JP2004024234A - Method for producing xylo-oligosaccharide - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing xylo-oligosaccharide useful as a sweetening material by using conventionally wasted corn cob meal as a raw material. <P>SOLUTION: This method for producing the xylo-oligosaccharide is provided by steaming the corn cob meal in a closed and pressurized continuous extruders having a plurality of steps, and then adding xylanase into the filtrate obtained by removing solid materials by a filtering device for its hydrolysis treatment. The steaming conditions in each of the plurality of steps of the continuous extruders are set to elevate the temperature and pressure by going from a first extruder to the final extruder and also the conditions of the final extruder are 150-250°C and 20-29 MPa. <P>COPYRIGHT: (C)2004,JPO

Description

【００２４】
前記蒸煮したコーンコブミールを濾過装置にて濾過することにより得られた濾液を、攪拌装置を備えた保温機構を有する反応容器内に投入し、更に濾液１００質量部に対して、キシラナーゼ３質量部、水酸化ナトリウム０．１質量部を前記反応容器内に投入した後、温度４５℃、攪拌速度毎分１５０回転で２４時間反応させ、キシロオリゴ糖を得た。
【００２５】
【発明の効果】
本発明により、従来廃棄されていたコーンコブミールを原料とする、甘味料として有用なキシロオリゴ糖の製造方法を提供することができる。
【図面の簡単な説明】
【図１】本発明における蒸煮処理を行う圧力容器の一例であるシリンダー内が圧力密閉されている押出機の部分断面図である。
【符号の説明】
１　シリンダー
２　材料投入口
３　スクリュー
４　螺旋状のフライト
５　ヒーター
６　駆動手段
７　モーター
８　減速ギア
９　原動歯車
１０　従動歯車
１１　取出口
１２　断熱保温材
１３　温度センサー
１４　圧力センサー[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for producing a xylo-oligosaccharide useful as a sweetener using corn cob meal as a raw material.
[0002]
[Prior art]
Xylooligosaccharide is a lactic acid bacterium drink certified as a food for specified health use having the function of keeping the stomach in good condition through the selective growth promoting effect of intestinal bacteria, a useful saccharide used for chocolate and the like, medicine, In the field of sanitary products, it is used as an emulsifier and a moisturizing ingredient for the skin. It is also used not only for human food but also as an additive for livestock feed.
[0003]
In general, oligosaccharides used for specific health foods, most of which have an intestinal action, that is, reduce the number of bacteria of the genus Escherichia coli, which is "intestinal bad bacteria", and the genus Clostridium, which is an intestinal putrefactive fermentative bacterium. It has the effect of increasing bifidobacteria, which is called "good intestinal bacteria". For example, wheat bran is a polysaccharide composed of hemicellulose having xylan as a main chain, and is added to food as a food having an intestinal action as a hardly decomposable plant fiber.
[0004]
Xylose, which is a raw material of xylooligosaccharide, is contained in wood in a large amount, and xylan in such wood is extracted to produce xylooligosaccharide.
In addition, a method for producing xylo-oligosaccharides has been proposed for producing xylo-oligosaccharides from a reaction filtrate obtained from a pulp hemicellulase treatment step (for example, see Patent Document 1).
[0005]
On the other hand, corn cob meal obtained by drying and crushing corn cob is used as a fungal bed for mushroom cultivation, abrasives for beans or nesting material for animals, etc., but it is extremely rarely used as an industrial raw material. It is discarded as waste, and its disposal method is mainly incineration, so there are many problems such as deteriorating the environment. Effective use of corn cob is also being studied.
[0006]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2000-333892
[Problems to be solved by the invention]
Accordingly, the present invention has been made in order to solve the above problems, and has as its object to provide a method for producing xylo-oligosaccharides useful as sweeteners, using corn cob meal that has been conventionally discarded as a raw material. .
[0008]
[Means for Solving the Problems]
The object has been achieved by the present invention described below.
That is, the present invention
A method for producing xylo-oligosaccharides, comprising steaming corn cob meal in a pressure vessel at 150 to 250 ° C. and 20 to 29 MPa, adding xylanase to a filtrate from which solid matter has been removed by a filtration device, and subjecting the filtrate to hydrolysis treatment. It is.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
In the method for producing a xylo-oligosaccharide of the present invention, first, corn cob meal is steamed in a pressure vessel at 150 to 250 ° C. and 20 to 29 MPa (hereinafter sometimes referred to as “steaming treatment”).
[0010]
The steaming process in the present invention will be described.
In the steaming treatment in the present invention, water is added to corn cob meal (dried and crushed and powdered corn cob), and is placed in a subcritical (one step before supercritical) 150-250 ° C. and 20-29 MPa pressure vessel. Refers to the process of steaming.
[0011]
In the steaming treatment, it is necessary to set the temperature to 150 to 250 ° C. and the pressure to 20 to 29 MPa, and it is preferable to set the temperature to 180 to 200 ° C. and the pressure to 25 to 28 MPa.
The amount of water to be added is preferably from 10 to 1,000 parts by mass, more preferably from 50 to 100 parts by mass, based on 100 parts by mass of corn cob meal.
The steaming treatment is preferably performed for 10 to 30 minutes, and more preferably for 15 to 20 minutes.
[0012]
Further, in the steaming treatment, a sulfite compound can be added to corn cob meal together with water. By adding the sulfite compound to corn cob meal, the cooking time can be shortened. Examples of the sulfite compound include sodium sulfite and calcium sulfite.
Further, the addition amount of the sulfite compound is preferably 1 to 10 parts by mass, more preferably 2 to 5 parts by mass, based on 100 parts by mass of corn cob meal.
[0013]
The steaming process is suitably performed by an extruder shown in FIG. FIG. 1 is a partial cross-sectional view of an extruder in which the inside of a cylinder is pressure-sealed, which is an example of a pressure vessel for performing a steaming process in the present invention. The extruder kneads (steams) corn cob meal and water (hereinafter, may be simply referred to as “material”) supplied from the cylinder 1 having the material input port 2 at the base, and the corn cob meal supplied from the material input port 2 to the front end side. Screw 3 having a helical flight 4 for extruding the same, a heater 5 for heating the cylinder 1, a motor 7, a driving gear 9, and a driven gear 10 connected to a power supply (not shown) for rotating the screw 3. , A driving means 6 such as a reduction gear 8 having an outlet, an outlet 11 for taking out the steamed and extruded product, an insulating heat insulating material 12 covering the cylinder 1 and the heater 5, and the like. In addition, a pump (not shown) is attached to the material inlet 2, and the material is fed into the cylinder 1 through the material inlet 2 from the pump. Further, the pitch of the spiral flight 4 of the screw 3 becomes shorter as approaching the outlet 11. Further, a temperature sensor 13 and a pressure sensor 14 are provided near the tip of the screw 3 of the cylinder 1.
