Preparation method of rice noodles and application of rice noodles in instant food

Abstract

The invention relates to the field of food, in particular to a preparation method of rice noodles and application of the rice noodles in instant food. Indica rice flour and glutinous rice flour are used as raw materials, an aqueous solution containing functional raw materials is added, the mixture is stirred and then kneaded into dough, and the dough is extruded in an extruder, cut, cured in a constant-temperature room and freeze-dried to prepare the rice noodles. The rice noodles are prepared by combining the long-shaped rice and the glutinous rice, so that the rice noodles are more comprehensive in nutrition and have the comprehensive effects of excellent color, moderate hardness, no sticking to teeth and strong rice fragrance; meanwhile, the functional raw materials are obtained by extracting dried tangerine peels and dried mulberries, so that the rice noodles are endowed with an excellent digestion aiding effect.

Description

Technical Field

[0001] The invention relates to the field of food, and in particular to a method for preparing rice noodles and application of the rice noodles in instant food. Background Art

[0002] Rice noodles, also known as rice noodles, rice shreds or rice noodles, are long strips of rice food, usually round in cross section, white in color and tough. According to the production method and regional characteristics, rice noodles can be classified into many categories, such as Physalis rice noodles, dry rice noodles, etc.

[0003] The basic raw material for making rice noodles is rice, including indica rice, japonica rice and glutinous rice. Indica rice is rich in protein, fat, riboflavin, niacin, various minerals and a small amount of carbohydrates. Indica rice has the effects of invigorating qi, nourishing yin, moistening dryness, nourishing qi and nourishing the heart, nourishing the liver and nourishing the body, strengthening the essence and will, harmonizing the five internal organs, unblocking blood vessels, improving hearing and eyesight, relieving restlessness, quenching thirst and stopping diarrhea. Japonica rice is an important rice variety. The rice grains obtained by shelling the seeds of japonica rice are short and wide in appearance, crystal clear, hard in texture, soft in taste after cooking, and less sticky; it is not only one of the staple foods in people's daily diet, but also often used to make various traditional delicacies, such as sushi, rice dumplings, porridge, etc. Glutinous rice has excellent nutritional and health effects. It is a mild tonic that has the effects of replenishing deficiency, replenishing blood, strengthening the spleen and warming the stomach, and stopping sweating; Glutinous rice contains protein, fat, sugar, calcium, phosphorus, iron, vitamin B and starch, etc., which is a warming and strengthening product.

[0004] Rice noodles made from indica rice have a single nutritional value, a hard texture, and a poor taste; rice noodles made from glutinous rice have a good nutritional value, but are too soft and difficult to digest. Therefore, providing a rice noodle containing indica rice and glutinous rice to overcome the defects of the rice noodle having an inappropriate hardness and softness, a single nutritional value, insufficient health effects, and being difficult to digest is a topic that needs to be studied at present. Summary of the invention

[0005] The present invention aims at the above technical problems and proposes a technical solution of the present invention. The technical solution of the present invention includes a preparation method of rice noodles and application of the rice noodles in instant foods.

[0006] One aspect of the present invention provides a method for preparing rice noodles, comprising the following steps:

[0007] Step 1: Grind and sieve indica rice and glutinous rice separately to obtain indica rice flour and glutinous rice flour;

[0008] Step 2: Mix indica rice flour and glutinous rice flour according to weight to obtain a mixed powder, and mix the functional raw material with water to obtain a solution;

[0009] Step 3: Add the mixed solution to the mixed powder, stir and knead into dough;

[0010] Step 4: placing the dough in an extruder for extrusion, and then cutting it to obtain a crude rice noodle product;

[0011] Step 5: The crude rice noodles are matured in a constant temperature chamber and freeze-dried to obtain the rice noodles.

[0012] Preferably, the mesh size of the sieve used for screening is greater than 50 meshes.

[0013] Preferably, in step 2, the raw materials used are in the following amounts, by weight: 100-150 parts of indica rice flour, 10-25 parts of glutinous rice flour, 0.1-1 parts of functional raw materials and 50-80 parts of water.

[0014] Preferably, the diameter of the thick rice noodles is 0.5-2 mm.

[0015] Preferably, the length of the crude rice noodles is not limited to 10-30 cm.

[0016] Preferably, water vapor at 110-130° C. is introduced into the constant temperature chamber to ripen the crude rice noodles.

