White spirit alcoholic strength rapid detection device and method based on fluorescent indicator and smart phone

Abstract

The invention discloses a device and a method for rapidly detecting the alcoholic strength of white spirit based on a fluorescent indicator and a smart phone. The method comprises the following specific steps: firstly, preparing a fluorescent indicator stock solution; then, preparing a series of alcohol standard solutions with the alcoholic strength of 10-90%, adding the fluorescent indicator stock solution, photographing and recording fluorescent pictures of all samples by using a smart phone under the irradiation of an ultraviolet light source, and establishing a linear curve between the color channel ratio R / B and the alcoholic strength; and finally, adding the fluorescent indicator stock solution into a white spirit sample to be detected, obtaining a fluorescent picture, and calculating the alcoholic strength of the white spirit sample to be detected by utilizing the established linear curve. According to the method, the alcoholic strength is indirectly measured by using the chromaticity difference of the fluorescent indicator in samples with different alcoholic strength, and the method has the advantages of wide measurement range, small background interference, simplicity and convenience in detection operation and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of alcohol content determination in wine, and in particular to a device and method for rapid detection of alcohol content in liquor based on fluorescence and a smart phone. Background Art

[0002] Alcohol content is an important indicator for measuring the quality of liquor. Accurate and rapid determination of alcohol content is crucial to ensuring product quality and safety. It is also of great significance for manufacturers to control alcohol content and maintain consumer safety. Existing alcohol content detection methods include density bottle method, alcohol meter method, gas chromatography and digital density meter method, which have high detection accuracy, but still have shortcomings such as complex sample pretreatment and cumbersome detection process. Therefore, it is urgent to develop an alcohol content detection method that is easy to operate, fast and accurate.

[0003] Fluorescence detection technology is widely used due to its advantages such as short response time and high sensitivity. Curcumin is the main component of turmeric, a plant of the ginger family. It is a natural fluorescent material with a wide source and bio-friendly. In recent years, smartphones, as a functional mobile device that is simple to operate and easy to carry, have provided new development opportunities for rapid real-time analysis and detection. The digital camera in a smartphone can act as a detector to convert images into the three primary colors RGB (red, green, and blue) of the visible spectrum, thereby determining the alcohol content of liquor. Compared with traditional analytical methods that require relatively complex instruments, smartphones have the advantages of fast analysis speed, low cost, and portability, providing a certain impetus for the realization of real-time quantitative on-site analysis in liquor.

[0004] However, smartphone photography is affected by environmental conditions. Lighting conditions, shooting angles, and background colors can all affect the test results. Combining fluorescence detection technology with smartphones not only helps reduce the impact of the external environment, but also allows smartphones to identify the fluorescence color changes in different samples and convert them into RGB values, establish a linear relationship between alcohol content and RGB values, and quickly and effectively achieve the purpose of real-time quantitative on-site analysis of alcohol content. Therefore, it is of certain application value to develop a simple, fast, stable, highly selective and sensitive method for detecting alcohol content in wine based on smartphones, which has a wide range of applications.

[0005] At present, there has been no public report on the use of natural fluorescence combined with smartphones to determine the alcohol content in wine. Summary of the invention

[0006] In view of the above technical problems existing in the prior art, the object of the present invention is to provide a method for detecting the alcohol content in liquor based on a fluorescent indicator.

[0007] In order to achieve the purpose, the present invention adopts the following technical scheme:

[0008] The present invention firstly provides a device for rapid detection of alcohol content of liquor based on a fluorescent indicator and a smart phone, and the device has the structural characteristics of comprising a housing, a sample pool and an ultraviolet light source.

[0009] The shell is made of a light-proof material, and a cavity is formed inside the shell to be isolated from external light. In actual configuration, the shell is preferably made of a light-proof and non-reflective black material.

[0010] The sample pool can be detachably installed in the cavity, and each sample is limited in the sample pool.

