CH712980A2 - Process for the preparation of pectin from vegetable raw materials. - Google Patents

Abstract

A process for producing pectin from citrus peel, apple pomace, sugar beet pulp or any pectin-containing fruit and vegetable raw material comprises the steps of producing a pectin-containing raw material and carrying out at least one acid hydrolysis and extraction. By separation of the solids, filtration of the extract, removal of calcium ions with ion exchanger and treatment with adsorbent resin, a purified extract is obtained, which is purified by ultrafiltration of extraction acid and low molecular weight substances, concentrated and dried.

Description

Description TECHNICAL AREA

The present invention relates to a process for the preparation of pectin from vegetable raw materials such as fruits or vegetables, in particular from citrus fruits, apple pomace, beet crushing chips and other pectin-containing raw materials such as sugar beets. It further relates to a method for obtaining bio-certifiable pectin.

STATE OF THE ART

The production of pectin from citrus fruits in the prior art is based on the shells. With an area of, for example, 5 km2, with an average yield of 9000 t / km2, around 2000 tonnes of dried skins can be obtained, yielding about 5001 pure pectin with an average pectin content of the skins. This is typically too small an amount to produce the pectin on-site using prior art methods. On-site means in this context at or in the immediate vicinity of the place of cultivation.

WO 00/09 567 shows a process for producing pectin from a vegetable raw material, wherein the raw material is processed to recover an extract by acid hydrolysis. This acidic hydrolysis is carried out by diluting the raw material with water and adding first hydrochloric acid and then phosphoric acid, mixing the mass. The extraction of the pectin is carried out with further addition with mixing at a periodically varying pressure between 1 and 4 Pa. The extract is concentrated, purified and dried.

From EP 0 426 434 A1 (German-language version of the granted patent is published as DE 69 029 365 T2), the use of sugar beet pectins in food products and medicinal products is known, wherein acetic acid has been used in the described method as extraction acid.

From DD 268 857 A1 a method for obtaining pectins is known, in which the acid extraction is also carried out with citric acid. Furthermore, a membrane technique for extract cleaning and drying of the extract is used.

From DD 268 858 A1 a process for the extraction of extractable ingredients from pectin-containing vegetable raw materials is known in which a membrane technique for extract cleaning and drying of the extract is used.

DE 1 224 134 B describes a process for the preparation of pectin extracts or dry pectin.

DE 2 133 572 A1 describes a process for the preparation of pectins and in particular it relates to the production of pectins from citrus peel. It concerns citrus pectin for gelation without sugar and mineral acids are used for extraction.

DE 4 313 549 C1 describes a process for obtaining pectin extract from sugar beets. The beet pectin is obtained without alcohol precipitation, not cleaned but dried.

CH 695 979 A5 describes the production of bio-certifiable pectins by extraction in their own lemon juice with an alcohol precipitation, using organic alcohol.

A classic production requires the addition of mineral acids and precipitation aids according to the prior art, a method which makes it impossible that the obtained pectin can be "certified organic" and which requires complex machines. In addition, experience has shown that not all pectins are readily precipitable.

PRESENTATION OF THE INVENTION

Based on this prior art, the present invention seeks to provide a method that allows even smaller production units to win pectins from a variety of raw materials and cost on site without the use of precipitation aids. Another objective is to circumvent problems related to the precipitability that occur in particular in the case of very highly esterified pectins or sugar beet pectin.

These objects are achieved according to the invention with the method features of claim 1. Such a process for the production of pectin from various pectin-containing raw materials comprises the process steps of producing a raw material containing fruit or vegetable or sugar beet ingredients, carrying out at least one acidic hydrolysis and extracting the pectin at least once, wherein the acid hydrolysis with mineral acids or with organic acids such as citric acid or preferably vinegar. Using bio-certified raw materials and bio-certified organic acid, a bio-certifiable pectin or a bio-certifiable fruit / vegetable extract can be obtained as food, which is particularly interesting for so-called clean label products.

