Method for predicting content of resistant starch
Through hydrolysis and enzymatic reaction combined with glucose assay, the problem of difficult to accurately and quickly determine the resistant starch content in rice is solved, and efficient and low-cost resistant starch content is achieved.
Patent Information
- Application Number
- CN202510469854.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-15
- Publication Date
- 2025-07-11
AI Technical Summary
The prior art is difficult to accurately and quickly determine the resistant starch content in rice, and the standard method is high and the time is long.
The glucose content in the hydrolysis product was determined by hydrolysis and enzymatic reaction combined with glucose assay, and the content of fast-moving starch, slow-moving starch and resistant starch were calculated, using cheap reagents and simplified steps.
The accurate determination of the resistant starch content was achieved, the correlation coefficient reached 0.99, the cost was reduced to one-tenth of the standard method, and the time was shortened to one-quarter of the standard method.
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Abstract
Description
Technical Field
[0001] The present disclosure relates to the biological field, and in particular to a method for predicting the content of resistant starch. Background Art
[0002] Clinical studies have shown that low GI (glycemic index) rice is a type of rice with a glycemic index of less than or equal to 55. Long-term consumption of low GI rice can help patients effectively control their blood sugar levels and weight. Low GI rice is rich in resistant starch, with a GI value of ≤55; while ordinary rice basically does not contain resistant starch, with a GI value of >83, and is a high GI food. Resistant starch is a general term for starch or starchy foods that cannot be degraded and absorbed by the human small intestine but can be fermented and utilized in the colon, and therefore has the function of lowering postprandial blood sugar and insulin response. Another definition of resistant starch is to divide it into three categories based on the length of time it takes for starch to be digested by the human body: fast-digesting starch (can be digested and absorbed within 20 minutes in the small intestine), slow-digesting starch (can be digested and absorbed in 20 to 120 minutes in the small intestine), and resistant starch (cannot be digested and absorbed after 120 minutes in the small intestine). Therefore, based on these two definitions, the absolute and relative values of resistant starch content can be calculated respectively.
[0003] At present, the rapid prediction method is often used to detect the resistant starch content in rice. This method uses the correlation between the resistant starch content and the cooking characteristics of rice to predict the resistant starch content. Specifically, when detecting the resistant starch of japonica rice, the weight of the polished rice sample to be tested and the weight of the polished rice sample after cooking are measured in turn, and the resistant starch content of japonica rice is predicted based on the water absorption rate of the polished rice sample; when detecting the resistant starch of indica rice, the weight of the polished rice sample to be tested, the weight of the polished rice sample after cooking, and the weight of the polished rice sample after cooking are measured in turn, and the resistant starch content of indica rice is predicted based on the cooking water absorption rate and cooking and recovery water loss rate of the polished rice sample. The rapid prediction method can only preliminarily determine the range of the resistant starch content of the sample to be tested, and cannot obtain an accurate value with a correlation coefficient of about 0.99, which brings inconvenience to predicting the GI of rice. If the industry standard method is used to determine resistant starch, an imported test kit must be used. The high cost of the test kit will increase the testing cost and the testing time is long, which also brings inconvenience to the determination of resistant starch.
[0004] Public Content
[0005] In order to solve the problems of the prior art, the present disclosure provides a method for predicting the content of resistant starch. The technical solution is as follows:
[0006] The present disclosure provides a method for predicting resistant starch content, the method comprising:
[0007] The powdered sample to be tested is hydrolyzed in a water bath to obtain a hydrolyzate;
[0008] Add an enzymatic hydrolysate to the hydrolysis product to carry out a digestion reaction to obtain a reaction solution;
[0009] At 0 minute, 20 minutes, and 240 minutes of digestion respectively, take out the reaction solution and add it to an anhydrous ethanol solution to terminate the digestion reaction;
[0010] Determine the glucose content in the taken-out reaction solution;
[0011] Take a glucose standard, the taken-out reaction solution, and sodium acetate as a blank control, add a glucose determination reagent to each, then perform a water bath, and measure the absorbance.
