JPH119202A - Production of allergen-reduced rice and processed food by using allergen-reduced rice - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing the subject rice, by which a protein, especially an albumin fraction is removed therefrom in high removing proportion by allowing a salt solution within the specific range of the temperature and a specific proteolytic enzyme to act on the raw material rice. SOLUTION: A raw material rice is dipped in 40-60 deg.C salt solution, and the salt-soluble-protein in the raw material rice is extracted. The salt solution is separated from the processing rice and the rice is washed. The objective allergen-reduced rice is obtained by allowing a lactic bacteria-derived protease or an aspartyl proteinase to act on the washed processing rice in the method for producing the objective allergen-reduced rice. A Japonica rice is preferable as the raw material rice, and the rice polished so as to have 80-95% refined degree is preferably used. An inorganic salt such as a hydrochloride and an alkali metal salt such as a sodium salt, especially, sodium chloride is preferably used as the salt for the extraction by an aqueous salt solution. The amount of the proteolytic enzyme acting on the processing rice is preferably 0.01-5 pts.wt. based on 100 pts.wt. treating rice.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing allergen-reduced rice, and more particularly to a method for producing allergen-reduced rice capable of efficiently removing allergen from raw rice. The present invention also relates to a processed food using allergen-reduced rice.

[0002]

In recent years, food allergy sufferers are rapidly increasing with changes in living environment such as eating habits and lifestyle. As one of these treatments, alternative diets with other non-allergenic similar foods have been attempted to limit the intake of foods that cause allergic reactions. One example is the rapid increase in allergy to rice, and rice allergy sufferers generally use rice instead of rice.
There is a problem that the taste is compensated for by means of barbs, canes and the like, and it is not possible to obtain a satisfactory taste.

On the other hand, studies on allergens causing such food allergies have been advanced, and in the case of rice, it is clear that a lot of allergens are present in the globulin fraction and albumin fraction which are salt-soluble fractions, especially in the albumin fraction. [Miki Matsuda et al., Agric. Bio
l. Chem 52 (6) 1465-1470 (198
8); Miki Matsuda et al., Agric. Biol. Chem5
5 (2) 509-513 (1991)]. It has also been confirmed that salt-insoluble components include salt-insoluble allergens that respond to 20 to 30% of rice allergic patients [for example, Yoshio Ikezawa et al., Annual Report of the Japan Lidiaoli Association, 13, 41. -60 (1990)].

[0004] For this reason, it has been studied to mainly remove salt-soluble fractions that cause allergens from rice and the like.
Japanese Patent Publication No. 6-9472 discloses that a protease is allowed to act on a cereal material containing starch as a main component, and the solubility of the salt-soluble protein in the cereal is increased to 80% or more by 10% trichloroacetic acid solubility. A cereal in which allergens are reduced by hydrolyzing proteins in the cereal and removing soluble components is disclosed. However, this cereal is very expensive due to its special production method, and is not suitable for allergy sufferers to use it as a daily staple food.

[0005] JP-A-6-253758 discloses a method for producing a cereal preparation with reduced allergen by allowing collagenase to act on cereals such as rice. This publication describes that salt water can be acted on before or after the action of collagenase on cereals. However, in this method, cereals such as rice must be in the form of powder or paste, so that it is difficult to reduce allergens in the state of rice grains.

The present invention has been made on the basis of the above-mentioned object, and it is an object of the present invention to efficiently and at a high removal rate an albumin fraction, which is a major component of allergen in rice, from proteins in raw rice. An object of the present invention is to provide a method for producing possible allergen-reduced rice. Further, it is possible to provide a method for producing an allergen-reduced rice that can efficiently remove an albumin fraction from rice grains at a high removal rate, maintain the shape of rice grains after treatment, and is suitable for making rice. With the goal. Further, another object of the present invention is to provide a processed food using the allergen-reduced rice obtained by processing the obtained allergen-reduced rice.

[0007]

Means for Solving the Problems In view of the above-mentioned problems, as a result of intensive studies, the present inventors have found that the efficiency of removing salt-soluble proteins varies greatly depending on the temperature of the salt aqueous solution, and that the salt aqueous solution in a predetermined temperature range is not soluble in salt. It has been found that proteins, especially albumin fractions, have excellent extractability, and if a salt solution in this temperature range and a lactic acid bacterium-derived proteinase or aspartic proteinase are selected and acted as a proteolytic enzyme, the protein in the raw rice can be obtained. In particular, it has been found that the albumin fraction can be removed at a high removal rate. In addition, the present inventors describe the procedure of the action of the salt aqueous solution and the protease as follows. First, after extracting the salt-soluble protein in the raw rice with a salt aqueous solution in a predetermined temperature range, the salt-soluble protein is retained by the predetermined protease. By decomposing and removing the protein, it is possible to efficiently remove the protein, and the resulting allergen-reduced rice maintains the shape of the rice grain firmly and is suitable for rice cooking. Was. The present invention has been made based on these.

[0008] That is, in the method for producing allergen-reduced rice according to claim 1 of the present invention, the raw rice is immersed in an aqueous salt solution at 40 to 60 ° C, and the salt-soluble protein in the raw rice is extracted. Activated proteinase or aspartic proteinase.

[0009] Therefore, allergen proteins in rice can be removed efficiently and at a high removal rate. The reason why such an effect can be obtained is that the raw rice is first prepared in the range of 40 to 6
The salt-soluble allergen is extracted and removed by immersion in a relatively high-temperature salt aqueous solution at 0 ° C., and further, a specific protease is allowed to act thereon to decompose and remove the remaining salt-soluble and salt-insoluble proteins, which are allergens. Because it is. Moreover, in the method of the present invention, since the step of decomposing with the protease is provided after the extraction of the salt aqueous solution, the salt contained in the raw rice is diluted by the proteolysis step, and the water content in the allergen-reduced rice is reduced. Since the rate is high, the shape of rice grains is well maintained.

