Crystalline psicose

Abstract

The present application relates to: a crystalline psicose exhibiting an X-ray powder diffraction pattern in which peaks appear at 2 [theta] diffraction angle positions of 18.8 + / -0.5 DEG, 15.2 + / -0.5 DEG, and 19.5 + / -0.5 DEG in X-ray powder diffraction (XRD) analysis; a sweetener composition containing a crystalline psicose; and a method for preparing crystalline psicose.

Description

Technical Field

[0001] The present application relates to an allulose crystal. Background Art

[0002] Allulose is a functional sweetener that can replace sugar or fructose, etc., but there are the following problems: it is difficult to prepare allulose in a uniform and crystalline form due to its low crystallinity, and when it is prepared in a crystalline form, caking occurs due to rapid changes in temperature and humidity during the storage of allulose crystals. In particular, in the case of paper bag packaging containing allulose crystals, there are the following problems: namely, surface caking where crystal particles flocculate with each other under the moisture and pressure in the atmosphere will be further accelerated, and when surface caking starts, the caking hardness will further increase during long-term loading. Such high caking hardness makes the use of the product very limited.

[0003] Therefore, there is a need for a new type of allulose crystal with improved usability, in which caking during long-term storage is suppressed, and which has low hygroscopicity and excellent fluidity. Summary of the Invention

[0004]

Technical Problem

[0005] One embodiment of the present application is to provide an allulose crystal having a specific diffraction angle pattern.

[0006] Another embodiment of the present application is to provide a sweetener composition comprising an allulose crystal having a specific diffraction angle pattern.

[0007] Another embodiment of the present application is to provide a method for preparing an allulose crystal having a specific diffraction angle pattern, which includes adding seeds to an allulose solution by controlling the total specific surface area of all the seeds contained in the crystallization reaction system; and forming allulose crystals while controlling the supersaturation of the allulose solution.

[0008]

Technical Solution

[0009] One embodiment of the present application relates to an allulose crystal having an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8±0.5°, 15.2±0.5°, and 19.5±0.5° in X-ray powder diffraction (XRD) analysis.

[0010] Another embodiment of the present application relates to a sweetener composition comprising an allulose crystal according to one embodiment of the present application.

[0011] Another embodiment of the present application relates to a method for preparing psicose crystals according to an embodiment of the present application, which includes the step of adding seed crystals to a psicose solution so that the total specific surface area of all the seed crystals contained in the crystallization reaction system is 0.05 m 2 or less per 100 g; and the step of forming psicose crystals while maintaining the supersaturation of the psicose solution at 1.15 or less.

[0012] Hereinafter, the present application will be described in more detail.

[0013] Psicose crystals according to an embodiment of the present application may have an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8 ± 0.5°, 15.2 ± 0.5°, and 19.5 ± 0.5° in X-ray powder diffraction (XRD) analysis. Specifically, the psicose crystals may have an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8 ± 0.2°, 15.2 ± 0.2°, and 19.5 ± 0.2° in X-ray powder diffraction (XRD) analysis.

[0014] As an embodiment, the psicose crystals may have an X-ray powder diffraction (XRD) pattern that includes peaks at 2θ diffraction angles of 18.8 ± 0.5°, 15.2 ± 0.5°, 19.5 ± 0.5°, and 28.4 ± 0.5°, or 18.8 ± 0.5°, 15.2 ± 0.5°, 19.5 ± 0.5°, and 20.3 ± 0.5° in X-ray powder diffraction analysis.

[0015] As an embodiment, the psicose crystals may have an X-ray powder diffraction (XRD) pattern that includes peaks at 2θ diffraction angles of 18.8 ± 0.2°, 15.2 ± 0.2°, 19.5 ± 0.2°, and 28.4 ± 0.2°, or 18.8 ± 0.2°, 15.2 ± 0.2°, 19.5 ± 0.2°, and 20.3 ± 0.2° in X-ray powder diffraction analysis.

[0016] The peaks may be peaks with a relative intensity of 5% or more, 6% or more, 7% or more, 10% or more, 11% or more, 12% or more, 15% or more, 17% or more, 18% or more, 20% or more, 25% or more, 30% or more, 34% or more, 35% or more, 40% or more, 45% or more, 50% or more, 60% or more, 65% or more, 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more in the X-ray powder diffraction (XRD) analysis results. Based on 100% of the intensity of the peak with the maximum intensity, the relative intensity shows the intensity of each peak as a relative numerical percentage.

[0017] Among these peaks, several peaks with the highest relative intensity, or peaks with a relative intensity higher than a certain value, may be the main peaks determining the crystal form. For example, the main peaks may be 1 to 5, 1 to 4, 1 to 3, or 1 to 2 peaks with the highest relative intensity. For example, the main peaks may be peaks with a relative intensity of more than 50%, more than 55%, or more than 60%.

[0018] Therefore, the diffraction angle of the above-mentioned psicose crystal can be the diffraction angle at the main peak with a high relative intensity in X-ray powder diffraction (XRD) analysis, and the description order of the diffraction angles can be described starting from the diffraction angle with the highest relative intensity in X-ray powder diffraction (XRD) analysis.

[0019] As an embodiment, the psicose crystal may have an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8 ± 0.5°, 15.2 ± 0.5°, and 19.5 ± 0.5° in the order from the peak with a relatively higher intensity to the peak with a relatively lower intensity in X-ray powder diffraction (XRD) analysis. Specifically, the psicose crystal may have an X-ray powder diffraction pattern that includes characteristic peaks at 2θ diffraction angle positions of 18.8 ± 0.2°, 15.2 ± 0.2°, and 19.5 ± 0.2° in the order from the peak with a relatively higher intensity to the peak with a relatively lower intensity in X-ray powder diffraction (XRD) analysis.

