Method for preparing fried rice thick slurry through extrusion and enzymolysis

Abstract

The invention discloses a method for preparing fried rice thick slurry through extrusion and enzymolysis, and belongs to the technical field of grain deep processing. The preparation method comprises the following steps: frying rice in advance to increase fragrance and color, and crushing the fried rice and the rice to prepare fried rice noodles and rice noodles; uniformly mixing the fried rice flour and the rice flour according to a certain proportion, and uniformly dispersing one or more enzyme preparations required by enzymolysis in purified water, and reacting and extruding the compound fried rice flour in a twin-screw extruder to obtain extruded enzymolysis fried rice thick slurry, and grinding, centrifuging, homogenizing and sterilizing by using a colloid mill to obtain a final product. The method can be used for efficiently preparing the fried rice thick slurry in a short time, is rapid in enzymolysis, remarkable in liquefaction degree, high in solid content and reducing sugar content and good in stability, and saves the production cost; meanwhile, compared with common thick rice pulp, the color and fragrance of the fried rice are increased, the sensory score is high, the requirement of consumers for the taste of the thick fried rice pulp is met, and the consumer market of the thick fried rice pulp is expanded.

Description

Technical Field

[0001] The invention relates to the technical field of efficient biological conversion in food processing, and in particular to a method for preparing a fried rice slurry by extrusion enzymolysis. Background Art

[0002] Rice, also known as rice, is divided into three types: indica rice, japonica rice and glutinous rice. It is a food made from rice grains after cleaning, husking, milling and finishing. Rice is a global staple food and is often used as an ingredient in puddings, baby food, puffed cereals and breakfast cereals.

[0003] Rice contains about 75% carbohydrates, 7-8% protein, and 1.3-1.8% fat. The linoleic acid content in its fat is relatively high, generally accounting for 34% of all fat. The carbohydrates in rice are mainly starch, and the protein it contains is mainly rice gluten, followed by rice gelatin and globulin. The biological value of its protein and the composition ratio of amino acids are higher than those of cereal crops such as wheat, barley, millet, and corn. The digestibility is 66.8-83.1%, which is also a higher type of cereal protein. Rice also contains a certain amount of dietary fiber, which can promote gastrointestinal motility, promote the digestion and excretion of food in the intestine, and play a positive role in preventing and relieving constipation; it is rich in B vitamins and minerals, including vitamin B1, vitamin B2, vitamin B6 and other vitamins, as well as potassium, phosphorus, magnesium, calcium and other minerals. Therefore, eating rice properly can supplement the vitamins and minerals needed by the body. In recent years, plant-based dairy products are maturing. Compared with milk, rice milk has unique nutritional value and advantages, because it is rich in dietary fiber, B vitamins and minerals, which can not only promote gastrointestinal motility, but also supplement the vitamins and minerals needed by the human body. In addition, rice milk does not contain lactose, which is very friendly to patients with lactose intolerance. Compared with other plant milks such as soy milk, rice has the advantage of not containing soy allergens.

[0004] At present, the enzymatic preparation process of rice milk beverage has certain difficulties. The main reason is that rice starch is easy to age during storage; protein is easy to denature during heat treatment, aggregate to form precipitation, resulting in poor stability. In order to solve the above problems, in the prior art, amylase and the like are usually applied to the preparation of enzymatic rice slurry to degrade starch into dextrin and small molecule sugars to reduce the problems of rough taste and precipitation caused by starch aging. However, the traditional enzymatic hydrolysis conditions are usually strict, and the enzymatic hydrolysis time is lengthy and energy consumption is high; secondly, various stabilizers and thickeners are applied to the preparation of rice slurry, resulting in increased production costs and increased food safety issues. Therefore, as an upstream product of rice milk beverage, it is urgent to optimize and improve the enzymatic hydrolysis process of rice slurry.

