JP4772912B1 - Method for producing bleached processed starch - Google Patents

Abstract

[Problem] To provide a process for producing a modified starch capable of obtaining a sufficient bleaching effect in a modified starch subjected to a chemical processing without changing the properties of the starch.
A method for producing bleached processed starch for food, wherein the starch is reacted with hypochlorous acid or a salt thereof, and then processed to obtain processed starch for food. The manufacturing method in which the processing for obtaining is one or more types of processing selected from the group consisting of hydroxypropylation, phosphoric acid crosslinking, and acetylation using vinyl acetate monomer.
[Selection figure] None

Description

  The present invention relates to a method for producing bleached processed starch, and more particularly to a method for producing processed starch for foods bleached with hypochlorous acid.

  Starch is a grinding process in which raw materials such as corn, potato and cassava are roughly crushed in an aqueous solution, a sieving process to remove fibers such as hulls, a process in which a suspension containing starch and protein is separated by the difference in specific gravity between the two, Processed starch is produced by chemical processing, washing / dehydration, and drying. By this method, the starch purity can be increased to about 99%. However, a trace amount of protein remains in the obtained starch. For example, in the case of corn starch, about 0.3% of protein remains, and it is difficult to further refine starch by the above method. So far, a method of adding sodium hypochlorite to a starch suspension to oxidize and separate proteins is known, and starch obtained by such a method is called bleached starch.

  By the way, processed starch is starch that has been processed to change the structure and properties of starch, and is used in the food industry and various other industries. One of the most representative processed starches is oxidized starch processed using sodium hypochlorite. Oxidized starch is obtained by treating starch with hypochlorous acid, bleaching the starch, and changing the properties of the starch by introducing carboxyl groups (Ministry of Health, Labor and Welfare, Food Safety No. 1001001 (2008)). October 1 of the year)). Oxidized starch has a low viscosity and is mainly used in the paper industry.

  On the other hand, starch that has been bleached with an oxidizing agent without changing the structure of the starch is called bleached starch and is used as food. That is, bleached starch is obtained by adjusting the color tone of starch by treating starch with an oxidizing agent, basically oxidizing other pigment components without chemically modifying the starch ( No. 1001001 from the Ministry of Health, Labor and Welfare (October 1, 2008)). One example is the aforementioned bleached starch obtained by adding sodium hypochlorite to the starch suspension to oxidize and separate the protein.

  Here, according to the Ministry of Health, Labor and Welfare Food Safety No. 1001001 (October 1, 2008), among the starches bleached using sodium hypochlorite, the carboxyl group was tested in the purity test of oxidized starch. Even if the content exceeds 0.1% and the carboxyl group content is 0.1% or less, the result of the confirmation test of the carboxyl group of the oxidized starch is positive or false positive and occurs in the starch properties such as viscosity. If it is not possible to reasonably explain that the change is not due to oxidation, the chemical is judged to have been chemically treated to change the properties of the starch and is not treated as “bleached starch”. It is supposed to be handled as. In addition, according to the Ministry of Health, Labor and Welfare Food Safety No. 1001001 (October 1, 2008), other chemical modifications that are allowed to be combined with oxidation in processed starch for food use acetic anhydride. Only acetylation.

  From this, it is judged that the starch has been sufficiently bleached using hypochlorous acid, and that the properties of the starch have been changed, and further, the chemical processing has been performed twice. It is judged and cannot be used as processed starch for food. That is, in the case of providing a processed starch for food that has been subjected to a desired chemical processing treatment, a sufficient bleaching treatment with hypochlorous acid cannot be performed. Therefore, processed starch for foods that has been subjected to chemical processing needs to achieve a sufficient bleaching effect without changing the properties of the starch.

  Patent Document 1 and Patent Document 2 disclose a method for producing a highly viscous starch by adding a small amount of sodium hypochlorite to starch under specific conditions.

  Patent Document 3 is excellent by adding a large amount of sodium hypochlorite to starch and subjecting it to an oxidation treatment and then adding a small amount of sodium hypochlorite to bleach the starch. A method for producing starch having high viscosity stability is disclosed.

  Patent Document 4 discloses a method for producing starch having a low residual chlorine odor and a high thickening effect by adjusting the pH of the starch suspension and then adding sodium hypochlorite for reaction. ing.