[0012] The hydrolyzed starch content at time t In the formula, Abst is the absorbance.
[0013] The hydrolyzed starch content S(t) at time t = G(t) × 0.9 mg.
[0014] The content of rapidly digestible starch In the formula, W is the total mass of the rice flour.
[0015] The content of slowly digestible starch
[0016] The content of resistant starch RS% = (1 - RDS% - SDS%) × 100%.
[0017] Specifically, the volume ratio of the reaction solution to the anhydrous ethanol solution is 1:9.
[0018] Specifically, the preparation method of the sodium acetate buffer solution includes: taking 90.58 g of sodium acetate trihydrate, adding 300 μL of double-distilled water to dissolve it, adjusting the pH value to 6.0 with glacial acetic acid, and then adding double-distilled water to make the volume up to 500 mL.
[0019] Specifically, when the test sample is rice, mill the rice to obtain rice flour, pass the rice flour through a 100-mesh sieve, and dry the sieved rice flour to obtain the powdery test sample.
[0020] Specifically, the drying temperature is 42 °C.
[0021] Specifically, weigh 0.1 g of the rice flour and place it in a 50 mL plastic centrifuge tube, add 6 mL of the double-distilled water and 10 mL of the sodium acetate buffer solution to the centrifuge tube and perform a water bath.
[0022] Specifically, add double-distilled water and a sodium acetate buffer solution to the powdery test sample, perform a water bath at 37 °C for 5 min, and then add an enzymatic hydrolysate to carry out a digestion reaction at 37 °C.
[0023] Specifically, the preparation method of the enzymatic hydrolysate includes: taking 5 mL of sodium acetate buffer solution, adding 1290 U of α-amylase, 1000 U of glucosidase, and 5 mg of trypsin, and magnetically suspending and stirring in a water bath at 37°C for 10 min.
[0024] Specifically, the absorbance is measured at 505 nm.
[0025] Specifically, the concentration of the glucose standard is 1.099 mg / mL, and W is 100 mg.
[0026] The beneficial effects brought by the technical solution provided by the embodiments of the present disclosure are as follows: The embodiments of the present invention provide a method for predicting the resistant starch content. The correlation coefficient between the resistant starch content data measured by this method and the industry standard method is 0.99, indicating that the prediction method provided by this embodiment can be used as a method for accurately measuring the resistant starch content. At the same time, the method provided by this embodiment calculates the resistant starch content by measuring the content of rapidly digestible starch and slowly digestible starch, and the time is compressed to one-fourth of that of the industry standard method, enabling short-time and efficient measurement. The reagents provided by this embodiment are of low price, reducing the cost of the method provided by this embodiment to one-tenth of that of the industry standard method. Detailed implementation manners
[0027] To make the purpose, technical solutions, and advantages of the present disclosure clearer, the following will further describe the embodiments of the present disclosure in detail.
[0028] Example 1
[0029] The present disclosure provides a method for predicting the resistant starch content, which includes:
[0030] Grind rice into brown rice and then polished rice in sequence;
[0031] Grind the polished rice into rice flour;
[0032] Dry the rice flour;
[0033] Add double-distilled water and sodium acetate buffer solution to the dried rice flour and conduct a water bath;
[0034] Hydrolyze the powdery sample to be tested through a water bath to obtain a hydrolysis product;
[0035] Perform a digestion reaction on the hydrolysis product with an enzymatic hydrolysate to obtain a reaction solution;
[0036] At 0 minute, 20 minutes, and 240 minutes of digestion respectively, take out the reaction solution and add it to an anhydrous ethanol solution to terminate the digestion reaction;
[0037] Measure the glucose content in the taken-out reaction solution;
[0038] Take the glucose standard, the taken reaction solution as the sample, and sodium acetate as the blank control. After adding them to the glucose determination reagent and performing a water bath, place them on an enzyme-linked immunosorbent assay (ELISA) plate and measure the absorbance.
[0039] The hydrolyzed starch content at time t Where Abst is the absorbance, and the hydrolyzed starch content S(t) at time t = G(t) × 0.9 mg.
