Preparation method of low-sugar high-acidity potato vinegar

Abstract

The invention relates to the technical field of fermentation devices, in particular to a preparation method of low-sugar high-acidity potato vinegar. Wherein the aerobic fermentation device comprises a fermentation kettle, the fermentation kettle is used for carrying out aerobic fermentation on the fermented soybean milk liquid subjected to anaerobic fermentation, namely, alcohol in the soybean milk is converted into acetic acid through acetic acid bacteria, and an oxygen dissolving pump for conveying oxygen to the fermentation liquid is arranged in the center of the bottom of the fermentation kettle; a stirring fermentation liquid is arranged at the inner axis of the fermentation kettle; when insoluble impurities reach the edge of the interception plate, the insoluble impurities are driven by vortex generated by rotation of the stirring paddle to rotate along the edge of the interception plate, when the impurities reach the position close to the suction nozzle, suction force generated by the draw-off pump drives the impurities and fermentation liquor to penetrate through the transfer pipe together to enter the pipe body, and the fermentation liquor penetrates through the liquid drainage hole to be recycled into the fermentation liquor main body. And the impurities are blocked by the one-way valve and cannot return to the fermentation liquid main body, so that the impurities penetrate through the slag discharge pipe and are pumped out of the fermentation kettle by the draw-off pump.

Description

Technical Field

[0001] The invention relates to the technical field of fermentation devices, in particular to a method for preparing low-sugar and high-acid potato vinegar. Background Art

[0002] The potato vinegar production process involves several key steps: enzymatic hydrolysis, which converts potato starch into glucose; alcoholic fermentation, which converts glucose into alcohol; and acetic fermentation, which converts alcohol into acetic acid. During the acetic fermentation stage, 24 hours after inoculating the fermentation broth with acetic acid bacteria, the acidity level must be monitored and monitored immediately. This stage not only determines the high-acid flavor of the potato vinegar but also determines whether the final vinegar exceeds the alcohol content standard, thereby determining whether the finished product meets the alcohol content standard for non-alcoholic beverages.

[0003] Existing potato vinegar fermentation tanks typically use a pH meter to monitor the pH of the fermentation broth. If the acidity of the fermentation broth fails to increase, the main reasons are: 1. Excessive alcohol content inhibits the activity of acetic acid bacteria; 2. Insufficient acetic acid bacteria inoculum. If the alcohol content is high, the fermentation broth needs to be diluted, while if the inoculum is insufficient, additional inoculum needs to be added.

[0004] However, existing pH meters cannot pinpoint the specific reason why the fermentation broth's acidity hasn't increased. If the lack of acidity is due to high alcohol content, then even if more bacteria are added to the broth, the activity of the acetic acid bacteria will be inhibited by the alcohol. If the lack of acidity is due to insufficient bacteria, then diluting the broth won't increase the acidity. Furthermore, in the later stages of acetic acid fermentation, as the broth's pH decreases, bacterial proteins denature and combine with metal ions to produce insoluble impurities. These impurities are hydrophobically adsorbed to the acetic acid bacteria cell surface, disrupting the integrity of the phospholipid bilayer and reducing the number of viable cells.

[0005] In view of this, we propose a preparation method of low-sugar and high-acid potato vinegar to improve the deficiencies in the prior art. Summary of the Invention

[0006] The present invention addresses the problems existing in the prior art and provides a method for preparing low-sugar, high-acid potato vinegar. The method solves the problem that an existing pH meter cannot identify the specific reason why the acidity of a fermentation liquid does not increase, and that in the late stage of acetic acid fermentation, as the pH of the fermentation liquid decreases, the protein of the bacterial strain denatures and combines with metal ions to produce insoluble impurities. These impurities are adsorbed on the surface of acid bacteria cells through hydrophobic interaction, destroying the integrity of the phospholipid bilayer and reducing the number of viable bacteria.

[0007] To achieve the above object, the preparation method of the low-sugar, high-acid potato vinegar comprises the following steps:

[0008] S1. Raw material pretreatment: Wash fresh potatoes and crush them into a fine pulp. Then, sieve the pulp to remove the coarse fibers. The sieve aperture should be ≤1mm. The potato pulp is then placed in a jacketed cooking tank and heated to 100°C with steam for 25 minutes to fully gelatinize the starch.

[0009] S2, limited saccharification:

[0010] S2.1. Enzymatic saccharification: The gelatinized potato pulp was cooled to 55°C and transferred to a saccharification tank. 0.15 g / kg of α-amylase and 0.4 g / kg of saccharifying enzyme were added in proportion. The potato pulp was stirred at 130 rpm for 5 hours.

