Sichuan pepper flavor quality comprehensive evaluation method based on flavor omics and principal component analysis

Abstract

The invention relates to the technical field of food analysis, in particular to a pepper flavor quality comprehensive evaluation method based on flavor omics and principal component analysis, which comprises the following steps: (1) measuring flavor quality evaluation indexes of different types of peppers; (2) analyzing the measured flavor quality evaluation index result based on a flavor omics technology, and screening main contribution indexes of pepper quality difference; (3) comprehensively scoring the main contribution indexes of the flavor quality of the Chinese prickly ash by adopting a principal component analysis method; and (4) based on a comprehensive scoring result, screening pepper categories with high flavor. The related quality indexes of the pepper flavor are analyzed and detected by an instrument, and compared with a traditional sensory evaluation method, the whole flavor quality of the pepper is evaluated more objectively and accurately based on the combination of a flavor omics technology and a principal component analysis method.

Description

Technical Field

[0001] The present invention relates to the technical field of food analysis, and in particular to a comprehensive evaluation method for Zanthoxylum bungeanum flavor quality based on flavoromics and principal component analysis. Background Art

[0002] Sichuan peppercorns can be divided into two categories based on the color of their skin: green and red. Due to the high yield of green peppercorns in southwest my country, and the constraints of a short harvest period and low efficiency of manual harvesting, some green peppercorns are not harvested in time. As green peppercorns continue to grow after the harvest period, their skin will gradually turn reddish-brown. In the industry, these peppercorns that turn red are called red-turned peppercorns (also known as red-turned peppers). Red-turned peppercorns belong to the green pepper category and refer to peppercorns whose skin color has turned reddish-brown due to failure to harvest them in time. They are mainly grown in Yunnan and Sichuan provinces in my country. Current research on peppercorn quality focuses on the quality differences between red and green peppercorns. Research on the flavor quality characteristics of red-turned peppercorns will help improve the quality and efficiency of my country's peppercorn industry.

[0003] Currently, the dominant varieties of Sichuan peppercorns in my country include Gansu red peppercorns, Sichuan Hanyuan tribute peppercorns, Shaanxi Hancheng red peppercorns, Maowen red peppercorns, Nanlu peppercorns, Yunnan green peppercorns, Sichuan green peppercorns, and Sichuan vine peppercorns. Due to factors such as the production environment, the flavor quality of Sichuan peppercorns varies across different production areas and varieties. For example, Gansu Wudu peppercorns have a strong, numbing effect, like a strong liquor, while Sichuan Hanyuan peppercorns have a lingering, fragrant, and numb taste like tea. A comprehensive analysis of the flavor quality of Sichuan peppercorns can more efficiently and accurately rank them. Currently, the overall flavor quality of Sichuan peppercorns relies primarily on sensory evaluation, which is highly subjective. Summary of the Invention

[0004] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a comprehensive evaluation method for Zanthoxylum bungeanum flavor quality based on flavoromics and principal component analysis.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0006] A method for comprehensively evaluating the flavor quality of Zanthoxylum bungeanum based on flavoromics and principal component analysis is provided, which comprises the following steps:

[0007] (1) Determine the flavor quality evaluation indexes of different types of Zanthoxylum bungeanum;

[0008] (2) Analyze the flavor quality evaluation index results measured above based on flavoromics technology to screen the main contributing indicators to the quality differences of Zanthoxylum bungeanum;

[0009] (3) The principal component analysis method was used to comprehensively score the main contributing indicators of Zanthoxylum bungeanum flavor quality;

[0010] (4) Based on the comprehensive scoring results, select the pepper categories with high flavor.

[0011] Furthermore, in step (1), the categories of Sichuan pepper include green Sichuan pepper, red green Sichuan pepper and red Sichuan pepper; wherein, red green Sichuan pepper refers to Sichuan pepper whose skin color has changed from green Sichuan pepper to slightly reddish brown after it is not harvested in time.

