Quality evaluation method of rhizoma polygonati processed product

Abstract

The invention provides a quality evaluation method of a rhizoma polygonati processed product, and belongs to the technical field of medicinal material processing. According to the method, volatile components, polysaccharides, total flavonoids, total polyphenols or antioxidant activity of the rhizoma polygonati processed product are detected and are used as evaluation indexes to construct a comprehensive scoring model so as to evaluate the quality of the rhizoma polygonati processed product. According to the method, the optimal processing condition can be rapidly screened out, the application process of rhizoma polygonati in the large health industry is accelerated, and high-quality development of the rhizoma polygonati industry is promoted.

Description

Technical Field

[0001] The present invention belongs to the technical field of medicinal material processing, and specifically relates to a quality evaluation method for processed products of Polygonati Rhizoma, and its application in the processing effect of Polygonatum cyrtonema Hua. Background Art

[0002] According to the Pharmacopoeia of the People's Republic of China (2020 Edition), Polygonati Rhizoma includes three original sources: Polygonatum sibiricum Red., Polygonatum kingianum Coll. et Hemsl., and Polygonatum cyrtonema Hua. Polygonatum cyrtonema Hua is one of the three original medicinal materials of Polygonati Rhizoma, and its main active ingredients include polysaccharides, steroidal saponins, flavonoids, and polyphenols, etc., with effects such as anti-fatigue, improving intestinal flora, antidepressant, and enhancing immunity. According to the data provided by the National Innovation Alliance of the Polygonati Rhizoma Industry, the comprehensive output value of Polygonati Rhizoma exceeded 20 billion yuan in 2024, including newly added planting area of about 200,000 mu, more than 1 billion seedlings, and output value of about 1 billion yuan. As the authentic medicinal material with the largest planting area in Fujian Province, Polygonatum cyrtonema Hua has been included in the "Nine Flavors of Fujian" Chinese medicinal material industry cluster project of the Ministry of Agriculture and Rural Affairs in 2023, and its industrial development has broad prospects. The rhizome of Polygonatum cyrtonema Hua is rich in carbohydrates (65 - 90%), protein (6.7 - 11.6%), saponins (2.73 - 5.01%), etc., and was included in the List of Substances that are Both Food and Medicine of the State (No. 51, 2002, issued by the Ministry of Health and Family Planning Commission of the People's Republic of China) in 2002, with a history of food and medicine use for more than 2,000 years.

[0003] However, the raw rhizome of Polygonatum cyrtonema Hua tastes numb and pricks the throat. Although it is non-toxic, it is not suitable for direct medicinal use. To reduce irritation and enhance efficacy, traditional processes make it black, soft, and sweet through steaming and drying, such as the nine-steaming and nine-drying method, the heavy-steaming method, the Meng Shen method, the wine-making method, and the co-steaming method with black beans. Currently, there is a rich variety of Polygonatum cyrtonema Hua products on the market, covering Huangjing decoction pieces, wine-processed Huangjing, Huangjing sesame pills, Huangjing wine, and Huangjing tea, etc. Among them, the "nine-steaming and nine-sunning" Polygonatum cyrtonema Hua tea dominates the market. These processing methods significantly affect the chemical composition transformation and biological activities of Polygonatum cyrtonema Hua. For example, steaming and drying can cause the degradation of Polygonatum cyrtonema Hua fructan to produce about 38% fructose and induce the Maillard reaction. The Maillard reaction is a series of non-enzymatic reactions between the free amino acid groups of proteins (such as lysine and arginine) and the carbonyl groups of reducing sugars (such as fructose and glucose), and it is the most important flavor source in thermally processed foods. Existing research reports have shown that the "six-steaming and six-making" Huangjing is the ideal end point for Huangjing processing; Ma Jiali et al. explored the variation law of components during the processing of Polygonatum cyrtonema Hua. However, currently, the changes in the chemical composition of Polygonatum cyrtonema Hua before and after processing and its mechanism of action on the nutrition and efficacy of products are not clear. In the field of Huangjing processing and application, how to maximize its efficacy and quickly and accurately evaluate the processing effect is the current key problem. Constructing a scientific and effective evaluation model is particularly important. By establishing a precise model, various factors affecting its efficacy during the processing of Huangjing can be systematically analyzed, thus providing a clear direction and basis for optimizing the processing technology. At the same time, the model can quickly screen out the best processing conditions, laying a solid foundation for the development of new functional foods. This not only helps to improve the quality and stability of Huangjing products but also accelerates their application process in the big health industry and promotes the high-quality development of the Huangjing industry. Therefore, constructing a scientific evaluation model is the core key to solving the problems of Huangjing processing and application and has important practical significance. Summary of the Invention

