Agent for improving quality of bread, and method for improving quality of bread

Abstract

Provided is a technology for improving the quality of bread produced by using a frozen bread dough.　The present technology provides an agent for improving the quality of bread produced by using a frozen bread dough, the agent comprising at least one component selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C.

Description

Bread improver and bread improver method

[0001] The present technology relates to a bread improver. More specifically, the present technology relates to a bread improver for bread produced using frozen bread dough, frozen bread dough, bread, a method for producing bread, and a method for improving bread.

[0002] Various techniques using enzymes have been developed to improve the quality of bread. For example, Patent Document 1 proposes a technique for improving the physical properties of dough, such as dough unity and dough extensibility, by producing dough such as bread dough by adding (A) oxidoreductase, (B) metallo-yeast, (C) polyglutamic acid and / or phospholipase, and (D) hemicellulase and / or glycosyltransferase to dough ingredients.

[0003] Furthermore, with the development of freezing technology, the production and sale of bread using frozen dough and the distribution of frozen dough itself have become popular, but there has been a problem in that bread made using frozen dough is of inferior quality compared to bread made without going through the freezing process.

[0004] Various proposals have also been made regarding techniques for improving the quality of bread made using frozen dough. For example, Patent Document 2 discloses a technique for improving the expansion rate retention rate, specific volume retention rate, taste, and quality of a product obtained by thawing, fermenting, and steaming frozen dough by using 100 parts of protein powder, 4 to 6 parts of glucosylstevioside, 9 to 1 part of α-amylase, 4 to 6 parts of glucose oxidase, 2 to 4 parts of xylanase, 7 to 9 parts of trimethylethyl lactone, 9 to 11 parts of an amphoteric polymer, and 5 to 7 parts of γ-polyglutamic acid in the frozen dough.

[0005] Japanese Patent Application Publication No. 2021-153525 CN115918888A

[0006] As mentioned above, many techniques for improving the quality of bread and bread made using frozen dough are being developed, but the reality is that further technological improvements are desired.

[0007] Therefore, the main object of this technology is to provide a technology for improving the quality of bread made using frozen dough.

[0008] The present technology first provides a bread improver produced using frozen bread dough, which contains one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C. The present technology also provides frozen bread dough using the bread improver according to the present technology. The present technology further provides bread using the frozen bread dough according to the present technology.

[0009] The present technology next provides a method for producing bread using frozen dough, and a method for improving bread produced using frozen dough, which includes a dough preparation step of preparing dough using one or more ingredients selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C. The present technology also provides a method for producing bread using frozen dough, and a method for improving bread produced using frozen dough, which includes a freezing step of freezing dough prepared using one or more ingredients selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C.

[0010] Preferred embodiments for carrying out the present technology will be described below. Note that the embodiments described below are examples of typical embodiments of the present technology, and the scope of the present technology should not be construed as being narrow.

[0011] 1. Bread improver The bread improver according to the present technology contains one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C. In this technology, by using one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C in frozen bread dough, it is possible to improve the quality of bread produced using the frozen bread dough. In this technology, "improving the quality of bread produced using frozen bread dough" is a concept that includes not only suppressing the deterioration in quality of bread that occurs as a result of the freezing process and improving the quality to the same level as bread produced without the freezing process, but also improving the quality of bread that does not deteriorate even after the freezing process to a level higher than the quality of bread produced without the freezing process.

[0012] Specific examples of improving the quality of bread include increasing volume, reducing hardness (improving softness), inhibiting aging, improving elasticity, improving cohesiveness, improving texture, and improving color, and the present technology can be particularly effective in increasing volume and reducing hardness.

[0013] More specifically, as demonstrated in the Examples described below, the use of one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C not only increases the volume of bread produced using frozen dough and / or inhibits hardening due to the freezing process, but also makes it possible to produce bread that is as soft as or softer than bread produced without a freezing process. Furthermore, it prevents the loss of volume and hardening of bread caused by prolonged frozen storage, and even when the frozen storage period is prolonged, it is possible to increase the volume to the same as or softer than bread produced without a freezing process and / or produce bread that is softer than bread produced without a freezing process. In particular, when modifying bread that will be stored frozen for long periods of time, a higher modification effect can be achieved by using two or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C, and among these, an even higher modification effect can be achieved by using two or more components selected from 4-α-glucanotransferase, lipase, and vitamin C, and an especially high modification effect can be achieved by using the three components 4-α-glucanotransferase, lipase, and vitamin C.

[0014] The modifying agent according to the present technology can be used to modify any type of bread as long as it is made using frozen dough, but the present technology is particularly suitable for use in bread made without yeast. Below, each component that can be used in the present technology will be described in detail.

[0015] (1) 4-α-Glucanotransferase The 4-α-glucanotransferase (EC 2.4.1.25) used in the present technology is an enzyme that catalyzes a chemical reaction in which a portion of 1,4-α-glucan is transferred to another portion of a carbohydrate such as glucose or 1,4-α-D-glucan. The 4-α-glucanotransferase used in the present technology is an enzyme that acts on polysaccharides and oligosaccharides having α-1,4 glycosidic bonds and transfers maltotriose units to saccharides, and may also have other functions, and the type, origin, etc. of the enzyme are not particularly limited.

