Method for producing granule, and granule

Abstract

To provide a method for producing a granule in which functional material is retained and that is excellent in fluidity.SOLUTION: A method for producing granule comprises:a step of obtaining a mixed suspension that contains at least one selected from a group consisting of crystalline sugar and crystalline sugar alcohol and a functional material and in which a part of the sugar and / or sugar alcohol is contained in a crystalline state, and a step of spraying-drying the mixed suspension under a low temperature condition.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for producing granules and the granules.

Background Art

[0002] Enzymes, yeasts, fragrances, etc. are low-stability functional materials that are easily affected by environmental changes such as heat and acid. When using such components in food and pharmaceutical applications, it is important to maintain stability assuming environmental changes such as temperature and humidity. For example, Patent Document 1 describes a method for obtaining a dried and stabilized composition of a bioactive material by mixing a bioactive material such as a protein or an enzyme with other components in an aqueous solvent to form a viscous slurry, instantaneously freezing this slurry in liquid nitrogen, and further drying this under vacuum.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The composition in a dried state as described in Patent Document 1 may be used in a powdery or granular form. When using a powdery material in food and pharmaceuticals, excellent fluidity is required from the viewpoints of preventing caking and preventing clogging in a line.

[0005] One aspect of the present invention aims to provide a method for producing granules having excellent fluidity in which a functional material is retained.

Means for Solving the Problems

[0006] The inventors of the present invention have found that by using a suspension of sugar in which a part of the crystalline sugar and / or sugar alcohol is present in a crystalline state and spray-drying it together with a functional material under low-temperature conditions, the granules containing the functional material have excellent fluidity, and thus completed the present invention.

[0007] In one aspect, the present invention provides a method for producing granules, comprising: obtaining a mixed suspension containing at least one selected from the group consisting of crystalline sugar and crystalline sugar alcohol and a functional material, wherein a part of the sugar and / or sugar alcohol is contained in a crystalline state; and spray-drying the mixed suspension under low-temperature conditions. Preferably, the spray-drying is performed under the condition that the inlet air temperature is 0 to 60°C.

[0008] Another aspect of the present invention provides granules containing at least one selected from the group consisting of crystalline sugar and crystalline sugar alcohol and a functional material, wherein a part of the sugar and / or sugar alcohol is in a crystalline state and the other part is in an amorphous state.

[0009] In the granules, preferably, the amorphous sugar and / or sugar alcohol and the functional material are retained in the gaps formed between the crystalline sugar and / or sugar alcohol.

[0010] In the above-mentioned granules or the method for producing the same, the sugar and sugar alcohol are preferably monosaccharides, disaccharides, trisaccharides and their sugar alcohols. The average particle size of the crystalline sugar and / or sugar alcohol may be 1 to 80 μm. The functional material may be an enzyme, a microorganism or a fragrance.

Effects of the Invention

[0011] According to one aspect of the present invention, it is possible to provide a method for producing granules with excellent fluidity in which a functional material is retained.

Brief Description of the Drawings

[0012]

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Mode for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

[0014] <Method for Producing Granules> One embodiment of the present invention includes a step of obtaining a mixed suspension containing at least one selected from the group consisting of a crystalline sugar and a crystalline sugar alcohol and a functional material, and containing a part of the sugar and / or the sugar alcohol in a crystalline state (mixing step), and a step of spray-drying the mixed suspension under low-temperature conditions (spray-drying step). It is a method for producing granules.

[0015] First, the mixing process will be described. In the mixing process, in one embodiment, it includes a step of crystallizing a solution containing at least one selected from the group consisting of crystalline sugar and crystalline sugar alcohol (crystallization step), and a step of adding a functional material (addition step).

[0016] In the crystallization step, first, a solution (sugar solution) containing crystalline sugar and / or crystalline sugar alcohol is prepared. The solution may contain at least one selected from the group consisting of crystalline sugar and crystalline sugar alcohol and a solvent. The solvent is, for example, an organic solvent such as ethanol, methanol, acetone, isopropanol, or water.

[0017] From the viewpoint of enhancing the operability in the mixing process, the crystalline sugar and crystalline sugar alcohol are preferably monosaccharides, disaccharides, trisaccharides, and their sugar alcohols.

[0018] Examples of monosaccharides include glucose, galactose, mannose, fructose, allose, altrose, etc. Examples of disaccharides include isomaltulose, sucrose, lactulose, lactose, maltose, trehalose, cellobiose, etc. Examples of trisaccharides include nigerotriose, maltotriose, raffinose, etc. Note that isomaltulose is a disaccharide trademarked by Mitsui Sugar Co., Ltd. as "palatinose".

[0019] Examples of sugar alcohols include sorbitol, erythritol, xylitol, maltitol, lactitol, mannitol, α - glucopyranosyl - 1,1 - mannitol, α - glucopyranosyl - 1,6 - sorbitol, etc.

[0020] The above - mentioned crystalline sugar and sugar alcohol may be used alone or in combination of two or more.

[0021] The content of sugar and / or sugar alcohol in the sugar solution is not particularly limited as long as it is a concentration at which crystals are formed in the crystallization process described later. From the viewpoint of efficiently performing crystallization in the crystallization process, the content of crystalline sugar and / or sugar alcohol contained in the sugar solution is preferably 40% by mass or more, more preferably 45% by mass or more, and still more preferably 50% by mass or more based on the total amount of the sugar solution. From the viewpoint of maintaining good operability in the mixing process and the spray drying process, the content of crystalline sugar and / or sugar alcohol is preferably 90% by mass or less, more preferably 80% by mass or less, and still more preferably 70% by mass or less based on the total amount of the sugar solution. The content of sugar and / or sugar alcohol may be a content that results in a concentration equal to or higher than the saturation solubility. That is, the sugar solution may be a supersaturated solution.

[0022] The Brix value (Bx) of the sugar solution is preferably 50 or more, more preferably 55 or more, and still more preferably 65 or more from the viewpoint of efficiently performing crystallization in the crystallization process, and is preferably 85 or less, more preferably 80 or less, and still more preferably 75 or less from the viewpoint of maintaining good operability in the mixing process and the spray drying process. The Brix value (Bx) in this specification means the refractive Brix value calculated from the refractive index of the sugar solution and can be measured with a Brix meter (for example, a digital refractometer (RX-5000), manufactured by Atago Co., Ltd.).

[0023] When preparing the sugar solution, the solvent may be heated and then crystalline sugar and / or sugar alcohol may be added and dissolved. In this case, the temperature of the solvent is not particularly limited, but is, for example, 70°C or higher. The temperature of the solvent may be 100°C or lower.

