JPS61219392A - Production of branched oligosaccharide syrup by condensation reaction at elevated temperature - Google Patents

Abstract

PURPOSE:An enzyme capable of effecting condensation reaction between saccharides is allowed to act on aqueous glucose to enable high-efficiency, economical production of the titled syrup which is used in food products or medicines, it has low sweet taste. CONSTITUTION:Glucoamylase from Aspergillus niger or Rhizopus is added to aqueous glucose of more than 60% solid concentration in an amount of 0.05-3.0% on the solid basis and is allowed to act on the glucose at 4-6pH over 55 deg.C to form branched oligosaccharides such as isomaltose or panose. The resultant reaction mixture is used as a branched oligosaccharide syrup or, when necessary, saccharides other than branched oligosaccharides such as glucose are removed to give a branched oligosaccharides syrup of increased concentration.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention has a low sweetness and has an anti-aging effect and an effect of improving the preservability of foods and drinks such as confectionery, and is particularly useful as a sweetener that has an anti-caries effect. The present invention relates to a method for producing branched oligosaccharide syrup that can be used for products, medicines, etc.

[Conventional technology]

In recent years, as people's tastes have diversified, there has been a so-called shift away from sweet tastes.At the same time, as interest in health has increased, sugar has been avoided and other low-calorie sweeteners have come to the fore. Ta.

There are a variety of low-calorie sweeteners available, both natural and synthetic, but branched oligosaccharides are indigestible, have low caries properties, and have other physiological properties, making them useful in foods, drinks, pharmaceuticals, etc. It is a material that can be used in a wide range of applications. Until now, such saccharides have not been industrially produced, and only isomaltose and the like have been supplied as expensive reagents.

The present inventors have discovered that the α-
Focusing on so-called branched oligosaccharides containing 1,6 bonds, he invented and filed an application for an industrial and economical production method (Japanese Patent Application No. 59-245470).

According to the above-mentioned industrial production method invented by the present inventors, by utilizing the condensation reaction of saccharides, it is possible to obtain a product containing about 40% (solid content) of branched oligosaccharides in the form of syrup. By further refining this syrup, it has become possible to obtain a high-concentration syrup in which the concentration of branched oligosaccharides has been increased to approximately 1.4% (based on solid content). The branched oligosaccharides contained in this are mainly isomaltose,
This is followed by panose, isomaltotriose, and the like.

Such sugar syrup products have hardly ever existed on the market, and it is expected that their uses and demand will continue to expand due to the properties of branched oligosaccharides mentioned above.

[Problem that the invention seeks to solve]

The present invention is a method for producing branched oligosaccharide syrup invented by the present inventors, in which the condensation reaction of saccharides is proceeded more efficiently and branched oligosaccharide syrup is obtained more economically.

[Means for solving problems]

In the present invention, an aqueous glucose solution with a solid content concentration of 60% or more is used as a substrate, and an enzyme having a sugar condensation action is applied to this at a high temperature of 55°C or higher to produce branched oligosaccharides in the aqueous solution. This is a method for producing branched oligosaccharide syrup by further separating and removing saccharides other than branched oligosaccharides if necessary. The term "branched oligosaccharide" as used herein is a general term for oligosaccharides having α-1,6 bonds of glucose molecules, such as isomaltose, panose, and isomaltotriose.

As the enzyme having the action of condensing sugars used in this method, glucoamylase is usually selected from the viewpoint of easy availability and ease of use. Examples of glucoamylase include those originating from the genus Aspergillus, such as Aspergillus niger (for example, AMG 300L manufactured by Novo);
There are some enzymes that originate from microorganisms of the genus Rhizopus (for example, Sumizyme manufactured by Nippon Chemical Co., Ltd.), but when these enzymes are used in the starch hydrolysis reaction for glucose production, which is the most common use, they are used in Aspergillus microorganisms. - Enzyme deactivation occurs when the temperature exceeds 60°C for Niger-based glucoamylase and 55°C for Rezobus-based glucoamylase, making it practically unusable at temperatures higher than these.

