Method for degassing carbon dioxide-containing beverage and method for measuring total acid content

Abstract

The invention discloses a degassing method of a carbon dioxide-containing beverage and a determination method of total acid content, and relates to the technical field of detection and analysis. When the device for removing the carbon dioxide is used, the sealing cover is opened, the beverage to be degassed is placed in the oscillation cavity, the oscillation cavity is turned over through the driving assembly, the beverage to be degassed reciprocates under the action of gravity, and oscillation with the height being 30 cm or above is generated. The oscillation amplitude is increased, the lower the instantaneous pressure during oscillation is, the larger the free CO2 released by the beverage is, the larger the generated CO2 back pressure is, the pressure is relieved by arranging an exhaust port through the oscillation device, the free CO2 is continuously released in the continuous oscillation process, and therefore the free CO2 can be continuously released, and the exhaust purpose is achieved. In the exhaust process, volatile gas (such as acetic acid, propionic acid and the like) is retained in the beverage, so that the accuracy of total acid detection is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of detection and analysis, and more particularly to a method for degassing carbonated beverages and a method for determining the total acid content. Background Art

[0002] Beverages are added with CO2 (carbon dioxide) by maintaining a certain pressure, so that CO2 dissolves in the product to form bound carbonic acid. When the CO2 content in the beverage is ≥ 1.5 times its volume, it is usually called a carbonated beverage. The release of CO2 in the mouth of carbonated beverages plays a slight stimulating role, absorbs a certain amount of heat, and can bring a refreshing taste. Total acid is a very important indicator in foods, especially in products such as beverages, wines, and seasonings. The total acid directly determines the quality of the blended taste. Total acid refers to the expression of the total amount of measurable acidic substances in the product. Since there are many types of acids in foods and their composition and content also vary, it is generally calculated based on the acid with the highest content. Since carbonic acid is unstable and easily decomposes to form free CO2, which causes measurement deviation, the total acid in foods does not include this unstable and inaccurately measurable acid. Therefore, during the measurement process, it is necessary to first remove the CO2 in carbonated beverages, and this process is usually called degassing or CO2 removal.

[0003] The dissolution amount of CO2 in an aqueous solution maintains a certain parallelism with temperature, pressure, and solution pH. The lower the temperature, the higher the pressure, and the higher the pH, the easier it is to convert to bound CO2 (carbonic acid), and the greater the dissolution amount of CO2. There are generally three methods for degassing carbonated beverages or beverages containing CO2:

[0004] (1) Heating method

[0005] Utilizing the thermal instability of carbonic acid, by heating, it is decomposed into CO2 and water, and CO2 volatilizes during the heating process, and CO2 can be completely removed. For example, this principle is used in GB / T 12456-2008 "Determination of Total Acid in Foods". The disadvantage of this method is that there are differences in product heating equipment, heating power and time, and obvious laboratory differences, which are likely to cause the volatilization of non-volatile acids (such as acetic acid) in the beverage, and the total acid measurement result is likely to be low. Since the process requires heating to near boiling and cooling, the degassing time for single-sample measurement is also relatively long, and it is not suitable for the determination of beverages containing volatile acids, such as carbonated apple cider vinegar beverages and mature vinegar beverages containing CO2. Generally, it is used for the determination of the total acid of beverages without volatile acids, such as cola (mainly containing phosphoric acid).

[0006] (2) Oscillation exhaust method

[0007] Carbonated beverages are often acidic beverages. When they are impacted and oscillated under normal pressure, the instantaneous pressure decreases, and the carbonic acid in the beverage is converted into CO2 to form pressure. Exhausting reduces the pressure and the dissolved amount, reaching a new dissolution equilibrium state. Therefore, by repeatedly operating through oscillation and exhaust methods, the dissolved amount is reduced, thereby achieving the purpose of degassing. For example, in GB / T 4928-2008 "Beer Analysis Method", generally, the product is used in a conical flask, and through repeated oscillation and opening the plug for exhaust. Due to insufficient oscillation strength and difficulty in controlling the number of exhaust times, often part of the carbonic acid in the form of CO2 does not form free CO2, resulting in insufficient exhaust (removing CO2), and the total acid measurement result is prone to be too high and the reproducibility is difficult to control.

