JP7664580B2 - Bread dough mix - Google Patents

Description

The present invention relates to a flour mix for bread dough, bread dough using the flour mix, breads obtained by baking the bread dough, and a method for producing the breads.

Bread is mainly composed of starch, and its moisture content is in the range of 30-60% (w/w), which is the range at which starch easily deteriorates. Therefore, the starch that gelatinizes when baked is prone to deterioration over time, and the bread becomes dry during storage. Various improvements have been made to improve this.

First, a well-known method is to replace part of wheat flour, the main ingredient of bread, with pregelatinized starch in order to prevent dryness caused by aging (see, for example, Patent Document 1). This is because when pregelatinized starch is used as an ingredient in bread dough, the amount of water added is increased, improving water retention and maintaining a soft texture. However, if pregelatinized starch is used in large amounts in bread dough, the dryness caused by aging can be prevented, but stickiness occurs during the bread dough production process, making it difficult to work with, and the texture of baked bread becomes chewy and difficult to melt in the mouth. To improve this, it has been proposed to use pregelatinized starch that has been made less prone to swelling by crosslinking (see, for example, Patent Document 2), or to use hydroxypropyl starch or acetylated starch that has been given resistance to aging by previously substituting the hydroxyl groups of the starch glucose residues with propylene oxide or acetic acid (see, for example, Patent Document 3). It has also been proposed to combine pregelatinized starch with hydroxypropyl starch or acetylated starch to give bread a chewy, mochi-like texture (Patent Document 4).

However, breads baked by partially substituting wheat flour with the above-mentioned pregelatinized starch or substituted modified starch have the drawback that, although they maintain a soft texture, they cannot avoid a chewy texture. Therefore, in order to achieve both a soft texture and a crisp texture, the use of oxidized starch (Patent Document 6) and dextrins (Patent Document 7) has been proposed.

However, because oxidized starch and dextrin are made by partially decomposing starch into smaller molecules, they do not impart the chewy texture that occurs when pregelatinized starch or substituted modified starch is used, and can provide bread that is crisp. However, they do not adequately prevent dryness caused by aging over time, and there is room for improvement.

Japanese Patent Application Publication No. 59-175845 Japanese Patent Application Publication No. 4-91744 Japanese Patent Application Publication No. 3-87135 Japanese Patent Application Publication No. 10-295253 JP 2005-52014 A JP 2009-273421 A Japanese Patent Application Publication No. 5-292870

The objective of the present invention is to provide breads with improved stability over time and texture, to provide bread dough or a flour mix for bread dough for providing such breads, and to provide a method for producing such breads.

The inventors conducted various investigations to solve these problems, and discovered that the above problems could be solved by using a mixed flour containing specific types of hydroxypropylated starch, gelatinized starch, oxidized starch, and starch hydrolysates in specific ratios, which led to the completion of the present invention.

The present invention mainly consists of four inventions. The first invention is a bread dough mix flour as described below in [1] to [9].
[1] A flour mix for bread dough comprising (A) hydroxypropylated starch, (B) pregelatinized starch, (C) a starch hydrolysate, and (D) an oxidized starch, the blending amounts of which satisfy the following (a) and (b):
(a) (A)>(B)>(C)>(D),
(b) [(A)+(B)]:[(C)+(D)]=[2-10]:[1].
[2] The flour mix for bread dough according to the above-mentioned [1], wherein (A) is a hydroxypropylated starch having a DS of 0.03 to 0.2, the hydroxypropylated starch being made from one or more raw materials selected from the group consisting of waxy tapioca starch, waxy corn starch, and waxy potato starch.
[3] The flour mix for bread dough according to [1] or [2] above, wherein (A) is a hydroxypropylated starch having a sedimentation volume of 6.0 to 10.0.
[4] The flour mix for bread dough according to any one of [1] to [3] above, wherein (B) is a gelatinized product of hydroxypropylated crosslinked starch having a cold water swelling degree of 15 to 75.
[5] The bread dough mix flour according to any one of [1] to [4] above, wherein (C) is a starch hydrolyzate having a DE of 1 to 20.
[6] The flour mix for bread dough according to any one of [1] to [5] above, wherein (D) is an oxidized starch having a 20% (w/v) viscosity at 30°C of 10 to 100 mPa·s.
[7] The flour mix for bread dough according to any one of [1] to [6] above, wherein (D) is an oxidized starch made from potato starch.
[8] A bread dough mix flour according to any one of [1] to [7] above, used in a ratio of 2 to 30 parts by mass per 100 parts by mass of cereal flour.
[9] A bread dough mix flour comprising 2 to 30 parts by mass of the bread dough mix flour according to any one of [1] to [8] above out of 100 parts by mass of cereal flour.

