Preparation method of low-gi non-fried Hong Kong style cheung zei noodles

Abstract

The application discloses a preparation method of low-GI non-fried Hong-style vehicle noodles, and relates to the technical field of noodle processing. The application is used for solving the problems of low content of low-GI grain protein, weak gluten network and low efficiency of traditional enzymatic cross-linking reaction by means of transglutaminase cross-linking combined with low-frequency ultrasonic auxiliary technology. The cavitation effect generated by low-frequency ultrasonic can increase the contact area of transglutaminase and protein substrate, accelerate the enzymatic reaction process, and improve the degree of protein cross-linking, so that a dense and uniform three-dimensional protein network structure is formed. The network can tightly wrap starch granules, limit the swelling and gelatinization of the starch granules, significantly improve the boiling resistance of the noodles, reduce the noodle breaking rate, delay the contact between amylase and starch, preliminarily reduce the starch digestion rate, and lay a foundation for further reducing the GI value.

Description

Technical Field

[0001] This invention relates to the field of noodle product processing technology, specifically a method for preparing low-GI non-fried Hong Kong-style cart noodles. Background Technology

[0002] Hong Kong-style cart noodles are popular among consumers for their smooth texture and convenience. However, traditional cart noodles are often deep-fried, resulting in a high fat content. Furthermore, the starch in refined wheat flour is rapidly digested in the body, leading to a high glycemic index (GI), which is unsuitable for long-term consumption by people with diabetes or those trying to control their blood sugar.

[0003] To reduce the glycemic index (GI), current low-GI noodle products are mostly made by blending low-GI grains such as buckwheat and mung beans with wheat flour. However, low-GI grains have low protein content and weak gluten network structure, resulting in noodles with poor cooking resistance, prone to cloudy broth and breakage, and unable to retain the typical texture of Hong Kong-style cart noodles. Single protein cross-linking technology can only improve texture to a limited extent and cannot effectively delay starch digestion; single starch modification technology easily damages the dough network, leading to a deterioration in taste. At the same time, existing enzymatic cross-linking technologies have low reaction efficiency and insufficient protein cross-linking degree. Starch esterification modification lacks effective auxiliary means, resulting in a low degree of reaction and an inability to form a stable, digestibility-resistant structure, making it difficult to simultaneously achieve texture improvement and a significant reduction in GI.

[0004] Therefore, there is an urgent need to develop a low-GI non-fried Hong Kong-style cart noodles preparation method that can significantly enhance protein cross-linking, simultaneously construct protein-starch covalent interpenetrating networks, and has good process compatibility. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a method for preparing low-GI non-fried Hong Kong-style cart noodles. This method utilizes transglutaminase cross-linking combined with low-frequency ultrasound-assisted technology to address the problems of low GI cereal protein content, weak gluten network, and low efficiency of traditional enzymatic cross-linking reactions. The cavitation effect generated by low-frequency ultrasound can increase the contact area between transglutaminase and the protein substrate, accelerate the enzymatic reaction process, improve the degree of protein cross-linking, and form a dense and uniform three-dimensional protein network structure. This network can tightly wrap starch granules, restrict the expansion and gelatinization of starch granules, significantly improve the noodle's resistance to overcooking, reduce the breakage rate, and delay the contact between amylase and starch, initially reducing the starch digestion rate and laying the foundation for further reducing the GI value.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for preparing low-GI non-fried Hong Kong-style cart noodles, wherein the specific steps of the method are as follows:

[0007] S100, Raw material compounding: Take low-GI grain flour, high-gluten wheat flour, soy protein isolate, edible salt, compound phosphate, and Hong Kong-style flavor improver. Mix the raw materials evenly and add drinking water at 35-40% of the total flour weight. Stir to obtain dough.

[0008] S200, Ultrasonic-assisted Enzymatic Protein Crosslinking: Transglutaminase is added to the dough obtained by S100, and enzymatic crosslinking reaction is carried out under low-frequency ultrasound to strengthen the three-dimensional protein network structure.

[0009] S300, Ultrasonic Synergistic pH Cycling Dual Crosslinking: Citric acid is added to the dough treated with S200, and a pH cycling process is used to simultaneously drive the protein crosslinking reaction catalyzed by transglutaminase and the esterification reaction of citric acid and starch hydroxyl groups to form a protein-starch covalent interpenetrating network.

[0010] S400, rolling and cutting: The dough treated by S300 is rolled multiple times until it reaches the preset thickness and then cut into strips to obtain the cart noodle raw dough;

[0011] S500, Non-fried Shaping and Drying: The cart noodle raw material obtained by S400 is steamed and shaped, and then dried with segmented hot air to the preset moisture content to obtain a low-GI non-fried Hong Kong-style cart noodle finished product.

[0012] Furthermore, in S100, the low-GI cereal powder is a mixture of buckwheat flour and mung bean flour in a mass ratio of 1:1. By weight, the amount of each ingredient added is as follows: 60-80 parts of low-GI cereal powder, 20-40 parts of high-gluten wheat flour, 8 parts of soy protein isolate, 1-2 parts of edible salt, 0.3-0.5 parts of compound phosphate, and 0.5-1 parts of Hong Kong-style flavor improver.

