Method for preparing debranched grain powder-monoglyceride compound by utilizing enzymolysis and extrusion treatment

Abstract

The invention discloses a method for preparing a debranched grain powder-monoglyceride compound by utilizing enzymolysis and extrusion treatment, and belongs to the technical field of functional foods. The method comprises the following steps: fully mixing a cereal powder raw material with debranching enzyme, carrying out primary extrusion debranching by using a twin-screw extruder, collecting the debranching cereal powder, drying and crushing; and fully mixing the obtained debranched grain powder with monoglyceride, carrying out secondary extrusion by using a twin-screw extruder, and realizing the formation of the debranched grain powder-monoglyceride compound in the secondary extrusion. According to the method, high-efficiency preparation of the debranched grain powder-monoglyceride compound at a high grain powder concentration in a short time is realized, and the problems of complex preparation process, low raw material concentration, long preparation time and low compounding efficiency of the starch-lipid compound are solved; the content of the RS5 type resistant starch is increased, and a theoretical basis and actual guidance are provided for continuous industrial production of the resistant starch.

Description

Technical Field

[0001] The invention belongs to the technical field of functional foods, and in particular relates to a method for preparing a debranched cereal flour-monoglyceride complex by using enzymatic hydrolysis and co-extrusion treatment. Background Art

[0002] Starch is the main source of carbohydrates and energy in the human diet, accounting for 40%-80% of energy intake, and plays a vital role in human health. Different starch compositions (rapidly digested starch RDS, slowly digested starch SDS and resistant starch RS) lead to uneven starch digestion, causing instability in the body's postprandial blood sugar levels, insulin and cholesterol balance, and then causing the occurrence of some chronic diseases such as obesity and diabetes. Resistant starch cannot be digested in the small intestine, but is fermented and degraded by intestinal flora in the colon to produce short-chain fatty acids and gas. Resistant starch plays a key role in promoting a variety of beneficial health effects, including lowering blood sugar and cholesterol, inhibiting body fat accumulation, increasing mineral absorption, reducing digestive tract cancer and preventing gallstone formation.

[0003] RS5 is an important type of resistant starch. Its formation process is as follows: when the system contains suitable ligands, it will induce amylose to form a helical structure with a hydrophobic cavity. This cavity provides a highly affinity binding site for non-polar lipid ligands, allowing the lipid hydrophobic tail to enter the helical cavity of amylose, forming a V-shaped structure that is resistant to amylase hydrolysis. Among them, lipids mainly form complexes with amylose, and amylopectin is difficult to form complexes with lipids because of its short branches that hinder the formation of a helical conformation. Therefore, the amylose content in starch has an important influence on the formation of starch-lipid complexes.

[0004] At present, the preparation of RS5 mainly uses starch as raw material, which is compounded with lipids to form a V-type complex with a single helical structure. There are still many problems in the existing preparation methods of RS5 resistant starch. On the one hand, it takes a lot of resources to extract starch from grains. On the other hand, the preparation generally faces the problems of low yield and high energy consumption. The main reasons include two aspects: first, the high viscosity of starch after gelatinization causes the concentration of the reaction substrate starch to be low; second, the content of amylose in natural starch is relatively low, and the low amylose content also limits the yield of RS5 resistant starch to a certain extent. Directly using grain flour as raw material to prepare resistant starch can solve the problem of high energy consumption. Grain flour contains nutrients such as dietary fiber, polyphenols and vitamins, and has antioxidant and immune-enhancing functions. However, the starch structure in native grain flour is easily digested and absorbed by the human body, which makes it lack advantages in digestibility. Therefore, how to use grain flour to prepare RS5 resistant starch with good digestibility and high yield has become a difficulty in current research.