[0011] An ultraviolet light source irradiating toward the sample pool is provided in the shell facing the sample pool, and a through detection window is provided on the shell and the ultraviolet light source facing the sample pool, and a filter is provided in the detection window to cover the cross section; in actual setting, the ultraviolet light source is preferably an array LED light board with a voltage of 3.0-3.6V and an emission wavelength of 365nm; the light source switch of the ultraviolet light source is preferably provided outside the shell.

[0012] The smart phone can be detachably limited and installed outside the housing to cover the detection window. Its camera faces the detection window and can clearly capture images of each sample in the sample pool through the detection window.

[0013] Furthermore, the sample pool is of a drawer-type structure, and a sample pool track is correspondingly arranged in the outer shell; the sample pool is slidably mounted on the sample pool track, and a sliding pair is formed therebetween to support the sample pool to be fully inserted into the cavity or fully withdrawn out of the cavity.

[0014] Furthermore, an end plate with an outer convex handle is fixedly provided at the outer end of the sample pool, and a sample pool entrance and exit is correspondingly opened at a position corresponding to the end plate on the housing; when the sample pool is fully inserted into the cavity, the end plate just covers the sample pool entrance and exit. In actual configuration, the end plate can be embedded in the sample pool entrance and exit and just covers the sample pool entrance and exit.

[0015] Furthermore, mobile phone slots are provided on the outside of the shell at both sides of the detection window, and the smart phone is inserted into the mobile phone slots and is installed and limited with the shell.

[0016] Furthermore, the shell is in the shape of a hollow quadrangular prism, and the sample pool is inserted into the cavity by sliding fit from the bottom of one side of the shell; the top plate of the shell is a detachable structure, the ultraviolet light source is installed and fixed to the bottom of the top plate, and the detection window passes through the top plate and the ultraviolet light source; the mobile phone slot is fixed on the top of the top plate.

[0017] The present invention also provides a method for rapid detection of alcohol content of liquor based on a fluorescent indicator and a smart phone, which is performed using the above detection device and includes the following steps:

[0018] 1) Preparation of fluorescent indicator stock solution: dissolving the fluorescent indicator in anhydrous ethanol to prepare a fluorescent indicator stock solution, and placing it in the dark for standby use;

[0019] 2) preparing a standard working curve: mixing anhydrous ethanol and water, and preparing a series of alcohol standard solutions with an alcohol content of 10-90% at even intervals; adding the fluorescent indicator stock solution to each alcohol standard solution, and mixing them evenly at room temperature; adding an appropriate amount of each sample to a centrifuge tube, and then placing the centrifuge tube in the sample pool of the detection device, under the irradiation of an ultraviolet light source, taking a photo with a smart phone to record the fluorescence image of each sample, and then using an image processing application of the smart phone to analyze the RGB value of the fluorescence image of each sample, establishing a linear curve between the color channel ratio R / B and the alcohol content, and obtaining a linear equation I=aC+b after fitting, wherein C is the alcohol content and I is the R / B value;

[0020] 3) Determine the alcohol content: add the fluorescent indicator stock solution to the liquor sample to be tested, mix evenly at room temperature, add an appropriate amount of the sample to a centrifuge tube, and then place the centrifuge tube in the sample pool of the detection device. Under ultraviolet light, use a smart phone to take a photo to record the fluorescent image of the sample, and then use the image processing application of the smart phone to analyze the RGB value of the fluorescent image of the sample. Substitute the obtained data into the linear equation of step 2) to calculate the alcohol content of the liquor sample to be tested.

[0021] Furthermore, the fluorescent indicator described in step 1) is curcumin, which has the characteristics of high luminescence intensity, high photochemical stability, wide source, and bio-friendliness.