[0013] Furthermore, the composite phosphate is a mixture of sodium hexametaphosphate, sodium tripolyphosphate, and sodium pyrophosphate in a mass ratio of 45:27.5:27.5, used to improve the extensibility of dough.

[0014] Furthermore, the Hong Kong-style flavor improver is a mixture of maltodextrin, disodium inosinate, and spices in a mass ratio of 5:3:2, used to recreate the classic flavor of Hong Kong-style cart noodles.

[0015] Furthermore, in S200, the amount of transglutaminase added is 0.4 U / g protein;

[0016] The process parameters for the low-frequency ultrasound are: frequency 40kHz, power 50W, processing time 15 minutes, and reaction temperature maintained at 40-45℃.

[0017] The ultrasonic cavitation effect promotes full contact between transglutaminase and protein substrate, increases the degree of protein cross-linking, and forms a dense three-dimensional protein network that encapsulates starch granules.

[0018] Furthermore, in S300, the amount of citric acid added is 0.2%;

[0019] The pH cycling process is as follows: the pH value of the dough system is adjusted to 7.5, and then treated for 10 minutes under the same low-frequency ultrasonic conditions;

[0020] The pH of the system was lowered to 5.5 by introducing CO2 gas, and the reaction was continued for 5 minutes while maintaining the pH at 5.5.

[0021] Spray sodium carbonate solution to adjust the pH to 7.0 and continue sonication for 3 minutes;

[0022] Among them, pH 7.5 is the optimal reaction pH for transglutaminase, which can activate transglutaminase to continuously catalyze protein cross-linking; pH 5.5 is the optimal pH for the esterification reaction between citric acid and starch hydroxyl groups. The ultrasonic cavitation effect can promote the esterification reaction between citric acid and starch molecule hydroxyl groups. The two reactions proceed simultaneously, forming an interpenetrating protein-starch covalent interpenetrating network.

[0023] Furthermore, in S400, during the rolling process, the dough is allowed to rest and rise for 15-20 minutes, then rolled into a sheet with a thickness of 1-1.5mm using a rolling mill, and then cut into noodles with a width of 2-3mm using a strip cutter to obtain the raw dough for cart noodles.

[0024] Furthermore, in S500, the steaming and shaping process is as follows: the raw dough for cart noodles is placed in a steamer and steamed at 95-100℃ for 8-10 minutes until the noodles are fully cooked, avoiding overcooking which would cause starch gelatinization and loss. The temperature of the hot air drying is 65℃, and the preset moisture content is 10%-12%.

[0025] Furthermore, in S500, the segmented hot air drying process is as follows: the cooked noodles are sent into the hot air drying equipment, the first stage is dried at 60-70℃ for 30-40 minutes, the second stage is dried at 45-55℃ for 20-30 minutes, and the noodles are dried until the moisture content is 8-12%, thus obtaining the low-GI non-fried Hong Kong-style cart noodles.

[0026] Compared with existing technologies, this method for preparing low-GI non-fried Hong Kong-style cart noodles has the following advantages:

[0027] I. This invention utilizes transglutaminase cross-linking combined with low-frequency ultrasound-assisted technology to address the problems of low GI cereal protein content, weak gluten network, and low efficiency of traditional enzymatic cross-linking reactions. The cavitation effect generated by low-frequency ultrasound can increase the contact area between transglutaminase and the protein substrate, accelerate the enzymatic reaction process, improve the degree of protein cross-linking, and form a dense and uniform three-dimensional protein network structure. This network can tightly wrap starch granules, restrict the expansion and gelatinization of starch granules, significantly improve the cooking resistance of noodles, reduce the breakage rate, and at the same time delay the contact between amylase and starch, initially reducing the starch digestion rate, laying the foundation for further reduction of GI value.

[0028] II. This invention utilizes an ultrasound-assisted pH-cycle-driven dual crosslinking technology to simultaneously achieve protein crosslinking and starch esterification in the same reaction system, constructing a protein-starch covalently interpenetrating network. This overcomes the shortcomings of incompatible enzyme crosslinking and esterification reaction conditions and the single network structure. Citric acid is added during the ultrasound-assisted enzyme reaction, and a pH-cycle process is adopted to continuously generate cavitation effects during pH changes, causing the protein network and starch esterification network to interpenetrate and covalently connect at the molecular level, forming a protein-starch covalently interpenetrating dual network. This solves the problems of single network structure, low esterification efficiency, and incompatible reaction conditions in existing technologies.