[0005] With the relative maturity of extrusion enzymolysis technology, there is an existing technology that uses extrusion enzymolysis to prepare rice beverages. For example, patent (CN 108703284 A) discloses a method for producing non-fermented rice beverages by extrusion enzymolysis liquefaction using high-temperature resistant amylase. Although this method can prepare a rice beverage with relatively stable performance, it has the following problems: first, the rice is not ripened during the pretreatment process, and the rice is simultaneously ripened and liquefied using the extrusion chamber, and the process is short and the enzymolysis and liquefaction are not effectively performed; second, the high-temperature resistant amylase is used to treat rice, and the effect is relatively single. The high-temperature resistant amylase requires a higher temperature to be inactivated, so the enzyme inactivation conditions of the extrusion enzymolysis product are relatively harsh. In addition, the preparation of the rice beverage requires the addition of a stabilizer to obtain a product with relatively stable performance. The addition of the stabilizer will affect the taste of the product, etc., and the preparation cost of the product will also increase. Summary of the invention

[0006] In view of the above-mentioned existing problems, the object of the present invention is to provide a method for preparing a fried rice slurry by extrusion enzymolysis, by combining extrusion technology with enzymolysis technology, and further enzymolyzing the extrusion enzymolysis product to improve the stability, texture and other properties of the fried rice slurry, while improving the content of reducing sugar and sweetness of the product. The present invention adopts fried rice and rice compound as extrusion enzymolysis raw materials, because rice can produce special aroma and flavor after frying, compared with traditional extrusion enzymolysis rice, adding fried rice can increase the aroma and flavor of fried rice of enzymolysis rice dairy products, while changing the color of the product, improving the stability of the product while increasing the content of reducing sugar in the product, improving the sensory score, and expanding the consumer market. The method is energy-efficient, cost-saving, and can be produced continuously.

[0007] In view of the above purpose, the present invention first provides a method for preparing a fried rice slurry by extrusion enzymolysis, comprising the following steps:

[0008] (1) cleaning rice and fried rice and crushing them in a grinder to obtain rice flour and fried rice flour, making 100% of them pass through a 60-mesh sieve, and fully mixing the rice flour and fried rice flour according to a proportion to obtain composite fried rice flour;

[0009] (2) dispersing the enzyme preparation in purified water to prepare an enzymatic solution;

[0010] (3) placing the composite fried rice noodles obtained in step (1) and the enzymatic hydrolyzate obtained in step (2) in the barrel of a twin-screw extruder respectively, and performing reaction extrusion in the twin-screw extruder to obtain an extruded enzymatically hydrolyzed fried rice concentrated slurry;

[0011] (4) adding saccharifying enzyme to the extruded enzymatically hydrolyzed fried rice slurry obtained in step (3), mixing well and evenly, reacting and hydrolyzing, and obtaining a new enzymatically hydrolyzed fried rice slurry;

[0012] (5) grinding the newly enzymatically hydrolyzed fried rice slurry obtained in step (4) using a colloid mill;

[0013] (6) separating the residue from the product obtained in step (5) by horizontal screw centrifugation and homogenizing the obtained product;

[0014] (7) sterilizing and filling the product obtained in step (6) to obtain a finished product of enzymatically hydrolyzed fried rice slurry.

[0015] In one embodiment of the present invention, the mixing mass ratio of rice noodles to fried rice noodles in step (1) is 7:3 to 8:2.

[0016] In one embodiment of the present invention, the enzyme preparation in step (2) comprises one or a mixture of any proportion of medium-temperature α-amylase, high-temperature α-amylase and saccharifying enzyme, and the added amount of the enzyme preparation is 1 to 10‰ of the mass of the compound fried rice noodles.

[0017] In one embodiment of the present invention, the extrusion temperature in step (3) is 60-120° C., the feeding rate is 3-20 kg / h, the liquid feeding rate is 5-35 L / h, the screw speed is 100-300 r / min, and the water content of the extruded material is 50-70%.

[0018] In one embodiment of the present invention, the amount of saccharifying enzyme added in step (4) is 0.1 to 2‰ of the solid content in the extruded enzymatically hydrolyzed fried rice slurry.

