JPH0517591A - Forming of gluten and formed gluten produced thereby - Google Patents

Abstract

PURPOSE:To obtain a formed gluten having softness by mixing wheat gluten with a substance capable of plasticizing the gluten and forming the mixture to a desired form. CONSTITUTION:The objective formed gluten is produced by compounding 100 pts.wt. of wheat gluten with 5-50 pts.wt. of a plasticizer (e.g. methanol, glycerol or silicone oil) and, as necessary, 2-60 pts.wt. of an agent for imparting water- resistance (e.g. liquid paraffin or octadecylethylene urea) and heating and forming the mixture to a desired form. In the case of using the plasticizer in combination with water, the total amount of the plasticizer and water is 40-50 pts.wt.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for molding wheat gluten into a desired shape and a molded product obtained by the method.

[0002]

2. Description of the Related Art Plastic moldings are widely known as moldings that are easy to process and inexpensive. Such a plastic molding is
It is incinerated after use or buried in the soil for disposal.

However, for such a processing method,
There are the following problems.

When a plastic molded body is incinerated, extremely high heat is generated, which may damage the incinerator or generate toxic gas.

Since the plastic molding is not decomposed by microorganisms in the soil, it remains as it is even if it is buried in the soil. Therefore, where there is little land,
There is a limit to disposal.

[0006] As described above, the plastic molded body causes a serious social problem regarding the processing method.

Therefore, the present inventors have found a molded product that can solve the above-mentioned problems, and have previously filed a patent application (see Japanese Patent Application Laid-Open No. 2-67109). This molded body is
It utilizes the thermosetting property of wheat gluten that is solidified by heat, and is obtained by putting hydrous wheat gluten in a mold and pressurizing it under heating to cure it.

The molded product thus obtained can be used as a substitute for plastic such as a container for storing articles. Moreover, since a natural product such as wheat gluten is used as a raw material, it can be easily decomposed by microorganisms in the soil after use only by burying it in the soil.

However, although the above-mentioned molded article has rigidity and is excellent in shape retention, its use is naturally limited due to poor plasticity and elasticity (hereinafter referred to as "flexibility"). . For example, it could not be used for items requiring flexibility, such as garbage bags often used at home.

An object of the present invention is to provide a method for obtaining a gluten molded product having flexibility and a gluten molded product obtained by the method.

[0011]

The method for forming gluten according to the first aspect of the invention is to mix wheat gluten with a substance capable of plasticizing wheat gluten, and heat the mixture to obtain a desired shape. It is a molding method.

It is preferable that a water resistance-imparting agent is added to the mixture.

The gluten molded article according to the third aspect of the present invention is obtained by heating a mixture of wheat gluten and a substance capable of plasticizing wheat gluten and molding the mixture into a desired shape.

It is preferable that a water resistance-imparting agent is added to the mixture.

Wheat gluten is a general term for proteins in wheat, and is a macromolecule in which gliadin and glutenin, which are polypeptides derived from wheat endoplasmic reticulum, cell membrane, and protein body, are bound to each other by disulfide bond or hydrogen bond. And usually 10 to 12% carbohydrates,
Contains 8-12% lipids. Wheat gluten can be used in the form of powder, granules or paste.

In the present application, the substance capable of plasticizing wheat gluten (hereinafter referred to as "plasticizer") is
Even when thermosetting wheat gluten that is thermosetting,
It refers to a substance that allows the resulting molded product to retain its flexibility. In other words, a compound having a high boiling point and compatibility with gluten is preferable.

Plasticizers are classified into hydrophilic plasticizers and hydrophobic plasticizers. The hydrophilic plasticizers used in the present invention include alcohols such as methanol, ethanol, propanol, butanol, pentanol; glycerin. , Ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, and other polyols; pentetol, hemositol, and other sugar alcohols. The hydrophilic plasticizers may be used alone or in combination of two or more kinds.

As the hydrophobic plasticizer, silicone oil,
Animal and vegetable oils and fats, liquid paraffin, hexane, petroleum ether, mineral oil and the like can be mentioned. When the hydrophobic plasticizer is used alone, the hydrophobic plasticizer and wheat gluten are separated. In order to avoid this, when using a hydrophobic plasticizer, it is preferable to use a hydrophilic plasticizer together.

