Analysis and detection method for grading base liquor of white spirit based on GC-MS (Gas Chromatography-Mass Spectrometer) combined with chemometrics

Abstract

The invention discloses an analysis and detection method for grading baijiu base liquor based on GC-MS combined with chemometrics. The analysis and detection method comprises the following steps: S1, preparing materials and reagents; s2, material and reagent sample introduction; s3, performing GC-MS (gas chromatography-mass spectrometry) analysis; s4, component quantitative analysis; s5, performing chemometrics analysis; the method comprises the steps of S1, pre-processing, S2, pre-processing, S6, model construction and verification, S7, analysis result output and the like, so that quick and accurate grading of different grades of baijiu base liquor is realized, powerful support is provided for quality control and product grading of baijiu production enterprises, meanwhile, an automatic sample injector is arranged in the step S2 to carry out automatic sample injection detection on samples, and the detection accuracy is greatly improved. According to the automatic sample injector, the analysis and detection efficiency of the base liquor of the white spirit is greatly improved, manual sample injection is not needed, the cleaning device is further arranged in the automatic sample injector to meet the requirements for flushing and cleaning and reciprocating wiping and drying treatment of the sampling needle, and the analysis and detection accuracy and quality of the sample are guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of liquor base analysis and detection, and specifically to an analysis and detection method for grading liquor base liquor based on GC-MS combined with chemometrics. Background Art

[0002] Liquor has a long history in my country. It is the crystallization of my country's history and culture for thousands of years and is one of the six major distilled spirits in the world. The main ingredients in liquor are water and ethanol, and the decisive trace ingredients account for only about 2%. The base wine is the original wine that does not undergo blending during the fermentation process. Its quality and flavor affect the subsequent blending and mixing processes and the quality of the finished wine. Therefore, by exploring the composition of flavor substances in liquor and grading different types of base wine, it is of great significance to the company's production management and product quality control.

[0003] At present, gas chromatography-mass spectrometry (GC-MS), gas chromatography-ion mobility spectrometry (GC-IMS), nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), liquid chromatography-mass spectrometry (LC-MS) and other detection methods have been widely used in flavor foods such as liquor. GC-MS technology has the advantages of high sensitivity and strong anti-interference ability, and can accurately identify and quantitatively analyze complex components. It has excellent performance in food, chemistry and other fields. With the continuous optimization and improvement of the NIST database, it is more convenient for users to use.

[0004] However, gas chromatography-mass spectrometry (GC-MS) technology is widely used in the analysis of liquor components due to its high sensitivity, high resolution and strong quantitative ability. However, it is difficult for a single GC-MS technology to fully reflect the complex components of the liquor base and their interrelationships, and it needs to be combined with chemometric methods for in-depth analysis. Summary of the invention

[0005] The purpose of the present invention is to provide an analytical detection method for grading base liquor of liquor based on GC-MS combined with chemometrics, so as to solve the problems raised in the above background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical scheme: a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, comprising the following steps:

[0007] S1. Preparation of materials and reagents: Select the liquor base wine sample to be tested according to the base wine grade, dilute it to an appropriate concentration according to a certain ratio, and use it as the sample to be tested, and prepare the reagents according to the ratio;

[0008] S2. Material and reagent injection: The samples to be tested are sequentially input into the gas chromatograph mass spectrometer through an automatic injector;

[0009] S3. GC-MS analysis: Use gas chromatography-mass spectrometry (GC-MS) to perform qualitative and quantitative analysis on the volatile flavor substances in the sample, and obtain mass spectra and chromatograms of multiple components in the sample to be tested;

[0010] S4. Quantitative analysis of components: Quantitative analysis of various components in the liquor base wine is performed using the internal standard method to obtain the concentration or relative content of each component;

[0011] S5. Chemometric analysis: The quantitative analysis results were input into chemometric software, and partial least squares discriminant analysis (PLS-DA), principal component analysis (PCA), hierarchical cluster analysis (HCA) and other methods were used to classify and grade the liquor base wines;

[0012] S6. Model construction and validation: Based on the screened key differential compounds and important aroma components, machine learning algorithms were used to construct discriminant models, including random forest (RF), support vector machine (SVM) and logistic regression (LR). The constructed models were validated using the test set to evaluate the accuracy, recall, precision and F1 value of the models.

[0013] S7. Analysis result output: Based on the discrimination results of the model, the classification information of different grades of liquor base wine is output, and a grading report is output.