[0020] As an embodiment, the psicose crystal may have an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8 ± 0.5°, 15.2 ± 0.5°, 19.5 ± 0.5°, and 28.4 ± 0.5° in the order from the peak with a relatively higher intensity to the peak with a relatively lower intensity in X-ray powder diffraction (XRD) analysis. Specifically, the psicose crystal may have an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8 ± 0.2°, 15.2 ± 0.2°, 19.5 ± 0.2°, and 28.4 ± 0.2° in the order from the peak with a relatively higher intensity to the peak with a relatively lower intensity in X-ray powder diffraction (XRD) analysis.

[0021] As an embodiment, the psicose crystal may have an X-ray powder diffraction pattern that, in X-ray powder diffraction (XRD) analysis, includes peaks at 2θ diffraction angle positions of 18.8 ± 0.5°, 15.2 ± 0.5°, 19.5 ± 0.5°, and 20.3 ± 0.5° in order from the peak with higher relative intensity to the peak with lower relative intensity. Specifically, the psicose crystal may have an X-ray powder diffraction pattern that, in X-ray powder diffraction (XRD) analysis, includes peaks at 2θ diffraction angle positions of 18.8 ± 0.2°, 15.2 ± 0.2°, 19.5 ± 0.2°, and 20.3 ± 0.2° in order from the peak with higher relative intensity to the peak with lower relative intensity.

[0022] As an embodiment, the psicose crystal may have an X-ray powder diffraction pattern in which, in X-ray powder diffraction (XRD) analysis, the peak with the highest relative intensity is located at a 2θ diffraction angle of 18.8 ± 0.5° or 18.8 ± 0.2°.

[0023] The psicose crystal according to an embodiment of the present application has a low specific surface area and a high tap density. Therefore, the friction between particles is reduced, so the particles are more likely to move, and its volume is more likely to decrease when stacked, which is beneficial for storage and distribution.

[0024] The psicose crystal according to an embodiment of the present application has a low surface caking hardness increase rate and a low moisture absorption rate, and thus has high storage stability. In the case of the product surface where the packaging material contacts the product in the packaged product, due to the rapid change of temperature and humidity according to the storage conditions, a surface caking effect may occur. In particular, in the case of loading in a paper bag packaging, caking may be further accelerated, and once the surface caking starts, the caking hardness may be further enhanced during long-term loading. In the examples of the present application, as a result of measuring the increase rates of caking hardness and moisture absorption rate by reproducing the situation where the psicose crystal according to an embodiment of the present application is exposed to common storage conditions or the influence of outdoor air, its caking hardness and moisture absorption rate are lower than those of conventional psicose crystals.

[0025] In addition, the psicose crystal according to an embodiment of the present application has a high average particle size and a low angle of repose. Therefore, the crystal particles do not accumulate or stagnate and have good fluidity. Thus, it is easy to conduct pipeline transportation during the manufacturing process and can reduce losses in the dehydration / drying / cooling process line. In addition, the production speed is increased during the packaging process, and the frequency of packaging defects is reduced, thereby improving productivity and output throughout the production process.

[0026] The crystal form may vary due to the diffraction angle and relative intensity of peaks in the XRD analysis results. Therefore, the angle of repose of allulose crystals may be affected. For example, even if it is a peak at the same position of the 2θ diffraction angle in the X-ray powder diffraction (XRD) analysis, considering the relative intensity of the peak, the angle of repose may vary depending on the crystal orientation or crystal form.

[0027] The allulose crystals according to the present application may have a low angle of repose. For example, the angle of repose of allulose crystals can be 48° or less, 47° or less, 46° or less, 45° or less, 44° or less, 43° or less, or 42.5° or less, and in particular, it can be 37° to 48°, 37° to 47°, 37° to 46°, 37° to 45°, 37° to 44°, 37° to 43.5°, 37° to 43°, 37° to 42.5°, 40° to 48°, 40° to 47°, 40° to 46°, 40° to 45°, 40° to 44°, 40° to 43.5°, 40° to 43°, or 40° to 42.5°. In addition, based on 100% of the angle of repose of sugar, the angle of repose of allulose crystals can be 120% or less, 115% or less, 110% or less, 108% or less, 107% or less, or 106% or less, and it can be at a similar level to the angle of repose of sugar. At this time, based on 100% of the angle of repose of sugar, the lower limit of the angle of repose of allulose crystals can be, for example, 95% or more, 96% or more, 97% or more, 98% or more, 99% or more, 100% or more, greater than 100%, 101% or more, 102% or more, 103% or more, 104% or more, or 105% or more, but is not limited thereto. A low angle of repose indicates a low powder packing angle, meaning high fluidity. Therefore, the allulose crystals according to an embodiment of the present application have a uniform particle shape and thus have an excellent fluidity effect.

[0028] Specifically, the allulose crystals according to an embodiment of the present application may have at least one property selected from the group consisting of the following (1) to (5):

[0029] (1) A specific surface area of 0.04 m 2 / g or less, 0.035 m 2 / g or less, 0.03 m 2 / g or less, or 0.025 m 2 / g or less.

