JPH05292906A - Allergen-reduced rice prepared food, its production and processed food containing the same rice prepared food - Google Patents

Abstract

PURPOSE:To obtain the subject prepared food efficiently reduced in allergen protein without impairing quality of rice itself and useful for patients, etc., having allergy to foods, by treating rice low in globulin content with water, etc., to remove a protein having a prescribed molecular weight. CONSTITUTION:Rice having low globulin content and being <=10% in globulin content in a protein contained in rice is treated with water or an aqueous solution of a salt such as common salt (preferably at 0.5-1.5 mole concentration). Thereby, a protein having 12000-30000 molecular weight is substantially removed to provide the objective prepared food. Furthermore, the objective rice processed food such as rice cracker is obtained by using this prepared food.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an allergen-reduced rice preparation, a method for producing the same, and a processed food containing the same.
In particular, the present invention relates to allergen-reduced rice that can be used as food for patients who develop an allergic reaction to rice.

[0002]

2. Description of the Related Art In recent years, the number of food allergy patients has been rapidly increasing. This is due to the large amount of protein intake that accompanies westernization of eating habits, as well as other factors (for example, exhaust gas air pollution,
Or, changes in lifestyle such as Western-style houses with high airtightness and carpet are complicatedly overlapped, and various substances existing in the living environment are transformed into allergens.

A rapid increase in allergies to rice is one example. This type of food allergy has become common not only in children but also in adults, and it causes great psychological distress not only to the physical and mental distress of the individual but also to the parents and the whole family. Attempts have been made to treat food allergy patients by restricting or not allowing food intake. However, limiting food can interfere with life support and development. Therefore, it is one of the preferred methods to remove foods that cause allergies and to eat foods that do not damage other nutritional components.

As this kind of method, for example, Japanese Patent Laid-Open No. 2-16
As described in Japanese Patent No. 7040, a proteolytic enzyme is allowed to act to remove proteins involved in allergies contained in rice, and the solubility of 10% trichloroacetic acid in salt is 80%. A method of hydrolyzing until the above and removing the soluble component is known. However, this method has not yet been able to sufficiently remove the allergen, and 20 to 30% of rice allergic patients have not been improved.

Electrophoresis (SDS) is used as a component (allergen) specific to patients who are allergic to rice.
-PAGE) molecular weight of 12,000-30,000,
In particular, proteins with a molecular weight of around 16,000 are important.
(Hereinafter, the molecular weight of a protein in this specification is SDS-
It shall be calculated from the results of PAGE. )However,
For example, the method described in Japanese Patent Application Laid-Open No. 2-167040 could not be removed until it was sufficiently satisfied.

[0006]

DISCLOSURE OF THE INVENTION The present inventors have conducted a detailed analysis on various types of rice, and found that globulin content in rice proteins is 10% or more as in general commercially available rice such as Sasanishiki, Koshihikari, Nihonsari and Norin 8 It was found that the removal rate of rice is limited even if it is treated with the conventional method for reducing allergen.

As a result of diligent efforts to solve the above problems and provide as many rice allergy patients as possible, the present inventors have found that the globulin content, especially the molecular weight of 16,000.
It was found that an excellent allergen-reduced rice can be produced by salt water extraction using rice having a globulin content in the vicinity of 10% or less, and the present invention has been completed. That is, an object of the present invention is to provide an allergen-reduced rice preparation that is extremely effective as food for patients who develop an allergic reaction to rice.

[0008]

SUMMARY OF THE INVENTION The present invention therefore relates to a rice preparation in which rice with low globulin content is substantially free of proteins having a molecular weight of 12,000-30,000.
Further, the present invention is a method for producing a rice preparation in which rice having a low globulin content is substantially removed of proteins having a molecular weight of 12,000 to 30,000, which is characterized by treating rice having a low globulin content with a salt solution. Also related to. Furthermore, the present invention provides a molecular weight of 12,000 contained in rice with a low globulin content.
It also relates to a processed rice food product obtained using a rice preparation substantially free of ˜30,000 proteins.

