Processing method of freeze-dried convenient wontons

Abstract

The invention discloses a processing method of freeze-dried convenient wontons. The processing method comprises the following steps: S1, adding modified beet pectin of which the mass is 35-45% of that of raw material flour into the raw material flour, fully mixing and kneading into wonton dough; s2, fermenting the wonton dough obtained in the step S1, and then preparing wontons from the fermented wonton dough and stuffing; and S3, curing the wontons obtained in the step S2, and freeze-drying to prepare the freeze-dried convenient wontons. Wherein the modified beet pectin is prepared by performing enzymolysis on beet pectin through a compound enzyme of galactosidase and arabinosidase, and further mixing with tyrosinase and laccase. The invention relates to the technical field of food processing, beet pectin is introduced into wonton wrappers, and a ternary network based on pectin-pectin, protein-protein and pectin-protein is constructed by using an enzyme catalysis method, so that the toughness and cohesion of the freeze-dried wrappers are improved, and the breakage rate of products is reduced; meanwhile, the branched chain structure of the beet pectin is reduced through enzymatic modification, the hydrophilic performance is improved, and the rehydration rate and the water holding capacity of the product are increased.

Description

Technical Field

[0001] The present invention relates to the technical field of food processing, and more particularly to a method for processing freeze-dried instant wontons. Background Art

[0002] Freeze-dried wontons are made by cooking fresh wontons and then subjecting them to a vacuum freeze-drying process. Freeze-dried wontons largely retain the color, aroma, taste, shape, and nutritional content of the original fresh food. Simply add hot water and wait a few minutes before eating. This processing method meets modern consumers' demands for convenience, quality, and nutrition, and has significant market potential. However, freeze-dried wontons currently face two challenging quality issues: First, the moisture content of freeze-dried wontons is typically less than 4%. Lacking the plasticizing effect of water, the wonton wrappers lack toughness and are extremely hard and brittle, easily breaking during transport and storage, significantly reducing the product's commercial value. Second, the freeze-drying process causes starch recrystallization and aging, which in turn affects the rehydration rate and rehydration rate of the freeze-dried wontons. These two issues have severely hampered the development of the freeze-dried wonton industry. Prior art In the invention patent application with application publication number CN113519772A, a ready-to-eat wonton and its production method are disclosed. The invention patent application discloses a method for preparing wontons. The method improves the water holding capacity of the product to a certain extent by (1) adding hydrophilic colloids such as guar gum and xanthan gum. However, although these colloids have good hydrophilic properties, excessive addition will also destroy the gluten protein structure, increase the softness and slipperiness of the dough, and at the same time, will cause the dough to be easily perforated or even disintegrated. (2) Phosphates are added to improve the water holding capacity of wontons. Although the addition of phosphates can significantly improve the water holding capacity of wonton wrappers, due to the strong water-locking ability of phosphates, it will lead to excessive bound water in the later decomposition stage of the freeze-drying process, taking longer to complete the drying process, resulting in a significant increase in energy consumption. At the same time, excessive phosphates will also bring about odor and be detrimental to product quality. Therefore, how to reduce the breakage rate of freeze-dried wontons and improve the rehydration performance has become an urgent problem to be solved. Summary of the Invention

[0003] An object of the present invention is to provide a processing method for freeze-dried instant wontons, which can significantly reduce the breakage rate of the freeze-dried wontons and increase the rehydration rate and water holding capacity of the product.

[0004] In order to achieve these objects and other advantages of the present invention, according to one aspect of the present invention, the present invention provides a method for processing freeze-dried instant wontons, comprising the following steps: S1. Adding 35-45% of the weight of the raw flour to the raw flour, modifying the beet pectin, and mixing thoroughly to form wonton dough; S2, making wontons with fillings after the wonton dough obtained in step S1 is proofed; S3, cooking the wontons obtained in step S2 and freeze-drying them to prepare the freeze-dried instant wontons; The modified beet pectin is prepared by enzymatic hydrolysis of beet pectin with a complex enzyme of galactosidase and arabinosidase, and then further mixing tyrosinase and laccase.

[0005] Preferably, the specific preparation steps of the modified beet pectin in step S1 are: adding galactosidase and arabinosidase to a beet pectin solution with a mass concentration of 0.8-1.2%, enzymolysis at 30-37°C for 4-6h to obtain a pectin hydrolyzate and cooling it to 2-4°C, then adding laccase and tyrosinase to the pectin hydrolyzate, stirring evenly, to obtain the modified beet pectin.

[0006] Preferably, the enzyme activity concentrations of the β-galactosidase and arabinosidase in the pectin hydrolysate are both 2-6 U / mL.

[0007] Preferably, the preparation process of the wonton dough in step S1 is: based on the weight of the flour, adding 0.8-1.2% of salt, 0.1-0.3% of complex phosphate, 0.1-0.3% of edible alkali, 0.2-0.4% of monoglyceride, 0.2-0.4% of sucrose ester and gluten (quality improver) to the flour to obtain the raw flour, and then adding the modified beet pectin, kneading and stirring to mix it evenly with the raw flour to obtain wonton dough, and keeping the dough temperature below 10°C during the kneading process.