[0016] The 4-α-glucanotransferase may be derived from either a plant or a microorganism. Examples of plant-derived 4-α-glucanotransferase include 4-α-glucanotransferase derived from potato (Solanum tuberosum L.) tubers. Examples of microorganism-derived 4-α-glucanotransferase include 4-α-glucanotransferase derived from actinomycetes (limited to Streptomyces avermitilis, Streptomyces cinnamoneus, Streptomyces griseus, Streptomyces thermoviolaceus, and Streptomyces violaceoruber) or bacteria (Agrobacterium radiobacter). radiobacter), Arthrobacter spp., Bacillus spp., Erwinia spp., Geobacillus pallidus, Geobacillus stearothermophilus, Gluconobacter oxydans, Leuconostoc mesenteroides, Paenibacillus alginolyticus, Pimelobacter spp., Protaminobacter spp., Pseudomonas spp., Serratia spp., Sporosarcina globispora Examples of suitable 4-α-glucanotransferases include those derived from the genera Bacillus globispora and Thermus, and Aeribacillus pallidus.

[0017] These 4-α-glucanotransferases may be used alone or in combination of two or more.

[0018] In the present technology, it is particularly preferable to use a 4-α-glucanotransferase derived from a microorganism as the 4-α-glucanotransferase, it is more preferable to use a 4-α-glucanotransferase derived from Aeribacillus, and it is even more preferable to use a 4-α-glucanotransferase derived from Aeribacillus pallidus (including the species formerly known as Geobacillus pallidus).

[0019] Here, "4-α-glucanotransferase derived from Aeribacillus pallidus" means a 4-α-glucanotransferase produced by a microorganism classified as Aeribacillus pallidus (whether a wild-type strain or a mutant strain), or a 4-α-glucanotransferase obtained by genetic engineering techniques using a 4-α-glucanotransferase gene. Therefore, a recombinant produced by a host microorganism into which a 4-α-glucanotransferase gene obtained from Aeribacillus pallidus (or a modified version of said gene) has been introduced also falls under the category of "4-α-glucanotransferase derived from Aeribacillus pallidus (including that formerly known as Geobacillus pallidus)."

[0020] The 4-α-glucanotransferase used in the present technology can be prepared from the culture medium of a microorganism or plant from which the 4-α-glucanotransferase is derived. Specific preparation methods include methods of recovering 4-α-glucanotransferase from the culture medium or cells of the microorganism or plant. For example, when using a 4-α-glucanotransferase-secreting microorganism, the cells can be recovered from the culture medium in advance by filtration, centrifugation, or the like, as necessary, and the enzyme can then be separated and / or purified. Furthermore, when using a 4-α-glucanotransferase-nonsecreting microorganism or plant, the cells or plant can be recovered from the culture medium in advance by pressure treatment, ultrasonic treatment, or the like, to extract the enzyme, and the enzyme can then be separated and / or purified. The enzyme separation and / or purification method can be any known protein separation and / or purification method, without any particular limitation. Examples include centrifugation, UF concentration, salting out, and various chromatography methods using ion exchange resins, etc. The isolated and / or purified enzyme can be powdered by a drying method such as freeze-drying or vacuum drying, or can be powdered using an appropriate excipient and / or drying aid in the drying method. The isolated and / or purified enzyme can also be liquefied by adding an appropriate additive and sterilizing by filtration.

[0021] In the present technology, commercially available 4-α-glucanotransferase can also be used, and a preferred example of a commercially available product is 4-α-glucanotransferase (derived from Aeribacillus pallidus (formally Geobacillus pallidus)) manufactured by Amano Enzyme Inc.

[0022] In the present technology, the content of 4-α-glucanotransferase in the modifying agent is not particularly limited as long as it does not impair the action and effect of the present technology. The lower limit of the content of 4-α-glucanotransferase in the modifying agent can be, for example, 1 ppm or more, 10 ppm or more, 30 ppm or more, preferably 60 ppm or more, more preferably 80 ppm or more, even more preferably 100 ppm or more, and still more preferably 120 ppm or more in bread dough.

[0023] The upper limit of the content of 4-α-glucanotransferase in the modifier can be, for example, 3000 ppm or less, 1000 ppm or less, 600 ppm or less, preferably 500 ppm or less, more preferably 400 ppm or less, even more preferably 350 ppm or less, and even more preferably 250 ppm or less in the bread dough.

[0024] The content of 4-α-glucanotransferase in the modifying agent according to the present technology can be freely set as long as it does not impair the effects of the present technology. The content of 4-α-glucanotransferase can be set to, for example, 0.0023 mU or more per 1 g of bread dough, and from the viewpoint of further enhancing the bread modifying effect, the content can be set to preferably 0.011 mU or more, more preferably 0.025 mU or more, 0.01 mU or more, 0.1 mU or more, 1 mU or more, 10 mU or more, 50 mU or more, 100 mU or more, 200 mU or more, even more preferably 225 mU or more, 300 mU or more, and even more preferably 405 mU or more.

[0025] The upper limit of the amount of 4-α-glucanotransferase contained is not particularly limited as long as it does not impair the effects of the present technology, and can be set to, for example, 450 U or less, 400 U or less, 300 U or less, 200 U or less, 100 U or less, 90 U or less, 80 U or less, 70 U or less, 60 U or less, 50 U or less, 45 U or less, 30 U or less, 20 U or less, 10 U or less, 5 U or less, 3 U or less, 1 U or less, 0.9 U or less, 0.6 U or less, or 0.4 U or less per 1 g of bread dough.

[0026] In this technology, the 4-α-glucanotransferase activity is a value measured by the 4-α-glucanotransferase activity measurement method described in the Examples below, and one unit (1 U) is defined as the amount of enzyme that produces 1 μmol of glucose per minute when treated with maltotetraose as a substrate at pH 6.5 and 40°C.

[0027] (2) β-amylase β-amylase (EC 3.2.1.2) that can be used in the present technology is an exo-enzyme that sequentially degrades α-1,4 glycosidic bonds in starch starting from the non-reducing end with maltose (malt sugar) units. β-amylase that can be used in the present technology may also be an enzyme that has other functions as long as it has β-amylase activity.