However, the present inventors have surprisingly discovered that when these enzymes are made to act on a highly concentrated sugar solution, the enzymes do not deactivate even if the temperature exceeds the above range, but rather the reaction is accelerated. The present invention was completed. That is, as shown in Figure 1, when glucoamylase originating from Aspergillus niger (AMG300L manufactured by Novo) is applied to an aqueous solution with a high glucose concentration, the enzyme is not deactivated even at high temperatures of 60°C or higher, and even at high temperatures As the temperature increases, the production rate of branched oligosaccharides actually increases. Enzyme deactivation is sO'
This occurs as the reaction time increases at temperatures above c.

The same is true for glucoamylase originating from microorganisms of the genus Rhizopus; the production rate of branched oligosaccharides accelerates at temperatures above 55°C, where this enzyme is thought to be inactivated, and finally begins to become inactive at temperatures above 80°C.

Such behavior of the enzyme in the present invention has not been predicted in the past, and the industrial benefits of utilizing this behavior are large.

In other words, it brings about many effects such as increasing the reaction rate by raising the reaction temperature, improving workability by reducing the viscosity of the liquid, and preventing undesirable side reactions by suppressing the actions of other enzymes. It is.

The amount of enzyme added is about 0.05 to 3.0% (based on solid content).
The reaction pH is 4.0 to 6.0, and these conditions may be according to the usual usage of these enzymes.

The glucose aqueous solution used as a substrate must have a solid content concentration of 60% or more, and as the solid content concentration increases, the amount of branched oligosaccharides produced increases. When the solid content concentration is 85%, the amount of branched oligosaccharides produced reaches 60% or more (relative to solid content).

Furthermore, as the solid content concentration increases, the heat resistance of the enzyme improves. As mentioned above, it begins to deactivate when the temperature exceeds 80°C.

The solid content of the substrate preferably contains 70% or more of glucose, and may also contain other disaccharides, trisaccharides, and the like. Examples of scale-like substrates that can be used practically include glucose crystal dissolution solution, purified glucose solution, etc., as well as honeydew after collecting glucose crystals and isomerized sugar solution, which are conventionally considered as by-products in glucose production. Examples include raffinate after separating fructose. These are as they are,
Alternatively, it can be adjusted to contain a predetermined solid content and glucose content and used as a raw material for the present invention.

The thus obtained sugar solution is a mixed sugar solution containing branched oligosaccharides such as isomaltose, panose, and isomaltotriose, as well as glucose, maltose, and the like. This can be used as it is as a branched oligosaccharide syrup, or, if necessary, can be further processed by the following method to obtain a branched oligosaccharide syrup with a higher concentration.

(1) A method of concentrating a sugar solution and slowly cooling it to crystallize and remove glucose, etc.

(2) A method of adding salt to a sugar solution to crystallize and remove glucose-salt double salt crystals.

(3) A method in which saccharides other than branched oligosaccharides are precipitated and removed by adding an organic solvent such as alcohol or acetone to a sugar solution.

(4) A method of removing saccharides other than branched oligosaccharides using molecular fractionation chromatography such as an activated carbon column or gel filtration, or ion exchange chromatography using an ion exchanger.

(5) A method of assimilating sugars other than branched oligosaccharides by allowing yeast to act on a sugar solution.

〔Example〕

Example 1 A commercially available glucoamylase originating from Aspergillus niger (manufactured by Novo, AMG 300L) was added to a high purity glucose solution (DE 97.5, manufactured by Showa Sangyo ■) with a concentration of 75% at a solid content of 0.6% (V /W), and the reaction was carried out for 72 hours at a pH of 4.5 and a reaction temperature of 60.65.70.75.80°C to obtain the reaction products shown in the table below.

Table 1 Substrate branched oligosaccharides were not analyzed.

Example 2 A commercially available glucoamylase originating from the genus Rhizopus (manufactured by Shin Nippon Kagaku ■, Sumiteam) was added to a high purity glucose solution (DE 97.6, Showa Sangyo ■i1) with a concentration of 75% to a solid content of 0.9.
% (W/W), the pH was adjusted to 4.8, and the reaction temperature was set to 55.
The reaction was carried out at each temperature of 60, 65 and 70.75°C for 120 hours to obtain the reaction products shown in the table below.

Table 2 Analysis was performed using high performance liquid chromatography.

