Method for extracting characteristic polyphenols in malus asiatica pulp and method for rapidly detecting content of characteristic polyphenols in malus asiatica pulp

Abstract

The invention discloses a method for extracting characteristic polyphenols in malus asiatica pulp and a method for rapidly detecting the content of the characteristic polyphenols, relates to the technical field of food detection, and solves the problem that at present, a method for rapidly and accurately extracting the characteristic polyphenols in the malus asiatica pulp is lacked. In order to solve the technical problems in the prior art, in order to solve the technical problems in the prior art, a special extraction agent and a variable-temperature extraction condition are combined aiming at a specific detection material, namely the malus asiatica pulp, and the characteristic polyphenol is rapidly detected without depending on a high-performance liquid chromatography; the rapid and convenient sample treatment is realized; the quantitative detection on the concentration of the characteristic polyphenol chlorogenic acid and phlorizin is specifically and accurately carried out without depending on the high performance liquid chromatography.

Description

Technical Field

[0001] The present invention belongs to the technical field of food detection, and particularly relates to a method for extracting characteristic polyphenols in Malus asiatica pulp and a rapid detection method for their content. Background Art

[0002] Malus asiatica, also known as Chinese pear-leaved crabapple, is a fruit of the genus Malus. Polyphenolic compounds are important components of its health-benefiting active ingredients and unique flavor. Malus asiatica is not suitable for fresh storage. After picking, it will quickly enter the post-ripening period, and its pulp will change from "crisp" to "soft", and it cannot be stored for a long time for further deep processing. Malus asiatica pulp prepared by steaming with water to remove seeds and then grinding into pulp can be stored frozen for a long time, retaining as much as possible the nutritional and flavor components in fresh Malus asiatica. The characteristic of this Malus asiatica pulp is that the mass ratio of Malus asiatica to water is between 1:2 and 1:3. Since polyphenolic substances are unstable, prone to oxidation and degradation, it is necessary to establish a rapid and relatively accurate detection method to quantitatively analyze the content of characteristic polyphenol components in Malus asiatica pulp in order to control the quality of Malus asiatica pulp. There are mainly 5 polyphenols in Malus asiatica, namely chlorogenic acid, procyanidin B 2 , epicatechin, phloridzin and (+)-catechin. However, after processing, some polyphenol components in Malus asiatica pulp have changed, and some unstable polyphenols have been greatly degraded, but some polyphenols are still retained, forming a characteristic polyphenol composition with chlorogenic acid with a fresh fragrance and phloridzin with a sweet taste as the binary main components. These two characteristic polyphenols are the key nutritional and flavor components that need to be quality-controlled in Malus asiatica pulp. The composition characteristic of this characteristic polyphenol is that chlorogenic acid and phloridzin are the main components. Accurately measuring the concentrations of chlorogenic acid and phloridzin in Malus asiatica pulp can rapidly detect the content of characteristic polyphenols in Malus asiatica pulp.

[0003] Chlorogenic acid is a phenolic acid formed by the condensation of caffeic acid and quinic acid. There are three unstable parts in its molecular structure: an ester bond, an unsaturated double bond and a polyphenol. Previous studies have shown that during the extraction process, it often undergoes isomerization through hydrolysis and intramolecular ester group migration, resulting in its degradation. Due to the instability of chlorogenic acid itself, high temperature, strong light and long-term heating during extraction will all have an adverse impact on its extraction rate and batch stability. Phloridzin is a characteristic dihydrochalcone compound in apples. Both chlorogenic acid and phloridzin will form turbid juice due to the polyphenol / pectin interaction, affecting the spectral characteristics during their ultraviolet absorption spectrum analysis. The boiling process in the preparation of Malus asiatica pulp can release a large amount of pectin components, and Malus asiatica contains a high content of organic acid components, thus forming a complex polyphenol-pectin complex, producing a high-turbidity liquid, which affects the direct detection of its content by ultraviolet spectrophotometry.