The allergen-reduced rice preparation of the present invention is one in which proteins having a molecular weight of 12,000 to 30,000, particularly, a molecular weight of about 16,000 are removed or reduced.

The rice preparation of the present invention can be prepared by subjecting rice having a low globulin content to an allergen-reducing treatment. Here, the allergen reduction treatment is a protein extraction operation using an aqueous salt solution. In the allergen reduction process, for rice with low globulin content,
By stirring in an aqueous salt solution with the product temperature at the time of extraction above the freezing point to 15 ° C. or less, and performing protein extraction treatment with an aqueous salt solution, the extraction time is extremely short and the number of extractions is small,
Allergen proteins can be efficiently removed and separated. The product temperature is the temperature of the salt aqueous solution in which rice is dispersed. When rice, an aqueous salt solution, water, or an enzyme or a surfactant used in the present invention is used, each or all of them may be cooled in advance to a freezing point of the respective substance or higher to 15 ° C. or lower before use. More preferably, and after each or all of the above substances are mixed, they may be cooled to a temperature above the freezing point and below 15 ° C. Furthermore, by adding a proteolytic enzyme to the above salt aqueous solution, protein elution and removal are promoted, and when a surfactant is added to this, the proteolytic enzyme permeates rice and its action is promoted. preferable.

The low globulin rice with a low globulin content used in the present invention has a globulin content in the protein of 0.5 to 10%, preferably 0.5 to 8%, more preferably 0.5 to 5%, and especially The globulin having a molecular weight of 16,000 has a content of 0.5 to 7%, preferably 0.5 to 5%, and it is used in the state of rice grains which have been polished or unpolished, or crushed. As rice that produces low globulin rice, which is a raw material of the present invention, there is 85KG4 strain varieties rice produced by the National Institute for Agrobiological Resources of the Ministry of Agriculture and Fisheries. As the low globulin rice, it is preferable that part or all of the rice grains tend to be powdery, and especially the central part of the grains,
A slight or slight tendency toward powder is preferred.

In the method of the present invention, a surfactant and / or a proteolytic enzyme can be optionally used, and as the proteolytic enzyme, those described in JP-A No. 2-167040 can be used. As the surfactant, it is particularly preferable to use polyglycerin ester or lysophospholipid (for example, lysolecithin). Preferable proteolytic enzymes used for promoting elution of the protein to be removed include, for example, papain, bromelain, trypsin, pepsin, pancreatin, actinase and α-chymotrypsin. The amount of proteolytic enzyme used is 0.05 to 5 parts by weight with respect to 100 parts by weight of the salt aqueous solution, and the amount of surfactant used is 100 parts by weight of the salt aqueous solution.
About 0.02 to 5 parts by weight is preferable. In addition, prior to the enzymatic reaction, the salt-containing aqueous solution containing rice is subjected to a pressure reduction or a pressure treatment to promote salt water extraction removal or the enzymatic reaction.
The degree of decompression is 10 to 50 mmHg and the degree of pressurization is 2 to 10 kg.
/ Cm ² is suitable.

The allergen-reduced rice of the present invention is prepared by adding an aqueous salt solution to rice having a low globulin content, and the product temperature is above the freezing point to 1 or less.
It can be obtained by allowing to stand still or stirring at 5 ° C. or lower and then removing the eluted protein fraction. When the product temperature is below the freezing point, the amount of allergen protein extracted once decreases and the extraction efficiency decreases. If the product temperature exceeds 15 ° C, the extraction efficiency will decrease as in the case below the freezing point. On the other hand, also in solid-liquid separation operations such as stationary separation, centrifugation, filtration separation, and membrane separation, the efficiency is inferior in terms of time and yield as compared with the case of treating at 15 ° C or lower. In the present invention, after the extraction treatment, the preparation can be desalted or without desalting.