[0040] The content of rapidly digestible starch Where W is the total mass of the rice flour, and the content of slowly digestible starch
[0041] The resistant starch content RS% = (1 - RDS% - SDS%) × 100%.
[0042] Specifically, the volume ratio of the reaction solution to the anhydrous ethanol solution is 1:9.
[0043] Specifically, the preparation method of the sodium acetate buffer solution includes: taking 90.58 g of sodium acetate trihydrate, adding 300 μL of double-distilled water to dissolve it, adjusting the pH value to 6.0 with glacial acetic acid, and then adding double-distilled water to make up the volume to 500 mL.
[0044] Specifically, pass the rice flour through a 100-mesh sieve and dry the sieved rice flour.
[0045] Specifically, the drying temperature is 42 °C.
[0046] Specifically, weigh 0.1 g of rice flour and place it in a 50 mL plastic centrifuge tube. Add 6 mL of double-distilled water and 10 mL of sodium acetate buffer solution to the centrifuge tube and perform a water bath.
[0047] Specifically, the preparation method of the enzyme digestion solution includes: taking 5 mL of sodium acetate buffer solution, adding 1290 U of α-amylase, 1000 U of glucosidase, and 5 mg of trypsin, and stirring in a magnetic suspension water bath at 37 °C for 10 min.
[0048] Specifically, measure the absorbance at each time at 505 nm.
[0049] Specifically, add double-distilled water and sodium acetate buffer solution to the dried rice flour, perform a water bath at 37 °C for 5 min, and then add the enzyme digestion solution to carry out a digestion reaction at 37 °C.
[0050] Specifically, the concentration of the glucose standard is 1.099 mg / mL, and W is 100 mg.
[0051] Reagent preparation:
[0052] Prepare sodium acetate buffer solution (pH = 6.0): Take 90.58 g of sodium acetate trihydrate (purchased from Shanghai National Medicine Group), add 300 μL of ddH2O to dissolve it, adjust the pH value to 6.0 with glacial acetic acid (purchased from Shanghai National Medicine Group), and then add ddH2O to make up the volume to 500 mL.
[0053] Prepare the enzymatic hydrolysis solution: Take 5 mL of sodium acetate buffer solution, add 1290 U of α-amylase (purchased from Shanghai Yuanye Company), 1000 U of glucosidase (purchased from Shanghai Yuanye Company), and 5 mg of trypsin (purchased from German Sigma-Aldrich), and stir in a magnetic levitation water bath at 37 °C for 10 min to fully dissolve and stabilize.
[0054] The sample to be measured in this example is Youtang rice (gifted by the Crop Breeding and Cultivation Institute of Shanghai Academy of Agricultural Sciences). The Youtang rice used in this example is polished rice. Grind the polished rice of Youtang rice into rice flour with a cyclone mill, pass the rice flour through a 100-mesh sieve to obtain the sieved rice flour. Place the sieved rice flour in an oven at 42 °C for stabilization and measurement.
[0055] Weigh 0.1 g of the rice flour of Youtang rice into a 50 mL plastic centrifuge tube, and make 2 replicates. Add 6 mL of ddH2O and 10 mL of sodium acetate buffer solution to each centrifuge tube. After equilibrating in a magnetic levitation water bath at 37 °C for 5 min, add 5 mL of the pre-prepared enzymatic hydrolysis solution, and carry out starch hydrolysis in a magnetic levitation water bath at 37 °C. At 0 min, 20 min, and 240 min of digestion respectively, use a pipette to take 100 μL of the solution from the reaction solution and add it to 900 μL of absolute ethanol solution, shake well to terminate the digestion reaction. Use a glucose assay kit (purchased from Shanghai Rongsheng Company) to measure the glucose content in the reaction solution. The percentage of hydrolyzed starch = free glucose content × 0.9. Respectively pipette 10 μL of the sample solution, glucose standard, and sodium acetate blank control into a new 1.5 mL centrifuge tube, add 1 mL of glucose assay reagent to the centrifuge tube, incubate in a water bath at 37 °C for 10 min, then pipette 200 μL of the solution into an enzyme-linked immunosorbent assay (ELISA) plate, and measure the absorbance at each time point at 505 nm, and record them as Abst.