[0008] (3) Treatment with an ultrasonic oscillator

[0009] Using an ultrasonic oscillator to oscillate and degas the beverage, this method is extremely easy to remove free CO2. Due to the small amplitude of ultrasonic oscillation, it is often difficult to remove CO2 in the form of bound ionic state, resulting in a too high total acid measurement result and no reproducibility, and it is not suitable for total acid measurement.

[0010] Therefore, there is an urgent need to provide a method with good reproducibility to remove carbon dioxide from beverages, and at the same time solve problems such as insufficient exhaust (removing CO2) or inaccurate measurement caused by the volatilization of volatile acids.

[0011] In view of this, the present invention is specifically proposed. Summary of the Invention

[0012] The purpose of the present invention is to provide a degassing method for carbonated beverages and a method for measuring the total acid content, aiming to improve the accuracy of total acid content measurement and the reproducibility of the exhaust (removing CO2) process.

[0013] The present invention is implemented as follows:

[0014] In the first aspect, the present invention provides a degassing method for carbonated beverages, including: placing the beverage to be degassed in an oscillation cavity, and driving the oscillation cavity to flip to generate oscillation with a height of more than 30 cm.

[0015] Among them, the device for degassing includes: an oscillation cavity for accommodating the beverage to be degassed and a driving component for driving the oscillation cavity, so as to flip the oscillation cavity through the driving component, and the beverage to be degassed reciprocates under the action of gravity.

[0016] One end of the oscillation cavity is sealed, and the other end is detachably connected with a sealing cover. An exhaust channel is connected to the side wall of the oscillation cavity, and an exhaust port is arranged at the end of the exhaust channel to discharge carbon dioxide gas through the exhaust port on the exhaust channel.

[0017] In an alternative embodiment, by adjusting the height of the oscillation cavity, a height difference of 30 cm - 40 cm is generated during the flipping process of the beverage to be degassed;

[0018] Preferably, the ratio of the filling volume of the beverage to be degassed to the volume of the oscillation cavity is 1:(14 - 15);

[0019] Preferably, the number of flipping circles of the oscillation cavity is 35 - 45 circles.

[0020] In an alternative embodiment, the device for degassing further includes: a vertical support rod, and the driving assembly includes a rocker arm, a rocker arm connecting rod, and a cavity fixing clamp. The oscillation cavity is installed on the cavity fixing clamp, the rocker arm connecting rod is installed on the vertical support rod, one end of the rocker arm is connected to the rocker arm connecting rod, and the cavity fixing clamp is connected to the other end of the rocker arm connecting rod;

[0021] During the exhaust operation, rotate the rocker arm to drive the cavity fixing clamp to rotate through the rocker arm connecting rod, and then drive the oscillation cavity to flip.

[0022] In an alternative embodiment, the rocker arm connecting rod has damping to cause the oscillation cavity to pause in the vertical state;

[0023] Preferably, the rocker arm connecting rod is provided with a mounting hole, and a rotating connecting piece is arranged in the mounting hole; the rocker arm connecting rod includes a first connecting rod and a second connecting rod. One end of the first connecting rod is connected to the rocker arm, and the other end of the first connecting rod is connected to one end of the rotating connecting piece; one end of the second connecting rod is connected to the other end of the rotating connecting piece, and the other end of the second connecting rod is connected to the cavity fixing clamp; both the first connecting rod and the second connecting rod have damping.

[0024] In an alternative embodiment, the oscillation cavity includes a first cavity section, a second cavity section, and a third cavity section from top to bottom. The second cavity section is circular tubular, the inner diameters of the ends of the first cavity section and the third cavity section are both larger than the inner diameter of the second cavity section, and the pipe diameters of the first cavity section and the third cavity section gradually increase from the end close to the second cavity section to the end far from the second cavity section.

