Processing method of buckwheat instant noodles with low oil content and fried instant noodles produced by processing method

Abstract

The invention discloses a processing method of buckwheat fried instant noodles with low oil content and fried instant noodles produced by the processing method, and belongs to the field of food processing, and the processing method comprises the following steps: mixing wheat flour, buckwheat core flour, auxiliary materials and water for 5-30 minutes to form a dough, fermenting for 5-60 minutes at the temperature of 20-40 DEG C, forming, steaming for 1.5-7 minutes under the condition of 0.1-0.2 MPa, and frying for 40-120 seconds under the condition of 140-160 DEG C; the buckwheat core flour is rich in starch aggregates (exposed starch clusters, complete endosperm cells and fragments thereof), is subjected to or not subjected to thermal modification treatment, has the particle size ranges that D10 is 4-10 microns, D50 is 20-35 microns and D90 is 60-90 microns, the mass of the buckwheat core flour accounts for 5-50% of the total mass of the wheat flour and the buckwheat core flour, and the addition amount of water accounts for 28-40% of the total mass of the wheat flour and the buckwheat core flour. The method for reducing the oil content of the fried instant noodles, provided by the invention, is simple to operate and easy for industrial production. The fried instant noodles produced by the method disclosed by the invention not only are low in oil content and short in rehydration time, but also have buckwheat flavor and strong edibility, and have wide market prospects.

Description

Technical field:

[0001] The invention relates to a processing method of low-oil-content buckwheat instant noodles and fried instant noodles produced thereby, belonging to the field of food processing. Background technology:

[0002] Fried instant noodles are a kind of instant food made of wheat flour, starch and water as the main raw materials, and improvers and emulsifiers as auxiliary materials, through key processes such as dough mixing, proofing, molding, steaming and frying. Fried instant noodles are favored by instant food consumers around the world because of their low cost, convenience and good flavor, and occupy a large market share both at home and abroad. In recent years, under the guidance of the concept of healthy diet, consumers pay more attention to the nutritional characteristics of instant noodles in addition to the edible quality. Fried instant noodles are a kind of fried food with a fat content of nearly 16-24% and a carbohydrate content of 60-75%. They are high-fat and high-energy foods. Long-term and large-scale consumption may induce chronic diseases such as obesity, high cholesterol and high blood pressure. Therefore, controlling the fat content of instant noodles and developing low-fat, low-energy and high-quality instant noodles processing technology are of great significance to the long-term development of the instant noodles production industry.

[0003] With the rise of the transformation and utilization of grain resources, grains such as buckwheat are widely used in food production. Buckwheat has the characteristics of high dietary fiber content (7.0-10.9%), high resistant starch content (27-33.5%), and rich functional substances. Using buckwheat flour to prepare pasta food is an effective strategy for developing low-energy healthy staple foods, but the product quality is not ideal when buckwheat flour is used alone to process food. The main reason is that there is a lack of gluten protein in the protein composition of buckwheat, which makes it difficult for the protein to aggregate into a continuous and uniform network structure during the processing of whole buckwheat products. For example, after the whole buckwheat noodles are cooked, due to the lack of a network gluten structure, the stability of the internal structure of the noodles is only maintained by the gel network formed by gelatinized starch, which has the disadvantages of rough taste, easy to break, and difficult to rehydrate. To solve the above problems, the currently widely used technology is to mix buckwheat flour and wheat flour in a certain proportion to process noodle products.