Example 3 The following four types of substrates were prepared to a concentration of 75%, and commercially available glucoamylase (manufactured by Novo (AMG 300L)) was added to a concentration of 0.6%.
% (V/W) and reacted at 70°C + I) H4,5 for 120 hours to obtain a branched oligosaccharide syrup as shown in the table below.

Type of substrate (each substrate was manufactured by Showa Sangyo) (1)
Crystalline glucose solution (glucose purity 99.8%)
(2) Purified glucose solution (95.0%) (3) Honey obtained by separating crystals (92.1%) (4) Raffinate obtained by chromatographic separation of isomerized sugar syrup (83.6%) Table 3 Substrate Branched sugars were not analyzed.

Example 4 The remaining honey from which the glucose crystals were removed (manufactured by Showa Sangyo ■) was adjusted to a concentration of 75%, and a commercially available glucoamylase (manufactured by Novo Corporation, AMG300L) originating from Aspergillus niger was added at a solid content of 0.5%, and the pH was adjusted to 4. , 5. The reaction was carried out at 70°C for 96 hours to obtain the products shown in the table below.

Table 4 This reaction product was purified using activated carbon and ion exchange resin and concentrated to a concentration of 60%, and then distributed using a column packed with a styrene-based strongly acidic Na-type cation exchange resin (Amberlite G-102). Single I by chromatography! The following high purity branched oligosaccharide syrup was obtained.

Table 5 Column: 50 DragonφX 1000 Dragonφ
(Na: Loaded sugar amount: 50g (dry matter) Flow rate: S V =0.09hr-” Example 5 Hydrous crystalline glucose (manufactured by Showa Sangyo 01) was melted to a concentration of 60.70, 75, and 80.85%. Commercially available glucoamylase (manufactured by Novo, AMG 300L) derived from Aspergillus niger was added at a solid content of 1.0% (V/W), and reacted at pH 4.5 and 75°C for 120 hours. The reaction products shown in the table were obtained.

Table 6 (Table 6) The parentheses in the table represent the content of branched sugars in saccharides of each degree of polymerization.

〔Effect of the invention〕

The present invention provides an industrial method for efficiently producing branched oligosaccharide syrup.

The branched oligosaccharide syrup obtained in this way has a mild sweetness that is lower than that of sugar, has anti-aging effects, and has the effect of improving shelf life, so it has a wide range of uses as a sweetener or flavor improver for various foods. be. Furthermore, because it has an anti-caries effect, it is widely used as a sweetener to prevent tooth decay. In addition, branched oligosaccharides have the effect of suppressing the crystallization of sugars, so sugar, glucose, and high-fructose sugar are used.

It can also be used as a crystallization inhibitor by adding a small amount to a sugar solution such as maltose.

[Brief explanation of drawings]

Figure 1 shows 0.6 glucoamylase originating from Aspergillus niger on a substrate with a solid concentration of 75% (95% glucose).
% (relative to solid content) is a graph showing the amount of branched oligosaccharide produced versus reaction time at each reaction temperature. Figure 1: A・'day (Japanese) Procedural amendment May 29, 1985 Patented in 1960 Kinoro 61248 2 Title of invention Method for producing branched oligotang syrup by high-temperature condensation reaction 3 Person making the amendment 4, agent 6o Contents of amendment

Claims (1)

[Scope of Claims] 1. An enzyme capable of condensing saccharides is allowed to act on an aqueous glucose solution having a solid content concentration of 60% or more at 55°C or higher to produce branched oligosaccharides in the aqueous solution, and if necessary, further branched oligosaccharides are produced. A method for producing branched oligosaccharide syrup by a high-temperature condensation reaction characterized by separating and removing sugars other than sugar. 2. The method for producing a branched oligosaccharide syrup according to claim 1, which uses glucose containing 70% or more of glucose in the solid content. 3. The method for producing a branched oligosaccharide syrup according to claim 1 or 2, wherein the enzyme having the action of condensing sugars is glucoamylase derived from a microorganism of the genus Aspergillus. 4. The method for producing a branched oligosaccharide syrup according to claim 1 or 2, wherein the enzyme having the action of condensing sugars is glucoamylase derived from a microorganism of the genus Rhizopus.