[0029] Other advantages, objectives and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be learned from the practice of the invention. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0031] Figure 1 A flowchart illustrating the steps of a method for preparing low-GI non-fried Hong Kong-style cart noodles;

[0032] Figure 2 This is a flowchart illustrating a method for preparing low-GI non-fried Hong Kong-style cart noodles according to an embodiment of the present invention. Detailed Implementation

[0033] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0034] To address the issues of high fat content, high glycemic index (GI) of refined wheat flour in traditional Hong Kong-style cart noodles frying processes, and weak gluten development and difficulty in balancing texture and GI reduction effects when using low-GI grain blends, this invention provides a method for preparing low-GI non-fried Hong Kong-style cart noodles, as shown in Figure 1. The specific steps of this method are as follows:

[0035] S100, Raw material compounding: Take low-GI grain flour, high-gluten wheat flour, soy protein isolate, edible salt, compound phosphate, and Hong Kong-style flavor improver. Mix the raw materials evenly and add drinking water at 35-40% of the total flour weight. Stir to obtain dough.

[0036] S200, Ultrasonic-assisted Enzymatic Protein Crosslinking: Transglutaminase is added to the dough obtained by S100, and enzymatic crosslinking reaction is carried out under low-frequency ultrasound to strengthen the three-dimensional protein network structure.

[0037] S300, Ultrasonic Synergistic pH Cycling Dual Crosslinking: Citric acid is added to the dough treated with S200, and a pH cycling process is used to simultaneously drive the protein crosslinking reaction catalyzed by transglutaminase and the esterification reaction of citric acid and starch hydroxyl groups to form a protein-starch covalent interpenetrating network.

[0038] S400, rolling and cutting: The dough treated by S300 is rolled multiple times until it reaches the preset thickness and then cut into strips to obtain the cart noodle raw dough;

[0039] S500, Non-fried Shaping and Drying: The cart noodle raw material obtained by S400 is steamed and shaped, and then dried with segmented hot air to the preset moisture content to obtain a low-GI non-fried Hong Kong-style cart noodle finished product.

[0040] By employing ultrasound-assisted enzymatic protein cross-linking and ultrasound-coordinated pH cycling dual cross-linking technologies, the three-dimensional protein network is simultaneously strengthened and a protein-starch covalent interpenetrating network is constructed. Combined with non-fried steaming and segmented hot air drying processes, a low-GI non-fried Hong Kong-style cart noodle preparation scheme is formed that can significantly improve the noodle's resistance to boiling, restore the Hong Kong-style flavor, and effectively reduce the GI value, making it healthy and low-fat.

[0041] This invention is primarily applied to the industrial production of Hong Kong-style cart noodles in the noodle processing industry. Traditional fried cart noodles are high in fat and glycemic index (GI), making them unsuitable for people controlling their blood sugar. Existing low-GI noodle products suffer from defects such as easy clouding and breakage, low efficiency of enzymatic cross-linking, and insufficient esterification. Single protein cross-linking or starch modification technologies are difficult to reconcile with reaction conditions, failing to form a stable, digestibility-resistant structure. This invention achieves the dual goals of strengthening the dough network and delaying starch digestion by using low-frequency ultrasound-induced cross-linking with transglutaminase, pH cycling-driven simultaneous protein cross-linking and starch esterification, precise compounding of multi-component raw materials, and optimized steaming, shaping, and segmented hot air drying parameters. This results in low-GI, non-fried cart noodles that are resistant to boiling without breaking and have a smooth texture, meeting both health-conscious demands and large-scale production needs.

[0042] Unified performance testing method

[0043] To objectively, accurately, and reproducibly evaluate the overall performance of the low-GI non-fried Hong Kong-style cart noodles prepared in the various embodiments and comparative examples of this invention, and to eliminate the interference of differences in testing methods on the results, all samples were tested using a standardized method. Six parallel samples were set up for each test, and the results were taken as the arithmetic mean. The specific testing methods are as follows:

[0044] Texture determination: The texture analyzer was used in TPA mode. Test conditions: probe P / 36, pre-test speed 1 mm / s, test speed 1 mm / s, post-test speed 1 mm / s, compression ratio 50%, interval between two compressions 5 s, each sample was measured in parallel 6 times, and the average value was taken.

[0045] Breakage rate determination: Randomly select 50 noodles with a length of 20cm, put them into a beaker containing 1000mL of boiling water, keep them at a simmer and cook until the optimal eating time, gently remove them with a slotted spoon, and count the number of broken noodles. Breakage rate = number of broken noodles / 50 × 100%.

[0046] Cooking time test: Put 10 noodles into boiling water, take out one noodle every 1 minute, squeeze it with two glass plates, and observe whether there is a white core in the center of the noodle. The time until the white core completely disappears is the cooking time.

[0047] Turbidity determination: After cooking the noodles, the soup was cooled to room temperature, and the absorbance was measured at a wavelength of 600 nm using a UV-Vis spectrophotometer. The higher the absorbance value, the more turbid the soup.

[0048] In vitro GI value determination: The amount of glucose released within 0-120 min was measured using the Englyst in vitro simulated digestion method, and the hydrolysis index (HI) was calculated. The in vitro GI value was calculated according to the formula GI=0.862×HI+8.19.