[0056] At 0 min of digestion, the average absorbance of the reaction solution of Youtang rice was measured to be 0.06505. At 20 min of digestion, the average absorbance of the reaction solution of Youtang rice was measured to be 0.08482. At 240 min of digestion, the average absorbance of the reaction solution of Youtang rice was measured to be 0.12579, the average absorbance of the blank control (sodium acetate) was 0.06175, and the average absorbance of the glucose standard was 0.2362. According to the formula:
[0057] The hydrolyzed starch content at time t Where Abst is the absorbance, and the hydrolyzed starch content S(t) at time t = G(t) × 0.9 mg,
[0058] Quickly digested starch content Where W is the total mass of the rice flour, slowly digested starch content
[0059] The resistant starch content RS% = (1 - RDS% - SDS%) × 100%.
[0060] According to the above formula, the glucose content of the Youtang rice reaction solution at time t0 is:
[0061]
[0062] The glucose content of the Youtang rice reaction solution at 20 minutes of digestion is:
[0063]
[0064] The hydrolyzed starch content S(20) = G(20) * 0.9 = 35.8125 * 0.9 = 32.2312 mg
[0065] The glucose content of the Youtang rice reaction solution at 240 minutes of digestion is:
[0066]
[0067] The hydrolyzed starch content S(240) = G(240) * 0.9 = 88.6911 * 0.9 = 79.8220 mg
[0068] Calculated:
[0069] Quickly digested starch content of Youtang rice
[0070] Slowly digested starch content of Youtang rice
[0071] The resistant starch content RS% of Youtang rice = (1 - 28.3020% - 47.5908%) * 100% = 24.1072%.
[0072] Using the industry standard method (NY / T 2638 - 2014), the resistant starch content of Youtang rice is measured to be 17.8%. The correlation coefficient of the data measured by the standard method and the prediction method provided in this example is 0.99, indicating that the prediction method provided in this example can be used as an accurate, efficient and low-cost method for quickly measuring the resistant starch content.
[0073] Example 2
[0074] In this example, a reference sample of resistant starch with a mass percentage content of 39% was used as the sample to be measured. 0.1 g of the reference sample of resistant starch with a mass percentage content of 39% was weighed and placed in a 50 mL plastic centrifuge tube, with 2 replicates. 6 mL of ddH2O and 10 mL of sodium acetate buffer were added to each centrifuge tube. After equilibration in a 37 °C magnetic levitation water bath for 5 min, 5 mL of the pre-prepared enzymatic hydrolysis solution was added, and starch hydrolysis was carried out in a 37 °C magnetic levitation water bath. At 0 min, 20 min, and 240 min of digestion respectively, 100 μL of the solution was taken from the reaction solution with a pipette and added to 900 μL of absolute ethanol solution, and shaken well to terminate the digestion reaction. A glucose assay kit was used to measure the glucose content in the reaction solution. The percentage of hydrolyzed starch = free glucose content × 0.9. 10 μL of the sample solution, glucose standard, and sodium acetate blank control were respectively pipetted into new 1.5 mL centrifuge tubes. 1 mL of glucose assay reagent was added to the centrifuge tubes. After a 10 min water bath at 37 °C, 200 μL of the solution was pipetted into an ELISA plate, and the absorbance at each time point was measured at 505 nm, denoted as Abst respectively.
[0075] At 0 min of digestion, the average absorbance of the reaction solution of the resistant starch reference sample was measured to be 0.06455. At 20 min of digestion, the average absorbance of the reaction solution of the resistant starch reference sample was measured to be 0.08631. At 240 min of digestion, the average absorbance of the reaction solution of the resistant starch reference sample was measured to be 0.10972, the average absorbance of the blank control (sodium acetate) was 0.06175, and the average absorbance of the glucose standard was 0.2362. According to the formula:
[0076] Hydrolyzed starch content at time t In the formula, Abst is the absorbance, and the hydrolyzed starch content S(t) at time t = G(t) × 0.9 mg,
[0077] Content of rapidly digestible starch In the formula, W is the total mass of the rice flour, and the content of slowly digestible starch
[0078] Resistant starch content RS% = (1 - RDS% - SDS%) × 100%.