[0004] To solve the problem of evaluating the processing effect of Huangjing, the present invention provides a method for evaluating the quality of processed Huangjing to quickly evaluate whether the quality of the processed Huangjing meets the requirements.

[0005] To achieve the above object, the inventor provides the following technical solutions:

[0006] A method for evaluating the quality of processed Huangjing, the evaluation method comprising the following steps:

[0007] First step, detecting the volatile components in the processed Huangjing by headspace solid-phase microextraction-gas chromatography-mass spectrometry; the volatile components include esters, alkanes, ketones, acids, and aromatic compounds;

[0008] Second step, detecting the polysaccharides, total flavonoids, total polyphenols, and antioxidant activities in the processed Huangjing; the antioxidant activities include DPPH scavenging activity and ABTS+ Free radical scavenging activity;

[0009] In the third step, select more than three of volatile components, polysaccharides, total flavonoids, total polyphenols or antioxidant activities as evaluation indicators;

[0010] In the fourth step, standardize the detection data of each indicator to make the indicators with different dimensions comparable. For the indicators with the rule of "the higher the better", use Min-Max normalization to convert the value of each indicator to the range of 0 to 1; for the indicators with the rule of "the lower the better", reverse their normalized values so that the lower value corresponds to a higher score;

[0011] In the fifth step, calculate the standard deviation of each indicator to measure the information content or resolution ability of the indicator;

[0012] In the sixth step, calculate the correlation and comprehensive information content between the indicators;

[0013] In the seventh step, calculate the objective weight of each indicator through normalization, and then use these weights to conduct a comprehensive score for each sample;

[0014] In the eighth step, if the comprehensive score reaches above 0.8, the processing of Polygonatum sibiricum Red. reaches the ideal end point, that is, the quality of the processed Polygonatum sibiricum Red. meets the requirements.

[0015] Furthermore, the detection method of the volatile components described in the second step is as follows:

[0016] Sample pretreatment: Accurately weigh the Polygonatum sibiricum Red. powder into a headspace vial, and extract the headspace with a 100μm / PDMS fiber extraction head at 65 - 75°C in a water bath for 15 - 25 minutes, then desorb it in the injection port at 240 - 260°C for 2 - 4 minutes for GC-MS analysis; before using the extraction head, first activate it in the gas chromatograph of the injection port at 240 - 260°C for 25 - 35 minutes;

[0017] Chromatographic conditions: Injection port temperature 240 - 260°C; Manual injection 1 - 2 μL; Programmed temperature rise: Initial temperature 45 - 55°C, hold for 2 - 3 minutes, rise to 200 - 220°C at 7 - 9°C / min, rise to 270 - 290°C at 15 - 25°C / min, hold for 2 - 3 minutes; Flow rate 1.0 - 1.5 mL / min;

[0018] Mass spectrometry conditions: Carrier gas is high-purity helium; Flow rate 1.0 - 1.5 mL / min; Injection volume 1.0 - 2.0 μL; Transfer line temperature 240 - 260°C; Ion source is EI source; Ion source temperature 220 - 240°C; Electron energy is 70 eV, quadrupole temperature is 140 - 160°C; Scanning range m / z: 35 - 450;

[0019] Spectrum retrieval: NIST05 spectral library.

