Method for producing processed cereal powder

Abstract

This method for producing a processed cereal powder comprises: 1) a pH adjustment step for adding an alkaline agent to a slurry containing a cereal powder and water to adjust the pH of the slurry to 10-12; and 2) a reaction step in which sodium trimetaphosphate is added to the slurry having undergone the pH adjustment step in an amount of 2.5-15% by mass relative to the dry mass of the cereal powder in the slurry, and the mixture is reacted. Prior to the reaction step, at least one swelling regulator selected from the group consisting of sodium chloride, sodium sulfate and potassium chloride may be added to the slurry after the pH adjustment step in an amount of 2.5-20 mass% relative to the dry mass of the grain powder in the slurry.

Description

Technical Field

[0001] The present invention relates to a method for producing processed grain flour useful as a raw material for grain flour-containing foods. Background Art

[0002] In the past, phosphoric acid cross-linked starch was used as a raw material for various processed foods. Phosphate cross-linked starch is produced by a method in which phosphorus oxychloride, phosphoric anhydride, trimetaphosphate, hexametaphosphate, etc. react with starch in an alkaline region. For example, in Patent Document 1, as a method for producing phosphoric acid cross-linked starch, a method having a step of reacting starch with sodium trimetaphosphate at 10 to 45° C. in the presence of calcium salts at pH 8 to 12 is described. In the method for producing phosphoric acid cross-linked starch (digestible starch) described in Patent Document 2, sodium trimetaphosphate is added to a slurry containing starch, calcium salt, and a sodium salt having the effect of inhibiting the swelling of starch. The methods for producing phosphoric acid cross-linked starch described in Patent Documents 1 and 2 both use starch, that is, "pure starch" separated from plants such as wheat, as a raw material.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-211922

[0006] Patent Document 2: Japanese Patent Application Publication No. 2020-66703 Summary of the invention

[0007] In recent years, consumer demands for foods containing cereal flour, such as baked goods, have diversified, and the quality level required for foods containing cereal flour has increased, and new processed cereal flours that can meet such demands have been required.

[0008] An object of the present invention is to provide a processed cereal flour capable of producing a cereal flour-containing food having a good taste.

[0009] The present invention is a method for producing processed grain flour, which comprises the following steps:

[0010] a pH adjustment step of adding an alkali agent to a slurry containing cereal flour and water to adjust the pH of the slurry to 10 to 12; and

[0011] The reaction step is to add 2.5 to 15% by mass of sodium trimetaphosphate relative to the dry mass of the cereal flour in the slurry to the slurry having undergone the pH adjustment step and react the mixture. DETAILED DESCRIPTION

[0012] The processed grain flour as the manufacturing target of the manufacturing method of the present invention is useful as a raw material for grain flour-containing foods. In this specification, "grain flour-containing foods" refers to processed foods using grain flour as a raw material. Grain flour-containing foods are typically manufactured by adding a liquid raw material (e.g., water, milk, egg liquid) to a powder raw material containing grain flour and mixing to prepare a dough (e.g., raw dough, batter), and heating the dough (e.g., baking, frying). Specific examples of grain flour-containing foods include baked foods; fried foods such as tempura batter; Japanese assorted pancakes, takoyaki, spring roll wrappers, and pie dough.

[0013] Examples of baked foods to which the present invention can be applied include breads; cakes; baked snacks such as waffles, cream puffs, and cookies; fried snacks such as donuts, etc. Examples of breads include staple breads (e.g., rolls, white bread, brown bread, French bread, dry bread, hot dog bread, croissants, etc.), seasoned breads, snack breads, steamed buns, etc. Examples of cakes include sponge cakes, butter cakes, cake rolls, hot scones, pies, Baumkuchen, pound cakes, cheese cakes, snack cakes, muffins, cake bars, cookies, pancakes, etc.

[0014] The manufacturing method of processed grain flour of the present invention uses grain flour as a raw material to deteriorate the components such as starch and protein in the grain flour. In particular, the protein in the grain flour is appropriately modified by being supplied to the manufacturing method of the present invention, so the processed grain flour manufactured by the manufacturing method is difficult to retain water, and the thermal conductivity during secondary processing is greatly improved compared with existing products, and the grain flour-containing food using the processed grain flour has a crispy texture with good tooth brittleness. In addition, as a raw material, instead of using a component such as starch that is mixed with other components in the grain flour, the grain flour itself is used, thereby eliminating the need for a process of extracting a desired component from the grain flour, and thus it is possible to seek to reduce the manufacturing cost.