[0024] The sugar solution may contain components other than crystalline sugar and / or sugar alcohol. For example, the sugar solution may contain non-crystalline sugar and non-crystalline sugar alcohol. Preferably, the sugar solution contains only crystalline sugar and / or sugar alcohol.

[0025] In the crystallization process, for example, a part of the crystalline sugar and / or sugar alcohol may be crystallized by cooling the sugar solution (cooling crystallization method), or may be crystallized by the reactive crystallization method. Thereby, a suspension (sugar suspension) containing crystalline sugar and / or sugar alcohol and amorphous sugar and / or sugar alcohol can be obtained. In the present invention, the "crystalline sugar and / or sugar alcohol" means a solid sugar and / or sugar alcohol in which the constituent atoms are composed of a three-dimensionally regular repetition, and the "amorphous sugar and / or sugar alcohol" means a solid or liquid sugar and / or sugar alcohol that does not have such a regular repetition.

[0026] When crystallization is performed by the cooling crystallization method, the temperature of the sugar solution by cooling (cooling temperature) may be set according to the type of crystalline sugar and / or sugar alcohol. For example, it may be 60°C or lower, 50°C or lower, or 45°C or lower. The cooling temperature may be 5°C or higher, 10°C or higher, 15°C or higher, or 20°C or higher.

[0027] In the crystallization process, means for controlling the growth of crystals may be performed to adjust the average particle size of the crystals. The means may be performed by a so-called buildup method. For example, it may be a method of performing crystallization while irradiating with ultrasonic waves. That is, the crystallization process may further include a step of irradiating with ultrasonic waves (ultrasonic irradiation step). The ultrasonic irradiation can be performed, for example, on the obtained sugar suspension by an ultrasonic irradiation device (for example, ULTRA SONIC HOMOGENIZER UH-500 manufactured by SMT Co., Ltd.) in the operation of crystallization by cooling the sugar solution described above. The ultrasonic irradiation conditions (frequency of ultrasonic irradiation, temperature of the sugar suspension, ultrasonic irradiation time) may be appropriately adjusted according to the target average particle size of the crystals. When the ultrasonic irradiation step is performed, the liquid after ultrasonic irradiation can be used as the sugar suspension.

[0028] The crystallization rate by the crystallization process is preferably 10% by mass or more, more preferably 20% by mass or more, still more preferably 30% by mass or more, from the viewpoint of easily obtaining granules with excellent fluidity. The crystallization rate is preferably 80% by mass or less, more preferably 60% by mass or less, still more preferably 40% by mass or less, from the viewpoint of maintaining good operability in the spray drying process. The crystallization rate in this specification is calculated by putting 1 g of the sugar suspension into a 1.5 ml Eppendorf tube, centrifuging at 16,000 rpm for 1 minute with a centrifuge (for example, M150IV manufactured by Sakuma Seisakusho Co., Ltd.), discarding the supernatant, and dividing the remaining amount of the crystals by the mass of the sugar suspension.

[0029] The crystallization rate can be adjusted, for example, by performing operations of physically or chemically adding or removing crystals, such as filter filtration, centrifugation, gravitational sedimentation, dissolution by adding water / warming, adjustment of consumption of crystal components due to chemical reactions, etc. Alternatively, it can also be adjusted by operations of increasing crystals, such as crystallization operations (cooling crystallization, evaporation crystallization, antisolvent crystallization, reaction crystallization, salting out), input and mixing of crystal components, etc.

[0030] The sugar suspension only needs to contain crystal nuclei, and the size of the crystal nuclei is not particularly limited as long as it is equal to or larger than the size that can stably exist in the sugar suspension. The size of the crystal nuclei may be, for example, equal to or larger than the critical crystal nuclei.

[0031] The average particle size of the crystalline sugar and / or sugar alcohol obtained by the crystallization process is preferably 1 μm or more, more preferably 5 μm or more, still more preferably 10 μm or more, particularly preferably 20 μm or more, from the viewpoint of maintaining the fluidity of the granules, and is preferably 80 μm or less, more preferably 70 μm or less, still more preferably 60 μm or less, from the viewpoint of preventing the disintegration of the granules. That is, the average particle size of the crystalline sugar and sugar alcohol may be 1 to 80 μm, or may be 5 to 80 μm. The average particle size of the crystals can be adjusted by adding or removing the solvent or solute, changing the solvent temperature, dissolution time, stirring time, crushing with a stirrer or crusher, fractionation by filtration, etc., and crystallization by hydrolysis of sugar, etc.

[0032] The average particle size in this specification can be measured by a digital microscope. For the measurement, for example, SKM-S31B-PC manufactured by Saito Optical Co., Ltd. can be used. With a digital microscope, for any 10 or more particles or crystallized grains, the major axis lengths of 10 or more crystalline sugars and / or sugar alcohols that constitute them are measured, and the average value of the measured major axis lengths is calculated, which is referred to as the "average particle size".

[0033] In the crystallization step, in order to adjust the average particle size of the crystals, a step of shearing the crystallized crystals (shearing step) may be further provided. The shearing step may be performed by a so-called breakdown method that adjusts the average particle size by applying a physical impact to the crystals contained in the sugar solution to crush the crystals. In this case, the shearing step can be performed, for example, on the obtained sugar suspension by a high-pressure homogenizer (such as HV-0A1-1.5S manufactured by Izumi Food Machinery Co., Ltd.) after the crystallization by cooling the above-described sugar solution. The shearing conditions (temperature of the sugar suspension, load pressure of the homogenizer, and homogenization conditions) may be appropriately adjusted according to the average particle size of the crystals. When the shearing step is performed, the liquid after shearing can be used as the sugar suspension.

[0034] In the addition step, in one embodiment, a functional material is added to the sugar suspension. By stirring and mixing the sugar suspension and the functional material, a mixed suspension containing crystalline sugar and / or sugar alcohol, amorphous sugar and / or sugar alcohol, and the functional material can be obtained.

[0035] Functional materials are not limited as long as they are materials or components that exhibit some function in a composition (such as food, pharmaceuticals, etc.) obtained by combining with other materials. Functional materials may be materials that are affected by the surrounding environment such as moisture, heat, light, acids, oxygen, molecular motion, ultraviolet rays, electrical interactions, and physical stimuli, or may be materials that lose their function upon heating. More specifically, examples of functional materials include amino acids, peptides (including hormones), proteins (including enzymes and antibodies), fatty acids, vitamins, minerals, microorganisms (such as bacteria like lactic acid bacteria, butyric acid bacteria, natto bacteria, bifidobacteria, and actinomycetes, molds, yeasts), hormones other than peptides, fragrances, phages, antibiotics other than peptides, and the like.