[0028] The origin of the β-amylase that can be used in the present technology is not particularly limited, and one or more types of β-amylase derived from microorganisms or plants such as soybeans can be used in any combination. Examples of β-amylase derived from microorganisms include β-amylases derived from the genus Bacillus (e.g., Bacillus flexus, Bacillus megaterium, Bacillus polymyxa, Bacillus circulans, etc.), Streptomyces sp., and Pseudomonas sp. In the present technology, it is particularly preferable to use a β-amylase derived from a microorganism as the β-amylase, more preferably a β-amylase derived from the genus Bacillus, and even more preferably a β-amylase derived from Bacillus flexus.

[0029] Here, "β-amylase derived from Bacillus flexus" means a β-amylase produced by a microorganism classified as Bacillus flexus (whether a wild-type strain or a mutant strain), or a β-amylase obtained by genetic engineering techniques using a β-amylase gene. Therefore, a recombinant produced by a host microorganism into which a β-amylase gene obtained from Bacillus flexus (or a modified version of said gene) has been introduced also falls under the category of "β-amylase derived from Bacillus flexus."

[0030] The β-amylase used in the present technology can be prepared from the culture solution of the microorganism or plant from which the β-amylase is derived. Specific preparation methods include methods of recovering β-amylase from the culture solution or cells of the microorganism or plant. For example, when a β-amylase-secreting microorganism is used, the cells can be recovered from the culture solution in advance by filtration, centrifugation, or the like, as necessary, and the enzyme can then be separated and / or purified. Furthermore, when a β-amylase-nonsecreting microorganism or plant is used, the cells or plant can be recovered from the culture solution in advance by pressure treatment, ultrasonic treatment, or the like, and the enzyme can then be extracted and / or separated and / or purified. The enzyme separation and / or purification method can be any known protein separation and / or purification method, without any particular limitation. Examples of such methods include centrifugation, UF concentration, salting out, and various chromatography methods using ion exchange resins, etc. The isolated and / or purified enzyme can be powdered by a drying method such as freeze-drying or vacuum drying, or can be powdered using an appropriate excipient and / or drying aid in the drying method. The isolated and / or purified enzyme can also be liquefied by adding an appropriate additive and sterilizing by filtration.

[0031] In the present technology, commercially available β-amylase can also be used, and a preferred example of a commercially available β-amylase is β-amylase (derived from Bacillus flexus) manufactured by Amano Enzyme Inc.

[0032] In the present technology, the content of β-amylase in the modifying agent is not particularly limited as long as it does not impair the action and effect of the present technology. The lower limit of the content of β-amylase in the modifying agent in bread dough can be, for example, 0.1 ppm or more, 0.5 ppm or more, 1 ppm or more, 5 ppm or more, preferably 15 ppm or more, and more preferably 20 ppm or more.

[0033] The upper limit of the β-amylase content in the modifier can be, for example, 6000 ppm or less, 3000 ppm or less, 1000 ppm or less, 300 ppm or less, preferably 250 ppm or less, and more preferably 200 ppm or less in bread dough.

[0034] The content of β-amylase in the modifying agent according to the present technology can be freely set as long as it does not impair the effects of the present technology. The content of β-amylase can be set to, for example, 0.00048 mU or more per 1 g of bread dough, and from the viewpoint of further enhancing the bread modifying effect, the content can be set to preferably 0.0024 mU or more, 0.003 mU or more, 0.004 mU or more, more preferably 0.0048 mU or more, 0.005 mU or more, 0.01 mU or more, 0.05 mU or more, 0.1 mU or more, 1 mU or more, 5 mU or more, 10 mU or more, 20 mU or more, 30 mU or more, 40 mU or more, even more preferably 48 mU or more, 50 mU or more, 60 mU or more, 70 mU or more, 80 mU or more, and even more preferably 87 mU or more.

[0035] The upper limit of the β-amylase content is not particularly limited as long as it does not impair the effects of the present technology, and can be set to, for example, 98 U or less, 80 U or less, 70 U or less, 60 U or less, 50 U or less, 40 U or less, 30 U or less, 20 U or less, 10 U or less, 5 U or less, 1 U or less, 0.5 U or less, 0.2 U or less, 0.15 U or less, or 0.1 U or less per 1 g of bread dough.

[0036] In the present technology, the activity of β-amylase is a value measured by the measurement method described in the Examples below, and the enzymatic activity of β-amylase is defined as the amount of enzyme that, using potato starch as a substrate, increases the reducing power equivalent to 1 mg of glucose per minute, defined as 1 unit (1 U).

[0037] (3) Lipase The lipase that can be used in the present technology is an enzyme that has the activity of hydrolyzing triglycerides to produce diglycerides, monoglycerides, and fatty acids. The lipase that can be used in the present technology may also be an enzyme that has other functions as long as it has the activity of hydrolyzing triglycerides to produce diglycerides, monoglycerides, and fatty acids.

[0038] The origin of the lipase that can be used in the present technology is not particularly limited, and examples thereof include lipases derived from microorganisms of the genus Aspergillus, Candida, Rhizopus, Mucor, and Penicillium. These lipases may be used alone or in combination. Among these lipases, from the viewpoint of further enhancing the bread-improving effect, it is preferable to select a lipase derived from the genus Candida or Penicillium, more preferably a lipase derived from Candia cylindracea or Rhizopus oryzae, and even more preferably a lipase derived from Rhizopus oryzae.

