Method for detecting white spirit by adopting white spirit gas chromatographic analysis system
By innovating the processing technology and detection methods of the gas chromatography analysis system for baijiu, the complex matrix adaptability problem of sulfide detection in baijiu has been solved, achieving efficient and accurate sulfide detection and meeting the refined detection needs of high-quality baijiu.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHAANXI JIURUSHAN WINE CO LTD
- Filing Date
- 2026-01-16
- Publication Date
- 2026-04-10
AI Technical Summary
Existing methods for detecting sulfides in baijiu (Chinese liquor) have shortcomings in adaptability to complex matrices. Some methods have incomplete pretreatment, are easily affected by alcohols and esters, and lack selectivity, making it difficult to achieve stable detection of low concentrations of sulfides and failing to meet the refined detection requirements of high-quality baijiu.
A gas chromatography analysis system for baijiu (Chinese liquor) was used. Through standardized acquisition procedures and dynamic adsorption and thermal desorption coupling technology, combined with dual-column tandem and selective detectors, complete separation of sulfides from interfering components such as alcohols and esters in baijiu was achieved. Combined with signal preprocessing and external standard correction model, the accuracy and stability of the detection were ensured.
This technology enables efficient capture and separation of sulfides in baijiu (Chinese liquor), improving the accuracy and sensitivity of detection, ensuring the credibility of detection data and the reliability of results, and providing a scientific logic for determining exceedances and a basis for quality control.
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Figure CN121830982A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of liquor analysis, more particularly, to a method for detecting liquor by using a liquor gas chromatography analysis system. BACKGROUND
[0002] The gas chromatography analysis system is a core technical means for liquor quality detection, which can realize efficient separation and accurate quantification of complex components in liquor, and is crucial for ensuring drinking safety and improving product quality; sulfides in liquor are not only key flavor substances but also safety control indicators, and excessive sulfides will produce irritating odor and harm health, so accurate detection of sulfides by the chromatography system is needed to provide reliable data support for production process optimization and quality control.
[0003] The existing liquor sulfide detection method can meet the basic detection needs, but there is still room for improvement in complex matrix adaptability, and the pre-treatment process of some methods is not complete for sulfide capture, which is easily interfered by alcohols and esters; some detection systems have insufficient selectivity, making it difficult to stably detect low-concentration sulfides, and cannot fully adapt to the fine detection needs of high-quality liquor.
[0004] In view of this, the present application provides a method for detecting liquor by using a liquor gas chromatography analysis system to solve the above problems. SUMMARY
[0005] In order to overcome the above-mentioned defects of the prior art and achieve the above-mentioned purpose, the present application provides the following technical scheme, the method comprises: S1: Ensure sample representativeness by standardized collection process to avoid volatilization or deterioration of sulfides due to environmental factors, innovative dynamic adsorption and thermal desorption coupling technology can efficiently capture trace sulfides in the sample, while eliminating the interference of alcohol content and water content matrix, the activated adsorption tube and the purification column work together to realize the enrichment and purification of target components, providing high-purity samples for subsequent chromatography analysis, and improving the detection accuracy from the source; S2: Eliminate the interference of impurities in the carrier gas and auxiliary gas by system assembly and gas purification; detector parameter adjustment and baseline stability control ensure the sensitivity and stability of the signal response, the drawing of the calibration curve provides a standard basis for quantitative calculation, and the blank verification excludes the risk of system pollution, ensuring the reliability of the subsequent detection data; S3: Through the complementary characteristics of double-column series connection, the complete separation of sulfides and alcohol, ester interference components in liquor is realized; shunt sampling and optimized column temperature program avoid chromatographic column overload, improve separation efficiency, high selectivity of the detector and signal acquisition synchronicity accurately capture the characteristic signal of target sulfides, and system cleaning after detection prevents residual components from interfering with subsequent samples, ensuring the continuity and accuracy of the detection; S4: Baseline correction and abnormal peak rejection can eliminate the influence of instrument drift and random interference on the signal, and smoothing processing can reduce noise while retaining the core information of the target peak, improving signal quality; characteristic peak identification realizes accurate identification of target sulfide through time and peak shape double judgment, filters out reliable signal data for subsequent quantitative calculation, and ensures the rigor of the results; S5: Precise quantification is achieved by correcting the model with external standard method, introducing adsorption efficiency and recovery correction coefficient to compensate for component loss in pretreatment and detection; the sample peak area is associated with