[0017] Preferably, the aging time is 6-10 minutes.

[0018] Another aspect of the present invention provides rice noodles prepared using the above preparation method.

[0019] Another aspect of the present invention provides use of the rice noodles in preparing instant food.

[0020] Another aspect of the present invention provides a method for preparing an extract of dried tangerine peel and dried mulberries, comprising the following steps:

[0021] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of tangerine peel to mulberries of 1:0.8-1.2 to obtain a mixture, add 0.5-1.5 times the mass of the mixture of water, beat, and then add 10-40 times the mass of the mixture of water to mix, to obtain product S1;

[0022] S2: Add trypsin in an amount of 200-400 u / g of product S1 to product S1, perform enzymolysis at 40-50° C. for 2-4 hours, inactivate the enzyme, and obtain product S2;

[0023] S3: Add 0.5-3% glucose and 0.001-0.05% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 7.5×10 9 -2.7×10 10 cfu / g pre-fermented material is inoculated with fermentation bacteria, wherein the fermentation bacteria are composed of Lactobacillus fermentum 1.1796 and Lactobacillus acidophilus 1.1807 in a quantity ratio of 2-3.5:1, and the fermentation is stirred at 25-40°C for 70-140 hours, sterilized, and a product S3 is obtained;

[0024] S4: Filter the product S3 and dry it to obtain the extract.

[0025] Preferably, the extracts of dried tangerine peel and dried mulberry can be used as the functional raw materials mentioned above.

[0026] Preferably, the extracts of dried tangerine peel and dried mulberry are used as functional raw materials for preparing rice noodles.

[0027] Beneficial effects of the present invention:

[0028] The invention adopts indica rice and glutinous rice flour as raw materials, adds an aqueous solution containing functional raw materials, stirs and then kneads into dough, extrude in an extruder, cuts, matures in a constant temperature chamber, freeze-dries, and prepares rice noodles; the indica rice and glutinous rice are combined to make the rice noodles more comprehensive in nutrition, and have the comprehensive effects of excellent color, moderate hardness, no stickiness to teeth, and strong rice flavor; meanwhile, the functional raw materials are extracted from tangerine peel and dried mulberry, and thus give the rice noodles excellent digestion-aiding effect.

[0029] The extract prepared by the invention can effectively aid digestion and impart a better effect to the rice noodles.

[0030] The use of trypsin in the extract of the present invention can greatly enhance the digestive effect of the extract.

[0031] The present invention adopts dried tangerine peel and dried mulberry for extraction, which can enrich the types and richness of digestive active ingredients in the extract, produce a complementary effect, and promote each other to enhance the digestive effect.

[0032] Compared with other bacteria, the present invention adopts Lactobacillus fermentum 1.1796 and Lactobacillus acidophilus 1.1807 for fermentation, which can further enhance the digestion-aiding effect of the extract.

[0033] The present invention adopts Lactobacillus fermentum 1.1796 and Lactobacillus acidophilus 1.1807 for joint fermentation, which can synergistically improve the digestion-aiding ability of the extract, making the rice noodles more acceptable and edible to different groups of people. When Lactobacillus fermentum 1.1796 and Lactobacillus acidophilus 1.1807 are fermented in a quantity ratio of 2-3.5:1 during the fermentation and extraction process, the effect of the prepared extract is better.

[0034] The extract of the invention can effectively improve the digestibility of rice noodles, so that people who eat them can better digest them after eating a large amount of them, and can also be eaten by people with insufficient digestive ability.

[0035] The addition of glutinous rice to the rice noodles of the present invention can increase the rice aroma of the rice noodles and reduce the defect of the rice noodles being too hard. When a large amount of glutinous rice is used in the rice noodles, although the aroma can be increased, the color is reduced to a certain extent, and the hardness and viscosity are reduced, which will also greatly affect the digestibility of the rice noodles.

[0036] The rice noodle preparation process is simple, the rice noodle has excellent functions and has good application prospects. DETAILED DESCRIPTION

[0037] The present invention will be described below in conjunction with specific embodiments, and various effects of the present invention will be more clearly presented. It should be understood by those skilled in the art that these specific embodiments are used to illustrate the present invention, rather than to limit the present invention.

[0038] Trypsin: Product No. S10032, 250u / mg, Shanghai Yuanye Biotechnology.

[0039] Papain: Product No. S10011, 800u / mg, Shanghai Yuanye Biotechnology.