[0039] Here, "lipase derived from Rhizopus oryzae" means a lipase produced by a microorganism classified as Rhizopus oryzae (whether a wild-type strain or a mutant strain), or a lipase obtained by genetic engineering techniques using a lipase gene. Therefore, a recombinant produced by a host microorganism into which a lipase gene obtained from Rhizopus oryzae (or a gene obtained by modifying said gene) has been introduced also falls under the category of "lipase derived from Rhizopus oryzae."

[0040] The lipase used in the present technology can be prepared from a culture solution of a microorganism from which the lipase is derived. Specific preparation methods include recovering the lipase from the culture solution or cells of the microorganism. For example, when a lipase-secreting microorganism is used, the cells can be recovered from the culture solution, if necessary, by filtration, centrifugation, or the like, and the enzyme can then be separated and / or purified. When a lipase-nonsecreting microorganism is used, the cells can be recovered from the culture solution, if necessary, and then disrupted by pressure treatment, ultrasonication, or the like to extract the enzyme, after which the enzyme can be separated and / or purified. The enzyme separation and / or purification method can be any known protein separation and / or purification method, without any particular limitation. Examples include centrifugation, UF concentration, salting out, and various chromatography methods using ion exchange resins. The separated and / or purified enzyme can be powdered by drying methods such as lyophilization and vacuum drying, or by using appropriate excipients and / or drying aids in the drying methods. The isolated and / or purified enzyme can also be liquefied by adding an appropriate additive and sterilizing by filtration.

[0041] In the present technology, commercially available lipases can also be used, and preferred examples of commercially available lipases include lipases derived from microorganisms of the genus Candida and lipases derived from microorganisms of the genus Rhizopus, manufactured by Amano Enzyme Inc.

[0042] In the present technology, the content of lipase in the modifying agent is not particularly limited as long as it does not impair the action and effect of the present technology. The lower limit of the content of lipase in the modifying agent in bread dough is, for example, 5 ppm or more, preferably 15 ppm or more, more preferably 30 ppm or more, and even more preferably 40 ppm or more.

[0043] The upper limit of the lipase content in the modifier can be, for example, 600 ppm or less, preferably 500 ppm or less, more preferably 400 ppm or less, even more preferably 350 ppm or less, and even more preferably 200 ppm or less in bread dough.

[0044] The content of lipase in the modifying agent according to the present technology can be freely set as long as it does not impair the effects of the present technology. The content of lipase can be set to, for example, 0.005 U or more per 1 g of bread dough, and from the viewpoint of further enhancing the bread modifying effect, the content can be set to preferably 0.05 U or more, more preferably 0.5 U or more, even more preferably 1 U or more, 5 U or more, 10 U or more, and even more preferably 15 U or more.

[0045] The upper limit of the lipase content is not particularly limited as long as it does not impair the effects of the present technology, and can be set to, for example, 100,000 U or less, 10,000 U or less, 5,000 U or less, 1,000 U or less, 500 U or less, 200 U or less, 100 U or less, or 80 U or less per 1 g of bread dough.

[0046] In the present technology, the lipase activity is a value measured by the measurement method described in the Examples below.

[0047] (4) Vitamin C Vitamin C, also known as ascorbic acid, usually refers to the L-isomer of ascorbic acid. In the present technology, ascorbic acid or a salt of ascorbic acid can be used as vitamin C. The salt of ascorbic acid is a pharmaceutically acceptable salt, and examples thereof include salts with organic bases (e.g., salts with tertiary amines such as trimethylamine salt, triethylamine salt, monoethanolamine salt, triethanolamine salt, and pyridine salt, basic ammonium salts such as arginine, etc.), salts with inorganic bases (e.g., ammonium salt, alkali metal salts such as sodium salt and potassium salt, alkaline earth metal salts such as calcium salt and magnesium salt, aluminum salt, etc.). Particularly preferred salts of ascorbic acid are sodium salts and potassium salts. Specific examples include sodium ascorbate, sodium ascorbic acid monophosphate, sodium ascorbic acid diphosphate, sodium ascorbic acid triphosphate, and sodium ascorbic acid-2-sulfate.

[0048] In the present technology, the content of vitamin C in the modifier is not particularly limited as long as it does not impair the action and effect of the present technology. The lower limit of the content of vitamin C in the modifier in bread dough can be, for example, 0.3 ppm or more, 1 ppm or more, 10 ppm or more, preferably 15 ppm or more, and more preferably 30 ppm or more.

[0049] The upper limit of the vitamin C content in the modifier can be, for example, 3000 ppm or less, 1000 ppm or less, 300 ppm or less, preferably 200 ppm or less, and more preferably 100 ppm or less in the bread dough.

[0050] (5) Other Components The modifier according to the present technology can be used in combination with other components as long as the action and effect of the present technology are not impaired. Examples of other components that can be used include excipients, pH adjusters, colorants, flavoring agents, disintegrants, lubricants, stabilizers, enzymes, and other components that are commonly used in formulations. Furthermore, components with known or future functions can also be used in combination as appropriate depending on the purpose.

[0051] 2. Frozen Dough, Bread The frozen dough according to the present technology is frozen dough produced using the above-mentioned modifier. Also, the bread according to the present technology is bread produced using the frozen dough produced using the above-mentioned modifier.

[0052] The bread according to the present technology is characterized by high quality despite being produced through a freezing process. Specifically, the volume of the bread according to the present technology is reduced by no more than 20% compared to bread produced without a freezing process, and the volume is preferably equal to or greater than (100%) that of bread produced without a freezing process, more preferably 102% or greater, even more preferably 103% or greater, and even more preferably 110% or greater.