[0036] The addition amount of the functional material may be 0.01 part by mass or more, 0.05 part by mass or more, or 0.1 part by mass or more, and may be 5 parts by mass or less, 3 parts by mass or less, or 1 part by mass or less, based on 100 parts by mass of the sugar suspension described above. The addition amount of the functional material can be appropriately adjusted according to the type of the functional material.

[0037] In other embodiments, the mixing step described above may be a step of obtaining a mixed suspension by preparing a solution containing crystalline sugar and / or sugar alcohol and a functional material and then performing the crystallization step described above. Further, in other embodiments, the mixing step may be a step of preparing a mixed suspension containing crystalline sugar and / or sugar alcohol, non-crystalline sugar and / or sugar alcohol, and a functional material.

[0038] Subsequently, the spray drying step will be described. The spray drying step is a step of spray drying the above-described mixed suspension under low-temperature conditions.

[0039] In one embodiment, spray drying can be performed using a spray dryer. As the spray dryer, for example, OC-16 manufactured by Okawara Chemical Industries Co., Ltd. can be used.

[0040] The low-temperature condition means a temperature lower than the temperature (for example, higher than 60°C) at which conventional spray drying was performed (for example, 60°C or lower). The low-temperature condition may be a temperature condition such that the functions of the functional material are not lost. When performing spray drying using a sugar solution as the spray liquid, it is necessary to perform spray drying at a high temperature like the conventional temperature conditions in order to obtain granules. However, in the present embodiment, since a part of the sugar solution is made into a crystalline state and a mixed suspension obtained by adding a functional material thereto is used as the spray liquid, suitable granules can be obtained even when spray drying is performed under lower-temperature conditions than before. Thereby, for example, when the functional material is an enzyme, inactivation of the enzyme due to spray drying under high-temperature conditions is suppressed. Also, when the functional material is a fragrance, volatilization of the fragrance due to spray drying under high-temperature conditions is suppressed. The fact that spray drying is performed under low-temperature conditions means that the inlet air temperature (inlet temperature) in the spray dryer is performed under the temperature conditions as described above.

[0041] In one embodiment, the inlet air temperature in the spray drying step is preferably 60°C or lower, 55°C or lower, 50°C or lower, 40°C or lower, 35°C or lower, 30°C or lower, 25°C or lower, 20°C or lower, or 15°C or lower. The inlet air temperature may be, for example, 0°C or higher, 5°C or higher, or 10°C or higher. That is, the inlet air temperature in the spray drying step may be 0 to 60°C, or may be 0 to 50°C.

[0042] The outlet air temperature (exhaust air temperature) in the spray dryer may be, for example, 50°C or lower, 40°C or lower, 35°C or lower, 30°C or lower, 25°C or lower, 20°C or lower, or 15°C or lower, and may be 0°C or higher, 5°C or higher, or 10°C or higher.

[0043] The liquid temperature of the mixed suspension in the spray drying step may be, for example, 60°C or lower, 50°C or lower, or 45°C or lower, and may be 10°C or higher, 15°C or higher, or 20°C or higher.

[0044] In spray drying, other conditions such as the supply amount of the mixed suspension, the ambient temperature, and the ambient humidity may be appropriately adjusted respectively.

[0045] For example, the atomizer rotation speed in spray drying may be 3000 rpm or more, 5000 rpm or more, or 10000 rpm or more, and may be 25000 rpm or less, 20000 rpm or less, or 18000 rpm or less.

[0046] In the spray drying step, for example, for the purpose of adjusting the moisture content of the granules, a further post-drying step may be provided. The post-drying step may be, for example, blowing air for a predetermined time against the granules adhering to the can wall in the spray dryer to further volatilize the moisture of the granules. Alternatively, it may be storing the granules obtained by spray drying in a desiccator containing silica gel for a predetermined time.

[0047] <Granules> One embodiment of the present invention contains at least one selected from the group consisting of crystalline sugars and crystalline sugar alcohols and a functional material, and the crystalline sugar and / or sugar alcohol is a granule in which a part is in a crystalline state and the other part is in an amorphous state. Since the detailed aspects of the crystalline sugar, crystalline sugar alcohol, and functional material are the same as those described above, the description thereof is omitted. Note that the "granules" in the present invention are an aggregate of particles, and the particles (granule particles) constituting the granules contain at least one selected from the group consisting of crystalline sugars and sugar alcohols and a functional material.

[0048] The granules according to one embodiment are composed of granule particles in which a part of the crystalline sugar and / or sugar alcohol is in a crystalline state and the crystalline sugars and / or sugar alcohols in this crystalline state are aggregated with each other. In this case, it is preferable that the other part (the other part) of the crystalline sugar and / or sugar alcohol is in an amorphous state and is held in the gaps formed between the aggregated crystalline sugars and / or sugar alcohols. It is also preferable that the functional material is held in the gaps formed between the crystalline sugars and / or sugar alcohols.

[0049] Agglomeration of crystalline sugars and / or sugar alcohols can be confirmed by morphological observation of the appearance of the granular particles or the cross-section of the granular particles using a scanning electron microscope (SEM) or a digital microscope. Further, the retention of the amorphous sugars and / or sugar alcohols and the functional material in the above-mentioned gaps can be confirmed by the following methods. (1) Morphologically observe the granules during heating using a differential scanning calorimeter (DSC, for example, the RealView DSC (TA7000) manufactured by Hitachi High-Tech Science Corporation). By this, it can be visually confirmed that the amorphous sugars and sugar alcohols undergo glass transition upon heating. (2) Observe the difference in polarization properties between the crystalline state and the amorphous state using a polarizing microscope (for example, the polarizing microscope (MT9200L) manufactured by Mage Techno Co., Ltd.).

[0050] The number of crystalline sugars and / or sugar alcohols (number of crystals) contained in the granular particles is, for example, 10 or more, and may be 50 or more, or 100 or more. The number of crystals may be 1000 or less. The number of crystals can be measured visually by observation with a scanning electron microscope.

[0051] From the viewpoint of maintaining the fluidity of the granules, the median diameter of the granular particles is preferably 30 μm or more, more preferably 50 μm or more, still more preferably 100 μm or more, and from the viewpoint of preventing the disintegration of the granules, it is preferably 500 μm or less, more preferably 400 μm or less, still more preferably 200 μm or less. The median diameter of the granular particles can be measured using a laser diffraction particle size distribution measuring device (for example, the SALD-2000J manufactured by Shimadzu Corporation).