[0030] (2) A volume average particle diameter (D[4,3]) of 230 μm or more, 240 μm or more, 250 μm or more, 260 μm or more, 270 μm or more, 280 μm or more, 290 μm or more, 300 μm or more, 310 μm or more, 320 μm or more, 330 μm or more, 340 μm or more, 350 μm or more, 360 μm or more, or 370 μm or more,

[0031] (3) An angle of repose of 48° or less, 47° or less, 46° or less, 45° or less, 44° or less, 43° or less, or 42.5° or less,

[0032] (4) A moisture absorption rate of 24% or less, 23% or less, 22% or less, or 21.5% or less when stored at a temperature of 25°C and a humidity of 70% for 15 hours, and

[0033] (5) When loaded and stored at a temperature of 40°C and a humidity of 70% for 0.5 hour, then left at a temperature of 25°C for 30 minutes, and a pressure equal to the weight of the allulose crystals is applied for 30 minutes, a hardness increase rate of 40% or less, 35% or less, 30% or less, 25% or less, or 20% or less.

[0034] The allulose crystals according to one embodiment of the present application may be those crystallized under the condition that the total specific surface area of all the seed crystals contained in the crystallization reaction system is 0.05 m 2 / 100g or less, 0.045 m 2 / 100g or less, 0.04 m 2 / 100g or less, 0.035 m 2 / 100g or less, or 0.03 m 2 / 100g or less.

[0035] The total specific surface area of all the seed crystals present in the crystallization reaction system can be obtained by multiplying the average specific surface area value (m 2 / g) of the seed crystal particles by the amount of seed crystal input (g / 100g). The total specific surface area of all the seed crystals can be set by adjusting one or more of the average specific surface area value of the seed crystal particles and the amount of seed crystal input. According to the examples of the present application, it was confirmed that due to the total specific surface area of all the seed crystals in the crystallization reaction system, the average diameter of the allulose crystals was stably greater than the particle size difference of the seed crystals added during the preparation of the allulose crystals, and due to the stacking and shape differences of the particles formed during the crystallization step, allulose crystals having a specific diffraction angle pattern were prepared, and the composition of the main peak of the X-ray diffraction angle was different from that of conventional allulose crystals.

[0036] The psicose crystals according to an embodiment of the present application may be crystallized under the condition that the supersaturation of the psicose solution is 1.15 or less, specifically, greater than 1 to 1.15 or less, or 1.01 or more to 1.15 or less. According to the examples of the present application, in the process of preparing psicose crystals, when the supersaturation of the psicose solution is greater than 1.15 and when the supersaturation is maintained at 1.15 or less, the X-ray powder diffraction patterns of the prepared psicose crystals are different. Therefore, the psicose crystals according to an embodiment of the present application are crystallized under the condition that the supersaturation of the psicose solution is 1.15 or less, and thus, in X-ray powder diffraction (XRD) analysis, it may have an X-ray powder diffraction pattern including peaks at diffraction angles of 2θ of 18.8 ± 0.5°, 15.2 ± 0.5°, and 19.5 ± 0.5°.

[0037] Another embodiment of the present application relates to a method for preparing psicose crystals, which includes the step of adding seed crystals to a psicose solution so that the total specific surface area of all the seed crystals contained in the crystallization reaction system is 0.05 m 2 / 100 g or less; and the step of forming psicose crystals while maintaining the supersaturation of the psicose solution at 1.15 or less.

[0038] The psicose solution for preparing psicose crystals is a high-purity psicose solution with a high psicose content, and based on 100% by weight of the solid content, it may have a psicose content of 80% by weight or more, 85% by weight or more, 90% by weight or more, 91% by weight or more, 92% by weight or more, 93% by weight or more, 94% by weight or more, or 95% by weight or more. In addition, the psicose solution may be a psicose solution with 80% or more, 85% or more, or 85% or more solids, which is concentrated and then used for crystallization.

[0039] The step of forming psicose crystals may be carried out by cooling the temperature of the psicose solution at a rate of -0.5 °C / hour (hr) or less, -0.4 °C / hr or less, or -0.3 °C / hr or less. At this time, the step of forming psicose crystals may control the cooling rate to control the supersaturation of the psicose solution. For example, in order to maintain the supersaturation in the psicose solution at 1.15 or less, it may include at least one or more steps of controlling the cooling rate of the psicose solution.

[0040] The supersaturation of the psicose solution is maintained below 1.15, and the cooling rate or the content of psicose solids in the psicose solution can be controlled. Controlling the cooling rate can specifically include the deceleration part of the cooling rate. For example, it can include controlling the cooling rate to 0 °C / hr, that is, stopping the cooling. Stopping the cooling can cause the cooling to stop until the supersaturation of the psicose solution becomes below 1.15. Therefore, controlling the cooling rate of the psicose solution can temporarily stop the cooling of the psicose solution. Specifically, it can temporarily stop the cooling of the psicose solution to keep the temperature of the psicose solution constant.

[0041] Therefore, in one embodiment of the present application, the step of forming psicose crystals while maintaining the supersaturation of the psicose solution below 1.15, or the step of controlling the cooling rate of the psicose solution so that the supersaturation of the psicose solution is maintained below 1.15, may include a first cooling section, a deceleration section of the cooling rate, and a second cooling section, and the deceleration section of the cooling rate may include at least one or more times, and this deceleration section can be executed until the supersaturation of the psicose solution becomes below 1.15. Specifically, the first cooling section can cool the psicose solution at a constant rate, and the cooling rate can be reduced in the deceleration section of the cooling rate, and when the supersaturation of the psicose solution becomes below 1.15, the second cooling section can be executed. The cooling rates of the first cooling section and the second cooling section can be the same or different.