the standard parameter, combined with the key variables of sampling and transfer volume, and the concentration of sulfide is directly output, which ensures the calculation process is traceable, and effectively improves the accuracy and anti-interference ability of the quantitative results; S6: By comparing with national standards and combining with uncertainty evaluation, a scientific over-standard judgment logic is constructed to avoid misjudgment; detailed warning reports are generated for over-standard cases, and the over-standard items and key parameters are clearly defined to provide direct basis for liquor production quality control and realize the practical value transformation of detection results; S7: Precision and accuracy verification confirms the method performance from the perspectives of repeatability and authenticity respectively; the determination of detection limit and quantitative limit clarifies the applicable range of the method, meets the detection needs of trace sulfide, durability verification ensures the stability and reliability of the method when the parameters fluctuate, and quality control sample insertion monitors the detection process in real time to ensure the quality and credibility of the overall detection data; Further, the step S1 comprises: S1.1: The liquor sample acquisition process is to collect three portions of liquor samples at 20 degrees Celsius constant temperature environment, with each portion accurately taking 10 milliliters; avoid aeration of the sample to generate bubbles during the sampling process; use a modified activated carbon and silica gel composite adsorbent filled adsorption tube, which is activated by nitrogen blowing for 30 minutes at 300 degrees Celsius in advance, and then sealed for standby after cooling to room temperature, to ensure that the adsorbent is free of impurities; S1.2: The liquor sample is coupled with dynamic adsorption and thermal desorption to obtain target sulfide components that can be introduced into the chromatography system; connect the sampling bottle and the adsorption tube through a polytetrafluoroethylene pipeline, set the nitrogen carrier gas flow rate to 50 milliliters per minute, and control the adsorption temperature at 25 degrees Celsius; the adsorption time lasts for 20 minutes, so that the volatile sulfides in the sample are fully captured by the adsorbent, while the alcohol content and water content are excluded; on this basis, the adsorption tube is connected to a thermal desorption instrument, and the desorption temperature is set to 250 degrees Celsius, the desorption time is 3 minutes, and the desorption gas flow rate is 80 milliliters per minute; the desorbed gas is purified through a purification column to remove high-boiling organic compounds, and the purification temperature is 80 degrees Celsius to ensure the single output of target components; S1.3: The purified target sulfide is automatically transferred to the gas chromatography injection port through a six-way valve, and the injection port temperature is maintained at 220 degrees Celsius to realize lossless sample introduction; Further, the step S2 comprises: S2.1: Build a gas chromatograph and thermal desorption instrument system and complete debugging and calibration, the chromatographic column adopts a double column series structure, the detector selects a flame photometric detector, the detector is connected with the outlet of the chromatographic column through a quartz capillary, and the connection is sealed without leakage; S2.2: The carrier gas is high-purity nitrogen, which is treated by a deoxidizing and dehydrating purifier and then connected to the system, the carrier gas column pressure is set to 0.12 MPa, and the system is operated in a constant pressure mode; the auxiliary gas is hydrogen and air, the hydrogen flow is 40 milliliters per minute, and the air flow is 400 milliliters per minute; S2.3: Start the FPD detector, set the detector temperature to 280 degrees Celsius, the photomultiplier tube voltage to 700 volts, and the sulfur filter wavelength to 394 nanometers, and stabilize for 30 minutes after ignition; S2.4: Establish a quantitative reference basis for sulfide detection, prepare five groups of gradient concentration sulfide standard mixed solutions, pretreat according to the method of step S1, inject the system, and draw a calibration curve of each target sulfide with the standard solution concentration as the abscissa and the corresponding peak area as the ordinate; Further, the step S3 comprises: S3.1: The pretreated target component is introduced into the chromatographic system through a six-way valve to realize automatic sampling of the sample after thermal desorption, the sampling mode is split sampling, the split ratio is set to 10:1, and the sampling time is 30 seconds to avoid overloading of the chromatographic column due to too large sampling amount; S3.2: Signal acquisition is completed after separation by double column series, the initial column temperature is set to 35 degrees Celsius and maintained for 3 minutes, the temperature is raised to 80 degrees Celsius at a rate of 5 degrees Celsius per minute and maintained for 2 minutes, and then the temperature is raised to 200 degrees Celsius at a rate of 15 degrees Celsius per minute and maintained for 5 minutes, so that the sulfides and alcohol and ester matrix components in the liquor are completely separated through the complementary action of the double column series; S3.3: Based on the peak regularity of the standard, the switching time of the non-polar column and the polar column is set to ensure that the non-target component is intercepted by the non-polar column, and the target sulfide is further separated by the polar column and then enters the detector; start the chromatographic workstation, set the signal acquisition frequency, and synchronize the acquisition time with the column temperature program to record