[0004] At present, the main production processes of buckwheat flour include whole-grain grinding and roller milling. Among them, the whole buckwheat flour obtained by the whole-grain grinding process retains all the influencing components of buckwheat grains and is rich in dietary fiber. Due to the low processing precision, the quality of buckwheat flour is poor, the prepared products have a rough taste and poor edible quality. The roller milling process of buckwheat is similar to that of wheat, but because the texture of buckwheat grains is softer than that of wheat, the flour path is shorter. The 3-skin 4-core flour making process is often used to obtain 3B, 1S, 4M, coarse bran, fine bran and other flour flows, and the bran, core powder, coarse powder and whole buckwheat powder grades are obtained by mixing powder. Whole buckwheat flour is rich in dietary fiber, starch, protein, and has a high ash content. Recent studies have shown that adding whole buckwheat flour to wheat flour to make fried instant noodles not only does not reduce the oil content, but even increases the oil content. In addition, there are still the following technical difficulties in making fried instant noodles with whole buckwheat: first, the ash content is high, the color is dark, and the appearance of the instant noodles is poor; second, the whole buckwheat flour contains a high level of unsaturated fatty acids, which significantly reduces the shelf life of instant noodles, making it difficult for the instant noodles to reach the requirement of 6 months at room temperature; third, buckwheat flour is rich in flavonoid compounds such as rutin, which has antioxidant function but brings bitterness, affecting the taste of the product and consumer acceptance. Therefore, there are still difficult-to-solve quality problems in the processing of fried instant noodles with whole buckwheat flour. In comparison, buckwheat core flour is the product after the buckwheat bran is removed during the flour making process, or its thermally modified product. The main component is buckwheat starch rich in resistant starch, containing a small amount of protein and dietary fiber (<1.5%), low ash content (<1%), which is equivalent to ordinary refined white flour (~0.4-0.8%), and has good processing quality while retaining certain nutrients and proteins. It is a good raw material for processing high-quality buckwheat instant noodles. Similar to rice, quinoa, oats, and wheat B starch, buckwheat starch is a typical fine-granular starch (<~20μm), and its particle size is only ~5μm. The Chinese patent "Quality Improver for Fried Foods" (CN100384343C) reports that polysaccharide powders containing pectin, xanthan gum, guar gum, potato starch, etc. with a particle size of less than 20μm have the effect of reducing the oil content of fried instant noodles. Other studies have shown that wheat B starch fills and restructures the pores of potato fries, reducing the oil content of fried French fries. However, when the applicant conducted research on the use of buckwheat core powder to reduce the oil content of fried instant noodles, it was found that most of the buckwheat core powder (particle size <130μm) obtained by the roller milling process used in conventional buckwheat processing had a particle size of >20μm, indicating that it is difficult to obtain dispersed buckwheat starch particles by roller milling.This is because the size of buckwheat endosperm cells is 80-120μm, while the hardness of buckwheat grains is only 1 / 3 of that of wheat. Buckwheat grains are easily broken during the flour-making process. At the same time, due to the small force, its endosperm cells are not easily damaged compared to wheat endosperm cells. In addition, even if the endosperm cells are broken, the small buckwheat starch particles and large specific surface area, coupled with the presence of sticky components such as proteins and non-starch polysaccharides, promote the aggregation of buckwheat starch particles to form aggregates. Similar situations can also be observed during rice grinding and flour-making. Therefore, buckwheat core flour contains a large amount of starch aggregates (including exposed fine particle clusters, complete endosperm cells and their fragments) (. Figure 1 ). When the complete endosperm cell structure is retained in buckwheat core flour, the endosperm cell wall acts as a physical barrier to wrap the starch granules, inhibiting the expansion, gelatinization and digestion of starch. The low digestibility of buckwheat starch may be due to the easy aggregation of fine starch granules, which hinders the approach and action of amylase. Based on the above findings, it can be inferred that the use of buckwheat core flour rich in buckwheat starch aggregates to make fried instant noodles hinders the penetration of oil during frying and cold cutting because the aggregates are tightly adhered due to large specific surface area and strong hydrophobic effect, or because of the wrapping barrier effect of the endosperm cell wall. In summary, the use of buckwheat core flour processed by roller milling technology to make fried instant noodles has the feasibility of reducing the oil content. In addition, compared with whole buckwheat flour, buckwheat meal and buckwheat bran, buckwheat core flour has lower ash and fat content, which is conducive to preventing oil rancidity and oxidation and ensuring the shelf life of the product. Summary of the invention:

[0005] The purpose of the present invention is to provide a method for processing low-fat fried buckwheat instant noodles. The specific implementation scheme of the technical scheme of the present invention is as follows: wheat flour, buckwheat core flour, auxiliary materials and water are mixed for 5 to 30 minutes to form a dough, and the dough is proofed for 5 to 60 minutes at a temperature of 20 to 40° C., molded, steamed for 1.5 to 7 minutes at 0.1 to 0.2 MPa, and fried at 140 to 160° C. for 40 to 120 seconds;

[0006] In one or more embodiments, the mass of the buckwheat core flour is 5-50%, preferably 5-25%, of the total mass of the wheat flour and buckwheat core flour; the amount of water added is 28-40%, preferably 34%, of the total mass of the wheat flour and buckwheat core flour.

[0007] In one or more embodiments, the buckwheat heart flour comprises unmodified or heat-modified buckwheat heart flour, rich in starch aggregates (naked starch, intact endosperm cells and fragments thereof), and has a particle size range of D 10 In 4~10μm, D 50 In 20~35μm, D 90 At 60~90μm.

[0008] In one or more embodiments, the buckwheat core flour is heat-modified buckwheat core flour, which is prepared by baking or steaming the unmodified buckwheat core flour as a raw material. The heat modification treatment can reduce the rehydration time of instant noodles and improve the overall texture quality.

[0009] In one or more embodiments, the auxiliary material includes a thickener, and the thickener includes one or more of xanthan gum, guar gum, sodium alginate, sodium carboxymethyl cellulose, and hydroxypropyl methylcellulose.

[0010] In one or more embodiments, the percentage of the thickener in the total mass of the wheat flour and buckwheat core flour is 0.2-1.0%, preferably 0.2-0.5%.

[0011] In one or more embodiments, the auxiliary material includes gluten powder accounting for 1-6% of the total weight of the wheat flour and buckwheat core flour.

[0012] The present invention also includes fried buckwheat instant noodles prepared by the method.

[0013] The beneficial effects of the present invention are:

[0014] The method for reducing the oil content of instant noodles provided by the invention ensures that the fried instant noodles not only have a lower oil content but also have good elasticity and chewiness.

[0015] The method for reducing the oil content of instant noodles provided by the invention is simple to operate and easy to realize industrial production. Description of the drawings:

[0016] Figure 1 The microstructure of buckwheat core flour contains a complete cell structure.

[0017] Figure 2 The microstructure of buckwheat flour with damaged cell structure.

[0018] Figure 3 This is the laser confocal scanning image of Example 3.

