Low gi extruded ice-macaroni flour without exogenous addition and its preparation method

Abstract

The application provides a low-GI ice wheat flour without external addition and a preparation method thereof, and belongs to the technical field of food. The method comprises the following steps: S1. selecting harvested mature ice wheat, removing impurities, shriveled grains and damaged particles, washing and draining to obtain pretreated ice wheat; S2. adopting a multi-stage light milling fine grinding process on the pretreated ice wheat to obtain ice wheat coarse powder; S3. screening the ice wheat coarse powder to remove particles that are not sufficiently ground, so as to obtain ice wheat fine powder with uniform particle size; and S4. detecting and packaging to obtain the low-GI ice wheat flour without external addition. The application realizes the technical effects of low-GI characteristics, high protein, high dietary fiber, full traceability and non-detection of pesticide residues, and meets the demand of consumers for natural, nutritious and safe low-GI flour.

Description

Technical Field

[0001] This invention relates to the field of food technology, specifically to a low-GI ice wheat flour without exogenous additives and its preparation method. Background Technology

[0002] With increasing health awareness among residents, low-GI (glycemic index) foods are gradually becoming the mainstream in the market, with low-GI flour experiencing continuous demand growth due to its suitability for daily staple foods. However, the current low-GI food market still faces four major pain points, severely hindering the industry's high-quality development: First, some low-GI flour products rely on the artificial addition of exogenous substances such as resistant starch and inulin to control the GI value, weakening the product's natural attributes and failing to meet consumers' demand for natural and healthy foods; second, the protein content of ordinary low-GI flour is mostly concentrated between 10% and 12%, with only slightly higher dietary fiber content than ordinary flour, resulting in a lack of nutritional diversity and failing to meet consumers' pursuit of diverse nutrition; third, the safety traceability system for some products in the industry is weak, with opaque information throughout the entire process from raw material planting to finished product sales, leading to insufficient consumer trust in product quality; fourth, product quality control levels vary widely. According to industry statistics, 35% of low-GI flour products have excessive pesticide residues, 11.2% of products fail pesticide residue testing, and some products lack complete traceability information, posing serious food safety risks.

[0003] Existing technologies for preparing low-GI flour present the following technical problems: 1. Reliance on exogenous GI-controlling ingredients weakens the product's natural properties, and some added ingredients affect the flour's original taste; 2. Limited nutritional content, with a protein content of only 10%-12%, failing to meet consumers' diverse needs for low-GI, high-protein, and high-dietary-fiber products; 3. Weak traceability system, lack of transparency throughout the process, leading to low consumer trust in product quality; 4. Inconsistent quality control, with 35% of products exceeding pesticide residue limits and 11.2% failing testing, posing food safety risks; 5. Crude milling process, with room-temperature grinding leading to nutrient loss, and starch gelatinization indirectly increasing the GI value. Therefore, developing a low-GI general-purpose wheat flour that requires no exogenous additives, offers significant nutritional advantages, is fully traceable, and has undetectable pesticide residues, along with its preparation method, has become an urgent technical challenge. Summary of the Invention

[0004] The purpose of this invention is to propose a low-GI ice wheat flour without external additives and its preparation method. In response to the deficiencies of existing technologies, this invention provides a general-purpose low-GI ice wheat flour and its preparation method, which precisely addresses the four major pain points of the current low-GI flour market. It achieves the technical effects of low-GI characteristics, high protein, high dietary fiber, full traceability, and undetectable pesticide residues, thus meeting consumers' demand for natural, nutritious, and safe low-GI flour.

[0005] The technical solution of this invention is implemented as follows: This invention provides a method for preparing low-GI ice wheat flour without exogenous additives, comprising the following steps: S1. Select harvested mature ice wheat, remove impurities, shriveled grains and broken grains, wash and drain to obtain pre-treated ice wheat; S2. The pretreated ice wheat is subjected to a multi-stage light and fine grinding process to obtain ice wheat coarse powder; S3. Screen the coarse wheat flour to remove insufficiently ground particles and obtain fine wheat flour with uniform particle size; S4. Testing and packaging to produce low-GI ice wheat flour without any exogenous additives.