[0014]
The steaming treatment by the extruder shown in FIG. 1 is performed in the following procedure. A material is introduced into the cylinder 1 through a material introduction port 2 from a pump (not shown), and the temperature in the cylinder 1 is adjusted to a target temperature by a heater 5. Further, by rotating the rotation shaft of the motor 7 clockwise as viewed from the motor 7 side, the driving gear 9 is rotated clockwise, the driven gear 10 is rotated counterclockwise, and the screw 3 is further rotated counterclockwise. The corn cob meal is extruded in the direction of the outlet 11 while being steamed. Since the pitch of the spiral flight 4 of the screw 3 becomes shorter as it approaches the outlet 11, the corn cob meal is compressed as it approaches the outlet 11, and a predetermined pressure is applied. The corn cob meal after the steaming process is extruded from the outlet 11.
In the present embodiment, the temperature sensor 13 and the pressure sensor 14 are disposed near the tip of the screw 3 of the cylinder 1, but the temperature sensor 13 is disposed at the position of the tip of the screw 3 from the axial center of the cylinder 1. The position of the pressure sensor 14 may be a space of 1/4 of the screw 3 of the cylinder 1 on the tip side.
[0015]
When performing the steaming process by the extruder shown in FIG. 1, the temperature and pressure measured by the temperature sensor 13 and the pressure sensor 14 need to satisfy the conditions of 150 to 250 ° C. and pressure: 20 to 29 MPa.
[0016]
Further, a method of performing a steaming treatment by connecting two or more extruders shown in FIG. 1 in series, that is, directly mixing a mixture of corn cob meal and water steamed in the first extruder and extruded from the outlet 11 into the second extruder The method of feeding the mixture into the material input port 2 of the extruder and further steaming is also suitably performed.
When two or more extruders shown in FIG. 1 are connected in series to perform a steaming treatment, the steaming conditions of each extruder are as follows: the steaming condition of the last connected extruder is temperature: 150 to 250 ° C., pressure: 20 to As long as the condition of 29 MPa is satisfied, they may be the same or different. When the steaming conditions of each extruder are different, it is preferable that the temperature and the pressure rise as the process proceeds from the first extruder to the last connected extruder.
[0017]
By the above-mentioned steaming of corn cob meal, polyphenol (produced by changing from lignin) and cellulose produced by decomposing lignocellulose and soluble hemisemirose (hereinafter referred to as “soluble xylan”) are obtained. Is filtered by a filtration device (filtration treatment) to obtain a mixed solution of polyphenol and soluble xylan as a filtrate.
[0018]
The soluble xylan obtained by the filtration treatment becomes a xylo-oligosaccharide by performing a hydrolysis treatment (enzyme treatment) with xylanase.
The enzymatic treatment can be performed in the following procedure. In a reaction vessel equipped with a stirrer and having a heat retaining mechanism, xylanase is added to the filtrate from which solids have been removed by a filtration device to cause a reaction, and suspended substances are removed from the obtained reaction product by a filtration device and dried. .
Xylooligosaccharide is obtained by the above procedure.
[0019]
The amount of xylanase added in the enzyme treatment is preferably 0.1 to 5 parts by mass, more preferably 0.5 to 2 parts by mass, per 100 parts by mass of the filtrate.
Further, the enzyme treatment is preferably performed under conditions of pH 3 to 8, and more preferably under conditions of pH 4 to 6.
Further, the treatment temperature is preferably from 30 to 50C, more preferably from 40 to 45C. The stirring speed is preferably from 60 to 200 rotations per minute, more preferably from 100 to 150 rotations. The processing time is preferably 15 to 30 hours, more preferably 20 to 24 hours.
[0020]
Xylooligosaccharides are used in various foods because they have the effect of preventing tooth decay and improving the balance of intestinal bacteria to promote health, and demand is expected to increase significantly in the future.
[0021]
【Example】
Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited thereto.
(Example 1)
Steaming of corn cob meal was carried out using a series of four extruders similar to the pressure-sealed extruder shown in FIG. The four extruders connected in series are connected to the outlet 11 of the first extruder and the material inlet 2 of the second extruder, and similarly connected to the fourth extruder. The kneaded product steamed by one extruder is directly charged into the cylinder 1 through the material input port 2 of the second extruder, and similarly reaches the material input port 2 of the fourth extruder.
[0022]
5 parts by mass of calcium sulfite and 50 parts by mass of water were added to 100 parts by mass of corn cob meal, and the mixture was introduced into the cylinder 1 from the material introduction port 2 of the extruder sealed as shown in FIG. Next, the temperature and pressure of the first extruder are set to the values shown in Table 1, the motor is driven, the screw 3 is rotated to knead (steam) for 5 minutes, and then extruded from the outlet 11. The kneaded product extruded from the outlet 11 was directly charged into the cylinder 1 through the material input port 2 of the second extruder, and was similarly kneaded (steamed) to the fourth extruder. Table 1 shows the setting conditions and kneading (steaming) time of each extruder. The temperatures and pressures shown in Table 1 are values measured by the temperature sensor 13 and the pressure sensor 14.
[0023]
[Table 1]