[0019] Figure 4 This is the laser confocal scanning image of Comparative Example 1.

[0020] Figure 5 This is the appearance of the fried instant noodles without adding buckwheat core flour in Comparative Example 1.

[0021] Figure 6 The appearance of fried instant noodles with 15% unmodified buckwheat flour added as in Example 3.

[0022] Figure 1 The red arrows in the middle are exposed starch clusters of different sizes, and the green arrows are complete endosperm cells. Figure 2The yellow arrows in the middle are scattered naked buckwheat starch clusters, and the red arrows are cell fragments. Figure 3 and Figure 4 The medium green color represents starch granules; the red color represents oil granules; and the blue color represents the gluten network structure. Specific implementation method:

[0023] It should be understood that within the scope of the present invention, the above-mentioned technical features of the present invention and the technical features specifically described below (such as embodiments) can be combined with each other to form a preferred technical solution.

[0024] Fried instant noodles are instant dry noodles that are steamed and then dehydrated to 4-8% by high-temperature frying process. The obtained noodles have a porous structure, good rehydration and good flavor. During the steaming and frying process, water vapor migrates in the noodles, causing the starch granules to swell and gelatinize. During the frying and cold cutting process, the gelatinized starch absorbs a large amount of oil, resulting in a high oil content in the fried instant noodles. The present invention adds buckwheat core flour rich in fine granular starch aggregate structure. On the one hand, the exposed starch clusters in the starch aggregates, due to the tight internal bonding, prevent the starch granules from adsorbing and penetrating oil during frying; on the other hand, the cell walls of the intact endosperm cells can block the entry of oil; in addition, after the starch aggregate structure is destroyed, the small-sized buckwheat starch fills the pores in the gluten network, hindering the diffusion of oil. Therefore, the addition of buckwheat core flour can reduce the oil content in fried instant noodles.

[0025] Specifically, the method for reducing the oil content of fried buckwheat instant noodles of the present invention comprises the steps of mixing wheat flour, buckwheat core flour, auxiliary materials and water into a dough, proofing, shaping, steaming and frying.

[0026] The flour described in the present invention is mainly wheat flour, and the wheat flour is a wheat flour product with different processing precision obtained by wheat milling process, with ash content of 0.3-1.2%, protein content of 8-15%, and wet gluten content of 26-36%. Preferably, in order to ensure better quality of instant noodles, the ash content is 0.4-0.7%, the protein content is 10-13%, and the wet gluten content is 28-34%.

[0027] The buckwheat core flour of the present invention can be buckwheat core flour obtained by roller milling buckwheat grains, or can be heat-modified buckwheat core flour obtained by baking the buckwheat core flour at 120-140° C. for 30-180 min, or steaming the buckwheat core flour at 98-100° C. for 30-180 min. 10 In 4~10μm, D 50 In 20~35μm, D 90The particle size is 60-90 μm, the protein content is 3-9%, the starch content is 75-90%, the dietary fiber content is less than 1.5%, and the ash content is less than 1%. The moisture content of the raw material of buckwheat core powder used for baking is 13%, and the moisture content of the raw material of buckwheat core powder used for steaming is 20-40%.

[0028] The auxiliary materials of the present invention include thickener and gluten powder.

[0029] The thickener of the present invention can be various polysaccharide thickeners without special restrictions; preferably, it includes one or more of xanthan gum, guar gum, sodium alginate, sodium carboxymethyl cellulose, and hydroxypropyl methylcellulose. The percentage of the thickener in the total mass of the wheat flour and buckwheat core flour is 0.2-1.0%, preferably 0.2-0.5%.

[0030] The auxiliary material of the invention comprises gluten powder accounting for 1-6% of the total weight of the wheat flour and buckwheat core powder.

[0031] The water used in the present invention is clean water from various sources that meets the requirements of the food industry. The added amount is generally 28-40% of the total mass of the wheat flour and the buckwheat core flour. If the added amount is too low, the dough cannot be formed during stirring. If the added amount is too high, the formed dough is too sticky, which affects the calendering operation of noodle processing and increases the load of frying and dehydration.

[0032] The dough described in the present invention is prepared from wheat flour and buckwheat flour as main raw materials, with thickener, gluten and other auxiliary materials added, and then a proper amount of water is added, and a flocculent dough with certain viscoelasticity is formed through the mechanical stirring action of a dough mixer. The mixing time is usually 5 to 30 minutes according to the rotating speed of the dough mixer. If the mixing time is too short, there will be more large dough pieces, less small dough particles, uneven particle size and poor noodle quality. If the mixing time is too long, the dough strength will be reduced, which will also cause the noodle quality to decline.

[0033] The proofing described in the present invention is also often called maturation in industry. It is a common process for processing noodle products. Its main function is to promote dough hydration and gluten network development and release the stress formed in the dough by mechanical equipment during the mixing process. It can be carried out by using equipment such as a disc maturator and a belt maturator. There are static proofing, low-speed stirring proofing and other methods. The proofing temperature is 20-40°C and the proofing time is 5-60min. Too low and too high temperature and time are not conducive to the development of the gluten network.