[0004] The existing method for accurately extracting and detecting the content of characteristic polyphenols in sand fruit pulp is to first treat the sand fruit pulp sample with pectinase or ultrasound, etc., then extract it with polar solvents such as methanol or ethanol, purify it with or without a solid-phase extraction column, centrifuge or filter it multiple times, and then use a high-performance liquid chromatograph for determination; this method is complicated, costly, requires the use of a high-performance liquid chromatograph, and the sample preparation and analysis time exceed 2 hours, making it impossible to achieve immediate detection, and the throughput is small, making it difficult to detect in batches. For the traditional ultraviolet spectrophotometry method, direct detection or detection after derivatization (such as the Folin-Ciocalteu method), due to the influence of other non-characteristic phenols or other impurities during extraction, it is impossible to accurately detect and quantitatively determine the two components of chlorogenic acid and phloridzin in sand fruit pulp simultaneously and separately, and only the total phenol content can be detected, and the content of characteristic polyphenol components cannot be specifically detected; although the high-performance liquid chromatography method can quickly and accurately detect the content of the characteristic polyphenols chlorogenic acid and phloridzin in sand fruit pulp at present, the price of the high-performance liquid chromatograph is much more expensive and complex than that of the ultraviolet spectrophotometry instrument, and at the same time, the detection cost is higher and the analysis time is longer.

[0005] Therefore, there is a lack of a method that can quickly and accurately extract the characteristic polyphenols in sand fruit pulp and quickly quantitatively detect the components of chlorogenic acid and phloridzin in the characteristic polyphenols without relying on high-performance liquid chromatography. Summary of the Invention

[0006] To solve the above technical problems, the present invention provides a method for extracting and quickly detecting the content of characteristic polyphenols in sand fruit pulp. By targeting this specific test material of sand fruit pulp and using a special combination of extractant and variable-temperature extraction conditions, rapid and convenient sample extraction and treatment can be achieved, and quantitative detection can be specifically carried out without relying on high-performance liquid chromatography.

[0007] The technical solution adopted by the present invention is as follows:

[0008] A method for extracting characteristic polyphenols in sand fruit pulp, comprising the following steps:

[0009] Step A. Take a certain volume of sand fruit pulp and add the pre-prepared extractant to obtain a mixed solution A;

[0010] Step B. Heat the extractant mixed solution to 50 - 70 °C and mix well to obtain a mixed solution B;

[0011] Step C. Cool the mixed solution B, centrifuge it to obtain upper and lower two-phase solutions, and the upper-phase solution is the extract of the characteristic polyphenols in sand fruit pulp.

[0012] Preferably, the extractant in Step A is a water-saturated n-butanol solution containing arginine hydrochloride.

[0013] Preferably, the preparation method of the extractant in step A is as follows: Prepare an aqueous solution of 25 mM arginine hydrochloride with a volume of 1 part, add a n-butanol solution with a volume of 5 parts, mix well, let it stand for liquid separation at room temperature, and take the upper layer to obtain a water-saturated n-butanol solution containing arginine hydrochloride.

[0014] Preferably, the mixing method in step B is to mix by shaking first and then perform ultrasonic treatment.

[0015] Preferably, in step C, the mixture B is quickly cooled in an environment of 0-10°C.

[0016] With the above technical solution, the dissolution of most non-characteristic polyphenols in the n-butanol phase is reduced.

[0017] Preferably, in step C, the centrifugation method is to centrifuge the mixture B in a centrifuge, and the rotation speed of the centrifuge is ≥8000 revolutions per minute.

[0018] A rapid extraction and detection method for the content of characteristic polyphenols in sand fruit pulp includes the following steps:

[0019] Step 1: Obtain the characteristic polyphenol extract of sand fruit pulp based on the above-mentioned extraction method of characteristic polyphenols in sand fruit pulp;

[0020] Step 2: Weigh a certain amount of different masses of chlorogenic acid and phloridzin reference substances respectively and add them to the extractant to prepare standard reference solutions R 绿 and R 根 , using the extractant as the blank reference solvent Blank, and using the external standard method with ultraviolet spectrophotometry to establish standard curve equations SC 绿 at 360 nm and 280 nm respectively for R 绿360 and SC 绿280 ; establish a standard curve equation SC 根 at 280 nm for R 根280 ;

[0021] Step 3: Measure the absorbance values A 360混 and A 280混 of the characteristic polyphenol extract of sand fruit pulp obtained in step 1 and the blank reference solvent Blank described in step 2 at 360 nm and 280 nm respectively;

[0022] Step 4: Directly calculate the chlorogenic acid concentration C 绿360 in the sand fruit pulp according to SC 360混 and A 绿 ;

[0023] Step 5: Calculate the corresponding A 绿 value by back-calculation according to C 绿280 and SC 280绿 ;

[0024] Step 6: According to A 280绿 and A 280混 obtain A 280根 , and according to A 280根 and SC 根280 calculate the phloridzin concentration C 根 in the apple berry pulp.