The amount of the plasticizer used is not particularly limited, but 100 parts by weight of wheat gluten (hereinafter simply referred to as "part").
5 to 80 parts is preferable. When the amount of the plasticizer used is small, it is preferable to add a small amount of water in terms of molding. At this time, the total amount of plasticizer and water is 1 wheat gluten.
It is preferably 40 to 50 parts with respect to 00 parts. Moreover, the physical properties of the obtained molded article can be arbitrarily changed by adjusting the type and the amount of the plasticizer used.

A vulcanizing agent (crosslinking agent) such as sulfur may be mixed in the mixture of wheat gluten and the plasticizer. By mixing a vulcanizing agent, elasticity can be imparted to the obtained gluten molded body, and the tensile strength of the molded body is improved. this is,
It is presumed that this is because the vulcanizing agent reacts with the SH group or S—S bond of wheat gluten to form a partial crosslink in the molecule. Further, water resistance can be imparted to the obtained molded body.

Wheat gluten has a hydrophilic portion and a hydrophobic portion, and the hydrophobic portion is often buried inside the gluten molecule. Therefore, wheat gluten is also called globular protein. In this state, even if the vulcanizing agent is mixed in as described above, the SH group and the S—S bond in the hydrophobic portion have no chance to come into contact with the vulcanizing agent, and thus the crosslinking does not proceed. Therefore, it is necessary to expose the SH group and the S—S bond of the hydrophobic portion buried in the molecule so that they can be contacted with the vulcanizing agent. This is possible by adding protein denaturants such as urea, mercuric chloride, guanidine hydrochloride. If a protein denaturant is used together, crosslinking will be promoted. Further, the use of a protein denaturant tends to increase the elongation of the molded product.

The amounts of the vulcanizing agent and the protein denaturing agent are not particularly limited, but 20 parts or less of the vulcanizing agent and 50 parts or less of the protein denaturing agent are preferable to 100 parts of wheat gluten.

The term "water resistance-imparting agent" as used herein is used to impart water resistance to the finally obtained molded article, and is added to the mixture of wheat gluten and the plasticizer before molding. Is.

The water resistance-imparting agent is not particularly limited, and conventionally known commercial products can be used. Specific examples thereof include water repellent agents such as silicone oil and liquid paraffin;
Reactants (reactive water repellents) such as octadecyl ethylene urea and sodium lauryl sulfate can be used. Among them, it is preferable to use a compound having a group capable of binding to a protein (hereinafter referred to as “protein binding group”) such as octadecylethyleneurea. When a water resistance-imparting agent having a protein-bonding group is used, the water resistance-imparting agent exists in a state of being bonded to gluten in the obtained molded article, and therefore, in the solvent having the water resistance-imparting agent, Is preferable because it can prevent the elution of

The water resistance-imparting agent having a protein-binding group is
As described above, a conventionally known commercially available product can be used, but for example, an aliphatic group having 3 or more carbon atoms in which a protein binding group is introduced at the terminal or inside may be used.

The protein-binding group is not particularly limited as long as it shows a protein-binding property, and an aziridinyl group (see the following [Chemical formula 1]),

[0027]

[Chemical 1]

Examples thereof include epoxy group, isocyanate group, halogen group and the like.

When introducing the protein-binding group into the aliphatic group, the protein-binding group may be directly introduced into the aliphatic group, or may be bound to the protein-binding group and reactive with the aliphatic group. An active group and an unsaturated group represented by may be introduced by reacting with the aliphatic group.

When blending the water resistance-imparting agent, the blending amount is not particularly limited, but is preferably 2 to 60 parts with respect to 100 parts of wheat gluten. If the amount to be blended is less than 2 parts, sufficient water resistance cannot be expected, and if it exceeds 60 parts, there is a problem that strength is lowered.

As a method for imparting water resistance to the gluten molded body, in addition to the above, there are various methods such as applying a fluorine coating or a hydrophobic film to the molded product. According to the method of mixing the above-mentioned water resistance-imparting agent, the water resistance is imparted simply and inexpensively by mixing the water resistance-imparting agent in a mixture of wheat gluten and a plasticizer before molding. It is preferable because a gluten molded body can be obtained.