[0034] The present invention also found that even without the proofing process, the noodles can still be well formed in the subsequent calendering process and made into instant noodles after frying, but the gluten network in the noodles is not developed enough, resulting in insufficient elasticity and chewiness of the noodles, and the instant noodles will have a high oil content and increased rehydration time. Therefore, the process without dough proofing is not an industrially preferred solution. The forming described in the present invention, in terms of instant noodle production, includes processes such as calendering, strip cutting, and folding. The calendering generally includes two stages, composite calendering and continuous calendering. The gluten structure inside the dough after proofing is relatively loose. The calendering process allows the dough to form a dense, mutually bonded gluten tissue under continuous external force compression. At the same time, the gluten network produces regular directionality, has strong tensile properties and rheological properties in the longitudinal direction, and makes the dough roll through multiple calendering rollers to make it into a thin sheet that meets the requirements, which is conducive to subsequent processing. The calendered thin noodles are cut into required strips such as round, square or oval by a noodle cutter. In order to prevent noodles from sticking to each other during steaming and to speed up the evaporation of water during dehydration, instant noodles are cut into strips and then folded into a special shape of waves with vertical peaks, front and back peaks close to each other, continuous and undulating. In addition, after the instant noodles are formed by calendering, the noodles can be left to rise for a period of time, which is 10 to 15 minutes. Although the rising of the noodles is not necessary for the production of instant noodles, proper rising of the noodles can improve the quality of the noodles.

[0035] The steaming method described in the present invention is to treat noodles with saturated steam so that starch is gelatinized and protein is denatured by heat, and raw noodles are made into cooked noodles. The degree of starch gelatinization (also called α-denaturation) of the noodles should be above 80%. The steaming time is 4 to 7 minutes at a steam pressure of 0.1 to 0.15 MPa. When a higher steam pressure, such as 0.15 to 0.2 MPa, is used, the required steaming time can be shortened to 1.5 to 4 minutes.

[0036] The frying process described in the present invention is a typical dehydration process. The noodle block is placed in an oil tank, surrounded by high-temperature oil, and the water in the noodles is rapidly vaporized and escaped, forming fried instant noodles with a large number of microporous structures, good rehydration performance, and a high degree of α-ization. The frying temperature is 145-160° C. and the frying time is 40-120 seconds.

[0037] After frying and dehydration, the temperature of instant noodles is relatively high. When they are sent to the cooler, the temperature is generally still around 80℃~100℃, and they need to be cooled before they can be packaged. The cooling of instant noodles is carried out in the cooler. After about 3~4 minutes of cooling, the noodle block temperature drops to room temperature ±5℃ before packaging.

[0038] The fried instant noodles prepared by the method described herein are also included in the scope of the present invention. Preferably, the fried instant noodles have an oil content of 14-16%, and have moderate hardness, good elasticity, good chewiness, and short rehydration time.

[0039] The present invention has the following advantages:

[0040] The fried instant noodle processing method provided by the invention can not only enable the sample to obtain a low oil content, but also enhance the edible qualities of the sample, such as rehydration, elasticity, chewiness and the like.

[0041] The method for reducing the oil content of instant noodles provided by the invention is simple to operate and easy to realize industrial production.

[0042] In the fried instant noodle processing method provided by the present invention, the addition of buckwheat core flour rich in starch aggregate structure enhances the anti-digestion components in the instant noodles and brings a unique buckwheat flavor, thereby reducing the oil content and increasing the quality of the noodles. Specific implementation method:

[0044] The present invention will be described below in the form of specific examples. It should be understood that these examples are merely illustrative and are not intended to limit the scope of the present invention. The main raw material wheat flour used in the examples is a special flour for the production of instant noodles. The buckwheat core flour used in the examples is buckwheat core flour made by a 3-skin 4-core roller milling process after shelling the sweet buckwheat seeds. The equipment for particle size measurement comes from Dandong Better Technology Co., Ltd. The equipment used for dough mixing and pressing comes from Beijing Dongfang Fude Technology Development Center, and the equipment used for steaming comes from Henan Dongfang Noodle Machine Group Co., Ltd. The frying equipment comes from Guangzhou Tuoqi Kitchen Equipment Co., Ltd. Unless otherwise stated, the other methods used in the examples are conventional methods in the art.

[0045] Examples 1 to 8, Comparative Example 1

[0046] Raw materials were prepared, the wheat flour of Examples 1 to 8 were 95, 90, 85, 80, 75, 70, 60, and 50 g, the unmodified buckwheat core powder was 5, 10, 15, 20, 25, 30, 40, and 50 g, and the total mass of the wheat flour and buckwheat core powder was 100 g. Comparative Example 1 did not add buckwheat core powder.

[0047] Prepare auxiliary materials, based on the total mass of the raw materials, 2% gluten powder, 1% edible salt, and 34% water.

[0048] The raw materials and auxiliary materials are kneaded into dough at room temperature for 10 minutes, proofed at 25°C for 30 minutes, rolled, cut into strips, folded, steamed for 5 minutes at a steam pressure of 0.15 MPa, cooled to room temperature, and fried at 150°C for 120 seconds.

[0049] Test Example 1

[0050] The instant noodles prepared in Examples 1 to 8 and Comparative Example 1 were tested and calculated for oil content, oil content reduction rate, rehydration time, and texture characteristics.