[0042] For example, controlling the cooling rate of the psicose solution can temporarily stop the cooling when the temperature of the psicose solution is in the range of 15 - 45 °C, 15 - 40 °C, 15 - 39 °C, 15 - 38 °C, 20 - 45 °C, 20 - 40 °C, 20 - 39 °C, 20 - 38 °C, 25 - 45 °C, 25 - 40 °C, 25 - 39 °C, 25 - 38 °C, 30 - 45 °C, 30 - 40 °C, 30 - 39 °C, 30 - 38 °C, 35 - 45 °C, 35 - 40 °C, 35 - 39 °C, 35 - 38 °C, 36 - 45 °C, 36 - 40 °C, 36 - 39 °C, 36 - 38 °C, 37 - 45 °C, 37 - 40 °C, 37 - 39 °C, or 37 - 38 °C. At this time, the temperature of the psicose solution can be constantly maintained within the above range.

[0043] Specifically, the step of forming psicose crystals may include the step of maintaining the temperature of the psicose solution by stopping the cooling until the supersaturation of the psicose solution reaches below 1.1 when the supersaturation of the psicose solution is greater than 1.15.

[0044] The step of forming psicose crystals can start cooling the psicose solution when the supersaturation of the psicose solution is greater than 1 to below 1.15, or in the range of 1.01 to 1.15.

[0045] The step of forming allulose crystals may start cooling the allulose solution at a temperature of 25 - 50 °C, 30 - 50 °C, 35 - 50 °C, 40 - 50 °C, 25 - 45 °C, 30 - 45 °C, 35 - 45 °C or 40 - 45 °C.

[0046] The step of forming allulose crystals may terminate cooling the allulose solution when the temperature of the allulose solution is 15 - 25 °C, 15 - 23 °C, 15 - 20 °C, 18 - 25 °C, 18 - 23 °C or 18 - 20 °C.

[0047]

Beneficial effects

[0048] The allulose crystals according to an embodiment of the present application have different X - ray spectral compositions, and the final product has particles with a specific surface area value of 0.04 m 2 / g or less, a diameter of 230 μm or more, relatively uniform crystal shape and improved transparency, and have improved hygroscopicity and fluidity, and improved ease of use and reduced caking degree during storage, and the stability during the packaging, storage, transportation and distribution of the product is improved, and the usability during long - term storage is improved. In addition, the crystals themselves can reduce the bitterness and off - flavors previously felt after sweetness and obtain a taste similar to sugar. Description of the drawings

[0049] Figure 1a Showing the appearance of allulose crystals prepared without controlling the supersaturation and cooling rate of the allulose solution, Figure 1b Showing the appearance of allulose crystals according to an embodiment of the present application.

[0050] Figure 2 A graph showing the moisture absorption rate of allulose crystals according to an embodiment of the present application.

[0051] Figure 3 A graph showing the change rate of the caking hardness of allulose crystals according to an embodiment of the present application.

[0052] Figure 4 A sweetness curve graph for the sensory evaluation of allulose crystals according to an embodiment of the present application. Detailed description of the specific embodiments

[0053] Hereinafter, the present application will be described in more detail by the following examples. However, these examples are only intended to illustrate the present application, and the scope of the present application is not limited by these examples.

[0054] Comparative Example 1: Preparation of allulose crystals (1)

[0055] High-performance liquid chromatography (HPLC) analysis for the content of allulose was performed using an RI detector by setting the Biorad Carbohydrate Aminex HPX 87C column at a temperature of 80 °C and then setting the mobile phase to distilled water (DW) at 0.6 mL / min.

[0056] A high-purity allulose solution with a purity of 95 wt% was concentrated to a concentration of 87.2% in terms of solid content, and the temperature of the allulose solution was cooled from 35 °C to 10 °C at a rate of -1 °C / hr to form allulose crystals. At this time, the supersaturation of the initial crystallization solution was approximately 1.5, and no allulose seed crystals were added. The mother liquor was removed by centrifugal dehydration, and the allulose crystals were washed with cooling water and then dried to collect the allulose crystals. The average particle size of the initially obtained allulose crystals was 225 µm.

[0057] The obtained allulose crystals were pulverized by a hammer mill equipment to be used as seed crystals in the following examples. The average particle size of the allulose crystals in Comparative Example 1 was 62.5 µm, and the average specific surface area was 0.327 m 2 / g.

[0058] [Table 1]

[0059]

[0060] Comparative Example 2: Preparation of allulose crystals (2)

[0061] The separated high-purity allulose solution with a purity of 95 wt% was concentrated to a concentration of 85% in terms of solid content, and the temperature of the solution in the crystallization reactor was maintained at 50 °C. Seed crystals with an average particle size of 98.0 µm and an average specific surface area of 0.196 m 2 / g were mixed with ethanol and added at a concentration of 0.3%, and then evenly distributed. At this time, the supersaturation of the initial crystallization solution was 1.39, and for crystallization, the cooling temperature was cooled to 30 °C at a rate of -1 °C / hr per hour. The mother liquor was removed by centrifugal dehydration, and the crystals were washed with cooling water and then dried to collect the obtained allulose crystals.

[0062] The physical properties of the prepared allulose crystals are described in Table 1. The particle size of the allulose crystals in Comparative Example 2 was an average particle size of 154.04 µm, and the average specific surface area was 0.0558 m 2 / g.

