Time-sharing controlled-release sugar type composite cereal nutritional powder and preparation method and application thereof

Abstract

This invention discloses a time-release, slow-release, blood sugar-controlled compound cereal nutritional powder, its preparation method, and its applications, belonging to the field of functional cereal food technology. It comprises: 10-15 parts of fast-phase particles, 35-45 parts of slow-phase gradient-degrading gel microspheres, and 30-40 parts of complementary-phase particles; each is an independent particle form, and after oral administration, they act sequentially during gastrointestinal digestion: the fast-phase particles first contact the digestive juices, releasing a small amount of rapidly energy-providing dextrin within 5-10 minutes and stimulating the satiety center; the slow-phase gradient-degrading gel microspheres then gradually degrade, continuously releasing carbohydrates 1-3 hours after a meal; the complementary-phase particles begin to degrade 3 hours after a meal, supplementing energy supply in the late postprandial period; thus, they synergistically achieve stable blood sugar control throughout the postprandial period. This invention can match the insulin secretion window to control blood sugar, precisely delaying energy release to avoid late postprandial hypoglycemia, and achieving stable blood sugar control throughout the postprandial period.

Description

Technical Field

[0001] This invention relates to the field of functional cereal food technology, specifically to a time-release, slow-release, sugar-controlled compound cereal nutritional powder, its preparation method, and its application. Background Technology

[0002] Impaired glucose tolerance (IGT) is the core pathological feature of individuals with prediabetes and gestational hyperglycemia. Its glucose metabolism exhibits a typical "tri-phase imbalance" pattern: rapid rise in blood glucose within 0.5-1 hour after a meal (rapid phase abnormality); excessively high blood glucose peaks within 1-3 hours due to relative insulin insufficiency followed by a slow decline (slow phase abnormality); and reactive hypoglycemia 3-4 hours after a meal due to excessive insulin secretion in the preceding period or depletion of carbohydrate reserves (complementary phase deficiency). This pathological feature dictates that blood glucose-controlled foods cannot simply "slow down the overall carbohydrate intake" but must precisely match the glucose metabolism curve over time. However, current blood glucose-controlled food technologies generally employ a single slow-release strategy, i.e., reducing the overall glycemic index (GI) of food by adding resistant starch, dietary fiber, or performing physical / chemical modifications. While this "one-size-fits-all" slow-release approach can reduce postprandial blood glucose peaks to some extent, it cannot adapt to the unique tri-phase metabolic rhythm of IGT individuals, leading to the persistent clinical pain points of "not feeling full after blood glucose control and slow release that is not gradual."

[0003] Single-release slow-release staple foods for blood sugar control: Among existing technologies, low-GI multigrain compound powders are the most common form of staple foods for blood sugar control. For example, some technologies combine oats, barley, highland barley, buckwheat, and other whole grain raw materials after ultra-fine grinding, utilizing the dietary fiber content of the raw materials to achieve overall slow release of carbohydrates. Other technologies use high amylose corn starch combined with oat β-glucan, where β-glucan forms a physical barrier on the surface of starch granules, delaying the hydrolysis of starch by amylase. The above solutions only achieve an "overall downregulation" of the carbohydrate digestion rate, failing to design the phased release sequence of carbohydrates. For people with IGT, this overall slow release leads to two problems: first, insufficient energy supply in the early stages of eating (0.5-1 hour), triggering hunger and compensatory eating; second, depletion of carbohydrate reserves 3-4 hours after a meal, failing to prevent reactive hypoglycemia.

[0004] Resistant Starch Modification Technology: Resistant starch (RS) is widely used in sugar-controlled foods due to its resistance to enzymatic hydrolysis. Current technologies primarily improve the digestibility of starch through physical modification (such as high-temperature and high-pressure treatment, annealing and recrystallization) or chemical modification (such as cross-linking and esterification). Recent studies have used high-amylose corn starch to form V-shaped crystal inclusion complexes (RS5 type) with polyphenols (such as caffeic acid and chlorogenic acid), utilizing the competitive inhibition of α-amylase by polyphenols to achieve sustained release. Another technology involves the self-assembly of quinoa polyphenol extract and high-amylose corn starch to form an intestinal-targeted sustained-release complex. Although the above-mentioned resistant starch modification technology has improved the starch’s resistance to enzymatic hydrolysis, it has the following problems: (1) Polyphenol encapsulation usually uses a single starch matrix and lacks gradient degradation design, resulting in a “burst release” phenomenon in polyphenol release and an uneven sustained release curve; (2) The digestion delay of resistant starch is “passive” and cannot be actively regulated according to the blood glucose metabolism sequence of IGT populations; (3) Excessive resistance leads to a rough texture and poor reconstitution of food, and completely inhibits initial energy supply, aggravating hunger. Gel encapsulation controlled release technology: In the field of drug delivery, gel microsphere technology has been used to achieve gradient release of active ingredients, but its application in the field of controlled release of food carbohydrates is very rare. Existing gel applications in the food field are mainly focused on texture improvement (such as improving the water retention of meat products and improving the taste of noodle products) or sustained release of single components (such as β-glucan gel encapsulating theophylline), and there are no reports of applying gradient gel microsphere technology to the three-phase phase-separated controlled release of carbohydrates. Low-methoxylated pectin (LMP) and β-glucan are both food-grade gelling materials. LMP forms an irreversible gel through calcium ion crosslinking, while β-glucan forms a reversible gel through intermolecular hydrogen bonds. While existing technologies have studied the composite system of oat β-glucan and starch, finding that they can form a uniform and dense network structure through hydrogen bond crosslinking, reducing the digestibility and retrogradation of starch, they have not utilized the difference in degradation rates between the two gelling materials to construct a gradient controlled-release system. Prebiotic-assisted blood sugar control technology: Prebiotics (such as inulin, fructooligosaccharides, and galactooligosaccharides) assist in blood sugar control through mechanisms such as regulating gut microbiota and promoting the production of short-chain fatty acids, and have been used in various blood sugar control foods. Existing technologies typically use single prebiotics or simple mixtures, such as combining inulin and galactooligosaccharides in a fixed ratio for use in maternal milk powder, or using dietary fiber complex powder for blood sugar management during pregnancy. Technical shortcomings: Current prebiotic compounding schemes do not consider the differences in fermentation rates of prebiotics with different chain lengths and their synergistic relationship with the timing of carbohydrate release. Short-chain inulin ferments quickly (mainly acting on the proximal colon), long-chain inulin ferments slowly (mainly acting on the distal colon), and galactooligosaccharides ferment at a moderate rate. The fermentation kinetics curves of these three substances lack a time-matching design with the digestion and release curves of carbohydrates, resulting in the prebiotics' glycemic regulation effect failing to synergize with the metabolic rhythm of staple carbohydrates.The lack of dietary intervention for reactive hypoglycemia: Reactive hypoglycemia is a common complication in individuals with impaired glucose tolerance (IGT) 3-4 hours postprandial, characterized by a sharp drop in blood glucose to below 3.9 mmol / L, accompanied by symptoms such as hunger, tremors, dizziness, and difficulty concentrating. Current medical interventions mainly rely on dietary recommendations of "small, frequent meals" (eating every 3-4 hours) and the principle of "complex carbohydrates + protein + healthy fats," but lack technical solutions for proactively preventing reactive hypoglycemia through the timing of carbohydrate intake in food itself. Existing blood sugar-controlled foods generally focus on "reducing postprandial blood glucose peaks," leaving a complete lack of solutions for preventing delayed postprandial hypoglycemia. This is a core pain point that current technologies have neither discovered nor solved.

