Extruded cooked noodles and preparation method thereof

Abstract

The invention provides extruded cooked noodles and a preparation method thereof, and belongs to the technical field of foods. The invention provides extruded cooked noodles which are prepared from the following raw materials in percentage by mass: 20-80% of wheat flour and 20-80% of cassava starch. According to the extruded cooked noodles provided by the invention, the wheat flour and the cassava starch are compounded, and under the synergistic effect of a good gel network and high amylopectin content of the cassava starch and a gluten protein network in the wheat flour, the prepared extruded cooked noodles are soft and smooth in mouth feel, and have very good tensile property and cooking quality; compared with common extruded cooked noodles, the texture characteristics of the noodles are obviously improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of food, and particularly relates to an extruded cooked noodle and a preparation method thereof. Background Art

[0002] As an important staple food, the production process of noodles mostly uses the rolling method. However, the traditional rolling method relies on multiple processes to repeatedly roll the noodle sheets, which has limitations such as complex processes and large equipment footprint. The extrusion technology can quickly form the dough through high-temperature shearing, with the advantages of simple process flow and compact equipment, significantly promoting the industrialization process of noodles. Although the extruded cooked noodles present a unique smooth and Q-bouncing texture, they are prone to quality defects such as high cooking loss and decreased stretchability after rehydration, and it is difficult to meet the high-standard requirements of consumers for texture characteristics.

[0003] Current research focuses on improving the nutritional value of extruded pasta through raw material innovation, such as using miscellaneous grains like chickpea flour and broad bean flour to replace wheat flour. However, such improvements are often accompanied by texture deterioration: for example, adding active gluten can improve cooking performance but results in decreased stretchability; soy protein fortification can reduce cooking loss but causes a decline in stretchability. This indicates that the texture improvement of extruded cooked noodles has a long way to go and urgently requires a breakthrough solution. Summary of the Invention

[0004] Aiming at the defects in the prior art, the purpose of the present invention is to provide an extruded cooked noodle, which can effectively solve the problems of poor stretchability and high cooking loss of extruded cooked noodles after rehydration.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] The present invention provides an extruded cooked noodle. Calculated by mass percentage, the raw materials for preparation include: 20% - 80% of wheat flour and 20% - 80% of tapioca starch.

[0007] Preferably, the raw materials for preparation of the extruded cooked noodle include: 40% - 60% of wheat flour and 40% - 60% of tapioca starch.

[0008] Preferably, the raw materials for preparation of the extruded cooked noodle include: 50% of wheat flour and 50% of tapioca starch;

[0009] Alternatively, the raw materials for preparation of the extruded cooked noodle include: 40% of wheat flour and 60% of tapioca starch;

[0010] Alternatively, the raw materials for preparation of the extruded cooked noodle include: 60% of wheat flour and 40% of tapioca starch;

[0011] Alternatively, the raw materials for preparation of the extruded cooked noodle include: 80% of wheat flour and 20% of tapioca starch;

[0012] Alternatively, the raw materials for preparing the extruded cooked noodles include: 20% wheat flour and 80% tapioca starch.

[0013] The present invention provides a method for preparing the extruded cooked noodles according to the above technical solution, including:

[0014] Mix wheat flour and tapioca starch to obtain a flour composition;

[0015] Mix the flour composition with water and adjust the slurry to obtain a slurry;

[0016] Extrude, age and dry the slurry to obtain extruded cooked noodles.

[0017] Preferably, the mass ratio of the flour composition to water is (2-3):(2-3).

[0018] Preferably, the temperature of the extrusion cooking is 95-105°C.

[0019] Preferably, the speed of the extrusion cooking is 7-9 mm / s.

[0020] Preferably, the temperature of the aging is 2-6°C; the time of the aging is 10-15 h.

[0021] Preferably, the diameter of the extrusion outlet during the extrusion cooking is 1.2-1.8 mm.

[0022] Preferably, the temperature of the drying is 45-55°C; dry until the moisture content of the extruded cooked noodles drops to ≤15%.

