Rapid detection method for evaluating taste of drinking water by using electronic tongue

Abstract

The invention discloses a rapid detection method for evaluating the taste of drinking water by using an electronic tongue. The method comprises the following steps: preparing a reference water sample; establishing a database, establishing a reference water sample database by using an electronic tongue, and establishing a data analysis model according to analysis requirements; testing the taste of the reference water sample prepared in the step S1 by using an electronic tongue; analyzing the tested water sample by using the established data analysis model; and testing according to the reference water sample prepared in the step S1. The electronic tongue is used for establishing a database of a reference water sample, the taste of a water sample to be detected is analyzed through a principal component analysis (PCA) model, a discriminant factor analysis (DFA) model, a statistical mass analysis (SQC) model or a soft independent modeling analysis (SIMCA) model and the like, and the method has the characteristics of short detection time, simplicity in operation, high sensitivity, high reliability and the like.

Description

[Technical field]

[0001] The present invention relates to the technical field of drinking water taste, and in particular to a method for rapidly detecting the taste of drinking water by establishing an evaluation system using an electronic tongue. [Background technology]

[0002] The taste of drinking water is the indicator that consumers pay most attention to when it comes to drinking water and water purifiers, and the quality of the taste of drinking water is generally evaluated by tasters. However, the reproducibility of the evaluation results of manual drinking water evaluation personnel is poor, and the evaluation results are easily affected by factors such as the taster's personal living habits, taste preferences, and physiological and psychological state during the evaluation. The evaluation process is cumbersome and the labor cost is high. In addition, the safety of unknown water samples cannot be quickly identified, and manual evaluation will pose certain potential safety risks to tasters. Therefore, exploring a drinking water evaluation method based on sensory evaluation equipment can not only improve the evaluation efficiency of drinking water taste, but also provide support for corporate research and development. [Summary of the invention]

[0003] The present invention aims at the objective problems existing in the existing industry, provides an ideal pure water and mineral water as reference water samples, uses an electronic tongue to establish a database of reference water samples, and analyzes the taste of the water samples to be tested through models such as principal component analysis (PCA), discriminant factor analysis (DFA), statistical quality analysis (SQC) or soft independent modeling analysis (SIMCA), so as to screen out the most competitive water sample formula. It has the characteristics of short detection time, simple operation, high sensitivity and strong reliability.

[0004] The present invention relates to a rapid detection method for evaluating the taste of drinking water using an electronic tongue, which is characterized by comprising the following steps:

[0005] S1: Prepare reference water samples. Select or prepare reference water samples according to the category of drinking water or taste evaluation needs;

[0006] S2: Establish a database, use the electronic tongue to establish a reference water sample database, and establish a data analysis model according to analysis needs;

[0007] S3: Using an electronic tongue to test the taste of the reference water sample prepared in step S1;

[0008] S4: Analyze the tested water sample using the established data analysis model;

[0009] Prepare reference water samples according to S1, select / prepare ideal water samples for evaluation, and keep reference water samples and tested water samples in a sealed state at room temperature for testing.

[0010] In each test, use the same batch of reference water samples to make at least 3 water samples with different numbers. Each water sample with different numbers in the same group is tested 7 times. The 3 water samples with different numbers in the same group are placed at the beginning, middle and end of the test sequence respectively.

[0011] The model established by the tested water samples and reference water samples of the same batch as above is used for analysis. The data model is used to analyze the similarity and discreteness of the tested water samples and the reference water samples, so as to judge the taste of the tested water samples.

[0012] According to S1, two types of reference water samples need to be prepared, including pure water reference water samples and mineral water reference water samples.