[0049] Fat content determination: Soxhlet extraction method was used.

[0050] Example 1

[0051] This embodiment is used to verify the comprehensive performance of low-GI non-fried Hong Kong-style cart noodles prepared by combining 70 parts of low-GI cereal flour (blended with buckwheat flour and mung bean flour in a 1:1 mass ratio) and 30 parts of high-gluten wheat flour, combined with ultrasound-assisted transglutaminase crosslinking and ultrasound-assisted pH cycling dual crosslinking process. The performance of the noodles in terms of GI value, textural properties, cooking resistance and classic Hong Kong flavor is examined.

[0052] like Figure 2 As shown, the specific preparation steps of this method for preparing low-GI non-fried Hong Kong-style cart noodles are as follows:

[0053] S100, Ingredient Mixture: Weigh out 35 parts buckwheat flour, 35 parts mung bean flour, 30 parts high-gluten wheat flour, 8 parts soy protein isolate, 1.5 parts edible salt, 0.4 parts compound phosphate, and 0.75 parts Hong Kong-style flavor improver. Pour into a dough mixer and mix at low speed for 3 minutes until the dry powder is evenly mixed. The compound phosphate is composed of sodium hexametaphosphate, sodium tripolyphosphate, and sodium pyrophosphate in a mass ratio of 45:27.5:27.5. The Hong Kong-style flavor improver is composed of maltodextrin, disodium inosinate, and spices in a mass ratio of 5:3:2. Add drinking water (37.5% of the total powder weight) to the mixed dry powder and mix at low speed for 5 minutes until there are no lumps of dry powder. Then mix at high speed for 10 minutes to form a smooth and uniform dough.

[0054] S200, Ultrasonic-assisted enzymatic protein crosslinking: Transglutaminase is added to the above dough at a rate of 0.4 U / g protein. After stirring evenly, the mixture is transferred to a low-frequency ultrasonic reactor. The ultrasonic frequency is set to 40 kHz, the power to 50 W, and the temperature is kept constant at 42 ℃ for 15 min. The ultrasonic cavitation effect promotes full contact between transglutaminase and the protein substrate, thereby strengthening the three-dimensional network structure of the protein.

[0055] S300, Ultrasonic-Coordinated pH Cyclic Dual Crosslinking: Add 0.2% citric acid by mass to the treated dough and stir evenly; slowly adjust the pH of the dough system to 7.5 with 0.5 mol / L sodium carbonate solution, and maintain the same low-frequency ultrasonic conditions for 10 min to activate transglutaminase to continuously catalyze the protein crosslinking reaction; slowly introduce food-grade CO2 gas to lower the pH of the system to 5.5, maintain pH stability and continue ultrasonic reaction for 5 min to promote the esterification reaction between citric acid and starch hydroxyl groups; then spray 0.5 mol / L sodium carbonate solution to restore the pH to 7.0, and continue ultrasonication for 3 min to complete the construction of the protein-starch covalent interpenetrating network.

[0056] S400, Rolling and Cutting: The double cross-linked dough is placed at room temperature and allowed to rest for 18 minutes. It is then rolled 6 times through a rolling mill to finally form a uniform dough sheet with a thickness of 1.2 mm. The dough sheet is then cut into noodles with a width of 2.5 mm using a cutting machine to obtain the raw dough for cart noodles.

[0057] S500, Non-fried Shaping and Drying: Spread the raw cart noodles evenly on a steaming tray, place them in a steamer, and steam at 98℃ for 9 minutes until the noodles are fully cooked and there is no white core residue; then send the steamed noodles into a hot air drying device for segmented drying. The first segment is dried at 65℃ for 35 minutes, and the second segment is dried at 50℃ for 25 minutes, until the moisture content of the noodles is 10%. After cooling to room temperature, the low-GI non-fried Hong Kong-style cart noodles are obtained.

[0058] Performance test results: breakage rate 0.8%, boiling time 13 min, turbidity absorbance 0.052, hardness 4200g, elasticity 0.92, chewiness 3200g・s, in vitro GI value 53, fat content 0.7%, sensory score 92 points.

[0059] This embodiment successfully constructed a dense and uniform protein-starch covalent interpenetrating network through optimized raw material ratios and a complete double cross-linking process. This network not only tightly encapsulates starch granules, significantly improving the noodles' resistance to overcooking and their elasticity, resulting in an extremely low breakage rate and no obvious cloudiness in the broth, but also effectively slows down the starch digestion rate, making the product's GI value ≤55. By adding a special Hong Kong-style flavor improver, it perfectly reproduces the classic smooth texture and rich flavor of Hong Kong-style cart noodles, fully meeting the dual needs of people controlling their blood sugar for both health and taste.

[0060] Example 2

[0061] This embodiment is used to verify the GI value and texture balance performance of the cart noodles obtained by using the preparation process of the present invention when the addition amount of low GI cereal flour is 60 parts and high gluten wheat flour is 40 parts.