Next, an example of a method for producing a gluten compact will be described. First, a plasticizer is added to gluten powder, and the mixture is masticated so that both are uniform. The temperature during mastication is 30
The method of kneading with a roll at ˜35 ° C. is preferable. When a vulcanizing agent, a protein denaturing agent, etc. are added, it is preferable to masticate for a certain period of time and then add them for further mastication. In addition, particularly when urea is added as an aqueous solution, it is preferable to further dry at 40 ° C. for 24 hours after the addition.

Next, heat is applied to the masticated material to melt it, and it is molded into a desired shape. After cooling, the obtained gluten compact has flexibility. The heating temperature during molding is 1
20 ~ 160 ℃, the pressure at this time is 60 ~ 200k
It is g / cm ² . As a molding method, a press molding method,
A calendering method, an extrusion molding method, an injection method and the like can be mentioned. Moreover, the shape of the obtained molded body is not particularly limited, and examples thereof include those obtained by the above-described molding method, such as a sheet shape, a string shape, a bag shape, and a container shape.

[0034]

[Effect of the Invention] When the wheat gluten is mixed with the plasticizer and heat-molded as in the invention of claim 1, it is possible to obtain a flexible gluten molded body without the need of using a particularly complicated device or machine. it can.

According to the second aspect, a gluten molded article having excellent water resistance can be easily manufactured at low cost.

The gluten molding obtained by melting the mixture of wheat gluten and the plasticizer as in the third aspect of the invention has flexibility and is plastic such as a garbage bag or a storage bag for storing articles. It can be widely used as a substitute for. Further, after use, it is decomposed by microorganisms in the soil simply by burying it in the soil, so that it can be easily disposed of. Moreover, since no toxic gas is generated even when incinerated, the incineration is easy. Further, since wheat gluten is present as a natural protein in a large amount in the natural world and at a relatively low price, the molded product of the present application can be used in a wide range of applications.

According to the fourth aspect, it is possible to obtain a molded article having excellent water resistance, which is suitable for a wide range of applications.

[0038]

EXAMPLES Next, the present invention will be described in more detail by way of examples.

Examples 1 to 15 To 100 parts of wheat gluten powder (trade name: Fumerit E, manufactured by Nagata Sangyo Co., Ltd.), glycerin alone or a mixture of glycerin and water was added. The mixture of glycerin and water was adjusted so that the total amount was 40 parts. After uniformly mixing these with a mixer, roll kneading was performed at 30 to 35 ° C. for 5 minutes. Then, 0 to 9 parts of sulfur was added and kneaded for about 1 minute.

These are treated at 120 to 150 ° C. for 60 to 20
Press molding was performed under a pressure of 0 kg / cm ² for 3 minutes to obtain a translucent sheet molded body having a film thickness of 0.5 mm. Tests for tensile strength and tear strength were performed using test pieces obtained from these molded bodies.

[Table 1] shows the blending amounts of wheat gluten powder, glycerin, water and sulfur, and also shows the results of the above test.

The tensile strength test was carried out by pulling both ends of the produced dumbbell type test piece at a pulling speed of 200 mm / min using an Instron type universal testing machine.

The tear strength test was carried out by grasping both ends of the produced test piece with a gripper of a shopper and pulling.

As a comparative example, wheat gluten added with water alone was molded according to the above-mentioned method to obtain a film thickness of 0.
A 5 mm sheet-shaped molded product was obtained. The obtained molded body was hard and brittle.

[0045]

[Table 1]

As is clear from [Table 1], when sulfur is included, the tensile strength decreases as the glycerin concentration increases, regardless of whether or not sulfur is included. The gradient is 4.4 kg / deg in the system containing sulfur and 5.1 kg / de in the system not containing sulfur.
g, and the reduction of tensile strength can be suppressed by adding sulfur.

Regarding tear strength, glycerin 10 to 10
It can be seen that the value becomes high at 40 parts, and the tear strength remarkably decreases when it exceeds 40 parts. Further, when the system containing sulfur in the same amount was compared with the system containing sulfur, the system containing sulfur had a higher numerical value. Moreover, when compared with the systems containing sulfur, the higher the amount of sulfur added, the higher the value. As a result, it is possible to suppress the reduction in tear strength due to the addition of sulfur. This is because sulfur is partially crosslinked in the molecule of wheat gluten, which was also verified by the curast meter. The same can be said for the tensile strength.

Further, the molded body containing sulfur and the molded body not containing sulfur were immersed in water at 23 ° C. for 5 to 30 minutes, and the changes in strength over time during immersion in water were compared. From this, it was found that water resistance was imparted by adding sulfur.

