JPH0195739A - Production of readily soluble granular stevia sweetener - Google Patents

Abstract

PURPOSE:To produce a sweetener having a wide use, being readily made into an aqueous solution, by blending a stevia sweetener with alcohol-containing water in a specific ratio, heating and expanding the solution by a vacuum dryer, grinding and granulating. CONSTITUTION:Crude stevia, purified stevia or glucosyl stevioside is blended with alcohol-containing water in the weight ratio of 1:0.2-1.0 to give a concentrated solution. The solution is fed to a smoothing plate of a vacuum device, heated and dried at <=110 deg.C into an expanded and dried material having preferably <=10wt.% water content. Then the dried material is ground and granulated. Any devices may be used. A grinder having few crushing impact and causing a small amount of fine powder is preferably used and the powder is granulated to 5-150 meshes particles size to give a product. The particle diameter having a limited range is determined according to the aim of use, use and bulk density of product.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to the granulation of stevia sweeteners, and more specifically to the granulation of stevia sweeteners, which are porous and have excellent fluidity so that they can be quickly dispersed in an aqueous solution. , relates to a method for producing a dissolving porous stevia sweetener.

[Conventional technology]

In recent years, as the harmful effects of excessive intake of sugar sweeteners such as sugar sweeteners have become a problem, there has been an increasing social demand for low-calorie sweeteners. Saccharin has long been a low-calorie sweetener.

Synthetic sweeteners such as zultin and cyclamate have been used, but from a safety standpoint, they are now subject to legal regulations such as restrictions and prohibitions on their use, so a highly safe low-calorie sweetener has been developed to replace them. It is hoped that the emergence of

Against this background, various natural sweeteners, especially stevia sweetener, have excellent heat resistance and acid resistance, and the taste is very similar to that of floor sweeteners. Widely used for sugar, etc.

[Problem that the invention seeks to solve]

Stevia sweetener is an excellent natural sweetener, but the solubility of products obtained by conventional methods using drum dryers or spray dryers is problematic when dissolved in water or the like. In other words, if it is in the form of granules, it does not dissolve easily and settles on the bottom of the container or adheres to the wall of the container, and if it is in the form of fine powder, it collects in the liquid and clumps, forming what is called a mako-like shape. Once agglomerated, it does not decompose easily and takes a considerable amount of time to completely dissolve. This is particularly noticeable when the water temperature is below room temperature.

A common method for solving these dissolution problems is to secondarily granulate a fine primary product obtained using a conventional spray dryer or the like. Examples of such methods include fluidized bed granulation, crush granulation, and extrusion granulation, but in most cases, other materials other than stevia sweetener, specifically fluidized bed granulation, are used. Binders (e.g., dextrin, pullulan, etc.) or lubricants (e.g., sugar esters, glycerin fatty acid esters, lactose, bed fillers, etc.) to prevent adhesion to equipment during crush granulation and extrusion granulation. Requires. Therefore, in some cases, the granules obtained by these methods may become cloudy during dissolution,
Or coloring becomes a problem. Furthermore, the granules obtained by such a method are often easy to crumble because of their low strength, or conversely, are too strong and are therefore ineffective in improving solubility. As a result of the above, the current situation is that satisfactory results have not been obtained from the viewpoint of easy dissolution with stevia alone.

[Means and effects for solving the problem] The present invention solves the above problem by making the stevia sweetener into a product that is porous and has a certain degree of particle strength and has a constant particle size. It is something to do. Since the stevia sweetener produced according to the present invention is porous and has particle strength, when added to an aqueous liquid, water can quickly penetrate into the pores, especially at low temperatures. It can be significantly improved.

Such porous stevia sweeteners can be produced by supplying a concentrated solution of stevia sweetener under heating and reduced pressure onto a smooth plate in a vacuum dryer, or by supplying it onto a smooth plate and then heating and reducing pressure. It can be produced by expanding the powder, drying it, peeling it off from a smooth plate, pulverizing it, and then sizing it to a desired particle size.