[0025] Preferably, in Step 6, the A 280根 = A 280混 - A 280绿 .

[0026] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows:

[0027] 1. Chlorogenic acid and phloridzin components are specifically extracted from high-turbidity apple berry pulp; the enrichment rate of characteristic polyphenols is higher, while the interference of non-specific polyphenols and other impurities is reduced, making its specificity stronger.

[0028] 2. The analysis time is significantly reduced, and high-throughput rapid detection can be achieved. The total analysis time for a single sample is less than 30 minutes, and the total analysis time for multiple samples is significantly less than that of the existing high-performance liquid chromatography method.

[0029] 3. The chlorogenic acid and phloridzin components in the characteristic polyphenol extract of apple berry pulp can be directly analyzed by ultraviolet spectrophotometry without derivatization sample treatment or other treatments, and its accuracy can reach the range of 100 ± 20% of the chlorogenic acid and phloridzin contents in the characteristic polyphenols of apple berry pulp measured by high-performance liquid chromatography. It is possible to achieve simultaneous rapid quantitative analysis of the characteristic polyphenols chlorogenic acid and phloridzin in apple berry pulp only by using ultraviolet spectrophotometry without relying on high-performance liquid chromatography. Description of the Drawings

[0030] The present invention will be described by way of examples with reference to the drawings, where:

[0031] Figure 1 is the three-wavelength superposition chromatogram obtained by detecting the characteristic polyphenol extract solution of apple berry pulp S1 by high-performance liquid chromatography at 280 nm, 325 nm and 360 nm respectively in Comparative Example 1.

[0032] Figure 2 is the ultraviolet absorption spectrum of chlorogenic acid and phloridzin standards. Detailed Embodiments

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly and completely describe the technical solutions of this application in conjunction with the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope protected by this application.

[0034] The following will make a detailed description of this application in conjunction with Figures 1 - 2 to this application.

[0035] Example 1

[0036] Extraction of characteristic polyphenols in Malus sieversii (Ledeb.) Roem. fruit pulp;

[0037] Take 1 volume portion of the Malus sieversii (Ledeb.) Roem. fruit pulp sample S1 in a centrifuge tube, and add 20 volume portions of arginine hydrochloride water-saturated n-butanol solution as the extraction solution. The preparation method of this arginine water-saturated n-butanol solution is as follows: Prepare 1 volume portion of 25 mM arginine hydrochloride aqueous solution, add 5 volume portions of n-butanol solution and mix evenly, let it stand for liquid separation at room temperature, and take the upper phase as the arginine hydrochloride water-saturated n-butanol solution; heat the mixture of Malus sieversii (Ledeb.) Roem. fruit pulp and the above extraction solution to 60 °C in a water bath and shake it evenly, place it in a 60 °C ultrasonic water bath for ultrasonic treatment for 10 minutes, then quickly cool it in a 5 °C water bath and then place it in a centrifuge at room temperature and centrifuge at a speed of more than 8000 revolutions per minute for 10 minutes to obtain obviously layered upper and lower two-phase solutions. Take a part of the upper phase solution S (i.e., the characteristic polyphenol extract of Malus sieversii (Ledeb.) Roem. fruit pulp), and detect the characteristic polyphenol extract of Malus sieversii (Ledeb.) Roem. fruit pulp by dual-wavelength ultraviolet spectrophotometry.

[0038] Detection by dual-wavelength ultraviolet spectrophotometry;

[0039] Refer to the appendix Figure 2 , weigh 0.02, 0.05, 0.1, 0.2, 0.4, 0.8, 1.6 mg of chlorogenic acid and phloridzin reference substances respectively, and configure them into standard reference solutions of 0.4, 1, 2, 4, 8, 16, 32 μg / ml respectively with 50 ml of arginine hydrochloride water-saturated n-butanol solution as the solvent, denoted as R 绿1-7 and R 根1-7 , use arginine hydrochloride water-saturated n-butanol solution as the blank reference solvent Blank, and establish standard curve equations SC 绿 at 360 nm and 280 nm for R 绿360 and SC 绿280 , and establish standard curve R 根 at 280 nm for R 根280;The absorbance values A were measured for the obtained upper-phase solution S (characteristic polyphenol extract of Malus sieversii fruit pulp) and the above blank reference solvent Blank at 360 nm and 280 nm respectively. 360混 and A 280混 .