[0019] In one embodiment of the present invention, in step (5), the grinding fineness of the colloid mill is 200-300 mesh, and the grinding time is 0.5-5 min.

[0020] In one embodiment of the present invention, the centrifugal process in step (6) has a rotation speed of 2000-3000 r / min and a centrifugal time of 1-5 min.

[0021] In one embodiment of the present invention, the homogenization pressure in step (6) is 30-60 MPa, and the homogenization times are 1-2 times.

[0022] In one embodiment of the present invention, the sterilization conditions in step (7) are: sterilization temperature 105-135° C., sterilization time 15-60 s.

[0023] The invention also provides an enzymatically hydrolyzed fried rice concentrated slurry prepared according to the method.

[0024] Beneficial effects of the present invention:

[0025] (1) The present invention combines extrusion technology with enzymolysis technology to form an extrusion enzymolysis processing method. Extrusion is a high-temperature, short-time, continuous and multifunctional thermomechanical technology. It integrates multiple operating units such as material mixing, stirring, shearing, heating, cooking, and molding, and can achieve sustained high productivity. Extrusion enzymolysis is to use the extruder as an enzyme-catalyzed bioreactor, and introduce exogenous enzyme preparations to assist extrusion during the extrusion process to enhance the effect on the substrate. During the extrusion enzymolysis process, the enzyme acts on the substrate in a radial path from the center to the outside, and mechanical effects such as screw shearing and pressure will induce enzyme activation and show high efficiency and activity. It saves time and effort, saves energy, and can be produced continuously. The finished fried rice slurry has good stability and good taste. As a new type of extrusion enzymolysis product, it fills the market gap and provides a new choice for plant-based dairy products.

[0026] (2) The present invention uses fried rice and rice compound as extrusion enzymatic hydrolysis raw materials, because fried rice can produce special aroma and flavor. Compared with traditional extruded enzymatic hydrolysis rice, adding fried rice can increase the fried rice aroma and flavor of enzymatic hydrolyzed rice dairy products, while changing the product color, improving the sensory score, and expanding the consumer market.

[0027] (3) By using different types of enzyme preparations for compounding and applying the compound enzymatic hydrolysate to the extrusion enzymatic hydrolysis of fried rice and rice mixture, the composite enzymatic hydrolysis can significantly improve the stability and sensory properties of the fried rice concentrate. At the same time, the composite enzymatic hydrolysis can also significantly increase the content of reducing sugars in the concentrate and improve the sweetness of the concentrate. Enterprises can use the sweetness of the concentrate itself without adding exogenous industrial syrup to produce rice milk products.

[0028] (4) Adding saccharifying enzyme to the fried rice slurry obtained after extrusion enzymatic hydrolysis, and using the residual temperature of the slurry after extrusion to continue enzymatic hydrolysis and liquefaction, while maintaining the total amount of enzyme preparation unchanged, can not only significantly increase the content of reducing sugar in the product, but also reduce the cost of enzyme preparation, and significantly improve the stability, appearance, texture and taste of the extruded enzymatic hydrolysis product. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is the reducing sugar standard curve;

[0030] Figure 2 The scoring rules for sensory evaluation of fried rice paste;

[0031] Figure 3 It is a schematic diagram of the process flow of the present invention. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present invention will be described in a complete and clear manner below. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them.

[0033] The enzyme preparations used in the examples of the present invention were purchased from Beijing Novozymes Co., Ltd., wherein the activity of the medium-temperature α-amylase was 480 KNU / g, the activity of the high-temperature α-amylase was 120 KUN / mL, and the activity of the saccharifying enzyme was 300 AGU / g.

[0034] Test method:

[0035] Solid content: The solid content of the extruded enzymatic hydrolyzed samples was determined using the oven method.