In the allergen-reduced rice preparation of the present invention, 1 g of the powder was added with 10 ml of 1M NaCl to give 30
When left standing or stirred at room temperature for minutes, the protein concentration in the supernatant is 400 μg / ml or less, preferably 200 μg
It is extremely effective if it is g / ml or less, and further 100 μg / ml or less.

As the salt solution which is the extractant solution of the present invention, saline is most suitable, but carbonates and sodium salts such as sodium bicarbonate and the like are preferable, and various other phosphates, potassium salts, Calcium salts, sulphates or hydrochlorides such as potassium chloride, sodium sulphate,
An aqueous solution of sodium polyphosphate or the like can also be used.
The salt water concentration is 0.05 to 3 molar concentration, preferably 0.5 to
A 1.5 molar concentration is suitable.

Specifically, one of the preferred embodiments of the method of the present invention will be described.
A salt aqueous solution having a concentration of M to 3M or higher than the freezing temperature, for example, a saline solution is added to bring the product temperature to the freezing temperature or higher to 15 ° C or lower,
Let stand for 2 minutes to 48 hours or stir, for example, if rice grains remain, 6 hours to 48 hours, preferably 8 hours to 24 hours,
If it is a powder, it is left standing or stirred for 2 minutes to 8 hours, preferably 5 minutes to 3 hours, and has a molecular weight of 10,000 to 30,000, especially a molecular weight of 1
Protein fraction around 6,000, preferably molecular weight 30,000
~ 40,000 Especially protein fraction around 33,000 and molecular weight 50,000-60,000 Especially 52,000-57,000
The protein fraction of (1) is eluted and then separated by a method such as standing or centrifugation to obtain the allergen-reduced rice preparation of the present invention. This operation is repeated several times if necessary. Usually, about 1 to 3 times is enough. Further, it is naturally possible to carry out this operation not in a batch system but in a continuous system. It is also possible to elute with a salt aqueous solution and then wash with water to remove salt or more strictly remove water-eluting allergen. Whether the target protein fraction has been sufficiently eluted to obtain the allergen-reduced rice preparation is determined by confirming the presence of the protein fraction to be removed by electrophoresis, high performance liquid chromatography, etc. be able to. For more precise measurement, an immunological analysis method such as an enzyme immunoassay method or a radioimmunoassay method may be used.

The thus-prepared allergen-reduced rice preparation of the present invention may be used as it is, or may be dried and powdered or granulated depending on the intended use. The drying method may be any method as long as it is a method used for drying food. For example, spraying, vacuum, hot air, freezing, sun, electromagnetic waves, or a drying method combining these may be used. For powdering, for example, roll type, pestle type,
A shock method and the like can be mentioned.

The low allergenized rice preparation obtained by the present invention may be used as it is after being cooked, or may be used as a rice cracker such as hail, rice cracker, rice cake, rice noodles, rye, etc. It can also be used for the processing applications, and a delicious cooked product equivalent to ordinary rice can be obtained. Further, it can be used together as a part of other food ingredients for allergic patients, and can be used for producing macaroni, spaghetti, udon, buckwheat, bread, cookies, confectionery, etc. containing hypoallergenic rice, for example. Of course, it can be used not only for humans but also for animal feed such as pet food. Therefore, its use and usage are not particularly limited.