[0063] Comparative Example 3: Preparation of allulose crystals (3)

[0064] A high-purity psicose solution with a purity of 95% by weight was concentrated to a concentration of 86.1% by solid content, and the temperature of the concentrated psicose solution was adjusted to 44.5 °C so as to set the supersaturation of the psicose solution to 1.05. The crushed crystals prepared in Comparative Example 1 were added to the psicose solution at a concentration of 1.7% by weight as seed crystals, and stirred to be uniformly distributed, and then the crystallization process was prepared. At this time, the total specific surface area of the added seed crystals was 0.327 m 2 / g × 1.7 g / 100g ≒ 0.556 m 2 / 100g.

[0065] Thereafter, psicose crystals were produced while keeping the temperature of the psicose solution constant at a rate of -0.3 °C / hr. At this time, the cooling rate was not controlled to keep the supersaturation of the psicose solution constant, but was cooled at a constant rate until the final temperature reached 20 °C. During the crystallization process, the supersaturation increased to 1.19. The mother liquor was removed by centrifugal dehydration, and the crystals were washed with cooling water and then dried to collect the psicose crystals.

[0066] The physical properties of the prepared psicose crystals are described in Table 1. The average particle size of the psicose crystals in Comparative Example 3 was 165.6 µm, and the specific surface area value was 0.0513 m 2 / g. The appearance of the prepared psicose crystals is as Figure 1a shown.

[0067] Comparative Example 4: Preparation of Psicose Crystals (4)

[0068] A high-purity psicose solution with a purity of 95% by weight was concentrated to a concentration of 86.3% by solid content, and the temperature of the concentrated psicose solution was adjusted to 45 °C so as to set the supersaturation of the psicose solution to 1.057. Psicose crystals with a purity of 99%, an average diameter of 189.5 µm, and an average specific surface area of 0.040 m 2 / g were added to the psicose solution at a concentration of 2.0% by weight as seed crystals, and stirred to be uniformly distributed, and then the crystallization process was prepared. The total specific surface area of the seed crystals was 0.040 m 2 / g × 2.0 g / 100g ≒ 0.080 m 2 / g.

[0069] Thereafter, allulose crystals were produced while maintaining the temperature of the allulose solution constant and cooling it at a rate of -0.3 °C / hr. At this time, the cooling rate was not controlled to keep the supersaturation of the allulose solution constant, but rather it was cooled at a constant rate until the final temperature reached 20 °C. During the crystallization process, the supersaturation increased to 1.213. The mother liquor was removed by centrifugal dehydration, the crystals were washed with cooling water, and then dried to collect the allulose crystals.

[0070] The physical properties of the prepared allulose crystals are described in Table 1. The average diameter of the allulose crystals in Comparative Example 4 was 227.8 µm, and the specific surface area value was 0.0410 m 2 / g.

[0071] Example 1: Preparation of Allulose Crystals (5)

[0072] A high-purity allulose solution with a purity of 95 wt% was concentrated to a concentration of 85.4% by solid content, and the temperature of the concentrated allulose solution was adjusted to 44.2 °C in order to set the supersaturation of the allulose solution to 1.011. Allulose crystals with a purity of 99%, an average diameter of 189.5 µm, and an average specific surface area of 0.040 m 2 / g were added to the allulose solution at a concentration of 1.0 wt% as seeds, and stirred to be evenly distributed, and then the crystallization process was prepared. At this time, the total specific surface area sum of the seeds was 0.040 m 2 / g × 1.0 g / 100g ≒ 0.040 m 2 / 100g.

[0073] Thereafter, allulose crystals were produced while maintaining the temperature of the allulose solution constant and cooling it at a rate of -0.3 °C / hr. At this time, in order to keep the supersaturation in the allulose solution below 1.15, the supernatant was extracted from the allulose solution and its concentration was measured, and then the cooling was stopped at around 38 °C, where the supersaturation became 1.145, and kept at a constant temperature until the supersaturation reached 1.1 or below, and then cooled again after checking that the supersaturation value of the supernatant dropped to 1.082. Thereafter, when the temperature of the allulose solution was cooled to 20 °C, the supersaturation only increased to 1.131, and when the supersaturation no longer increased, the crystallization reaction terminated. The mother liquor was removed by centrifugal dehydration, the crystals were washed with cooling water, and then dried to collect the allulose crystals.

[0074] The physical properties of the prepared allulose crystals are described in Table 1. The average diameter of the allulose crystals in Example 1 was 282.7 µm, and the specific surface area value was 0.0298 m 2 / g. Compared with Comparative Example 4, the allulose crystals in this Example showed a relatively uniform particle distribution and a lower specific surface area.

[0075] Example 2: Preparation of Allulose Crystals (6)

[0076] A high-purity allulose solution with a purity of 95% by weight was concentrated to a concentration of 85.6% by solid content, and the temperature of the concentrated allulose solution was adjusted to 44.7 °C, and the supersaturation of the allulose solution was set to 1.01. The allulose crystals prepared in Comparative Example 2 were added to the allulose solution at a concentration of 0.5% by weight as seed crystals and stirred to be uniformly distributed, and then the crystallization process was prepared. The total specific surface area sum of the seed crystals was 0.0558 m 2 / g × 0.5 g / 100g ≒ 0.0279 m 2 / g.