The second invention is the bread dough described below in [10], which uses the bread dough mix flour of the first invention.
[10] Bread dough comprising the flour mix for bread dough according to any one of [1] to [9] above.

The third invention relates to breads as described below in [11], which are obtained by baking the bread dough of the second invention.
[11] Breads obtained by baking the dough according to [10] above.

The fourth invention is a method for producing bread according to the third invention, as described below in [12].
[12] A method for producing bread, comprising mixing 2 to 30 parts by mass of the mixed flour described in any one of [1] to [7] above in 100 parts by mass of cereal flour, adding auxiliary ingredients and kneading the mixture, and then carrying out a fermentation process and a baking process.

The present invention makes it possible to provide breads with improved stability over time and texture.

Hydroxypropylated starch generally refers to a hydroxyl group-substituted processed starch obtained by reacting propylene oxide with starch in a standard manner, and in the present invention, unless otherwise specified, includes hydroxypropylated crosslinked starch obtained by reacting a crosslinking agent such as sodium trimetaphosphate or phosphorus oxychloride in a standard manner simultaneously or at a different time with the hydroxypropylation reaction. The hydroxypropylated starch used in the present invention may be obtained from any starch, such as rice starch, corn starch, tapioca starch, potato starch, sweet potato starch, sago starch, pea starch, wheat starch, or the starches of these waxy varieties, but it is more preferable to use waxy corn, waxy tapioca, or waxy potato starch as the raw material. In addition, the above-mentioned degree of substitution and degree of crosslinking are not particularly limited, but from the viewpoint of obtaining the effects of the present invention more efficiently, the degree of substitution (the degree of substitution when all three free hydroxyl groups of the glucose residues constituting the starch are substituted is 3) is preferably in the range of 0.03 to 0.2, more preferably in the range of 0.07 to 0.18, and even more preferably in the range of 0.09 to 0.18. In addition, when using a starch that is crosslinked in addition to being substituted by hydroxypropyl, the degree of crosslinking is preferably low, and in terms of the sedimentation volume of the hydroxypropylated crosslinked starch, it is preferably 6.0 to 10 ml, more preferably 8.0 to 10 ml, and even more preferably 9.0 to 10 ml.

The sedimentation volume in the present invention is a well-known general analytical item, and is measured as follows. First, 0.15 g (solid content equivalent) of starch sample is weighed into a test tube, and 15 ml of a previously prepared reagent (adjusted with 26% ammonium chloride, 10% zinc chloride, and 64% water) is poured into it. Next, the starch material in the starch sample in the test tube is uniformly dispersed using a bench vibrator, and the tube is immediately placed in a boiling bath and heated for 10 minutes, and then cooled to 25-35°C. The starch sample in the test tube is dispersed again using a bench vibrator, and poured into a 10-ml graduated cylinder up to the 10-ml mark. After leaving the cylinder at 25°C for 20 hours, the sediment scale is read, and this value is taken as the sedimentation volume. The value of the sedimentation volume is smaller for starches with a higher degree of crosslinking (highly crosslinked starch).