[0006] The product of this invention uses high-quality wheat with high protein and high dietary fiber as the core raw material. Its protein content is ≥14%, and its endogenous dietary fiber content is higher than that of ordinary wheat. Based on this nutritional composition, the raw material exhibits slow digestion characteristics in human in vitro simulated digestion experiments. On this basis, a room temperature multi-stage gradient grinding process is adopted to achieve synergistic effect between the natural advantages of the raw material and the precise control of the process. Stable low-GI products can be prepared without adding any exogenous substances.

[0007] Existing traditional wheat milling processes, particularly conventional roller milling, easily cause wheat starch granules to break down and decompose, damaging the microstructure of the grain itself. This invention utilizes a multi-pass, room-temperature, graded, and finely milling process system to fully leverage the inherent advantages of wheat's natural high protein (≥14%) and high dietary fiber content. The entire process employs low-pressure, low-shear, and low-speed gentle milling, resulting in minimal frictional temperature rise and low mechanical damage during the milling process. On the one hand, it avoids the breakage of starch granules and tearing of crystal structure caused by strong crushing and high shearing, and retains the original complete starch granules and dense arrangement of amylose in Xiaobingmai to the greatest extent. It effectively inhibits the thermal gelatinization of starch caused by high grinding temperature, greatly reduces the proportion of gelatinized starch that is easily digested by human enzymes, and increases the retention of slow-digestible starch and resistant starch. On the other hand, the three-stage light milling process gently separates the bran from the endosperm, without disrupting the natural gluten protein network structure or excessively pulverizing dietary fiber. This maintains the natural physical encapsulation and digestive barrier system of protein and fiber around starch granules, slowing down the contact and decomposition rate of starch with digestive amylase, and thus delaying the release and absorption of glucose in the body. No exogenous glycemic index (GI) lowering agents are added throughout the entire process; the process only controls the integrity of the starch, its crystal structure, and the coating state of the protein fiber to achieve stable production of low-GI wheat flour.

[0008] This special grinding process preserves the structural integrity of wheat starch granules to the greatest extent possible, effectively controlling the proportion of starch components: significantly increasing the relative content of resistant starch and amylose, and reducing the proportion of amylopectin. Since amylopectin is easily digested and absorbed by the human body and has a high glycemic index, while resistant starch and amylose are digested and decomposed at a slower rate, this optimized reconstruction of starch components significantly reduces the glycemic index (GI) of wheat flour from a material perspective, achieving low GI characteristics.

[0009] Therefore, this process requires no additional exogenous dietary fiber, low-glycemic substances, or food additives. It relies entirely on the natural advantages of the high-protein, high-fiber germplasm of wheat itself. Through precise and exclusive control of the multi-stage grinding process gradient, shear strength, and particle breakage, it achieves the directional reshaping and optimized arrangement of the starch, protein, and dietary fiber three-phase structure at the microscopic physical level. Relying on the synergistic barrier effect of the raw materials' own endogenous components, it stably achieves the low-GI characteristics of the finished flour. At the same time, the entire process parameters are standardized and extremely stable, the production process is clean and green with no waste emissions, and can be directly implemented for large-scale industrial production.

[0010] As a further improvement of the present invention, in step S2, the temperature condition of the multi-stage light grinding process is room temperature.

[0011] As a further improvement of the present invention, in step S2, the multi-stage light grinding process includes: a leather mill, a slag mill, and a core mill. The leather mill process involves three grinding cycles, with each grinding cycle having a rotation speed of 200-250 rpm. The slag mill process involves one grinding cycle, with a rotation speed of 300-350 rpm. The core mill process involves three grinding cycles, with each grinding cycle having a rotation speed of 400-450 rpm.

[0012] As a further improvement of the present invention, in step S2, the particle size of the ice wheat coarse powder is 80-100 mesh.

[0013] As a further improvement of the present invention, in step S4, the detection includes pesticide residue detection, protein content detection, dietary fiber detection and GI value detection.

[0014] As a further improvement of the present invention, the pesticide residue detection adopts high performance liquid chromatography combined with gas chromatography, and the detection limit is ≤0.01mg / kg.

[0015] As a further improvement of the present invention, the GI value is detected by in vitro digestion method; the protein content is detected by Kjeldahl method, specifically according to GB 5009.5-2025 National Food Safety Standard for Determination of Protein in Food; and the dietary fiber content is detected by enzyme gravimetric method, specifically according to GB 5009.88-2023 National Food Safety Standard for Determination of Dietary Fiber in Food.