[0051] Oil content and percentage reduction of oil content: The oil absorption rate of the present invention is detected by Soxhlet extraction method according to the first method of GB 5009.6-2016. Percentage reduction of oil content (%) = (oil content of fried noodles with added buckwheat core flour - oil content of fried noodles without added buckwheat core flour) / oil content of fried noodles without added buckwheat core flour × 100%.

[0052] Rehydration time: Fried instant noodles are divided into instant noodles, dry noodles and boiled noodles, and the rehydration time requirements are all different. In order to more comprehensively evaluate the rehydration time of fried instant noodles, the present invention adopts two common methods for determination. The first is the boiling noodle method. Take 1 portion of the noodles prepared in the embodiment and place them in boiling water. Keep the water at a slightly boiling state of 98-100°C. Take out a noodle every 5 seconds from the beginning. After drying, flatten it with two glass sheets, observe the white hard core line inside the noodles, and the time recorded when the white hard core line disappears is the optimal rehydration time. Set 3 repetitions. The second is the instant noodle method, which is carried out according to the rehydration time determination method in GB / T 40722-2021 instant noodles.

[0053] Water absorption rate and cooking loss rate: Take 50g of instant noodles, cook the instant noodles to the optimal rehydration time according to the method for determining the rehydration time, place the noodles on filter paper, and weigh accurately after 5 minutes. Water absorption rate of instant noodles = (weight after rehydration - weight before rehydration) / weight before rehydration × 100%; transfer the noodle soup after the noodles are taken out to a pre-weighed beaker, heat with an electric furnace to evaporate to 100mL, and then put it in an oven at 105℃ to dry to constant weight. The cooking loss rate of instant noodles = (weight of beaker after drying - initial weight of beaker) / weight of instant noodles before cooking × 100%.

[0054] Texture characteristics: Place the instant noodles in slightly boiling water and cook until the optimal rehydration time, remove from the supercooled water for 30 seconds, place in a tray covered with wet gauze, and cover with wet gauze to prevent water evaporation. Use TA.XT Plus texture analyzer for texture measurement, and select HDP / PFS as the probe model for texture curve analysis (TPA) experiment. Test parameters: pre-measurement speed: 2.0mm / s; measurement speed: 0.8mm / s; post-measurement speed: 2.0mm / s; downward pressure 70%; starting point induction force: 5g; time interval between two compressions: 2s. Each sample is measured at least 7 times. Obtain indicators such as hardness, adhesion, cohesion, elasticity, chewiness, and recovery.

[0055] The test results are shown in Table 1.

[0056] As can be seen from Table 1, with the increase in the amount of buckwheat core powder added, the oil content and rehydration time of the instant noodles gradually decreased, the water absorption rate and cooking loss rate gradually increased, the hardness and chewiness gradually increased, and the elasticity first increased and then decreased. In addition, the appearance of the instant noodles did not change significantly after adding buckwheat core powder. Compared with Comparative Example 1 ( Figure 5 ), after adding 15% buckwheat flour, the instant noodles still maintain good color ( Figure 6 After adding buckwheat flour, starch aggregates were observed in fried instant noodles ( Figure 3 The yellow arrow in the figure shows the characteristic structure, while the instant noodles without buckwheat flour do not have this characteristic structure ( Figure 4 ). And it can be observed that there is very little distribution of oil in the structure ( Figure 3 Red area). As the amount of buckwheat core flour added increases, the oil content of instant noodles is greatly reduced, but the hardness of Examples 4 and 5 is too large and has a high cooking loss rate. Therefore, the instant noodles obtained in Example 3 have better edible quality.

[0057] Table 1 Effect of different amounts of buckwheat flour added on the quality of instant noodles

[0058]

[0059]

[0060] *Comparative Example 1 does not add buckwheat core powder, and other processes are consistent with Example 1.

[0061] **The rehydration time is the result of method one and method two respectively, the same below.

[0062] Examples 9 to 12

[0063] Prepare raw materials, 85g wheat flour, 15g buckwheat core powder. The buckwheat core powder is obtained by 3B-4M-1S roller milling process according to the method and milling and mixing process parameters described in (Izydorczyk MS, Head D. Characterization and potential uses of functional buckwheat fractions obtained by roller milling of new Canadian buckwheat genotypes [J]. Eur. J. Plant Sci. Biotechnol, 2010, 4: 71-81.). The buckwheat core powder in Examples 9 and 10 is made from shelled sweet buckwheat grains (Jin buckwheat (sweet) No. 1), and Example 10 is baked at 130° C. for 2 h; the buckwheat core powder in Example 11 is made from shelled tartary buckwheat (Siberian tartary buckwheat) and is baked at 130° C. for 3 h; the buckwheat core powder in Example 12 is made from shelled tartary buckwheat (Sui Tianluo tartary buckwheat) and the water content is adjusted to 35% before steaming for 30 min; the basic components and particle size of the buckwheat core powder used in Examples 9 to 12 are shown in Table 2.

[0064] Prepare auxiliary materials, based on the total mass of the raw materials, 2% gluten powder, 1% edible salt, and 34% water.

[0065] The raw materials and the auxiliary materials are processed into fried instant noodles according to the processing method of Example 1.

[0066] Test Example 2

[0067] The protein content of buckwheat core flour is determined according to the first method of GB 5009.5-2016 National Food Safety Standard Determination of Protein in Food.