[0052] From the viewpoint of excellent fluidity, the shape of the granular particles may be substantially spherical. From the viewpoint of excellent fluidity, the granular particles may have irregularities on their surfaces.

[0053] The granules according to this embodiment can be obtained, for example, by the above-described production method.

[0054] The granules according to the above-described embodiment are excellent in fluidity. Therefore, these granules are excellent in operability. Although the reason is not clear, the inventors consider that, as one factor, since the granule particles of this embodiment contain crystalline sugar and / or sugar alcohol, irregularities are formed on the surface of the granule particles, resulting in a smaller contact surface between the granule particles. Further, it is also considered that crystalline sugar and / or sugar alcohol is more stable than amorphous sugar and / or sugar alcohol and has lower hygroscopicity and adhesiveness, so that adhesion between the granule particles is suppressed. Furthermore, since the granules of this embodiment are obtained by spray drying under low-temperature conditions, the sugar and / or sugar alcohol is likely to remain in the crystalline state, and as a result, granules excellent in fluidity can be obtained even after spray drying.

[0055] In addition, since the granules according to the above-described embodiment contain crystalline sugar and / or sugar alcohol, the granule particles are less likely to deteriorate or break due to physical or mechanical stimuli, and are also excellent in the stability and storage properties of the particle structure.

[0056] Moreover, the granules according to the above-described embodiment have gaps. That is, gaps are formed inside the particles constituting the granules. Due to the gaps, the solvent easily penetrates into the granules, so that the granules of the present invention are also excellent in instant solubility and instant disintegration properties.

[0057] In addition, since these granules are obtained by spray drying under low-temperature conditions, the functions of the functional materials contained therein are less likely to be lost due to heat. That is, the functions of the functional materials are still well maintained even after the drying process. Usually, when obtaining granules by spray drying, it is difficult to obtain suitable granules unless spray drying is performed under higher-temperature conditions. However, since the granules according to this embodiment use a mixed suspension containing crystalline sugar and / or sugar alcohol as the spray liquid for spray drying, suitable granules can be easily obtained even under low-temperature conditions.

[0058] In addition, since the method for producing the granules according to the above-described embodiment can omit the step of drying by vacuum freezing or the step of heating the mixed suspension before spray drying, it is possible to produce granules containing a functional material by a method simpler than the conventional method.

[0059] The granules according to the above-described embodiment can be used, for example, as materials to be added to foods, food additives, pharmaceuticals, cosmetics, quasi-drugs or drugs, animal feeds, fertilizers, fragrances, antibiotics, soil conditioners, and the like.

Example

[0060] Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to the following examples.

[0061] <Example 1> Isomaltulose enzyme reaction solution (manufactured by Mitsui Sugar Co., Ltd.) was added to water and dissolved while heating to 80 °C with a water bath to obtain 5 kg of an isomaltulose solution (sugar solution) at 65% by mass based on the total amount of the solution. 5 kg of this isomaltulose solution was placed in a metal container, and after rapidly cooling the sugar solution to 30 °C, it was treated with a high-pressure homogenizer (manufactured by Izumi Food Machinery Co., Ltd., "HV-0A1-1.5S") at a pressure of 20 MPa and 60 Hz for 2 hours. When the treated solution (also referred to as sugar suspension A) was observed with a digital microscope (manufactured by Saito Optical Co., Ltd., "SKM-S31B-PC", magnification: 500 times), crystals of isomaltulose with a particle size of 20 to 80 μm were contained in sugar suspension A. The observation result of sugar suspension A by the digital microscope is shown in Fig. 1(a). The crystallization rate of sugar suspension A was 40%.

[0062] To the sugar suspension A, alcohol dehydrogenase (ADH) (manufactured by Oriental Yeast Co., Ltd., "Yeast-derived alcohol dehydrogenase", yeast-derived, molecular weight: 141-151 kDa) and bovine serum albumin (BSA) (manufactured by Fujifilm Wako Pure Chemical Corporation, "Bovine serum albumin") were added in an amount of 0.1% by mass based on the total solid content to obtain a mixed suspension (also referred to as mixed suspension A). At this time, the mass ratio of ADH to BSA was set to ADH:BSA = 1:2.

[0063] <Example 2> Isomaltulose (manufactured by Mitsui Sugar Co., Ltd.) was added to water and dissolved while heating to 80°C with a water bath to obtain 5 kg of an isomaltulose solution (sugar solution) containing 57.5% by mass of isomaltulose based on the total amount of the solution. 5 kg of this isomaltulose solution was placed in a metal container and rapidly cooled until the sugar solution reached 30°C. While maintaining a temperature of 35°C or lower, it was treated under the same conditions as in Example 1 using a high-pressure homogenizer. When the treated solution (also referred to as sugar suspension B) was observed with a digital microscope (magnification: 500 times), crystals of isomaltulose with a size of 20-80 μm were contained in the sugar suspension B. The observation result of the sugar suspension B by the digital microscope is shown in Fig. 1(b). The crystallization rate of the sugar suspension B was 40%.

[0064] To the sugar suspension B, trehalose (manufactured by Hayashibara Co., Ltd., "Crystalline trehalose") in an amount of 5% by mass based on the total of the solid content of the sugar suspension B and the content of trehalose was added and dissolved. Further, ADH and BSA were added in the same amounts as in Example 1 to obtain a mixed suspension (also referred to as mixed suspension B).

[0065] <Example 3> In Example 2, a mixed suspension (also referred to as mixed suspension C) was obtained in the same manner as in Example 2, except that the addition amount of trehalose was changed to an amount of 10% by mass.

[0066] [Spray drying] Mixed suspensions A, B, and C were spray-dried under the conditions shown in Table 1 using a spray dryer (manufactured by Okawara Chemical Industries Co., Ltd., "OC-16"). After spraying for 60 minutes, the granules adhering to half of the tank wall of the spray dryer were collected. Thereafter, for mixed suspension B and mixed suspension C, air was blown for an additional 30 to 40 minutes, and the granules adhering to the other half of the tank wall of the spray dryer were collected. Hereinafter, the granules collected immediately after spraying for 60 minutes are referred to as "primary dried granules", and the granules collected after air blowing are referred to as "secondary dried granules".