the retention time, peak area and peak height data of each target sulfide; Further, the step S4 comprises: S4.1: The collected detection signal is pretreated, the polynomial fitting algorithm is used for baseline correction of the collected original signal, the correction range covers the entire acquisition period, the baseline deviation caused by instrument drift is eliminated, and the corrected signal peak is screened to eliminate interference peaks with a peak height lower than 3 times the baseline noise and retain target peaks with symmetrical peak shapes; S4.2: Based on the retention time of each target sulfide in the calibration curve, combined with the peak shape characteristics, the smoothed signal peak is qualitatively identified to determine the target sulfide corresponding to each peak, and the confirmation and identification of the target sulfide characteristic peak are completed; S4.3: The pre-processed signal data retention time, peak area and peak shape parameters are stored in CSV format, and the detection date, instrument number and sample number information are recorded to ensure data storage and traceability; Further, the step S5 comprises: S5.1: From the pre-processed signal data, the peak area corresponding to each target sulfide is extracted, and the standard sample concentration and standard sample peak area parameters in the calibration curve are recorded; S5.2: The external standard method is used to correct the model, and two correction coefficients of adsorption efficiency and recovery rate are introduced to compensate for the component loss in the pre-processing and detection process, improve the quantitative accuracy, eliminate the influence of matrix interference and operation error on the quantitative result by correcting the adsorption efficiency in the adsorption process and the recovery rate in the whole detection process, realize the accurate quantification of sulfides in liquor, and solve the quantitative deviation problem caused by pre-processing loss in traditional external standard method; S5.3: Based on the detection signal parameters and calibration data, the actual concentration of sulfides in the sample is obtained by correction calculation formula, and the calculated The difference between the detection value of the blank sample and the calculated value is calculated to obtain the final actual concentration of the target sulfide in the sample, and the system background interference is further eliminated; Further, the step S6 comprises: S6.1: The quantitative results of each target sulfide of 3 parallel samples are arranged, and the average value and relative standard deviation are calculated, which is required to be less than or equal to 5%, otherwise re-detection, to ensure the repeatability of the results; S6.2: The detection data is summarized and compared with the standard to complete the over-limit determination and early warning report output of sulfides, based on the national standard for liquor safety, the limit value of each target sulfide is determined, when the average value is greater than the limit value, it is determined that the target sulfide is over-limit, and when the average value is less than or equal to the limit value, it is determined that the target sulfide is not over-limit; The over-limit sulfide generates an early warning report, which contains the name of the over-limit sulfide, the detection concentration, the limit value and the over-limit multiple information, and records the adsorption efficiency and recovery rate in the detection process, which provides the basis for subsequent tracing and cause analysis; Further, the step S7 comprises: S7.1: Multi-dimensional verification confirms the effectiveness of the method, through the standard addition recovery experiment, the sulfide standard with known concentration is added to the blank liquor sample, and the recovery rate is calculated after detection according to the method, which is required to be greater than 90%, to verify the accuracy of the method and ensure the reliability of the quantitative result; S7.2: Insert quality control samples to monitor the stability of the detection process, insert a medium concentration quality control sample every 10 samples, if the detection result of the quality control sample deviates from the standard value by more than the standard threshold, stop detection, recalibrate the system and then perform the experiment, and monitor the stability of the detection process in real time.
[0006] The technical effect and advantages of the method for detecting liquor by using the liquor gas chromatography analysis system of the present application are as follows: The present application realizes efficient capture and matrix purification of sulfides through scientific sample processing, provides a stable and reliable basis for detection through precise debugging and calibration of the special analysis system, optimizes separation conditions and detection methods to improve the separation effect of sulfides and other components and the detection ability of low-concentration components, eliminates interference through signal preprocessing technology to ensure the accuracy of the detection data, compensates for the loss of components in the detection process relying on the revised quantitative calculation model, realizes scientific judgment and over-limit early warning of the sulfide content through standard comparison and uncertainty analysis, and guarantees the repeatability and stability of the method through multi-dimensional verification and quality control, thereby providing strong technical support for liquor quality control and safety protection. BRIEF DESCRIPTION OF DRAWINGS
[0007] Figure 1 A method for detecting liquor by using the liquor gas chromatography analysis system of the present application is shown in the figure. DETAILED DESCRIPTION
[0008] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.
