A method for preparing a noodle rich in flavonoids and soluble dietary fiber by adding asparagus

Abstract

The application discloses a method for preparing a kind of noodles rich in flavonoids and soluble dietary fiber by adding asparagus, and relates to the field of food processing.The application is processed by juicing treatment on fresh non-commercial asparagus or asparagus primary processing waste, and the macromolecular pectin in asparagus juice is degraded to form small molecular pectin with more bioactivity by the method of enzymolysis.In addition, the residues are degraded by adopting active oxygen degradation combined with transient pressure reduction burst treatment technology, flavonoids in the residues are fully released, the content of soluble dietary fiber is improved, and the noodles are prepared by using the asparagus noodles, so that the noodles with good quality are prepared, and the content of flavonoids and dietary fiber in the noodles is improved.

Description

Technical Field

[0001] The invention relates to the field of food processing, and in particular to a method for preparing noodles rich in flavonoids and soluble dietary fiber by adding asparagus. Background Art

[0002] Asparagus (Asparagus officinalis Linn.), also known as asparagus, sulphur-leaved asparagus, asparagus, fine-leaved asparagus, bamboo shoots, and reed tips, is a perennial herbaceous plant in the genus Asparagus of the Liliaceae family. my country's asparagus cultivation area reaches approximately 220,000 mu (approximately 16,000 hectares), with an annual production of approximately 1.8 million tons, accounting for 60% of the world's total. Asparagus is highly nutritious, with a vitamin content 2 to 5 times that of other vegetables, earning it the nickname "king of vegetables." Fresh asparagus is highly susceptible to mechanical damage during harvesting, and the base cut and tips are susceptible to microbial contamination. Furthermore, the highly active physiological metabolism of harvested asparagus makes it extremely vulnerable to storage. During distribution and storage, it is prone to dehydration, mold, discoloration, and lignification. It can only be stored for 3 to 5 days at room temperature and for only one week at low temperatures. Therefore, when asparagus is on the market in large quantities, it is difficult to solve the problem of unsold asparagus by simply selling it fresh. In addition, in order to ensure that asparagus can be supplied all year round, asparagus is mainly processed into canned and quick-frozen products.

[0003] During the primary processing, storage, and transportation of asparagus, aged, unsightly, deformed, diseased, and loose shoots must be removed. These scraps account for 20-50% of the raw material. While their nutritional content is comparable to commercial shoots, they are often discarded as waste, causing significant environmental pollution and resource waste. The functional components of asparagus are flavonoids and dietary fiber, with flavonoids primarily including quercetin, rutin, and kaempferol. Flavonoids are a class of compounds recognized for their antioxidant properties, including suppressing hypertension, hyperlipidemia, and hyperglycemia, scavenging free radicals, providing anti-aging, radiation protection, antibacterial, and anti-cancer properties, and inhibiting cancer cell growth. Dietary fiber is a substance that cannot be absorbed by the human body but has important physiological benefits. It is divided into two types: soluble and insoluble. Water-soluble dietary fiber is a type of substance that can both dissolve in water and swell by absorbing water, and can be fermented by microorganisms in the large intestine. After swelling in the gastrointestinal tract, it can form a gel substance with a certain viscosity, making people feel full. It has a good effect on weight control and weight loss for obese people. At the same time, it can delay the emptying time of food in the gastrointestinal tract, slow down the rate of sugar absorption, improve the hunger of diabetic patients, and help stabilize the condition of diabetic patients. Water-soluble dietary fiber can also combine with bile acid and be excreted with feces, preventing bile acid from being reabsorbed in the intestine, thereby lowering serum low-density lipoprotein cholesterol and preventing gallstones. Insoluble dietary fiber refers to the part of dietary fiber that is not digested by human digestive enzymes and is insoluble in water. Although it cannot be digested by enzymes and fermented by microorganisms, it can increase the mass and volume of feces, produce mechanical peristalsis in the intestine, accelerate defecation, reduce the time that harmful substances in feces come into contact with the intestine, and reduce the probability of colorectal cancer. In addition, insoluble dietary fiber can convert NO2 in the stomach into - By reducing the concentration of nitrite to a safe level, it can detoxify patients with early nitrite poisoning and reduce the damage of nitrite to tissues. Compared with insoluble dietary fiber, soluble dietary fiber has stronger physiological effects.