[0025] In an alternative embodiment, a convex buffer cavity is arranged in the middle of the oscillation cavity, and the exhaust channel is installed at the end of the buffer cavity to provide a buffer space for foam elimination through the buffer cavity.

[0026] In an alternative embodiment, an overflow collection cavity is arranged on the exhaust channel, a rotating communication plug is arranged on the exhaust channel between the buffer cavity and the overflow collection cavity, and the rotating communication plug is opened before the oscillation cavity flips.

[0027] In a second aspect, the present invention provides a method for determining the total acid content of a carbonated beverage, comprising: removing carbon dioxide by using the degassing method according to any one of the foregoing embodiments, and then testing the total acid content by using an alkali solution titration method.

[0028] In an optional embodiment, the process of testing the total acid content by using an alkali solution titration method includes: diluting the degassed sample with carbon dioxide-free water, titrating with a standard NaOH solution, observing the change in the pH value of the solution, and titrating until the pH value reaches the end point; simultaneously using carbon dioxide-free water to replace the sample for a blank test.

[0029] In an optional embodiment, the calculation formula for the total acid content of the sample is as follows:

[0030]

[0031] In the formula:

[0032] X represents the total acid of the sample, g / L or g / kg;

[0033] c represents the concentration of the standard NaOH solution used in the titration, mol / L;

[0034] V1 represents the amount of the standard NaOH solution consumed by the sample, mL;

[0035] V2 represents the amount of the standard NaOH solution consumed by the blank test, mL;

[0036] k represents the mass of acid equivalent to 1.00 mL of 1 mol / L standard NaOH solution, g / mmol;

[0037] F represents the sample dilution factor;

[0038] m represents the sample sampling amount, mL or g.

[0039] The present invention has the following beneficial effects: The present invention designs a device for removing carbon dioxide. When in use: open the sealing cover, place the beverage to be degassed in the oscillation cavity, and make the oscillation cavity flip through the driving component. The beverage to be degassed reciprocates under the action of gravity and undergoes oscillation with a height of more than 30 cm. By increasing the oscillation amplitude, the smaller the instantaneous pressure during oscillation, the greater the release of free CO2 from the beverage, and the greater the generated CO2 back pressure. The oscillation device is provided with an exhaust port for pressure relief to form a continuous oscillation process to continuously release free CO2. Therefore, free CO2 can be continuously released to achieve the purpose of exhausting gas. During the exhaust process, volatile gases (such as acetic acid, propionic acid, etc.) are retained in the beverage, improving the accuracy of the total acid detection.

[0040] In addition, the degassing method provided by the present invention can form a fixed operation method by verifying the number of oscillations and the amplitude (height) formed, complete the pretreatment operation before titration, and is beneficial to the reproducibility of the test method. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can be obtained based on these drawings.

[0042] Figure 1 It is a schematic structural diagram of the carbon dioxide removal device provided in this embodiment;

[0043] Figure 2 is Figure 1 a schematic structural diagram of the rocker connecting rod in

[0044] Reference numerals: 001 - rotation direction; 100 - carbon dioxide removal device; 110 - oscillation cavity; 111 - sealing cover; 112 - first cavity section; 113 - second cavity section; 114 - third cavity section; 115 - buffer cavity; 120 - drive assembly; 121 - rocker; 122 - rocker connecting rod; 1221 - first connecting rod; 1222 - second connecting rod; 123 - cavity fixing clamp; 1231 - top clamping member; 1232 - bottom clamping member; 1233 - connecting side arm; 130 - exhaust passage; 131 - exhaust port; 132 - overflow collection cavity; 133 - rotary communication plug; 141 - vertical support rod; 142 - base. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Those not specified in the embodiments are carried out according to conventional conditions or conditions recommended by the manufacturer. Those reagents or instruments not specified by the manufacturer can be obtained as conventional products through commercial purchase.