Further, the molded articles of Examples 1 to 15 were buried in soil and observed for disintegration with time. As a result, most of them were found to have mold on the surface within 1 week, and after 4 weeks. The shape completely collapsed.

Examples 16 to 31 100 parts of wheat gluten powder (trade name: Fumerit E, manufactured by Nagata Sangyo Co., Ltd.), 30 parts of glycerin and 0 to 2 of water
After adding 0 parts and uniformly mixing with a mixer,
Roll kneading was carried out at 35 ° C. for 5 minutes. Then 0 urea
~ 36 parts and 0-3 parts of sulfur were added and kneaded for about 1 minute.

These are heated at 120 ° C. and the pressure is 60 to 150 kg.
/ M ² and press molding for 3 minutes, film thickness 0.5m
A semi-transparent sheet molding of m was obtained. Tests for tensile strength and tear strength were conducted using test pieces obtained from these molded products. The test method is Examples 1 to 15.
Is the same as.

[Table 2] shows the blending amounts of wheat gluten powder, glycerin, water, urea and sulfur, and also shows the results of the above test.

[0053]

[Table 2]

As is clear from [Table 2], as the urea concentration increases, both the tensile strength and the tear strength tend to decrease and the elongation at break tends to increase. However, for systems containing the same weight of urea, comparing the system containing sulfur and the system containing no sulfur, the system containing sulfur had a higher tensile strength and tear strength than the system containing no sulfur. It can be seen that the numbers are extremely high. This is because the SH group and SS bond of the hydrophobic portion of gluten buried inside the gluten molecule are exposed to the outside by the addition of urea, and the chance of contact with sulfur is increased to promote crosslinking. Is supposed to be.

Regarding the tear strength, when the system containing no water (Examples 16 and 17) and the system containing water (Examples 18 and 19) were compared, the numerical value of the system containing water was higher. . It is speculated that this is because water cooperates with the plasticizer glycerin. Even though water is removed by drying, the high tear strength value is due to the change in the intramolecular structure of gluten due to the addition of water and the formation of a new hydrogen bond. It is believed that there is.

Examples 32 to 43 To 100 parts of wheat gluten powder (trade name: Fumelli E, manufactured by Nagata Sangyo Co., Ltd.), either ethylene glycol or diethylene glycol was added, and water 0 to 0 was added.
Add 5 parts and mix evenly with a mixer to 30-35
Roll kneading was performed at 5 ° C for 5 minutes. Then sulfur 0-3
Parts were added and kneaded for about 1 minute.

These are heated at 120 ° C. and the pressure is 60 to 150 kg.
/ M ² and press molding for 3 minutes, film thickness 0.5m
A semi-transparent sheet molding of m was obtained. Tests for tensile strength and tear strength were performed using test pieces obtained from these molded bodies. The test method is the same as in Examples 1 to 15.

[Table 3] shows the blending amounts of wheat gluten powder, ethylene glycol or diethylene glycol, water and sulfur, and also shows the results of the above test.

[0059]

[Table 3]

As is apparent from [Table 3], regarding the tensile strength, when ethylene glycol is used, both of the cases where diethylene glycol is used are higher in numerical values in the system containing sulfur than in the system containing no sulfur. . In this case as well, it is presumed that partial cross-linking by sulfur is involved.

The tear strength is not affected by the presence or absence of sulfur,
3 ethylene glycol or diethylene glycol
It can be seen that the value is high in the range of 0 to 40 parts, and that the tear strength remarkably decreases when it exceeds 40 parts.

Examples 44 to 47 Wheat gluten powder (trade name: Fumerit E, manufactured by Nagata Sangyo Co., Ltd.) was mixed with diethylene glycol and octadecyl ethylene urea as a water resistance-imparting agent (trade name: Octex EM, Hodogaya Chemical Co., Ltd.). Made),
The mixture was uniformly mixed with a mixer, and roll kneading was performed at 30 to 35 ° C for 5 minutes. Then, sulfur was added and the mixture was kneaded for about 1 minute. (Table 4 below shows the respective blending amounts of wheat gluten powder, diethylene glycol, sulfur and octadecyl ethylene urea.).