[0023] Advantages of the present invention:

[0024] The present invention provides an extruded cooked noodle. By mass percentage, the raw materials for preparation include: 20%-80% wheat flour and 20%-80% tapioca starch. The extruded cooked noodle provided by the present invention combines wheat flour and tapioca starch. Under the synergistic effect of the good gel network of tapioca starch, the relatively high amylopectin content and the gluten protein network in wheat flour, the obtained extruded cooked noodles are soft, have a smooth taste, and have good tensile properties and cooking quality, significantly improving the texture characteristics of the noodles compared with ordinary extruded cooked noodles. Compared with the control group of extruded cooked noodles prepared with pure wheat flour, when the mass ratio of wheat flour to tapioca starch is 1:1, the breaking elongation rate of the noodles increases from 150% to 750%, an increase of about 5 times. The cooking loss decreases from 20.08% to 5.93%, a decrease of about 3 times, and at the same time has good elastic and chewable eating qualities. The extruded cooked noodle provided by the present invention provides a new strategy for solving the problems of poor stretchability and poor cooking quality of extruded cooked noodles. Description of the Drawings

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0026] Figure 1 It is the stress-strain curve graph of the extruded cooked noodles for Examples 1 to 5 and Comparative Examples 1 to 2;

[0027] Figure 2 It is the microstructural diagram of the extruded cooked noodles for Examples 1 to 5 and Comparative Examples 1 to 2. Detailed implementation manners

[0028] The present invention provides an extruded cooked noodle. By mass percentage, the raw materials for preparation include: 20% - 80% of wheat flour and 20% - 80% of tapioca starch.

[0029] In the following technical solutions, unless otherwise specified, the present invention does not have special limitations on the sources of each raw material, and conventional commercially available products in the art can be used.

[0030] As an optional implementation manner of the present invention, by mass percentage, the raw materials for preparing the extruded cooked noodle include 20% - 80% of wheat flour, which can also be 20%, 30%, 40%, 50%, 60%, 70% or 80%. In the present invention, the wheat flour includes wheat flour.

[0031] As an optional implementation manner of the present invention, by mass percentage, the raw materials for preparing the extruded cooked noodle include 20% - 80% of tapioca starch, which can also be 20%, 30%, 40%, 50%, 60%, 70% or 80%. The present invention uses a certain proportion of tapioca starch as the raw material for noodles. The tapioca starch has advantages such as a high amylopectin content, high viscosity, and a good gel network, which can endow the noodle product with excellent swelling properties, and thus is beneficial to improving the texture characteristics of the noodle product.

[0032] As an optional implementation manner of the present invention, for the extruded cooked noodle, by mass percentage, the raw materials for preparation can be: 80% of wheat flour and 20% of tapioca starch.

[0033] As an optional implementation manner of the present invention, for the extruded cooked noodle, by mass percentage, the raw materials for preparation can be: 60% of wheat flour and 40% of tapioca starch.

[0034] As an optional implementation manner of the present invention, for the extruded cooked noodle, by mass percentage, the raw materials for preparation can be: 50% of wheat flour and 50% of tapioca starch.

[0035] As an alternative embodiment of the present invention, for the extruded cooked noodles, by mass percentage, the raw materials for preparation can be: 40% wheat flour and 60% tapioca starch.

[0036] As an alternative embodiment of the present invention, for the extruded cooked noodles, by mass percentage, the raw materials for preparation can be: 20% wheat flour and 80% tapioca starch.

[0037] In the extruded cooked noodles provided by the present invention, wheat flour and tapioca starch are innovatively compounded. Tapioca starch has advantages such as a high amylopectin content, high viscosity, and a good gel network, which can endow the noodle products with excellent swelling properties. With the synergistic effect of the good gel network of tapioca starch and the relatively high amylopectin content and the gluten protein network in wheat flour, the extruded cooked noodles prepared are soft, smooth in taste, and have good tensile properties and cooking quality.

