阅读说明：本技术 一种利用低血糖指数糯米粉制备年糕的方法 (Method for preparing rice cake by using glutinous rice flour with low glycemic index ) 是由 李珍妮 黎宁 黄浩翼 余怡风 施雯怡 夏心蕾 王锐 于 2020-05-26 设计创作，主要内容包括：本发明涉及一种利用低血糖指数糯米粉制备年糕的方法,包含如下步骤：选取糯米为原料,经过浸泡、粉碎、酶解、调质反应、干燥等工艺得到糯米粉,而后以该糯米粉为原料,经预混、蒸制和挤压等工艺得到低血糖指数的年糕。该方法的创新性在于首先通过蛋白酶水解,释放糯米粉原料本身化学组成和结构中具有辅助降低血糖指数功效的成分,而后协同湿热处理调质关键技术,进一步巩固与提高该活性成分协同降低糯米粉血糖指数的能力,赋予制备得到的糯米粉具有较低GI值的属性。以此为原料制备年糕,年糕加工过程进一步降低了产品的血糖指数,从而获得低血糖指数的年糕产品。(The invention relates to a method for preparing rice cakes by using glutinous rice flour with low glycemic index, which comprises the following steps: selecting glutinous rice as a raw material, carrying out processes such as soaking, crushing, enzymolysis, quenching and tempering, drying and the like to obtain glutinous rice powder, and then carrying out processes such as premixing, steaming, extruding and the like to obtain the rice cake with low glycemic index by using the glutinous rice powder as the raw material. The innovativeness of the method is that firstly, components with the effect of assisting in reducing the blood glucose index in the chemical composition and structure of the raw material of the glutinous rice flour are released through protease hydrolysis, and then the key technology of conditioning is coordinated with damp-heat treatment, so that the capability of cooperatively reducing the blood glucose index of the glutinous rice flour by the active components is further strengthened and improved, and the prepared glutinous rice flour has the attribute of lower GI value. The rice cake is prepared by taking the rice cake as a raw material, and the processing process of the rice cake further reduces the glycemic index of the product, so that the rice cake product with low glycemic index is obtained.)

1. A method for preparing rice cake by using glutinous rice flour with low glycemic index is characterized by comprising the following steps:

(1) preparing glutinous rice flour with low glycemic index, wherein the glycemic index of the glutinous rice flour with low glycemic index is 45-65%, the content of peptides with molecular weight less than 5000 Da in the glutinous rice flour accounts for 30-60% of the total protein content, and the content of amino acids L eu, Ile, Phe, Val and Arg in the glutinous rice flour accounts for 30-60% of the total amino acid content;

(2) uniformly mixing glutinous rice flour with low glycemic index, water and salad oil, and steaming on a steamer with big fire until no water is separated out on the surface to obtain an extruded material;

(3) and (4) feeding the extruded material into an extruder, controlling the temperature and the rotating speed, carrying out extrusion forming and cooling to obtain the rice cake with low glycemic index.

2. The method for preparing rice cakes from low-glycemic-index glutinous rice flour according to claim 1, wherein the method for preparing low-glycemic-index glutinous rice flour in the step (1) comprises the steps of:

(1.1) soaking, namely selecting a glutinous rice raw material, cleaning impurities, and then adding water for soaking at the soaking temperature of 25-45 ℃;

(1.2) crushing, namely crushing the soaked sticky rice by a semi-dry method;

(1.3) carrying out specific enzymolysis, adding protease into the crushed glutinous rice flour, uniformly mixing, continuously stirring, and starting enzymolysis after the center of the material reaches the optimal reaction temperature of the protease;

(1.4) carrying out quenching and tempering reaction, taking the glutinous rice flour subjected to enzymolysis, reacting for 0.5-3 h at 90-120 ℃, and drying after the reaction is finished to obtain the glutinous rice flour product with low glycemic index.

3. The method for preparing rice cakes from low-glycemic-index glutinous rice flour according to claim 2, wherein the moisture content of the glutinous rice flour in the pulverization in the step (1.2) is 25% to 45%.

4. The method for preparing rice cakes from low-glycemic-index glutinous rice flour according to claim 2, wherein the average particle size (D50) of the glutinous rice flour after the pulverization in the step (1.2) is 10 to 15 μm.