[0008] Preferably, the amount of gluten added and the enzyme activity concentrations of laccase and tyrosinase in the wonton dough are adjusted according to the protein content of the flour, specifically: When the protein content of the flour is greater than 12.5%, the amount of gluten added is 3-5%, the addition ratio of the laccase and tyrosinase is 1:1, and the enzyme activity concentrations of the two in the wonton dough are both 50-200 U / g; When the protein content of the flour is between 9.5% and 12.5%, the amount of gluten added is 5-7%, the addition ratio of laccase and tyrosinase is 2:1, the enzyme activity concentration of laccase in the wonton dough is 80-300 U / g, and the enzyme activity concentration of tyrosinase in the wonton dough is 40-150 U / g; When the protein content of the flour is less than 9.5%, the amount of gluten added is 7-10%, the addition ratio of laccase and tyrosinase is 3:1, the enzyme activity concentration of laccase in the wonton dough is 150-600 U / g, and the enzyme activity concentration of tyrosinase in the wonton dough is 50-200 U / g.

[0009] Preferably, the composite phosphate is selected from at least two of hexametaphosphate, tripolyphosphate and pyrophosphate.

[0010] Preferably, in step S2, the wonton dough is proofed for 15-60 min at a proofing temperature of 30-37°C.

[0011] Preferably, the specific steps of ripening the wontons in step S3 are: steaming the stuffed wontons at normal pressure for 4-6 minutes, and cooling them naturally at room temperature.

[0012] Preferably, the freeze-drying process comprises placing the steamed wontons into a mold, freezing them at -40°C, controlling the freezing time to be 5-7 hours, and placing the completely frozen wonton material into a freeze dryer for freeze-drying.

[0013] Preferably, when freeze drying is performed in a freeze dryer, the temperature of the heating plate of the freeze dryer is set to: first stage: 65-85°C, 6-8 h; second stage: 50-70°C, 8-12 h; third stage, 40-50°C, drying until the moisture content is less than 4%.

[0014] The present invention has at least the following beneficial effects: First, the present invention introduces beet pectin into wonton wrappers, and constructs a ternary network based on pectin-pectin, protein-protein, and pectin-protein through an enzymatic method, thereby improving the toughness and cohesion of the freeze-dried dough wrappers and significantly reducing the breakage rate of freeze-dried wontons; at the same time, the beet pectin side chain structure is reduced through enzymatic modification to improve its hydrophilic properties, thereby increasing the rehydration rate and water holding capacity of the product while participating in the construction of the network.

[0015] Second, the present invention significantly improves the rehydration rate and water-holding capacity of wonton wrappers by adding sugar beet pectin, modified with galactosidase and arabinosidase, to the dough. Pectin is a heteropolysaccharide widely found in the primary and middle lamellae of plant cell walls. Sugar beet pectin is extracted and produced from sugar production byproducts and is relatively inexpensive. As a typical pectin, sugar beet pectin has excellent hydrophilicity. Adding it to the dough significantly increases the system's hydration rate and water-holding capacity, which is reflected macroscopically in an improved rehydration rate and rehydration ratio of the wonton wrapper. Sugar beet pectin is rich in galactose and arabinose side chains. The steric hindrance created by these side chains hinders the formation of a cross-linked network, and its hydrophilicity is not as strong as that of the galacturonic acid backbone. Therefore, the present invention utilizes galactosidase and arabinosidase to degrade some of these side chains, which not only improves the hydrophilicity of the wonton wrapper after the addition of sugar beet pectin, but also facilitates the participation of sugar beet pectin in the formation of the covalent cross-linked network.

[0016] Third, the present invention constructs an internal cross-linked network of wonton wrappers through the combined treatment of tyrosinase and laccase, which significantly increases the toughness and strength of freeze-dried wonton wrappers, greatly reduces the breakage rate of freeze-dried wontons in the freeze-drying, packaging, transportation and consumption links, improves the appearance quality of the product, and effectively solves the problem of easy breakage of wontons after freeze-drying. On the basis of adding gluten to strengthen the gluten network, the present invention further utilizes the following enzyme-catalyzed enhanced cross-linking principle: First, laccase (laccase, EC1.10.3.2) is a copper-containing polyphenol oxidase that can catalyze the oxidation of phenols and aromatic compounds to generate corresponding benzoquinones, while reducing molecular oxygen to water accompanied by electron transfer. Beet pectin molecules contain a large amount of ferulic acid esters. The cross-linking reaction catalyzed by laccase is based on catalyzing the formation of free radicals from ferulic acid esters, which triggers further reactions to achieve molecular cross-linking (see the specific reaction mechanism). Figure 3 ). Beet pectin ferulic acid ester cross-linking sites are numerous and the covalent bond cross-linking strength is high, which plays a great role in improving the toughness and cohesion of freeze-dried dough. Secondly, tyrosinase (EC 1.14.18.1) is a copper-containing oxidoreductase that belongs to the copper type III protein family. Tyrosinase can oxidize tyrosine in the side chain of proteins to quinone, which can further cross-link with lysine, tyrosine and cysteine ​​residues in the protein, but these secondary cross-links are highly random and have relatively few cross-linking sites. Therefore, the addition of tyrosinase can strengthen the mutual cross-linking between gluten proteins, but this effect is weaker in both intensity and effect than the laccase-catalyzed pectin cross-linking. Furthermore, laccase not only catalyzes the formation of free radicals from ferulic acid esters on beet pectin but also catalyzes the formation of free radicals from the tyrosine benzene rings of gluten proteins. Further reactions between the two can also lead to crosslinking, achieving crosslinking and nesting of the beet pectin network and the gluten protein network. This pectin-protein crosslinking allows for the fusion and rigid nesting of the pectin and protein networks, which has a certain effect on strengthening the toughness and cohesion of freeze-dried wontons. However, compared to the first two interactions, the crosslinking sites are fewer, resulting in a relatively smaller strength and effect. Overall, the combined and additive effects of the numerous covalent crosslinks formed by these three mechanisms form a network with high strength and toughness within the dough. Because the crosslinks are based on valence bonds, the loss of water after freeze-drying does not affect the crosslinking state of the network. This network imparts enhanced cohesiveness and flexibility to the freeze-dried dough, significantly reducing the breakage rate of freeze-dried wontons.