[0068] The starch content of buckwheat core flour is determined by polarimetry according to GB / T 20378-2006 Determination of starch content of native starch.

[0069] Ash content of buckwheat core flour: Determined according to the first method in GB 5009.4-2016 National Food Safety Standard Determination of Ash in Food.

[0070] Dietary fiber content of buckwheat core flour: according to the method for determination of dietary fiber in food of GB 5009.88-2014 National Food Safety Standard.

[0071] Buckwheat core powder particle size distribution: The laser particle size distribution instrument is used for measurement. The sample is added to the sample dispersion pool to ensure that the sample shading rate is not higher than 12%. After ultrasonic dispersion for 40 seconds, the test is carried out in continuous mode to obtain the particle size distribution curve. D10: It means that in the sample, 10% of the particles have a particle size smaller than this value, which means that the particles below this value account for 10% of the total sample. This indicator is used to characterize the fine particle part in the powder. D50: Also known as the median particle size, it means that 50% of the particles in the sample have a particle size smaller than this value, and the particle size of the other half of the particles is larger than this value. D50 is a typical value for measuring the particle size of powders and is usually used as the average particle size of powders. D90: It means that in the sample, 90% of the particles have a particle size smaller than this value. The D90 value is usually used to evaluate the coarse particle part in the powder and is widely used in powder production and application fields, especially in the production process, where the coarse particle content needs to be controlled to ensure product quality.

[0072] The instant noodles prepared in Examples 9 to 12 were tested and calculated for oil content, oil reduction rate, rehydration time, and texture characteristics. The specific methods were carried out with reference to Test Example 1.

[0073] The test results are shown in Table 3.

[0074] As can be seen from Table 2, the particle size and basic components of buckwheat core powder of different varieties of buckwheat grains under various grinding accuracies and splitting modes are different. In particular, the particle size contains only a small amount of buckwheat starch fine particles (<10 μm only accounts for 10%), and most of them exist in the form of aggregates. However, as can be seen from Table 3, the addition of different buckwheat core powders can reduce the oil content of instant noodles and reduce the rehydration time. In terms of comprehensive texture quality, Example 11 is the best.

[0075] Table 2 Basic components and particle size distribution of buckwheat core powder used in different embodiments

[0076] sample Crude protein / % Crude starch / % Ash / % Total dietary fiber / % <![CDATA[D 10 / μm]]> <![CDATA[D 50 / μm]]> <![CDATA[D 90 / μm]]> Example 9 3.66 89.79 0.45 0.88 4.06 21.57 60.7 Example 10 5.83 80.32 0.56 0.87 7.35 25.71 70.44 Embodiment 11 7.35 79.88 0.41 0.75 8.37 30.34 79.04 Example 12 9.23 75.25 0.77 1.49 9.98 35.11 90.01

[0077] Table 3 Effect of adding different buckwheat flour on the quality of fried instant noodles

[0078]

[0079]

[0080] Examples 13 to 21

[0081] Prepare raw materials, 85g of wheat flour. In Examples 13 to 15, 15g of heat-modified buckwheat core flour baked at 120°C for 1h, 2h and 3h were added respectively; in Examples 16 to 18, 15g of heat-modified buckwheat core flour baked at 130°C for 1h, 2h and 3h were added respectively; in Examples 19 to 21, 15g of heat-modified buckwheat core flour baked at 140°C for 1h, 2h and 3h were added respectively.

[0082] Prepare auxiliary materials, based on the total mass of the raw materials, 2% gluten powder, 1% edible salt, and 34% water.

[0083] The raw materials and the auxiliary materials are processed into fried instant noodles according to the processing method of Example 1.

[0084] Test Example 3

[0085] The instant noodles prepared in Examples 13 to 21 and the control instant noodles were tested and calculated for oil content, oil content reduction rate, rehydration time, and texture characteristics. The specific method is based on Test Example 1.

[0086] The test results are shown in Table 4.

[0087] As can be seen from Table 4, the addition of heat-modified buckwheat core flour after baking can still reduce the oil content of fried instant noodles, among which the heat-modified buckwheat core flour baked at 120°C has a better oil reduction effect. At the same time, the addition of heat-modified buckwheat core flour greatly shortens the rehydration time of instant noodles, and with the increase of baking temperature and the increase of baking time, the rehydration time of instant noodles decreases accordingly. In addition, the effect of the heat-modified conditions of buckwheat core flour on the texture characteristics of instant noodles is manifested in that the hardness of instant noodles increases, the elasticity decreases, and the chewiness decreases under high temperature and long-term baking. Therefore, Example 9 has the best effect on improving the quality of instant noodles.

[0088] Table 4 Effect of adding roasted heat-modified buckwheat core flour on the quality of instant noodles

[0089]

[0090]

[0091] *Comparative Example 1 does not add buckwheat core powder, and other processes are consistent with Example 6.

[0092] Embodiments 22 to 24

[0093] Prepare raw materials, 85g of wheat flour, and add 15g of heat-modified buckwheat core powder obtained by steaming in Examples 22 to 24 respectively. The specific processing methods are as follows: the heat-modified buckwheat core powder used in Example 22 is obtained by adjusting the moisture content to 15% and steaming at 100°C for 30 minutes; Example 23 is obtained by adjusting the moisture content to 25% and steaming at 100°C for 30 minutes; Example 24 is obtained by adjusting the moisture content to 35% and steaming at 100°C for 30 minutes.

