JP2019156882A - Composition containing high amylose starch and cellulose nanofibers - Google Patents

Abstract

To provide a method capable of efficiently suppressing starch aging of a starch-based food.SOLUTION: The present invention provides the followings: a composition comprising (A) component: a starch-based raw material at least containing a starch having an amylose content of 15% by mass or more, and (B) component: cellulose nanofibers; as well as a starch aging inhibitor and a starch-based food additive that both contain the composition; a method for producing the starch-based food, which includes using the composition in place of at least a part of the starch that is a raw material of the starch-based food; and a method for modifying the starch-based food, which uses the composition in place of at least a part of the starch that is the raw material of the starch-based food.SELECTED DRAWING: None

Description

  The present invention relates to a composition comprising high amylose starch and cellulose nanofibers.

  When starch is heated together with moisture, the viscosity increases from a white turbid state, and the state becomes highly transparent. Such a phenomenon of starch is called gelatinization and gives a unique shape and texture to food. Starch is used as a thickener, stabilizer, gelling agent, etc. Widely used in starch-based foods. However, gelatinized starch loses its water-holding power with the passage of time, releases water, becomes insoluble like a gel, and causes an aging phenomenon such as becoming cloudy gradually. As a result, the taste and texture of the food may be significantly reduced, such as becoming hard and dry. Therefore, a method for effectively suppressing starch aging is desired. The cause of aging of starch is considered to be recrystallization and insolubilization of starch molecules dispersed by gelatinization. The aging rate is considered to depend on factors such as temperature, pH, and the molecular structure of starch. Various techniques have been proposed in the past as methods for suppressing starch aging of starch-based foods.

  Patent Document 1 describes that when trehalose is added to a raw material for starchy food, aging of the starchy food can be prevented. Patent Document 2 describes that aging of moss can be prevented by adding β-amylase and trehalose to the moss dough. Patent Document 3 describes that when a baked food is produced by adding cellulose nanofibers and baker's yeast to the dough, the water retention of the baked food is improved.

JP-A-8-242784 JP-A-9-107899 JP 2017-176034 A

  However, since the methods of Patent Documents 1 and 2 use a large amount of trehalose, the sweetness of trehalose may change the original taste and flavor of food. Moreover, in the method of patent document 3, although the water retention of a baking dough improves, the aging suppression of starch is inadequate.

  An object of this invention is to provide the method which can suppress efficiently the aging of the starch of a starch-type foodstuff.

The present invention provides the following [1] to [8].
[1] Component (A): a starch-based raw material containing at least starch having an amylose content of 15% by mass or more, and (B) component: a composition containing cellulose nanofibers.
[2] The composition according to [1], wherein the ratio of the mass of the component (B) to the total mass of the starch contained in the component (A) is 0.1 to 50% by mass.
[3] The composition according to [1] or [2], wherein the component (B) includes chemically modified cellulose nanofibers.
[4] In any one of [1] to [3], the chemically modified cellulose nanofiber is a carboxymethylated cellulose nanofiber having a degree of carboxymethyl substitution per glucose unit of 0.01 to 0.50. The composition as described.
[5] A starch aging inhibitor comprising the composition according to any one of [1] to [4] as an active ingredient.
[6] A starch-based food additive comprising the composition according to any one of [1] to [4] as an active ingredient.
[7] A method for producing a starch-based food, comprising using the composition according to any one of [1] to [4] instead of at least a part of starch as a raw material of the starch-based food.
[8] A method for modifying starch-based foods, wherein the composition according to any one of [1] to [4] is used in place of at least part of starch as a raw material for starch-based foods.

  By adding the composition of the present invention to starch-based foods, it is possible to suppress aging of starch and enhance the storage stability.

  The reason why these effects can be obtained by the present invention is not clear, but in the present invention, the effects of cellulose nanofibers inhibiting the recrystallization of amylose, which is the main cause of starch aging, are affecting. It is guessed.

FIG. 1 is a graph showing the results of RVA measurement in Example 1 and Comparative Example 1. FIG. 2 is a graph showing the results of RVA measurement in Example 2 and Comparative Example 2. FIG. 3 is a graph showing the results of RVA measurement in Comparative Examples 3 and 4.

  The composition of the present invention contains the following components (A) and (B). Thereby, when the composition of this invention is added to a foodstuff, preservability can be improved. For example, it is possible to suppress aging of starch in foods, and to suppress a significant decrease in the original taste and texture of foods, such as the foods becoming hard and dry.

<(1) (A) component: Starch-based raw material>
(A) A component is a starch-type raw material. The starch-based raw material is a raw material containing starch. The starch-based material contains at least starch having an amylose content of 15% by mass or more, preferably 20% by mass or more, and more preferably 22% by mass or more. Thereby, aging of starch can be controlled efficiently. An upper limit is not specifically limited, Usually, it is 50 mass% or less. The amylose content is the ratio (% by mass) of the mass of amylose to the total mass of starch.

