Method for improving quality of bread with high-proportion added potato powder based on multi-stage enzymolysis

Abstract

The invention discloses a method for improving the quality of bread with high-proportion added potato powder based on multi-stage enzymolysis, and belongs to the technical field of food processing. Comprising the following steps: (1) carrying out enzymolysis treatment on potato raw whole powder by adopting a compound enzyme to prepare enzymolysis dough; (2) mixing the enzymolysis dough with wheat flour and potato starch, and kneading dough to prepare dough added with high-proportion potato whole flour; and (3) on the basis of the dough prepared in the step (2), adding an emulsifier, sugar, yeast and milk powder, continuously stirring to preliminarily form dough, then adding butter and edible salt, continuously stirring until gluten protein is fully expanded, cutting, shaping, putting into a fermentation box for fermentation, putting the fermented dough into an oven, baking, demolding and cooling to obtain the potato bread. The method effectively increases the specific volume of the potato bread and improves the texture of the potato bread, and has the advantages of simple process operation and low cost.

Description

Technical Field

[0001] The invention relates to a method for improving the quality of bread with high-proportion addition of potato flour based on multi-stage enzymatic hydrolysis, and belongs to the technical field of dough processing. Background Art

[0002] Potatoes (scientific name Solanum tuberosum L.), commonly known as potatoes, sweet potatoes, yam eggs, etc., have high yields and strong resistance to adversity, and are the world's fourth largest staple food. Potatoes are nutritionally complete and rich in dietary fiber, multiple vitamins, minerals and other trace bioactive substances that are beneficial to the human body. In view of the huge yield and comprehensive nutrition of potatoes, adding potato flour as the main raw material to bread can make up for the lack of amino acids, dietary fiber, vitamins and other nutrients in refined wheat flour. Without changing people's eating habits, it can meet the nutritional balance of residents' diets. It not only complies with the national strategy of making potatoes a staple food, but also meets the demand for nutritional fortification of staple bread.

[0003] However, since potato flour does not contain gluten protein, its large addition causes the quality of bread to decline. As the proportion of potato flour added increases, the bread has problems such as decreased specific volume and increased hardness. Therefore, the development of bread with a high proportion of potato flour, which transforms whole flour from an auxiliary ingredient to a main ingredient, is considered by the industry to be the pain point and difficulty of potato-fermented products, especially the development of compound bread with a potato addition of up to 50%, which is a problem that needs to be solved urgently in the industry.

[0004] Previously, some researchers tried to improve the quality of potato bread by adding gluten to potato composite dough, but the improvement effect was limited. As the proportion of potato flour added to the composite dough increased significantly, the integrity of the gluten network structure in the dough was destroyed, which in turn affected the quality of the bread. Exogenous additives can strengthen the gluten network structure to a certain extent, but the existing methods do not change the effect of the cellulose components present in large quantities in potato flour on the formation of the gluten protein network structure. Therefore, relying solely on exogenous additives to improve the quality of high-proportion potato composite bread is relatively limited. Summary of the invention

[0005] In view of the shortcomings and defects of the prior art, the present invention provides a method for improving the quality of bread with high proportion of potato flour based on multi-stage enzymatic hydrolysis, which is not only low-cost and simple in process, but also has the advantages of large specific volume, soft texture, uniform structure, etc. The present invention uses enzymatic hydrolysis to adjust the fiber components in potatoes and strengthen the formation and stability of gluten protein network structure by supplementing potato starch, optimizes dough starch distribution by starch branching enzyme, and supplements potato starch to strengthen dough structure, thereby improving the specific volume of potato bread and improving the texture characteristics of potato bread.

[0006] The first object of the present invention is to provide a method for preparing dough with a high proportion of potato whole flour, comprising the following steps:

[0007] (1) using a composite enzyme to enzymatically hydrolyze whole potato flour to obtain enzymatically hydrolyzed dough;

[0008] (2) The enzymatically hydrolyzed dough is mixed with wheat flour and potato starch, and kneaded to obtain a dough with a high proportion of potato whole flour added.