[0094] Prepare auxiliary materials, based on the total mass of the raw materials, 2% gluten powder, 1% edible salt, and 34% water.

[0095] The raw materials and the auxiliary materials are processed into fried instant noodles according to the processing method of Example 1.

[0096] Test Example 4

[0097] The instant noodles prepared in Examples 22 to 24 and the control instant noodles were tested and calculated for oil content, oil content reduction rate, rehydration time, and texture characteristics. The specific methods were carried out with reference to Test Example 1.

[0098] The test results are shown in Table 5.

[0099] As can be seen from Table 5, the oil content of instant noodles is reduced after adding steam-heat-modified buckwheat core flour, and the modified buckwheat flour obtained by adjusting the moisture content of buckwheat core flour to 35% and steaming at 100°C for 30 minutes has a very obvious oil reduction effect. In addition, the addition of steam-modified buckwheat core flour reduces the rehydration time of instant noodles and increases the hardness of instant noodles. Example 23 significantly reduces the oil content while maintaining the quality of instant noodles. Compared with Example 3, the oil reduction effect is better and more obvious, and the quality of instant noodles does not decrease to a large extent.

[0100] Table 5 Effect of adding steamed heat-modified buckwheat core flour on the quality of instant noodles

[0101]

[0102] *Comparative Example 1 does not add buckwheat core powder, and other processes are consistent with Example 17.

[0103] Examples 25 to 29, Comparative Example 2.

[0104] Prepare the raw materials: 85g wheat flour and 15g unmodified buckwheat core flour.

[0105] Prepare auxiliary materials, based on the total mass of the raw materials, 1% edible salt and 34% water, and the gluten powder in Examples 25 to 29 is added according to Table 6.

[0106] The raw materials and the auxiliary materials are kneaded into dough at room temperature for 10 minutes, proofed at 25°C for 30 minutes, sliced ​​and cut into strips, steamed at a steam pressure of 0.15 MPa for 5 minutes, cooled to room temperature, and fried at 150°C for 120 seconds.

[0107] Table 6 Addition amount of gluten in different embodiments

[0108]

[0109]

[0110] Test Example 5

[0111] The instant noodles prepared in Examples 25 to 29 and the control instant noodles were tested and calculated for oil content, rehydration time and texture characteristics.

[0112] The test results are shown in Table 7.

[0113] As can be seen from Table 7, with the increase of the amount of gluten added, the rehydration time of the instant noodles showed a trend of first increasing and then decreasing. When the amount of gluten added was 2% (Example 3), the instant noodles showed good rehydration and moderate hardness.

[0114] Table 7 Effect of different gluten addition amounts on instant noodles quality

[0115] sample Comparative Example 1 Comparative Example 2 Embodiment 25 Example 3 Oil content / % 16.12 14.97 14.33 14.31 Rehydration time / s 250.00 240.33 275.00 243.98 Hardness / g 3151.34 2988.76 3131.99 3352.50 sample Embodiment 26 Embodiment 27 Embodiment 28 Embodiment 29 Oil content / % 14.23 14.18 14.11 13.09 Rehydration time / s 297.00 321.33 340.00 345.33 Hardness / g 3459.72 3451.41 3531.42 3561.66

[0116] *Comparative Example 2 did not add buckwheat core powder, and other processes were consistent with Example 2.

[0117] **Rehydration time is the result of method 2.

[0118] Examples 30 to 38, Comparative Example 3

[0119] Prepare the raw materials: 85g wheat flour and 15g unmodified buckwheat core flour.

[0120] Prepare auxiliary materials, based on the total mass of the raw materials, 2% gluten, 1% edible salt, and 34% water. Examples 30 to 38 respectively add 0.2% xanthan gum, 0.2% guar gum, 0.2% guar gum and xanthan gum (1:1), 0.2% sodium alginate, 0.2% sodium carboxymethyl cellulose, 0.2% hydroxypropyl methylcellulose, 0.3% hydroxypropyl methylcellulose, 0.4% hydroxypropyl methylcellulose, and 0.5% hydroxypropyl methylcellulose, and the comparative example does not add a thickener.

[0121] The raw materials and the auxiliary materials are kneaded into dough at room temperature for 10 minutes, proofed at 25°C for 30 minutes, sliced ​​and cut into strips, steamed at a steam pressure of 0.15 MPa for 5 minutes, cooled to room temperature, and fried at 150°C for 120 seconds.

[0122] Test Example 6

[0123] The instant noodles prepared in Examples 30 to 38 and the control instant noodles were tested and calculated for oil content, oil content reduction rate, rehydration time, and texture characteristics.

[0124] The test results are shown in Table 8.

[0125] As can be seen from Table 8, instant noodles prepared with different thickeners and different addition amounts can reduce the oil content of the instant noodles and increase the elasticity and chewiness of the instant noodles, but Example 27 has the best oil reduction effect, rehydration time and elasticity.