[0038] The present invention provides a method for preparing the extruded cooked noodles according to the above technical solution, including:

[0039] Mix wheat flour and tapioca starch to obtain a flour composition;

[0040] Mix the flour composition with water and then adjust the slurry to obtain a slurry;

[0041] Subject the slurry to extrusion cooking, aging, and drying to obtain extruded cooked noodles.

[0042] The present invention mixes wheat flour and tapioca starch to obtain a flour composition. The present invention has no special limitation on the mixing method, and any conventional mixing method in the art can be used.

[0043] After obtaining the flour composition, the present invention mixes the flour composition with water and then adjusts the slurry to obtain a slurry. As an alternative embodiment of the present invention, the mass ratio of the flour composition to water can be (2 - 3):(2 - 3), or can also be 2:2, 2:3, or 3:2. The addition amount of water provided by the present invention is beneficial to obtaining noodles with better texture properties. In the present invention, the water can be deionized water. The present invention mixes the flour composition with water to obtain a flour-water mixture. After obtaining the flour-water mixture, the present invention adjusts the slurry of the flour-water mixture; the slurry adjustment includes manual slurry adjustment, and there is no special limitation on the slurry adjustment speed and time, until the flour composition and water are fully mixed without lumps; the slurry adjustment time can be 15 min. After the slurry adjustment is completed, a slurry is obtained.

[0044] After obtaining the slurry, the present invention preferably subjects the slurry to extrusion cooking, aging, and drying to obtain extruded cooked noodles. As an alternative embodiment of the present invention, the temperature of the extrusion cooking can be 95-105°C, or it can be 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, or 105°C; the speed of the extrusion cooking can be 7-9 mm / s, or it can be 7, 8, or 9 mm / s; the diameter of the extrusion outlet during the extrusion cooking can be 1.2-1.8 mm, or it can be 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, or 1.8 mm. As an alternative embodiment of the present invention, the extrusion cooking is preferably carried out using a single-screw extruder; when using a single-screw extruder for extrusion cooking, it is preferred to set the temperature of the single-screw extruder to the temperature of the extrusion cooking, then add the slurry into the single-screw extruder, and after starting the extruder, first let a small part of the slurry enter the inside of the extruder and pause for 3-5 minutes, and then start the extruder again to carry out the process of extrusion cooking. Pausing for 3-5 minutes can enable the slurry to be fully gelatinized in the extruder.

[0045] After obtaining the cooked noodles by extrusion cooking, the present invention preferably ages the obtained cooked noodles. As an alternative embodiment of the present invention, the temperature of the aging can be 2-6°C, or it can be 2, 3, 4, 5, or 6°C; the time of the aging can be 10-15 h, or it can be 10, 11, 12, 13, 14, or 15 h. As an alternative embodiment of the present invention, the aging is preferably carried out under sealed conditions. After the aging is completed, the present invention dries the aged noodles. The present invention has no special limitation on the method of the drying, and any conventional drying method in the art can be used. As an alternative embodiment of the present invention, the temperature of the drying can be 45-55°C, or it can be 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, or 55°C; dry until the moisture content of the extruded cooked noodles drops to ≤15%, which can be 10%-15%, or it can be 10%, 11%, 12%, 13%, 14%, or 15%; the time of the drying can be 4-5 h. As an alternative embodiment of the present invention, the drying can be carried out using a forced-air drying oven. After the drying is completed, the present invention obtains the extruded cooked noodles.

[0046] The method for preparing extruded cooked noodles provided by the present invention is simple and easy to implement, and is beneficial to endowing the noodles with better texture properties.

[0047] In order to further illustrate the present invention, the technical solutions provided by the present invention will be described in detail below with reference to the drawings and embodiments, but they cannot be understood as limiting the protection scope of the present invention.

[0048] All experiments in the following examples were repeated three or more times, and the data were expressed as mean ± standard deviation. The obtained data were statistically analyzed and processed using IBM SPSS Statistics 25.0 (SPSS Inc., Chicago, USA) software. Statistical significance was considered at the 95% level (p < 0.05). Origin 2022b (OriginLab Inc., USA) was used for graphing analysis.