[0011] S2.2, Sugar Content Control: Regularly monitor the reducing sugar content. When the concentration reaches 4.5%, raise the temperature to 85°C to inactivate enzyme activity and stop saccharification, thereby preventing excessive sugar from affecting subsequent acid content.

[0012] S3. Anaerobic fermentation:

[0013] S3.1. Cooling and inoculation: Cool the saccharified liquid to 30°C, adjust the pH to 4.7, inoculate with 0.75% yeast, and transfer to a sealed anaerobic fermentation tank;

[0014] S3.2, Fermentation Control: Maintain the temperature at 30°C and stir at a low speed of 65 rpm for 4 days until the residual sugar content is ≤ 1%, thereby maintaining the low-sugar taste of the potato vinegar;

[0015] S4, aerobic high acid fermentation:

[0016] S4.1. Activation and inoculation of bacteria: Activate acetic acid bacteria, such as Acetobacter pasteurianus, and inoculate 7.5% of the anaerobic fermentation liquid. Transfer the fermentation liquid obtained in S3.2 to an aerobic fermentation device.

[0017] S4.2. Aeration and temperature control: Turn on the aeration system, maintain the ventilation rate at 1:0.5 vvm, maintain the temperature at 32°C, and stir at a high speed of 300 r / min to promote oxygen dissolution;

[0018] S4.3. pH monitoring and control: Real-time pH monitoring is performed using a pH detection device. When the acidity rises above 4g / 100mL, the feed system fine-tunes the amount of nutrients, such as urea, to continue fermentation until the total acidity reaches 7g / 100mL, thereby maintaining a high-acid taste and residual sugar ≤0.5%;

[0019] S5. Post-processing and aging:

[0020] S5.1. Coarse Filtration and Aging: Filter the fermentation broth obtained in S4.3, transfer it to an aging tank, and let it stand at 23°C for 2 months to promote the production of flavor substances;

[0021] S5.2. Remove microorganisms through filtration through a 0.22 μm pore size membrane, pasteurize by maintaining a temperature of 75°C for 20 seconds, and aseptically fill to obtain the finished product;

[0022] The aerobic fermentation device includes a fermentation kettle, which is used to perform aerobic fermentation on the potato pulp fermentation liquid that has completed anaerobic fermentation, that is, to convert the alcohol in the potato pulp into acetic acid through acetic acid bacteria. A dissolved oxygen pump is provided at the center of the bottom of the fermentation kettle for supplying oxygen to the fermentation liquid. A stirring component is provided at the internal axis of the fermentation kettle for stirring the fermentation liquid to promote the dissolution of oxygen therein. An interception component is provided below the stirring component in the fermentation kettle for intercepting impurities. The impurities are mainly insoluble substances produced by the denaturation of proteins in the acetic acid bacteria and the combination with metal ions. A cleaning component for absorbing impurities is provided at a non-central position above the interception component.

[0023] The dissolved oxygen pump can impact the impurities on the top of the interception component from the center to the edge, and the vortex generated by the rotation of the stirring component can drive the impurities on the top edge of the interception component to rotate. In the process of absorbing impurities, the cleaning component can take away solid impurities and filter out the fermentation liquid. The dissolved oxygen pump can drive the fermentation liquid to backwash the interception component to prevent the interception component from being blocked by impurities, and the bottom of the interception component is provided with a groove for gathering the airflow ejected by the dissolved oxygen pump. The angle between the path of the fermentation liquid driven by the dissolved oxygen pump through the interception component and the horizontal plane is between 0° and 90°.

[0024] In the above technical solution, a pH meter for testing the acidity and alkalinity of the fermentation liquid is provided on the inner wall of the fermentation tank. The electrode of the pH meter extends into the fermentation liquid, and the display screen of the pH meter is located outside the fermentation tank for easy reading.

[0025] The improvement lies in the pH meter being positioned at a height of one-third the total depth of the fermentation liquid from the bottom of the fermenter. This location is chosen because it lies within the mainstream flow field of the stirring assembly, where high turbulence eliminates local variations in acidity. When the stirring speed is ≥180 r / min, the concentration deviation in this area is less than 5%. If the pH meter were placed at the bottom of the fermenter or at the surface of the fermentation liquid, bacterial cells or solids would readily settle at the bottom, leading to locally high acidity. Furthermore, near the surface of the fermentation liquid, evaporation and aeration foaming would cause significant pH fluctuations.