[0079] According to the above formula, the glucose content of the reaction solution of the resistant starch reference sample at t0 was calculated as:
[0080]
[0081] The glucose content of the reaction solution of the resistant starch reference sample at 20 min of digestion was:
[0082]
[0083] The hydrolyzed starch content S(20) = G(20) * 0.9 = 32.4918 * 0.9 = 29.2426 mg,
[0084] At 240 minutes of digestion, the glucose content in the reaction solution of the resistant starch standard sample is:
[0085]
[0086] The hydrolyzed starch content S(240) = G(240) * 0.9 = 68.7541 * 0.9 = 61.8787 mg.
[0087] Calculated:
[0088] The rapidly digestible starch content of the resistant starch standard sample
[0089] The slowly digestible starch content of the resistant starch standard sample
[0090] The resistant starch content RS% of the resistant starch standard sample = (1 - 25.9088% - 32.6361%) * 100% = 41.4551%.
[0091] The resistant starch content of this resistant starch standard sample measured by the row standard method is 38.8%. The correlation coefficient of the data measured by the row standard method and the prediction method provided in this example is 0.99, indicating that the prediction method provided in this example can be used as an accurate, efficient and low-cost method for rapid determination of resistant starch content.
[0092] Example 3
[0093] The sample to be tested in this example is the japonica rice variety Zhonghua 11 (ZH11) of rice, which is a conventional rice variety provided by Wuhan Aidianjing Biotechnology Co., Ltd. The rice ZH11 is ground into brown rice and then polished rice in sequence. The polished rice is ground into rice flour with a cyclone mill, and the rice flour is sieved through a 100-mesh sieve to obtain the sieved ZH11 rice flour. The sieved ZH11 rice flour is placed in an oven at 42 °C for stabilization and waiting for testing.
[0094] Weigh 0.1 g of ZH11 rice flour and place it in a 50 mL plastic centrifuge tube, with 2 replicates. Add 6 mL of ddH2O and 10 mL of sodium acetate buffer to each centrifuge tube. After equilibration in a 37 °C magnetic levitation water bath for 5 min, add 5 mL of the pre-prepared enzymatic hydrolysis solution, and perform starch hydrolysis in a 37 °C magnetic levitation water bath. At 0 min, 20 min, and 240 min of digestion respectively, use a pipette to take 100 μL of the solution from the reaction solution and add it to 900 μL of anhydrous ethanol solution, then shake well to terminate the digestion reaction. Use a glucose assay kit to measure the glucose content in the reaction solution. The percentage of hydrolyzed starch = free glucose content × 0.9. Respectively pipette 10 μL of the sample solution, glucose standard, and sodium acetate blank control into new 1.5 mL centrifuge tubes. Add 1 mL of glucose assay reagent to the centrifuge tubes. After a 10 min water bath at 37 °C, pipette 200 μL of the solution into an enzyme-linked immunosorbent assay (ELISA) plate, and measure the absorbance at each time point at 505 nm, denoted as Abst respectively.
[0095] At 0 min of digestion, the average absorbance of the reaction solution of ZH11 was measured to be 0.06162. At 20 min of digestion, the average absorbance of the reaction solution of ZH11 was measured to be 0.08791. At 240 min of digestion, the average absorbance of the reaction solution of ZH11 was measured to be 0.13644, the average absorbance of the blank control (sodium acetate) was 0.05341, and the average absorbance of the glucose standard was 0.2137. According to the formula:
[0096] Hydrolyzed starch content at time t In the formula, Abst is the absorbance, and the hydrolyzed starch content S(t) at time t = G(t) × 0.9 mg,
[0097] Content of rapidly digestible starch In the formula, W is the total mass of the rice flour, and the content of slowly digestible starch
[0098] Resistant starch content RS% = (1 - RDS% - SDS%) × 100%.
