Method for rapidly identifying fen-flavor pure grain solid-state white spirit
The method of using sodium hydroxide solution for colorimetric reaction and UV-Vis spectrophotometer to measure absorbance values solves the problem that ordinary consumers and small businesses have difficulty distinguishing between pure grain solid-state liquor and alcoholic beverages, achieving rapid, accurate, and low-cost identification results.
Patent Information
- Application Number
- CN202511884314.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-15
- Publication Date
- 2026-02-10
AI Technical Summary
Existing technologies make it difficult to quickly and accurately distinguish between pure grain solid-state liquor and alcoholic beverages among ordinary consumers and small businesses. Sensory identification is highly subjective, and instrumental identification methods are costly and complex to operate, making them difficult to popularize.
A method combining a sodium hydroxide solution colorimetric reaction with an ultraviolet-visible spectrophotometer to measure absorbance values is used to distinguish between pure grain solid-state liquor and alcohol-based liquor by observing the colorimetric reaction and measuring absorbance values. This method takes advantage of the characteristic that pure grain liquor exhibits a colorimetric reaction under alkaline conditions while alcohol-based liquor does not.
It provides a simple, fast, and low-cost identification method that can be operated by ordinary consumers, is highly accurate, and is suitable for use in homes and small sales locations, reducing identification costs and time.
Smart Images
Figure CN121499485A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of liquor identification technology, specifically, it relates to a method for identifying light-aroma pure grain solid-state liquor. Background Technology
[0002] In today's baijiu market, there is a rich variety of baijiu, which can be mainly divided into pure grain solid-state baijiu and alcohol-based baijiu. Pure grain solid-state baijiu is made using traditional techniques, with grains as raw materials, through solid-state fermentation, distillation, and aging. It has a mellow taste, rich aroma, and is rich in various beneficial flavor substances, making it very popular among consumers. Alcohol-based baijiu, on the other hand, is based on edible alcohol, with added flavorings and fragrances to simulate the taste and aroma of baijiu. It has a relatively lower cost and shorter production cycle, and also occupies a certain market share.
[0003] Currently, there are numerous methods for distinguishing between pure grain solid-state baijiu and alcohol-based baijiu, but all have certain limitations. Sensory identification is a common method, mainly involving observing the color and transparency of the liquid, smelling its aroma, and tasting it. For example, pure grain solid-state baijiu is usually clear and transparent, with a natural and mellow aroma, a rich and harmonious taste, and a long finish; while alcohol-based baijiu may have a more pungent and singular aroma, a thin taste, and a shorter finish. However, this method is too subjective; different people have different sensory sensitivities and judgment standards, making it difficult for inexperienced consumers to accurately distinguish between them, and they are easily misled.
[0004] Instrumental identification methods utilize specialized analytical instruments, such as gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) spectrometry, to precisely analyze the chemical components in baijiu (Chinese liquor) and thus determine its type. While this method is highly accurate, capable of detecting the content and proportion of various components in baijiu, it requires specialized equipment that is expensive, has high maintenance costs, and is complex to operate, requiring professional technicians for operation and data analysis. This makes instrumental identification methods difficult to popularize among ordinary consumers and small businesses, limiting their widespread use in practical identification.
[0005] Given the problems with existing identification methods, developing a simple, fast, accurate, low-cost, and intuitive method for distinguishing between pure grain solid-state liquor and alcoholic beverages is of great practical significance and market demand. This will not only help consumers make accurate choices when purchasing liquor and protect their rights, but also help regulate the liquor market order and promote the healthy development of the liquor industry. Summary of the Invention
[0006] To achieve the above objectives, this invention provides a rapid method for identifying light-aroma, pure grain solid-state liquor. This method offers high accuracy in distinguishing between pure grain liquor and alcohol-based liquor, effectively differentiating the two and providing consumers with a reliable basis for identification. It can be conveniently used for liquor identification in everyday home life or in small liquor stores, demonstrating strong practicality and high accuracy.