[0005] The use of screw extrusion technology to prepare starch-lipid complexes, namely RS5 resistant starch, helps to improve the problems of low substrate starch concentration and low amylose content. For example, patent CN113907332A discloses an efficient preparation method for a starch-lipid complex with controllable crystal form, and uses an extrusion cooking method to efficiently produce a starch-lipid complex with controllable crystal form. This method uses extrusion technology to greatly increase the content of substrate starch, but the content of starch (amylose) that effectively reacts is low, so the yield of its complex is still low. Patent CN111675830A discloses a method for preparing a debranched starch-lipid complex, using starch as a raw material, and using a debranching enzyme to debranch starch to obtain debranched starch, so as to increase the amylose content, thereby increasing the complexing ability of starch, and then using lipids as ligands to prepare debranched starch-lipid complexes in an aqueous phase system. However, the substrate concentration of this method is generally low, time-consuming, and the process flow is complicated. Patent CN117837762A discloses a method for preparing debranched starch-lipid complexes using a two-step extrusion method, in which starch is pre-gelatinized by one-step extrusion, and pullulanase and lauric acid are added during the second extrusion for simultaneous debranching and compounding, which greatly increases the content of resistant starch. However, for cereal flour, this method will compound with endogenous lipids during pre-gelatinization, which greatly reduces the gelatinization effect and affects the debranching effect during the second extrusion. At the same time, the pullulanase hydrolysis temperature needs to be maintained at around 60°C. At this relatively low temperature, the compounding efficiency of the debranched straight-chain starch and lipids is low, and is not as good as the compounding effect at high temperature. In summary, inventing new strategies to improve the preparation efficiency of cereal flour-lipid complexes is of great significance for the industrial production of RS5-type resistant starch. Summary of the invention

[0006] In view of the above problems, the purpose of the present invention is to prepare digestion-resistant food ingredients using cereal flour as raw material, and proposes to use a step-by-step extrusion method (extrusion debranching-extrusion compounding method) to achieve efficient and continuous industrial production of debranched cereal flour-monoglyceride complexes. Extrusion is an industrialized continuous thermomechanical production technology with controllable temperature, strong shear, short time and low cost, and has the advantages of versatility and high yield. In the present invention, a debranching enzyme is added during the first extrusion to achieve effective debranching of cereal flour, and then the debranched cereal flour is mixed with monoglyceride for a second extrusion, and a debranched cereal flour-monoglyceride complex is obtained in the second extrusion. Debranching and compounding are divided into two steps, which significantly improves the digestion resistance of cereal flour and realizes the extrusion preparation of debranched cereal flour-monoglyceride complexes.

[0007] In view of the above purpose, the present invention first provides a method for preparing a debranched cereal flour-monoglyceride complex by enzymatic co-extrusion treatment, the method comprising the following steps:

[0008] (1) fully mixing the cereal powder and the debranching enzyme, and adding the mixture to the feeding end of a twin-screw extruder. After extrusion, collecting the debranched cereal powder, drying, crushing and sieving to obtain the debranched cereal powder;

[0009] (2) Mixing the debranched cereal powder obtained in step (1) with monoglyceride, adding the mixture to the feeding end of a twin-screw extruder, collecting the extruded debranched cereal powder-monoglyceride complex after extrusion, drying the mixture, and then crushing the mixture.

[0010] In one embodiment of the present invention, the cereal flour includes at least one of rice flour, wheat flour, soybean flour, corn flour, sorghum flour and highland barley flour.

[0011] In one embodiment of the present invention, the debranching enzyme in step (1) comprises at least one of pullulanase, isoamylase, oligoglucosidase and amylo-1,6-glucosidase.

[0012] In one embodiment of the present invention, the added amount of the debranching enzyme is 60-100 U / g (w / w, based on dry basis of cereal powder), and the enzyme activity of the debranching enzyme is 1000-2000 U / g.

[0013] In one embodiment of the present invention, in step (1), the moisture content of the material during extrusion is 50-60%.

[0014] In one embodiment of the present invention, in step (1), the rotation speed of the twin-screw extruder is 100-250 rpm; the temperatures of the 6 temperature zones of the extruder are 60-70°C in zone 1, 60-70°C in zone 2, 60-70°C in zone 3, 60-70°C in zone 4, 60-70°C in zone 5, and 90-110°C in zone 6.