Pregelatinized starch generally refers to starch that has been gelatinized by adding moisture and heating, and what is commonly sold as pregelatinized starch is the product that has been further dried. Pregelatinized starch is also called instant starch because it absorbs moisture and regelatinizes when dispersed in liquid such as water, and is often used in instant soups and instant drinks to impart viscosity. There are no limitations on the raw material type or processing level of the pregelatinized starch used in the present invention, but from the viewpoint of more efficiently obtaining the effects of the present invention, it is preferable to use crosslinked processed starch as the raw material rather than unprocessed starch, and among crosslinked starches, hydroxypropylated crosslinked starch is more preferable. The cold water swelling degree is preferably 15 to 75 ml, and more preferably 20 to 75 ml.

The method for measuring the cold water swelling degree of pregelatinized starch is as follows. First, 2.0 g of a starch sample (based on solids content) is uniformly dispersed in 50 ml of water, and this suspension is placed in a 100 ml measuring cylinder, adjusted to 100 ml with water, and left to stand for 24 hours. After that, the volume (ml) of the cloudy layer is measured, and this value is taken as the cold water swelling degree (ml). The higher the degree of crosslinking, the smaller the swelling degree.

Starch hydrolysates, also known as dextrins, are obtained by hydrolyzing starch with an enzyme such as α-amylase or an acid such as hydrochloric acid. There are no limitations on the raw material for the starch hydrolysates used in the present invention, but it is preferable to use at least tapioca starch, corn starch, waxy corn starch, or sweet potato starch as the raw material. There are no limitations on the degree of hydrolysis, but the DE (abbreviation for Dextrose Equivalent; DE is 100 when all starch is hydrolyzed down to glucose units) should be 1 to 20, and more preferably 2 to 18, or even 4 to 16. The DE referred to here is a measurement value obtained by the Willstätter-Schudel method.

Oxidized starch generally refers to processed starch obtained by reacting starch with an oxidizing agent such as sodium hypochlorite in a standard manner, and it is presumed that the oxidizing agent generates carboxyl groups and carbonyl groups in the molecule and depolymerizes the molecule. The oxidized starch used in the present invention is not particularly limited, but from the viewpoint of more efficiently obtaining the effects of the present invention, a relatively highly oxidized one is preferable, and in terms of 20% (w/v) viscosity at 30°C, when measured with a B-type viscometer (BM type, rotor No. 1, 60 rpm, 30 seconds), it is 10 to 500 mPa·s, more preferably 10 to 100 mPa·s, and even more preferably 10 to 40 mPa·s. In addition, there is no limitation on the type of raw starch for the oxidized starch used in the present invention, but from the viewpoint of more efficiently obtaining the effects of the present invention, it is preferable that the raw starch is one or more types selected from the group consisting of potato starch, waxy corn starch, and tapioca starch, and potato starch is more preferable.

The bread dough mix flour of the present invention is a composition containing the above-mentioned hydroxypropylated starch, pregelatinized starch, oxidized starch, and starch hydrolysate as essential ingredients. However, if pregelatinized starch is used in large amounts, the texture of the resulting bread is soft but has a strong chewy feeling, and if the amount of pregelatinized starch used is insufficient, the aging resistance is not sufficient. Furthermore, even if it is attempted to replace it with hydroxypropylated starch, it cannot be completely replaced from the viewpoint of aging resistance. Therefore, although these two are essential ingredients, it was found that one condition is that the amount of pregelatinized starch must not exceed the amount of hydroxypropylated starch used. Furthermore, although the chewy feeling can be improved to some extent by using these two in combination, it is still difficult to achieve both aging resistance and chewy feeling. Therefore, when the improvement of aging resistance while eliminating the chewy feeling as much as possible was examined, it was found that the aging resistance can be improved by using a certain amount of starch hydrolysate in combination. However, it was found that if more than a certain amount of starch hydrolysate is used, the dough becomes sticky during bread making, which not only reduces workability but also deteriorates the texture, so it cannot be used excessively, and another condition is that the amount used must not exceed that of pregelatinized starch. A comparative study was then conducted on the use of oxidized starch in addition to hydroxypropylated starch, pregelatinized starch, and starch hydrolysates, and it was found that while it is difficult to maintain a soft texture using oxidized starch alone, the texture and aging resistance are significantly improved by using a small amount of it as part of the starch substitute for wheat flour. However, it was also found that the texture deteriorates if the amount of oxidized starch used exceeds the amount of starch hydrolysate used. Therefore, it can be said that the ideal amount to use of these four essential ingredients should be set in the following order: hydroxypropylated starch > pregelatinized starch > starch hydrolysate > oxidized starch.