The present invention will be explained in detail below.

The stevia sweetener related to the present invention collectively refers to crude stevia, purified stevia, and α-glucosyl stevioside. In addition, the stevia sweetener used in the present invention is a plant belonging to the Asteraceae family.
Crude stevia (components mainly include stevioside, rebaudioside, dulcoside, etc.) extracted from the leaves and stems of C. onis with water, hot water, or hydrous alcohol, and purified stevia that is purified using ion exchange resins or ultrafiltration membranes. , and further refers to α-glucosylated stevia to which glucose has been enzymatically added (eg, JP-A No. 54-5070).

Depending on the purpose, other materials other than the stevia component may be used, such as sweeteners (glycyrrhizin, thaumatin, monellin, aspartame, etc.) for the purpose of improving taste, and acidulants, to the extent that they do not significantly interfere with the formation of a porous structure. (e.g. citric acid, tartaric acid, etc.), seasonings (sodium chloride,
It is of course possible to add calcium chloride, monosodium glutamate, etc.). Furthermore, if necessary, coloring agents, flavoring agents, etc. can be added as appropriate to add variety to the sweetener's uses.

In the present invention, the concentrated solution of stevia sweetener supplied to the vacuum dryer has a stevia sweetener:water ratio of 1:0.2.
~1.0 (weight ratio, between). If the amount of water added to 1 part of the stevia sweetener is less than 0.2, it will be difficult to mix uniformly, and the state of swelling will also become unstable, resulting in inconsistent bulk density of the product. In addition, if the amount of water added to 1 part of the stevia sweetener exceeds 1 part, the liquid viscosity will decrease, so structures such as providing banks on the smooth board are required to control the state of casting on the smooth board. This is undesirable because it requires special considerations, and furthermore, the product manufacturing capacity is significantly reduced due to the increase in energy required for drying.

Regarding the water added to the stevia sweetener, water containing alcohols such as methyl alcohol, ethyl alcohol, and propyl alcohol can also be used. When the ratio of water added to the stevia sweetener is small, for example, 0.2 to 1 part of the stevia sweetener is used.
In the range of ~0.5, it becomes an effective means to reduce the viscosity of the resulting concentrated stevia solution, and the amount of energy required to dry the concentrated stevia sweetener solution by adding alcohols such as It is also possible to reduce
This leads to an increase in product manufacturing capacity. Furthermore, it is possible to control the degree of swelling to a certain extent by adjusting the alcohol content or the combination of temperature and vacuum conditions during drying. However, in this case, it is necessary to pay attention to equipment regarding ignition and recovery of alcohol.

Next, regarding the temperature during drying, a higher temperature is preferable from the viewpoint of production efficiency, but the upper limit of the temperature of the stevia sweetener solution or dried product needs to be 110° C. or lower to prevent decomposition of sweet components.

The degree of reduced pressure is set between a value corresponding to the saturated vapor pressure of water or alcohol at the drying temperature and a vacuum. The degree of porosity of this dried product depends on ■temperature, ■degree of vacuum, ■concentration of the stevia sweetener supply solution, etc.
Influencing factors other than ■ and ■ are ■ the thickness of the concentrated stevia sweetener solution on the smooth board, and ■ the extent to which water in the concentrated stevia sweetener solution to be supplied evaporates and the formation on the smooth board. There is a time required until deformation no longer occurs, but these (2) and (3) are a matter of manufacturing capacity in actual manufacturing, and it is important to decide based on each actual situation. Therefore, regarding ■ and ■, the conditions do not affect the degree of porosity of the product, that is, regarding ■, the thickness of the supplied concentrated stevia sweetener solution on the smooth plate is about several millimeters, and ■ Regarding this, a case is set in which there is no restriction on the time required for drying the supplied stevia sweetener concentrated solution until it loses its fluidity. In this case, the degree of porosity of the product can be arbitrarily adjusted by combining the conditions (1), (2), and (2) above. First, when (1) the temperature and (2) the degree of vacuum are constant, the smaller the amount of water added to the stevia sweetener, that is, the closer to 0.2, the more porous the product will be. Next, when (1) the temperature and (2) the concentration of the stevia sweetener feed solution are constant, the greater the degree of vacuum, the more porous the product will be. Next, (1) the degree of reduced pressure and (2) the case where the concentration of the stevia sweetener feed solution is constant, and the higher the temperature, the more porous the product will be. Only the amount of water added to the stevia sweetener is small, i.e. the amount of water is 0.2 to 1 of the stevia sweetener.
In cases where the drying conditions are close to 1, it is necessary to set drying conditions that do not cause extremely rapid evaporation of the added water. If drying conditions are set that causes extremely rapid evaporation of the added water, the stevia sweetener will not form blocks and the result will be a fine powder that is almost the same as that obtained with a spray dryer. The result is no result.