[0077] Thereafter, allulose crystals were produced while keeping the temperature of the allulose solution constant at a rate of -0.3 °C / hr. At this time, in order to keep the supersaturation of the allulose solution below 1.15, the supernatant was taken out from the allulose solution and its concentration was measured, and then the cooling was stopped at around 38 °C, where the supersaturation became 1.145, and it was kept at a constant temperature until the supersaturation reached 1.1 or less, and then the cooling was resumed when the supersaturation value of the supernatant was 1.091. When the temperature of the allulose solution dropped below 25 °C, a section where the supersaturation gradually increased to 1.144 was shown, so the crystallization did not terminate at a temperature of 20 °C. After maintaining for a period of time, the supersaturation was reduced to 1.110 again, and the crystallization reaction terminated. The mother liquor was removed by centrifugal dehydration, the crystals were washed with cooling water, and then dried to collect the allulose crystals.

[0078] The physical properties of the prepared allulose crystals are described in Table 1. The average diameter of the allulose crystals in Example 2 was 378.4 µm, and the specific surface area value was 0.0203 m 2 / g. The appearance of the prepared allulose crystals is as Figure 1b shown.

[0079] Test Example 1: Identification of Allulose Crystal Forms

[0080] For the allulose crystals obtained in Comparative Examples 1 to 2 and Examples 1 to 2, X-ray diffraction analysis was performed according to the following analysis conditions, and the main peaks of the X-ray diffraction patterns of the allulose crystals are described in Table 2 in the order of relative intensity (%).

[0081] Analytical instrument: D / MAX-2200 Ultima / PC

[0082] Manufacturer: Rigaku International Corporation (Japan)

[0083] X-ray source system target: sealed tube Cu

[0084] Tube voltage: 45 kV / Tube current: 200 mA

[0085] Scanning range: 5 to 80° 2θ

[0086] Step size: 0.01°

[0087] Scanning speed: 5° / min

[0088] [Table 2]

[0089]

[0090] As shown in Table 2, the psicose crystals according to an embodiment of the present application have a specific diffraction angle pattern different from that of conventional psicose crystals.

[0091] Specifically, in the X-ray diffraction pattern of the psicose crystals according to Comparative Example 1, the diffraction angles (2θ) of the main peaks are shown in the order of relative intensity as 15.35°, 18.83°, 30.95° and 47.15°. The main peaks of the XRD diffraction angles of the initially obtained psicose crystals and the crushed crystals in Comparative Example 1 are the same, which means that even by changing the external shape of the crystal particles by crushing or the like, the crystal particles formed during the crystallization process maintain the same crystal form.

[0092] In addition, in the X-ray diffraction pattern of the psicose crystals according to Comparative Example 2, the diffraction angles (2θ) of the main peaks are shown in the order of relative intensity as 15.2°, 18.8°, 30.8° and 29.7°. In addition, in the X-ray diffraction pattern of the psicose crystals according to Comparative Example 3, the diffraction angles (2θ) of the main peaks are shown in the order of relative intensity as 15.2°, 18.8°, 30.8° and 28.3°. In addition, in the X-ray diffraction pattern of the psicose crystals according to Comparative Example 4, the diffraction angles (2θ) of the main peaks are shown in the order of relative intensity as 15.2°, 18.8°, 30.8° and 19.5°.

[0093] On the other hand, in an embodiment of the present application, in the X-ray diffraction pattern of the psicose crystals according to Example 1, the diffraction angles of the main peaks are shown as 18.8°, 15.2°, 19.5° and 28.4°, and there are differences in the relative intensity values of the main peaks compared with the X-ray diffraction pattern of the conventionally prepared psicose crystals.

[0094] In addition, in the X-ray diffraction pattern of the allulose crystal of Example 2 according to an embodiment of the present application, the diffraction angles (2θ) of the main peaks are shown as 18.8°, 15.2°, 19.5°, and 20.3°. Similar to Example 1, there are differences in the intensity values of the main peaks compared with the X-ray diffraction pattern of the conventionally prepared allulose crystal. In the X-ray diffraction analysis results of the allulose crystal, the diffraction angle (2θ) of the peak, the order of the diffraction angles of the peaks according to the relative intensity, etc. will affect the orientation characteristics and the angle of repose of the crystal, etc., so the shape, structure, and orientation of the allulose crystal may be different.

[0095] Test Example 2: Analysis of the Appearance Characteristics of the Prepared Allulose Crystal

[0096] The brightness (L value), redness (a value), yellowness (b value), and whiteness of the allulose crystals prepared in Comparative Examples 3 to 4 and Examples 1 to 2 were measured using a color difference meter (spectrophotometer SA-2000, Nippon Denshoku Industries co., Ltd.) and a whiteness measuring instrument (whiteness tester C-130, KETT electric laboratory), and are described in Table 3.

[0097] [Table 3]

[0098]

[0099] The closer to white, the higher the whiteness value. Generally, the whiteness level shown by sugar is between 80 and 86. In the case of containing a large amount of fine powder or particles with a dull surface, or in the case of rice (depending on the growing environment), when the starch granules are not densely packed and milky white rice grains are formed by loose rice grains, the whiteness value may further increase due to the difference in light scattering. Compared with Comparative Examples 3 and 4, the crystals of Examples 1 and 2 showed a whiteness level similar to that of sugar, and showed differences in color values, such as a lower yellowness (b value) measured in the color difference value analysis, etc. It can be inferred from the high yellowness that during the dehydration and washing process after crystallization, the mother liquor of the crystal may adhere to the crystal particles, and when a very small amount of the crystal mother liquor remains in the particles, it can also induce color browning or promote caking during long-term storage. The allulose crystal according to an embodiment of the present application shows a lower yellowness, which means that the formation of the crystal particles is uniform, so the washing is carried out smoothly during the dehydration process.