[0049] Example 1

[0050] An extruded cooked noodle, calculated by mass percentage, the raw materials for preparation are: 80% wheat flour and 20% tapioca starch.

[0051] The preparation method of the extruded cooked noodle is as follows:

[0052] Fully mix the wheat flour and tapioca starch to obtain a flour composition;

[0053] Mix the flour composition and deionized water in a mass ratio of 2:2 for manual pulp making, stir during the pulp making process, and the stirring time is 15 min to obtain a slurry;

[0054] Set the temperature of the single-screw extruder to 100 °C. After the temperature rises, pour the slurry into it. After starting the extruder, first let a small part of the slurry enter the inside of the extruder and pause for 4 min, then start the extruder again. The diameter of the extrusion die is 1.5 mm, adjust the powder output speed to 8 mm / s, and extrude the noodles;

[0055] Seal and age the extruded noodles at 4 °C for 12 h.

[0056] Dry the aged noodles. Put the aged noodles into a blast drying oven at 45 °C and dry for 5 h until the moisture content of the noodles drops to 10% to obtain the extruded cooked noodles. The extruded cooked noodles prepared in this example are denoted as: NWT 8:2 group.

[0057] Example 2

[0058] An extruded cooked noodle, calculated by mass percentage, the raw materials for preparation are: 60% wheat flour and 40% tapioca starch.

[0059] The preparation method of the extruded cooked noodle is the same as that of Example 1. The extruded cooked noodles prepared in this example are denoted as: NWT 6:4 group.

[0060] Example 3

[0061] An extruded cooked noodle, calculated by mass percentage, the raw materials for preparation are: 50% wheat flour and 50% tapioca starch.

[0062] The method for preparing the extruded cooked noodles is the same as that in Example 1. The extruded cooked noodles prepared in this example are denoted as: NWT 5:5 Group.

[0063] Example 4

[0064] The invention discloses extruded cooked noodles, wherein the raw materials for preparing the noodles are: 40% of wheat flour and 60% of cassava starch in terms of mass percentage.

[0065] The method for preparing the extruded cooked noodles is the same as that in Example 1. The extruded cooked noodles prepared in this example are denoted as: NWT 4:6 Group.

[0066] Example 5

[0067] The invention discloses extruded cooked noodles, wherein the raw materials for preparing the noodles are: 20% of wheat flour and 80% of cassava starch in terms of mass percentage.

[0068] The method for preparing the extruded cooked noodles is the same as that in Example 1. The extruded cooked noodles prepared in this example are denoted as: NWT 2:8 Group.

[0069] Comparative Example 1

[0070] The invention discloses extruded cooked noodles, the raw material for preparing the noodles is wheat flour.

[0071] The method for preparing the extruded cooked noodles is the same as that in Example 1. The extruded cooked noodles prepared in this example are denoted as: NWT 10:0 Group.

[0072] Comparative Example 2

[0073] The invention discloses extruded cooked noodles, and the raw material used for preparing the noodles is cassava starch.

[0074] The method for preparing the extruded cooked noodles is the same as that in Example 1. The extruded cooked noodles prepared in this example are denoted as: NWT 0:10 Group.

[0075] Application Example 1

[0076] 1. The cooking characteristics of the extruded noodles prepared in Examples 1 to 5 and Comparative Examples 1 to 2 were measured.

[0077] The specific method is as follows: 10 g of each sample of the extruded cooked noodles prepared in Examples 1 to 5 and Comparative Examples 1 to 2 is weighed, recorded as m0, placed in 500 mL of boiling water, and boiled until the noodles are taken out without a hard core, which is the optimal cooking time. The surface water of the boiled noodles is absorbed and weighed, recorded as m1. The remaining water of the noodle sample after boiling is dried in an oven at 105°C and weighed, recorded as m2. 20 noodle samples with a length of 20 cm are selected, and after boiling them to the optimal boiling time, the number of noodles with a length of less than 10 cm is recorded as m3, and the boiling loss rate is determined.