[0013] The formula of the pure water reference water sample is:

[0014] Sodium chloride: 3.5-5.5 mg / L;

[0015] Calcium chloride: 2.0-3.0 mg / L;

[0016] Magnesium sulfate: 2.0-3.0 mg / L;

[0017] Saccharin sodium: 3.0-5.0 mg / L;

[0018] Sodium glutamate: 30-40 mg / L;

[0019] Quinine hydrochloride: 10-12 mg / L;

[0020] Citric acid: 40-50 mg / L;

[0021] The formula of the mineral water reference sample is:

[0022] Sodium chloride: 3.5-5.5 mg / L;

[0023] Calcium chloride: 30-35 mg / L;

[0024] Sodium bicarbonate: 2.0-3.0 mg / L;

[0025] Magnesium sulfate: 15-20 mg / L;

[0026] Saccharin sodium: 5.0-7.0 mg / L;

[0027] Sodium glutamate: 30-40 mg / L;

[0028] Quinine hydrochloride: 10-12 mg / L;

[0029] Citric acid: 40-50 mg / L;

[0030] The method for preparing two types of reference water samples comprises the following steps:

[0031] Step 1: Weigh each component in the reference pure water sample formula and the reference mineral water sample formula according to the required amount, and fully dissolve them in first-class water (need to meet GB6682 standard);

[0032] Step 2: Mix the above dissolved solution and oscillate ultrasonically for 10 minutes;

[0033] Step 3: Place the uniformly mixed solution in step 2 into a glass bottle and seal it, and keep it at a constant temperature under standard room temperature;

[0034] Step 4: Mix the solutions in the previous step and adjust the pH value of the solution with 1 mol / L potassium dihydrogen phosphate and 1 mol / L potassium hydrogen phosphate, wherein the pH value of pure water is adjusted to 6.85 and the pH value of mineral water is adjusted to 7.05; and the solution is kept at a constant temperature of 25°C and then fixed to volume with first-grade water. The solution is marked as solution D.

[0035] Step 5: Solution D in the previous step can be packaged in glass bottles and stored for long-term use after sterilization. After sterilization, the solution should be stored in a 4°C refrigerator away from light and marked as solution F.

[0036] Step 6: Return solution D or solution F to room temperature, and use the electronic tongue to analyze solution D or solution F to establish a database;

[0037] Step 7: Use the electronic tongue to analyze the water sample, use the database to establish a data analysis model and analyze the test results;

[0038] Step 8: Solution D or F can also be used by sensory panelists to evaluate water quality samples. Solution D or F is stored in a 4°C refrigerator away from light. Each time a sensory analysis of a water sample is performed, Solution F and the tested water sample are kept at room temperature. The sensory panelists evaluate the taste of the tested water sample using Solution F as a reference. A water sample with a comprehensive score better than Solution F is deemed to have a better taste than Solution F. A water sample with a comprehensive score worse than Solution F is deemed to have a worse taste than Solution F. A water sample with a score consistent with Solution F is deemed to have a consistent taste with Solution F. The closer the score is to the taste of Solution F, the more similar the tested water sample and Solution F are.

[0039] The container for dispensing solution D in step 5 is an ampoule bottle, and plastic or silicone rubber bottles shall not be used.

[0040] The sterilization method described in step 5 is irradiation sterilization, pulse electric field sterilization, microwave sterilization, and static pressure sterilization.

[0041] By providing an ideal pure water and mineral water as reference water samples, the electronic tongue is used to establish a database of reference water samples and analyze the taste of the water samples through models such as principal component analysis (PCA), discriminant factor analysis (DFA), statistical quality analysis (SQC) or soft independent modeling analysis (SIMCA), so as to screen out the most competitive water sample formula. It has the characteristics of short detection time, simple operation, high sensitivity and strong reliability.