In the method, the vegetable raw materials are first introduced into water, then an acid is added to the vegetable raw materials introduced into water to carry out an acid hydrolysis. The recovery of a solids-free extract is achieved by dilution and separation, after which the extract is purified over ion exchange resin to remove calcium ions. A treatment of the extract over absorber resin leads to discoloration and removal of odors and bitter substances. A multi-stage purification of the extract is carried out by the steps of a first ultrafiltration with membrane separation limits between 3000 daltons and 30,000 daltons to concentrate the extract, a purification of the extract by acid addition to lower the pH to a value at least less than 2.0, preferably from below 1.0, a further concentration of the strongly acidic extract by a second ultrafiltration, a purification of the extract with a third ultrafiltration in diafiltration mode, a concentration of the extract with a fourth ultrafiltration, and a final drying of the concentrated extract achieved.

By separation of the solids, filtration of the extract, removal of calcium ions with ion exchanger and treatment with adsorbent resin, a purified extract is obtained, which is purified by ultrafiltration of extraction acid and low molecular weight substances, concentrated and dried.

With such a method according to the invention, the stated problems and disadvantages are eliminated at the same time. In particular, the fruit / vegetable producer can now utilize locally the fruit and vegetable by-products. Otherwise, the raw materials are crushed, boiled in water with added acid and the pectin dissolved out. The pH of dilute vinegar may be about 3, which is usually considered to be somewhat weak. However, it has been found that over an increased temperature and the time, the yield still interesting developed.

The method according to the invention avoids, following the traditional acid extraction and filtration, the precipitation of the pectins with alcohol from the solution, but recovers the pectins with membrane-technical separation and purification processes and direct drying of the aqueous concentrate. This represents a cost-effective process, since it is possible to work purely aqueous and eliminate the investment in expensive explosion-proof systems.

In the following flow chart according to FIGS. 1A and 1B, the innovative process steps that are central to the method are highlighted. The pectin industry has been working very intensively on membrane separation processes for pectin production, with the focus mostly being on concentrating the pectin extract in order to replace thermal concentration processes.

Especially in the field of cleaning the pectin extracts great progress could be achieved in the present process development by further developed membranes, so that this process is now directly implemented.

In a first ultrafiltration, the extract is concentrated with the aim of reusing as much as possible portions of the extraction acid and thus to obtain an economically, but also an ecologically interesting process.

Particularly important for the purity of the pectin has been found that after the partial concentration by the addition of acid, the pH value is briefly lowered to pH 0.7 to pH 1.6 and then temporally further concentrated. This addition of acid to achieve a pH preferably below 1.0 for a short time has been found to be a key element in achieving sufficient pectin purity.

The strongly acidic permeates of ultrafiltration are separated for purification via a nanofiltration membrane of leached impurities and the permeates of nanofiltration as extraction acid fed back to the extraction process.

If necessary, the deesterification with acids or the amidation can be carried out by the addition of ammonia as an intermediate step of finishing.

By optional repeated re-dilution and concentration over ultrafiltration membranes or by continuous addition of water during ultrafiltration of the pectin extract is further purified by impurities and the added process auxiliaries (so-called diafiltration) and concentrated.

The permeates of the acidic deesterification are also purified by the nanofiltration and recycled the acid in the process. When using ammonia, the permeates are also purified by a separate nanofiltration and recycled the ammonia solution in the process.

Then follow the process steps of drying the concentrate from the ultrafiltration, the grinding of the pure pectins, the mixture, standardization and bottling. Ultrafiltration is a membrane technique in which macromolecular substances and small particles can be separated from a medium and concentrated. If the exclusion limit lies within a range between 2 and 100 nanometers, this is referred to as ultrafiltration.

The method is based on that the extracts are specially cleaned and dried directly without alcohol precipitation.