[0026] In another technical solution, a peristaltic pump is provided on the top of the fermentation kettle, and the peristaltic pump is used to replenish acetic acid bacteria liquid into the fermentation kettle to increase the acetic acid bacteria content in the fermentation liquid.

[0027] Moreover, a sterile water pump is provided on the top of the fermentation kettle, and the sterile water pump is used to inject sterile water into the fermentation kettle to dilute the concentration of alcohol in the fermentation liquid.

[0028] Based on the above solution, a mounting platform is provided at the axis center of the top of the fermentation kettle, and a main rod is provided inside the fermentation kettle on the mounting platform. A stirring paddle is provided radially of the main rod. The stirring paddle is used to promote the dispersion of oxygen pumped into the fermentation kettle by the dissolved oxygen pump in the fermentation liquid. At the same time, the vortex generated by the stirring paddle drives the impurities on the top of the interception component to rotate along the edge of the interception component. The main rod is driven by a motor, that is, the output shaft of the motor is coaxially connected to the main rod.

[0029] In the above solution, the interception component includes an interception plate integrally provided with the inner wall of the fermentation kettle, and a plurality of filter holes are provided on the interception plate.

[0030] Furthermore, a dispersion slope is provided on the top of the interception plate to prevent the accumulation of impurities, and the groove at the bottom of the interception component includes a dispersion groove opened at the bottom of the interception plate. The upper opening of the filter hole is located on one side of the dispersion slope, and the lower opening of the filter hole is located in the dispersion groove, so that the airflow ejected by the dissolved oxygen pump can be gathered in the dispersion groove, thereby driving the fermentation liquid to backwash the filter hole to prevent it from being blocked by impurities. In addition, since the filter hole is opened at an angle on the interception plate, the dissolved oxygen pump can drive the fermentation liquid to remove the impurities intercepted on the top of the interception plate and flow from the center of the interception plate to the edge.

[0031] Not only that, the cleaning component includes a suction nozzle located above the filter hole, the top of the suction nozzle is connected to a transfer pipe, the cleaning component also includes a slag discharge pipe arranged on the top of the fermentation kettle, the slag discharge pipes of the transfer pipe are connected with a U-shaped pipe, the end of the slag discharge pipe away from the U-shaped pipe is connected to an external extraction pump, the U-shaped pipe is used to extract impurities on the top of the interception plate, and at the same time filter out the fermentation liquid extracted along with the impurities.

[0032] Furthermore, the U-shaped tube includes a tube body, the two openings of the tube body are respectively connected to the slag discharge pipe and the transfer pipe, the opening of the tube body is perpendicular to the axis of the fermentation kettle, and the tube wall of the tube body is downwardly provided with a plurality of drainage holes, each of which is provided with a one-way valve. The one-way valve allows the fermentation liquid extracted along with the impurities to pass through and flow back into the fermentation liquid body in the fermentation kettle, while the impurities pass through the slag discharge pipe and are extracted out of the fermentation kettle by the extraction pump.

[0033] Based on the above description, it can be seen that compared with the prior art, the beneficial effects of the present invention are:

[0034] Insoluble impurities produced during acetic acid fermentation are intercepted by the interception plate. As the dissolved oxygen pump continuously pumps oxygen into the fermentation liquid, these airflows drive the fermentation liquid into the filter holes from the lower opening in the dispersion tank and then flow out from the upper opening on the top of the interception plate, thereby preventing the filter holes from being blocked by impurities. At the same time, the inclined filter holes allow the impurities on the top of the interception plate to flow from the center to the edge.

[0035] When the insoluble impurities reach the edge of the interception plate, they are driven by the vortex generated by the rotation of the agitator to rotate along the edge of the interception plate. When these impurities reach the vicinity of the suction nozzle, the suction force generated by the extraction pump drives the impurities and the fermentation liquid through the transfer pipe into the tube body. The fermentation liquid is recovered into the fermentation liquid body through the drainage hole, while the impurities are blocked by the one-way valve and cannot return to the fermentation liquid body. Therefore, the impurities pass through the slag discharge pipe and are extracted out of the fermentation kettle by the extraction pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0037] Figure 1 This is one of the three-dimensional diagrams of the overall structure of the present invention;

[0038] Figure 2 This is the second perspective view of the overall structure of the present invention;

[0039] Figure 3 It is a partially cutaway perspective view of the present invention;

[0040] Figure 4 It is a partially cutaway front view of the present invention;

[0041] Figure 5 A three-dimensional structural diagram of the stirring assembly of the present invention;

[0042] Figure 6 It is a front structural diagram of the stirring assembly of the present invention;

[0043] Figure 7 is a cutaway perspective view of an interception assembly of the present invention;

[0044] Figure 8 is a cutaway front view of the interception assembly of the present invention;

[0045] Figure 9 is a cutaway perspective view of the cleaning assembly of the present invention;

[0046] Figure 10 It is a cutaway left side view of the cleaning assembly of the present invention;

[0047] Figure 11 For the present invention Figure 10Enlarged view of point A in the middle.