[0016] The present invention further protects a low-GI ice wheat flour without exogenous additives prepared by the above-mentioned preparation method, wherein the low-GI ice wheat flour has a GI value ≤55, a protein content ≥14%, and a dietary fiber content ≥10%.

[0017] This invention achieves precise and controllable regulation of grinding shear intensity by constructing a gradient matching system for process parameters, and uses a proprietary processing logic to directionally reshape the microstructure of small-grain wheat powder. It fully leverages the unique raw material properties of small-grain wheat, using its natural characteristics as a foundation, combined with a self-constructed parameter combination and process path, forming a dual, unreplicable technological barrier of raw material characteristics and proprietary processing methods. Even when conventional wheat is ground at the same room temperature, the lack of inherent structural properties and the absence of a matching gradient process and shear intensity control logic prevent precise modification of the starch microstructure, making it difficult to achieve low-GI quality without external additives. This highlights the specific adaptability and technological exclusivity of this process for Ji-brand small-grain wheat.

[0018] The present invention has the following beneficial effects: 1. Overcoming the pain point of "lack of outstanding nutritional advantages": The low-GI all-purpose flour prepared by this invention, which is free of exogenous added ice wheat, has a GI value of ≤55, a protein content of ≥14%, and a dietary fiber content of ≥10%. Compared with ordinary low-GI flour (protein content of 10%-12%), it has significant nutritional advantages, achieving the triple value of "low GI + high protein + high dietary fiber", meeting consumers' dual needs for diverse nutrition and health, and solving the defect of the single nutrition of existing low-GI flour.

[0019] 2. Addressing the pain points of "excessive pesticide residues and poor quality control": This invention establishes a full-chain pesticide residue control system, from input control and growth process monitoring in the planting stage to raw material testing and finished product testing in the processing stage. It implements strict controls at every level and uses high-precision testing methods to ensure a 100% non-detection rate of pesticide residues, thus completely solving the problems of excessive pesticide residues and inconsistent quality control in existing products and ensuring food safety.

[0020] 3. Scientific and reasonable preparation process: The process adopts a room temperature multi-stage light grinding process to effectively retain the protein, dietary fiber and other nutrients in the iced wheat, and avoids nutrient loss and GI value increase caused by high temperature; the entire preparation process is standardized and the parameters are controllable, which is suitable for large-scale industrial production, and the production process has no pollutant emissions, which meets the requirements of green production.

[0021] 4. High versatility: The ice wheat low-GI all-purpose flour prepared by this invention can be widely used in the production of various staple foods such as steamed buns, noodles, dumplings, and bread without the need for additional ingredients. It is suitable for daily cooking scenarios, has high practicality, and has broad market application prospects. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example 1

[0023] This embodiment provides a low-GI ice wheat flour, the preparation method of which includes the following steps: S1. Raw material selection and pretreatment: Select harvested mature ice wheat, remove impurities, shriveled grains and broken grains, wash and drain to obtain pretreated ice wheat; S2. Low-Temperature Grinding: The pretreated frozen wheat is fed into a low-temperature grinding device. The grinding temperature is controlled at room temperature, and a multi-stage light grinding process is adopted, including: bran grinding, residue grinding, and core grinding. The bran grinding process involves three grindings, each at a speed of 200 rpm. The residue grinding process involves one grinding at a speed of 300 rpm. The core grinding process involves three grindings, each at a speed of 400 rpm, to obtain coarse frozen wheat powder with a particle size of 80 mesh. Low-temperature grinding can effectively retain the protein, dietary fiber, and other nutrients in frozen wheat, while avoiding starch gelatinization that leads to an increase in the GI value. S3. Screening and impurity removal: The coarse wheat flour is fed into a precision screening device to remove insufficiently ground particles, resulting in fine wheat flour with uniform particle size. A negative pressure dust removal process is used during the screening process to avoid dust pollution and ensure product hygiene. S4. Pesticide Residue and Quality Testing: A comprehensive pesticide residue test will be conducted on the ice wheat flour, including common pesticide residues such as organophosphates and pyrethroids. The GI value, protein content, dietary fiber content, and moisture content will also be tested to ensure the results meet the standards (the ice wheat low-GI flour should have a GI value ≤ 55, protein content ≥ 14%, dietary fiber content ≥ 10%, pesticide residue test result of undetectable, and moisture content of 12-14%). Any products that fail the test will be rejected and will not proceed to the next stage. Pesticide residue detection employs a combination of high-performance liquid chromatography and gas chromatography to ensure detection accuracy, with a detection limit ≤0.01 mg / kg; GI value detection uses an in vitro digestion method; protein content detection uses the Kjeldahl method; and dietary fiber content detection uses an enzyme gravimetric method.