[0015] As the cereal flour, any cereal flour that has been used as a raw material for cereal flour-containing foods can be used without particular limitation, for example, wheat flour such as strong flour, semi-strong flour, medium flour, light flour, and durum wheat flour; barley flour, corn flour, rice flour, sorghum flour, soybean flour, rye flour, oat flour, buckwheat flour, soybean flour, coix seed flour, barley flour, millet flour, etc. can be used alone or in combination of two or more thereof. Among these cereal flours, wheat flour, barley flour, corn flour, rice flour, sorghum flour, and soybean flour, especially wheat flour, have a high affinity with the specific examples of the above-mentioned cereal flour-containing foods, and are therefore preferably used as a raw material for processed starch.

[0016] In the method for producing processed grain flour of the present invention, a slurry containing grain flour and water is prepared, and the slurry is subjected to a predetermined step (pH adjustment step, reaction step). The slurry is typically a suspension in which grain flour particles are mixed in water in a stable state, and has fluidity at normal temperature and pressure (atmospheric temperature 20° C., 1 atmosphere). The slurry can be prepared according to a conventional method.

[0017] The content of the grain flour in the above-mentioned slurry is not particularly limited. From the viewpoints of improving the operability of the slurry and improving the reaction efficiency of the phosphoric acid cross-linking reaction in the reaction step described later, it is preferably 20 to 50% by mass, more preferably 30 to 40% by mass relative to the gross mass of the slurry. The content of the grain flour in the slurry is typically the same as the content of the solid component in the slurry.

[0018] In the method for producing processed grain flour of the present invention, an alkali agent is added to the slurry to adjust the pH of the slurry to 10 to 12, preferably 10.5 to 11.5, and more preferably 11 to 11.5 (pH adjustment step). When the pH of the slurry is less than 10, the phosphoric acid cross-linking reaction in the reaction step of the next step may not proceed sufficiently, and when the pH exceeds 12, the starch inherent in the grain flour in the slurry may gelatinize. In short, the prescribed effect of the present invention (the provision of processed grain flour capable of producing grain flour-containing food with good taste) may not be exerted.

[0019] As the alkali agent, any alkali agent conventionally used in the phosphoric acid cross-linking reaction of starch can be used without particular limitation, and examples thereof include sodium hydroxide, calcium hydroxide, sodium carbonate, and the like, and these can be used alone or in combination of two or more.

[0020] In the method for producing processed flour of the present invention, 2.5 to 15% by mass of sodium trimetaphosphate relative to the dry mass of the flour in the slurry is added to the slurry after the pH adjustment step, and the mixture is reacted (reaction step). Sodium trimetaphosphate functions as a phosphoric acid crosslinking agent for the starch inherent in the flour in the slurry, and thus acts on the hydroxyl groups of the sugar chains in the starch to phosphorylate and crosslink the starch.

[0021] In the past, phosphorus oxychloride and the like have been used as phosphate crosslinking agents for starch in addition to sodium trimetaphosphate. However, the use of sodium trimetaphosphate is advantageous in stabilizing the phosphate crosslinking reaction, thereby enabling the manufacturing target product (processed grain flour) of the present invention to be manufactured with high purity and high efficiency.

[0022] In the above reaction step, if the amount of sodium trimetaphosphate added to the above slurry is less than 2.5% by mass relative to the dry mass of the grain flour in the slurry, the phosphoric acid cross-linking reaction of the starch inherent in the grain flour may become insufficient, and if it exceeds 15% by mass, the reaction efficiency may be reduced and the characteristics (cross-linking degree of starch) consistent with the amount added may not be obtained. The amount of sodium trimetaphosphate added to the above slurry is preferably 3.5 to 12.5% ​​by mass, more preferably 5 to 10% by mass relative to the dry mass of the grain flour in the slurry.

[0023] From the viewpoint of more reliably imparting the desired properties to the processed grain flour, the reaction time of the above-mentioned reaction step is preferably 3 to 24 hours, more preferably 6 to 24 hours. When the above-mentioned reaction time is too short, it is likely to be difficult to impart the desired properties to the processed grain flour, and when the reaction time is too long, the properties of the processed grain flour that match them cannot be obtained, which is also related to the rise in manufacturing costs.