  Starch-based raw materials are not particularly limited. For example, rice, corn, wheat, barley, buckwheat, beans (soybean, green beans, green peas), potatoes (potato, sweet potato, taro), tapioca, sago palm, bananas, etc. At least some (so-called cereal grains themselves, or parts thereof (eg, seeds, roots, rhizomes, fruits)) and processed products (eg, powder), and high amylose species (eg, high amylose rice) of these plants. High amylose wheat, high amylose buckwheat) and processed products thereof are preferred, and high amylose rice or rice flour thereof is more preferred. The high amylose species preferably have an amylose content that satisfies the above range. The brands of high amylose rice include, for example, Koshi no Kaori, Mizuhochikara, Momomiman, Hoshinishiki, Kinoshinjiman, Hoshiyutaka, Yumejuiro, Hoshinishiki, Yukihikari and Tosenbo. As long as it is high amylose rice, not only japonica rice but also indica rice or jabonica rice may be used. Indica rice production areas include, for example, Southeast Asia such as Thailand, Vietnam, Laos, Myanmar, Indonesia, Malaysia, and Singapore; South Asia such as India and Bangladesh; South Central China; Caspian Coastal Region; United States of America; It is done. The amount of starch contained in the starch-based raw material varies depending on the type and cannot be specified unconditionally. For example, in the case of rice powder of high amylose rice, it is 90% by mass or more.

<(2) (B) component: cellulose nanofiber>
(B) A component is a cellulose nanofiber. The cellulose nanofiber is a fine fiber of cellulose. Cellulose nanofibers may be either those using unmodified cellulose as a cellulose raw material or those using modified cellulose (for example, chemically modified cellulose) as a raw material. The average fiber diameter of the cellulose nanofiber is usually about 3 to 500 nm, preferably 3 nm or more and 500 nm or less. The average aspect ratio of the cellulose nanofiber is usually 50 or more. The upper limit of the aspect ratio is not particularly limited, but is usually 1000 or less. The average aspect ratio can be calculated by the following formula:
(Formula) Aspect ratio = average fiber length / average fiber diameter

  The average fiber diameter and average fiber length of cellulose nanofibers should be the average of the fiber diameter and fiber length obtained from the observation of each fiber using an atomic force microscope (AFM) or a transmission electron microscope (TEM). Can be obtained respectively. The average fiber length and the average fiber diameter can be adjusted by conditions such as modification treatment (for example, oxidation treatment) and defibration treatment when producing cellulose nanofibers.

  The method for producing cellulose nanofibers is not particularly limited. For example, a cellulose raw material (for example, pulp) is subjected to mechanical force to be refined, and the cellulose raw material is modified by a modification treatment (for example, a chemical modification treatment). A method for fibrillating cellulose (for example, carboxylated cellulose (also called oxidized cellulose), carboxymethylated cellulose, esterified cellulose (for example, chemically modified cellulose such as phosphoesterified cellulose), cationized cellulose, etc.) A method of modifying the defibrated cellulose fiber obtained by defibrating is mentioned.

<(2-1) Cellulose raw material>
The origin of the cellulose raw material (for example, cellulose fiber) is not particularly limited. For example, plants (for example, wood, bamboo, hemp, jute, kenaf, farmland waste, cloth, pulp (coniferous unbleached kraft pulp (NUKP)), Softwood Bleached Kraft Pulp (NBKP), Hardwood Unbleached Kraft Pulp (LUKP), Hardwood Bleached Kraft Pulp (LBKP), Softwood Unbleached Sulfite Pulp (NUSP), Softwood Bleached Sulfite Pulp (NBSP), Thermomechanical Pulp (TMP) , Recycled pulp, waste paper, etc.), animals (for example, ascidians), algae, microorganisms (for example, acetic acid bacteria (Acetobacter)), microbial products, etc. The cellulose raw material used in the present invention is any of these. It may be a combination of two or more types, preferably a plant or Biological cellulose raw material, more preferably a cellulose material of plant origin.

  The number average fiber diameter of the cellulose raw material is not particularly limited, but is about 30 to 60 μm for softwood kraft pulp, which is a general pulp, and about 10 to 30 μm for hardwood kraft pulp. The number average fiber diameter of other pulps that have undergone general refining is about 50 μm. When a cellulose raw material is obtained by purifying a chip or the like having a size of several centimeters, it is preferable to perform a mechanical treatment with a disintegrator such as a refiner or a beater to adjust the number average particle diameter to about 50 μm.

<(2-2) Dispersion>
A dispersion treatment may be performed during at least one of the fibrillation treatment and the modification treatment of the cellulose raw material. The dispersion treatment is a treatment for preparing a dispersion by dispersing a cellulose raw material, defibrated cellulose fiber or modified cellulose in a solvent.

  In the dispersion treatment, a cellulose raw material, defibrated cellulose fiber or modified cellulose is usually dispersed in a solvent. Although a solvent will not be specifically limited if a modified cellulose can be disperse | distributed, For example, water, organic solvents (for example, hydrophilic organic solvents, such as methanol), and those mixed solvents are mentioned. The solvent is preferably water because it is used for food and the cellulose raw material is hydrophilic.

  The solid content concentration of the modified cellulose in the dispersion is usually 0.1% by mass or more, preferably 0.2% by mass or more, more preferably 0.3% by mass or more. Thereby, the liquid quantity with respect to the quantity of a cellulose fiber raw material becomes an appropriate quantity, and is efficient. The upper limit is usually 10% by mass or less, preferably 6% by mass or less. Thereby, fluidity | liquidity can be hold | maintained.

  Prior to the defibrating process or the dispersion process, a preliminary process may be performed as necessary. The pretreatment may be performed using a mixing, stirring, emulsifying, and dispersing device such as a high-speed shear mixer.

<(2-3) Chemically modified cellulose nanofiber>
The component (B) preferably contains chemically modified cellulose nanofibers. Thereby, when a composition is added to food, a better texture can be realized. Moreover, it is preferable that (B) component is a chemically modified cellulose nanofiber. Chemically modified cellulose nanofibers have sufficiently advanced fiber refinement, uniform fiber length and fiber diameter, and can further improve food texture.