In the processed food using the allergen-reduced rice according to claim 2 of the present invention, the raw rice is immersed in an aqueous salt solution at 40 to 60 ° C. to extract the salt-soluble protein in the raw rice. Of lactobacillus-derived proteinase or aspartic proteinase to produce allergen-reduced rice. Therefore, it can be used for cooked rice, packaged food, dried rice, porridge, dango, rice cake, pilaf, noodles, and the like.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. In the present invention, there is no particular limitation on the raw rice to be reduced in allergens, and any rice such as japonica rice and indica rice can be used. Japonica rice is preferred in view of the dietary habits of Japanese people. Also, this raw rice is
It is preferable to use one that has been whitened to 80 to 95%, particularly 85 to 90%.

[0012] Further, as the salt used for the extraction of the aqueous salt solution,
Inorganic salts such as hydrochloride, sulfate, carbonate or phosphate can be used. On the other hand, alkali metal salts such as sodium salt and potassium salt can be used. Particularly, sodium chloride (salt) is preferable.

Among the various proteases, the endo-type aspartic proteinase (manufactured by Amano Pharmaceutical Co., Ltd., manufactured by Amano Pharmaceutical Co., Ltd.) And a lactic acid bacterium-derived (Lactobacillus casei) proteinase. By using these proteolytic enzymes, it is possible to sufficiently decompose the albumin fraction that becomes an allergen, while suppressing the degradation of proteins that do not become an allergen as much as possible.

Next, a method for producing the allergen-reduced rice of the present invention, in which the raw rice is treated with the salt and the protease described above, will be described. First, in the present invention, the raw rice is immersed in a salt solution (salt solution extraction step). At this time, an aqueous solution having a temperature range of 40 to 60 ° C. is used as the salt aqueous solution. This is because the temperature of the salt aqueous solution is 4
If the temperature is lower than 0 ° C., the removal rate of the salt-soluble protein, especially the albumin fraction is not sufficient, while if it is higher than 60 ° C., starch flows out of the raw rice and the rice grains become small. Further, the concentration of the salt aqueous solution is preferably 0.05 to 5 molar. The concentration of the salt aqueous solution is less than 0.05 molar,
Alternatively, when the concentration exceeds 5 molar, the outflow of the salt-soluble protein as an allergen is not sufficient, and when the concentration of the salt aqueous solution exceeds 5 molar, the obtained allergen-reduced rice tends to become brittle. In particular, the concentration of the salt aqueous solution is set to 0.5 to 2
By setting the molar concentration, the salt-soluble protein can be more favorably extracted. The amount of the salt aqueous solution as described above is not particularly limited as long as the raw rice is completely immersed. For example, 1.5 times the amount of the raw rice may be used.

[0015] The time required for the salt aqueous solution extraction step may be appropriately set according to the concentration and temperature of the salt aqueous solution, and is usually about 12 to 36 hours, for example, about 24 hours.

When the salt aqueous solution extraction step is completed in this way, the salt aqueous solution and the treated rice are separated and washed, and then the treated rice is treated with a lactic acid bacterium-derived proteinase or aspartic proteinase (hereinafter simply referred to as "specific protein degradation"). (Called an enzyme) (enzymatic decomposition step). In this case, the amount of the specific protease is preferably 0.01 to 5 parts by weight based on 100 parts by weight of the treated rice. If the amount of the specific protease is less than 0.01 part by weight, the protein as an allergen is not sufficiently degraded, while if it exceeds 5 parts by weight, rice grains are brittle and easily broken. In particular, the amount is preferably 0.05 to 0.2 parts by weight based on 100 parts by weight of the treated rice.
Such a specific proteolytic enzyme has an amount of 10 to 10
If necessary, a surfactant, an organic acid such as citric acid as a pH adjuster, etc. are added to about twice the amount of water, and the temperature is within the activation temperature range of the specific protease, for example, from room temperature to 55 ° C.
The fermentation treatment is performed within the temperature range described above and under pH conditions. The enzymatic treatment step may be performed for a time sufficient to decompose proteins not extracted in the above-described salt aqueous solution extraction step, and is usually performed for about 12 to 36 hours, for example, about 24 hours.

In the method for producing allergen-reduced rice of the present invention as described above, the protein as an allergen can be sufficiently removed even if granular rice is used as the raw rice instead of crushed rice. In particular, in the case of albumin, about 1/32 or less of the raw rice (ELISA inhibition test (ELISA
-Inhibition). Moreover, the allergen-reduced rice thus obtained has a low degree of embrittlement with respect to the raw rice, so that it can maintain rice graininess and is suitable for steaming or the like to produce cooked rice.

Next, a processed food using the allergen-reduced rice of the present invention will be described. Processed food using the allergen-reduced rice of the present invention is obtained by processing the allergen-reduced rice obtained as described above. It may be immersed, put into a container such as a retort pouch or a plastic molded container, sealed, and then sterilized. Further, the allergen-reduced rice is boiled in a porridge, α-amylase is added to the rice, and the resulting liquid is liquefied. If necessary, fruit juice, milk, and the like are added to the liquefied product, thereby comprising the allergen-reduced rice. It can be a drink.

Further, the allergen-reduced rice obtained by the method of the present invention can be used for various foods in which other ordinary rice is used, such as dango, rice cake, pilaf and noodles. Can be.

Although the present invention has been described in detail above, the present invention is not limited to the above description, and various applications are possible without departing from the spirit of the present invention. For example, although the method of the present invention can remove allergens satisfactorily from raw rice in the form of rice granules, the method does not need to be in the form of rice granules. May be applied. Further, the concentration of the protease, the concentration of the salts, the treatment time, and the like can be appropriately set according to the desired removal rate of the allergen substance such as albumin.

[0021]

The present invention will be described in more detail with reference to the following specific examples. Test Example 1 Confirmation of albumin extraction effect by temperature of salt aqueous solution 1M (molar concentration) per 1 kg of commercially available Koshihikari as raw material rice
Add 1.5 liters of sodium chloride solution each, suspend until the whole becomes homogeneous, 5, 25, 50 and 60 ° C
The salt extraction was performed for 24 hours in each of the thermostats. After extraction,
The sodium chloride solution was separated from the treated rice, and the treated rice was washed in running water for 1 hour. The treated rice was immediately freeze-dried and pulverized. The absorbance at 490 nm of the treated rice thus pulverized was measured by an ELISA test.