[0004] In recent years, research has explored the use of asparagus in noodle preparation. Yi Jiafeng disclosed "Green Asparagus Fresh Juice Nutritious Noodles and Processing Method Thereof" (CN 101116456 A), which adds asparagus juice to noodles; Li Haiqing et al. disclosed "Asparagus Dietary Fiber Noodles" (CN 106942594 A), which adds 20% asparagus powder to flour; and Wang Hongqi et al. disclosed a method for separating pulp and residue by juicing and applying this to noodle preparation (CN 113951437 A). In these disclosed methods, juicing, crushing, or ultrafine grinding are the primary pretreatment methods for asparagus. The resulting asparagus juice is low in flavonoids, and the residue or crushed asparagus contains low levels of soluble dietary fiber, making it difficult to effectively release flavonoid active substances. The resulting noodles are not significantly different from traditional multi-grain noodles. Summary of the Invention

[0005] In response to the shortcomings of the prior art, the present invention provides a method for preparing noodles rich in flavonoids and soluble dietary fiber by adding asparagus. This method involves juicing fresh, non-commercial asparagus or asparagus byproducts from primary processing, and then enzymatically degrading the high-molecular-weight pectin in the asparagus juice to form more biologically active, low-molecular-weight pectin. Furthermore, the residue is degraded using a combination of reactive oxygen degradation and instantaneous decompression blasting technology, fully releasing the flavonoids from the residue and increasing the soluble dietary fiber content. This is then used to prepare high-quality asparagus noodles, resulting in increased flavonoid and dietary fiber content.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides a method for preparing noodles rich in flavonoids and soluble dietary fiber by adding asparagus, which specifically comprises the following process steps:

[0007] (1) Preparation of enzymatic asparagus juice

[0008] S1 Select fresh non-commercial asparagus or leftovers from primary processing, clean them, remove sand and impurities, and cut them into small pieces for later use;

[0009] S2: The chopped asparagus is treated with superheated steam to inactivate the enzyme, so that the internal temperature reaches 70-90°C and is maintained for 1-3 minutes;

[0010] S3: the asparagus after enzyme inactivation treatment is crushed by a plant tissue crusher, and the crushed asparagus juice is obtained by sieving, and the residue is collected for later use;

[0011] S4: Concentrating the asparagus juice concentrate under low temperature vacuum to reduce its volume to 1 / 3-1 / 5 of the original volume;

[0012] S5 uses pectinase to enzymatically hydrolyze the concentrated asparagus juice. During the enzymatic hydrolysis, 50-200 U of pectinase is added to 100 mL of asparagus concentrate. The enzymatic hydrolysis is carried out for 30-180 minutes at the optimal temperature and pH of the pectinase. After enzymatic hydrolysis, the pectin in the hydrolyzate is mainly small molecular pectin with a molecular weight range of 700-10000 Da.

[0013] The asparagus concentrate after enzymatic hydrolysis in S6 is subjected to enzyme inactivation and other treatments to obtain enzymatic asparagus juice for later use;

[0014] (2) Preparation of asparagus residue by instantaneous decompression blasting

[0015] S1: adjusting the moisture content of the asparagus residue from step (1) S3 to not less than 50%, then placing it in an instantaneous decompression blasting device, and filling it with oxygen to a pressure of 0.5-1.5 MPa;

[0016] The asparagus residue S2 is kept at 150-180°C in an instantaneous decompression blasting device for 30-90 minutes, and then blasted and discharged in a short time through the discharge port of the instantaneous decompression blasting device;

[0017] S3 collects the material discharged from S2 and separates the coarse residue and liquid through screening.