  Although the manufacturing method of a chemically modified cellulose nanofiber is not specifically limited, The method of passing through the chemical modification process of a cellulose raw material or a defibrated cellulose fiber is mentioned. The chemical modification treatment is not particularly limited as long as it is a treatment that chemically modifies at least a part of cellulose, and examples thereof include oxidation, etherification, phosphorylation, esterification, and carboxymethylation. Or esterification is preferred, and carboxymethylation is more preferred.

[Carboxymethylation]
Examples of the carboxymethylation method include a method in which a cellulose raw material or a defibrated cellulose fiber is mercerized and then etherified. In the carboxymethylation reaction, a solvent is usually used. Examples of the solvent include water, alcohol (eg, lower alcohol), and mixed solvents thereof. Examples of the lower alcohol include methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, and tertiary butyl alcohol. As for the mixing ratio of the lower alcohol in the mixed solvent, the lower limit is usually 60% by mass or more, and the upper limit is usually 95% by mass or less, preferably 60 to 95% by mass. The amount of the solvent is usually 3 mass times or more with respect to the cellulose raw material or the defibrated cellulose fiber. Moreover, although the upper limit of the quantity of a solvent is not specifically limited, It is 20 mass times or less normally with respect to a cellulose raw material or a defibrated cellulose fiber. Therefore, the amount of the solvent is preferably 3 to 20 times by mass with respect to the cellulose raw material or the defibrated cellulose fiber.

  Mercerization is usually performed by mixing a cellulose raw material or defibrated cellulose fiber and a mercerizing agent. Examples of mercerizing agents include alkali metal hydroxides (eg, sodium hydroxide, potassium hydroxide).

  The lower limit of the amount of mercerizing agent used is usually 0.5 times mol or more per anhydroglucose residue of cellulose raw material or defibrated cellulose fiber. Moreover, an upper limit is 20 times mole or less normally. Therefore, the usage amount of the mercerizing agent is preferably 0.5 to 20 times mol per anhydroglucose residue of the cellulose raw material or defibrated cellulose fiber.

  The lower limit of the mercerization reaction temperature is usually 0 ° C. or higher, preferably 10 ° C. or higher. The upper limit is usually 70 ° C. or lower, preferably 60 ° C. or lower. Accordingly, the reaction temperature for mercerization is usually 0 to 70 ° C, preferably 10 to 60 ° C.

  The lower limit of the mercerization reaction time is usually 15 minutes or longer, preferably 30 minutes or longer. The lower limit is usually 8 hours or less, preferably 7 hours or less. Accordingly, the reaction time for mercerization is usually 15 minutes to 8 hours, preferably 30 minutes to 7 hours.

  The etherification reaction is usually performed by adding a carboxymethylating agent to the reaction system after mercerization. Examples of the carboxymethylating agent include sodium monochloroacetate.

  The lower limit of the addition amount of the carboxymethylating agent is usually 0.05 times mol or more per glucose residue of the cellulose raw material or defibrated cellulose fiber. The upper limit is usually 10.0 times mol or less. Therefore, the addition amount of the carboxymethylating agent is usually 0.05 to 10.0 times mole per glucose residue of the cellulose raw material or defibrated cellulose fiber. The lower limit of the etherification reaction temperature is usually 30 ° C. or higher, preferably 40 ° C. or higher. The upper limit is usually 90 ° C. or lower, preferably 80 ° C. or lower. Accordingly, the reaction temperature for etherification is usually 30 to 90 ° C, preferably 40 to 80 ° C.

  The lower limit of the etherification reaction time is usually 30 minutes or longer, preferably 1 hour or longer. The upper limit is usually 10 hours or less, preferably 4 hours or less. Therefore, the reaction time for etherification is usually 30 minutes to 10 hours, preferably 1 hour to 4 hours.

  The degree of carboxymethyl substitution per glucose unit in the carboxymethylated cellulose or carboxymethylated cellulose nanofiber is preferably 0.01 or more, more preferably 0.10 or more, and further preferably 0.15 or more. The upper limit is preferably 0.50 or less, more preferably 0.40 or less, and still more preferably 0.35 or less. Therefore, the degree of carboxymethyl substitution is preferably 0.01 to 0.50, more preferably 0.10 to 0.40, and still more preferably 0.15 to 0.35.

Examples of the method for measuring the degree of carboxymethyl substitution per glucose unit include the following methods: 1) Weigh accurately about 2.0 g of carboxymethylated cellulose fiber or carboxymethylated cellulose nanofiber (absolutely dry). 2) Add 100 mL of special grade concentrated nitric acid to 1000 mL of methanol, add 100 mL of nitric acid methanol solution and shake for 3 hours to carboxylate carboxymethylcellulose salt (carboxymethylated cellulose) Carboxymethylated cellulose having a group (hereinafter also referred to as “acid-type carboxymethylated cellulose”); 3) 1.5-2.0 g of acid-type carboxymethylated cellulose (absolutely dry) is accurately weighed, and 300 mL Place in a conical flask with stopper; 4) 80% Wet the acid type carboxymethyl cellulose in Nord 15 mL, NaOH of 0.1N was added 100 mL, shaking for vibration at room temperature for 3 hours; as 5) indicator, using phenolphthalein, of 0.1N H ₂ SO ₄ Excess NaOH is back titrated with; 6) The degree of carboxymethyl substitution (DS) is calculated by the following formula:
A = [(100 × F ′ − (0.1N H ₂ SO ₄ ) (mL) × F) × 0.1] / (absolute dry mass of acid-type carboxymethylated cellulose (g))
DS = 0.162 × A / (1-0.058 × A)
A: 1N NaOH amount (mL) required for neutralizing 1 g of acid-type carboxymethylated cellulose
F: Factor of 0.1N H ₂ SO ₄ F ′: Factor of 0.1N NaOH

