KR102016701B1 - Method of preparing crystalline functional sweetener - Google Patents

Abstract

The present invention relates to a method for producing a crystalline functional sweetener, and more particularly, to a method for preparing a crystalline sweetener for increasing the crystal yield and increasing the particle size by controlling the content of impurities or the generation of impurities contained in a solution for preparing a crystal. It is about.

Description

Method of preparing crystalline functional sweeteners

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preparing a crystalline functional sweetener, wherein an allul for increasing the crystal yield and increasing the particle size by controlling the content of impurities converted from allulose in the process of preparing a crystalline functional sweetener, for example, allulose crystals It relates to a method for producing a Ross crystal.

Sugars and starch sugars represent the largest market in the world with about 65 trillion won, but as the consumer needs are strengthened worldwide as health-oriented functional and premium products, sugar alcohols such as xylitol and fructo oligosaccharides There is a growing market for functional sweeteners such as oligosaccharides, and functional sugars such as fructose and sweeteners such as sucralose and aspartame.

A sweetener that collectively refers to seasonings and food additives. Among many sweeteners, sugar, glucose, fructose, etc. are the most widely distributed as a natural ingredient in foods, and is most widely used in the manufacture of processed foods. However, as the negative side that 'sugar' causes tooth decay, obesity, diabetes, etc. has emerged, functional replacement sweeteners that can be used in place of sugar have attracted attention worldwide.

In recent years, allulose is one of the most popular sugars as a sugar which can replace sugar or fructose as a functional sweetener. Allulose can be prepared by chemical or biological methods, but because of the low content of allulose in the product, a process for purification and concentration is required. However, in the case of concentrated syrups, there is a limit to its application, but the demand for crystal powder is high, but allulose is difficult to crystallize due to low crystallinity. In addition, even in the case of producing allulose by a biological method using an allulose converting enzyme or a strain producing the enzyme, it is necessary to crystallize after increasing the purity of D-allulose due to the low conversion rate. When it is intended for the purpose of use, unresolved problems remain in the purification process, the purification yield, the crystallization yield, and the like.

Therefore, to reduce the content of impurities contained in the allulose solution for crystallization or the production of impurities in the allulose manufacturing process, to control the content of impurities converted from allulose to increase the crystal yield and increase the size of the particle size There is an urgent need for a method of preparing crystals.

The present invention relates to a method for producing allulose crystals for increasing the crystal yield and increasing the particle size by controlling the content of impurities or the production of impurities contained in the solution for preparing the crystals.

In addition, according to the present invention, allulose crystals having a uniform particle size can be prepared by appropriately controlling crystal grain growth, thereby reducing losses in the recovery process, thereby improving crystal yield and increasing productivity of the allulose crystallization process. It is intended to provide a process for the preparation of allulose crystals.

In addition, the present invention is an allulose crystal having a uniform particle size and reducing the loss in the recovery process to improve the crystal yield, the allulose crystal (Impurity-S) content adjusted to a specific concentration range It is to provide a composition for fire.

The present invention has a uniform particle size, can reduce the loss in the recovery process to improve the crystal yield, allulose conversion (Impurity-S) content for allulose crystallization composition adjusted to a specific concentration range And it relates to a method for producing allulose crystals using the same. The present invention also relates to a method for producing allulose crystals for increasing the crystal yield and increasing the particle size by controlling the content of impurities or the production of impurities contained in the solution for producing the crystals.

Allulose is unstable at lower pH and at higher temperatures (FIGS. 2 and 3), so that the content of allulose changes in the actual production process, especially in the concentration step. This problem lowers the high purity allulose purity and has a great influence on the crystallization step. In fact, in this process, the content of allulose conversion (Impurity) is additionally increased as the content of allulose is reduced, and it is confirmed in the present invention that this component greatly affects the crystallization of allulose. It was found that the presence of Impurity-S in the various allulose conversions acts as an inhibitor to the growth of allulose crystal grains, which greatly affects the grain size and crystal yield.

Thus, in the present invention, the allulose particle size is controlled by controlling the impurity (Smpurity-S) to a specific content or less, for example, 2% by weight or less in the pre-concentration step after the high purity separation process in performing the allulose crystallization process. It can be prevented from becoming small and allulose having a uniform particle size can be produced by appropriately controlling the crystal grain growth. In addition, by growing the particles to a uniform size, it is possible to reduce the loss in the recovery process, improve the crystal yield to increase the productivity.

Allulose syrup, which is a raw material used in the allulose crystallization process, may include various allulose conversions, which are impurities other than allulose generated during the production of allulose, or allulose conversion may be generated in the allulose crystallization process. . The shape, structure and size of the allulose crystal grains, the purity of the crystals, the rate of crystal formation, And crystal yield. The Impurity-S acts as an inhibitor to inhibit the growth of the crystal grains of allulose and thereby lower the crystal yield. The present invention provides a method that can increase the grain size of allulose and improve the yield by controlling the production process of allulose in the condition that no allulose conversion is produced.

The allulose conversion product (Impurity-S) may be a material having a ratio of mass / charge amount measured by LC / MS analysis in the range of 300 to 400 m / z, or eluting time analyzed by HPLC analysis 31 Material with a maximum peak measured at ± 2 minutes time. The LC / MS analysis was performed by HPLC analysis to analyze a material obtained by separating a material having a maximum peak measured at a dissolution time of 31 ± 2 minutes.

In addition, the allulose conversion (Impurity-S) may be an allulose-modified polymer, the allulose conversion (Impurity-S) is 1.5 times or more, for example 1.5 times to 10 times, preferably 2 It can be an allulose-modified polymer having a molecular weight of at least 2 times to 10 times or at least 2 times to 4 times. For example, the allulose-modified polymer, which is an allulose converting agent (Impurity-S), may be added to a dimer as the allulic acid conversion (Impurity-S) is continuously exposed to an external stimulus, for example, a high temperature or an acidic condition. It can also be converted to allulose modified polymers (tetramer analogs of allulose) with approximate molecular weights. This is due to a mechanism in which allulose is easily denatured by an external stimulus and the dehydration and condensation reactions are randomly repeated with the allulose or allulose converting material and converted to the modified polymer as described above.

Specifically, the component detected at the molecular weight of 341 m / z as a result of LC-MS analysis increases as the crystallization stock solution containing allulose is severely treated, and a dimer in which allulose is denatured by dehydration or condensation reaction (Dimer). ) It can be confirmed through molecular weight analysis that the substance has a similar structure. It can be predicted that this is an allulose-modified polymer as a material having a chemical formula of C12H22O11 as a result of inferring a structure through LC-MS analysis. In addition, as the heat treatment proceeded, it was confirmed that the content of the allulose-modified polymer (tetramer analog of allulose) having a molecular weight similar to the dimer of the allulic-modified polymer of C25H28O11, C24H42O21 or C24H44O22 also increased. It can be seen that allulose is easily denatured by an external stress, for example, heat treatment, and the dehydration and condensation reactions are randomly repeated with the allulose or allulose converting material to be converted into the above materials.

According to the present invention, the conversion contained in the allulose syrup, which is a raw material used in the allulose crystallization process, is performed by performing the production, separation, and / or purification process of allulose under the condition that no allulose conversion is produced. A method of removing or reducing the content of S) can be carried out. Accordingly, according to the method according to the present invention it is possible to reduce the content of Impurity-S of the crystallization stock solution to lower the content of impurities impeding the growth of crystals to improve the crystal shape and crystal yield.

