Method for constructing infrared spectrum library of visible foreign matters in white spirit

Abstract

The invention mainly relates to the technical field of spectrum. The invention provides a white spirit visible foreign matter infrared spectrum library construction method, and aims to quickly identify sources of visible foreign matters in white spirit, the method comprises the following steps: step S1, carrying out risk assessment on production nodes which may introduce visible foreign matters in a wine brewing process, and determining risk sources of the production nodes based on a risk assessment result; s2, preparing a visible foreign matter sample based on the determined risk source, and collecting an infrared spectrum image of the visible foreign matter sample; s3, establishing an infrared spectrum library of the visible foreign matters in the white spirit according to the collected infrared spectrum images of the visible foreign matter samples, enabling the infrared spectrum image of each visible foreign matter to correspond to the name, the source and the preparation mode of the visible foreign matters, and establishing the infrared spectrum library of the visible foreign matters in the white spirit, and rapidly identifying the type and source of the visible foreign matters in the white spirit based on the established infrared spectrum library.

Description

Technical Field

[0001] The invention mainly relates to the field of spectral technology, and in particular to a method for constructing an infrared spectral library of visible foreign matter in liquor. Background Art

[0002] In recent years, with the development of spectral technology, the application of infrared spectroscopy has become increasingly mature, which is closely related to its advantages such as convenient operation, high sensitivity, and non-destructive testing. When using infrared spectroscopy for analysis, the measured spectrum is usually compared with the spectrum of a known sample or a standard spectrum. Although commercial spectral libraries are constantly being updated and improved, the quality of their spectra is uneven. When analyzing unknown substances, the search results are not satisfactory, and commercial spectral libraries have the following shortcomings: low resolution, many spectra only have codes, no molecular formula, structural formula, and CAS number; the classification of spectra is relatively chaotic (the infrared spectral library also includes Raman spectra); standard spectra are relatively expensive, and the spectral range of spectrum acquisition is not uniform, etc.

[0003] Liquor produced by the solid-state method is brewed, stored, blended, pulped, and packaged. Lax quality control in each link of liquor production will lead to the risk of visible foreign matter in the finished liquor. Liquor is a relatively complex matrix. Visible foreign matter may change its chemical properties after long-term immersion in liquor, resulting in possible displacement of the collected spectral data, which brings challenges to the identification of insoluble substances. It is difficult to accurately characterize them directly through infrared spectroscopy. Summary of the invention

[0004] Technical Problems to be Solved by the Invention

[0005] The invention provides a method for constructing an infrared spectrum library of visible foreign matter in liquor, aiming at quickly identifying the sources of visible foreign matter in liquor.

[0006] The technical solution adopted by the present invention to solve the above technical problems

[0007] The method for constructing infrared spectral library of visible foreign matter in liquor includes:

[0008] Step S1: Conduct risk assessment on production nodes that may introduce visible foreign matter during the winemaking process, and determine the risk source of each production node based on the risk assessment results;

[0009] Step S2: preparing a visible foreign matter sample based on the determined risk source, and collecting an infrared spectrum image of the visible foreign matter sample;

[0010] Step S3: establishing an infrared spectrum library of visible foreign matter in liquor according to the collected infrared spectrum images of the visible foreign matter samples, and matching the infrared spectrum image of each visible foreign matter with the name, source, and preparation method of the visible foreign matter.

[0011] Furthermore, the preparation of the visible foreign matter sample based on the determined risk source in step S2 specifically includes:

[0012] If the visible foreign matter sample is a solid sample, the solid sample is pressed thin by an infrared pressing mold and selected onto the window of the infrared spectrometer; the solid sample is specifically a solid foreign matter generated at each production node in the winemaking process that has not entered the liquor sample;

[0013] If the visible foreign matter sample is a visible foreign matter in a wine sample, the visible foreign matter in the wine sample is filtered with a filter membrane, and the visible foreign matter with a volume larger than a set value is picked out to prepare a visible foreign matter sample in accordance with the sample preparation method of a solid sample, and the visible foreign matter sample with a volume smaller than the set value is directly picked out and placed on the window of the infrared spectrometer;

[0014] The infrared window is a BAF2 window with a size of 13 mm×2 mm; the filter membrane is a silicon membrane with a pore size of 1 μm and a size of 1 cm×1 cm.