[0067]

Table 1

[0068] [Appearance Observation] For the primary dried granules prepared from each mixed suspension, the appearance of the granule particles was observed by a scanning electron microscope (SEM). The observation results are shown in Figure 2. Note that Figure 2(a) is the SEM image (magnification: 250 times) of the primary dried granules obtained from mixed suspension A, Figure 2(b) is the SEM image of the primary dried granules obtained from mixed suspension B, and Figure 2(c) is the SEM image of the primary dried granules obtained from mixed suspension C. As shown in each image, it can be seen that the obtained granules are formed by the aggregation of crystalline sugar (isomaltulose). In addition, when the appearance and cross-section of the granule particles were observed, an amorphous solid phase (mass) of amorphous sugar and functional material was observed in the gaps formed between the crystalline sugars.

[0069] [Moisture Content of Granules] The free water contained in each granule was measured using a near-infrared moisture meter (manufactured by Kett Science Laboratory Co., Ltd., "NIR moisture meter KJT-230"). Also, the total moisture content contained in each granule was measured by the following method. Approximately 5 g of the granules were measured using an electronic balance (manufactured by METTLER TOLEDO, "ME204"), and distilled water was further added until the total weight reached approximately 25 g, and the weight at that time was measured. After the granules were completely dissolved, the total solids in the granule solution were calculated from the refractive index measured using a refractometer (manufactured by ATAGO CO., LTD., "RX-5000α"). The difference between the initially measured granule weight and the weight of the total solids in the granule solution was calculated as the total moisture content contained in the granules. The results are shown in Table 2.

[0070]

Table 2

[0071] [Evaluation of Fluidity] Regarding the primary dried granules according to each example, the fluidity of the granules was evaluated by visual inspection and manual confirmation. The evaluation criteria were as follows. As a result, for all the granules in Examples 1 to 3, the evaluation of fluidity was ○. 〇: Flowing freely △: Flowing freely but solidifying when pressed ×: Sticky or having lumps

[0072] Furthermore, for the primary dried granules according to each example, the "flowability index" and "jetability index" proposed by R.L. Carr were calculated (Carr, R.L. "Evaluating flow properties of solids." Chem. Eng. (1965) 72 (163 - 168)). Regarding the primary dried granules of each example, the angle of repose (°) and spatula angle (°) of the granules were determined using a multifunctional powder physical property measuring instrument (manufactured by SEISHIN ENTERPRISE CO., LTD., "Multi-tester MT-02"). Regarding the primary dried granules of Example 3, the compressibility (%) and uniformity (-) were further determined, and based on Carr's theory, the indices corresponding to each measured value were obtained. By summing up the indices of each measured value, the flowability index was obtained, and the fluidity was evaluated based on the evaluation criteria of Carr described in Table 3. The above results are shown in Table 4.

[0073] Also, using the above apparatus, the angle of collapse (°) and the difference angle (°) of the primary dried granules according to each example were determined. For the primary dried granules of Example 3, the degree of dispersion (%) was further determined, and by adding the index corresponding to each measured value obtained based on Carr's theory and the index based on the fluidity index, the jetability index was obtained. Based on the Carr's evaluation criteria described in Table 3, the jetability of the primary dried granules according to Example 3 was evaluated. The above results are shown in Table 4.

[0074]

Table 3

[0075]

Table 4

[0076] [Evaluation of Enzyme Activity (1)] In carrying out spray drying, it was confirmed how much the ADH contained in the mixed suspension was inactivated over time. The mixed suspension was collected and diluted with distilled water so that the ADH concentration became 0.25 U / mL. After dilution, it was reacted with the substrate of ADH in an atmosphere of 25°C, and for the solution after the reaction, the absorbance at 340 nm was measured with a spectrophotometer (manufactured by Shimadzu Corporation, "UVmini-1240"). Taking the absorbance of the ADH reagent adjusted to 0.25 U / mL as 100%, the ratio of the absorbance at each elapsed time was taken as the activity retention rate. The change in the activity retention rate in each mixed suspension is shown in Table 5.

[0077]

Table 5

[0078] From Table 5, it was confirmed that the enzyme activity was sufficiently retained while the mixed suspensions prepared by the methods according to Examples 1 to 3 were subjected to spray drying.

[0079] [Evaluation of Enzyme Activity (2)] Using the same method as [Evaluation of Enzyme Activity (1)], the activity retention rate of ADH was measured for the granules obtained in Examples 1 to 3. The results are shown in Table 6.

[0080]

Table 6

[0081] [Evaluation of Enzyme Activity (3)] Regarding the primary dried granules according to Example 1, and the primary dried granules and secondary dried granules according to Example 2, the change in enzyme activity during low-temperature storage was confirmed. Each granule was placed in an aluminum bag with a chuck (manufactured by Seishin Co., Ltd., Japan, Ramzip AL-J), and stored for a predetermined number of days in an environment of -20°C and 4°C. Using the same method as described above, the change in the activity retention rate of each granule during low-temperature storage was measured. The results are shown in Table 7.

[0082]

Table 7

[0083] <Example 4> Trehalose (manufactured by Hayashibara Co., Ltd., "Crystalline Trehalose") was added to water and dissolved while heating to 80°C with a water bath to obtain 5 kg of a trehalose solution (sugar solution) with a Brix value (Bx) of 62. This 5 kg of trehalose solution was placed in a metal container and rapidly cooled until the sugar solution reached 30°C. While maintaining a temperature of 30°C or lower, using an ultrasonic oscillator (manufactured by SMT Co., Ltd., "ULTRA SONIC HOMOGENIZER UH-500"), it was treated at a POWER MONITER level of 5 for 15 minutes. When the treated solution (also referred to as sugar suspension D) was observed with a digital microscope (magnification: 500 times), crystals of trehalose with a size of 20 to 80 μm were contained in the sugar suspension D. The observation results of the sugar suspension D with a digital microscope are shown in Figure 3.

[0084] To 4 kg of sugar suspension D, 260 g of an aqueous sucrose solution with a Bx of 50 was added. Further, ADH and BSA were added in the same amounts as in Example 1 to obtain a mixed suspension (also referred to as mixed suspension D).

[0085] [Spray drying] Mixed suspension D was spray-dried using a spray dryer under the conditions shown below. After spraying for 60 minutes, the granules (primary dried granules) adhering to half of the wall of the spray dryer can were collected. Thereafter, air was blown for an additional 30 - 40 minutes, and the granules (secondary dried granules) adhering to the other half of the wall of the spray dryer can were collected. [Spray drying conditions] Atmospheric temperature: 28.4 - 28.6 °C Atmospheric humidity: 33 - 35% Inlet air temperature: 30.2 °C Outlet air temperature: 26.1 - 28.6 °C Supply rate: 40 - 45 mL / min Atomizer rotation speed: 15118 - 17081 rpm Air supply volume: 60 Hz Exhaust air volume: 37 Hz

[0086] [Appearance observation] Regarding the primary dried granules according to Example 4, the appearance of the granule particles was observed by a scanning electron microscope (SEM) (magnification: 1000 times). The observation results are shown in Figure 4. As shown in Figure 4, it can be seen that the obtained primary dried granules are formed by the aggregation of crystalline sugar (trehalose). Further, when observing the appearance and cross-section of the granule particles, an amorphous solid phase (mass) of amorphous sugar and functional materials was observed in the gaps formed between the crystalline sugars.