Specifically, the content control of the conversion (Impurity-S) can be performed by preventing or reducing the production of Impurity-S, or by removing or reducing the generated Impurity-S. In one embodiment of the present invention, a method of controlling the production process of allulose under the conditions of preventing or reducing the production of allulose conversion, to increase the grain size of allulose, to form crystals in a shape close to a square shape, allulose yield Can improve. More specifically, by controlling the content of the allulose conversion (Impurity-S) component in the crystallization stock solution to 2 wt% or less, it is possible to improve the growth and yield of allulose crystal grains.

The method of preventing or reducing the production of Impurity-S can be achieved by controlling the conditions under which allulose conversion is not produced, in particular the conditions of the production process of allulose such as the control of pH, temperature and electrical conductivity in the concentration process. Can be. In addition, the method for removing or reducing the produced Impurity-S may be a method of performing activated carbon treatment or a method of secondary crystallization by re-dissolving crystals obtained in primary crystallization, and the like. You can use the removal method.

Specifically, the method of generating impurities or adjusting the content may be performed by one or more of the following methods.

As an example, one example of a method for preventing or reducing the production of allulose conversions (Impurity-S) in an allulose production process is that the allulose production process is performed at pH 4 or above and / or temperature below 70 ° C. It may be a method. Specifically, since the pH is 4 to 7 or pH 4 to 6 conditions, the temperature is relatively stable at less than 70 ℃, preferably below 60 ℃, reaction in allulose production process such as decolorization, ion purification, high purity separation It is preferable that the temperature of the liquid is controlled not to exceed 70 ° C, preferably 60 ° C, and in particular, by dividing the concentration step into two or more steps, so that the liquid is not continuously exposed to external stimuli.

In order to prevent or reduce the production of Impurity-S in the allulose production process, the concentration process may be carried out in the allulose fraction obtained in the SMB chromatography separation process at a temperature condition of less than 40 to 70 ℃, optionally The concentration process can be carried out in at least two stages. For example, if the concentration process is carried out in two stages, the concentration of allulose syrup can be performed first to a concentration of 30 to 50 Bx, and the primary concentrate can be further concentrated to a concentration of 60 to 85 Bx. Preferably, the method may further include an activated carbon treatment process between the primary concentration process and the secondary concentration process to remove or reduce the content of Impurity-S contained in the concentrate.

In another embodiment, the method of removing or reducing the content of the conversion (Impurity-S) contained in the allulose syrup, which is a raw material for allulose crystallization, may process activated carbon to act as an impurity or induce degeneration of allulose. It adsorbs and removes a polymer or a low molecular organic substance, a color ionic substance, or a protein.

In detail, the allulose reaction solution obtained from the substrate may be subjected to SMB chromatography separation to remove or reduce the content of the conversion (Impurity-S) by performing a process of treating with the activated carbon before concentrating the allulose fraction obtained. have. In the activated carbon process, the allulose fraction obtained in the SMB chromatography separation process may be further subjected to an ion purification process.

In the activated carbon process, the activated carbon is brought into contact with an allulose solution to react at a temperature of 40 to 50 ° C. for 0.5 to 5 hours, and then a reaction solution including the activated carbon is subjected to a solid-liquid separation process to obtain a filtrate, and impurities are filtered residues. Can be removed. The filtration may be performed using a filtration equipment such as a filter press.

In the activated carbon reaction process may be optionally stirred, the stirring speed of the reaction solution may be 5 to 500rpm, preferably 50 to 300rpm. The stirring speed may be appropriately selected in consideration of the dispersion degree of activated carbon and the cost of stirring. The contact time of the activated carbon and the reaction solution may be appropriately selected in consideration of the dispersion degree of the activated carbon and the removal efficiency of impurities. For example, the contact time may be 0.5 to 5 hours, preferably 0.5 to 2 hours. Impurity removal, for example, may not be sufficiently decolorized, and long contact time may cause breakage and browning of main components.

The activated carbon used in the activated carbon treatment process may be derived from coal-based or wood-based, and may selectively remove impurities according to the pore particle size of the activated carbon.

As a further example, a method of preventing or reducing the production of the allulose conversion (Impurity-S) of the allulose crystallization composition is to perform recrystallization. The first crystallization was performed with an allulose solution subjected to a high purity separation and concentration process, the supernatant was removed from the primary crystallization stock solution, and the allulose crystals recovered by dehydration were dissolved again in water to prepare an allulose solution for crystallization. By introducing into the primary crystallization process, the content of allulose conversion (Impurity-S) in the primary crystallization process can be removed or reduced.

Accordingly, one embodiment of the present invention provides a method of controlling the content of the allulose conversion (Impurity-S) contained in the allulose composition for crystallization to 2% by weight or less based on the solids content of the composition.

The method may be carried out by adjusting one or more conditions selected from the group consisting of pH conditions and temperature conditions of the composition, wherein the pH conditions may range from pH 4 to 7 or temperature conditions below 70 ° C.

The allulose composition for crystallization may be prepared by treating the allulose-containing reaction solution by SMB chromatography separation process, and concentrating the obtained allulose solution at a temperature condition of less than 40 to 70 ° C. The concentration process may be performed by dividing the process into at least two stages. The concentration of the allulose solution may be primarily performed to have a concentration of 30 to 50 Bx, and the first concentrate may be secondly concentrated to a concentration of 60 to 85 Bx. The activated carbon treatment process may be further performed before the concentration process.

Another embodiment of the present invention, the content of the allulose conversion (Impurity-S) based on 100% by weight total solids content of the composition is 2% by weight or less, preferably 1.5% by weight or less, 1.3% by weight or less, 1.1 The present invention relates to a composition for allulose crystallization containing not more than% by weight, preferably not more than 1.0% by weight, more preferably no impurities.

Preferably, the allulose crystallization composition has an allulose content of 90% by weight, 91% by weight, 92% by weight, 93% by weight, 94% by weight based on 100% by weight of the total solid content of the composition. Or more, or 95% by weight or more.

The viscosity of the allulose composition for crystallization may be 2 cps to 200 cps at a temperature of 45 ° C of the composition, the electrical conductivity is less than 1,000uS / cm, for example 0.01 to 1,000uS / cm, preferably 30 uS / cm For example, it may be 0.1 to 30 uS / cm. The lower the electrical conductivity of the composition for allulose crystallization, the more preferable for crystallization. The electrical conductivity of the allulose syrup is a value measured based on a solid content of 30 Bx.

The allulose solution for crystallization may have a solid content of at least 60 to 85 brix, for example more than 60 brix to 80 brix, 65 to 85 brix, 65 to 80 brix, or 68 to 85 brix.

One embodiment of the present invention relates to a method for producing allulose crystals using an allulose solution for crystallization, more specifically, the content of the allulose conversion (Impurity-S) based on 100% by weight of the total solids content of the composition. Providing a composition for crystallization of allulose comprising 2 wt% or less, preferably 1.5 wt% or less, 1.3 wt% or less, 1.1 wt% or less, preferably 1.0 wt% or less, and cooling the aqueous solution of allulose To produce allulose crystals.

In one embodiment of the present invention, the method for producing allulose crystals comprises the steps of secondary ion purification of the allulose fraction obtained in the SMB chromatography separation process, concentrating the ion purified allulose fraction, the concentrate Crystallizing allulose from to obtain allulose crystals and allulose crystallization mother liquor, and optionally further comprising a recovery process, a washing process and a drying process of allulose crystals.