[0126] Table 8 Effects of different thickener addition amounts on instant noodles quality

[0127]

[0128]

[0129] *Comparative Example 1 does not add buckwheat core powder, and Comparative Example 3 does not add thickener. Other processes are consistent with Example 25.

[0130] **Rehydration time is the result of method 1 and method 2.

[0131] Embodiments 39 to 51

[0132] Prepare the raw materials: 85g wheat flour and 15g unmodified buckwheat core flour.

[0133] Prepare auxiliary materials, based on the total mass of the raw materials, 2% gluten powder, 1% edible salt, and 34% water.

[0134] The raw materials, the auxiliary materials and the dough are kneaded, proofed, formed, steamed and fried. The specific process conditions of kneading, proofing, steaming and frying are shown in Table 9.

[0135] Table 9 Main process parameters of instant noodles production process

[0136]

[0137] Test Example 7

[0138] The instant noodles prepared in Examples 39 to 51 and the control instant noodles were tested and calculated for oil content, rehydration time and texture characteristics.

[0139] The test results are shown in Table 10.

[0140] As can be seen from Table 10, considering the comprehensive oil content, rehydration and elasticity, the kneading time is 5 to 30 minutes, and the best is 10 minutes; the proofing temperature is 20 to 40°C, and the best is room temperature 25°C; the proofing time is 5 to 60 minutes, and the best is 30 minutes; the steaming pressure is 0.1-0.2MPa, and the time is 1.5 to 7min, and the best is 0.15MPa, 5min; the frying temperature is 140 to 160°C, and the frying time is 40 to 120s, and the best is 120s at 150°C, which has a better effect.

[0141] Table 10 Effects of different steaming and frying process parameters on instant noodles quality

[0142] sample Embodiment 39 Embodiment 40 Embodiment 41 Embodiment 42 Embodiment 43 Embodiment 44 Embodiment 45 Oil content / % 15.26 14.51 15.20 14.80 14.38 14.89 14.31 Rehydration time / s 301.00 256.00 231.32 313.33 249.33 288.00 453.00 Elasticity / s 0.75 0.88 0.89 0.75 0.89 0.80 0.88 sample Embodiment 46 Example 3 Embodiment 47 Embodiment 48 Embodiment 49 Embodiment 50 Embodiment 51 Oil content / % 16.8 14.31 14.56 15.13 15.22 15.55 15.78 Rehydration time / s 318.00s 243.98 248.00 310.00 350.33 518.00 230.33 Elasticity / s 0.85 0.98 0.97 0.91 0.76 0.77 0.75

[0143] *Rehydration time is the result of method 2.

[0144] The above description is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by a person of ordinary skill in the art without departing from the concept and principle of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A method for processing low-oil-content buckwheat fried instant noodles, characterized in that: The method comprises the following steps: Mix wheat flour, buckwheat flour, auxiliary materials and water for 5-30 min to form a dough, let it rise at 20-40 °C for 5-60 min, shape it, steam it at 0.1-0.2 MP for 1.5-7 min, and fry it at 140-160 °C for 40-120 s. The mass of the buckwheat core powder is 5-50% of the mass of the wheat flour, and the added amount of water is 28-40% of the total mass of the wheat flour and the buckwheat core powder.

2. The method according to claim 1, characterized in that The unmodified buckwheat core flour is a product rich in starch aggregates obtained by separating the cortex through a roller milling process. The particle size range of the buckwheat core flour is 4-10 μm for D10, 20-35 μm for D50, and 60-90 μm for D90; its protein content is 3-9%, the starch content is 75-90%, the dietary fiber content is less than 1.5%, and the ash content is less than 1%.

3. The method according to claim 1, characterized in that The buckwheat core flour is heat-modified buckwheat core flour obtained by baking or steaming.

4. The method according to claim 3, characterized in that The buckwheat core powder baking treatment is a dry heat treatment at 120-140°C for 30-180 min, and the steaming treatment is a wet heat treatment at 98-100°C for 30-180 min; the moisture content of the unmodified buckwheat core powder after the baking treatment is 13%, and the moisture content of the unmodified buckwheat core powder after the steaming treatment is 20-40%.

5. The method according to claim 4, characterized in that The degree of gelatinization of the baked buckwheat core flour is 5-30%, and the degree of gelatinization of the steamed buckwheat core flour is 30-80%.

6. The method according to claim 4, characterized in that The baked modified buckwheat core flour is prepared by baking at 120°C, and the steamed modified buckwheat core flour is prepared by adjusting the moisture content of the unmodified buckwheat core flour to 35% and then steaming at 100°C for 30 minutes.

7. The method according to claim 1, characterized in that The auxiliary materials include a thickener, which includes one or more of xanthan gum, guar gum, locust bean gum, sodium alginate, sodium carboxymethyl cellulose, and hydroxypropyl methylcellulose. The added amount of the thickener is 0.2-1.0% of the total mass of the wheat flour and buckwheat core flour.

8. The method according to claim 1, characterized in that The auxiliary material includes gluten powder accounting for 1-6% of the total mass of the wheat flour and buckwheat core powder.

9. The method according to claim 1, characterized in that: The amount of water added is 34% of the total mass of the wheat flour and buckwheat core flour.

10. Buckwheat fried instant noodles prepared according to the method according to any one of claims 1 to 9.

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