[0015] In one embodiment of the present invention, the drying temperature in step (1) is 45-50° C., the drying time is 24-36 hours, and the powder is sieved through a 60-mesh sieve.

[0016] In one embodiment of the present invention, the monoglyceride described in step (2) includes at least one of glyceryl monolaurate, glyceryl monopalmitate, glyceryl monostearate, glyceryl monooleate, glyceryl monolinoleate, glyceryl monobehenate, and glyceryl monolinolenate, preferably glyceryl monostearate.

[0017] In one embodiment of the present invention, the amount of monoglyceride added in step (2) is 2-8% of the mass of the debranched cereal flour.

[0018] In one embodiment of the present invention, in step (2), the moisture content of the material during extrusion is 40-50%.

[0019] In one embodiment of the present invention, in step (2), the rotation speed of the twin-screw extruder is 100-250 rpm; the temperatures of the 6 temperature zones of the extruder are: zone 1 temperature 40-50°C, zone 2 temperature 60-70°C, zone 3 temperature 80-90°C, zone 4 temperature 80-90°C, zone 5 temperature 100-110°C, zone 6 temperature 110-120°C.

[0020] In one embodiment of the present invention, the drying temperature in step (2) is 45-50° C., the drying time is 24-36 hours, and the powder is sieved through a 60-mesh sieve.

[0021] The second object of the present invention is to provide a debranched cereal flour-monoglyceride complex prepared according to the above method.

[0022] The third object of the present invention is to provide an application of the debranched cereal flour-monoglyceride complex in the field of food preparation.

[0023] In one embodiment of the present invention, the application includes using the debranched cereal flour-monoglyceride complex to prepare food and medicine that assist in improving hyperglycemia and intestinal health, and preventing diabetes and colon cancer.

[0024] Beneficial effects:

[0025] (1) The present invention uses cereal flour as raw material and adopts a two-step extrusion method to prepare a debranched cereal flour-monoglyceride complex. By using extrusion technology and debranching enzyme, a high-content debranched cereal flour-monoglyceride complex is obtained through two extrusions, which significantly reduces the digestibility of starch in the cereal flour.

[0026] (2) After the first extrusion with the addition of debranching enzyme, the cereal flour can be fully debranched, and the amylose content in the cereal flour increases. During the second extrusion, the debranched cereal flour immediately forms a debranched cereal flour-monoglyceride complex with the dissolved monoglyceride. The method is simple and efficient, and can efficiently complete the formation of a debranched cereal flour-monoglyceride complex with high thermal stability at a high starch concentration and in a short time, overcoming the problems of complex preparation process, low starch concentration, long reaction time, and low complexation efficiency in the prior art, and can achieve continuous production.

[0027] (3) The yield of the debranched cereal flour-monoglyceride complex prepared by the present invention is high, and with the increase of the amount of lipid added, the content of resistant starch in the complex can be as high as 43.27%, which is much higher than the content of resistant starch in ordinary cereal flour and cereal flour after extrusion.

[0028] (4) The present invention will provide a theoretical basis and practical guidance for the continuous industrial production of debranched cereal flour-monoglyceride complexes, and provide feasible strategies and methods for the industrial production of resistant starch and the development of low glycemic index foods. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The XRD patterns of indica rice flour, the debranched indica rice flour-monoglyceride complex prepared in Examples 1 to 4, the extruded indica rice flour and the extruded indica rice flour-monoglyceride complex prepared in Comparative Examples 1 to 5 are shown. DETAILED DESCRIPTION

[0030] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] The twin-screw extruder used in the present invention is from Shandong Zhennuo Intelligent Equipment (Shandong) Co., Ltd., model AHT36-28D, and the extruder has a total of 6 heating temperature zones.

[0032] The enzyme preparation used in the examples of the present invention is pullulanase (enzyme activity is 1000 U / g), which was purchased from Suzhou Great Pharmaceutical Technology Co., Ltd.

[0033] The cereal flour used in the embodiment of the present invention is indica rice flour, which was purchased from Anhui Fengshuo Agricultural Technology Co., Ltd.

