Method for evaluating processing technology of honey-fried loquat leaves based on chroma value

Abstract

The application provides a method for evaluating processing technology of honey-fried loquat leaves based on chroma values, and belongs to the technical field of traditional Chinese medicine processing. The application comprises the following steps: (1) detecting CIELab chroma values L, a and b of the honey-fried loquat leaves by using a color difference meter, and calculating Eab; (2) simultaneously determining the contents of 5-hydroxymethyl furfural, oleanolic acid and ursolic acid by using an HPLC detection method; (3) calculating a comprehensive score OD value by using an AHP-entropy weight method combination weighting; (4) when the OD value is greater than or equal to 90, the L value is 40-60, and the a value is 5-15, the honey-fried loquat leaves prepared under the process are qualified products. The application first establishes an objective quantification method for the processing endpoint of the honey-fried loquat leaves based on CIELab chroma parameters, and OPLS-DA confirms that the VIP values of L, a, b and Eab are all greater than 1, so that the subjective defects of the prior art depending on sensory evaluation are overcome.

Description

Technical Field

[0001] This invention belongs to the field of traditional Chinese medicine processing technology, and in particular relates to a method for evaluating the processing technology of honey-processed loquat leaves based on color values. Background Technology

[0002] Loquat leaves are the dried leaves of *Eriobotrya japonica* (Thunb.) Lindl., a plant in the Rosaceae family, and are listed in the *Pharmacopoeia of the People's Republic of China* (2025 edition). They are known for their lung-clearing, cough-relieving, and nausea-relieving effects. Honey-processed loquat leaves have enhanced lung-moistening and cough-relieving effects after being processed with honey, and are mainly used for dry coughs with little phlegm.

[0003] There are existing reports on the processing technology of loquat leaves. CN102872225A discloses a processing method for honey-processed loquat leaves, which uses the content of a single component as the evaluation index; related literature (Hu Yu, Ma Yule, Guo Zhijun, et al. Optimization of honey-processed loquat leaf processing technology by orthogonal experiment [J]. Central South Agricultural Science and Technology, 2023, 44(8):68-70+76.) uses orthogonal experiment to optimize the honey-processed loquat leaf process, using ursolic acid content as the evaluation index, without examining the change of Maillard reaction product 5-HMF during the processing, and without establishing a correlation model between color parameters and internal quality. The main shortcomings of the above-mentioned existing technologies are reflected in three aspects: (1) The judgment of the processing endpoint lacks objective quantitative means. Current production judges the endpoint by sensory color evaluation ("yellow-brown color"), which is highly subjective and has poor batch repeatability. There are no reports on using CIELab color parameters to objectively quantify the degree of processing of honey-processed loquat leaves. (2) Single quality evaluation index. Existing studies focus on triterpenoid components (oleanolic acid, ursolic acid, He Jingjing, Jiang Guiyu, Luo Qinyu, et al. Study on processing technology of honey-processed loquat leaves [J]. Chinese Traditional and Folk Medicine, 2023, 32(21):48-54.), neglecting the value of the Maillard reaction-specific product 5-HMF as a marker of the degree of processing, and failing to establish a multi-index evaluation system that comprehensively reflects the quality of processing. (3) Insufficient systematicness of process optimization methods. Existing processes mostly adopt orthogonal experiments, which cannot effectively reveal the interaction effects between factors, and lack system optimization and multi-index combination weighted evaluation based on response surface methodology.

[0004] Therefore, establishing a method for processing honey-fried loquat leaves based on colorimetric quantification and multi-index comprehensive evaluation has significant technical value and practical significance. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method for evaluating the processing technology of honey-processed loquat leaves based on color values.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a method for evaluating the processing technology of honey-processed loquat leaves based on colorimetric values, comprising the following steps: (1) The CIELab colorimetric value L of honey-processed loquat leaves was determined using a colorimeter. a b Perform detection and calculate E ab; (2) The contents of 5-hydroxymethylfurfural (5-HMF), oleanolic acid and ursolic acid were simultaneously determined by HPLC. (3) The AHP-entropy weighting method is used to calculate the comprehensive score OD value; (4) When the OD value is ≥90 and L Values ​​are 40-60, a When the value is 5-15, the honey-processed loquat leaves prepared under this process are qualified products; The formula for calculating the OD value is: OD = Σ(Wi × normalized content i × 100), Where Wi is the combined weight of the i-th indicator.