The composition ratio of (A) hydroxypropylated starch, (B) pregelatinized starch, (C) starch hydrolysate, and (D) starch hydrolysate must satisfy the above-mentioned usage amount conditions and must be at least in the range of [A+B]:[C+D]=[2-10]:[1] parts by mass.

The bread dough flour mix of the present invention is ultimately intended for producing breads, and is therefore used together with wheat flour or other grain flour that forms a gluten film when kneaded. When producing bread, the manufacturer may select the grain flour such as wheat flour of their choice and mix it with the bread dough flour mix of the present invention for use, or it may be mixed in advance with the bread dough flour mix consisting of the above-mentioned starch group and used as a bread dough flour mix containing wheat flour or other grain flour. It is preferable to use the bread dough flour mix of the present invention in place of 2 to 30 parts by mass of 100 parts by mass of grain flour.

The wheat flour and other cereal flours mentioned above may be any that are used in the manufacture of ordinary breads, and whole wheat flour, rye flour, corn flour, graham flour, rice flour, starch, barley, amaranth, quinoa, etc. may be used in combination with or substituted for them. From the viewpoint of bread-making, however, it is preferable to use wheat flour as the main component, and the substitution rate should be 30% (w/w) or less, preferably about 5 to 10% (w/w) of the wheat flour. Note that the "cereal flour" referred to in the present invention also includes starches other than hydroxypropylated starch, pregelatinized starch, and oxidized starch, which are essential components of the present invention.

The bread dough of the present invention is obtained by adding auxiliary ingredients including water to the above-mentioned bread dough mix flour of the present invention, kneading, and then going through a fermentation process. Here, auxiliary ingredients generally refer to all ingredients that can be added as ingredients when making bread, and examples of such auxiliary ingredients include water, milk, eggs, butter, margarine, shortening, olive oil, lard, processed oils and fats, sugar, brown sugar, glucose, oligosaccharides, isomerized sugar, starch syrup, honey, sugar alcohol, skim milk powder, whole milk powder, salt, yeast, emulsifiers, dietary fiber, gluten, spices, coloring agents, yeast food, thickeners, cacao, cheese, nuts, herbs, fruits, matcha, black tea, cocoa, etc.

The bread of the present invention is made by baking the above-mentioned bread dough, and the type of bread is not particularly limited, and any bread that is fermented with yeast and baked, such as white bread, French bread, buns, table rolls, croissants, Danish pastries, bean-jam buns, cream buns, yeast donuts, etc., is acceptable, but the form of bread in which the effects of the present invention are most effectively exhibited is white bread. In particular, when white bread is sliced and made into sandwiches with ingredients, it is often stored and displayed in a refrigerated state at home or in a store, and the effects of the present invention are more effectively exhibited in bread that is stored in such a refrigerated state for long periods of time.

The present invention will be explained in detail and specifically below by presenting experimental examples, but the present invention is not limited to these experimental examples.