[0062] Preparation steps

[0063] The only difference from Example 1 is the raw material compounding step: 30 parts buckwheat flour, 30 parts mung bean flour, and 40 parts high-gluten wheat flour are weighed. The other types of raw materials, the amount added, and all process parameters are exactly the same as in Example 1.

[0064] Performance test results: breakage rate 1.2%, boiling time 12 min, turbidity absorbance 0.048, hardness 4500g, elasticity 0.93, chewiness 3400g・s, in vitro GI value 58, fat content 0.7%, sensory score 90 points.

[0065] This embodiment reduces the proportion of low-GI cereal flour and increases the content of high-gluten wheat flour, making the gluten network of the noodles more complete and the texture characteristics closer to traditional Hong Kong-style cart noodles. The noodles have a chewy and smooth texture, proving that the process of this invention can achieve a good balance between texture and GI value under different raw material ratios.

[0066] Example 3

[0067] This embodiment is used to verify the strengthening effect of the double crosslinking technology of the present invention on the texture of Chezai noodles and the performance of the GI value when the amount of low-GI cereal flour added is 80 parts and the amount of high-gluten wheat flour is 20 parts.

[0068] Preparation steps

[0069] The only difference from Example 1 is the raw material compounding step: 40 parts buckwheat flour, 40 parts mung bean flour, and 20 parts high-gluten wheat flour are weighed out. The other types of raw materials, the amount added, and all process parameters are exactly the same as in Example 1.

[0070] Performance test results: breakage rate 1.8%, boiling time 11 min, turbidity absorbance 0.058, hardness 3900g, elasticity 0.90, chewiness 2900g・s, in vitro GI value 49, fat content 0.6%, sensory score 88 points.

[0071] This embodiment significantly increases the proportion of low-GI grain flour added, and the product's GI value is significantly reduced to 49. Although the gluten network of high-proportion low-GI grains is weak, a stable protein-starch interpenetrating network is still successfully constructed through the ultrasound-assisted enzyme crosslinking and double crosslinking technology of this invention, so that the breakage rate of noodles is controlled within 2%. This effectively solves the industry problem of traditional high-proportion low-GI grain noodles being easy to break and having poor taste, and is suitable for long-term consumption by diabetic patients and people who strictly control their blood sugar.

[0072] Comparative Example 1

[0073] This comparative example is used to verify the basic performance defects of cart noodles prepared with low-GI grain flour as the main raw material without any cross-linking technology.

[0074] Preparation steps

[0075] The only difference from Example 1 is that the ultrasound-assisted enzymatic protein crosslinking step (S200) and the ultrasound-assisted pH cycle dual crosslinking step (S300) are omitted. After the raw materials are compounded, they are directly calendered and cut into strips. All other process parameters are exactly the same as those in Example 1.

[0076] Performance test results: breakage rate 12.4%, boiling time 4 min, turbidity absorbance 0.215, hardness 1800g, elasticity 0.65, chewiness 850g・s, in vitro GI value 72, fat content 0.7%, sensory score 52 points.

[0077] This comparative example did not employ any cross-linking technology. The low-GI cereal protein failed to form an effective three-dimensional network structure, resulting in starch granules lacking encapsulation and binding. This led to extremely poor noodle resistance during cooking, with numerous noodles breaking apart and the broth becoming severely cloudy, resulting in a soft, mushy texture lacking any chewiness. Simultaneously, the starch rapidly gelatinized and was broken down by amylase, causing the GI value to rise sharply to 72, classifying it as a high-GI food. This completely fails to meet the dietary needs of people controlling their blood sugar levels, demonstrating that cross-linking technology is the core key to preparing low-GI, high-quality cart noodles.

[0078] Comparative Example 2

[0079] This comparative example is used to verify the effect of a single transglutaminase crosslinking process on the performance of Chezai noodles without low-frequency ultrasound assistance.

[0080] Preparation steps

[0081] The only difference from Example 1 is that the ultrasound equipment is not turned on in the ultrasound-assisted enzymatic protein crosslinking step (S200) and the ultrasound-assisted pH cycle dual crosslinking step (S300). The reaction is carried out only under the corresponding temperature and pH conditions. All other process parameters are exactly the same as in Example 1.

[0082] Performance test results: breakage rate 5.6%, boiling time 7 min, turbidity absorbance 0.123, hardness 2700g, elasticity 0.78, chewiness 1600g・s, in vitro GI value 66, fat content 0.7%, sensory score 68 points.

[0083] This comparative example only used transglutaminase for cross-linking. Without ultrasound assistance, the contact area between the enzyme and the protein substrate was limited, resulting in low reaction efficiency, insufficient protein cross-linking degree, and an inability to form a dense three-dimensional network structure. The noodles' resistance to overcooking and textural properties were improved compared to the first comparative example, but significant problems with noodle breakage and broth clouding still existed. Furthermore, the starch digestion rate was not effectively slowed down, and the GI value was high, demonstrating that low-frequency ultrasound has a significant synergistic effect on the transglutaminase-catalyzed cross-linking reaction.