[0009] In one embodiment of the present invention, in step (1), the complex enzyme consists of cellulase, pectinase and starch branching enzyme;

[0010] The added amounts of cellulase, pectinase and starch branching enzyme relative to the dry basis of raw potato whole flour are 0.10-0.35 U / g, 0.10-0.35 U / g and 0.10-0.40 U / g respectively.

[0011] In one embodiment of the present invention, the amount of cellulase added relative to the dry basis of raw potato flour is 0.15-0.20 U / g.

[0012] In one embodiment of the present invention, the added amount of pectinase relative to the dry basis of raw potato flour is 0.15-0.20 U / g.

[0013] In one embodiment of the present invention, the amount of starch branching enzyme added relative to the dry basis of raw potato whole flour is 0.20-0.25 U / g.

[0014] In one embodiment of the present invention, the added amounts of cellulase, pectinase and starch branching enzyme are 0.20 U / g, 0.20 U / g and 0.25 U / g, respectively, based on the dry basis of raw potato flour.

[0015] In one embodiment of the present invention, in step (1), the cellulase and pectinase are respectively derived from Bacillus licheniformis.

[0016] In one embodiment of the present invention, in step (1), the starch branching enzyme is derived from Geobacillus thermoglucosidans, has an EC number of 2.4.1.18., and an enzyme activity of 1200-1600 U / mL.

[0017] In one embodiment of the present invention, in step (1), the temperature of enzymolysis is 45-55°C, and the time of enzymolysis is 55-65 min.

[0018] In one embodiment of the present invention, in step (1), the pH value of the enzymatic hydrolysis is 5.0-6.0.

[0019] In one embodiment of the present invention, in step (1), the specific method is: dissolving the complex enzyme in deionized water, then adding it to the whole potato flour, mixing into a mass, and placing it in a proofing box for heat preservation and enzymolysis. The enzymolysis causes the fiber components to be peeled off from the surface of the potato starch particles.

[0020] In one embodiment of the present invention, in step (1), the enzymatic hydrolysis temperature is 45-55°C, and the enzymatic hydrolysis time is 55-65 min.

[0021] In one embodiment of the present invention, in step (1), the enzymatically hydrolyzed dough does not need to be dried and is directly placed in a dough mixer together with wheat flour.

[0022] In one embodiment of the present invention, the amount of wheat flour used is calculated based on the mass of raw potato flour before enzymatic hydrolysis.

[0023] In one embodiment of the present invention, in step (2), the amount of potato starch used is 5-10% of the total mass of raw potato flour and wheat flour. Potato starch can further support the gluten network structure.

[0024] The second object of the present invention is to provide a dough prepared by the above preparation method and containing a high proportion of potato whole flour.

[0025] The third object of the present invention is to provide a use of the dough for preparing potato bread.

[0026] A method for making potato bread from the dough comprises the following steps:

[0027] An emulsifier is added to the dough with a high proportion of potato whole flour, and the potato bread with a high proportion of potato whole flour is prepared after kneading, proofing and baking.

[0028] In one embodiment of the present invention, the emulsifier is sodium stearoyl lactylate, and the amount used is 1-1.5% of the total mass of raw potato flour and wheat flour.

[0029] In one embodiment of the present invention, one or more of sugar, yeast, milk powder, butter and edible salt are further added to the dough.

[0030] In one embodiment of the present invention, the raw materials for preparing potato bread include: 30-50 parts of raw potato whole flour, 50-70 parts of wheat flour, 1-1.5 parts of emulsifier, 5-10 parts of potato starch, 1-3 parts of yeast, 5-10 parts of sugar, 1-3 parts of edible salt, 2-4 parts of milk powder, 4-6 parts of butter, and 132-142 parts of water.

[0031] In one embodiment of the present invention, a small dough mixer is used for dough kneading.

[0032] In one embodiment of the present invention, the method for making potato bread specifically comprises the following steps:

[0033] Cellulase, pectinase and starch branching enzyme are mixed with water, added to raw potato flour, stirred evenly in a dough mixer and placed in a proofing box for enzymatic hydrolysis to obtain enzymatic dough. Subsequently, it is continuously stirred with wheat flour, potato starch, emulsifier, sugar, yeast and milk powder to initially form a dough, and then butter and edible salt are added and stirred until the gluten protein is fully expanded. After being divided and shaped, it is placed in a proofing box for proofing, and the proofed dough is placed in an oven for baking, demolding and cooling to obtain potato bread.