[0009] Embodiment 1, please refer to Figure 1 The method for detecting liquor by using the liquor gas chromatography analysis system of the present application is shown in the figure, and the method comprises: S1: Ensure sample representativeness through standardized collection process to avoid volatilization or deterioration of sulfides due to environmental factors, and innovative dynamic adsorption and thermal desorption coupling technology can efficiently capture trace sulfides in the sample while eliminating the interference of alcohol content and moisture matrix, the activated adsorption tube and purification column work together to realize enrichment and purification of target components, and provide high-purity samples for subsequent chromatographic analysis, thereby improving detection accuracy from the source; S2: Through system assembly and gas purification, the interference of impurities in the carrier gas and auxiliary gas on the detection is eliminated; the detector parameter debugging and baseline stability control ensure the sensitivity and stability of the signal response, the drawing of the calibration curve provides a standard basis for quantitative calculation, and the blank verification excludes the risk of system pollution, ensuring the reliability of the subsequent detection data; S3: Through the complementary characteristics of the dual-column series, the complete separation of sulfides and alcohol, ester interfering components in liquor is achieved; split injection and optimized column temperature program avoid chromatographic column overload, improve separation efficiency, high selectivity of the detector and signal acquisition synchronicity, precise capture of target sulfide characteristic signal, detection of the system cleaning prevents residual components from interfering with subsequent samples, ensuring the continuity and accuracy of the detection; S4: Baseline correction and abnormal peak rejection can eliminate the influence of instrument drift and random interference on the signal, smooth processing reduces noise while retaining the core information of the target peak, improving signal quality; characteristic peak identification through retention time and peak shape double judgment realizes the accurate specificity of target sulfide, selects reliable signal data for subsequent quantitative calculation, and ensures the rigor of the results; S5: Through the external standard method correction model to realize accurate quantification, introduce the correction coefficient of adsorption efficiency and recovery rate, compensate for the loss of components in pretreatment and detection; correlate sample peak area with standard parameters, combine key variables such as sampling and transfer volume, directly output sulfide concentration, parameter definition is clear and logic is rigorous, ensure the calculation process is traceable, effectively improve the accuracy and anti-interference ability of quantitative results; S6: Through comparison with national standards, combined with uncertainty evaluation, a scientific over-standard judgment logic is constructed to avoid misjudgment; a detailed warning report is generated for over-standard cases, clearly identifying the over-standard items and key parameters, providing direct evidence for liquor production quality control, and realizing the practical value transformation of detection results; S7: Precision and accuracy verification respectively confirm the method performance from the perspectives of repeatability and authenticity; the determination of detection limit and quantitative limit clarifies the applicable range of the method, meets the detection needs of trace sulfides, durability verification ensures that the method is stable and reliable when the parameters fluctuate, and the insertion of quality control samples monitors the detection process in real time, ensuring the quality and reliability of the overall detection data; The core of the present application is to solve the problems of large interference and low sensitivity in sulfide detection caused by complex liquor matrix through two innovative technologies of dynamic adsorption and thermal desorption coupled pretreatment, dual-column series and selective detector; the former can efficiently capture target sulfides and exclude interference from other components in liquor; the latter realizes precise separation and high-sensitivity detection of sulfides; through sample processing, instrument calibration, signal analysis and quantitative calculation of the system, it can accurately determine whether the sulfides in liquor exceed the standard, providing reliable data for liquor production quality control; Further, step S1 comprises: S1.1: The Baijiu sample acquisition process is to collect three samples of Baijiu under a constant temperature environment at 20 degrees Celsius, with each sample accurately taken to 10 milliliters. During the sampling process, the sample is avoided from being aerated to generate bubbles. At the same time, an adsorption tube filled with modified activated carbon and silica gel composite adsorbent is used. The adsorption tube is activated by nitrogen blowing for 30 minutes at 300 degrees Celsius in advance, cooled to room temperature, and sealed for standby to ensure that the adsorbent is free of impurities; S1.2: The Baijiu sample is coupled with dynamic adsorption and thermal desorption to obtain the target sulfide components that can be introduced into the chromatography system. The sample bottle and the adsorption tube are connected through a polytetrafluoroethylene pipeline. At the same time, the nitrogen carrier gas flow rate is set to 50 milliliters per minute, the adsorption temperature is controlled