JP3513197B2 - Method for producing high purity maltitol - Google Patents

Description

Detailed Description of the Invention

[0001]

[Industrial applications]

The present invention relates to a method for producing high-purity maltitol.

[0003]

[Prior art]

Maltitol is a sugar alcohol obtained by hydrogenating a disaccharide, maltose,
Since it has various excellent properties similar to sugar, it is used for various foods, drinks, pharmaceuticals and the like.

Although many methods for producing maltitol have been proposed, among them, methods for producing high-purity maltitol that can obtain crystals and honey crystals are roughly classified into the following three types. It

That is, the first conventional method is, for example, as disclosed in Japanese Patent Publication No. 63-2439, α-
Β-amylase and isoamylase were allowed to act on a starch liquefaction solution obtained by liquefying a low concentration of starch with amylase to a low DE (dextrose equivalent) to obtain a maltose-rich saccharification solution having a maltose purity of 95 to 98%. It is the content of hydrogenating to obtain high-purity maltitol.

The second conventional method is disclosed in Japanese Examined Patent Publication No. 63-63.
-64200, Japanese Patent Publication No. 62-51120,
As disclosed in Japanese Examined Patent Publication No. 05-9080, a method of chromatographically separating a saccharified solution to obtain high-purity maltose and then hydrogenating it, that is, a maltose purity of about 75 to 85% The saccharified solution is chromatographed with an adsorbent such as an ion exchange resin to obtain, for example, a maltose fraction having a purity of 93% or more, a catalyst such as Raney nickel is used, and hydrogenation is performed by a known method per se.

Further, the third conventional method is disclosed in Japanese Patent Laid-Open No.
As introduced in the -180795 publication, 25-
After liquefying starch milk having a high concentration of 45%, saccharification conditions were selected to obtain a saccharified solution having a maltose purity of 50 to 80% or more, which was hydrogenated to give a corresponding maltitol aqueous solution, which was further chromatographed. The content is that a liquid having a maltitol purity of 87 to 97.5% is prepared by separation, and high-purity maltitol is obtained through concentration and crystallization.

As a method similar to the third conventional method, JP-A-1-93597 discloses a method of hydrogenating a saccharified solution, treating it with an enzyme, then re-hydrogenating it, and separating it by chromatography. Proposed.

[0010]

[Problems to be Solved by the Invention]

However, problems remain in the conventional production method, and it is difficult to say that it is a sufficient method in terms of economy in producing high-purity maltitol.

For example, in the first conventional method, the purity of maltose is 85 when the enzymatic reaction is carried out at an economical concentration.
There was a problem that it would be about 90%.

That is, in order to produce high-purity products such as anhydrous maltitol crystals and maltitol-containing crystals,
As described in Example 1 of Japanese Examined Patent Publication No. 63-2439, it is necessary to carry out the enzyme reaction at a low concentration of about 10% to make the maltose purity 95% or more, so that the concentration cost is high. Moreover, there was an economic problem in that relatively high amounts of expensive enzymes such as isoamylase must be used in the process.

Further, in the second conventional method, the concentration of the saccharified solution is at most about 10 to 20%, so it is necessary to concentrate it to about 40 to 70% and then perform chromatographic separation. Since the concentration will be reduced to about 30%, the economical handling concentration is 50 to 70 again.
It is necessary to conduct hydrogenation reaction after concentrating to about
After hydrogenation, deionization, and decolorization, the concentration is 35-45.
However, there is a problem that it is necessary to further concentrate before it is made into a product, that is, it is an uneconomical process that requires many concentration steps and therefore costs a lot. It was

Further, in the second conventional method, in order to improve the economic efficiency as much as possible, the maltose-containing low-purity fraction obtained by the chromatographic separation is not discarded but treated economically by some method. There was also the issue of needing effective use.

Further, in the third conventional method, as in the case of the second conventional method, the cost of concentration is high, and the maltitol-containing low-purity fraction obtained by chromatographic separation is economically and effectively used. There was a problem that it had to be dealt with.

Further, Japanese Laid-Open Patent Publication No. 1-58200, which is similar to the third conventional method.
The method of No. 93597 has a problem in that, in addition to the complexity of passing through the hydrogenation reaction twice, a chromatographic separation step is required, the liquid concentration is lowered, and the concentration cost is increased.