[0087] [Evaluation of fluidity] Regarding the primary dried granules according to Example 4, based on the above evaluation criteria, the fluidity of the granules was evaluated by visual inspection and manual confirmation. As a result, the evaluation of the fluidity was ○.

[0088] Furthermore, in the same manner as the method described above, for the primary dried granules according to Example 4, the angle of repose (°) and spatula angle (°) of the granules, which are indicators of fluidity, and the disintegration angle (°) and difference angle (°), which are indicators of jetability, were determined. As a result, the angle of repose was 32.5°, the spatula angle was 34.1°, the disintegration angle was 20.5°, and the difference angle was 12.0°.

[0089] [Adjustment of water activity] Granules with different water activities were prepared from the granules according to Example 4. Granules (granule X) obtained by packaging the secondary dried granules according to Example 4 with aluminum foil, and granules (granule Y) obtained by subjecting the primary dried granules according to Example 4 to reduced pressure drying at room temperature (24 - 27°C) for 20 minutes and then placing them in a desiccator humidified to 20 - 30% RH with silica gel were prepared. The water activities of granule X and granule Y were measured using a water activity measuring device (manufactured by METER, "Dew Point water activity Meter AquaLAb Series4TE"). As a result, the water activity (Aw) of granule X before the storage test shown below was 0.7561, and the water activity (Aw) of granule Y was 0.4141.

[0090] Granule X in the state of being packaged in aluminum foil and granule Y stored in a desiccator were each divided into two systems, one of which was stored at room temperature (24 - 27°C) and the other was stored in a refrigerator (4 - 8°C). That is, for each of granule X and granule Y, a system stored at room temperature and a system stored in the refrigerator were provided.

[0091] [Evaluation of enzyme activity (4)] In the same manner as the method in "Evaluation of enzyme activity (2)" described above, the absorbance at 340 nm was measured for granule X and granule Y after storage at room temperature or in the refrigerator. On the other hand, in mixed suspension D, it was diluted with distilled water so that the ADH concentration became 0.25 U / mL. After dilution, it was reacted with the substrate of ADH in an atmosphere of 25°C, and for the solution after the reaction, the absorbance at 340 nm was measured using a spectrophotometer. Taking the absorbance measured from mixed suspension D as 100%, the absorbance measured from each granule was taken as the activity retention rate. The change in the activity retention rate with the storage time is shown in Table 8.

[0092]

Table 8

[0093] <Example 5, Comparative Examples 1 - 2> Sugars (trehalose) were added to warm water and dissolved while heating to 90°C with a water bath to obtain a sugar solution with a Brix value of 62. This 90°C sugar solution was placed in a metal container and rapidly cooled until the sugar solution reached 30°C to obtain 4 kg of a sugar suspension (also referred to as sugar suspension E). On the other hand, an enzyme solution containing 0.248 g of lactate dehydrogenase (LDH) (manufactured by Oriental Yeast Co., Ltd.), 0.322 g of BSA, 130 g of phosphate buffered saline (pH 7.5), and 130 g of trehalose was prepared. This enzyme solution was added to sugar suspension E immediately after the liquid temperature reached 30°C to obtain a mixed suspension (also referred to as mixed suspension E). Note that the BSA, phosphate buffered saline, and trehalose in the enzyme solution were added as common protective components.

[0094] Mixed suspension E was spray - dried using the above - mentioned spray dryer. The granules according to Example 5 were obtained by spray - drying under the conditions of an inlet air temperature of 30.0°C and an outlet air temperature of 23.5°C. On the other hand, the granules according to Comparative Example 1 were spray - dried under the conditions of an inlet air temperature of 100.0°C and an outlet air temperature of 76.7°C, and the granules according to Comparative Example 2 were obtained by spray - drying under the conditions of an inlet air temperature of 165.0°C and an outlet air temperature of 121.4°C. The conditions of spray - drying other than temperature were unified to the following conditions in all examples and comparative examples. Air flow rate: 60.0 Hz Exhaust air flow rate: 37.0 Hz Static pressure inside the tower: Slightly positive pressure Atomizer rotation speed: 18000 rpm Device shape: Wet type Supply rate: 42 - 45 mL / min Liquid temperature of the mixed suspension: 26.9 - 28.0°C

[0095] [Appearance observation] For the granules according to Example 5 and Comparative Examples 1 to 2, the external appearance of the particles was observed by a scanning electron microscope (SEM). The observation results (magnification: 500, 1000 times) are shown in Fig. 5. Note that Fig. 5(a) shows the granules (granular particles) according to Example 5, Fig. 5(b) shows the granules according to Comparative Example 1, and Fig. 5(c) shows the observation results of the granules according to Comparative Example 2. As shown in Fig. 5(a), it can be seen that in the granules according to Example 5, crystalline sugars are aggregated and formed.

[0096] [Evaluation of Fluidity] For the granules of Example 5 and Comparative Examples 1 to 2, based on the above evaluation criteria, the fluidity of the granules was evaluated by visual observation and manual confirmation. As a result, the evaluation of the fluidity of the granules according to Example 5 was ○, while the evaluations of the granules according to Comparative Example 1 and Comparative Example 2 were both ×.

[0097] Furthermore, in the same manner as the above-described method, for the granules according to Example 5 and Comparative Example 2, the angle of repose (°) and spatula angle (°) of the granules, which are indicators of fluidity, were determined. The results are shown in Table 9.

[0098]

Table 9

[0099] [Evaluation of Enzyme Activity] For the granules of Example 5 and Comparative Example 2, it was confirmed how well the LDH activity in the granules was retained over time. Granules stored at room temperature (25°C) for a predetermined number of days were collected, and the granules were diluted with distilled water so that the LDH concentration became 0.25 U / mL. After dilution, the granules were reacted with the substrate of LDH in an atmosphere of 25°C, and for the solution after the reaction, the absorbance at 340 nm was measured with a spectrophotometer (manufactured by Shimadzu Corporation, "UVmini-1240"). Taking the absorbance of the LDH reagent adjusted to 0.25 U / mL as 100%, the ratio of the absorbance at each elapsed day was taken as the activity retention rate, and the results are shown in Table 10.