at 25 degrees Celsius, and the adsorption time is 20 minutes. The volatile sulfides in the sample are fully captured by the adsorbent, while the alcohol content and water content are excluded. On this basis, the adsorption tube is connected to the thermal desorption instrument. The desorption temperature is set to 250 degrees Celsius, the desorption time is 3 minutes, and the desorption gas flow rate is 80 milliliters per minute. The desorbed gas is passed through a purification column to remove high-boiling organic compounds, and the purification temperature is 80 degrees Celsius to ensure the single output of the target components; It needs to be explained that the purification column is a porous layer open column with polystyrene and divinylbenzene copolymer stationary phase; S1.3: The purified target sulfides are automatically transferred to the gas chromatography injection port through a six-way valve. The injection port temperature is maintained at 220 degrees Celsius to realize the lossless introduction of the sample; Further, step S2 includes: S2.1: Build a gas chromatography and thermal desorption instrument coupled system and complete the debugging and calibration. The chromatography column uses a double column tandem structure, and the detector selects a flame photometric detector. The detector and the chromatography column outlet are connected by a quartz capillary tube, and the connection is sealed without leakage; S2.2: The carrier gas is high-purity nitrogen, which is treated by a deoxidizing and dehydrating purifier before being connected to the system. The carrier gas column pressure is set to 0.12 MPa in constant pressure mode. The auxiliary gas is hydrogen and air, with a hydrogen flow rate of 40 milliliters per minute and an air flow rate of 400 milliliters per minute; S2.3: Start the FPD detector and set the detector temperature to 280 degrees Celsius, the photomultiplier tube voltage to 700 volts, and the sulfur filter wavelength to 394 nanometers. After ignition, stabilize for 30 minutes; S2.4: Establish a quantitative reference basis for sulfide detection. Prepare 5 groups of gradient concentration sulfide standard mixed solutions according to the method of step S1. After pretreatment, inject the system. Take the standard solution concentration as the abscissa and the corresponding peak area as the ordinate to draw the calibration curve of each target sulfide; It needs to be explained that the mixed solution contains hydrogen sulfide, methyl mercaptan, ethyl mercaptan, and carbon disulfide with concentrations of 0.01, 0.05, 0.10, 0.50, and 1.00 mg / L, respectively; Further, step S3 includes: S3.1: The pretreated target components are introduced into the chromatographic system through the six-way valve to realize automatic injection of the sample after thermal desorption. The injection mode is split injection, the split ratio is set to 10:1, and the injection time is 30 seconds to avoid overloading of the chromatographic column due to excessive injection volume; S3.2: Signal acquisition is completed after separation by double-column series. The initial column temperature is set to 35 degrees Celsius and maintained for 3 minutes. The temperature is raised to 80 degrees Celsius at a rate of 5 degrees Celsius per minute, maintained for 2 minutes, and then raised to 200 degrees Celsius at a rate of 15 degrees Celsius per minute, maintained for 5 minutes. Through the complementary action of the double-column series, the sulfides and alcohol and ester matrix components in the liquor are completely separated; S3.3: Based on the peak regularity of the standard, the switching time of the non-polar column and the polar column is set to ensure that the non-target components are intercepted by the non-polar column, and the target sulfides are further separated by the polar column and enter the detector; start the chromatographic workstation, set the signal acquisition frequency, and synchronize the acquisition time and the column temperature program, record the retention time, peak area and peak height data of each target sulfide; Further, step S4 includes: S4.1: The collected detection signal is preprocessed, and a polynomial fitting algorithm is used to correct the baseline of the collected original signal, covering the entire acquisition period, eliminating baseline drift caused by instrument drift, and selecting the corrected signal peaks, removing interference peaks with peak height lower than 3 times the baseline noise, and retaining target peaks with symmetrical peak shape; S4.2: Based on the retention time of each target sulfide in the calibration curve, combined with the peak shape characteristics, the smoothed signal peaks are qualitatively identified to determine the target sulfide corresponding to each peak, and the confirmation and identification of the target sulfide characteristic peaks are completed; S4.3: The preprocessed signal data retention time, peak area and peak shape parameters are stored in CSV format, and the detection date, instrument number and sample number information are recorded to ensure data storage and traceability; Further, step S5 includes: S5.1: Extract the peak area of each target sulfide from the preprocessed signal data, and record the standard concentration and standard peak area parameters in the calibration curve; S5.2: Use the external standard method to correct the model, introduce two correction coefficients of adsorption efficiency and recovery rate to compensate for the loss of components in the pretreatment and detection process, and improve the quantitative accuracy. The specific correction formula is: ; The concentration of the first target sulfide in the sample is obtained , wherein , and is the