In addition, the allulose fraction obtained in the SMB chromatography separation process or a solution obtained by ionizing the allulose fraction may be treated with activated carbon before the concentration step to reduce or remove the content of the allulose conversion (Impurity-S). Can be. In addition, the crystallization of the allulose solution for crystallization may be carried out first crystallization and the obtained crystals are dissolved second crystallization to reduce or remove the content of the allulose conversion (Impurity-S).

In one embodiment of the present invention, the method for preparing the crystallization allulose composition, the step of secondary ion purification of the allulose fraction obtained by treating the reaction solution containing allulose prepared from the substrate by SMB chromatography separation process And the step of concentrating the ion-purified allulose fraction, or including both an ion purification process, an activated carbon treatment process, or an activated carbon treatment process and an ion purification process for treating the allulose fraction obtained by treatment with an SMB chromatography separation process. can do.

Providing the crystallization allulose composition, the content of the allulose conversion (Impurity-S) 2% by weight or less, preferably 1.5% by weight or less, based on 100% by weight of the total solid content contained in the crystallization composition , Not more than 1.3 wt%, not more than 1.1 wt%, preferably not more than 1.0 wt% or preferably no allulose conversion (Impurity-S).

In the method for preparing allulose crystals according to the present invention, the yield of allulose crystals may be 45% or more, preferably 48% or more, 50% or more, more preferably 55% or 60% or more.

The content control of the allulose conversion, may be carried out by adjusting at least one selected from the group consisting of pH conditions and the temperature of the allulose solution, the pH control, pH 4 to 7 range, pH 4.5 to 7, or pH 5 to 7, preferably at pH 5 to 7, the temperature of the solution is less than 70 ℃, preferably less than 30 to 70 ℃, 30 to 69 ℃, 30 to 65 ℃ or 30 to 60 ℃ It can be achieved by adjusting the range.

Allulose is unstable at lower pH and higher temperature, so that the content of allulose changes in the actual production process, especially in the concentration step. This problem lowers the allulose purity of the allulose solution, which greatly affects the crystallization step. As the content of allulose is reduced in the process, the content of a specific allulose conversion (Impurity) additionally produced is increased, and this component has been found to have a great influence on the crystallization of allulose. If the content of more than 2% of Impurity-S is present in various allulose conversions, it can be seen that it acts as a major obstacle to the growth of allulose crystal grains. It was confirmed that it affects.

Specifically, as shown in Figures 2 and 3, the higher the storage temperature, the allulose content was decreased, the content of the allulose conversion (Impurity-S) was increased. As shown in Figures 4 and 5, the lower the pH at 70 ℃ temperature allulose content is reduced, the production amount of the allulose conversion is increased.

The allulose composition for crystallization according to the present invention may be a reactant containing allulose obtained by a biological or chemical method, an allulose fraction obtained by SSMB chromatography separation of the reactant, or a concentrate of the allulose fraction. Prior to performing the concentration process for preparing the allulose concentrate, the ionic refining and / or activated carbon treatment process may be further performed, the concentration process may be carried out in at least two steps. The allulose-containing reactant is obtained from a fructose substrate by a biological or chemical method, preferably by a biological method using an allulose converting enzyme or a microorganism producing the enzyme.

The allulose reaction solution may perform a separation process of the psychic conversion reactant including an ion purification and a separation process of the mosquito layer (SMB) chromatograph. In one specific embodiment, the sicose conversion reactant is separated into ionic purification and SMB chromatography separation process to a psycose fraction and a fructose raffinate having a higher cyclic content than the conversion reactant, and the psycose fraction is subjected to a psychos concentration process. It is fed into the crystallization process.

The content of allulose in the allulose solution to obtain allulose crystals should be included in a high concentration in a supersaturated state, but since the content of allulose in the allulose conversion reactants is low, direct crystallization cannot be performed and allulose before the crystallization step Purification and concentration to the desired level should be carried out to increase the content.

The method of obtaining the composition may be performed at a temperature of the high purity allulose solution is less than 70 ℃, for example 40 or more to less than 70 ℃, specifically using a thin film concentrator or multi-effect evaporator. have. In one embodiment of the present invention, the step of concentrating the purified allulose solution may be performed at a temperature condition of less than 40 to 70 ℃. If the temperature of the concentrate is 70 ℃ or more may be a thermal denaturation of D- allulose, thereby producing or increasing the allulose conversion (Impurity-S) according to the present invention. In addition, since the temperature of the reactant is rapidly increased by the heat of evaporation as the concentration proceeds, it must be rapidly concentrated while maintaining the temperature of the concentrate below 70 ° C.

Specifically, the concentration of the allulose fraction obtained in the SMB chromatography separation process can be carried out in a variety of ways, the solids content of the concentrate can be 70 or more Brix. For example, the allulose fraction obtained by the simulated moving bed adsorptive separation method (for example, solid content of 20 to 30% by weight) may be concentrated to a solid content of 60 brix or more through a concentration process. The composition for allulose crystallization according to the present invention has a solid content of 60 to 85 brix (Bx) or less, for example, greater than 60 brix to 85 brix, 65 to 85 brix, 70 to 85 brix, 75 to 85 brix, 60 Greater than 8 to 83.5 brix, 65 to 83.5 brix, 70 to 83.5 brix, or 75 to 83.5 brix.

For example, the composition for crystallization may be an allulose fraction obtained by performing a simulated moving bed (SMB) chromatography separation process using a column chromatograph filled with a cation exchange resin with calcium active groups. Specifically, to obtain an allulose conversion reactant for converting fructose-containing raw material to allulose using a biological catalyst, and the activated carbon treatment, ion purification and simulated moving bed (SMB) chromatography separation of the allulose conversion reactant It may be an allulose fraction obtained by performing the process. The allulose fraction may be obtained by itself or by an ion purification process obtained in the SMB chromatographic separation process. The fructose content of the fructose-containing raw material is 85% by weight or more based on 100% by weight of the total solid content of the fructose-containing raw material, and the allulose conversion of the allulose conversion reaction is to use a biological catalyst having 15% to 70%. Can be.

The allulose fraction obtained in the SMB chromatographic separation process may further be subjected to an ion purification and / or activated carbon treatment process before performing the concentration process.

The method for producing allulose crystals according to the present invention can be crystallized by adjusting the temperature and concentration of the allulose concentrate solution, specifically the supersaturation state required for crystallization is lowered the temperature of the allulose solution or D- It can be maintained by varying the concentration of D-allulose in the allulose solution. In one embodiment of the present invention, the crystallization progress is monitored by taking samples at regular intervals in the crystallization step and visually or by microscope, or by analyzing the sugar concentration in the supernatant obtained from centrifugation of the sample, and Depending on the result, the temperature or the concentration of D-allulose can be adjusted. In order to prepare allulose crystals, when the allulose concentrated solution is cooled and crystallized, it may be rapidly cooled to a temperature range of 10 to 25 ° C. through a heat exchanger, and then repeatedly heated and cooled to induce crystal growth. .

