Method for identifying characteristic flavor of Maotai wine

Abstract

The invention relates to the field of analysis and detection, and particularly discloses a method for identifying characteristic flavor of Maotai wine. Comprising soy sauce wine component detection and characteristic flavor data analysis. The method comprises the following steps: diluting a to-be-detected sauced wine finished product by using a saturated saline solution, adding a mixed internal standard, directly carrying out quantitative detection on the to-be-detected sauced wine by using a proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS), and carrying out statistical analysis on component data of characteristic flavor in the sauced wine detected by the PTR-TOF by using a principal component analysis PCA module of Pirouette statistical analysis software; and based on a PCA result, different characteristic flavors of the Maotai wine are obtained through Wehn analysis. The detection method is rapid and efficient, multiple types of characteristic flavors are detected, quantification is accurate, and the method can be applied to identification of different sauced wines on the premise of certain data.

Description

Technical Field

[0001] The present invention relates to the field of analysis and detection, and more specifically, to a method for identifying the characteristic flavor of sauce-flavored liquor. Background Art

[0002] Maotai-flavor liquor (Maotai-flavor liquor) is one of the five major flavor types of Chinese liquor. Maotai-flavor liquor represented by Guizhou Moutai, Lai Mao, Fujian Shuanglong Xizhu Liquor, etc. belongs to the Daqu liquor category. Its style characteristics are prominent Maotai aroma, elegant and delicate, mellow body, and long-lasting fragrance, and it is deeply loved by people.

[0003] The brewing process of Maotai-flavor liquor is unique and subject to numerous influencing factors. The raw materials used in fermentation, the koji (dice yeast), the temperature and humidity during fermentation, and local microorganisms all significantly influence the development of the characteristic flavor. Furthermore, due to the wide variety of aromas in Maotai-flavor liquor, many factors influence its quality. Due to the significant price differences between different grades of Maotai-flavor liquor, some products may be sold as inferior or counterfeit. Existing liquor ratings rely primarily on manual evaluation, which is not only time-consuming and labor-intensive, but also subject to subjective factors. Therefore, identifying the characteristic flavors of different Maotai-flavor liquors is particularly important.

[0004] CN117805290A discloses a gas chromatography method for detecting the aroma components of liquor. By quantifying each aroma component, corresponding fingerprint detection methods and quality control standards are established. However, due to the complexity of aroma components, some aromas are unavailable as standard. Furthermore, some aromas have poor high-temperature stability or low concentrations, making them difficult to detect or calibrate in gas chromatography.

[0005] CN116773704A discloses a method for analyzing aroma components in empty liquor cups, using HS-SPME combined with GC-MS to analyze aroma components in empty liquor cups. GC-MS has high sensitivity and can detect even low levels of aroma, but this method cannot address the high-temperature stability of some aromas. Due to the high bombardment energy of GC-MS, aroma fragmentation is complex, which complicates the mass spectrum and may result in some aroma component detection results being unable to be compared within the database. Furthermore, due to the complexity of aroma components, standard samples for some aromas are unavailable, making it impossible to quantify aroma during the winemaking process and, naturally, to identify characteristic flavors. Summary of the Invention

[0006] To solve the above problems, the present invention discloses a method for identifying characteristic flavors of sauce-flavored liquor. The method is fast and efficient, can detect a wide variety of characteristic flavors, and is quantitatively accurate, and can be used to identify different sauce-flavored liquor products.

[0007] The present invention discloses a method for detecting the components of sauce-flavored liquor, comprising detecting the components of the liquor and analyzing characteristic flavor data. The detection of the components of the liquor utilizes PTR-TOF-MS, and a mixed internal standard is selected for auxiliary quantification of different sauce-flavored liquor products, thereby obtaining component data of the characteristic flavors of the sauce-flavored liquor. The characteristic flavor data analysis statistically analyzes the component data of the characteristic flavors of the sauce-flavored liquor to obtain the characteristic flavors of different sauce-flavored liquor products.

[0008] Furthermore, the different sauce-flavored liquor products include sauce-flavored liquor products of different brands or different regions, or different finished products of the same brand of sauce-flavored liquor.

[0009] The specific steps include:

[0010] Step 1. Accurately weigh 10 g of the finished sauce wine to be tested, add 0.1 g of mixed internal standard and 89.9 g of saturated salt water, and mix evenly to obtain a sauce wine dilution; accurately weigh 10 g of the sauce wine dilution in a 60 mL clean and dry headspace bottle, seal it, and set a constant temperature for a period of time to allow the volatile substances above the liquid surface of the headspace bottle to reach equilibrium;

[0011] Step 2: Connect the headspace bottle containing the sauce wine dilution to the inlet of the PTR-TOF-MS to allow the volatile substances to drift into the PTR-TOF-MS for detection. Scan each sample 5 times continuously, and take the average value of the mass spectrum data as the test value;

[0012] Step 3: Seal the headspace bottle containing 10g of saturated salt water and keep it at a constant temperature for a period of time. Connect the headspace bottle to the injection port of the PTR-TOF-MS. Set the parameters in the same way as in step 2. Scan the saturated salt water 5 times and take the average value of the mass spectrum data as the blank value. Subtract the blank value from the sample test value to obtain the average value of the sample mass spectrum data. Use the internal standard response value and the content ratio of the internal standard in the sample mass spectrum data as the quantitative basis to correct the content of similar characteristic compounds, thereby calculating the content of each characteristic flavor in the sauce wine.

