Allulose crystals

Abstract

The present application relates to allulose crystals, which have an X-ray powder diffraction pattern including peaks at 2θ diffraction angles of 18.8±0.5°, 15.2±0.5°, and 19.5±0.5° in X-ray powder diffraction (XRD) analysis, a sweetener composition containing allulose crystals, and a method for producing allulose crystals.

Description

[Technical Field]

[0001] The present application relates to allulose crystals. [Background technology]

[0002] Allulose can be used as a functional sweetener to replace sugar or fructose, but because of its low crystallinity, it is difficult to prepare allulose in a uniformly crystalline form. Even when prepared in a crystalline form, it suffers from the problem of caking due to sudden changes in temperature and humidity during storage. In particular, when allulose crystals are packaged in paper bags, the surface caking phenomenon, in which the crystal particles clump together due to moisture and pressure in the atmosphere, can be accelerated. Once surface caking begins, the caking hardness increases further over long-term storage. This high caking hardness significantly limits the use of the product.

[0003] Therefore, there is a need for a novel allulose crystal that is inhibited from solidifying during long-term storage, has low hygroscopicity, is excellent in fluidity, and has improved usability. Summary of the Invention [Problem to be solved by the invention]

[0004] An example of the present application is to provide allulose crystals having a specific diffraction angle pattern.

[0005] Another example of the present application is to provide a sweetener composition comprising allulose crystals having a specific diffraction angle pattern.

[0006] Another example of the present application is to provide a method for producing allulose crystals having a specific diffraction angle pattern, which includes the steps of: adjusting the total specific surface area of ​​all seed crystals contained in a crystallization reaction system and adding the seed crystals to an allulose solution; and adjusting the degree of supersaturation of the allulose solution to produce allulose crystals. [Means for solving the problem]

[0007] An example of the present application relates to allulose crystals having an X-ray powder diffraction pattern containing characteristic peaks at 2θ diffraction angles of 18.8±0.5°, 15.2±0.5°, and 19.5±0.5° in X-ray powder diffraction (XRD) analysis.

[0008] Yet another example of the present application relates to a sweetener composition comprising allulose crystals according to an example of the present application.

[0009] In another example of the present application, the total specific surface area of ​​all seed crystals contained in the crystallization reaction system is 0.05 m 2 and a step of producing allulose crystals by maintaining the degree of supersaturation of the allulose solution at 1.15 or less. [Effects of the Invention]

[0010] The allulose crystals according to one example of the present application have a different X-ray spectrum composition, and the specific surface area of ​​the final product is 0.04 m 2 The crystals have a particle size of 230 μm or more, with a relatively uniform crystal morphology and improved transparency, and have improved moisture absorption and fluidity, increasing convenience in use and reducing surface hardening during storage, improving stability during product packaging, storage, transportation, and distribution, as well as usability during long-term storage.In addition, the crystals themselves reduce the bitterness and unpleasant taste felt after the existing sweetness, and can achieve a texture similar to that of sugar. [Brief explanation of the drawings]

[0011] [Figure 1a] FIG. 1 shows the appearance of allulose crystals produced without adjusting the degree of supersaturation and cooling rate of the allulose solution. [Figure 1b] FIG. 1 shows the appearance of allulose crystals according to an example of the present application. [Figure 2] 1 is a graph showing the moisture absorption rate of allulose crystals according to an example of the present application. [Figure 3]1 is a graph showing the rate of change in solidification hardness of allulose crystals according to an example of the present application. [Figure 4] 1 is a sweetness profile graph of the sensory evaluation results of allulose crystals according to an example of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present application is described in more detail below. The allulose crystals according to one example of the present application may have an X-ray powder diffraction pattern including peaks at 2θ diffraction angles of 18.8±0.5°, 15.2±0.5°, and 19.5±0.5° in X-ray powder diffraction (XRD) analysis. Specifically, the allulose crystals may have an X-ray powder diffraction pattern including peaks at 2θ diffraction angles of 18.8±0.2°, 15.2±0.2°, and 19.5±0.2° in X-ray powder diffraction (XRD) analysis.

[0013] As an example, the allulose crystals may have an X-ray powder diffraction pattern in XRD analysis 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°.

[0014] As an example, the allulose crystals may have an X-ray powder diffraction pattern in XRD analysis 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°.

[0015] The peak may have 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 an X-ray powder diffraction (XRD) analysis. The relative intensity of the peaks is expressed as a relative numerical percentage of the intensity of each peak, with the intensity of the peak with the greatest intensity being 100%.

[0016] Among the peaks, several peaks in descending order of relative intensity, or peaks with a relative intensity equal to or greater than a certain value, may be major peaks that determine the crystalline form. For example, the major peaks may be 1 to 5, 1 to 4, 1 to 3, or 1 to 2 peaks with the highest relative intensities. For example, the major peaks may be peaks with a relative intensity of 50% or more, 55% or more, or 60% or more.