[0046] In order to accurately measure the total acid content in carbonated beverages, the present invention optimizes the pretreatment degassing process, solves problems such as insufficient exhaust (removing CO2) or inaccurate measurement caused by the volatilization of volatile acids, and can also reduce the operation time, improve efficiency, and maintain reproducibility.

[0047] In order to obtain the degassing method provided by the embodiments of the present invention, the inventors studied the degassing effects of different degassing methods, as shown in Table 1:

[0048] Table 1 Comparison of the effects of carbonated water base and degassing methods

[0049]

[0050] By comparing different degassing methods in Table 1, it can be seen that: for the oscillation height ≥ 30 cm and the boiling method, the degassing effect of carbonated water is the best, approaching the background value of pure water. However, the boiling method has problems such as long operation time consumption and easy loss of volatile acids; the ultrasonic oscillation degassing has a large deviation and a relatively high CO₂ residue, which will significantly affect the measurement results.

[0051] Based on the above verification conclusions, an embodiment of the present invention provides a degassing method for carbonated beverages, including: placing the beverage to be degassed in an oscillation cavity, and driving the oscillation cavity to flip, generating an oscillation with a height of more than 30 cm. By increasing the oscillation amplitude, the smaller the instantaneous pressure during oscillation, the greater the release of free CO₂ from the beverage, and the greater the generated CO₂ back pressure. An exhaust port is set through an oscillation device to relieve pressure, forming a continuous oscillation process to continuously release free CO₂, so that free CO₂ can be continuously released to achieve the purpose of exhausting gas. During the exhaust process, volatile gases (such as acetic acid, propionic acid, etc.) are retained in the beverage and will not affect the accuracy of the total acid detection.

[0052] During the actual operation process, Figure 1 and Figure 2 the provided carbon dioxide removal device 100 is used for degassing. The carbon dioxide removal device 100 includes: an oscillation cavity 110 and a driving component 120. Place the beverage to be degassed (such as a carbonated beverage) in the oscillation cavity 110, and drive the oscillation cavity 110 to flip through the driving component 120, so that the liquid in the oscillation cavity 110 reciprocates under the action of gravity (forming an oscillation form similar to free fall), with a very large oscillation amplitude, which is beneficial to quickly remove carbon dioxide.

[0053] One end of the oscillation cavity 110 is sealed (such as Figure 1 the bottom end in

[0054] In some embodiments, the oscillation cavity 110 includes a first cavity section 112, a second cavity section 113, and a third cavity section 114 from top to bottom. The second cavity section 113 is located in the middle position and is the main body of the oscillation cavity 110. The second cavity section 113 can be circular tubular. The inner diameters of the ends of the first cavity section 112 and the third cavity section 114 are both larger than the inner diameter of the second cavity section 113. That is to say, the diameters of both ends of the oscillation cavity 110 are larger, and the diameter of the middle main body part is smaller. The pipe diameter of the first cavity section 112 gradually increases from the end close to the second cavity section 113 to the end far from the second cavity section 113, that is, the cross-section of the first cavity section 112 is trapezoidal. Similarly, the pipe diameter of the third cavity section 114 gradually increases from the end close to the second cavity section 113 to the end far from the second cavity section 113, and the cross-section is also trapezoidal. The larger diameters at both ends of the oscillation cavity 110 are beneficial to providing space for the liquid to eject or overflow violently, and promoting the removal of carbon dioxide.

[0055] In some embodiments, a convex buffer cavity 115 is provided in the middle of the oscillation cavity 110, and the exhaust passage 130 is installed on the buffer cavity 115. The cross-section of the buffer cavity 115 is arc-shaped, and its three-dimensional shape can be a hemispherical or conical container. When a large amount of CO2 is released in the solution, the buffer cavity 115 can provide a buffer space for foam elimination, and can also provide a space for the solution to fall back during rotation to prevent it from being washed out of the column by CO2; at the same time, it is connected to a spherical container to form a CO2 discharge buffer, providing a larger decompression space and preventing the solution from ejecting or overflowing violently.

