embodiment, apple pectin according to the invention (designated pectin B) is used as standardized pectin. The corresponding composition B has the following composition:

[0247]

[0248] Product formulation of organic jam with composition A (containing pectin A (see table above)), 30° Brix, 55% fruit content:

[0249] formula:

[0250] 240 g of pectin solution containing the above composition A 5% (=1.2%)

[0251] 550g strawberries*, pureed (from organic cultivation)

[0252] 235g sucrose*, crystallized (from organic cultivation)

[0253] 10g lemon juice concentrate*, 45° Brix

[0254] Initial weight: about 1035g

[0255] Final weight: about 1000g

[0256] Dry matter: about 30%

[0257] pH: about 3.3 to 3.5

[0258] Production:

[0259] A: Use a high-speed stirrer to stir and dissolve the pectin in hot softened water at 80°C.

[0260] B: Mix strawberry puree and sucrose and heat to about 90°C.

[0261] C: Add pectin solution "A" and heat to 90°C again.

[0262] D: Add concentrated lemon juice.

[0263] E: Filling temperature is about 80-85℃.

[0264] Product formulation of organic jam with 55% fruit content at 30° Brix containing composition B (containing pectin B (see table above)):

[0265] formula :

[0266] 240 g of pectin solution containing the above composition B 5% (= 1.2%)

[0267] 550g strawberries*, pureed (from organic cultivation)

[0268] 235g sucrose*, crystallized (from organic cultivation)

[0269] 10 g lemon juice concentrate*, 45° Brix

[0270] Initial weight: about 1035g

[0271] Final weight: about 1000g

[0272] Dry matter: about 30%

[0273] pH: about 3.3 to 3.5

[0274] Production :

[0275] A: Use a high-speed stirrer to stir and dissolve the pectin in hot softened water at 80°C.

[0276] B: Mix strawberry puree and sucrose and heat to about 90°C.

[0277] C: Add pectin solution "B" and heat to 90°C again.

[0278] D: Add concentrated lemon juice.

[0279] E: Filling temperature is about 80-85℃.

[0280] 4. Determination of the breaking strength of the product preparations mentioned in point 3

[0281] Test method for determining breaking strength:

[0282] Once the final weight is reached, quickly weigh 100 ± 1 g of each boil sample into a Lüer beaker with a tear-off graphic attached.

[0283] Place the beaker in a water bath set directly near the boiling point (20 ± 1 ° C), avoid vibrations and keep warm. The Lüers beaker must be filled to the level of the gel in the water. When large amounts of sample are placed in or taken out of the water bath, the water level must be adjusted.

[0284] Exactly after 20 hours, the breaking strength was measured with a Herbstreith pectometer Mark III or Mark IV (Herbstreith & Fox GmbH & Co. KG Pektin-Fabriken, Neuenburg, Germany). The result is the average of three individual values.

[0285] result:

[0286] The results are summarized in the following table:

[0287] Pectin dose: 20h breaking strength pH °Brix Pectin A (in the form of composition A) 1.2％ 240HPE 3.34 30.0 Pectin B (in the form of composition B) 1.2％ 320HPE 3.33 30.0

[0288] Even without the addition of external calcium salts, both jams showed high breaking strengths of 240 HPE and 320 HPE, respectively.

[0289] List of reference numerals:

[0290] 10 citrus pulp

[0291] 20 Hydrolysis (decomposition) by incubation in an acidic environment

[0292] 30 Solid-liquid separation and partial deionization

[0293] 40 Concentration and pH Adjustment

[0294] 50 Enzyme

[0295] 60 pH adjustment

[0296] 70 Alcohol precipitation

[0297] 80 Solid-liquid separation

[0298] 90 Dry

[0299] 100 Obtain low methoxyl, high calcium reactive pectin

Claims

1. A method for preparing low methoxyl pectin, the method comprising the steps of: (a) providing a pectin-containing biomass raw material, wherein the pectin-containing biomass raw material comprises an insoluble fiber component and an insoluble protopectin component, and the pectin-containing biomass raw material is obtained from a fruit selected from the group consisting of citrus, apple, sunflower infructescence, rose hip, quince, apricot, cherry, carrot, and a mixture thereof; (b) extracting the pectin-containing biomass material with an aqueous medium having an acidic pH under conditions such that at least a portion of the pectin content is extracted; (c) isolating pectin from the treated biomass feedstock and at least partially removing divalent cations from the pectin extract; (d) concentrating the pectin extract from step (c) so that the content of pectin-containing substances in the pectin extract is 4 to 10% by weight based on dry matter; (e) contacting the concentrated pectin extract from step (d) with pectin methylesterase (EC 3.1.1.11) in aqueous solution at a pH of 3.8 to 4.5, 4 to 10 wt% dry matter and a calcium concentration of less than 0.10 wt%; (f) incubating the aqueous suspension from step (e) to allow pectin methylesterase to deesterify the pectin to produce deesterified pectin; (g) when the degree of esterification of the deesterified pectin is between 10% and 28.0%, the deesterification is terminated, and (h) thereby obtaining a low methoxyl pectin having a calcium sensitivity of 300 HPE to 3000 HPE; in, In step (f), the pH is further adjusted by adding a pH-increasing substance or a mixture of substances.

