Method for representing alcohol degree and category through pressure threshold

Abstract

The invention discloses a method for representing alcohol degree and category through a pressure threshold. According to the method, the wine liquid is combined with a porous membrane by utilizing the surface tension characteristic of the wine liquid and the difference of the inhibition degree of the oxidation-reduction reaction of metal ions, and the pressure threshold change when gas passes through the porous membrane is measured, so that the rapid characterization of the alcohol degree and the type of the wine is realized. The method has the advantages of simplicity and convenience in operation, simplicity in data processing, high detection efficiency and the like, and can be widely applied to rapid distinguishing of alcohol degrees and categories in various detection scenes.

Description

Technical Field

[0001] The present invention relates to the technical field of wine identification, and in particular to a method for characterizing the alcohol content and type of wine by using a pressure threshold. Background Art

[0002] Food is one of the basic needs of human beings in daily life. Science and technology play an important role in the production, processing, transportation and final product inspection of food. Especially in the field of food testing, the simplicity and efficiency of testing technology are particularly critical. Food testing is not only the basis for ensuring food quality, but also has become an indispensable part of the food industry.

[0003] As one of the common foods, the types and market size of alcoholic beverages are constantly expanding, from traditional beer and liquor to current craft beer, fruit wine, etc. At the same time, consumers are paying more and more attention to the alcohol content and category of alcohol. As one of the key parameters for evaluating the quality of alcoholic foods, alcohol content not only directly affects market positioning, but also largely determines consumers' purchasing decisions and drinking experience. In the actual consumption process, in addition to paying attention to alcohol content, consumers usually choose according to the category of alcohol, and tend to use brand as an important reference. For example, well-known brands such as Moutai, Wuliangye, and Fenjiu in liquor have their own unique aroma and taste that meet the needs of different consumer groups. Therefore, for alcoholic beverage manufacturers, it is of great significance to conduct scientific evaluation of alcohol content and category.

[0004] At present, the evaluation methods of wine are mainly divided into two categories: sensory evaluation and instrumental analysis. Sensory evaluation usually uses the senses of smell, taste and vision of professional wine tasters to judge the quality of wine, but this method is significantly subjective, and the evaluation results between different wine tasters may vary greatly. At the same time, sensory evaluation is difficult to quantify, and the consistency and reliability of the evaluation results cannot be guaranteed. In contrast, instrumental analysis methods have higher objectivity and accuracy. Currently, commonly used instrumental analysis methods include spectroscopy, chromatography-mass spectrometry, colorimetric sensor array method, etc., but these methods still have the following shortcomings: On the one hand, these methods are usually complicated to operate and need to be operated by professional technicians. On the other hand, these methods often generate a large amount of data during the detection process, which needs to be analyzed after dimensionality reduction processing, which places high demands on the data processing capabilities of the testers. These problems make it difficult for existing instrumental analysis methods to meet the growing demand for rapid detection in the wine industry. Summary of the invention

[0005] To achieve the above object, the technical solution of the present invention is:

[0006] A method for characterizing the alcohol content of wine by using a pressure threshold comprises the following steps: selecting wine of unknown alcohol content to infiltrate a porous membrane to form an identification unit; using a gas delivery device to deliver gas to the identification unit in a sealing device at a certain flow rate; the ethanol content in the wine will change the pressure threshold of the gas passing through the identification unit; obtaining a pressure threshold signal through a digital display unit, and calculating the alcohol content of the wine based on the pressure threshold.

[0007] Optionally, the porous membrane material includes but is not limited to one of an organic nylon membrane, a hydrophilic polytetrafluoroethylene membrane, a hydrophilic polyvinylidene fluoride membrane, a polyethersulfone membrane, and the like.

[0008] Optionally, the gas includes but is not limited to one of air, oxygen, nitrogen, argon, and carbon dioxide.

[0009] Optionally, the pore size of the porous membrane includes but is not limited to one of 0.1 to 20 μm.

[0010] Optionally, the sealing device includes but is not limited to a filter membrane support, an acrylic plate, or a stainless steel clamp.

[0011] Another object of the present invention is to provide a method for characterizing wine categories by using a pressure threshold, comprising the following steps: allowing the wine to be tested to interact with a functional liquid on a porous membrane; since different types of wine have different degrees of inhibition on the metal ion reduction reaction, the metal ions are deposited on the porous membrane to different degrees, which in turn affects the surface energy of the porous membrane and ultimately changes the pressure threshold of the identification unit; and obtaining the pressure threshold difference before and after the reaction through a digital display unit to identify the type of wine.