[0015] Furthermore, the step S2 of collecting the infrared spectrum image of the visible foreign matter sample specifically includes:

[0016] Step S21: placing the prepared visible foreign matter target sample window on an adapted slide, and transferring it to a stage, moving and positioning the sample on the stage in the observation area of ​​the objective lens of the infrared spectrometer; adjusting the stage aperture illumination parameters to make the sample clearly visible in the view;

[0017] Step S22: using the point scanning function of the infrared spectrum device to mark the sample particles on the view, and after marking, collecting the infrared spectrum of the sample particles, selecting a background position on the window that is not covered by the sample for background testing according to the prompt of the infrared spectrum device, and collecting the infrared spectrum according to the marking order of the sample particles;

[0018] Step S23: Preprocessing the infrared spectra of the collected sample particles and performing statistical analysis to obtain the average infrared spectrum of multiple infrared spectra, and using the average infrared spectrum as the standard spectrum image of the corresponding visible foreign matter sample; wherein the preprocessing includes baseline correction and smoothing.

[0019] Furthermore, the stage in step S21 is a Nicolet iN10 automatic stage, and adjusting the stage aperture lighting parameters includes: adjusting the stage lighting parameters to upper lighting: 0, aperture lighting: 0, lower lighting: 50; the width and height of the aperture are both 150um, and the angle is 0°.

[0020] Furthermore, the acquisition parameters of the infrared spectroscopy device in step S22 are acquisition mode: transmission mode, detector: MCT detector, and the spectral range of the detector is 4000cm -1 -675cm -1 The single beam spectrum of each sample particle is scanned at least 16 times, the single scan time is at least 3 seconds, and the total spectrum collected for each particle is not less than 100.

[0021] Furthermore, the calculation of the average infrared spectrum in step S23 uses the statistical spectrum function in ommic.

[0022] Furthermore, the visible foreign matter in the wine sample in step 2 includes different biological tissues of raw and auxiliary materials for brewing in different developmental states, lees and koji medicines of different fermentation times, and the solid samples include processing aids used in the post-processing stage of liquor, gaskets for wine delivery pipelines, scale, wine packaging materials and bottle caps.

[0023] Beneficial Effects of the Invention

[0024] The method for constructing an infrared spectrum library of visible foreign matter in liquor of the present invention performs risk assessment on production nodes that may introduce visible foreign matter in the brewing process, and determines the risk source of each production node based on the risk assessment result; prepares visible foreign matter samples based on the determined risk source, and collects infrared spectrum images of the visible foreign matter samples; corresponds the infrared spectrum image of each visible foreign matter with the name, source, and preparation method of the visible foreign matter, and establishes an infrared spectrum library of visible foreign matter in liquor. Compared with traditional commercial spectrum libraries, the risk sources corresponding to the spectra of visible foreign matter in the spectrum library established in the present invention are determined according to the actual brewing process of liquor, and the reliability and accuracy of identifying foreign matter in liquor based on the established infrared spectrum library of visible foreign matter are higher; at the same time, it can also make up for the deficiency that the existing infrared spectrum diagram is only applicable to single components and has no ability to identify mixtures, and provides an important reference for the subsequent qualitative identification and traceability of insoluble substances found in liquor. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a flow chart of the method for constructing an infrared spectral library of visible foreign matter in liquor according to the present invention;

[0026] Figure 2 It is a schematic diagram of the data structure of the visible foreign matter spectrum library of liquor in the present invention. DETAILED DESCRIPTION

[0027] like Figure 1 As shown, the method for constructing an infrared spectral library of visible foreign matter in liquor of the present invention specifically comprises:

[0028] Conduct risk assessments on production nodes that may introduce visible foreign matter during the winemaking process, and determine the risk sources of each production node based on the risk assessment results; the risk sources involved include but are not limited to raw and auxiliary materials for winemaking, such as sorghum, corn, rice, wheat, glutinous rice, bran, and other biological tissues in different raw and cooked states, distiller's grains and koji with different fermentation times in the dough making, culture and maturation stages, processing aids used in the post-processing stage of liquor, gaskets for wine delivery pipelines, scale, wine packaging materials, bottle caps, etc.

