JPH01202235A - Quality improving agent for starchy food - Google Patents

Abstract

PURPOSE:To obtain a quality improving agent for starchy foods having excellent quality improving effect, in safety and low cost, by using a partial decomposition product of a protein obtained by multi-stage partial decompositions containing alkali hydrolysis of a grain protein as an active ingredient. CONSTITUTION:A grain protein such as wheat gluten, corn gluten or soybean protein is subjected to multi-stage partial decompositions comprising a combination of hydrolysis by an alkali and one or more of decomposition treatments by an acid, an enzyme, an oxidizing agent and a reducing agent to give a partial decomposition product of protein. Solely said partial decomposition product or a mixture of said product with a surfactant of multihydric alcohol fatty ester type in a weight ratio 1:6-6:1 is used as a quality improve agent and added to starchy food materials such as breads and noodles in a ratio of 0.01-5wt.%.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to a quality improving agent for starchy foods. For more information, see wheat gluten, corn gluten,
This invention relates to a quality improver that is made of a partially decomposed product of grain proteins such as soybean protein and is used when added to various proteinaceous food materials.

(b) Conventional technology Breads and noodles are typical so-called starchy foods whose main ingredient is starch. Various quality improving agents are added to such starchy foods. As typical examples, so-called polyhydric alcohol fatty acid ester type surfactants such as glycerin fatty acid ester, propylene glycol fatty acid ester, and sucrose fatty acid ester are widely used. Acids and gluconolactones are used in combination (Japanese Patent Publication No. 42887/1983, Japanese Patent Application Laid-Open No. 1983-1988)
11333=1 and No. 55-118335), and the use of the glycerin fatty acid ester after subjecting it to a specific treatment (Japanese Patent Publication No. 59-41379) has been proposed.

1. It has recently been announced that gluten partial hydrolyzate obtained by treating wheat gluten in a bioreactor with immobilized pepsin can be applied to improve the quality of confectionery such as sponge cakes and bread. (Chemical Industry Times; June 25, 1986).

(c) Problems to be solved by the invention However, although polyhydric alcohol fatty acid ester type surfactants are recognized as food additives, they are themselves chemically synthesized products, so there are concerns about their toxicity. be. Furthermore, these surfactants have not always been satisfactory in terms of cost and quality improvement effects.

On the other hand, the partial decomposition product of wheat gluten obtained by the enzymatic decomposition described above is highly safe, but does not have sufficient expectations in terms of cost and effectiveness.

This invention was made in view of this situation,
In particular, we would like to provide a new quality improver for starch raw materials that is a safe and inexpensive additive that can replace the widely used polyhydric alcohol fatty acid ester type surfactant as mentioned above, but also has a quality improvement effect. It is something to do.

(d) Means for Solving the Problems From the above perspective, the present inventors have conducted various studies and examinations on partial decomposition methods for grain protein partial decomposition products such as the above-mentioned wheat gluten partial decomposition products, and have found that alkaline decomposition A specific protein partial decomposition product obtained by a sequential multi-stage decomposition treatment that requires treatment and is combined with a decomposition treatment using an acid, an enzyme, an oxidizing agent, or a reducing agent is (1) What is a normal protein partial decomposition product? In addition to being a new substance with completely different properties, (11) simple alkaline decomposition products, enzymatic decomposition products,
We have discovered the fact that this product has a superior quality improvement effect on starchy foods compared to oxidized decomposition products.

Thus, according to the present invention, a partially decomposed product of grain protein has the following physical properties: (a) a weight average molecular weight (by gel filtration method) of 500;
~90000 turn, (b) UV absorption λmaX is around 260 to 28 Onm, and infrared absorption is 1400.1630 and 3400 cm
-', (c) Isoelectric point is in the range of 3.9 to 5.0, (d) pH buffering property (5% by weight aqueous solution of this product 10h + (j pH from 6 to 2 I to lower it to
(e) Soluble in water and insoluble in methanol, ethanol, acetone, and ether (f) Powder with pale yellow to reddish brown appearance (g)
Color develops due to xanthoprotein reaction and ninhydrin reaction. (h) Strong surface tension lowering ability (drink this product in pure water at 25°C).
By adding % by weight, the surface tension of pure water can be increased to 50d.
yne/cm (measured with a Dunui surface tension meter).