[0040] Lactobacillus fermentum 1.1796: strain number: GDMCC NO.: 1.1796, purchased from Guangdong Provincial Microbiological Culture Collection Center.

[0041] Lactobacillus acidophilus 1.1807: strain number: GDMCC NO.: 1.1807, purchased from Guangdong Microbiological Culture Collection Center.

[0042] Lactobacillus plantarum CICC 20717: strain number: CICC 20717, purchased from China Industrial Microbiology Culture Collection Administration Center.

[0043] 1. Extracts

[0044] Extract 1:

[0045] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:1 to obtain a mixture, add 1 times the mass of water of the mixture, beat, then add 20 times the mass of water of the mixture, mix, and obtain product S1;

[0046] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0047] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria consisted of Lactobacillus fermentans 1.1796 and Lactobacillus acidophilus 1.1807 in a quantity ratio of 3:1, and anaerobically fermented at 35°C and 60rpm for 125 hours, and sterilized to obtain product S3;

[0048] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0049] Extract 2:

[0050] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:0.8 to obtain a mixture, add 1.1 times the mass of the mixture of water, beat, then add 22 times the mass of the mixture of water, mix, and obtain product S1;

[0051] S2: Add 280u / g trypsin to product S1, stir at 48°C and 60rpm for 4 hours, inactivate the enzyme, and obtain product S2;

[0052] S3: Add 2.3% glucose and 0.027% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.15×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria consisted of Lactobacillus fermentans 1.1796 and Lactobacillus acidophilus 1.1807 in a quantity ratio of 2:1, and anaerobically fermented at 37°C and 60rpm for 140 hours, and sterilized to obtain product S3;

[0053] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -35°C to a water content of 1.49 wt%, to obtain the extract.

[0054] Extract 3:

[0055] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:1 to obtain a mixture, add 1 times the mass of water of the mixture, beat, then add 20 times the mass of water of the mixture, mix, and obtain product S1;

[0056] S2: Add 300u / g of papain to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0057] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria consisted of Lactobacillus fermentans 1.1796 and Lactobacillus acidophilus 1.1807 in a quantity ratio of 3:1, and anaerobically fermented at 35°C and 60rpm for 125 hours, and sterilized to obtain product S3;

[0058] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0059] Extract 4:

[0060] S1: Wash and drain the dried tangerine peel to obtain a drained material, add 1 times the mass of the drained material with water, beat, then add 20 times the mass of the drained material with water, mix, and obtain product S1;

[0061] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0062] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria consisted of Lactobacillus fermentans 1.1796 and Lactobacillus acidophilus 1.1807 in a quantity ratio of 3:1, and anaerobically fermented at 35°C and 60rpm for 125 hours, and sterilized to obtain product S3;

[0063] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0064] Extract 5:

[0065] S1: Wash and drain the dried mulberries to obtain a drained material, add 1 times the mass of water to the drained material, beat, then add 20 times the mass of water to the drained material, mix, and obtain product S1;

[0066] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0067] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria consisted of Lactobacillus fermentans 1.1796 and Lactobacillus acidophilus 1.1807 in a quantity ratio of 3:1, and anaerobically fermented at 35°C and 60rpm for 125 hours, and sterilized to obtain product S3;

[0068] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0069] Extract 6:

[0070] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:1 to obtain a mixture, add 1 times the mass of water of the mixture, beat, then add 20 times the mass of water of the mixture, mix, and obtain product S1;

[0071] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0072] S3: The product S2 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0073] Extract 7:

[0074] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:1 to obtain a mixture, add 1 times the mass of water of the mixture, beat, then add 20 times the mass of water of the mixture, mix, and obtain product S1;

[0075] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0076] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria was Lactobacillus fermentum 1.1796, and anaerobically fermented at 35°C and 60rpm for 125 hours, and sterilized to obtain product S3;

[0077] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0078] Extract 8:

[0079] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:1 to obtain a mixture, add 1 times the mass of water of the mixture, beat, then add 20 times the mass of water of the mixture, mix, and obtain product S1;

[0080] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0081] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria was Lactobacillus acidophilus 1.1807, and anaerobically fermented at 35°C and 60rpm for 125 hours, and sterilized to obtain product S3;

[0082] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0083] Extract 9:

[0084] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:1 to obtain a mixture, add 1 times the mass of water of the mixture, beat, then add 20 times the mass of water of the mixture, mix, and obtain product S1;

