CS270903B1 - Method of starch solutions hydrolysis - Google Patents

Abstract

This solution relates to a method of starch solutions hydrolysis, particularly for the use in the food-stuff industry. The starch solutions hydrolysis rests in the fact that 20 up to 40 parts of the starch solutions and 27 to 35 in mass % of solids get in contact with 3.2 up to 5.4 parts of a strong acidic polymerous cation resin in a temperature of 85 to 120 degrees Celsius selected from a group of styrene and alkyl methacrylate copolymers containing 1 to 20 in mass % of an reticulation agent selected from a group of divinylbenzene and ethylene dimethacrylate. Due to a slower course by comparison with the mineral acids catalysis, the reaction under the ionex catalysis is more selective from the point of view of the glucose creation and, particularly, the product is absolutely clear (colourless). Another benefit is the easy removal of the catalyst from the reaction mix, without the necessity of neutralisation and introduction of salt into the product. The selectivity of the glucose creation can be achieved by selecting a reticulation rate of polymer catalyst.

Description

(57) The solution concerns a process for the hydrolysis of starch solutions, in particular for use in the food industry. A method for hydrolyzing starch solutions is to contact 20 to 40 parts of starch solutions with 27 to 35% by weight solids at a temperature of 35 to 120 ° C with 3.2 to 5.4 parts of a 9-acid polymeric cation exchange resin selected from the group of styrene-alkyl methacrylate copolymers containing from 1 to 20% by weight of a sulfide selected from the group consisting of divinylbenzene and ethylenedimethacrylate. Due to the slower course compared to mineral acid catalysis, the ion exchange reaction is more selective for the formation of glucose and, above all, the product is completely colorless. Another benefit is the easy removal of the catalyst from the reaction mixture without the need for neutralization and introduction of salts into the product. The selectivity of glucose formation can be controlled by selecting the degree of crosslinking of the polymer catalyst.

CS 270 903 Bl

The invention relates to starch hydrolysis solutions, in particular for use in the food industry.

The present state of the process for the hydrolysis of liquefied starch has been found by computer search in the Chemical Abstracts and World Patent Index (WPI) from 1960 to 1985. In practice, hydrolysis catalysed by mineral acids or enzymes is used. Hydrolysis with mineral acids proceeds fast enough, but provides a dark product which is difficult to purify (glucose thus prepared is not suitable for medical purposes) and additionally contains salts which are the product of catalyst neutralization. Enzyme hydrolysis provides a pure product, but is economically more demanding and dependent on the source of the enzymes. Catalysis with other substances (benzenesulfonic acid, ethanesulfonic acid, 1-dodecylbenzene-,

2-sulfonic acids) having similar disadvantages as mineral acids, moreover, they are more difficult to obtain and their use lies in the theoretical field. These drawbacks are overcome by the method of hydrolysis of starch solutions according to the invention, which comprises contacting 20 to 40 parts of starch solutions of β 27 to 35% by weight with dry matter at a temperature of 85 to 120 ° C with 3.2 to 5.4 parts of a strongly acidic polymeric cation exchanger selected from the group of copolymers of styrone and alkyl methacrylates containing 1 to 20 wt.%, a crosslinker selected from the group consisting of divinylbenzane and ethylene dimethacrylate.

Due to the slower course compared to mineral acid catalysis, the ion exchange catalysis reaction is more selective for the formation of glucose and, in particular, the product is completely colorless. Another benefit is the easy removal of the catalyst from the reaction mixture without the need for neutralization and introduction of salt into the product. The selectivity of glucose formation can be controlled by selecting the degree of crosslinking of the polymer catalyst.

Sulfo groups bonded to both styrene-divinylbenzene and methacrylate polymer matrices having a crosslinker content of 1 to 20 may be advantageously used as catalysts. % of crosslinker). I ion exchange activity is dependent on the degree of ion exchange crosslinking. Gel types of ion exchangers with a crosslinker content of 1 to 10% are more active than the macroporous type with 20% crosslinker. This is mainly due to the fact that the active functional groups of the catalyst are available to the substrate to varying degrees to exclude the accessibility of higher oligosaccharides to the ion exchange polymer matrix. As a result, the concentration of the individual hydrolysis products is reduced and the reaction runs entirely in favor of the end product. ,

The actual reaction conditions can be determined by a substrate concentration of 25 to 35% by weight, and a reaction temperature of 70 to 120 ° C.

The hydrolysis of starch solutions according to the invention can be carried out regardless of the origin of the starch used and the reaction conditions.

The examples described herein fully characterize the invention without limiting its scope in any way.

Example 1 * parts of liquefied potato starch (27% dry matter, DE 24.42) was charged to a 85 ° C tempered reactor and 5.36 parts of strongly acidic ion exchange resin in H-form were added (group contents 4.9-5.1) mmol / g, 76 to 85% water, particle size 0.315 to 1.25 mm) based on styrene-divinylbenzene copolymer and 2% crosslinker. The reaction mixture was stirred with a propeller stirrer for 31 hours. The product contained 83.24 wt. % glucose, 14.17 wt. % maltose and 2.57% higher oligodextrins, the glucose equivalent was 66.2. The product was completely colorless.

CS 270 903 B1

Example 2 parts of liquefied potato starch according to example 1, containing 1.84 wt. % glucose, 10.29 wt. % maltose and 87.87 wt. % of higher oligodextrins were hydrolyzed at 85 ° C with 3.22 parts of wet strong acid ion exchanger 8 with a content of groups 4.9 to 5.1 mmol / g, a water content of 63 to 73% of a grain size of 0.315 to 1.25 mm based on ethylene- divinylbenzene copolymer with 4 wt.%, crosslinker. After 52 hours of stirring, the reaction mixture contained 75.83 wt%, glucose, 7.33 wt%, maltose and 16.84 wt%, higher oligodextrins, with a glucose equivalent of 75.0%. The product was completely colorless.

Example 3 parts of enzymatically liquefied cereal starch (35.2% by weight, dry matter and with a glucose equivalent of 30.0%) were hydrolyzed at 100 ° C by treatment with 3 parts of methacrylate ion exchanger containing sulfo groups at a concentration of 1 mmol / g. After 46 hours, the reaction mixture contained 80 wt.%, Glucose, 13.4 wt.%, Maltose and 6.6 wt.%, Higher oligodextrins, with a glucose equivalent of 66.2%.

Example 4 parts of liquefied potato starch in 24% by weight, the dry matter was hydrolyzed at 120 ° C, and part of strongly acid cation exchange resin 20% by weight, technical divinylbenzene After 24 hours, the reaction mixture contained 73% by weight, glucose, 8.5% by weight, maltose and 17.5 wt.%, Oligodextrin. The glucose equivalent was 73%. Glucose equivalent (DE) is given in% but is dimensionless.

Claims (1)

SUBJECT OF THE INVENTION A process for the hydrolysis of starch solutions, characterized in that 20 to 40 parts of starch solutions □ 27 to 35% by weight of solids are contacted at a temperature of 85 to 120 ° C with 3.2 to 5.4 parts of a strongly acidic polymeric cation exchanger selected from a group of styrene-alkyl methacrylate copolymers containing 1 to 20% by weight of a crosslinking agent selected from the group consisting of divinylbenzene and ethylene dimethacrylate.