(i) Strong emulsifying ability (by using this product 19, water-soybean oil mixture 10 containing at least 30% by weight of soybean oil)
Completely emulsify 09 (keep it uniformly emulsified for at least 10 minutes,
There is provided an agent for improving the quality of starchy foods comprising a substance characterized by: (meaning that it can be maintained preferably for more than 1 hour).

The protein partial decomposition product specified above is itself a new substance that had not been described in any literature prior to the filing of this application, and is particularly superior to conventional grain proteins in terms of the above-mentioned surface tension lowering ability (h) and emulsifying ability (i). It should be distinguished from partially decomposed products.

The quality improving agent of this invention is used by being added to the raw materials of bulk foods, and when added in the required amount, it exhibits various quality improving effects. For example, the so-called anti-aging effect that prevents or suppresses the hardening of breads and noodles due to the denaturation of Denn 7S; The fineness and stickiness of the dough during noodle making can be adjusted to an appropriate level, and during bread making, dough expansion due to yeast fermentation can be prevented, and ``Sudachi'' can provide finer and more uniform bread. Quality improvement effects can be obtained. These quality improvement effects are much better than those achieved by alkaline decomposition, enzymatic decomposition, reductive decomposition, oxidative decomposition, etc.

Typical starchy foods that are the subject of this invention are breads and noodles, but other than these, there are also various other foods and food ingredients whose main ingredient is starch, such as kutsky and sponge cake.

In this invention, grain protein refers to protein contained in grains, and examples of grains include barley (e.g., wheat),
Examples include corn and beans (eg, soybeans). Among the proteins contained in such grains, wheat protein, for example, contains glutenin and gliadin as main components,
Commonly referred to as wheat gluten. Corn protein contains zein as a main component and is usually referred to as corn gluten. These are all known substances and can be obtained by separating or extracting them from grains using conventional methods. For example, to obtain wheat protein (wheat gluten), if you add a small amount of water to wheat flour and knead it until hard, then knead it in a large amount of water, the starch will be suspended in the water and the gluten content will become a sticky lump. It remains. If this operation is repeated several times by changing the water, a grey-brown, viscous lump can be obtained. For the preparation of the partially decomposed product of this invention, such lumps can be used as they are, but their dried products may also be used, and further purified products, partially modified products, etc. may also be used. . For example, wheat gluten
Dried products are commercially available and can be easily obtained.

Other commercially available corn gluten and soybean protein can be easily used.

The protein may be either a crude product or a purified product, but it is preferable to use one containing 70% or more protein.

The partially decomposed products of the present invention are obtained by subjecting grain proteins to a multistage decomposition treatment that combines hydrolysis treatment with an alkali and decomposition treatment using an acid, an enzyme, an oxidizing agent, or a reducing agent. That is, it can be obtained by combining alkaline decomposition treatment and other decomposition treatment.

The hydrolysis treatment with an alkali is suitably carried out by heating in a dilute aqueous alkali solution. Usually, an aqueous solution or aqueous dispersion of the substance to be hydrolyzed is prepared in the presence of an alkaline agent such as sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, etc.
It is suitable to carry out stirring at 80° C. for about 10 to 600 minutes. °The aqueous solution or aqueous dispersion of the substance to be hydrolyzed is preferably 2 to 40% by weight, and the amount of alkaline agent used is 0.1 to 69% by weight per 20 g of the substance to be hydrolyzed. It is preferable to do so.

On the other hand, among the other decomposition treatments that can be combined with the hydrolysis treatment using an alkali, the decomposition treatment using an acid is preferably carried out by heating in a dilute aqueous acid solution.

Usually, an aqueous solution or aqueous dispersion of the substance to be decomposed is heated to about 60 to 120°C in the presence of an inorganic acid such as hydrochloric acid or sulfuric acid or an organic acid such as acetic acid.
It is suitable to carry out stirring for about 10 to 600 minutes. The quantitative conditions here are preferably the same as those for the alkaline hydrolysis described above.

