CS254326B2 - Method of disaccharides winning from sugar beet and/or mangold heads - Google Patents

Abstract

Process for the recovery of disaccharides from disaccharides containing tuberous plants by mechanically reducing the tuberous plants to a mush, extracting the reduced material with water of less than 60 DEG C, subjecting the extract first to an ultrafiltration and then to a demineralisation and finally concentrating the obtained solution. In the process also mangels having a sugar content of 6-12% by weight can be used as starting material.

Description

The invention relates to a process for obtaining disaccharides from tuberous plants containing disaccharides, in which a solution of disaccharides in water is first ultrafiltered and then deionized.

A process in which disaccharides are obtained from the diffusion juice obtained by extracting beet pulps with hot water at a temperature of 35 to 80 ° ult by ultrafiltration by continuous filtration through a cellophane tube surrounded by other tubes of a fabric resistant to damage and placed in a steel tube. runs under turbulent flow, known from "Warenkennis en Technologie", Vol. 4, pp. 81-87 (1957). In this method, all colloids are held inside the tube without clogging the membrane and are eventually forced out of the tube. The sugar solution, containing all salts, passes in a sterile state through the membrane and is withdrawn through a small opening at the bottom of the steel tube.

The sterile slurry obtained in this way can be completely freed of all salts by means of cation exchangers and anion exchangers to obtain a solution which fully corresponds to the refined juice. This production process yields sugar which does not contain molasses as a by-product. Molasses usually still contains at least 1/6 of the total amount of sugar from diabetes and is a completely inferior product compared to sugar.

Colloidal substances that are taken separately contain proteins, glutamic acid, threonine, proline, and phenylalanine, which are more valuable than molasses.

As far as is known, this known process has not been used anywhere on an industrial scale.

However, as the sugar industry, which focuses on obtaining sugar from diabetes, increasingly threatens rising energy prices and increases labor costs, the following aspects of the known process have been further investigated for possible practical use. Therefore, it was ascertained:

(a) whether a solution to the limited shelf-life of the sugar beet (two to three months) can be found, since, on prolonged storage, the sugar content is reduced;

(b) whether it is more economical to extract sugar from tuber plants, in particular from diabetes;

(c) whether it is possible more effectively to separate the extract from the desired cuttings;

(d) whether impurities can be separated from the sugar solution in such a way that the purification of the sugar by recrystallization from the sugar solutions is not necessary.

Ada) - many years ago, a proposal was made to improve the stability of diabetes in storage, for example by blowing cold air and / or drying the sugar beet pulp and processing it over a period of eight to nine months. However, none of these proposals was a technically and industrially acceptable solution.

Ad b) - according to the established practice, the washed diabetes is cut into small strips or noodles, whereupon the strips are leached with hot water. This stage of the production process is most critical in terms of the amount of sugar loss. In practice, the extraction of sugar with hot water is usually countercurrent. Sugar, which is present in dissolved form in juice in diabetes cells, can only leave cells if the semipermeable membrane plasma is denatured or if the cells open mechanically. If the sugar beet is pulverized into smaller particles, not only sugar is dissolved during hot water extraction, but a number of undesirable substances present in the cells, such as protein, salt, resin, and the like, are released from the disrupted cells. This means for the next production process so many additional complications compared to sugar beet pulp extraction that today it is used exclusively for sugar beet pulp extraction. When cutting diabetes, only some cells are broken, the bulk of the cells remain intact. To extract sugar from intact cells, the cells should be denatured and opened at elevated temperature. Such a change in cell structure is also referred to as plasmolysis. There are several phenomena depending on the temperature used. At 60 ^° C, the protoplasm dies after previous shrinkage, while sudden heating to 70 ° C causes such rapid denaturation that the bulk of the proteins remain in their original state and fixed where they were before.

During the extraction, the juice from the disrupted cells is first washed out, and many colloidal substances are also dissolved. Because during the denaturation of the diabetes proteins, water is released which expels the juice, the juice is also displaced from the interior of the pulp.

The major part of the substances, especially sugar, present in dissolved form in the pulp diffuses from a continuous set of strongly branched channels, which is available for this purpose in the cell tissues of the buffalo cells after their denaturation. For this reason, this extraction process is also called the diffusion process. In the denatured tissue of diabetes, a liquid exchange occurs in which osmotic water enters the tissue through small pores and the sugar solution exits through large pores under the influence of hydrostatic pressure. In doing so, small ions and molecules of compounds other than sugar progress faster into the juice than larger ions and molecules. The cation behavior is also influenced by the size of the anions. To achieve electron neutrality, anions can diffuse only when the diffusion potential is greater than the electrical potential created by charge separation. For example, slower diffusion of larger anions slows down, for example, the rapid transport of alkali metal ions.