[0040] Among them, the linear correlation coefficient R values of SC 绿360 , SC 绿280 and R 根280 are all in the range of 0.998 - 1.000, and the linear range is between 0.4 - 32 μg / ml.

[0041] The concentration C of chlorogenic acid in Malus sieversii fruit pulp 绿 is directly calculated according to SC 绿360 and A 360混 . And according to C 绿 , the corresponding A 绿280 value is calculated inversely using SC 280绿 .

[0042] The concentration C of phloridzin in Malus sieversii fruit pulp 根 is calculated according to SC 根 and A 280根 , where:

[0043] A280 根 = A 280混 - A 280绿 .

[0044] The total analysis time is recorded as the total duration from the start of processing a single sample to obtaining the data, and the analysis time is 28 minutes.

[0045] Example 2

[0046] According to the preparation method of the characteristic polyphenol extract of Malus sieversii fruit pulp in Example 1, for representative Malus sieversii fruit pulp samples S1 - S4 of different batches or origins (where S1 and S2 are samples of two batches from the same origin, and S3, S4 and S1 / S2 are samples from three different origins), the extraction solution was prepared simultaneously, and the double-wavelength ultraviolet spectrophotometry method in Example 1 was used for detection. Three parallel repeated samples were detected, and the average values of the characteristic polyphenol content in each sample were obtained respectively. The total analysis time is recorded as the total duration from the start of processing the samples to obtaining the data, and the total analysis time is 37 minutes.

[0047] Comparative Example 1

[0048] Analysis by high performance liquid chromatography;

[0049] The samples and extraction methods of the characteristic polyphenols in Malus sieversii fruit pulp are the same as those in Example 2;

[0050] Refer to Appendix Figure 1, the detection method for characteristic polyphenols in crabapple pulp is as follows: Waters H-CLASS high performance liquid chromatograph with a PDA detector, detection wavelengths of 280 nm, 325 nm and 360 nm, the chromatographic column is Waters HSS T3 100 mm * 2.1 mm * 1.8 μm, and the mobile phase is gradient elution with ammonium formate / formic acid aqueous solution and acetonitrile. Three replicate samples were detected in parallel, and the content values of characteristic polyphenols in crabapple pulp were obtained by the external standard method.

[0051] The total time taken for the analysis was recorded as the total duration from the start of sample processing to obtaining the data, and the total analysis time was 390 minutes.

[0052] Comparative Example 2

[0053] The sample of characteristic polyphenols in crabapple pulp was the same as in Example 1; and the extraction method referred to the extraction method of crabapple polyphenols described in Lian Xiaoxing, Zhu Ruonan, Wu Hongqin, et al. Extraction and composition analysis of crabapple polyphenols [J]. Biomass Chemical Engineering, 2022(003):056.DOI:10.3969 / j.issn.1673-5854.2022.03.005. to obtain the total polyphenol extract of crabapple pulp.

[0054] The analysis method was the same as in Comparative Example 1. The total polyphenol extract of crabapple pulp was analyzed by the high performance liquid chromatography method in Comparative Example 1 and by the ultraviolet spectrophotometry method in Example 1, and the content values of characteristic polyphenols in crabapple pulp were obtained by the external standard method.

[0055] Comparative Example 3

[0056] Extraction of characteristic polyphenols in crabapple pulp;

[0057] Take 1 volume portion of crabapple pulp sample S1 in a centrifuge tube, add 20 volume portions of water-saturated n-butanol solution. The preparation method of this water-saturated n-butanol solution is: 1 volume portion of aqueous solution, add 5 volume portions of n-butanol solution and mix well, let it stand for liquid separation at room temperature, and take the upper phase as the water-saturated n-butanol solution; heat the mixture of crabapple pulp and the above water-saturated n-butanol solution to 60 °C in a water bath and shake well, place it in a 60 °C ultrasonic water bath for ultrasonic treatment for 10 minutes, then quickly cool it in a 5 °C water bath, and centrifuge it in a centrifuge at room temperature at a speed of more than 8000 revolutions per minute for 10 minutes to obtain clearly layered upper and lower two-phase solutions. Take a part of the upper phase solution S (i.e., the characteristic polyphenol extract of crabapple pulp) for double-wavelength ultraviolet spectrophotometry detection, and the detection method is the same as in Example 1.

