CN111307927A - Rapid screening method for abnormal elements in white spirit - Google Patents

Abstract

The invention discloses a method for rapidly screening abnormal elements in white spirit, which belongs to the technical field of chemical analysis and detection and comprises the following steps: and respectively carrying out full-scan detection on the standard wine sample and the abnormal wine sample by adopting ICP-MS, and comparing two ICP-MS spectrograms to judge abnormal elements in the abnormal wine sample. The screening of the method of the invention completely avoids the pollution risk of elements in the white spirit, and is particularly suitable for searching reasons of abnormal white spirit (turbidity, precipitation, obvious color, peculiar smell and the like) so as to control the quality of the white spirit.

Description

Rapid screening method for abnormal elements in liquor

technical field

The invention belongs to the technical field of chemical analysis and detection, and in particular relates to a rapid screening method for abnormal elements in liquor.

Background technique

Liquor is obtained by fermenting and distilling one or more kinds of grains. It is possible to introduce a variety of trace and trace elements in various stages of production, which can not be ignored and affect the quality of liquor. On the one hand, lead Pb, manganese Mn, cadmium Cd, arsenic As, barium Ba and other heavy metals directly affect human health, and the content of lead Pb is listed as a health indicator of the national standard of liquor. On the other hand, the content ratio of various elements also directly affects the sensory quality of liquor: an appropriate amount of metal elements can reduce the irritation of the wine, make the wine taste soft, and improve the quality of the liquor; an inappropriate amount of metal elements may make the liquor appear Salty, bitter, astringent, iron smell and other odors, or coloring liquor (such as iron Fe, manganese Mn, etc.), appearing turbid precipitation (such as calcium Ca, magnesium Mg, barium Ba, etc.), reducing the quality of liquor. It can be seen that the screening of various elements is an essential and important link for the control of liquor quality.

Inductively coupled plasma mass spectrometry (ICP-MS) is an analytical technique that combines ICP and MS. In ICP-MS, ICP is an "ion source", which utilizes a high-frequency radio frequency signal of strong power applied on an inductive coil to form a high-temperature plasma inside the coil, and uses the push of gas to ensure the balance and continuous ionization of the plasma ; High temperature plasma makes most of the elements in the sample ionize an electron to form a monovalent positive ion; MS is a "mass screening, analyzer", by selecting ions with different mass-to-nucleus ratios (m/z) to pass through to determine a certain The intensity of each ion, and then analyze and calculate the intensity of a certain element.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a rapid screening method for abnormal elements in liquor, through the screening of the method, the pollution risk of elements in liquor is completely avoided, and it is especially suitable for abnormal liquor (turbidity, precipitation, obvious color, peculiar smell, etc. ) to find out the reasons to control the quality of the liquor from the factory.

The invention provides a rapid screening method for abnormal elements in liquor, comprising the following steps: using ICP-MS to perform full scanning detection on a standard wine sample and an abnormal wine sample respectively, and comparing the two ICP-MS spectra to determine Abnormal elements in abnormal wine samples;

The detection conditions of the ICP-MS are one of the following two modes:

CCT collision cell mode: scan mode: full scan; forward power: 1300～1350W; sampling depth: 100～195step; cooling airflow: 12.5～15.5L/min; auxiliary airflow: 0.67～1.15L/min; atomization Air flow: 0.80～1.00L/min; CCT collision gas composition: 7%H ₂ , 93%He; CCT collision air flow: 5.3～6ml/min; Peristaltic pump speed: 30r/min;

Standard mode: scanning mode: full scan; forward power: 1250-1350W; sampling depth: 100-210step; cooling air flow: 12.5-15.5L/min; auxiliary air flow: 0.67-1.15L/min; atomizing air flow : 0.80～1.00L/min; speed of peristaltic pump: 30r/min.

Among them, the above-mentioned rapid screening method for abnormal elements in liquor requires pretreatment of liquor samples before detection, and the pretreatment methods are water bath evaporation or microwave digestion.