[0034] The monoglyceride used in the embodiment of the present invention is glyceryl monostearate, which was purchased from Linyi Lusen Chemical Co., Ltd.

[0035] Example 1

[0036] A method for preparing a debranched cereal flour-monoglyceride complex by enzymatic co-extrusion treatment, the method specifically comprising the following steps:

[0037] (1) Indica rice flour and pullulanase (60 U / g, w / w, based on the dry basis of indica rice flour) are fully mixed, added to the feeding end of a twin-screw extruder, the moisture content of the material is set to 60 wt %, the screw speed is 150 rpm, the temperatures of zones I, II, III, IV, V, and VI of the extruder (AHT36-28D) are set to 60, 65, 65, 65, 65, and 95° C., respectively, and extrusion is started, the debranched indica rice flour is collected, dried at 45° C. for 24 h, crushed, and passed through a 60-mesh sieve to obtain debranched indica rice flour;

[0038] (2) mixing the debranched indica rice flour extruded in step (1) with 2% of glyceryl monostearate (based on the dry mass of the debranched indica rice flour), adding the mixture to a feeding end of a twin-screw extruder, and setting the moisture content of the mixture to 40 wt %; setting the temperatures of zones I, II, III, IV, V, and VI of the extruder to 40, 60, 80, 80, 100, and 120° C., respectively, and the screw speed to 150 rpm, and starting extrusion; collecting the extruded debranched indica rice flour-monostearate complex, drying it at 45° C. for 24 h, and then crushing it and passing it through a 60-mesh sieve.

[0039] Example 2

[0040] A method for preparing a debranched cereal flour-monoglyceride complex by enzymatic co-extrusion treatment, the method specifically comprising the following steps:

[0041] (1) Indica rice flour and pullulanase (60 U / g, w / w, based on the dry basis of indica rice flour) are fully mixed, added to the feeding end of a twin-screw extruder, the moisture content of the material is set to 60 wt %, the screw speed is 150 rpm, the temperatures of zones I, II, III, IV, V, and VI of the extruder (AHT36-28D) are set to 60, 65, 65, 65, 65, and 95° C., respectively, and extrusion is started, the debranched indica rice flour is collected, dried at 45° C. for 24 h, crushed, and passed through a 60-mesh sieve to obtain debranched indica rice flour;

[0042] (2) mixing the debranched indica rice flour extruded in step (1) with 4% monostearate glyceryl (based on the dry matter weight of the debranched indica rice flour), and adding the mixture to the feeding end of a twin-screw extruder, wherein the moisture content of the feed is set to 40 wt %; setting the temperatures of zones I, II, III, IV, V, and VI of the extruder to 40, 60, 80, 80, 100, and 120° C., respectively, and the screw speed to 150 rpm, and starting extrusion; collecting the extruded debranched indica rice flour-monostearate complex, drying it at 45° C. for 24 h, and then crushing it and passing it through a 60-mesh sieve.

[0043] Example 3

[0044] A method for preparing a debranched cereal flour-monoglyceride complex by enzymatic co-extrusion treatment, the method specifically comprising the following steps:

[0045] (1) Indica rice flour and pullulanase (60 U / g, w / w, based on the dry basis of indica rice flour) are fully mixed, added to the feeding end of a twin-screw extruder, the moisture content of the material is set to 60 wt %, the screw speed is 150 rpm, the temperatures of zones I, II, III, IV, V, and VI of the extruder (AHT36-28D) are set to 60, 65, 65, 65, 65, and 95° C., respectively, and extrusion is started, the debranched indica rice flour is collected, dried at 45° C. for 24 h, crushed, and passed through a 60-mesh sieve to obtain debranched indica rice flour;

[0046] (2) mixing the debranched indica rice flour extruded in step (1) with 6% of glyceryl monostearate (based on the dry weight of the debranched indica rice flour), and adding the mixture to a feeding end of a twin-screw extruder, wherein the moisture content of the feed is set to 40 wt %; setting the temperatures of zones I, II, III, IV, V, and VI of the extruder to 40, 60, 80, 80, 100, and 120° C., respectively, and the screw speed to 150 rpm, and starting extrusion; collecting the extruded debranched indica rice flour-monostearate complex, drying it at 45° C. for 24 h, and then crushing it and passing it through a 60-mesh sieve.