That is, in summary, as a method for obtaining high-purity maltitol for producing anhydrous crystalline maltitol and maltitol-containing crystals, it is necessary to lower the reaction concentration in the process using a special enzyme. There is a problem that it is economically disadvantageous due to the fact that the cost of the enzyme is high, and the use of an inexpensive general-purpose raw material requires the adoption of a chromatographic separation process, so the concentration of the liquid decreases and the concentration cost increases. The problem was that it would be expensive.

Therefore, high-purity maltitol having a purity of 90% by weight or more, particularly 95% by weight or more, can be economically produced from an inexpensive raw material having a maltose purity of 80% by weight or more, especially about 80 to 90% by weight. Although there was a method that was expected to be the most advantageous, there was no method that could be advantageously performed because of technical difficulties, so there was a need for steps using special enzymes and chromatographic separations. It has been desired to develop a method capable of economically advantageous production of high-purity maltitol without going through steps and the like.

[0020]

[Means for Solving the Problems]

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, after hydrogenating an inexpensive starch saccharified product having a maltose purity of 80% by weight or more, glucoamylase or yeast is allowed to act on the economy, thereby improving the economy. The present invention has been completed by succeeding in significantly improving the maltitol purity by a general method.

First, in the production of high-purity maltitol, (1) the first step of hydrogenating a starch saccharified product having a maltose purity of 80% by weight or more; and (b) the hydrogenated product obtained in the first step. Degree of polymerization of 3 by acting glucoamylase or by acting glucoamylase and debranching enzyme
Second step of hydrolyzing the above sugar alcohol, c) second
A method for producing high-purity maltitol, characterized in that maltitol having a purity of 90% by weight or more is obtained by sequentially passing through the third step of allowing yeast to act on the hydrolyzate obtained in the step, and the above-mentioned three steps. .

Secondly, in the production of high-purity maltitol, (a) the first step of hydrogenating a starch saccharified product having a maltose purity of 80% by weight or more, and (b) the hydrogenated product obtained in the first step. Glycoamylase and yeast are allowed to act, or glucoamylase, debranching enzyme and yeast are allowed to act to hydrolyze sugar alcohols having a degree of polymerization of 3 or more.
A method for producing high-purity maltitol, characterized in that maltitol having a purity of 90% by weight or more is obtained by sequentially passing through the second step of fermentation and the above-mentioned two steps.

Thirdly, the hydrogenated product obtained in the first step has a reducing sugar content of 0.01% by weight or more and less than 2% by weight, as described in the above first or second aspect. Method for producing high-purity maltitol.

Fourth, the high-purity mulch according to any one of the first to third, wherein the yeast is one or more selected from the group consisting of baker's yeast, alcohol yeast and sake yeast. Toll manufacturing method.

The starch saccharification product used here is required to have a maltose purity of 80% by weight or more. When the purity is less than 80% by weight, the resulting maltitol has a purity of 90%. This is because the weight may not be exceeded.

When maltitol having a purity of less than 90% by weight is used, anhydrous crystalline maltitol or maltitol-containing malt crystals cannot be produced in many cases.

However, except that the purity of maltose is 80% by weight or more, there are no particular restrictions on the manufacturing method, the origin of the raw materials, the manufacturing method, whether liquid or solid, and the like. Liquid may be used, or it may be one obtained by adding chromatographic separation, membrane separation, crystallization operation, etc. to the sugar liquid, and commercially available inexpensive maltose can be advantageously used, but components other than maltose As such, the presence of a large amount of maltotriose or a component having a larger size is more advantageous because the effect of the present invention tends to be exhibited more remarkably.

The fact that there is no special restriction other than that the maltose purity is 80% by weight or more means that it is produced in a large amount by practically adopting an economical saccharification concentration of 20 to 40%. This means that commercially available maltose can be adopted, and it can be said that the method has significantly greater economic progress than the conventional method.

In the present invention, hydrogenation is performed on a starch saccharification product, that is, an aqueous solution of maltose having a purity of 80% by weight or more. However, if the sugar solution is not decomposed unnecessarily and the hydrogenation reaction proceeds, There are no particular restrictions on hydrogen addition conditions such as concentration, type of catalyst, amount of catalyst, catalyst addition timing, reaction temperature, reaction time, hydrogen pressure, hydrogen addition reaction method, and the like.