[0053] The upper limit of the hardness of the bread according to the present technology is equal to or less than 100%, preferably 98% or less, and more preferably 95% or less, of bread produced without a freezing process. The lower limit of the hardness of the bread according to the present technology is, for example, 50% or more, preferably 55% or more, more preferably 60% or more, even more preferably 65% ​​or more, and still more preferably 70% or more, of bread produced without a freezing process.

[0054] As described above, the present technology can be suitably used for bread produced without yeast. That is, the frozen dough according to the present technology is preferably a frozen dough without yeast, and the bread according to the present technology is preferably a bread without yeast.

[0055] The present technology can be suitably used for various types of bread, such as breads (leavened bread, unleavened bread, yeast bread, unleavened bread (soda bread, etc.)), toast bread, sweet buns, steamed buns, soft rolls, bagels, donuts, Danish pastries, hamburger buns, pizza, pita bread, ciabatta, baguettes, soft French bread, rolls, pies, pastries, laminated bakery products (croissants, etc.), and cakes.

[0056] 3. Method for Producing Frozen Dough and Method for Producing Bread The method for producing frozen dough and the method for producing bread according to the present technology are methods that at least include a dough preparation step and / or a freezing step. Furthermore, the method for producing bread according to the present technology can also include general bread production steps, such as a thawing step, a fermentation step, and a heating step, before, after, or simultaneously with each step, depending on the type of bread, as long as the effects of the present technology are not impaired. Each step will be described in detail below in chronological order.

[0057] (1) Dough Preparation Step The dough preparation step is a step of preparing dough using one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C. Specifically, it is a step of adding one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C to bread dough ingredients and kneading them to prepare dough. The specific kneading method in the dough preparation step is not particularly limited as long as it does not impair the effects of the present invention, and any kneading method typically used in bread manufacturing methods can be freely selected and used. For example, there are methods such as mixing the dough ingredients using a cooking utensil such as a rubber spatula and then kneading by hand, and methods such as kneading using a machine capable of kneading.

[0058] The dough ingredients used in the dough preparation process can be freely combined with ingredients commonly used in bread dough, as long as they do not impair the effects of the present technology. For example, wheat flour such as soft flour, medium-strength flour, semi-strong flour, and strong flour; wheat flour derived from durum wheat, rice flour, rye flour, barley flour, oat flour, buckwheat flour, barnyard millet flour, foxtail millet flour, corn flour, and starches extracted from various grains; yeast such as dry yeast, fresh yeast, and natural yeast; additives for activating yeast such as yeast food; various seasonings such as salt, mayonnaise, sauce, soy sauce, and amino acids; various ingredients based on milk, such as skim milk powder, whey powder, and butter powder; oils and fats; eggs (including whole eggs, egg yolks, egg whites, and powdered eggs); and various additives such as flavorings, emulsifiers, bread-making improvers, thickeners, stabilizers, and bacteriostatic agents. Thus, while the present technology can freely combine ingredients commonly used in bread dough, it is preferable not to use yeast.

[0059] In the dough preparation process, it is possible to mix and knead all of the ingredients used in the bread dough at the same time, but depending on the types of ingredients to be included in the bread dough, the ingredients can be mixed in any way that suits the ingredients used and the purpose, such as mixing some of the ingredients first and then mixing the remaining ingredients, or mixing several types of ingredients separately and then kneading the mixed ingredients together.

[0060] The amount of one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C added in the dough preparation step can be freely set as long as it does not impair the effects of the present technology. The specific amount added is the same as the content of the modifier described above, so a detailed explanation will be omitted here.

[0061] The specific method of adding each component is not particularly limited, and as long as each component can be added to the ingredients used in the bread dough, it can be added by any method and at any timing. Also, each component can be added in two or more portions.

[0062] When adding one or more enzymes selected from 4-α-glucanotransferase, β-amylase, and lipase, it is preferable to perform an enzyme action step in which the enzyme acts on the ingredients used in the bread dough simultaneously with, before, or after any step in the bread production. The various conditions for the enzyme action step can be freely set as long as they do not impair the effects of the present technology. For example, the pH, temperature, action time, etc. can be set depending on the physicochemical properties of the enzyme used, such as the optimal pH, stable pH range, optimal temperature, and temperature stability. The optimal reaction conditions can be determined through preliminary experiments. Below are examples of conditions for the action of each enzyme.

[0063] [4-α-Glucanotransferase] When 4-α-glucanotransferase is allowed to act on the ingredients used for bread dough, the pH can be set, for example, to pH 3.0 to 11.0, preferably pH 4.0 to 10.0, more preferably pH 5.0 to 9.0, or pH 5.0 to 8.0. The temperature can be set, for example, to 20°C to 90°C, preferably 30°C to 80°C, more preferably 30°C to 70°C, or 30°C to 50°C. The reaction time can be set, for example, to 5 minutes to 24 hours, 10 minutes to 20 hours, preferably 30 minutes to 5 hours, or more preferably 30 minutes to 3 hours.

[0064] [β-amylase] When β-amylase is allowed to act on the ingredients used in the dough, the pH can be set, for example, to 2.0 to 11.0, preferably 3.0 to 10.0, more preferably 4.0 to 9.0, or 5.0 to 9.0. The temperature can be set, for example, to 10°C to 70°C, preferably 30°C to 65°C, or more preferably 45°C to 65°C. The reaction time can be set, for example, to 5 minutes to 24 hours, 10 minutes to 20 hours, preferably 30 minutes to 5 hours, or more preferably 30 minutes to 3 hours.