The method for producing allulose crystals according to the present invention can be crystallized by adjusting the temperature and concentration of the allulose concentrate solution, specifically the supersaturation state required for crystallization is lowered the temperature of the allulose solution or D- It can be maintained by varying the concentration of D-allulose in the allulose solution. The method for preparing allolose crystals according to the present invention can be carried out by various methods, preferably by a cooling method. One example of the cooling method according to the present invention is to cool the allulose solution to a temperature of 35 to 10 ° C to induce a supersaturated state to produce crystals. Cooling rate is preferably maintained at 0.01 to 20 ℃ / min, low cooling rate is a long crystallization time, the productivity can be low, high cooling rate is difficult to recover the small crystal size crystals are formed Can be.

The method for preparing allulose crystals includes the steps of generating crystal nuclei in an allulose solution containing 90% by weight or more of allulose and having an electrical conductivity of 1,000 to 50 µS / cm or less, and cooling the temperature of the solution to form crystals. Growth may be included.

Specifically, the method for preparing allulose crystals includes 90% by weight or more of allulose, and slowly stirring 60 to 85 brix allulose solution at 20 to 40 ° C, or 30 to 40 ° C, for example, 35 ° C. Generating crystal nuclei, and cooling the temperature of the solution to 10 ° C. to grow crystals. The method may further comprise the step of increasing the temperature of the solution in the range of 30 ~ 35 ℃ re-dissolve the microcrystals generated during cooling at least one time. The manufacturing method of the allulose crystal may further include the step of adding the seed (seed). The seed addition step and the redissolution step may be optionally included in the method for preparing allulose crystals, respectively, or may include both of the above steps.

In general, it is known that the larger the size of the allulose crystals, the better the physical properties and the ease of use.In order to prepare such a large size crystal, both the seed crystal and the main crystallization process, which are classified as a transfer process, should be performed. The crystallization process according to the invention can easily produce crystals of relatively large size in a high yield even in one step process.

In addition, the crystallization process may be performed to dissolve the fine crystals by raising the temperature of the solution to 30 to 35 ℃ in order to re-dissolve the fine crystals generated during the cooling in the crystal growth process. In the crystallization process according to the present invention, the crystal growth process and the microcrystal melting process may be performed at least once or more times.

In the process of preparing the crystal, a seed may be further added for the purpose of increasing the crystal formation rate and size.

In a specific embodiment according to the present invention, the allulose crystals comprise 90% by weight or more of allulose on a solids basis, and a small amount of crystal nucleus is formed by slowly stirring the allulose solution having a total solids content of 60 to 85 brix at 35 temperature. After cooling, the temperature is decreased by 1 per hour, cooled to a temperature of 10 ° C. to grow crystals, and optionally, the temperature of the solution is raised to 30 to 35 ° C. to re-dissolve the fine crystals formed during cooling. The step of dissolving can be repeated at least once or more to produce allulose crystals.

The method for producing allulose crystals according to the present invention further comprises recovering the allulose crystals obtained in the crystallization step by various solid-liquid separation methods such as centrifugation, washing with deionized water, and drying. It may include. The drying step may be performed in a fluidized bed dryer or a vacuum dryer, but is not limited thereto.

Allulose crystals can be prepared by the method of cooling the allulose composition for crystallization according to the present invention. The allulose composition for crystallization is as described above.

The allulose contained in the allulose crystal may be at least 94% by weight, at least 95% by weight, at least 96% by weight, at least 97% by weight, at least 98% by weight or at least 99% by weight, based on 100% by weight of total solids content. .

In the present invention, "purity of crystals" means the purity of crystals of allulose. Physical properties including the purity of the crystals of the present invention can be obtained by methods such as X-ray powder diffraction analysis, differential scanning calorimetry (DSC) analysis, infrared spectroscopy (FTIR) analysis, HPLC analysis, LC / MS analysis, and the like. Purity can be specifically analyzed by HPLC chromatography.

The allulose crystal according to an embodiment of the present invention may be an allulose crystal having an X-ray spectral spectrum having a peak at diffraction angles (2θ) ± 0.2 ° of 15.24, 18.78, and 30.84 in the X-ray spectral spectrum. In one embodiment of the present invention, the X-ray spectral spectrum has diffraction angles (15) of 15.24, 18.78, 30.84 and 31.87 at diffraction angles (2θ) ± 0.2 ° of 15.24, 18.78, 30.84 and 28.37 in the X-ray spectral spectrum. Or an allulose crystal having an X-ray spectral spectrum with peaks at diffraction angles 2θ of ± 0.2 °, or at 15.24, 18.78, 30.84, and 47.06. The diffraction angle having a peak in the X-ray spectral spectrum of the allulose crystal is the X-ray diffraction analysis results are displayed by selecting the upper (Relative Intensity%) main peak and the form-specific peak.

The allulose crystals according to the present invention may be obtained by various crystallization methods, but may be characteristics measured by allulose crystals prepared by a cooling method.

The allulose crystal according to an embodiment of the present invention may have a Tm temperature of 125.8 ° C. ± 5 ° C. or a melt enthalpy (ΔH) of 200 to 220 J / g according to DSC analysis, wherein the Tm is 125.8 ° C. ± 3 ° C. Can be. Differential scanning calorimetry (DSC) is manipulated according to a temperature gradient and measures the energy provided to maintain the temperature increase of the allulose powder sample. In the DSC analysis of the crystals, it can be predicted that the higher the heat capacity, the easier it is to melt, and the higher the heat capacity and the narrower the endothermic peak, the more uniform and hard the crystal is formed.

Another embodiment of the present invention, the allulose crystals prepared by the allulose crystallization composition, preferably may be allulose crystals having one or more characteristics selected from the group consisting of (1) to (5). :

(1) having a powder X-ray spectral spectrum having a peak at diffraction angles (2θ) ± 0.2 ° of 15.24, 18.78, and 30.84 on a powder X-ray spectral spectrum,

(2) have a Tm temperature of 125.8 ° C ± 5 ° C according to differential scanning calorimetry (DSC),

(3) having a melt enthalpy (ΔH) of 200 to 220 J / g according to differential scanning calorimetry;

(4) having an average long diameter of 350 µm or more, preferably 350 to 2,000 µm, and

(5) The ratio (= long diameter / short diameter) of the long diameter length (micrometer) to the short diameter of the allulose crystal is in the range of 1.0 to 8.0.

 In the allulose crystal according to the present invention, the average short diameter of the crystal may be 50 to 1,000 μm, preferably 50 to 500 μm, and the average long diameter of 350 μm or more, preferably 350 to 2,000 μm. Μm, more preferably 400 micrometers or more and 2,000 μm.

Further, the length (micrometer) ratio (= long diameter / short diameter) of the long diameter to the short diameter of the allulose crystal according to the present invention is 1.0 to 8.0, 1.0 to 6.9, 1.0 to 6.0, 1.0 to 5.5, 1.0 To 5.0, 1.1 to 8.0, 1.1 to 6.9, 1.1 to 6.0, 1.1 to 5.5, 1.1 to 5.0, 1.3 to 8.0, 1.3 to 6.9, 1.3 to 6.0, 1.3 to 5.5, 1.3 to 5.0, 1.5 to 8.0, 1.1 to 6.9 , 1.5 to 6.0, 1.5 to 5.5, 1.5 to 5.0, 2.0 to 8.0, 2.0 to 6.9, 2.0 to 6.0, 2.0 to 5.5, 2.0 to 5.0.

