Method for detecting vinyl chloride in beverage

Abstract

The invention provides a method for detecting vinyl chloride in a beverage, which comprises the following steps: sampling, and adding a first volume of saturated sodium chloride solution into a sample to obtain a to-be-detected mixed solution; adding the to-be-detected mixed solution into a headspace bottle, heating to a first temperature, and balancing for a first time; detecting the mixed solution to be detected through a gas chromatograph-mass spectrometer; wherein the temperature rising conditions of the gas chromatograph-mass spectrometer are as follows: the initial temperature of 40 DEG C is maintained for 3 minutes; raising the temperature to 80 DEG C at the rate of 10 DEG C per minute, maintaining the temperature at 80 DEG C for 3 minutes, and raising the temperature to 120 DEG C at the rate of 5 DEG C per minute; and heating to 240 DEG C at the rate of 20 DEG C per minute, and maintaining for 2 minutes at the temperature of 240 DEG C. The content of vinyl chloride in the liquid is detected by a gas chromatograph-mass spectrometer, the detection is accurate, and the method has the advantages of excellent repeatability and reproducibility, simplicity and convenience in operation, high speed, easiness in obtaining used equipment and high generalizability.

Description

Technical Field

[0001] The present application relates to the technical field of analytical chemistry, and in particular to a method for detecting vinyl chloride in beverages. Background Art

[0002] Vinyl chloride, also known as vinyl chloride, has a chemical formula of CH2CHCl. ​​It is a type of halogenated hydrocarbon and is used in large quantities in industry as a monomer for the production of polyvinyl chloride (PVC). It is a colorless, toxic gas at room temperature, slightly soluble in water, and has an ether-like odor. Monomer vinyl chloride is a component contained in polyvinyl chloride resin (PVC) and its complexes. Vinyl chloride is a toxic substance, and liver cancer is related to long-term inhalation and exposure to vinyl chloride.

[0003] Vinyl chloride is rapidly absorbed after inhalation or oral exposure. After absorption, it can be rapidly and widely distributed in some tissues, such as the brain, liver, spleen, kidney, adipose tissue and muscle. The highest content is in the liver, followed by the kidney. When vinyl chloride is ingested at low concentrations, excretion is the main elimination route, and only a very small amount is discharged from the air in the original form. However, once metabolic saturation is reached, it is mainly exhaled in the original form and cannot be eliminated by other routes. Vinyl chloride is mutagenic and clastogenic in humans, and also has certain effects on reproduction and development. There is also evidence that vinyl chloride is carcinogenic to animals. Vinyl chloride is mainly used in the production of polyvinyl chloride. Vinyl chloride and polyvinyl chloride can be used as raw materials for plastics, rubber, paper, glass and the automotive industry. The migration of vinyl chloride monomer in polyvinyl chloride is a possible source of vinyl chloride in drinking water used in beverage production.

[0004] Currently, the detection methods for vinyl chloride are all aimed at food contact materials, but there are no relevant detection methods for vinyl chloride in drinking products such as water and beverages, and it is impossible to detect the amount of vinyl chloride migration in liquids. Summary of the invention

[0005] In view of the above problems, the present application is proposed to provide a method for detecting vinyl chloride in beverages that overcomes the above problems or at least partially solves the above problems, comprising:

[0006] A method for detecting vinyl chloride in beverages comprises the following steps:

[0007] Taking a sample, and adding a first volume of a saturated sodium chloride solution to the sample to obtain a mixed solution to be tested;

[0008] Adding the mixed solution to be detected into a headspace bottle and heating it to a first temperature for a first time;

[0009] The mixed liquid to be detected is detected by gas chromatography-mass spectrometry; wherein the heating conditions of the gas chromatography-mass spectrometry are: initially maintained at 40°C for 3 minutes; then heated to 80°C at a rate of 10°C per minute and maintained at 80°C for 3 minutes, then heated to 120°C at a rate of 5°C per minute; then heated to 240°C at a rate of 20°C per minute, and maintained at 240°C for 2 minutes.

[0010] Furthermore, the first volume is 3-5 mL.

[0011] Furthermore, the step of detecting the mixed liquid to be detected by gas chromatography-mass spectrometry uses a chromatographic column model of DB-624, 30.0m*1.40mm*0.25um.