Brief Description of the Drawings

[0042] Figure 1 It is a PCA diagram of the principal component analysis of the water sample involved in the present invention;

[0043] Figure 2 It is a PCA three-dimensional graph of the principal component analysis of the water sample involved in the present invention;

[0044] Figure 3 It is a DFA diagram of the water sample discriminant factor analysis involved in the present invention;

[0045] Figure 4 It is the SIMCA diagram of the water sample soft modeling analysis involved in the present invention. [Specific implementation method]

[0046] The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments, examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0047] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0048] The rapid detection method for evaluating the taste of drinking water using an electronic tongue according to the present invention is characterized by comprising the following steps:

[0049] S1: Prepare reference water samples. Select or prepare reference water samples according to the category of drinking water or taste evaluation needs;

[0050] S2: Establish a database, use the electronic tongue to establish a reference water sample database, and establish a data analysis model according to analysis needs;

[0051] S3: Using an electronic tongue to test the taste of the reference water sample prepared in step S1;

[0052] S4: Analyze the tested water sample using the established data analysis model;

[0053] Prepare reference water samples according to S1, select / prepare ideal water samples for evaluation, and keep reference water samples and tested water samples in a sealed state at room temperature for testing.

[0054] In each test, use the same batch of reference water samples to make at least 3 water samples with different numbers. Each water sample with different numbers in the same group is tested 7 times. The 3 water samples with different numbers in the same group are placed at the beginning, middle and end of the test sequence respectively.

[0055] The model established by the tested water samples and reference water samples of the same batch as above is used for analysis. The data model is used to analyze the similarity and discreteness of the tested water samples and the reference water samples, so as to judge the taste of the tested water samples.

[0056] According to S1, two types of reference water samples need to be prepared, including pure water reference water samples and mineral water reference water samples.

[0057] The formula of the pure water reference water sample is:

[0058] Sodium chloride: 3.5-5.5 mg / L;

[0059] Calcium chloride: 2.0-3.0 mg / L;

[0060] Magnesium sulfate: 2.0-3.0 mg / L;

[0061] Saccharin sodium: 3.0-5.0 mg / L;

[0062] Sodium glutamate: 30-40 mg / L;

[0063] Quinine hydrochloride: 10-12 mg / L;

[0064] Citric acid: 40-50 mg / L;

[0065] The formula of the mineral water reference sample is:

[0066] Sodium chloride: 3.5-5.5 mg / L;

[0067] Calcium chloride: 30-35 mg / L;

[0068] Sodium bicarbonate: 2.0-3.0 mg / L;

[0069] Magnesium sulfate: 15-20 mg / L;

[0070] Saccharin sodium: 5.0-7.0 mg / L;

[0071] Sodium glutamate: 30-40 mg / L;

[0072] Quinine hydrochloride: 10-12 mg / L;

[0073] Citric acid: 40-50 mg / L;

[0074] The method for preparing two types of reference water samples comprises the following steps:

[0075] Step 1: Weigh each component in the reference pure water sample formula and the reference mineral water sample formula according to the required amount, and fully dissolve them in first-class water (need to meet GB6682 standard);

[0076] Step 2: Mix the above dissolved solution and oscillate ultrasonically for 10 minutes;

[0077] Step 3: Place the uniformly mixed solution in step 2 into a glass bottle and seal it, and keep it at a constant temperature under standard room temperature;

[0078] Step 4: Mix the solutions in the previous step and adjust the pH value of the solution with 1 mol / L potassium dihydrogen phosphate and 1 mol / L potassium hydrogen phosphate, wherein the pH value of pure water is adjusted to 6.85 and the pH value of mineral water is adjusted to 7.05; and the solution is kept at a constant temperature of 25°C and then fixed to volume with first-grade water. The solution is marked as solution D.

[0079] Step 5: Solution D in the previous step can be packaged in glass bottles and stored for long-term use after sterilization. After sterilization, the solution should be stored in a 4°C refrigerator away from light and marked as solution F.