[0047] Example 4

[0048] A method for preparing a debranched cereal flour-monoglyceride complex by enzymatic co-extrusion treatment, the method specifically comprising the following steps:

[0049] (1) Indica rice flour and pullulanase (60 U / g, w / w, based on the dry basis of indica rice flour) are fully mixed, added to the feeding end of a twin-screw extruder, the moisture content of the material is set to 60 wt %, the screw speed is 150 rpm, the temperatures of zones I, II, III, IV, V, and VI of the extruder (AHT36-28D) are set to 60, 65, 65, 65, 65, and 95° C., respectively, and extrusion is started, the debranched indica rice flour is collected, dried at 45° C. for 24 h, crushed, and passed through a 60-mesh sieve to obtain debranched indica rice flour;

[0050] (2) mixing the debranched indica rice flour extruded in step (1) with 8% of glyceryl monostearate (based on the dry matter weight of the debranched indica rice flour), and adding the mixture to a feeding end of a twin-screw extruder, wherein the moisture content of the feed is set to 40 wt %; setting the temperatures of zones I, II, III, IV, V, and VI of the extruder to 40, 60, 80, 80, 100, and 120° C., respectively, and the screw speed to 150 rpm, and starting extrusion; collecting the extruded debranched indica rice flour-monostearate complex, drying it at 45° C. for 24 h, and then crushing it and passing it through a 60-mesh sieve.

[0051] Comparative Example 1

[0052] Add indica rice flour to the feeding end of a twin-screw extruder, set the moisture content to 40 wt %, the screw speed to 150 rpm, set the temperatures of zones Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ, and VI of the extruder (AHT36-28D) to 40, 60, 80, 80, 100, and 120 ° C, respectively, and start extrusion. Collect the fully gelatinized indica rice flour, dry it at 45 ° C for 24 h, then grind it and pass it through a 60-mesh sieve.

[0053] Comparative Example 2

[0054] The indica rice flour was fully mixed with 2% monolaurin (based on the dry mass of the indica rice flour), added to the feeding end of the twin-screw extruder, the moisture content was set to 40wt%, the screw speed was set to 150rpm, the temperatures of the extruder (AHT36-28D) zones Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ, and VI were set to 40, 60, 80, 80, 100, and 120°C, respectively, and extrusion was started. The extrudate was collected and dried at 45°C for 24 hours, then crushed and passed through a 60-mesh sieve.

[0055] Comparative Example 3

[0056] Indica rice flour and 2% monopalmitin glyceride (based on the dry mass of indica rice flour) were fully mixed and added to the feeding end of a twin-screw extruder. The moisture content was set to 40wt%, the screw speed was set to 150rpm, and the temperatures of zones Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ, and VI of the extruder (AHT36-28D) were set to 40, 60, 80, 80, 100, and 120°C, respectively. Extrusion was started, and the extrudates were collected, dried at 45°C for 24 hours, crushed, and passed through a 60-mesh sieve.

[0057] Comparative Example 4

[0058] The indica rice flour was fully mixed with 2% monostearate glyceryl (based on the dry mass of the indica rice flour), added to the feeding end of the twin-screw extruder, the moisture content was set to 40wt%, the screw speed was set to 150rpm, the temperatures of the extruder (AHT36-28D) zones Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ, and VI were set to 40, 60, 80, 80, 100, and 120°C, respectively, and extrusion was started. The extrudate was collected and dried at 45°C for 24 hours, then crushed and passed through a 60-mesh sieve.

[0059] Comparative Example 5

[0060] The indica rice flour was fully mixed with 2% monoolein (based on the dry mass of the indica rice flour), added to the feeding end of the twin-screw extruder, the moisture content was set to 40wt%, the screw speed was set to 150rpm, the temperatures of the extruder (AHT36-28D) zones Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ, and VI were set to 40, 60, 80, 80, 100, and 120°C, respectively, and extrusion was started. The extrudate was collected and dried at 45°C for 24 hours, then crushed and passed through a 60-mesh sieve.