[0014] Preferably, in step S1, 10 samples are taken from the four grades of base wine, namely, premium, primary, secondary, and discarded wine, for a total of 40 wine samples.

[0015] Preferably, the reagent in step S1 is composed of one or more of ether, acetaldehyde, trioxymethylene, acetoin, n-propanol, propylene glycol, n-butanol, isobutanol, sec-butanol, 2,3-butanediol, and n-pentanol.

[0016] Preferably, the GC-MS analysis step comprises the following steps:

[0017] S4a, sample processing: the base wine sample is subjected to appropriate pre-processing, such as dilution, filtration, etc.;

[0018] S4b, GC-MS condition setting: select appropriate chromatographic column, temperature program, carrier gas flow rate and other conditions, as well as mass spectrometry ion source type, electron energy and other parameters;

[0019] S4c, data acquisition: The chromatogram of the sample is collected by GC-MS instrument, and the flavor substances are qualitatively and quantitatively analyzed.

[0020] Preferably, the mass spectrometry conditions in step S4b are: electron ionization source; electron energy 70 eV; ion source temperature 280° C.; transmission line temperature 260° C.; mass scanning range 25-550 m / z.

[0021] Preferably, the gas chromatography conditions of the chromatogram in step S4c are: 30m×0.25mm×0.25μm DB-WAXUI capillary column; temperature program: split ratio 40:1; carrier gas: helium (purity 99.999%); flow rate: 1.0mL / min; injection volume: 1μL; injection mode: automatic injection.

[0022] Preferably, in step S4, the internal standard method is used to quantitatively analyze the various components in the liquor base wine, and the OAV of each volatile component in the base wine needs to be calculated by the aroma intensity. The larger the OAV value, the greater the contribution of the component to the aroma of the base wine.

[0023] Preferably, before performing step S5, statistical software is used to normalize the data obtained from the test to eliminate the dimensional differences between different samples.

[0024] Preferably, the data normalization processing is performed using IBM SPSS Statistics software.

[0025] Preferably, the model construction and verification in step S6 may explore other advanced machine learning algorithms, such as deep learning, in addition to algorithms such as random forest, SVM, and logistic regression.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention realizes fast and accurate classification of different grades of liquor base wines through the steps of S1, material and reagent preparation; S2, material and reagent sampling; S3, GC-MS analysis; S4, component quantitative analysis; S5, chemometric analysis; S6, model construction and verification and S7, analysis result output, etc., and provides strong support for quality control and product classification of liquor production enterprises. At the same time, in step S2, an automatic sampler is set to perform automatic sampling and detection of samples, which greatly improves the analysis and detection efficiency of the liquor base wine, and manual sampling is not required. A cleaning device is also set inside the automatic sampler to meet the flushing and cleaning of the sampling needle and the reciprocating wiping and drying treatment, so as to ensure the accuracy and quality of sample analysis and detection.

[0028] The setting of the cleaning chamber and the drying chamber means that after completing the sampling activity, the sampling needle can enter the cleaning chamber and the drying chamber respectively to carry out cleaning and drying activities, to ensure the cleanliness of the outside, to avoid cross-mixing of samples, and to affect the accuracy of analysis and detection.

[0029] The setting of the cleaning structure, that is, the hollow tube installed in the limiting pipe, can rotate with the driven wheel on one side, so as to conveniently realize the rotation of the stirring frame connected to the bottom and the second bevel gear. As the second bevel gear rotates, the side gears connected on both sides of the upper end of the meshing transmission will be engaged. In this way, the rotation of the first bevel gear will be driven accordingly. Therefore, the cleaning frame arranged on the upper end of the first bevel gear will rotate synchronously with the stirring frame in an opposite circle to assist in stirring the cleaning liquid inside the cleaning chamber, so that the cleaning liquid can assist in flushing and cleaning the sampling needle. At the same time, the cleaning frame rotating in the opposite direction can realize scraping and cleaning inside the cleaning chamber, thereby ensuring the cleanliness of the inside of the cleaning chamber and avoiding the occurrence of pollution problems in the cleaning chamber.