[0080] Step 6: Return solution D or solution F to room temperature, and use the electronic tongue to analyze solution D or solution F to establish a database;

[0081] Step 7: Use the electronic tongue to analyze the water sample, use the database to establish a data analysis model and analyze the test results;

[0082] Step 8: Solution D or F can also be used by sensory panelists to evaluate water quality samples. Solution D or F is stored in a 4°C refrigerator away from light. Each time a sensory analysis of a water sample is performed, Solution F and the tested water sample are kept at room temperature. The sensory panelists evaluate the taste of the tested water sample using Solution F as a reference. A water sample with a comprehensive score better than Solution F is deemed to have a better taste than Solution F. A water sample with a comprehensive score worse than Solution F is deemed to have a worse taste than Solution F. A water sample with a score consistent with Solution F is deemed to have a consistent taste with Solution F. The closer the score is to the taste of Solution F, the more similar the tested water sample and Solution F are.

[0083] The container for dispensing solution D in step 5 is an ampoule bottle, and plastic or silicone rubber bottles shall not be used.

[0084] The sterilization method described in step 5 is irradiation sterilization, pulse electric field sterilization, microwave sterilization, and static pressure sterilization. Specific embodiment 1:

[0086] S1: Prepare reference water samples of purified water. Select or prepare reference water samples according to the type of drinking water or taste evaluation requirements;

[0087] S2: Establish a database, use the electronic tongue to establish a reference water sample database, and establish a data analysis model according to analysis needs; use the electronic tongue to perform principal component analysis (PCA), discriminant factor analysis (DFA), statistical quality analysis (SQC) or soft independent modeling analysis (SIMCA).

[0088] S3: Using an electronic tongue to test the taste of the pure water reference water sample prepared in step S1;

[0089] S4: Analyze the tested water sample using the established data analysis model;

[0090] Preparation of pure water sample to be tested:

[0091] 1. Weigh 5 mg of sodium chloride, 3.0 mg of calcium chloride, 3.0 mg of magnesium sulfate, 5 mg / L of sodium saccharin, and 50 mg of sodium glutamate, and dissolve them in 50 mL of first-grade water.

[0092] 2. Transfer the above solution to a glass beaker, mix well, and oscillate ultrasonically for 10 minutes. Place the solution in a sealed glass bottle and keep the temperature at 25°C.

[0093] 3. Use 1 mol / L potassium dihydrogen phosphate and 1 mol / L potassium hydrogen phosphate to adjust the pH value of the solution to 6.85 and then adjust the volume to 1.00 L.

[0094] 4. Dispense the solution from the previous step into glass bottles.

[0095] 5. Sterilize the solution in the previous step by radiation sterilization. After sterilization, store the solution in a 4°C refrigerator away from light and mark it as solution D00001.

[0096] 6. Return solution D0001 to room temperature and use the electronic tongue to analyze and establish a database.

[0097] 7. Take four samples to be tested and mark them as C00018, C00032,

[0098] D00002 and D00004, using electronic tongue to analyze the tested water samples C00018, C00032,

[0099] D00002, D00004, the water samples were analyzed using the database and analysis model, and the analysis results are as follows:

[0100] According to the PCA analysis results of the electronic tongue, Figure 1 It can be seen that the sum of the contribution rates of principal components 1 and 2 reaches 90.09%, indicating that the analysis results can well reflect the true results of the samples. The recognition factor is 0.01, indicating that there are similarities between different analyzed samples; according to the DFA analysis of water samples, water samples C00018, C00032, and D00002 can be well distinguished, and water samples D00001 and D00004 have certain similarities; an acceptable domain is established with D00001 as the reference water sample. As shown in the figure, water sample D00004 falls into the acceptable domain of water sample D00001, indicating that water samples D00004 and water sample D00001 have similar tastes, water samples C00018, C00032, and D00002 do not fall into the acceptable domain of water sample D00001, and water samples C00018, C00032, D00002 are not similar to water sample D00001, and the taste is quite different from that of water sample D00001.

[0101] In electronic tongue technology, principal component analysis (PCA) is a commonly used data processing method for dimensionality reduction and data visualization. Through PCA analysis, the original data can be projected into a new coordinate system. The axes in this new coordinate system are called "principal components" and they are orthogonal to each other.