Next, an inspection method for confirming the effect of the present invention will be described in the following experimental examples. Experimental Example 1 Low globulin rice (globulin content in rice protein 4
%; 76 ml Tris citrate buffer (pH 7.4) containing 10 ml of 1M-NaCl was added to 1 g of the crushed rice product (rice from rice of 85KG4 line), and the mixture was stirred for 14 hours at 4 ° C., then for 20 minutes. Centrifugation (10000 x G) was performed to separate the supernatant (extract). The extract solution was 20 mM phosphate buffer solution (pH 7.4) containing 0.15 mM NaCl, and a dialysis tube with a pore size molecular weight of 3500 cuts was used at 2 ° C at 2 ° C.
It was dialyzed for 4 hours. The dialyzed extract was freeze-dried to obtain a salt extract (hereinafter referred to as extract A). The rice of the 85KG4 low globulin strain used in this experimental example was produced by the following method. That is, seeds of Koshihikari (rice variety) were subjected to γ-ray irradiation to induce mutation, and the resulting seeds were cultivated to obtain rice. The thus-obtained rice was subjected to protein analysis to obtain target mutant varieties with low globulin content, especially globulin having a molecular weight of 16,000.

The rice residue after extraction is 1M NaCl for 14 hours.
20 ml of 76 mM Tris citrate buffer (pH 7.4) containing
It was stirred at and washed with water for another 2 hours. At this time, the protein concentration of the supernatant was 14 μg / ml (total 10 ml). After freeze-drying the rice residue, 10 ml of a urea extractant (76 mM Tris citrate buffer containing 7 M urea and 20 mM 2-mercaptoethanol) was added to 0.8 g of the freeze-dried product, and the mixture was stirred at room temperature for 10 minutes. Centrifuge for 20 minutes (10000 x G)
The supernatant (urea extract) was separated with and purified in the same manner as the salt extract (hereinafter referred to as extract B).

Next, the extract A and the extract B corresponding to a protein amount of 2 mg were respectively added with SDS at a final concentration of 1% and 2-
Mercaptoethanol 1%, Tris-hydrochloric acid buffer solution 1 mM and glycerin 20% were added to each, and distilled water was added to 1 ml to prepare an electrophoresis (SDS-PAGE) sample. Both samples were heat-treated at 100 ° C. for 2 minutes, and BPB (bromophenol blue) was added so as to be 0.05%. 5 μl of the sample was added to 10 to 20% gradient SDS-polyacrylamide gel and 70 at 40 mA.
The extract A and the extract B were fractionated by electrophoresis for minutes. Next, the fractionated components of the extract A and the extract B were electrophoretically transferred onto an Immobilon P membrane manufactured by Millipore at 80 mA constant current for 1 hour. After blocking the transfer membrane with 5% skim milk, the serum of a rice allergy patient and the control adult serum without rice allergy were reacted at room temperature for 14 hours. After washing the membrane, biotin-conjugated anti-human I
A 500-fold dilution of gE antibody (manufactured by Tago) and avidin conjugated with peroxidase (1000-fold dilution) were each added to 2
The reaction was carried out at 37 ° C for a time, and the IgE antibody bound to the membrane was enzyme-labeled.

On the other hand, DAB (3,3-diamino-benzidine tetrah
25 mg of 50 mM Tris-HCl buffer (pH
7.6) Dissolve in 100 ml, hydrogen peroxide (30%) 50
μl was added to prepare a color developing solution. This color-developing solution was added to the transfer membrane to detect IgE antibody. As is clear from Tables 1 and 2 showing the results, patient serum (serum No. 1 to N
o. 7) reacted strongly with Extract A (Table 1). On the other hand, the patient sera hardly reacted with the extract B, and no difference was observed with the sera of healthy persons (serum No. 8 to No. 10),
The fraction component specifically recognized by patient serum was not found in Extract B (Table 2).

Experimental Example 2 To 1 g of the low globulin rice crushed product used in Experimental Example 1, 10 ml of the urea extractant described in Experimental Example 1 was added, and
Extract and purify rice protein in the same manner as
Extract C was obtained. Extract B and Extract C of Experimental Example 1
1 g of each of the above was dissolved in 10 ml of a urea extractant, and 100 μl of the solution was added to 900 μl of a 0.5 M saline solution containing 50% glycerin, and the mixture was stirred at 4 ° C. for 14 hours. After centrifugation (10,000 × G) for 20 minutes, supernatants were obtained and designated as Extract B and Extract C, respectively.