[0017] Therefore, the diffraction angle of the allulose crystals may be the diffraction angle of a major peak having a high relative intensity in X-ray powder diffraction (XRD) analysis, and the diffraction angles may be listed in order starting from the diffraction angle having the highest relative intensity in X-ray powder diffraction (XRD) analysis.

[0018] For example, the allulose crystals may have an X-ray powder diffraction pattern including characteristic peaks at 2θ diffraction angles of 18.8±0.5°, 15.2±0.5°, and 19.5±0.5° in order of relative intensity from highest to lowest in X-ray powder diffraction (XRD) analysis. Specifically, the allulose crystals may have an X-ray powder diffraction pattern including characteristic peaks at 2θ diffraction angles of 18.8±0.2°, 15.2±0.2°, and 19.5±0.2° in order of relative intensity from highest to lowest in X-ray powder diffraction (XRD) analysis.

[0019] For example, the allulose crystals may have an X-ray powder diffraction pattern including characteristic peaks at 2θ diffraction angles of 18.8±0.5°, 15.2±0.5°, 19.5±0.5°, and 28.4±0.5° in order of relative intensity in X-ray powder diffraction (XRD) analysis. Specifically, the allulose crystals may have an X-ray powder diffraction pattern including characteristic peaks at 2θ diffraction angles of 18.8±0.2°, 15.2±0.2°, 19.5±0.2°, and 28.4±0.2° in order of relative intensity in X-ray powder diffraction (XRD) analysis.

[0020] For example, the allulose crystals may have an X-ray powder diffraction pattern including characteristic peaks at 2θ diffraction angles of 18.8±0.5°, 15.2±0.5°, 19.5±0.5°, and 20.3±0.5° in order of relative intensity in X-ray powder diffraction (XRD) analysis. Specifically, the allulose crystals may have an X-ray powder diffraction pattern including characteristic peaks at 2θ diffraction angles of 18.8±0.2°, 15.2±0.2°, 19.5±0.2°, and 20.3±0.2° in order of relative intensity in X-ray powder diffraction (XRD) analysis.

[0021] As an example, the allulose crystals may have an X-ray powder diffraction pattern in which the peak with the highest relative intensity in X-ray powder diffraction (XRD) analysis is located at a 2θ diffraction angle of 18.8±0.5° or 18.8±0.2°.

[0022] The allulose crystals according to one embodiment of the present application have a low specific surface area and a high tap density, which reduces interparticle friction, making particles more mobile, and further reducing the volume during tapping, making them advantageous for storage and distribution.

[0023] The allulose crystal according to one embodiment of the present application has a low surface solidification hardness increase rate and a low moisture absorption rate, and is therefore highly stable during storage. In the case of a packaged product, where the packaging material is in contact with the product, sudden changes in temperature and humidity can cause surface solidification depending on the storage conditions. In particular, in the case of paper bag packaging, solidification can be accelerated, and once surface solidification begins, the solidification hardness can be further strengthened during long-term storage. In an embodiment of the present application, the allulose crystal according to one embodiment of the present application was measured for solidification hardness and moisture absorption rate increase rate by simulating normal storage conditions or long-term exposure to the effects of external air. The results showed that the allulose crystal had a lower solidification hardness and moisture absorption rate than conventional allulose crystals.

[0024] In addition, the allulose crystals according to one embodiment of the present application have a high average particle size and a low angle of repose, and have good fluidity without accumulation or stagnation of crystal particles, making them easy to transport through piping during the manufacturing process and reducing losses in the dehydration / drying / cooling process lines. Furthermore, the production speed in the packaging process is improved and the frequency of packaging defects is reduced, thereby improving productivity and yield in overall product production.

[0025] The angle of repose of allulose crystals can change depending on the diffraction angle and relative intensity of the peaks in the XRD analysis results, and can be affected by this. For example, even if peaks are at the same 2θ diffraction angle in X-ray powder diffraction (XRD) analysis, when the relative intensity of the peaks is taken into consideration, differences in the orientation or morphology of the crystals can result in differences in the angle of repose.

[0026] The allulose crystals according to the present invention may have a low angle of repose, for example, the angle of repose of the allulose crystals may be 48° or less, 47° or less, 46° or less, 45° or less, 44° or less, 43° or less, or 42.5° or less, specifically 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°. Furthermore, the angle of repose of the allulose crystals may be 120% or less, 115% or less, 110% or less, 108% or less, 107% or less, or 106% or less, based on the angle of repose of sugar (100%), and may be at a level similar to that of sugar. In this case, the lower limit of the angle of repose of the allulose crystals based on the angle of repose of sugar (100%) may be, for example, 95% or more, 96% or more, 97% or more, 98% or more, 99% or more, 100% or more, more 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 deposition angle and high fluidity. Therefore, the allulose crystals according to one embodiment of the present application have a uniform particle shape and excellent fluidity.