  In the present specification, the “carboxymethylated cellulose nanofiber” refers to one that maintains at least a part of the fibrous shape even when dispersed in water. Therefore, it is distinguished from carboxymethyl cellulose which is a kind of water-soluble polymer described later. When an aqueous dispersion of “carboxymethylated cellulose nanofiber” is observed with an electron microscope, a fibrous substance can be observed. On the other hand, even when an aqueous dispersion of carboxymethyl cellulose (usually powder), which is a kind of water-soluble polymer, is observed, fibrous substances are not observed. In addition, the “carboxymethylated cellulose nanofiber” can observe the peak of cellulose I-type crystals when measured by X-ray diffraction, but the cellulose I-type crystals are not observed in the water-soluble polymer carboxymethylcellulose.

[Carboxylation]
As the carboxylation (oxidation) method, for example, a cellulose raw material or defibrated cellulose fiber is treated with an oxidizing agent in the presence of an N-oxyl compound and a compound selected from the group consisting of bromide, iodide or a mixture thereof. The method of using and oxidizing in water is mentioned. By this oxidation, the primary hydroxyl group at the C6 position of the glucopyranose ring on the cellulose surface is selectively oxidized, and cellulose fibers having an aldehyde group and a carboxyl group (—COOH) or a carboxylate group (—COO ⁻ ) on the surface are obtained. Obtainable. The concentration of cellulose during the reaction is not particularly limited, but is preferably 5% by mass or less.

  The N-oxyl compound refers to a compound that can generate a nitroxy radical. As the N-oxyl compound, any compound can be used as long as it promotes the target oxidation reaction. Examples include 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO) and its derivatives (for example, 4-hydroxy TEMPO).

  The amount of the N-oxyl compound used is not particularly limited as long as it is a catalytic amount capable of oxidizing cellulose. For example, 0.01 to 10 mmol is preferable, 0.01 to 1 mmol is more preferable, and 0.05 to 0.5 mmol is more preferable with respect to 1 g of absolutely dry cellulose. Moreover, about 0.1-4 mmol / L is preferable with respect to the reaction system.

  Bromide is a compound containing bromine, examples of which include alkali metal bromides that can dissociate and ionize in water. Further, an iodide is a compound containing iodine, and examples thereof include alkali metal iodide. The amount of bromide or iodide used can be selected as long as the oxidation reaction can be promoted. The total amount of bromide and iodide is, for example, preferably 0.1 to 100 mmol, more preferably 0.1 to 10 mmol, and still more preferably 0.5 to 5 mmol with respect to 1 g of absolutely dry cellulose.

  As the oxidizing agent, known ones can be used, and examples thereof include halogen, hypohalous acid, halous acid, perhalogen acid or salts thereof, halogen oxide, peroxide and the like. Of these, sodium hypochlorite is preferred because it is inexpensive and has a low environmental impact. The amount of the oxidizing agent used is preferably 0.5 to 500 mmol, more preferably 0.5 to 50 mmol, still more preferably 1 to 25 mmol, and even more preferably 3 to 10 mmol with respect to 1 g of absolutely dry cellulose. For example, 1-40 mol is preferable with respect to 1 mol of N-oxyl compounds.

  The oxidation of cellulose allows the reaction to proceed efficiently even under relatively mild conditions. Therefore, the reaction temperature is preferably 4 to 40 ° C, and may be room temperature of about 15 to 30 ° C. As the reaction proceeds, a carboxyl group is generated in the cellulose, so that the pH of the reaction solution is reduced. In order to advance the oxidation reaction efficiently, an alkaline solution such as an aqueous sodium hydroxide solution is added to maintain the pH of the reaction solution at about 8 to 12, preferably about 10 to 11. The reaction medium is preferably water because it is easy to handle and hardly causes side reactions.

  The reaction time in the oxidation reaction can be appropriately set according to the degree of progress of oxidation, and is usually 0.5 to 6 hours, for example, about 0.5 to 4 hours.

  The oxidation reaction may be performed in two stages. For example, oxidized cellulose obtained by filtration after completion of the first stage reaction can be oxidized again under the same or different reaction conditions. Thereby, it can oxidize efficiently by reaction of the 2nd stage, without receiving reaction inhibition by the salt produced as a by-product by reaction of the 1st stage.