[0024]
The filtrate obtained by filtering the steamed corn cob meal with a filtration device is charged into a reaction vessel having a heat retaining mechanism equipped with a stirrer, and further, with respect to 100 parts by mass of the filtrate, 3 parts by mass of xylanase, After 0.1 parts by mass of sodium hydroxide was charged into the reaction vessel, the reaction was carried out at a temperature of 45 ° C. and a stirring speed of 150 revolutions per minute for 24 hours to obtain a xylo-oligosaccharide.
[0025]
【The invention's effect】
According to the present invention, it is possible to provide a method for producing a xylo-oligosaccharide useful as a sweetener using corn cob meal that has been conventionally discarded as a raw material.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional view of an extruder as an example of a pressure vessel for performing a steaming process in the present invention, in which a cylinder is pressure-sealed.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cylinder 2 Material input port 3 Screw 4 Spiral flight 5 Heater 6 Driving means 7 Motor 8 Reduction gear 9 Driving gear 10 Follower gear 11 Outlet 12 Heat insulation material 13 Temperature sensor 14 Pressure sensor

Claims (1)

A method for producing xylo-oligosaccharides, comprising steaming corn cob meal in a pressure vessel at 150 to 250 ° C. and 20 to 29 MPa, adding xylanase to a filtrate from which solids have been removed by a filtration device, and subjecting the filtrate to hydrolysis treatment. .

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