Japanese Patent Laid-Open No. 10-53601 Japanese Patent Publication No. 43-15400 Special Table 2002-521530 gazette JP 2009-73869 A

  However, none of the documents discloses a modified starch that has a satisfactory bleaching effect and is chemically processed.

  The present invention provides a method for producing a processed starch capable of obtaining a sufficient bleaching effect without changing the properties of the starch in the method for producing a processed starch that has been processed to obtain a processed starch for food. The purpose is to do.

  ADVANTAGE OF THE INVENTION According to this invention, after making starch react with hypochlorous acid or its salt, the manufacturing method of the bleached food processed starch which performs the process for obtaining processed food starch is provided. In this production method, the processing for obtaining the processed starch for food is one or more selected from the group consisting of hydroxypropylation, phosphoric acid crosslinking, and acetylation using a vinyl acetate monomer. It is assumed that the processing.

  The processed starch for foods obtained by the production method according to the present invention has a high whiteness that has not existed before. Therefore, the production method according to the present invention can be used for the production of foods that require high whiteness, can reduce the amount of chemicals used for bleaching treatment, and can reduce the chlorine odor derived from the effective chlorine concentration. Is advantageous.

Detailed description of the invention

  Any starch can be used as a starting material in the production method according to the present invention as long as it is a starch for food use. Examples of starch for food use include corn starch, high amylose corn starch, waxy corn starch, sago starch, mung bean starch, wheat starch, rice starch, potato starch, sweet potato starch, and tapioca starch, preferably corn starch, waxy corn starch, Potato starch, tapioca starch, sago starch and sweet potato starch.

  In the production method according to the present invention, untreated starch is treated with hypochlorous acid or a salt thereof. Examples of hypochlorous acid salts include sodium hypochlorite, potassium hypochlorite, and calcium hypochlorite.

  The reaction between starch and hypochlorous acid or a salt thereof is carried out to such an extent that the structure and properties of the starch are not changed so that it is not determined that the starch is processed. Specifically, the carboxyl group content in the starch obtained by reacting with hypochlorous acid or a salt thereof is less than 0.1% by mass, and the starch is negative in the carboxyl group confirmation test. It is possible to react starch with hypochlorite or a salt thereof.

  The content of carboxyl groups introduced into starch by treatment with hypochlorous acid or a salt thereof can be quantified according to a conventional method, for example, carboxyl groups of acetylated oxidized starch described in Ministry of Health, Labor and Welfare Notification No. 485. According to the purity test method.

  Moreover, the confirmation test of the carboxyl group introduce | transduced in starch can be implemented according to the method of the confirmation test of the carboxyl group of the acetylation oxidation starch described in Ministry of Health, Labor and Welfare Notification No. 485, for example.

  In the production method according to the present invention, a starch suspension obtained by suspending starch in water can be used in the reaction system, and the starch concentration of the starch suspension is 20 to 45% by mass in terms of dry starch mass, preferably 36-43 mass%. Hypochlorous acid or a salt thereof can be added to the starch suspension so that the effective chlorine concentration relative to the dry starch mass is 200 to 5500 ppm, preferably 500 to 3000 ppm. In this case, the reaction time and reaction temperature of starch and hypochlorous acid are 5 to 90 minutes (preferably 10 to 60 minutes), 20 to 55 ° C. (preferably 28 to 55 minutes), respectively, from the viewpoint of reaction efficiency. 35 ° C.). The pH of the starch suspension can be set to 3.0 to 11.5 (preferably 4.0 to 10.5) from the viewpoint of reaction efficiency.

  In the production method according to the present invention, the residual chlorine removal treatment may be performed after the treatment with hypochlorous acid or a salt thereof. Here, residual chlorine removal treatment means that a reducing agent such as sodium bisulfite, sodium sulfite, sodium pyrosulfite, or sodium ascorbate is added to the starch suspension during the reaction in order to terminate the reaction with sodium hypochlorite. It means adding. The reducing agent may be either solid or solution. Moreover, the addition amount of a reducing agent can be suitably adjusted according to the addition amount of hypochlorous acid, and the residual chlorine amount which remains.

  The amount of residual chlorine can be confirmed by the KI check method. The KI check method can be implemented as follows. That is, a few drops of 1N sulfuric acid is added to the filter paper, and then a few drops of the starch suspension are added to the filter paper to adjust. When a few drops of 10% potassium iodide solution are added to the solution and discoloration is observed, it means that chlorine remains. When no discoloration was observed, chlorine did not remain, meaning that the residual chlorine removal process was completely performed.