[0099] According to the formula, the glucose content of the ZH11 reaction solution at t0 is calculated as:
[0100]
[0101] The glucose content of the ZH11 reaction solution at 20 min of digestion is:
[0102]
[0103] Hydrolyzed starch content S(20) = G(20) * 0.9 = 49.6741 * 0.9 = 44.7067 mg
[0104] The glucose content of the ZH11 reaction solution at 240 minutes of digestion is:
[0105]
[0106] The hydrolyzed starch content S(240) = G(240) * 0.9 = 119.5489 * 0.9 = 107.5940 mg
[0107] Calculated:
[0108] The rapidly digestible starch content of ZH11
[0109] The slowly digestible starch content of ZH11
[0110] The resistant starch content RS% of ZH11 = (1 - 34.0808% - 62.8873%) * 100% = 3.0319%.
[0111] The resistant starch content of this ZH11 measured by the row standard method is 0.62%. The correlation coefficient of the data measured by the row standard method and the prediction method provided in this example is 0.99, indicating that the prediction method provided in this example can be used as an accurate, efficient and low-cost method for rapid determination of resistant starch content.
[0112] Example 4
[0113] The sample to be tested in this example is the sbe2b gene knockout mutant rice (provided by Wuhan Aidi Jing Biotechnology Co., Ltd.). The sbe2b gene knockout mutant rice is successively milled into brown rice and polished rice, and the polished rice is ground into rice flour with a cyclone mill. The rice flour is sieved through a 100-mesh sieve to obtain the sieved sbe2b gene knockout mutant rice flour. The sieved sbe2b gene knockout mutant rice flour is placed in an oven at 42 °C for stable testing.
[0114] Weigh 0.1 g of the sbe2b gene knockout mutant rice flour and place it in a 50 mL plastic centrifuge tube, with 2 replicates. Add 6 mL of ddH2O and 10 mL of sodium acetate buffer to each centrifuge tube. After equilibrating in a 37°C magnetic levitation water bath for 5 min, add 5 mL of the pre-prepared enzymatic hydrolysis solution, and carry out starch hydrolysis in a 37°C magnetic levitation water bath. At 0 min, 20 min, and 240 min of digestion respectively, use a pipette to take 100 μL of the solution from the reaction solution and add it to 900 μL of anhydrous ethanol solution, shake well to terminate the digestion reaction. Use a glucose assay kit to measure the glucose content in the reaction solution. The percentage of hydrolyzed starch = free glucose content × 0.9. Respectively pipette 10 μL of the sample solution, glucose standard, and sodium acetate blank control into new 1.5 mL centrifuge tubes. Add 1 mL of glucose assay reagent to the centrifuge tubes. After incubating in a 37°C water bath for 10 min, pipette 200 μL of the solution into an enzyme-linked immunosorbent assay (ELISA) plate, and measure the absorbance at 505 nm at each time point, denoted as Abst.
[0115] At 0 min of digestion, the average absorbance of the reaction solution of the sbe2b gene knockout mutant was measured to be 0.06341. At 20 min of digestion, the average absorbance of the reaction solution of the sbe2b gene knockout mutant was measured to be 0.08469. At 240 min of digestion, the average absorbance of the reaction solution of the sbe2b gene knockout mutant was measured to be 0.12939, the average absorbance of the blank control (sodium acetate) was 0.05341, and the average absorbance of the glucose standard was 0.2137. According to the formula:
[0116] Hydrolyzed starch content at time t Where Abst is the absorbance, and the hydrolyzed starch content S(t) at time t = G(t) × 0.9 mg,
[0117] Rapidly digestible starch content Where W is the total mass of the rice flour, slowly digestible starch content
[0118] Resistant starch content RS% = (1 - RDS% - SDS%) × 100%.