Similarly, enzymatic decomposition treatment is suitably carried out in a dilute aqueous solution of an enzyme with protease activity, and usually a small amount of an enzyme such as pepsin, alkaline protease, or papain is present in the aqueous solution or aqueous dispersion of the substance to be decomposed. Under the optimal pH condition for this enzyme, at about 10 to 60°C, about 60°C
Runs for ~600 minutes.

Here, the quantitative conditions are preferably the same as above except that the amount of enzyme used is 0.02 to 59% of the target substance 209 to be decomposed.

Similarly, decomposition treatment using a reducing agent or an oxidizing agent is suitably carried out in a dilute aqueous solution of the reducing agent or oxidizing agent, and usually sulfites, thiol compounds, and erythorbine are added to the aqueous solution or aqueous dispersion of the target substance. The reaction is carried out at about 10 to 100° C. for 10 to 600 minutes in the presence of a small amount of a reducing agent such as an acid or hydrazine or an oxidizing agent such as hydrogen peroxide or hypochlorite. The quantitative conditions at this time are preferably the same as those described above except that the amount of reducing agent or oxidizing agent used with respect to the object to be decomposed 209 is 0.1 to 59.

The order of the multi-stage decomposition processing is not particularly limited.

That is, after first subjecting raw materials such as wheat gluten to alkaline hydrolysis treatment (A), any of the above-mentioned decomposition treatment using acids, enzymes, reducing agents, and oxidizing agents (B) (decomposition treatment other than alkali) Alternatively, the decomposition treatment may be performed in the reverse order. Alternatively, it can be obtained by first subjecting it to a non-alkali decomposition treatment (B), then subjecting it to an alkali hydrolysis treatment (A), and then again subjecting it to a non-alkali decomposition treatment (B).

In addition, neutralization treatment may be performed as appropriate between these treatments.

In this invention, more excellent quality improvement effects are observed when the weight average molecular weight is in the range of 500 to 60,000.

These molecular weights can be appropriately controlled by adjusting the conditions of the above-mentioned partial decomposition treatment.

In addition, these molecular weights are 1600°6 as a standard substance.
Using sodium polystyrene sulfonate having a molecular weight of 500, 16000, 6500G, and 88,000, Sephadex G-75 or G manufactured by Pharmacia was used.
This is a value measured by a gel filtration method using -100 as a carrier.

The protein partial decomposition product thus obtained can be used as a quality improver for starchy foods in the form of an aqueous solution after decomposition, but it can also be used as a powder after drying. In addition, purified products obtained by desalination treatment or decolorization treatment, such as ultrafiltration, can also be used satisfactorily.

The quality improving agent of this invention is usually added and used in the manufacturing process of starchy foods such as breads and noodles, and exhibits various effects.

Bread-making methods include the dough method and the straight method, but either method may be used, and the addition process and timing are not particularly limited. good.

On the other hand, when used in noodle making, the addition process and timing are not particularly limited, but it can usually be added to the noodle making raw materials in the noodle dough kneading process.

The amount added during bread making is 0.
A suitable content is 0.01 to 5% by weight. Such addition makes the bread dough smooth, improving processability and damage recovery properties, and improves the water retention of the resulting bread, thereby preventing or suppressing aging. Furthermore, the texture of the obtained bread will be fine and uniform, and the volume of the bread will be increased compared to conventional quality improvers. It should be noted that if the amount added is less than 0.01ME1%, a sufficient quality improvement effect will not be exhibited, and even if it is added in an amount of 5% by weight or more, the effect of negating the economic disadvantages will not be exhibited, which is not preferable. Normally, from the viewpoint of overall quality improvement effect and cost, the amount added is preferably 0.05 to 3% by weight, and 0.1-3% by weight.
More preferably, the content is 1% by weight.

However, if the main purpose is to adjust the dough or increase the volume of the bread, an amount of 0.02 to 0.02 tons or oria% is sufficient; if the main purpose is to improve the anti-aging properties of the bread, The content is preferably 0.05% by weight or more.

On the other hand, additives used in noodle making include wheat, buckwheat, rice, rye,
0.0 for noodle raw materials such as triticale and corn
It is sufficient to add 1 to 5% by weight, preferably 0.05 to 3% by weight.
The amount is preferably 0.1 to 1% by weight.