[0065] [Lipase] When lipase is allowed to act on the ingredients used in bread dough, the pH can be set, for example, to pH 3.0 to 10.0, preferably pH 4.0 to 9.0, and more preferably pH 5.0 to 8.0. The temperature can be set, for example, to 20°C to 70°C, preferably 25°C to 60°C, and more preferably 30°C to 65°C. The acting time can be set, for example, to 5 minutes to 24 hours, 10 minutes to 20 hours, preferably 30 minutes to 5 hours, and more preferably 30 minutes to 3 hours.

[0066] When one or more enzymes selected from 4-α-glucanotransferase, β-amylase, and lipase are used, an enzyme inactivation step can be carried out after the enzymatic action step. The enzyme inactivation step can be carried out simultaneously with any step in the bread production, or before or after any step. For example, in the heating step described below, heating of the bread dough and enzyme inactivation by heating can be carried out simultaneously.

[0067] (2) Freezing Step The freezing step is a step of freezing the dough prepared using one or more ingredients selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C. The freezing method in the freezing step is not limited as long as it does not impair the effects of the present technology, and any general freezing method can be freely selected and used.

[0068] The freezing conditions in the freezing step are not limited as long as they do not impair the effects of the present technology. For example, the temperature conditions for freezing are preferably −25°C or lower, more preferably −30°C or lower, and quick freezing is preferred. The frozen storage conditions for the frozen bread dough are also not limited as long as they do not impair the effects of the present technology. These can be adjusted as appropriate depending on the type and size of the dough, but for example, the temperature conditions during frozen storage are preferably −8 to −22°C, more preferably −12 to −20°C.

[0069] The dough preparation step and the freezing step do not have to be performed by the same facility. For example, one facility can perform the dough preparation step and distribute the dough produced, while another facility can perform the freezing step to produce frozen dough.

[0070] (3) Thawing Step The thawing step is a step of thawing frozen bread dough containing one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C. The thawing method used in the thawing step is not limited as long as it does not impair the effects of the present technology, and any common thawing method can be freely selected and used. Examples of the thawing method include room temperature thawing (1 to 30°C), normal temperature thawing (15 to 25°C), refrigerated thawing (1 to 10°C), and microwave thawing.

[0071] (4) Fermentation Step The fermentation step is a step of fermenting the bread dough thawed in the thawing step. The fermentation step is not essential in the present technology, and as described above, the present technology can be suitably used for bread that does not use yeast, so it is preferable not to perform the fermentation step.

[0072] When the fermentation step is performed, the fermentation method in the fermentation step is not limited as long as it does not impair the effects of the present technology, and any general fermentation method can be freely selected and used. Note that the fermentation step referred to here is the step corresponding to the fermentation of the dough (primary fermentation (floor time), bench time, secondary fermentation (final fermentation, proofing)). In other words, it is not the fermentation when preparing a starter such as in the liquid starter method.

[0073] The fermentation temperature in the fermentation step can be freely set depending on the type of yeast used and the state of the dough, as long as it does not impair the effects of the present invention. For example, the fermentation temperature in the fermentation step is preferably set to 23 to 40°C, and more preferably set to 26 to 35°C.

[0074] The fermentation time in the fermentation step can also be freely set depending on the type and amount of yeast used and the state of the dough, as long as it does not impair the effects of the present invention. For example, the fermentation time in the fermentation step is preferably set to 30 minutes to 24 hours, and more preferably set to 1 to 16 hours.

[0075] The fermentation process can be carried out in multiple stages, for example, by carrying out each stage in the following order: primary fermentation (floor time), dividing process (described later), bench time, shaping process (described later), and secondary fermentation (final fermentation, proofing).

[0076] (5) Dividing Step The dividing step is a step of dividing the prepared bread dough. In the present technology, the dividing step is not essential and can be carried out as appropriate depending on the type of bread to be produced, etc.

[0077] The dividing step can be carried out at any time after the dough preparation step. For example, after the dough preparation step, the dough can be appropriately rested until it settles, then divided into portions of desired size, and the divided portions can be frozen. Alternatively, the frozen dough can be thawed, divided into portions of desired size, shaped appropriately, and fermented as necessary, followed by the heating step described below.

[0078] (6) Shaping step The shaping step is a step of shaping the prepared bread dough. In the present technology, the shaping step is not essential and can be carried out as appropriate depending on the type of bread to be produced, etc.

[0079] The shaping step can be carried out at any time after the dough preparation step. For example, after the dough preparation step, the dough can be allowed to rest until it settles, then shaped into a desired shape and frozen. Alternatively, the frozen dough can be thawed, shaped into a desired shape, and fermented as necessary, followed by the heating step described below.

[0080] (7) Heating Step The heating step is a step of heating the dough. The heating method in the heating step is not limited as long as it does not impair the effects of the present technology, and any common heating method can be freely selected and used. Examples include baking, deep-frying, steaming, microwave heating, etc.

[0081] The heating temperature in the heating step can be freely set depending on the type and shape of the bread to be produced, the heating method, etc., as long as it does not impair the effects of the present invention. For example, the heating temperature in the heating step is preferably set to 140 to 280°C, and more preferably set to 160 to 240°C.

[0082] The heating time in the heating step can also be freely set depending on the type and shape of the bread to be produced, the heating method, etc., as long as it does not impair the effects of the present invention. For example, the heating time in the heating step is preferably set to 10 minutes to 2 hours, and more preferably set to 15 minutes to 1 hour.

[0083] The present invention will be described in more detail below with reference to examples. Note that the examples described below are representative examples of the present invention and should not be construed as narrowing the scope of the present invention.

[0084] 1. Raw Materials The materials used in the Examples are shown in Table 1 below, and the enzymes used in the Examples are shown in Table 2 below.