[0027] Specifically, the allulose crystal according to one example of the present application may have one or more properties selected from the group consisting of the following (1) to (5):

[0028] (1) Specific surface area is 0.04m 2 / g or less, 0.035m 2 / g or less, 0.03m 2 / g or less, or 0.025m 2 / g or less, (2) a volume average particle size (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; (3) Angle of repose is 48° or less, 47° or less, 46° or less, 45° or less, 44° or less, 43° or less, or 42.5° or less; (4) When stored for 15 hours at a temperature of 25°C and a relative humidity of 70%, the moisture absorption rate is 24% or less, 23% or less, 22% or less, or 21.5% or less; and (5) After storing the product under conditions of a temperature of 40°C and a relative humidity of 70% for 0.5 hours and then leaving it at a temperature of 25°C for 30 minutes, the hardness increase rate after applying a pressure of the same weight as the allulose crystals for 30 minutes is 40% or less, 35% or less, 30% or less, 25% or less, or 20% or less.

[0029] The allulose crystals according to one example of the present application have a specific surface area of ​​0.05 m2 in total for all seeds contained in the crystallization reaction system. 2 / 100g or less, 0.045m 2 / 100g or less, 0.04m 2 / 100g or less, 0.035m 2 / 100g or less, or 0.03m 2 It may be crystallized under conditions where the total amount of the cellulose is 100g or less.

[0030] The total specific surface area of ​​all the seed crystals present in the crystallization reaction system is the average specific surface area value of the seed crystal particles (m 2The total specific surface area of ​​all the seeds is calculated by the product of the specific surface area (g / 100g) and the amount of seed crystals added (g / 100g). The total specific surface area of ​​all the seeds can be set by adjusting one or more of the average specific surface area of ​​the seed crystal particles and the amount of seed crystals added. According to the embodiment of the present application, due to the difference in particle size of the seed crystals added during the production of allulose crystals, the average particle size of allulose crystals is stably large depending on the total specific surface area of ​​all the seed crystals in the crystallization reaction system, and it has been confirmed that allulose crystals having a specific diffraction angle pattern are produced due to differences in the deposition and morphology of the particles formed during the crystallization process, and the configuration of the main peaks of the X-ray diffraction angle is different from that of conventional allulose crystals.

[0031] The allulose crystals according to one example of the present application may be crystallized under conditions in which the degree of supersaturation of the allulose solution is 1.15 or less, specifically greater than 1 and less than 1.15, or greater than 1.01 and less than 1.15. According to an embodiment of the present application, when the degree of supersaturation of the allulose solution exceeds 1.15 during production of allulose crystals, the X-ray powder diffraction patterns of the produced allulose crystals are different from those produced when the degree of supersaturation is maintained at 1.15 or less. Thus, the allulose crystals according to one example of the present application may be crystallized under conditions in which the degree of supersaturation of the allulose solution is 1.15 or less, and may have an X-ray powder diffraction pattern including peaks at 2θ diffraction angles of 18.8±0.5°, 15.2±0.5°, and 19.5±0.5° in X-ray powder diffraction (XRD) analysis.

[0032] In another example of the present application, the total specific surface area of ​​all seed crystals contained in the crystallization reaction system is 0.05 m 2 and a step of producing allulose crystals by maintaining the degree of supersaturation of the allulose solution at 1.15 or less.

[0033] The allulose solution for producing allulose crystals may be a high-purity allulose solution with a high allulose content, and may have an allulose content of 80 wt% or more, 85 wt% or more, 90 wt% or more, 91 wt% or more, 92 wt% or more, 93 wt% or more, 94 wt% or more, or 95 wt% or more based on a solid content of 100 wt%. The allulose solution may also be concentrated for crystallization to have a solid content of 80 wt% or more, 85 wt% or more, or 85% or more.

[0034] In the step of producing allulose crystals, the temperature of the allulose solution may be cooled at a rate of -0.5°C / hr or less, -0.4°C / hr or less, or -0.3°C / hr or less. In this case, in the step of producing allulose crystals, the cooling rate may be adjusted to control the degree of supersaturation of the allulose solution, and for example, the step of adjusting the cooling rate of the allulose solution may be included at least once to maintain the degree of supersaturation of the allulose solution at 1.15 or less.

[0035] In order to maintain the degree of supersaturation of the allulose solution at 1.15 or less, the cooling rate or allulose solids content of the allulose solution may be adjusted. The adjustment of the cooling rate may specifically include a cooling rate deceleration section, for example, adjusting the cooling rate to 0°C / hr, i.e., interrupting cooling. The interruption of cooling may be interrupted until the degree of supersaturation of the allulose solution is 1.15 or less. Therefore, the adjustment of the cooling rate of the allulose solution may be temporarily interrupted. Specifically, the adjustment may be temporarily interrupted to maintain a constant temperature of the allulose solution.