[0012] Furthermore, in step (1), the evaluation index of Zanthoxylum bungeanum flavor quality includes total numbing factor, hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, hydroxy-ε-sanshool, volatile oil, α-pinene, levorotatory-α-pinene, sabinene, β-pinene, myrcene, β-phellandrene, D-limonene, eucalyptol, ocimene, γ-terpinene, linalool oxide, terpinolene, linalool, 4-terpineol, terpineol, nerol, linalyl acetate, terpineyl acetate, neryl acetate, geranyl acetate, and β-caryophyllene.

[0013] Furthermore, in step (1), the flavoromics technology includes one-way analysis of variance, two-way analysis of variance, correlation analysis, multiple unpaired t-test and cluster analysis.

[0014] Furthermore, in step (2), the main contributing indicators to the quality difference of Zanthoxylum bungeanum include total linalool, hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, hydroxy-ε-sanshool, volatile oil, β-phellandrene, β-pinene, γ-terpinene, sabinene, linalool, D-limonene and myrcene.

[0015] Furthermore, in step (3), the comprehensive score calculation expression in the principal component analysis method is: Y = 0.50027y1 + 0.34256y2 + 0.05230y3, and the Y value is positively correlated with the flavor quality of Sichuan pepper;

[0016] The calculation formulas for y1, y2, and y3 are as follows:

[0017] y1=-0.298x 23 -0.285x 21 -0.282x 25 +0.270x 10 +0.266x8+0.265x9+0.264x 19 +0.254x6-0.247x 26 -0.247x 27 +0.232x 17 -0.227x 20 +0.202x3-0.157x 22 +0.039x 16 +0.055x7+0.098x 12 +0.025x18 -0.188x 14 -0.190x 24 +0.154x5;

[0018] y2=0.064x 23 +0.105x 21 +0.146x 25 +0.159x 10 +0.158x8+0.171x9+0.114x 19 +0.049x6+0.216x 26 +0.216x 27 +0.142x 17 +0.248x 20 +0.152x3-0.182x 22 +0.361x 16 +0.357x7+0.339x12+0.303x 18 +0.280x 14 +0.280x 24 +0.125x5;

[0019] y3=0.085x 23 +0.031x 21 +0.039×x 25 -0.091x 10 -0.138x8-0.161x9-0.073x 19 -0.156x6-0.037x 26 -0.037x 27 -0.080x 17 -0.048x 20 +0.510x3+0.225x 22 -0.040x 16 -0.130x7-0.016x 12 +0.283x 18 -0.074x 14 -0.053x 24 +0.691x5;

[0020] x3、x 5～ x 10 、x 12 、x 14 、x 16～ x 27The data after standardization are hydroxy-β-sanshool, hydroxy-ε-sanshool, volatile oil, α-pinene, levorotatory-α-pinene, sabinene, β-pinene, β-phellandrene, eucalyptol, γ-terpinene, linalool oxide, terpinolene, linalool, 4-terpineol, terpineol, nerol, linalyl acetate, terpineyl acetate, neryl acetate, geranyl acetate, and β-caryophyllene.

[0021] The beneficial effects of the present invention are:

[0022] The present invention provides a method for comprehensively evaluating the flavor quality of Sichuan peppercorns based on flavoromics combined with principal component analysis. This method utilizes instrumental analysis to detect flavor-related quality indicators. Combining flavoromics technology with principal component analysis allows for a more objective and accurate evaluation of the overall flavor quality of Sichuan peppercorns than traditional sensory evaluation methods. Green Sichuan peppercorns, red Sichuan peppercorns, and red Sichuan peppercorns differ significantly in flavor quality. Combining flavoromics technology with principal component analysis allows for differentiation between green, red, and red Sichuan peppercorns, screening for significantly different flavor indicators among the three types of Sichuan peppercorns. The overall flavor quality of the three types of Sichuan peppercorns can then be ranked based on their characteristic flavor quality indicators. Therefore, this method can be used for the objective and accurate comprehensive evaluation of the flavor quality of multi-component, complex Sichuan peppercorn samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the differences in volatile aroma components of green pepper, red pepper, and red pepper in the examples; wherein (a) a principal component analysis diagram based on the content of aroma components, and (b) a heat map of the aroma component content;

[0024] Figure 2 Schematic diagram of the differences in numbing components of green, red, and red peppers in the examples; wherein: (a) total numbing factor content, (b) sanshool ratio, (c) principal component analysis based on sanshool content, (d) volcano plot of sanshool differences between green and red peppers, (e) volcano plot of sanshool differences between red and red peppers, and (f) volcano plot of sanshool differences between green and red peppers.