It is advantageous that bio-certifiable pectin can be obtained with the method. Organic certified pectin means a pectin which is obtained exclusively by processing from organically grown and certified organic natural products and biologically certified extraction acids.

With the method according to the invention Fällbarkeitsprobleme, especially in highly esterified pectins or sugar beet pectin, circumvented by the extract is purified and dried directly after concentration.

In the ultrafiltration steps, the pectin molecules, which are larger than the corresponding membrane separation limit, are retained in the retentate and smaller molecules are allowed to pass into the permeate. As a result, the extract is especially purified by acids and sugars. The ultrafiltration is carried out in several stages.

In the concentration of the extract with the particular fourth and last ultrafiltration Windungsmem-branmodule can be used to achieve a high flow at a sufficient flow. In apple and tri-pectins, pectin levels of about 4% were achieved in this concentrate and about 8% in sugar beet pectins.

Further embodiments are given in the dependent claims.

At the same time, a bio-certifiable pectin is obtained when organically grown raw materials and bio-certified acids such as edible vinegar are used.

The method is particularly suitable for the use of energy at a temperature level of about 100 ° C and is therefore suitable for the use of waste heat or renewable energy.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below with reference to the drawings, which are merely illustrative and not restrictive interpreted. In the drawings show:

1A is a flowchart of an embodiment of a method according to the invention, which is continued in FIG. 1B,

1B is a continuation of the flowchart of FIG. 1A,

2 is a flowchart of the steps of a post-extraction of an embodiment of the invention

process

3 shows a flow chart of the steps of acidic deesterification of an embodiment of the method according to the invention,

4 shows a flow chart of the steps of an amidation of an exemplary embodiment of the method according to the invention, and

5 shows a flow chart of the steps of enzymatic modifications of an embodiment of the method according to the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

Described below is the preparation as a single batch. A production is designed as a batch process for the extraction, followed by a continuous process for the subsequent steps. The process according to the invention has been carried out with various raw materials. In particular, extractions have been carried out with the following seven raw materials: Extraction experiments in Switzerland have, inter alia, been based on lemons, on dried lemon peel, on apple-dried pomace, on sugar beet pulp (fresh, frozen, dried and ensiled). - Raw material 1 (lemons):

In a preceding step whole lemons are used. Advantageously, the steps of oil extraction and of abrasion of the yellow shell parts for color recovery are advantageously preceded by the method according to the invention described here. Subsequently, the lemons of the yellow shell parts are juiced and coarsely crushed, for example with a perforated disc mill that produces strips of about 5 millimeters thick and 1 to 4 centimeters in length. - Raw material 2 (washed and dried lemon peel):

In this embodiment, a commercial lemon peel raw material from South America was used with about 92% dry matter. - Raw material 3 (apple pulp pomace from apple juice processing):

Here, a commercial apple pomace raw material from Europe was used with about 92% dry matter. - Raw material 4 (sugar beet pulp fresh, conventional and organic):

In this embodiment, commercial Rübenpressschnitzel have been used with about 70 to 75% dry matter of Swiss Sugar AG without molasses addition. - Raw material 5 (sugar beet pulp frozen, conventional and organic) Here, commercial beet pulp with about 70 to 75% dry matter of Swiss Zucker AG were freshly frozen without added molasses and used after thawing. - Raw material 6 (sugar beet pulp ensiled):

In this embodiment, commercial Rübenpressschnitzel with about 70 to 75% dry matter of Swiss Sugar AG without added molasses in round bales to about 1200 kg ensiled and used after a few months to a year silage time. - Raw material 7 (dried sugar beet pulp):

Finally, commercially available beet pulp with about 70 to 75% dry matter of the Swiss sugar AG fresh without molasses addition of drying, both at low temperatures and at the operating temperatures. The dried sugar beet pulp have about 92% dry matter.

Described below is the preparation as a single batch for the sugar beet pectin using the raw material 6 with reference to FIG. 1.