[0063]

[Table 4]

Then, at 120 ° C., the pressure is 60 to 150 kg.
/ M ² and press molding for 3 minutes, film thickness 0.5m
A semi-transparent sheet molding of m was obtained. The water resistance test shown below was performed using the test piece obtained from this molded body.

Water Resistance Test Each test piece was immersed in water, and then a tensile test (test method is the same as in Examples 1 to 15) was performed on each test piece.

FIG. 1 shows the relationship between the tensile strength obtained by the tensile test and the immersion time in water.

As is apparent from the graph of FIG. 1, when comparing the system containing octadecylethyleneurea with the system not containing octadecylethyleneurea, the system containing octadecylethyleneurea was
Has high tensile strength. That is, the one containing octadecyl ethylene urea has excellent water resistance.

Further, when compared in the same composition containing octadecylethyleneurea, 15 parts (Example 47) had better water resistance than 8 parts (Example 46) mixed with 100 parts of wheat gluten. Showing sex.

Further, a molded article containing octadecylethyleneurea (Examples 46 and 47) was embedded in the soil, and the temporal disintegration property was observed. As a result, almost all the molds were found to have mold on the surface within 1 week, and the shape completely collapsed within 4 weeks. As described above, the biodegradability was not significantly different from that of the molded product containing no octadecylethyleneurea.

As another embodiment, wheat gluten 1
10 to 20 parts of silicon oil was added to a mixture of 00 parts and 30 parts of diethylene glycol to obtain a sheet-shaped molded body. With respect to this molded body, the change in strength over time when immersed in water was measured. As a result, it was found that the water resistance was significantly improved.

Example 48 30 parts of diethylene glycol was added to 100 parts of wheat gluten powder (trade name: Fumerit E, manufactured by Nagata Sangyo Co., Ltd.), and octadecyl ethylene urea (trade name: Octex EM, Hodogaya) was added as a water resistance-imparting agent. Kagaku Co., Ltd.) was added while changing the compounding amount, and the mixture was uniformly mixed with a mixer and roll kneading was performed at 30 to 35 ° C. for 5 minutes.

Then, at 120 ° C., the pressure is 60 to 150 kg.
/ M ² and press molding for 3 minutes, film thickness 0.5m
A semi-transparent sheet molding of m was obtained. Using a test piece obtained from this molded product, an elution test of octadecyl ethylene urea was conducted. Toluene was used as the solvent.

The amount of octadecyl ethylene urea blended,
The relationship with the amount of octadecyl ethylene urea eluted with toluene is shown in FIG.

As is clear from FIG. 2, in any case, there is a constant error (error of about 2% by weight) between the blending amount and the elution amount. That is, about 2% by weight of octadecyl ethylene urea was not eluted in toluene. It can be inferred that about 2% by weight of octadecylethyleneurea did not elute because it bound to gluten.

That is, by adjusting the blending amount of the water resistance-imparting agent, it is possible to obtain a gluten molded product in which elution into the solvent cannot occur.

[Brief description of drawings]

FIG. 1 is a graph showing a relationship between immersion time in water and tensile strength in a water resistance test of Examples 44 to 47.

FIG. 2 is a graph showing the relationship between the blending amount of octadecylethyleneurea and the amount of octadecylethyleneurea eluted with toluene in the dissolution test of Example 48.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takashi Dozen             Nagata, 215 Senbonya, Yamazaki-cho, Shiawawa-gun, Hyogo Prefecture             Sangyo Co., Ltd. (72) Inventor Masakazu Sugimoto             Nagata, 215 Senbonya, Yamazaki-cho, Shiawawa-gun, Hyogo Prefecture             Sangyo Co., Ltd. (72) Inventor Mitsuo Yasui             15-16 Shibukawa, Terado-cho, Hyuga City, Kyoto Prefecture (72) Inventor Yamashita Iwao             1-22-14 Yuyamadai, Kawanishi City, Hyogo Prefecture

Claims (4)

[Claims] 1. A method for molding gluten, which comprises mixing wheat gluten with a substance capable of plasticizing wheat gluten and heating the mixture to form a desired shape. 2. The method for molding gluten according to claim 1, wherein a water resistance-imparting agent is added to the mixture. 3. A gluten compact, which is obtained by heating a mixture of wheat gluten and a substance capable of plasticizing wheat gluten and shaping the mixture into a desired shape. 4. The gluten molded article according to claim 3, wherein the mixture is blended with a water resistance-imparting agent.