CN110938713A

CN110938713A - Refining process of crystalline glucose

Info

Publication number: CN110938713A
Application number: CN201911240809.0A
Authority: CN
Inventors: 赵兰坤; 张宗鑫; 刘永国; 曹昌岭
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-08-22
Filing date: 2019-12-06
Publication date: 2020-03-31

Abstract

The invention belongs to the field of sugar separation and purification, and discloses a refining process of crystalline glucose, which comprises the following steps: step 1) deactivating enzyme and removing slag, step 2) decolorizing active carbon, step 3) crystallizing in a crystallizing tank, step 4) nano-filtering, and step 5) cooling, filtering and drying. The invention has simple process and low cost, and the prepared product reaches the pharmaceutical grade.

Description

Refining process of crystalline glucose

Technical Field

The invention belongs to the field of sugar separation and purification, and particularly relates to a refining process of crystalline glucose.

Background

Glucose (Glucose) (chemical formula C)₆H₁₂O₆) Also called corn glucose and corn sugar, and is called glucose for short. English is another name: dextrose, Cornsugar, Grapesugar, Bloodsugar, is the most widely distributed and important monosaccharide in natureIt is a polyhydroxyaldehyde. Pure glucose is colorless crystals, has sweetness less than sucrose (no sweetness is usually tasted by people), is easily soluble in water, is slightly soluble in ethanol, and is insoluble in diethyl ether. The aqueous solution is optically active to the right and thus belongs to the term "dextrose". Glucose plays an important role in the field of biology, and is an energy source and a metabolic intermediate product of living cells, namely a main energy supply substance of organisms. Plants can produce glucose through photosynthesis. Has wide application in the candy manufacturing industry and the medicine field.

Corn starch is an important raw material for extracting glucose, corn starch molecules are formed by connecting thousands of glucose units, the process for extracting glucose from starch saccharification liquid is the last step of process for extracting glucose from corn starch milk, and the process is also related to the quality of a finished glucose product. In order to reduce the by-product of glucose, various solutions are proposed in the glucose processing steps, and the more common processes are: the existing production process for producing glucose comprises the following steps: taking starch as a raw material, liquefying under the action of liquefying enzyme after size mixing, saccharifying under the action of saccharifying enzyme to finally form glucose syrup with DX about 95%, filtering in a plate frame or rotary drum by adopting a diatomite filtering mode to remove residual starch and suspended matters, removing salt in sugar solution by adopting a fixed bed ion exchange process mainly by utilizing a large amount of cation and anion exchange resin, and finally obtaining medical grade glucose by using a recrystallization process; however, the process has the defects of high wastewater yield, large investment and land occupation, large quantity of operators, low working efficiency, low process yield and the like. At present, most of the existing glucose production technologies have the defects of complex process, high cost and the like; the development of a low-cost process for refining crystalline glucose is a technical problem to be solved.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a refining process of crystalline glucose.

In order to achieve the purpose, the invention is realized by the following technical scheme:

a process for refining crystalline glucose, comprising the steps of: step 1) deactivating enzyme and removing slag, step 2) decolorizing active carbon, step 3) crystallizing in a crystallizing tank, step 4) nano-filtering, and step 5) cooling, filtering and drying.

In particular, the amount of the solvent to be used,

the step 1) of enzyme deactivation and slag removal comprises the following steps: inactivating enzyme of starch saccharification liquid, removing residue with filter, and collecting filtrate.

In particular, the amount of the solvent to be used,

the step 2) of activated carbon decolorization comprises the following steps: adding 1% by weight of active carbon into the filtrate, decolorizing for 30min, filtering to remove the active carbon, and then feeding into a crystallizing tank.

In particular, the amount of the solvent to be used,

the step 3) of crystallizing in a crystallizing tank comprises the following steps: the seed is reserved in the crystallizing tank by 25 percent, the temperature of the mixed liquid of the saccharified liquid and the seed crystal is more than or equal to 48 ℃ when the crystallizing tank is full,

the total crystallization time is 60 hours, and the crystal growth time is 12 hours; cooling and crystallizing for 48 hours by adopting a cooling water cooling method, wherein the sugar temperature is reduced from 46 ℃ to 35 ℃ in a first stage of 28 hours, and the temperature is reduced to be less than or equal to 0.4 ℃ per hour;

the second period is 20 hours, the sugar temperature is reduced from 35 ℃ to 22 ℃, and the temperature is reduced to be less than or equal to 0.65 ℃ per hour; the temperature difference between the cooling water temperature and the sugar temperature of the interlayer of the crystallization tank is less than or equal to 15 ℃; the stirring speed of the crystallizing tank is 3min/360 degrees; and (4) collecting the crystals.

In particular, the amount of the solvent to be used,

the step 4) of nanofiltration comprises the following steps: adding purified water into the crystals, and heating to 40 ℃ to obtain a glucose saturated solution; then the filtrate enters a nanofiltration membrane for filtration, and the filtrate is collected.

In particular, the amount of the solvent to be used,

the step 5) of cooling, filtering and drying comprises the following steps: cooling the filtrate to 7 deg.C, maintaining the temperature for 2 hr, filtering, collecting filtrate and precipitate, recrystallizing the filtrate in a crystallizer, and vacuum drying the precipitate at 45 deg.C to obtain glucose crystal.

Preferably, the first and second electrodes are formed of a metal,

the molecular weight cut-off of the nanofiltration membrane is 300 Da.

