In-situ headspace sampling device applied to fermented grain detection

Abstract

The invention discloses an in-situ headspace sampling device applied to fermented grain detection, and belongs to the technical field of gas sampling. The device comprises a sampling tube, a handle, a connecting rod, a headspace sampling head and a sampling head cover. The sampling device is directly inserted into the fermented grains, the sampling head cover can support a sample gas chamber, a fermented grain gas sample around the sampling head cover continuously permeates into the sample gas chamber, the sample gas is fed into an analytical instrument by adopting a headspace principle, and the in-situ deep sampling of the fermented grains is realized.

Description

Technical Field

[0001] The invention belongs to the technical field of gas sampling and relates to an in-situ headspace sampling device applied in the field of fermented grains detection. Background Art

[0002] Due to its unique fermentation process and unique flavor characteristics, Baijiu has had a wide impact worldwide. During the production process, the microbial flora in the environment and the environment undergo dynamic development and balance during the fermentation of the mash, regulating the changes in the types of microorganisms in the cellar and the generation and accumulation of metabolites, thus affecting the quality and style of Luzhou-flavor Baijiu. Taking mash as the object, studying the dynamic changes in the chemical composition of mash over time during the fermentation process can understand the source and derivative relationship of the complex and diverse components in Baijiu, provide a scientific basis for analyzing the characteristics of microorganisms in the cellar, and coordinate the role of functional bacteria in the mash in the cellar to improve the level of Baijiu production technology.

[0003] In the analysis and research of fermented grains, it is usually necessary to determine the chemical composition in the fermented grains. Due to the complex composition of fermented grains, the large number of interferences and the complex environment, the in-situ online detection technology and methods of fermented grains have become a major problem. The conventional method for fermented grains determination is to first take a certain amount of fermented grain samples in the wine cellar, then send them to the laboratory for a series of relatively complex sample pretreatments, and then use the headspace method or solution extraction method and other sampling methods, and then use chromatography, mass spectrometry, spectroscopy and their combined equipment for detection.

[0004] Whether it is a pile of mash or sealed in a cellar, the physical form of the mash changes continuously during the fermentation process, from the original granular form to a sludge form. The mash is fermented in layers, and the chemical composition of mash at different depths is different, which poses a great challenge to mash sampling.

[0005] There are many patents for wine mash solid samplers, such as conical sampling heads (CN215985309U), sampling shovels (CN219798748U), hollow tubes with sampling scrapers (CN212059457U), and wine mash gas detection, including gas detection in wine mash tanks (CN116256417A) and detection through the air inlet end of the air guide structure inserted into the test environment (CN115901661A). Summary of the invention

[0006] The main purpose of the present invention is to overcome the deficiencies of the prior art and provide an in-situ headspace sampling device for fermented grains detection. The present invention solves the problem of in-situ sampling and deep sampling of fermented grains, and realizes in-situ sampling and online analysis of fermented grains. The device is directly inserted into the fermented grains, and the sampling head cover can support a sample air chamber. The fermented grains gas sample around the sampling head cover continuously penetrates into the sample air chamber. The headspace principle is adopted to send the sample gas into the analytical instrument to realize in-situ deep sampling of the fermented grains, which is then analyzed by the analytical instrument. By selecting connecting rods of different lengths, fermented grains sampling at different depths can be realized, providing a powerful sampling tool support for studying the chemical substances of layered fermentation of fermented grains.

[0007] The technical solution of the present invention is specifically as follows:

[0008] The present invention provides an in-situ headspace sampling device for detecting fermented grains, comprising a sampling tube, a handle, a connecting rod, a headspace sampling head and a sampling head cover;

[0009] One end of the sampling tube is connected to the analytical instrument or the sampling bottle, and the other end passes through the handle and the connecting rod in sequence and is connected to the head space sampling head; the head space sampling head is connected to the head cover;

[0010] The headspace sampling head is a hollow cylindrical structure with a protrusion in the middle. The headspace sampling head becomes thicker at one end toward the sampling head cover to form a sampling head air chamber, and the other end is inserted into a sampling tube. A filter element is connected to the end of the sampling head air chamber toward the sampling head cover to further prevent the mash particles from blocking the sampling channel. The sampling head air channels are evenly distributed around the headspace sampling head to facilitate the inflow of external gas.

[0011] The sampling head cover is a cylindrical structure with a hollow center and a triangular arrow-shaped front end. A plurality of long hollow recessed areas are evenly distributed on the cylindrical structure of the sampling head cover, and a filter screen is covered on the outside of the area. The rear end of the sampling head cover is connected to the head space sampling head. The head space sampling head has a filter element at one end inserted into the center of the sampling head cover, and a sample air chamber is formed between the front end of the filter element and the inside of the sampling head cover. The mash sample gas continuously penetrates the sample into the sample air chamber through the filter screen.

[0012] The connecting rod is a hollow cylinder with a thick end, a thin end connected to a hollow cylindrical handle, and a thick end connected to a headspace sampling head, and a connecting rod air chamber is formed between the sampling heads.