5. The method for preparing rice cakes from low-glycemic-index glutinous rice flour according to claim 2, wherein the protease type in the step (1.3) is neutral or a combination of neutral and acidic.

6. The method for preparing rice cakes from glutinous rice flour with low glycemic index according to claim 2, wherein the stirring speed of the enzymatic hydrolysis reaction in the step (1.3) is 30-60 rpm.

7. The method for preparing rice cakes from glutinous rice flour with low glycemic index according to claim 1, wherein the mass ratio of the glutinous rice flour with low glycemic index, water and salad oil in the step (2) is (40-55): (40-59): (1-5).

8. The method for preparing rice cakes according to claim 1, wherein the extrusion temperature of the extrusion material in the step (3) is 70-110 ℃ and the extrusion speed is 40-80 rpm when the extrusion material is fed into the extruder.

9. A rice cake made by the method of making a rice cake from low glycemic index glutinous rice flour according to any one of claims 1 to 8 wherein the glycemic index is 40% to 55%.

10. The use of the low-glycemic-index glutinous rice flour according to any one of claims 1 to 6 and the preparation method thereof for preparing foods, medicines and health products.

Technical Field

The invention belongs to the technical field of food biology, and particularly relates to a method for preparing rice cakes by using glutinous rice flour with low glycemic index.

Background

With the improvement of living standard of people, the change of living style and some bad dietary habits of modern people, the dietary structure is continuously changed, the incidence of diseases related to diet, such as hyperglycemia and diabetes, is greatly increased, and the dietary structure poses potential threats to human health. With the age, especially the elderly, the postprandial blood sugar is obviously increased, which is also the main cause of cardiovascular diseases such as coronary heart disease. Glycemic Index (GI) refers to the ability of a sugar-containing product to produce a relative increase in blood glucose levels as compared to the degree of change in blood glucose concentration following ingestion of a reference food (glucose or white bread). And the glycemic response depends largely on the rate of digestion of the food. In recent years, the glycemic index of food has been valued by food companies for its important role in maintaining health and disease control. In future development, low-glycemic-index food is developed and mined as special food for sports, health care and weight reduction, so that enterprises are more competitive and vital.

The main difference between the sticky rice and other rice is that the starch contained in the sticky rice is mainly amylopectin which is 95-100%, and the sticky rice has unique taste, taste and edible value due to the special chemical composition and structure, and is one of the food crops which are loved to eat by people. However, amylopectin is more easily hydrolyzed by amylase than amylose, and the glycemic index is relatively high, and experimental measurements show that: the glycemic index of the glutinous rice flour is usually 85-95%, and the glutinous rice flour belongs to high glycemic index food (GI is more than or equal to 70). The characteristic greatly limits the application range of the glutinous rice flour and increases potential health risks for people who like eating glutinous rice products.

The processing industry of glutinous rice flour in China is not developed, the glutinous rice flour is mostly in a small workshop type, and only the glutinous rice flour is primarily processed. The process is advanced, only a few enterprises with guaranteed quality exist, and the current research mainly focuses on the aspects of crushing technology, machinery, industry and the like so as to promote the development of processing of the glutinous rice flour from workshop-type production to industrial and large-scale production. The research report is not seen for a while in the aspect of reducing the blood glucose index of the glutinous rice flour based on the structural characteristics of the glutinous rice flour.

The research shows that the vegetable protein has the functions of promoting insulin activity and inhibiting target metabolic enzyme activity, and the activity is closely related to the amino acid content in the protein, particularly the contents of L eu, Ile, Phe, Val, Arg and the like.

Disclosure of Invention

On the basis of the previous research, the invention creatively screens specific protease from the chemical composition and structural characteristics of the glutinous rice flour raw material, releases potential protein peptide, amino acid and other components with the effect of assisting in reducing the blood glucose index in the glutinous rice flour raw material through hydrolysis reaction, and coordinates with a key technology of moist heat treatment and tempering, promotes the interaction between the functional protein peptide and amino acid components released by protease hydrolysis and the glutinous rice starch, further consolidates and improves the capability of the active components for coordinating and reducing the blood glucose index of the glutinous rice flour, and endows the prepared glutinous rice flour with the attribute of lower blood glucose index. The rice cake prepared by using the raw materials is subjected to premixing, steaming and extrusion processes, so that the blood glucose index is further reduced, and a rice cake product with low blood glucose index is obtained.