[0034] In one embodiment of the present invention, the enzymatically hydrolyzed potato whole flour and other raw materials except butter and edible salt are first mixed at a low speed for 4 minutes and then stirred at a medium speed and a high speed for 3 minutes respectively.

[0035] In one embodiment of the present invention, after adding butter and edible salt, stir at a low speed for 1 minute until the butter and edible salt are fully absorbed, and then stir at a medium speed and a high speed for 2 minutes respectively to fully expand the gluten.

[0036] In one embodiment of the present invention, the proofing conditions are: temperature of 35-38° C., relative humidity of 85-90%, and time of 90 min.

[0037] In one embodiment of the present invention, the baking temperature is 170-210° C. and the baking time is 20-25 min.

[0038] Beneficial effects of the present invention:

[0039] (1) The present invention uses a combination of multiple enzymes to adjust the distribution of fiber components in potatoes, and optimizes the starch structure by adding branching enzymes and supplementing potato starch to strengthen the formation and stability of the gluten protein network structure, thereby increasing the specific volume of potato composite dough and achieving the purpose of improving the texture characteristics of potato bread.

[0040] (2) The present invention uses cellulase and pectinase to moderately enzymatically hydrolyze the cellulose and pectin components in raw potato flour, thereby reducing the destructive effect of the fiber components rich in potato flour on the gluten network during the dough kneading process; starch branching enzyme is used to further optimize the starch structure in the dough; in addition, a certain amount of potato starch is added to the dough. The potato starch with larger particles can support gluten protein fibrils and promote the formation and expansion of the gluten network structure, thereby improving the processing characteristics of the dough.

[0041] (3) At present, the quality improvement of potato bread mainly involves adding enzyme preparations such as gluten to promote the cross-linking of gluten protein network structure, which has very limited effect on the improvement of bread volume and texture. The present invention uses cellulase and pectinase to hydrolyze the fiber components in raw potato flour, which can strengthen the gluten protein network structure on the one hand, and on the other hand, the hydrolyzed fiber components can produce more fermentable sugars and yeast metabolites, thereby optimizing the dough structure.

[0042] (4) Based on adjusting the fiber components in raw potato flour, the present invention uses starch branching enzyme to further optimize the starch structure in the dough and supplement a certain amount of potato starch. The present invention is not only simple to operate and low in cost, but also can effectively improve the quality of bread and give potato bread a larger specific volume and a softer tissue structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 The figure shows the effects of Example 3 of the present invention and the control example on the dough microstructure. DETAILED DESCRIPTION

[0044] In order to make the purpose, features and technical solutions of the present invention more obvious and easy to understand, the present invention is described in more detail below by combining the accompanying drawings and specific embodiments. However, the protection scope of the present invention is not limited thereto. The experimental methods used in the following embodiments are conventional methods unless otherwise specified; the reagents, materials, etc. used in the following embodiments are all commercially available unless otherwise specified.

[0045] The cellulase and pectinase mentioned in the following examples are derived from Bacillus licheniformis, and the starch branching enzyme is derived from Geobacillus thermoglucosidans.

[0046] Test method:

[0047] (1) Determination of specific volume of bread: The specific volume of bread was measured using the AACC 10-05.0 volume displacement method, i.e., the ratio of the volume to the mass of the bread (mL / g).

[0048] (2) Determination of bread texture: The prepared bread was cooled at room temperature for 2 hours and then cut into 1 cm thick slices. The whole texture of the bread was measured using an XTplus texture analyzer. The test procedure was as follows: a P / 25 probe was used, and the speeds before, during and after the test were 1 mm / s, 0.5 mm / s and 1 mm / s respectively, and the compression ratio was 50%. The test was repeated 6 times and the average value was taken.

[0049] (3) Determination of dough fermentation rheological properties: The rheological properties of dough were measured using an F3 fermentation rheometer to simulate the dough fermentation process. 250.0 g of dough was weighed and placed in a preheated fermentation chamber. A 2 kg weight was placed on the dough. The measurement environment temperature was set to 38 °C and the fermentation time was 180 min.