[0029] Prepare visible foreign matter samples for each of the above risk sources.

[0030] If it is a solid sample, the visible foreign matter sample is pressed thin with an infrared pressing mold, and the pressed standard sample is picked out and placed on the microscopic infrared window. The solid sample is specifically the solid foreign matter produced at each production node in the winemaking process that has not entered the liquor sample. If it is a visible foreign matter in the liquor sample, after filtering with a filter membrane, the larger visible foreign matter samples are picked out and prepared according to the sample preparation method of solid samples, and the smaller ones are directly tested on the machine; wherein the window is a BAF2 window with a size of 13mm×2mm; preferably, the filter membrane is a silicon membrane with a pore size of 1μm and a size of 1cm×1cm.

[0031] Collect infrared spectral images of the visible foreign matter samples prepared based on different risk sources.

[0032] (1) Place the window on a suitable slide and transfer it to the stage. Use the joystick configured on the Nicolet iN10 Fourier transform infrared microscope to move the visible foreign matter sample on the stage to the observation area of ​​the objective lens; adjust the aperture illumination, focus and stitch the entire image. Adjust the illumination parameters to upper illumination: 100, aperture illumination: 0, lower illumination: 50; the width and height of the aperture are both 150um, and the angle is 0°.

[0033] (2) Use the point scanning function of the infrared spectrometer to mark the target particles on the obtained mosaic image. After marking, collect infrared spectra of the visible foreign matter sample particles. According to the prompt, select a background position on the BAF2 that is not covered by the sample for background testing. The instrument will collect infrared spectra according to the order of particle marking. The infrared spectrum of each sample particle is collected in 3 seconds, scanned 16 times, and the collection mode is transmission mode. The MCT detector is used. The standard samples of the built library are collected no less than 3 times, and the total number of collected spectra is no less than 100.

[0034] (3) Perform spectral preprocessing on the collected spectra of the target particles, including but not limited to baseline correction and smoothing, and then perform statistical analysis on the spectra to obtain the average spectrum of no less than 100 spectral images, and use the average spectrum as the original spectrum of the sample. The average spectrum can avoid the randomness and errors that occur when collecting spectra at a single sampling point, thereby improving the accuracy of the data.

[0035] Add the obtained average spectrum as the original spectrum to the self-built library, number the self-built spectrum, and follow the steps below: Figure 2 The name, source, sample preparation method, etc. of the spectrum are indicated in the manner shown, and by analogy, an infrared spectrum library of visible foreign matter in liquor is established.

[0036] Example

[0037] A plurality of liquor samples containing visible foreign matter and solid samples that did not enter the liquor samples but appeared in the wine production process were collected, and after the samples were prepared according to the above-mentioned sample preparation method, infrared spectral images of each sample were collected. The accuracy of the infrared spectral library of visible foreign matter in liquor established in this embodiment for detecting proteins, erucamide, calcium sulfate, diatomaceous earth as a liquor filter aid, liquor filter gauze, starch, cooked sorghum, bottle caps (PET) and cooked wheat husks is compared with the accuracy of the commercial spectral library as shown in Table 1.

[0038] Table 1 Infrared spectra of visible foreign matter in liquor and matching results of spectral library search results

[0039]

[0040] Based on the above, the infrared spectrum library of visible foreign matters constructed by the method for constructing an infrared spectrum library of visible foreign matters in liquor described in the present invention can improve the reliability and accuracy of identifying visible foreign matters in liquor.