[0119] According to the formula, calculate the glucose content of the reaction solution of the sbe2b gene knockout mutant at t0 as:
[0120]
[0121] The glucose content of the reaction solution of the sbe2b gene knockout mutant at 20 min of digestion is:
[0122]
[0123] The hydrolyzed starch content S(20) = G(20) × 0.9 = 45.3402 × 0.9 = 40.8062 mg,
[0124] At 240 minutes of digestion, the glucose content in the reaction solution of the sbe2b gene knockout mutant was:
[0125]
[0126] The hydrolyzed starch content S(240) = G(240) × 0.9 = 109.3981 × 0.9 = 98.4583 mg,
[0127] Calculated:
[0128] The rapidly digestible starch content of the sbe2b gene knockout mutant
[0129] The slowly digestible starch content of the sbe2b gene knockout mutant
[0130] The resistant starch content RS% of the sbe2b gene knockout mutant = (1 - 27.8477% - 57.6521%) × 100% = 14.5002%.
[0131] The resistant starch content of the sbe2b gene knockout mutant measured by the row label method was 8.3%. The correlation coefficient between the data measured by the row label method and the prediction method provided in this example was 0.99, indicating that the prediction method provided in this example can be used as an accurate, efficient and low-cost method for rapid determination of resistant starch content.
[0132] The above are only optional embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present disclosure shall be included within the protection scope of the present disclosure.
Claims
1. A method for predicting the resistant starch content, characterized in that, The method includes: Hydrolyzing the powdery sample to be measured through a water bath to obtain a hydrolysis product; Adding an enzymatic hydrolysis solution to the hydrolysis product for a digestion reaction to obtain a reaction solution; At 0 minute, 20 minutes, and 240 minutes of digestion respectively, taking out the reaction solution and adding it to an absolute ethanol solution to terminate the digestion reaction; Measuring the glucose content in the taken-out reaction solution; Taking a glucose standard, the taken-out reaction solution, and sodium acetate as a blank control, adding a glucose determination reagent respectively, then performing a water bath, and measuring the absorbance; The hydrolyzed starch content at time t where Abst is the absorbance, The hydrolyzed starch content S(t) at time t = G(t) × 0.9 mg; Quick-consumer starch content where W is the total mass of the rice flour Slowly digestible starch content The resistant starch content RS% = (1 - RDS% - SDS%) × 100%; 2. The method for predicting the resistant starch content according to claim 1, wherein The volume ratio of the reaction solution to the absolute ethanol solution is 1:
9.
3. The method for predicting the resistant starch content according to claim 1, characterized in that, The preparation method of the sodium acetate buffer solution includes: taking 90.58 g of sodium acetate trihydrate, adding 300 μL of double-distilled water to dissolve it, adjusting the pH value to 6.0 with glacial acetic acid, and then adding double-distilled water to make up the volume to 500 mL.
4. The method for predicting the resistant starch content according to claim 1, wherein When the sample to be measured is rice, milling the rice to obtain rice flour, passing the rice flour through a 100-mesh sieve, and drying the sieved rice flour to obtain the powdery sample to be measured.
5. The method for predicting the resistant starch content according to claim 4, characterized in that, The temperature of the drying is 42 °C.
6. The method for predicting the resistant starch content according to claim 4, wherein Weighing 0.1 g of the rice flour and placing it in a 50 mL plastic centrifuge tube, adding 6 mL of the double-distilled water and 10 mL of the sodium acetate buffer solution to the centrifuge tube and performing a water bath.
7. The method for predicting the resistant starch content according to claim 1, wherein Adding double-distilled water and a sodium acetate buffer solution to the powdery sample to be measured, performing a water bath at 37 °C for 5 min, and then adding an enzymatic hydrolysis solution to perform a digestion reaction at 37 °C.
8. The method for predicting the resistant starch content according to claim 1, wherein The preparation method of the enzymatic hydrolysis solution includes: taking 5 mL of sodium acetate buffer solution, adding 1290 U of α-amylase, 1000 U of glucosidase, and 5 mg of trypsin, and performing magnetic suspension water bath stirring at 37 °C for 10 min.
9. The method for predicting the resistant starch content according to claim 1, wherein Measuring the absorbance at 505 nm.
10. The method for predicting the resistant starch content according to claim 1, wherein, The concentration of the glucose standard is 1.099 mg / mL, and W is 100 mg.