[0050] (4) Observation of dough microstructure: The bread crumbs were frozen and sliced, and the slices were stained with fluorescein isothiocyanate (FITC) and rhodamine B. The dough microstructure was observed using a confocal microscope.

[0051] Example 1

[0052] A method for preparing potato bread, comprising the following steps:

[0053] In terms of weight, 1 part is equal to 1 kg. The raw powder ratio is as follows: 30 parts of whole potato flour, 70 parts of wheat flour, 5 parts of potato starch, 3 parts of yeast, 10 parts of sugar, 4 parts of milk powder, 3 parts of table salt, 4 parts of butter, 1 part of emulsifier, and 132 parts of water.

[0054] 0.2U / g cellulase, 0.2U / g pectinase and 0.3U / g starch branching enzyme are dissolved in deionized water (based on the dry basis of raw whole potato flour), and the whole potato flour is added and mixed, and then placed in a proofing box at 55°C for enzymatic hydrolysis for 60 minutes. Subsequently, the enzymatically hydrolyzed whole potato flour is mixed with wheat flour, potato starch, emulsifier, sugar, yeast and milk powder at a low speed for 4 minutes, and then stirred at a medium speed and a high speed for 3 minutes respectively to initially form a dough, and then butter and edible salt are added, and the dough is stirred continuously until the gluten protein is fully expanded. After being divided and shaped, the dough is placed in a proofing box at a temperature of 38°C and a relative humidity of 90% for 90 minutes, and the proofed dough is placed in an oven, and baked at 170°C for the upper fire and 210°C for the lower fire for 23 minutes, demolded, cooled, and potato bread is obtained.

[0055] Example 2

[0056] A method for preparing potato bread, comprising the following steps:

[0057] In terms of weight, 1 part is equal to 1 kg. The raw powder ratio is as follows: 40 parts of whole potato flour, 60 parts of wheat flour, 3 parts of yeast, 10 parts of sugar, 4 parts of milk powder, 3 parts of table salt, 4 parts of butter, 5 parts of potato starch, 1 part of emulsifier, and 139 parts of water.

[0058] 0.2U / g cellulase, 0.2U / g pectinase and 0.3U / g starch branching enzyme are dissolved in deionized water (based on the dry basis of raw whole potato flour), and the whole potato flour is added and mixed, and then placed in a proofing box at 55°C for enzymatic hydrolysis for 60 minutes. Subsequently, the enzymatically hydrolyzed whole potato flour is mixed with wheat flour, potato starch, emulsifier, sugar, yeast and milk powder at a low speed for 4 minutes, and then stirred at a medium speed and a high speed for 3 minutes respectively to initially form a dough, and then butter and edible salt are added, and the dough is stirred continuously until the gluten protein is fully expanded. After being divided and shaped, the dough is placed in a proofing box at a temperature of 38°C and a relative humidity of 90% for 90 minutes, and the proofed dough is placed in an oven, and baked at 170°C for the upper fire and 210°C for the lower fire for 23 minutes, demolded, cooled, and potato bread is obtained.

[0059] Example 3

[0060] A method for preparing potato bread, comprising the following steps:

[0061] In terms of weight, 1 part is equal to 1 kg. The raw powder ratio is as follows: 50 parts of whole potato flour, 50 parts of wheat flour, 3 parts of yeast, 10 parts of sugar, 4 parts of milk powder, 3 parts of table salt, 4 parts of butter, 5 parts of potato starch, 1 part of emulsifier, and 142 parts of water.

[0062] 0.2U / g cellulase, 0.2U / g pectinase and 0.3U / g starch branching enzyme are dissolved in deionized water (based on the dry basis of raw whole potato flour), and the whole potato flour is added and mixed, and then placed in a proofing box at 55°C for enzymatic hydrolysis for 60 minutes. Subsequently, the enzymatically hydrolyzed whole potato flour is mixed with wheat flour, potato starch, emulsifier, sugar, yeast and milk powder at a low speed for 4 minutes, and then stirred at a medium speed and a high speed for 3 minutes respectively to initially form a dough, and then butter and edible salt are added, and the dough is stirred continuously until the gluten protein is fully expanded. After being divided and shaped, the dough is placed in a proofing box at a temperature of 38°C and a relative humidity of 90% for 90 minutes, and the proofed dough is placed in an oven, and baked at 170°C for 23 minutes and 210°C for 23 minutes, and then demolded and cooled to obtain potato bread.