Claims

1. A method for constructing an infrared spectral library of visible foreign matter in liquor, characterized in that: include: Step S1: Conduct risk assessment on production nodes that may introduce visible foreign matter during the winemaking process, and determine the risk source of each production node based on the risk assessment results; Step S2: preparing a visible foreign matter sample based on the determined risk source, and collecting an infrared spectrum image of the visible foreign matter sample; Step S3: establishing an infrared spectrum library of visible foreign matter in liquor according to the collected infrared spectrum images of the visible foreign matter samples, and matching the infrared spectrum image of each visible foreign matter with the name, source, and preparation method of the visible foreign matter.

2. The method for constructing an infrared spectroscopy library of visible foreign matter in liquor according to claim 1, characterized in that: The step S2 of preparing the visible foreign matter sample based on the determined risk source specifically includes: If the visible foreign matter sample is a solid sample, the solid sample is pressed thin by an infrared pressing mold and selected onto the window of the infrared spectrometer; the solid sample is specifically a solid foreign matter generated at each production node in the winemaking process that has not entered the liquor sample; If the visible foreign matter sample is a visible foreign matter in a wine sample, the visible foreign matter in the wine sample is filtered with a filter membrane, and the visible foreign matter with a volume larger than a set value is picked out to prepare a visible foreign matter sample in accordance with the sample preparation method of a solid sample, and the visible foreign matter sample with a volume smaller than the set value is directly picked out and placed on the window of the infrared spectrometer; The infrared window is a BAF2 window with a size of 13 mm×2 mm; the filter membrane is a silicon membrane with a pore size of 1 μm and a size of 1 cm×1 cm.

3. The method for constructing an infrared spectroscopy library of visible foreign matter in liquor according to claim 1, characterized in that: The step S2 of collecting the infrared spectrum image of the visible foreign matter sample specifically includes: Step S21: placing the prepared visible foreign matter target sample window on an adapted slide, and transferring it to a stage, moving and positioning the sample on the stage in the observation area of ​​the objective lens of the infrared spectrometer; adjusting the stage aperture illumination parameters to make the sample clearly visible in the view; Step S22: using the point scanning function of the infrared spectrum device to mark the sample particles on the view, and after marking, collecting the infrared spectrum of the sample particles, selecting a background position on the window that is not covered by the sample for background testing according to the prompt of the infrared spectrum device, and collecting the infrared spectrum according to the marking order of the sample particles; Step S23: Preprocessing the infrared spectra of the collected sample particles and performing statistical analysis to obtain the average infrared spectrum of multiple infrared spectra, and using the average infrared spectrum as the standard spectrum image of the corresponding visible foreign matter sample; wherein the preprocessing includes baseline correction and smoothing.

4. The method for constructing an infrared spectroscopy library of visible foreign matter in liquor according to claim 3, characterized in that: The stage in step S21 is a Nicolet iN10 automatic stage, and adjusting the stage aperture lighting parameters includes: adjusting the stage lighting parameters to upper lighting: 0, aperture lighting: 0, lower lighting: 50; the width and height of the aperture are both 150um, and the angle is 0°.

5. The method for constructing an infrared spectroscopy library of visible foreign matter in liquor according to claim 4, characterized in that: The acquisition parameters of the infrared spectroscopy device in step S22 are acquisition mode: transmission mode, detector: MCT detector, and the spectral range of the detector is 4000cm -1 -675cm -1 The single beam spectrum of each sample particle is scanned at least 16 times, the single scan time is at least 3 seconds, and the total spectrum collected for each particle is not less than 100.

6. The method for constructing an infrared spectroscopy library of visible foreign matter in liquor according to claim 1, characterized in that: The calculation of the average infrared spectrum in step S23 uses the statistical spectrum function in ommic.

7. The method for constructing an infrared spectroscopy library of visible foreign matter in liquor according to claim 1, characterized in that: The visible foreign matter in the wine sample described in step 2 includes different biological tissues of raw and auxiliary materials for brewing in different developmental states, lees and koji medicines of different fermentation times; the solid samples include processing aids used in the post-processing stage of liquor, gaskets for wine delivery pipelines, scale, wine packaging materials and bottle caps.

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