[0012] Furthermore, it also includes:

[0013] Prepare vinyl chloride standard solution;

[0014] Determining the vinyl chloride standard solution and determining a standard curve;

[0015] The test result is determined according to the standard curve.

[0016] Furthermore, the linear range of the standard curve is 1-60 μg / L.

[0017] Furthermore, the first temperature is 75-85°C.

[0018] Furthermore, the first time is 20-25 minutes.

[0019] Furthermore, the injection port temperature of the gas chromatography-mass spectrometry instrument is 220°C.

[0020] Furthermore, the ion source temperature of the gas chromatography-mass spectrometry instrument is 230°C.

[0021] Furthermore, the method also includes performing a spike recovery test on the test object to determine the spike recovery rate.

[0022] This application has the following advantages:

[0023] In the embodiments of the present application, there is no detection scheme for vinyl chloride in beverages in the prior art, which fills the gap in the prior art for the detection of vinyl chloride in liquid beverages such as drinking water and beverages. The present application provides a method for detecting vinyl chloride in beverages, including the steps of: taking samples, and adding a first volume of saturated sodium chloride solution to the sample to obtain a mixed solution to be detected; adding the mixed solution to be detected into a headspace bottle and heating it to a first temperature for equilibrium for a first time; detecting the mixed solution to be detected by a gas chromatograph-mass spectrometer; wherein the heating conditions of the gas chromatograph-mass spectrometer are: initially maintaining 40°C for 3 minutes; then heating to 80°C at a rate of 10°C per minute and maintaining at 80°C for 3 minutes, then heating to 120°C at a rate of 5°C per minute; then heating to 240°C at a rate of 20°C per minute and maintaining at 240°C for 2 minutes, and detecting the content of vinyl chloride in the liquid by a gas chromatograph-mass spectrometer, accurately measuring and detecting, meeting the requirements of customers with such detection needs. At the same time, the headspace gas chromatography-mass spectrometry method has excellent repeatability and reproducibility, is easy to operate, fast, and the equipment used is easy to obtain. It is highly scalable and can regulate the use of such substances to avoid risks in social production. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the description of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0025] Figure 1 This is a flow chart of the steps of a method for detecting vinyl chloride in beverages provided in one embodiment of the present application;

[0026] Figure 2 This is an operation flow chart of a method for detecting vinyl chloride in beverages provided in one embodiment of the present application;

[0027] Figure 3 This is a standard curve diagram of a method for detecting vinyl chloride in beverages provided in one embodiment of the present application;

[0028] Figure 4 It is a chromatogram of a standard curve of a method for detecting vinyl chloride in beverages provided in an embodiment of the present application at a concentration point of 1 μg / L;

[0029] Figure 5 It is a chromatogram of a standard curve of a method for detecting vinyl chloride in beverages provided in an embodiment of the present application at a concentration point of 2 μg / L;

[0030] Figure 6It is a chromatogram of a standard curve of a method for detecting vinyl chloride in beverages provided in an embodiment of the present application at a concentration point of 5 μg / L;

[0031] Figure 7 It is a chromatogram of a standard curve of a method for detecting vinyl chloride in beverages provided in an embodiment of the present application at a concentration point of 10 μg / L;

[0032] Figure 8 It is a chromatogram of a standard curve of a method for detecting vinyl chloride in beverages provided in an embodiment of the present application at a concentration point of 60 μg / L;

[0033] Fig. 9 This is a method for detecting vinyl chloride in beverages provided in one embodiment of the present application. A vinyl chloride spiked spectrum of a beverage sample A;

[0034] Fig.10 A method for detecting vinyl chloride in beverages provided in one embodiment of the present application is a vinyl chloride spectrum of a beverage sample B;

[0035] Fig.11 A method for detecting vinyl chloride in beverages provided in one embodiment of the present application is a spiked spectrum of vinyl chloride in a beverage sample. DETAILED DESCRIPTION

[0036] In order to make the objects, features and advantages of the present application more obvious and understandable, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0037] The inventors have found through analysis of the prior art that vinyl chloride is a substance that is toxic to the human body. Currently, the detection methods for vinyl chloride are all for food contact materials, but there are no relevant detection methods for vinyl chloride for drinking products such as water and beverages, and it is impossible to detect the migration amount of vinyl chloride in liquids.