[0036] Reducing sugar content:

[0037] First, prepare a glucose standard solution with a concentration of 1 mg / mL. Take 0, 0.2, 0.4, 0.6, 0.8, and 1.0 mL of the glucose standard solution in a centrifuge tube, add deionized water to 1.0 mL, accurately add 1.5 mL of DNS color developer, heat in a boiling water bath for 5 min, and then quickly cool to room temperature. Accurately add 1.5 mL of deionized water to dilute and mix, measure the absorbance at a wavelength of 540 nm, and draw a standard curve, such as Figure 1 As shown;

[0038] Secondly, take 1.0g sample, add appropriate amount of deionized water, vortex for 1min, centrifuge at 8000g for 10min, and take the supernatant; add appropriate amount of deionized water to the sediment again, centrifuge at 8000g for 10min, combine the two supernatants, and make up to volume in a 100mL volumetric flask for later use. Take 200μL of diluted supernatant in a 2ml centrifuge tube, add 200μL of deionized water and 300μL of DNS colorimetric agent, boil in water bath for 5min and quickly cool to room temperature, add 300μL of deionized water again to dilute and mix, take an appropriate amount and color at 540nm wavelength of the microplate reader, and read the absorbance; finally, use the standard curve to calculate the reducing sugar content of the sample.

[0039] DE value: The percentage of reducing sugar content (calculated as glucose) in the sample to dry matter is called DE value, and the formula is as follows:

[0040] DE value = (reducing sugar content%) / (dry matter content%) x 100%

[0041] Sensory evaluation: 50 people were randomly selected as test volunteers, and the appearance, flavor, taste, etc. of the extruded enzymatically hydrolyzed fried rice slurry of Examples 1 to 5 were evaluated, with a full score of 100. A total of 49 valid results were collected, and the specific evaluation method is shown in Figure 2 .

[0042] Except for sensory evaluation, all experiments were repeated three times, and the results were expressed as mean ± standard deviation. SPSS25.0 software was used to analyze the data with one-way analysis of variance and Duncan test, and p < 0.05 was considered statistically significant.

[0043] Example 1

[0044] A method for preparing a fried rice slurry by extrusion enzymolysis comprises the following steps:

[0045] (1) cleaning the rice and the fried rice and crushing them in a grinder so that 100% of the particles pass through a 60-mesh sieve to obtain rice noodles and fried rice noodles;

[0046] (2) mixing the rice noodles and the fried rice noodles evenly in a ratio of 7:3 to form composite fried rice noodles;

[0047] (3) evenly dispersing 5‰ of the mass of the composite fried rice noodles with a medium-temperature α-amylase in purified water to form an enzymatic hydrolyzate;

[0048] (4) placing the composite fried rice noodles and the enzymolysis solution in the barrel of a twin-screw extruder respectively, and reacting and extruding in the twin-screw extruder, wherein the temperatures in the six temperature zones of the extruder are 65° C., 70° C., 75° C., 80° C., 85° C., and 95° C., respectively, the feeding rate is 5 kg / h, the screw speed is 150 r / min, and the liquid feed rate is 8 L / h, to obtain an enzymolysis fried rice slurry;

[0049] (5) grinding the enzymatically hydrolyzed fried rice slurry using a colloid mill with a grinding fineness of 290 mesh and a grinding time of 1 min;

[0050] (6) centrifuging the ground fried rice slurry at 2800 r / min for 3 min using a horizontal screw centrifuge;

[0051] (7) homogenizing the centrifugally separated fried rice slurry at 40 MPa for one time;

[0052] (8) sterilizing the homogenized fried rice slurry at a temperature of 115° C. for 60 seconds, and aseptically cold filling the sterilized fried rice slurry to obtain a finished fried rice slurry.

[0053] Example 2

[0054] A method for preparing a fried rice slurry by extrusion enzymolysis comprises the following steps:

[0055] (1) cleaning the rice and the fried rice and crushing them in a grinder so that 100% of the particles pass through a 60-mesh sieve to obtain rice noodles and fried rice noodles;

[0056] (2) mixing the rice noodles and the fried rice noodles evenly in a ratio of 7:3 to form composite fried rice noodles;

[0057] (3) uniformly dispersing 2‰ of the mass of medium-temperature α-amylase and 3‰ of the mass of high-temperature α-amylase in purified water to form an enzymatic solution;