[0036] Therefore, in one example of the present application, the process of producing allulose crystals by maintaining the supersaturation of the allulose solution at 1.15 or less, or adjusting the cooling rate of the allulose solution so that the supersaturation of the allulose solution is maintained at 1.15 or less, may include a first cooling section, a cooling rate deceleration section, and a second cooling section, and the cooling rate deceleration section may be included at least once and may be performed until the supersaturation of the allulose solution reaches 1.15 or less. Specifically, the first cooling section may involve cooling the allulose solution at a constant rate, and then reducing the cooling rate in the cooling rate deceleration section, and performing the second cooling section when the supersaturation of the allulose solution reaches 1.15 or less. The cooling rates in the first cooling section and the second cooling section may be the same or different.

[0037] For example, the cooling rate of the allulose solution may be adjusted by temporarily interrupting cooling within the range of 15 to 45°C, 15 to 40°C, 15 to 39°C, 15 to 38°C, 20 to 45°C, 20 to 40°C, 20 to 39°C, 20 to 38°C, 25 to 45°C, 25 to 40°C, 25 to 39°C, 25 to 38°C, 30 to 45°C, 30 to 40°C, 30 to 39°C, 30 to 38°C, 35 to 45°C, 35 to 40°C, 35 to 39°C, 35 to 38°C, 36 to 45°C, 36 to 40°C, 36 to 39°C, 36 to 38°C, 37 to 45°C, 37 to 40°C, 37 to 39°C, or 37 to 38°C. In this case, the temperature of the allulose solution is maintained constant within the range.

[0038] Specifically, the process of producing allulose crystals may include, when the degree of supersaturation of the allulose solution exceeds 1.15, stopping the cooling and maintaining the temperature of the allulose solution constant until the degree of supersaturation of the allulose solution reaches 1.1 or less.

[0039] The step of producing allulose crystals may involve starting to cool the allulose solution when the degree of supersaturation of the allulose solution is greater than 1 and not greater than 1.15, or in the range of 1.01 to 1.15.

[0040] The step of producing allulose crystals may involve starting cooling of the allulose solution at a temperature of 25 to 50°C, 30 to 50°C, 35 to 50°C, 40 to 50°C, 25 to 45°C, 30 to 45°C, 35 to 45°C, or 40 to 45°C.

[0041] The step of producing allulose crystals may comprise completing the cooling of the allulose solution at a temperature of 15 to 25°C, 15 to 23°C, 15 to 20°C, 18 to 25°C, 18 to 23°C, or 18 to 20°C. [Example]

[0042] The present application will be described in more detail below with reference to the following examples, but these examples are for illustrative purposes only and do not limit the scope of the present application.

[0043] Comparative Example 1. Allulose Crystal Production (1) High-performance liquid chromatography (HPLC) analysis for allulose content was performed using an RI detector with a Biorad carbohydrate Aminex-HPX 87C column set at 80°C, and the mobile phase was distilled water (DW) at 0.6 ml / min.

[0044] A high-purity allulose solution with a purity of 95 wt% was concentrated to a solids concentration of 87.2%. The allulose solution was cooled from 35°C to 10°C at a rate of -1°C / hr to produce allulose crystals. The initial crystallization solution had a supersaturation of approximately 1.5, and no allulose seeds were added. The mother liquor was removed by centrifugal dehydration, and the allulose crystals were washed with cooled water and then dried to recover the allulose crystals. The mean particle size of the primary allulose crystals was 225 μm.

[0045] The obtained allulose crystals were pulverized using a Hammer mill for use 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.

[0046] [Table 1]

[0047] Comparative Example 2. Allulose crystal production (2) The high-purity allulose solution separated at a purity of 95% by weight was concentrated to a solid content of 85%. The temperature of the solution in the crystallization reactor was maintained at 50°C, and the crystallization was carried out to obtain a crystal with an average particle size of 98.0 μm and an average specific surface area of ​​0.196 m. 2 1 / g of seed crystals were mixed with ethanol and added at a concentration of 0.3% and uniformly distributed. At this time, the supersaturation of the initial crystallization solution was 1.39, and the cooling temperature was cooled to 30°C at a rate of -1°C / hr for crystallization. The mother liquor was removed by centrifugal dehydration, and the crystals were washed with cooled water and dried to recover the allulose crystals.

[0048] The physical properties of the produced allulose crystals are shown in Table 1. The particle size of the allulose crystals of Comparative Example 2 was an average particle size of 154.04 μm and an average specific surface area of ​​0.0558 m 2 / g.

[0049] Comparative Example 3. Allulose Crystal Production (3) A high-purity allulose solution with a purity of 95 wt% was concentrated to a solid content of 86.1%, and the temperature of the concentrated allulose solution was adjusted to 44.5°C to adjust the supersaturation of the allulose solution to 1.05. The crushed crystals prepared in Comparative Example 1 were added to the allulose solution as seeds at a concentration of 1.7 wt%, and stirred to distribute evenly, and then the crystallization process was prepared. At this time, the total specific surface area of ​​the added seeds was 0.327 m 2 / g × 1.7g / 100g ≒ 0.556m2 / 100g.