2. A method for preparing low methoxyl pectin, the method comprising the steps of: (b1) providing a pectin raw material in a dry state, wherein the pectin raw material is obtained from a fruit selected from the group consisting of citrus, apple, sunflower infructescence, rose hip, quince, apricot, cherry, carrot and a mixture thereof; (c1) preparing an aqueous solution of the pectin raw material from step (b1) so that the pectin-containing solution has a pectin-containing substance content of 4-10% by weight based on dry matter; (e) contacting the concentrated pectin-containing solution from step (c1) with pectin methylesterase (EC 3.1.1.11) in aqueous solution at a pH of 3.8 to 4.5, 4 to 10 wt% dry matter and a calcium concentration of less than 0.10 wt%; (f) incubating the aqueous solution from step (e) to allow pectin methylesterase to deesterify the pectin to produce deesterified pectin; (g) when the degree of esterification of the deesterified pectin is between 10% and 28.0%, the deesterification is terminated, and (h) thereby obtaining a low methoxyl pectin having a calcium sensitivity of 300 HPE to 3000 HPE; in, In step (f), the pH is further adjusted by adding a pH-increasing substance or a mixture of substances.

3. The method according to claim 1, characterized in that The pectin-containing biomass raw material is in a moist state, a non-dried state, a frozen state or a dried state.

4. The method according to claim 3, characterized in that The pectin-containing biomass raw material is citrus pomace or apple pomace.

5. The method according to any one of claims 1 or 3 to 4, characterized in that The extraction in step (b) satisfies one or more of the following conditions: i. Use of organic acids; ii. Use of inorganic acids; iii. The pH of the suspension is 0.5 to 4.0; iv. Incubation is carried out at the following temperature: 60°C to 95°C; v. Incubation time is 60 min to 8 h; vi. The dry matter of the suspension is 0.5% to 5%; vii. During the decomposition process, the suspension is set in motion by the application of forces.

6. The method according to claim 5, characterized in that The organic acid is oxalic acid or citric acid.

7. The method according to claim 5, characterized in that The inorganic acid is sulfuric acid, hydrochloric acid, nitric acid or sulfurous acid.

8. The method according to claim 5, characterized in that The pH of the suspension is between 1.0 and 3.

5.

9. The method according to claim 5, characterized in that The pH of the suspension is between 1.0 and 3.

0.

10. The method according to claim 5, characterized in that The incubation is carried out at a temperature between 70°C and 90°C.

11. The method according to claim 5, characterized in that The incubation is carried out at a temperature between 75°C and 85°C.

12. The method according to claim 5, characterized in that The incubation was carried out for a period of 2 h to 6 h.

13. The method according to claim 5, characterized in that The dry matter of the suspension is between 1% and 4%.

14. The method according to claim 5, characterized in that The dry matter of the suspension is between 1.5% and 3%.

15. The method according to claim 5, characterized in that During the decomposition process, the suspension is moved by stirring or shaking.

16. The method according to any one of claims 1 or 3 to 4, characterized in that In step (c), the separation of pectin from the treated biomass feedstock satisfies one or more of the following conditions: i. Separation is carried out in a single stage or in multiple stages; ii. The separation is carried out using a device selected from the following: a decanter, a separator, a wet press, a belt press or a screen; iii. Separation involves the most complete separation of particles possible.

17. The method according to any one of claims 1 or 3 to 4, characterized in that In step (c), the removal of divalent ions from the pectin extract satisfies one or more of the following conditions: i. Using a cation exchanger material, the cation exchanger material is applied in a batch process or a column process; ii. Use of chelating agents to remove divalent ions; iii. Removal of divalent ions is accomplished by precipitation as sparingly soluble salts.