According to the powder XRD pattern analysis of the allulose crystals according to the present invention, the allulose crystals according to the present invention are pure crystal particles and have a rectangular hexahedron or a structure close thereto. The closer the crystal structure of the present invention is to a cubic system, the more preferable the crystal uniformity and firmness are.

In addition, the more uniform the crystal produced in the crystallization process of allulose, the higher the strength of the crystal and the minimization of particle breakage, thereby making the particle size distribution uniform, thereby improving flowability. On the other hand, when the uniformity is low, it is micronized by the cracking of the crystal grains in the drying and conveying step, and may be relatively easy to melt, adversely affecting the quality of the product.

Compared with the finely divided powder, the allulose crystal of the present invention has good flowability, is not caking well, and is stable at storage, and has easy characteristics of distribution and handling. In addition, since the allulose powder has a lower calorie than sugar, and the sweetener has properties similar to sugar, it is easy to prepare mixed sweeteners, solid mixed sweeteners, chocolate, chewing gum, instant juices, instant soups, granules, tablets, and the like. It can be carried out advantageously. In addition, the allulose crystal powder may be used in a variety of compositions, such as food and beverages, food, feed, feed, cosmetics, pharmaceuticals.

In the method for preparing allulose crystals according to the present invention, by controlling the content of the allulose conversion (Impurity-S) contained in the solution for preparing the crystals, it is possible to prevent the size of the allulose particles from becoming smaller, By appropriately controlling growth, it is possible to produce allulose with uniform particle size. In addition, by growing the particles to a uniform size, it is possible to reduce the loss in the recovery process and to improve the productivity by increasing the crystal yield.

1 is a graph showing the change of allulose content when the allulose syrup having a pH of 70 Brix at different temperatures was stored.
Figure 2 is a graph showing the change in content of the allulose conversion when the allulose syrup of 70 Brix concentration of pH 5 stored at different temperatures.
FIG. 3 is a graph showing the change in content of allulose when allulose syrup having a different pH and 70 Brix concentration is stored at a temperature of 70 ° C.
Figure 4 is a graph showing the change in content of allulose conversion when allulose syrup having a different pH and 70 Brix concentration of the allulose syrup is stored at a temperature of 70 ℃.
5 is an optical micrograph measured at a magnification X100 of the allulose powder obtained in Example 5. FIG.
6 is a scanning electron microscope (SEM) photograph measured at magnification X50 of the allulose powder obtained in Example 5. FIG.
7 is an infrared spectroscopic analysis (IR) spectrum of the allulose crystal obtained in Example 5. FIG.

The invention is illustrated in more detail by the following examples. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited thereto.

Example  One: Allulose  Crystal manufacturing

Allulose syrup was prepared from fructose substrates by a biological method substantially the same as that described in Korean Patent Laid-Open Publication No. 2014-0054997. To remove impurities such as colored and ionic components, allulose syrup is twice as long as the ion exchange resin per hour in a room temperature column filled with a cation exchange resin, an anion exchange resin and a resin mixed with a cation and an anion exchange resin (1 ~ 2 2x), the solution was passed through a volumetric speed, desalted, and separated into a high-purity allulose solution using chromatography packed with calcium (Ca2 +) type ion exchange resin.

By the high purity separation process (SMB), allulose high purity syrup containing 97% by weight of allulose was obtained at a concentration of 35 Bx (w / w%), and concentrated to 81 Bx (w / w) containing 97% by weight of allulose. %), Crystallized allulose syrup having an electrical conductivity of 12 uS / cm. The electrical conductivity of the allulose syrup is a value measured based on a solid content of 30 Bx.

The concentrated allulose syrup was slowly cooled to a temperature of 10 ° C. at a temperature of 35 ° C. in which a supersaturated state was grown, thereby growing crystals. At this time, allulose seed was added and stirred slowly at a temperature of 35 ° C. to produce a small amount of crystal nuclei, and then the temperature was decreased by 1 ° C. per hour to grow the crystals. In order to re-dissolve the solution temperature was increased to 30 ~ 35 ℃ to perform a process for dissolving the fine crystals. Crystallization was performed by repeating the crystal growth process and the microcrystal dissolution process at least once. The allulose crystals prepared herein were recovered by removing the mother liquor by centrifugal dehydration, washing the crystals with cooling water, and then drying them.

The allulose content of the crystallization stock solution, the content of the allulose conversion product (Impurity-S), and the purity of the allulose crystal were performed by HPLC analysis, and the analysis conditions were as follows.

Analytical column: Biolad Aminex HPX-87C column

Mobile phase: water

Flow rate: 0.6ml / min

Column temperature: 80 ℃

Detector: RI detector

As a result of the HLPC analysis, the content of allulose conversion (Impurity S) of the aqueous solution of crystallization of allulose was 0.4% by weight, and the content of allulose was 97.0% by weight, based on 100% by weight of the solid content of the aqueous solution of allulose for crystallization. .

The allulose crystal yield prepared by the above method was 63.6%. The crystal yield is expressed as a percentage of the weight of the recovered allulose crystal powder after dehydration washing relative to the solid content of the raw material allulose syrup for crystallization.

Example  2 and 3: Allulose  Crystal manufacturing

35 Bx (w / w%) of an allulose high purity syrup comprising 96.6% by weight of allulose in Example 2 by a high purity separation process (SMB) by substantially the same method as the preparation of allulose of Example 1; Obtained in concentration, an allulose high purity syrup containing 95.8% by weight of allulose in Example 3 was obtained at a concentration of 35 Bx (w / w%). Concentrating the allulose solution, Example 2 is 81 Bx (w / w%) concentration containing 96.6% by weight of allulose, 81 Bx (w / w%) concentration for crystallization having an electrical conductivity of 14 uS / cm To prepare an allulose syrup, Example 2 is a 81 Bx (w / w%) concentration containing 95.8% by weight of allulose, 81 Bx (w / w%) concentration for crystallization having an electrical conductivity of 14 uS / cm Allulose syrup was prepared.

In the same crystallization method as in Example 1, crystallization was performed using the concentrated allulose syrup, the crystals were washed with cooling water, and then dried and recovered.

In the same manner as in Example 1, the content of allulose and allulose conversion (Impurity-S) and the purity of the allulose crystallization of the crystallization stock solution was performed the following HPLC analysis, the results are shown in Table 1 Indicated.

Example  4: Allulose  Crystal manufacturing

The allulose high purity syrup containing 97.0% by weight of allulose was obtained by a high purity separation process (SMB) by the same method as the preparation of allulose of Example 1, at a concentration of 35 Bx (w / w%).

In order to minimize the impurities contained in the allulose syrup, activated charcoal suitable for removing impurities was treated at 40 ° C. for 30 minutes and then filtered. Allulose syrup after activated charcoal treatment was concentrated to a concentration of 81 Bx (w / w%) to crystallize allulose having an electrical conductivity of 81 uF / w%, containing 10.7 wt% allulose, and an electrical conductivity of 10 uS / cm. Syrup was prepared.

The concentrated allulose syrup was slowly cooled to a temperature of 10 ° C. at a temperature of 35 ° C., which became a supersaturated state, and crystals were grown. At this time, allulose seed was added and stirred slowly at a temperature of 35 ° C. to produce a small amount of crystal nuclei, and then the temperature was decreased by 1 ° per hour to grow the crystals. In order to re-dissolve the solution temperature was increased to 30 ~ 35 ℃ to perform a process for dissolving the fine crystals. Crystallization was performed by repeating the crystal growth process and the microcrystal dissolution process at least once. The allulose crystals prepared herein were recovered by removing the mother liquor by centrifugal dehydration, washing the crystals with cooling water, and then drying them.