[0056] Furthermore, an overflow collection cavity 132 is provided on the exhaust passage 130. The overflow collection cavity 132 can temporarily collect the overflowing liquid to prevent it from overflowing from the exhaust port 131 of the exhaust passage 130. A rotary communication plug 133 is provided on the exhaust passage 130 between the buffer cavity 115 and the overflow collection cavity 132. The rotary communication plug 133 can be a common valve, serving as a control valve for communicating with the outside world, and the valve is opened in the communication state when rotating.

[0057] In some embodiments, the carbon dioxide removal device 100 further includes a vertical support rod 141 and a base 142. The bottom of the vertical support rod 141 is fixedly connected to the base 142, and the driving assembly 120 is installed on the vertical support rod 141. The vertical support rod 141 and the base 142 can be fixed by welding or other means to enable the device to operate stably during rotation.

[0058] Further, the driving assembly 120 includes a rocker arm 121, a rocker arm connecting rod 122, and a cavity fixing clip 123. The oscillating cavity 110 is installed on the cavity fixing clip 123. The rocker arm connecting rod 122 is installed on the vertical support rod 141. One end of the rocker arm 121 is connected to the rocker arm connecting rod 122, and the other end of the cavity fixing clip 123 is connected to the rocker arm connecting rod 122. During the exhaust operation, the operator manually rotates the rocker arm 121 to drive the rocker arm connecting rod 122 and the cavity fixing clip 123 to rotate, thereby driving the oscillating cavity 110 to rotate.

[0059] In some embodiments, an installation hole (not shown in the figure) is provided on the rocker arm connecting rod 122, and a rotating connecting member (not shown in the figure) is provided in the installation hole. The size of the rotating connecting member is matched with the installation hole and can rotate in the installation hole. Specifically, the installation hole can be a round hole penetrating the vertical support rod 141, and the rotating connecting member can be a cylinder matched with the round hole and passes through the installation hole. As Figure 2 shown, the rocker arm connecting rod 122 includes a first connecting rod 1221 and a second connecting rod 1222. One end of the first connecting rod 1221 is connected to the rocker arm 121, and the other end of the first connecting rod 1221 is connected to one end of the rotating connecting member; one end of the second connecting rod 1222 is connected to the other end of the rotating connecting member, and the other end of the second connecting rod 1222 is connected to the cavity fixing clip 123. Specifically, threads can be provided at the end of the rotating connecting member, and the first connecting rod 1221 and the second connecting rod 1222 can be connected to the rotating connecting member by means of threaded connection and rotate around the rotation direction 001 during the process.

[0060] To improve the oscillation effect, both the first connecting rod 1221 and the second connecting rod 1222 have damping (i.e., the rocker arm connecting rod 122 has damping). When the cylinder is in a vertical state, there is a short pause, increasing the vertical state time, causing the beverage still on the middle wall surface of the cylinder to fall back and be collected, increasing the free fall height for the next time. The way to form damping is not limited, and existing damping formation methods can be adopted.

[0061] In some embodiments, the cavity fixing clip 123 includes a top clamping member 1231, a bottom clamping member 1232, and a connecting side arm 1233 for connecting the top clamping member 1231 and the bottom clamping member 1232. The rocker arm connecting rod 122 is connected to the connecting side arm 1233. By clamping the oscillating cavity 110 with the top clamping member 1231 and the bottom clamping member 1232, the clamping stability can be improved. The top clamping member 1231, the bottom clamping member 1232, and the connecting side arm 1233 can be fixed by welding, or the top clamping member 1231 and the bottom clamping member 1232 can also be detachably connected.