[0007] The technical solution provided by this invention is as follows: A method for rapidly identifying light-aroma pure grain solid-state liquor includes the following steps: (1) Observation of color reaction: Add different volume percentages of light-aroma pure grain solid liquor into glass test tubes, and then add an appropriate amount of sodium hydroxide solution with a concentration of 0.1-10 mol / L, and mix well; put the test tubes into hot water for a hot bath. After the hot bath, take out the test tubes, let them stand for 1-3 minutes, and observe whether the liquor in the test tubes shows color change.
[0008] The basis for identification is that during the brewing process of pure grain solid-state liquor, the starch and other substances in the grain undergo microbial fermentation, producing a variety of complex organic compounds, such as esters, alcohols, and acids. These components intertwine to form the unique flavor and quality characteristics of pure grain liquor. When heated under alkaline conditions, some organic compounds in pure grain liquor will react chemically with sodium hydroxide, resulting in a color reaction. In contrast, alcohol-based liquor is mainly based on edible alcohol, with added flavorings and fragrances. Its composition is relatively simple and lacks the specific organic compounds that can produce a color reaction under these conditions; therefore, it will not show a color change under the same experimental conditions.
[0009] (2) Absorbance measurement: The absorbance A of different pure grain solid volume ratios of baijiu was measured at 266 nm using a UV-Vis spectrophotometer after full-wavelength scanning of the colored liquor. 266 Using different pure grain solid volume ratios as the abscissa and absorbance values as the ordinate, a linear regression was performed on the absorbance values of baijiu and different pure grain solid volume ratios to obtain a linear regression equation. By measuring the absorbance values of baijiu with unknown pure grain solid volume ratios and substituting them into the linear regression equation, the pure grain solid volume ratio of light-aroma baijiu was calculated.
[0010] Preferably, in step (1), the volume of the liquor to be tested is 20 mL, the concentration of the sodium hydroxide solution is 10 mol / L, and the amount added is 4 mL.
[0011] Preferably, the temperature of the hot water in step (1) is 60-100℃, more preferably 80-100℃; the hot bath time is 1-5min, more preferably 3min.
[0012] Preferably, the linear regression equation in step (2) is y = 0.0508x + 0.2, where R02 =0.9991.
[0013] Compared with existing methods for identifying baijiu (Chinese liquor), the identification method of this invention has the following significant advantages: (1) The identification method is simple and convenient. You only need to prepare common glass test tubes, standard solutions and other materials, and follow the established steps to add solutions and perform hot bath operations. No professional wine tasting skills or complicated instrument operation knowledge are required. Ordinary consumers can easily master it.
[0014] (2) Low cost, wide availability of raw materials, no restrictions on operating environment, no need to invest a lot of money to purchase expensive instruments, reducing identification costs and making it suitable for large-scale promotion and application. Fast identification speed, the entire identification process only takes a few minutes, and the result can be obtained by observing color changes, which greatly improves identification efficiency and meets consumers' needs for quick judgment. Attached Figure Description
[0015] Figure 1 The effect of different amounts of sodium hydroxide added on the identification of pure grain liquor; Figure 2 The effect of hot bath time on the identification of pure grain liquor; Figure 3 The effect of different water bath temperatures on the identification of pure grain liquor; Figure 4 Solid-state colorimetric reaction diagrams of pure grains for light-aroma baijiu with different volume percentages; Figure 5 The absorbance value (A) of light-aroma baijiu 266 A linear regression diagram of the relationship between the percentage of solid grains and the percentage of whole grains; Figure 6 The color reaction diagram of the light-aroma baijiu is shown in the example. Detailed Implementation
[0016] To enable those skilled in the art to better understand the technical solutions disclosed in this invention, the technical solutions in the disclosed embodiments of this invention will be clearly and completely described below. Obviously, the described embodiments are merely a part of the embodiments disclosed in this invention, and not all of them. Based on the embodiments disclosed in this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.