[0050] Thereafter, allulose crystals were produced by constantly cooling the temperature of the allulose solution at a rate of -0.3°C / hr. In order to maintain a constant degree of supersaturation of the allulose solution, the cooling rate was not adjusted and the solution was cooled at a constant rate until the final temperature reached 20°C. During the crystallization process, the degree of supersaturation increased to 1.19. The mother liquor was removed by centrifugal dehydration, and the crystals were washed with cooled water and then dried to recover the allulose crystals.

[0051] The physical properties of the produced allulose crystals are shown in Table 1. Comparative Example 3 The average particle size of the allulose crystals was 165.6 μm, and the specific surface area was 0.0513 m 2 The appearance of the produced allulose crystals is shown in Figure 1a.

[0052] Comparative Example 4. Allulose crystal production (4) A high-purity allulose solution with a purity of 95% by weight was concentrated to a solid content of 86.3%, and the temperature of the concentrated allulose solution was adjusted to 45°C to adjust the degree of supersaturation of the allulose solution to 1.057. The allulose solution was added with an average particle size of 189.5 μm and an average specific surface area of ​​0.040 m 2 99% pure allulose crystals (1.0g / g) were added as seeds at a concentration of 2.0 wt% and stirred to distribute evenly, and then the crystallization process was prepared. The total specific surface area of ​​the seeds was 0.040 m 2 / g × 2.0g / 100g ≒ 0.080m 2 / 100g.

[0053] Thereafter, allulose crystals were produced by constantly cooling the temperature of the allulose solution at a rate of -0.3°C / hr. In order to maintain a constant degree of supersaturation of the allulose solution, the cooling rate was not adjusted and the solution was cooled at a constant rate until the final temperature reached 20°C. During the crystallization process, the degree of supersaturation increased to 1.213. The mother liquor was removed by centrifugal dehydration, and the crystals were washed with cooled water and then dried to recover the allulose crystals.

[0054] The physical properties of the produced allulose crystals are shown in Table 1. Comparative Example 4 The average particle size of the allulose crystals was 227.8 μm and the specific surface area was 0.0410 m 2 / g.

[0055] Example 1. Production of allulose crystals (5) A high-purity allulose solution with a purity of 95% by weight was concentrated to a solid content of 85.4%, and the temperature of the concentrated allulose solution was adjusted to 44.2°C to adjust the degree of supersaturation of the allulose solution to 1.011. The allulose solution was added with the same average particle size of 189.5 μm and average specific surface area of ​​0.040 m as in Comparative Example 4. 2 99% pure allulose crystals (1.0 wt. % / g) were added as seeds and stirred to distribute evenly, and then the crystallization process was prepared. The total specific surface area of ​​the seeds was 0.040 m 2 / g × 1.0g / 100g ≒ 0.04m 2 / 100g.

[0056] The allulose solution was then cooled at a constant rate of -0.3°C / hr to produce allulose crystals. To maintain the supersaturation of the allulose solution at 1.15 or less, the supernatant was collected from the allulose solution and its concentration was measured. Cooling was stopped at approximately 38°C, where the supersaturation reached 1.145. The temperature was maintained until the supersaturation reached 1.1 or less, and cooling was resumed once the supersaturation value of the supernatant had decreased to 1.082. The allulose solution was then cooled to 20°C, where the supersaturation only increased to 1.131. The crystallization reaction was terminated when the supersaturation no longer increased. The mother liquor was removed by centrifugation, and the crystals were washed with cooled water and then dried to recover the allulose crystals.

[0057] The physical properties of the produced allulose crystals are shown in Table 1. The average particle size of the allulose crystals in Example 1 was 282.7 μm, and the specific surface area was 0.0298 m 2 / g. A relatively uniform particle distribution was observed, and the specific surface area was lower than that of Comparative Example 4.

[0058] Example 2. Production of allulose crystals (6) A high-purity allulose solution with a purity of 95 wt% was concentrated to a solid content of 85.6%, and the temperature of the concentrated allulose solution was adjusted to 44.7°C to adjust the supersaturation of the allulose solution to 1.01. The crystals produced in Comparative Example 2 were added to the allulose solution as seeds at a concentration of 0.5 wt%, and the solution was stirred to distribute them evenly, preparing for the crystallization process. The total specific surface area of ​​the added seeds was 0.0558 m 2 / g×0.5g / 100g=0.0279m 2 / 100g.

