CN118090690A - Detection method of amylose in grains - Google Patents

Abstract

The invention belongs to the field of food detection, and particularly relates to a detection method of amylose in grains; according to the invention, the amylose in the grains is extracted by using the rare earth metal aqueous solution as the extracting solution and detected by using the fluorescence spectrophotometer, and compared with the method, the method has a good detection effect.

Description

A method for detecting amylose in cereals

Technical Field

The invention belongs to the field of food detection, and in particular relates to a method for detecting amylose in cereals.

Background technique

Starch is a mixture that is made up of different types of starch, one is amylose and the other is amylopectin.

Among them, amylose is the main nutrient component of crops such as wheat, corn, and rice, and has a great impact on the quality and taste of food. Rice with a high amylose content will absorb more water during the cooking process, resulting in fluffy and dark rice grains. The content of wheat amylose directly affects the softness, viscosity, and smoothness of the final flour. At the same time, corn starch is one of the main sources of amylose.

Since amylose has a great influence on the quality of food, the detection of amylose content has important theoretical value and practical significance.

Summary of the invention

The present invention aims to provide a method for detecting amylose in cereals.

The present invention is achieved through the following technical solutions:

A method for detecting amylose in cereals comprises the following steps:

Extraction of crude product: The sample to be tested is crushed and added to a rare earth element aqueous solution, the solution is heated to 60°C and maintained at 60°C for 90 minutes; then 100 mL of a mixed solution of n-butanol and isoamyl alcohol is added; then heated to 100°C and stirred for 10 minutes; cooled to 4°C and maintained at 4°C for 24 hours; finally centrifuged at room temperature for 20 minutes to obtain a crude amylose product;

Purification: 100 mL of a mixed solution of n-butanol and water is added to the crude amylose product, wherein; the solution is heated to 100°C until the starch is completely dissolved, then cooled to 25°C, and then stored in a 4°C environment for 24 hours, centrifuged to obtain a precipitate, and the precipitation treatment is repeated 3 to 4 times; then the precipitate is immersed in anhydrous ethanol for 24 hours, the precipitate is washed with anhydrous ethanol, and vacuum dried to obtain amylose;

The amylose content was then detected using a fluorescence spectrophotometer.

Furthermore, the volume ratio of butanol to isoamyl alcohol in the mixed solution of butanol and isoamyl alcohol is 1:3.

Furthermore, the volume ratio of n-butanol to water in the n-butanol-water mixed solution is 1:9.

Furthermore, the rare earth element in the rare earth element aqueous solution is selected from one of PrCl _3, CeCl _3, PrCl _3, NdCl _{3, and} EuCl ₃ .

Furthermore, the rare earth element in the rare earth element aqueous solution is selected from EuCl3.

Further, the concentration of the EuCl ₃ solution is 0.5M~1.0M.

Further, the concentration of EuCl ₃ solution is 0.5M.

Furthermore, the volume of the EuCl ₃ solution is 70 to 150 mL.

Further, the volume of EuCl ₃ solution is 100 mL.

Furthermore, when the amylose content is detected using a fluorescence spectrophotometer, the maximum excitation wavelength and emission wavelength are determined by scanning in the wavelength range of 300-500 nm.

Compared with the prior art, the present invention has the following advantages and beneficial effects: see the embodiments.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments. The illustrative embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

Example 1

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 100mL of 0.5M CeCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Example 2

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 100mL of 0.5M PrCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Example 3

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 100mL of 0.5M NdCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Example 4

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 100mL of 0.5M EuCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Example 5

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 100mL of 0.5M LaCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Example 6

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 70mL of 0.5M EuCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Example 7

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 80mL of 0.5M EuCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Example 8

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 120mL of 0.5M EuCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Example 9

Extraction of crude product: Take 10g of the sample to be tested, crush it, add it to 150mL of 0.5M EuCl ₃ aqueous solution, heat the solution to 60℃, and keep it at 60℃ for 90min; then add 100mL of a mixed solution of n-butanol and isoamyl alcohol, where the volume ratio of butanol to isoamyl alcohol is 1:3; then heat to 100℃ and stir for 10min; cool to 4℃ and keep it at 4℃ for 24h; finally centrifuge at room temperature for 20min to obtain crude amylose;

Purification: Take 100 mL of a mixed solution of n-butanol and water and add it to the crude amylose product, wherein the volume ratio of n-butanol to water is 1:9; heat the solution to 100°C until the starch is completely dissolved, then cool it to 25°C, and then store it in a 4°C environment for 24 hours, centrifuge it to obtain a precipitate, and repeat the precipitation process 3 to 4 times; then immerse the precipitate in anhydrous ethanol for 24 hours, wash the precipitate with anhydrous ethanol, and vacuum dry it to obtain amylose.