[0030] The setting of the drying structure, that is, when the main gear rotates with the driven wheel on one side, the rotation of the meshing sub-gears on both sides can be realized. In this way, the rotating drums on both sides will rotate simultaneously, and the first connecting block and the second connecting block connected to the circulation groove opened on the outside of the rotating drum through the pin shaft can move up and down alternately. In this way, the cleaning layer and the heating wire arranged inside the first connecting block and the second connecting block will move up and down alternately to quickly wipe and clean the outside of the sampling needle and heat and dry it, so that the sampling needle can be quickly put into sampling use, greatly accelerating the efficiency of subsequent analysis and detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the analysis and detection process of the present invention;

[0032] Figure 2 It is a schematic diagram of the structure of the automatic sample injector of the present invention;

[0033] Figure 3 It is a schematic diagram of the structure of the sampling assembly of the present invention;

[0034] Figure 4 It is a schematic diagram of the structure of the cleaning device of the present invention;

[0035] Figure 5 It is a schematic diagram of the internal structure of the cleaning device of the present invention;

[0036] Figure 6 This is a schematic diagram of the internal structure of the cleaning and drying component of the present invention;

[0037] Figure 7 It is a schematic diagram of the three-dimensional structure of the cleaning structure of the present invention;

[0038] Figure 8 It is a schematic diagram of the internal structure of the drying structure of the present invention;

[0039] Fig. 9 It is a schematic diagram of the three-dimensional structure of the first connecting block of the present invention;

[0040] Fig.10 It is a schematic diagram of the three-dimensional structure of the second connecting block of the present invention.

[0041] In the figure: base 1, display screen 2, control panel 3, sample storage 4, first slide rail 5, mobile rack 6, second slide rail 7, connection box 8, cylinder 9, sampling assembly 10, connection seat 101, fixing block 102, pressure cap joint 103, sampling needle 104, vertical rod 105, first spring 106, bottle stop block 107, hollow cylinder 108, second spring 109, needle guard tube 1010, cleaning device 11, box body 111, top plate 112, opening 113, cleaning chamber 114, drying chamber 115, liquid inlet pipe 116, first liquid outlet pipe 117, second liquid outlet pipe 118, cleaning and drying assembly 11 9. Servo motor 1191, driving wheel 1192, toothed transmission belt 1193, driven wheel 1194, cleaning structure 1195, limiting pipe 11951, hollow tube 11952, turntable 11953, cleaning frame 11954, first bevel gear 11955, side gear 11956, second bevel gear 11957, stirring frame 11958, drying structure 1196, main gear 11961, sub gear 11962, rotating drum 11963, protective shell 11964, first connecting block 11965, pin 11966, cleaning layer 11967, second connecting block 11968, heating wire 11969. DETAILED DESCRIPTION

[0042] In order to further explain the technical solution of the present invention, it is described in detail below through specific embodiments.

[0043] See also Figure 1 The present invention provides a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, comprising the following steps:

[0044] S1. Preparation of materials and reagents: Select the liquor base wine sample to be tested according to the base wine grade, dilute it to an appropriate concentration according to a certain ratio, and use it as the sample to be tested, and prepare the reagents according to the ratio;

[0045] S2. Material and reagent injection: The samples to be tested are input into the gas chromatograph mass spectrometer in sequence through the automatic sample injector;

[0046] S3. GC-MS analysis: Use gas chromatography-mass spectrometry (GC-MS) to perform qualitative and quantitative analysis on the volatile flavor substances in the sample, and obtain mass spectra and chromatograms of multiple components in the sample to be tested;

[0047] S4. Quantitative analysis of components: Quantitative analysis of various components in the liquor base wine is performed using the internal standard method to obtain the concentration or relative content of each component;

[0048] S5. Chemometric analysis: The quantitative analysis results were input into chemometric software, and partial least squares discriminant analysis (PLS-DA), principal component analysis (PCA), hierarchical cluster analysis (HCA) and other methods were used to classify and grade the liquor base wines;

[0049] S6. Model construction and validation: Based on the screened key differential compounds and important aroma components, machine learning algorithms were used to construct discriminant models, including random forest (RF), support vector machine (SVM) and logistic regression (LR). The constructed models were validated using the test set to evaluate the accuracy, recall, precision and F1 value of the models.

[0050] S7. Analysis result output: Based on the discrimination results of the model, the classification information of different grades of liquor base wine is output, and a grading report is output.

[0051] Among them, in the step S1, 10 samples of the samples to be tested are respectively extracted from four grades of base wine, namely, superior grade, primary grade, secondary grade, and discarded lees, for a total of 40 wine samples.

[0052] Wherein, the reagent in step S1 is composed of one or more of ether, acetaldehyde, trioxymethylene, acetoin, n-propanol, propylene glycol, n-butanol, isobutanol, sec-butanol, 2,3-butanediol, and n-pentanol.