[0013] Step 4: Characteristic flavor data analysis.

[0014] Preferably, the mixed internal standard is tert-butyl alcohol-d1 (CAS No.: 3972-25-6, molecular formula (CH3)3COD), ethyl acetoacetate-1,3-C2 (CAS No.: 77504-74-6, molecular formula 13 CH3CO 13 CH2COOCH2CH3), d5-ethyl hexanoate (CAS No. 1082581-90-5, molecular formula C8H 11 D5O2), diethyl malonate-d2 (CAS No. 4303-49-5, molecular formula C7H 10D2O4), benzaldehyde-α-d1 (CAS No.: 3592-47-0, molecular formula C6H5CDO); the mixed internal standard is calculated by weight, accounting for 96wt% of tert-butyl alcohol-d1, and the remaining internal standards each account for 1wt%, and the mixed internal standard is obtained after mixing evenly;

[0015] Preferably, the constant temperature is 50°C;

[0016] Preferably, the volatiles equilibration time is 30 minutes;

[0017] Preferably, the instrument conditions of the PTR-TOF-MS are set as follows: drift tube voltage 500-600V, drift tube temperature 60-70°C, drift tube pressure 125-250Pa; electric field strength 120-150Td; gas flow in the drift tube 10-30mL / min; injection time 30 seconds; mass scan range m / z = 10-700; each sample is measured for 30 seconds at an acquisition rate of one TIC spectrum per second, scanned continuously 5 times, and the average value is taken.

[0018] The present invention also discloses a data analysis method for the characteristic flavor of sauce-flavored liquor, which is described as follows: the principal component analysis (PCA) module of Pirouette statistical analysis software is used to perform statistical analysis on the component data of the characteristic flavor in sauce-flavored liquor detected by PTR-TOF; and based on the results of PCA, the characteristic flavors of different sauce-flavored liquors are obtained through Wayne analysis.

[0019] The beneficial effects of the present invention are as follows: the present invention uses a highly sensitive PTR-TOF-MS, which can be qualitatively determined without calibration, selects a mixed internal standard to be added to the system to assist in quantitative determination, measures a large number of characteristic flavor substances, and combines the PCA module of the Pirouette statistical analysis software to perform statistical analysis on the component data of the characteristic flavors in sauce-flavored liquor detected by PTR-TOF; and based on the analysis results of the PCA module, uses Wayne analysis to identify the characteristic flavors of different sauce-flavored liquors. The details are as follows:

[0020] The PTR-TOF-MS described in this invention uses a soft ionization technique, which allows the positively charged protons of volatile organic compounds to appear almost exclusively as molecular ion peaks in the time-of-flight mass spectrum. This allows for automated mass-to-charge ratio analysis and inference of molecular structure, without the need for calibration and with high accuracy. PTR-TOF-MS has high sensitivity and can detect trace amounts of volatile compounds, enabling the detection of aroma components in sauce-flavored liquor and the exploration of their synergistic effects.

[0021] 2. While the PTR-TOF-MS method described in the present invention is highly sensitive and provides accurate qualitative analysis, it is difficult to accurately quantify trace substances. Based on the varying volatility of various characteristic flavor compounds in sauce-flavored liquor, the present invention selects a mixed internal standard, calibrates the ionization efficiency, and achieves accurate quantitative analysis, facilitating subsequent data analysis.

[0022] 3. The present invention uses saturated salt water to dilute the sauce-flavored liquor, thereby reducing the ethanol concentration in the sauce-flavored liquor and lowering the ethanol partial pressure; the saturated salt water also reduces the water vapor partial pressure, and the proportion of water vapor in the headspace bottle is lower, which is beneficial to increase the proportion of volatile substances in the headspace bottle and improve the detection sensitivity.

[0023] If salt is added directly during pretreatment, the final concentration of salt in different sauce-flavored liquors may be different, making it impossible to ensure that the salt reduces the water vapor partial pressure consistently. At the same time, since the ethanol and aroma concentrations in the sauce-flavored liquors are too high, a certain degree of dilution is required. Therefore, using saturated salt water is both convenient and accurate.