[0063] Comparative Example 1

[0064] The method of Example 3 was used with reference to the method of Example 3, except that no enzyme preparation and potato starch were added, and the other conditions were the same as those of Example 3; the potato bread produced by this method was recorded as Control Example 1.

[0065] Comparative Example 2

[0066] A method for preparing potato bread, comprising the following steps:

[0067] In terms of weight, 1 part is equal to 1 kg. The raw powder ratio is as follows: 50 parts of whole potato flour, 50 parts of wheat flour, 3 parts of yeast, 10 parts of sugar, 4 parts of milk powder, 3 parts of table salt, 4 parts of butter, 5 parts of potato starch, 1 part of emulsifier, and 142 parts of water.

[0068] Dissolve cellulase in deionized water at the addition amount of 0U / g, 0.1U / g, 0.2U / g, 0.3U / g, 0.4U / g and 0.5U / g, add potato flour and mix well, then place in a proofing box at 55°C for enzymolysis for 60 minutes. Then, mix the enzymolyzed potato flour with wheat flour, potato starch, emulsifier, sugar, yeast and milk powder at low speed for 4 minutes, then stir at medium speed and high speed for 3 minutes respectively to form a dough, add butter and edible salt, continue stirring until gluten protein is fully expanded, divide and shape, place in a proofing box at 38°C and relative humidity of 90% for 90 minutes, place the proofed dough in an oven, bake at 170°C on the upper fire and 210°C on the lower fire for 23 minutes, demould and cool, and obtain potato bread.

[0069] Table 1 Specific volume and texture characteristics of potato bread after adding cellulase

[0070] Cellulase addition amount (U / g) specific volume Hardness(g) elasticity(%) Adhesion / g Chewability / g 0 1.89 351.12 87.13 437.12 300.26 0.1 1.91 330.26 88.76 410.56 286.10 0.2 2.17 319.33 92.67 367.52 258.31 0.3 2.10 324.53 91.44 382.78 266.26 0.4 1.98 341.37 87.78 419.35 286.10 0.5 1.94 355.21 84.87 439.90 311.18

[0071] Comparative Example 3

[0072] A method for preparing potato bread, comprising the following steps:

[0073] In terms of weight, 1 part is equal to 1 kg. The raw powder ratio is as follows: 50 parts of whole potato flour, 50 parts of wheat flour, 3 parts of yeast, 10 parts of sugar, 4 parts of milk powder, 3 parts of table salt, 4 parts of butter, 5 parts of potato starch, 1 part of emulsifier, and 142 parts of water.

[0074] Pectinase was dissolved in deionized water at the addition amount of 0U / g, 0.1U / g, 0.2U / g, 0.3U / g and 0.5U / g, and potato flour was added and mixed, and then placed in a proofing box at 55°C for enzymatic hydrolysis for 60 minutes. Subsequently, the enzymatically hydrolyzed potato flour was mixed with wheat flour, potato starch, emulsifier, sugar, yeast and milk powder, and mixed at a low speed for 4 minutes, and then stirred at a medium speed and a high speed for 3 minutes respectively to initially form a dough, and then butter and edible salt were added, and the dough was stirred until the gluten protein was fully expanded. After being divided and shaped, the dough was placed in a proofing box at a temperature of 38°C and a relative humidity of 90% for 90 minutes, and the proofed dough was placed in an oven, and baked at 170°C on the upper fire and 210°C on the lower fire for 23 minutes, and then demolded and cooled to obtain potato bread.