  In the production method according to the present invention, starch is treated with hypochlorous acid or a salt thereof, and then processed to obtain a processed starch for food. The starch treated with hypochlorous acid or a salt thereof may be subjected to processing as it is, or may be subjected to processing after being once dried and resuspended in water.

  Various processing is generally known as processing for obtaining processed starch for food, and typically includes chemical processing for modifying the physical properties and properties of starch. The processing used in the present invention is a chemical processing that exhibits a high reaction rate at pH 9.5 to 11.5. Specifically, hydroxypropylation treatment, phosphoric acid crosslinking treatment, and vinyl acetate monomer were used. It is selected from the group consisting of acetylation treatment. Each of these processing treatments may be performed alone or in combination of two or more processing treatments. These processings are performed using the necessary reagents, ie, hydroxypropylating agent, phosphoric acid cross-linking agent, or vinyl acetate monomer. Moreover, these processing treatments are preferably performed under conditions of pH 9.5 to 11.5. Other specific conditions can be appropriately set by those skilled in the art.

  In the present invention, when chemical processing is performed, physical processing may be additionally performed as necessary. Examples of the physical processing treatment include pregelatinization, wet heat treatment, fat and oil processing, enzyme treatment, acid treatment, alkali treatment, hot water treatment, ball mill treatment, and high pressure treatment.

  The processed starch for foods obtained by the production method according to the present invention can be used in a wide variety of foods such as Japanese and Western confectionery, sauces, sauces, dressings, fillings, fishery / livestock pasteurized foods, and noodles. The processed starch for food obtained by the production method according to the present invention can also be used as an additive for pharmaceutical preparations. That is, in the present invention, “processed starch for food” is used in the meaning including not only foods but also usage modes in pharmaceuticals.

  The processed starch for food obtained by the production method according to the present invention has high whiteness. Accordingly, the production method according to the present invention includes various prepared foods such as breads, croquettes, mentaka cuts, hamburgers, processed meat products, snack confectionery, soups, beverages, Japanese confectionery, western confectionery, sauces, sauces, noodles, marine products and livestock products. It can be used in the manufacture of foods and pharmaceuticals that require high whiteness, such as tablets and tablets, and the amount of chemicals used for bleaching can be reduced to reduce manufacturing costs. Chlorine odor derived from effective chlorine concentration This is advantageous in terms of reducing.

  The present invention will be specifically described based on the following examples, but the present invention is not limited to these examples.

Example 1-1
Water was added to 300 g of untreated tapioca starch (whiteness 80.2) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Subsequently, after adding an alkali agent and adjusting to pH 10, 16.5g of vinyl acetate monomers were added and acetylation reaction was performed for 30 minutes. Thereafter, hydrochloric acid was added to adjust the pH to acidic, thereby terminating the acetylation reaction. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

  The effective chlorine of sodium hypochlorite is quantified by the following method. About 10 g of sodium hypochlorite sample is precisely weighed and transferred to a 200 ml volumetric flask, and then distilled water is added to make a 200 ml sample solution. Take 10 ml of this sample solution in an Erlenmeyer flask with a 200 ml stopper, add 20 ml of 10% potassium iodide solution and 20 ml of 30% sulfuric acid, and mix. This is left to stand in the dark for 5 minutes, and then titrated with 0.05N sodium thiosulfate until colorless. In the blank test, the same operation is performed using 10 ml of distilled water as the sample solution. Effective chlorine is calculated using the following formula.

  The KI check is a simple detection method of effective chlorine performed by the following method. Add a few drops of 1N sulfuric acid to the filter paper and add a few drops of starch suspension on top of it to acclimate. A few drops of 10% potassium iodide solution is added to the solution, and when discoloration is observed, it is determined that effective chlorine remains. On the other hand, when no discoloration is observed, it is determined that no effective chlorine remains.

Example 1-2
The amount of sodium hypochlorite added was 5.54 g (2400 ppm as effective chlorine based on the amount of starch dry substance), and other operations were performed in the same manner as in Example 1-1 to obtain starch samples.

Example 1-3
The raw material starch was untreated waxy corn starch (whiteness 82.0), and other operations were performed in the same manner as in Example 1-1 to obtain starch samples.