[0024] 4. The present invention uses the PCA module of the Pirouette statistical analysis software to perform statistical analysis on the component data of the characteristic flavor in the sauce-flavored liquor detected by PTR-TOF; and based on the analysis results of the PCA module, the characteristic flavors of different sauce-flavored liquors are identified through Wayne analysis. This method is fast and accurate, and the characteristic flavors detected are diverse and quantitatively accurate, which is conducive to identifying different sauce-flavored liquors and improving the recognizability of sauce-flavored liquor brands or regions.

[0025] Figures in the specification

[0026] Figure 1 This is a VIP picture of the volatile aroma of sauce-flavored liquor in the four sauce-flavored liquor producing areas of Guizhou, Sichuan, Fujian and Guangxi.

[0027] Figure 2 This is the PCA scatter plot of the volatile aroma of sauce-flavored liquor in the four sauce-flavored liquor producing areas of Guizhou, Sichuan, Fujian and Guangxi.

[0028] Figure 3 This is a Venn diagram of volatile substances in sauce-flavored liquor from the four sauce-flavored liquor producing areas of Guizhou, Sichuan, Fujian and Guangxi. DETAILED DESCRIPTION

[0029] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0030] If the specific conditions are not specified in the examples, the experiments were carried out under conventional conditions or those recommended by the manufacturer. All reagents or instruments used, if the manufacturer is not specified, are commercially available conventional products.

[0031] Example 1

[0032] A method for detecting the ingredients of sauce-flavored liquor is described as follows:

[0033] Step 1. Accurately weigh 10 g of the finished sauce wine, add 0.1 g of the mixed internal standard and 89.9 g of saturated salt water, and mix well to obtain a sauce wine dilution; accurately weigh 10 g of the sauce wine dilution in a 60 mL clean and dry headspace bottle, seal it, and equilibrate it at 50 ° C for 30 minutes to allow the volatile substances above the liquid surface of the headspace bottle to reach equilibrium;

[0034] Step 2. Connect the headspace bottle containing the sauce wine dilution to the injection port of the PTR-TOF-MS, so that its volatile substances drift into the PTR-TOF-MS for detection; the instrument conditions of the PTR-TOF-MS are set as follows: drift tube voltage 600V, drift tube temperature 60°C, drift tube pressure 125Pa; electric field strength 140Td; gas flow rate in the drift tube 25mL / min; injection time 30 seconds; mass scanning range m / z = 10-700; each sample is measured for 30 seconds at an acquisition rate of one TIC spectrum per second, each sample is scanned continuously 5 times, and the average value of the mass spectrum data is taken as the test value;

[0035] Step 3. Seal the headspace bottle containing 10g of saturated salt water and equilibrate at 50°C for 30 minutes. Connect the headspace bottle to the inlet of the PTR-TOF-MS. Set the parameters the same as in Step 2. Scan the saturated salt water 5 times and take the average value of the mass spectrum data as the blank value. Subtract the blank value from the sample test value to obtain the average value of the sample mass spectrum data. Use the internal standard response value and the content ratio of the internal standard in the sample mass spectrum data as the quantitative basis to correct the content of similar characteristic compounds, thereby calculating the content of each characteristic flavor in the sauce-flavored liquor.

[0036] Examples 2-7

[0037] The steps and methods of Examples 2-7 are the same as those of Example 1, except that the finished sauce-flavored liquor 1 in Example 1 is replaced by the typical finished sauce-flavored liquor to be tested shown in Table 1.

[0038] Table 1. Marking, origin and brand of finished sauce-flavored liquors tested in Examples 1-7

[0039]

[0040]

[0041] Example 8

[0042] The sauce-flavor liquor component data obtained from the sauce-flavor liquor 1-7 in the above examples 1-7 obtained a total of about 300 volatile characteristic aromas, and 88 substances that contribute to the sauce-flavor liquor in different production areas were confirmed with an abundance value (VIP value) greater than 1. The VIP value of each substance is listed in Figure 1 It can be clearly seen that the aroma types of the seven sauce-flavored liquor products are different.

[0043] The sauce wine component data obtained from the sauce wine 1-7 in the above examples 1-7 were statistically analyzed using Pirouette statistical analysis software, and the PCA module was selected to perform statistical analysis on the components of the characteristic flavors of the sauce wines from the four production areas. The results of the main characteristic flavor components are as follows: Figure 2 As shown in the figure, the characteristic flavors of the four production areas of Guizhou, Sichuan, Fujian and Guangxi are clearly distinguished. The clustering degree of different samples from Guizhou and Fujian is relatively high, indicating that the sauce-flavor liquors produced in the same production area are relatively similar. Figure 1 The conclusions are consistent.