[0005] Based on the above analysis, the existing sugar control food technologies have the following common defects, which seriously restrict the blood glucose management effect of IGT people (including prediabetes, gestational hyperglycemia, etc.): (1) Lack of phase-sequential design: All existing technologies adopt the "overall sustained release" or "single controlled release" strategy, and do not design the phase-sequential release of carbohydrates according to the three-phase metabolic characteristics of "fast phase-slow phase-compensation phase" of IGT people, resulting in an imbalance between "sugar control" and "energy supply" in the time dimension. (2) Lack of gradient controlled release carriers: Although there are single controlled release methods such as resistant starch modification, polyphenol encapsulation, and gel encapsulation, a gradient controlled release system with "same components and different degradation rates" has not been constructed, and it is impossible to achieve smooth and continuous release of carbohydrates. (3) Lack of compensation phase prevention mechanism: Existing technologies do not pay attention to the reactive hypoglycemia problem 3-4 hours after meals, and lack technical means to actively fill the "carbohydrate window period" through food design.

[0006] Therefore, there is an urgent need to develop a new type of glucose-controlled food technology that can accurately match the three-phase glucose metabolism characteristics of IGT people, achieve phased targeted controlled release of carbohydrates, and prevent reactive hypoglycemia, so as to solve the systemic defects of existing technologies such as "glucose control without satiety, uneven slow release, and no guarantee of phase supplementation". Summary of the Invention

[0007] In order to overcome the shortcomings of the prior art, one of the objectives of this invention is to provide a time-release, slow-release, blood sugar-controlling compound grain nutritional powder. This time-release, slow-release, blood sugar-controlling compound grain nutritional powder can match the insulin secretion window to control blood sugar, accurately release energy to avoid late postprandial hypoglycemia, and achieve stable blood sugar control throughout the entire postprandial cycle.

[0008] The second objective of this invention is to provide a method for preparing a time-release, sugar-controlled compound grain nutritional powder. This method is simple and can be industrially produced as porous gel pet chewable snacks.

[0009] The third objective of this invention is to provide a time-release, slow-release, blood sugar-controlling compound cereal nutritional powder for the preparation of functional foods used to maintain stable postprandial blood glucose levels and avoid reactive postprandial hypoglycemia.

[0010] One of the objectives of this invention is achieved through the following technical solution: A time-release, sugar-controlled compound cereal nutritional powder, comprising the following components by weight: 10-15 parts of fast phase layer particles, 35-45 parts of slow phase layer gradient degradation gel microspheres, and 30-40 parts of supplementary phase layer particles; The fast-phase particles are prepared from low-glycemic whole grain raw materials through mild enzymatic hydrolysis modification. The low-glycemic whole grain raw materials are selected from one or more of oats, brown rice, and quinoa. The mild enzymatic hydrolysis modification is as follows: after cleaning and removing impurities from the low-glycemic whole grain raw materials, they are pulverized to 40-60 mesh, purified water is added at a solid-liquid ratio of 1:3, the pH is adjusted to 6.0-6.5, α-amylase is added at a concentration of 0.1%-0.3% of the mass of the low-glycemic whole grain raw materials, and the mixture is stirred at 50°C for 10-15 minutes for enzymatic hydrolysis. Then, the temperature is raised to 95°C and maintained for 10 minutes to completely inactivate the enzyme. The mixture is then passed through a 100-mesh sieve, and the filtrate is spray-dried to obtain the fast-phase particles with a particle size controlled at 10-20 mesh. The mild enzymatic hydrolysis only breaks the glycosidic bonds on the surface of the grain starch without destroying the overall starch particle structure. Only a small amount of starch on the surface is converted into small molecule dextrin, which can be quickly digested for energy, while the inner starch particles still retain their slow digestibility. The slow-phase gradient degradation gel microspheres are gradient degradation gel microspheres prepared from low-methoxyl pectin and β-glucan, encapsulating composite polyphenol-modified resistant starch. The slow-phase gradient degradation gel microspheres adopt a gradient structure design: the outer layer is mainly composed of β-glucan, the inner layer is mainly composed of low-methoxyl pectin, and the middle transition layer is composed of low-methoxyl pectin and β-glucan in a volume gradient ratio: wherein the β-glucan in the outer layer accounts for 40 wt% of the total gel mass, the low-methoxyl pectin in the inner layer accounts for 40 wt% of the total gel mass, and the gradient composite part in the middle transition layer accounts for 20 wt% of the total gel mass. The complementary layer particles are particles prepared by encapsulating slowly digestible grains with partially amylase-resistant modified oat β-glucan. The partially amylase-resistant modified oat β-glucan is prepared through the following steps: S1: Prepare a 2% (w / w) aqueous solution of crude oat β-glucan, stir and dissolve at 40°C for 2 hours, centrifuge to remove insoluble matter, gradually add anhydrous ethanol to the solution until the ethanol concentration is 3%, let stand for 12 hours, centrifuge and collect the precipitate; continue to add anhydrous ethanol to the supernatant until the ethanol concentration is 8%, let stand for 12 hours, centrifuge and collect the precipitate, combine the two precipitates, freeze dry, and obtain high molecular weight oat β-glucan with molecular weight concentrated in 100-150 kDa. S2: Prepare a 5% (w / w) aqueous solution of the high molecular weight oat β-glucan described above, add transglutaminase at an amount of 8-10 U / g of the high molecular weight oat β-glucan, adjust the pH to 6.5-7.0, react at 35°C for 40-50 min, and control the degree of crosslinking to 12%-15%. After the reaction, raise the temperature to 85°C and hold for 10 min to inactivate the transglutaminase. After freeze-drying, obtain the partially amylase-resistant modified oat β-glucan. The fast-phase particles, the slow-phase gradient-degrading gel microspheres, and the complement particles are each independent particles. After oral administration, they act sequentially during gastrointestinal digestion: the fast-phase particles first come into contact with digestive juices, releasing a small amount of rapidly energy-providing dextrin within 5-10 minutes and stimulating the satiety center; the slow-phase gradient-degrading gel microspheres then gradually degrade, continuously releasing carbohydrates 1-3 hours after the meal; the complement particles begin to degrade 3 hours after the meal, supplementing energy supply in the late postprandial period; the fast-phase particles, slow-phase gradient-degrading gel microspheres, and complement particles work synergistically to achieve stable blood glucose control throughout the postprandial period.

[0011] Further, the composite polyphenol is a mixture of chlorogenic acid and proanthocyanidins in a mass ratio of 2:1; the preparation method of the composite polyphenol-modified resistant starch is as follows: chlorogenic acid and proanthocyanidins are mixed in a mass ratio of 2:1 to prepare a 0.8 mg / mL polyphenol ethanol solution, and resistant starch is added at a solid-liquid ratio of 1 g: 10 mL. The mixture is stirred and adsorbed at 50 °C for 1 h, and the ethanol is removed by rotary evaporation and then dried to obtain the composite polyphenol-modified resistant starch. The composite polyphenol loading in the composite polyphenol-modified resistant starch is 0.7-0.9 mg / g.

[0012] Furthermore, the slow-digesting grains in the complementary layer particles are extruded modified oat grains with a particle size of 80-100 mesh, and the mass ratio of modified β-glucan to slow-digesting grains is 1:3-1:4.

[0013] Furthermore, the particle size of the fast phase layer particles is 10-20 mesh, the particle size of the slow phase layer gel microspheres is 20-40 mesh, and the particle size of the supplementary phase layer particles is 20-30 mesh.