However, generally, in order to carry out hydrogenation economically, the concentration of the maltose aqueous solution is preferably about 40 to 70%, the reaction temperature is about 100 to 160 ° C., and the hydrogen pressure is 50 to 50%. About 200 kg / cm ² is an advantageous condition, and Raney nickel and various precious metal catalysts are often used as the hydrogenation catalyst.

In the hydrogenated product obtained by examining the conditions in this manner, the original sugars become the corresponding sugar alcohols with almost no decomposition by heat or acid, hydrolysis and the like. Alternatively, in order not to reduce the yield in the second and third steps, it is preferable that the unreduced component is not contained extremely extremely, and the preferable content range of the unreduced component is 0.01.
˜5 wt%, and more preferably 0.05 to 2 wt%, considering the mildness of the hydrogenation reaction conditions.

Before subjecting the hydrogenated product obtained in the first step of the present invention to the second step or the second or third step of the present invention, decolorization and deodorization with activated carbon and deionization and decolorization with an ion exchange resin are carried out. The second step or the second and third steps of the present invention can be smoothly carried out by carrying out each of the above, but one of the major features of the present invention is that the purification operation using this activated carbon or ion exchange resin is not always necessary. Therefore, even if the refining operation is not performed, there is no particular inconvenience in the subsequent operation.

The glucoamylase used in the present invention has a usual enzyme reaction environment, that is, a temperature of about 25 to 60 ° C., a pH of 4 to 7, a substrate concentration, that is, a hydrogenated substance concentration of 20 to 60 ° C.
When it is 60%, it should have the ability to act from the exo side of the hydrogenated oligosaccharide molecule or hydrogenated polysaccharide molecule in the hydrogenated product to hydrolyze α1-6 bond and α1-4 bond. For example, although there are no other restrictions, it can be advantageously used because, among others, fungi-derived substances such as Rhizopus and Aspergillus are easily available.

When glucoamylase is used alone or in combination with debranching enzyme in the present invention, the solid content of hydrogenated product is 1%.
4 units (u) as activity of glucoamylase per g
Approximately ~ 40u is advantageous as the amount to be used, and when it is less than 4u, the components of large molecules do not decrease, and the time required for the enzyme reaction tends to be long, which is not preferable from the viewpoint of production efficiency. In that case, the effect of improving the purity of maltitol commensurate with the increase in the amount of enzyme is often not obtained, which is not preferable from the economical aspect.

Debranching enzymes are glycogen, amylopene
A general term for a group of enzymes that hydrolyze α1-6 bonds in cutin.
The debranching enzyme used in the present invention has the ability to hydrolyze a hydrogenated oligosaccharide molecule or a hydrogenated polysaccharide molecule α1-6 bond in a hydrogenated product under the same environment as that of glucoamylase. If it exists, there are no other restrictions, but it acts from the End side of the molecule and α1-
As a substance having the ability to hydrolyze 6 bonds, there are isoamylase derived from bacteria such as Aerobacter and pullulanase derived from bacteria.

When a debranching enzyme is used in the present invention, a large amount of maltitol molecules can be released from hydrogenated oligosaccharides and hydrogenated polysaccharides by using it together with glucoamylase, which is preferable. It is appropriate that the use amount of 0.4 u to 4 u as the activity of pullulanase per 1 g of the solid content of the hydrogenated product is 0.
In the case of less than 4u, the branched structure does not decrease,
It is not preferable because the enzyme reaction requires a long time.
When it is used in excess of u, it is uneconomical because a decrease in the branched structure commensurate with the amount of enzyme is not observed.

When isoamylase is used as the debranching enzyme, the same amount of enzyme may be used, but in many cases a slightly higher enzymatic activity is required than in the case of pullulanase.

The yeast used in the present invention can be used under normal fermentation conditions,
That is, as long as it has a function of producing alcohol and carbon dioxide by fermenting sugars such as glucose released as a result of the enzyme reaction under the conditions of a substrate concentration of 20 to 60% and a temperature of 25 to 40 ° C. Yeast may be used, but among them, Saccharomyces cerevisiae (Sacch
Each strain belonging to Aromyces cerevisiae can be advantageously used for the reason that the effects of the present invention can be sufficiently exhibited, and among others, baker's yeast, alcohol yeast, sake yeast, and brewer's yeast are advantageous.