[0012] Optionally, the functional liquid contains metal ions, a reducing agent and a surfactant. Further, in the functional liquid, the concentration ratio of the metal ions to the reducing agent is (1:1) to (4:1), and the concentration of the surfactant is 4 mM to 20 mM.

[0013] Optionally, the metal ions include but are not limited to one of gold ions, silver ions, copper ions, platinum ions, etc. The concentration range may be 4mM-400mM.

[0014] Optionally, the reducing agent includes but is not limited to one of vitamin C, o-phenylenediamine, p-phenylenediamine, p-dihydroxybenzene, p-aminophenol, hydrazine hydrate, sodium citrate, sodium borohydride and the like.

[0015] Optionally, the surfactant includes but is not limited to one of sodium dodecylbenzene sulfonate, hexadecyltrimethylammonium bromide, sodium dodecyl sulfate, dodecylbenzyldimethylammonium chloride, sodium stearate, and the like.

[0016] Beneficial effects of the present invention:

[0017] The present invention uses pressure threshold to characterize the alcohol content and category. This method has the advantages of simple operation, simple data processing, and high detection efficiency. It can be widely used for rapid differentiation of alcohol content and category in various detection scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the system structure of the embodiment.

[0019] Figure 2 This is a schematic diagram of the alcohol content differentiation principle of Example 1.

[0020] Figure 3 The UV spectra of vitamin C after silver reduction by adding different wines.

[0021] Figure 4 This is a comparison chart of the predicted values ​​and actual values ​​of different alcohol content in Example 1.

[0022] Figure 5 This is a relationship diagram between different concentrations of ethanol solutions and pressure thresholds in Example 1.

[0023] Figure 6 This is a graph showing the corresponding pressure drop ratios for different wines in Example 2. DETAILED DESCRIPTION

[0024] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments.

[0025] Figure 1 This is the device used in the invention, in which: 1 is a gas transport device, 2 is a transport channel, 3 is an identification unit, 4 is a sealing device, and 5 is a digital display unit. The gas transport device 1 is used to transport gas to the identification unit 3; the transport channel 2 is used to connect the devices to ensure air tightness; the identification unit 3 is composed of a gated liquid, a functional liquid and a porous membrane, and has a stimulus-responsive valve switch function for the wine to be tested; the functional liquid can react with the wine to be tested, thereby controlling the pressure of the gas passing through the identification unit; the sealing device 4 is used to encapsulate the identification unit 3; the digital display unit 5 includes a pressure sensor and a signal display, which can convert the alcohol content and category into a signal that can be directly read.

[0026] The principle of the present invention for identifying alcohol content is as follows Figure 2 As shown, the ethanol content in the wine determines the alcohol content of the wine. Wines of different alcohol content correspond to different surface tensions. The lower the surface tension of the gated liquid 32, the lower the pressure threshold measured by the digital display unit 5. The alcohol content of the wine can be obtained based on the change in the pressure threshold.

[0027] The principle of the present invention for identifying wine categories is based on the different effects of different wines on the reduction of metal ions. Taking silver ions as an example, Figure 3As shown in the figure, by measuring the absorbance of the characteristic peak (246nm) of the ultraviolet spectrum of the reducing agent vitamin C, it can be seen that different wines cause different amounts of vitamin C remaining after reduction, indicating that different wines have different degrees of inhibition on the metal reduction process. Using this principle, it is deposited on the membrane, which in turn affects the surface energy of the porous membrane, resulting in a specific change in the pressure threshold difference, thereby distinguishing different types of wine.

[0028] Example 1 - Detecting alcohol content

[0029] by Figure 1 Based on the structure shown in the figure, the wine to be tested is selected as the gate liquid, and the identification unit is formed by infiltrating the organic nylon membrane with a pore size of 1μm. The gas delivery device delivers air at a flow rate of 2mL / min. The obtained pressure threshold is substituted into the pre-established equation of ethanol concentration and pressure threshold to obtain the degree of the wine. The test results are shown in Figure 4 shown.

[0030] The equation of ethanol concentration and pressure threshold is that ethanol of different known degrees (e.g. 0-100% vol) is used as the gating liquid in advance to infiltrate the hydrophilic organic nylon membrane with a pore size of 1 μm to form an identification unit. The pressure threshold corresponding to different alcohol degrees is obtained through the digital display unit, and the equation of ethanol and pressure threshold is established. The measured pressure threshold is used as the ordinate and the volume fraction of the ethanol series standard solution is used as the abscissa to draw a curve, and the equation is obtained after fitting the curve: y is the pressure threshold, x is the ethanol concentration, and e is the exponential function. Fitting index r 2 =0.990, such as Figure 5 shown.