[0020] Furthermore, the better-the-better indexes described in the fourth step include 1-(1H-pyrrol-2-yl)-ethanone, cyclohexasiloxane, tetradecane, hexadecane, tetradecamethyl-cycloheptasiloxane, DPPH scavenging activity, ABTS + radical scavenging activity, polysaccharides, total flavonoids and total polyphenols.

[0021] Furthermore, the evaluation method also includes measuring the color of the processed polygonatum using a color difference meter, and establishing a regression equation using the comprehensive score and hue; obtaining the comprehensive score by detecting the hue of the sample to be evaluated, so as to evaluate the quality of the processed polygonatum.

[0022] Furthermore, the application of the quality evaluation method of the processed polygonatum in the evaluation of the processing effect of Polygonatum cyrtonema Hua.

[0023] Furthermore, the application method is to establish a regression equation using the comprehensive score and hue as Y = 0.97 - 0.08*h, where Y is the comprehensive score and h is the hue; obtaining the comprehensive score by detecting the hue of the processed Polygonatum cyrtonema Hua to be evaluated; if the comprehensive score reaches above 0.8, the quality of the processed Polygonatum cyrtonema Hua meets the requirements.

[0024] The beneficial effects of the present invention are:

[0025] (1) By constructing a scientific evaluation model, the quality of the processed polygonatum can be evaluated quickly and accurately. In particular, it is possible to quickly judge whether the processing of polygonatum reaches the ideal end point only based on the color change, greatly improving the evaluation efficiency.

[0026] (2) Provide a scientific basis for optimizing the processing technology: By systematically analyzing the changes in chemical components and biological activities during the processing of polygonatum, it is clear that "seven steaming and seven processing" is the ideal end point of polygonatum processing. This provides a clear direction and scientific basis for optimizing the processing technology of polygonatum, and helps to improve the quality and stability of polygonatum products.

[0027] (3) Promote the high-quality development of the polygonatum industry: The present invention not only provides a standardized method for evaluating the processing effect of polygonatum, but also lays a foundation for the development of new functional foods. Through the accurate evaluation model, the best processing conditions can be quickly screened out, accelerating the application process of polygonatum in the large health industry and promoting the high-quality development of the polygonatum industry. Description of the Drawings

[0028] Figure 1 It is the appearance diagram of Polygonatum cyrtonema Hua with different steaming times described in the specific implementation manner.

[0029] Figure 2 It is the total ion current chromatogram of the volatile components of "seven steaming and seven processing" Polygonatum cyrtonema Hua described in the specific implementation manner.

[0030] Figure 3 The polysaccharide content (a), total flavonoid content (b), total polyphenol content (c), and antioxidant activity (d) of the nine-steamed and nine-boiled Polygonatum cyrtonema Hua described in the specific implementation manner (P < 0.05).

[0031] Figure 4 The dynamic change mechanism of the chemical composition, antioxidant activity, and volatile flavor of the nine-steamed and nine-boiled Polygonatum cyrtonema Hua described in the specific implementation manner. Specific implementation manner

[0032] To elaborate in detail on the technical content, achieved objectives, and effects of the technical solution, the following will be described in detail with reference to specific examples and in conjunction with the accompanying drawings.

[0033] Example 1

[0034] 1 Materials and reagents

[0035] Anthrone (analytical pure) was purchased from Sinopharm Chemical Reagent Co., Ltd.; concentrated sulfuric acid (analytical pure, 95.5%), absolute ethanol (analytical pure), and sodium hydroxide (NaOH, analytical pure) were purchased from Xilong Scientific Co., Ltd.; glucose (standard product) was purchased from Tianjin Ruijinte Chemical Co., Ltd.; 1,1-diphenyl-2-picrylhydrazyl (DPPH, analytical pure) was purchased from Hefei BASF Biotechnology Co., Ltd.; 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS, analytical pure) was purchased from Hefei BASF Biotechnology Co., Ltd. Sodium nitrite (NaNO2, analytical pure) was purchased from Tianjin Bodi Chemical Co., Ltd.; aluminum nitrate (Al(NO3)3, analytical pure) was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.; gallic acid (99%) and rutin (standard product) were purchased from Shanghai Macklin Biochemical Co., Ltd.; Folin-Ciocalteu reagent (BR) was purchased from Yuanye Bio-Technology Co., Ltd.; anhydrous sodium carbonate solution (analytical pure) was purchased from Guangzhou Jinhua University Chemical Reagent Co., Ltd. The rhizomes of Polygonatum cyrtonema Hua (collected from the Wuyishan base on February 13, 2023).