Test Example 1

The methods in Examples 1 to 9 were used to detect the amylose in the same rice. The detection method was to use water as a solvent, use a fluorescence spectrophotometer to detect the amylose content, determine the maximum excitation wavelength and emission wavelength in the range of 300 to 500 nm, and the standard curve concentration range was 0.1 μg/mL to 1.0 μg/mL. At the same time, the detection value of NY/T 55-1987 was used as a standard. Each measurement was performed twice and the average value was taken.

Table 1 Performance test

It can be seen from the data in Table 1 that the extracts of different rare earth elements all have certain effects, but the effect in Example 4 is the best, which is closest to the results measured by the national standard NY/T 55-1987.

Test Example 2

The method of Example 4 was used to detect the contents of different cereals. The detection method was to use water as a solvent, use a fluorescence spectrophotometer to detect the content of amylose, determine the maximum excitation wavelength and emission wavelength in the range of 300-500 nm, and the concentration range of the standard curve was 0.1 μg/mL-1.0 μg/mL. At the same time, the detection value of NY/T 55-1987 was used as a standard. Each measurement was performed twice and the average value was taken.

Table 2 Determination of amylose content in different cereals.

It can be seen from the data in Table 2 that the detection method in this application can be used for the determination of different types of grains.

The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims (10)

1. A method for detecting amylose in grains, comprising the steps of:

Extraction of crude product: crushing a sample to be detected, adding the crushed sample into a rare earth element aqueous solution, heating the solution to 60 ℃, and keeping the temperature at 60 ℃ for 90min; then adding 100mL of mixed solution of n-butanol and isoamyl alcohol; then heating to 100 ℃ and stirring for 10min; cooling to 4 ℃ and maintaining at 4 ℃ for 24 hours; finally, centrifuging for 20min at room temperature to obtain an amylose crude product;

Purifying: adding 100mL of n-butanol water mixed solution into the crude amylose product, wherein; heating the solution to 100 ℃ until starch is completely dissolved, cooling to 25 ℃, placing in an environment of 4 ℃ for 24 hours, centrifuging to obtain a precipitate, and repeatedly treating the precipitate for 3-4 times; immersing the precipitate in absolute ethyl alcohol for 24 hours, washing the precipitate with absolute ethyl alcohol, and then drying in vacuum to obtain amylose;

and detecting the content of the amylose by using a fluorescence spectrophotometer.

2. The method according to claim 1, wherein the volume ratio of butanol to isoamyl alcohol in the butanol and isoamyl alcohol mixed solution is 1:3.

3. The method according to claim 1, wherein the volume ratio of n-butanol to water in the n-butanol-water mixed solution is 1:9.

4. The method of claim 1, wherein the aqueous rare earth element solution contains a rare earth element selected from the group consisting of PrCl _3、CeCl_3、PrCl_3、NdCl_3、EuCl₃.

5. The method of claim 4, wherein the aqueous rare earth element solution contains a rare earth element selected from the group consisting of EuCl3.

6. The method of claim 5, wherein the concentration of the EuCl ₃ solution is 0.5M to 1.0M.

7. The method of claim 6, wherein the concentration of EuCl ₃ solution is 0.5M.

8. The method of claim 7, wherein the volume of EuCl ₃ solution is 70-150 mL.

9. The method of claim 8, wherein the volume of the EuCl ₃ solution is 100mL.

10. The method according to claim 1, wherein the maximum excitation wavelength and emission wavelength are determined by scanning in a wavelength range of 300 to 500nm when detecting the amylose content using a fluorescence spectrophotometer.