[0025] Figure 3 Schematic diagram of the differences in aroma components of green pepper, red pepper, and red pepper in the examples; (a) volatile oil content, (b) proportion of main aroma components, (c) principal component analysis diagram based on the content of main aroma components;

[0026] Figure 4 This is a volcano plot showing the differences in main aroma components between green pepper and red pepper in the example;

[0027] Figure 5 This is a volcano plot showing the differences in main aroma components between red bell pepper and red pepper in the examples;

[0028] Figure 6This is a volcano plot showing the differences in main aroma components between green and red Zanthoxylum bungeanum in the examples;

[0029] Figure 7 This is the principal component analysis scree plot in the embodiment;

[0030] Figure 8 Graph showing principal component analysis in the embodiment. DETAILED DESCRIPTION

[0031] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0032] Example

[0033] Determination of relevant indicators of flavor quality of Zanthoxylum bungeanum:

[0034] The composition and relative content of volatile and semivolatile compounds in green, red, and red Zanthoxylum bungeanum were determined using gas chromatography-tandem time-of-flight mass spectrometry (GC-Q-TOFMS, Agilent Technologies, USA) equipped with a three-in-one extraction head (DVB / CAR / PDMS, Guangzhou Zhida Laboratory Technology Co., Ltd., China) and a DB-5MS column (30 m × 0.32 mm ID × 0.25 μm; Agilent Technologies, California, USA). The following method was used: Dried Zanthoxylum bungeanum samples were thoroughly ground and passed through a 60-mesh sieve. 1.0 g of Zanthoxylum bungeanum powder was accurately weighed and placed in a 10-mL solid-phase microextraction headspace vial. 10 μL of o-dichlorobenzene (1,2-dichlorobenzene, 10 mg / mL) was quickly added as an internal standard, and the vial was quickly sealed with a screw cap. The headspace vial containing the sample and internal standard was equilibrated at 55°C for 5 minutes, and then extracted using a three-in-one extraction head (DVB / CAR / PDMS) at 65°C for 30 minutes. Immediately thereafter, the extraction head was inserted into the injection port at 250°C for 5 minutes. Split ratio: 80:1; Injector and transfer line temperature: 250°C; Column: DB-5MS (30 m × 0.32 mm ID × 0.25 μm); Temperature program: 40°C for 2 minutes, then ramp to 150°C at 3°C / min, and finally ramp to 250°C at 5°C / min and hold for 2 minutes. Ion source temperature: 250°C. Ion source: Electron Impact (EI); Ionization mode: Positive; Collision energy: 70 eV; Mass spectrometry acquisition range: m / z 100-1000.

[0035] The content of differential aroma compounds was determined using a GC2010plus gas chromatograph (equipped with a FID hydrogen flame ionization detector, Shimadzu Corporation, Japan) using the following method:

[0036] Dried Zanthoxylum bungeanum was ground into a powder and passed through a 60-mesh sieve. 2.0 g of Zanthoxylum bungeanum powder was accurately weighed and placed in a 20 mL headspace vial. 10 μL of o-dichlorobenzene (1,2-dichlorobenzene, 10 mg / mL) was quickly added as an internal standard, and the vial was quickly sealed with a screw cap for analysis. The headspace vial containing the sample and internal standard was equilibrated at 40°C for 15 minutes. The vial was then extracted with a headspace extraction head at 50°C for 10 minutes. The headspace extraction head was then immediately inserted into the injection port at 250°C for 5 minutes. The syringe and transfer line temperature was 110°C. The column was an HP-5 capillary column (30 m × 0.32 mm × 0.25 μm). The temperature program was as follows: 50°C for 2 minutes, then ramped to 95°C at 15°C / min, held for 2 minutes, then ramped to 130°C at 5°C / min, held for 1 minute, and then ramped to 260°C at 8°C / min, held for 3 minutes. Vaporization chamber temperature: 32°C, FID temperature: 260°C, carrier gas: nitrogen, carrier gas pressure: 37.8 kPa, splitless injection.