This addition prevents or suppresses aging of the noodles, improves the texture, flakiness, etc., and improves the yield and storage stability during noodle production. Further, in the case of dry noodles or instant noodles, it can promote the return of the noodles, and in the case of packaged boiled noodles, it can prevent adhesion to the packaging material.

The quality improving agent of the present invention may contain other quality improving components in addition to the above-mentioned protein partial decomposition products. In particular, one preferred embodiment is to use it in combination with a polyhydric alcohol fatty acid ester type surfactant such as sucrose fatty acid ester or glycerin fatty acid ester, or lecithin. At this time, the blending ratio of protein partial decomposition product and surfactant is 1 = 6 ~
A ratio of 6:l (weight ratio) (preferably 1:4 to 4:l) is more preferable because a synergistic quality improvement effect can be obtained.

Further, commonly used preservatives such as ethanol, propionic acid, lactic acid, sorbic acid, dehydroacetic acid, and common salt may be used in combination, and this is a preferred use.

(e) Examples This invention will be explained in detail by Examples and Test Examples.

Examples 1 to 10 (Preparation of decomposition products by partial decomposition of wheat gluten with acid and subsequent partial decomposition with alkali) 0.59 in terms of hydrogen chloride. Wheat gluten (reagent) manufactured by Wako Pure Chemical Industries (Madhi) 20 in flasks containing 00 g of hydrochloric acid aqueous solution corresponding to Ig, 29 and 4 g, respectively.
g was added thereto, and the mixture was heated and stirred at 80°C and 100°C for 60 minutes.

Thereafter, neutralize with caustic soda and bring the total amount to 2009 with pure water to prepare a 10% aqueous solution of the partial decomposition product of wheat gluten with acid, put each 1009 into a flask or autoclave 10III, and add 0.00% of caustic soda or sodium carbonate. Add amounts within the range of 5 to 29 separately to 80
The mixture was heated and stirred at 150° C. for 30 minutes to 360 minutes. Thereafter, the mixture was neutralized with hydrochloric acid and purified to a total fi of 2009 with pure water to obtain invention products No. 1 to IO, which are partial decomposition products of the present invention. Table 1 shows the decomposition conditions and the average molecular weight of the decomposition products.

(The following is a blank space) Invention product No. '1 which was desalted by isoelectric precipitation or dialysis was almost tasteless and odorless.

Examples II to +4 (Preparation of decomposed products by partial decomposition of corn gluten and soybean protein with acid and then partial decomposition with alkali) Using corn gluten manufactured by Nihon Shokuhin Kako (Aji) as raw material, same conditions as in Examples 6 and 1. Partial decomposition was carried out sequentially using acid and alkali to produce Invention Product No.

11.12 was obtained. The average molecular weights were 11,800 and 27,100, respectively.

In addition, using soybean protein obtained by defatting commercially available yuba with acetone as a raw material, partial decomposition was performed sequentially using acid and alkali under the same conditions as in Examples 6 and I to produce an invention! io,L3,1
I got 4.

The average molecular weights are 12,000 and 29,000, respectively.
child.

Example 15.16 (Preparation of decomposed product by partial decomposition of wheat gluten with alkali and subsequent partial decomposition with acid) Wheat gluten 209 used in Example 1-10 was added to aqueous solution 1009 in which caustic soda 29 or 49 was dissolved. te10
After heating and stirring at 0°C for 60 minutes, the mixture was neutralized with hydrochloric acid, and the weight was adjusted to 2 aog with pure water to prepare a 10% aqueous solution of partially decomposed wheat gluten with an alkali. Hydrochloric acid equivalent to 1 and 1 were added separately, and the mixture was heated and stirred at 100° C. for 60 minutes. After that, it was neutralized with caustic soda and made into a total of 32009 with pure water, making it Invention No. 1.
5.16 was obtained. Table 2 shows the decomposition conditions and the average molecular weight of the decomposed products.