[0059] The temperature of the allulose solution was then cooled at a constant rate of -0.3°C / hr to produce allulose crystals. To maintain the supersaturation of the allulose solution below 1.15, the supernatant was collected from the allulose solution and its concentration was measured. Cooling was stopped at approximately 38°C, where the supersaturation reached 1.145. The temperature was maintained until the supersaturation reached 1.1 or less, and cooling was resumed when the supersaturation value of the supernatant reached 1.091. When the temperature of the allulose solution was lowered below 25°C, a section in which the supersaturation gradually rose to 1.144 was observed. The temperature was maintained at 20°C without terminating the crystallization. After the supersaturation was reduced to 1.110, the crystallization reaction was terminated. The mother liquor was removed by centrifugation, and the crystals were washed with cooled water and dried to recover the allulose crystals.

[0060] The physical properties of the produced allulose crystals are shown in Table 1. The allulose crystals of Example 2 grew very large with an average particle size of 378.4 μm, and the specific surface area was 0.0203 m 2 The appearance of the produced allulose crystals is shown in Figure 1b.

[0061] Test Example 1: Confirmation of the crystalline form of allulose The allulose crystals obtained in Comparative Examples 1 and 2 and Examples 1 and 2 were subjected to X-ray diffraction analysis under the following analytical conditions, and the main peaks in the X-ray diffraction patterns of the allulose crystals are listed in Table 2 in order of relative intensity (Relative Intensity%).

[0062] Analytical equipment: D / MAX-2200 Ultima / PC Manufacturer: Rigaku International Corporation (Japan) X-ray sauce system target: sealed tube Cu Tube voltage: 45kV / Tube current: 200mA Scan range: 5~80°2θ Step size: 0.01° Scan speed: 5° / min

[0063] [Table 2]

[0064] As shown in Table 2, the allulose crystals according to one example of the present application had a specific diffraction angle pattern different from that of conventional allulose crystals.

[0065] Specifically, the diffraction angles (2θ) of the main peaks in the X-ray diffraction pattern of the allulose crystals obtained in Comparative Example 1 were 15.35°, 18.83°, 30.95°, and 47.15° in order of relative intensity. The main XRD diffraction angle peaks of the allulose crystals obtained primarily in Comparative Example 1 and the crushed crystals were the same, which means that the crystal particles formed during the crystallization process maintain the same crystal shape even if their external shape is deformed through crushing, etc.

[0066] In addition, the diffraction angles (2θ) of the main peaks in the X-ray diffraction pattern of the allulose crystals of Comparative Example 2 were shown to be 15.2°, 18.8°, 30.8°, and 29.7° in order of relative intensity. In addition, the diffraction angles (2θ) of the main peaks in the X-ray diffraction pattern of the allulose crystals of Comparative Example 3 were shown to be 15.2°, 18.8°, 30.8°, and 28.3° in order of relative intensity. In addition, the diffraction angles (2θ) of the main peaks in the X-ray diffraction pattern of the allulose crystals of Comparative Example 4 were shown to be 15.2°, 18.8°, 30.8°, and 19.5° in order of relative intensity.

[0067] On the other hand, in the X-ray diffraction pattern of the allulose crystals according to Example 1 of the present application, the diffraction angles (2θ) of the major peaks were shown to be 18.8°, 15.2°, 19.5°, and 28.4°, and there was a difference in the relative intensity of the major peaks compared to the X-ray diffraction pattern of the allulose crystals prepared conventionally.

[0068] In addition, the X-ray diffraction pattern of the allulose crystals according to Example 2 of the present application showed that the diffraction angles (2θ) of the major peaks were 18.8°, 15.2°, 19.5°, and 20.3°. When compared with the X-ray diffraction pattern of allulose prepared conventionally as in Example 1, there were differences in the intensity values ​​of the major peaks. In the results of X-ray diffraction analysis of allulose crystals, the diffraction angles (2θ) of the peaks and the order of the relative intensities of the diffraction angles of the peaks affect the orientation and angle of repose of the crystals, so the morphology, structure, and orientation of allulose crystals may differ.

[0069] Test Example 2. Analysis of the appearance characteristics of the produced allulose crystals Using a color difference meter (Spectro color meter SA-2000, Nippon Denshoku Industries Co., Ltd.) and a whiteness tester (Whiteness Tester C-130, KETT electric laboratory), the lightness (L value), redness (a value), yellowness (b value), and whiteness of the allulose crystals produced in Comparative Examples 3 and 4 and Examples 1 and 2 were measured and are shown in Table 3.

[0070] [Table 3]

[0071] The whiter the grain, the higher the whiteness value. Sugar generally exhibits a whiteness level of 80-86. When a large amount of fine powder is present or the particle surface is dull, or in the case of rice, the starch particles are not densely packed and the rice grains are loosely formed due to the cultivation environment, resulting in milky white grains, the whiteness value may be even higher due to differences in light scattering. The crystals of Examples 1 and 2 exhibited a similar level of whiteness to sugar compared to Comparative Examples 3 and 4, and showed differences in color value, such as a lower yellowness (b value) measured in color difference analysis. A high yellowness indicates that the crystal mother liquor may adhere to the crystal particles during the dehydration and washing process after crystallization. Even a very small amount of crystal mother liquor remaining on the particles may induce browning or promote solidification during long-term storage. The allulose crystals according to one example of the present application exhibited a low yellowness, which means that the crystal particles were uniformly formed and smoothly washed during the dehydration process.