[0014] The second objective of this invention is achieved by the following technical solution: This invention provides a method for preparing a time-release, sugar-controlled compound cereal nutritional powder, characterized by comprising the following steps: S1, Prepare the components of each phase: S11. Preparation of the fast-phase particles: Select low-glycemic whole grain raw materials; clean and remove impurities from the low-glycemic whole grain raw materials and pulverize them to 40-60 mesh; add purified water at a solid-liquid ratio of 1:3, adjust the pH to 6.0-6.5, add α-amylase, the amount of enzyme added is 0.1%-0.3% of the mass of the low-glycemic whole grain raw materials, stir and hydrolyze at 50℃ for 10-15 minutes, then raise the temperature to 95℃ and hold for 10 minutes to completely inactivate the α-amylase, pass through a 100-mesh sieve, and spray dry the filtrate at an inlet temperature of 160℃ and an outlet temperature of 80℃ to obtain the fast-phase particles with a particle size controlled at 10-20 mesh, for later use; S12. Preparation of the slow-phase gradient degradation gel microspheres: Gradient microspheres are prepared using an emulsification gelation method: The composite polyphenol-modified resistant starch is dispersed in a 2% (w / w) low-methoxyl pectin solution as the inner phase; β-glucan is prepared into a 2% (w / w) aqueous solution as the outer phase; the inner phase is added dropwise to a mixture containing food-grade emulsifier (monoglyceride, HLB) under stirring. In edible vegetable oil (3-5), after pre-forming inner phase microspheres, the β-glucan solution of the outer phase is gradually added dropwise, while food-grade calcium chloride solution (0.5 mol / L) is added dropwise to induce gel formation. The slow-phase gradient degradation gel microspheres are collected by centrifugation, washed three times with 75% food-grade ethanol and purified water, and vacuum dried at 45°C and -0.08 MPa to obtain slow-phase gradient degradation gel microspheres with a particle size of 20-40 mesh. The outer β-glucan layer accounts for 40 wt% of the total gel mass, the inner low-methoxyl pectin layer accounts for 40 wt% of the total gel mass, and the intermediate transition layer gradient composite portion accounts for 20 wt% of the total gel mass. S13. Preparation of the complementary layer particles: After cleaning and removing impurities from the slow-digesting grains (extruded modified oat grains), the grains are pulverized and passed through an 80-100 mesh sieve. The pulverized grains are then added to an aqueous solution of the high molecular weight oat β-glucan at a mass fraction of 5%. After stirring evenly, the complementary layer particles are prepared by spray granulation process. The inlet temperature is 130℃, the outlet temperature is 75℃, and the particle size is controlled at 20-30 mesh. The particles are then set aside for later use. S2. Total mixing: The prepared fast phase layer particles, slow phase layer gradient degradation gel microspheres, and supplementary phase layer particles are dry-mixed evenly according to the ratio, packaged and sterilized to obtain the time-release slow-release sugar-controlled compound grain nutritional powder.

[0015] Furthermore, in the preparation process of the slow-phase gradient degradation gel microspheres, the edible vegetable oil is one of soybean oil, rapeseed oil or corn oil, which conforms to the GB / T national standard for edible oils; after washing with 75% food-grade ethanol, it is washed three times with purified water to completely remove residual ethanol.

[0016] Furthermore, in the overall mixing step, a three-dimensional motion mixer is used for dry mixing, with a rotation speed of 10-20 rpm and a mixing time of 15-25 minutes, to ensure that the fast phase layer particles, the slow phase layer gradient degradation gel microspheres, and the complementary phase layer particles are uniformly dispersed without damaging the particle structure.

[0017] Furthermore, in the packaging sterilization step, microwave sterilization or irradiation sterilization is used, with microwave sterilization power of 800W and time of 3 minutes, or irradiation sterilization dose of 5-8kGy.

[0018] The second objective of this invention is achieved by the following technical solution: This invention provides the application of a time-release, sugar-controlled compound cereal nutritional powder in the preparation of instant cereal products.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Invented and designed three-phase synchronous phase-separated glucose control system: The fast phase layer uses mildly enzymatically modified low glycemic whole grain raw materials to release a small amount of fast-release dextrin in advance and stimulate the satiety center, which can relieve hunger in advance without causing a sudden rise in blood sugar; the slow phase layer gradient degradation gel microspheres match the insulin secretion window and assist polyphenols in glucose control; the supplementary phase layer particles use precisely controllable modified amylase-resistant oat β-glucan to achieve delayed energy release 3-4 hours after meals, which solves the technical pain points of insufficient energy supply in the late postprandial period and easy reactive hypoglycemia in traditional glucose control products.

[0020] 2. This invention employs a graded alcohol precipitation combined with limited cross-linking modification method for oat β-glucan, which precisely controls the degree of enzyme resistance. Only high molecular weight β-glucan with a cross-linking degree of 12-15% can achieve a release window of 3-4 hours after a meal. The parameter control is clear and repeatable, the production process is stable, and it is suitable for industrial production.

[0021] 3. Efficacy verification shows that the product of this invention can stabilize blood glucose in the normal range 4 hours after a meal, reduce the incidence of reactive hypoglycemia from 32% to 0, and relieve hunger 10-15 minutes earlier, improving the consumption experience for people with blood sugar control. It is suitable for long-term consumption by people with impaired glucose tolerance and those who need to control blood sugar and lose fat. Detailed Implementation

[0022] The present invention will now be further described in conjunction with specific embodiments. It should be noted that, without conflict, the embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0023] Example 1 This embodiment provides a time-release, slow-release, sugar-controlled compound cereal nutritional powder, comprising the following components by weight: 10 parts of fast phase layer particles, 35 parts of slow phase layer gradient degradation gel microspheres, and 40 parts of supplementary phase layer particles.