[0058] (4) placing the composite fried rice flour and the enzymolysis solution in the barrel of a twin-screw extruder respectively, and reacting and extruding in the twin-screw extruder, wherein the temperatures of the six temperature zones of the extruder are respectively 70° C., 80° C., 85° C., 95° C., 105° C., and 115° C., the feeding rate is 5 kg / h, the screw speed is 150 r / min, and the liquid feed rate is 8 L / h, to obtain an enzymolysis fried rice slurry;

[0059] (5) grinding the enzymatically hydrolyzed fried rice slurry using a colloid mill with a grinding fineness of 290 mesh and a grinding time of 1 min;

[0060] (6) centrifuging the ground fried rice slurry at 2800 r / min for 3 min using a horizontal screw centrifuge;

[0061] (7) homogenizing the centrifugally separated fried rice slurry at 40 MPa for one time;

[0062] (8) sterilizing the homogenized fried rice slurry at a temperature of 115° C. for 60 seconds, and aseptically cold filling the sterilized fried rice slurry to obtain a finished fried rice slurry.

[0063] Example 3

[0064] A method for preparing a fried rice slurry by extrusion enzymolysis comprises the following steps:

[0065] (1) cleaning the rice and the fried rice and crushing them in a grinder so that 100% of the particles pass through a 60-mesh sieve to obtain rice noodles and fried rice noodles;

[0066] (2) mixing the rice noodles and the fried rice noodles evenly in a ratio of 7:3 to form composite fried rice noodles;

[0067] (3) uniformly dispersing 2‰ of the mass of medium-temperature α-amylase, 2‰ of high-temperature α-amylase and 1‰ of saccharifying enzyme in purified water to form an enzymatic solution;

[0068] (4) placing the composite fried rice noodles and the enzymolysis solution in the barrel of a twin-screw extruder respectively, and reacting and extruding in the twin-screw extruder, wherein the temperatures of the six temperature zones of the extruder are respectively 65° C., 70° C., 75° C., 85° C., 95° C., and 105° C., the feeding rate is 5 kg / h, the screw speed is 150 r / min, and the liquid feed rate is 8 L / h, to obtain an enzymolysis fried rice slurry;

[0069] (5) grinding the enzymatically hydrolyzed fried rice slurry using a colloid mill with a grinding fineness of 290 mesh and a grinding time of 1 min;

[0070] (6) centrifuging the ground fried rice slurry at 2800 r / min for 3 min using a horizontal screw centrifuge;

[0071] (7) homogenizing the centrifugally separated fried rice slurry at 40 MPa for one time;

[0072] (8) sterilizing the homogenized fried rice slurry at a temperature of 115° C. for 60 seconds, and aseptically cold filling the sterilized fried rice slurry to obtain a finished fried rice slurry.

[0073] Example 4

[0074] A method for preparing a fried rice slurry by extrusion enzymolysis comprises the following steps:

[0075] (1) cleaning the rice and the fried rice and crushing them in a grinder so that 100% of the particles pass through a 60-mesh sieve to obtain rice noodles and fried rice noodles;

[0076] (2) mixing the rice noodles and the fried rice noodles evenly in a ratio of 7:3 to form composite fried rice noodles;

[0077] (3) evenly dispersing 1‰ of the mass of the composite fried rice noodles with a medium-temperature α-amylase and 3‰ of the mass of the high-temperature α-amylase in purified water to form an enzymatic solution;

[0078] (4) placing the composite fried rice flour and the enzymolysis solution in the barrel of a twin-screw extruder respectively, and reacting and extruding in the twin-screw extruder, wherein the temperatures of the six temperature zones of the extruder are respectively 70° C., 80° C., 85° C., 95° C., 105° C., and 115° C., the feeding rate is 5 kg / h, the screw speed is 150 r / min, and the liquid feed rate is 8 L / h, to obtain an enzymolysis fried rice slurry;

[0079] (5) grinding the enzymatically hydrolyzed fried rice slurry using a colloid mill with a grinding fineness of 290 mesh and a grinding time of 1 min;

[0080] (6) centrifuging the ground fried rice slurry at 2800 r / min for 3 min using a horizontal screw centrifuge;

[0081] (7) homogenizing the centrifugally separated fried rice slurry at 40 MPa for one time;

[0082] (8) sterilizing the homogenized fried rice slurry at a temperature of 115° C. for 60 seconds, and aseptically cold filling the sterilized fried rice slurry to obtain a finished fried rice slurry.