In view of the processes occurring during plasmolysis, it is desirable to achieve a warming / cutting temperature as soon as possible. 75 ^{C to} 80 ^C C. ·ιηνse ^r significantly reduce sugar losses _; '' by '' its transformation; induced by the action of microorganisms?

At these high temperatures, cellulose remains almost unchanged in the cellular structure, but pectins swell and eventually decompose as the content of the pectin increases. juice · * · forming extract; · increasing ^j Obťžnost. Processing · this-juice. In addition to ргетёп-у'рекtins-they cause high temperatures' at the same time changes in the structure of cuttings. The compressibility of the cuttings and their compressibility deteriorates and the capillary system of the cell tissue cuts. closing by swelling. The fine channels are constantly changing and more or less closed, so that the extraction of the sugar slows and results in greater losses due to diffusion.

For these reasons, the extraction process is complex and not optimal;

(C) For best separation of the extract from the excluded cuttings, the excluded cuttings are compressed at the end of the process, but with respect to. changes in the cellular tissue of diabetes, as described in paragraph (b), which inhibit the extraction of the still present in the pulp, have not yet been able to achieve optimal separation:

Ad d] - the water used for the extraction should be as pure as possible: In particular, this water should not contain any soluble substances which would be present. may adversely affect the purification process of sugar juice · Especially water containing salts of: alkali metals; is disadvantageous, · _; since these salts inhibit the crystallization of sugar to a large extent and promote undesirable product or molasses.

To achieve optimum particle crystallization of the sugar-průběhu' · further processing raw juice šťávyje played ⁹ to 85 C and / mixed with an excess of slaked -.- vápna-. Present-free acid) form -.- with lime-insoluble salts which -se ^{spolu.s-1-řadow} other impurities. Some of the lime forms calcium monosacarate and dissolves another part. The sludge precipitate is ^ neodfilt-rovatélnáv For this reason * to «juice introduced '*-carbon dioxide gas and water vapor. · -Přitom saccharate is decomposed and forms SPO-ečně- with the dissolved lime insoluble ^5-calcium carbonate it may be separated by filtration.

After double saturation and filtration, a sugar juice is obtained which contains about 15% by weight of the sugar. It is then concentrated under vacuum in a multi-stage process until a saturated solution is obtained, which is then crystallized in the form of a so-called sugar containing about 86% by weight of sugar. In order to obtain a product with a sugar content of almost 100% by weight, it is necessary to separate the confectionery from the mother liquor by centrifugation, after which the described mother liquor process is repeated several times. until: 'molasses-like, unwanted by-product is obtained.

It ^row it found that all the above mentioned drawbacks and problems can be remedied by zpusobemopqdle / -vynálezů. The object of the invention is a way of, obtaining from sugar beet souls and / or: chard,. ,, which is obtained therefrom roztokadisachapidů ₄ ye.vodě prvcvpgdrubí _f. ultrafiltration, and colloidal _{< 5} & gt _; and / or dissolved. The ions are removed and the ion exchanged with the ions is removed. characterized in that the eyeballs of diabetes. _f o. sugar content of <_16 <to - - 19.%. % by weight. </ J / 'or N spinach beet sugar content of about 6 to Д2, ... .-% by weight of mechanically comminuted na.drX, liquid-absent -v .detú sejodsíraní and, drť.- _t is extracted with water at. , do. 18 ° C for 0.5 hours and the extract obtained with a reduced amount. The non-sugar components are subjected to ultrafiltration. dennnGcaldzaci a thickening ..

By crushing the tuberous gh, the crops are mechanically advanced on the set. tqho, qq (_ sugar) present. in pulp, need not be ex-ttahQ-. diffusion as, it was «necessary flushing,. cuttings, but can. its solution, rmechanically / crushed; -cell-tuberous plants rinse, rinse, simply by washing. with water, which _{ιξ I have a} thermoAunsž. 18f'C ...

When used, water with a lower temperature. Than 1 $ ЛС _; The mixture is extracted with at least sugar compounds, by comparison with hot water, water extraction, according to procedure b). For that ?? the reason is. _; possible from the manufacturing process _; several cleansing measures. .

The mechanical-pulverizing of theard can be; for example, by grating, by means of an apparatus <commonly used in potato processing, by means of a centrifugal pump, with an open blower, or by means of vibrating grinders. Preferably, the shredder is used in particular.