[0036] 2 Methods and results

[0037] 2.1 Processing of the nine-steamed and nine-boiled Polygonatum cyrtonema Hua

[0038] Polygonatum cyrtonema Hua was processed by steaming, drying, etc. according to the nine-steamed and nine-boiled process. Healthy rhizomes were selected, sun-dried to 70-80% dryness, washed, the epidermis and rootlets of the rhizomes were removed, steamed in a steamer for 85 min, and dried at 60 °C to obtain the Polygonatum cyrtonema Hua steamed once. After repeating the process nine times, the 1-9 times steamed Polygonatum cyrtonema Hua was obtained, sliced and ground, and reserved as samples of Polygonatum cyrtonema Hua with different steaming times, named C0, C1, C2, C3, C4, C5, C6, C7, C8, and C9, respectively.

[0039] The color changes of Polygonatum cyrtonema Hua with different steaming times were determined by a color difference meter as follows Figure 1 As shown, the results indicate that with the increase in the number of steaming times, the color of Polygonatum cyrtonema Hua gradually deepens, the brightness (L* value) significantly decreases, from the initial 4.80 ± 0.09 to 0.44 ± 0.07 (9 times of steaming), and the red tone (a* value), yellow tone (b* value), saturation (c* value) and hue (h) also show a decreasing trend. In addition, the color difference (△E value) increases significantly with the increase in the number of steaming times, indicating that the color change becomes more obvious.

[0040] Table 1 Chromaticity changes of Polygonatum cyrtonema Hua with different steaming times

[0041]

[0042] 2.2 HS-SPME-GC-MS analysis of Polygonatum cyrtonema Hua processed by nine-steaming and nine-boiling

[0043] The volatile flavors of the samples were analyzed by headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). Sample pretreatment: Accurately weigh 1.0 g of Polygonatum cyrtonema Hua powder with different steaming times into a 50 mL headspace vial. After extracting the headspace with a 100 μm / PDMS fiber extraction head at 70 °C in a water bath for 20 min, desorb it in the injection port at 250 °C for 3 min for GC-MS analysis. Before using the extraction head, first activate it in the gas chromatography of the injection port at 250 °C for half an hour. Chromatographic conditions: Injection port temperature 250 °C; Manual injection 1 μL; Programmed temperature rise: Initial temperature 50 °C, hold for 2 min, rise to 200 °C at 8 °C / min, rise to 280 °C at 20 °C / min, hold for 2 min; Flow rate 1.0 mL / min. Mass spectrometry conditions: Carrier gas is high-purity helium; Flow rate 1.0 mL / min; Injection volume 1.0 μL. Transfer line temperature 250 °C; Ion source is EI source; Ion source temperature 230 °C; Electron energy is 70 eV quadrupole, temperature is 150 °C; Scanning range m / z: 35 - 450. Spectral retrieval: NIST05 spectral library.