[0085]

[0086]

[0087] 2. Enzyme Activity Measurement Method [4-α-Glucanotransferase Activity Measurement Method] 180 mg of maltotetraose (Hayashibara) was weighed and placed in a 20 mL volumetric flask. Approximately 15 mL of 10 mmol / L MES buffer (pH 6.5) was added to dissolve the maltotetraose. Once dissolved, 10 mmol / L MES buffer (pH 6.5) was added to the solution, and the resulting volume was adjusted to 20 mL. This was used as the substrate solution. 2 mL of the substrate solution was placed in a test tube and allowed to stand at 40 ± 0.5°C for 10-15 minutes. 0.5 mL of the sample solution was then added, shaken well, and allowed to stand at 40 ± 0.5°C for exactly 60 minutes. After standing, the tube was placed in a boiling water bath, heated for exactly 5 minutes, and then cooled under running water. The glucose produced was quantified using a Labo Assay Glucose (Fujifilm Wako Pure Chemical Corporation). The Lab Assay Glucose kit consists of a coloring agent containing mutarotase, glucose oxidase, peroxidase, 4-aminoantipyrine, and ascorbic acid oxidase, and a buffer containing phosphate buffer (pH 7.1) and phenol. It can determine glucose concentration by measuring the red pigment produced by the oxidative condensation of phenol and 4-aminoantipyrine. Under these conditions, one unit of enzyme is defined as the amount of enzyme that produces 1 μmol of glucose per minute.

[0088] [β-Amylase] Measurement was performed according to the method described in the Japanese Standards of Food Additives (9th edition). The specific method is as follows. Potato starch was used as a substrate. It was dried at 105°C for 2 hours in advance. 1.0 g of the dried material was weighed out, 20 mL of water was added, and 5 mL of sodium hydroxide TS (2 mol / L) was gradually added with stirring to form a paste. Next, the mixture was heated in a water bath with stirring for 3 minutes, and then 25 mL of water was added. After cooling, the mixture was neutralized with hydrochloric acid TS (2 mol / L) and hydrochloric acid TS (0.1 mol / L). 10 mL of 1 mol / L acetic acid / sodium acetate buffer (pH 5.0) was added, and water was added to make a total of 100 mL to prepare a substrate solution. Ten mL of substrate solution was weighed and heated at 37°C for 10 minutes. 1 mL of sample solution was added and immediately shaken. After heating at the same temperature for 10 or 30 minutes, 4 mL of Fehling's TS solution was added and gently shaken. After heating in a water bath for 15 minutes, the mixture was cooled to below 25°C. 2 mL of 30% potassium iodide solution and 2 mL of sulfuric acid (1 → 6) were added to prepare the test solution. Fehling's TS solution was prepared immediately after use by mixing 1 volume of copper solution with 1 volume of alkaline tartrate solution, prepared by dissolving 34.66 g of fine copper(II) sulfate pentahydrate crystals in water to make 500 mL, and 173 g of sodium potassium (+)-tartrate tetrahydrate and 50 g of sodium hydroxide in water to make 500 mL. A separate comparison solution was prepared using 10 mL of water instead of the substrate solution, following the same procedure as for the test solution. The liberated iodine in the test solution and the control solution was titrated with 0.05 mol / L sodium thiosulfate solution. The endpoint was determined when 1-2 drops of soluble starch test solution were added as the titration approached the end point and the resulting blue color disappeared. The amount of enzyme that increases the reducing power equivalent to 1 mg of glucose per minute was defined as 1 unit (1 U), and this was calculated using the following formula:β-Amylase activity (U / g, U / mL) = amount of glucose (mg) × 1 / 10 × 1 / M Amount of glucose (mg) = (b - a) × 1.6 × f a: Titration value (mL) of enzyme reaction solution b: Titration value (mL) of blank solution 1.6: 1 mL of 0.05 mol / L sodium thiosulfate solution corresponds to 1.6 mg of glucose 1 / 10: Unit conversion coefficient for reaction time (minutes) M: Amount of sample (g or mL) in 1 mL of sample solution f: Factor of 0.05 mol / L sodium thiosulfate solution (for quantitation).

[0089] Lipase activity can be measured using a method based on the lipase activity test method in the 9th edition of the Japanese Standards for Food Additives. First, 45 g of olive oil was mixed with 150 mL of emulsion (18.5 g / L polyvinyl alcohol (fully saponified, saponification degree 98.8 ± 0.2), 1.5 g / L polyvinyl alcohol (partially saponified, saponification degree 88.8 ± 1.0)) and emulsified using a homogenizer to prepare a substrate solution. 1 mL of lipase enzyme solution was added to 5 mL of the prepared substrate solution and 4 mL of 0.1 mol / L phosphate buffer (pH 7.0), and the reaction was carried out at 37°C. After 30 minutes, 10 mL of an ethanol-acetone mixture was added to terminate the enzyme reaction. Next, 10 mL of 0.05 mol / L sodium hydroxide solution and 10 mL of an ethanol-acetone mixture were added, and the mixture was titrated to pH 10 with 0.05 mol / L hydrochloric acid. The amount of enzyme that increases 1 μmol of fatty acid per minute is defined as 1 unit (1 U).

[0090] 3. Experimental Examples <Experimental Example 1> (1) Production of frozen bread dough The ingredients other than the liquid shortening shown in Table 1 were mixed in a bowl, and then the liquid shortening and the ingredients shown in Table 3 below were added and kneaded to prepare dough. The prepared dough was divided into 30 g portions, allowed to rest at room temperature for 1 hour, and then frozen at -20°C for 7 days.