For extraction, a heated tank of 1800 liters was used with anchor stirrer. For rapid preheating, 800 liters of softened water 2 in the 1000 l container were preheated to about 70 ° C. via a plate heat exchanger, then pumped into the tank and brought to the nominal temperature of 80 ° C. in the tank.

200 kg of sugar beet pulp silage 1, according to the specified in the table "Typical extraction examples» raw material dry matter content of 60 kg were added and heated again to set temperature of 80 ° C. Subsequently, the amount of acid 3 (6.3 kg nitric acid 60%) necessary to obtain the indicated pH value was added and thus the extraction 5 was started with continuous stirring. After the extraction time of 4 hours, the mash was diluted with 700 liters of softened water or extract of the post-extraction 10 so that the temperature of the diluted mash was 60 ° C to 70 ° C.

After the dilution step 10, the mash was separated via a Flottweg decanter Z23 in a separation step 15. The solids having a dry matter content of 12 to 20% were post-extracted in a solids discharge step 85 and the extract of the post-extraction according to FIG. 2 was recycled to the next extraction for dilution. The extract after decanter was collected in 10001 containers. Partly strong foaming resulted.

The extract after decanter still contained voluminous suspended matter, which could be largely separated via a clarifier.

The extract after Klärseparator was clear filtered over a diatomaceous earth precoat filter with 3 m2 area. It was washed with Clarcel filter aids and during the filtration was a continuous addition of filter aid.

Following the kieselguhr filtration 20, the extract was filtered through Filtrox AF 31H layers, as a safety measure to prevent any leakage of the kieselguhr filter that kieselguhr particles damage the membranes.

The resulting 1700 liters of clearly filtered extract were then passed through an ion exchanger 25 filled with 20 liters of LewatitMonoPlus SP 112 resin, a strongly acidic cation exchanger to remove residual calcium at a flow rate of 400 liters per hour. This resin can be regenerated after loading with a saline solution.

Subsequently, in a decolorization step 30, the extract was passed through a column with 15 liters of Lewatit S 7968 decolorizing resin at a flow rate of 400 liters per hour. This resin binds dyes and odors. The decolorizing resin can be regenerated after loading with sodium hydroxide solution. If the recovery of the adsorbed substances is desired, the column can first be washed out with alcohol and then completely regenerated with sodium hydroxide solution.

The thus purified extract was then further treated via a first UItrafiltrationsschritt 35. Two winding modules of approx. 25 m2 membrane area of type GR61PP-8038/48 from Alfa Laval were used.

In a first part of the ultrafiltration, the extract was concentrated by a factor of 5. Although the remaining acid should be washed out in the subsequent step of diafiltration, it was expedient to increase the acid content first by adding acid 40. The pH value is thereby lowered to <1.0. Then diafiltration is started immediately. At this lower pH, more impurities are separated from the pectin molecule and washed out.

After concentration by a factor of 5, an acid addition 40 of 3.5 kg of nitric acid 60% followed by a further concentration by a second ultrafiltration 45 to about factor 7.5.

By continuous addition of water with simultaneous ultrafiltration, the concentration was maintained and the concentrated extract was purified by diafiltration 50 (also ultrafiltration 3) with a total of 1500 liters of softened water or reverse osmosis water and the acid washed out. The leaching was monitored by measuring the conductivity of the permeate.

At the end of the diafiltration 55 was concentrated by a fourth ultrafiltration 55 as much as possible. The final concentration was factor 16 based on the clarified extract and had 7.4% dry matter.

In the drawings, the fourth ultrafiltration 55 is shown as the last step in the flow chart of Fig. 1A, and the method according to the embodiment will be further described with the next steps in the flow chart of Fig. 1B.