[0075] Table 2 Specific volume and texture characteristics of potato bread after adding pectinase

[0076] Pectinase addition amount (U / g) specific volume Hardness(g) elasticity(%) Adhesion / g Chewability / g 0 1.89 351.12 87.13 437.12 300.26 0.1 1.80 355.59 87.15 434.87 299.13 0.2 1.98 303.56 94.70 407.87 278.37 0.3 1.83 353.48 91.24 423.91 287.92 0.4 1.82 343.76 86.77 433.56 265.21 0.5 1.74 359.12 83.59 437.86 307.46

[0077] Comparative Example 4

[0078] A method for preparing potato bread, comprising the following steps:

[0079] In terms of weight, 1 part is equal to 1 kg. The raw powder ratio is as follows: 50 parts of whole potato flour, 50 parts of wheat flour, 3 parts of yeast, 10 parts of sugar, 4 parts of milk powder, 3 parts of table salt, 4 parts of butter, 5 parts of potato starch, 1 part of emulsifier, and 142 parts of water.

[0080] The starch branching enzyme is dissolved in deionized water at the addition amount of 0U / g, 0.1U / g, 0.2U / g, 0.3U / g and 0.5U / g, and the whole potato flour is added and mixed, and then placed in a proofing box at 55°C for enzymatic hydrolysis for 60 minutes. Subsequently, the enzymatically hydrolyzed whole potato flour is mixed with wheat flour, potato starch, emulsifier, sugar, yeast and milk powder, and mixed at a low speed for 4 minutes, and then stirred at a medium speed and a high speed for 3 minutes respectively to initially form a dough, and then butter and salt are added, and the dough is stirred continuously until the gluten protein is fully expanded. After being divided and shaped, the dough is placed in a proofing box at a temperature of 38°C and a relative humidity of 90% for 90 minutes, and the proofed dough is placed in an oven, and baked at 170°C on the upper fire and 210°C on the lower fire for 23 minutes, demolded, cooled, and potato bread is obtained.

[0081] Table 3 Specific volume and texture characteristics of potato bread after addition of starch branching enzyme

[0082] Starch branching enzyme addition amount (U / g) specific volume Hardness(g) elasticity(%) Adhesion / g Chewability / g 0 1.89 351.12 87.13 437.12 300.26 0.1 1.86 313.76 92.24 389.88 314.24 0.2 2.13 303.56 94.70 407.87 278.37 0.3 2.35 245.65 94.23 423.91 287.92 0.4 2.27 248.93 93.29 411.76 256.11 0.5 2.32 244.76 92.56 412.87 283.17

[0083] It can be seen from Control Examples 2, 3 and 4 that in the preparation of high-ratio potato bread, the optimal addition ratios of cellulase, pectinase and starch branching enzyme are 0.2U / g, 0.2U / g and 0.3U / g. In the embodiment, we selected the addition amounts of cellulase, pectinase and starch branching enzyme to be 0.2U / g, 0.2U / g and 0.3U / g.

[0084] Comparative Example 5

[0085] The method of Example 3 was referred to, except that no enzyme preparation was added, only potato starch was added, and the rest was the same as Example 3; the potato bread produced was recorded as Control Example 5.

[0086] The specific volume and texture characteristics of the potato bread products prepared in Examples 1-3 and Comparative Examples 1-5 are shown in Table 4.

[0087] Table 4 Specific volume and texture characteristics of potato bread

[0088] sample specific volume Hardness(g) elasticity(%) Adhesion / g Chewability / g Example 1 3.91 181.52 99.27 113.47 224.64 Example 2 3.87 226.87 96.98 216.89 265.07 Example 3 3.34 292.41 96.81 265.47 282.31 Comparative Example 1 1.89 738.26 88.54 509.75 439.71 Comparative Example 2 2.17 351.12 98.53 267.42 299.52 Comparative Example 3 1.98 304.73 95.22 302.79 313.26 Comparative Example 4 2.35 217.62 96.44 308.64 268.75 Comparative Example 5 2.82 332.64 95.92 357.42 327.96