[0085] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0086] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria consisted of Lactobacillus fermentum 1.1796 and Lactobacillus acidophilus 1.1807 in a quantitative ratio of 0.5:1, and anaerobically fermented at 35°C and 60rpm for 125 hours, and sterilized to obtain product S3;

[0087] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0088] Extract 10:

[0089] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:1 to obtain a mixture, add 1 times the mass of water of the mixture, beat, then add 20 times the mass of water of the mixture, mix, and obtain product S1;

[0090] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0091] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermented material was inoculated with fermentation bacteria, the fermentation bacteria consisted of Lactobacillus fermentum 1.1796 and Lactobacillus acidophilus 1.1807 in a quantitative ratio of 7.5:1, and anaerobically fermented at 35°C and 60rpm for 125 hours, and sterilized to obtain product S3;

[0092] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0093] Extract 11:

[0094] S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of 1:1 to obtain a mixture, add 1 times the mass of water of the mixture, beat, then add 20 times the mass of water of the mixture, mix, and obtain product S1;

[0095] S2: Add 300u / g trypsin to product S1, stir at 47°C and 60rpm for 3.5 hours, inactivate the enzyme, and obtain product S2;

[0096] S3: Add 2.2% glucose and 0.025% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 1.20×10 10 cfu / g pre-fermentation was inoculated with fermentation bacteria, the fermentation bacteria was Lactobacillus plantarum CI CC 20717, and anaerobically fermented at 35°C and 60rpm for 125 hours, sterilized, and obtained product S3;

[0097] S4: The product S3 was filtered through a filter membrane with a pore size of 0.22 μm, and the filtrate was freeze-dried at -38°C to a water content of 1.54 wt%, to obtain the extract.

[0098] 2. Rice noodles

[0099] Rice noodle 1:

[0100] The preparation method is as follows:

[0101] Step 1: Grind indica rice and glutinous rice separately, sieve with a 120-mesh sieve, and select the sieved powder to obtain indica rice flour and glutinous rice flour;

[0102] Step 2: According to weight parts, 120 parts of indica rice flour and 18 parts of glutinous rice flour are mixed to obtain a mixed powder, and 0.70 parts of the functional raw material (the above-mentioned extract 1) is mixed with 70 parts of water to obtain a solution;

[0103] Step 3: Add the mixed solution to the mixed powder, stir and knead into dough;

[0104] Step 4: placing the dough in an extruder and extruding it, and then cutting it to obtain a crude rice noodle product; the specifications of the crude product: 0.8 mm in diameter, 15 cm in length;

[0105] Step 5: introducing water vapor at 120° C. into a constant temperature chamber and placing the rice noodles in the constant temperature chamber for aging for 7 min, and freeze-drying (freeze drying) at -40° C. to a water content of 3.67 wt %, to obtain the rice noodles.

[0106] Rice Noodle 2:

[0107] The preparation method is as follows:

[0108] Step 1: Grind indica rice and glutinous rice separately, sieve with a 120-mesh sieve, and select the sieved powder to obtain indica rice flour and glutinous rice flour;

[0109] Step 2: According to weight parts, 140 parts of indica rice flour and 22 parts of glutinous rice flour are mixed to obtain a mixed powder, and 0.81 parts of the functional raw material (the above-mentioned extract 2) is mixed with 80 parts of water to obtain a solution;

[0110] Step 3: Add the mixed solution to the mixed powder, stir and knead into dough;

[0111] Step 4: placing the dough in an extruder and extruding it, and then cutting it to obtain a crude rice noodle product; the specifications of the crude product: 0.8 mm in diameter, 15 cm in length;

[0112] Step 5: introducing water vapor at 125° C. into a constant temperature chamber and placing the rice noodles in the constant temperature chamber for aging for 6.5 min, and freeze-drying (freeze drying) at -40° C. to a water content of 3.59 wt %, to obtain the rice noodles.

[0113] Rice Noodle 3:

[0114] Step 1: Grind indica rice and glutinous rice separately, sieve with a 120-mesh sieve, and select the sieved powder to obtain indica rice flour and glutinous rice flour;

[0115] Step 2: According to weight parts, 120 parts of indica rice flour and 18 parts of glutinous rice flour are mixed to obtain mixed flour;

[0116] Step 3: Add 70 parts of water to the mixed flour, stir and knead into dough;

[0117] Step 4: placing the dough in an extruder and extruding it, and then cutting it to obtain a crude rice noodle product; the specifications of the crude product: 0.8 mm in diameter, 15 cm in length;

[0118] Step 5: introducing water vapor at 120° C. into a constant temperature chamber and placing the rice noodles in the constant temperature chamber for aging for 7 min, and freeze-drying (freeze drying) at -40° C. to a water content of 3.67 wt %, to obtain the rice noodles.