[0038] Reference Figure 1-2 , showing a step flow chart and an operation flow chart of a method for detecting Acid Red 92 in cosmetics provided in one embodiment of the present application:

[0039] The method comprises:

[0040] S110, taking a sample, and adding a first volume of a saturated sodium chloride solution to the sample to obtain a mixed solution to be detected;

[0041] S120, adding the mixed solution to be detected into a headspace bottle and heating it to a first temperature for a first time;

[0042] S130. Detecting the mixed liquid to be detected by gas chromatography-mass spectrometry; wherein the heating conditions of the gas chromatography-mass spectrometry are as follows: initially maintaining at 40°C for 3 minutes; then increasing the temperature to 80°C at a rate of 10°C per minute and maintaining at 80°C for 3 minutes, then increasing the temperature to 120°C at a rate of 5°C per minute; then increasing the temperature to 240°C at a rate of 20°C per minute and maintaining at 240°C for 2 minutes.

[0043] In the embodiments of the present application, there is no detection scheme for vinyl chloride in beverages in the prior art, which fills the gap in the prior art for the detection of vinyl chloride in liquid beverages such as drinking water and beverages. The present application provides a method for detecting vinyl chloride in beverages, including the steps of: taking samples, and adding a first volume of saturated sodium chloride solution to the sample to obtain a mixed solution to be detected; adding the mixed solution to be detected into a headspace bottle and heating it to a first temperature for equilibrium for a first time; detecting the mixed solution to be detected by a gas chromatograph-mass spectrometer; wherein the heating conditions of the gas chromatograph-mass spectrometer are: initially maintaining 40°C for 3 minutes; then heating to 80°C at a rate of 10°C per minute and maintaining at 80°C for 3 minutes, then heating to 120°C at a rate of 5°C per minute; then heating to 240°C at a rate of 20°C per minute and maintaining at 240°C for 2 minutes, and detecting the content of vinyl chloride in the liquid by a gas chromatograph-mass spectrometer, accurately measuring and detecting, meeting the requirements of customers with such detection needs. At the same time, the headspace gas chromatography-mass spectrometry method has excellent repeatability and reproducibility, is easy to operate, fast, and the equipment used is easy to obtain. It is highly scalable and can regulate the use of such substances to avoid risks in social production.

[0044] Next, a method for detecting vinyl chloride in a beverage in this exemplary embodiment will be further described.

[0045] As described in step S110, a sample is taken, and a first volume of saturated sodium chloride solution is added to the sample to obtain a mixed solution to be detected.

[0046] In one embodiment of the present application, the first volume is 3-5 mL / g.

[0047] It should be noted that the mixture can be weighed directly in the headspace bottle without transferring the mixed solution to be tested.

[0048] In a specific implementation, 1.0 g of sample was weighed and 4 mL of saturated sodium chloride was added.

[0049] As described in step S120, the mixed solution to be detected is added into a headspace bottle and heated to a first temperature for a first equilibration time.

[0050] In one embodiment of the present application, the first temperature is 75-85°C.

[0051] In one embodiment of the present application, the first time is 20-25 minutes.

[0052] In a specific implementation, the mixed solution to be detected is placed in a headspace bottle, and the headspace bottle is equilibrated at 80° C. for 20 minutes before sampling and detection.

[0053] As described in step S130, the mixed liquid to be detected is detected by a gas chromatography-mass spectrometer; wherein the heating conditions of the gas chromatography-mass spectrometer are: initially maintained at 40°C for 3 minutes; then heated to 80°C at a rate of 10°C per minute and maintained at 80°C for 3 minutes, then heated to 120°C at a rate of 5°C per minute; then heated to 240°C at a rate of 20°C per minute, and maintained at 240°C for 2 minutes.

[0054] In one embodiment of the present invention, the following description can be combined to further illustrate the specific process of step S130 of "detecting the mixed liquid to be detected by gas chromatography-mass spectrometry; wherein the heating conditions of the gas chromatography-mass spectrometry are: initially maintaining 40°C for 3 minutes; then heating to 80°C at a rate of 10°C per minute and maintaining at 80°C for 3 minutes, then heating to 120°C at a rate of 5°C per minute; then heating to 240°C at a rate of 20°C per minute, and maintaining at 240°C for 2 minutes".