Among them, in the above-mentioned rapid screening method for abnormal elements in liquor, the water bath evaporation is to take 5-10 mL of liquor in a beaker, volatilize ethanol in a water bath at 62-67 °C, and steam until only 0.4-0.6 mL of liquid remains in the beaker, Dilute with 3 to 6 mL of 1% nitric acid solution, shake well, transfer to a 50 mL volumetric flask, wash the plastic beaker 3 to 5 times with 1% nitric acid solution, transfer the washing solution to the volumetric flask, and finally dilute to 1% nitric acid solution to 50mL.

Among them, in the above-mentioned rapid screening method for abnormal elements in liquor, the microwave digestion is to take 5-10 mL of liquor, volatilize ethanol to 2-4 mL under the condition of less than 65°C on an acid scavenger, add 5-6 mL of nitric acid and leave it for 1 hour. , digested with a microwave digestion apparatus, taken out after cooling, and then placed on an acid scavenger under the condition of less than 65 ℃ for 50 min, and the volume was adjusted to 25 mL with water, and then mixed.

Among them, in the above-mentioned rapid screening method for abnormal elements in liquor, the digestion procedure of the microwave digestion instrument is as follows: the temperature is raised to 120°C at a rate of 10-15°C/min, and kept for 8-10min; and then the temperature is 3-5°C/min The temperature was raised to 150 °C at a rate of 15 to 20 min; finally, the temperature was raised to 180 °C at a rate of 3 to 5 °C/min and held for 30 min.

Wherein, in the above-mentioned rapid screening method for abnormal elements in white wine, the standard wine sample is the qualified finished wine of the abnormal wine sample brand over the years.

Compared with the prior art, the beneficial effects of the present invention are:

The method of the invention is aimed at when the elements in the unknown sample are abnormal (for example, turbidity, precipitation and discoloration appear in the liquor), by scanning the abnormal sample and the elements in the processing liquid of the qualified wine sample of the same brand over the years, the ICP-MS full scan of the two samples is compared. The spectrum can be screened out quickly and without omission, which plays an important guiding role in the search for abnormal causes.

Description of drawings

Figure 1 M/Z20-60 mass spectrum of 3 qualified liquor samples of a certain brand of liquor over the years;

Figure 2 M/Z50-210 mass spectrum of 3 qualified liquor samples of a certain brand of liquor over the years;

Figure 3 M/Z20-60 mass spectrum of wine samples with abnormal taste and qualified wine samples of the same brand over the years;

Figure 4 M/Z50-210 mass spectrum of wine samples with abnormal taste and qualified wine samples of the same brand over the years;

Figure 5 M/Z20-60 mass spectrum of slightly cloudy wine sample 1 and the same brand of qualified wine samples over the years;

Figure 6 M/Z60-210 mass spectrum of slightly cloudy wine sample 1 and the same brand of qualified wine samples over the years;

Figure 7 M/Z0-210 mass spectrum of slightly cloudy wine sample 2 and the same brand of qualified wine samples over the years.

Detailed ways

The invention provides a rapid screening method for abnormal elements in liquor, comprising the following steps: using ICP-MS to perform full scanning detection on a standard wine sample and an abnormal wine sample respectively, and comparing the two ICP-MS spectra to determine Abnormal elements in abnormal wine samples;

The detection conditions of the ICP-MS are one of the following two modes:

CCT collision cell mode: scan mode: full scan; forward power: 1300～1350W; sampling depth: 100～195step; cooling airflow: 12.5～15.5L/min; auxiliary airflow: 0.67～1.15L/min; atomization Air flow: 0.80～1.00L/min; CCT collision gas composition: 7%H2, 93%He; CCT collision gas flow: 5.3～6ml/min; Peristaltic pump speed: 30r/min;

Standard mode: scanning mode: full scan; forward power: 1250-1350W; sampling depth: 100-210step; cooling air flow: 12.5-15.5L/min; auxiliary air flow: 0.67-1.15L/min; atomizing air flow : 0.80～1.00L/min; speed of peristaltic pump: 30r/min.

The CCT collision cell mode is suitable for routine scanning and screening of elements, but in the case of low element concentrations, the standard mode should be used for scanning and screening.