[0084] Comparative Example 3

[0085] This comparative example is used to verify the performance of Chezai noodles when only ultrasound-assisted transglutaminase cross-linking is used, without ultrasound-assisted pH cycling dual cross-linking.

[0086] Preparation steps

[0087] The only difference from Example 1 is that the ultrasonic-assisted pH cycle dual crosslinking step (S300) is omitted, and the ultrasonic-assisted enzymatic protein crosslinking step is completed before calendering and cutting into strips. All other process parameters are exactly the same as in Example 1.

[0088] Performance test results: breakage rate 2.5%, boiling time 9 min, turbidity absorbance 0.087, hardness 3500g, elasticity 0.85, chewiness 2300g・s, in vitro GI value 62, fat content 0.7%, sensory score 78 points.

[0089] This comparative example only constructed a single protein cross-linking network. Although it can improve the texture properties of noodles and reduce the breakage rate to some extent, it cannot effectively modify starch molecules. Starch granules are only physically wrapped by the protein network, and they are still prone to swelling and gelatinization during cooking and rapid decomposition by amylases. This results in the GI value not being able to be reduced to the low GI range, proving that single protein cross-linking technology cannot simultaneously achieve texture improvement and significant GI value reduction, highlighting the importance of dual cross-linking technology.

[0090] Comparative Example 4

[0091] This comparative example is used to verify the performance of cart noodles when only ultrasonic-assisted pH cycling starch esterification is performed, without transglutaminase protein cross-linking.

[0092] Preparation steps

[0093] The only difference from Example 1 is that transglutaminase is not added in the ultrasound-assisted enzymatic protein crosslinking step (S200), and only ultrasound treatment with the same parameters is performed. All other process parameters are exactly the same as in Example 1.

[0094] Performance test results: breakage rate 8.7%, boiling time 5 min, turbidity absorbance 0.168, hardness 2200g, elasticity 0.72, chewiness 1100g・s, in vitro GI value 69, fat content 0.6%, sensory score 61 points.

[0095] This comparative example only involved starch esterification modification, lacking the basic network structure formed by protein cross-linking. The dough texture was loose, the degree of starch esterification reaction was low, and the modified starch molecules could not form a stable network. The noodles had poor cooking resistance, broke easily, clouded the broth, and had a sticky texture. At the same time, the GI value was still at a high level, proving that protein cross-linking is the basis for building a stable protein-starch interpenetrating network. Single starch modification technology cannot simultaneously meet the dual requirements of texture and low GI.

[0096] Comparative Example 5

[0097] This comparative example is used to verify the performance of Chezi noodles without ultrasonic synergy, driven solely by pH cycling for double crosslinking.

[0098] Preparation steps

[0099] The only difference from Example 1 is that the ultrasound equipment is not turned on in the ultrasound-assisted enzymatic protein crosslinking step (S200) and the ultrasound-assisted pH cycle dual crosslinking step (S300). The protein crosslinking and starch esterification reaction are driven only by pH changes. All other process parameters are exactly the same as in Example 1.

[0100] Performance test results: breakage rate 6.3%, boiling time 6 min, turbidity absorbance 0.135, hardness 2900g, elasticity 0.80, chewiness 1800g・s, in vitro GI value 64, fat content 0.7%, sensory score 65 points.

[0101] This comparative example only used pH cycling to drive the dual crosslinking reaction, without the assistance of ultrasonic cavitation. The reaction rate and extent of protein crosslinking and starch esterification were significantly reduced, failing to form a complete protein-starch covalently interpenetrating network. The texture properties and GI value of the noodles were inferior to those of Example 1, demonstrating that ultrasound not only improves the efficiency of enzymatic crosslinking but also promotes the esterification reaction between citric acid and starch hydroxyl groups, making it an indispensable synergistic means in dual crosslinking technology.

[0102] Comparative Example 6

[0103] This comparative example is used to verify the performance difference between cart noodles prepared by traditional frying process and the non-frying process product of the present invention.

[0104] Preparation steps

[0105] The only difference from Example 1 is that the non-fried shaping and drying step (S500) is replaced by a frying shaping process. The steamed noodles are fried at 160°C for 1.5 minutes, deoiled, and cooled to room temperature, with the moisture content controlled at 10%. All other process parameters are exactly the same as in Example 1.

[0106] Performance test results: breakage rate 0.7%, boiling time 12 min, turbidity absorbance 0.045, hardness 4300g, elasticity 0.92, chewiness 3300g・s, in vitro GI value 54, fat content 22.3%, sensory score 91 points.

[0107] This comparative example uses a traditional frying process. The texture, GI value, and flavor of the product are similar to those of Example 1, but the fat content is as high as 22.3%. Long-term consumption of fried cart noodles can easily lead to excessive fat intake and increase health risks. This proves that the non-fried segmented drying process of the present invention significantly improves health while maintaining the excellent quality of the product.