[0044] The types and contents of volatile characteristic flavor components in Polygonatum cyrtonema Hua processed by nine-steaming and nine-boiling were determined by HS-SPME-GC-MS. The total ion chromatogram of Polygonatum cyrtonema Hua processed by "seven-steaming and seven-boiling" is as follows Figure 2As shown. Through GC-MS analysis, 50 volatile compounds were detected in the multi-steamed and multi-boiled Polygonatum cyrtonema Hua, among which 39 had a matching degree of ≥80%, as shown in Table 2. They mainly included five categories: esters, alkanes, ketones, acids, and aromatic compounds. Among them, alkanes (C8-C16) and aromatic compounds accounted for 62.3±3.8% of the total volatile components, constituting the main characteristic flavor of Polygonatum cyrtonema Hua. Changes in alkane compounds: The content of octamethyl-cyclotetrasiloxane decreased from 2.53%±1.46% in the initial preparation to not detected (ND) in the final preparation, indicating that low-molecular-weight alkanes (such as those below C8) are more volatile under thermal action, which conforms to the pyrolysis law controlled by Gibbs free energy (ΔG = ΔH - TΔS). While dodecamethyl-cyclohexasiloxane stabilized from 5.54%±3.85% to 4.80%±3.63% (P>0.05), indicating that high-molecular-weight alkanes are relatively stable and not easily affected by the number of steaming times. Changes in ketone compounds: 3-Methyl-1,2-cyclopentanedione decayed exponentially with the number of steaming times, indicating that it gradually volatilized or degraded during multiple steaming processes. 1-(1H-Pyrrol-2-yl)-ethanone accumulated significantly to 9.14%±2.79% (P<0.01), which is consistent with the formation kinetics of α-amino ketones in the Strecker degradation pathway, indicating a competitive formation mechanism of Maillard reaction intermediates. Acids and aldehydes compounds: Caprylic acid is a short-chain fatty acid with a pungent odor and completely volatilized after nine steamings, which may be one of the key mechanisms for "detoxification". Benzeneacetaldehyde is a common aldehyde compound with fruity and floral scents and completely volatilized after nine steamings, indicating its strong volatility. The volatilization of these short-chain molecules makes the flavor of Polygonatum cyrtonema Hua softer and sweeter, meeting the goal of "nine steamings and nine sunnings" in traditional processes. Aromatic compounds: 2,4,6-Tri-tert-butylphenol with three tert-butyl substituents on the benzene ring decreased significantly (1.91%→ND), while 2,4-Di-tert-butylphenol with two tert-butyl substituents on the benzene ring was relatively stable (from 1.09% to 1.29%), indicating that the steric hindrance effect of substituents affects thermal stability. The reduction of 2,4,6-tri-tert-butylphenol may lead to a softer flavor of Polygonatum cyrtonema Hua. The relative stability of 2,4-di-tert-butylphenol may help maintain certain flavor characteristics of Polygonatum cyrtonema Hua. This compound has antioxidant properties, and its relative stability in content may play a certain role in protecting the flavor and quality of Polygonatum cyrtonema Hua. It reveals the significant influence of chemical structure on thermal stability and chemical reactions. This difference not only affects the flavor and quality of Polygonatum cyrtonema Hua but also provides an important reference for optimizing the processing technology.

[0045] Table 2 Volatile chemical components of multi-steamed and multi-boiled Polygonatum cyrtonema Hua

[0046]

[0047]

[0048]

[0049]

[0050] 2.3 Determination of the Contents of Polysaccharides, Total Flavonoids, and Total Polyphenols in Nine-Steamed and Nine-Boiled Polygonatum cyrtonema Hua and Determination of Its Antioxidant Activity

[0051] Determination of polysaccharide content: The extraction of Polygonatum cyrtonema Hua polysaccharide was carried out under the optimized conditions with a liquid-to-material ratio of 41 mL / g, an ultrasonic time of 40 min, an ultrasonic power of 151 W, and an ultrasonic temperature of 59 °C. The polysaccharide content was determined by the anthrone-sulfuric acid method. Determination of total flavonoid and total polyphenol contents: Specifically, the NaNO2-Al(NO3)3 colorimetric method was used to determine the total flavonoid content; the Folin-Ciocalteu colorimetric method was used to determine the total polyphenol content. The water-soluble substances of Polygonatum cyrtonema Hua with different steaming times were extracted, freeze-dried, and formulated into 15 mg / mL for the determination of antioxidant activity, including DPPH scavenging activity and ABTS + radical scavenging activity. The specific method was referred to the literature (Zheng Meixia, Su Hailan, Li Chiqin, et al. Optimization of ultrasonic extraction process of Polygonatum cyrtonema Hua polysaccharide by response surface methodology and its biological activity research [J]. China Food Additives, 2024, (9): 1-9.).