[0007] Preferably, the colorimeter is tested under the following conditions: D65 light source and 10° observation angle.

[0008] As a preferred embodiment, the processing method of the honey-processed loquat leaves is as follows: after crushing the loquat leaf slices, mix them with honey liquid, let them soak for 0.5 to 1.5 hours, stir-fry them at 120 to 160°C for 15 to 25 minutes, cool, dry, and crush them to obtain honey-processed loquat leaves.

[0009] Preferably, the honey liquid is prepared by mixing refined honey and water at a mass ratio of 2 to 4:1.

[0010] Preferably, the amount of refined honey used is 15-25g of refined honey per 100g of loquat leaf slices.

[0011] Preferably, the processing method of honey-fried loquat leaves also includes measuring the color value L of the fried loquat leaves. a The detection, when L The value is 40~60 and a When the value is 5~15, cooling, drying, and pulverizing processes are performed; when L Value and a The value does not conform to L Values ​​are 40-60, a When the value is 5 to 15, continue with the soaking and stir-frying process.

[0012] Preferably, the E The formula for calculating ab is: E ab = (L) 2 +a 2 +b 2 )^(1 / 2).

[0013] Preferably, the detection conditions of the HPLC method are as follows: a C18 column is used, the mobile phase is acetonitrile-0.1% phosphoric acid water gradient elution, the flow rate is 0.6 mL / min, and the detection wavelength is 300 nm for 5-hydroxymethylfurfural, and the detection wavelength is 210 nm for oleanolic acid and ursolic acid.

[0014] As a preferred combination, the combined weight of oleanolic acid and ursolic acid is 0.7675, and the combined weight of 5-hydroxymethylfurfural is 0.2325.

[0015] Preferably, the formula for calculating Wi is: Wi = (Wai × Wei) / Σ(Wai × Wei); Where Wai is the AHP weight and Wei is the entropy weight.

[0016] Compared with the prior art, the present invention has the following beneficial effects: (1) This invention addresses the technical deficiencies in existing technologies, such as the lack of objective colorimetric quantification methods for the endpoint of honey-processed loquat leaves, the single quality evaluation index (not including 5-HMF), and insufficient systematic optimization of process parameters. It provides a method for comprehensively evaluating the processing technology of honey-processed loquat leaves based on CIELab colorimetric quantification and AHP-entropy weight method. Compared with existing technologies, this invention establishes for the first time an objective quantitative method for the endpoint of honey-processed loquat leaves based on CIELab colorimetric parameters. OPLS-DA confirms L... a b E The VIP values ​​of ab are all greater than 1, overcoming the subjective defects of existing technologies that rely on sensory evaluation.

[0017] (2) This invention is the first to incorporate the Maillard reaction-specific product 5-HMF into the quality evaluation index system of honey-processed loquat leaves, which makes up for the shortcomings of existing technologies that ignore the markers of the degree of processing; the AHP-entropy weight method combined weighting takes into account both subjective and objective information, and the evaluation results are more scientific and reasonable.

[0018] (3) The present invention uses the Box-Behnken response surface methodology to reveal the interaction effect between factors (wetting time × honey-water ratio, F=4.63, P=0.0494), overcoming the limitation that existing orthogonal experiments cannot effectively reveal the interaction effect; the OD value of 3 batches was 96.74 (RSD=1.01%), and the process repeatability was significantly better than the existing empirical preparation method. Attached Figure Description

[0019] Figure 1 This is a flowchart illustrating the honey-processing technique for loquat leaves according to the present invention. Figure 2 This is a flowchart illustrating the quality evaluation process for honey-processed loquat leaves according to the present invention. Figure 3 A hierarchical clustering (HCA) tree diagram of the colorimetric values ​​of 26 samples (raw product S0 and processed products S1 to S25); Figure 4 The dispersion plot (R) obtained by PCA of chromaticity parameters and chemical composition. 2 X=0.967, Q 2 =0.812); Figure 5 A bar chart of VIP values ​​for the OPLS-DA model (R 2 X=0.983, R 2 Y=0.674, Q 2 =0.542); Figure 6 The response surface plot of the interaction between the soaking time (A) and the honey-to-water ratio (B) is shown (F=4.63, P=0.0494). Detailed Implementation