[0037] The sanshool content was determined by LC20A high performance liquid chromatograph (equipped with a UV detector, managed by Shimadzu Corporation (China) of Japan), according to the method of “Liquid chromatography method for the determination of the total content of sanshoamide in Zanthoxylum bungeanum and its processed products (GH / T1291-2020)”.

[0038] The total cannabinoid content was determined by UV-visible spectrophotometer (equipped with quartz cuvette and deuterium lamp), according to the method of "Determination of the total content of zanthoxylum bungeanum and its processed products - Ultraviolet spectrophotometry (GH / T 1290-2020)".

[0039] The main contributing indicators for screening the quality differences of pepper:

[0040] The data processing conditions are as follows: the linear retention index is calculated by using normal alkanes (C7-C 40) was calculated. The compounds were determined by comparing their similarity with those in the NIST 21 database with a minimum match of 80%-85%, and by comparing the linear retention index values ​​with those in the NIST library with an error range of 20-50. The relative content of volatile compounds was relatively quantified by the peak area ratio of any volatile compound. Unsupervised principal component analysis (PCA), heatmap, analysis of variance, and multiple unpaired t-test were performed using metaboanalyst 5.0 and Graphpad Prism 10.1.2. Inter-group significance analysis was based on one-way analysis of variance (ANOVA) using SPSS Statistics 23.0 software (SPSS Inc., Chicago, IL, USA).

[0041] In this example, 11 batches of green pepper, 13 batches of red pepper and 10 batches of red pepper samples of the same grade in Sichuan Province were selected for non-targeted screening of volatile flavor compounds. A total of 254 volatile flavor compounds were detected in the 34 batches of pepper samples. Figure 1 As shown in (a), based on the non-targeted screening of volatile flavor components, green pepper, red pepper and red pepper can be clearly distinguished and the differences between the groups are small, indicating that there are significant differences in the volatile flavor components of the three types of pepper. The volatile flavor components are clustered, as shown in Figure 1 As shown in (b), based on volatile flavor components, red pepper, red-transferred pepper, and green pepper each clustered into one category. Red-transferred pepper and green pepper exhibited similar volatile flavor components, clustering into a single category and clearly distinguishing them from red pepper. The results indicate that red-transferred pepper and green pepper share similar volatile flavor components, while red-transferred pepper and red pepper differ significantly. Based on the difference fold (FC>2 or <0.5), T-test (p<0.01) and VIP value (>1), 21 significantly different aroma components were screened out among green pepper, red pepper and red pepper, including α-pinene, levorotatory α-pinene, sabinene, β-pinene, myrcene, β-phellandrene, D-limonene, eucalyptol, ocimene, γ-terpinene, linalool oxide, terpinolene, linalool, 4-terpineol, terpineol, nerol, linalyl acetate, terpineyl acetate, neryl acetate, geranyl acetate and β-caryophyllene.

[0042] This example studies the typical flavor indexes of Sichuan pepper: total numbing factor content and the content of four main sanshools, including 19 batches of green pepper, 20 batches of red pepper, and 23 batches of red pepper. Figure 2 .like Figure 2 As shown in (c), based on the total numbing and sanshool contents, there are significant differences between green pepper, red pepper and red pepper. Further analysis of the significant differences in numbing substances between green pepper, red pepper and red pepper, such as Figure 2 As shown in (d), hydroxy-γ-sanshool (dry tingling sensation) is a substance with significant differences between green pepper and red pepper. There are significant differences in the contents of hydroxy-β-sanshool (spicy taste), hydroxy-γ-sanshool and hydroxy-ε-sanshool (numbing and tingling sensation) between red pepper and red pepper ( Figure 2 e). Hydroxy-α-sanshool (long-lasting tingling sensation), hydroxy-β-sanshool and hydroxy-γ-sanshool can be used as significant differences between green and red peppers. Figure 2 f). In conclusion, the sanshool compositions differed greatly among the three types of Zanthoxylum bungeanum.