The method of the invention can quickly screen out abnormal elements in abnormal wine samples, the types include: metal Li, Be, Na, Mg, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Cs, Ba, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Tl, Pb, Bi, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, U, Np, Pu; non-metallic B, Si, P, S, Cl, As, Se, Br, Te, I, with short detection time and wide range, covering almost all elements in nature (except elements with short half-life), Compared with the national standard "Determination of Multiple Elements in Food", only 26 elements can be determined by peak-hopping scanning, and the number of indicators analyzed by this method is much larger than that in the national (enterprise) standard.

Since the samples used in the examples of the present invention are all real finished wines, some elements in the wine (such as M/Z 78Se, 89Y, 121Sb, 139La, etc.) are not easy to fall within the range of the present invention due to their low ionic strength It is observed that in actual operation, it can be observed on the instrument software diagram by adjusting the range of the ordinate axis at any time. A picture in this article is divided into M/Z50-210 and M/Z20-60, just to facilitate the observation of various elements that are not in the same range.

The wine sample of the present invention needs to be pretreated before detection, and the pretreatment method is water bath evaporation or microwave digestion.

The water bath evaporation is to take 5-10 mL of white wine in a beaker, volatilize ethanol in a water bath at 62-67 ℃, steam until only 0.4-0.6 mL of liquid remains in the beaker, dilute with 3-6 mL of 1% nitric acid solution and shake up carefully. Transfer to a 50mL volumetric flask, then wash the plastic beaker with 1% nitric acid solution for 3 to 5 times, transfer the washing solution to the volumetric flask, and finally dilute to 50mL with 1% nitric acid solution;

The microwave digestion is to take 5-10 mL of white wine, volatilize ethanol to 2-4 mL under the condition of less than 65 ℃ on the acid scavenger, add 5-6 mL of nitric acid and place for 1 hour, digest with a microwave digestion device, take out after cooling, and then re-heat. Put it on an acid scavenger under the condition of less than 65℃ and heat it for 50min, dilute to 25mL with water, and mix well.

The digestion procedure of the microwave digestion apparatus is as follows: raise the temperature to 120°C at a rate of 10-15°C/min and hold for 8-10 minutes; then raise the temperature to 150°C at a rate of 3-5°C/min and hold for 15-20min; finally The temperature was raised to 180°C at a rate of 3 to 5°C/min and held for 30 min.

The specific embodiments of the present invention will be further described below with reference to the examples, but the present invention is not limited to the scope of the described examples.

Main instruments used in the examples: X-series2 inductively coupled plasma mass spectrometer, Thermo Company, USA; MARS 6 microwave digestion instrument, CEM Company; water bath.

Embodiment 1, the detection of multiple elements in the qualified wine samples of a certain brand liquor over the years

Standard wine samples: 3 qualified wine samples of a certain brand of liquor over the years (different batches of finished wine), all of which are 52% vol.

Pre-treatment (microwave digestion method): Take 10 mL of liquor sample, volatilize it to 4 mL in an acid scavenger at 65°C, add 6 mL of nitric acid, put it on for 1 h, tighten the lid, and digest according to the standard operating procedure of the microwave digestion apparatus. After cooling, slowly open the tank cover to exhaust air, rinse the inner cover with a small amount of water, place the digestion tank on the acid scavenger, heat at 65°C for 50min, dilute to 25mL with water, and mix well to obtain a liquor treatment solution. At this time, the content of organic matter in wine samples should be less than 4%. The digestion procedure of the microwave digestion apparatus is: raise the temperature to 120°C at a rate of 15°C/min and hold for 8 minutes; then raise the temperature to 150°C at a rate of 5°C/min and hold for 15 minutes; and finally raise the temperature to 180°C at a rate of 5°C/min. ℃ for 30min.

Detection conditions of ICP-MS (CCT collision cell mode): scanning mode: full scan; forward power: 1320W; sampling depth: 187step; cooling gas flow: 13.0L/min; auxiliary gas flow: 0.80L/min; atomization Air flow: 0.88 L/min; CCT collision gas composition: 7% H ₂ , 93% He; CCT collision gas flow: 5.95 ml/min; peristaltic pump rotation speed: 30 r/min.

ICP-MS was used to test various elements in the above samples under the state of full scan. The results are shown in Figure 1 and Figure 2.