[0018] The S4 liquid is concentrated and spray-dried to dryness; the coarse residue is dried, ultrafinely crushed and sieved, and the two dried products are mixed together to form instantaneous decompression exploded asparagus residue, wherein the asparagus residue has a soluble dietary fiber content of 20-50%;

[0019] (3) Based on 100 parts of high-gluten flour, 20-30 parts of enzymatically hydrolyzed asparagus juice, an appropriate amount of water, 5-15 parts of instantaneous decompression blasted asparagus residue, 2-8 parts of gluten powder, and 0.8-2.0 parts of edible salt are added, and noodles are prepared by conventional calendering method.

[0020] Furthermore, the above-mentioned non-commercial asparagus refers to deformed asparagus, diseased asparagus, and loose asparagus that are not sold on the market.

[0021] Furthermore, the mesh number of S3 in step (1) is 40 meshes; and the mesh number of S4 in step (2) is 200 meshes.

[0022] Furthermore, the water content in step (3) is generally 0-12% of the noodles. Asparagus juice contains a large amount of water, and the amount of water used can be appropriately increased or decreased according to the amount of asparagus juice used.

[0023] Furthermore, the molecular weight of the pectin in the noodles is in the range of 700-10000Da.

[0024] Furthermore, the flavonoid content in the noodles is 2-10 mg / 100 g.

[0025] Furthermore, the soluble dietary fiber content in the noodles is 5-10%.

[0026] Furthermore, the noodle breaking rate during cooking is 0-5%, the water absorption rate during cooking is 200-250%, the tensile strength is 25-35 g, and the stretching distance is 16-22 mm.

[0027] The invention selects fresh non-commercial asparagus or leftovers from primary processing, creatively performs enzyme inactivation treatment, enzymolysis, and extraction to obtain asparagus juice, which is then concentrated and enzymolyzed to obtain enzymatically hydrolyzed asparagus juice. Simultaneously, asparagus residue produced by enzymatic extraction of asparagus residue is subjected to active oxygen degradation combined with instantaneous decompression blasting treatment, spray drying, and ultrafine grinding to obtain instantaneous decompression blasted asparagus residue powder. The asparagus juice is concentrated and enzymolyzed, and the asparagus residue is subjected to active oxygen combined blasting treatment, thereby greatly increasing the content of low-molecular pectin, flavonoids, and soluble dietary fiber, and reducing the content of insoluble dietary fiber. Then, the asparagus juice after the enzymatic hydrolysis treatment and the asparagus residue obtained by the active oxygen combined blasting treatment are used in combination with gluten powder and high-gluten flour to prepare fine noodles, thereby preparing fine noodles rich in flavonoids and soluble dietary fiber with high water absorption rate, low breakage rate, and excellent tensile strength. Generally speaking, the addition of dietary fiber will lead to a loose structure of noodles and a decline in cooking quality. The present invention uses active oxygen degradation combined with blasting treatment to greatly increase the flavonoid content and soluble dietary fiber content in asparagus residue. In addition, by using an appropriate amount of wheat protein, soluble dietary fiber, wheat protein and starch can form a relatively stable structure, so that the noodles prepared by adding asparagus juice and asparagus powder have a high dietary fiber content while also having a cooking quality and texture quality similar to traditional noodles.

[0028] Steam explosion treatment mainly uses the process of placing the raw materials in a high temperature and high pressure environment, filling the pores with steam. When the high pressure is released instantly, the superheated steam in the raw material pores quickly vaporizes, the volume expands rapidly, and the cells "explode". Under the action of mechanical force, the solid material structure is destroyed, and the soluble dietary fiber in the raw material is increased. The present invention uses active oxygen combined with explosion treatment technology to treat asparagus residue. During the heating process, high-purity oxygen is introduced to increase the oxygen content in the explosion equipment. Under high temperature conditions, oxygen will form various active oxygen particles, such as superoxide ion free radicals (O2 - ·), hydroperoxide anion (HOO-), hydroxyl radical (HO·) and peroxide ion (O2 -) These reactive oxygen species can break the chemical bonds between the basic units of lignin and the glycosidic bonds between polysaccharides in the raw material, significantly increasing the soluble dietary fiber and flavonoid content. This also avoids the use of various chemicals, ensuring raw material safety. Compared to conventional explosive treatment, the combined active oxygen explosive treatment increases flavonoid content by approximately 22% and soluble dietary fiber by approximately 29%.