[0043] Based on the results of non-targeted screening, the study determined the contents of 20 significantly different substances such as D-limonene and volatile oils among the three types of Zanthoxylum bungeanum. Figure 4 As shown in the figure, β-phellandrene, β-pinene, γ-terpinene, sabinene and linalool can be considered as the different aroma substances between red pepper and green pepper. β-pinene, D-limonene, sabinene, myrcene and linalool are the significant different aroma substances between red pepper and red pepper ( Figure 5 The aroma compounds that differ significantly between green and red Sichuan peppercorns include D-limonene, myrcene, sabinene, and linalool ( Figure 6 ).

[0044] The principal component analysis method was used to comprehensively score the above flavor quality index data:

[0045] KMO, Bartlett test and correlation test were performed on 21 flavor indices of 61 pepper samples. The structure showed that the Kaiser-Meyer-Olkin metric value was 0.742, the significance of Bartlett's sphericity test was 0.000, and the correlation between the indices of all samples was basically greater than 0.3, which met the conditions for principal component analysis and could be used for principal component analysis.

[0046] Table 1 Total variance explained

[0047]

[0048] As shown in Table 1, three principal components were extracted from the above data, with a cumulative variance contribution of 89.514%, representing comprehensive information on Sichuan peppercorn quality. The first principal component had a variance contribution of 50.027%, the highest of the three principal components, indicating its greatest influence on Sichuan peppercorn quality. Based on Tables 1 and 2, linear combinations of the three principal components and the standardized data for the original 21 Sichuan peppercorn flavor quality indices were calculated. The expressions for each principal component are: (x represents the standardized data for each Sichuan peppercorn quality indices):