The concentrate 60 was applied at 50 ° C for drying on a belt dryer for a drying step 65. The evaporation of water took place in about 5 minutes by heating the heat-permeable tape on the lower

Side with hot water of 95 ° C and air overflow of the thin pectin film on the upper side. The dried pectin could be removed from the belt with scrapers and was then fed to the grinding.

The grinding in a grinding step 70 was carried out by pre-crushing with a Rotoplex granulator Ro28 / 40 from Alpine, followed by the fine grinding with a fine impact mill 160 UPZ Alpine. The spectrum of the particle size distribution thus corresponded approximately to that of commercially available pectins. There were obtained 12.2% sugar beet pectin based on the raw material dry matter used.

Depending on the application, the pectins were then mixed to homogenize a batch 75 or by addition of sugar or other Rezepturzutaten such. Buffer salts standardized 75 and bottled 80.

For the production of citrus pectin using the raw materials 2, with respect to the process steps as such, the same process is applied with the above-described procedure for the sugar beet pectin with the following modifications: 900 liters of water suppositories have been used. It has been used 35kg of dried citrus peels, which correspond to 32.2 kg of dry matter as raw material. The addition of acid was 4.0 kg of nitric acid 60%. The extraction time is 2 hours at 80 ° C. The dilution was done with 700 liters of water. Concentration with the first ultrafiltration 35 was by a factor of 3. The following acid addition 40 comprised 2.5 kg of 60% nitric acid. The further concentration through the second ultrafiltration 45 occurred at about factor 4. The diafiltration 50 was carried out with a total amount of 1000 liters of softened water. The fourth ultrafiltration 55 with a final concentration of the factor 12 occurred with 3.4% dry mass in the concentrate. After grinding, 7014.9% and 16.7% citrus pectin were obtained.

In the embodiments with respect to sugar beet pectin, apple pectin or citrus pectin, the following parameters for the raw materials 2, 3 and 6 have resulted:

The analysis of the result of the application of the method in the raw material 2 gave the following qualities of citrus pectins:

The analysis of the result of the application of the method in raw material 6 gave the following quality of sugar beet pectin:

The sugar beet pectin L had a very good ability to stabilize oil emulsions.

FIG. 2 shows the post-extraction 95, which then leads again to the dilution step 10. This post-extraction is carried out based on the permeates obtained in the ultrafiltration 35, 45, 50 process, which are fed to a nanofiltration 90, whereby a pure dilute acid is obtained in the permeate, which in turn can be fed to the extraction 5. As a result, about 2/3 of the acid can be recirculated without undesirable concentration of small-molecule impurities. In particular, the retentates of the nanofiltration 90 can then be used to obtain low molecular weight compounds, such as e.g. Sugar, galacturonic acid oligomers and other substances are used.

Fig. 3 shows the additional process steps of acid deesterification, which is optionally switched on between the first and second ultrafiltration. In this case, a simple modification of pectin is achieved to Niederverestertem pectin, in which not first dry pectin is redissolved or processed in alcoholic suspension, but the extract after concentration with the first ultrafiltration 35 is treated with mineral acid 110, that an acid concentration of 0.1 to 0.6 Mol / liter ideally about 400 mmol acid / liter is achieved and stirred at 25 to 35 ° C for several hours / days until the desired degree of esterification is achieved. Subsequently, the extract is further processed according to the standard process via the second ultrafiltration 45.

Fig. 4 shows the additional process steps of an amidation, which can be used between first and fourth ultrafiltration 35 and 55, respectively. In this case, a simple modification of pectin to amidated pectin is achieved in which dry precipitate is not first dissolved or processed in alcoholic suspension, but the extract after concentration with the first ultrafiltration 35 cooled to a temperature of minus 2 ° C to 10 ° C. 115 and with ammonia 120 is added that an ammonia concentration of 0.1 to 3 mol / liter is achieved and stirred at -2 to +15 ° C for several hours until the desired Amidierungsgrades reached. Subsequently, the extract is further processed via a fifth ultrafiltration 125 and a diafiltration 130, concentrated with the ultrafiltration 55 and finally dried.