[0108] Comparative Example 7

[0109] This comparative example is used to verify the GI value performance of cart noodles obtained using 100 parts of high-gluten wheat flour as raw material and the preparation process of this invention.

[0110] Preparation steps

[0111] The only difference from Example 1 is that: no low-GI grain flour is added in the raw material compounding step, and 100 parts of high-gluten wheat flour are used. The other raw material types, addition amounts and all process parameters are exactly the same as in Example 1.

[0112] Performance test results: breakage rate 0.5%, boiling time 14 min, turbidity absorbance 0.042, hardness 4600g, elasticity 0.94, chewiness 3500g・s, in vitro GI value 83, fat content 0.7%, sensory score 93 points.

[0113] This comparative example uses high-gluten wheat flour as raw material. The noodles prepared by the cross-linking process of this invention have excellent texture and flavor, but the GI value is as high as 83, which is a typical high-GI food. After consumption, blood sugar rises rapidly and it is not suitable for people with diabetes or those who need to control their blood sugar. This proves that low-GI grain compounding is the basis for reducing the GI value of the product.

[0114] To visually present the performance differences of various technical solutions and comprehensively compare the advantages and disadvantages of the product of this invention with existing technology products, the performance test results of all the above embodiments and comparative examples are summarized in the following table:

[0115] Sample number Broken strip rate (%) Cooking time (min) Clarity of the liquid (absorbance) Hardness (g) elasticity In vitro GI value Fat content (%) Example 1 0.8 13 0.052 4200 0.92 53 0.7 Example 2 1.2 12 0.048 4500 0.93 58 0.7 Example 3 1.8 11 0.058 3900 0.90 49 0.6 Comparative Example 1 12.4 4 0.215 1800 0.65 72 0.7 Comparative Example 2 5.6 7 0.123 2700 0.78 66 0.7 Comparative Example 3 2.5 9 0.087 3500 0.85 62 0.7 Comparative Example 4 8.7 5 0.168 2200 0.72 69 0.6 Comparative Example 5 6.3 6 0.135 2900 0.80 64 0.7 Comparative Example 6 0.7 12 0.045 4300 0.92 54 22.3 Comparative Example 7 0.5 14 0.042 4600 0.94 83 0.7

[0116] Based on the data in the table above and the technical differences between the various embodiments and comparative examples, it can be seen that:

[0117] This invention achieves a synergistic breakthrough in low GI and high quality, with broad raw material adaptability. Examples 1 to 3 cover the entire ratio range of 60-80 parts low GI grain powder. Example 1 achieves the optimal balance in overall performance, with a breakage rate as low as 0.8%, a cooking time of up to 13 minutes, and extremely low turbidity in the broth. Simultaneously, it has an in vitro GI value of 53 and a fat content of only 0.7%, perfectly balancing health and eating experience. Example 2 is closer to the texture of traditional noodles, suitable for the mass consumer market. Example 3 has a GI value as low as 49, meeting the special needs of people with diabetes, gestational diabetes, and other groups requiring strict blood sugar control. This demonstrates that the process of this invention can flexibly adjust the raw material ratio according to different consumption scenarios.

[0118] Comparative Example 1, which did not employ any cross-linking technology, had a breakage rate 15.5 times that of Example 1, with a GI value increasing by 35.8%, completely losing its commercial value. Comparative Examples 2 and 5, lacking ultrasound assistance, saw a decrease in protein cross-linking degree and starch esterification rate of approximately 40% and 35%, respectively, leading to a breakage rate exceeding 5% and a GI value exceeding 65. Comparative Example 3, using only single-protein cross-linking, failed to covalently modify the starch, and the starch digestion rate was not effectively inhibited, resulting in a GI value as high as 62. Comparative Example 4, using only single-starch esterification, lacked protein network support, resulting in a loose dough structure and a breakage rate of 8.7%. The data fully demonstrate that the ultrasonic cavitation effect is key to improving reaction efficiency, while the protein-starch covalently interpenetrating network is the core structural basis for simultaneously achieving textural enhancement and GI value reduction; both are indispensable.

[0119] The non-fried, segmented drying process achieves a fundamental improvement in health without sacrificing quality. A comparison of Example 1 and Comparative Example 6 shows no statistically significant differences in texture, cookability, GI value, and sensory evaluation. However, the non-fried product of this invention has a fat content of only 0.7%, far lower than the 22.3% of the fried product, thus solving the drawbacks of traditional fried cart noodles being excessively high in fat and prone to health problems with long-term consumption.

[0120] The combination of low-GI raw materials and the double cross-linking technology exhibits a significant synergistic effect. Comparing Example 1 and Comparative Example 7, it is evident that even using the double cross-linking process of this invention, the product prepared from high-gluten wheat flour still has a GI value as high as 83, classifying it as a high-GI food. In contrast, Comparative Example 1, which only used a low-GI raw material combination without cross-linking technology, not only had extremely poor texture but also a GI value as high as 72. Only by organically combining low-GI grains with the double cross-linking technology can we both reduce the basal digestibility of starch through low-GI grains and further restrict starch gelatinization and enzymatic hydrolysis through the protein-starch interpenetrating network, ultimately achieving a significant reduction in the product's GI value and a simultaneous improvement in texture.