The method for supplying the stevia sweetener solution onto the smooth plate is as follows:
When the vacuum drying device is of a continuous type, a pressure nozzle or the like is used, but there are no particular restrictions on the shape of the nozzle.

Furthermore, if the vacuum drying apparatus is a batch type, there are of course no restrictions.

The material used for the smooth plate is polyethylene.

Polyolefins such as polypropylene, Teflon, etc. are preferred. However, in this case, in order to improve the heat transfer efficiency, it is necessary to take measures such as using a thin film of these or a composite material in which the above-mentioned material is coated on another glass/carbon fiber nonwoven fabric.

If the moisture content of the puffed and dried product thus obtained is 10% or less, the dried products will not bind to each other and there will be no problem with absorbency. Therefore, subsequent handling is easy, and the physical force required for crushing does not need to be too large, so there are no particular restrictions on the equipment for subsequent crushing and grading. However, if possible, it is desirable to use a pulverizer that has a small crushing impact force and generates less fine powder (for example, a Wheley type pulverizer that rotates at a low speed).

Furthermore, regarding the particle size of the stevia sweetener produced according to the present invention, it is of course possible to use the stevia sweetener that has just been swollen and dried, but from the viewpoint of quantitative performance and rapidity and stability of dissolution, it is preferable to use the stevia sweetener after crushing. Grind to make the particle size uniform. In this case, the particle size is preferably 5 mesh pass from the quantitative viewpoint, and 150 mesh pass from the viewpoint of rapid dissolution and stability.
Mesh On is preferable. In reality, the particle size is determined within a more limited range depending on the specific purpose or use, bulk density, etc.

〔Example〕

The present invention will be explained below with reference to Examples.

Example 1 Stevia extract [Product name: Steviafin HJ.

A mixture of 100 g of Yamaba Kokusaku Pulp Company product and 50 g of water was poured onto a stainless steel tray covered with a 0.05 nyn thick Teflon sheet, and dried in a vacuum dryer [Vacuum Dry Oven, Tokyo. placed in Rika Kikai ■ Co., Ltd.] for approximately 1 hour at a temperature of 100°C and a vacuum level of 50 Torr.
r, swelling and drying treatment. The moisture content of the sample taken out was 3% or less. Next, the obtained dried material is crushed using a pulverizer [Wiley pulverizer model WSX.

[manufactured by Honya Seisakusho ■] was used to crush the powder at low speed. Furthermore, the obtained sample was sieved using a sieve shaker. The relationship between particle size and bulk density of the sample finally obtained in this way was as shown in Table 1.

Next, Table 2 shows the results of examining the solubility of these samples in water.

II- (Note 1) Dissolution conditions: Take 50 samples of tap water at a water temperature of 5℃ and 25℃, add 300μ of the sample while stirring the tap water at a constant speed on a magnetic starch, and dissolve completely. The time until dissolution was measured.

(Average value of 5 times) (Note 2) Control product: ★1 After spray drying with a spray dryer, it was sieved.