[0022] Further: in step 1), the concentration of the fluorescent indicator stock solution is 250.0 μM; in step 2) and step 3), the volume ratio of the fluorescent indicator stock solution to the alcohol standard solution or the liquor sample to be tested is 1:24, and the total volume of the sample after adding the fluorescent indicator stock solution is 2.50 mL, wherein the concentration of the fluorescent indicator is 10.0 μM.

[0023] Further: In step 2), the alcohol content of a series of prepared alcohol standard solutions ranges from 10% to 90%. Within this alcohol content range, there is a good linear response between the R / B value of the sample fluorescence image and the ethanol concentration, and a linear equation is obtained by fitting.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] 1. The present invention uses a natural fluorescent indicator combined with a smart phone to detect the alcohol content in liquor. The method utilizes the differences in fluorescence intensity of the natural fluorescent indicator and sample chromaticity caused by different alcohol contents in liquor, and analyzes and processes the data through a smart phone, thereby indirectly realizing the determination of the alcohol content. The method is simple to operate, has a wide range of alcohol content determination, less interference, and simple detection.

[0026] 2. The cavity inside the shell of the detection device provided by the present invention is isolated from the external ambient light, providing a detection environment for the sample that is not affected by external light conditions. At the same time, an ultraviolet light source placed in the cavity provides stable lighting, which can better ensure the consistency of the light environment in sample detection as one of the factors affecting the detection results, and is beneficial to ensuring the accuracy of the detection results. The present invention has a simple structure and is easy to operate. It uses an easily accessible smart phone as an image acquisition device, and has strong feasibility.

[0027] 3. The fluorescent indicator used in the present invention is curcumin, which is extracted from the rhizome of the plant turmeric and is a natural indicator. The maximum excitation wavelength of the indicator in ethanol is 430nm and the emission wavelength is 550nm. Under the irradiation of ultraviolet light (365nm), the fluorescent indicator emits yellow light. The present invention uses the indicator to detect the alcohol content in liquor. As the alcohol content of the sample increases, the fluorescence intensity of the indicator gradually increases, and after the RGB value is obtained by the color recognition software of the smart phone, the R / B value has a good linear relationship with the alcohol content. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of a rapid detection device for alcohol content of liquor provided in an embodiment;

[0029] Figure 2 This is a disassembled diagram of the internal structure of the rapid detection device for alcohol content of liquor provided in the embodiment;

[0030] Figure 3 is a three-dimensional fluorescence spectrum of the fluorescent indicator stock solution in Example 1;

[0031] Figure 4 The two-dimensional fluorescence intensity change diagram of curcumin in different concentrations of ethanol aqueous solution in Example 2;

[0032] Figure 5 The fluorescence images of curcumin in different concentrations of ethanol-water solution under 365nm ultraviolet light in Example 2 ( Figure 5 (a)) and the linear relationship between the R / B value and the concentration of ethanol-water solution (10-90%) ( Figure 5 (b) in the above);

[0033] Figure 6The three-dimensional fluorescence spectra of curcumin in different liquor samples in Example 4, the labeled alcohol content of the liquors corresponding to (a) to (f) are 75.0%, 42.0%, 56.0%, 42.0%, 56.0%, and 42.0%, respectively;

[0034] Figure 7 This is the fluorescence image of curcumin in different liquor samples under 365nm ultraviolet light in Example 4.

[0035] Numbers in the figure: 1-smartphone, 2-mobile phone slot, 3-light source switch, 4-housing, 5-sample pool entrance and exit, 6-filter, 7-detection window, 8-top plate, 9-ultraviolet light source, 10-sample pool, 11-sample pool track. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the technical solution of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] Unless otherwise specified, the experimental materials and reagents used in the following examples can be obtained from commercial sources. If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in the field or according to the product instructions.

[0038] The curcumin used in the following examples is a standard product from Aladdin.

[0039] The rapid detection device for alcohol content of liquor based on fluorescent indicator and smart phone used in the following examples 1 to 4 is as follows: Figure 1-2 As shown, the structural relationship is as follows: the outer shell 4 is in the shape of a hollow quadrangular prism, and is made of a light-proof and non-reflective black material, forming a light-isolating cavity inside, and its top plate is a detachable structure.