[0024] S5. Mixing and homogenization: The qualified ice wheat fine flour is fed into the mixing equipment and mixed at 150 rpm for 10 minutes to ensure that the flour particle size and nutrients are evenly distributed, so as to obtain the finished ice wheat low-GI general flour. S6. Packaging and Traceability Coding: Finished flour is sealed in food-grade packaging materials, and aseptic operations are carried out during the packaging process to avoid secondary contamination; each packaging unit is assigned a unique traceability code, which is linked to information on the entire process of wheat planting, harvesting, processing, and testing. Consumers can scan the code to query detailed traceability information. Example 2

[0025] This embodiment provides a low-GI ice wheat flour, the preparation method of which includes the following steps: S1. Raw material selection and pretreatment: Select harvested mature ice wheat, remove impurities, shriveled grains and broken grains, wash and drain to obtain pretreated ice wheat; S2. Low-Temperature Grinding: The pretreated frozen wheat is fed into a low-temperature grinding device. The grinding temperature is controlled at room temperature, and a multi-stage light grinding process is adopted, including: bran grinding, residue grinding, and core grinding. The bran grinding process involves three grindings, each at a speed of 250 rpm. The residue grinding process involves one grinding at a speed of 350 rpm. The core grinding process involves three grindings, each at a speed of 450 rpm, to obtain coarse frozen wheat powder with a particle size of 100 mesh. Low-temperature grinding can effectively retain the protein, dietary fiber, and other nutrients in frozen wheat, while avoiding starch gelatinization that leads to an increase in the GI value. S3. Screening and impurity removal: The coarse wheat flour is fed into a precision screening device to remove insufficiently ground particles, resulting in fine wheat flour with uniform particle size. A negative pressure dust removal process is used during the screening process to avoid dust pollution and ensure product hygiene. S4. Pesticide Residue and Quality Testing: A comprehensive pesticide residue test will be conducted on the ice wheat flour, including common pesticide residues such as organophosphates and pyrethroids. The GI value, protein content, dietary fiber content, and moisture content will also be tested to ensure the results meet the standards (the ice wheat low-GI flour should have a GI value ≤ 55, protein content ≥ 14%, dietary fiber content ≥ 10%, pesticide residue test result of undetectable, and moisture content of 12-14%). Any products that fail the test will be rejected and will not proceed to the next stage. Pesticide residue detection employs a combination of high-performance liquid chromatography and gas chromatography to ensure detection accuracy, with a detection limit ≤0.01 mg / kg; GI value detection uses an in vitro digestion method; protein content detection uses the Kjeldahl method; and dietary fiber content detection uses an enzyme gravimetric method.

[0026] S5. Mixing and homogenization: The qualified ice wheat fine flour is fed into the mixing equipment and mixed at 200 rpm for 15 minutes to ensure that the flour particle size and nutrients are evenly distributed, so as to obtain the finished ice wheat low-GI general flour. S6. Packaging and Traceability Coding: Finished flour is sealed in food-grade packaging materials, and aseptic operations are carried out during the packaging process to avoid secondary contamination; each packaging unit is assigned a unique traceability code, which is linked to information on the entire process of wheat planting, harvesting, processing, and testing. Consumers can scan the code to query detailed traceability information. Example 3