[0053] Wherein, the GC-MS analysis step comprises the following steps:

[0054] S4a, sample processing: the base wine sample is subjected to appropriate pre-processing, such as dilution, filtration, etc.;

[0055] S4b, GC-MS condition setting: select appropriate chromatographic column, temperature program, carrier gas flow rate and other conditions, as well as mass spectrometry ion source type, electron energy and other parameters;

[0056] S4c, data acquisition: The chromatogram of the sample is collected by GC-MS instrument, and the flavor substances are qualitatively and quantitatively analyzed.

[0057] The mass spectrometry conditions in step S4b are: electron ionization source; electron energy 70 eV; ion source temperature 280° C.; transmission line temperature 260° C.; and mass scanning range 25 to 550 m / z.

[0058] Wherein, the gas chromatography conditions of the chromatogram in step S4c are: 30m×0.25mm×0.25μm DB-WAXUI capillary column; temperature program: starting temperature 40°C, holding time 2min, rising to 85°C at 5°C / min, holding for 2min, rising to 110°C at 8°C / min, rising to 120°C at 4°C / min, holding for 1min, rising to 220°C at 5°C / min, holding for 7min; injection port temperature maintained at 250°C; split ratio 40:1. Carrier gas: helium (purity 99.999%); flow rate: 1.0mL / min; injection volume: 1μL; injection mode: automatic injection.

[0059] Among them, in step S4, the internal standard method is used to quantitatively analyze the various components in the liquor base wine, and the OAV of each volatile component in the base wine needs to be calculated by the aroma intensity. The larger the OAV value, the greater the contribution of the component to the aroma of the base wine.

[0060] Before the step S5 is performed, statistical software is used to normalize the data obtained by the test to eliminate the dimensional differences between different samples.

[0061] The data normalization process is performed using IBM SPSS Statistics software.

[0062] Among them, in addition to algorithms such as random forest, SVM, and logistic regression, the model construction and verification in step S6 can also explore other advanced machine learning algorithms, such as deep learning.

[0063] Table 1 Aroma activity values ​​of various flavor compounds in different grades of base liquor

[0064]

[0065]

[0066]

[0067] Note: “-” means no threshold was found

[0068] OAV reflects the contribution of aroma components in the wine to the main aroma. When OAV>1, it means that the aroma component makes an important contribution to the aroma of the sample and is a key flavor compound. The OAV values ​​of various substances are shown in Table 1. In base wines of different grades, there are 21 identical substances whose OVA values ​​are greater than 1, which make an important contribution to the aroma of the base wine.

[0069] Alcohols help to enhance the sweetness and aroma of liquor. They can bring floral and fruity aroma characteristics to liquor and enrich the flavor levels of liquor. However, due to the high aroma threshold of alcohols, only six alcohols have an OAV greater than 1, namely n-propanol, n-butanol, isobutanol, isopentanol, n-hexanol and furfuryl alcohol. Among alcohols, n-butanol has the largest OAV value, and is greater than 10 in different grades of base liquors, making a greater contribution to the aroma.

[0070] Esters, as an important component of liquor, have aromatic smell and are important aroma compounds. Among the ester substances, the VIP values ​​of ethyl butyrate (fruity aroma, apple flavor), ethyl caproate (sweet aroma, cellar aroma, fruity aroma) and ethyl caprylate (pear aroma, sweet aroma, fruity aroma) are all greater than 100, which make obvious contributions to the formation of base wine aroma. Ethyl caproate is the main substance that forms the typical style of Luzhou-flavor liquor, but it is easily disturbed by external factors. The OAV value of ethyl caproate in superior and primary base wines is much greater than that of other components. Compared with secondary and discarded lees base wines, superior and primary base wines have more prominent Luzhou-flavor characteristics. In secondary and discarded lees base wines, ethyl caprylate and ethyl caproate have equal contributions to the aroma. In addition, ethyl acetate, ethyl lactate, hexyl caproate, butyl caproate, ethyl decanoate and ethyl phenylacetate make important contributions to the aroma of the base wine.

[0071] Acid compounds are an important component of liquor. They can improve the taste of the liquor and stabilize the aroma. They also have prebiotic functions such as anti-oxidation and maintaining intestinal health. There are four substances in the acid compounds with OAV>1, namely glacial acetic acid, n-butyric acid, isobutyric acid and n-valeric acid. Among them, the OAV of n-butyric acid and n-valeric acid is>10, which adds muddy and sour smells to the aroma and coordinates the aroma of the base liquor.