[0017] Other advantages, objectives and features of the present invention will be reflected in part from the following description and will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 11 is a comparison of the appearance of wonton products prepared in Example 2 and Comparative Example 15; Figure 2 This is a process flow chart of a method for processing freeze-dried instant wontons according to a technical solution of the present invention; Figure 3 Schematic diagram of laccase-catalyzed cross-linking of ferulic acid esters in sugar beet pectin. DETAILED DESCRIPTION

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can implement the invention with reference to the description.

[0020] It should be understood that terms such as “having”, “including” and “comprising” used herein do not preclude the existence or addition of one or more other elements or combinations thereof.

[0021] <Example 1> A method for processing freeze-dried instant wontons comprises the following steps: (1) Preparation of pectin hydrolysate: β-galactosidase and arabinosidase (the enzyme activity concentration in the pectin hydrolysate was 2 U / mL) were added to a 0.8% sugar beet pectin solution and enzymatic hydrolysis was carried out at 30°C for 4 h to obtain pectin hydrolysate.

[0022] (2) Preparation of raw flour: Based on the weight of flour, 0.8% of table salt, 0.05% of hexametaphosphate, 0.05% of tripolyphosphate, 0.1% of edible alkali, 0.2% of monoglyceride, 0.2% of sucrose ester and 3% of gluten (quality improver) were added to high-gluten wheat flour (protein content > 12.5%) to obtain raw flour.

[0023] (3) Preparation of modified beet pectin solution: Take pectin hydrolysate, cool it to 2°C, then add laccase and tyrosinase to the pectin hydrolysate. The addition ratio of laccase and tyrosinase is 1:1, and the enzyme activity concentration of both is 50 U / g (the denominator weight is based on the final dough weight). Stir evenly to obtain the modified beet pectin solution.

[0024] (4) Preparation of wonton dough: Add modified beet pectin solution (35% by weight of the raw flour) and mix it with the raw flour to obtain wonton dough. During the mixing process, the dough temperature is always kept below 10°C.

[0025] (5) Proofing and cross-linking: After kneading, let the dough rise in a dough mixer for 15 minutes at a temperature of 30°C.

[0026] (6) Rolling into wrappers: Put the dough after proofing into an automatic rolling machine and roll it into wonton wrappers.

[0027] (7) Wrapping and forming: Prepare the specific wonton filling and use the wonton wrappers to wrap wontons. This process can be done automatically by machine or manually.

[0028] (8) Steaming and maturation: Steam the wrapped wontons under normal pressure for 4 min and cool them naturally at room temperature.

[0029] (9) Pre-freezing in molds: Place the cooked wontons into molds, control the time the materials wait in the tray for entering the cold storage to be within 30 minutes, freeze them at -40°C, and control the freezing time to be about 5 hours to ensure that the materials are completely frozen.

[0030] (10) Vacuum freeze drying: The frozen wonton material is pushed into the freeze drying chamber for freeze drying. The temperature of the heating plate of the freeze dryer can be set as follows: the first stage: 65°C, 8 h; the second stage: 50°C, 12 h; the third stage, 40°C, drying until the moisture content is less than 4%; (11) Finished product packaging: After freeze-drying, the freeze-dried wontons are taken out from the mold and packaged to obtain the finished product.

[0031] <Example 2> A method for processing freeze-dried instant wontons comprises the following steps: (1) Preparation of pectin hydrolysate: β-galactosidase and arabinosidase (the enzyme activity concentration in the pectin hydrolysate was 4 U / mL) were added to a 1.0% sugar beet pectin solution and enzymatic hydrolysis was carried out at 35°C for 5 h to obtain pectin hydrolysate.

[0032] (2) Preparation of raw flour: Based on the weight of flour, 1.0% of salt, 0.1% of tripolyphosphate, 0.1% of pyrophosphate, 0.2% of edible alkali, 0.3% of monoglyceride, 0.3% of sucrose ester and 4% of gluten (quality improver) were added to high-gluten wheat flour (protein content>12.5%) to obtain raw flour.

[0033] (3) Preparation of modified beet pectin solution: Take pectin hydrolysate, cool it to 3°C, then add laccase and tyrosinase to the pectin hydrolysate. The addition ratio of laccase and tyrosinase is 1:1, and the enzyme activity concentration of both is 100 U / g (the denominator weight is based on the final dough weight). Stir evenly to obtain the modified beet pectin solution.

[0034] (4) Preparation of wonton dough: Add modified beet pectin solution (40% by weight of the raw flour) and mix it with the raw flour to obtain wonton dough. During the mixing process, the dough temperature is always kept below 10°C.

[0035] (5) Proofing and cross-linking: After kneading, let the dough rise in a dough mixer for 30 min at a temperature of 35°C.

[0036] (6) Rolling into wrappers: Put the dough after proofing into an automatic rolling machine and roll it into wonton wrappers.

[0037] (7) Wrapping and forming: Prepare the specific wonton filling and use the wonton wrappers to wrap wontons. This process can be done automatically by machine or manually.