The ELISA test was performed as follows. 10 ml of PB per 1 g of crushed treated rice sample
S (prepared to pH 7.4 with a 20 mM phosphate buffer containing 150 mM sodium chloride) was added, the mixture was allowed to stand at 4 ° C. for 3 hours, sonicated for 10 minutes, and then centrifuged (10000 rpm) for 10 minutes. Then, the supernatant (extract) was separated.

On the other hand, a rice albumin fraction was added to an ELISA plate so that the amount of rice albumin was 1 μg. 4
The plate was allowed to stand overnight at 0 ° C. to bind to the plate. The plate was washed three times with a PBS-T solution (prepared to pH 7.4 with a 20 mM phosphate buffer containing 150 mM sodium chloride and 0.05% Tween-20), and washed with 3% B
After blocking with an SA (bovine serum albumin) -PBS solution and allowing to stand for 2 hours, the plate was washed with PBS-T solution for 4 hours.
Washed twice.

Then, 50 μl of the extract diluted 4 times
And 50 μl of a 300,000-fold diluted anti-rice albumin monoclonal antibody (25B9), and allowed to stand at 4 ° C. overnight. This reaction solution was added to the plate, and after standing for 2 hours, the plate was washed five times with a PBS-T solution. Subsequently, a 10,000-fold diluted peroxidase-conjugated anti-mouse Ig
The G antibody was added, and after standing for 2 hours, the plate was washed six times with a PBS-T solution. Substrate solution (orthophenylenediamine 4mg
Phosphoric acid containing H ₂ O ₂ 0.015% - added citrate buffer at that prepared in pH 5.0), the reaction was stopped by addition of 2N sulfuric acid after 30 minutes. 49 of this reaction solution
The absorbance at 0 nm was measured with an ELISA reader. Also,
The absorbance at 490 nm was similarly measured with an ELISA reader for the extracts diluted 8, 16, 32 and 64 times. For comparison, the raw rice was subjected to an ELISA test at 490 nm in the same manner as the treated rice described above.
Was measured for absorbance. These results are shown in FIG.

As is clear from FIG. 1, the treated rice extracted with the salt aqueous solution showed an increase in absorbance at 490 nm as compared with the raw rice, and a decrease in antigenicity was observed. This tendency was greater as the temperature of the salt aqueous solution was improved. Particularly, in the salt aqueous solutions at 50 ° C. and 60 ° C., the antigenicity was reduced to 1/8 or less of that of the raw rice. In addition, although a decrease in antigenicity was observed in a 60 ° C. salt aqueous solution, starch flowed out and rice grains were thin and small, and the extraction temperature with a salt aqueous solution was limited to 60 ° C. Test Example 2 Confirmation of Albumin Degrading Effect by Kind of Enzyme To 1 kg of commercially available rice Koshihikari, actinase,
An enzyme aqueous solution obtained by dispersing 1.5 g of metalloproteinase, aspartic proteinase and lactic acid bacteria-derived proteinase in 1.5 liters of water was added, and suspended until the whole became homogeneous. An enzymatic reaction was performed. Then, the treated rice after the reaction was immediately freeze-dried and pulverized.

Using the milled rice thus treated as a sample, the antigenicity of the rice against the albumin fraction, which is a major allergen of rice, was determined by an ELISA test using a rice albumin monoclonal antibody in the same manner as in Test Example 1 described above.
The absorbance at 0 nm was measured. For comparison, the absorbance at 490 nm was similarly measured for the raw rice by the ELISA test. These results are shown in FIG. In addition, about the aspartic proteinase, the absorbance at 490 nm in the extract diluted 2 times was also measured.

As is clear from FIG. 2, the treated rice treated with the enzyme showed an increase in absorbance at 490 nm as compared with the raw rice, and a decrease in antigenicity was observed. This tendency was particularly large in aspartic proteinases and lactic acid bacteria-derived proteinases, and the antigenicity was reduced to one-eighth or less of the raw rice. Watanabe et al.'S method (J. Food. Sci.
ence 55 (3) 781-783 (1990)).
When the solubility of 0% trichloroacetic acid was examined, it was found that each was 7%.
2% and 69%. Example 1 To 1 kg of commercially available rice Koshihikari was added 1.5 liters of a 1 M sodium chloride solution at 50 ° C, suspended until the whole became uniform, and subjected to salt extraction in a 50 ° C constant temperature bath for 24 hours. After the extraction, the sodium chloride solution and the rice (salt extracted rice) were separated, and the salt-treated rice was washed in running water for 1 hour. 1.5 g of aspartic proteinase was added to the salt-extracted rice.
An enzyme aqueous solution dispersed in 5 liters of water is added, and the whole is suspended until it becomes uniform.
An enzymatic reaction was performed for hours to produce rice with reduced allergens. Test Example 3 Ground Allergen Reduced Rice 1
g in the same manner as in Test Example 1 described above, using a rice albumin monoclonal antibody to determine the antigenicity against the albumin fraction, which is a major rice allergen, using a stock solution, 2 fold, 4 fold, and 1 fold.
The absorbance at 490 nm was measured in the extract diluted 6 times, 32 times and 64 times by the ELISA test. Further, for comparison, the absorbance at 490 nm was measured by an ELISA inhibitor test in an extract diluted 4 times, 16 times, 32 times and 64 times with respect to the raw rice. These results are shown in FIG.

As is clear from FIG. 3, the allergen-reduced rice treated by the method of the present invention is 49 times less than the raw rice.
Significant improvement in absorbance at 0 nm was observed, and it was confirmed that the antigenicity was reduced to 1/32 or less of the raw rice. Test Example 4 The allergen-reduced rice obtained in Example 1 was cooked and fed as a staple food to six rice allergic patients, and the state of improvement of atopic dermatitis was observed. Table 1 shows the results.