[0049] y1=-0.298x 23 -0.285x 21 -0.282x<h2 style=";text-align:left;direction:ltr"> 25 <h2 style=";text-align:left;direction:ltr"> +0.270x<h2 style=";text-align:left;direction:ltr"> 10 <h2 style=";text-align:left;direction:ltr"> +0.266x8+0.265x9+0.264x<h2 style=";text-align:left;direction:ltr"> 19 <h2 style=";text-align:left;direction:ltr"> +0.254x6-0.247x<h2 style=";text-align:left;direction:ltr"> 26 <h2 style=";text-align:left;direction:ltr"> -0.247x<h2 style=";text-align:left;direction:ltr"> 27 <h2 style=";text-align:left;direction:ltr"> +0.232x<h2 style=";text-align:left;direction:ltr"> 17 <h2 style=";text-align:left;direction:ltr"> -0.227x<h2 style=";text-align:left;direction:ltr"> 20 <h2 style=";text-align:left;direction:ltr"> +0.202x3-0.157x<h2 style=";text-align:left;direction:ltr"> 22 <h2 style=";text-align:left;direction:ltr"> +0.039x<h2 style=";text-align:left;direction:ltr"> 16 <h2 style=";text-align:left;direction:ltr"> +0.055x7+0.098x<h2 style=";text-align:left;direction:ltr"> 12 <h2 style=";text-align:left;direction:ltr"> +0.025x<h2 style=";text-align:left;direction:ltr"> 18 <h2 style=";text-align:left;direction:ltr"> -0.188x<h2 style=";text-align:left;direction:ltr"> 14 <h2 style=";text-align:left;direction:ltr"> -0.190x<h2 style=";text-align:left;direction:ltr"> 24 <h2 style=";text-align:left;direction:ltr"> +0.154x5;<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0050] <h2 style=";text-align:left;direction:ltr"> y2=0.064x<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> +0.105x<h2 style=";text-align:left;direction:ltr"> 21 <h2 style=";text-align:left;direction:ltr"> +0.146x<h2 style=";text-align:left;direction:ltr"> 25 <h2 style=";text-align:left;direction:ltr"> +0.159x<h2 style=";text-align:left;direction:ltr"> 10 <h2 style=";text-align:left;direction:ltr"> +0.158x8+0.171x9+0.114x<h2 style=";text-align:left;direction:ltr"> 19 <h2 style=";text-align:left;direction:ltr"> +0.049x6+0.216x<h2 style=";text-align:left;direction:ltr"> 26 <h2 style=";text-align:left;direction:ltr"> +0.216x<h2 style=";text-align:left;direction:ltr"> 27 <h2 style=";text-align:left;direction:ltr"> +0.142x<h2 style=";text-align:left;direction:ltr"> 17 <h2 style=";text-align:left;direction:ltr"> +0.248x<h2 style=";text-align:left;direction:ltr"> 20 <h2 style=";text-align:left;direction:ltr"> +0.152x3-0.182x<h2 style=";text-align:left;direction:ltr"> 22 <h2 style=";text-align:left;direction:ltr"> +0.361x<h2 style=";text-align:left;direction:ltr"> 16 <h2 style=";text-align:left;direction:ltr"> +0.357x7+0.339x<h2 style=";text-align:left;direction:ltr"> 12 <h2 style=";text-align:left;direction:ltr"> +0.303x<h2 style=";text-align:left;direction:ltr"> 18 <h2 style=";text-align:left;direction:ltr"> +0.280x<h2 style=";text-align:left;direction:ltr"> 14 <h2 style=";text-align:left;direction:ltr"> +0.280x<h2 style=";text-align:left;direction:ltr"> 24 <h2 style=";text-align:left;direction:ltr"> +0.125x5;<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0051] <h2 style=";text-align:left;direction:ltr"> y3=0.085x<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> +0.031x<h2 style=";text-align:left;direction:ltr"> 21 <h2 style=";text-align:left;direction:ltr"> +0.039×x<h2 style=";text-align:left;direction:ltr"> 25 <h2 style=";text-align:left;direction:ltr"> -0.091x<h2 style=";text-align:left;direction:ltr"> 10 <h2 style=";text-align:left;direction:ltr"> -0.138x8-0.161x9-0.073x<h2 style=";text-align:left;direction:ltr"> 19 <h2 style=";text-align:left;direction:ltr"> -0.156x6-0.037x<h2 style=";text-align:left;direction:ltr"> 26 <h2 style=";text-align:left;direction:ltr"> -0.037x<h2 style=";text-align:left;direction:ltr"> 27 <h2 style=";text-align:left;direction:ltr"> -0.080x<h2 style=";text-align:left;direction:ltr"> 17 <h2 style=";text-align:left;direction:ltr"> -0.048x<h2 style=";text-align:left;direction:ltr"> 20 <h2 style=";text-align:left;direction:ltr"> +0.510x3+0.225x<h2 style=";text-align:left;direction:ltr"> 22 <h2 style=";text-align:left;direction:ltr"> -0.040x<h2 style=";text-align:left;direction:ltr"> 16 <h2 style=";text-align:left;direction:ltr"> -0.130x7-0.016x<h2 style=";text-align:left;direction:ltr"> 12 <h2 style=";text-align:left;direction:ltr"> +0.283x18 -0.074x 14 -0.053x 24 +0.691x5.

[0052] x3, x 5～ x 10 、x 12 、x 14 、x 16～ x 27 The data after standardization are hydroxy-β-sanshool, hydroxy-ε-sanshool, volatile oil, α-pinene, levorotatory-α-pinene, sabinene, β-pinene, β-phellandrene, eucalyptol, γ-terpinene, linalool oxide, terpinolene, linalool, 4-terpineol, terpineol, nerol, linalyl acetate, terpineyl acetate, neryl acetate, geranyl acetate, and β-caryophyllene.