[0061] Table 1 Contents of fast digestible starch, slow digestible starch and resistant starch in samples

[0062]

[0063]

[0064] (Note: Different letters abc indicate that there are significant differences between the data groups, with p less than 0.05)

[0065] like Figure 1As shown in Table 1, after extrusion, the ordered structure of starch in indica rice flour is destroyed, and the relative crystallinity is greatly reduced. Adding 2% monostearate glyceryl during extrusion can effectively improve the ordered structure of starch. However, the content of amylose in indica rice flour is limited, and when compounded with monostearate glyceryl, the effect of improving the relative crystallinity is limited. After extrusion with pullulanase once, the content of amylose is significantly increased, forming a more ordered crystalline structure, and the relative crystallinity is greatly improved. After extrusion with pullulanase once, the content of amylose in the example sample is determined to be 49.63% using the Megazyme amylose and amylopectin assay kit. Compared with indica rice flour, the amylose content of debranched indica rice flour is increased by 122.76%. When the monostearate content is 4%, the relative crystallinity of the composite is 36.76%. As the monostearate content increases to 8%, the lipid content in the complex is too high, and the excess lipid will undergo a self-aggregation effect, thereby reducing the lipid content complexed with the starch in indica rice flour, and further causing the relative crystallinity of the complex to decrease instead of increase.

[0066] The content of resistant starch in each embodiment and comparative example sample was measured using the Englyst in vitro simulated digestion method, and the results are shown in Table 1. It can be seen from Table 1 that when the content of monostearate glycerol is 4%, the content of resistant starch in the composite is 43.27%. As the content of monostearate glycerol increases to 8%, the lipid content in the composite is too much, and the excess lipid will undergo a self-aggregation effect, thereby causing the lipid content compounded with starch in indica rice flour to decrease, thereby causing the RS content to decrease instead of increase, which is consistent with the XRD results. It can be seen from Table 1 that after extrusion debranching once and then compounding with monoglyceride, its resistant starch content is much higher than the content of resistant starch in indica rice flour and indica rice flour-monoglyceride composite formed by extrusion without debranching.

[0067] Liu et al. reported that 40% corn starch was extruded and pregelatinized, and then the pregelatinized corn starch was compounded with 8% lauric acid to prepare a debranched starch-lauric acid complex with a resistant starch content of 39.34% (Q. Liu, HA Guan, YX Guo, DX Wang, YY Yang, HY Ji, et al. Structure and in vitro digestibility of amylose-lipid complexes formed by an extrusion-debranching-complexing strategy [J]. Food Chemistry, 2024, 437: 137950). In the present invention, the resistant starch content of the debranched cereal flour-monoglyceride complex (monostearin content of 4%) obtained by enzymatic co-extrusion treatment is 43.27%, which is much higher than the result of the debranched starch-lipid complex obtained by two-step extrusion method in the prior art. In addition, it was found during the experiment that when indica rice flour was used as raw material and the two-step extrusion method in the prior art (the method in Q. Liu, HA Guan, YX Guo, DX Wang, YY Yang, HY Ji, et al. Structure and in vitro digestibility of amylose–lipid complexes formed by an extrusion-debranching-complexing strategy [J]. Food Chemistry, 2024, 437: 137950) was used to prepare debranched indica rice flour-monoglyceride complexes, during the first step of extrusion gelatinization, the starch in the cereal flour would be compounded with endogenous lipids, affecting the debranching effect during the second extrusion, resulting in the content of resistant starch in the finally prepared debranched indica rice flour-monoglyceride complex being much lower than that in the embodiment of the present invention.

[0068] The preparation method of the debranched cereal powder-monoglyceride complex of the present invention realizes the increase of the straight-chain starch content and the formation of the debranched cereal powder-monoglyceride complex at a high cereal powder substrate concentration and in a short time by two extrusions, and the resistant starch content can reach 43.27%, providing a new raw material (cereal powder) and a feasible method for the industrial production of RS5 resistant starch. The method is simple to operate and has high production efficiency, and can be applied to the continuous industrial production of RS5 resistant starch.