[0119] Rice Noodles 4:

[0120] The preparation method is as follows:

[0121] Step 1: Grind the indica rice into powder, sieve it with a 120-mesh sieve, select the sieved powder, and obtain indica rice powder;

[0122] Step 2: According to parts by weight, 0.70 parts of the functional raw material (the extract 1) and 70 parts of water are mixed to obtain a solution;

[0123] Step 3: Add the mixed solution to 138 parts of indica rice flour, stir and knead into dough;

[0124] Step 4: placing the dough in an extruder and extruding it, and then cutting it to obtain a crude rice noodle product; the specifications of the crude product: 0.8 mm in diameter, 15 cm in length;

[0125] Step 5: introducing water vapor at 120° C. into a constant temperature chamber and placing the rice noodles in the constant temperature chamber for aging for 7 min, and freeze-drying (freeze drying) at -40° C. to a water content of 3.67 wt %, to obtain the rice noodles.

[0126] Rice Noodles 5:

[0127] The preparation method is as follows:

[0128] Step 1: Grind indica rice and glutinous rice separately, sieve with a 120-mesh sieve, and select the sieved powder to obtain indica rice flour and glutinous rice flour;

[0129] Step 2: According to weight parts, 80 parts of indica rice flour and 58 parts of glutinous rice flour are mixed to obtain a mixed powder, and 0.70 parts of the functional raw material (the above-mentioned extract 1) is mixed with 70 parts of water to obtain a solution;

[0130] Step 3: Add the mixed solution to the mixed powder, stir and knead into dough;

[0131] Step 4: placing the dough in an extruder and extruding it, and then cutting it to obtain a crude rice noodle product; the specifications of the crude product: 0.8 mm in diameter, 15 cm in length;

[0132] Step 5: introducing water vapor at 120° C. into a constant temperature chamber and placing the rice noodles in the constant temperature chamber for aging for 7 min, and freeze-drying (freeze drying) at -40° C. to a water content of 3.67 wt %, to obtain the rice noodles.

[0133] 3. Testing

[0134] 1. Test on improving digestion effect

[0135] The extract was used to promote the release of flavonoids in vitro to verify the extent to which the extract improved digestion. The test method is as follows:

[0136] 1.1 Experimental materials:

[0137] Test samples: The above extracts 1-11 were respectively mixed with water at a mass ratio of 1:49 to obtain test samples 1-11;

[0138] Wheat flour: sieve through 120 mesh;

[0139] Simulated gastric fluid: 0.2 g pepsin mixed with 5 g 0.01 mol / L hydrochloric acid;

[0140] 1.2 Pre-treatment

[0141] Pretreatment of test samples: Mix 200g of test samples 1-11 with 20g of wheat flour respectively, and stir at 60rpm in a boiling water bath for 20min. Then cool to room temperature, add water to the original weight, adjust the pH to 2 with hydrochloric acid, add 2.5mL of simulated gastric juice, and digest for 80min in a light-proof, 37℃ water bath shaker. Digest on a shaker for 40min and 80min, centrifuge the digested liquid at 4℃ and 1500rpm for 20min, take the supernatant and add acetone to a concentration of 80wt% acetone, and then take the clear liquid as the experimental sample for the test in step 1.3. Set up a blank group, replace the 200g test sample in the pretreatment process of the test sample with 200g water, and the rest are the same to obtain a blank sample.

[0142] 1.3 Sample testing

[0143] Take 10g of the above sample (experimental sample or blank sample) and add an 80% ethanol aqueous solution of equal mass concentration, extract at 52℃, 60rpm for 120min, then centrifuge at 4500rpm for 15min; take 10mL of supernatant, add 0.7mL, 5wt% sodium nitrite aqueous solution, mix, and let stand for 6min; then add 0.7mL, 10wt% aluminum nitrate aqueous solution, mix, and let stand for 6min; then add 5mL, 4wt% sodium hydroxide aqueous solution, shake well, use 80% ethanol aqueous solution to make the volume 25mL, and let stand at room temperature and light for 30min. Pour into a centrifuge tube, centrifuge at 5000rpm for 10min, take the supernatant and measure the absorbance at 510nm colorimetrically, convert the flavonoid release K value (unit mg / 100g) in the digestive juice at different times (40, 80min), and test each group in parallel 5 times to take the average value. The results are shown in Table 1.