[0029] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0030] (1) The present invention utilizes asparagus primary processing non-commercial asparagus or processing waste as raw materials, and processes asparagus residue through juice extraction, enzymatic hydrolysis, active oxygen degradation combined with instantaneous decompression blasting to realize the food utilization of asparagus processing by-products, thereby reducing resource waste and environmental pollution in asparagus planting and processing; and the treated asparagus juice and asparagus residue are added to flour as raw materials to prepare noodles with high water absorption rate, low breakage rate, excellent tensile strength and rich in flavonoid dietary fiber, thereby increasing the variety of asparagus processed products and noodle products and meeting the market and consumer demand for nutritious and health-care noodle products.

[0031] (2) The present invention uses a concentration process to concentrate and enrich the functional components in asparagus juice. The asparagus juice is enzymatically hydrolyzed using pectinase, degrading large-molecule pectin into small-molecule pectin, thereby enhancing the biological activity of the pectin. Compared with traditional processes, the content of functional components is significantly increased while adding the same amount of asparagus juice. This also avoids production problems caused by excessive asparagus juice, such as overly soft noodles. Furthermore, concentration can increase substrate concentration, reduce enzyme usage during enzymatic hydrolysis, and improve enzymatic hydrolysis efficiency.

[0032] (3) The present invention utilizes active oxygen degradation combined with explosive treatment, utilizing active oxygen to degrade the asparagus residue under high temperature and pressure, followed by instantaneous decompression explosive treatment. This fully releases the flavonoid active substances contained in the asparagus residue while simultaneously increasing the content of soluble dietary fiber. The degradation process does not require the addition of chemicals, thus reducing potential hazards in food processing. Compared to conventional explosive treatment, the active oxygen combined explosive treatment increased the flavonoid content by approximately 22% and the soluble dietary fiber content by approximately 29%. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described below using examples.

[0034] Example 1

[0035] A method for preparing noodles rich in flavonoids and soluble dietary fiber by adding asparagus, specifically comprising the following process steps:

[0036] (1) Preparation of enzymatic asparagus juice

[0037] S1 Select fresh non-commercial asparagus or leftovers from primary processing, wash them with clean water, remove sand and impurities, and cut them into 0.5 cm small segments using a vegetable processor for later use.

[0038] S2: The chopped asparagus was treated with superheated steam to inactivate the enzyme, so that the internal temperature reached 70° C. and maintained for 3 minutes.

[0039] The asparagus after enzyme inactivation treatment in S3 is crushed by a plant tissue crusher, and then passed through a 40-mesh sieve to obtain the asparagus juice concentrate, and the residue is collected for later use.

[0040] S4 performs low-temperature vacuum concentration on the asparagus juice to reduce its volume to 1 / 3 of its original volume.

[0041] S5 used pectinase to enzymatically hydrolyze the concentrated asparagus juice. During the enzymatic hydrolysis, 60 U of pectinase was added to 100 mL of asparagus concentrate, and the enzymatic hydrolysis was carried out for 40 minutes at the optimal temperature and pH of pectinase.

[0042] The asparagus concentrate after S6 enzymatic hydrolysis is subjected to enzyme inactivation and other treatments to obtain enzymatically hydrolyzed asparagus juice, which is then set aside.

[0043] (2) Preparation of asparagus residue by instantaneous decompression blasting

[0044] S1: The asparagus residue from step (1) S3 is adjusted to have a moisture content of not less than 50%, and then placed in an instantaneous decompression blasting device, and oxygen is injected to a pressure of 0.5 MPa.

[0045] The S2 asparagus residue was kept at 160°C for 45 minutes and then discharged through the discharge port of the instantaneous decompression blasting device in a short time.

[0046] S3 collects the discharged material in S2 and separates the coarse residue and liquid through screening.

[0047] The S4 liquid is concentrated and spray-dried to dryness; the coarse residue is dried and ultra-finely pulverized to pass through a 200-mesh screen. The two dried products are mixed together to form instantaneous decompression exploded asparagus residue, which has a soluble dietary fiber content of 26.32%.