Example 17 (Preparation of decomposed product by enzymatic partial decomposition of wheat gluten followed by alkali partial decomposition) Wheat gluten 209 used in Examples 1 to 10 was mixed with 0. IN
-Add to a flask containing hydrochloric acid solution 1509, pH 1.5
Obtain an aqueous solution of. Add 0.29 pepsin to this and 3
The reaction was carried out at 7°C for 90 minutes. Thereafter, a 10% aqueous solution of enzymatic partial decomposition of wheat gluten was prepared by neutralizing with caustic soda and adding pure water to a total of 12,009 ff.
19 g of caustic soda was added to the flask, and the mixture was heated and stirred for 60 minutes. Thereafter, the mixture was neutralized with hydrochloric acid and the total amount was adjusted to 200 g with pure water to obtain invention product N0817.

The average molecular weight was 29,000.

Example 18 (Preparation of decomposed product by partial decomposition of wheat gluten with a reducing agent and then partial decomposition with an alkali) Wheat gluten 209 used in Examples 1 to 10 was added to an aqueous solution 1009 in which sodium sulfite 49 was dissolved, 30
After stirring at ℃ for 60 minutes, prepare a 10% aqueous solution of partially decomposed wheat gluten with a reducing agent by adjusting the total amount to z009 with pure water, add 19 of caustic soda to the 1009, and heat and stir in a flask at 100℃ for 60 minutes. did. After that, it was neutralized with hydrochloric acid and the total amount was adjusted to 2009 with pure water. Invention product No. i
11 was obtained, and the L0 average molecular weight was 39,500.

Example 19 (Produced by IXI, a decomposition product obtained by partial decomposition of wheat gluten with alkali and then enzymatic partial decomposition (the order is reversed from Example +7)) Examples 1 to 1 in an aqueous solution 1009 in which 2 g of caustic soda was dissolved. Add the wheat gluten 209 used in step 10, heat and stir at 100°C for 60 minutes, neutralize with hydrochloric acid, and make a total fi of 2009 with pure water to prepare a 10% aqueous solution of the partial decomposition product of wheat gluten with alkali. The reagent hydrochloric acid was added to the 1009 to obtain an aqueous solution with a pH of 1.5, and this was reacted in a flask at 37° C. for 90 minutes with the addition of 0.19 pepsin. Thereafter, the mixture was neutralized with caustic soda and purified with pure water to give a total amount of 2009 (invention product) o, 19.

The average molecular m was 24:)00.

Example 20 (Partial decomposition of wheat gluten with an alkali and subsequent partial decomposition with a carbon dioxide agent) Preparation of a decomposed product by dissolving 2 g of caustic soda and adding 100 g of an aqueous solution.
20 ml of wheat gluten used in l11-10/Taka I] [1
After heating and stirring at OO'C for 60 minutes, neutralize with hydrochloric acid and adjust the weight to 2009 with pure water to prepare a 10% aqueous solution of partially decomposed wheat gluten with alkali.
Hydrogen peroxide equivalent to 0.59 in terms of Ht 2 O was added to 009, and the mixture was heated and stirred at 40° C. for 60 minutes. Thereafter, sodium thiosulfate in an amount equivalent to the remaining H t Ot was added, and the total amount was adjusted to 200 g with pure water to obtain Invention Product 20.

The average molecular weight was 37,000.

Below, various physical properties and particle dispersion effects of the partially degraded proteins of the present invention obtained in Examples 1 to 20 are shown in Table 3, and measurement results of surface tension and emulsification duration are shown in Table 4.

(Margin below) Table 3 (Continued) In the table, W on the raw material side means wheat gluten, C means corn gluten, and B means soybean protein. Note that a blank column means that no test was performed during measurement.

The measurement methods and test methods for each physical property and particle dispersion effect are as follows.

[Average molecular weight]

These molecular weights are 1600 and 6500 as standard substances.
This value was measured by a gel filtration method using sodium polystyrene sulfonate having a molecular weight of 16,000.65,000.88,000 and using Sephadex G-75 or G-100 manufactured by Pharmacia as a carrier.

[Isoelectric point]

1009 pieces of each of the invention products I to 20 obtained in the examples of the present invention were placed in a beaker, and 1N-HCl2 was added under stirring at room temperature.
was added 1 ma at a time, and l) H was measured. Obtained pl
(The pH 1ti at which the slope of the curve becomes gentle was defined as the isoelectric point.