[0044] from Figure 2 It can be seen that the aroma components of the four production areas not only overlap but also have their own characteristic flavors. There are 46 common aromas, 19 characteristic aromas of Guizhou regional sauce wine, 3 characteristic aromas of Sichuan regional sauce wine, 9 characteristic aromas of Fujian regional sauce wine, and 18 characteristic aromas of Guangxi regional sauce wine. Based on the characteristic flavor data obtained from sauce wine 1-7 in Examples 1-7, the characteristic flavors of the sauce wine 1-7 were listed in the table below through Wayne analysis. Figure 3 .

[0045] In summary, from the analysis of the above embodiments 1-8, it can be seen that the method for identifying the characteristic flavor of sauce-flavored liquor according to the present invention can identify the types of sauce-flavored liquor from different production areas on the premise of accumulating certain data.

[0046] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention should fall within the scope of the present invention.

Claims

1. A method for identifying the characteristic flavor of sauce-flavored liquor, characterized in that: It includes the detection of sauce-flavored liquor ingredients and the analysis of characteristic flavor data; the detection of sauce-flavored liquor ingredients uses PTR-TOF-MS, and mixed internal standards are selected to assist in quantification of different sauce-flavored liquor products, thereby obtaining the component data of characteristic flavors in sauce-flavored liquor; The characteristic flavor data analysis is to perform statistical analysis on the component data of the characteristic flavor in sauce-flavored liquor, thereby obtaining the characteristic flavor of different sauce-flavored liquor products.

2. The method for identifying the characteristic flavor of sauce-flavored liquor according to claim 1, characterized in that: The different sauce-flavored liquor products include sauce-flavored liquor products of different brands or different regions, or different finished products of the same brand of sauce-flavored liquor.

3. The method for identifying the characteristic flavor of sauce-flavored liquor according to claim 1, characterized in that: The steps include: Step 1. Sample pretreatment: Accurately weigh 10 g of the finished sauce wine to be tested, add 0.1 g of mixed internal standard and 89.9 g of saturated salt water, and mix well to obtain a sauce wine dilution; accurately weigh 10 g of the sauce wine dilution in a 60 mL clean and dry headspace bottle, seal it, and set a constant temperature until the volatile substances above the liquid surface of the headspace bottle reach equilibrium; Step 2: Detection of sauce wine ingredients: (1) The headspace bottle containing the sauce wine dilution was connected to the injection port of the PTR-TOF-MS, so that the volatile substances drifted into the PTR-TOF-MS for detection. Each sample was scanned 5 times continuously, and the average value of the mass spectrum data was taken as the sample test value; (2) Seal the headspace bottle containing 10 g of saturated saline and keep it at a constant temperature until equilibrium is reached. Connect the headspace bottle to the injection port of the PTR-TOF-MS, scan the saturated saline five times, and take the average value of the mass spectrum data as the blank value; (3) Subtracting the blank value from the sample test value to obtain the average value of the sample mass spectrometry data; using the internal standard response value in the sample mass spectrometry data and the ratio of the internal standard content as a quantitative basis, calculate the content of the characteristic flavor in the sauce wine; (4) Characteristic flavor data analysis.

4. The method for identifying the characteristic flavor of sauce-flavored liquor according to claim 3, characterized in that: The characteristic flavor data analysis includes the following steps: using the principal component analysis (PCA) module of Pirouette statistical analysis software to perform statistical analysis on the component data of the characteristic flavor in the sauce-flavored liquor detected by PTR-TOF; and based on the results of PCA, obtaining the characteristic flavors of different sauce-flavored liquor products through Wayne analysis, thereby identifying different sauce-flavored liquor products.

5. The method for identifying the characteristic flavor of sauce-flavored liquor according to claim 1 or 3, characterized in that: The mixed internal standard is a composition of tert-butanol-d1, ethyl acetoacetate-1,3-C2, ethyl hexanoate-d5, diethyl malonate-d2 and benzaldehyde-α-d1; the mixed internal standard is calculated by weight, tert-butanol-d1 accounts for 96wt%, and the remaining internal standards each account for 1wt%, and the mixed internal standard is obtained by uniformly mixing all the internal standards.

6. The method for identifying the characteristic flavor of sauce-flavored liquor according to claim 3, characterized in that: The constant temperature in step 1 is 50°C.

7. The method for identifying the characteristic flavor of sauce-flavored liquor according to claim 3, characterized in that: The equilibration time in step 1 and step 2 was 30 minutes.

8. The method for identifying the characteristic flavor of sauce-flavored liquor according to claim 1 or 3, characterized in that: The instrument conditions of the PTR-TOF-MS were set as follows: drift tube voltage 500-600 V, drift tube temperature 60-70° C., drift tube pressure 125-250 Pa; electric field strength 120-150 Td; gas flow rate in the drift tube 10-30 mL / min; injection time 30 seconds; mass scan range m / z = 10-700; each sample was measured for 30 seconds at an acquisition rate of one TIC spectrum per second, scanned continuously five times, and the average value was taken.

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