[0052] The contents of polysaccharides, total flavonoids, total polyphenols, and antioxidant properties of Polygonatum cyrtonema Hua with different steaming times are as Figure 3 shown. The results showed that with the increase in the number of steaming times, significant changes occurred in the chemical composition and biological activity of Polygonatum cyrtonema Hua. With the increase in the number of processing times, the polysaccharide content decreased, while the total flavonoid and total polyphenol contents increased significantly. When not steamed, the total flavonoid content was 0.6527 ± 0.0002 mg / g, and the total polyphenol content was 0.7481 ± 0.0028 mg / g; after 9 times of steaming, the total flavonoid content increased to 3.8677 ± 0.0069 mg / g, and the total polyphenol content increased to 4.1713 ± 0.0038 mg / g, increasing by nearly 6 times respectively. Bioactive substances such as total flavonoids and total polyphenols are more sensitive to high-temperature treatment, and this processing technology can better retain these thermosensitive bioactive substances. The antioxidant experiment further confirmed the significant effect of the steaming times on the biological activity of Polygonatum cyrtonema Hua. When not steamed, the DPPH scavenging activity was 20.97 ± 0.95%, and the ABTS + scavenging activity was 36.28 ± 1.86%; after 9 times of steaming, the DPPH scavenging activity increased to 69.66 ± 0.42%, and the ABTS+ scavenging activity increased to 96.58 ± 0.18%, increasing by about 3 times and 2.7 times respectively. Steaming 7 times or more can significantly improve the antioxidant ability of Polygonatum cyrtonema Hua.

[0053] 2.4 Establishment of a Scoring Model by the Critic Objective Weight Assignment Method

[0054] Dynamic change mechanism of chemical components, antioxidant properties and volatile flavor of Polygonatum cyrtonema Hua steamed and processed nine times is as follows Figure 4 shown. During the nine-steaming and nine-boiling process of Polygonatum cyrtonema Hua, Maillard reaction, Strecker degradation and steric hindrance effect of substituents occurred, and the ideal end point was reached after "seven-steaming and seven-boiling". In order to better judge its quality by color, a scoring model was established using the CRITIC (Criteria Importance Through Intercriteria Correlation) method. The steps are as follows:

[0055] (1) Select 39 volatile chemical components (Table 2), polysaccharides, total flavonoids, total polyphenols, and 2 antioxidant activities (DPPH, ABTS + ) as the quality indicators of processed products of Polygonatum cyrtonema Hua;

[0056] (2) Use Min-Max normalization to make indicators with different dimensions comparable: for indicators with "the higher the better", convert the normalized value f of each indicator to the range of 0 to 1; for indicators with "the lower the better", reverse their normalized values, that is, 1 - f, so that lower values correspond to higher scores; the normalized value is applicable to the following formula (a):

[0057] f = (x ij - min(x j )) / (max(x j ) - min(x j )) (a)

[0058] In the formula, f is the normalized value, x ij is the measured value of indicator j of sample i, and x j is the value of indicator j in all samples.

[0059] Among them, the indicators with "the higher the better" include 1-(1H-pyrrol-2-yl)-ethanone, cyclohexasiloxane, tetradecane, hexadecane, tetradecamethyl-cycloheptasiloxane, DPPH scavenging activity, ABTS + radical scavenging activity, polysaccharides, total flavonoids and total polyphenols.

[0060] Calculate the standard deviation s of each normalized indicator, which is used to measure the information content (discrimination ability) of the indicator. The following formula (b) is applicable:

[0061]

[0062] In the formula, s is the sample standard deviation, x i is the measured value of sample i, is the mean value of this indicator in all samples, and n is the sample size.