18. The method according to any one of claims 1 to 4, characterized in that The enzymatic deesterification in step (f) satisfies one or more of the following conditions: i. adding at least one pectin methylesterase (EC3.1.1.11) to the aqueous solution; ii. the aqueous solution contains a total activity of pectin methylesterase of 100 to 10,000 units / L; iii. incubation in aqueous solution with at least one pectin methylesterase for a period of 10 to 20 hours; iv. incubating with at least one pectin methylesterase at a temperature of 10 ℃ to 70 ℃; v. The incubation with at least one pectin methylesterase is carried out at an initial pH of 3.8 to 4.5; vi. dry matter in aqueous solution of 5 to 9% by weight; vii. The aqueous solution is put into motion by applying a force during the incubation period.

19. The method according to claim 18, characterized in that The aqueous solution contains a total activity of pectin methylesterase of 500 to 5000 units / L.

20. The method according to claim 18, characterized in that The aqueous solution contains a total activity of pectin methylesterase of 1000 to 2500 units / L.

21. The method according to claim 18, characterized in that The incubation with at least one pectin methylesterase in aqueous solution is carried out for a period of 12 to 18 hours.

22. The method according to claim 18, characterized in that The incubation with the at least one pectin methylesterase is performed at a temperature of 20°C to 60°C.

23. The method according to claim 18, characterized in that The incubation with the at least one pectin methylesterase is carried out at a temperature of 30 to 50°C.

24. The method according to claim 18, characterized in that The incubation with the at least one pectin methylesterase is performed at an initial pH of 4.0 to 4.

3.

25. The method according to claim 18, characterized in that The incubation with the at least one pectin methylesterase is performed at an initial pH of 4.1 to 4.

2.

26. The method according to claim 18, characterized in that The dry matter in the aqueous solution is 6 to 8% by weight.

27. The method according to any one of claims 1 to 4, characterized in that The pH adjustment in step (f) is a stepwise increase in pH by discretely adding a substance or a mixture of substances that increase the pH value.

28. The method according to claim 27, characterized in that The adjustment comprises discrete addition of a substance or mixture of substances which increases the pH value during an incubation time of 1 to 6 hours or when a pH value of 3.5 to 4.5 is reached.

29. The method according to any one of claims 1 to 4, characterized in that The pH value in step (f) is adjusted to maintain the pH value by continuously adding a substance or a mixture of substances that increase the pH value.

30. The method according to any one of claims 1 to 4, characterized in that The substance that increases the pH value is a base.

31. The method according to claim 30, characterized in that The base is present as a mixture of substances in aqueous solution.

32. The method according to claim 30, characterized in that The base is selected from ammonia, sodium hydroxide or potassium hydroxide.

33. The method according to any one of claims 1 to 11, characterized in that The substance that increases the pH value is a weak acid salt or a weak alkaline salt.

34. The method according to claim 33, characterized in that The weakly acidic salt or weakly basic salt is present in the aqueous solution as a substance mixture.

35. The method according to claim 33, characterized in that The weakly acidic salt or weakly basic salt is selected from potassium carbonate, sodium carbonate, sodium bicarbonate and potassium bicarbonate.

36. The method according to any one of claims 1 to 4, characterized in that The substance mixture for increasing the pH value is a weak acidic buffer system or a weak alkaline buffer system.

37. The method according to claim 36, characterized in that The weakly acidic buffer system or the weakly alkaline buffer system is selected from a carbonate / carbonate buffer, an acetic acid / acetate buffer, a phosphate buffer, an ammonia buffer, a HEPES buffer, a PBS buffer and a MES buffer.

38. Low methoxyl pectin obtained by the method according to any one of the preceding claims, characterized in that The esterification degree of the low methoxy pectin is 10 to 28.0%, and the calcium sensitivity of the low methoxy pectin is 300 HPE to 3000 HPE.

39. Use of the low methoxyl pectin according to claim 38 for manufacturing a product, wherein The product is selected from the group consisting of food, pharmaceuticals, personal care products, household products and consumer products.

40. The use according to claim 39, characterized in that The food product is selected from the group consisting of jams, marmalades, fruit preparations, jellies, dairy products and beverages.

41. A product comprising the pectin of claim 38.

42. The product of claim 41, wherein The product comprises multivalent cations.

43. A stable aqueous system, comprising: (i) at least one low methoxyl pectin according to claim 38; as well as (ii) at least one polyvalent cation.

44. The product of claim 42 or the stable aqueous system of claim 43, characterized in that The multivalent cation is calcium.

45. The product of claim 41 or the stable aqueous system of claim 43, characterized in that The total amount of pectin is 0.5 to 1.5 wt% per dry weight.

46. ​​The product or stable aqueous system of claim 45, wherein: The total amount of pectin is 0.8 to 1.4 wt% per dry weight.

47. The product or stable aqueous system of claim 45, wherein: The total amount of pectin is 1.0 to 1.2 wt% per dry weight.

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