[0083] Example 5

[0084] A method for preparing a fried rice slurry by extrusion enzymolysis comprises the following steps:

[0085] (1) cleaning the rice and the fried rice and crushing them in a grinder so that 100% of the particles pass through a 60-mesh sieve to obtain rice noodles and fried rice noodles;

[0086] (2) mixing the rice noodles and the fried rice noodles evenly in a ratio of 7:3 to form composite fried rice noodles;

[0087] (3) evenly dispersing 1‰ of the mass of the composite fried rice noodles with a medium-temperature α-amylase and 3‰ of the mass of the high-temperature α-amylase in purified water to form an enzymatic solution;

[0088] (4) placing the composite fried rice flour and the enzymolysis solution in the barrel of a twin-screw extruder respectively, and reacting and extruding in the twin-screw extruder, wherein the temperatures of the six temperature zones of the extruder are respectively 70° C., 80° C., 85° C., 95° C., 105° C., and 115° C., the feeding rate is 5 kg / h, the screw speed is 150 r / min, and the liquid feed rate is 8 L / h, to obtain an enzymolysis fried rice slurry;

[0089] (5) adding 1‰ saccharifying enzyme to the enzymolysis fried rice slurry according to its solid content, mixing well and allowing enzymolysis to react, thereby obtaining a new enzymolysis fried rice slurry;

[0090] (6) grinding the newly enzymatically hydrolyzed fried rice slurry using a colloid mill with a grinding fineness of 290 mesh and a grinding time of 1 min;

[0091] (7) centrifuging the ground fried rice slurry at 2800 r / min for 3 min using a horizontal screw centrifuge;

[0092] (8) homogenizing the centrifugally separated fried rice slurry at 40 MPa for one time;

[0093] (9) sterilizing the homogenized fried rice slurry at a temperature of 115° C. for 60 seconds, and aseptically cold filling the sterilized fried rice slurry to obtain a finished fried rice slurry.

[0094] The solid content, reducing sugar content, DE value, etc. of the fried rice slurries obtained in Examples 1 to 5 were measured. The results are shown in Table 1. The sensory evaluation statistical score results are shown in Table 2.

[0095] Table 1. Solids, reducing sugar content and DE value of fried rice slurry hydrolyzed by extrusion with different enzyme preparations

[0096]

[0097] Table 2. Sensory evaluation score table of fried rice paste

[0098]

[0099]

[0100] It can be seen from the test results of Examples 1 to 5 that the stability, reducing sugar content and DE value of the concentrated slurry after enzymatic hydrolysis by a single enzyme preparation are improved, and the retrogradation of rice starch is inhibited; the enzymatic hydrolysis effect of the composite enzyme preparation is better, the liquefaction degree is higher, and the stability of the concentrated slurry is improved. The use of medium-temperature α-amylase can reduce the temperature of the extrusion cavity on the basis of ensuring the enzymatic hydrolysis effect, and at the same time, the temperature at the end of the cavity is used to inactivate the medium-temperature α-amylase, which saves energy and increases efficiency; the composite enzyme formed by the medium-temperature α-amylase and the high-temperature α-amylase can better liquefy rice starch to form dextrin or small molecule sugars, and significantly increase the reducing sugar content of the concentrated slurry; it can be seen from the data in the table that due to the different action temperatures of the three enzymes, composite extrusion cannot achieve the best effect. On the contrary, the composite fried rice noodles are first extruded and hydrolyzed using a composite enzyme formed by medium-temperature α-amylase and high-temperature α-amylase, and then exogenous saccharifying enzyme is added to the slurry formed after extrusion, and the residual temperature of the slurry is used to continue enzymatic hydrolysis and liquefaction. This is more conducive to improving the performance of the fried rice slurry. The fried rice slurry has better stability, higher liquefaction degree, significantly increased sweetness, and a delicate taste, while retaining the original aroma of the fried rice.