After pulverization, the juice and the pulp separate from each other _. be, implemented, much _; more effectively than it was known, because in the course of comminution almost all the cells of the crops are opened and there is no dena cation of the unopened cells at elevated levels. tep ?, lote. Suitable separation procedures are particularly suitable.

a.). use of centrifugal screens with, rotating basket / ve. which; the juice can be washed out of the cells by using a vacuum belt filter,

C.). use of Bowl decanation container with sec spiral.

In the next> production joperacLse. acquired. the solution is subjected to ultrafiltration, in which:. captures all coboid and insoluble compounds (retentate); Prošlá- part: (permeátobsahuje more sodium and «potassium salts than řídká_. Cukerná- juice obtained. Classic procedure, because и classical procedure _of -pod-, substantial portion, and · sodium · potassium. Salt, also gets into molasses While the process of the invention reaches the permeate In order to remove these salts, the permeate must be passed through the ion exchanger.

The comminuted mass is preferably first

25432В separated for the most part from the liquid -Which is contained therein, and then subjected to an extraction with water of at most 10 ^Q C.

Extraction water exposure time is at most half an hour, but such a long time is rarely necessary, since in fact extraction takes place immediately on first contact with water.

In addition, it is very important that the amount of water used for the extraction is chosen in such a way that the solution obtained contains 12 to 14% by weight of sugar.

Another important advantage of the process according to the invention is that the permeate subjected to ultrafiltration, demineralization on the ion exchanger and the concentration is so pure that it is not necessary to carry out the multi-stage crystallization in order to obtain an almost pure beet sugar and finally to obtain the by-product in the form of molasses. Of course, the concentrated solution may be further concentrated and / or cooled to saturation so that the sugar contained in the solution crystallizes, but this operation is not necessary for purification. The production and dispatch of pure concentrated sugar ¹ syrup is also very important for economic reasons, since in practice there are many fields of sugar utilization that are based on concentrated solutions.

A further advantage is that in the process according to the invention it is not necessary to add other non-sugars to induce specific reactions, so that the added substances do not have to be removed again after the respective reactions have been carried out. In fact, the process according to the invention proceeds without the addition of any other reactants.

In addition to the advantages mentioned above, the process according to the invention has another important advantage, namely the possibility of using chard instead of sugar beet as a starting material.

Sugar has been obtained for many decades from sugar beet with a sugar content of 16 to 19% by weight by extracting sugar with water as described above, roughly by separating the desired cuttings and treating the product with lime and carbon dioxide to precipitate pectins and albumins. The precipitated particles are then separated and the resulting thin juice is concentrated by evaporation. The sugar is crystallized from the saturated solution and finally separated.

It has not been considered possible for economic and operational reasons to use chard with a sugar content of 6 to 12% by weight for obtaining sugar. It was assumed that the chard processing would produce significantly more cuttings than the sugar beet processing.

Chard bulbs contain much more sodium and more potassium, less magnesium and less calcium compared to sugar beet. Therefore, the ratio of K + Na to Mg + Ca is much greater than that of diabetes. Detailed information can be found in PJH van Ginneken's 'De onderscheiding van suikerbietenrassen op grond van mineral samenstelling van loof en wortel', published in 'Medelingen van het Institut voor Siukerbietenteelt' Bergen op Zoom, Netherlands, September 1940, and in Part IX - 1939 the same publication.

As already mentioned in describing the known process in (d), the presence of numerous sodium and potassium ions in the sugar-containing extract was a very detrimental phenomenon in the process known to date in terms of process economy.

In addition, the presence of larger amounts of potassium promotes the formation of considerable amounts of molasses.

However, the use of chard for sugar production would have the following advantages:

1. In the case of diabetes, it is necessary and common practice that the customer pays for the delivered eyeballs according to their sugar content, ie they pay for the sugar content. On the other hand, in the case of chard as a starting material, the price could be determined according to the mass quantities of the bulbs delivered. The yield per hectare of chard is much greater than that of sugar beet, so differences in sugar content are no longer important.

2. Using chard as a starting material to obtain beet sugar, the production process in sugar refineries can be smoother, as the shelf life of the chard is at least 7 months, while sugar beet can be stored for two to three months. The sugar factory campaign could thus be extended from the previous three months to about 7 to 10 months.

In this respect, it is important to provide some information on the differences between beet and chard.

Both varieties come from Beta-vulgaris beet. Several varieties have been bred from this original beet over the decades, and the characteristics of these varieties have been streamlined with a view to their end use. There were two more or less contradictory aspects, namely increasing the yield per unit area and increasing the sugar content.

Mangold has the highest yield per unit area of all beet varieties and also the highest sugar yield per unit area, but the sugar content of the eyeballs is low, leaving a significant amount of by-product cuttings. Moreover, the chard is ripe late, so it has a large number of leaves during the harvest season.