[0072] Aldehyde and ketone compounds contribute greatly to the aroma of the base wine due to their high content and low threshold. The OAV of acetaldehyde and acetoin is greater than 10. The OAV of acetoin in secondary and discarded lees base wines is greater than 100, which has a more significant and soft fragrance compared to superior and primary base wines.

[0073] See also Figure 2-3The automatic sampler in step S2 of this embodiment includes a base 1, a display screen 2, a control panel 3, a sample storage device 4, a first slide rail 5, a mobile rack 6, a second slide rail 7, a connecting box 8, a cylinder 9, a sampling component 10, and a cleaning device 11. The upper end of the front side of the base 1 is provided with a display screen 2, and the right side of the display screen 2 is oppositely provided with a control panel 3. The upper end of the base 1 is equipped with a sample storage device 4, and the inside of the base 1 is provided with first slide rails 5 on both sides, and the upper ends of the first slide rails 5 on both sides are connected to the bottom of the mobile rack 6. The upper end of the mobile rack 6 is equipped with a second slide rail 7, and the left side of the front end of the second slide rail 7 is connected to the connecting box 8, and the upper end of the connecting box 8 is provided with a cylinder 9, and the bottom of the cylinder 9 is connected to the sampling component 10. The left rear end of the sample storage device 4 is equipped with a cleaning device 11.

[0074] Among them, the sampling component 10 includes a connecting base 101 connected to the bottom of the cylinder 9, a fixed block 102 fastened to the front side of the connecting base 101, a pressure cap joint 103 arranged in the middle of the fixed block 102, a sampling needle 104 inserted into the pressure cap joint 103, a vertical rod 105 vertically inserted into the left and right sides of the bottom of the connecting base 101, a first spring 106 installed on the outside of the vertical rod 105, a bottle blocking block 107 connected to the lower ends of the vertical rods 105 on both sides, a hollow cylinder 108 inserted in the middle of the bottle blocking block 107, a second spring 109 connected to the upper end of the hollow cylinder 108 and a needle protection tube 1010 installed on the upper end of the hollow cylinder 108.

[0075] Specifically, when sampling is to be performed, the display screen 2 and the control panel 3 provided on the front side of the base 1 can be used to respectively realize the operation of the first slide rail 5, the second slide rail 7 and the cylinder 9. Under the drive of the first slide rail 5, the sampling assembly 10 can be moved forward and backward as a whole, and under the drive of the second slide rail 7, the sampling assembly 10 can be moved left and right, and under the drive of the cylinder 9, the sampling assembly 10 can be moved up and down. In this way, after the sample reagent bottle is placed on the upper end of the sample storage container 4, the sampling assembly 10 will accurately move to the position of the sample reagent bottle to perform the sample sampling activity;

[0076] That is, the connecting seat 101 is driven by the cylinder, so that the fixing block 102 can cooperate with the pressure cap joint 103 to realize the downward movement of the sampling needle 104. When the bottle blocking block 107 installed at the lower end of the connecting seat 101 through the vertical rod 105 and the first spring 106 is against the upper end of the sample reagent bottle, the overall squeezing and stabilization of the sample reagent bottle can be achieved, and the sampling shaking problem of the sample reagent bottle can be reduced. At this time, the sampling needle 104 will continue to move downward to be inserted into the sample reagent bottle. At the same time, during the sampling process of the sampling needle 104 being inserted into the sampling bottle, the needle guard tube 1010 provided at the upper end of the second spring 109 will be squeezed, so that the needle guard tube 1010 can realize the compression of the second spring 109 to further improve the sampling stability. The sampling needle 104 is inserted into the sample reagent bottle to transmit the sample liquid to the external gas chromatograph-mass spectrometer for data analysis activities to meet the subsequent efficient analysis and detection of the base wine grading of the liquor, without the need for manual sampling and analysis, which greatly improves the analysis efficiency.

[0077] See also Figure 4-5 The cleaning device 11 in this embodiment includes a box body 111, a top plate 112, an opening 113, a cleaning chamber 114, a drying chamber 115, a liquid inlet pipe 116, a first liquid outlet pipe 117, a second liquid outlet pipe 118 and a cleaning and drying component 119. The box body 111 is installed at the left rear end of the sample storage container 4. The top plate 112 is installed on the upper end of the box body 111. Openings 113 are provided on the left and right sides of the upper end of the top plate 112. A cleaning chamber 114 is provided on the right side of the box body 111. A drying chamber 115 is provided on the left side of the box body 111. Liquid inlet pipes 116 are connected to both sides of the right side of the outside of the box body 111. The first liquid outlet pipe 117 is connected to the lower end of the cleaning chamber 114. The second liquid outlet pipe 118 is connected to the bottom of the drying chamber 115. Cleaning and drying components 119 are installed in the cleaning chamber 114 and the drying chamber 115.