[0040] The sample pool 10 is a drawer-type structure, on which samples are placed in rows and limited by a limiting structure such as a sample slot; a sample pool track 11 is correspondingly arranged in the outer shell 4, and the sample pool 10 is slidably mounted on the sample pool track 11, and is inserted into the cavity by a sliding fit from the bottom of one side of the outer shell 4; an end plate with an outer convex handle is fixedly arranged at the outer end of the sample pool 10, and a sample pool entrance and exit 5 is correspondingly opened at a position corresponding to the end plate on the outer shell 4; when the sample pool 10 is fully inserted into the cavity, the end plate just covers the sample pool entrance and exit 5.

[0041] The array LED light board is installed and fixed to the bottom of the top plate as the ultraviolet light source 9, and irradiates the sample pool 10.

[0042] A through detection window 7 is provided at the center of the housing 4 and the array LED light panel, and a filter is arranged in the detection window 7 to cover the cross section; the smart phone 1 is placed on the top of the housing 4 to shield the detection window 7, and its camera is facing the detection window 7, so that the image of each sample in the sample pool 10 can be clearly captured through the detection window 7; a mobile phone slot 2 is arranged on both sides of the smart phone 1 on the top of the housing 4 to limit the smart phone 1.

[0043] Example 1: Preparation of fluorescent indicator stock solution

[0044] Accurately weigh 1.84 g of curcumin powder and place it in a 20.0 mL volumetric flask, add anhydrous ethanol to dissolve and dilute to the mark, shake well, and prepare a curcumin stock solution with a concentration of 250.0 μM. The resulting solution exhibits strong yellow light emission under ultraviolet light, and the maximum ultraviolet-visible absorption wavelength is at 430 nm. At this excitation wavelength, the maximum fluorescence emission wavelength is 550 nm (see Figure 3 ).

[0045] Example 2: Fluorescence response of fluorescent indicator solution to ethanol concentration in ethanol-water solution

[0046] Prepare ethanol-water mixed solutions with different ethanol concentrations (wherein the ethanol concentrations are 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, and 90%). Take 2.40 mL of solutions with different alcohol concentrations in turn, add 0.1 mL of the fluorescent indicator stock solution prepared in Example 1, mix well at room temperature, analyze the samples using a fluorescence spectrophotometer, and draw a two-dimensional fluorescence signal intensity change diagram of samples with different alcohol concentrations at Ex=430 nm (see Figure 4 ), it can be seen that the fluorescence intensity increases with the increase of alcohol content. Subsequently, a quantitative mixture of different alcohol content solutions with fluorescent indicators was added to a 0.6 mL centrifuge tube, and the centrifuge tube containing the sample was placed in the sample pool of the detection device. Under the irradiation of a 365 nm ultraviolet light source, a smartphone was used to take photos and record the fluorescence images of samples with different alcohol content (see Figure 5 The RGB values ​​of the fluorescence images of each sample were analyzed using an image processing application on a smartphone, and the relationship between the R / B value and the ethanol concentration was plotted (see Figure 5 It can be clearly seen from (b) that with the increase of ethanol concentration, the R / B value gradually increases. At the same time, when the ethanol concentration is in the range of 10%-90%, there is a good linear response between the sample R / B value and the ethanol concentration (R 2=0.984), and the linear equation of alcohol content and color channel R / B value was obtained by fitting: I=0.0130C+0.5403, where C is alcohol content and I is R / B value.