These beet varieties use soil moisture much better than other beet species. For this reason, they are more resistant to longer periods of drought. From the same amount of water and nutrients they are able to produce a much larger volume of dry matter than varieties of sugar beet. However, they are not suitable for obtaining sugar by known manufacturing processes, since the amount of pulps per unit weight of beet is considerably greater than when using sugar as the starting material. Also, the cu254326 kr-u content per unit weight of beet is considerably lower.

Sugar beet has a higher sugar content, but yields lower yields per unit area than mangoid. The amount of leaves at the time of harvest is considerably less for sugar beet than for the original Beta-vulgaris beet and also for chard, as the sugar beet ripens early. For obtaining sugar by known methods, diabetes is preferable to chard, since less stiffened cuttings and more sugar are obtained per unit weight of beet.

Example 1

The washed chard is ground on a grater used in the starch industry for potato processing. The grated material, referred to as pulp, is washed with 18 ^° C water in a continuous, multi-step, countercurrent washing process, and then the desired pulp is separated from the liquid. This operation is carried out in a decanter with a fixed bowl and a spiral. The process employs three such decanting devices arranged in series. From the last decanter, the desired pulp, de-sugared and centrifuged to a dry matter content of up to 35% by weight, is taken. The last decanting device is fed with a partially de-sugared pulp from a second decanting vessel which is mixed with water at a temperature of 10 ^° C. The amount of water is minimal because the operation is countercurrent. This amount can be determined by calculation at a certain tolerance for the loss of sugar in the pulp, if it is known that the pulp can be easily centrifuged to a dry matter content of up to 35% by weight in the third stage.

The same operation is repeated three times. Cell juice is obtained from the first decanting device and is used as feed for ultrafiltration.

The first decanter device is fed the grating device mixed with the diluted cell juice from the second decanter device.

The ultrafiltration yields permeate and retentate.

The retentate contains proteins, pectins and resins, which are mixed, for example, with the obtained sugar-free pulp and sold as feed for cattle.

The permeate is further purified by passing through ion exchangers and decolorized with adsorbents.

The thus obtained very pure sugar syrup is suitable for direct human consumption.

Example 2

The grit from the grater of Example 1 is freed of sugar and water by means of a multi-stage countercurrent washing on centrifugal screens.

The sugar-free pulp is then pressed to adjust the water content and thereby reduce the sugar loss to an acceptable level.

The obtained slightly diluted cell juice is then further processed in the same manner as in Example 1.

Example 3

000 kg of chard is pulverized using a grating device used in the starch industry for potato processing. The pulp is then divided into 490 kg of pulp and 900 kg of cell juice directly in the centrifuge. In this process, the pulp is washed with water at a temperature of 9 ° C in a total quantity of 390 kilograms in order to get the pulp free of sugar. The slightly diluted cell juice is then subjected to combined ultrafiltration. Prior to diafiltration, 90 kg of water at 9 ^° C was added to dilute 89 kg of the retentate from the first ultrafiltration and to remove the sugar as much as possible.

The resulting retentate contains only 1% sugar by weight. The purified permeate (filtrate) weighing about 900 kg contains

9.7% by weight of sugar as determined by polarimetry and 13.4% by weight of dry matter.

The invert sugar content is 5.4% by weight of the dry matter.

The purified juice is then demineralized first with a cation exchange resin and then with an anion exchange resin. The purified juice is almost colorless and contains only 5% by weight of non-sugars based on dry weight.

The juice is then concentrated in an evaporator to a concentration of 71% by dry weight. The white sugar obtained by crystallization is of excellent quality and is no worse than other granulated sugars.

Example 4

450 kg of chard are cut into pieces with a maximum size of 8 cm in a cutting device. These pre-cut pieces are conveyed by means of a screw device to a homogenizer, in which they are comminuted to pulp.

This pulp is then treated in the same manner as in Example 3.

Example 5

600 kg of the dough prepared according to Examples 3 or 4 is freed of sugar on a rapidly rotating screen. The separation of sugar is carried out in four stages, with the pulp moving upstream of the juice. In the last step, the pulp is saccharified with 235 kg of water at a temperature of 9 ° C. The liquids separated in the fourth stage of centrifugation are used for the saccharification of the centrifuged pulp from the second stage. This operation is carried out in the third stage. The liquid centrifuged at this stage is passed to the centrifuged pulp from the first stage and the pulp from the third stage is passed to the fourth stage.

Mixture of centrifuged liquids originating in

5 4 3 2 6 ^{sec .} the third stage and the pulp from the first stage are drained of water in the second stage.