[0017] This invention provides a method for identifying pure grain solid-state liquor. In multiple experimental verifications, a certain amount of sodium hydroxide solution is added to the liquor sample. After a specific temperature and water bath time, the organic matter in the liquor exhibits a color change (yellowish-brown) under alkaline heating conditions; the higher the content, the darker the color. Alcohol-based liquor, on the other hand, is mainly based on edible alcohol, with added flavorings and fragrances. Its composition is relatively simple and lacks specific organic matter that can undergo a color reaction under these conditions. To verify the accuracy of this method and improve the identification system, and to accurately quantify the proportion of pure grain solid-state liquor in the liquor, the inventors conducted spectral analysis on liquors with different pure grain solid-state proportions and compared the results with a standard curve. This invention has high accuracy in identifying pure grain liquor and alcohol-based liquor, effectively distinguishing between the two and providing consumers with a reliable basis for identification. It can be conveniently used for liquor identification in daily life at home or in small liquor stores, offering high practicality and accuracy.
[0018] The following is an examination of the important influencing factors in this identification method: (1) Determination of sodium hydroxide concentration Experiments were conducted using sodium hydroxide concentrations of 0.1 mol / L, 1 mol / L, and 10 mol / L. It was found that when the concentrations were 0.1 mol / L and 1 mol / L, 20 mL to 40 mL of sodium hydroxide solution was added for the wine to exhibit a noticeable color reaction. When the concentration was 10 mol / L, only 4 mL of sodium hydroxide solution was added to produce a noticeable color reaction. Considering practical operability, the final sodium hydroxide solution concentration was determined to be 10 mol / L.
[0019] (2) The effect of different amounts of sodium hydroxide added on the identification of pure grain liquor Add 20 mL of 100% 42-degree light-aroma pure grain solid-state liquor to five test tubes respectively, and then add 1 mL, 2 mL, 4 mL, 6 mL and 8 mL of 10 mol / L sodium hydroxide respectively. After heating in boiling water at 80-100℃ for 3 min, observe the color change of the solution. Observe and photograph the color reaction of different amounts of sodium hydroxide solution on the identification of pure grain liquor.
[0020] The colorimetric reactions of different amounts of sodium hydroxide solution on the identification of light-aroma pure grain liquor are as follows: Figure 1 As shown, the five test tubes, from left to right, correspond to samples with sodium hydroxide solution added in amounts of 1 mL, 2 mL, 4 mL, 6 mL, and 8 mL, respectively. As the added amount increases, the color reaction becomes significantly stronger. When the added amount is ≥4 mL, the solution color is uniformly yellowish-brown, indicating the color reaction has terminated. Therefore, based on the above, 4 mL of sodium hydroxide is the optimal amount.
[0021] (3) The effect of hot bath time on the identification of pure grain liquor Add 20 mL of 100% pure grain solid liquor to each of the five test tubes, followed by 4 mL of 10 mol / L sodium hydroxide solution. After heating in boiling water at 80-100℃ for 1 min, 2 min, 3 min, 4 min, and 5 min, observe the color change of the liquor. Observe and photograph the color reaction of different heating times for identifying pure grain liquor.
[0022] The effect of hot bath time on the colorimetric reaction for identifying pure grain liquor is as follows: Figure 2 As shown, the five test tubes, from left to right, correspond to samples with heating times of 1 min, 2 min, 3 min, 4 min, and 5 min, respectively. As the heating time increases, the colorimetric reaction becomes significantly stronger. After 3 min, the colorimetric reaction terminates, and the solution color remains consistent, consistently appearing yellowish-brown. Therefore, considering all factors, a heating time of 3 min is optimal.
[0023] (4) The effect of different water bath temperatures on the identification of pure grain liquor Add 20 mL of 100% pure grain solid liquor to each of the five test tubes, followed by 4 mL of 10 mol / L sodium hydroxide solution. After heating in boiling water at 60℃, 70℃, 80℃, 90℃, and 100℃ for 3 minutes, observe the color change of the liquor. Observe and photograph the color reaction of different water bath temperatures for identifying pure grain liquor.