[0029]

[Table 1]

As is clear from Table 1, all patients reduced the atopic dermatitis by the allergen-reduced rice of Example 1, and allergen-causing protein in the rice was removed by the method of the present invention. You can see that it is done. Example 2 1.5 kg of a 1 M sodium chloride solution at 50 ° C was added to 1 kg of commercially available Koshihikari as raw rice, suspended until the whole became homogeneous, and subjected to salt extraction in a 50 ° C constant temperature bath for 24 hours. After the extraction, the sodium chloride solution was separated from the rice (salt-treated), and the salt-treated rice was washed in running water for 1 hour. To this salt-treated rice was added an aqueous enzyme solution obtained by dispersing 1.5 g of lactic acid bacteria-derived proteinase in 1.5 liters of water, suspended until the whole became uniform, and subjected to an enzyme reaction in a 50 ° C constant temperature bath for 24 hours. . Thus, allergen-reduced rice was produced. Comparative Example 1 1.5 kg of a 1M sodium chloride solution at 50 ° C. was added to 1 kg of commercially available rice koshihikari as raw material rice, suspended until the whole became uniform, and subjected to salt extraction in a 50 ° C. constant temperature bath for 24 hours. After the extraction, the sodium chloride solution was separated from the rice (salt-treated), and the salt-treated rice was washed in running water for 1 hour. Thus, allergen-reduced rice was produced. Comparative Example 2 To 1 kg of commercially available rice Koshihikari, an enzyme aqueous solution in which 1.5 g of aspartic proteinase was dispersed in 1.5 liters of water was added, and the whole was suspended until the whole became uniform. The enzyme reaction was performed for 24 hours.
Thus, allergen-reduced rice was produced. Comparative Example 3 To 1 kg of commercially available rice Koshihikari, an enzyme aqueous solution obtained by dispersing 1.5 g of aspartic proteinase in 1.5 liter of water was added, suspended until the whole became uniform, and then kept in a 50 ° C. thermostat. The enzyme reaction was performed for 24 hours.
After the enzyme reaction, the enzyme solution and rice (enzyme-treated rice) were separated, and the enzyme-treated rice was washed in running water for 1 hour. 1.5 L of a 1 M sodium chloride solution was added to the enzyme-treated rice,
The whole was suspended until it became uniform, and salt extraction was performed for 24 hours in a 50 ° C constant temperature bath. Thus, allergen-reduced rice was produced. Test Example 5 Ground rice 3 obtained in Examples 1 and 2 and Comparative Examples 1 to 3
g to 60 ml of 4M urea-PBS (4M urea and 150m
PH with 20 mM phosphate buffer containing M sodium chloride
The mixture was shaken at room temperature for 3 hours, centrifuged at 10,000 rpm (10,000 rpm), and the supernatant (extract) was added.
Was isolated. The sample was diluted 100-fold with 4 M urea-PBS, 50 μl of the diluted solution was added to an ELISA plate, and the plate was allowed to stand at 4 ° C. overnight to allow the antigen to bind to the plate. The plate was washed three times with a PBS-T solution and 3%
After blocking with a BSA-PBS solution and allowing to stand for 2 hours, the plate was washed four times with a PBS-T solution.

The sera of four rice allergic patients and healthy subjects were diluted 10-fold with a 1% BSA-PBS solution, and 50 μl of the diluted solution was added. After standing for 2 hours, the plate was washed five times with a PBS-T solution. Subsequently, a peroxidase-conjugated anti-human IgE antibody (manufactured by Sigma) diluted 2,000-fold was added, left for 2 hours, and then washed six times with a PBS-T solution. Substrate solution (orthophenylenediamine 4
mg and H ₂ O ₂ phosphates containing 0.015% - added citrate buffer at that prepared in pH 5.0), the reaction was stopped by addition of 2N sulfuric acid after 30 minutes. The absorbance at 490 nm of this reaction solution was measured with an ELISA reader (I
gE-ELISA test). Table 2 shows the results.

[0032]

[Table 2]

As is clear from Table 2, in the allergen-reduced rice of Examples 1 and 2, a decrease in antigenicity was observed. Test Example 5 The allergen-reduced rice obtained in Example 1, Example 2 and Comparative Example 3 was cooked by a usual method.
The allergen-reduced rice of Example 2 has rice grains that are too soft and too sticky, and the allergen-reduced rice of Comparative Example 3 has the rice grains themselves that are fragile and easily crumbled. It was not suitable.
Then, after steaming the allergen-reduced rice of Example 1 and Example 2 with a steaming basket for 10 to 15 minutes, immersion and absorption in warm water of 75 to 85 ° C for 1 to 5 minutes, the steamed rice is loosened,
Each g was filled in a retort pouch and sealed and sterilized. The cooked rice prepared in this manner had strong rice grains and was suitable as cooked rice.

[0034]

According to the method for producing allergen-reduced rice of the first aspect of the present invention, the raw rice is immersed in an aqueous salt solution at 40 to 60 ° C., and the salt-soluble protein in the raw rice is extracted. Since the proteinase or the aspartic proteinase is allowed to act on the protein, the protein as an allergen in rice can be efficiently removed at a high removal rate. Further, the obtained allergen-reduced rice can maintain the shape of rice grains and is suitable for making rice.

The processed food using the allergen-reduced rice according to claim 2 is obtained by immersing raw rice in a salt aqueous solution at 40 to 60 ° C.
It is obtained by extracting the salt-soluble protein in the rice and subsequently processing the allergen-reduced rice treated with lactic acid bacteria-derived proteinase or aspartic proteinase. , Dango,
It can be used for mochi, pilaf, noodles and the like.

[Brief description of the drawings]

FIG. 1 is a chart showing an albumin extraction effect depending on the temperature of a salt aqueous solution.

FIG. 2 is a chart showing the albumin degrading effect depending on the type of enzyme.

FIG. 3 is a chart showing the allergen reduction of Example 1 and the antigenicity of raw rice with albumin.