[0058] Comparative Example 4

[0059] Extraction of characteristic polyphenols in crabapple pulp;

[0060] Take 1 volume portion of the sand fruit pulp sample S1 in a centrifuge tube, and add 20 volume portions of a saturated n-butanol solution of arginine hydrochloride. The preparation method of this saturated n-butanol solution of arginine hydrochloride is the same as that in Example 1; heat the mixture of the sand fruit pulp and the above-mentioned saturated n-butanol solution of arginine hydrochloride to 60 °C in a water bath and shake well, place it in an ultrasonic water bath at 60 °C for ultrasonic treatment for 10 minutes, then take it out and place it on the table until it reaches room temperature, and place it in a centrifuge at room temperature and centrifuge at a speed of 8000 revolutions per minute or more for 10 minutes to obtain an upper and a lower two-phase solution with obvious stratification. Take a part of the upper-phase solution S (i.e., the characteristic polyphenol extract of the sand fruit pulp) for detection by double-wavelength ultraviolet spectrophotometry, and the detection method is the same as that in Example 1.

[0061] It can be seen from the analysis time-consuming of Examples 1, 2 and Comparative Example 1 that the method adopted by the present invention is more suitable for batch high-throughput analysis, and the required analysis time is significantly reduced compared with the high-performance liquid chromatography method.

[0062] Extract and detect the characteristic polyphenols in the sand fruit pulp samples according to the methods of Examples 1, 2 and Comparative Examples 1 and 2 respectively, and detect 3 replicates in parallel, and measure the chlorogenic acid concentration C 绿 and the phloridzin concentration C 根 values (M±SD), and the detected data are as follows in the table:

[0063] Table 1 Data record table of detecting characteristic polyphenols in sand fruit pulp of different samples by different methods (n = 3)

[0064]

[0065] It can be concluded from the data in Table 1 that the technical route adopted by the present invention can obtain sensitivity and reproducibility similar to those of the high-performance liquid chromatography method, and its accuracy can reach the range of 100±20% of the contents of chlorogenic acid and phloridzin, the characteristic polyphenols of the sand fruit pulp measured by the high-performance liquid chromatography method. The sample extraction and treatment method adopted by the present invention has a better enrichment and extraction effect on the characteristic polyphenols in the sand fruit pulp. It can be concluded from the data in Table 1 that when extracting by a method different from the present invention disclosed by predecessors, its selectivity for the characteristic polyphenols in the sand fruit pulp is insufficient compared with this method. Although the high-performance liquid chromatography method can still accurately quantify the characteristic polyphenols in the sand fruit pulp, it shows a large error value in the ultraviolet spectrophotometry analysis.

[0066] Table 2 Data record table of detecting characteristic polyphenols in sand fruit pulp of different samples by different extraction methods Sample (n = 3)

[0067]

[0068] From the data in Table 2, it can be concluded that to achieve specificity and accuracy close to those of high performance liquid chromatography under ultraviolet spectrophotometry, the optimized reagents and extraction steps need to be adopted. When the extraction reagent in the method described in the present invention is changed or the rapid cooling step is lacking, the selectivity for the characteristic polyphenols in the sand fruit pulp is poor or the extraction efficiency decreases. Although high performance liquid chromatography can still be used to accurately quantify the characteristic polyphenols in the sand fruit pulp, a large error value is shown in the ultraviolet spectrophotometry analysis. For example, when the components extracted by the extraction method in Comparative Example 4 in Table 2 are analyzed by the ultraviolet spectrophotometry method described in Example 1 and compared with Comparative Example 1 using high performance liquid chromatography, it can be seen that the components with more non-chlorogenic acid or phloridzin will cause a significant increase in the ultraviolet spectrophotometry analysis, resulting in a decrease in the specificity and accuracy of this method, which is not an indication of improved extraction efficiency. At the same time, when the components extracted by the extraction method in Comparative Example 3 are analyzed by the ultraviolet spectrophotometry method described in Example 1, due to its lower extraction efficiency than the method described in Example 1, there will be a deficiency of simultaneous decrease in the extraction rate and accuracy.