[0053] The weights of each principal component were determined based on their normalized relative variance contribution rates. Based on these weights, a comprehensive evaluation function for Zanthoxylum bungeanum flavor quality was constructed: Y = 0.50027y1 + 0.34256y2 + 0.05230y3. The Y value was positively correlated with the flavor quality of Zanthoxylum bungeanum. This evaluation function can comprehensively reflect the flavor quality of Zanthoxylum bungeanum.

[0054] Table 2 shows the comprehensive flavor scores of the 61 Sichuan peppercorn samples. Based on the 21 flavor indicators mentioned above, the overall flavor quality of different Sichuan peppercorn categories varied significantly. Overall, the ranking of comprehensive flavor quality was: red peppercorn > green peppercorn > red peppercorn.

[0055]

[0056]

[0057]

[0058]

[0059] The above results show that the flavor quality of green pepper, red pepper and red pepper can be comprehensively evaluated by using flavoromics combined with principal component analysis.

[0060] In summary, the present invention provides a method for comprehensively evaluating the flavor quality of Sichuan peppercorns based on flavoromics combined with principal component analysis. This method utilizes instrumental analysis to detect flavor-related quality indicators. Based on flavoromics technology combined with principal component analysis, it more objectively and accurately evaluates the overall flavor quality of Sichuan peppercorns compared to traditional sensory evaluation methods. Green Sichuan peppercorns, red Sichuan peppercorns, and red Sichuan peppercorns differ significantly in flavor quality. Flavoromics technology combined with principal component analysis can distinguish green Sichuan peppercorns, red Sichuan peppercorns, and red Sichuan peppercorns, screening out significantly different flavor indicators among the three types of Sichuan peppercorns, and ranking the overall flavor quality of the three types of Sichuan peppercorns based on their characteristic flavor quality indicators. Therefore, this method can be used for the objective and accurate comprehensive evaluation of the flavor quality of multi-component, complex Sichuan peppercorn samples.

[0061] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

[0062] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A comprehensive evaluation method for Zanthoxylum bungeanum flavor quality based on flavoromics and principal component analysis, characterized in that: The following steps are involved: (1) Determine the flavor quality evaluation indexes of different types of Zanthoxylum bungeanum; (2) Analyze the flavor quality evaluation index results measured above based on flavoromics technology to screen the main contributing indicators to the quality differences of Zanthoxylum bungeanum; (3) The principal component analysis method was used to comprehensively score the main contributing indicators of Zanthoxylum bungeanum flavor quality; (4) Based on the comprehensive scoring results, select the pepper categories with high flavor.

2. The method for comprehensive evaluation of Zanthoxylum bungeanum flavor quality based on flavoromics and principal component analysis according to claim 1, characterized in that: In step (1), the categories of Sichuan pepper include green Sichuan pepper, red green Sichuan pepper and red Sichuan pepper; wherein, red green Sichuan pepper refers to Sichuan pepper whose skin color has changed to slightly reddish brown due to the green Sichuan pepper that has not been harvested in time.

3. The method for comprehensive evaluation of Zanthoxylum bungeanum flavor quality based on flavoromics and principal component analysis according to claim 1, characterized in that: In step (1), the evaluation index of Zanthoxylum bungeanum flavor quality includes total numbing factor, hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, hydroxy-ε-sanshool, volatile oil, α-pinene, levorotatory-α-pinene, sabinene, β-pinene, myrcene, β-phellandrene, D-limonene, eucalyptol, ocimene, γ-terpinene, linalool oxide, terpinolene, linalool, 4-terpineol, terpineol, nerol, linalyl acetate, terpineyl acetate, neryl acetate, geranyl acetate, and β-caryophyllene.

4. The method for comprehensive evaluation of Zanthoxylum bungeanum flavor quality based on flavoromics and principal component analysis according to claim 1, wherein: In step (1), flavoromics techniques include one-way analysis of variance, two-way analysis of variance, correlation analysis, multiple unpaired t-test and cluster analysis.