[0031] Example 2 - Identifying Wine Brands

[0032] Deionized water was selected as the gating liquid, and the identification unit was formed by infiltrating a hydrophilic polytetrafluoroethylene membrane with a pore size of 1 μm. The gas delivery device delivered air at a flow rate of 2 mL / min to test its initial pressure threshold P0. After 1 mL of the unknown wine sample was mixed with 1 mL of 200 mM vitamin C reducing agent for 20 minutes, 20 μL of 400 mM silver nitrate solution, 20 mM sodium dodecylbenzene sulfonate surfactant, and the reducing agent vitamin C mixed with the wine were added to the above membrane in sequence, and the reaction was carried out for 20 minutes. After the reaction, silver particles will be generated on the membrane, and then the porous membrane will be repeatedly washed with deionized water for 2 to 3 times and blown dry. Deionized water was selected as the gating liquid again, and the above membrane was infiltrated and the pressure threshold P was tested. The pressure drop ratio before and after the reaction (P0-P) / P0 was calculated, and the category of the wine was determined by comparing it with the pre-established database.

[0033] The above database is obtained by adding different wines to the membrane to react with the functional liquid, using deionized water as the gating liquid, and testing the pressure thresholds before and after the reaction according to the above operation, such as Figure 6 shown.

[0034] The above embodiments are only used to further illustrate a method of using a pressure threshold to characterize the alcohol content and category of the present invention, but the present invention is not limited to the embodiments. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for characterizing alcohol content by using a pressure threshold, comprising the following steps: A porous membrane is soaked with wine of unknown alcohol content to form an identification unit; a gas delivery device is used to deliver gas to the identification unit in a sealed device; different ethanol contents in the wine change the pressure threshold of the gas passing through the identification unit; a pressure threshold signal is obtained through a digital display unit, and the alcohol content of the wine is calculated based on the pressure threshold.

2. The method of characterizing alcohol content by using pressure threshold according to claim 1, characterized in that: The porous membrane material includes at least one of an organic nylon membrane, a hydrophilic polytetrafluoroethylene membrane, a hydrophilic polyvinylidene fluoride membrane, and a polyethersulfone membrane; the sealing device includes at least one of a filter membrane support, an acrylic plate, and a stainless steel clamp.

3. The method of characterizing alcohol content by using pressure threshold according to claim 1, characterized in that: The gas includes at least one of air, oxygen, nitrogen, argon and carbon dioxide.

4. The method of characterizing alcohol content by using pressure threshold according to claim 1, characterized in that: The pore size of the porous membrane is 0.1-20 μm.

5. The method of characterizing alcohol content by using pressure threshold according to claim 1, characterized in that: The method for calculating the alcohol content of wine based on the pressure threshold is as follows: take the measured pressure threshold as the ordinate and the volume fraction of the ethanol series standard solution as the abscissa, draw a curve, and get the equation after fitting the curve: Where y is the pressure threshold and x is the ethanol concentration.

6. A method for characterizing wine categories by using a pressure threshold, comprising the following steps: The wine to be tested is allowed to interact with the functional liquid on a porous membrane. Different types of wine have different degrees of inhibition on the metal ion reduction reaction, resulting in different degrees of metal ion deposition on the porous membrane, which in turn affects the surface energy of the porous membrane and ultimately changes the pressure threshold of the identification unit. The pressure threshold difference before and after the reaction is obtained through a digital display unit to identify the type of wine.

7. The method for characterizing wine categories by using pressure threshold according to claim 6, characterized in that: The functional liquid contains metal ions, a reducing agent and a surfactant.

8. The method for characterizing wine categories by using pressure threshold according to claim 7, characterized in that: The metal ions include at least one of gold ions, silver ions, copper ions and platinum ions.

9. The method for characterizing wine categories by using pressure threshold according to claim 7, characterized in that: The reducing agent includes at least one of vitamin C, o-phenylenediamine, p-phenylenediamine, p-dihydroxybenzene, p-aminophenol, hydrazine hydrate, sodium citrate and sodium borohydride.

10. The method for characterizing wine categories by using pressure threshold according to claim 7, characterized in that: The surfactant includes at least one of sodium dodecylbenzene sulfonate, hexadecyltrimethylammonium bromide, sodium dodecyl sulfate, dodecylbenzyldimethylammonium chloride, and sodium stearate.

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