Example  5: Allulose  Crystal manufacturing

The allulose high purity syrup containing 97.0% by weight of allulose was obtained by a high purity separation process (SMB) by the same method as the preparation of allulose of Example 1, at a concentration of 35 Bx (w / w%).

Concentrating the allulose syrup to a concentration of high purity allulose syrup containing 97% by weight of allulose based on 100% by weight of solid content to a concentration of 81Bx (w / w%) to have an electrical conductivity of 8 uS / cm Crystallized allulose syrup was prepared. In the same crystallization method as in Example 1, crystallization was performed using the concentrated allulose syrup, the crystals were washed with cooling water, and then dried and recovered.

The obtained primary crystals were dissolved in water to prepare an allulose solution 81.2Bx, and the allulose solution was analyzed by HPLC analysis of Example 1, and the content of the allulose conversion product (Impurity S) was 0.07 weight. %, Allulose content was 99.5% by weight.

As a raw material of the secondary crystallization process, the secondary crystallization process was performed in the same manner as the primary crystallization method with the prepared allulose solution. The prepared allulose crystals were removed from the mother liquor by centrifugal dehydration, the final crystals obtained by secondary crystallization were washed with cooling water, and then dried and recovered to prepare secondary crystals. The yield of secondary crystals was 62.5%.

division Crystallization of undiluted
Allulose Content (%) Crystallization of undiluted
Impurity-S content (%) % Yield Example 1 97.0 0.4 63.6 Example 2 96.6 0.3 61.9 Example 3 95.8 0.5 61.6 Example 4 97.3 0.2 62.0 Example 5 99.5 0.07 62.5

As shown in Table 1, compared to the allulose crystal yield of Examples 1 to 3 exceeds 60%, Comparative Example 1 is an allulose conversion (Impurity-S) even though the allulose content of the crystallization stock solution is high When the content of more than 2% by weight can not obtain a proper crystals, it was confirmed that the crystal yield is greatly reduced due to the small crystals.

Comparative example  One: Allulose  Crystal manufacturing method

The crystallization stock solution was prepared by treating the allulose crystal obtained by performing primary crystallization in Example 5 in water for 3 hours at a pH of 3.5 and a temperature of 80 ° C. using a crystallization stock solution for secondary crystallization. . In the same crystallization method as in Example 1, crystallization was performed using the concentrated allulose syrup, the crystals were washed with cooling water, and then dried and recovered.

In the same manner as in Example 1, the content of the allulose and allulose conversion (Impurity-S) of the crystallization stock solution, and the purity of the allulose crystals were performed by the following HPLC analysis, the results are shown in Table 2 Indicated.

Comparative example  2 to 4: Allulose  Crystal manufacturing method

Using the crystallization stock solution for secondary crystallization prepared by dissolving allulose crystals obtained by performing primary crystallization in Example 5 in water, heat treatment was performed at pH 5.6, 75 ° C. for 6, 13, or 24 hours. To prepare a crystallization stock solution, the content of allulose and allulose conversion contained in the crystallization stock solution is shown in Table 2 below.

The crystallization proceeded using the prepared crystallization stock solution was carried out in substantially the same manner as in Example 1. Specifically, Comparative Examples 2 to 4 were obtained with different heat treatment times in Table 4 below to prepare a crystallization stock solution having the content of allulose and allulose conversion of Table 2, followed by an allulose crystallization process.

In the same manner as in Example 1, the content of the allulose and allulose conversion (Impurity-S) of the crystallization stock solution, and the purity of the allulose crystals were performed by the following HPLC analysis, the results are shown in Table 2 Indicated.

division Crystallization of undiluted
Allulose Content (%) Allulose conversion
content(%) % Yield Comparative Example 1 97.0 2.1 42.4 Comparative Example 2 98.5 0.65 55.8 Comparative Example 3 96.2 1.50 48.4 Comparative Example 4 93.3 2.40 29.1

In Comparative Example 4, in the crystallization stock solution, allulose had a low purity and a high content of allulose converting material. Thus, it was difficult to grow crystal grains and formed as fine crystals, which made it very difficult to dehydrate and wash the crystals. As in Comparative Examples 1 and 4, it was confirmed that the higher the content of the allulose conversion product, the smaller the crystal grain size growth was, and the finer crystals were formed.

Experimental Example  One: Allulose Of the conversion (Impurity S)  LC-MS Analysis

(One) Example  2 of Allulose Convertible (Impurity S) analysis

In the HPLC analysis of the allulose syrup for crystallization used in Example 2, an impurity fraction separated at a peak of 31 ± 2 minutes was directly obtained, and the diluted solution was freeze-dried and concentrated to a concentration of about 100-fold. Used for analysis. The liquid chromatography / mass spectrometer (LC / MS system, model name: LTQ, manufacturer: Thermo Finnigan, USA) was used to analyze the molecular weight of the impurity, and measured by LC / MS analysis of the allulose conversion (Impurity S). The molecular weight was a substance having a range of 300 to 400 m / z (ratio with mass / charge amount) (FIG. 6)

(2) Comparative example  2 to 4 Allulose Convertible (Impurity S) analysis

In the HPLC analysis, according to the substantially same method as the LC-MS analysis method, the heat-treated crystallization stock solution used in Comparative Examples 2 to 4 was used for LC-MS analysis. The LC-MS analysis of the molecular weight change of the allulose and allulose conversion product according to the heat treatment was performed, and the analysis results of the allulose content and the allulose conversion content (%) contained in the crystallization stock solutions used in Comparative Examples 2 to 4 were obtained. Table 3 and Figure 7 below.

Table 3 shows data obtained by LC-MS analysis of allulose syrup for each heat treatment time (Comparative Examples 2 to 4), and the numerical value obtained by converting the area value of the peak detected for each molecular weight (m / z) as a percentage. It is shown in the table. In Row 1 of Table 3, the molecular weight 179.1 m / z is allulose. Rows 4, 8, and 10 in Table 3 indicate that the content of the allulose conversion (Impurity S) is increased after the heat treatment, and the content of the allulose conversion (Impurity S) is decreased after the heat treatment in the remaining rows.