[0063] (3) Calculate the correlation r and the comprehensive information quantity Cj between the indicators, and apply the following formulas (c), (d):

[0064]

[0065] In the formula, r is the correlation coefficient (the value range is [-1, 1]); x i , y i —— are the measured values of the indicators x and y in the sample i; —— are the mean values of the indicators x and y respectively.

[0066]

[0067] In the formula, Cj is the information quantity of the indicator j, and σ j is the standard deviation of the indicator j, and r jk is the correlation coefficient between the indicator j and the indicator k.

[0068] (4) Calculate the objective weight wj of each component through normalization, and then use these weights to conduct a comprehensive score for each sample. Apply the following formulas (e), (f):

[0069] wj = Cj / ∑(Cj) (e)

[0070] In the formula, wj is the normalized weight, and Cj is the information quantity of each indicator.

[0071]

[0072] In the formula, Y i is the comprehensive score of the i-th sample, Xij is the normalized value of the i-th sample on the j-th indicator, and wj is the weight of the j-th indicator.

[0073] The indicators with higher weights and the higher the better are polysaccharides, total flavonoids and total polyphenols, and the indicators with higher weights and the lower the better are 4H-pyran-4-one, 2-ethylhexyl salicylate and 4-chlorobenzenesulfonamide. The comprehensive scores Y of the nine-steamed and nine-boiled Polygonatum cyrtonema Hua are 0.613, 0.665, 0.639, 0.659, 0.683, 0.660, 0.859, 0.834 and 0.919 in sequence. The ideal end point of the processing of Polygonatum cyrtonema Hua is that the comprehensive score is above 0.8, that is, the quality of the Polygonatum cyrtonema Hua processed by "seven-steamed and seven-boiled" meets the requirements.

[0074] Analyze whether there is a correlation between the comprehensive score and the yellow tone b*, red tone a*, hue h, brightness L* and saturation c*, and the Pearson analysis method shows that the comprehensive score Y is significantly correlated with the yellow tone b* (R 2= -0.734, P = 0.024); It was also significantly correlated with brightness L* (R 2 = -0.786, P = 0.012); There was no obvious correlation with red tone a* (R 2 = -0.658, P = 0.055); It was significantly correlated with saturation c* (R 2 = -0.785, P = 0.012); It was significantly correlated with hue h (R 2 = -0.773, P = 0.015). Using stepwise regression, the optimal model was established by stepwise selection of variables. The regression equation between the comprehensive score Y and hue h was Y = 0.97 - 0.08*h, and the model had statistical significance (R 2 = 0.785, P = 0.012). That is, the quality of processed polygonatum rhizome can also be rapidly evaluated through color changes.

[0075] In summary, the quality of processed polygonatum cyrtonema hua can be accurately evaluated by a scoring model constructed with multiple indexes such as volatile chemical components, polysaccharides, total flavonoids, total polyphenols, antioxidant activities, etc. Similarly, the quality of processed polygonatum cyrtonema hua can also be rapidly evaluated through the hue of the processed product. Both evaluation models have clarified that "steaming and processing seven times" is the ideal end point for processing polygonatum cyrtonema hua.

[0076] It should be noted that although the above-mentioned embodiments have been described in this article, the patent protection scope of the present invention is not limited thereby. Therefore, based on the innovative concept of the present invention, any changes and modifications made to the embodiments described in this article, or equivalent structural or equivalent process transformations made by using the content of the specification and drawings of the present invention, and directly or indirectly applying the above technical solutions to other related technical fields, are all included in the patent protection scope of the present invention.