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[Procedure amendment]

[Submission date] July 3, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction contents]

[Document Name] Statement

Title: Method for producing allergen-reduced rice, and processed food using allergen-reduced rice

[Claims]

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing allergen-reduced rice, and more particularly to a method for producing allergen-reduced rice capable of efficiently removing allergen from raw rice. The present invention also relates to a processed food using allergen-reduced rice.

[0002]

In recent years, food allergy sufferers are rapidly increasing with changes in living environment such as eating habits and lifestyle. As one of these treatments, alternative diets with other non-allergenic similar foods have been attempted to limit the intake of foods that cause allergic reactions. One example is the rapid increase in allergy to rice, and rice allergy sufferers generally use rice instead of rice.
There is a problem that the taste is compensated for by means of barbs, canes and the like, and it is not possible to obtain a satisfactory taste.

On the other hand, studies on allergens causing such food allergies have been advanced, and in the case of rice, it is clear that a lot of allergens are present in the globulin fraction and albumin fraction which are salt-soluble fractions, especially in the albumin fraction. [Miki Matsuda et al., Agric. Bio
l. Chem 52 (6) 1465-1470 (198
8); Miki Matsuda et al., Agric. Biol. Chem5
5 (2) 509-513 (1991)]. It has also been confirmed that salt-insoluble components include salt-insoluble allergens that respond to 20 to 30% of rice allergic patients [for example, Yoshio Ikezawa et al., Annual Report of the Japan Lidiaoli Association, 13, 41. -60 (1990)].

[0004] For this reason, it has been studied to mainly remove salt-soluble fractions that cause allergens from rice and the like.
Japanese Patent Publication No. 6-9472 discloses that a protease is allowed to act on a cereal material containing starch as a main component, and the solubility of the salt-soluble protein in the cereal is increased to 80% or more by 10% trichloroacetic acid solubility. A cereal in which allergens are reduced by hydrolyzing proteins in the cereal and removing soluble components is disclosed. However, this cereal is very expensive due to its special production method, and is not suitable for allergy sufferers to use it as a daily staple food.

[0005] JP-A-6-253758 discloses a method for producing a cereal preparation with reduced allergen by allowing collagenase to act on cereals such as rice. This publication describes that salt water can be acted on before or after the action of collagenase on cereals. However, in this method, cereals such as rice must be in the form of powder or paste, so that it is difficult to reduce allergens in the state of rice grains.

The present invention has been made on the basis of the above-mentioned object, and it is an object of the present invention to efficiently and at a high removal rate an albumin fraction, which is a major component of allergen in rice, from proteins in raw rice. An object of the present invention is to provide a method for producing possible allergen-reduced rice. Further, it is possible to provide a method for producing an allergen-reduced rice that can efficiently remove an albumin fraction from rice grains at a high removal rate, maintain the shape of rice grains after treatment, and is suitable for making rice. With the goal. Further, another object of the present invention is to provide a processed food using the allergen-reduced rice obtained by processing the obtained allergen-reduced rice.

[0007]

Means for Solving the Problems In view of the above-mentioned problems, as a result of intensive studies, the present inventors have found that the efficiency of removing salt-soluble proteins varies greatly depending on the temperature of the salt aqueous solution, and that the salt aqueous solution in a predetermined temperature range is not soluble in salt. proteins, in particular found that excellent extraction force of the albumin fraction, if the action by selecting lactic acid bacteria-derived proteinase a over peptidase or aspartic proteinase Lee proteinase as a salt solution and proteolytic enzymes of this temperature range,
It has been found that proteins in the raw rice, particularly the albumin fraction, can be removed at a high removal rate. In addition, the present inventors, the action procedure of the salt aqueous solution and the protease,
First, after extracting the salt-soluble protein in the raw rice with a salt solution in a predetermined temperature range and then decomposing and removing the remaining protein with a predetermined protease, the protein can be removed efficiently, and as a result, It has been found that the obtained allergen-reduced rice maintains the rice grain shape firmly and is suitable for rice cooking. The present invention has been made based on these.

[0008] That is, in the method for producing allergen-reduced rice according to claim 1 of the present invention, the raw rice is immersed in an aqueous salt solution at 40 to 60 ° C, and the salt-soluble protein in the raw rice is extracted. it is intended to act from proteinase a over peptidase or aspartic flop <br/> loteprednol Lee kinase.

[0009] Therefore, allergen proteins in rice can be removed efficiently and at a high removal rate. The reason why such an effect can be obtained is that the raw rice is first prepared in the range of 40 to 6
The salt-soluble allergen is extracted and removed by immersion in a relatively high-temperature salt aqueous solution at 0 ° C., and further, a specific protease is allowed to act thereon to decompose and remove the remaining salt-soluble and salt-insoluble proteins, which are allergens. Because it is. Moreover, in the method of the present invention, since the step of decomposing with the protease is provided after the extraction of the salt aqueous solution, the salt contained in the raw rice is diluted by the proteolysis step, and the water content in the allergen-reduced rice is reduced. Since the rate is high, the shape of rice grains is well maintained.

In the processed food using the allergen-reduced rice according to claim 2 of the present invention, the raw rice is immersed in an aqueous salt solution at 40 to 60 ° C. to extract the salt-soluble protein in the raw rice. is obtained by processing the allergen-reducing rice obtained by the action of lactic acid bacteria-derived proteinase a over peptidase or aspartic <br/> proteinase Lee proteinase Te. Therefore, it can be used for cooked rice, packaged food, dried rice, porridge, dango, rice cake, pilaf, noodles, and the like.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. In the present invention, there is no particular limitation on the raw rice to be reduced in allergens, and any rice such as japonica rice and indica rice can be used. Japonica rice is preferred in view of the dietary habits of Japanese people. Also, this raw rice is
It is preferable to use one that has been whitened to 80 to 95%, particularly 85 to 90%.

[0012] Further, as the salt used for the extraction of the aqueous salt solution,
Inorganic salts such as hydrochloride, sulfate, carbonate or phosphate can be used. On the other hand, alkali metal salts such as sodium salt and potassium salt can be used. Particularly, sodium chloride (salt) is preferable.