Row m / z Example 5 Comparative Example 2 Comparative Example 3 Comparative Example 4 Formula Finder Result One 179.1 56.68 38.53 31.65 24.75 C6H12O6 2 225.1 9.27 6.26 5.12 4.26 C7H14O8 3 251.1 0.36 1.05 1.09 1.18 C9H16O8 4 341.1 6.03 16.68 18.99 19.71 C12H22O11 5 359.1 21.31 14.66 11.50 8.42 C12H24O12 6 387.1 1.37 3.44 3.91 4.76 C13H24O13 7 485.1 0.04 0.06 0.17 0.61 C18H30O15 8 503.2 0.44 2.11 5.53 9.89 C25H28O11 9 665.2 0.06 0.16 0.60 2.03 C24H42O21 10 683.2 4.13 16.01 18.50 18.51 C24H44O22 11 711.2 0.02 0.02 0.15 0.56 C25H44O23 12 827.3 0.01 0.02 0.06 0.35 C37H48O21 13 845.3 0.09 0.60 1.37 1.92 C30H54O27 14 1007.3 0.01 0.13 0.90 2.31 C36H64O32

As shown in the analysis results, it was confirmed that as the heat treatment time increases, the allulose content is lowered, and the content of impurities is higher in molecular weight analysis. In Row 1 of Table 3, the molecular weight of 179.1 m / z is allulose, and it was confirmed that the numerical value of the peak area value decreased after the heat treatment. On the other hand, the component detected at the molecular weight of 341 m / z (Table Row5) increases as the crystallization stock solution containing allulose is heat treated, and a dimer-like substance in which allulose is modified by dehydration or condensation reaction. It was confirmed through the molecular weight analysis. It can be predicted that this is an allulose-modified polymer as a material having a chemical formula of C12H22O11 as a result of inferring a structure through LC-MS analysis. In addition, as the heat treatment proceeded, it was confirmed that the content of the allulose-modified polymer (tetramer analog of allulose) having a molecular weight similar to the dimer of the allulic-modified polymer of C25H28O11, C24H42O21 or C24H44O22 also increased. This is because the allulose is easily denatured by an external stress, for example, an acidic pH and / or heat treatment in Comparative Example 2-4, so that the dehydration and condensation reactions are randomly repeated with the allulose or allulose conversion. It can be thought of as being converted into materials.

Experimental Example  2: Allulose  Stability analysis

In order to test the effect of the temperature of the allulose and the allulose conversion, allulose syrup containing 97% by weight of allulose of Example 1 was divided into 30 g of the same amount and stored in each temperature bath having different temperatures, and sampled over time. The content change was analyzed, and the results are shown in FIGS. 1 and 2.

1 is a graph showing the change of allulose content when the allulose syrup having a pH of 70% Brix concentration was stored at different temperatures. Figure 2 is a graph showing the change in content of the allulose conversion when the allulose syrup having a concentration of 70% Brix, pH 5, stored at different temperatures. As shown in Figure 1 and 2, the higher the storage temperature, the allulose content was decreased, the content of the allulose conversion (Impurity-S) was increased.

In addition, in order to test the effect of the pH of the allulose and allulose conversion, the allulose content of 97.0% syrup of Example 1 was adjusted to different pHs using caustic soda and hydrochloric acid solution, and then the same temperature (70 ° C) ), And the change in content was analyzed by sampling over time, and the results are shown in FIGS. 3 and 4.

Figure 3 is a graph showing the change of allulose content when the allulose syrup of 70 Brix concentration of different pH is stored at 70 ℃ temperature. Figure 4 is a graph showing the change in content of the allulose conversion when the allulose syrup of 70Brix concentration of different pH is stored at 70 ℃ temperature. As shown in Figure 3 and 4, the lower the pH at 70 ℃ temperature allulose content was reduced, the production amount of the allulose conversion was increased.

Therefore, allulose is unstable at lower pH and at higher temperature, so that the content of allulose is changed in the actual production process, especially in the concentration step. This problem lowers the high purity allulose purity and has a great influence on the crystallization step. In fact, as the content of allulose is reduced in this process, the content of a specific allulose conversion (Impurity) that is additionally produced increases, and it was confirmed that this component has a great influence on the crystallization of allulose. If the content of more than 2% of Impurity-S is present in various allulose conversions, it can be seen that it acts as a major obstacle to the growth of allulose crystal grains. It was confirmed that it affects.

Experimental Example  3: Allulose  Characterization of Crystals

 (1) grain size distribution analysis

The particle size distribution of allulose crystals obtained in Example 5 was confirmed using a standard mesh for each mesh. The mesh size of the standard mesh was 20, 30, 40, 60, 80, 100 mesh, and the size distribution of the crystal grains was measured by the size of the hole of the standard mesh.

The hole sizes of the standard meshes for each mesh are 850, 600, 425, 250, 180 and 150 μm. 100g of each sample was taken and placed in a standard mesh for each mesh size, and vibration was applied for 3 minutes to pass the standard mesh. Percentage values of the samples remaining in the sieve were weighed for each mesh size. Table 4 shows the particle size distribution for each mesh.

Mesh size 100 mesh pass 100 mesh ↑ 80 mesh ↑ 60 mesh ↑ 40 mesh ↑ 30 mesh ↑ 20 mesh ↑ Particle Size (㎛) ≤150 150 < 180 < 250 < 425 < 600 < 850 < Example 5 0.9 2.6 5.9 20.2 70.0 0.4 0

As shown in Table 4, the allulose crystals of Example 5 had a very narrow distribution with a concentration of 90.2% by weight of particles, and the allulose crystals of Example 3 showed the largest distribution at 40 40. It was confirmed that the particle distribution was widely spread, evenly distributed at 80 ↑, 60 ↑, 40 ↑, and 30 ↑. As in Example 5, it was confirmed that the smaller the solid diameter / short diameter ratio and the harder the crystal grain, the lower the fine content of the product and the uniform particle size distribution. In addition, as the ratio of the long diameter to the short diameter is high and low, the uniformity of particles may be undifferentiated by the cracking of particles during drying and conveyance, and thus may have a wide range of particle size distribution.

(2) crystal form and grain size analysis

The optical photomicrograph measured by the magnification X100 of the allulose crystal obtained in Example 5 is shown in FIG. The scanning electron microscope (SEM) photograph measured by the magnification X100 of the allulose crystal obtained in Example 5 is shown in FIG.

Moreover, the long diameter (vertical) and the short diameter (horizontal) were measured about nine samples of the allulose crystals obtained in Example 5, and the particle diameter ratio (= long diameter / short diameter) was obtained and shown in Table 5 below. Specifically, for the five crystals, the ratio of the length (μm) of the long diameter was shown based on the short diameter length (μm) as one.

decision Example 5 #One 1.3 #2 1.5 # 3 1.2 #4 1.2 # 5 2.1 # 6 1.7 # 7 1.7 #8 1.4 # 9 2.4 Average 1.6

As shown in FIG. 6, the allulose crystal according to the present invention has a rectangular hexahedron or a crystal structure close thereto. The ratio of the length (μm) of the long diameter shown on the basis of the short diameter length (μm) of the crystals shown in Table 2 is 1, in the case of Example 5 It forms a crystalline form. In addition, it can be seen that as the crystal surface grows uniformly, the ratio of long diameter to short diameter tends to decrease. It is interpreted that the lower the allulose purity of the crystallization raw material, the more influenced the crystal shape because other ingredients other than allulose acts as an impediment to the crystal growth of pure allulose.

(3) Differential Scanning Calorimetry (DSC) Analysis

DSC analysis of the allulose crystals obtained in Example 5 was carried out. Specific DSC analysis conditions are as follows.

Equipment Name: DSC [differential scanning calorimetry]

Manufacturer: Perkin Elmer

Method: 30-250 ° C., 10 ° C./min elevated temperature, N2 gas purge

(Standard method: refer to ASTM D 3418)

DSC analysis results of the allulose crystals are shown in Table 6 below.

division Tm (?) ? H (J / g) Example 5 127.89 207.5

As a result of the DSC analysis, the crystal of Example 5 had a high Tm value and a high heat capacity. In the DSC analysis of the crystals, it can be predicted that the higher the heat capacity, the easier it is to melt, and the higher the heat capacity and the narrower the endothermic peak, the more uniform and hard the crystal is formed. Considering the heat capacity and endothermic peak enthalpy value of Example 5, it was confirmed that the crystal of Example 5 was formed more uniformly and harder.