[0078] Specifically, after completing the sampling activity of a sample, the sampling needle 104 needs to be inserted into the opening 113 corresponding to the right side of the upper end of the box body 111, that is, the sampling needle 104 enters the cleaning chamber 114. At this time, the liquid inlet pipe 116 connected to the external pipeline will realize the input of cleaning liquid to achieve the flushing and cleaning of the sampling needle 104, avoid subsequent cross-mixing of samples, and affect the accuracy of analysis and detection. The waste liquid used for cleaning will be quickly discharged from the first liquid outlet pipe 117 connected to the bottom of the cleaning chamber 114, thereby ensuring that the sampling needle 104 can achieve convenient cleaning activities during continuous sampling activities.

[0079] See also Figure 6-10The cleaning and drying component 119 in this embodiment includes a servo motor 1191, a driving wheel 1192, a toothed transmission belt 1193, a driven wheel 1194, a cleaning structure 1195 and a drying structure 1196. The upper end of the servo motor 1191 is connected to the driving wheel 1192, and the outside of the driving wheel 1192 is connected to the toothed transmission belt 1193. The toothed transmission belt 1193 is connected to the driven wheels 1194 on both sides. The lower end of the right driven wheel 1194 is connected to the cleaning structure 1195, and the lower end of the left driven wheel 1194 is connected to the drying structure 1196.

[0080] The cleaning structure 1195 includes a position limiting pipe 11951, a hollow tube 11952, a turntable 11953, a cleaning frame 11954, a first bevel gear 11955, a side gear 11956, a second bevel gear 11957 and an agitating frame 11958. The position limiting pipe 11951 is firmly installed in the middle of the upper end of the cleaning chamber 114. The middle of the position limiting pipe 11951 is movably connected with the hollow tube 11952. The lower end of the position limiting pipe 11951 is rotatably connected with the turntable 11953. The bottom of the turntable 11953 is connected to the cleaning frame 11954. 1954 is connected, a first bevel gear 11955 is installed at the lower middle end of the cleaning frame 11954, side gears 11956 are meshed at the lower ends on both sides of the first bevel gear 11955, the bottoms of the side gears 11956 on both sides are meshed with the second bevel gear 11957, the middle parts of the side gears 11956 on both sides are rotatably connected to the left and right sides of the lower end of the limiting pipe 11951 respectively, the lower end of the second bevel gear 11957 is connected to the stirring frame 11958, and the lower end of the hollow tube 11952 is connected to the middle of the stirring frame 11958.

[0081] Among them, the middle part of the lower end of the limiting pipe 11951 is inserted into the middle of the first bevel gear 11955 and the second bevel gear 11957, and the first bevel gear 11955 and the second bevel gear 11957 are arranged opposite to each other up and down; the left and right sides of the lower end of the cleaning frame 11954 are arranged in a brush plate shape as a whole, and the brush plates on both sides of the bottom of the cleaning frame 11954 are against the inside of the cleaning chamber 114; the overall lateral dimension of the cleaning frame 11954 is larger than the lateral dimension of the stirring frame 11958, so that the cleaning frame 11954 and the stirring frame 11958 do not interfere with each other in rotation.

[0082] The drying structure 1196 includes a main gear 11961, a sub-gear 11962, a rotating drum 11963, a protective shell 11964, a first connecting block 11965, a pin 11966, a cleaning layer 11967, a second connecting block 11968 and a heating wire 11969. The main gear 11961 is connected to the left driven wheel 1194. The main gear 11961 is meshed with sub-gears 11962 on both sides. The lower ends of the sub-gears 11962 on both sides are connected to the rotating drum 11963. The rotating drums 11963 on both sides are installed in the protective shell 11964, and the protective shells 11964 on both sides are respectively connected to the drying chamber 115. The two sides are connected internally, a first connecting block 11965 is installed at the lower end of the left rotating drum 11963, a pin shaft 11966 is inserted at the left side of the first connecting block 11965, and the first connecting block 11965 is connected to the inside of the left rotating drum 11963 through the pin shaft 11966 arranged on the left side, a cleaning layer 11967 is provided inside the first connecting block 11965, and a second connecting block 11968 is installed at the upper end of the right rotating drum 11963, and the right side of the second connecting block 11968 is consistent with the left side of the first connecting block 11965, both are connected to the inside of the rotating drum 11963 through the pin shaft 11966, and a heating wire 11969 is installed inside the second connecting block 11968.