[0024] The effect of different heat bath temperatures on the colorimetric reaction for identifying pure grain liquor, as follows: Figure 3 As shown, the five test tubes, from left to right, correspond to samples at water bath temperatures of 60℃, 70℃, 80℃, 90℃, and 100℃, respectively. The color reaction intensifies significantly with increasing bath time. When the water bath temperature reaches 80℃, the solution color shows no significant change, indicating the color reaction has terminated, and all samples exhibit a yellowish-brown hue. Therefore, based on the above, a bath temperature of 80-100℃ is acceptable.
[0025] (5) Observation of colorimetric reaction The above observations show that the color reaction of the liquor reaches its strongest when the amount of sodium hydroxide solution added is 4 mL, the water bath temperature is 80-100 min, and the water bath time is 3 min. Therefore, this method can quickly identify light-aroma pure grain solid-state liquor. The specific operating steps are as follows: Pour 20 mL of light-aroma pure grain solid-state liquor into a test tube, then add 4 mL of 10 mol / L sodium hydroxide standard solution and mix well; take out the prepared 80-100℃ boiling water and put the test tube into the boiling water for a hot bath for 3 min; after the hot bath, quickly remove the test tube from the hot water, let it stand for a while, and after the temperature of the solution in the test tube has cooled slightly, directly observe the color change of the liquor in the test tube.
[0026] (6) Absorbance value determination To verify the effectiveness of the method of the present invention, an ultraviolet spectrophotometer method was used for verification. Specifically, the absorbance A of different pure grain solid content baijiu of the light aroma type was measured at 266 nm using an ultraviolet-visible spectrophotometer. 266 Using different pure grain solid volume ratios as the abscissa and absorbance values as the ordinate, a linear regression was performed on the absorbance values of baijiu and different pure grain solid volume ratios to obtain the linear regression equation. By measuring the absorbance values of unknown light-aroma baijiu with different pure grain solid volume ratios and substituting them into the linear regression equation, the pure grain solid volume ratio of baijiu was calculated.
[0027] (7) Identification of pure grain solid-state liquor with different volume percentages Prepare six test tubes of the same size. Add 20 mL of each of the following concentrations to the test tubes: 0% pure grain solid-state liquor and 100% pure grain solid-state liquor; 20 mL of 20% light-aroma pure grain solid-state liquor (20% pure grain solid-state liquor and 80% pure grain solid-state liquor); 20 mL of 40% pure grain solid-state liquor (40% pure grain solid-state liquor and 60% pure grain solid-state liquor); 20 mL of 60% pure grain solid-state liquor (60% pure grain solid-state liquor and 40% pure grain solid-state liquor); 20 mL of 80% pure grain solid-state liquor (80% pure grain solid-state liquor and 20% pure grain solid-state liquor); and 20 mL of 100% pure grain solid-state liquor (100% pure grain solid-state liquor and 0% pure grain solid-state liquor). Place each test tube in a hot water bath at 80-100℃ for 3 minutes. After the bath, quickly remove the test tubes from the hot water and let them stand for a moment until the solution cools slightly. Observe the color changes of the liquor in each test tube. The results are as follows: Figure 4 As shown in the figure, the six test tubes, from left to right, represent samples with a pure grain solid-state liquor content of 0%, 20%, 40%, 60%, 80%, and 100%.
[0028] Depend on Figure 4 The results show that 100% pure grain solid-state baijiu exhibits a deep yellowish-brown color with a clear color reaction; 80% and 60% pure grain solid-state baijiu both exhibit a lighter yellowish-brown color with a significantly weaker color reaction; 40% pure grain solid-state baijiu is slightly yellow; 20% pure grain solid-state baijiu is almost colorless with a slight yellow tint; and 0% pure grain solid-state baijiu (alcohol-based baijiu) is colorless and does not exhibit a color reaction. In summary, alcohol-based baijiu shows no color reaction when heated under alkaline conditions, and the higher the proportion of pure grain solid-state baijiu, the stronger the color reaction. This indicates that the first step of the method of this invention, observing the color reaction, can roughly determine the range of the proportion of pure grain solid-state baijiu.