(4) IR absorption spectrum analysis

In order to confirm the prepared allulose crystals, infrared absorption (IR) spectrum analysis was performed on the crystals of Example 5 under the following measurement conditions.

Analytical instrument: TENSOR II with Platinum ATR, manufacturer; Bruker (German)

Detector: highly sensitive photovoltaic MCT detector with liquid nitrogen cooling.

Scan count: 64 scans at 20 kHz

Scan range: 800-4,000 cm-1 and averaged at 4 cm-1 resolution.

Infrared absorption (IR) spectral analysis results show that allulose molecules have unique structural properties because they are composed of functional groups -OH, COC, CC, and C-OH in the allulose molecular structure. The crystal of Example 5 was confirmed to be the same allulose crystal. The IR analysis spectrum is shown in FIG. 7.

(5) X-ray diffraction analysis (XRD) analysis

The allulose crystals obtained in Example 5 were subjected to X-ray diffraction analysis according to the following specific analysis conditions, and the X-ray diffraction analysis results of the allulose crystals obtained in Example 5 were characterized by five peaks and shape specificities. Peaks are selected and shown in Table 7.

Analyzer: D / MAX-2200 Ultima / PC

Manufacturer: Rigaku International Corporation (Japan)

X-ray sauce system target: sealed tube Cu

Tube voltage: 45 kV / Tube current: 200 mA

Scan range: 5 to 80 ° 2θ

Step size: 0.019 °

Scan speed: 5 ° / min

Angle 2-Theta degree Relative Intensity% 18.78 100.0 15.24 97.6 28.37 9.5 30.84 18.8 31.87 9.0 47.06 4.1

As shown in Table 7, the allulose crystals obtained in Example 5 had Angle 2-Theta degree values of 15.24, 18.78 and 30.84 on powder X-ray spectral spectra; 15.24, 18.78, 30.84, and 28.37; 15.24, 18.78, 30.84 and 31.87; 15.24, 18.78, 30.84 and 47.06; Or 15.24, 18.78, 30.84, 28.37, 31.87 and 47.06.

Claims (35)

Providing an allulose composition for crystallization containing allulose; And cooling the crystallization allulose composition to produce allulose crystals.
Providing the crystallization allulose composition is to adjust the content of the allulose conversion based on the total solids content contained in the crystallization allulose composition to 2% by weight or less,
The allulose conversion is that containing an allulose modified polymer having a molecular weight of 1.5 to 10 times the allulose molecular weight,
Process for preparing allulose crystals. The method of claim 1, wherein the allulose conversion is a material having a ratio of mass / charge measured by LC / MS analysis in the range of 300 to 400 m / z. The method of claim 1, wherein the allulose conversion is a material having a maximum peak measured in a dissolution time of 31 minutes ± 2 minutes by analysis by HPLC analysis. The method of claim 1, wherein the step of providing the crystallization allulose composition is carried out by adjusting one or more conditions selected from the group consisting of pH conditions and temperature conditions, the content of the allulose conversion is less than 2% by weight To provide a chemical allulose composition,
Wherein the pH conditions range from pH 4 to 7 and the temperature conditions are at least 40 ° C. and less than 70 ° C. The method of claim 1, wherein the allulose crystal yield is at least 55%. delete The method of claim 1, wherein the allulose composition for crystallization, the method comprising 90% by weight or more of allulose based on the total solid content contained in the composition. The method of claim 1, wherein the preparing of the allulose crystals comprises: stirring the crystallized allulose composition at a temperature of 20 to 40 ° C. to generate crystal nuclei, and cooling the temperature of the composition to grow the crystals. Comprising. The method of claim 8, wherein the preparing of the allulose crystals further comprises increasing the temperature of the crystallization allulose composition to a range of 30 to 35 ° C. to redissolve the crystals produced during cooling. How. The method of claim 8, wherein the method further comprises adding a seed. The method of claim 1, wherein the allulose crystal yield is at least 45%. The method of claim 1, wherein the step of providing the crystallization allulose composition, by treating the allulose-containing reaction solution by SMB chromatography separation process, the allulose fraction obtained by concentrating at a temperature condition of less than 40 to 70 ℃ To perform. The method of claim 12, wherein the concentration process is performed discontinuously in at least two steps. The method of claim 12, wherein the activated carbon treatment process is further performed prior to performing the concentration process. The method of claim 1, wherein the step of providing the allulose composition for crystallization is to provide a solution in which allulose crystals or powders are dissolved in water. The method of claim 15, wherein the allulose crystal is a crystal obtained by crystallizing a concentrate obtained by concentrating an allulose fraction obtained by an SMB chromatography separation process. The content of allulose is 90% by weight or more based on the total solid content and the content of allulose conversion (Impurity-S) is 2% by weight or less.
The allulose conversion is that containing an allulose modified polymer having a molecular weight of 1.5 to 10 times the allulose molecular weight,
Allulose crystallization composition. The composition of claim 17, wherein the composition for allulose crystallization has a viscosity of 2 cps to 200 cps at a temperature of 45 ° C. 18. The composition of claim 17, wherein the composition for allulose crystallization has an electrical conductivity of 1,000 uS / cm or less. The composition of claim 17, wherein the allulose conversion (Impurity-S) is a substance having a ratio of the mass / charge amount measured by LC / MS analysis in the range of 300 to 400 m / z. 18. The composition for crystallization of allulose according to claim 17, wherein the allulose converting material is a substance having a maximum peak measured in a dissolution time of 31 minutes ± 2 minutes by HPLC analysis. The composition of Claim 17 whose yield of the allulose crystal obtained by crystallization of the said allulose crystallization composition is 55% or more. The composition of claim 17, wherein the composition has a pH of 4 to 7. The composition for crystallization of allulose according to claim 17, wherein the composition is adjusted to a temperature of 40 ° C or higher to less than 70 ° C. It comprises the step of adjusting the content of the allulose conversion (Impurity-S) contained in the composition for allulose crystallization to less than 2% by weight based on the solid content,
The allulose conversion (Impurity-S) is that containing an allulose modified polymer having a molecular weight of 1.5 to 10 times the allulose molecular weight,
Method for producing an allulose composition for crystallization. The method of claim 25, wherein the method is performed by adjusting one or more conditions selected from the group consisting of pH conditions and temperature conditions,
Wherein the pH conditions range from pH 4 to 7 and the temperature conditions are at least 40 ° C. and less than 70 ° C. The method of Claim 25 whose yield of the allulose crystal obtained by crystallization of the said composition for allulose crystallization is 55% or more. delete The method of claim 25, wherein the allulose crystallization composition is prepared by treating the allulose-containing reaction solution by an SMB chromatography separation process and concentrating the obtained allulose solution at a temperature condition of less than 40 to 70 ℃. Way. 30. The method according to claim 29, wherein the concentration process is performed discontinuously by dividing into at least two stages, the concentration of the allulose crystallization composition to 30 ~ 50Bx concentration is carried out first, and the primary concentrate is again 60 ~ 85Bx Second concentration to concentration. 30. The method of claim 29, further comprising performing an activated carbon treatment process prior to performing the concentration process. The method according to claim 25, wherein the allulose crystallization composition is provided as a solution in which allulose crystals or powders are dissolved in water. The method of claim 25, wherein the composition for crystallization of allulose has an electrical conductivity of 1,000 uS / cm or less. delete delete

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