[0047] Example 3: Methodological Investigation

[0048] 1) Precision

[0049] Prepare an ethanol-water mixed solution with an alcohol content of 75%, and then detect its alcohol content as follows: draw 2.40mL of the ethanol-water mixed solution and add 0.1mL of the fluorescent indicator stock solution prepared in Example 1, and mix evenly at room temperature. Take a quantitative sample and add it to a 0.6mL centrifuge tube, place the centrifuge tube containing the sample in the sample pool of the detection device, and take a photo with a smart phone to record its fluorescence picture under the irradiation of a 365nm ultraviolet light source. Use the image processing application of the smart phone to analyze the RGB value of the fluorescence picture of the sample, and calculate the alcohol content of the sample by the R / B value in combination with the linear equation of Example 2 (Table 1), analyze it 3 times in a row, and calculate RSD=1.3% (n=3), indicating that the method has good precision.

[0050] 2) Repeatability

[0051] Three portions of ethanol-water mixed solutions with an alcohol content of 75% were prepared respectively. The alcohol content was detected according to the method in 1) and the RSD was calculated to be 2.1% (n=3), indicating that the method had good repeatability.

[0052] 3) Stability

[0053] Prepare an ethanol-water mixed solution with an alcohol content of 75%, draw 2.40 mL and add 0.1 mL of the fluorescent indicator stock solution prepared in Example 1, mix well at room temperature, and place at room temperature in the dark. The sample is tested for alcohol content according to the method in 1) at 0, 6, 12, 18, and 24 h, and the RSD is calculated to be 1.8% (n=5), indicating that the method is stable for sample detection results within 24 h.

[0054] 4) Spike recovery rate

[0055] Prepare an ethanol-water mixed solution with an alcohol content of 75%, take 4.0 mL and place it in a 5.0 mL volumetric flask, add anhydrous ethanol to the mark, shake well, and prepare 3 portions in parallel. According to method 1), the alcohol content of the sample was measured and the recovery rate was calculated. The results are shown in Table 1.

[0056] Table 1. Methodology and spike recovery test results

[0057]

[0058] Example 4: Visual detection of alcohol content of actual samples

[0059] 0.1 mL of the fluorescent indicator stock solution prepared in Example 1 was added to 2.4 mL of the liquor samples to be tested with different alcohol contents, and mixed evenly at room temperature. First, a three-dimensional fluorescence analysis was performed on the samples, and three-dimensional fluorescence characteristic spectra of different liquor samples were drawn (see Figure 6 ). Take the quantitative mixed liquor sample solutions of different kinds and add them into 0.6mL centrifuge tubes. Place the centrifuge tubes containing the samples into the sample pool of the detection device. Under the irradiation of ultraviolet light with a wavelength of 365nm, use a smart phone to take pictures and record the fluorescence images of each sample. Figure 7 As shown, it can be seen that the fluorescence image changes with the change of the sample alcohol content. The RGB values ​​of the fluorescence images of different samples are analyzed using the image processing application of the smartphone, and the R / B value of each sample is substituted into the linear equation in step 1) to calculate the alcohol content of the wine sample to be tested. The results are shown in Table 2.

[0060] Table 2. Actual sample test results

[0061]

[0062]

[0063] The above description is only an exemplary embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A rapid detection device for alcohol content of liquor based on a fluorescent indicator and a smart phone, characterized in that: It comprises a housing (4), a sample pool (10) and an ultraviolet light source (9); The housing (4) is made of a light-proof material, and forms a cavity therein that is isolated from external light; The sample pool (10) can be detachably installed in the cavity, and each sample is limited in the sample pool (10); The housing (4) is provided with the ultraviolet light source (9) facing the sample pool (10) and irradiating toward the sample pool (10), and a through detection window (7) is provided on the housing (4) and the ultraviolet light source (9) facing the sample pool (10), and a filter is provided in the detection window (7) covering the cross section; The smart phone (1) is detachably limited and mounted outside the housing (4) to shield the detection window (7), and its camera faces the detection window (7), and can clearly capture images of each sample in the sample pool (10) through the detection window (7).