5. The method for comprehensive evaluation of Zanthoxylum bungeanum quality based on flavoromics and principal component analysis according to claim 1, wherein In step (2), the main contributing indicators to the quality difference of Zanthoxylum bungeanum include total linalool, hydroxy-α-sanshool, hydroxy-β-sanshool, hydroxy-γ-sanshool, hydroxy-ε-sanshool, volatile oil, β-phellandrene, β-pinene, γ-terpinene, sabinene, linalool, D-limonene and myrcene.

6. The method for comprehensive evaluation of Zanthoxylum bungeanum quality based on flavoromics and principal component analysis according to claim 1, characterized in that: In step (3), the comprehensive score calculation expression in the principal component analysis method is: Y = 0.50027y1 + 0.34256y2 + 0.05230y3, and the Y value is positively correlated with the flavor quality of Sichuan pepper; The calculation formulas for y1, y2, and y3 are as follows: y1=-0.298x 23 -0.285x 21 -0.282x 25 +0.270x 10 +0.266x8+0.265x9+0.264x 19 +0.254x6-0.247x 26 -0.247x 27 +0.232x 17 -0.227x 20 +0.202x3-0.157x 22 +0.039x 16 +0.055x7+0.098x 12 +0.025x 18 -0.188x 14 -0.190x 24 +0.154x5; y2=0.064x 23 +0.105x 21 +0.146x 25 +0.159x 10 +0.158x8+0.171x9+0.114x 19 +0.049x6+0.216x 26 +0.216x 27 +0.142x 17 +0.248x 20 +0.152x3-0.182x 22 +0.361x 16 +0.357x7+0.339x12+0.303x 18 +0.280x 14 +0.280x 24 +0.125x5; <h2 style=";text-align:left;direction:ltr">y3=0.085x<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> +0.031x<h2 style=";text-align:left;direction:ltr"> 21 <h2 style=";text-align:left;direction:ltr"> +0.039×x<h2 style=";text-align:left;direction:ltr"> 25 <h2 style=";text-align:left;direction:ltr"> -0.091x<h2 style=";text-align:left;direction:ltr"> 10 <h2 style=";text-align:left;direction:ltr"> -0.138x8-0.161x9-0.073x<h2 style=";text-align:left;direction:ltr"> 19 <h2 style=";text-align:left;direction:ltr"> -0.156x6-0.037x<h2 style=";text-align:left;direction:ltr"> 26 <h2 style=";text-align:left;direction:ltr"> -0.037x<h2 style=";text-align:left;direction:ltr"> 27 <h2 style=";text-align:left;direction:ltr"> -0.080x<h2 style=";text-align:left;direction:ltr"> 17 <h2 style=";text-align:left;direction:ltr"> -0.048x<h2 style=";text-align:left;direction:ltr"> 20 <h2 style=";text-align:left;direction:ltr"> +0.510x3+0.225x<h2 style=";text-align:left;direction:ltr"> 22 <h2 style=";text-align:left;direction:ltr"> -0.040x<h2 style=";text-align:left;direction:ltr"> 16 <h2 style=";text-align:left;direction:ltr"> -0.130x7-0.016x<h2 style=";text-align:left;direction:ltr"> 12 <h2 style=";text-align:left;direction:ltr"> +0.283x<h2 style=";text-align:left;direction:ltr"> 18 <h2 style=";text-align:left;direction:ltr"> -0.074x<h2 style=";text-align:left;direction:ltr"> 14 <h2 style=";text-align:left;direction:ltr"> -0.053x<h2 style=";text-align:left;direction:ltr"> 24 <h2 style=";text-align:left;direction:ltr"> +0.691x5; x3, x 5～ x 10 、x 12 、x 14 、x 16～ x 27 The data after standardization are hydroxy-β-sanshool, hydroxy-ε-sanshool, volatile oil, α-pinene, levorotatory-α-pinene, sabinene, β-pinene, β-phellandrene, eucalyptol, γ-terpinene, linalool oxide, terpinolene, linalool, 4-terpineol, terpineol, nerol, linalyl acetate, terpineyl acetate, neryl acetate, geranyl acetate, and β-caryophyllene.

Images