[0144] Table 1: K values ​​of different extract groups at different treatment times

[0145] Serial number K value at 40min / mg / 100g K value at 80min / mg / 100g Extract 1 307.82 377.53 Extract 2 306.97 375.92 Extract 3 303.58 369.37 Extract 4 306.13 374.24 Extract 5 305.01 372.11 Extract 6 290.15 343.50 Extract 7 299.89 362.27 Extract 8 298.96 360.45 Extract 9 303.14 368.53 Extract 10 304.76 371.64 Extract 11 297.78 358.15 Blank Group 271.53 313.72

[0146] According to the test data in Table 1, the difference △K value of the K value of each extract group compared with the blank group at 40min and 80min was calculated. The specific data results are shown in Table 2.

[0147] Table 2: △K values ​​of different extract groups at different treatment times and blank group

[0148] Serial number △K value at 40min / mg / 100g △K value at 80min / mg / 100g Extract 1 36.29 63.81 Extract 2 35.44 62.2 Extract 3 32.05 55.65 Extract 4 34.60 60.52 Extract 5 33.48 58.39 Extract 6 18.62 29.78 Extract 7 28.36 48.55 Extract 8 27.43 46.73 Extract 9 31.61 54.81 Extract 10 33.23 57.92 Extract 11 26.25 44.43

[0149] According to the test results in Table 1-2, the extract prepared by the present invention can effectively aid digestion and give the rice noodles a better effect.

[0150] According to the test of extracts 1 and 3, the use of trypsin can enhance the digestive effect of the extracts to a great extent.

[0151] According to the tests on extracts 1, 4-5, the combination of dried tangerine peel and dried mulberry for extraction can enrich the types and richness of digestive active ingredients in the extracts, produce a complementary effect, and promote each other to enhance the digestive effect.

[0152] According to the test of extracts 1 and 11, the present invention uses Lactobacillus fermentum 1.1796 and Lactobacillus acidophilus 1.1807 for fermentation, which can enhance the digestive effect of the extracts compared with other bacteria.

[0153] According to the test of extracts 1, 7-8, the use of fermented lactobacillus 1.1796 and lactobacillus acidophilus 1.1807 for joint fermentation can synergistically improve the digestion-aiding ability of the extract, making rice noodles easier to be accepted and eaten by different groups of people. And when fermented lactobacillus 1.1796 and lactobacillus acidophilus 1.1807 are used in a quantity ratio of 2-3.5:1 during the fermentation and extraction process, the effect of the prepared extract is better, and the above content can be obtained in combination with the test results of extracts 1, 9-10.

[0154] 2. Comprehensive effect test of rice noodles

[0155] The test indicators include color, hardness, stickiness, aroma and digestibility. The specific experimental process is: 40 healthy volunteers aged 30-40 were selected and randomly divided into 5 groups with 8 people in each group to evaluate the rice noodles; the rice noodles were boiled in boiling water for 8 minutes, taken out, and the color and aroma were evaluated. Then each volunteer ate the rice noodles corresponding to each group and evaluated the hardness and stickiness based on the feeling of fullness. A follow-up visit was conducted 3 hours after eating to evaluate the digestibility of the rice noodles.

[0156] Among them, the color is judged by high gloss and brightness; the hardness is judged by moderate hardness, neither too hard nor too soft is good; the stickiness is judged by being refreshing but not sticky to the teeth, neither too sticky or sticky to the teeth is good; the aroma is evaluated by the rice aroma, the stronger the rice aroma, the higher the score; the digestibility is evaluated by whether it is suitable for the stomach and the higher the degree of digestion of the rice noodles is felt, the higher the score.

[0157] The theoretical maximum score of each test index is 10 points, and the theoretical minimum score is 1 point. Decimal scores can be given according to actual conditions. The total scores of the eight people for each index of each group of rice noodles are summarized, and the results are shown in Table 3.