[0078] The cooking properties of the rehydrated samples were calculated using formulas (1) to (3).

[0079] Rehydration rate (%) = m1 / m0 × 100%, formula (1);

[0080] Cooking loss (%) = m2 / m0 × 100%, formula (2);

[0081] Breaking rate (%) = m3 / 20 × 100%, formula (3).

[0082] The test results of the cooking properties of the extruded cooked noodles prepared in Examples 1 to 5 and Comparative Examples 1 to 2 are shown in Table 1.

[0083] Table 1 Cooking properties of the extruded cooked noodles prepared in Examples 1 to 5 and Comparative Examples 1 to 2

[0084] Group Rehydration rate / % Cooking loss / % Breaking rate / % Optimal cooking time / min <![CDATA[NWT 10:0 > <![CDATA[168.30±4.55 d > <![CDATA[20.08±0.56 a > 0 6.33±0.09g <![CDATA[NWT 8:2 > <![CDATA[172.13±1.97 d > <![CDATA[14.87±1.67 bc > 0 <![CDATA[7.57±0.09 f > <![CDATA[NWT 6:4 > <![CDATA[188.77±0.77 c > <![CDATA[14.03±0.37 c > 0 <![CDATA[9.40±0.10 e > <![CDATA[NWT 5:5 > <![CDATA[254.39±3.04 a > <![CDATA[5.93±0.12 e > 0 <![CDATA[9.86±0.13 d > <![CDATA[NWT 4:6 > <![CDATA[186.05±0.99 c > <![CDATA[11.92±2.11 d > <![CDATA[38.33% ± 0.08 a > <![CDATA[10.77±0.25 c > <![CDATA[NWT 2:8 > <![CDATA[197.49±1.70 b > <![CDATA[15.00±0.63 bc > <![CDATA[16.67% ± 0.29 b > <![CDATA[13.56±0.10 b > <![CDATA[NWT 0:10 > <![CDATA[197.08±4.67 b > <![CDATA[16.53±0.90 b > 0 <![CDATA[16.97±0.13 a >

[0085] Note: The data in the table represent the average value ± standard deviation of three repeated experiments. Different letters (a - d) in the same column indicate significant differences (p < 0.05).

[0086] As shown in Table 1, the water absorption rate generally shows an increasing trend with the increase in the proportion of cassava starch. This is because the rehydration time of the samples increases with the increase in the addition amount of cassava starch, so the water absorption rate also shows the same trend. However, when the ratio of wheat flour to cassava starch is 5:5, the maximum water absorption rate reaches 254.39%. It is speculated that this may be because NWT 5:5 contains both a gluten network structure and a gel network formed by cassava starch. Therefore, more water needs to be absorbed to obtain the best cooking quality. At the same time, a high water absorption rate means that the sample is smoother. The cooking loss shows a trend of first decreasing and then increasing with the increase in the proportion of cassava starch, and is the smallest when the ratio of wheat flour to cassava starch is 5:5, about 5.93%. This is because the amylose content in wheat starch is higher than that in cassava starch. In the previous several ratios, as the cassava starch increases and the wheat flour ratio decreases, less gluten - protein or lipid complex contained in the wheat flour dissolves out, so the cooking loss decreases first. In the subsequent several ratios, due to the decrease in wheat starch, the strength of the gel network becomes weaker and the internal starch dissolves out, resulting in an increase in the cooking loss. As can be seen from Table 1, only the two samples of NWT 4:6 and NWT 2:8 have the problem of broken noodles because the amylose content in cassava starch is relatively low and the strength of the gel network is weak, resulting in lower noodle hardness and softer gel, and it is easy to break during cooking.