[0062] Further, both the top clamping member 1231 and the bottom clamping member 1232 are provided with clamping notches (not shown in the figure) that match the outer shape of the oscillation cavity 110. Structures such as fixing rings made of rubber material can be provided at the clamping notches, which can improve the clamping stability.

[0063] In a preferred embodiment, by adjusting the height of the oscillation cavity 110, a height difference of 30 cm - 40 cm is generated during the flipping process of the beverage to be degassed. The ratio of the filling volume of the beverage to be degassed to the volume of the oscillation cavity is 1:(14 - 15), such as 1:14.0, 1:14.5, 1:15.0, etc. The number of flipping circles of the oscillation cavity is 35 - 45 circles, such as 35 circles, 38 circles, 40 circles, 43 circles, 45 circles, etc. Compared with the oscillation amplitude of less than 20 cm of the conical flask, the degassing effect of carbon dioxide can be significantly improved.

[0064] It should be noted that the degassing method provided by the embodiments of the present invention has the following advantages: it can effectively remove CO2 from the beverage and retain volatile acids, and through verification, the effective degassing operation steps of the device are set to achieve detection reproducibility and accuracy; it shortens the sample processing time, improves the sample processing efficiency and measurement accuracy; for the sample after degassing, an appropriate sample is taken and the total acid content of the carbonated vinegar beverage is determined by the method of acid-base titration.

[0065] The embodiments of the present invention also provide a method for determining the total acid content of a carbonated beverage, including: removing carbon dioxide by using the degassing method provided by the embodiments of the present invention, and then testing the total acid content by the method of titration with an alkali solution. Compared with the national standard method, the pretreatment operation is clearer, the result is closer to the true value, and the measurement accuracy can be improved.

[0066] The specific titration method can adopt the national standard method, such as GB 12456 - 2021 "National Food Safety Standard - Determination of Total Acids in Foods", but it is not limited thereto.

[0067] In some embodiments, the process of testing the total acid content by the method of titration with an alkali solution includes: diluting the degassed sample with carbon dioxide-free water, such as filtering the sample if it is turbid and then taking the sample, titrating with a NaOH standard solution, observing the change in the pH value of the solution, and titrating to the end point (the end point pH value is 8.7 - 8.8 calculated based on phosphoric acid, and 8.2 calculated based on other acids); at the same time, a blank test is carried out by substituting carbon dioxide-free water for the sample. Titrating with a NaOH standard solution and carrying out a blank test are simple and easy to operate, and the detection accuracy is relatively high.

[0068] Further, the calculation formula for the total acid content of the sample is as follows:

[0069]

[0070] In the formula:

[0071] X represents the total acid of the sample, g / L or g / kg;

[0072] c represents the concentration of the NaOH standard solution used in the titration, mol / L;

[0073] V1 represents the volume of the NaOH standard solution consumed by the test sample, mL;

[0074] V2 represents the volume of the NaOH standard solution consumed by the blank test, mL;

[0075] k represents the mass of acid equivalent to 1.00 mL of 1 mol / L NaOH standard solution, g / mmol; for example: malic acid, 0.067; acetic acid, 0.060; tartaric acid, 0.075; citric acid, 0.064; citric acid (containing one molecule of crystal water), 0.070; lactic acid, 0.090; hydrochloric acid, 0.036; sulfuric acid, 0.049; phosphoric acid, 0.049; generally, vinegar beverages are calculated based on acetic acid;

[0076] F represents the dilution factor of the sample, 1 if not diluted;

[0077] m represents the sampling amount of the sample, mL or g.

[0078] Measurement control requirements: The same sample is measured twice, and the result is the average value. The calculation result is retained to 2 decimal places; the absolute difference between the two independent measurement results under repeatability conditions shall not exceed 2% of the arithmetic mean.

[0079] The features and performance of the present invention will be further described in detail below in conjunction with the embodiments.