[Buffer capacity]

From the I) + (curve obtained in the same manner as the isoelectric point measurement method, the amount of lN hydrochloric acid required to lower pn from 6 to 2 was defined as the buffering capacity. In addition, pn neutralization at this time curve,
Invention No. 1, No. 7. No, 11. and No. 1
3 are shown in Figures 1 (a) to (d).

(UV) 800 to 20 using a Hitachi U-3200 spectrophotometer
Absorbance was measured in the 0 nm range.

(rR) Measured by the KBr method using a Hitachi 260-10 infrared spectrophotometer.

[Particle dispersion power] (Calcium carbonate slurry) - A total of 250 g of the invention and tap water in a National MI mixer
Add calcium carbonate (light calcium carbonate manufactured by Takehara Chemical Industry Co., Ltd.) 2509 and mix for 2 minutes to prepare a 50% by weight slurry. Immediately thereafter, the slurry was transferred to a beaker, and the rotation speed was 50 using a Tokyo Keiki DV) I-B model meter.
Measure the viscosity (cps) at rpm, rotor No. 3-5. However, the concentration of the partially decomposed product of the invention is
The weight is 0.3 based on the total amount of 5009.

(Kaolin slurry) - Put 2009 of the partially decomposed product of this invention and tap water into a National MI mixer, add 3009 of kaolin [manufactured by Ueya Kaolin Kogyo (PI8)] powder and mix for 2 minutes to make 60 g of 15 slurry. Prepare. Immediately thereafter, the slurry is transferred to a beaker, and the viscosity is measured using a DV) I-B type meter manufactured by Tokyo Keiki at a rotational speed of 5 Orpm and a rotor number of 3 to 5. However, the concentration of the partially decomposed product of this invention is 0.3% by weight based on the total amount of 500g.

(Margins below) Table 4 The methods for measuring surface tension and emulsification duration are as follows.

[Measurement of Surface Tension] The surface tension of the invention products prepared in Examples was measured using a Dunuy surface tension meter at a temperature of 25° C. using pure water as a solvent.

[Measurement of Emulsification Duration] The emulsification duration of the product prepared in Example was measured by the following test method.

(Test method) -Pour a total of 709 samples of drug and tap water into a beaker,
Adjust pH to 7.0. Soybean oil (reagent manufactured by Kishida Kagaku Co., Ltd.) 309 was added and mixed for 5 minutes at 800 rpm using an HV-M homomixer manufactured by Tokushu Kika Kogyo Co., Ltd. Immediately after mixing, the emulsion is transferred to a colorimetric tube and left at room temperature, and the time until separation begins is defined as the emulsification duration. The emulsification duration was measured every 10 minutes until 1 hour after the start of standing, and thereafter every 1 hour. However, the concentration of the partially decomposed product of this invention added is 1.0% by weight based on the total amount.

Comparative example! (Preparation of Wheat Gluten 11S) The wheat gluten used in Examples 1 to 1O was used as it was as Comparative Samples No. 1 and L without being subjected to decomposition treatment.

Comparative Example 2 (Preparation of partially decomposed product of wheat gluten with alkali) Examples 1 to 9 were added to an aqueous solution too9 in which caustic soda 29 was dissolved.
! Add wheat gluten 209 used in step 0 and heat at 100°C.
After heating and stirring for 0 minutes, neutralize with hydrochloric acid and add pure water to a total amount of 200g.
Comparative device No. 2 was obtained.

The average molecular weight was 47,000.

Comparative Example 3 (Preparation of enzymatic partial decomposition product of wheat gluten) 0.1N of wheat gluten 209 used in Example 1-to
-Add to a flask containing 150g of hydrochloric acid solution, pH 1.5
An aqueous solution of was obtained. Add 0.29 pepsin to this and 37
The reaction was carried out at ℃ for 90 minutes. Thereafter, the mixture was neutralized with caustic soda and the total amount was adjusted to 2009 with pure water to obtain comparative sample No. 013. The average molecular weight of the partially decomposed product was 60,000.