[0024] Among them, the fast phase layer particles are prepared from low glycemic whole grain raw materials through mild enzymatic hydrolysis modification. They are made from oat whole grains and do not contain fast-digesting starch, such as refined rice or flour. After the fast phase layer particles enter the stomach, they can release soluble dextrin within 5-10 minutes, which can stimulate the satiety center in advance and provide a small amount of energy, relieving hunger 10-15 minutes in advance without causing a sudden rise in blood sugar. The slow-phase gradient degradation gel microspheres are gradient degradation gel microspheres prepared from low-methoxyl pectin (LMP) and β-glucan, encapsulating polyphenol-modified resistant starch. The slow-phase gradient degradation gel microspheres adopt a gradient structure design: the outer layer is mainly composed of β-glucan (rapid degradation), the inner layer is mainly composed of low-methoxyl pectin (slow degradation), and the middle transition layer is composed of low-methoxyl pectin and β-glucan in a volume gradient ratio to achieve different degradation rates, matching the complete time window of insufficient insulin secretion, while the polyphenols help inhibit sugar decomposition. Among them, the outer layer of β-glucan accounts for 40 wt% of the total gel mass, the inner layer of low-methoxyl pectin accounts for 40 wt% of the total gel mass, and the middle transition layer of gradient composite part accounts for 20 wt% of the total gel mass. The compound polyphenol is a mixture of chlorogenic acid and proanthocyanidins in a mass ratio of 2:1. The preparation method of the compound polyphenol-modified resistant starch is as follows: chlorogenic acid and proanthocyanidins are mixed in a mass ratio of 2:1 to prepare a 0.8 mg / mL polyphenol ethanol solution. Resistant starch is added at a solid-liquid ratio of 1 g:10 mL, stirred and adsorbed at 50 °C for 1 h, the ethanol is removed by rotary evaporation, and then dried to obtain the compound polyphenol-modified resistant starch. The compound polyphenol loading in the modified resistant starch is 0.7-0.9 mg / g. The complement layer particles are prepared by encapsulating slow-digesting grains with partially amylase-resistant modified oat β-glucan. The partially amylase-resistant modified oat β-glucan degrades slowly only 3 hours after a meal, releasing carbohydrates to supplement energy supply in the late postprandial period and prevent blood sugar from dropping too quickly. The slow-digesting grains in the complement layer particles are extruded modified oat grains with a particle size of 80-100 mesh, and the mass ratio of modified β-glucan to slow-digesting grains is 1:3-1:4. This embodiment provides a method for preparing a time-release, sugar-controlled compound cereal nutritional powder, comprising the following steps: S1, Prepare the components of each phase: S11. Preparation of fast-phase particles: Whole oat grains were selected as raw materials. After cleaning and removing impurities, the grains were pulverized to 40 mesh using a hammer mill. Purified water was added at a solid-liquid ratio of 1:3 (w / v). The pH was adjusted to 6.0 with 1 mol / L citric acid solution. The amount of enzyme added was 0.1% of the mass of oats. The stirring paddle was turned on and stirred at 200 rpm. The mixture was heated in a water bath to 50°C and kept at a constant temperature for 10 minutes for enzymatic hydrolysis. After the enzymatic hydrolysis, the temperature was immediately raised to 95°C and held for 10 minutes to completely inactivate the enzyme. The mixture was then passed through a 100-mesh vibrating sieve, and the filtrate was collected. The filtrate was dried in a spray dryer with an inlet temperature of 160°C, an outlet temperature of 80°C, and a feed flow rate of 15 mL / min to obtain fast-phase particles with a particle size of 10-20 mesh and a moisture content of ≤5%. The particles were then set for later use. S12, Preparation of Gradient Degradation Gel Microspheres in Slow-Phase Layers: Preparation of polyphenol-modified resistant starch: Chlorogenic acid (purity ≥95%, purchased from Shaanxi Huike Plant Development Co., Ltd.) and proanthocyanidins (purity ≥95%, grape seed source, purchased from Tianjin Jianfeng Co., Ltd.) were mixed at a mass ratio of 2:1, and anhydrous ethanol was added to prepare a polyphenol ethanol solution of 0.8 mg / mL; resistant starch (RS3 type, purchased from National Starch Industry (Shanghai) Co., Ltd.) was added at a solid-liquid ratio of 1 g:10 mL, and the mixture was placed in a 50℃ water bath and stirred at 150 rpm for 1 h for adsorption. Then, the ethanol was removed by rotary evaporator at 50℃ and -0.09 MPa, and dried in a vacuum drying oven at 45℃ to constant weight to obtain polyphenol-modified resistant starch. The polyphenol loading was determined by HPLC to be 0.8 mg / g. Preparation of gradient degradation gel microspheres: The above-mentioned polyphenol-modified resistant starch was dispersed in a 2% (w / w) aqueous solution of low-methoxyl pectin (LMP, DE value 30%-35%, purchased from CP Kelco) and ultrasonically dispersed for 10 minutes as the inner phase; oat β-glucan (purity ≥80%, purchased from Xi'an Tianyi Company) was prepared into a 2% (w / w) aqueous solution as the outer phase; 300 mL of edible vegetable oil (soybean oil, conforming to GB / T) was added to a 500 mL three-necked flask. 1535 standard) and 3g monoglyceride (HLB4.0, food grade, purchased from Guangzhou Meichen Company) were placed in a 40℃ water bath and stirred at 400rpm. The internal phase solution was added dropwise to the oil phase at a flow rate of 2mL / min to pre-form internal phase microspheres. Subsequently, the external phase β-glucan solution was added dropwise at a flow rate of 1mL / min, while food-grade calcium chloride solution (concentration 0.5mol / L) was added dropwise at a flow rate of 0.5mL / min to induce gel cross-linking. After the addition was completed, stirring was continued for 30 minutes, and the mixture was centrifuged. Microspheres were collected and washed twice with 75% food-grade ethanol and three times with purified water at 3000 rpm for 5 minutes. After each washing, the microspheres were collected by centrifugation. The washed microspheres were placed in a vacuum drying oven and dried at 45°C and a vacuum of -0.08 MPa until the moisture content was ≤5%, resulting in gradient-degraded gel microspheres with a particle size of 20-40 mesh. Microscopic observation confirmed that the outer β-glucan layer accounted for 40 wt% of the total gel mass, the inner low-methoxyl pectin layer accounted for 40 wt%, and the gradient composite transition layer accounted for 20 wt%. These were then set aside for later use.

[0025] S13. Preparation of the complementary layer particles: Preparation of partially amylase-resistant modified oat β-glucan: Crude oat β-glucan (purity ≥70%, purchased from Xi'an Tianyi Biotechnology Co., Ltd.) was prepared into a 2% (w / w) aqueous solution. After dissolving by stirring at 40℃ for 2 hours, the insoluble matter was removed by centrifugation at 4000 rpm for 15 minutes. Anhydrous ethanol was slowly added to the supernatant while stirring until the final ethanol concentration was 3%. After standing for 12 hours, the first precipitate was collected by centrifugation at 4000 rpm for 15 minutes. Anhydrous ethanol was added to the supernatant until the final ethanol concentration was 8%. After standing for 12 hours, the second precipitate was collected by centrifugation at 4000 rpm for 15 minutes. The two precipitates were combined, reconstituted with purified water, and then freeze-dried at a pre-freezing temperature of -40℃, a vacuum degree ≤10 Pa, and a drying time of 24 hours to obtain high molecular weight oat β-glucan with a molecular weight concentrated in the range of 100-150 kDa. The weight average molecular weight was determined to be 128 kDa by gel permeation chromatography (GPC). The above-mentioned high molecular weight oat β-glucan was prepared into a 5% (w / w) aqueous solution. Transglutaminase (enzyme activity 100 U / g, purchased from Taixing Dongsheng Biotechnology Co., Ltd.) was added at a concentration of 8 U / g of β-glucan. The pH was adjusted to 6.5 with 0.1 mol / L phosphate buffer and placed in a 35°C water bath shaker at 100 rpm for 40 minutes. After the reaction, the temperature was immediately raised to 85°C and held for 10 minutes to inactivate the enzyme. After freeze-drying, partially amylase-resistant modified oat β-glucan was obtained. The cross-linking degree was determined (using the trinitrobenzenesulfonic acid method) to be 12%. Preparation of the complementary layer particles: After cleaning and removing impurities, the extruded modified oat grains (extrusion temperature 120℃, screw speed 150rpm, purchased from Guilin Ximai Biotechnology Development Co., Ltd.) were pulverized using a universal pulverizer and passed through an 80-mesh standard sieve to obtain slow-digesting oat flour with a particle size of 80-100 mesh; the above-mentioned partially amylase-resistant modified oat β-glucan was prepared into a 5% (w / w) aqueous solution, and added to the slow-digesting oat flour at a mass ratio of partially amylase-resistant modified oat β-glucan to slow-digesting oat flour of 1:3. The mixture was stirred at 200rpm for 30 minutes until uniformly dispersed, and then granulated using a spray granulator with an inlet temperature of 130℃, an outlet temperature of 75℃, an atomization pressure of 0.3MPa, and a feed flow rate of 20mL / min to obtain complementary layer particles with a particle size of 20-30 mesh and a moisture content of ≤5%, which were then set aside. S2. Overall Mixing: Add 10 parts of the prepared fast phase layer particles, 35 parts of the slow phase layer gradient degradation gel microspheres, and 40 parts of the complementary phase layer particles to a three-dimensional motion mixer. Set the speed to 15 rpm and the mixing time to 20 minutes to ensure that the fast phase layer particles, slow phase layer gradient degradation gel microspheres, and complementary phase layer particles are evenly dispersed. Distribute the mixed material into aluminum-plastic composite bags in 30g portions, sterilize them using microwave, and then seal them at 800W for 3 minutes to obtain a time-release, sugar-controlled compound grain nutritional powder.

[0026] Tests showed that the product in this embodiment underwent in vitro simulated gastrointestinal digestion experiments as follows: 7.2±0.9% carbohydrate release in the stomach during 0-2 hours, 28.5±3.0% in the small intestine during 2-4 hours, 56.3±4.1% after 3-4 hours postprandial (3-4 hours of small intestine digestion), and a total release rate of 92.8±2.3% 6 hours after digestion, meeting the design requirements. Human trials (10 volunteers with impaired glucose tolerance, aged 35-55 years, consuming 50g of sample) showed the following results: average blood glucose 5.0±0.3mmol / L 4 hours postprandial, 0% (0 / 10) of reactive hypoglycemia, average onset of hunger 162±10 minutes, and hunger relief 12 minutes earlier, meeting expectations.