[0055] The testing instrument parameters are:

[0056] Instrument: GCMS;

[0057] Chromatographic column: Agilent DB-624 30.0m*1.40mm*0.25um;

[0058] Injection mode: split;

[0059] Injection volume: 1uL;

[0060] Inlet temperature: 220°C;

[0061] Carrier gas: high purity helium;

[0062] Carrier gas flow rate: 2.87;

[0063] Heating program: initial temperature 40℃, hold for 3min; increase to 80℃ at 10℃ / min, hold for 3min; increase to 120℃ at 5℃ / min, increase to 240℃ at 20℃ / min, hold for 2min;

[0064] Ion source temperature: 230°C;

[0065] Interface temperature: 220℃;

[0066] Target substance: Vinyl chloride; English: Vinyl chloride; CAS No.: 75-01-4;

[0067] Retention time: 4.582min;

[0068] Quantitative ion: 63m / z;

[0069] Reference examples: 62m / z, 64m / z.

[0070] refer to Figure 3-8 , which is the chromatogram of each concentration point of the standard curve of vinyl chloride in beverages measured by gas chromatography-mass spectrometry and the linearity of vinyl chloride. The linear range of the standard curve and the retention time of the target substance of vinyl chloride are shown in Table 1:

[0071]

[0072] Table 1

[0073] Figure 9-10 The chromatograms are of two different brands of sample beverages detected by gas chromatography-mass spectrometry. The above method can be used to detect the content of vinyl chloride in the beverage samples. This scheme has good repeatability and reproducibility and is quantitatively accurate.

[0074] Fig.11 This is a chromatogram of a spiked test on a beverage sample. The recovery rate of the spiked recovery test on the beverage sample is within a satisfactory range of 60%-120%. As shown in the spectrum, this method can achieve high-efficiency separation and stable baseline.

[0075] It can be seen from the above embodiments that the present solution uses gas chromatography-mass spectrometry to detect the content of vinyl chloride in beverages and other drinks, has excellent repeatability and reproducibility, is easy to operate, has a high speed, and the equipment used is easy to obtain, and is highly scalable.

[0076] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0077] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0078] The above is a detailed introduction to the method for detecting vinyl chloride in beverages provided by the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for detecting vinyl chloride in beverages, characterized in that: Includes steps: Taking a sample, and adding a first volume of a saturated sodium chloride solution to the sample to obtain a mixed solution to be tested; Adding the mixed solution to be detected into a headspace bottle and heating it to a first temperature for a first time; The mixed liquid to be detected is detected by gas chromatography-mass spectrometry; wherein the heating conditions of the gas chromatography-mass spectrometry are: initially maintained at 40°C for 3 minutes; then heated to 80°C at a rate of 10°C per minute and maintained at 80°C for 3 minutes, then heated to 120°C at a rate of 5°C per minute; then heated to 240°C at a rate of 20°C per minute, and maintained at 240°C for 2 minutes.

2. The detection method according to claim 1, characterized in that: The first volume is 3-5 mL / g.

3. The detection method according to claim 1, characterized in that: The step of detecting the mixed liquid to be detected by gas chromatography-mass spectrometry uses a chromatographic column model of DB-624, 30.0m*1.40mm*0.25um.

4. The detection method according to claim 1, characterized in that: Also includes: Prepare vinyl chloride standard solution; Determining the vinyl chloride standard solution and determining a standard curve; The test result is determined according to the standard curve.

5. The detection method according to claim 4, characterized in that: The linear range of the standard curve is 1-60 μg / L.

6. The detection method according to claim 1, characterized in that: The first temperature is 75-85°C.

7. The detection method according to claim 1, characterized in that: The first time is 20-25 minutes.

8. The detection method according to claim 1, characterized in that: The injection port temperature of the gas chromatography-mass spectrometry instrument is 220°C.

9. The detection method according to claim 1, characterized in that: The ion source temperature of the gas chromatography-mass spectrometry instrument is 230°C.

10. The detection method according to claim 1, characterized in that: It also includes performing a spike recovery test on the test to determine the spike recovery rate.

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