[0069] It can be seen from the attached Figure 1 that under the extraction method adopted in the present invention, two components with very different chemical structures, chlorogenic acid and phloridzin, in the sand fruit pulp can be enriched with strong selectivity. Whether at 280 nm or 360 nm, there are very few chromatographic peaks other than chlorogenic acid and phloridzin. At the maximum absorption wavelength of chlorogenic acid, 325 nm, multiple impurity peaks can be clearly seen, but these impurity peaks have almost no absorption peaks at 280 nm and 360 nm, indicating that the extraction method for the characteristic polyphenols in the sand fruit pulp provided by the present invention has strong specificity at 280 nm and 360 nm. At the same time, it can be seen from the attached Figure 2 that chlorogenic acid and phloridzin have ultraviolet absorption spectral characteristics with significantly different characteristics. Under the condition of selectively enriching chlorogenic acid and phloridzin and not selectively enriching impurities with similar spectral characteristics, simultaneous dual-wavelength quantitative detection of them can be achieved using the ultraviolet absorption spectrum.

[0070] In summary, without using high performance liquid chromatography, the technical method proposed by the present invention can achieve relatively accurate detection of the characteristic polyphenols, chlorogenic acid and phloridzin, in the sand fruit pulp, reaching accuracy and repeatability similar to those of high performance liquid chromatography, while significantly reducing the analysis time and cost.

[0071] It should be noted that:

[0072] The foregoing description of the disclosed embodiments enables those skilled in the art to practice or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for extracting characteristic polyphenols from sand fruit pulp, characterized in that, it comprises the following steps: Step A. Take a certain volume of sand fruit pulp and add a pre-prepared extractant to obtain a mixture A; Step B. Heat the extractant mixture to 50-70 °C and mix evenly to obtain a mixture B; Step C. Cool the mixture B, and after centrifugation, obtain upper and lower two-phase solutions, wherein the upper-phase solution is the characteristic polyphenol extract of sand fruit pulp.

2. The method for extracting characteristic polyphenols from sand fruit pulp according to claim 1, characterized in that: The extractant in Step A is a water-saturated n-butanol solution containing arginine hydrochloride.

3. The method for extracting characteristic polyphenols from sand fruit pulp according to claim 1, characterized in that: The preparation method of the extractant in Step A is: Prepare 1 volume part of 25 mM arginine hydrochloride aqueous solution, add 5 volume parts of n-butanol solution and mix evenly, let it stand for liquid separation at room temperature, and take the upper phase to obtain the water-saturated n-butanol solution containing arginine hydrochloride in this solution.

4. The method for extracting characteristic polyphenols from sand fruit pulp according to claim 1, characterized in that: The mixing method in Step B is to first mix by shaking and then perform ultrasonic treatment.

5. The method for extracting characteristic polyphenols from sand fruit pulp according to claim 1, characterized in that: In Step C, the mixture B is quickly cooled in an environment of 0-10 °C.

6. The method for extracting characteristic polyphenols from sand fruit pulp according to claim 1, characterized in that: The centrifugation method in Step C is to place the mixture B in a centrifuge for centrifugation, and the rotation speed of the centrifuge is ≥ 8000 revolutions per minute.

7. A rapid extraction and detection method for the content of characteristic polyphenols in sand fruit pulp, characterized in that, it comprises the following steps: Step 1: Obtain the characteristic polyphenol extract of sand fruit pulp based on the method for extracting characteristic polyphenols from sand fruit pulp described in any one of claims 1 to 6; Step 2: Weigh a certain amount of different masses of chlorogenic acid and phloridzin reference substances respectively, add them to the extractant to prepare standard reference solutions R with different concentrations 绿 and R 根 , using the extractant as the blank reference solvent Blank, and using the external standard method with ultraviolet spectrophotometry to establish standard curve equations SC 绿 at 360 nm and 280 nm respectively for R 绿360 and SC 绿280 ; for R 根 establish a standard curve equation SC 根280 at 280 nm; Step 3: Measure the absorbance values A and A at 360 nm and 280 nm respectively for the characteristic polyphenol extract of the Malus sieversii fruit pulp obtained in Step 1 and the blank reference solvent Blank described in Step 2 360混 and A 280混 ; Step 4: According to SC 绿360 and A 360混 directly calculate to obtain the chlorogenic acid concentration C in the shaguo fruit pulp 绿 ; Step 5: Based on C 绿 and SC 绿280 back-calculate the corresponding A 280绿 value; Step 6: According to A 280绿 and A 280混 obtain A 280根 , and according to A 280根 and SC 根280 calculate the phloridzin concentration C 根 .

8. The rapid extraction and detection method for the content of characteristic polyphenols in sand fruit pulp according to claim 7, characterized in that: In step 6, the said A 280根 = A 280混 - A 280绿 .

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