[0102] Among them, principal component 1 (PC1): This is the direction with the largest data variance, that is, among all possible directions, the data varies the most in this direction, and it represents the main source of variation in the data.

[0103] Principal component 2 (PC2): This is the direction with the second largest data variance in the direction orthogonal (i.e. vertical) to principal component 1. Principal component 2 captures the second important source of data variation, which helps us understand other variation patterns beyond principal component 1.

[0104] and Figure 2 It is a three-dimensional diagram of PAC analysis. Figure 3 is the DFA diagram of water sample discriminant factor analysis; and Figure 4 This is the SIMCA diagram of water sample soft modeling analysis. The closer the positions of the tested water sample and the reference water sample in the diagram are, the more similar they are. Different colors represent points of different water samples.

[0105] Solution D or F can also be used by sensory assessors to evaluate water quality samples. Solution D or F is stored in a 4°C refrigerator away from light. Each time a sensory analysis of a water sample is performed, solution F and the tested water sample are kept at a constant temperature at room temperature. The sensory assessors evaluate the taste of the tested water sample using solution F as a reference. A water sample with a comprehensive score better than solution F is deemed to have a better taste than solution F; a water sample with a comprehensive score worse than solution F is deemed to have a worse taste than solution F; a water sample with a score consistent with solution F is deemed to have a consistent taste with solution F. The closer the taste of the tested water sample is to that of solution F, the more similar the tested water sample and solution F are.

[0106] The scoring table is established according to the feelings of the sensory reviewers as follows:

[0107]

[0108] Table 1 Water sample taste rating table

[0109] Using reference water sample D00001 as a reference, sensory assessors were organized to evaluate the tested water samples C00018, C00032, D00002, and D00004. The scoring table was implemented with reference to Table 1. The evaluation results are shown in Table 2:

[0110] Water sample number D00001 D00002 D00004 C00018 C00032 Average water sample score 2.4 2.9 2.2 3.2 3.9

[0111] Table 2 Evaluation results of personnel for tested water samples

[0112] As shown in Table 2, the evaluation result of water sample D00004 among the tested water samples is closer to the reference water sample D00001. The taste of the evaluated water samples is ranked from good to bad as follows: D00004, D00001, D00002, C00018, and C00032.

[0113] The present invention provides an ideal pure water and mineral water as reference water samples, uses an electronic tongue to establish a database of reference water samples, and analyzes the taste of the water samples to be tested through models such as principal component analysis (PCA), discriminant factor analysis (DFA), statistical quality analysis (SQC) or soft independent modeling analysis (SIMCA), so as to screen out the most competitive water sample formula in the market. The invention has the characteristics of short detection time, simple operation, high sensitivity, strong reliability, etc.

[0114] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention is disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes by using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments according to the technology of the present invention are within the scope of the technical solution of the present invention without departing from the content of the technical solution of the present invention.

Claims

1. A rapid detection method for evaluating the taste of drinking water using an electronic tongue, characterized in that: The following steps are involved: S1: Prepare reference water samples. Select or prepare reference water samples according to the category of drinking water or taste evaluation needs; S2: Establish a database, use the electronic tongue to establish a reference water sample database, and establish a data analysis model according to analysis needs; S3: Using an electronic tongue to test the taste of the reference water sample prepared in step S1; S4: Analyze the tested water samples using the established data analysis model.

2. The rapid detection method for evaluating the taste of drinking water using an electronic tongue according to claim 1, characterized in that: Prepare reference water samples according to S1, select / prepare ideal water samples for evaluation, and keep reference water samples and tested water samples in a sealed state at room temperature for testing.

3. The rapid detection method for evaluating the taste of drinking water using an electronic tongue according to claim 2, characterized in that: In each test, use the same batch of reference water samples to take at least 3 water samples with different numbers in the same group. Each water sample with different numbers in the same group is tested 7 times. The 3 water samples with different numbers in the same group are placed at the beginning, middle and end of the test sequence respectively.