[0038] (8) Steaming and maturation: Steam the wrapped wontons under normal pressure for 5 minutes and cool them naturally at room temperature.

[0039] (9) Pre-freezing in molds: Place the cooked wontons into molds, control the time the materials wait in the tray for entering the cold storage to be within 30 minutes, freeze them at -40°C, and control the freezing time to be about 6 hours to ensure that the materials are completely frozen.

[0040] (10) Vacuum freeze drying: Push the frozen wonton material into the freeze drying chamber for freeze drying. The temperature of the heating plate of the freeze dryer can be set as follows: first stage: 75℃, 7 h; second stage: 60℃, 10 h; third stage, 45℃, drying until the moisture content is less than 4%; (11) Finished product packaging: After freeze-drying, the freeze-dried wontons are taken out from the mold and packaged to obtain the finished product.

[0041] <Example 3> A method for processing freeze-dried instant wontons comprises the following steps: (1) Preparation of pectin hydrolysate: β-galactosidase and arabinosidase (the enzyme activity concentration in the pectin hydrolysate was 6 U / mL) were added to a 1.2% sugar beet pectin solution and enzymatic hydrolysis was carried out at 37°C for 6 h to obtain pectin hydrolysate.

[0042] (2) Preparation of raw flour: Based on the weight of flour, 1.2% of table salt, 0.1% of hexametaphosphate, 0.1% of tripolyphosphate, 0.1% of pyrophosphate, 0.3% of edible alkali, 0.4% of monoglyceride, 0.4% of sucrose ester and 5% of gluten (quality improver) were added to high-gluten wheat flour (protein content>12.5%) to obtain raw flour.

[0043] (3) Preparation of modified beet pectin solution: pectin hydrolysate was taken and cooled to 4°C. Laccase and tyrosinase were then added to the pectin hydrolysate in a ratio of 1:1. The enzyme activity concentrations of both were 200 U / g (the denominator weight was calculated based on the final dough weight). The mixture was stirred evenly to obtain the modified beet pectin solution.

[0044] (4) Preparation of wonton dough: Add modified beet pectin solution (45% by weight of the raw flour) and mix it with the raw flour to obtain wonton dough. The dough temperature is kept below 10°C during the mixing process.

[0045] (5) Proofing and cross-linking: After kneading, the dough was proofed in a dough mixer for 60 min at a proofing temperature of 37°C.

[0046] (6) Rolling into wrappers: Put the dough after proofing into an automatic rolling machine and roll it into wonton wrappers.

[0047] (7) Wrapping and forming: Prepare the specific wonton filling and use the wonton wrappers to wrap wontons. This process can be done automatically by machine or manually.

[0048] (8) Steaming and maturation: Steam the wrapped wontons under normal pressure for 6 minutes and cool them naturally at room temperature.

[0049] (9) Pre-freezing in molds: Place the cooked wontons into molds, control the time the materials wait in the tray for entering the cold storage to be within 30 minutes, freeze them at -40°C, and control the freezing time to be about 7 hours to ensure that the materials are completely frozen.

[0050] (10) Vacuum freeze drying: The frozen wonton material is pushed into the freeze drying chamber for freeze drying. The temperature of the heating plate of the freeze dryer can be set as follows: the first stage: 85℃, 6 h; the second stage: 70℃, 8 h; the third stage, 50℃, drying until the moisture content is less than 4%; (11) Finished product packaging: After freeze-drying, the freeze-dried wontons are taken out from the mold and packaged to obtain the finished product.

[0051] <Example 4> The difference from Example 2 is: (2) Preparation of raw flour: Based on the weight of flour, 1.2% of salt, 0.1% of hexametaphosphate, 0.1% of tripolyphosphate, 0.1% of pyrophosphate, 0.3% of edible alkali, 0.4% of monoglyceride, 0.4% of sucrose ester and 7% of gluten were added to medium-gluten wheat flour (protein content between 9.5% and 12.5%) to obtain raw flour.

[0052] (3) Preparation of modified beet pectin solution: Take the pectin hydrolysate, cool it to 4°C, then add 300 U / g of laccase and 150 U / g of tyrosinase to the pectin hydrolysate (the denominator weight is based on the final dough weight), stir well, and the modified beet pectin solution can be obtained.

[0053] The remaining steps are consistent with Example 2.

[0054] <Example 5> The difference from Example 2 is: (2) Preparation of raw flour: Based on the weight of flour, 1.2% of salt, 0.1% of hexametaphosphate, 0.1% of tripolyphosphate, 0.1% of pyrophosphate, 0.3% of edible alkali, 0.4% of monoglyceride, 0.4% of sucrose ester and 10% of gluten were added to low-gluten wheat flour (protein content <9.5%) to obtain raw flour.

[0055] (3) Preparation of modified beet pectin solution: Take the pectin hydrolysate, cool it to 4°C, then add 600 U / g of laccase and 200 U / g of tyrosinase to the pectin hydrolysate (the denominator weight is based on the final dough weight), stir well, and the modified beet pectin solution can be obtained.

[0056] The remaining steps are consistent with Example 2.

[0057] Comparative Example 1 The difference from Example 2 is: Omit (1) and (3), and replace the modified beet pectin solution with an equal amount of water in step (4).

[0058] The remaining steps are consistent with Example 2.

[0059] Comparative Example 2 The difference from Example 2 is: No laccase was added in step (3).