[0048] (3) Based on 100 parts of high-gluten flour, 30 parts of enzymatically hydrolyzed asparagus juice, an appropriate amount of water, 5 parts of instantaneous decompression blasted asparagus residue, 3 parts of gluten powder, and 1.5 parts of edible salt were added, and noodles were prepared by conventional calendering method.

[0049] Furthermore, (3) the average molecular weight of pectin in the noodles is 7850Da.

[0050] Furthermore, (3) the flavonoid content in the noodles is 2.32 mg / 100 g.

[0051] Furthermore, (3) the soluble dietary fiber content in the noodles is 5.10%.

[0052] Example 2

[0053] A method for preparing noodles rich in flavonoids and soluble dietary fiber by adding asparagus, specifically comprising the following process steps:

[0054] (1) Preparation of enzymatic asparagus juice

[0055] S1 Select fresh non-commercial asparagus or leftovers from primary processing, wash them with clean water, remove sand and impurities, and cut them into 0.5 cm small segments using a vegetable processor for later use.

[0056] S2: The chopped asparagus is treated with superheated steam to inactivate the enzyme, so that the internal temperature reaches 80°C and is maintained for 2 minutes.

[0057] The asparagus after enzyme inactivation treatment in S3 is crushed by a plant tissue crusher, and then passed through a 40-mesh sieve to obtain the asparagus juice concentrate, and the residue is collected for later use.

[0058] S4 performs low-temperature vacuum concentration on the asparagus juice to reduce its volume to 1 / 5 of its original volume.

[0059] S5 used pectinase to enzymatically hydrolyze the concentrated asparagus juice. During the enzymatic hydrolysis, 200 U of pectinase was added to 100 mL of asparagus concentrate, and the enzymatic hydrolysis was carried out for 160 minutes at the optimal temperature and pH of pectinase.

[0060] The asparagus concentrate after S6 enzymatic hydrolysis is subjected to enzyme inactivation and other treatments to obtain enzymatically hydrolyzed asparagus juice, which is then set aside.

[0061] (2) Preparation of asparagus residue by instantaneous decompression blasting

[0062] S1: The asparagus residue from step (1) S3 is adjusted to have a moisture content of not less than 50%, and then placed in an instantaneous decompression blasting device, and oxygen is injected to a pressure of 1.5 MPa.

[0063] The S2 asparagus residue was kept at 175°C for 80 min and then discharged through the discharge port of the instantaneous decompression blasting device to explode in a short time.

[0064] S3 collects the discharged material from S2 and separates the coarse residue and liquid through screening

[0065] The S4 liquid is concentrated and spray-dried to dryness; the coarse residue is dried and ultra-finely pulverized to pass through a 200-mesh screen. The two dried products are mixed together to form instantaneous decompression exploded asparagus residue, which has a soluble dietary fiber content of 45.89%.

[0066] (3) Based on 100 parts of high-gluten flour, 30 parts of enzymatically hydrolyzed asparagus juice, an appropriate amount of water, 15 parts of instantaneous decompression blasted asparagus residue, 7 parts of gluten, and 2.0 parts of edible salt were added, and noodles were prepared by conventional calendering.

[0067] Furthermore, (3) the average molecular weight of pectin in the noodles is 1600 Da.

[0068] Furthermore, (3) the flavonoid content in the noodles is 9.85 mg / 100 g.

[0069] Furthermore, (3) the soluble dietary fiber content in the noodles is 9.15%.

[0070] Example 3

[0071] A method for preparing noodles rich in flavonoids and soluble dietary fiber by adding asparagus, specifically comprising the following process steps:

[0072] (1) Preparation of enzymatic asparagus juice

[0073] S1 Select fresh non-commercial asparagus or leftovers from primary processing, wash them with clean water, remove sand and impurities, and cut them into 0.5 cm small segments using a vegetable processor for later use.

[0074] S2: The chopped asparagus is treated with superheated steam to inactivate the enzyme, so that the internal temperature reaches 90° C. and is maintained for 2 minutes.

[0075] The asparagus after enzyme inactivation treatment in S3 is crushed by a plant tissue crusher, and then passed through a 40-mesh sieve to obtain the asparagus juice concentrate, and the residue is collected for later use.