[0100]

Table 10

[0101] <Example 6, Comparative Example 3> In the method of Example 5 described above, a mixed suspension (also referred to as mixed suspension F) was obtained in the same manner as in Example 5, except that LDH was changed to ADH.

[0102] The mixed suspension F was spray-dried using the above spray dryer. The granules according to Example 6 were obtained by spray-drying under the conditions of an inlet air temperature of 30.0 °C and an outlet air temperature of 23.5 °C. On the other hand, the granules according to Comparative Example 3 were spray-dried under the conditions of an inlet air temperature of 100.0 °C and an outlet air temperature of 76.7 °C. The conditions for spray drying other than the temperature were the same as those in Example 5.

[0103] [Appearance Observation] For the granules according to Example 6 and Comparative Example 3, appearance observation was performed using a scanning electron microscope (SEM). The observation results (magnification: 500 times) are shown in Fig. 6. Note that Fig. 6(a) shows the observation results of the granules according to Example 6, and Fig. 6(b) shows the observation results of the granules according to Comparative Example 3. As shown in Fig. 6(a), it can be seen that in the granules according to Example 6, crystalline sugars are aggregated and formed.

[0104] [Evaluation of Fluidity] For the granules of Example 6 and Comparative Example 3, the fluidity of the granules was evaluated by visual observation and manual confirmation based on the above evaluation criteria. As a result, the evaluation of the fluidity of the granules according to Example 6 was ○, while the evaluation of the granules according to Comparative Example 3 was ×.

[0105] Furthermore, in the same manner as the method described above, the angle of repose (°) and spatula angle (°) of the granules, which are indicators of fluidity, were determined for the granules according to Example 6 and Comparative Example 3. The results are shown in Table 11.

[0106]

Table 11

[0107] <Example 7> Lactic acid bacterium Lb.paracasei JCM8130 T was purchased from the RIKEN BioResource Center and cultured as an inoculum. The inoculum was cultured in 500 mL of MRS liquid medium at 37 °C for 48 hours. By measuring the absorbance at 660 nm of the obtained culture solution, it was confirmed that the culture solution of lactic acid bacteria was in a steady state. The supernatant was removed from the MRS medium after culturing, and the precipitate fraction was obtained as a concentrated pellet of lactic acid bacteria. To the obtained pellet of lactic acid bacteria, 130 g of trehalose, 26.1 g of skim milk, 2.61 g of ascorbic acid, and 130 g of phosphate buffered saline (pH 7.5) were added as protective agents to obtain a lactic acid bacteria solution. The lactic acid bacteria solution was kept under stirring at room temperature of 25 °C until it was mixed with the sugar suspension described below. On the other hand, 4 kg of sugar suspension E was prepared by the same method as in Example 5. The lactic acid bacteria solution was added to the sugar suspension E at 30 °C to obtain a mixed suspension (also referred to as mixed suspension G).

[0108] The mixed suspension G was spray-dried using the above spray dryer to obtain the granules according to Example 7. At this time, all the conditions of spray drying were the same as those in Example 5.

[0109] [Observation of appearance] For the granules according to Example 7, the appearance of the granule particles was observed by a scanning electron microscope (SEM). The observation results (magnification: 1000 times) are shown in Fig. 7. As shown in Fig. 7, it can be seen that in the granules according to Example 7, the sugar in the crystalline state is aggregated and formed.

[0110] [Evaluation of fluidity] For the granules of Example 7, the fluidity of the granules was evaluated by visual observation and manual confirmation based on the above evaluation criteria. As a result, the evaluation of fluidity was ○.

[0111] Furthermore, in the same manner as the method described above, for the granules according to Example 7, the angle of repose (°) and spatula angle (°) of the granules, which are indicators of fluidity, and the collapse angle (°) and difference angle (°), which are indicators of jetability, were determined. As a result, the angle of repose was 32°, the spatula angle was 50.8°, the collapse angle was 21°, and the difference angle was 11°.

[0112] [Evaluation of viability of lactic acid bacteria] For the granules of Example 7, it was confirmed how well the lactic acid bacteria in the granules were retained over time. For the granules stored for a predetermined number of days in each environment of 4°C, 25°C, and 37°C, serial dilutions 100-fold were repeatedly performed 5 times using 2.5 mM phosphate buffered saline (pH 7.5). After dropping 1 mL of each dilution into a sterilized petri dish, 20 mL of BCP-added agar medium kept at 50°C was poured into the petri dish containing the dilution. After culturing for 72 hours in a thermostat at 37°C, the number of colonies of lactic acid bacteria formed in the petri dish was counted. From the dilution ratio, the number of lactic acid bacteria cells (CFU / g) contained in 1 g of the granules was determined by calculation. The change in the number of lactic acid bacteria cells (Log(CFU / g)) with the number of days elapsed is shown in Table 12.

[0113] [Table 12]

[0114] [Example 8] 330 g of gum arabic was completely dissolved in 500 g of warm water to prepare a gum arabic solution. The gum arabic solution was adjusted to a liquid temperature of 60°C, and 165 g of medium-chain fatty acid oil (MCT, Nisshin MCT Oil, manufactured by Nisshin Oillio Group, Ltd.) was mixed therein, and then emulsification treatment was performed at POWER MONITER level 5 using the same ultrasonic oscillator as in Example 4. As the conditions for the emulsification treatment, operation for 30 seconds and pause for 30 seconds were repeated 3 times. Thereby, an MCT emulsion was obtained. On the other hand, 4 kg of sugar suspension E was prepared in the same manner as in Example 5. The MCT emulsion was added to the sugar suspension E at 30°C to obtain a mixed suspension (also referred to as mixed suspension H).

[0115] The mixed suspension H was spray-dried using the above-described spray dryer to obtain granules according to Example 8. At this time, all the conditions for the spray drying were the same as those in Example 5.

[0116] [Observation of appearance] Regarding the granules according to Example 8, the appearance of the granule particles was observed by a scanning electron microscope (SEM). The observation results (magnification: 1000 times) are shown in Fig. 8. As shown in Fig. 8, it can be seen that in the granules according to Example 8, crystalline sugar is aggregated and formed.

[0117] [Evaluation of fluidity] Regarding the granules of Example 8, based on the above evaluation criteria, the fluidity of the granules was evaluated by visual inspection and manual confirmation. As a result, the evaluation of the fluidity was ○.