[0091] (2) Bread Production The frozen dough prepared above was thawed at room temperature for 1 hour. The thawed dough was placed in a preheated oven with an upper temperature of 170°C and a lower temperature of 165°C and baked for 35 minutes to produce bread. A control example was prepared by preparing dough without the freezing step and baking it under the same conditions.

[0092] (3) Evaluation The produced bread was left to rest at room temperature for 3 hours, and then the volume and hardness were measured by the following methods.

[0093] [Volume] The volume of the bread was measured according to the method described in the Chinese National Standard GB / T 35869-2018, "Evaluation of Baking Quality for Crop Oil, Dian, Yan, and Wheat Flour, and Rapid Baking Method," replacing rapeseed with water. Specifically, the bread wrapped in plastic wrap was placed in an empty 500 mL measuring cylinder, and then the bread was secured with a thin rod to prevent it from floating. Water was then poured into the measuring cylinder up to the 300 mL line. The wrapped bread was then removed, and the remaining volume of water was designated V1 (mL). The volume of the bread, V2 (mL), was calculated by subtracting V1 from 300 mL.

[0094] [Hardness] The hardness (g) of the bread was measured using a rheometer (Stable Micro Systems "TA.XTplus Texture Analyser") according to the method described in the instruction manual. The bread was rested at room temperature for 3 hours and placed on the platform of the rheometer (equipped with a P / 25 probe). The initial pressing force was set to 5 g (equivalent to 0.049 N), and the pressing and returning speeds of the probe were set to 1.0 mm / s. The bread was pressed with the probe until it deformed 50%, and the hardness (g) of the bread was measured.

[0095] (4) Results The results are shown in Table 3 below.

[0096]

[0097] (5) Discussion As shown in Table 3, Comparative Examples 1 and 2, which did not use one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C, were harder than Control Example 1, which did not undergo a freezing process. In contrast, Examples 1 to 5, which used one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C, were softer than Control Example 1, which did not undergo a freezing process. Furthermore, the volume increase rates of Examples 1 to 5, which used one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C, were improved compared to the volume increase rates of Comparative Examples 1 and 2, which did not use one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C, relative to Control Example 1, which did not undergo a freezing process. Furthermore, a sensory evaluation of the texture confirmed that Examples 1 to 5 had a better texture than Comparative Examples 1 and 2.

[0098] Experimental Example 2 (1) Production of frozen bread dough The ingredients other than the liquid shortening shown in Table 1 were mixed in a bowl, and then the liquid shortening and the ingredients shown in Table 4 below were added and kneaded to prepare dough. The prepared dough was divided into 30 g portions, allowed to rest at room temperature for 1 hour, and then frozen at -20°C for 35 days.

[0099] (2) Production of Bread Bread was produced in the same manner as in Experimental Example 1.

[0100] (3) Evaluation The volume and hardness were measured in the same manner as in Experimental Example 1.

[0101] (4) Results The results are shown in Table 4 below.

[0102]

[0103] (5) Discussion As shown in Table 4, Comparative Example 3, which did not use one or more components selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C, was harder than Control Example 2, which did not undergo a freezing step, whereas Examples 6 to 8, which used one or more components selected from 4-α-glucanotransferase, lipase, and vitamin C, were softer than Control Example 2, which did not undergo a freezing step. Furthermore, the volume of Example 6, which used vitamin C, was smaller than that of Control Example 2, which did not undergo a freezing step, but Examples 7 and 8, which used two or more components selected from 4-α-glucanotransferase, lipase, and vitamin C, had a larger volume than Control Example 2, which did not undergo a freezing step. Furthermore, when comparing the Examples, Example 6, which used only vitamin C, showed a higher reduction in hardness than Control Example 2, which was not subjected to a freezing process, and tended to be too soft, whereas Examples 7 and 8, which used two or more components selected from 4-α-glucanotransferase, lipase, and vitamin C, were not too soft. Furthermore, as a result of a sensory evaluation of the texture, it was confirmed that Examples 7 and 8 had a good texture similar to that of Control Example 2.

[0104] Experimental Example 3 A sensory evaluation was carried out based on the following criteria for the texture and color of Examples 7 and 8, Comparative Example 3, and Control Example 2 of Experimental Example 2. The average scores of four expert panelists were used as the score.

[0105] [Texture] 16-20 points: The outer skin is crisp and fits well to the teeth, the inside is chewy and moderately soft, and the texture is fine. 10-15 points: The outer skin is a little hard, a little sticky to the teeth, and the texture is relatively fine. 0-9 points: The outer skin is hard, sticky to the teeth, and the texture is coarse.

[0106] [Color] 16-20 points: Golden and uniform color tone 10-15 points: The color tone is basically uniform, with no overly burnt or overly white areas 0-9 points: The color tone is uneven, with overly burnt or overly white areas

[0107] The results are shown in Table 5 below.

[0108]

[0109] As shown in Table 5, Examples 7 and 8 had better results in terms of texture and color than Control Example 2 and Comparative Example 3.

Claims

1. A bread improver for use in making frozen dough, which contains one or more ingredients selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C.

2. Frozen bread dough using the bread improver according to claim 1.

3. Bread made using the frozen bread dough according to claim 2.

4. A method for producing bread using frozen dough, comprising a dough preparation step of preparing dough using one or more ingredients selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C.

5. A method for producing bread using frozen dough, comprising a freezing step of freezing dough prepared using one or more ingredients selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C.

6. A method for improving bread produced using frozen dough, comprising a dough preparation step of preparing dough using one or more ingredients selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C.

7. A method for improving bread produced using frozen bread dough, comprising a freezing step of freezing dough prepared using one or more ingredients selected from 4-α-glucanotransferase, β-amylase, lipase, and vitamin C.

Images