[0087] 2. Use a texture analyzer (TA) to measure the tensile properties of the extruded cooked noodles of Examples 1-5 and Comparative Examples 1-2 respectively. Boil the samples in boiling water until the optimal cooking time. Then adsorb the water on the surface with filter paper, cool, measure using an A / TG probe, select the tensile target mode, set the parameters to 3 mm / s before the test, 1 mm / s during the test, and 3 mm / s after the test, set the automatic displacement trigger mode, set the strain height to 10 mm, and set the specimen parameters with a diameter of 1.5 mm. Measure each sample at least 5 times and take the average value to obtain the stress-strain curve. The results are shown in Table 2 and Figure 1 as shown, where Figure 1 are the stress-strain curve graphs of the extruded cooked noodles of Examples 1-5 and Comparative Examples 1-2.

[0088] Table 2 Tensile rate and maximum tensile stress of extruded cooked noodles

[0089] Group Elongation rate / % Tensile stress / KPa <![CDATA[NWT 10:0 > 157.75 5.02 <![CDATA[NWT 8:2 > 271.79 7.34 <![CDATA[NWT 6:4 > 375.29 8.04 <![CDATA[NWT 5:5 > 749.99 9.01 <![CDATA[NWT 4:6 > 331.79 6.17 <![CDATA[NWT 2:8 > 235.24 5.51 <![CDATA[NWT 0:10 > 575.69 3.60

[0090] The results are shown in Table 2 and as Figure 1 shown. The rehydrated tensile rate of the extruded cooked noodles made of pure wheat flour reaches 157.75% after drying. As the tapioca starch increases, the tensile rate gradually increases. When the compounding ratio of flour and tapioca starch is 5:5, the tensile rate reaches a maximum of 749.99%, and at the same time its maximum tensile stress is 9.01 KPa. This is because the tapioca starch has a high amylopectin content, which increases the tensile rate. At the same time, the gluten network in the flour also contributes to the tensile properties of the gel of this sample. The synergistic effect of the gluten network and the tapioca gel network endows the extruded cooked noodles with good elongation at break and breaking stress. Continuing to increase the proportion of tapioca starch, the tensile rate of the sample gel decreases. It is speculated that this may be because the gelatinization temperature of tapioca starch is lower than that of flour. Therefore, when extruded by a single-screw extruder, the tapioca starch is gelatinized while the wheat flour is not fully gelatinized. By the time the wheat flour is fully gelatinized, the tapioca starch is over-gelatinized, resulting in nodules in the gel during extrusion. Therefore, the elongation at break decreases during stretching. The rehydrated tensile rate of the gel made of pure tapioca starch reaches 575.69% after drying, and the minimum tensile stress is 3.60 KPa. This is because tapioca starch contains a high proportion of amylopectin and a low proportion of amylose. Among them, amylose can rapidly retrograde and form a hard gel network in a short time, while amylopectin helps to construct a soft gel network structure, endowing the noodle gel with good flexibility. When tapioca starch is used in combination with wheat flour, it will cause a decrease in the tensile strength of the noodles, but the elongation at break will be improved.

[0091] 3. The texture properties of the extruded cooked noodles of Examples 1-5 and Comparative Examples 1-2 were measured respectively. The noodle samples were cooked to the optimal cooking time, cooled, and then measured. Two compression tests were carried out using a P36R probe, with a compression deformation of 50%, a trigger force of 5 g, and the pre-test, mid-test, and post-test speeds all being 3 mm / s. At least three measurements were taken for each sample and the average value was calculated to obtain the data of hardness, adhesiveness, elasticity, cohesiveness, chewiness, and springiness. The results are shown in Table 3.