[0020] This invention discloses a method for evaluating the processing technology of honey-processed loquat leaves based on colorimetric values, comprising the following steps: (1) The CIELab colorimetric value L of honey-processed loquat leaves was determined using a colorimeter. a b Perform detection and calculate E ab; (2) The contents of 5-hydroxymethylfurfural, oleanolic acid and ursolic acid were determined simultaneously by HPLC. (3) The AHP-entropy weighting method is used to calculate the comprehensive score OD value; (4) When the OD value is ≥90 and L Values ​​are 40-60, a When the value is 5-15, the honey-processed loquat leaves prepared under this process are qualified products; The formula for calculating the OD value is: OD = Σ(Wi × normalized content i × 100), Where Wi is the combined weight of the i-th indicator.

[0021] In this invention, the CIELab colorimetric value L of honey-processed loquat leaves is measured using a colorimeter. a b Perform detection and calculate E ab; Preferably, the CIELab colorimetric value L of honey-processed loquat leaves was detected using a colorimeter under D65 light source and 10° observation angle conditions. a b According to E ab = (L) 2 +a 2 +b 2 )^(1 / 2) calculates the total color value.

[0022] In this invention, the processing method of honey-processed loquat leaves is as follows: Loquat leaf slices are pulverized and mixed with honey solution. After soaking for 0.5-1.5 hours, they are stir-fried at 120-160℃ for 15-25 minutes, cooled, dried, and pulverized to obtain honey-processed loquat leaves. Preferably, the loquat leaf slices are dried to constant weight, pulverized, and passed through a No. 3 pharmacopoeia sieve to obtain loquat leaf powder. Honey solution is evenly poured into the loquat leaf powder and mixed well. After sealing and soaking at 20-25℃ for 0.5-1.5 hours, the mixture is stir-fried at 120-160℃ for 15-25 minutes. The colorimetric value (L) of the stir-fried loquat leaves is measured using a colorimeter. a The detection, when L The value is 40~60 and a When the value is 5-15, the leaves are cooled, dried, and pulverized to obtain roasted loquat leaves; when L... Value and a The value does not conform to L Values ​​are 40-60, a If the value is between 5 and 15, continue the soaking and stir-frying process until the color value L is reached. The value is 40~60 and a The value is 5-15. The preparation method of the honey liquid is as follows: refined honey and water are mixed at a mass ratio of 2-4:1, preferably 2.5-3.5:1, and more preferably 3:1. The amount of refined honey used is 15-25g of refined honey / 100g of loquat leaf slices, preferably 17-22g, and more preferably 20g. The soaking time is preferably 0.75-1.25h, and more preferably 1h; the frying temperature is preferably 130-150℃, more preferably 140℃, and the frying time is preferably 17-22min, and more preferably 20min.

[0023] In this invention, HPLC is used to simultaneously determine the contents of 5-hydroxymethylfurfural, oleanolic acid, and ursolic acid. The detection conditions for the HPLC method are as follows: a C18 column is used; the mobile phase is acetonitrile-0.1% phosphoric acid aqueous gradient elution; the flow rate is 0.6 mL / min; and the detection wavelength is 300 nm for 5-hydroxymethylfurfural; while the detection wavelength is 210 nm for oleanolic acid and ursolic acid. The gradient elution procedure is shown in Table 1.

[0024] Table 1 Gradient elution program

[0025] In this invention, the total combined weight of oleanolic acid and ursolic acid is 0.7675, and the combined weight of 5-hydroxymethylfurfural is 0.2325.

[0026] In this invention, the formula for calculating Wi is: Wi = (Wai × Wei) / Σ(Wai × Wei); where Wai is the AHP weight and Wei is the entropy weight.

[0027] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0028] Example 1: Preparation of Honey-Fried Loquat Leaves

[0029] Ingredients: Loquat leaf slices (produced in Bozhou, Anhui Province, identified as dried leaves of Eriobotrya japonica, a plant of the Rosaceae family, conforming to the standards of the 2025 edition of the Pharmacopoeia of the People's Republic of China); refined honey; purified water.

[0030] according to Figure 1 The method for preparing honey-glazed loquat leaves is as follows: (1) Take loquat leaf slices, dry them in a 60℃ forced-air drying oven until constant weight, pulverize them, pass them through a No. 3 pharmacopoeia sieve (0.355mm aperture), and collect the powder.