The invention provides a method for preparing rice cakes by using glutinous rice flour with low glycemic index, which comprises the following steps:

(1) selecting a glutinous rice raw material, cleaning impurities, and then adding water for soaking at the temperature of 25-45 ℃ until the water absorption rate of rice grains approaches to balance.

(2) And (3) taking the soaked glutinous rice, and crushing by a semidry method, wherein the water content of the glutinous rice flour is 25-45% during crushing, and the average particle size (D50) of the crushed rice milk is 10-15 microns.

(3) Adding neutral or neutral and acidic protease into the pulverized glutinous rice flour, and starting enzymolysis after the materials are uniformly mixed and the center of the materials reaches the optimal reaction temperature of the protease. And carrying out enzymolysis by adopting a semidry method, and controlling the stirring speed of the enzymolysis reaction to be 30-60 rpm so as to fully mix and react.

(4) Taking glutinous rice flour subjected to enzymolysis reaction, carrying out mass reaction for 0.5-3 h under the condition of 90-120 ℃, and drying after the reaction to obtain a glutinous rice flour product with low glycemic index, wherein the glutinous rice flour prepared by the process steps contains 30-60% of peptide with the molecular weight of less than 5000 Da, and contains 30-60% of L eu, Ile, Phe, Val and Arg, and the in vitro digestibility of starch in the glutinous rice flour is 45-65% of the GI value of the glycemic index.

(5) The glutinous rice flour with the low glycemic index is used as a raw material, and is mixed with water and salad oil according to the mass ratio of (40-55): (40-59): (1-5) uniformly mixing, and steaming on a steamer with strong fire until no water is separated out on the surface to obtain an extruded material; and then, feeding the extruded material into an extruder, controlling the extrusion temperature to be 70-110 ℃ and the extrusion rotation speed to be 40-80 rpm, and carrying out extrusion forming and cooling on the material in an extrusion cavity to obtain the rice cake with low glycemic index, wherein the measured glycemic index of the rice cake is 40-55%.

The invention has the advantages of

(1) And (5) cleaning production. After the glutinous rice flour is processed by the soaking process, no additional water is added in the steps of crushing, specific enzymolysis and quenching and tempering reaction, no processing wastewater is discharged in the production process, and the integral moisture of the glutinous rice flour is kept at 25-45%. In the conventional water-milled glutinous rice flour production process, water with the mass about 3 times that of the glutinous rice is required for production and processing in the crushing process, and meanwhile, after solid-liquid separation and before the drying process, the water with the mass about 3 times that of the glutinous rice is discharged as waste water. In contrast, the combined process flow adopted by the invention meets the requirement of clean production.

(2) The processing idea is novel. According to the specific enzymolysis process of the glutinous rice flour, a semi-dry enzymolysis idea is adopted, the protease and the glutinous rice flour under the condition are subjected to local micro-reaction, and finally, components with the effect of assisting in reducing the GI value, such as protein peptide, amino acid and the like generated by enzymolysis are retained in the glutinous rice flour, are tightly combined with the chemical composition of the glutinous rice flour and are not relatively separated; the subsequent tempering reaction process further consolidates and improves the interaction between the active ingredients and the chemical ingredients of the glutinous rice flour, and the GI value of the glutinous rice flour is synergistically reduced.

(3) The product quality is good. According to the invention, aiming at the characteristic of high GI value caused by the chemical composition and structure of the glutinous rice flour, specific protease is screened, potential protein peptide, amino acid and other components with the effect of assisting in reducing the GI value in the raw material of the glutinous rice flour are released by hydrolysis reaction, and the GI value of the prepared glutinous rice flour is lower than that of the traditional glutinous rice flour by coordinating with a key technology of conditioning by wet heat treatment, and the glutinous rice flour can be widely applied to various aspects of food, medicines and health care products. Meanwhile, the rice cake prepared by using the rice cake as the raw material has a further reduced glycemic index, so that a rice cake product with a low glycemic index is obtained.

Drawings

FIG. 1: the glutinous rice flour sample prepared by the invention has an X-diffraction pattern;

FIG. 2: crystallinity and GI value of the glutinous rice flour;

FIG. 3: GI value of rice cake prepared from glutinous rice flour;

FIG. 4: comparing the discharge amount of the production water and the discharge amount of the waste water.

Detailed Description