[0072] Test Example 3. Analysis of particle characteristics of allulose crystals The allulose crystals obtained in Comparative Examples 1 to 4 and Examples 1 and 2 were measured for average particle size and particle size distribution using a laser diffraction particle size analyzer, and the measured specific surface areas are shown in Table 1.

[0073] -Particle size analysis equipment: Laser Diffraction particle analyzer, Mastersizer 2000 (MALVERN Panalytical Ltd.) -Dispersion Unit: Hydro 2000 MU(wet type) -Dispersion solvent: Isopropyl alcohol

[0074] As shown in Table 1, the allulose crystals according to one example of the present application have a large average particle size of 230 μm or more, and a particle size of 0.04 μm or more. 2 / g or less.

[0075] Test Example 4. Measurement of fluidity of allulose crystals 150 g of each of the allulose crystal samples obtained in Comparative Examples 3 and 4 and Examples 1 and 2 was prepared, and the angle of repose was measured using an automatic stirring type repose angle measuring device (manufacturer: K-one Nano., Ltd., model name: BT-200DA). The allulose crystal powder sample was passed at a constant size through a special funnel fixed at a constant height above a perfectly flat reference plate of the measuring device, and the angle of repose of the cone-shaped sample deposited on the reference plate was measured, and the results are shown in Table 4. The angles of repose were also converted to relative angles of repose based on a sugar angle of repose of 100%, and the values ​​are shown in Table 4.

[0076] [Table 4]

[0077] As shown in Table 4, the allulose crystals according to one example of the present application have improved particle fluidity compared to conventional allulose crystals and have an angle of repose similar to that of sugar, which has been confirmed to increase the convenience of use when adding crystalline products or transporting them on a line.

[0078] Test Example 5. Comparison of hygroscopicity of allulose crystals 10 g of each of the allulose crystal samples prepared in Comparative Examples 1 to 3 and Example 2 was accurately weighed and evenly spread on a weighing dish. The samples were stored in a thermo-hygrostat at 25°C and 70% relative humidity, and the weight of the samples was measured over time. The weight increase due to moisture absorption relative to the initial weight was calculated and shown as a percentage in Table 5 and Figure 2.

[0079] [Table 5]

[0080] As shown in Table 5 and FIG. 2, the allulose crystals according to one example of the present application have improved hygroscopicity and can maintain stability during product packaging and distribution.

[0081] Test Example 6: Measurement of solidified hardness of allulose crystals 25 g of allulose crystal samples prepared in Comparative Examples 1 to 3 and Example 2 were placed in identical aluminum dishes with the surface evenly balanced without applying external pressure. They were stored under constant temperature and humidity conditions of 40°C and 70% relative humidity. At 0 hours and 30 minutes of storage, each sample was removed and left at room temperature (25°C) for 30 minutes to cool. A weight of the same weight as the sample (25 g) was then placed on the sample surface for 30 minutes to induce solidification of the allulose crystal surface. Specifically, a weight of the same weight as the allulose crystal sample was used to apply pressure to the surface, and allulose crystals were stacked on top to simulate the solidification phenomenon that may occur during storage. The solidification hardness measurement conditions were as follows: -Equipment name: Texture analyzer TAXTplus (stable micro systems) -Cylinder probe: 25mmφ Perspex -Test speed: 2mm / sec -Trigger force: 5g The solidification hardness of each sample over time is shown in Table 6 and Figure 3.

[0082] [Table 6]

[0083] As shown in Table 6 and Figure 3, the allulose crystals of Example 2 had the lowest surface solidification hardness and showed the smallest change in surface solidification hardness even with increasing exposure time to high-temperature, hygroscopic conditions. In contrast, the allulose crystals of Comparative Examples 1 to 3, which had differences in particle size and specific surface area, showed not only a high initial solidification hardness but also a large increase in solidification hardness. Therefore, the impact of the external environment during long-term storage is significant, and the greater the storage load, the more accelerated the surface solidification of the product. It was confirmed that the allulose crystal sample according to one example of the present application exhibited improved storage stability by mitigating the degree of surface solidification even under harsh storage conditions. Therefore, this can provide significant industrial support for improving the storage stability of products during packaging, storage, transportation, and distribution.