[0076] S4 performs low-temperature vacuum concentration on the asparagus juice to reduce its volume to 1 / 4 of its original volume.

[0077] S5 used pectinase to enzymatically hydrolyze the concentrated asparagus juice. During the enzymatic hydrolysis, 100 U of pectinase was added to 100 mL of asparagus concentrate, and the enzymatic hydrolysis was carried out for 120 minutes at the optimal temperature and pH of pectinase.

[0078] The asparagus concentrate after S6 enzymatic hydrolysis is subjected to enzyme inactivation and other treatments to obtain enzymatically hydrolyzed asparagus juice, which is then set aside.

[0079] (2) Preparation of asparagus residue by instantaneous decompression blasting

[0080] S1: The asparagus residue from step (1) S3 is adjusted to have a moisture content of not less than 50%, and then placed in an instantaneous decompression blasting device, and oxygen is injected to a pressure of 1.1 MPa.

[0081] The S2 asparagus residue was kept at 160°C for 50 minutes and then discharged through the discharge port of the instantaneous decompression blasting device in a short time.

[0082] S3 collects the discharged material in S2 and separates the coarse residue and liquid through screening.

[0083] The S4 liquid is concentrated and spray-dried to dryness; the coarse residue is dried and ultra-finely pulverized to pass through a 200-mesh screen. The two dried products are mixed together to form instantaneous decompression exploded asparagus residue, which has a soluble dietary fiber content of 35.45%.

[0084] (3) Based on 100 parts of high-gluten flour, 25 parts of enzymatically hydrolyzed asparagus juice, an appropriate amount of water, 10 parts of instantaneous decompression blasted asparagus residue, 5 parts of gluten, and 1.2 parts of edible salt were added, and noodles were prepared by conventional calendering method.

[0085] Furthermore, (3) the average molecular weight of pectin in the noodles is 4500Da.

[0086] Furthermore, (3) the flavonoid content in the noodles is 4.01 mg / 100 g.

[0087] Furthermore, (3) the soluble dietary fiber content in the noodles is 6.50%.

[0088] Comparative Example

[0089] Comparative Example 1

[0090] After the asparagus juice is squeezed and filtered, the asparagus juice obtained is directly used in the preparation of noodles. The recipe is the same as that of Example 1, except that the instantaneous decompression blasted asparagus residue is replaced with an equal amount of high-gluten flour.

[0091] Comparative Example 2

[0092] The asparagus was dried and then ultra-finely ground for use in the preparation of noodles. The recipe was the same as in Example 2, except that the asparagus juice was replaced with an equal amount of water.

[0093] Comparative Example 3

[0094] After juicing, the juice is directly used in the preparation of noodles without enzymatic hydrolysis and concentration steps. The other steps are the same as those in Example 3.

[0095] Comparative Example 4

[0096] The residue after juicing the asparagus is dried and crushed for use in the preparation of noodles. The other steps are the same as those in Example 3.

[0097] Comparative Example 5

[0098] The noodles are prepared by a conventional process without adding asparagus juice and asparagus residue.

[0099] The noodles obtained in the examples and comparative examples were measured for indicators such as flavonoid content, soluble dietary fiber content (SDF), pectin molecular weight, cooking breakage rate, cooking water absorption rate, tensile strength and tensile distance.

[0100]

[0101]

[0102] The above data demonstrates that enzymatic hydrolysis, concentration, and instantaneous decompression blasting can increase the content of flavonoids and soluble dietary fiber in noodles while reducing the molecular weight of pectin. Furthermore, increasing the soluble dietary fiber content can increase the noodle's water absorption rate during cooking, reduce the breakage rate, and improve the noodles' tensile strength and stretching distance.