Figures 1 and 2 show that the peak heights of each element in the ICP-MS full scans of the three qualified wine samples over the years are basically the same, indicating that after the normal production process, the types and contents of various elements in this brand of liquor are stable throughout the year.

Embodiment 2. Detection of multiple elements in wine samples with abnormal taste

Abnormal wine sample: 52% vol wine sample with abnormal taste.

Standard wine samples: 2 wine samples with abnormal taste and the same brand liquor over the years (different batches of finished wine), all of which are 52% vol.

Pretreatment: The above wine samples were pretreated according to the microwave digestion method in Example 1.

Detection conditions of ICP-MS (CCT collision cell mode): scanning mode: full scan; forward power: 1320W; sampling depth: 187step; cooling gas flow: 13.0L/min; auxiliary gas flow: 0.80L/min; atomization Air flow: 0.88 L/min; CCT collision gas composition: 7% H ₂ , 93% He; CCT collision gas flow: 5.95 ml/min; peristaltic pump rotation speed: 30 r/min.

ICP-MS was used to test various elements in the above abnormal wine samples under the full scan state. The results are shown in Figure 3 and Figure 4.

Observing the spectrum of wine samples with abnormal taste (Figure 3 and Figure 4), the normal amount of elements is the result of qualified wine samples of the same brand over the years, and the abnormal amount of elements is the result of wine samples with abnormal taste. It is found that Mg, K, Ca, Fe, The peaks of Mn, Cu, Zn, Sr and other indicators were significantly higher than those of the standard wine samples, indicating that the abnormal content of some metal elements in the abnormal wine samples caused the inconsistency in the taste of the liquor, and the winery needed to check the production process on this basis. The above results show that it is feasible to use the method of the present invention to screen abnormal elements in liquor (compared with qualified liquor samples over the years).

Embodiment 3. Detection of multiple elements in slightly cloudy wine sample 1

Abnormal wine sample: slightly cloudy wine sample 1, 52% vol.

Standard wine samples: Slightly cloudy wine sample 1, 2 qualified wine samples of the same brand liquor over the years (different batches of finished wine), all of which are 52% vol.

Pre-treatment (evaporation in water bath): Take 10ml of liquor sample in plastic biscuits, volatilize ethanol in a water bath at 65°C, steam until only about 0.5ml of liquid remains in the plastic beaker, dilute with 5ml of nitric acid solution (1%) and shake well Then carefully transfer it to a 50ml volumetric flask, wash the plastic beaker 4 times with nitric acid solution, transfer the washing solution to the volumetric flask, and finally make up to 50ml with nitric acid solution.

Detection conditions of ICP-MS (CCT collision cell mode): scanning mode: full scan; forward power: 1320W; sampling depth: 187step; cooling gas flow: 13.0L/min; auxiliary gas flow: 0.80L/min; atomization Air flow: 0.88 L/min; CCT collision gas composition: 7% H ₂ , 93% He; CCT collision gas flow: 5.95 ml/min; peristaltic pump rotation speed: 30 r/min. .

ICP-MS was used to test various elements in the above wine samples under the full scan state. The results are shown in Figure 5 and Figure 6.

Observing the spectrum of slightly cloudy wine sample 1 (Figure 5, Figure 6), the normal amount of elements is the result of qualified wine samples of the same brand over the years, and the abnormal amount of elements is the result of slightly cloudy wine sample 1. It is found that Fe, Sn, Ba in the slightly cloudy wine sample 1 The peaks of other indicators are significantly higher than those of the standard wine sample, indicating that the content of some metal elements in abnormal wine sample 1 is abnormal (especially the abnormal Ba content), which causes the liquor to appear slightly turbid. The above results once again show that it is feasible to use the method of the present invention to screen for abnormal elements in liquor (compared with qualified liquor samples over the years).

Embodiment 4. Detection of multiple elements in slightly cloudy wine sample 2

Abnormal wine sample: slightly cloudy wine sample 2, 52% vol.

Standard wine samples: 2 slightly cloudy wine samples 2 qualified wine samples of the same brand of liquor over the years (different batches of finished wine), all of which are 52% vol.