Example 1-4
Water was added to 300 g of untreated tapioca starch (whiteness 80.2) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, 1.5 g of pH buffer and an alkali agent were added to adjust the pH to 11, and then 0.36 g of sodium trimetaphosphate was added to carry out a phosphoric acid crosslinking reaction for 60 minutes. Thereafter, hydrochloric acid was added to adjust the pH to acidic, thereby terminating the phosphoric acid crosslinking reaction. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Example 1-5
Water was added to 300 g of untreated waxy corn starch (whiteness 82.0) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Subsequently, 6.0 g of a pH buffer and an alkali agent were added to adjust the pH to 11, and then 21.0 g of propylene oxide was added to carry out a hydroxypropylation reaction for 18 hours. Thereafter, hydrochloric acid was added to adjust the pH to acidic, thereby terminating the hydroxypropylation reaction. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 1-1
Addition and reaction of sodium hypochlorite and sodium pyrosulfite were not performed, and other operations were performed in the same manner as in Example 1-1 to obtain starch samples.

Comparative Example 1-2
Addition and reaction of sodium hypochlorite and sodium pyrosulfite were not performed, and other operations were performed in the same manner as in Example 1-3 to obtain a starch sample.

Comparative Example 1-3
Addition and reaction of sodium hypochlorite and sodium pyrosulfite were not performed, and other operations were performed in the same manner as in Example 1-4 to obtain starch samples.

Comparative Example 1-4
Addition and reaction of sodium hypochlorite and sodium pyrosulfite were not performed, and other operations were performed in the same manner as in Example 1-5 to obtain starch samples.

Comparative Example 2-1
Water was added to 300 g of untreated tapioca starch (whiteness 80.2) to prepare a starch suspension having a solid content of 40 (w / w)%. Subsequently, after adding an alkali agent and adjusting to pH 10, 16.5g of vinyl acetate monomers were added and acetylation reaction was performed for 30 minutes. Thereafter, hydrochloric acid was added to adjust the pH to acidic, thereby terminating the acetylation reaction. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added, and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 2-2
The amount of sodium hypochlorite added was 5.54 g (2400 ppm as effective chlorine with respect to the amount of dry substance of starch), and other operations were performed in the same manner as in Comparative Example 2-1, to obtain a starch sample.

Comparative Example 2-3
An untreated waxy corn starch (whiteness 82.0) was used, and other operations were performed in the same manner as in Comparative Example 2-1, to obtain a starch sample.