[0024] In the reaction step, from the viewpoint of improving the reaction efficiency of the phosphoric acid cross-linking reaction of starch in the grain flour in the slurry, the temperature of the slurry is preferably 25 to 45° C., more preferably 30 to 40° C. That is, during the reaction time of the reaction step, the temperature of the slurry is preferably maintained in the above range.

[0025] Furthermore, in the reaction step, the slurry is preferably stirred during the reaction time from the viewpoint of improving the reaction efficiency.

[0026] In the present invention, "reaction time of the reaction process" refers to the period from the time when sodium trimetaphosphate is initially added to the above-mentioned slurry whose pH is adjusted to the range of 10 to 12 to the time when the acidic agent is initially added to neutralize the slurry. In the manufacturing method of the present invention, sodium trimetaphosphate can be added to the above-mentioned slurry in multiple times. In this case, the initial addition time of sodium trimetaphosphate is the beginning of the reaction time of the above-mentioned reaction process. The same applies to the above-mentioned acidic agent. As the above-mentioned acidic agent, the acidic agent previously used in the phosphate cross-linking reaction of starch can be used without particular limitation, for example, hydrochloric acid can be mentioned. In the neutralization of the above-mentioned slurry used to terminate the above-mentioned reaction process, the pH of the slurry is preferably adjusted to 5 to 7.

[0027] In the manufacturing method of the present invention, one or more swelling regulators selected from the group consisting of sodium chloride, sodium sulfate and potassium chloride may be added to the slurry after the pH adjustment step before the reaction step. This can further improve the effect of processing the grain flour on improving the taste of the grain flour-containing food (e.g., the goodness of tooth crispness).

[0028] The amount of the swelling control agent added to the slurry is preferably 2.5 to 20% by mass, more preferably 5 to 15% by mass, based on the dry mass of the cereal flour in the slurry.

[0029] When the swelling regulator is added to the slurry after the pH adjustment step, a magnesium salt may be added together with the swelling regulator. This can further improve the effect of processing the flour on improving the texture of the flour-containing food (for example, the goodness of the tooth crispness).

[0030] The amount of the magnesium salt added to the slurry is preferably 0.01 to 1% by mass, more preferably 0.03 to 0.8% by mass, relative to the dry mass of the grain flour in the slurry.

[0031] As the above-mentioned magnesium salt, for example, magnesium chloride, magnesium sulfate, magnesium carbonate, magnesium oxide, magnesium glutamate, and magnesium silicate can be mentioned, and one of them can be used alone or in combination of two or more. Among these magnesium salts, magnesium chloride, magnesium sulfate, and magnesium carbonate are particularly preferred.

[0032] After the reaction step is completed, water is added to the neutralized slurry and stirred, and the reactant in the slurry is washed and then dried to remove water, thereby obtaining the target processed grain flour. The processed grain flour obtained in this way can also be crushed and made into powder as needed.

[0033] For the processed flour produced by the manufacturing method of the present invention, from the viewpoint of appropriately improving the mouthfeel (goodness of tooth brittleness) of the flour-containing food using it, the phosphorus content is preferably 0.02 to 0.4 mass %, particularly preferably 0.05 to 0.3 mass %. The phosphorus content of the processed flour can be measured by a known atomic absorption spectrometry. By implementing the manufacturing method of the present invention under the above conditions, the phosphorus content of the processed flour finally obtained can be adjusted to the above preferred range.

[0034] For the processed flour produced by the production method of the present invention, from the viewpoint of appropriately suppressing the gelatinization of the starch in the processed flour, the RVA final viscosity measured by the following method using a rapid viscosity analyzer (rapid viscosity measuring device; abbreviated as "RVA") is preferably 50 to 10000 mPa·S, and particularly preferably 500 to 5000 mPa·S. By carrying out the production method of the present invention under the above conditions, the RVA final viscosity of the processed flour finally obtained can be adjusted to the above preferred range.