[0060] The remaining steps are consistent with Example 2.

[0061] Comparative Example 3 The difference from Example 2 is: Tyrosinase was not added in step (3).

[0062] The remaining steps are consistent with Example 2 Comparative Example 4 The difference from Example 2 is: Omit step (3) and replace the modified beet pectin solution in step (4) with an equal amount of pectin enzymatic hydrolysate.

[0063] The remaining steps are consistent with Example 2.

[0064] Comparative Example 5 The difference from Example 2 is: Omit step (1) and replace the pectin enzymatic hydrolysate in step (3) with beet pectin solution.

[0065] The remaining steps are consistent with Example 2.

[0066] Comparative Example 6 The difference from Example 2 is: The sugar beet pectin was replaced by an equal amount of commercial low-ester citrus pectin, steps (1) and (3) were omitted, and the modified sugar beet pectin solution in step (4) was replaced by an equal amount of commercial low-ester citrus pectin solution.

[0067] The remaining steps are consistent with Example 2.

[0068] Comparative Example 7 The difference from Example 2 is: In step (1), beet pectin was replaced with an equal amount of commercial low-ester citrus pectin. In step (3), laccase and tyrosinase were not added, and instead 20 mmol / mL calcium chloride (CaCl2) and 50 mmol / mL gluconolactone (GDL) were added to the pectin hydrolysate, with the concentrations calculated based on the volume of the final pectin solution.

[0069] The remaining steps are consistent with Example 2.

[0070] Comparative Example 8 The difference from Comparative Example 6 is that the commercial low-ester citrus pectin is replaced with an equal amount of commercial low-ester apple pectin, and the remaining steps are the same as those of Comparative Example 6.

[0071] Comparative Example 9 The difference from Comparative Example 7 is that the commercial low-ester citrus pectin is replaced with an equal amount of commercial low-ester apple pectin, and the remaining steps are the same as those of Comparative Example 7.

[0072] Comparative Example 10 The difference from Comparative Example 6 is that the commercial low-ester citrus pectin is replaced with an equal amount of commercial carrageenan, and the remaining steps are the same as those of Comparative Example 6.

[0073] Comparative Example 11 The difference from Comparative Example 6 is that the commercial low-ester citrus pectin is replaced with an equal amount of commercial xanthan gum, and the remaining steps are the same as those of Comparative Example 6.

[0074] Comparative Example 12 The difference from Comparative Example 6 is that the commercial low-ester citrus pectin is replaced with an equal amount of commercial gelatin, and the remaining steps are the same as those of Comparative Example 6.

[0075] Comparative Example 13 The difference from Example 2 is: In step (2), high-gluten wheat flour (protein content > 12.5%) is replaced with an equal amount of medium-gluten wheat flour (protein content between 9.5% and 12.5%).

[0076] The remaining steps are consistent with Example 2.

[0077] Comparative Example 14 The difference from Example 2 is: In step (2), high-gluten wheat flour (protein content > 12.5%) was replaced with an equal amount of low-gluten wheat flour (protein content < 9.5%).

[0078] The remaining steps are consistent with Example 2.

[0079] Comparative Example 15 The difference from Example 2 is: Steps (1) to (3) are omitted. In step (4), an equal amount of water is directly added to the high-gluten wheat flour and the dough is stirred to form wonton dough. No other substances are added to the dough.

[0080] <Comparative Analysis of Wonton Product Quality> Breakage rate determination method The packaged freeze-dried wonton samples from each example and comparative example were placed on a shaker, secured with a rubber band, and vibrated at 60 rpm for 30 minutes. The packages were opened, and the wonton main body fragments were separated. The wonton main body and wonton debris were weighed separately. The percentage (%) of the product debris weight to the total product weight was calculated as the breakage rate.

[0081] (1); in, P is the oscillation breakage rate of wontons, %; m 1 is the mass of wonton crumbs after oscillation, g; m 2 is the mass of the main part of the wonton after oscillation, g.

[0082] Rehydration time determination method The freeze-dried wontons prepared in each embodiment and comparative example were placed in an insulated container, and boiling water of about 8 times its mass was added. The container was immediately covered and a stopwatch was used to record the time. When the softened wontons were clamped with a glass sheet and the gelatinization state was observed without an obvious hard core, the rehydration time was recorded.

[0083] Rehydration ratio determination method Weigh the freeze-dried wonton samples prepared in each embodiment and comparative example m 1. Place in a beaker, add boiling water to just immerse the sample, cover and seal, rehydrate for 5 minutes, remove and drain, and use filter paper to absorb excess water on the surface, and weigh. m 2. Parallel measurements were performed 3 times and the average value was taken. The results were calculated according to formula (2): (2); Where, F is the rehydration ratio; m 1 is the mass of the sample before rehydration, g;m 2 is the mass of the sample after rehydration, g.

[0084] The above measurement results are shown in Table 1.