It can be attributed to the amidation with a nanofiltration 134 permeate.

Finally, FIG. 5 shows process steps for an enzymatic modification of pectin, in which dry particulate need not first be redissolved, but the completely purified extract after concentration via the fourth ultrafiltration 55 is mixed directly with the enzyme 140 corresponding to the desired product and kept at 20 to 40 ° C and stirred. After reaching the desired pectin, the enzyme is inactivated by pasteurization 145 at 70 to 95 ° C, preferably 80 ° C for 30 seconds to 3 minutes, preferably 1 minute, the enzyme. If necessary, thermally concentrated 60 and the extract is dried 65.

Thus, low-esterified pectins, galacturonic acid oligomers, monogalacturonic acid or pH and molecular weight-modified pectins can be obtained simply and inexpensively.

LIST OF REFERENCE NUMBERS

1 vegetable raw material 2 water 3 acid 5 hydrolysis extraction 10 dilution 15 separation 20 filtration 25 ion exchanger 30 decolorization 35 first ultrafiltration 40 acid addition 45 second ultrafiltration 50 third ultrafiltration / diafiltration 55 fourth ultrafiltration 60 thermal concentration 65 drying 70 grinding

Claims (22)

75 Mixing and standardization 80 Filling of the final product 85 Solids discharge 90 Nanofiltration with permeate recycling for extraction 95 Post-extraction 100 Separation 105 Despectinized raw material 110 Acid addition Deesterification 115 Cooling 120 Amidation reaction 125 Fifth ultrafiltration 130 Sixth ultrafiltration 135 Nanofiltration with permeate recycling for amidation 140 Enzyme addition 145 Pasteurization Claims 1. A process for the preparation of pectin from vegetable raw materials such as fruits or vegetables, in particular from citrus fruits, apple pomace, beet pulp and other pectin-containing raw materials such as sugar beets, without the use of precipitation aids with the process steps: - introduction of the vegetable raw material (1) in water ( 2), - supplying an acid (3) to the vegetable raw materials introduced into water, - carrying out an acidic hydrolysis (5), - obtaining a solids-free extract by dilution (10) and separation (15), - stepwise purification of the extract by the steps: - a first ultrafiltration to concentrate (35) the extract, - a purification of the extract by acid addition (40) to lower the pH to a value at least less than 2.0, preferably from below 1.0, - a purification of the extract with a third ultrafiltration in diafiltration mode (50), and - final drying of the concentrate Extract (65). 2. The method of claim 1, wherein the step of purifying the extract by acid addition (40) over a short period of 1 to 10 minutes. 3. The method of claim 1 or 2, wherein in the step of introducing the vegetable raw material into water (2) this water may also comprise an acidic permeate from a nanofiltration (90), which is carried out after one of the ultrafiltration for permeate recirculation. 4. The method of claim 3, wherein the mixture of water (2) or permeate from the nanofiltration (90) between 50 and 70 "Celsius and then heated to preferably 90" Celsius, so that this mixture before the hydrolysis (5 ) between 70 to 100 "Celsius, advantageously 80" Celsius and more. 5. The method according to any one of claims 1 to 4, wherein the acidic hydrolysis (5) is carried out optionally with a mineral acid or with an edible acid and the temperature reached in the preceding step is maintained between 2 and 4 hours. 6. The method according to any one of claims 1 to 5, wherein the recovery of a solids-free extract by dilution (10) and separation (15) with a decanter and Klärseparator and subsequent filtration (20) is preferably achieved via a Anschwemmfilter. 7. The method according to any one of claims 1 to 6, wherein interposed between the recovery of the solids-free extract and the stepwise purification, one and / or the other of the following steps: - Purification of the extract over ion exchange resin (25) to remove Calcium ions, and / or - treatment of the extract via absorber resin (30) for decolorization and removal of odor and bitter substances. 