[0092] Table 3 Texture properties of the extruded cooked noodles of Examples 1-5 and Comparative Examples 1-2

[0093] Group Hardness / g Viscosity / g·s Elasticity Adhesiveness Chewiness Springiness <![CDATA[NWT 10:0 > <![CDATA[276.03±0.19 a > <![CDATA[-3.05±1.31 a > <![CDATA[0.86±0.02 c > <![CDATA[0.79±0.010 e > <![CDATA[170.07±0.40 a > <![CDATA[0.61±0.01 b > <![CDATA[NWT 8:2 > <![CDATA[173.76±1.47 b > <![CDATA[-4.23±0.16 a > <![CDATA[0.89±0.002 b > <![CDATA[0.86±0.004 d > <![CDATA[139.63±0.19 b > <![CDATA[0.66±0.02 a > <![CDATA[NWT 6:4 > <![CDATA[127.26±1.00 c > <![CDATA[-4.38±1.01 a > <![CDATA[0.94±0.05 a > <![CDATA[0.87±0.005 cd > <![CDATA[106.85±0.82 c > <![CDATA[0.52±0.00071 c > <![CDATA[NWT 5:5 > <![CDATA[94.80±1.43 d > <![CDATA[-8.25±0.05 b > <![CDATA[0.92±0.01 a > <![CDATA[0.87±0.004 c > <![CDATA[79.12±2.15 d > <![CDATA[0.44±0.004 de > <![CDATA[NWT 4:6 > <![CDATA[84.82±0.43 e > <![CDATA[15.45±1.15b c > <![CDATA[0.93±0.01 a > <![CDATA[0.89±0.006 b > <![CDATA[64.98±1.04 e > <![CDATA[0.42±0.00071 e > <![CDATA[NWT 2:8 > <![CDATA[55.73±2.45 f > <![CDATA[18.24±1.63 cd > <![CDATA[0.94±0.01 a > <![CDATA[0.92±0.004 a > <![CDATA[62.14±0.71 f > <![CDATA[0.46±0.01 d > <![CDATA[NWT 0:10 > <![CDATA[52.31±0.08 g > <![CDATA[-18.94±2.56 d > <![CDATA[0.94±0.03 a > <![CDATA[0.92±0.0007 a > <![CDATA[54.47±0.49 g > <![CDATA[0.42±0.002 e >

[0094] Note: The data in the table represent the average value ± standard deviation of three repeated experiments. Different letters (a-f) in the same column indicate significant differences (p < 0.05).

[0095] As can be seen from Table 3, as the proportion of cassava starch increases, the hardness of the rehydrated noodles decreases from 276.03 ± 0.19 to 52.31 ± 0.08, a decrease of 223.72 g, and the elasticity increases from 0.86 ± 0.02 to 0.94 ± 0.03, while the resilience decreases. This is because cassava starch has a low amylose content and a low gel network strength, making it softer and more glutinous. In the NWT 5:5 sample, the hardness decreased by about 181.23 g compared to the control sample (NWT 10:0 ), and the elasticity reached about 0.92. Therefore, after compounding cassava starch, the extruded cooked noodles will have better elasticity. The adhesiveness increases, and the gumminess and chewiness show a significant decreasing trend as the proportion of flour decreases. This is mainly related to the low amylose content and high amylopectin content of cassava starch. Since the amylose content in cassava starch is low, it indicates that the addition of cassava starch significantly reduces the gel strength of the system.

[0096] 4. The microstructures of the extruded cooked noodles of Examples 1-5 and Comparative Examples 1-2 were measured respectively. The samples were cooked to the optimal cooking time and then freeze-dried, manually broken, placed on the sample stage for sputtering, and the network structure of the cross-section of the gel samples was observed by a scanning electron microscope ((SEM, S-4800, Hitachi Instruments Ltd., Tokyo, Japan)) under a test voltage of 10 kV and a current of 10 μA. The results are as Figure 2 shown. Figure 2 are the microstructural diagrams of the extruded cooked noodles of Examples 1-5 and Comparative Examples 1-2. Figure 2 In which, a is the observation result diagram of the microstructure of the NWT 10:0 group of noodles; b is the observation result diagram of the microstructure of the NWT 8:2 group of noodles; c is the observation result diagram of the microstructure of the NWT 6:4Microstructure observation results of a group of noodles; d is NWT 5:5 Microstructure observation results of a group of noodles; e is NWT 4:6 Microstructure observation results of a group of noodles; f is NWT 2:8 Microstructure observation results of a group of noodles; g is NWT 0:10 Microstructure observation results of a group of noodles.