[0013] The gap between the sampling tube, the handle and the connecting rod forms a connecting rod airway;

[0014] The connecting rod air channel, the connecting rod air chamber, the sampling head air channel, the sample air chamber, the sampling head air chamber, and the interior of the sampling tube are sequentially connected.

[0015] Furthermore, in the above technical solution, the length of the connecting rod can be adjusted according to sampling needs, and a plurality of connecting rods are provided in series to extend the sampling distance.

[0016] Furthermore, in the above technical solution, the length of the connecting rod is 0.2-3m.

[0017] Furthermore, in the above technical solution, a heating device is provided on the outer wall of the sampling tube. The outer wall of the sampling tube can be heated to reduce sample residue.

[0018] Furthermore, in the above technical solution, the number of meshes of the filter is 100-1000, and the number of meshes of the filter is determined by the properties of the fermented grains, and is changed once for each sample. When the fermented grains are granular, the number of meshes is 100-500; when the fermented grains are sludge-like, the number of meshes is 500-1000,

[0019] Furthermore, in the above technical solution, a filter fixing rib is respectively placed on both ends of the filter to firmly fix the filter on the sampling head cover for easy replacement.

[0020] After the headspace sampling device is inserted into the mash, when sampling, the sampling pump of the analyzer in the sampling tube draws air, and the ambient gas enters the sample air chamber along the connecting rod airway, the connecting rod air chamber, the sampling head airway, and the gas components of the mash sample continuously evaporate into the sample air chamber. Driven by the airflow, the sample gas passes through the filter element, along the sampling head air chamber and the sampling tube, and then enters the analyzer to achieve in-situ deep sampling.

[0021] Advantageous Effects of the Invention

[0022] The present invention proposes an in-situ headspace sampling device for detecting mash. The device is designed based on the headspace principle and can collect the chemical components volatilized from the mash online in situ. Sampling at different depths can be achieved by adjusting the length of the connecting rod. The unique airway design solves the problem of inserting headspace gas at a depth of more than 1-2m. The arrow design facilitates the insertion of the sampling device into the mash. The two-pass filter screen effectively prevents the mash from blocking the airway, and the filter screen can be replaced conveniently after sampling. The sampling tube can be heated to reduce sample residue. The use of the patented headspace gas collection method can achieve in-situ deep sampling of the mash, reduce sample waste, and eliminate the need for pre-treatment of gas analysis, thereby achieving rapid detection and analysis of the mash. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The schematic diagram of the structure of an in-situ headspace sampling device applied to fermented grains is shown in FIG.

[0024] Figure 2 The ion mobility spectrometry sampling head in Example 2 is inserted into the fermented grains at different depths to detect the spectra;

[0025] Figure 3This is a comparison of the spectra of the same sample of mash detected by ion mobility spectrometry on the surface and inserted into the mash at a depth of 20 cm in Example 3.

[0026] In the figure, 1-sampling tube; 2-handle; 3-connecting rod airway; 4-connecting rod; 5-connecting rod air chamber; 6-head space sampling head; 7-sampling head airway; 8-sampling head air chamber; 9-filter fixing rib; 10-filter; 11-filter element; 12-sample air chamber; 13-sampling head cover. DETAILED DESCRIPTION

[0027] The following is a detailed description of the embodiments of the present invention. It should be emphasized that the following description is only exemplary and is not intended to limit the scope and application of the present invention.

[0028] Example 1

[0029] like Figure 1 As shown, an in-situ head space sampling device for fermented grains detection includes a sampling tube 1, a handle 2, a connecting rod 4, a head space sampling head 6 and a sampling head cover 13.

[0030] One end of the sampling tube is connected to the analytical instrument, and the other end passes through the handle and the connecting rod in sequence and is connected to the head space sampling head; the head space sampling head is connected to the head cover;

[0031] The head space sampling head 6 is a hollow cylindrical structure with a protrusion in the middle. The head space sampling head becomes thicker towards one end of the sampling head cover to form a sampling head air chamber 8, and the other end can be inserted into the sampling tube 1. The sampling head air chamber 8 is connected to the end of the sampling head cover to further prevent the mash particles from blocking the sampling channel. The sampling head air channel 7 is evenly distributed around the head space sampling head to facilitate the inflow of external gas.

[0032] The sampling head cover 13 is a cylindrical structure with a hollow center and a triangular arrow-shaped front end. Multiple long hollow concave areas are evenly distributed on the cylindrical structure of the sampling head cover. The outside of the area is covered with a filter screen 10. A filter screen fixing rib 9 is respectively set at both ends of the filter screen 10 to firmly fix the filter screen 10 on the sampling head cover 13 for easy replacement. The rear end of the sampling head cover is connected to the headspace sampling head 6. The headspace sampling head 6 has a filter core 11 at one end inserted into the center of the sampling head cover 13. A sample air chamber 12 is formed at the front end of the filter core 11 and the inside of the sampling head cover. The fermented grains sample gas continuously penetrates the sample into the sample air chamber 12 through the filter screen 10.