[0027] Example 2 This embodiment provides a time-release, slow-release, sugar-controlled compound cereal nutritional powder, comprising the following components by weight: 12 parts of fast phase layer particles, 40 parts of slow phase layer gradient degradation gel microspheres, and 35 parts of supplementary phase layer particles.

[0028] This embodiment provides a method for preparing a time-release, sugar-controlled compound cereal nutritional powder, comprising the following steps: S1, Prepare the components of each phase: S11. Preparation of fast-phase particles: Whole oat grains are selected as raw materials. After cleaning and removing impurities, they are pulverized to 50 mesh. Purified water is added at a solid-liquid ratio of 1:3, and the pH is adjusted to 6.2. Heat-resistant α-amylase (enzyme activity 5000U / g) is added at a rate of 0.2% of the oat mass. The mixture is stirred at 50℃ for 12 minutes to hydrolyze the enzyme. The temperature is then raised to 95℃ and held for 10 minutes to inactivate the enzyme. The mixture is passed through a 100-mesh sieve, and the filtrate is spray-dried at an inlet temperature of 160℃ and an outlet temperature of 80℃ to obtain fast-phase particles with a particle size of 10-20 mesh, which are then set aside for use.

[0029] S12. Preparation of Gradient Degradation Gel Microspheres: The preparation method of the composite polyphenol-modified resistant starch is the same as in Example 1, with a polyphenol loading of 0.8 mg / g; the preparation method of the gradient gel microspheres is the same as in Example 1, with edible vegetable oil as the oil phase, monoglyceride as the emulsifier, food-grade calcium chloride to induce gelation, washing with 75% food-grade ethanol and purified water, and vacuum drying at 45℃ (vacuum degree -0.08 MPa) to obtain 20-40 mesh microspheres, with an outer layer of 40 wt% β-glucan, an inner layer of 40 wt% LMP, and a transition layer of 20 wt%.

[0030] S13. Preparation of the supplementary phase layer particles: Crude oat β-glucan was subjected to a 3%-8% gradient alcohol precipitation to obtain 100-150kDa high molecular weight β-glucan. 9U / g transglutaminase was added, and the reaction was carried out at pH 6.8 and 35℃ for 45 minutes, controlling the degree of cross-linking at 13.5%. The enzyme was inactivated at 85℃ for 10 minutes, and the mixture was freeze-dried to obtain modified β-glucan. The extruded modified oat grains were pulverized through an 80-mesh sieve and mixed with the modified β-glucan at a mass ratio of 1:3.5. The mixture was then added to a 5% (w / w) modified β-glucan aqueous solution and stirred evenly. The mixture was then spray-granulated (inlet temperature 130℃, outlet temperature 75℃) to obtain 20-30 mesh particles for later use.

[0031] S2. Total Mixing: Add 12 parts of fast phase layer particles, 40 parts of slow phase layer gradient degradation gel microspheres, and 35 parts of supplementary phase layer particles to a three-dimensional motion mixer and mix at 15 rpm for 20 minutes. Dispense into 30g bags and microwave sterilize (800W, 3 minutes) to obtain the finished product.

[0032] Testing showed that the product in this embodiment released 8.5±1.0% of carbohydrates in 0-2 hours after in vitro digestion, 32.5±3.5% in 2-4 hours, 54.2±4.5% in 3-4 hours after a meal, and a total release rate of 93.5±2.3% in 6 hours. In human trials, the average blood glucose level 4 hours after a meal was 5.2±0.3 mmol / L, the incidence of reactive hypoglycemia was 0% (0 / 10), the average time to hunger onset was 165±12 minutes, and the feeling of hunger was relieved 15 minutes earlier, which met expectations.

[0033] Example 3 This embodiment provides a time-release, slow-release, sugar-controlled compound cereal nutritional powder, comprising the following components by weight: 15 parts of fast phase layer particles, 45 parts of slow phase layer gradient degradation gel microspheres, and 30 parts of supplementary phase layer particles.

[0034] This embodiment provides a method for preparing a time-release, sugar-controlled compound cereal nutritional powder, comprising the following steps: S1, Prepare the components of each phase: S11. Preparation of fast-phase particles: Quinoa whole grains are selected as raw materials. After cleaning and removing impurities, the grains are pulverized to 60 mesh. Purified water is added at a solid-liquid ratio of 1:3, and the pH is adjusted to 6.5. Heat-resistant α-amylase (enzyme activity 5000U / g) is added at a rate of 0.3% of the quinoa mass. The mixture is stirred at 50℃ for 15 minutes to hydrolyze the enzyme. The temperature is then raised to 95℃ and held for 10 minutes to inactivate the enzyme. The mixture is passed through a 100-mesh sieve, and the filtrate is spray-dried (inlet temperature 160℃, outlet temperature 80℃) to obtain fast-phase particles with a particle size of 10-20 mesh for later use.

[0035] S12. Preparation of gradient degradation gel microspheres in slow phase layer: The preparation method of composite polyphenol modified resistant starch is the same as in Example 1, with a polyphenol loading of 0.9 mg / g; the preparation method of gradient gel microspheres is the same as in Example 1, resulting in 20-40 mesh microspheres with an outer layer of 40 wt% β-glucan, an inner layer of 40 wt% LMP, and a transition layer of 20 wt%.

[0036] S13. Preparation of Complementary Layer Particles: Crude oat β-glucan was subjected to a 3%-8% gradient alcohol precipitation to obtain 100-150kDa high molecular weight β-glucan. 10U / g transglutaminase was added, and the reaction was carried out at pH 7.0 and 35℃ for 50 minutes, controlling the degree of cross-linking at 15%. The enzyme was inactivated at 85℃ for 10 minutes, and the mixture was freeze-dried to obtain modified β-glucan. The extruded modified oat grains were crushed and passed through a 100-mesh sieve, and mixed with modified β-glucan at a mass ratio of 1:4. The mixture was then added to a 5% (w / w) modified β-glucan aqueous solution and stirred evenly. The mixture was then spray-granulated (inlet temperature 130℃, outlet temperature 75℃) to obtain 20-30 mesh particles for later use.

[0037] S2. Total Mixing: Add 15 parts of fast phase layer particles, 45 parts of slow phase layer gradient degradation gel microspheres, and 30 parts of supplementary phase layer particles to a three-dimensional motion mixer and mix at 15 rpm for 20 minutes. Dispense into 30g bags and microwave sterilize (800W, 3 minutes) to obtain the finished product.

[0038] Testing showed that the product in this embodiment released 9.5±1.1% of carbohydrates in 0-2 hours after in vitro digestion, 34.2±3.8% in 2-4 hours, 53.5±4.2% in 3-4 hours after a meal, and a total release rate of 91.8±2.5% in 6 hours. In human trials, the average blood glucose level 4 hours after a meal was 5.4±0.4 mmol / L, the incidence of reactive hypoglycemia was 0% (0 / 10), the average time to hunger onset was 168±14 minutes, and the feeling of hunger was relieved 15 minutes earlier, which met expectations.

[0039] Example 4 This embodiment provides a time-release, slow-release, sugar-controlled compound cereal nutritional powder, comprising the following components by weight: 10 parts of fast phase layer particles, 45 parts of slow phase layer gradient degradation gel microspheres, and 32 parts of supplementary phase layer particles.