[0097] It can be seen from Figure 2 that when the compounding ratio of cassava starch is 0-50%, with the increase of the addition amount of cassava starch, the network structure of the noodles gradually becomes compact, the mesh holes are small and dense, and the pore diameter decreases from 10 μm - 20 μm (NWT 10:0 ) to about 5 μm (NWT 5:5 ). It is speculated that due to the addition of cassava starch, the cassava starch molecules are well filled into the gluten network of the flour. At the same time, the gluten network in the flour and the cassava starch form a dense gel network after gelatinization and retrogradation, which also explains why the tensile strain is the highest when the compounding ratio of flour and cassava starch is 5:5. When the compounding ratio is 4:6 and 2:8, the mesh holes suddenly become larger, the pore diameter is basically about 30 μm, and the network gradually becomes loose. When the compounding ratio of flour and cassava starch is 2:8, it can be clearly seen that the network structure becomes disordered and the pore walls are no longer continuous and complete, so the hardness and tensile properties decrease. This may be because the addition of a large amount of cassava starch destroys the original gluten network, or it may be because the starch gel structure is damaged due to excessive gelatinization of cassava starch, inhibiting the formation of a dense network, resulting in discontinuous pore walls and poor tensile properties. The mesh holes of pure cassava starch gel are small and dense, because at this time the gel only has a uniform network structure of cassava starch, the pore walls are continuous, and the mesh holes are dense.

[0098] In summary. After compounding cassava starch, the tensile properties of extruded cooked noodles are improved, the cooking loss is reduced, the cooking quality is improved, and the noodles have a smooth and elastic texture. This method can effectively improve the texture of extruded cooked noodles and provides a new method for improving the quality of extruded cooked noodles.

[0099] Although the above embodiments have described the present invention in detail, they are only a part of the embodiments of the present invention, not all of them. People can also obtain other embodiments according to these embodiments without creative efforts, and these embodiments all belong to the protection scope of the present invention.

Claims

1. An extruded cooked noodle, characterized in that, By mass percentage, the raw materials for preparation include: 20% - 80% wheat flour and 20% - 80% tapioca starch.

2. The extruded cooked noodles according to claim 1, wherein The raw materials for preparing the extruded cooked noodles include: 40% - 60% wheat flour and 40% - 60% tapioca starch.

3. The extruded cooked noodles according to claim 1, characterized in that, The raw materials for preparing the extruded cooked noodles include: 50% wheat flour and 50% tapioca starch; Or, the raw materials for preparing the extruded cooked noodles include: 40% wheat flour and 60% tapioca starch; Or, the raw materials for preparing the extruded cooked noodles include: 60% wheat flour and 40% tapioca starch; Or, the raw materials for preparing the extruded cooked noodles include: 80% wheat flour and 20% tapioca starch; Or, the raw materials for preparing the extruded cooked noodles include: 20% wheat flour and 80% tapioca starch.

4. The preparation method of the extruded cooked noodles according to any one of claims 1 to 3, characterized in that, Include: Mix wheat flour and tapioca starch to obtain a flour composition; Mix the flour composition with water and adjust the slurry to obtain a slurry; Extrude, age and dry the slurry to obtain extruded cooked noodles.

5. The preparation method according to claim 4, characterized in that, The mass ratio of the flour composition to water is (2 - 3):(2 - 3).

6. According to the preparation method described in claim 4, wherein, The temperature of the extrusion cooking is 95 - 105°C.

7. According to the preparation method described in claim 4, characterized in that, The speed of the extrusion cooking is 7 - 9 mm / s.

8. The preparation method according to claim 4, wherein The temperature of the aging is 2 - 6°C; the aging time is 10 - 15 h.

9. The preparation method according to claim 4, characterized in that, The diameter of the extrusion die during extrusion cooking is 1.2 - 1.8 mm.

10. The preparation method according to claim 4, wherein The temperature of the drying is 45 - 55°C; dry until the moisture content of the extruded cooked noodles drops to ≤15%.

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