[0100] Test Example 3: Analysis of the Particle Characteristics of Allulose Crystal

[0101] For the allulose crystals obtained in Comparative Examples 1 to 4 and Examples 1 to 2, the average diameter and diameter distribution were measured using a diameter analysis device in the laser diffraction method, and the measured specific surface area is described in Table 1.

[0102] - Particle size analysis equipment: Laser diffraction particle analyzer, Mastersizer 2000 (MALVERN Panalytic Ltd.)

[0103] - Dispersion device: Hydro 2000 MU (wet type)

[0104] - Dispersion solvent: Isopropyl alcohol

[0105] As shown in Table 1, the allulose crystals according to an embodiment of the present application have a large size with an average diameter of 230 μm or more, and have an extremely low specific surface area of 0.04 m 2 / g or less.

[0106] Test Example 4: Measurement of the flowability of allulose crystals

[0107] For each of the allulose crystal samples obtained in Comparative Examples 3 to 4 and Examples 1 to 2, 150 g was prepared, and the angle of repose was measured using an automatic stirring type angle of repose measuring device (manufacturer: K-one Nano., Ltd., model name: BT-200DA). The allulose crystal powder sample was passed through a special funnel fixed at a certain height on a completely flat reference plate of the measuring device in a certain volume, and the angle of repose of the conical shape accumulated on the reference plate was measured. The results are shown in Table 4. In addition, based on 100% of the angle of repose of sugar, the angle of repose was converted into a relative angle of repose value and is shown in Table 4.

[0108] [Table 4]

[0109]

[0110] As shown in Table 4, it was confirmed that the allulose crystals according to an embodiment of the present application have improved particle flowability compared with conventional allulose crystals, and have an angle of repose at a similar level to sugar. Therefore, the convenience of use is increased in cases such as inputting crystal products or pipeline transfer.

[0111] Test Example 5: Comparison of the hygroscopicity of allulose crystals

[0112] The allulose crystal samples prepared in Comparative Examples 1 to 3 and Example 2 were accurately weighed 10 g each, and were uniformly dispersed on a weighing dish for preparation. By storing in a thermo-hygrostat at a temperature of 25 °C and a humidity of 70%, the weight of the sample was measured over time, and the weight increase due to hygroscopicity compared to the initial weight was calculated and shown as a percentage in Table 5 and Figure 2 in.

[0113] [Table 5]

[0114]

[0115] As shown in Table 5 and Figure 2 as shown, the psicose crystals according to an embodiment of the present application have improved hygroscopicity, and thus, they can maintain stability during product packaging and distribution.

[0116] Test Example 6: Determination of the Caking Hardness of Psicose Crystals

[0117] 25 g of the psicose crystal samples prepared in Comparative Examples 1 to 3 and Example 2 were respectively placed on the same aluminum plate having a uniform surface without applying an external pressure. When stored under constant temperature and humidity conditions of maintaining a temperature of 40 °C and a relative humidity of 70%, each sample was taken out at 0 hour and 30 minutes of storage, placed at room temperature (25 °C) for 30 minutes to cool the heat, and then weights (25 g) having the same weight as the sample were placed on the surface of the sample in the same manner for 30 minutes, and caking on the surface of the psicose crystals was induced. Specifically, by applying pressure to the surface using a weight having the same weight as the psicose crystal sample, the caking phenomenon that may occur during the loading and storage of psicose crystals can be reproduced. The caking hardness measurement conditions are as follows:

[0118] - Equipment name: Texture Analyzer TAXTplus (Stable Micro Systems)

[0119] - Cylindrical probe: 25 mmφ Perspex

[0120] - Test speed: 2 mm / sec

[0121] - Trigger force: 5 g

[0122] The caking hardness of each sample over time is shown in Table 6 and Figure 3 below.

[0123] [Table 6]

[0124]

[0125] As shown in Table 6 and Figure 3As shown, the surface caking hardness of the allulose crystals of Example 2 is the lowest, and the change in surface caking hardness is also the smallest even with the passage of time under high-temperature and moisture-absorbing conditions. On the other hand, the allulose crystals of Comparative Examples 1 to 3 with different specific surface areas of the particles showed a significant increase rate in caking hardness and an initial caking hardness. Therefore, when stored for a long time, due to the greater influence of the external environment and the larger storage load, the surface caking of the product may accelerate. It is confirmed that in the allulose crystal sample according to an embodiment of the present application, even under harsh storage conditions, the degree of surface caking is reduced, thereby improving the storage stability. Therefore, it can significantly help to improve the storage stability during the packaging, storage, transportation, and distribution processes of industrial products.

[0126] Test Example 7: Sensory Evaluation of Allulose Crystals

[0127] For the sensory evaluation, allulose crystal samples prepared in Comparative Examples 1 to 3 and Example 2 were prepared in the same amount, and 15 panelists with in-depth knowledge of sensory testing and more than 10 years of sensory testing experience were selected. The samples were provided to the sensory testers individually and evaluated using a 5-point method. For sweetness and refreshingness, the higher the score, the "better" or "stronger" the sweetness or refreshingness. For bitterness and off-flavor / taste change, the lower the score, the weaker the bitterness or off-flavor / taste change, so it is "better", and the higher the score, the stronger the bitterness or off-flavor / taste change, so it is "worse".