[0027] This embodiment provides a low-GI ice wheat flour, the preparation method of which includes the following steps: S1. Raw material selection and pretreatment: Select harvested mature ice wheat, remove impurities, shriveled grains and broken grains, wash and drain to obtain pretreated ice wheat; S2. Low-Temperature Grinding: The pretreated frozen wheat is fed into a low-temperature grinding device. The grinding temperature is controlled at room temperature, and a multi-stage light grinding process is adopted, including: bran grinding, residue grinding, and core grinding. The bran grinding process involves three grindings, each at a speed of 220 rpm. The residue grinding process involves one grinding at a speed of 320 rpm. The core grinding process involves three grindings, each at a speed of 420 rpm, to obtain coarse frozen wheat powder with a particle size of 90 mesh. Low-temperature grinding can effectively retain the protein, dietary fiber, and other nutrients in frozen wheat, while avoiding starch gelatinization that leads to an increase in the GI value. S3. Screening and impurity removal: The coarse wheat flour is fed into a precision screening device to remove insufficiently ground particles, resulting in fine wheat flour with uniform particle size. A negative pressure dust removal process is used during the screening process to avoid dust pollution and ensure product hygiene. S4. Pesticide Residue and Quality Testing: A comprehensive pesticide residue test will be conducted on the ice wheat flour, including common pesticide residues such as organophosphates and pyrethroids. The GI value, protein content, dietary fiber content, and moisture content will also be tested to ensure the results meet the standards (the ice wheat low-GI flour should have a GI value ≤ 55, protein content ≥ 14%, dietary fiber content ≥ 10%, pesticide residue test result of undetectable, and moisture content of 12-14%). Any products that fail the test will be rejected and will not proceed to the next stage. S5. Mixing and homogenization: The qualified ice wheat fine flour is fed into the mixing equipment and mixed at 170 rpm for 12 minutes to ensure that the flour particle size and nutrients are evenly distributed, so as to obtain the finished ice wheat low-GI general flour. S6. Packaging and Traceability Coding: Finished flour is sealed in food-grade packaging materials, and aseptic operations are carried out during the packaging process to avoid secondary contamination; each packaging unit is assigned a unique traceability code, which is linked to information on the entire process of wheat planting, harvesting, processing, and testing. Consumers can scan the code to query detailed traceability information.

[0028] Comparative Example 1 The difference from Example 3 is that the grinding temperature in step S2 is 60°C.

[0029] Test Example 1 The ice wheat low-GI flours prepared in Examples 1-3 and Comparative Example 1 were tested, and the results are shown in Table 1.

[0030] Pesticide residue detection employs a combination of high-performance liquid chromatography and gas chromatography to ensure detection accuracy, with a detection limit ≤0.01 mg / kg; GI value detection uses an in vitro digestion method; protein content detection uses the Kjeldahl method; and dietary fiber content detection uses an enzyme gravimetric method.

[0031] Table 1

[0032] As shown in the table above, the pesticide residues of the ice wheat low-GI flour prepared in Examples 1-3 of the present invention were not detected, and the GI value was ≤55, the protein content was ≥14%, the dietary fiber content was ≥10%, and the moisture content was 12-14%.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing low-GI ice wheat flour without exogenous additives, characterized in that, Includes the following steps: S1. Select harvested mature ice wheat, remove impurities, shriveled grains and broken grains, wash and drain to obtain pre-treated ice wheat; S2. The pretreated ice wheat is subjected to a multi-stage light and fine grinding process to obtain ice wheat coarse powder; S3. Screen the coarse wheat flour to remove insufficiently ground particles and obtain fine wheat flour with uniform particle size; S4. Testing and packaging to produce low-GI ice wheat flour without any exogenous additives.

2. The preparation method according to claim 1, characterized in that, In step S2, the temperature condition for the multi-stage light grinding process is room temperature.

3. The preparation method according to claim 1, characterized in that, In step S2, the multi-stage light grinding process includes: leather grinding, slag grinding and core grinding. The leather grinding process involves three grindings, with a grinding speed of 200-250 rpm for each grinding. The slag grinding process involves one grinding, with a grinding speed of 300-350 rpm for each grinding. The core grinding process involves three grindings, with a grinding speed of 400-450 rpm for each grinding.

4. The preparation method according to claim 1, characterized in that, In step S2, the particle size of the coarse wheat flour is 80-100 mesh.

5. The preparation method according to claim 1, characterized in that, In step S4, the detection includes pesticide residue detection, protein content detection, dietary fiber detection, and GI value detection.

6. The preparation method according to claim 5, characterized in that, The pesticide residue detection method uses high performance liquid chromatography combined with gas chromatography, with a detection limit of ≤0.01mg / kg.

7. The preparation method according to claim 6, characterized in that, The GI value was detected using an in vitro human digestion simulation experiment and an in vivo food glycemic index assessment method; the protein content was detected using the Kjeldahl method, and the dietary fiber content was detected using an enzyme gravimetric method.

8. A low-GI ice wheat flour without exogenous additives prepared by the preparation method according to any one of claims 1-7, characterized in that, The ice wheat low-GI flour has a GI value ≤ 55, a protein content ≥ 14%, and a dietary fiber content ≥ 10%.

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