[0035] In the RVA-based viscosity measurement of processed cereal flour, the viscosity is measured while accompanying the temperature change (heating and then cooling) of a suspension prepared by suspending the processed cereal flour in water. Generally, in the RVA measurement of starch, at the initial stage of the start of heating, no large change in viscosity is found in the suspension, but the starch granules swell from a certain temperature, so the viscosity rises sharply to reach the maximum (RVA peak viscosity), and then the starch granules collapse and the viscosity decreases. When the suspension is further cooled, the starch recrystallizes, so the viscosity rises again and finally reaches a stable state (RVA final viscosity).

[0036] <Method for Measuring RVA Final Viscosity>

[0037] Water is added to the object to be measured (processed cereal flour) to prepare a suspension in which the content of the object to be measured is 20% by mass in terms of dry matter, and the viscosity of this suspension is measured using an RVA. As the RVA, for example, "RVA4800" manufactured by PerkinElmer or a measuring device based on it can be used.

[0038] Specifically, the suspension and a paddle (stirrer) are placed in a container for accommodating the object to be measured attached to the RVA, and while rotating the paddle at a rotational speed of 160 rpm / min, the suspension is heated, and then its viscosity is measured while cooling. The temperature (product temperature) of the above suspension is adjusted as follows.

[0039] Temperature adjustment of the suspension: First, it is maintained at 50 °C for 1 minute. Then, it is raised to 95 °C under the condition of increasing the temperature by 12 °C per minute, and maintained at this temperature for 3 minutes (heating period). Then, it is lowered to 50 °C under the condition of decreasing the temperature by 12 °C per minute, and maintained at this temperature for 2 minutes (cooling period).

[0040] Then, a viscosity curve of the above suspension is obtained from the measured values of the above viscosity, and the maximum viscosity of the suspension during the cooling period in this viscosity curve is taken as the RVA final viscosity of the object to be measured (processed cereal flour) in the suspension. It should be noted that the above RVA peak viscosity is the maximum viscosity of the suspension during the heating period in the above viscosity curve.

[0041] Examples

[0042] Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples.

[0043] [Examples 1 to 8, Comparative Examples 1 to 4: Manufacture of Processed Cereal Flour]

[0044] An alkali agent is added to a slurry containing only grain flour and water, the pH of the slurry is adjusted to a specified range, a specified amount of sodium trimetaphosphate is added to the slurry after the pH adjustment, and the slurry is reacted for a specified time to produce processed grain flour. Specifically, the processed grain flour is produced by the following standard method or a method based thereon (e.g., a method in which the amount of reagent used is changed from the standard method). The production conditions such as the composition of the slurry and the reaction conditions are shown in the following Table 1.

[0045] (Standard method)

[0046] 1000 g of water is added to 500 g of grain flour and stirred to prepare a slurry. Then, a sodium hydroxide aqueous solution with a sodium hydroxide concentration of 4% by mass is added to the above slurry, and the pH of the slurry is adjusted to 11 (pH adjustment process). Then, 37.5 g of sodium trimetaphosphate is added to the above slurry at a product temperature of 30°C, and the slurry is stirred while maintaining the product temperature of 30°C (reaction process). As a result, the phosphate cross-linking reaction of the starch inherent in the grain flour in the slurry proceeds. After stirring the slurry for 10 hours, a hydrochloric acid aqueous solution with a hydrochloric acid concentration of 8.5% by mass is added dropwise to the slurry to adjust the pH of the slurry to a neutral region, thereby stopping the phosphate cross-linking reaction. Next, the above slurry is centrifuged at a rotation speed of 3000 rpm for 5 minutes, the supernatant of the slurry is removed, and a specified amount of water is added to the residue of the slurry and stirred. This series of operations was repeated three times to wash the reaction product in the slurry, and then the water content of the reaction product was evaporated and dried. The dried product was pulverized to obtain powder of the target processed grain flour.

[0047] [Examples 9 to 13: Production of Processed Flour Using Swelling Regulator]

[0048] Processed grain flour was produced by the same method as the above-mentioned standard method or a method based thereon, except that a predetermined amount (see Table 2 below) of a swelling regulator was added to the slurry having undergone the above-mentioned pH adjustment step before the above-mentioned reaction step.

[0049] [Examples 14 to 18: Production of Processed Flour Using Swelling Regulator and Magnesium Salt]

[0050] Processed flour was produced by the same method as the above-mentioned standard method or a method based thereon, except that a predetermined amount (see Table 3 below) of magnesium salt was added to the slurry simultaneously with the above-mentioned swelling modifier.