A part of the wheat flour in the basic recipe for bread in [Table 1] was replaced with one or more of (A) hydroxypropylated starch, (B) pregelatinized starch, (C) starch hydrolysate, and (D) oxidized starch (hereinafter referred to as "starch, etc."), and bread was made according to the procedure in [Table 2]. The bread-making suitability was evaluated by four experts who are involved in bread making on a daily basis, and the melt-in-the-mouth evaluation was performed by 10 well-trained panelists who tasted the bread 24 hours after baking (at room temperature). The aging resistance (sustained moistness) was evaluated by 10 well-trained panelists who tasted the bread 24 hours after baking and 48 hours after baking (at room temperature). The sensory evaluation was performed by each panelist using a 5-point scale (the higher the score, the better) according to the evaluation criteria shown in [Table 3] and [Table 4], and the average of the 10 panelists was used. In addition, the suitability for bread making was determined by consensus among all four manufacturers (Table 5). The overall evaluation was done using the evaluation results for each item and ranking according to the criteria in [Table 6] (◎, 〇, △, ×).

The oxidized starches No. 1 to 4 used in the subsequent experiments were prepared as follows. First, a slurry of 100 parts of starch dispersed in 130 parts of water was adjusted to pH 7 to 8, and the required amount of sodium hypochlorite (2 to 4%) was added to initiate the reaction at 35°C. When the desired viscosity was reached (approximately 1 to 8 hours), the mixture was neutralized with sulfuric acid to stop the reaction, and then washed with water, dehydrated, and dried to obtain oxidized starches No. 1 to 4.

Hydroxypropylated starch (hydroxypropylated phosphate cross-linked starch) No. 1 to 4 used in the following experiments were prepared as follows. First, a slurry of 10 parts of sodium sulfate and 100 parts of starch dispersed in 130 parts of water was adjusted to pH 11 to 12, and the required amount of propylene oxide (6 to 10%) was added and reacted at 40°C for 20 hours. Next, the required amount of sodium trimetaphosphate (0.02% to 1%) was added and reacted at 40°C for 5 hours. After the reaction, the slurry was neutralized with sulfuric acid, washed with water, dehydrated, and dried to obtain hydroxypropylated phosphate cross-linked starch No. 1 to 4.

The gelatinized starches No. 1 to 4 used in the subsequent experiments were prepared as follows. First, a slurry of 10 parts of sodium sulfate and 100 parts of starch dispersed in 130 parts of water was adjusted to pH 11 to 12, and the required amount of propylene oxide (8 to 10%) was added and reacted at 40°C for 20 hours. Next, the required amount of phosphorus oxychloride (0.04 to 0.1%) was added and reacted at 40°C for 1 hour. After the reaction, the slurry was neutralized with sulfuric acid and washed with water to obtain hydroxypropylated phosphate cross-linked starch, and the aqueous suspension was gelatinized (drum dried) to obtain gelatinized starches No. 1 to 4.

As shown in Table 7 above, when the amount of pregelatinized starch used was greater than the amount of hydroxypropylated starch used, the moistness of the baked bread remained for a long time (it was resistant to aging), but its suitability for bread-making deteriorated (the dough became difficult to handle). Therefore, it was decided to consider a different blend.

As shown in Table 8, the combination of hydroxypropylated starch and alpha-starch did not provide sufficient moistness or resistance to aging. The use of starch hydrolysates in combination was then investigated, and although there was a tendency for the melt-in-the-mouth texture, moistness, and resistance to aging to improve, when the amount used exceeded that of alpha-starch, the bread-making suitability deteriorated drastically. Therefore, it was decided to further consider a different formulation.

As shown in Table 9 above, when the use of oxidized starch instead of starch hydrolysates was examined, no dramatic improvement in effect was seen when oxidized starch was used alone, and increasing the amount added actually worsened retrogradation resistance. However, when used in combination with starch hydrolysates, melt-in-the-mouth texture and retrogradation resistance improved dramatically. However, retrogradation resistance worsened when the amount of oxidized starch used exceeded the amount of starch hydrolysates used. Specifically, it was found that it is desirable to use hydroxypropylated starch and pregelatinized starch in a range where the total of the starch hydrolysates and oxidized starch is 1, with the four components considered as essential components.