[0084] Test Example 7. Sensory evaluation of allulose crystals For the sensory evaluation, identical amounts of allulose crystal samples prepared in Comparative Examples 1 to 3 and Example 2 were prepared, and 15 panelists with a high level of understanding of sensory testing and over 10 years of sensory testing experience were selected. The samples were individually provided to the sensory testers and rated using a 5-point scale. For sweetness and refreshing sensation, a higher score indicated a "good" or "strong" sweetness or refreshing sensation, and for bitterness and off-flavor / off-flavor, a lower score indicated a weaker bitterness or off-flavor and "good," and a higher score indicated a stronger bitterness or off-flavor and "poor."

[0085] Each sample was labeled with a three-digit number randomly selected using a random number table, and the order in which samples were presented was always determined randomly. Testers were also provided with lukewarm water to rinse their mouths with. The sensory testing room was maintained at a constant temperature (25±1°C) and free of odors.

[0086] The content and method of evaluation were sweetness, refreshing feeling, bitterness, and off-flavor / off-flavor items as the sensory characteristics of allulose crystals. By providing sugar as a control sample, standard values ​​for each sensory item were presented, and the sensory items were compared with sugar and evaluated using a 15cm linear scale. The sensory evaluation results are shown in Table 7 below, and the sweetness profile graph of the sensory evaluation results is shown in Figure 4.

[0087] [Table 7]

[0088] As a result of the sensory evaluation, the sweetness was analyzed to be lower than that of sugar, consistent with known sweetness levels, but the sweetness profile of Example 2 compared to the comparative sample was similar to that of sugar, and in particular, the comparative sample, which had a large surface area of ​​allulose crystal particles, exhibited a stronger sensory perceived intensity and was inferior to sugar in terms of bitterness and off-flavor characteristics.In contrast, the allulose crystals according to one example of the present application had a small specific surface area and a texture very similar to that of sugar, and were found to have the least perceived off-flavor intensity and improved bitterness.

Claims

1. An allulose crystal having an X-ray powder diffraction pattern including peaks at 2θ diffraction angles 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 of claim 1, having an X-ray powder diffraction pattern including peaks at 2θ diffraction angles 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 of claim 1, having an X-ray powder diffraction pattern including peaks at 2θ diffraction angles 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 has a relative intensity of 5% or more.

5. The specific surface area of ​​the allulose crystal is 0.04 m 2 The allulose crystal according to claim 1, wherein the crystalline allulose has a molecular weight of 1 / 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 allulose crystal according to claim 1, wherein the allulose crystal has an angle of repose that is 120% or less compared to the angle of repose of sugar.

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

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

10. The allulose crystals according to claim 1, wherein the allulose crystals are stored at a temperature of 40°C and a relative humidity of 70% for 0.5 hours, left at a temperature of 25°C for 30 minutes, and then subjected to a pressure of the same weight as the allulose crystals for 30 minutes, after which the increase in hardness is 40% or less.

11. The allulose crystals have a total specific surface area of ​​0.05 m2 for all seed crystals contained in the crystallization reaction system. 2 The allulose crystal according to claim 1, which is crystallized under conditions where the total weight of the allulose crystal is 100g or less.

12. The allulose crystal according to claim 1, wherein the allulose crystal is crystallized under conditions in which the degree of supersaturation of the allulose solution is 1.15 or less.

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

14. The total specific surface area of ​​all seed crystals contained in the crystallization reaction system is 0.05 m 2 adding seed crystals to the allulose solution so that the total weight of the allulose solution is 100 g or less; and The step of producing allulose crystals by maintaining the degree of supersaturation of the allulose solution at 1.15 or less, The method for producing allulose crystals according to any one of claims 1 to 12.

15. The method according to claim 14, wherein the step of producing allulose crystals comprises cooling the temperature of the allulose solution at a rate of −0.5° C. / hr or less.

16. The method of claim 14, wherein the cooling rate of the allulose solution is adjusted so that the degree of supersaturation of the allulose solution is maintained at 1.15 or less.

17. The method of claim 16, wherein adjusting the cooling rate of the allulose solution comprises temporarily interrupting the cooling of the allulose solution.

18. The method of claim 16, wherein the cooling rate of the allulose solution is controlled by temporarily stopping the cooling of the allulose solution at a temperature in the range of 15 to 45°C to maintain the temperature of the allulose solution constant.

19. 15. The method of claim 14, wherein the step of producing allulose crystals comprises temporarily suspending cooling until the degree of supersaturation of the allulose solution reaches 1.1 or less when the degree of supersaturation of the allulose solution exceeds 1.15, thereby maintaining the temperature of the allulose solution constant.

20. The method of claim 14, wherein the step of producing allulose crystals comprises starting to cool the allulose solution when the degree of supersaturation of the allulose solution is greater than 1 and less than or equal to 1.

15.

21. The method of claim 14, wherein the step of producing allulose crystals comprises starting to cool the allulose solution at a temperature of 25 to 50°C.

22. The method of claim 14, wherein the step of producing allulose crystals comprises completing the cooling of the allulose solution at a temperature of 15 to 25°C.

Images