[0118] Furthermore, in the same manner as the method described above, for the granules according to Example 8, the angle of repose (°) and spatula angle (°) of the granules, which are indicators of fluidity, and the collapse angle (°) and difference angle (°), which are indicators of jetability, were determined. As a result, the angle of repose was 38°, the spatula angle was 49.8°, the collapse angle was 34°, and the difference angle was 4°.

[0119] [Example 9] 40 g of a fragrance (vanillin) was heated to 95 °C in a dry heat sterilizer to form a melt and then rapidly cooled to 30 °C. On the other hand, 4 kg of sugar suspension E was prepared in the same manner as in Example 5. 40 g of the 30 °C vanillin melt was mixed with the 30 °C sugar suspension E to obtain a mixed suspension (also referred to as mixed suspension I) (vanillin concentration in the solid content of mixed suspension I: 1.59% by mass).

[0120] The mixed suspension I was spray-dried using the above spray dryer to obtain the granules according to Example 9. At this time, all the conditions of the spray drying were the same as those in Example 5.

[0121] [Appearance observation] Regarding the granules according to Example 9, the appearance of the granule particles was observed by a scanning electron microscope (SEM). The observation results (magnification: 1000 times) are shown in Fig. 9. As shown in Fig. 9, it can be seen that in the granules according to Example 9, crystalline sugar is aggregated and formed.

[0122] [Evaluation of fluidity] Regarding the granules of Example 9, based on the above evaluation criteria, the fluidity of the granules was evaluated by visual inspection and manual confirmation. As a result, the evaluation of fluidity was ○.

[0123] Furthermore, in the same manner as the method described above, for the granules according to Example 9, the angle of repose (°) and spatula angle (°) of the granules, which are indicators of fluidity, and the collapse angle (°) and difference angle (°), which are indicators of jetability, were determined. As a result, the angle of repose was 34°, the spatula angle was 44.3°, the collapse angle was 26.5°, and the difference angle was 7.5°.

[0124] [Sensory Evaluation] In the granules according to Example 9, the aroma of vanillin was strongly retained. In order to evaluate the vanillin concentration in the granules, a sensory evaluation by the three-point discrimination method was carried out by the following method.

[0125] First, the following solutions were prepared respectively. (1) Blank: 1240 mg of trehalose was completely dissolved in 1 L of warm water. (2) Granule solution: 1260 mg of the granules according to Example 9 was completely dissolved in 1 L of warm water (dilution ratio at which the vanillin concentration becomes 0.02% if the aroma recovery rate is 100%). (3) Non-granule solution: 20 mg of vanillin and 1240 mg of trehalose were completely dissolved in 1 L of warm water (dilution ratio at which the vanillin concentration becomes 0.02%).

[0126] 10 mL of each of the solutions (1) to (3) was serially diluted (maximum dilution 256 times). 10 mL of the serial dilution solution was put into a new Falcon tube, and the dilution solution was dropped onto the tip of a filter paper (manufactured by Advantec Co., Ltd.) cut into strips, and two panelists evaluated the aroma and made a discrimination based on the three-point discrimination method. That is, it was confirmed whether the dilution solution of the granule solution or the non-granule solution could be discriminated from two blanks respectively. The results are shown in Table 13. In Table 13, ○ indicates the case where two panelists (Panel 1, Panel 2) could discriminate the aroma of the dilution solution, and × indicates the case where they could not. From the results shown in Table 13, it can be said that in the granules according to Example 9, the aroma of vanillin is sufficiently retained even after spray drying.

[0127]

Table 13

[0128] <Reference Example 1: Influence of Temperature Conditions during Spray Drying> The influence of temperature conditions in spray drying on the fluidity of granules was examined. Sugars (trehalose: sucrose 95:5) were added to warm water and dissolved while heating to 90 °C with a hot water bath to obtain a sugar solution with a Brix value of 61. This 90 °C sugar solution was placed in a metal container and rapidly cooled until the sugar solution reached 30 °C. While maintaining a temperature around 30 °C, a sugar suspension was obtained by treating it for 15 minutes at POWER MONITER level 5 using the same ultrasonic oscillator as in Example 4.

[0129] The sugar suspensions were spray-dried under the temperature conditions (inlet air temperature, outlet air temperature) shown in Table 14 below to obtain granules. The conditions for spray drying other than temperature were the same as those in Example 5.

[0130] For each granule, based on the above evaluation criteria, the fluidity of the granule was evaluated by visual observation and manual confirmation. The results are shown in Table 14.

[0131]

Table 14

[0132] <Reference Example 2: Influence of Concentration of Sugar Suspension> The influence of the concentration (Brix value) of the sugar suspension on the fluidity of granules was examined. Sugars (trehalose: sucrose 95:5) were added to warm water and dissolved while heating to 90 °C with a hot water bath to prepare sugar solutions with Brix values of 50.0, 55.0, and 61.0, respectively. Each sugar solution was placed in a metal container and rapidly cooled until the sugar solution reached 30 °C to obtain a sugar suspension.

[0133] Each sugar suspension was spray-dried using the above spray dryer to obtain granules. At this time, all the conditions for spray drying were the same as those in Example 5.

[0134] For each granule, based on the above evaluation criteria, the fluidity of the granule was evaluated by visual inspection and manual confirmation. As a result, in the granules obtained based on the sugar solutions with Brix values of 50.0, 55.0, and 61.0, all the fluidity evaluations were ○.

[0135] <Reference Example 3: Influence of Atomizer Rotation Speed during Spray Drying> It was examined how much the atomizer rotation speed in spray drying affects the fluidity of the granules. Sugars (trehalose: sucrose = 95:5) were added to warm water and dissolved while heating to 90 °C with a water bath to obtain a sugar solution with a Brix value of 61. This 90 °C sugar solution was placed in a metal container and rapidly cooled until the sugar solution reached 30 °C to obtain a sugar suspension.

[0136] The sugar suspension was spray-dried under the conditions of atomizer rotation speeds of 5000 rpm, 10000 rpm, and 18000 rpm respectively to obtain granules. The conditions for spray drying other than the atomizer rotation speed were the same as those in Example 5.

[0137] For each granule, based on the above evaluation criteria, the fluidity of the granule was evaluated by visual inspection and manual confirmation. As a result, in the granules spray-dried at atomizer rotation speeds of 5000 rpm, 10000 rpm, and 18000 rpm, all the fluidity evaluations were ○.

Claims

【Claim 1】 A step of obtaining a mixed suspension containing at least one selected from the group consisting of a crystalline sugar and a crystalline sugar alcohol and a functional material, wherein a part of the sugar and / or the sugar alcohol is contained in a crystalline state; A method for producing granules, comprising a step of spray-drying the mixed suspension under low-temperature conditions.

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