[0085] Table 1 Breakage rate / % Rehydration time / s Rehydration ratio Example 1 3.5 276 3.09 Example 2 2.6 269 3.15 Example 3 2.4 252 3.25 Example 4 2.7 269 3.14 Example 5 2.6 270 3.13 Comparative Example 1 11.2 425 2.64 Comparative Example 2 7.1 324 2.99 Comparative Example 3 6.4 310 2.96 Comparative Example 4 9.7 344 2.73 Comparative Example 5 4.0 303 3.06 Comparative Example 6 9.4 337 2.80 Comparative Example 7 6.8 359 2.91 Comparative Example 8 9.6 339 2.75 Comparative Example 9 7.1 363 2.88 Comparative Example 10 9.3 333 2.82 Comparative Example 11 9.2 330 2.85 Comparative Example 12 9.7 356 2.69 Comparative Example 13 3.8 288 3.08 Comparative Example 14 4.0 292 3.07 Comparative Example 15 13.4 495 2.52 As can be seen from the results in Table 1, compared with other comparative examples, the freeze-dried instant wontons produced using the processing method of the present invention in Examples 1 to 5 have a low breakage rate, a short rehydration time, and a high rehydration ratio, effectively solving the problems of poor toughness, easy breakage, and poor rehydration performance of wonton wrappers in the prior art. A detailed analysis is as follows: Example 1: The freeze-dried wontons prepared in this example have a low breakage rate, a fast rehydration rate, and a high moisture content. The main reasons for this excellent quality are that, on the one hand, beet pectin forms a highly strong cross-linked network through covalent bonds, and on the other hand, tyrosinase catalyzes the formation of cross-links in gluten proteins. Simultaneously, free radicals formed by ferulic acid in beet pectin can also attack the tyrosine benzene ring, thereby forming cross-links between the pectin and protein networks. Based on these cross-links, a strong network based on covalent bonds is formed in the dough. This significantly improves the toughness and cohesion of the freeze-dried wonton wrapper, making it less prone to breakage under oscillation conditions and reducing the product breakage rate. Furthermore, the addition of highly hydrophilic and active pectin with de-branched chains, along with gluten proteins, phosphates, etc., greatly improves the hydrophilicity of the wonton wrapper, resulting in a higher moisture content after rehydration. Furthermore, the high-strength pectin-protein network provides a large number of moisture channels for the wonton wrapper, which facilitates moisture migration and thus significantly improves the rehydration rate of the wonton wrapper.

[0086] Example 2: The freeze-dried wontons prepared in this example, like those in Example 1, also have a low breakage rate, a faster rehydration rate, and a higher moisture ratio. Since this solution increases the proportion of beet pectin and the concentration of branching enzymes compared to Example 1, the product contains more beet pectin with a higher degree of linearization and better hydrophilicity. Therefore, the rehydration time is faster and the rehydration ratio is higher than that of Comparative Example 1. On the other hand, the concentrations of laccase and tyrosinase are increased, which is beneficial for catalyzing the formation of more covalent cross-links between pectin and protein, thereby increasing network strength and further improving the toughness and cohesion of the freeze-dried wonton wrappers. Therefore, the breakage rate is lower.

[0087] Example 3: The freeze-dried wontons prepared in this example have the lowest breakage rate, the fastest rehydration rate and the highest moisture ratio compared to Examples 1 and 2, and are the optimal solution of the present invention. This is due to the further increase in the sugar beet pectin content, as well as the improvement in the activity of pectin debranching enzymes and cross-linking enzymes, and the principle of obtaining better quality is the same as that of Examples 1 and 2. However, compared with Example 2, the breakage rate and rehydration performance of this example are not as much improved as those of Example 2 compared with Example 1, indicating that further increasing the pectin concentration and strengthening cross-linking cannot infinitely improve product quality. In fact, the present invention also attempts to further increase the sugar beet pectin. Too much pectin will cause the wonton wrapper to have a soft taste, so the solution of adding more pectin than in Example 3 is not suitable.

[0088] Examples 4 and 5: In Examples 4 and 5, medium-gluten flour and low-gluten flour, respectively, were used instead of high-gluten flour. The resulting products showed comparable performance to that of Example 2. Therefore, the processing method of the present invention can be adapted to different types of flour by rationally adjusting the amount and ratio of gluten, laccase, and tyrosinase based on the protein content of the flour, thereby increasing the flexibility and applicability of the processing method. The medium-gluten gluten used in Example 4 has a relatively weak ability to form a cross-linked network. Increasing the gluten content effectively supplements protein and enhances gluten network formation. The addition of gluten enables better gluten formation during kneading, improving the dough's plasticity and extensibility. Furthermore, the addition of laccase and tyrosinase in a 2:1 ratio creates a differentiated enzymatic reaction. Laccase exhibits greater activity in catalyzing the cross-linking reaction. A higher laccase ratio more effectively promotes cross-linking between gluten proteins and pectin, compensating for the deficiencies in the gluten network of medium-protein flour. Tyrosinase, on the other hand, plays a supporting role, synergizing with laccase to enhance the cross-linking effect, resulting in a dough with improved toughness and rehydration properties. In Example 5, low-gluten flour was used, which made it almost impossible to form an effective gluten network on its own. Adding more gluten was the key to building the gluten network. A large amount of gluten can provide sufficient protein raw materials for the formation of gluten, giving the dough basic molding and processing properties. Laccase and tyrosinase were added in a ratio of 3:1. The high proportion and high activity of laccase can strongly catalyze the cross-linking reaction of gluten protein and modified beet pectin on the basis of the gluten formed by gluten, forming a more compact and stable network structure. This not only significantly improves the toughness and strength of the dough, but also improves its rehydration properties, allowing the freeze-dried wontons made with low-protein flour to maintain a good taste and shape after rehydration.