Another example of the carboxylation (oxidation) method includes a method of oxidizing by contacting a gas containing ozone and a cellulose raw material or a defibrated cellulose fiber. This oxidation oxidizes at least the 2-position and 6-position hydroxyl groups of the glucopyranose ring, and causes degradation of the cellulose chain. 50-250 g / m < ³ > is preferable and, as for the ozone concentration in the gas containing ozone, 50-220 g / m < ³ > is more preferable. The amount of ozone added to the cellulose raw material or defibrated cellulose fiber is preferably 0.1 to 30 parts by mass, and preferably 5 to 30 parts by mass with respect to 100 parts by mass of the solid content of the cellulose raw material or defibrated cellulose fiber. It is more preferable. 0-50 degreeC is preferable and, as for ozone treatment temperature, 20-50 degreeC is more preferable. The ozone treatment time is not particularly limited, but usually about 1 to 360 minutes and about 30 to 360 minutes are preferable. When the conditions for the ozone treatment are within these ranges, the cellulose can be prevented from being excessively oxidized and decomposed, and the yield of oxidized cellulose can be improved. After the ozone treatment, an additional oxidation treatment may be performed using an oxidizing agent. The oxidizing agent used for the additional oxidation treatment is not particularly limited, and examples thereof include chlorine compounds such as chlorine dioxide and sodium chlorite, oxygen, hydrogen peroxide, persulfuric acid, and peracetic acid. As the additional oxidation treatment, for example, a method in which these oxidizing agents are dissolved in a polar organic solvent such as water or alcohol to prepare an oxidizing agent solution, and a cellulose raw material or defibrated cellulose fiber is immersed in the solution can be used.

  The amount of the carboxyl group in the carboxylated (oxidized) cellulose or carboxylated (oxidized) cellulose nanofiber is 0.6 to 0.6 based on the absolute dry mass of the carboxylated (oxidized) cellulose or carboxylated (oxidized) cellulose nanofiber. 2.0 mmol / g is preferable, and 1.0 to 2.0 mmol / g is more preferable. The amount of the carboxyl group can be adjusted by controlling the reaction conditions such as the addition amount of the oxidizing agent and the reaction time.

[Esterification]
Examples of the esterification method include a method of mixing a powder or aqueous solution of phosphoric acid compound A with a cellulose raw material or defibrated cellulose fiber, and an aqueous solution of phosphoric compound A is added to a slurry of the cellulose raw material or defibrated cellulose fiber. Examples thereof include phosphoric acid esterification methods.

  Examples of the phosphoric acid compound A include phosphoric acid, polyphosphoric acid, phosphorous acid, phosphonic acid, polyphosphonic acid, and esters thereof. The phosphoric acid compound A may be in the form of a salt. The phosphoric acid compound A is preferably a compound having a phosphoric acid group because it is low in cost and easy to handle, and a phosphoric acid group can be introduced into the cellulose of the pulp fiber to improve the fibrillation efficiency. Examples of the compound having a phosphate group include phosphoric acid, sodium dihydrogen phosphate, disodium hydrogen phosphate, trisodium phosphate, sodium pyrophosphate, sodium metaphosphate, potassium dihydrogen phosphate, and dipotassium hydrogen phosphate. , Tripotassium phosphate, potassium pyrophosphate, potassium metaphosphate, ammonium dihydrogen phosphate, diammonium hydrogen phosphate, triammonium phosphate, ammonium pyrophosphate, ammonium metaphosphate, and the like. A phosphoric acid type compound may be used individually by 1 type, and may use 2 or more types together. Among these, phosphoric acid, phosphoric acid sodium salt, phosphoric acid potassium salt, phosphoric acid, from the viewpoint that phosphoric acid group introduction efficiency is high, is easy to be defibrated in the following defibrating process, and is industrially applicable. Are preferred, and sodium dihydrogen phosphate and disodium hydrogen phosphate are more preferred. The phosphoric acid compound A is preferably used as an aqueous solution. Thereby, the uniformity of reaction can be improved and the efficiency of introduction of phosphate groups can be increased. The pH of the aqueous solution of the phosphoric acid compound A is preferably 7 or less, whereby the efficiency of introducing a phosphate group can be increased. As for such pH, 3-7 are more preferable, and can suppress hydrolysis of a pulp fiber by this.

  Examples of the phosphoric acid esterification method include the following methods. Phosphoric acid compound A is added to a cellulose raw material having a solid content concentration of 0.1 to 10% by mass or a dispersion of defibrated cellulose fibers while stirring to introduce phosphate groups into the cellulose. The addition amount of the phosphoric acid compound A is preferably 0.2 parts by mass or more and more preferably 1 part by mass or more as the amount of phosphorus atoms with respect to 100 parts by mass of the cellulose raw material or defibrated cellulose fiber. Thereby, the yield of fine fibrous cellulose can be improved more. The upper limit is preferably 500 parts by mass or less, and more preferably 400 parts by mass or less. As a result, the improvement in yield does not reach its peak, and the cost is efficient. Therefore, 0.2 to 500 parts by mass is preferable, and 1 to 400 parts by mass is more preferable.

  In the esterification, in addition to the cellulose raw material or defibrated cellulose fiber and the phosphoric acid compound A, a powder or an aqueous solution of another compound (compound B) may be mixed. Compound B is not particularly limited, but a nitrogen-containing compound showing basicity is preferable. As used herein, “basic” means that the aqueous solution exhibits a pink to red color in the presence of a phenolphthalein indicator, or the pH of the aqueous solution is greater than 7. Although the nitrogen-containing compound which shows basicity is not specifically limited as long as the effect of this invention is exhibited, the compound which has an amino group is preferable. Examples of the compound having an amino group include urea, methylamine, ethylamine, trimethylamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, pyridine, ethylenediamine, and hexamethylenediamine, but are not particularly limited. Of these, urea is preferred because of its low cost and ease of handling. The amount of compound B added is preferably 2 to 1000 parts by weight, more preferably 100 to 700 parts by weight, based on 100 parts by weight of the solid content of the cellulose raw material or defibrated cellulose fiber. The reaction temperature is preferably 0 to 95 ° C, more preferably 30 to 90 ° C. Although reaction time is not specifically limited, Usually, it is about 1 to 600 minutes, and 30 to 480 minutes are more preferable. When the conditions for the esterification reaction are within these ranges, the cellulose can be prevented from being excessively esterified and easily dissolved, and the yield of the esterified cellulose can be improved. After dehydrating the obtained phosphate esterified cellulose suspension, it is preferable to heat-treat at 100 to 170 ° C. from the viewpoint of suppressing hydrolysis of cellulose. Furthermore, while water is contained during the heat treatment, it is preferably heated at 130 ° C. or less, preferably 110 ° C. or less, and after removing water, heat treatment is preferably performed at 100 to 170 ° C.