[0029] (8) Absorbance value determination The absorbance (A) of light-aroma baijiu with different pure grain solid content was measured at 266 nm using a UV-Vis spectrophotometer. 266Using different pure grain solid-state ratios as the x-axis and absorbance values as the y-axis, a linear regression was performed on the absorbance values of baijiu (Chinese liquor) and different pure grain solid-state ratios. The results are as follows: Figure 5 As shown.
[0030] Depend on Figure 5 It can be seen that there is a certain linear relationship between the proportion of pure grain solids in the baijiu sample and the absorbance value at 266nm. After linear regression, it was found that the linear relationship is good, and the R value of the regression line is [value missing]. 2 A value greater than 0.999 indicates that the pure grain solid content of light-aroma baijiu can be estimated by measuring the absorbance value of the baijiu sample at 266nm. This can not only verify the accuracy of the colorimetric reaction results, but also improve the identification system for the pure grain solid content of baijiu.
[0031] Example This embodiment takes a light-aroma baijiu with an unknown pure grain solid volume percentage as an example and uses the following method for rapid identification: (1) Pour 20 mL of the liquor sample to be tested into a test tube, then add 4 mL of 10 mol / L sodium hydroxide standard solution and mix well; take out the prepared 8-100℃ boiling water and put the test tube into the boiling water for a hot bath for 3 min; after the hot bath, quickly take the test tube out of the hot water, let it stand for 1 min, and directly observe the color change of the liquor in the test tube. The color reaction of light-aroma liquor with unknown pure grain solid volume percentage is as follows Figure 6 As shown. Comparison Figure 4 The intensity of the color reaction was used to determine that the pure grain solid content of the liquor sample was in the range of 80%-100%.
[0032] (2) The absorbance of the liquor sample at 266 nm was measured to be 4.77 using a UV-Vis spectrophotometer. The absorbance value was then substituted into... Figure 5 The regression equation shown calculates that the pure grain solid content of the liquor sample is 90%, proving the accuracy of the colorimetric reaction and also determining the pure grain solid content of the liquor sample.
[0033] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for rapidly identifying light-aroma pure grain solid-state liquor, characterized in that, Includes the following steps: (1) Observation of color reaction: Add different volume percentages of light-aroma pure grain solid-state liquor into glass test tubes, then add an appropriate amount of sodium hydroxide solution with a concentration of 0.1-10 mol / L, and mix well; put the test tubes into hot water for a heat bath, and after the heat bath, take out the test tubes, let them stand for 1-3 minutes, and observe whether the liquor in the test tubes shows color change; (2) Absorbance measurement: The absorbance A of different pure grain solid volume ratios of baijiu was measured at 266 nm using a UV-Vis spectrophotometer after full-wavelength scanning of the colored liquor. 266 Using different pure grain solid volume ratios as the abscissa and absorbance values as the ordinate, a linear regression was performed on the absorbance values of baijiu and different pure grain solid volume ratios to obtain a linear regression equation. By measuring the absorbance values of baijiu with unknown pure grain solid volume ratios and substituting them into the linear regression equation, the pure grain solid volume ratio of light-aroma baijiu was calculated.
2. The method according to claim 1, characterized in that, In step (1), the volume of the liquor to be tested is 20 mL, the concentration of the sodium hydroxide solution is 10 mol / L, and the amount added is 4 mL.
3. The method according to claim 1, characterized in that, The temperature of the hot water in step (1) is 60-100℃.
4. The method according to claim 3, characterized in that, The temperature of the hot water in step (1) is 80-100℃.
5. The method according to claim 1, characterized in that, The hot bath time in step (1) is 1-5 minutes.
6. The method according to claim 5, characterized in that, The preferred hot bath time in step (1) is 3 minutes.
7. The method according to claim 1, characterized in that, The linear regression equation in step (2) is y = 0.0508x + 0.2, where R0 2 =0.9991.