[0089] Comparative Example 1: Since no beet pectin was added to Comparative Example 1, covalent bonds could not be formed through laccase cross-linking. This resulted in the freeze-dried wonton wrappers lacking a sufficiently strong three-dimensional network to provide toughness, resulting in a relatively high breakage rate. At the same time, the breakage rate of Comparative Example 1 was still lower than that of the conventional process. This is because gluten protein can also form certain covalent bonds under the action of tyrosinase, which has a certain effect on enhancing the network strength in the wonton wrappers and reducing the breakage rate of wontons. Due to the lack of beet pectin or other polysaccharides to provide hydrophilicity, the wontons have a longer rehydration time and a lower rehydration ratio.

[0090] Comparative Example 2: This comparative example does not add laccase, which prevents the beet pectin from forming a crosslink based on ferulic acid esters. Therefore, the strength of the wontons is not as good as that of Examples 1-3. At the same time, due to the lack of a sufficient three-dimensional network to support the water diffusion network, the rehydration time is relatively long and the rehydration ratio is low. Compared with Comparative Example 1, both do not have a crosslinked network based on beet pectin, but the breakage rate of Comparative Example 2 is significantly lower than that of Comparative Example 1. This is because Comparative Example 2 still adds tyrosinase, and there is a covalent crosslink between gluten proteins catalyzed by tyrosinase, which also has a certain degree of network strengthening effect, which reduces the breakage rate of the product and improves the rehydration performance.

[0091] Comparative Example 3: This comparative example does not add tyrosinase. Unlike Comparative Example 2, this comparative example does not form a gluten protein network based on tyrosinase catalysis, but does have a beet pectin cross-linking network based on laccase catalysis. In comparison, the breakage rate of Comparative Example 3 is slightly lower than that of Comparative Example 1, and the rehydration performance is also slightly better than that of Comparative Example 2. This is because there are more ferulic acid cross-linking sites on beet pectin than on gluten protein. Therefore, the constructed beet pectin cross-linking network contributes more to reducing the breakage rate than the gluten protein cross-linking network. From this comparison, it can be seen that adding beet pectin and catalyzing its cross-linking is more effective than adding gluten protein and tyrosinase to enhance the internal network strength of wonton dough, which is also an innovation of the present invention.

[0092] Comparative Example 4: This comparative example lacks both laccase and tyrosinase, which is equivalent to the lack of both beet pectin-based and gluten-based covalent cross-linked networks. Therefore, this example is equivalent to simply adding beet pectin as a thickener and hydrophilic improver. However, the addition of polysaccharides can also provide more high-molecular substances to participate in the construction of the original gluten network, which is equivalent to the effect of simply adding pectin, carrageenan, xanthan gum, and gelatin from other sources. Their estimated breakage rate is generally better than that of Comparative Example 1, which does not add beet pectin.

[0093] Comparative Example 5: This comparative example did not add galactosidase and arabinanase, meaning the branched structure of the beet pectin was not modified by excision. Beet pectin is a pectin with a relatively rich branched structure, primarily composed of neutral sugars such as arabinan and galactan. The steric hindrance created by the branches hinders crosslinking between beet pectin molecules. Furthermore, the presence of neutral sugars reduces the pectin's hydrophilicity to a certain extent. Since the branches were not treated with enzymes to cleave the branches, these branches reduced the strength and integrity of the pectin network and also decreased its hydrophilicity. This is reflected in the slightly lower breakage rate of the product in Comparative Example 4 than in Examples 1-3, as well as a slightly longer rehydration time and a significantly lower moisture content.

[0094] Comparative Example 6: This comparative example differs from the examples in that no beet pectin was added, and thus no covalent cross-linked network based on beet pectin was constructed. Instead, only a single hydrophilic colloid, commercial low-ester citrus pectin, was added. The results were comparable to those of Comparative Example 4, which lacked the addition of laccase and tyrosinase. The added beet pectin, acting solely as a polysaccharide and acting as a thickener and hydrophilizing agent, was therefore comparable to those of Comparative Example 4. Therefore, the improvements in breakage rate, rehydration time, and rehydration ratio achieved in Comparative Example 6 were comparable to those achieved in Comparative Example 4.

[0095] Comparative Examples 8, 10, 11 and 12: Commercial apple low-ester pectin, carrageenan, xanthan gum and gelatin were added respectively. The quality formation principle and the improvement effect on breakage rate and rehydration characteristics were similar to those of Comparative Examples 6 and 4.

[0096] Comparative Example 7, Comparative Example 9: These two comparative examples and Comparative Example 6, Comparative Example 9 both added citrus low-ester pectin and apple low-ester pectin, respectively, but the working principles of the two are different. Comparative Example 6, Comparative Example 8 is equivalent to adding a single pectin, simply exerting the effect of a thickener and a hydrophilic agent, but Comparative Example 7, Comparative Example 9 simultaneously added calcium chloride and gluconolactone to induce pectin to form an ionic bond based on a calcium ion bridge, thereby also allowing the two pectins to form a crosslinking to form a hydrophilic colloid gel. However, the bond energy of the pectin gel based on the ionic bond is significantly lower than that of the covalent bond, so the gel strength is far from reaching the network system based on the covalent crosslinking of ferulic acid esters formed based on laccase catalysis. This is reflected in the change in quality, that is, the improvement effect of Comparative Example 7 and Comparative Example 9 on the breakage rate and rehydration characteristics of wontons is significantly better than that of Comparative Example 8, Comparative Example 10, Comparative Example 11, and Comparative Example 12, which only added polysaccharides, but is indeed significantly lower than the effect of the embodiment of the present invention.