2. According to claim 1, a rapid detection device for alcohol content of liquor based on a fluorescent indicator and a smart phone is characterized in that: The sample pool (10) is of a draw-plate structure, and a sample pool track (11) is correspondingly arranged in the housing (4); the sample pool (10) is slidably mounted on the sample pool track (11), and a sliding pair is formed therebetween to support the sample pool (10) to be fully inserted into the cavity or fully withdrawn out of the cavity.

3. A rapid detection device for alcohol content of liquor based on a fluorescent indicator and a smart phone according to claim 2, characterized in that: An end plate having an outer convex handle is fixedly provided at the outer end of the sample pool (10), and a sample pool entrance and exit (5) is correspondingly provided on the housing (4) at a position corresponding to the end plate; when the sample pool (10) is completely inserted into the cavity, the end plate just covers the sample pool entrance and exit (5).

4. A rapid detection device for alcohol content of liquor based on a fluorescent indicator and a smart phone according to any one of claims 1 to 3, characterized in that: The housing (4) is provided with mobile phone slots (2) on both sides of the detection window (7), and the smart phone (1) is inserted into the mobile phone slots (2) and is installed and limited with the housing (4).

5. A rapid detection device for alcohol content of liquor based on a fluorescent indicator and a smart phone according to claim 4, characterized in that: The housing (4) is in the shape of a hollow quadrangular prism, and the sample pool (10) is inserted into the cavity by sliding fit from the bottom of one side of the housing (4); The top plate of the housing (4) is a detachable structure; the ultraviolet light source (9) is fixedly mounted to the bottom of the top plate; the detection window (7) is opened through the top plate and the ultraviolet light source (9); and the mobile phone slot (2) is fixedly mounted on the top of the top plate.

6. A method for rapid detection of alcohol content of liquor based on a fluorescent indicator and a smart phone, characterized in that: The method is carried out using the detection device according to any one of claims 1 to 5, comprising the following steps: 1) Preparation of fluorescent indicator stock solution: dissolving the fluorescent indicator in anhydrous ethanol to prepare a fluorescent indicator stock solution, and placing it in the dark for standby use; 2) Preparation of standard working curve: anhydrous ethanol and water are mixed to prepare a series of alcohol standard solutions with an alcohol content of 10-90%; the fluorescent indicator stock solution is added to each alcohol standard solution and mixed evenly at room temperature; an appropriate amount of each sample is placed in a sample pool of the detection device, and under ultraviolet light, a smartphone is used to take a photo to record the fluorescence image of each sample, and then the RGB value of the fluorescence image of each sample is analyzed using an image processing application of the smartphone, and a linear curve between the color channel ratio R / B and the alcohol content is established, and a linear equation I=aC+b is obtained by fitting, wherein C is the alcohol content and I is the R / B value; 3) Determination of alcohol content: Add the fluorescent indicator stock solution to the liquor sample to be tested, mix evenly at room temperature, take an appropriate amount of the sample and place it in the sample pool of the detection device, and use a smart phone to take a photo under ultraviolet light to record the fluorescent image of the sample, and then use the image processing application of the smart phone to analyze the RGB value of the fluorescent image of the sample, and substitute the obtained data into the linear equation of step 2) to calculate the alcohol content of the liquor sample to be tested.

7. A method for rapid detection of alcohol content of liquor based on a fluorescent indicator and a smart phone according to claim 6, characterized in that: The fluorescent indicator described in step 1) is curcumin.

8. The method for rapid detection of alcohol content of liquor based on a fluorescent indicator and a smart phone according to claim 6, characterized in that: In step 1), the concentration of the fluorescent indicator stock solution is 250.0 μM; in step 2) and step 3), the volume ratio of the fluorescent indicator stock solution to the alcohol standard solution or the liquor sample to be tested is 1:24, and the total volume of the sample after adding the fluorescent indicator stock solution is 2.50 mL, wherein the concentration of the fluorescent indicator is 10.0 μM.

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