first target sulfide in the sample The detection peak area of the target sulfide was directly acquired by the chromatography workstation, reflecting the response intensity of the target component in the sample. For the first in the standard solution The concentration of the target sulfide, a known and definitive value used in preparing the standard, is used as the quantitative reference standard. This represents the transfer volume of the target component during thermal desorption. It is a set parameter of the thermal desorber to ensure that all the target component enters the chromatographic system. For the first in the standard solution The peak area of the target sulfide is the response value when the standard is detected, used to establish the correlation between concentration and response intensity. To determine the sample volume and ensure sample representativeness, For the adsorption tube to the first The adsorption efficiency of the target sulfide was determined by adsorption experiments using standard samples, and the loss due to incomplete capture of the target component during adsorption was corrected. For the detection method to the first The recovery rate of the target sulfides was measured by spiked recovery experiments, which corrected for the volatilization and residual loss of the target components in the entire detection process. The calculation formula is to eliminate the influence of matrix interference and operational errors on the quantitative results by correcting the adsorption efficiency in the adsorption process and the recovery rate of the entire detection process, so as to achieve accurate quantification of sulfides in liquor and solve the quantitative deviation problem caused by pretreatment loss in the traditional external standard method. S5.3: Based on the detection signal parameters and calibration data, the actual concentration of sulfides in the sample is obtained through a corrected calculation formula. The calculated concentration is then... The difference between the measured values and the blank sample values is calculated to obtain the final actual concentration of the target sulfide in the sample, further eliminating background interference from the system. Furthermore, step S6 includes: S6.1: Compile the quantitative results of each target sulfide from 3 parallel samples, calculate the average value and relative standard deviation. The relative standard deviation should be less than or equal to 5%. Otherwise, retest to ensure the repeatability of the results. S6.2: Summarize the test data and compare it with the standard to complete the determination of sulfide exceedance and output the early warning report. Based on the national standard for liquor safety, clarify the limit value of each target sulfide. When the average value is greater than the limit value, the target sulfide is determined to exceed the standard. When the average value is less than or equal to the limit value, the target sulfide is determined to not exceed the standard. Generate an early warning report for the sulfide that exceeds the standard. The early warning report includes the name of the sulfide that exceeds the standard, the detection concentration, the limit value, and the multiple of exceedance information. At the same time, record the adsorption efficiency and recovery rate during the detection process to provide a basis for subsequent traceability and cause analysis. Furthermore, step S7 includes: S7.1: Multi-dimensional verification confirms the validity of the method, through the standard addition recovery experiment, the sulfide standard with known concentration is added to the blank liquor sample, the recovery rate is calculated after detection according to the method, and the recovery rate is required to be greater than 90%, the accuracy of the method is verified, and the quantitative result is ensured to be reliable; S7.2: Inserting quality control samples to monitor the stability of the detection process, every 10 samples are detected, 1 medium concentration quality control sample is inserted, if the detection result of the quality control sample deviates from the standard value by more than the standard threshold, the detection is stopped, the system is recalibrated and then the experiment is carried out, and the stability of the detection process is monitored in real time; It needs to be explained that the concentration of the medium concentration is 100% of the limit value; the standard threshold is manually set and input; In this embodiment, the beneficial effects are that through the combination of innovative pretreatment and detection technology, efficient and accurate detection of sulfides in liquor is realized; the unique adsorption and thermal desorption coupling mode can fully capture volatile sulfides, effectively eliminate the interference of other matrixes in the liquor, ensure high-purity separation and lossless transfer of the target component, the design of double-column series connection and selective detector strengthens the separation effect of sulfides and complex matrixes, improves the selectivity and sensitivity of detection, and can accurately identify low-content target components; the signal preprocessing technology reduces the detection noise interference, and the quantitative calculation model combined with the introduction of correction coefficient greatly reduces the operation and system error, and improves the accuracy and reliability of the quantitative result; the perfect result determination and method verification system further guarantees the scientificity and stability of the detection result, and provides efficient and reliable technical support for the over-standard screening of sulfides in liquor.