Claims

1. A quality evaluation method for processed Polygonatum sibiricum Red., characterized in that, The evaluation method described above includes the following steps: In the first step, headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) is used to detect the volatile components in the processed polygonatum rhizome. The volatile components include esters, alkanes, ketones, acids, and aromatic compounds. Step 2, detecting polysaccharides, total flavonoids, total polyphenols and antioxidant activities in the processed polygonatum sibiricum; the antioxidant activities include DPPH scavenging activity and ABTS + radical scavenging activity; In the third step, more than three of the volatile components, polysaccharides, total flavonoids, total polyphenols, or antioxidant activities are selected as evaluation indicators. In the fourth step, the detection data of each indicator are standardized to make the indicators with different dimensions comparable. For the indicators with the rule of "the higher the better", the Min-Max normalization is used to convert the value of each indicator to the range of 0 to 1. For the indicators with the rule of "the lower the better", their standardized values are inverted so that the lower values correspond to higher scores. In the fifth step, the standard deviation of each indicator is calculated to measure the information content or resolution ability of the indicator. In the sixth step, the correlation and comprehensive information content between the indicators are calculated. In the seventh step, the objective weight of each indicator is calculated through normalization, and then these weights are used to comprehensively score each sample. In the eighth step, if the comprehensive score reaches 0.8 or above, the processing of polygonatum rhizome reaches the ideal end point, that is, the quality of the processed polygonatum rhizome meets the requirements.

2. The quality evaluation method of the processed Polygonatum sibiricum Red. product according to claim 1, characterized in that, The detection method of the volatile components described above is as follows: Sample pretreatment: Accurately weigh the polygonatum rhizome powder into a headspace vial. After extracting the headspace with a 100μm / PDMS fiber extraction head at 65 - 75°C in a water bath for 15 - 25 minutes, desorb it in the injection port at 240 - 260°C for 2 - 4 minutes for GC-MS analysis. Before using the extraction head, first activate it in the gas chromatography of the injection port at 240 - 260°C for 25 - 35 minutes. Chromatographic conditions: Injection port temperature 240 - 260°C; Manual injection 1 - 2 μL; Programmed temperature rise: Initial temperature 45 - 55°C, hold for 2 - 3 minutes, rise to 200 - 220°C at 7 - 9°C / min, rise to 270 - 290°C at 15 - 25°C / min, hold for 2 - 3 minutes; Flow rate 1.0 - 1.5 mL / min. Mass spectrometry conditions: Carrier gas is high-purity helium gas; Flow rate 1.0 - 1.5 mL / min; Injection volume 1.0 - 2.0 μL; Transfer line temperature 240 - 260°C; Ion source is EI source; Ion source temperature 220 - 240°C; Electron energy is 70 eV, quadrupole temperature is 140 - 160°C; Scanning range m / z: 35~450. Spectrum retrieval: NIST05 spectral library.

3. The quality evaluation method of the processed polygonatum sibiricum redouté product according to claim 1, wherein, The indicators that the higher the better described in the fourth step include 1-(1H-pyrrol-2-yl)-ethanone, cyclohexasiloxane, tetradecane, hexadecane, tetradecamethyl-cycloheptasiloxane, DPPH radical scavenging activity, ABTS + radical scavenging activity, polysaccharide, total flavonoid and total polyphenol.

4. The quality evaluation method of the processed polygonatum sibiricum redoute according to any one of claims 1-3, characterized in that The evaluation method also includes using a colorimeter to measure the color of the processed polygonatum rhizome, and establishing a regression equation between the comprehensive score and the hue. The quality of the processed polygonatum rhizome is evaluated by obtaining the comprehensive score through detecting the hue of the sample to be evaluated.

5. Application of the quality evaluation method of the processed polygonatum rhizome as described in any one of claims 1 - 4 in the evaluation of the processing effect of polygonatum cyrtonema.

6. Use of the method for evaluating the quality of the processed product of Polygonatum sibiricum Red. in evaluating the processing effect of Polygonatum cyrtonema Hua., characterized in that, The application method is that the regression equation established between the comprehensive score and the hue is Y = 0.97 - 0.08*h, where Y is the comprehensive score and h is the hue. The comprehensive score is obtained by detecting the hue of the processed polygonatum cyrtonema sample to be evaluated. If the comprehensive score reaches 0.8 or above, the quality of the processed polygonatum cyrtonema meets the requirements.

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