  The degree of phosphate group substitution per glucose unit in the esterified cellulose is preferably 0.001 or more. Thereby, subsequent defibration can fully be performed. The upper limit is preferably 0.40 or less. Thereby, swelling or dissolution of cellulose can be suppressed and nanofibers can be obtained efficiently. Accordingly, the phosphate group substitution degree is preferably 0.001 to 0.40. Celluloses repel each other electrically by introducing phosphate groups into the cellulose. For this reason, the cellulose which introduce | transduced the phosphate group can be nano-defibrated easily. Since the subsequent defibration can be performed efficiently, the prepared phosphorylated cellulose or phosphorylated cellulose nanofiber is preferably washed with cold water after boiling.

  When the product obtained after each chemical modification is in a salt form, desalting treatment may be performed to replace a salt (for example, sodium salt) with a proton.

<(2-4) Defibration>
As a method of defibrating treatment, for example, a method of applying high pressure to a cellulose raw material or modified cellulose (preferably an aqueous dispersion thereof), a method of applying a strong shearing force, and both a high pressure and a strong shearing force. The method of applying is mentioned. The high pressure is not particularly limited, but is usually 50 MPa or more, preferably 100 MPa or more, more preferably 140 MPa or more. The apparatus used for defibration is not particularly limited, and examples thereof include a high-speed rotation type, a colloid mill type, a high-pressure type, a roll mill type, and an ultrasonic type. By using these apparatuses, a strong shearing force can be applied to cellulose or chemically modified cellulose (preferably an aqueous dispersion of cellulose or chemically modified cellulose). Among these, a device capable of applying a high pressure and a strong shearing force to the aqueous dispersion (for example, a wet high pressure or ultrahigh pressure homogenizer) is preferable. Thereby, defibration can be performed efficiently. The number of treatments (passes) of the defibrating device may be one time, two times or more, and preferably two times or more. Prior to the defibrating treatment, preliminary treatments such as mixing, stirring, emulsification, and dispersion may be performed as necessary. A device such as a high-speed shear mixer may be used for the preliminary treatment.

<Mass ratio of (3) (A) and (B) components>
The content of each of the components (A) and (B) of the composition of the present invention is not particularly limited, but the mass of the component (B) relative to the total mass (absolute dry mass) of the starch contained in the component (A) ( The ratio (absolute dry total mass) is preferably 0.1% by mass or more, more preferably 1% by mass or more, and further preferably 5% by mass or more. Thereby, sufficient starch aging inhibitory effect can be acquired. The upper limit is preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 20% by mass or less. Thereby, the food texture becomes better. Therefore, the ratio is preferably 0.1 to 50% by mass, more preferably 1 to 30% by mass, and still more preferably 5 to 20% by mass.

<(4) Water-soluble polymer>
The composition of the present invention may contain a water-soluble polymer. The water-soluble polymer may be any water-soluble polymer other than the component (A), such as cellulose derivatives (eg, carboxymethyl cellulose, methyl cellulose, hydroxypropyl cellulose, ethyl cellulose), xanthan gum, xyloglucan, dextrin, dextran, Carrageenan, locust bean gum, alginic acid, alginate, pullulan, gum arabic, gellan gum, gellan gum, polydextrose, pectin, chitin, water-soluble chitin, chitosan, casein, albumin, soy protein lysate, peptone, polyvinyl alcohol, polyacrylamide, Sodium polyacrylate, polyvinylpyrrolidone, polyvinyl acetate, polyamino acid, polylactic acid, polymalic acid, polyglycerin, latex, rosin sizing agent, petroleum resin Sizing agent, urea resin, melamine resin, epoxy resin, polyamide resin, polyamide / polyamine resin, polyethyleneimine, polyamine, vegetable gum, polyethylene oxide, hydrophilic cross-linked polymer, polyacrylate, starch polyacrylic acid copolymer, tamarind Examples include gum, guar gum and colloidal silica and mixtures of one or more thereof. Among these, at least one selected from carboxymethyl cellulose and a salt thereof is preferable from the viewpoint of compatibility.

  The ratio of the mass of the water-soluble polymer to the mass of the component (B) (absolute dry mass) is preferably 5% by mass or more. Thereby, the effect of redispersibility can be sufficiently obtained. On the other hand, the upper limit is preferably 50% by mass or less. Thereby, the viscosity characteristic and dispersion stability of cellulose nanofiber can be improved. Therefore, the ratio is preferably 5 to 50% by mass.