The amount of the yeast used in the present invention is 0.1 to 1 g of the solid content of the fermentation reaction product as the dry yeast weight.
1% by weight is preferable, but if it is less than 0.1% by weight, unreduced sugar may remain in the maltitol product, or it may take a long time to fully ferment. It is not preferable, and if it is used in excess of 1% by weight, more yeast than necessary to assimilate the unreduced sugar will be consumed, which is economically meaningless and is not preferable.

In carrying out the present invention, it is possible to act the yeast simultaneously with the enzymatic reaction in the second step, in which case the time for acting the yeast can be saved and the number of steps is reduced by one. By doing so, it is necessary to suppress the temperature of the enzymatic reaction to about 25 to 40 ° C. so as not to impair the activity of yeast, so that glucoamylase can be used rather than the case of allowing yeast to act in the third step. It is desirable to use a slightly higher amount of debranching enzyme.

The enzyme reaction according to the present invention and the assimilation reaction by yeast can be carried out not only in a batch system but also continuously in a fixed bed system by adhering the enzyme or yeast to a carrier. In that case, high production efficiency and labor saving of operation can be realized.

As described above, by carrying out the present invention in which the steps are not difficult to carry out, the effect of the present invention can be obtained with almost no decrease in concentration, which is inevitable by adopting the conventional chromatographic separation method. Although a remarkable improvement in the purity of maltitol can be obtained economically, for example, when a commercially available maltose having a purity of 90% by weight is used, the purity is 96 to
98% by weight of maltitol has a purity of 97.5 to 98.% when commercially available maltose having a purity of 95% by weight is used.
About 5% by weight of maltitol is obtained.

Therefore, after this, various foods and drinks are processed by known processes such as mixing, kneading, dipping, infiltration, spraying, spraying, drying, coating, coating, pouring, crystallization and solidification. The high-purity maltitol obtained by the present invention can be contained in feeds, cosmetics, pharmaceuticals, molded products, etc. by applying the process until the product is completed,
It is also possible to produce anhydrous crystalline maltitol or maltitol-containing crystals by a process known per se.

[0045]

[Example 1]

A commercially available maltose 70 having a sugar composition of 90.7% by weight of maltose (hereinafter, simply referred to as%), 0.5% of glucose and 8.8% of oligosaccharide having 3 or more sugars.
% Aqueous solution [Nippon Shokuhin Kako Co., Ltd.] 1.55 kg and water 20
Raney nickel catalyst (40 g) was added to 0 g of the mixed solution, and the pH was adjusted to 7 with an aqueous sodium hydroxide solution, and then the volume was adjusted to 2.
Put in a stainless steel autoclave with 4 liters of electromagnetic stirring paddle type stirring blades, hydrogen pressure 150 kg / cm ² ,
The hydrogenation reaction, which is the first step, was performed at a stirring speed of 700 rpm and a temperature of 130 ° C. for 50 minutes.

After completion of the reaction, the contents are taken out by cooling,
After the catalyst was removed by filtration to obtain a hydrogenated liquid, the composition was measured by liquid chromatography to find that sorbitol was 1.0
%, Maltitol was 90.4%, sugar alcohol having a degree of polymerization of 3 or more was 8.6%, and unreduced sugar was measured to be 0.02%.

Next, the concentration of the hydrogenated solution was adjusted to 40%, 500 g of which was placed in a 1-liter three-necked flask, and 0.8 ml of commercially available glucoamylase [Silvarase manufactured by Nagase & Co., Ltd.] was added. [26 as glucoamylase
40 unit (u) and 240 u as a mixture of pullulanase] is added to adjust the pH to 6, and the enzyme is allowed to act for 24 hours at 55 ° C. to perform the second step, after which the solution is heated to 95 ° C. to heat the enzyme. As a result of measuring the sugar composition of the enzyme reaction solution obtained after inactivation, sorbitol 1.5%, maltitol 93.4%, sugar alcohol having a degree of polymerization of 3 or more was 0.8%.
%, And glucose was 4.3%.