*2 Granulated using a 1% pullulan solution as a binder in a fluidized bed granulator and then sieved.

★Dried in a 3-drum dryer and then sieved.

Example 2 α-glucosylated stevia [trade name rSK Sweet”,
10 kg of Yamaba Kokusaku Pulp Company product] and 7 kg of water were kneaded in a mixer to form a slurry. Next, this slurry was fed using a tube pump at a feeding rate of 2 kg/hr using a belt-type continuous vacuum dryer [trade name: Bellmax B V-10].
Type 1, manufactured by Okawara Seisakusho ■ Co., Ltd.], where it was expanded and dried. The swelling and drying conditions were a drying zone temperature of 110°C;
The residence time was 45 ml and the cooling zone temperature was 25° C., the residence time was 15 ml, and the vacuum degree was 10 Torr. The moisture content of the sample thus obtained (sample A) was 5% or less. Next, the dried products are sized using a sieving machine [Product name: FOR-1]
0. The mixture was pulverized using a sieve shaker [trade name: Vibro Separator, manufactured by Fukashin Kogyo ■]. The relationship between the particle size and bulk density of the obtained sample is the third
It looked like a table.

24-60 M/3 0.71-0.25 an O
, 42-0, 62 Next, Table 4 shows the results of examining the solubility in water of the following samples.

(Note 1) Dissolution conditions: Take 50 samples of tap water at water temperatures of 5℃ and 25℃, add 300μ of the sample while stirring the tap water at a constant speed on a magnetic starter, and stir until completely dissolved. The time was measured.

(Average value of 5 times) Example 3 Among the conditions for producing the puffed and dried stevia sweetener in Example 2, only the ratio of α-glucosyl stevia to water was changed to 10 kg: 5 kg, and the other conditions were changed. Samples (Sample B,
(moisture content: 5% or less) was obtained.

Next, this sample B and the sample B obtained in Example 2 were passed through a sieving machine [trade name FOR-10. Samples with various particle sizes (11 levels) were obtained by changing the crushing conditions and processing the samples at Freund Sangyo Co., Ltd.). Dissolution conditions for each of these particles: Collect 50 samples of tap water at a water temperature of 5℃, stir the tap water at a constant speed on a magnetic star sea, and add 300 μ of the sample until completely dissolved. The average value of 5 times was measured over a period of . The results are shown in the figure.

〔Effect of the invention〕

As shown in the examples, the stevia sweetener according to the present invention is different from conventional sweeteners that require time to dissolve in an aqueous solution. It can be dissolved in an extremely short time even at low temperatures. Furthermore, in the present invention, the conditions for swelling, drying, and sizing can be changed relatively easily, so products with different bulk densities and particle sizes can be manufactured depending on the use and purpose.

As a result of the above, the stevia sweetener alone can be easily used as table sugar, so it can be expected that the scope of use of the stevia sweetener will greatly expand.

[Brief explanation of the drawing]

The figure shows the relationship between particle size and required dissolution time in Example 3. Solid line... If sweetener: water = 1: 0.7, dashed line...
Sweetener: Water = 1:0.5 Patent applicant: Sanyo Kokusaku Pulp Co., Ltd.

Claims (1)

[Scope of Claims] 1. A hydrated stevia sweetener containing stevioside, rebaudioside, or α-glucosyl stevioside, wherein the ratio of sweet substance to water is 1:0.2 to 1 by weight.
．． 1. A method for producing a readily soluble granular stevia sweetener, which comprises heating the stevia sweetener with a vacuum drying device to 110° C. or lower, swelling and pulverizing the sweetener, and further grading the stevia sweetener if necessary. 2. A method for producing a readily soluble granular stevia sweetener according to claim 1, wherein the hydrated stevia sweetener contains alcohol. 3. The method for producing a readily soluble granular stevia sweetener according to claim 1 or 2, wherein the granules have a particle size of 5 to 150 mesh.