[0013] The proteolytic enzymes, proteins, in particular since the decomposition efficiency of the albumin is most favorable, ended the aspartic proteinase Lee proteinase (Amano as the allergens in the US among various proteolytic enzymes ,
Nagase biochemical sale Co., Ltd., etc.), the use of lactic acid bacteria-derived (Lactobacillus casei) proteinase A over zero. By using these proteolytic enzymes, it is possible to sufficiently decompose the albumin fraction that becomes an allergen, while suppressing the degradation of proteins that do not become an allergen as much as possible.

Next, a method for producing the allergen-reduced rice of the present invention, in which the raw rice is treated with the salt and the protease described above, will be described. First, in the present invention, the raw rice is immersed in a salt solution (salt solution extraction step). At this time, an aqueous solution having a temperature range of 40 to 60 ° C. is used as the salt aqueous solution. This is because the temperature of the salt aqueous solution is 4
If the temperature is lower than 0 ° C., the removal rate of the salt-soluble protein, especially the albumin fraction is not sufficient, while if it is higher than 60 ° C., starch flows out of the raw rice and the rice grains become small. Further, the concentration of the salt aqueous solution is preferably 0.05 to 5 molar. The concentration of the salt aqueous solution is less than 0.05 molar,
Alternatively, when the concentration exceeds 5 molar, the outflow of the salt-soluble protein as an allergen is not sufficient, and when the concentration of the salt aqueous solution exceeds 5 molar, the obtained allergen-reduced rice tends to become brittle. In particular, the concentration of the salt aqueous solution is set to 0.5 to 2
By setting the molar concentration, the salt-soluble protein can be more favorably extracted. The amount of the salt aqueous solution as described above is not particularly limited as long as the raw rice is completely immersed. For example, 1.5 times the amount of the raw rice may be used.

[0015] The time required for the salt aqueous solution extraction step may be appropriately set according to the concentration and temperature of the salt aqueous solution, and is usually about 12 to 36 hours, for example, about 24 hours.

[0016] After this manner exit brine solution extracting step, separating and processing rice and salt solution, washed, the processing rice to, lactic acid bacteria-derived proteinase A over peptidase or aspartic proteinase Lee proteinase (hereinafter, (Referred to simply as a specific protease) (enzymatic degradation step). In this case, the amount of the specific protease is preferably 0.01 to 5 parts by weight based on 100 parts by weight of the treated rice. If the amount of the specific protease is less than 0.01 part by weight, the protein as an allergen is not sufficiently degraded, while if it exceeds 5 parts by weight, rice grains are brittle and easily broken. In particular, the amount is preferably 0.05 to 0.2 parts by weight based on 100 parts by weight of the treated rice.
Such a specific proteolytic enzyme has an amount of 10 to 10
If necessary, a surfactant, an organic acid such as citric acid as a pH adjuster, etc. are added to about twice the amount of water, and the temperature is within the activation temperature range of the specific protease, for example, from room temperature to 55 ° C.
The fermentation treatment is performed within the temperature range described above and under pH conditions. The enzymatic treatment step may be performed for a time sufficient to decompose proteins not extracted in the above-described salt aqueous solution extraction step, and is usually performed for about 12 to 36 hours, for example, about 24 hours.

In the method for producing allergen-reduced rice of the present invention as described above, the protein as an allergen can be sufficiently removed even if granular rice is used as the raw rice instead of crushed rice. In particular, in the case of albumin, about 1/32 or less of the raw rice (ELISA inhibition test (ELISA
-Inhibition). Moreover, the allergen-reduced rice thus obtained has a low degree of embrittlement with respect to the raw rice, so that it can maintain rice graininess and is suitable for steaming or the like to produce cooked rice.

Next, a processed food using the allergen-reduced rice of the present invention will be described. Processed food using the allergen-reduced rice of the present invention is obtained by processing the allergen-reduced rice obtained as described above. It may be immersed, put into a container such as a retort pouch or a plastic molded container, sealed, and then sterilized. Further, the allergen-reduced rice is boiled in a porridge, α-amylase is added to the rice, and the resulting liquid is liquefied. If necessary, fruit juice, milk, and the like are added to the liquefied product, thereby comprising the allergen-reduced rice. It can be a drink.

Further, the allergen-reduced rice obtained by the method of the present invention can be used for various foods in which other ordinary rice is used, such as dango, rice cake, pilaf and noodles. Can be.

Although the present invention has been described in detail above, the present invention is not limited to the above description, and various applications are possible without departing from the spirit of the present invention. For example, although the method of the present invention can remove allergens satisfactorily from raw rice in the form of rice granules, the method does not need to be in the form of rice granules. May be applied. Further, the concentration of the protease, the concentration of the salts, the treatment time, and the like can be appropriately set according to the desired removal rate of the allergen substance such as albumin.

[0021]

The present invention will be described in more detail with reference to the following specific examples. Test Example 1 Confirmation of albumin extraction effect by temperature of salt aqueous solution 1M (molar concentration) per 1 kg of commercially available Koshihikari as raw material rice
Add 1.5 liters of sodium chloride solution each, suspend until the whole becomes homogeneous, 5, 25, 50 and 60 ° C
The salt extraction was performed for 24 hours in each of the thermostats. After extraction,
The sodium chloride solution was separated from the treated rice, and the treated rice was washed in running water for 1 hour. The treated rice was immediately freeze-dried and pulverized. The absorbance at 490 nm of the treated rice thus pulverized was measured by an ELISA test.

The ELISA test was performed as follows. 10 ml of PB per 1 g of crushed treated rice sample
S (prepared to pH 7.4 with a 20 mM phosphate buffer containing 150 mM sodium chloride) was added, the mixture was allowed to stand at 4 ° C. for 3 hours, sonicated for 10 minutes, and then centrifuged (10000 rpm) for 10 minutes. Then, the supernatant (extract) was separated.