<(5) Viscosity of composition measured with Rapid Visco Analyzer>
The following measurement conditions by the Rapid Visco Analyzer (RVA) of the composition of the present invention:
RVA measuring instrument: Physica MCR301, manufactured by Anton paar;
Temperature conditions: The temperature was raised from 50 ° C. to 93 ° C. at a rate of temperature rise of 10.75 ° C./min, held for 7 minutes, then dropped from 93 ° C. to 50 ° C. at a rate of temperature drop of 10.75 ° C./min and held for 3 minutes;
Rotational speed: 160 rpm; and jig: ST24 / -2V-2V
It is preferred that the viscosity measured at
(1) The ratio of the viscosity after 1200 seconds (at the end of cooling) to the viscosity after 800 seconds (at the start of cooling) from the start of measurement is 2.0 or less, preferably 1.8 or less.
(2) The viscosity of the composition using water instead of the component (B) after 1200 seconds from the start of measurement is 0.2 Pa · s or more.

<(6) Optional component>
The composition of this invention may contain components (arbitrary component) other than (A) component, (B) component, and water-soluble polymer as needed. Examples of optional components include surfactants, modified starches, starch aging inhibitors (other than high amylose-containing starches and cellulose fibers), modifiers, and other components that are permitted as optional ingredients for foods. . Examples of the surfactant include glycerin fatty acid ester, sorbitan fatty acid ester, and sucrose fatty acid ester. Examples of the processed starch include acetylated starch.

  Examples of the modifier include elasticity enhancers, protein freezing denaturation inhibitors, masking agents, browning inhibitors, antioxidants, and shelf life improvers. Examples of the elasticity enhancer include egg protein and milk protein. As a protein freezing denaturation inhibitor, what is necessary is just to exhibit the effect which prevents the fluffiness of meat in a freezing process.

<(7) Manufacturing method of composition>
The manufacturing method of the composition of this invention should just be a method including mixing starch and a cellulose nanofiber. For example, a dispersion of cellulose nanofibers, a dry solid of the dispersion, a wet solid of the dispersion, a mixture of cellulose nanofibers and a water-soluble polymer, a dry solid of the mixture, A method of adding starch to wet solids or other known forms of cellulose nanofibers and mixing them can be mentioned. In the present specification, the wet solid is a solid in an intermediate form between the dispersion or mixture and the dry solid. When used as a dry solid, the cellulose nanofibers are preferably mixed with a water-soluble polymer from the viewpoint of dispersibility when mixing materials.

  The dry solid and wet solid may be prepared by dehydrating and / or drying a dispersion or mixture of cellulose nanofibers. The dehydration method and the drying method are not particularly limited, and examples thereof include spray drying, pressing, air drying, hot air drying, vacuum drying, and other conventionally known methods. Examples of the drying apparatus include the following apparatuses: continuous drying apparatuses (for example, a tunnel drying apparatus, a band drying apparatus, a vertical drying apparatus, a vertical turbo drying apparatus, a multistage disk drying apparatus, an aeration drying apparatus, Rotary dryer, air dryer, spray dryer dryer, spray dryer, cylindrical dryer, drum dryer, screw conveyor dryer, rotary dryer with heating tube, vibratory transport dryer), and batch dryer (For example, box-type drying device, aeration drying device, vacuum box-type drying device, stirring drying device). These drying apparatuses may be used alone or in combination of two or more. The drying device is preferably a drum drying device. Thereby, since heat energy can be directly supplied to the material to be dried uniformly, energy efficiency can be improved. Also, the dried product can be recovered immediately without applying more heat than necessary.

<(8) Form of composition>
The form of the composition of the present invention is not particularly limited, and examples thereof include liquids (for example, aqueous solutions, dispersions, gels, and solids (for example, dry solids and wet solids)).

<(9) Starch aging inhibitor>
The composition of the present invention can suppress aging of starch by replacing at least a part of the starch with the composition of the present invention, as compared with the starch before replacement. Therefore, the composition of the present invention is useful as an active ingredient of a starch aging inhibitor.

  The starch (preferably, the above-mentioned starch-based raw material) is not particularly limited, but high amylose starch (preferably, the above-mentioned starch having an amylose content of 15% by mass or more) is preferable. High amylose starch is more susceptible to aging than other starches, but aging can be suppressed by adding the composition of the present invention.

<(10) Starch-based food production method and modification method>
By using the composition of the present invention instead of at least a part of starch, which is a raw material for starch-based foods, deterioration over time due to aging of starch can be suppressed as compared to ordinary starch-based foods. For this reason, the composition of the present invention can be used for the production of starch-based foods and the modification of starch-based foods such as improving the storage stability, improving flavor, and suppressing texture reduction.

  The starch-based food is not particularly limited as long as it is a starch-based food. For example, cooked rice such as fried rice, cooked rice, and rice balls; processed rice products such as rice cakes, rice crackers and rice crackers; udon, pasta, Chinese noodles, buckwheat noodles Noodles such as fertilizer, Daifuku, Warabimochi, etc .; Western confectionery such as sponge cake, waffle, custard cream, donut, baked confectionery (for example, cookies, biscuits, crackers, dry bread, pretzel, pie); bread, French bread, Examples include breads such as croissants and steamed bread; Chinese buns such as anman and meat buns; confectionery materials such as flower paste and filling; retort foods such as instant curry; and seasonings such as curry roux, ketchup, mayonnaise, sauce and sauce. In the present invention, the starch-based food is a starch-based food made from a high amylose starch (preferably, a starch having an amylose content of 15% by mass or more as described above) as a starch (preferably, the starch-based raw material described above). Is preferred.