[0031] (2) Take the refined honey and dilute it with purified water at a ratio of refined honey to water of 3:1 (by mass), and stir well. Use 20g of refined honey for every 100g of loquat leaf slices.

[0032] (3) Pour the honey liquid evenly into the loquat leaf powder, mix thoroughly, and place in a sealed container to moisten at room temperature (20~25℃) for 1.0h.

[0033] (4) Place the moistened material into a stir-frying machine (C22-F9 type) and stir-fry continuously at 140℃ for 20 minutes until it is no longer sticky and the surface is uniformly yellowish-brown or reddish-brown; use a colorimeter to detect the color difference in real time. Values ​​40-60 and a Stop frying when the temperature is between 5 and 15.

[0034] (5) Take it out, let it cool naturally, dry it at 60°C to constant weight, crush it, pass it through a No. 3 pharmacopoeia sieve, seal it and store it away from light to obtain honey-fried loquat leaves.

[0035] Example 2

[0036] according to Figure 2 The method described in Example 1 is used to evaluate the quality of the honey-processed loquat leaves obtained by the processing method in Example 1, in order to determine whether the processing technology in Example 1 can produce qualified honey-processed loquat leaves. The specific steps are as follows: (1) Colorimetric test: Take honey-processed loquat leaf powder, spread it evenly on weighing paper (about 5 mm thick), and measure the L using a DS-200 colorimeter (D65 light source, 10° observation angle). a b Calculate E by taking the average of the three parallel trials. ab = (L) 2 +a 2 +b 2 )^(1 / 2).

[0037] (2) HPLC detection: C18 column (4.6 mm × 250 mm, 5 μm), mobile phase acetonitrile-0.1% phosphoric acid water gradient elution (elution program see Table 1), flow rate 0.6 mL / min, column temperature 25℃, 5-HMF detected at 300 nm, oleanolic acid and ursolic acid detected at 210 nm, 10 μL of sample injected.

[0038] Sample preparation: Take 1.0 g of powder, add 60% ethanol (solid-to-liquid ratio 1:25 g / mL), reflux in a 70℃ water bath twice (2 h + 1 h), and filter through a 0.45 μm filter membrane. Methodology: Linear R 2 >0.999, precision / stability / reproducibility RSD <2.0%, recovery rate 97%~101%.

[0039] (3) OD value calculation: Wi=(Wai×Wei) / Σ(Wai×Wei), combined weight: total weight of triterpenic acid 0.7675, weight of 5-HMF 0.2325; OD=Σ(Wi×normalized content i×100).

[0040] Upon testing, the honey-processed loquat leaves obtained by the method in Example 1 showed L... It is 50.0, a The OD value is 96.74; OD≥90 and the color parameters are within the specified range, indicating that the loquat leaves prepared using the process of Example 1 can obtain qualified honey-processed loquat leaves.

[0041] Example 3: Box-Behnken Response Surface Process Optimization

[0042] Four variables were selected as the factors of investigation: soaking time (A), honey-to-water ratio (B), frying temperature (C), and frying time (D). The process parameters were optimized using Box-Behnken design combined with response surface methodology. Statistical analysis was performed using DesignExpert 13 software. The response surface experimental factors and their levels are shown in Table 2.

[0043] Table 2. Factors and Levels in Response Surface Experiment

[0044] Using the overall OD value of the content of 5-hydroxymethylfurfural, oleanolic acid, and ursolic acid in honey-processed loquat leaves as the evaluation index, a four-factor, three-level response surface methodology experimental design was designed. The experimental design and results are shown in Table 3.

[0045] Table 3 Response Surface Experimental Design and Results

[0046] Based on the response surface methodology results, the regression equation is: Y = 90.75 - 2.48A + 0.3008B + 5.98C - 0.0375D + 8.39AB + 2.21AC - 3.08AD + 0.0925BC + 1.82BD + 5.00CD - 12.32A 2 -12.50B 2 -1.03C 2 -11.49D 2 .

[0047] Analysis of variance: Model F=3.86, P=0.0082<0.05; lack of fit P=0.1502>0.05, indicating a good fit. Influence of factors: frying temperature > soaking time > honey-to-water ratio > frying time; A×B interaction was the most significant (…). Figure 6 F=4.63, P=0.0494<0.05). Optimal process (rounded): soaking for 1.0 h, honey-to-water ratio 3:1, 140℃, 20 min.