Compared with the prior art, the invention has the advantages that the following aspects are mainly included but not limited:

the production process is simple and feasible, the steps of ion exchange, microfiltration and the like are reduced, and the cost of an enterprise is saved; the mode of crystallization, nanofiltration and natural crystal precipitation of saturated solution is adopted, so that the industrial energy consumption is reduced, the burden of a nanofiltration system is reduced, and the cost is saved; by adjusting crystallization conditions and parameters, the prepared product has better performance parameters in all aspects; the crystalline glucose prepared by the invention has better performance in all aspects, is crystalline particles, is soft and sweet, has no abnormal taste, and has the purity of 99.8 percent, the chloride content of 0.001 percent and the sulfuric acid ash content of 0.05 percent; heavy metals were not detected to be present.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present application, the present invention will be described more clearly and completely below with reference to specific embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A process for refining crystalline glucose, comprising the steps of:

preparing starch saccharification liquid (the sugar degree is 18%) by using a corn amylase method, deactivating enzyme, removing residues by using a filter, collecting filtrate, adding 1% by weight of active carbon into the filtrate, decoloring for 30min, filtering to remove the active carbon, adjusting the concentration of the liquid to 72%, adjusting the temperature to 60 ℃, adjusting the pH value to 3.8 and the like to reach indexes, and directly feeding the indexes into a crystallization tank;

the seed is reserved in the crystallizing tank by 25 percent, and the temperature of the mixed liquid of the saccharified liquid and the seed crystal is more than or equal to 48 ℃ when the crystallizing tank is full.

the second period is 20 hours, the sugar temperature is reduced from 35 ℃ to 22 ℃, and the temperature is reduced to be less than or equal to 0.65 ℃ per hour; the temperature difference between the cooling water temperature and the sugar temperature of the interlayer of the crystallization tank is less than or equal to 15 ℃;

the stirring speed of the crystallizing tank is 3min/360 degrees; the crystallization tank and the discharge system are sealed devices, and the interior of the container is kept in a positive pressure state by sterile compressed air; the crystallization yield massecuite dry basis/wet massecuite dry basis is 58%;

collecting crystals; adding purified water into the crystals, and heating to 40 ℃ to obtain a glucose saturated solution; then the mixture enters a nanofiltration membrane (the molecular weight cutoff is 300 Da) for filtration;

cooling the filtrate to 7 deg.C, maintaining the temperature for 2 hr, filtering, collecting filtrate and precipitate, recrystallizing the filtrate in the above crystallizer, and vacuum drying the precipitate at 45 deg.C to obtain glucose crystal.

Example 2

A process for refining crystalline glucose, comprising the steps of:

preparing starch saccharification liquid (the sugar degree is 20%) by using a corn amylase method, deactivating enzyme, removing residues by using a filter, collecting filtrate, adding 1% by weight of active carbon into the filtrate, decoloring for 30min, filtering to remove the active carbon, adjusting the concentration of the liquid to 74%, the temperature to 60 ℃, the pH value to 4.2 and the like to reach indexes, and directly feeding the liquid into a crystallization tank;

the seed is reserved in the crystallizing tank by 30 percent, and the temperature of the mixed liquid of the saccharified liquid and the seed crystal is more than or equal to 48 ℃ when the crystallizing tank is full.

the stirring speed of the crystallizing tank is 3min/360 degrees; the crystallization tank and the discharge system are sealed devices, and the interior of the container is kept in a positive pressure state by sterile compressed air;

Example 3

The quality of the product of the invention (taking example 1 as an example) is tested as follows:

dextrose monohydrate: the molecular formula is C6H12O6.H2O, the molecular weight is 198.17;

the state is as follows: crystalline particles, free of macroscopic impurities;

color: white;

and (3) taste: soft and sweet taste without abnormal taste;

purity of glucose: 99.8 percent;

pH：5.7；

chloride content: 0.001 percent;

ash content of sulfuric acid: 0.06 percent;

heavy metals: - - -.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A process for refining crystalline glucose, comprising the steps of: step 1) deactivating enzyme and removing slag, step 2) decolorizing active carbon, step 3) crystallizing in a crystallizing tank, step 4) nano-filtering, and step 5) cooling, filtering and drying.

2. The refining process of claim 1, wherein the step 1) of deactivating enzymes and removing slag comprises the steps of: inactivating enzyme of starch saccharification liquid, removing residue with filter, and collecting filtrate.

3. The refining process of claim 2, wherein the step 2) of decolorizing the activated carbon comprises the steps of: adding 1% by weight of active carbon into the filtrate, decolorizing for 30min, filtering to remove the active carbon, and then feeding into a crystallizing tank.

4. The refining process of claim 3, wherein the step 3) of crystallizing in a crystallizing tank comprises the steps of: the seed is reserved in the crystallizing tank by 25 percent, the temperature of the mixed liquid of the saccharified liquid and the seed crystal is more than or equal to 48 ℃ when the crystallizing tank is full,

the second period is 20 hours, the sugar temperature is reduced from 35 ℃ to 22 ℃, and the temperature is reduced to be less than or equal to 0.65 ℃ per hour; the temperature difference between the cooling water temperature and the sugar temperature of the interlayer of the crystallization tank is less than or equal to 15 ℃; the stirring speed of the crystallizing tank is 3min/360 degrees; the crystals were collected by centrifugation.

5. The refining process according to claim 4, wherein the step 4) nanofiltration comprises the steps of: adding purified water into the crystal obtained in the step 3), and heating to 40 ℃ to obtain a glucose saturated solution; then the filtrate enters a nanofiltration membrane for filtration, and the filtrate is collected.

6. The refining process of claim 5, wherein the step 5) of cooling, filtering and drying comprises the steps of: cooling the filtrate to 7 deg.C, maintaining the temperature for 2 hr, filtering, collecting filtrate and precipitate, recrystallizing the filtrate in a crystallizer, and vacuum drying the precipitate at 45 deg.C to obtain glucose crystal.

7. The refining process of claim 5, wherein the nanofiltration membrane has a molecular weight cut-off of 300 Da.