Comparative Example 2-4
Water was added to 300 g of untreated tapioca starch (whiteness 80.2) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, 1.5 g of pH buffer and an alkali agent were added to adjust the pH to 11, and then 0.36 g of sodium trimetaphosphate was added to carry out a phosphoric acid crosslinking reaction for 60 minutes. Thereafter, hydrochloric acid was added to adjust the pH to acidic, thereby terminating the phosphoric acid crosslinking reaction. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 2-5
Water was added to 300 g of untreated waxy corn starch (whiteness 82.0) to prepare a starch suspension having a solid content of 40 (w / w)%. Subsequently, 6.0 g of a pH buffer and an alkali agent were added to adjust the pH to 11, and then 21.0 g of propylene oxide was added to carry out a hydroxypropylation reaction for 18 hours. Thereafter, hydrochloric acid was added to adjust the pH to acidic, thereby terminating the hydroxypropylation reaction. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 3-1
Water was added to 300 g of untreated tapioca starch (whiteness 80.2) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, an alkali agent was added to adjust the pH to 8.5, and then 24 g of acetic anhydride was added over 180 minutes, and an alkali agent was appropriately added during that time to maintain pH 8.5 to carry out an acetylation reaction. Thereafter, hydrochloric acid was added to adjust the pH to acidic, thereby terminating the acetylation reaction. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 3-2
Water was added to 300 g of untreated tapioca starch (whiteness 80.2) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, an alkali agent was added to adjust the pH to 8.5, and then 24 g of acetic anhydride was added over 180 minutes, and an alkali agent was appropriately added during that time to maintain pH 8.5 to carry out an acetylation reaction. Thereafter, hydrochloric acid was added to adjust the pH to acidic, thereby terminating the acetylation reaction. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 4-1
Water was added to 300 g of untreated waxy corn starch (whiteness 82.0) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, an alkaline agent was added to adjust the pH to 8.5, and then a solution in which 0.36 g of adipic acid was completely dissolved in 15 g of acetic anhydride was added over 120 minutes. The acetylated adipic acid crosslinking reaction was conducted while maintaining 5. Then, the acetylated adipic acid crosslinking reaction was completed by adjusting the pH to acidic by adding hydrochloric acid. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 4-2
Water was added to 300 g of untreated waxy corn starch (whiteness 82.0) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, an alkaline agent was added to adjust the pH to 8.5, and then a solution in which 0.36 g of adipic acid was completely dissolved in 15 g of acetic anhydride was added over 120 minutes. The acetylated adipic acid crosslinking reaction was conducted while maintaining 5. Then, the acetylated adipic acid crosslinking reaction was completed by adjusting the pH to acidic by adding hydrochloric acid. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 5-1
Water was added to 300 g of untreated waxy corn starch (whiteness 82.0) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, an alkaline agent was added to adjust the pH to 9.0, and then 6 g of octenyl succinic anhydride was added over 60 minutes, and an alkenyl succinic acid reaction was performed while maintaining the pH at 9.0 by appropriately adding an alkaline agent in the meantime. . Then, the octenyl succinic acid reaction was complete | finished by adding hydrochloric acid and adjusting pH to acidity. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Comparative Example 5-2
Water was added to 300 g of untreated waxy corn starch (whiteness 82.0) to prepare a starch suspension having a solid content of 40 (w / w)%. Next, an alkaline agent was added to adjust the pH to 9.0, and then 6 g of octenyl succinic anhydride was added over 60 minutes, and an alkenyl succinic acid reaction was performed while maintaining the pH at 9.0 by appropriately adding an alkaline agent in the meantime. . Then, the octenyl succinic acid reaction was complete | finished by adding hydrochloric acid and adjusting pH to acidity. Next, 2.77 g of sodium hypochlorite (1200 ppm as effective chlorine with respect to the amount of dry substance of starch) was added and bleaching was performed for 30 minutes. Thereafter, the bleaching treatment was completed by adding sodium pyrosulfite until no effective chlorine was detected from the starch suspension in the KI check. Next, this starch suspension was washed twice with 5 times the amount of water, and the resulting starch cake was dried at 40 ° C. for 7 hours to adjust the water content to 15% or less. This was pulverized with a mixer and passed through 50 mesh to obtain a starch sample.

Test Example 1: A color difference meter SE2000 type (manufactured by Nippon Denshoku Industries Co., Ltd.) is used for measurement of whiteness . The measurement method is set to reflection, and standard alignment is performed with a standard white plate SE-15723 (X: 95.29, Y: 93.42, Z: 112.80). Next, the color difference of a glass cell with a diameter of 30 mm filled with a starch sample without gaps is measured five times, and the average value of WB obtained by the five measurements is defined as whiteness.

Test Example 2: Measurement of carboxyl group content The carboxyl group content is quantified by the following method. After adding 50 ml of 0.1N hydrochloric acid to a starch sample having a dry substance amount of 5.0 g, stirring for 30 minutes, suction filtration is performed using a glass filter having a pore size of 10 to 16 μm, and distilled water is used until the filtrate does not exhibit chloride reaction. Continue cleaning with. Chloride reaction can be confirmed by adding a 0.1N silver nitrate solution to the filtrate. If the filtrate becomes cloudy, a chloride reaction has occurred. The residue is suspended in 300 ml of water, heated on a water bath with stirring to gel, and further heated for 15 minutes, then 3 drops of phenolphthalein indicator are added and immediately colored with 0.1N sodium hydroxide solution. Titration quickly. In the blank test, 50 ml of distilled water is added to a starch sample having a dry substance amount of 5.0 g, stirred for 30 minutes, suction filtered using a glass filter having a pore size of 10 to 16 μm, and washed with 200 ml of distilled water. The residue is suspended in 300 ml of distilled water, heated on a water bath with stirring to gel, and further heated for 15 minutes. Then, 3 drops of phenolphthalein indicator is added and immediately colored with 0.1N sodium hydroxide solution. Titrate quickly until The carboxyl group content is calculated using the following formula.