[0069] In addition, comparative examples 2 to 5 of the present invention compare the resistant starch content in the composites of different monoglycerides and indica rice flour. From the data in Table 1, it can be seen that the use of glyceryl monostearate has the best effect. Although the resistant starch content in the composite formed by the combination of glyceryl monolaurate and indica rice flour is slightly lower, it is close to the resistant starch content in the monostearate-indica rice flour composite, indicating that the use of glyceryl monolaurate can also increase the resistant starch content.

[0070] The embodiments provided above are not intended to limit the scope of the present invention, and the steps described are not intended to limit the execution order thereof. Those skilled in the art may make obvious improvements to the present invention in combination with existing common knowledge, which also fall within the scope of protection defined by the claims of the present invention.

Claims

1. A method for preparing a debranched cereal flour-monoglyceride complex by enzymatic co-extrusion treatment, characterized in that: The method comprises the following steps: (1) fully mixing the cereal powder and the debranching enzyme, and adding the mixture to the feeding end of a twin-screw extruder. After extrusion, collecting the debranched cereal powder, drying, crushing and sieving to obtain the debranched cereal powder; (2) Mixing the debranched cereal powder obtained in step (1) with monoglyceride, adding the mixture to the feeding end of a twin-screw extruder, collecting the extruded debranched cereal powder-monoglyceride complex after extrusion, drying the mixture, and then crushing the mixture.

2. The method according to claim 1, characterized in that: The cereal flour comprises at least one of rice flour, wheat flour, soybean flour, corn flour, sorghum flour and highland barley flour, and the debranching enzyme in step (1) comprises at least one of pullulanase, isoamylase, oligoglucosidase and amylo-1,6-glucosidase.

3. The method according to claim 1, characterized in that Calculated on a dry basis of cereal flour, the added amount of the debranching enzyme is 60-100 U / g, and the enzyme activity of the debranching enzyme is 1000-2000 U / g.

4. The method according to claim 1, characterized in that In step (1), the moisture content of the material during extrusion is 50-60%, the rotation speed of the twin-screw extruder is 100-250rpm; the temperatures of the six temperature zones of the extruder are respectively 60-70°C in zone one, 60-70°C in zone two, 60-70°C in zone three, 60-70°C in zone four, 60-70°C in zone five, and 90-110°C in zone six; the drying temperature is 45-50°C, the drying time is 24-36h, and the material is sieved through a 60-mesh sieve after crushing.

5. The method according to claim 1, characterized in that The monoglyceride described in step (2) includes at least one of glyceryl monolaurate, glyceryl monopalmitate, glyceryl monostearate, glyceryl monooleate, glyceryl monolinoleate, glyceryl monobehenate, and glyceryl monolinolenate, preferably glyceryl monostearate.

6. The method according to claim 1, characterized in that The amount of monoglyceride added in step (2) is 2-8% of the mass of the debranched cereal flour.

7. The method according to claim 1, characterized in that In step (2), the moisture content of the material during extrusion is 40-50%, the rotation speed of the twin-screw extruder is 100-250rpm; the temperatures of the six temperature zones of the extruder are respectively: zone one temperature 40-50°C, zone two temperature 60-70°C, zone three temperature 80-90°C, zone four temperature 80-90°C, zone five temperature 100-110°C, zone six temperature 110-120°C, the drying temperature is 45-50°C, the drying time is 24-36h, and the material is sieved through a 60-mesh sieve after crushing.

8. The debranched cereal flour-monoglyceride complex prepared according to the method according to any one of claims 1 to 7.

9. Use of the debranched cereal flour-monoglyceride complex according to claim 8 in the field of food preparation.

10. The use according to claim 9, characterized in that: The application includes using the debranched cereal flour-monoglyceride complex to prepare food that helps improve hyperglycemia and intestinal health and prevents diabetes and colon cancer.

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