[0083] Among them, the structures of the left and right side rotating drums 11963 are consistent, and the outer parts of the rotating drums 11963 on both sides are integrally provided with circulation grooves, and the rotating drums 11963 are transmission connected with the pin shaft 11966 through the opened circulation grooves; the second connecting block 11968 is arranged in a concave block shape as a whole, and the size of the concave space inside the second connecting block 11968 is larger than the overall size of the first connecting block 11965, so that the first connecting block 11965 can stably pass through the concave space inside the second connecting block 11968 to meet the alternating up and down movements of the first connecting block 11965 and the second connecting block 11968, so as to achieve the simultaneous wiping and cleaning and heating and drying activities.

[0084] Specifically, in order to further improve the cleaning effect of the sampling needle 104, after the sampling needle 104 enters the cleaning chamber 114, the servo motor 1191 is driven to make the servo motor 1191 realize the rotation of the driving wheel 1192 connected to the top, and the driving wheel 1192 cooperates with the toothed transmission belt 1193 connected to the outside to realize the synchronous rotation and drive of the driven wheels 1194 connected to the left and right sides. At this time, the right driven wheel 119 will realize the rotation of the hollow tube 11952 connected in the middle. As the hollow tube 11952 rotates, the stirring frame 11958 connected to the lower end of the hollow tube 11952 will realize circular rotation. At this time, the second bevel gear 11957 connected to the upper end of the stirring frame 11958 will rotate synchronously and mesh with the side gears 119 connected to both sides of the upper end of the transmission. 56. In this way, the first bevel gear 11955 connected to the upper end of the side gears 11956 on both sides can realize the circular rotation drive of the cleaning frame 11954, that is, the cleaning frame 11954 and the stirring frame 11958 can realize synchronous opposite rotation activities. When the stirring frame 11958 rotates, the cleaning liquid in the cleaning chamber 114 can be stirred, and the cleaning liquid can be turned over to flush the sampling needle 104, thereby greatly improving the cleaning efficiency of the sampling needle 104. At the same time, the cleaning frame 11954 can realize the rotation stirring effect during the rotation process. At the same time, it can also realize the scraping cleaning inside the cleaning chamber 114 to reduce the adhesion of scale and ensure the cleanliness of the cleaning chamber 114. When the sampling needle 104 enters the cleaning chamber for multiple times, the internal environment of the sampling needle 104 is not polluted, and the cleaning effect can be guaranteed.

[0085] After the cleaning activity of the sampling needle 104 is completed, the sampling needle 104 can be inserted from the opening 113 opposite to the left side of the upper end of the box body 111, so that the sampling needle 104 is inserted into the drying chamber 115. At this time, the sampling needle 104 will pass through the left driven wheel 1194 and the middle of the main gear 11961 to stably and vertically insert into the drying chamber 115. After the insertion is completed, the lower end of the sampling needle 104 will be pre-inserted into the cleaning layer 11967 provided in the first connecting block 11965, and the heating wire 11969 provided in the second connecting block 11968 will be opposite to the upper part of the sampling needle 104. At this time, the servo motor 1191 and the heating wire 11969 can be driven again. When the servo motor 1191 is running, the left driven wheel 1194 will realize the rotation of the main gear 11961 connected to the bottom, so that the main gear 11961 will mesh with the sub-gear 11962 connected on both sides of the transmission, so that the sub-gears on both sides 11962 rotates simultaneously, and with the rotation of the sub-gears 11962 on both sides, the rotating drum 11963 connected to the lower end of the sub-gears 11962 on both sides will rotate simultaneously. In this way, the first connecting block 11965 and the second connecting block 11968 connected to the circulation grooves opened on the outside of the rotating drum 11963 on both sides through the pin shaft 11966 can realize alternating up and down movement, that is, the first connecting block 11965 can reciprocate up and down wiping movement, and the second connecting block 11968 can drive the internal heating wire 11969 to perform up and down reciprocating drying activities. In this way, the wiping and drying of the sampling needle 104 can be greatly accelerated, so that it can be quickly put into subsequent sampling use. At the same time, because the size of the concave end inside the second connecting block 11968 is larger than the overall size of the first connecting block 11965, it can be ensured that when the first connecting block 11965 and the second connecting block 11968 move up and down alternately, it is not easy to cause interference, and the stable up and down reciprocating wiping and drying effect can be guaranteed.