On the other hand, a rice albumin fraction was added to an ELISA plate so that the amount of rice albumin was 1 μg. 4
The plate was allowed to stand overnight at 0 ° C. to bind to the plate. The plate was washed three times with a PBS-T solution (prepared to pH 7.4 with a 20 mM phosphate buffer containing 150 mM sodium chloride and 0.05% Tween-20), and washed with 3% B
After blocking with an SA (bovine serum albumin) -PBS solution and allowing to stand for 2 hours, the plate was washed with PBS-T solution for 4 hours.
Washed twice.

Then, 50 μl of the extract diluted 4 times
And 50 μl of a 300,000-fold diluted anti-rice albumin monoclonal antibody (25B9), and allowed to stand at 4 ° C. overnight. This reaction solution was added to the plate, and after standing for 2 hours, the plate was washed five times with a PBS-T solution. Subsequently, a 10,000-fold diluted peroxidase-conjugated anti-mouse Ig
The G antibody was added, and after standing for 2 hours, the plate was washed six times with a PBS-T solution. Substrate solution (orthophenylenediamine 4mg
Phosphoric acid containing H ₂ O ₂ 0.015% - added citrate buffer at that prepared in pH 5.0), the reaction was stopped by addition of 2N sulfuric acid after 30 minutes. 49 of this reaction solution
The absorbance at 0 nm was measured with an ELISA reader. Also,
The absorbance at 490 nm was similarly measured with an ELISA reader for the extracts diluted 8, 16, 32 and 64 times. For comparison, the raw rice was subjected to an ELISA test at 490 nm in the same manner as the treated rice described above.
Was measured for absorbance. These results are shown in FIG.

As is clear from FIG. 1, the treated rice extracted with the salt aqueous solution showed an increase in absorbance at 490 nm as compared with the raw rice, and a decrease in antigenicity was observed. This tendency was greater as the temperature of the salt aqueous solution was improved. Particularly, in the salt aqueous solutions at 50 ° C. and 60 ° C., the antigenicity was reduced to 1/8 or less of that of the raw rice. In addition, although a decrease in antigenicity was observed in a 60 ° C. salt aqueous solution, starch flowed out and rice grains were thin and small, and the extraction temperature with a salt aqueous solution was limited to 60 ° C. Test Example 2 Confirmation of Albumin Degrading Effect by Kind of Enzyme To 1 kg of commercially available rice Koshihikari, actinase,
Metaropurote Lee kinase, aspartic proteinase Lee donors <br/> peptidase and lactic acid bacteria-derived proteinase A over peptidase 1.5g respectively 1.
An enzyme aqueous solution dispersed in 5 liters of water is added, and the whole is suspended until it becomes uniform.
The enzyme reaction was performed for hours. Then, the treated rice after the reaction was immediately freeze-dried and pulverized.

Using the milled rice thus treated as a sample, the antigenicity of the rice against the albumin fraction, which is a major allergen of rice, was determined by an ELISA test using a rice albumin monoclonal antibody in the same manner as in Test Example 1 described above.
The absorbance at 0 nm was measured. For comparison, the absorbance at 490 nm was similarly measured for the raw rice by the ELISA test. These results are shown in FIG. Note that the aspartic proteinase Lee proteinase, was also measured absorbance at 490nm in the extraction solution diluted to 2-fold.

As is clear from FIG. 2, the treated rice treated with the enzyme showed an increase in absorbance at 490 nm as compared with the raw rice, and a decrease in antigenicity was observed. This trend, aspartic proteinase Lee proteinase and lactic acid bacteria-derived flop <br/> particularly high loteprednol A over Ze, antigenicity was decreased to less than one-eighth of Rice. Watanabe et al.'S method (J. Food.S
The solubility of the salt-soluble protein in 10% trichloroacetic acid was determined in accordance with Science 55 (3) 781-783 (1990). The results were 72% and 69%, respectively. Example 1 To 1 kg of commercially available rice Koshihikari was added 1.5 liters of a 1 M sodium chloride solution at 50 ° C, suspended until the whole became uniform, and subjected to salt extraction in a 50 ° C constant temperature bath for 24 hours. After the extraction, the sodium chloride solution and the rice (salt extracted rice) were separated, and the salt-treated rice was washed in running water for 1 hour. Aspartic proteinase Lee proteinase 1.5g of the enzyme solution was added dispersed 1.5 liters of water to the salt-extracted rice, the whole suspended in 24 hours enzymatic reaction respectively in a thermostatic bath at 50 ° C. until homogeneous Then, rice with reduced allergen was produced. Test Example 3 Ground Allergen Reduced Rice 1
g in the same manner as in Test Example 1 described above, using a rice albumin monoclonal antibody to determine the antigenicity against the albumin fraction, which is a major rice allergen, using a stock solution, 2 fold, 4 fold, and 1 fold.
The absorbance at 490 nm was measured in the extract diluted 6 times, 32 times and 64 times by the ELISA test. Further, for comparison, the absorbance at 490 nm was measured by an ELISA inhibitor test in an extract diluted 4 times, 16 times, 32 times and 64 times with respect to the raw rice. These results are shown in FIG.

As is clear from FIG. 3, the allergen-reduced rice treated by the method of the present invention is 49 times less than the raw rice.
Significant improvement in absorbance at 0 nm was observed, and it was confirmed that the antigenicity was reduced to 1/32 or less of the raw rice. Test Example 4 The allergen-reduced rice obtained in Example 1 was cooked and fed as a staple food to six rice allergic patients, and the state of improvement of atopic dermatitis was observed. Table 1 shows the results.