[0080] Embodiment 1

[0081] This embodiment provides a method for determining the total acid content of a carbonated beverage, and the steps are as follows:

[0082] (1) Degassing

[0083] Using Figure 1 The carbon dioxide removal device 100 in it for degassing. The device dimensions are as follows: The inner diameter of the end of the first cavity section 112 is 120 mm, and the height is 50 mm; the height of the second cavity section 113 is 400 - 450 mm, and the inner diameter is 80 mm; the height of the third cavity section 114 is 50 mm, and the inner diameter of the end is 120 mm.

[0084] The ratio of the liquid filling volume to the total volume of the oscillation cavity 110 is 1:(14 - 15).

[0085] Take about 200 mL of the gas-containing sample, place it in the above degassing device, open the exhaust valve, rotate it 30 - 50 turns, then remove the CO2 gas, and control the number of turns rotated every 30 s to be 6 turns.

[0086] (2) Titration

[0087] Take 25 mL of the sample after degassing treatment by volume sampling or 25 g by weight sampling, accurate to 0.01 g (the sampling amount is m) (if the sample is turbid, filter it with a fast filter paper, discard the initial filtrate, collect the subsequent filtrate, and then sample; if the acidity of the sample is too high, first dilute it with CO2-free water, the dilution factor is F, and then sample), place it in a 200 mL beaker, and add 75 mL of CO2-free water. Place the beaker on a magnetic stirrer, immerse the pH meter electrode into the solution, titrate with a 0.1 mol / L sodium hydroxide standard solution (the actual concentration is c), observe the numerical change of the pH of the solution at any time, when approaching the titration end point, slow down the titration speed, add half a drop (at most one drop) at a time until the titration end point, and the consumed volume is V1. At the same time, use CO2-free water to replace the sample for a blank test, and the consumed volume is V0. Calculate according to formula (1).

[0088] Measurement control requirements: The same sample is determined twice, and the result is taken as the average value, and the calculation result is reserved to 2 decimal places; the absolute difference between the two independent determination results under repeatability conditions shall not exceed 2% of the arithmetic average value.

[0089] Calculate the total acid content according to formula (1).

[0090] Comparative Example 1

[0091] The difference from Example 1 is only that: in step (1), the sample is treated by shaking under reduced pressure in a conical flask (continuously shaking while maintaining negative pressure after suction filtration with a suction pump) for 3 min - 4 min, and no obvious bubbles are released from the sample.

[0092] Test Example 1

[0093] Test the accuracy and reproducibility of the detection methods provided by the examples and comparative examples, and the results are shown in Table 2.

[0094] At the same time, use acetic acid solutions of the same concentration to dilute and prepare a gas-containing acetic acid solution (0.5% acetic acid solution, CO2 volume is about 3 times) and a non-gas-containing acetic acid solution (0.5% acetic acid solution), and both are sealed in aluminum can packages. The former is used as a simulated gas-containing volatile acid beverage product, and the latter is used as a non-gas-containing volatile acid beverage and used as a comparison benchmark to select a degassing method close to the actual situation.

[0095] Table 2 Comparison of the effects of different degassing methods in examples and comparative examples

[0096]

[0097] It can be seen that the result of the degassing device is closest to the true result after rotating 40 circles, and the result deviation does not exceed the requirement of 2%.

[0098] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for degassing a carbonated beverage, characterized in that: include: Placing the beverage to be degassed in the oscillation cavity, and driving the oscillation cavity to flip, so as to cause oscillation at a height of more than 30 cm; The degassing device comprises: an oscillating cavity for accommodating the beverage to be degassed and a driving assembly for driving the oscillating cavity, so that the oscillating cavity is turned over by the driving assembly, and the beverage to be degassed reciprocates under the action of gravity; One end of the oscillation cavity is sealed, and the other end is detachably connected to a sealing cover. The side wall of the oscillation cavity is connected to an exhaust channel, and an exhaust port is provided at the end of the exhaust channel to discharge carbon dioxide gas through the exhaust port on the exhaust channel.