Further, the enzyme reaction solution was kept at 36 ° C., 1.2 g of baker's yeast was added, and the yeast was allowed to act for 24 hours while stirring to carry out the third step. Then, powdered activated carbon [Takeda Yakuhin K.K. ), Shirasagi] 4g and heated to 50 ℃ 3
The filtrate obtained by stirring for 0 minutes and filtering was desalted with an ion exchange resin and concentrated to 70% to obtain 257 g of the highly purified maltitol of the present invention.

The composition of maltitol was 1.5% sorbitol, 97.6% maltitol, and 0.9% sugar alcohol having a degree of polymerization of 3 or more.

[0051]

Example 2

A hydrogenated solution having a concentration of 40% was prepared in the same manner as in Example 1, 500 g of which was placed in a three-necked flask having a volume of 1 liter, and commercially available glucoamylase [Amano Pharmaceutical Co., glucozyme] was used. 0.8 ml (3520 u as glucoamylase) was added, pH was adjusted to 6.0 and the enzyme was allowed to act for 24 hours at 55 ° C. As a result, sorbitol was 1.6%, maltitol was 92.6%, and the degree of polymerization was An enzyme reaction solution having a composition of 1.9% of sugar alcohol of 3 or more and 3.9% of glucose was obtained.

Next, the enzyme reaction solution was heated to 95 ° C. to lose the enzyme activity, 1.2 g of commercially available baker's yeast was added while keeping the temperature at 36 ° C., and the yeast was allowed to act for 24 hours, then 4 g of powdered activated carbon [Takeda Made by Yakuhin Kogyo Co., Ltd., Shirasagi]
After stirring at 0 ° C. for 30 minutes, the activated carbon was filtered off, desalted with an ion exchange resin, and concentrated to 70% to obtain 260 g of the highly purified maltitol of the present invention.

The composition of the maltitol was 1.7% sorbitol, 96.3% maltitol, and 2.0% sugar alcohol having a degree of polymerization of 3 or more.

[0055]

Example 3

40% concentration prepared in the same manner as in Example 1
Commercially available glucoamylase for hydrogenated liquid of Nagase & Co., Ltd.
Manufactured by Sylvalase] 2 ml and commercially available baker's yeast 1.2 g
Was added and the pH of the mixture was adjusted to 6.0, and the mixture was stirred at 36 ° C. for 24 hours to allow the enzyme and yeast to act. Then, the mixture was heated and stirred at 95 ° C. for 5 minutes and then cooled to measure the composition. The composition of the obtained high-purity maltitol of the present invention was 1.4% sorbitol, 97.1% maltitol, and 1.5% sugar alcohol having a degree of polymerization of 3 or more.

[0057]

Example 4

Hydrogenation reaction temperature is 120 ° C., hydrogen pressure is 1
00 kg / cm ² , the amount of Raney nickel catalyst is 30 g,
As in Example 1, except that the reaction time was 60 minutes, sorbitol was 1.0%, maltitol was 89.3%, sugar alcohol having a degree of polymerization of 3 or more was 8.5%, and unreduced sugar was 1%. A hydrogenation reaction solution of 0.2% was obtained.

The second step and the third step were carried out in the same manner as in Example 1, and the high-purity maltitol 254 of the present invention having a concentration of 70% was used.
As a result, sorbitol was 1.9%, maltitol was 97.1%, and sugar alcohol having a degree of polymerization of 3 or more was 1.0%.

[0060]

Example 5

Baker's yeast is sake yeast [Oriental yeast
Co., Ltd., water content 50%] 4.0 g in the same manner as in Example 1 except that the high purity maltitol of the present invention at a concentration of 70% was obtained. Was 1.4% in sorbitol, 97.7% in maltitol, and 0.9% in sugar alcohol having a degree of polymerization of 3 or more.

[0062]

Example 6

Example 1 except that a commercially available 70% maltose aqueous solution having a sugar composition of 86.2% maltose, 1.6% glucose, 12.2% oligosaccharides having 3 or more sugars was used as a raw material. As a result of passing through the first step in the same manner as above, sorbitol was 1.7%, maltitol was 86.1%, and sugar alcohol having a degree of polymerization of 3 or more was 12.2%.

Then, the second procedure was carried out in the same manner as in Example 1 except that 1.2 ml of sylvalase was used as the glucoamylase.
Perform the process, 1.8% sorbitol, 85.8% maltitol, 4.3% sugar alcohol with a degree of polymerization of 3 or more
Then, an enzyme reaction solution having a composition of glucose of 8.1% was obtained.