[0097] Comparative Examples 13 and 14: In these two comparative examples, medium-gluten flour and low-gluten flour, respectively, were used to replace the high-gluten flour in Example 2. For both medium-gluten flour and low-gluten flour, only 4% gluten was added, which failed to fully strengthen the gluten network. This weak gluten network caused the wonton wrappers to break easily during molding and processing, and also lacked chewiness after rehydration, affecting the overall product quality. Furthermore, the use of a 1:1 ratio of laccase and tyrosinase prevented the enzymes from fully catalyzing their effects, resulting in suboptimal cross-linking and limited improvements in the wrappers' toughness and rehydration properties.

[0098] Comparative Example 15: This comparative example adopts conventional technology and uses high-gluten flour to make freeze-dried wontons. Neither beet pectin is added to construct a covalent bond network, nor are quality improvers such as gluten, phosphates, and esters added. Due to the lack of a sufficiently strong cross-linking network to maintain the toughness and cohesion of the freeze-dried wonton wrappers, the freeze-dried wontons are severely damaged after oscillation; on the other hand, due to the lack of a three-dimensional network provided by polysaccharides and proteins as a moisture channel, and the lack of hydrophilic substances such as polysaccharides to improve the water absorption capacity, the freeze-dried wonton wrapper has a dense structure and a high degree of starch aging, which makes the rehydration rate of the comparative example product extremely slow and the rehydration ratio is also very low.

[0099] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the description and implementation methods. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for processing freeze-dried instant wontons, characterized in that: The following steps are involved: S1. Adding 35-45% of the weight of the raw flour to the raw flour, modifying the beet pectin, and mixing the raw flour to form wonton dough; S2, making wontons with fillings after the wonton dough obtained in step S1 is proofed; S3, steaming and ripening the wontons obtained in step S2 and then freeze-drying them to prepare the freeze-dried instant wontons; The modified beet pectin is prepared by enzymolysis of beet pectin by using a composite enzyme of galactosidase and arabinosidase, and then further mixing tyrosinase and laccase.

2. The method for processing freeze-dried instant wontons according to claim 1, characterized in that: The specific preparation steps of the modified beet pectin in step S1 are: adding galactosidase and arabinosidase to a beet pectin solution with a mass concentration of 0.8-1.2%, enzymolysis at 30-37°C for 4-6 hours to obtain a pectin hydrolyzate and cooling it to 2-4°C, then adding laccase and tyrosinase to the pectin hydrolyzate, stirring evenly, and then obtaining the modified beet pectin.

3. The method for processing freeze-dried instant wontons according to claim 2, characterized in that: The enzyme activity concentrations of the β-galactosidase and the arabinosidase in the pectin hydrolysate are both 2-6 U / mL.

4. The method for processing freeze-dried instant wontons according to claim 3, characterized in that: The preparation process of the wonton dough in step S1 is as follows: based on the weight of the flour, 0.8-1.2% of salt, 0.1-0.3% of complex phosphate, 0.1-0.3% of edible alkali, 0.2-0.4% of monoglyceride, 0.2-0.4% of sucrose ester and gluten are added to the flour to obtain the raw flour, and then the modified beet pectin is added, and the dough is stirred to mix it evenly with the raw flour to obtain the wonton dough, and the dough temperature is always kept below 10°C during the kneading process.

5. The method for processing freeze-dried instant wontons according to claim 4, characterized in that: According to the protein content of the flour, the amount of gluten added and the enzyme activity concentrations of laccase and tyrosinase in the wonton dough are adjusted, specifically: When the protein content of the flour is greater than 12.5%, the amount of gluten added is 3-5%, the addition ratio of laccase and tyrosinase is 1:1, and the enzyme activity concentrations of both in the wonton dough are 50-200 U / g; When the protein content of the flour is between 9.5% and 12.5%, the amount of gluten added is 5-7%, the addition ratio of laccase and tyrosinase is 2:1, the enzyme activity concentration of laccase in the wonton dough is 80-300 U / g, and the enzyme activity concentration of tyrosinase in the wonton dough is 40-150 U / g; When the protein content of the flour is less than 9.5%, the amount of gluten added is 7-10%, the addition ratio of laccase and tyrosinase is 3:1, the enzyme activity concentration of laccase in the wonton dough is 150-600 U / g, and the enzyme activity concentration of tyrosinase in the wonton dough is 50-200 U / g.

6. The method for processing freeze-dried instant wontons according to claim 4, characterized in that: The composite phosphate is selected from at least two of hexametaphosphate, tripolyphosphate and pyrophosphate.

7. The method for processing freeze-dried instant wontons according to claim 1, characterized in that: In step S2, the wonton dough is proofed for 15-60 min at a proofing temperature of 30-37°C.

8. The method for processing freeze-dried instant wontons according to claim 1, characterized in that: The specific steps of ripening the wontons in step S3 are: steaming the stuffed wontons at normal pressure for 4-6 minutes, and cooling them naturally at room temperature.

9. The method for processing freeze-dried instant wontons according to claim 1, characterized in that: The specific steps of freeze drying are: putting the steamed wontons into a mold, freezing them at -40°C, controlling the freezing time to be 5-7 hours, and placing the completely frozen wonton material in a freeze dryer for freeze drying.

10. The method for processing freeze-dried instant wontons according to claim 8, characterized in that: When freeze drying is performed in a freeze dryer, the temperature of the heating plate of the freeze dryer is set to the first stage: 65-85° C., 6-8 h; The second stage: 50-70℃, 8-12 h, the third stage, 40-50℃, drying until the moisture content is less than 4%.

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