Comparative Example 4 (Preparation of decomposed product by partial decomposition of wheat gluten with a reducing agent and subsequent partial decomposition with an enzyme) Wheat gluten 209 used in Examples 1 to 10 was added to 100 g of an aqueous solution in which sodium sulfite 49 was dissolved, 30℃
After stirring for 60 minutes at , hydrochloric acid was added to obtain an aqueous solution with a pH of 1.5, to which 0.29 pepsin was added and reacted at 37° C. for 90 minutes. After that, neutralize with caustic soda and completely ff with pure water.
12009 to obtain comparison tool No. 4.

The average molecular weight was 36,000.

Inventive products No. 1 to 20 of Examples of this invention, Comparative devices No. 1 to 4 of Comparative examples, and sucrose fatty acid ester which is a known quality improver [manufactured by Daiichi Kogyo Seiyaku (Aji), trade name: D
K-ester F-160 (HLB15), Comparison No.

5j Palmitic acid monoglyceride [manufactured by Taiyo Kagaku Co., Ltd., trade name: Sunsoft No. 8001. Comparison product No. 6
The following test examples were carried out using

Test Example 1 (Bread making test) A. Bread making method Bread was made using a National home bakery and left at a temperature of 25°C. The bread making conditions are shown below.

・Bread making machine・・・National Home Bakery-3
D-Br3 type/Ingredients Strong flour...2809 Sugar...179 Skim milk...69 Salt...59 Butter...tt9 Water... ...2109 Dry yeast...2.79・Bread making time・
...300 minutes However, each invention product and comparative device were mixed and added to the raw materials. Moreover, the addition concentration in the table is weight % based on strong flour.

B. Test results As a result of measuring bread volume, moisture content, its change over time, softness, and degree of starch aging, it was found that for invention products Nos. 1 to 20, which are examples of this invention, both without additives and in comparison. Compared to ingredients, it showed the same or better quality improvement effect. Typical examples are shown in Table 5 along with comparative examples.

The evaluation items in the table were measured as follows.

- Moisture content (%): Calculated from the difference in weight before and after drying at 105°C for 2 hours.

・Moisture content change (%): (moisture content during bread making) - (moisture content after standing) ・Softening crust (97cm): Using a rheometer manufactured by Fudo Kogyo (NRM-2010J, D-CW) ,
It was determined as tensile strength.

・Starch aging! (%): Calculated by determining the degree of gelatinization using the BAP method (F Biochemical Experimental Methods T9-Starch and Related Carbohydrate Experimental Methods [Gakkai Publishing Center]) using β-amylase and pullulanase.

(Margins below) Table 5 (Continued) In addition, the above invention! The results of using the partial decomposition product of No. 1 and No. 11 in combination with Sho v1 fatty acid ester or palmitic acid monoglyceride are also shown in Table 6 below.

C9 Consideration [Bread Volume] As shown in Test Nos. 2 to 17 above, by adding 0.5% by weight of the invention product of this invention, the bread volume was increased to 7% by weight.
~18% increase can be avoided, and the increase effect of each comparison product O
It is clearly soaked compared to ~8%.

Furthermore, as shown in Test Examples Nos. 18 to 21, it was found that the bread volume was further increased when used in combination with sucrose fatty acid ester and palmitic acid monoglyceride.

[Water retention and softness] Bread made using each invention product had a lower degree of decrease in water content than the blank or comparison product, and had a high water retention property. The softness has also been improved as well.

[Starch retrogradation degree] The retrogradation degree of the bread made using each invention product was clearly suppressed compared to the blank], and was visually 1 to 2.
Durability has improved over time.

Test Example 2 (Noodle manufacturing test) After the noodles are manufactured, the quality gradually deteriorates, and the texture and texture become worse. In addition, the tendency to separate becomes worse. Therefore, the effects of the products of the present invention were compared and studied.

A. Noodle making method: A predetermined amount of the sample was added to 99 grams of all-purpose wheat flour, 29 grams of salt, and 359 grams of water, and the resulting noodle dough was kneaded into a noodle dough about 1.2 x m thick using a noodle making roll. This noodle strip was cut into noodle strips using Kakuriki Tsuta No. 20, and the cut pieces were cut into lengths of about 30 cm and boiled for about 5 minutes at about 5°C.
stored in the refrigerator.

Thereafter, they were washed in boiling water for about 1 minute without stirring, and the state of separation was observed, and a sensitivity test was conducted at the same time.