[0051] [Evaluation test]

[0052] Using the processed flour of each of the Examples and Comparative Examples, hot pancakes as a type of flour-containing food (baked food) were produced by the following method.

[0053] In addition, hotcakes were produced in the same manner as the method using the processed flour of each Example and Comparative Example except that unprocessed flour (brinjal or rice flour) was used instead of processed flour, and these hotcakes were used as controls.

[0054] Ten professional panelists were asked to eat the hot pancakes just after production, and the texture (goodness of tooth crunchiness) was rated according to the following evaluation criteria. The rating results (arithmetic mean scores of the ten professional panelists) are shown in Tables 1 to 3 below.

[0055] (Method for making hot pancakes)

[0056] 17 g of the flour (processed flour or unprocessed flour) of the evaluation object, 16.5 g of spelt flour, 15 g of sugar and 1.5 g of baking powder were put into a bowl and mixed to prepare a mixture. Then, 12.5 g of whole egg liquid and 37.5 g of milk as liquid raw materials were added to the mixture, and the mixture was stirred at a speed of 120 rpm for 1 minute by manual stirring using a whisk to prepare a dough. After the dough was allowed to stand for 5 minutes in an environment of normal temperature and pressure, the entire amount of the dough was poured onto a baking net, and after baking at 170°C for 3 minutes, the dough was turned upside down and further baked at 170°C for 3 minutes to obtain the target hot pancake.

[0057] <Evaluation criteria for mouthfeel (goodness of tooth crispness)>

[0058] The texture of the hotcakes of the examples and comparative examples was evaluated based on the texture of the hotcakes of the control example. The hotcakes of the control example were the same as the hotcakes of the examples or comparative examples except that the raw material flour was unprocessed.

[0059] 5 points: The crunchy texture was quite strong compared to the control.

[0060] 4 points: The crispy texture was stronger than that of the control.

[0061] 3 points: The texture was as crispy as that of the control example.

[0062] 2 points: Compared with the control, the chewiness is strong and the crispy texture is weak.

[0063] 1 point: Compared with the control, the texture is quite strong and not crispy.

[0064]

[0065] As shown in Table 1, in each embodiment, the pH of the slurry containing cereal flour and water is adjusted to 10-12, and the amount of sodium trimetaphosphate added to the slurry is in the range of 2.5-15% by mass relative to the dry mass of the cereal flour in the slurry. Therefore, compared with the comparative examples that do not meet this condition, the taste of the hot pancakes is good.

[0066]

[0067]

[0068] Industrial Applicability

[0069] According to the present invention, a processed flour capable of producing a flour-containing food having a good taste is provided. When a flour-containing food is produced using the processed flour produced by the production method of the present invention, since the swelling and gelatinization of starch in the processed flour is appropriately suppressed, a flour-containing food having a good tooth crispness and a crisp taste can be obtained.

Claims

1. A method for producing processed grain flour, comprising the following steps: a pH adjustment step of adding an alkali agent to a slurry containing cereal flour and water to adjust the pH of the slurry to 10 to 12; and The reaction step is to add 2.5 to 15% by mass of sodium trimetaphosphate relative to the dry mass of the cereal flour in the slurry to the slurry having undergone the pH adjustment step and react the mixture.

2. The method for producing processed grain flour according to claim 1, wherein: The cereal flour is one or more selected from wheat flour, barley flour, corn flour, rice flour, sorghum flour and soybean flour.

3. The method for producing processed grain flour according to claim 1 or 2, wherein: The reaction time of the reaction step is 3 to 24 hours.

4. The method for producing processed grain flour according to any one of claims 1 to 3, wherein Prior to the reaction step, a swelling regulator is added to the slurry after the pH adjustment step in an amount of 2.5 to 20% by mass relative to the dry mass of the cereal flour in the slurry. The swelling regulator is at least one selected from the group consisting of sodium chloride, sodium sulfate and potassium chloride.

5. The method for producing processed grain flour according to claim 4, wherein: Prior to the reaction step, 0.01 to 1% by mass of a magnesium salt is added to the slurry that has undergone the pH adjustment step based on the dry mass of the grain flour in the slurry.

6. The method for producing processed grain flour according to claim 5, wherein: The magnesium salt is one or more selected from magnesium chloride, magnesium sulfate and magnesium carbonate.

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