[0089] Since potato flour does not contain gluten protein, after adding 50% potato flour to wheat flour, the quality of potato bread is reduced, and the specific volume is greatly reduced and the hardness is increased, which reduces the consumer acceptance of bread. Reference Examples 2 and 3 add enzyme preparations that can hydrolyze the fiber components in potato dough to bread in order to improve the quality of potato bread. The results show that although the enzyme preparations can increase the specific volume of bread and reduce the hardness of bread to a certain extent, the improvement effect on bread is not ideal. In addition, it can be seen from Table 1 that although the addition of cellulase, pectinase or starch branching enzyme (reference examples 2, 3 and 4) and the addition of potato starch alone (reference example 5) have a significant improvement on the specific volume of potato bread, these methods are far less effective than the combined cellulase, pectinase, starch branching enzyme and potato starch in improving the quality of potato bread. The texture characteristics of the potato bread in Examples 1, 2 and 3 were also greatly improved, wherein the specific volume of the bread in Example 3 increased by 76.71% and the hardness decreased by 60.39% compared with that in Control Example 1.

[0090] Without changing the properties of potato flour, the addition of a single enzyme that strengthens the cross-linking of gluten protein cannot fundamentally solve the destructive effect of potato flour on the gluten protein network structure. It can be seen from the fermentation rheological properties of the dough (Table 5) that there is no significant difference in the gas production of the control and example doughs, indicating that the improvement in bread quality is due to the strengthening of the gluten protein network structure in the dough. Adding cellulase and pectinase to moderately enzymolyze the potato flour, so that the potato flour that was originally wrapped by the cell wall in a large particle agglomeration state can be uniformly dispersed in the gluten network structure, reducing the physical blocking of the insoluble fiber component in the extension process of the gluten protein peptide chain. In addition, the synergistic addition of potato starch further strengthens the dough structure, so that the maximum fermentation height (Hm) and dough gas holding rate (R) of the potato dough in Example 3 are increased by 67.32% and 18.01% respectively compared with the control example 1.

[0091] like Figure 1 As shown, it can be seen more intuitively that compared with other control examples, the improvement of the quality of potato bread in the embodiment is more obvious. The results of adding gluten microstructure show that the addition of cellulase and pectinase can continuously hydrolyze the cellulose and pectin components naturally present in the potato cell wall during the dough kneading process, reducing the destructive effect of the insoluble cellulose component on the gluten protein network structure, and improving the integrity and continuity of the gluten network structure. In addition, after enzymatic hydrolysis and the addition of potato starch, starch granules fill the gluten protein network structure, supporting the dough skeleton structure, and ultimately improving the specific volume and texture of the bread.

[0092] Table 5 Rheological properties of dough fermentation

[0093]

[0094] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. A method for preparing dough by adding a high proportion of potato whole flour, characterized in that: The steps include: (1) using a composite enzyme to enzymatically hydrolyze whole potato flour to obtain enzymatically hydrolyzed dough; (2) The enzymatically hydrolyzed dough is mixed with wheat flour and potato starch, and kneaded to obtain a dough with a high proportion of potato whole flour added.

2. The preparation method according to claim 1, characterized in that: In step (1), the complex enzyme consists of cellulase, pectinase and starch branching enzyme; The added amounts of cellulase, pectinase and starch branching enzyme relative to the dry basis of raw potato whole flour are 0.10-0.35 U / g, 0.10-0.35 U / g and 0.10-0.40 U / g respectively.

3. The preparation method according to claim 1, characterized in that: In step (1), the enzymatic hydrolysis temperature is 45-55° C. and the enzymatic hydrolysis time is 55-65 min.

4. The preparation method according to claim 1, characterized in that: In step (2), the amount of potato starch used is 5-10% of the total mass of raw potato flour and wheat flour.

5. A dough containing a high proportion of whole potato flour prepared by the preparation method according to any one of claims 1 to 4.

6. An application of the dough according to claim 5, characterized in that: For preparing potato bread.

7. A method for making potato bread from the dough of claim 6, characterized in that: The steps include: An emulsifier is added to the dough with a high proportion of potato whole flour, and the potato bread with a high proportion of potato whole flour is prepared after kneading, proofing and baking.

8. The method according to claim 7, characterized in that The emulsifier is sodium stearoyl lactylate, and the dosage is 1-1.5% of the total mass of raw potato flour and wheat flour.

9. The method according to claim 7, characterized in that: One or more of sugar, yeast, milk powder, butter and edible salt are also added to the dough.

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