B. Test Results Inventive products No. 1 to 2o, which are examples of the present invention, were all successful in terms of peeling and texture compared to the comparative products. Typical examples are shown in Table 7 along with comparative examples.

The concentration (%) in the table is the weight % of the sample relative to the wheat flour. The sensitivity test was conducted by 10 panelists, and the results are comprehensively summarized.

(The following is a blank space) (F) Effects of the Invention According to the quality improving agent of the present invention, it is possible to impart stickiness and fineness of texture when preparing the dough of various starchy foods, and
The water retention properties of the resulting starchy food can be significantly improved and excellent anti-aging properties can be imparted. And for example,
As for bread, the volume can be increased compared to conventional quality improving agents, and in combination with the above effects, it becomes possible to efficiently provide bread that maintains its softness for a long period of time. It is also effective for adjusting the dough of noodles, for example, and can provide noodles that maintain good loosening properties and texture for a long period of time due to anti-aging and water-retaining effects. Since the active ingredient, the partial decomposition product of grain protein, is food or food-like, it is extremely advantageous in that it is non-toxic and has improved safety as a food additive.
Moreover, it is inexpensive.

Therefore, the quality improver of the present invention is extremely useful as an additive for starchy raw materials.

[Brief explanation of the drawing]

FIGS. 1(a) to 1(d) are graphs illustrating pH neutralization curves for partial hydrolysates used in the present invention. (B) (C) IN HCl (ml) Figure (d) IN-HCl (ml)

Claims (1)

[Scope of Claims] (1) A partial decomposition product of grain protein, which has the following physical properties: (a) a weight average molecular weight (by gel filtration method) of 500 to 500;
(b) UV absorption λmax is around 260 to 280 nm, and infrared absorption is 1400, 1630 and 3400 cm.
(c) Isoelectric point is around ^-^1, 3.9 to 5.0
(d) pH buffering property (1N to lower the pH of 100ml of a 5% aqueous solution of this product from 6 to 2)
(requires 2 to 25 ml of hydrochloric acid); (e) is soluble in water and insoluble in methanol, ethanol, acetone, and ether; (f) is a pale yellow to reddish brown powder in appearance; (g)
Color develops due to xanthoprotein reaction and ninhydrin reaction. (h) Strong surface tension lowering ability (this product is added to pure water at 25°C for 0.00 min.
By adding 1% by weight, the surface tension of pure water increases by 50%.
dyne/cm (measured with a Dunui surface tension meter). (i) Strong emulsifying ability (by adding 1 g of this product, a water-soybean oil mixture containing at least 30% by weight of soybean oil)
Completely emulsify 0g (keep it uniformly emulsified for at least 10 minutes,
A quality improving agent for starchy foods comprising a substance characterized by: (meaning that it can be maintained preferably for 1 hour or more). (2) The partial decomposition product is produced by a combination of one or more of the following: (A) hydrolysis treatment with an alkali and (B) decomposition treatment using an acid, an enzyme, an oxidizing agent, or a reducing agent. The quality improver according to claim (1), which is a substance obtained by subjecting it to multi-stage partial decomposition treatment. (3) The partially decomposed product undergoes hydrolysis treatment with an alkali,
The quality improving agent according to claim 2, which is obtained by a two-stage partial decomposition treatment in combination with an acid hydrolysis treatment. (1) The quality improving agent according to any one of claims (1) to (3), wherein the grain is wheat gluten, corn gluten, or soybean protein. (5) The quality improving agent according to any one of claims (1) to (4), wherein the starchy food is bread or noodles. (6) The quality improver according to claim (5), wherein the starchy food is bread. (7) The quality improving agent according to claim (1), further comprising a polyhydric alcohol fatty acid ester type surfactant. (8) The quality improving agent according to claim (7), wherein the protein partial decomposition product and the polyhydric alcohol fatty acid ester type surfactant are blended in a weight ratio of 1:6 to 6:1. (9) The polyhydric alcohol fatty acid ester type surfactant is
The quality improving agent according to claim 8, which is a sucrose fatty acid ester and/or a glycerin fatty acid ester. (10) The quality improving agent according to claim (1) or (7), which is used by adding 0.01 to 5% by weight to the starchy food material.