[0158] Table 3: Summary of total scores of indicators

[0159] Serial number / total score Color hardness viscosity aroma Digestibility Rice noodle 1 73.4 72.6 70.5 72.6 74.1 Rice Noodles 2 74.1 72.0 69.7 72.1 73.8 Rice Noodles 3 73.8 73.1 70.8 72.9 60.5 Rice Noodles 4 74.7 68.4 73.1 67.2 76.2 Rice noodle 5 71.0 61.3 62.9 73.5 69.7

[0160] According to the test results in Table 3, the rice noodles prepared by the present invention have excellent color, moderate hardness, are non-sticky, have a strong rice flavor and are easy to digest, and have good application prospects.

[0161] According to the rice noodle tests 1 and 3, the extract can effectively improve the digestibility of rice noodles, so that people who eat them can better digest rice noodles or other foods after eating a large amount. At the same time, it can also be eaten by people with insufficient digestive ability.

[0162] Comparing rice noodles 1 and 4 in Table 3, it can be seen that the absence of glutinous rice in rice noodle 4 resulted in a low score and reduced aroma due to excessive hardness. It can be seen that the addition of glutinous rice can increase the rice aroma of the rice noodles while reducing the defect of the rice noodles being too hard.

[0163] From the comparison of rice noodles 1 and 5 in Table 3, it can be seen that the use of a large amount of glutinous rice in rice noodles can increase the aroma, but the color is reduced to a certain extent, and the hardness and stickiness are reduced, which will also greatly affect the degree of digestion of the rice noodles.

[0164] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing rice noodles, characterized in that: The steps include: Step 1: Grind and sieve indica rice and glutinous rice separately to obtain indica rice flour and glutinous rice flour; Step 2: Mix indica rice flour and glutinous rice flour according to weight to obtain a mixed powder, and mix the functional raw material with water to obtain a solution; Step 3: Add the mixed solution to the mixed powder, stir and knead into dough; Step 4: placing the dough in an extruder for extrusion, and then cutting it to obtain a crude rice noodle product; Step 5: The crude rice noodles are matured in a constant temperature room, freeze-dried, and sterilized to obtain the rice noodles.

2. The preparation method according to claim 1, characterized in that: The mesh number of the sieve used for screening is greater than 50 mesh.

3. The preparation method according to claim 1, characterized in that: In step 2, the raw materials used are in the following amounts, by weight: 100-150 parts of indica rice flour, 10-25 parts of glutinous rice flour, 0.1-1 parts of functional raw materials and 50-80 parts of water.

4. The preparation method according to claim 1, characterized in that: The diameter of the thick rice noodles is 0.5-2mm.

5. The preparation method according to claim 1, characterized in that: The length of the thick rice noodles is not limited to 10-30cm.

6. The preparation method according to claim 1, characterized in that: The rice noodles are cooked by passing water vapor at 110-130°C into the constant temperature chamber.

7. The preparation method according to claim 1, characterized in that: The ripening time is 6-10 minutes.

8. Rice noodles prepared according to the preparation method according to any one of claims 1 to 7.

9. Use of the rice noodles according to claim 8 in preparing instant food.

10. The preparation method according to any one of claims 1 to 7 or the rice noodles according to claim 8 or the use according to claim 9, characterized in that: The functional raw materials are extracts of dried tangerine peel and dried mulberries, and the preparation method of the extract comprises the following steps: S1: Wash and drain dried tangerine peel and dried mulberries, mix them in a mass ratio of tangerine peel to mulberries of 1:0.8-1.2 to obtain a mixture, add 0.5-1.5 times the mass of the mixture of water, beat, and then add 10-40 times the mass of the mixture of water to mix, to obtain product S1; S2: Add trypsin in an amount of 200-400 u / g of product S1 to product S1, perform enzymolysis at 40-50° C. for 2-4 hours, inactivate the enzyme, and obtain product S2; S3: Add 0.5-3% glucose and 0.001-0.05% potassium dihydrogen phosphate to product S2, sterilize, and obtain a pre-fermented product. Then, inoculate 7.5×10 9 -2.7×10 10 cfu / g pre-fermented material is inoculated with fermentation bacteria, wherein the fermentation bacteria are composed of Lactobacillus fermentum 1.1796 and Lactobacillus acidophilus 1.1807 in a quantity ratio of 2-3.5:1, and the fermentation is stirred at 25-40°C for 70-140 hours, sterilized, and a product S3 is obtained; S4: Filter the product S3 and dry it to obtain the extract.