As shown in Table 10 above, when the appropriate replacement ratios of the four components in 100 parts by weight of wheat flour were examined, it was found that the evaluation was poor when 31.5 parts by weight of 100 parts by weight of wheat flour was replaced, so it was found that it is desirable to aim for a replacement of up to 30 parts by weight of 100 parts by weight of wheat flour.

As shown in Table 11 above, when the type of starch used as the raw material for oxidized starch was examined, it appeared to be significantly affected by the viscosity of a 20% (w/w) solution, and the expected effect was not fully achieved with oxidized starch with a viscosity of more than 1,000 mPa·s.

As shown in Table 12 above, when the preferred DE of starch hydrolysates was investigated, most starch hydrolysates showed improved melting in the mouth and resistance to retrogradation. However, starch hydrolysates with a DE of 25 or more showed very good melting in the mouth like other starch hydrolysates and were evaluated as having a certain level of resistance to retrogradation, but were not suitable for bread making.

As shown in Table 13 above, when we investigated the usability of hydroxypropylated starch made from starches other than glutinous tapioca starch, we found that it can be used because it has good melt-in-the-mouth texture, moistness, and bread-making properties, almost the same as when glutinous tapioca starch is used.

As shown in Table 14 above, when we investigated the usability of pregelatinized starch made from starches other than potato starch, we found that it was usable because it had good melt-in-the-mouth texture, moistness, and bread-making properties, almost the same as when potato starch was used.

A loaf of bread made with the present invention (bread of Test 10) and a loaf of bread not using the mix of the present invention were prepared, each sliced to a thickness of 1 cm, and sandwiched with lettuce and ham. Both were stored in a refrigerator (4°C) for 24 hours, and the sandwich made with the loaf of bread made with the present invention retained its moist texture even after 24 hours and had a good melt-in-the-mouth texture.

Claims (12)

(A) hydroxypropylated starch,
(B) pregelatinized starch,
A flour mix for bread dough comprising (C) a starch hydrolysate and (D) an oxidized starch, the blending amounts of which satisfy the following (a) and (b):
(a) (A)>(B)>(C)>(D),
(b) [(A)+(B)]:[(C)+(D)]=[2-10]:[1]. The flour mix for bread dough according to claim 1, wherein (A) is a hydroxypropylated starch having a DS of 0.03 to 0.2, the hydroxypropylated starch being made from one or more ingredients selected from the group consisting of waxy tapioca starch, waxy corn starch, and waxy potato starch. The flour mix for bread dough according to claim 1 or 2, wherein (A) is a hydroxypropylated starch having a sedimentation volume of 6.0 to 10.0. The bread dough flour mix according to any one of claims 1 to 3, wherein (B) is a gelatinized product of hydroxypropylated crosslinked starch having a cold water swelling degree of 15 to 75. The flour mix for bread dough according to any one of claims 1 to 4, wherein (C) is a starch hydrolysate having a DE of 1 to 20. The bread dough flour mix according to any one of claims 1 to 5, wherein (D) is an oxidized starch having a 20% (w/v) viscosity at 30°C of 10 to 100 mPa·s. The bread dough flour mix according to any one of claims 1 to 6, wherein (D) is an oxidized starch made from potato starch. The bread dough mix flour according to any one of claims 1 to 7, used in a ratio of 2 to 30 parts by mass per 100 parts by mass of cereal flour. A flour mix for bread dough comprising 2 to 30 parts by mass of the flour mix for bread dough according to any one of claims 1 to 8 per 100 parts by mass of cereal flour. Bread dough comprising the flour mix for bread dough according to any one of claims 1 to 9. Breads made by baking the dough according to claim 10. A method for producing bread, comprising mixing 2 to 30 parts by mass of the mixed flour according to any one of claims 1 to 7 in 100 parts by mass of grain flour, adding auxiliary ingredients, kneading, and carrying out a fermentation process and a baking process.