Pretreatment (water bath evaporation): the above wine samples were pretreated according to the water bath evaporation method in Example 3

ICP-MS detection conditions (standard mode): scanning mode: full scan; forward power: 1320W; sampling depth: 187step; cooling gas flow: 13.0L/min; auxiliary gas flow: 0.80L/min; atomizing gas flow : 0.88L/min; peristaltic pump speed: 30r/min.

ICP-MS was used to test various elements in the above wine samples under full scan state, and the results are shown in Figure 7.

Observing the spectrum of the slightly cloudy wine sample 2 (Figure 7), the normal amount of elements is the result of the qualified wine samples of the same brand over the years, and the abnormal amount of elements is the result of the slightly cloudy wine sample 2, which is similar to the result of Example 3, and also exists in the slightly cloudy wine sample 2. The phenomenon that the peaks of Sn, Ba and other indicators are significantly higher than that of the standard wine sample, indicating that the abnormality of the wine sample may also be caused by the abnormal content of Sn, Ba and other elements (especially the abnormal content of Ba). The above results once again show that it is feasible to use the method of the present invention to screen for abnormal elements in liquor (compared with qualified liquor samples over the years).

Claims (6)

1. The method for rapidly screening abnormal elements in white spirit is characterized by comprising the following steps: respectively carrying out full-scan detection on the standard wine sample and the abnormal wine sample by adopting ICP-MS, and comparing two ICP-MS spectrograms to judge abnormal elements in the abnormal wine sample;

the detection condition of the ICP-MS is one of the following two modes:

CCT collision cell mode: scanning mode: full scanning; forward power: 1300-1350W; sampling depth: 100 to 195 step; cooling air flow: 12.5-15.5L/min; auxiliary air flow rate: 0.67-1.15L/min; flow rate of atomizing gas: 0.80-1.00L/min; CCT collision gas composition: 7% H₂93% He; CCT collision air flow rate: 5.3-6 ml/min;rotation speed of peristaltic pump: 30 r/min;

standard mode: the scanning mode is as follows: full scanning; forward power: 1250-1350W; sampling depth: 100 to 210 step; cooling air flow: 12.5-15.5L/min; auxiliary air flow rate: 0.67-1.15L/min; flow rate of atomizing gas: 0.80-1.00L/min; rotation speed of peristaltic pump: 30 r/min.

2. The method for rapidly screening abnormal elements in white spirit according to claim 1, which is characterized in that: the wine sample needs to be pretreated before detection, and the pretreatment mode is water bath evaporation or microwave digestion.

3. The method for rapidly screening abnormal elements in white spirit according to claim 2, which is characterized in that: and in the water bath evaporation, 5-10 mL of white spirit is taken into a beaker, ethanol is volatilized at 62-67 ℃ in a water bath kettle, the white spirit is evaporated until only 0.4-0.6 mL of liquid is left in the beaker, the white spirit is diluted by 3-6 mL of 1% nitric acid solution and shaken uniformly and then transferred into a 50mL volumetric flask, the plastic beaker is washed by 3-5 times by using the 1% nitric acid solution, the washing liquid is transferred into the volumetric flask, and finally the volume is fixed to 50mL by using the 1% nitric acid solution.

4. The method for rapidly screening abnormal elements in white spirit according to claim 2, which is characterized in that: the microwave digestion is to take 5-10 mL of white spirit, volatilize ethanol to 2-4 mL under the condition of less than 65 ℃ on an acid expeller, add 5-6 mL of nitric acid, stand for 1h, digest by using a microwave digestion instrument, cool and take out, then place on the acid expeller to heat for 50min under the condition of less than 65 ℃, fix the volume to 25mL by using water, and mix uniformly to obtain the product.

5. The method for rapidly screening abnormal elements in white spirit according to claim 4, which is characterized in that: the digestion program of the microwave digestion instrument is as follows: heating to 120 ℃ at the speed of 10-15 ℃/min, and keeping for 8-10 min; heating to 150 ℃ at the speed of 3-5 ℃/min, and keeping for 15-20 min; and finally, heating to 180 ℃ at the speed of 3-5 ℃/min, and keeping for 30 min.

6. The method for rapidly screening abnormal elements in white spirit according to any one of claims 1 to 5, which is characterized by comprising the following steps: the standard wine sample is qualified finished wine of abnormal wine sample brands all the year round.

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