Claims

1. A method for preparing noodles rich in flavonoids and soluble dietary fiber by adding asparagus, characterized in that: The specific process steps include the following: (1) Preparation of enzymatic asparagus juice S1 Select fresh non-commercial asparagus or leftovers from primary processing, clean them, remove sand and impurities, and cut them into small pieces for later use; S2: The chopped asparagus is treated with superheated steam to inactivate the enzyme, so that the internal temperature reaches 70-90°C and is maintained for 1-3 minutes; S3: The asparagus after enzyme inactivation is crushed by a plant tissue crusher, and the crushed asparagus juice is obtained by sieving, and the residue is collected for later use; S4: Concentrate the asparagus juice under low-temperature vacuum to reduce its volume to 1 / 3-1 / 5 of its original volume; S5: Enzymatic hydrolysis of concentrated asparagus juice was performed using pectinase. During the hydrolysis, 50-200 U of pectinase was added to 100 mL of asparagus concentrate. The hydrolysis was carried out for 30-180 min at the optimal temperature and pH for pectinase. The pectin in the hydrolyzate was mainly small molecular weight pectin with a molecular weight range of 700-10000 Da. S6 The asparagus concentrate after enzymatic hydrolysis is subjected to enzyme inactivation and other treatments to obtain enzymatic hydrolyzed asparagus juice, which is set aside; (2) Preparation of asparagus residue by instantaneous decompression blasting S1. The asparagus residue from step (1) S3 is adjusted to have a moisture content of not less than 50%, and then placed in an instantaneous decompression blasting device, and oxygen is injected to a pressure of 0.5-1.5 MPa; S2 asparagus residue is kept at 150-180°C for 30-90 minutes in an instantaneous decompression blasting device, and then blasted and discharged in a short time through the discharge port of the instantaneous decompression blasting device; S3 collects the material discharged from S2 and sieves it to separate the coarse residue and liquid; The S4 liquid is concentrated and spray-dried to dryness; the coarse residue is dried, ultrafinely crushed and sieved, and the two dried products are mixed together to form instantaneous decompression explosion asparagus residue, wherein the asparagus residue has a soluble dietary fiber content of 20-50%; (3) Based on 100 parts of high-gluten flour, 20-30 parts of enzymatically hydrolyzed asparagus juice, an appropriate amount of water, 5-15 parts of instantaneous decompression blasted asparagus residue, 2-8 parts of gluten, and 0.8-2.0 parts of edible salt were added, and the noodles were prepared by conventional calendering method. The flavonoid content in the noodles was 2-10 mg / 100 g, and the soluble dietary fiber content was 5-10%.

2. The method according to claim 1, characterized in that The mesh number of S3 in step (1) is 40 mesh; the mesh number of S4 in step (2) is 200 mesh.

3. The method according to claim 1, characterized in that The water content in step (3) is generally 0-12% of the noodles.

4. A noodle rich in flavonoids and soluble dietary fiber prepared by adding asparagus, characterized in that: The raw material composition comprises: taking 100 parts of high-gluten flour as a basis, adding 20-30 parts of enzymatically hydrolyzed asparagus juice, an appropriate amount of water, 5-15 parts of asparagus residue subjected to instantaneous decompression explosion, 2-8 parts of gluten, and 0.8-2.0 parts of edible salt, wherein: the enzymatically hydrolyzed asparagus juice is obtained by chopping asparagus, subjecting it to a hot steam enzyme inactivation treatment, then preparing an asparagus juice stock solution, and then concentrating and enzymolyzing it; the pectin in the enzymatic hydrolyzate after enzymolysis is mainly small molecular pectin with a molecular weight range of 700-10000 Da; the instantaneous decompression explosion asparagus residue is obtained by placing the asparagus residue in an instantaneous decompression explosion device, filling it with oxygen to make its pressure reach 0.5-1.5 MPa; and keeping it warm at 150-180° C. for 30-90 min, and then the asparagus residue is blasted and discharged in a short time through a discharge port of an instantaneous decompression blasting device; the discharged material is sieved to separate coarse residue and liquid, and the liquid is concentrated and spray-dried to dry; the coarse residue is dried, ultrafinely crushed, and sieved, and the two dried materials are mixed to obtain instantaneous decompression blasted asparagus residue, wherein the asparagus residue has a soluble dietary fiber content of 20-50%, and the noodles have a flavonoid content of 2-10 mg / 100 g and a soluble dietary fiber content of 5-10%.

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