[0040] This embodiment provides a method for preparing a time-release, sugar-controlled compound cereal nutritional powder, comprising the following steps: S1, Prepare the components of each phase: S11. Preparation of fast-phase particles: Brown rice whole grains are selected as raw materials. After cleaning and removing impurities, the grains are pulverized to 40 mesh. Purified water is added at a solid-liquid ratio of 1:3, and the pH is adjusted to 6.0. Heat-resistant α-amylase (enzyme activity 5000U / g) is added at a rate of 0.1% of the brown rice mass. The grains are enzymatically hydrolyzed at 50℃ for 10 minutes, and then inactivated at 95℃ for 10 minutes. The grains are then passed through a 100-mesh sieve and spray-dried (inlet temperature 160℃, outlet temperature 80℃) to obtain fast-phase particles with a particle size of 10-20 mesh for later use.

[0041] S12. Preparation of gradient degradation gel microspheres in slow phase layer: The loading of resistant starch polyphenol modified with composite polyphenol is 0.8 mg / g; the gradient gel microspheres are prepared by the same method as in Example 1, and 20-40 mesh microspheres are obtained.

[0042] S13. Preparation of the supplementary phase layer particles: Crude oat β-glucan was subjected to a 3%-8% gradient alcohol precipitation to obtain 100-150kDa high molecular weight β-glucan. 8U / g transglutaminase was added, and the reaction was carried out at pH 6.5 and 35℃ for 40 minutes, controlling the degree of cross-linking at 12%. The enzyme was inactivated at 85℃ for 10 minutes, and then freeze-dried to obtain modified β-glucan. The extruded modified oat grains were crushed and passed through an 80-mesh sieve, and mixed with the modified β-glucan at a mass ratio of 1:3. The mixture was then spray-granulated (inlet temperature 130℃, outlet temperature 75℃) to obtain 20-30 mesh particles for later use.

[0043] S2. Total Mixing: Add 10 parts of fast phase layer particles, 45 parts of slow phase layer gradient degradation gel microspheres, and 32 parts of supplementary phase layer particles to a three-dimensional motion mixer and mix at 15 rpm for 20 minutes. Dispense into 30g bags and microwave sterilize (800W, 3 minutes) to obtain the finished product.

[0044] Testing showed that the product in this embodiment released 7.0±0.8% of carbohydrates in 0-2 hours after in vitro digestion, 31.5±3.2% in 2-4 hours, 55.8±4.0% in 3-4 hours after a meal, and a total release rate of 92.5±2.1% in 6 hours. In human trials, the average blood glucose level 4 hours after a meal was 5.1±0.3 mmol / L, the incidence of reactive hypoglycemia was 0% (0 / 10), the average time to hunger onset was 160±11 minutes, and the feeling of hunger was relieved 10 minutes earlier, which met expectations.

[0045] Example 5 This embodiment provides a time-release, slow-release, sugar-controlled compound cereal nutritional powder, comprising the following components by weight: 15 parts of fast phase layer particles, 35 parts of slow phase layer gradient degradation gel microspheres, and 38 parts of supplementary phase layer particles.

[0046] This embodiment provides a method for preparing a time-release, sugar-controlled compound cereal nutritional powder, comprising the following steps: S1, Prepare the components of each phase: S11. Preparation of fast-phase particles: Oat whole grains and quinoa whole grains are mixed at a mass ratio of 1:1 as raw materials. After cleaning and removing impurities, the mixture is pulverized to 60 mesh. Purified water is added at a solid-liquid ratio of 1:3, and the pH is adjusted to 6.5. Heat-resistant α-amylase (enzyme activity 5000U / g) is added at a concentration of 0.3% of the mass of the mixed grains. The mixture is enzymatically hydrolyzed at 50℃ for 15 minutes, and then inactivated at 95℃ for 10 minutes. The mixture is then passed through a 100-mesh sieve and spray-dried (inlet temperature 160℃, outlet temperature 80℃) to obtain fast-phase particles with a particle size of 10-20 mesh for later use.

[0047] S12. Preparation of gradient degradation gel microspheres in slow phase layer: The loading of resistant starch polyphenol modified with composite polyphenol is 0.7 mg / g; the gradient gel microspheres are prepared by the same method as in Example 1, and 20-40 mesh microspheres are obtained.

[0048] S13. Preparation of supplementary phase layer particles: Crude oat β-glucan was subjected to 3%-8% gradient alcohol precipitation to obtain 100-150kDa high molecular weight β-glucan. 10U / g transglutaminase was added, and the reaction was carried out at pH 7.0 and 35℃ for 50 minutes, controlling the degree of cross-linking at 14%. The enzyme was inactivated at 85℃ for 10 minutes, and the mixture was freeze-dried to obtain modified β-glucan. The extruded modified oat grains were crushed and passed through a 100-mesh sieve, and mixed with the modified β-glucan at a mass ratio of 1:4. The mixture was then spray-granulated (inlet temperature 130℃, outlet temperature 75℃) to obtain 20-30 mesh particles for later use.

[0049] S2. Total Mixing: Add 15 parts of fast phase layer particles, 35 parts of slow phase layer gradient degradation gel microspheres, and 38 parts of supplementary phase layer particles to a three-dimensional motion mixer and mix at 15 rpm for 20 minutes. Dispense into 30g bags and microwave sterilize (800W, 3 minutes) to obtain the finished product.

[0050] Testing showed that the product in this embodiment released 9.8±1.2% of carbohydrates in 0-2 hours after in vitro digestion, 29.8±3.0% in 2-4 hours, 57.5±4.3% in 3-4 hours after a meal, and a total release rate of 93.2±2.4% in 6 hours. In human trials, the average blood glucose level 4 hours after a meal was 5.3±0.3 mmol / L, the incidence of reactive hypoglycemia was 0% (0 / 10), the average time to hunger onset was 170±13 minutes, and the feeling of hunger was relieved 15 minutes earlier, which met expectations.

[0051] Comparative Example 1: The β-glucan in the complementary phase layer was not modified for enzyme resistance. Ungraded and uncrosslinked ordinary oat β-glucan was used to directly encapsulate slow-digesting grains. The remaining components and processes were the same as in Example 1.

[0052] Comparative Example 2: The degree of crosslinking of the modified β-glucan was 10% (lower than the 12-15% range required by this invention), and the remaining parameters and processes were the same as in Example 1.

[0053] Comparative Example 3: The degree of crosslinking of the modified β-glucan was 20% (higher than the 12-15% range required by this invention), and the remaining parameters and processes were the same as those in Example 1.

[0054] Comparative Example 4: No supplementary phase layer was added, but the supplementary phase layer was replaced with an equal amount of ordinary slow-release resistant starch. The remaining components and processes were the same as in Example 1, i.e., the existing traditional double-layer slow-release sugar-controlled cereal powder.

[0055] Comparative Example 5: No fast phase layer was added, and the fast phase layer was replaced with an equal amount of unhydrolyzed whole grain particles, i.e., whole oat grains were ground to 50 mesh and not treated with α-amylase. The remaining components and processes were the same as in Example 1.

[0056] Experimental Example 1 In vitro simulated gastrointestinal digestion experiment Referring to the in vitro simulated gastrointestinal digestion method published in the *Chinese Journal of Food Science* in 2022, gastric digestion (0-2 h, pH 2.0, 37 °C, containing pepsin) and small intestinal digestion (2-6 h, pH 6.8, 37 °C, containing 100 U / mL α-amylase) were simulated respectively. The carbohydrate release rate at different time points was measured, and the results are shown in Table 1. Table 1. In vitro carbohydrate release rate (%) of different samples ; As can be seen from the results in Table 1, the carbohydrate release patterns of Examples 1-5 of the present invention all meet the design requirements: 7.0%-9.8% of carbohydrates are released in the stomach during 0-2 hours of digestion (of which the fast phase layer contributes about 5-7% of the fast energy-providing dextrin), 28.5%-34.2% is released during 2-4 hours (2 hours before small intestine), and 53.5%-57.5% of the total carbohydrates are released 3-4 hours after the meal, achieving precise delayed energy release; Comparative Example 1 used unmodified β-glucan, and Comparative Example 2 had insufficient cross-linking. Both showed insufficient enzyme resistance, premature release of carbohydrates, excessive release in the early postprandial period, and insufficient carbohydrate release 3-4 hours after the meal. Comparative Example 3 had excessive cross-linking, resulting in excessive enzyme resistance and a total carbohydrate release rate of less than 45%, which could not provide effective energy. Comparative Example 4 did not add the complementary phase layer of this invention, and the carbohydrate release 3-4 hours after the meal was only 18.6%, which was insufficient for energy supply. Comparative Example 5 did not add the fast phase layer particles for enzymatic hydrolysis modification, and the gastric digestion released only 4.2%, which lacked early rapid energy supply and satiety stimulation.