A rice allergic patient was placed in a prone position, and one arm was sterilized with alcohol cotton and naturally dried, and then the extract B, the extract C and the control (50% glycerin, 0.5M NaCl solution) were used as the antigen solution. It was added drop by drop. A sterilized needle was pierced into the skin in an oblique direction through the dropped antigen solution, and 20 minutes later, the presence or absence of wheal and redness around it was determined. Judgment was made by Sheldon JM, et al. (A
manual of clinical Allergy 159 WBSaunders Compan
y Philadelphia and London, 1967). That is, if it is the same as the control, it is negative (-), if it is difficult to judge whether redness is recognized (±), redness is recognized, but if the diameter is 21 mm or less (+), there is redness of 21 mm or more. If there was no wheal (++), and if both redness and wheal were observed, it was (+++). The results are shown in Table 3. As is clear from Table 3, in Extract B, no protein serving as an allergen was found, and in Extract C, it was found. That is, it is shown that rice treated with salt water does not have a protein having a molecular weight of 16,000 as an allergen.

Experimental Example 3 The same procedure as in Experimental Example 1 was carried out except that the powder of commercially available polished rice was used in place of the low globulin rice. The liquid was designated as Extract F. As is clear from Tables 4 and 5 showing the results, the patient sera (serum No. 1 to No. 7) strongly reacted with the extract E, and especially with the protein component fractionated to have a molecular weight of 30,000 or less. It reacted strongly (Table 4). Furthermore, patient serum (serum N
o. 1-No. In 7), about 2 out of 7 reacted with the protein component fractionated into extract F having a molecular weight of 30,000 or less, particularly the protein component fractionated at a molecular weight of 16,000. Molecular weight 3
It reacts with the fractionated protein of 0,000-40,000 or 50,000-70,000, and the difference with the healthy human serum is observed,
Fraction components specifically recognized by patient serum were also found in Extract F (Table 5).

Experimental Example 4 Urea extractant 10 described in Experimental Example 1 was added to 1 g of commercially available ground rice.
ml was added, and rice protein was extracted and purified in the same manner as in Experimental Example 1 to obtain an extract G. Extract F and extract G
Was determined in the same manner as in Experimental Example 2. The results are shown in Table 6.

[0027]

The present invention will be described in detail below with reference to examples, but these do not limit the scope of the present invention. Example 1 5 kg of low globulin rice (rice obtained from rice of 85KG4 low globulin strain used in Experimental Example 1; globulin content 3%) was placed in a container of 30 liters and 1M NaC was added.
18 kg of 1-solution was added, and the mixture was immersed in the product temperature of 4 ° C. for 24 hours, occasionally stirred, and allowed to stand, and then the rice and the extract were separated with a wire mesh of 500 μm. This operation was similarly repeated twice. Then, 20 liters of water was added to the obtained rice and left for 2 hours to remove the supernatant. The rice obtained by repeating this again is dried with a hot air dryer to obtain the low allergen rice 4.9 of the present invention.
got kg. When this low allergen rice was examined by an intradermal reaction in rice allergic patients, 23 were negative and 1 was positive. However, negative means (-) and positive means (++) or more. When 8 rice allergic patients were ingested in an amount of 80 g per day for 1 week, no onset caused by ingestion was observed.

Example 2 2 kg of low globulin rice (milled rice obtained from rice of line 85KG4: 3% globulin content) was placed in a 20 liter container, 15 kg of 1M NaHCO ₃ solution was added, and further 25 g of decaglycerin monooleate was added. Therefore, the mixture was stirred at a product temperature of 13 ° C. for 24 hours. The subsequent operation was the same as in Example 1. When this low allergen rice was examined by an intradermal reaction in rice allergic patients, 12 were negative and 0 were positive. However, negative means (-) and positive means (++) or more. In addition, when 5 rice allergic patients were ingested in an amount of 50 g per day for 1 week, no onset due to ingestion was observed.