[0010] For those skilled in the art, it is obvious that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application.
[0011] Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application. Any additional reference signs in the claims should not be considered as limiting the claims involved.
[0012] In addition, it is obvious that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. The plurality of units or devices stated in the system claims can also be implemented by one unit or device through software or hardware. The words first, second, etc. are used to indicate names, and do not mean any specific order.
[0013] Finally, it should be noted that the above examples are merely intended to illustrate the technical solutions of the present application and not to limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present application.
Claims
1. A method for detecting baijiu (Chinese white liquor) using a gas chromatography analysis system, characterized in that, The method includes: S1: Collect liquor samples and obtain target sulfide components that can be imported into the chromatographic system through dynamic adsorption and thermal desorption coupling treatment; S2: Build a gas chromatography-thermal desorption coupled system and complete debugging and calibration to establish a quantitative reference basis for sulfide detection; S3: The pretreated target component is introduced into the chromatographic system, and signal acquisition is completed after separation by dual-column tandem separation. S4: Preprocess the collected detection signals to identify and store the characteristic peaks of the target sulfide; S5: Based on the detection signal parameters and calibration data, the actual concentration of sulfides in the sample is obtained through a corrected calculation formula; S6: Summarize the test data and compare it with the standard to complete the determination of sulfide exceedance and output the early warning report; S7: Verify the effectiveness of the method through multi-dimensional validation, and insert quality control samples to monitor the stability of the testing process.
2. The method for detecting baijiu (Chinese liquor) using a gas chromatography analysis system according to claim 1, characterized in that, Step S1 includes: S1.1: Collect three samples of baijiu (Chinese liquor) under a constant temperature environment of 20 degrees Celsius. The sample volume of each sample is accurate to 10 ml. At the same time, use an adsorption tube filled with a composite adsorbent of modified activated carbon and silica gel. The adsorption tube is activated by purging nitrogen at 300 degrees Celsius for 30 minutes in advance, and then sealed for later use after cooling to 25 degrees Celsius. S1.2: Connect the sampling bottle to the adsorption tube via a PTFE tubing. Simultaneously set the nitrogen carrier gas flow rate to 50 mL / min, the adsorption temperature to 25°C, and the adsorption time to 20 minutes to ensure that volatile sulfur compounds in the sample are fully captured by the adsorbent and to eliminate interference from the alcohol content and moisture matrix. Then, connect the adsorption tube to a thermal desorption instrument, setting the desorption temperature to 250°C, the desorption time to 3 minutes, and the desorption gas flow rate to 80 mL / min. The desorbed gas is then purified by a purification column to remove high-boiling-point organic compounds at a purification temperature of 80°C. S1.3: The purified target sulfide is automatically transferred to the gas chromatograph injection port through a six-way valve, and the injection port temperature is maintained at 220 degrees Celsius.
3. The method for detecting baijiu (Chinese liquor) using a gas chromatography analysis system according to claim 1, characterized in that, Step S2 includes: S2.1: Set up a gas chromatograph and thermal desorption system. The chromatographic column adopts a dual-column tandem structure. The detector is a flame photometric detector. The detector is connected to the column outlet through a quartz capillary tube. S2.2: High-purity nitrogen is used as the carrier gas. After being treated by a deoxygenator and dehydrator, it is introduced into the system. The carrier gas column pressure is set to 0.12MPa, and the system is operated in constant pressure mode. The auxiliary gas is hydrogen and air. The hydrogen flow rate is 40 ml / min, and the air flow rate is 400 ml / min. S2.3: Start the FPD detector, set the detector temperature to 280 degrees Celsius, the photomultiplier tube voltage to 700 volts, the sulfur filter wavelength to 394 nanometers, and stabilize for 30 minutes after ignition; S2.4: Prepare five sets of sulfide standard mixed solutions with gradient concentrations, pre-treat them according to the method in step S1, and then inject them into the system. Plot the calibration curves of each target sulfide with the standard solution concentration as the abscissa and the corresponding peak area as the ordinate.