Test Example 3: Confirmation Test for Carboxyl Group 0.5 g of a starch sample is suspended in 25 ml of 1% methylene blue solution, stirred occasionally for 5 to 10 minutes, and then the supernatant is decanted and the precipitate is thoroughly washed with water. Part of the resulting precipitate is collected and observed with a microscope. In microscopic observation, the case where dark blue coloration is observed in starch granules is positive, and the case where dark blue coloration is not observed is negative. In addition, if it is determined that it is difficult to distinguish between positive and negative, a false positive is assumed.

Test Example 4: Measurement of amylogram The gelatinization property of starch slurry prepared to 6% in terms of anhydride was measured using an amylograph (measurement conditions: 95% at 1.5 ° C./min after starting measurement at 30 ° C. The temperature was raised to 0 ° C., and then maintained at 95 ° C. for 30 minutes). From the amylogram measurement result, the viscosity at 95 ° C. and 0 minutes was read, and this was taken as the amylo viscosity. Since the crosslinking degree of phosphoric acid crosslinking tends to be higher as the amylo viscosity is lower, it was used as an index of the crosslinking degree (the lower the amylo viscosity, the higher the crosslinking degree).

  The results of Test Examples 1 to 4 are shown in the following table.

  As is clear from the above results, the whiteness (Examples 1-1 to 1-5) when the treatment with hypochlorous acid was carried out before the processing was performed when the treatment with hypochlorous acid was not carried out. Whiteness (Comparative Examples 1-1 to 1-4) and whiteness (Comparative Examples 2-1 to 2-5) when the treatment with hypochlorous acid was carried out after the processing was significantly higher . Further, as processing, acetylation with VAM at pH 10, phosphoric acid cross-linking at pH 11 and hydroxypropylation at pH 11 (Examples 1-1 to 1-5) are based on AA at pH 8.5. Acetylation (Comparative Examples 3-1 and 3-2), acetylated adipic acid bridge at pH 8.5 (Comparative Examples 4-1 and 4-2), octenyl succinic acid reaction at pH 9.0 (Comparative Examples 5-1 and 5) -2) was significantly higher than the whiteness in the case of carrying out. Furthermore, the amyloviscosity (Example 1-4) in the case of carrying out phosphoric acid crosslinking after the treatment with hypochlorous acid is the amyloviscosity in the case where phosphoric acid crosslinking is carried out without carrying out the treatment with hypochlorous acid ( It was significantly lower than the comparative example 1-3) and the amylo viscosity (comparative example 2-4) when phosphoric acid crosslinking was carried out before the treatment with hypochlorous acid. Therefore, it was shown that when the treatment with hypochlorous acid was carried out before the phosphoric acid crosslinking treatment, the swelling of the starch granules was suppressed and the reaction rate (crosslinking degree) of phosphoric acid crosslinking was improved.

  When chemical processing is applied to starch, the reaction system may be adjusted to be alkaline in order to increase the reactivity of the processing reagents. However, even after neutralization, the whiteness of the starch does not return to the original value, and the whiteness shows a low value. However, in foods and pharmaceuticals where high whiteness is required for starch, starch with such reduced whiteness is not desirable, and preferably starch with a whiteness of 90 or more, more preferably with a whiteness of 92 or more is stable. Need to supply. The processed starch produced by the method according to the present invention satisfies such high whiteness, and the production method according to the present invention is useful for the production of processed starch used in foods and pharmaceuticals that require high whiteness. .

Claims (5)

A method for producing a bleached processed food starch, comprising: reacting starch with hypochlorous acid or a salt thereof; and performing processing to obtain a processed food starch. carboxyl group content in the resulting starch is reacted is less than 0.1 wt%, and shows a negative confirmation test starch is carboxyl group, processing for obtaining a food modified starch, Processing for obtaining processed starch for foods, which is one or more processing selected from the group consisting of hydroxypropylation, phosphoric acid crosslinking, and acetylation using vinyl acetate monomer The manufacturing method with which a process is performed on the conditions of pH9.5-11.5.   The method according to claim 1, wherein after the starch is reacted with hypochlorous acid or a salt thereof, the residual chlorine is removed before the processing for obtaining the processed starch for food. The manufacturing method of Claim 1 or 2 which adds hypochlorous acid or its salt to starch so that the effective chlorine concentration with respect to starch dry mass may be 200-5500 ppm. The manufacturing method as described in any one of Claims 1-3 whose starch is corn starch, waxy corn starch, potato starch, sago starch, sweet potato starch, or tapioca starch. The processed starch for foodstuffs manufactured by the manufacturing method as described in any one of Claims 1-4 .