[0029]

[Table 1]

As is clear from Table 1, all patients reduced the atopic dermatitis by the allergen-reduced rice of Example 1, and allergen-causing protein in the rice was removed by the method of the present invention. You can see that it is done. Example 2 1.5 kg of a 1 M sodium chloride solution at 50 ° C was added to 1 kg of commercially available Koshihikari as raw rice, suspended until the whole became homogeneous, and subjected to salt extraction in a 50 ° C constant temperature bath for 24 hours. After the extraction, the sodium chloride solution was separated from the rice (salt-treated), and the salt-treated rice was washed in running water for 1 hour. The aqueous enzyme solution is dispersed lactic acid bacteria-derived proteinase A over Ze 1.5g 1.5 l of water was added to this salt treatment rice, whole suspension to 50 ° C. in a constant temperature bath at 24 h enzymatic each reaction until homogeneous Was done. Thus, allergen-reduced rice was produced. Comparative Example 1 1.5 kg of a 1M sodium chloride solution at 50 ° C. was added to 1 kg of commercially available rice koshihikari as raw material rice, suspended until the whole became uniform, and subjected to salt extraction in a 50 ° C. constant temperature bath for 24 hours. After the extraction, the sodium chloride solution was separated from the rice (salt-treated), and the salt-treated rice was washed in running water for 1 hour. Thus, allergen-reduced rice was produced. Commercially available Koshihikari 1kg Comparative Example 2 Rice, aspartic proteinase Lee proteinase 1.5g was added the enzyme solution prepared by dispersing 1.5 liters of water, constant temperature bath of suspended until the whole becomes uniform 50 ° C. For 24 hours. Thus, allergen-reduced rice was produced. Commercially available Koshihikari 1kg Comparative Example 3 Rice, aspartic proteinase Lee proteinase 1.5g was added the enzyme solution prepared by dispersing 1.5 liters of water, constant temperature bath of suspended until the whole becomes uniform 50 ° C. For 24 hours. After the enzyme reaction, the enzyme solution and rice (enzyme-treated rice) were separated, and the enzyme-treated rice was washed in running water for 1 hour. 1.5 L of a 1 M sodium chloride solution is added to the enzyme-treated rice, suspended until the whole becomes uniform, and is placed in a 50 ° C constant temperature bath.
Salt extraction was performed for 4 hours. Thus, allergen-reduced rice was produced. Test Example 5 Ground rice 3 obtained in Examples 1 and 2 and Comparative Examples 1 to 3
g to 60 ml of 4M urea-PBS (4M urea and 150m
PH with 20 mM phosphate buffer containing M sodium chloride
The mixture was shaken at room temperature for 3 hours, centrifuged at 10,000 rpm (10,000 rpm), and the supernatant (extract) was added.
Was isolated. The sample was diluted 100-fold with 4 M urea-PBS, 50 μl of the diluted solution was added to an ELISA plate, and the plate was allowed to stand at 4 ° C. overnight to allow the antigen to bind to the plate. The plate was washed three times with a PBS-T solution and 3%
After blocking with a BSA-PBS solution and allowing to stand for 2 hours, the plate was washed four times with a PBS-T solution.

The sera of four rice allergic patients and healthy subjects were diluted 10-fold with a 1% BSA-PBS solution, and 50 μl of the diluted solution was added. After standing for 2 hours, the plate was washed five times with a PBS-T solution. Subsequently, a peroxidase-conjugated anti-human IgE antibody (manufactured by Sigma) diluted 2,000-fold was added, left for 2 hours, and then washed six times with a PBS-T solution. Substrate solution (orthophenylenediamine 4
mg and H ₂ O ₂ phosphates containing 0.015% - added citrate buffer at that prepared in pH 5.0), the reaction was stopped by addition of 2N sulfuric acid after 30 minutes. The absorbance at 490 nm of this reaction solution was measured with an ELISA reader (I
gE-ELISA test). Table 2 shows the results.

[0032]

[Table 2]

As is clear from Table 2, in the allergen-reduced rice of Examples 1 and 2, a decrease in antigenicity was observed. Test Example 5 The allergen-reduced rice obtained in Example 1, Example 2 and Comparative Example 3 was cooked by a usual method.
The allergen-reduced rice of Example 2 has rice grains that are too soft and too sticky, and the allergen-reduced rice of Comparative Example 3 has the rice grains themselves that are fragile and easily crumbled. It was not suitable.
Then, after steaming the allergen-reduced rice of Example 1 and Example 2 with a steaming basket for 10 to 15 minutes, immersion and absorption in warm water of 75 to 85 ° C for 1 to 5 minutes, the steamed rice is loosened,
Each g was filled in a retort pouch and sealed and sterilized. The cooked rice prepared in this manner had strong rice grains and was suitable as cooked rice.

[0034]

According to the method for producing allergen-reduced rice of the first aspect of the present invention, the raw rice is immersed in an aqueous salt solution at 40 to 60 ° C., and the salt-soluble protein in the raw rice is extracted. since those exerting derived proteinase a over peptidase or aspartic proteinase Lee Na <br/> over zero, it is possible to remove the protein of the allergens in the US efficiently and with high removal rate. Further, the obtained allergen-reduced rice can maintain the shape of rice grains and is suitable for making rice.

The processed food using the allergen-reduced rice according to claim 2 is obtained by immersing raw rice in a salt aqueous solution at 40 to 60 ° C.
Extracting salt-soluble proteins in該米, since then it is obtained by processing the allergen-reducing rice obtained by the action of lactic acid bacteria-derived pro <br/> Te A over peptidase or aspartic proteinase Lee proteinase, rice And containerized food, dried rice, porridge, dango,
It can be used for mochi, pilaf, noodles and the like.

[Brief description of the drawings]

FIG. 1 is a chart showing an albumin extraction effect depending on the temperature of a salt aqueous solution.

FIG. 2 is a chart showing the albumin degrading effect depending on the type of enzyme.

FIG. 3 is a chart showing the allergen reduction of Example 1 and the antigenicity of raw rice with albumin.

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

FIG. 2

Claims (2)

[Claims] 1. An allergen characterized by immersing raw rice in a salt solution at 40 to 60 ° C. to extract a salt-soluble protein in the raw rice, and then allowing a lactic acid bacterium-derived proteinase or aspartic proteinase to act thereon. Method for producing reduced rice. 2. Raw rice is immersed in an aqueous salt solution at 40 to 60 ° C. to extract salt-soluble proteins in the raw rice, and then allergen-reduced rice treated with lactic acid bacteria-derived proteinase or aspartic proteinase is used. A processed food using allergen-reduced rice, which is obtained by processing.