  The amount of starch-based food added to the composition of the present invention is not particularly limited as long as it is an effective amount capable of suppressing starch aging, but the content of the high amylose starch in the raw material and the component (A) in the composition of the present invention The ratio of the content of the component (B) with respect to the total is usually 0.1% by mass or more, preferably 1% by mass or more. Although an upper limit is not specifically limited, It is 50 mass% or less.

  Further, the method of adding the composition of the present invention to the food is not particularly limited, and may be added directly to the starch-containing raw material. In the production process, it is added at any timing together with the starch-containing raw material and other raw materials. Also good.

  Hereinafter, although an example is given and the present invention is explained still in detail, the present invention is not limited to these.

[Production of carboxymethylated cellulose nanofibers]
In a stirrer capable of mixing pulp, 200 g of dry pulp (NBKP (coniferous bleached kraft pulp), manufactured by Nippon Paper Industries Co., Ltd.) and 111 g of sodium hydroxide by dry mass (2. 25 mol) and water was added so that the pulp solid content was 20% (w / v). Thereafter, after stirring at 30 ° C. for 30 minutes, 216 g of sodium monochloroacetate (in terms of active ingredient, 1.5 times mol per glucose residue of pulp) was added. After stirring for 30 minutes, the temperature was raised to 70 ° C. and stirred for 1 hour. Thereafter, the reaction product was taken out, neutralized and washed to obtain a carboxymethylated pulp having a carboxymethyl substitution degree of 0.25 per glucose unit. This was made into 1% solid content with water, and fibrillated by treating with a high-pressure homogenizer five times at 20 ° C. and a pressure of 150 MPa to obtain an aqueous dispersion of carboxymethylated cellulose nanofibers having a concentration of 1%. The average fiber diameter was 15 nm and the aspect ratio was 50.

<Example 1>
Thai rice crystalline rice flour (amylose content 25%, Thai-produced air-flow crushed) 3g (starch content: 2.8g) and carboxymethylated cellulose nanofiber 0.18g (converted to solid content, 1g aqueous dispersion 18g Was added) and a sample was obtained. In order to examine the viscosity characteristics of the sample, RVA (Rapid Visco Analyzer) measurement was performed. The measuring instrument used was Physica MCR301, manufactured by Anton paar. The measurement conditions were as follows:
Temperature: The temperature was raised from 50 ° C. to 93 ° C. at a rate of temperature rise of 10.75 ° C./min, held for 7 minutes, then dropped from 93 ° C. to 50 ° C. at a rate of temperature drop of 10.75 ° C./min and held for 3 minutes;
Rotational speed: 160 rpm; and jig: ST24 / -2V-2V.

<Comparative Example 1>
The same procedure as in Example 1 was performed except that 18 g of water was added instead of the aqueous dispersion of carboxymethylated cellulose nanofibers.

<Example 2>
The same procedure as in Example 1 was performed except that momiroman (amylose content: 25.30%, produced by airflow pulverization from 2015) was used in place of the crystalline rice flour of Thai rice.

<Comparative example 2>
The same procedure as in Example 2 was performed except that 18 g of water was added instead of the aqueous dispersion of carboxymethylated cellulose nanofibers.

<Comparative Example 3>
The same procedure as in Example 1 was performed except that snow rice was used instead of the crystalline rice flour of Thai rice (amylose content 8.1%, produced by airflow pulverization from 2014 in Miyagi Prefecture).

<Comparative example 4>
The same procedure as in Comparative Example 3 was performed except that 18 g of water was added instead of the aqueous dispersion of carboxymethylated cellulose nanofibers.

  The results of Example 1 and Comparative Example 1, the results of Example 2 and Comparative Example 2, and the results of Comparative Examples 3 and 4 are shown in FIGS. In addition, Table 1 shows the viscosities and viscosity ratios of the examples and comparative examples.

  From FIG. 1, it was shown that the increase in the viscosity due to cooling was suppressed in the sample of Example 1 as compared with the sample of Comparative Example 1. From FIG. 2, it was shown that the increase in the viscosity accompanying cooling was also suppressed in the sample of Example 2 as compared with the sample of Comparative Example 2. On the other hand, as apparent from FIG. 3, in Comparative Examples 3 and 4, almost no increase in viscosity due to cooling was observed. Since aging of rice is a phenomenon in which amylose aggregates and restructures the crystal structure, the above results indicate that cellulose nanofibers can suppress aging of starch having a high amylose content.

Claims (8)

(A) component: starch-based raw material containing at least starch having an amylose content of 15% by mass or more, and (B) component: a composition containing cellulose nanofibers.   The composition of Claim 1 whose ratio of the mass of (B) component with respect to the total mass of the starch contained in (A) component is 0.1-50 mass%.   (B) The composition of Claim 1 or 2 in which a component contains a chemically modified cellulose nanofiber.   The composition according to any one of claims 1 to 3, wherein the chemically modified cellulose nanofiber is a carboxymethylated cellulose nanofiber having a degree of carboxymethyl substitution per glucose unit of 0.01 to 0.50.   The starch aging inhibitor which uses the composition of any one of Claims 1-4 as an active ingredient.   The starch food additive which uses the composition of any one of Claims 1-4 as an active ingredient.   A method for producing a starch-based food, comprising using the composition according to any one of claims 1 to 4 in place of at least a part of starch that is a raw material of the starch-based food.   A method for modifying starch-based foods, wherein the composition according to any one of claims 1 to 4 is used in place of at least a part of starch as a raw material for starch-based foods.

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