2. The method for degassing a carbonated beverage according to claim 1, characterized in that: By adjusting the height of the oscillation cavity, the deaerated beverage generates a height difference of 30 cm to 40 cm during the turning process; Preferably, the ratio of the volume of the beverage to be degassed to the volume of the oscillation chamber is 1:(14-15); Preferably, the oscillation cavity flips 35 to 45 times.

3. The method for degassing a carbonated beverage according to claim 1 or 2, characterized in that: The degassing device further comprises: a vertical support rod, the driving assembly comprises a rocker arm, a rocker arm connecting rod and a cavity fixing clamp, the oscillation cavity is mounted on the cavity fixing clamp, the rocker arm connecting rod is mounted on the vertical support rod, the rocker arm is connected to one end of the rocker arm connecting rod, and the cavity fixing clamp is connected to the other end of the rocker arm connecting rod; During the exhaust operation, the rocker arm is rotated to drive the cavity fixing clamp to rotate through the rocker arm connecting rod, thereby driving the oscillation cavity to flip.

4. The method for degassing a carbonated beverage according to claim 3, characterized in that: The rocker arm connecting rod has damping to make the oscillation cavity pause when in a vertical state; Preferably, a mounting hole is provided on the rocker arm connecting rod, and a rotating connecting piece is provided in the mounting hole; the rocker arm connecting rod comprises a first connecting rod and a second connecting rod, one end of the first connecting rod is connected to the rocker arm, and the other end of the first connecting rod is connected to one end of the rotating connecting piece; one end of the second connecting rod is connected to the other end of the rotating connecting piece, and the other end of the second connecting rod is connected to the cavity fixing clamp; the first connecting rod and the second connecting rod are both provided with damping.

5. The method for degassing a carbonated beverage according to claim 1, characterized in that: The oscillation cavity includes a first cavity segment, a second cavity segment and a third cavity segment from top to bottom, the second cavity segment is a circular tube, the inner diameters of the ends of the first cavity segment and the third cavity segment are larger than the inner diameter of the second cavity segment, and the diameters of the first cavity segment and the third cavity segment gradually increase from one end close to the second cavity segment to the end far away from the second cavity segment.

6. The method for degassing a carbonated beverage according to claim 1, characterized in that: A convex buffer cavity is arranged in the middle of the oscillation cavity, and the exhaust passage is installed at the end of the buffer cavity to provide a buffer space for eliminating bubbles through the buffer cavity.

7. The method for degassing a carbonated beverage according to claim 6, characterized in that: An overflow collecting chamber is arranged on the exhaust passage, and a rotating connecting plug is arranged on the exhaust passage between the buffer chamber and the overflow collecting chamber. The rotating connecting plug is opened before the oscillation chamber is turned over.

8. A method for determining the total acid content of a carbonated beverage, characterized in that: include: The carbon dioxide is removed by the degassing method described in any one of claims 1 to 7, and then the total acid content is tested by an alkaline solution titration method.

9. The method for determining the total acid content of a carbonated beverage according to claim 8, characterized in that: The process of testing the total acid content by alkaline solution titration includes: diluting the degassed sample with carbon dioxide-free water, titrating with NaOH standard solution, observing the change in the pH value of the solution, and titrating to the endpoint; and performing a blank test by replacing the sample with carbon dioxide-free water.

10. The method for determining the total acid content of a carbonated beverage according to claim 9, characterized in that: The total acid content of the sample is calculated as follows: Where: X represents the total acid of the sample, g / L or g / kg; c represents the concentration of the NaOH standard solution used for titration, mol / L; V1 represents the amount of NaOH standard solution consumed by the sample, mL; V2 represents the amount of NaOH standard solution consumed in the blank test, mL; k represents the mass of 1.00mL, 1mol / L NaOH standard solution equivalent to the acid, g / mmol; F represents the sample dilution factor; m represents the sample volume, mL or g.

Images