[0121] In summary, the raw materials used in this invention are all commonly used in the food industry, and are inexpensive and readily available; the core process equipment are all general-purpose equipment in the flour product industry, requiring no large-scale production line modifications and meeting the requirements of continuous industrial production.

[0122] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing low-GI non-fried Hong Kong-style cart noodles, characterized in that, The specific steps of this method are as follows: S100, Raw material compounding: Take low-GI grain flour, high-gluten wheat flour, soy protein isolate, edible salt, compound phosphate, and Hong Kong-style flavor improver. Mix the raw materials evenly and add drinking water at 35-40% of the total flour weight. Stir to obtain dough. S200, Ultrasonic-assisted Enzymatic Protein Crosslinking: Transglutaminase was added to the dough obtained by S100, and the enzymatic crosslinking reaction was carried out under low-frequency ultrasound conditions; S300, Ultrasonic Synergistic pH Cycling Dual Crosslinking: Citric acid is added to the dough treated with S200, and a pH cycling process is used to simultaneously drive the protein crosslinking reaction catalyzed by transglutaminase and the esterification reaction of citric acid and starch hydroxyl groups to form a protein-starch covalent interpenetrating network. S400, rolling and cutting: The dough treated by S300 is rolled multiple times until it reaches the preset thickness and then cut into strips to obtain the cart noodle raw dough; S500, Non-fried Shaping and Drying: The cart noodle raw material obtained by S400 is steamed and shaped, and then dried with segmented hot air to the preset moisture content to obtain a low-GI non-fried Hong Kong-style cart noodle finished product.

2. The method for preparing low-GI non-fried Hong Kong-style cart noodles according to claim 1, characterized in that, In S100, the low-GI cereal powder is a mixture of buckwheat flour and mung bean flour in a mass ratio of 1:

1. By weight, the amount of each ingredient added is as follows: 60-80 parts of low-GI cereal powder, 20-40 parts of high-gluten wheat flour, 8 parts of soy protein isolate, 1-2 parts of edible salt, 0.3-0.5 parts of compound phosphate, and 0.5-1 parts of Hong Kong-style flavor improver.

3. The method for preparing low-GI non-fried Hong Kong-style cart noodles according to claim 2, characterized in that, The composite phosphate is a mixture of sodium hexametaphosphate, sodium tripolyphosphate, and sodium pyrophosphate in a mass ratio of 45:27.5:27.

5.

4. The method for preparing low-GI non-fried Hong Kong-style cart noodles according to claim 2, characterized in that, The Hong Kong-style flavor improver is a mixture of maltodextrin, disodium inosinate, and spices in a mass ratio of 5:3:

2.

5. The method for preparing low-GI non-fried Hong Kong-style cart noodles according to claim 1, characterized in that, In the S200, the amount of transglutaminase added is 0.4 U / g protein; The process parameters for the low-frequency ultrasound are: frequency 40kHz, power 50W, processing time 15 minutes, and reaction temperature maintained at 40-45℃.

6. The method for preparing low-GI non-fried Hong Kong-style cart noodles according to claim 1, characterized in that, In the S300, the amount of citric acid added is 0.2%; The pH cycling process is as follows: the pH value of the dough system is adjusted to 7.5, and then treated for 10 minutes under the same low-frequency ultrasonic conditions; The pH of the system was lowered to 5.5 by introducing CO2 gas, and the reaction was continued for 5 minutes while maintaining the pH at 5.

5. Spray sodium carbonate solution to restore pH to 7.0 and continue sonication for 3 minutes.

7. The method for preparing low-GI non-fried Hong Kong-style cart noodles according to claim 1, characterized in that, In S400, during the rolling process, the dough is left to rest and rise for 15-20 minutes, then rolled into a sheet with a thickness of 1-1.5mm using a rolling mill, and then cut into noodles with a width of 2-3mm using a strip cutter to obtain the raw dough for cart noodles.

8. The method for preparing low-GI non-fried Hong Kong-style cart noodles according to claim 1, characterized in that, In the S500, the steaming and shaping process is as follows: the raw dough for cart noodles is placed in a steamer and steamed at 95-100℃ for 8-10 minutes until the noodles are fully cooked. The temperature of the hot air drying is 65℃ and the preset moisture content is 10%-12%.

9. The method for preparing low-GI non-fried Hong Kong-style cart noodles according to claim 1, characterized in that, In the S500, the segmented hot air drying process is as follows: the cooked noodles are sent into the hot air drying equipment, the first segment is dried at 60-70℃ for 30-40 minutes, the second segment is dried at 45-55℃ for 20-30 minutes, and the noodles are dried until the moisture content is 8-12%, thus obtaining the low-GI non-fried Hong Kong-style cart noodles.

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