8. The method according to any one of claims 1 to 7, wherein prior to the purification of the extract with a third ultrafiltration in Diafiltrationsmodus (50) the step - a further concentration of the strongly acidic extract by a second ultrafiltration (45) is connected upstream, and / or after the extraction of the extract has been followed by a third ultrafiltration in the diafiltration mode (50), the step of concentrating the extract is followed by a fourth ultrafiltration (55). A process according to claim 8, wherein in concentrating the extract with the fourth ultrafiltration (55) for wound membrane modules, a larger spacer of e.g. 90 mil is used to achieve a sufficient overflow at high viscosity. A process according to any one of claims 1 to 9, wherein any of the ultrafiltrations employs membrane separation limits between 3000 daltons and 30,000 daltons. A process according to any one of claims 1 to 10, wherein the third ultrafiltration in diafiltration mode (50) comprises recovery of the added acid via nanofiltration (90) in the initial phase of diafiltration and rejection of permeate at advanced dilution. 12. The method according to any one of claims 1 to 11, wherein the third ultrafiltration is followed by a conductivity measurement, wherein in the retentate and permeate the conductivity of the added diafiltration water is sought. 13. The method according to any one of claims 1 to 12, wherein prior to drying (65), the concentrated extract is again thermally concentrated (60). 14. The method according to any one of claims 1 to 13, wherein the concentrated extract is dried on a belt dryer atmospheric at large overflow with conditioned air and about 90 ° C heating in a few minutes (65). The method of claim 14, wherein said drying is followed by a one-step or multi-step milling step (70). 16. The method according to any one of claims 1 to 13, wherein the concentrated extract is dried by spray drying, in which case the step of grinding (70) is omitted. 17. The method of claim 3, wherein the permeates obtained in the steps of the ultrafiltrations (35, 45, 50) are fed to a nanofiltration (90), whereby a pure dilute acid is obtained in the permeate, which in turn is fed to the extraction (5) , A process according to any one of claims 1 to 17, wherein water is added to the solid (85) recovered by the separation (15) after the step of acid hydrolysis (5) and subjected to a second extraction step, a post-extraction (95) becomes. A process according to any one of claims 1 to 18, wherein the adsorbent resin loaded after the decolorization step (30) regenerates and the substances thus obtained, e.g. Phenols are purified. 20. The method according to any one of claims 1 to 19, wherein for the production of low-esterified pectin, in which not first dry pectin is redissolved or processed in alcoholic suspension, but the extract is added after concentration with the first ultrafiltration (35) with mineral acid, that an acid concentration of 0.1 to 0.6 mol / liter ideally about 400 mmol acid / liter is achieved and at 25 to 35 ° C for several hours / days until the desired degree of esterification is reached, then the extract according to the standard process on the second ultrafiltration (45) is further processed. 21. The method according to any one of claims 1 to 20, wherein to a simple modification of the pectin to be obtained in amidated pectin to be recovered, in which not first dry pectin is redissolved or processed in alcoholic suspension, but the extract after concentration with the first ultrafiltration (35) cooled to a temperature of minus 2 ° C to 10 ° C and mixed with ammonia, wherein an ammonia concentration of 0.1 to 3 mol / liter is achieved and at -2 to +15 ° C for several hours to reach the desired degree of amidation is stirred, wherein subsequently the extract is further processed via a fifth and / or sixth ultrafiltration (125, 130) and finally dried. 22. The method according to any one of claims 1 to 21, wherein to achieve a simple enzymatic modification of pectin to be obtained directly after the concentration of the completely purified extract after the fourth ultrafiltration (55) with the enzyme corresponding to the desired product and 20 to Is kept at 40 ° C and stirred and wherein after reaching the desired pectin by pasteurization (145) at 70 to 95 ° C, preferably 80 ° C, for 30 seconds to 3 minutes, preferably 1 minute, the enzyme is inactivated.