[0128] Each sample was represented by a three-digit number randomly obtained using a random number table, and the presentation order of the samples was always randomly determined. Warm water was provided to the testers for rinsing their mouths together. The sensory testing room was maintained at a certain temperature (25 ± 1 °C) and had no odor.

[0129] Taking items such as sweetness, refreshingness, bitterness, off-flavor, and taste change as the sensory characteristics of allulose crystals, the evaluation content and method were evaluated, and the control sugar was provided as a reference sample together to give the reference values of the sensory items. The sensory items were compared and evaluated with the sugar using a 15-cm linear scale. The numerical values of the sensory evaluation results are shown in Table 7 below, and the sweetness curve graph of the sensory evaluation results is as Figure 4 shown.

[0130] [Table 7]

[0131]

[0132] As a result of sensory evaluation, sweetness was analyzed in the same manner as known sweetness and was lower than that of sugar. However, compared to the comparative example samples, the sweetness curve in Example 2 was shown to be similar to that of sugar. In particular, the comparative example samples of allulose crystal particles with a larger surface area had a higher intensity perceived sensorially compared to sugar and had poor sensory characteristics for bitterness and off-flavors / taste changes. On the other hand, it was confirmed that the allulose crystals according to one embodiment of the present application had a smaller specific surface area and had a texture very similar to that of sugar, and thus the intensity of off-flavors and taste changes perceived was minimal, and the bitterness was also improved.

Claims

1. An allulose crystal having an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8 ± 0.5°, 15.2 ± 0.5°, and 19.5 ± 0.5° in X-ray powder diffraction (XRD) analysis.

2. The allulose crystal according to claim 1, having an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8 ± 0.5°, 15.2 ± 0.5°, 19.5 ± 0.5°, and 28.4 ± 0.5° in X-ray powder diffraction (XRD) analysis.

3. The allulose crystal according to claim 1, having an X-ray powder diffraction pattern that includes peaks at 2θ diffraction angle positions of 18.8 ± 0.5°, 15.2 ± 0.5°, 19.5 ± 0.5°, and 20.3 ± 0.5° in X-ray powder diffraction (XRD) analysis.

4. The allulose crystal according to claim 1, wherein the peak is a peak with a relative intensity of 5% or more.

5. The psicose crystal according to claim 1, wherein the specific surface area of the psicose crystal is 0.04 m 2 / g or less.

6. The allulose crystal according to claim 1, wherein the D[4,3] (volume average particle size) of the allulose crystal is 230 μm or more.

7. The psicose crystal according to claim 1, wherein, Compared with the angle of repose of sugar, the angle of repose of the allulose crystal is 120% or less.

8. The allulose crystal according to claim 1, wherein the angle of repose of the allulose crystal is 48° or less.

9. The psicose crystal according to claim 1, wherein, When stored for 15 hours at a temperature of 25°C and a relative humidity of 70%, the moisture absorption rate of the allulose crystal is 24% or less.

10. The psicose crystal according to claim 1, wherein, When stored for 0.5 hours at a temperature of 40°C and a relative humidity of 70%, left at a temperature of 25°C for 30 minutes, and a pressure equal to the weight of the allulose crystal is applied for 30 minutes, the hardness increase rate of the allulose crystal is 40% or less.

11. The psicose crystal according to claim 1, wherein the psicose crystal is crystallized under the condition that the total specific surface area of all the seed crystals contained in the crystallization reaction system is 0.05 m 2 / 100 g or less.

12. The allulose crystal according to claim 1, wherein the allulose crystal is crystallized under the condition that the supersaturation of the allulose solution is 1.15 or less.

13. A sweetener composition comprising the allulose crystal according to any one of claims 1 - 12.

14. A method for preparing the allulose crystal according to any one of claims 1 - 12, comprising: The step of adding seeds to the psicose solution so that the total specific surface area of all the seeds contained in the crystallization reaction system is 0.05 m 2 or less per 100 g; and A step of forming allulose crystals while maintaining the supersaturation of the allulose solution at 1.15 or less.

15. The preparation method according to claim 14, wherein the step of forming the allulose crystals is carried out by cooling the temperature of the allulose solution at a rate of -0.5°C / hr or less.

16. The preparation method according to claim 14, wherein Control the cooling rate of the allulose solution to maintain the supersaturation of the allulose solution at 1.15 or less.

17. The preparation method according to claim 16, wherein, Controlling the cooling rate of the allulose solution includes temporarily stopping the cooling of the allulose solution.

18. The preparation method according to claim 16, wherein, Controlling the cooling rate of the allulose solution is to temporarily stop cooling the allulose solution at a temperature within the range of 15 - 45°C to keep the temperature of the allulose solution constant.

19. The preparation method according to claim 14, wherein the step of forming the psicose crystals comprises temporarily stopping cooling when the supersaturation of the psicose solution exceeds 1.15 until the supersaturation of the psicose solution reaches 1.1 or less to keep the temperature of the psicose solution constant.

20. The preparation method according to claim 14, wherein the step of forming the psicose crystals is carried out by starting to cool the psicose solution when the supersaturation of the psicose solution is greater than 1 to less than 1.

15.

21. The preparation method according to claim 14, wherein the step of forming the psicose crystals is carried out by starting to cool the psicose solution at a temperature of the psicose solution of 25 - 50 °C.

22. The preparation method according to claim 14, wherein the step of forming the psicose crystals is carried out by terminating the cooling of the psicose solution at a temperature of the psicose solution of 15 - 25 °C.

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