[0086] The above description is only a preferred example of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An analytical detection method for grading liquor base wine based on GC-MS combined with chemometrics, characterized by: The steps include: S1. Preparation of materials and reagents: Select the liquor base wine sample to be tested according to the base wine grade, dilute it to an appropriate concentration according to a certain ratio, and use it as the sample to be tested, and prepare the reagents according to the ratio; S2. Material and reagent injection: The samples to be tested are input into the gas chromatograph mass spectrometer in sequence through the automatic sample injector; S3. GC-MS analysis: Use gas chromatography-mass spectrometry (GC-MS) to perform qualitative and quantitative analysis on the volatile flavor substances in the sample, and obtain mass spectra and chromatograms of multiple components in the sample to be tested; S4. Quantitative analysis of components: Quantitative analysis of various components in the liquor base wine is performed using the internal standard method to obtain the concentration or relative content of each component; S5. Chemometric analysis: The quantitative analysis results were input into chemometric software, and partial least squares discriminant analysis (PLS-DA), principal component analysis (PCA), hierarchical cluster analysis (HCA) and other methods were used to classify and grade the liquor base wines; S6. Model construction and validation: Based on the screened key differential compounds and important aroma components, machine learning algorithms were used to construct discriminant models, including random forest (RF), support vector machine (SVM) and logistic regression (LR). The constructed models were validated using the test set to evaluate the accuracy, recall, precision and F1 value of the models. S7. Analysis result output: Based on the discrimination results of the model, the classification information of different grades of liquor base wine is output, and a grading report is output.

2. According to claim 1, a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, characterized in that: In the step S1, 10 samples are taken from four grades of base wine, namely, premium, primary, secondary, and discarded wine, for a total of 40 wine samples.

3. According to claim 1, a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, characterized in that: In step S1, the reagent is composed of one or more of ether, acetaldehyde, trioxymethylene, acetoin, n-propanol, propylene glycol, n-butanol, isobutanol, sec-butanol, 2,3-butanediol, and n-pentanol.

4. According to claim 1, a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, characterized in that: The step GC-MS analysis comprises the following steps: S4a, sample processing: the base wine sample is subjected to appropriate pre-processing, such as dilution, filtration, etc.; S4b, GC-MS condition setting: select appropriate chromatographic column, temperature program, carrier gas flow rate and other conditions, as well as mass spectrometry ion source type, electron energy and other parameters; S4c, data acquisition: The chromatogram of the sample is collected by GC-MS instrument, and the flavor substances are qualitatively and quantitatively analyzed.

5. According to claim 1, a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, characterized in that: The mass spectrometry conditions in step S4b are: electron ionization source; electron energy 70 eV; ion source temperature 280° C.; transmission line temperature 260° C.; mass scanning range 25-550 m / z.

6. According to claim 1, a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, characterized in that: The gas chromatography conditions of the chromatogram in step S4c are: 30m×0.25mm×0.25μm DB-WAXUI capillary column; temperature program: starting temperature 40°C, holding time 2min, rising to 85°C at 5°C / min, holding for 2min, rising to 110°C at 8°C / min, rising to 120°C at 4°C / min, holding for 1min, rising to 220°C at 5°C / min, holding for 7min; injection port temperature maintained at 250°C; split ratio 40:

1. Carrier gas: helium (purity 99.999%); flow rate: 1.0mL / min; injection volume: 1μL; injection mode: automatic injection.

7. According to claim 1, a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, characterized in that: In step S4, the internal standard method is used to quantitatively analyze the various components in the liquor base wine, and the OAV of each volatile component in the base wine needs to be calculated by the aroma intensity. The larger the OAV value, the greater the contribution of the component to the aroma of the base wine.

8. According to claim 1, a method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics, characterized in that: Before the step S5 is performed, statistical software is used to normalize the data obtained by the test to eliminate the dimensional differences between different samples.

9. The method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics according to claim 8, characterized in that: The data normalization processing is performed using IBM SPSS Statistics software.

10. The method for analyzing and detecting the classification of liquor base wine based on GC-MS combined with chemometrics according to claim 1, characterized in that: In addition to random forest, SVM, logistic regression and other algorithms, the model construction and verification in step S6 may also explore other advanced machine learning algorithms, such as deep learning.

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