4. The rapid detection method for evaluating the taste of drinking water using an electronic tongue according to claim 3, characterized in that: The model established by the tested water samples and reference water samples of the same batch as above is used for analysis. The data model is used to analyze the similarity and discreteness of the tested water samples and the reference water samples, so as to judge the taste of the tested water samples.

5. The rapid detection method for evaluating the taste of drinking water using an electronic tongue according to claim 1, characterized in that: According to S1, two types of reference water samples need to be prepared, including pure water reference water samples and mineral water reference water samples. The formula of the pure water reference water sample is: Sodium chloride: 3.5-5.5 mg / L; Calcium chloride: 2.0-3.0 mg / L; Magnesium sulfate: 2.0-3.0 mg / L; Saccharin sodium: 3.0-5.0 mg / L; Monosodium glutamate: 30-40 mg / L; Quinine hydrochloride: 10-12 mg / L; Citric acid: 40-50mg / L; The formula of the mineral water reference sample is: Sodium chloride: 3.5-5.5 mg / L; Calcium chloride: 30-35 mg / L; Sodium bicarbonate: 2.0-3.0 mg / L; Magnesium sulfate: 15-20 mg / L; Saccharin sodium: 5.0-7.0 mg / L; Monosodium glutamate: 30-40 mg / L; Quinine hydrochloride: 10-12mg / L; Citric acid: 40-50mg / L.

6. The rapid detection method for evaluating the taste of drinking water using an electronic tongue according to claim 5, characterized in that: The method for preparing two types of reference water samples comprises the following steps: Step 1: Weigh each component in the reference pure water sample formula and the reference mineral water sample formula according to the required amount, and use first-class water. Here, the first-class water used meets the GB6682 standard and is fully dissolved; Step 2: Mix the above dissolved solution and oscillate ultrasonically for 10 minutes; Step 3: Place the uniformly mixed solution in step 2 into a glass bottle and seal it, and keep it at a constant temperature under standard room temperature; Step 4: Mix the solution in the previous step and adjust the pH value of the solution with 1 mol / L potassium dihydrogen phosphate and 1 mol / L potassium hydrogen phosphate, wherein the pH value of pure water is adjusted to 6.85 and the pH value of mineral water is adjusted to 7.05; and the solution is kept constant at 25°C and then fixed to volume with first-class water. The solution is marked as solution D; Step 5: The solution D in the previous step can be packaged in glass bottles and stored for long-term use after sterilization. After sterilization, the solution is stored in a refrigerator at 4°C away from light and marked as solution F; Step 6: Return solution D or solution F to room temperature, and use the electronic tongue to analyze solution D or solution F to establish a database; Step 7: Use the electronic tongue to analyze the tested water sample, use the database to establish a data analysis model and analyze the test results; Step 8: Solution D or F can also be used by sensory panelists to evaluate water quality samples. Solution D or F is stored in a 4°C refrigerator away from light. Each time a sensory analysis of a water sample is performed, Solution F and the tested water sample are kept at room temperature. The sensory panelists evaluate the taste of the tested water sample using Solution F as a reference. A water sample with a comprehensive score better than Solution F is deemed to have a better taste than Solution F. A water sample with a comprehensive score worse than Solution F is deemed to have a worse taste than Solution F. A water sample with a score consistent with Solution F is deemed to have a consistent taste with Solution F. The closer the score is to the taste of Solution F, the more similar the tested water sample and Solution F are.

7. The rapid detection method for evaluating the taste of drinking water using an electronic tongue according to claim 6, characterized in that: The container for dispensing solution D in step 5 is an ampoule bottle, and plastic or silicone rubber bottles shall not be used.

8. The rapid detection method for evaluating the taste of drinking water using an electronic tongue according to claim 6, characterized in that: The sterilization method described in step 5 is irradiation sterilization, pulse electric field sterilization, microwave sterilization, and static pressure sterilization.

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