[0048] Example 4 Process Validation

[0049] Three batches of samples (50g each) were prepared in parallel using the method of Example 1. The OD value and L of each batch of samples were measured according to the method of Example 2. a The test results are shown in Table 4, which helps to determine the stability of the preparation process.

[0050] Table 4. Optimal Process Prediction and Validation Results

[0051] As shown in Table 4, the comprehensive scores (OD values) of the three batches of verification tests were 96.91, 97.64, and 95.67, respectively, with an average of 96.74 and an RSD of 1.01%. The deviation from the model prediction value (91.68) was 5.53%, indicating that the model has good predictive ability and the optimized process has good repeatability.

[0052] Example 5: Correlation between chromaticity parameters and quality indicators

[0053] Raw loquat leaf slices were dried to constant weight in a 60℃ forced-air drying oven, pulverized, and passed through a No. 3 pharmacopoeia sieve. The collected powder was marked as S0 and stored in a sealed, light-protected container for later use. Based on single-factor experiments, the following factors were investigated: soaking time (X1, h), honey-to-water ratio (X2, mass ratio of refined honey to water, 100g / 20g), roasting temperature (X3, ℃), and roasting time (X4, min). The amount of refined honey was fixed. A Box-Behnken design with 4 factors and 3 levels was used. The level codes for each factor and the experimental scheme are shown in Table 5. A total of 29 experimental groups were designed. Refined honey and purified water were mixed in a set ratio, and then loquat leaf powder was added. The mixture was stirred and soaked at room temperature for the specified time. The mixture was then roasted in a roasting machine for the specified time, removed, and allowed to cool naturally to room temperature. After roasting, the sample was dried to constant weight at 60℃, pulverized, passed through a No. 3 pharmacopoeia sieve, and stored in a sealed, light-protected container to obtain roasted loquat leaf powder. Among them, S25-S29 are center point repeat experiments, which are combined to prepare one sample, named S25'.

[0054] A total of 26 samples were collected, including raw loquat leaves (S0) and 25 processed products (S1~S25') using different processing methods. SPSS 27.0 software was used to analyze the color parameters, chemical composition, and DPPH of the 26 samples. The clearance rate was analyzed using Spearman correlation analysis and OPLS-DA analysis. The results are shown in Tables 6 and 7. Figures 3-5 .

[0055] Table 5. Box-Behnken Design Factor Levels and Experimental Scheme for Honey-Fried Loquat Leaves

[0056] Table 6. Results of colorimetric determination of raw loquat leaves and 25 samples of roasted loquat leaves.

[0057] Table 7 Spearman correlation analysis of color parameters, chemical composition, and antioxidant activity of honey-processed loquat leaves.

[0058] As shown in Tables 6 and 7, 5-HMF and L E ab showed a highly significant negative correlation with b It shows a significant negative correlation with a A significant positive correlation was found between DPPH and DPPH. Sweep rate and L b E ab showed a highly significant positive correlation with a There was a highly significant negative correlation between ursolic acid and DPPH. A significant positive correlation was found between chromaticity and 5-HMF, while oleanolic acid showed no significant correlation with any of the indicators. These results indicate that chromaticity parameters are closely related to 5-HMF and antioxidant activity, and can serve as effective indicators for predicting the chemical composition and antioxidant activity of honey-processed loquat leaves.

[0059] Depend on Figures 3-5 It can be seen that OPLS-DA (R 2 X=0.983, R 2 Y=0.674, Q 2 =0.542) in L E ab、b a All VIP values ​​were greater than 1; based on PCA comprehensive evaluation, the optimal processed sample S12 had the highest comprehensive score, while the raw sample S0 had the lowest score. Therefore, it can be seen that honey processing of loquat leaves is of great significance.

[0060] Comparative Example

[0061] Honey-processed loquat leaves were prepared using the method of Example 1, except that (1) the soaking time was adjusted to 0.5h and 1.5h respectively; (2) the honey-water ratio was adjusted to 1:1 and 5:1 respectively; (3) the frying temperature was adjusted to 180℃; and (4) the frying time was adjusted to 30min. The OD value of the honey-processed loquat leaves obtained by each method was determined using the method of Example 2 (the processing method of Example 1 was used simultaneously when preparing the above different processing techniques).