[0057] Experiment Example 2 Human food trials One hundred volunteers with impaired glucose tolerance, aged 35-55 years, were recruited and divided into 10 groups of 10 participants each. Each group consumed an equal amount (50g) of different samples. Fasting blood glucose and average 4-hour postprandial blood glucose were measured. The incidence of reactive hypoglycemia (blood glucose below 3.9 mmol / L, accompanied by hunger and dizziness) 4-hour postprandial was calculated. The onset time of hunger was also recorded (a score ≥2 points higher than the fasting baseline hunger score was considered as significant hunger). The results are shown in Table 2. Table 2 Results of human trials on different samples ; As shown in Table 2, the average blood glucose levels 4 hours after meals in Examples 1-5 of this invention were all stable in the range of 4.8-5.6 mmol / L, and the incidence of reactive hypoglycemia was 0%. The mild enzymatic modification of the fast phase layer delayed the onset of hunger to 160-170 minutes, which was 22-32 minutes later than that of the control example 5 without the fast phase layer, and the effect of relieving hunger earlier was significant. Comparative Examples 1 and 2, due to insufficient enzyme resistance, experienced premature carbohydrate release, resulting in insufficient energy supply and low blood glucose levels 4 hours postprandial. Comparative Example 3, with excessive cross-linking and insufficient carbohydrate release, still exhibited a certain proportion of hypoglycemia. Comparative Example 4, without the addition of the complementary phase layer of this invention, showed an average blood glucose level of only 3.9 mmol / L 4 hours postprandial, with a hypoglycemia incidence rate of 32%. Comparative Example 5, without the addition of the fast phase layer for enzymatic modification, showed acceptable blood glucose control, but the onset of hunger occurred 27 minutes earlier, demonstrating the important value of the fast phase layer in providing early energy and stimulating satiety.

[0058] Experimental Example 3 Experiment on optimization of enzymatic hydrolysis parameters of fast phase layer To accurately determine the process parameters for mild enzymatic hydrolysis of the fast phase layer, experiments were conducted to determine the enzyme dosage and hydrolysis time gradient. The dextrin release rate during gastric digestion (0-30 minutes) was used as the indicator. The results are shown in Table 3. Table 3 Optimization of enzymatic hydrolysis parameters for the fast phase layer ; The results showed that when the enzyme addition was 0.1%-0.3% and the enzymatic hydrolysis time was 10-15 minutes, the dextrin release rate was controlled at 4.5%-8.2% within 0-30 minutes, which could stimulate satiety in advance without causing a sudden rise in blood sugar. Below this range, the stimulation was insufficient, and above this range, the slow digestion characteristics were lost.

[0059] Experiment Example 4 In vitro pre-validation experiment of complementary layer parameters To accurately determine the crosslinking degree range of modified β-glucan in the complement layer, a crosslinking degree gradient experiment was set up: modified β-glucan with crosslinking degrees of 8%, 10%, 12%, 13.5%, 15%, 18%, and 20% were prepared respectively. Complement layer particles were prepared according to the same process, and in vitro simulated gastrointestinal digestion experiments were conducted. The carbohydrate release rate at 3-4 hours postprandial (3-4 hours of small intestinal digestion) and the total release rate at 6 hours were measured. The results are shown in Table 4. Table 4. In vitro release performance of complement layers with different degrees of crosslinking ; As shown in Table 4, within the crosslinking degree range of 12-15%, the release rate is stable at 52-57% 3-4 hours after the meal, and the total release rate is ≥89% after 6 hours, which precisely matches the design window; when the crosslinking degree is below 12%, too much is released prematurely, and when it is above 15%, the release is insufficient, which verifies the scientific nature and necessity of the crosslinking degree range of the present invention.

[0060] Experimental Example 5 Experiment on optimization of the ratio of fast phase layer particles, slow phase layer gradient degradation gel microspheres and complementary phase layer particles To verify the effectiveness of the ratio range of fast-phase layer particles, slow-phase layer gradient degradation gel microspheres, and complement layer particles, a gradient experiment was set up with different ratios of fast-phase layer particles, slow-phase layer gradient degradation gel microspheres, and complement layer particles. The 4-hour postprandial blood glucose maintenance level and the time to hunger onset were used as evaluation indicators. The results are shown in Table 5. Table 5. Effect of the ratio of the three phases on the blood sugar control effect. ; The results showed that within the ratio of 10-15 parts fast phase, 35-45 parts slow phase, and 30-40 parts complement phase, postprandial blood glucose remained stable at 4.8-5.6 mmol / L 4 hours after the meal, and the hunger sensation appeared within 160-170 minutes, with a balanced effect on blood sugar control and satiety relief. Outside this range, problems such as insufficient satiety in the early stage, poor blood sugar control in the middle stage, or insufficient energy supply in the late stage occurred.

[0061] Experimental Example 6 Gradient degradation verification of the slow phase layer Gradient gel microspheres with outer β-glucan contents of 20%, 40%, and 60% were prepared, respectively, and in vitro digestion experiments were conducted. The carbohydrate release rates at 2-4 h and 3-4 h were measured. The results are shown in Table 6. Table 6. Influence of the gradient structure of the buffer layer on release performance ; The results showed that when the outer β-glucan content was 40%, about 32.5% was released in 2-4 hours and about 54.2% in 3-4 hours, forming a good connection with the complement layer and achieving stable energy supply throughout the entire post-meal cycle.