[0101] Compared with the traditional enzymatic hydrolysis method, the extrusion enzymatic hydrolysis production method can significantly improve the stability and sensory score of the fried rice slurry; changing the type and amount of the corresponding enzyme preparation has a positive effect on the stability and sensory score of the fried rice slurry. At the same time, extrusion enzymatic hydrolysis can save enzymatic hydrolysis time and reduce energy consumption, and reduce the addition of various stabilizers and thickeners; it can reduce costs for enterprises and provide consumers with a new type of safe, nutritious and healthy plant-based beverage.

[0102] The embodiments provided above are not intended to limit the scope of the present invention, and the steps described are not intended to limit the execution order thereof. Those skilled in the art may make obvious improvements to the present invention in combination with existing common knowledge, which also fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for preparing a fried rice concentrate by extrusion enzymolysis, characterized in that: The following steps are involved: (1) cleaning rice and fried rice and crushing them in a grinder to obtain rice flour and fried rice flour, making 100% of them pass through a 60-mesh sieve, and fully mixing the rice flour and fried rice flour according to a proportion to obtain composite fried rice flour; (2) dispersing the enzyme preparation in purified water to prepare an enzymatic solution; (3) placing the composite fried rice noodles obtained in step (1) and the enzymatic hydrolyzate obtained in step (2) in a silo of a twin-screw extruder respectively, and performing reaction extrusion in the twin-screw extruder to obtain an extruded enzymatically hydrolyzed fried rice concentrated slurry; (4) adding saccharifying enzyme to the extruded enzymatically hydrolyzed fried rice slurry obtained in step (3), mixing well and evenly, reacting and hydrolyzing, and obtaining a new enzymatically hydrolyzed fried rice slurry; (5) grinding the newly enzymatically hydrolyzed fried rice slurry obtained in step (4) using a colloid mill; (6) separating the residue from the product obtained in step (5) by horizontal screw centrifugation and homogenizing the obtained product; (7) sterilizing and filling the product obtained in step (6) to obtain a finished product of enzymatically hydrolyzed fried rice slurry.

2. The method according to claim 1, characterized in that In step (1), the mixed compounding mass ratio of rice noodles to fried rice noodles is 7:3 to 8:

2.

3. The method according to claim 1, characterized in that The enzyme preparation in step (2) comprises one or a mixture of any proportion of medium-temperature α-amylase, high-temperature α-amylase and saccharifying enzyme, and the added amount of the enzyme preparation is 1 to 10‰ of the mass of the composite fried rice noodles.

4. The method according to claim 1, characterized in that: The extrusion temperature in step (3) is 60-120° C., the feeding rate is 3-20 kg / h, the liquid feeding rate is 5-35 L / h, the screw speed is 100-300 r / min, and the water content of the extruded material is 50-70%.

5. The method according to claim 1, characterized in that The amount of saccharifying enzyme added in step (4) is 0.1 to 2‰ of the solid content in the extruded enzymatically hydrolyzed fried rice slurry.

6. The method according to claim 1, characterized in that In step (5), the colloid mill has a grinding fineness of 200 to 300 meshes and a grinding time of 0.5 to 5 min.

7. The method according to claim 1, characterized in that In step (6), the centrifugal process speed is 2000-3000 r / min, and the centrifugal time is 1-5 min.

8. The method according to claim 1, characterized in that In step (6), the homogenization pressure is 30-60 MPa, and the homogenization times are 1-2 times.

9. The method according to claim 1, characterized in that: The sterilization conditions in step (7) are: sterilization temperature 105-135°C, sterilization time 15-60s.

10. The enzymatically hydrolyzed fried rice concentrate prepared by the method according to any one of claims 1 to 9.

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