[0062] The results showed that when honey-processed loquat leaves were prepared using the method described in Example 1, the OD value was 80.59 when the soaking time was adjusted only from 1 hour to 0.5 hours, and 77.65 when the soaking time was adjusted only from 1 hour to 1.5 hours, both lower than the OD value of 95.58 when the soaking time was 1 hour. Similarly, the OD value was 45.30 when the honey-to-water ratio was adjusted only from 3:1 to 1:1, and 35.95 when the honey-to-water ratio was adjusted only from 3:1 to 5:1, both lower than the OD value of honey-to-water ratio. When the water ratio is 3:1, the OD value is 95.58. When only the roasting temperature is adjusted from 140℃ to 180℃, the OD value is 33.56, a decrease of 65.9% compared to 98.78 when the roasting temperature is 140℃. This is because the high temperature causes thermal degradation of triterpenoid acid components. When only the roasting time is adjusted from 20 min to 30 min, the OD value is 29.41, a decrease of 69.4% compared to 96.23 when the roasting time is 20 min. Therefore, the optimized process parameters of this invention (1.0 h of soaking, 3:1 honey-water ratio, and 20 min roasting at 140℃) are the best combination to ensure product quality. Any deviation from these parameters leads to a significant decrease in the OD value. Furthermore, the method of this invention can effectively determine whether honey-roasted loquat leaves obtained with different processing parameters are qualified and identify the optimal processing parameters.

[0063] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for evaluating the processing technology of honey-processed loquat leaves based on colorimetric values, characterized in that, Includes the following steps: (1) The CIELab colorimetric value L of honey-processed loquat leaves was determined using a colorimeter. a b Perform detection and calculate E ab; (2) The contents of 5-hydroxymethylfurfural, oleanolic acid and ursolic acid were determined simultaneously by HPLC. (3) The AHP-entropy weighting method is used to calculate the comprehensive score OD value; (4) When the OD value is ≥90 and L Values ​​are 40-60, a When the value is 5-15, the honey-processed loquat leaves prepared under this process are qualified products; The formula for calculating the OD value is: OD = Σ(Wi × normalized content i × 100), Where Wi is the combined weight of the i-th indicator.

2. The method according to claim 1, characterized in that, The colorimeter's testing conditions are: D65 light source, 10° observation angle.

3. The method according to claim 1, characterized in that, The processing method of honey-processed loquat leaves is as follows: after crushing loquat leaf slices, mix them with honey liquid, let them soak for 0.5 to 1.5 hours, stir-fry them at 120 to 160°C for 15 to 25 minutes, cool, dry, and crush them to obtain honey-processed loquat leaves.

4. The method according to claim 3, characterized in that, The honey liquid is prepared by mixing refined honey and water at a mass ratio of 2 to 4:

1.

5. The method according to claim 4, characterized in that, The amount of refined honey used is 15-25g of refined honey per 100g of loquat leaf slices.

6. The method according to claim 3, characterized in that, The processing method for honey-fried loquat leaves also includes measuring the color value (L) of the fried loquat leaves. a The detection, when L Values ​​are 40-60 and a When the value is 5~15, cooling, drying, and pulverizing processes are performed; when L Value and a The value does not conform to L Values ​​are 40-60, a When the value is 5 to 15, continue with the soaking and stir-frying process.

7. The method according to claim 1, characterized in that, The E The formula for calculating ab is: E ab = (L) 2 +a 2 +b 2 )^(1 / 2).

8. The method according to claim 1, characterized in that, The detection conditions for the HPLC method are as follows: a C18 column is used, the mobile phase is acetonitrile-0.1% phosphoric acid water gradient elution, the flow rate is 0.6 mL / min, and the detection wavelength is 300 nm for 5-hydroxymethylfurfural, and the detection wavelength is 210 nm for oleanolic acid and ursolic acid.

9. The method according to claim 1, characterized in that, The combined weight of oleanolic acid and ursolic acid was 0.7675, and the combined weight of 5-hydroxymethylfurfural was 0.2325.

10. The method according to claim 1, characterized in that, The formula for calculating Wi is: Wi = (Wai × Wei) / Σ(Wai × Wei); Where Wai is the AHP weight and Wei is the entropy weight.

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