Further, the third step was carried out in the same manner as in Example 1 except that the stirring time was 48 hours to obtain a high-purity maltitol aqueous solution of the present invention having a concentration of 70%. Its composition was sorbitol. Was 2.0%, maltitol was 93.3%, and sugar alcohol having a degree of polymerization of 3 or more was 4.7%.

Next, the high-purity maltitol was heated to 60 ° C., and 1 g of maltitol-containing crystal having a purity of 96.5% [Amalti MR100 manufactured by Towa Kasei Kogyo Co., Ltd.] was added and gently stirred. While cooling to 30 ° C. over 48 hours, crystallization was performed to obtain a maltitol mass kit.

The mass kit was filtered with a basket type centrifuge and dried under reduced pressure at 80 ° C. to obtain 61.5 g of anhydrous crystalline maltitol.

As a result of measuring the composition of the obtained anhydrous crystalline maltitol, sorbitol 0.5% and maltitol 9 were obtained.
The content was 8.2% and sugar alcohol having a degree of polymerization of 3 or more was 1.3%.

[0069]

Example 7

257 g of a high-purity maltitol aqueous solution having a concentration of 70% obtained by repeating the same operation as in Example 1 was heated to 60 ° C. to obtain 1 g of anhydrous crystalline maltitol having a purity of 99.9%.
Is added as a seed crystal, cooled to 30 ° C. over 36 hours with gentle stirring for crystallization to form a maltitol mass kit, then filtered with a centrifuge and dried at 80 ° C. under reduced pressure. Thus, 98.3 g of anhydrous crystalline maltitol was obtained.

As a result of measuring the purity of this anhydrous crystalline maltitol, it was 99.95%.

[0072]

[Comparative Example 1]

Other than using 3 parts by weight of water, Japanese Examined Patent Publication No. 63-24
Although it was attempted to heat-gelatinize according to the method described in Example 2 of JP-A No. 39, the viscosity was extremely high, so that it could not be handled unless liquefied to a DE of about 5 to 10, and the DE could not be suppressed. However, it was impossible to produce high-purity maltose in the subsequent steps.

[0074]

【The invention's effect】

As described above, by carrying out the present invention, saccharification treatment is carried out at a high concentration, which is economically advantageous,
It is possible to improve the maltitol purity economically by using a commercially available cheap raw material having a maltose purity of about 80 to 90%, which does not go through a chromatographic separation operation, so that the concentration is not significantly lowered, and As a result, anhydrous crystalline maltitol and maltitol-containing dense crystals can be prepared from the high-purity maltitol obtained by the present invention by a method known per se.

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-4-271793 (JP, A) JP-A-4-158795 (JP, A) JP-A-2-119789 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) C12P 1/00-41/00 CA / BIOSSIS / MEDLINE / W PIDS (STN)

Claims (4)

(57) [Claims] 1. In the production of high-purity maltitol, (1) a first step of hydrogenating a starch saccharified product having a maltose purity of 80% by weight or more, and (b) a glucoamylase added to the hydrogenated product obtained in the first step. Or the action of glucoamylase and debranching enzyme to hydrolyze a sugar alcohol having a degree of polymerization of 3 or more, and c) the action of yeast on the hydrolyzate obtained in the second step. A process for producing high-purity maltitol, characterized in that maltitol having a purity of 90% by weight or more is obtained by sequentially passing through the above-mentioned three steps. 2. In producing high-purity maltitol, a) a first step of hydrogenating a starch saccharified product having a maltose purity of 80% by weight or more, and b) a glucoamylase added to the hydrogenated product obtained in the first step. And a yeast, or a glucoamylase, a debranching enzyme, and a yeast to act to hydrolyze and ferment a sugar alcohol having a degree of polymerization of 3 or more, and a purity of 90 A method for producing high-purity maltitol, which comprises obtaining maltitol in an amount of at least wt%. 3. The high-purity mulch according to claim 1, wherein the hydrogenated product obtained in the first step has a reducing sugar content of 0.01% by weight or more and less than 2% by weight. Toll manufacturing method. 4. The production of high-purity maltitol according to claim 1, wherein the yeast is one or more selected from the group consisting of baker's yeast, alcohol yeast and sake yeast. Method.