Example 3 5 kg of the low globulin rice used in Example 1 was placed in a 30-liter container, 10 liters of a 1M NaCl solution and 1 g of lysolecithin were added, and the mixture was stirred for 30 minutes at a product temperature of 4 ° C., as in Example 1. The supernatant was separated. Further, the rice thus obtained was treated with 0.5M CaCl ₂ and 0.5M Na ₂ SO _{4 at a} temperature of 30 ° C.
20 liters of the mixed solution of No. 1 and 20 g of proteolytic enzyme (pronase) were added, and degassing was performed at 80 mmHg for 30 minutes,
After allowing to stand for a minute, the product temperature of the salt water was cooled to 7 ° C. and left for 30 hours with occasional stirring. Then, it was separated by sieving from the salt solution. Then water was poured over the sieve until the salt was gone. The obtained rice was placed in a dryer and dried with hot air at 40 ° C. to obtain 4.7 kg of the low allergen rice of the present invention. When this low allergen rice was examined by an intradermal reaction in rice allergic patients, 15 were negative and 0 were positive. However, negative means (-) and positive means (++) or more. Further, when 8 rice allergic patients were ingested in an amount of 50 g per day for 11 days, no onset due to ingestion was observed.

Comparative Example 1 1.8 kg of treated rice was obtained by the same method as in Example 3 except that 2 kg of commercially available polished rice (Sasanishi) was used.
When this treated rice was examined by an intradermal reaction of rice allergic patients, 14 were negative and 6 were positive.

Processed Food Production Example A rice cracker was produced from the rice obtained in Example 1 and Comparative Example 1 by a conventional method. That is, rice was steamed, kneaded, molded, frozen, dried, then baked, soy sauce was applied, and dried to obtain a rice cracker. Table 7 shows the results of comparison of the texture, baking color and flavor of the rice crackers thus obtained. That is, the rice cracker produced from the rice obtained in Example 1 was superior.

[0032]

INDUSTRIAL APPLICABILITY According to the present invention, an allergen-reduced rice preparation can be provided in which allergen proteins are efficiently removed and the original quality of rice is not impaired. It brings benefits.

[0033]

[Table 1]

[0034]

[Table 2]

[0035]

[Table 3]

[0036]

[Table 4]

[0037]

[Table 5]

[0038]

[Table 6]

[0039]

[Table 7]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shuichi Iida 3101-11 Omiya-machi, Naka-gun, Ibaraki Prefecture (72) Inventor Kazufumi Tsubaki 7-35 Higashiohisa, Arakawa-ku, Tokyo Asahi Denka Co., Ltd. (72 Inventor Takashi Suzuki 7-35 Higashiohisa, Arakawa-ku, Tokyo Asahi Denka Kogyo Co., Ltd.

Claims (6)

[Claims] 1. A protein having a molecular weight of 12,000 to 30,000 contained in rice having a low globulin content is substantially removed.
Rice preparation. 2. Production of a rice preparation from which rice with a low globulin content and which has a molecular weight of 12,000 to 30,000 is substantially removed, characterized in that rice with a low globulin content is treated with water or an aqueous salt solution. Method. 3. A processed rice food product obtained by using a rice preparation from which rice having a low globulin content and having a protein of a molecular weight of 12,000 to 30,000 is substantially removed. 4. The rice preparation according to claim 1, wherein the rice having a low globulin content is rice having a globulin content in the protein contained in the rice of 10% or less. 5. The method for producing a rice preparation according to claim 2, wherein the rice having a low globulin content is rice having a globulin content in the protein contained in the rice of 10% or less. 6. The processed rice food according to claim 3, wherein the rice having a low globulin content is rice having a globulin content in the protein contained in the rice of 10% or less.