The second stage juice is mixed with the undiluted first stage juice. This procedure yields a slightly diluted 520 kg cell juice which is fed to ultrafiltration for the first purification of proteins, resins and pests.

Further processing is carried out as in Example 4. Similarly to the previous examples, a good quality granulated sugar is obtained in this example.

Example 6

The washed sugar beet is pulverized in two hammer mills, which are in series. In the first mill, the beets are crushed to particles with an average size of 1 mm. In the second mill, these beet particles are pulverized to a very fine slurry to open substantially all plant cells and allow juice extraction to be carried out in the next step.

The extraction is carried out in a decanter with a fixed dish and a spiral. In order to reduce the amount of washing water and to suppress sugar losses, the extractors are carried out by a continuous countercurrent four-stage leaching process. Thus, this step comprises the four decanters mentioned above. In the first decanting plant, the freshly ground beet pulp enters the extraction chamber, where it is divided into reconstituted beet juice and sugar-rich pulp. This pulp is mixed with the diluted decantate from the third stage and returns to the second stage. In the second step the decantate is obtained from the mixture, which is mixed with undiluted beet juice.

The pulp from the second stage is mixed with the decantate from the fourth stage and the resulting mixture is returned to the second stage where it is separated into decantate and pulp.

Finally, the pulp from the third stage is directly mixed with a relatively small amount of fresh water at ambient temperature (12 ^C, C). Thus, in the fourth step, the last separation is carried out, yielding beet pulp having an acceptably low sugar content. The resulting pulp is ideally suited as immediate feed for cattle or silage. From each 70t of beet having a sugar content of 16% by weight, 75.3t of beet juice is extracted whose total sugar content, based on the beet, is 15.8% by weight.

The total residence time of the process from the phase at which the beet is still complete until the beet juice is obtained in the manner described above is very short and is 5-10 minutes. Dad's time depends on the 'pipe layout etc.

The next step of the process is the complete removal of colloidal substances and components having a typical diameter of about 20,000 daltorias. In order to reduce sugar loss in the retentate, this process is carried out as a combination of ultrafiltration and dia-ultrafiltration. The apparatus used consists of tubular membranes. From 75.3 t of beet juice, 79.0 t of permeate is obtained with a sugar content of 15.5% by weight based on beet. 7.17 t of fresh water are used for diafiltration. The retentate in an amount of 3.8 t is added to the saccharified pulp intended for use as feed for cattle.

The residence time of the retentate in the filtration step depends on the system chosen, but is at most 10 minutes. This is very important in order to prevent microbial attack of the sugar. The permeate is handled as a sterile stream. The permeate is then purified to an absolutely pure sugar syrup in a deionization unit and concentrated in an evaporator. The final yield of the water-soluble sugar syrup is 15.7 t with a sugar content of 15.27 why, based on beet. The syrup concentration is about 70% by weight.

Example 7 t mixture of cannagold and ^; 1: 1 by weight of sugar beet is processed in the production unit described in Example 6. The sugar beet has a sugar content of 16% by weight and a chard of 12% by weight. The 1: 1 mixture of sugar beet and sugargold contains 14.3% sugar. The purity coefficient (which is defined as the weight ratio of sugar to total dry matter content in the juice) is lower in chard than in sugar beet and is usually 80 to 88%.

The comminution of the mixture in the two hammer mills connected in series is exactly the same as in the case of diabetes alone. Ultra ¹ filtration and diafiltration is easier because chard contains less colloidal substances and juice contains less dry matter. The extent of the deionizer is 15% lower by weight compared to the process of treating the sugar beet itself.

The yield of absolutely purified sugar syrup is 13.9 t.

SUBJECT OF THE INVENTION

Claims (3)

SUBJECT OF THE INVENTION Process for recovering disaccharides from sugar beet and / or chard bulls, wherein the obtained solution of disaccharides in water is first subjected to ultrafiltration and the colloidal and undissolved components are removed, after which the solution is subjected to ion exchange with deinineralization, characterized in that sugar content of 16-19% by weight, and / or chard sugar content from 6 to 12% by weight, mechanically comminuted to pulp, the liquid present in the pulp is removed and the pulp is extracted with water at a rate ture 18 ^C C for a contact time to 0, 5 hours and the resulting aqueous extract with reduced amount of non-sugar constituents was subjected to ultrafiltration, demineralization and concentration. 2. The process according to claim 1, characterized in that water having a temperature of up to 10 DEG C. is used for the extraction ^. 'C. 3. The method according to claim 1, wherein the water extraction is carried out to a sugar content in the water of 12 to 14% by weight.