[0033] The connecting rod 4 is a hollow cylinder with a thick end, a thin end connected to a hollow cylindrical handle, and a thick end connected to a head space sampling head 6, and a connecting rod air chamber 5 is formed between the sampling heads.

[0034] The sampling tube 1 is connected to the analysis instrument at one end, passes through the handle 2 and the connecting rod 4 in sequence, and is connected to the head space sampling head 6. The gap between the sampling tube 1 and the handle 2 and the connecting rod 4 forms a connecting rod airway 3.

[0035] The connecting rod air channel, the connecting rod air chamber, the sampling head air channel, the sample air chamber, the sampling head air chamber, and the interior of the sampling tube are sequentially connected.

[0036] The length of the connecting rod 4 can be adjusted according to sampling needs, or multiple connecting rods 4 can be connected in series to extend the sampling distance.

[0037] The outer wall of the sampling tube 1 can be heated to reduce sample residue.

[0038] The mesh size of the filter 10 is determined by the properties of the fermented grains and is replaced once for each sample.

[0039] After the headspace sampling device is inserted into the mash, when sampling, the sampling pump of the analyzer in the sampling tube 1 draws air, and the ambient gas enters the sample air chamber 12 along the connecting rod airway 3, the connecting rod air chamber 5, and the sampling head airway 7. The gas components of the mash sample continuously evaporate into the sample air chamber 12. Driven by the airflow, the sample gas passes through the filter element 11, along the sampling head air chamber 8 and the sampling tube 1, and then enters the analyzer to achieve in-situ deep sampling.

[0040] Example 2

[0041] The analytical instrument is an ion mobility spectrometer, which detects the alcohol content in the fermented mash online by inserting the headspace sampling device of Example 1 into three identical fermented mash samples 3#, 5#, and 7#. As the insertion depth changes, the alcohol content in the mash increases continuously, and the content of other substances decreases. This further illustrates that the stacked fermented mash has the characteristics of layered fermentation.

[0042] Example 3

[0043] The analytical instrument is an ion mobility spectrometer. The ion mobility spectrometer detects sample 3#. The sampling head of the headspace sampling device in Example 1 is kept away from the surface of the piled mash and inserted into the mash pile. Other collected samples are tested after being diluted 20 times with clean air. The test spectra are compared. The sampling head is directly inserted into the mash. The types of substances detected are relatively rich and the content is relatively high.

[0044] The above contents are further detailed descriptions of the present invention in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, they can also make several substitutions or modifications to these described embodiments without departing from the concept of the present invention, and these substitutions or modifications should be regarded as belonging to the protection scope of the present invention.

Claims

1. An in-situ headspace sampling device for fermented grains detection, characterized in that: It includes a sampling tube, a handle, a connecting rod, a headspace sampling head and a sampling head cover; One end of the sampling tube is connected to the analytical instrument or the sampling bottle, and the other end passes through the handle and the connecting rod in sequence and is connected to the head space sampling head; the head space sampling head is connected to the head cover; The headspace sampling head is a hollow cylindrical structure with a protrusion in the middle. The headspace sampling head becomes thicker at one end toward the sampling head cover to form a sampling head air chamber, and the other end is inserted into the sampling tube. The sampling head air chamber is connected to the end of the sampling head cover toward the sampling head cover, and the sampling head air passages are evenly distributed around the headspace sampling head. The sampling head cover is a cylindrical structure with a hollow center and a triangular arrow-shaped front end. A plurality of long hollow concave areas are evenly distributed on the cylindrical structure of the sampling head cover. A filter screen is covered on the outside of the area. The rear end of the sampling head cover is connected to the head space sampling head. The head space sampling head has one end of a filter element inserted into the center of the sampling head cover, and a sample air chamber is formed between the front end of the filter element and the inside of the sampling head cover. The connecting rod is a hollow cylinder with a thick end, a thin end connected to a hollow cylindrical handle, and a thick end connected to a headspace sampling head, and a connecting rod air chamber is formed between the sampling heads; The gap between the sampling tube, the handle and the connecting rod forms a connecting rod airway; The connecting rod air channel, the connecting rod air chamber, the sampling head air channel, the sample air chamber, the sampling head air chamber, and the interior of the sampling tube are sequentially connected.

2. The device according to claim 1, characterized in that: The connecting rod is provided with a plurality of connecting rods connected in series.

3. The device according to claim 1, characterized in that: The length of the connecting rod is 0.2-3m.

4. The device according to claim 1, characterized in that: A heating device is arranged on the outer wall of the sampling tube.

5. The device according to claim 1, characterized in that: The filter mesh number is 100-1000.

6. The device according to claim 1, characterized in that: A filter fixing rib is respectively placed on both ends of the filter to firmly fix the filter on the sampling head cover.

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