[0062] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A time-release, slow-release, sugar-controlled compound grain nutritional powder, characterized in that, Includes the following components by weight: 10-15 parts of fast phase layer particles, 35-45 parts of slow phase layer gradient degradation gel microspheres, and 30-40 parts of supplementary phase layer particles; The fast-phase particles are prepared from low-glycemic whole grain raw materials through mild enzymatic hydrolysis modification. The low-glycemic whole grain raw materials are selected from one or more of oats, brown rice, and quinoa. The mild enzymatic hydrolysis modification is as follows: after cleaning and removing impurities from the low-glycemic whole grain raw materials, they are pulverized to 40-60 mesh, purified water is added at a solid-liquid ratio of 1:3, the pH is adjusted to 6.0-6.5, α-amylase is added at a concentration of 0.1%-0.3% of the mass of the low-glycemic whole grain raw materials, and the mixture is stirred at 50°C for 10-15 minutes for enzymatic hydrolysis. Then, the temperature is raised to 95°C and maintained for 10 minutes to completely inactivate the enzyme. The mixture is then passed through a 100-mesh sieve, and the filtrate is spray-dried to obtain the fast-phase particles with a particle size controlled at 10-20 mesh. The mild enzymatic hydrolysis only breaks the glycosidic bonds on the surface of the grain starch without destroying the overall starch particle structure. Only a small amount of starch on the surface is converted into small molecule dextrin, which can be quickly digested for energy, while the inner starch particles still retain their slow digestibility. The slow-phase gradient degradation gel microspheres are gradient degradation gel microspheres prepared from low-methoxyl pectin and β-glucan, encapsulating composite polyphenol-modified resistant starch. The slow-phase gradient degradation gel microspheres adopt a gradient structure design: the outer layer is mainly composed of β-glucan, the inner layer is mainly composed of low-methoxyl pectin, and the middle transition layer is composed of low-methoxyl pectin and β-glucan in a volume gradient ratio: wherein the β-glucan in the outer layer accounts for 40 wt% of the total gel mass, the low-methoxyl pectin in the inner layer accounts for 40 wt% of the total gel mass, and the gradient composite part in the middle transition layer accounts for 20 wt% of the total gel mass. The complementary layer particles are particles prepared by encapsulating slowly digestible grains with partially amylase-resistant modified oat β-glucan. The partially amylase-resistant modified oat β-glucan is prepared through the following steps: S1: Prepare a 2% (w / w) aqueous solution of crude oat β-glucan, stir and dissolve at 40°C for 2 hours, centrifuge to remove insoluble matter, gradually add anhydrous ethanol to the solution until the ethanol concentration is 3%, let stand for 12 hours, centrifuge and collect the precipitate; continue to add anhydrous ethanol to the supernatant until the ethanol concentration is 8%, let stand for 12 hours, centrifuge and collect the precipitate, combine the two precipitates, freeze dry, and obtain high molecular weight oat β-glucan with molecular weight concentrated in 100-150 kDa. S2: Prepare a 5% (w / w) aqueous solution of the high molecular weight oat β-glucan described above, add transglutaminase at an amount of 8-10 U / g of the high molecular weight oat β-glucan, adjust the pH to 6.5-7.0, react at 35°C for 40-50 min, and control the degree of crosslinking to 12%-15%. After the reaction, raise the temperature to 85°C and hold for 10 min to inactivate the transglutaminase. After freeze-drying, obtain the partially amylase-resistant modified oat β-glucan. The fast-phase particles, the slow-phase gradient-degrading gel microspheres, and the complement particles are each independent particles. After oral administration, they act sequentially during gastrointestinal digestion: the fast-phase particles first come into contact with digestive juices, releasing a small amount of rapidly energy-providing dextrin within 5-10 minutes and stimulating the satiety center; the slow-phase gradient-degrading gel microspheres then gradually degrade, continuously releasing carbohydrates 1-3 hours after the meal; the complement particles begin to degrade 3 hours after the meal, supplementing energy supply in the late postprandial period; the fast-phase particles, slow-phase gradient-degrading gel microspheres, and complement particles work synergistically to achieve stable blood glucose control throughout the postprandial period.

2. The time-release, slow-release, sugar-controlled compound grain nutritional powder as described in claim 1, characterized in that, The composite polyphenol is a mixture of chlorogenic acid and proanthocyanidins in a mass ratio of 2:

1. The preparation method of the composite polyphenol-modified resistant starch is as follows: chlorogenic acid and proanthocyanidins are mixed in a mass ratio of 2:1 to prepare a 0.8 mg / mL polyphenol ethanol solution. Resistant starch is added at a solid-liquid ratio of 1 g: 10 mL, stirred and adsorbed at 50 °C for 1 h, and the ethanol is removed by rotary evaporation and then dried to obtain the composite polyphenol-modified resistant starch. The composite polyphenol loading in the composite polyphenol-modified resistant starch is 0.7-0.9 mg / g.

3. The time-release, slow-release, sugar-controlled compound grain nutritional powder as described in claim 1, characterized in that, The slow-digesting grains in the complementary layer particles are extruded modified oat grains with a particle size of 80-100 mesh, and the mass ratio of modified β-glucan to slow-digesting grains is 1:3-1:

4.

4. The time-release, slow-release, sugar-controlled compound grain nutritional powder as described in claim 1, characterized in that, The fast phase layer particles have a particle size of 10-20 mesh, the slow phase layer gel microspheres have a particle size of 20-40 mesh, and the supplementary phase layer particles have a particle size of 20-30 mesh.

5. A method for preparing a time-release, slow-release, sugar-controlled compound cereal nutritional powder according to any one of claims 1-4, characterized in that, Includes the following steps: S1, Prepare the components of each phase: S11. Preparation of the fast-phase particles: Select low-glycemic whole grain raw materials; clean and remove impurities from the low-glycemic whole grain raw materials and pulverize them to 40-60 mesh; add purified water at a solid-liquid ratio of 1:3, adjust the pH to 6.0-6.5, add α-amylase, the amount of enzyme added is 0.1%-0.3% of the mass of the low-glycemic whole grain raw materials, stir and hydrolyze at 50℃ for 10-15 minutes, then raise the temperature to 95℃ and hold for 10 minutes to completely inactivate the α-amylase, pass through a 100-mesh sieve, and spray dry the filtrate at an inlet temperature of 160℃ and an outlet temperature of 80℃ to obtain the fast-phase particles with a particle size controlled at 10-20 mesh, for later use; S12. Preparation of the slow-phase gradient degradation gel microspheres: Gradient microspheres are prepared using an emulsification gelation method: The composite polyphenol-modified resistant starch is dispersed in a 2% (w / w) low-methoxyl pectin solution as the inner phase; β-glucan is prepared into a 2% (w / w) aqueous solution as the outer phase; the inner phase is added dropwise to edible vegetable oil containing food-grade emulsifier under stirring. After pre-forming the inner phase microspheres, the β-glucan solution of the outer phase is gradually added dropwise, while simultaneously adding food-grade calcium chloride solution dropwise to induce gelation. The calcium chloride solution concentration was 0.5 mol / L. The gradual degradation gel microspheres were collected by centrifugation and washed three times with 75% food-grade ethanol and purified water. They were then vacuum dried at 45°C and -0.08 MPa to obtain the gradual degradation gel microspheres with a particle size of 20-40 mesh. The outer β-glucan layer accounted for 40 wt% of the total gel mass, the inner low-methoxyl pectin layer accounted for 40 wt% of the total gel mass, and the intermediate transition layer gradient composite portion accounted for 20 wt% of the total gel mass. These microspheres were then set aside for later use. S13. Preparation of the complementary layer particles: After cleaning and removing impurities from the slow-digesting grains, they are pulverized and passed through an 80-100 mesh sieve. The pulverized grains are added to an aqueous solution of the high molecular weight oat β-glucan at a mass fraction of 5%. After stirring evenly, the complementary layer particles are prepared by spray granulation process. The inlet temperature is 130℃, the outlet temperature is 75℃, and the particle size is controlled at 20-30 mesh. The particles are then set aside for later use. S2. Total mixing: The prepared fast phase layer particles, slow phase layer gradient degradation gel microspheres, and supplementary phase layer particles are dry-mixed evenly according to the ratio, packaged and sterilized to obtain the time-release slow-release sugar-controlled compound grain nutritional powder.

6. The preparation method of a time-release, controlled-sugar compound cereal nutritional powder as described in claim 5, characterized in that, In the preparation process of the gradient degradation gel microspheres in the slow phase layer, the edible vegetable oil is one of soybean oil, rapeseed oil or corn oil, which meets the GB / T national standard for edible oils; after washing with 75% food-grade ethanol, it is washed three times with purified water to completely remove residual ethanol.

7. The preparation method of a time-release, controlled-sugar compound cereal nutritional powder as described in claim 5, characterized in that, In the overall mixing step, a three-dimensional motion mixer is used for dry mixing, with a speed set at 10-20 rpm and a mixing time of 15-25 minutes, to ensure that the fast phase layer particles, the slow phase layer gradient degradation gel microspheres, and the complementary phase layer particles are uniformly dispersed without damaging the particle structure.

8. The preparation method of a time-release, controlled-sugar compound cereal nutritional powder as described in claim 5, characterized in that, In the packaging sterilization step, microwave sterilization or irradiation sterilization is used. The microwave sterilization power is 800W and the time is 3 minutes, or the irradiation sterilization dose is 5-8kGy.

9. The application of the time-release, sugar-controlled compound cereal nutritional powder according to claim 1 in the preparation of instant cereal products.