4. The method for detecting baijiu (Chinese liquor) using a gas chromatography analysis system according to claim 1, characterized in that, Step S3 includes: S3.1: Automatic sample injection after thermal desorption is achieved through a six-way valve. The injection method is split injection, the split ratio is set to 10:1, and the injection time is 30 seconds. S3.2: Set the initial column temperature to 35 degrees Celsius, hold for 3 minutes, increase the temperature to 80 degrees Celsius at a rate of 5 degrees Celsius per minute, hold for 2 minutes, and then increase the temperature to 200 degrees Celsius at a rate of 15 degrees Celsius per minute, hold for 5 minutes; S3.3: Based on the peak elution pattern of the standard, set the switching time between the non-polar column and the polar column. The target sulfide enters the detector after further separation by the polar column. Start the chromatography workstation, set the signal acquisition frequency, synchronize the acquisition time with the column temperature program, and record the retention time, peak area and peak height data of each target sulfide.
5. A method for detecting baijiu (Chinese liquor) using a baijiu gas chromatography analysis system according to claim 1, characterized in that, Step S4 includes: S4.1: The original acquired signal is baseline corrected using a polynomial fitting algorithm. The correction range covers the entire acquisition period. The corrected signal peaks are then screened to remove interference peaks with peak heights less than 3 times the baseline noise, while retaining the target peaks with symmetrical peak shapes. S4.2: Based on the retention time of each target sulfide in the calibration curve and combined with the peak shape characteristics, the smoothed signal peaks are qualitatively identified to determine the target sulfide corresponding to each peak. S4.3: Store the preprocessed signal data retention time, peak area, and peak shape parameters in CSV format, and record the detection date, instrument number, and sample number information.
6. The method for detecting baijiu (Chinese liquor) using a gas chromatography analysis system according to claim 1, characterized in that, Step S5 includes: S5.1: Extract the peak area corresponding to each target sulfide from the preprocessed signal data, and record the standard concentration and standard peak area parameters in the calibration curve. S5.2: The external standard method is used to correct the model, introducing two correction coefficients, adsorption efficiency and recovery rate, to compensate for component loss during pretreatment and detection. The specific correction formula is as follows: ； The first sample was obtained Concentration of the target sulfide ,in, For the first in the sample The peak areas of the target sulfides were obtained directly from the chromatographic workstation. For the first in the standard solution The concentration of the target sulfide, a known and definitive value used in preparing the standard. This represents the transfer volume of the target component during thermal desorption, and is a set parameter of the thermal desorption instrument. For the first in the standard solution The peak area of the target sulfide is the response value when detecting the standard. The sample volume is [the volume of the sample taken]. For the adsorption tube to the first The adsorption efficiency of the target sulfide was determined by adsorption experiments using standard samples. For the detection method to the first The recovery rates of the target sulfides were determined by spiked recovery experiments; S5.3: The calculated The difference between the measured values and the blank sample values is calculated to obtain the final actual concentration of the target sulfide in the sample.
7. The method for detecting baijiu (Chinese liquor) using a gas chromatography analysis system according to claim 1, characterized in that, Step S6 includes: S6.1: Compile the quantitative results of each target sulfide from 3 parallel samples, calculate the average value and relative standard deviation. The relative standard deviation should be less than or equal to 5%; otherwise, retest. S6.2: Based on the national standards for the safety of liquor, the limit values for each target sulfide are specified. If the average value is greater than the limit value, the target sulfide is judged to exceed the standard. If the average value is less than or equal to the limit value, the target sulfide is judged not to exceed the standard. An early warning report is generated for sulfides that exceed the standard. The early warning report includes the name of the sulfide that exceeds the standard, the detection concentration, the limit value, and the multiple of exceedance information. At the same time, the adsorption efficiency and recovery rate during the detection process are recorded.
8. The method for detecting baijiu (Chinese liquor) using a gas chromatography analysis system according to claim 1, characterized in that, Step S7 includes: S7.1: Through a spiked recovery experiment, a known concentration of sulfide standard is added to a blank liquor sample, and the recovery rate is calculated after detection according to this method. The recovery rate is required to be greater than 90% to verify the accuracy of the method. S7.2: For every 10 samples tested, insert one quality control sample of medium concentration. If the test result of the quality control sample deviates from the standard value by more than the standard threshold, stop the test, recalibrate the system, and then conduct the experiment again.