[0048] The meaning of each number in the figure is:

[0049] 101. Fermentation kettle; 102. Mounting table; 103. Sterile water pump; 104. Peristaltic pump; 105. pH meter; 106. Dissolved oxygen pump;

[0050] 200, stirring assembly; 210, main rod; 220, stirring paddle;

[0051] 300, cleaning assembly; 310, suction nozzle; 320, transfer pipe; 330, slag discharge pipe; 340, U-shaped pipe; 341, pipe body; 342, drainage hole; 343, one-way valve;

[0052] 400, interception assembly; 410, interception plate; 420, dispersion slope; 430, filter hole; 440, dispersion trough. DETAILED DESCRIPTION

[0053] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0054] See also Figure 1-Figure 4 As shown, the purpose of this embodiment is to provide a method for preparing low-sugar and high-acid potato vinegar, comprising the following steps:

[0055] S1. Raw material pretreatment: Wash fresh potatoes and crush them into a fine pulp. Then, sieve the pulp to remove the coarse fibers. The sieve aperture should be ≤1mm. The potato pulp is then placed in a jacketed cooking tank and heated to 100°C with steam for 25 minutes to fully gelatinize the starch.

[0056] S2, limited saccharification:

[0057] S2.1. Enzymatic saccharification: The gelatinized potato pulp was cooled to 55°C and transferred to a saccharification tank. 0.15 g / kg of α-amylase and 0.4 g / kg of saccharifying enzyme were added in proportion. The potato pulp was stirred at 130 rpm for 5 hours.

[0058] S2.2, Sugar Content Control: Regularly monitor the reducing sugar content. When the concentration reaches 4.5%, raise the temperature to 85°C to inactivate enzyme activity and stop saccharification, thereby preventing excessive sugar from affecting subsequent acid content.

[0059] S3. Anaerobic fermentation:

[0060] S3.1. Cooling and inoculation: Cool the saccharified liquid to 30°C, adjust the pH to 4.7, inoculate with 0.75% yeast, and transfer to a sealed anaerobic fermentation tank;

[0061] S3.2, Fermentation Control: Maintain the temperature at 30°C and stir at a low speed of 65 rpm for 4 days until the residual sugar content is ≤ 1%, thereby maintaining the low-sugar taste of the potato vinegar;

[0062] S4, aerobic high acid fermentation:

[0063] S4.1. Activation and inoculation of bacteria: Activate acetic acid bacteria, such as Acetobacter pasteurianus, and inoculate 7.5% of the anaerobic fermentation liquid. Transfer the fermentation liquid obtained in S3.2 to an aerobic fermentation device.

[0064] S4.2. Aeration and temperature control: Turn on the aeration system, maintain the ventilation rate at 1:0.5 vvm, maintain the temperature at 32°C, and stir at a high speed of 300 r / min to promote oxygen dissolution;

[0065] S4.3. pH monitoring and control: Real-time pH monitoring is performed using a pH detection device. When the acidity rises above 4g / 100mL, the feed system fine-tunes the amount of nutrients, such as urea, to continue fermentation until the total acidity reaches 7g / 100mL, thereby maintaining a high-acid taste and residual sugar ≤0.5%;

[0066] S5. Post-processing and aging:

[0067] S5.1. Coarse Filtration and Aging: Filter the fermentation broth obtained in S4.3, transfer it to an aging tank, and let it stand at 23°C for 2 months to promote the production of flavor substances;

[0068] S5.2. Remove microorganisms through filtration through a 0.22 μm pore size membrane, pasteurize by maintaining a temperature of 75°C for 20 seconds, and aseptically fill to obtain the finished product;

[0069] The aerobic fermentation device includes a fermentation vessel 101, which is used to perform aerobic fermentation on the potato pulp fermentation liquid that has completed anaerobic fermentation, that is, to convert the alcohol in the potato pulp into acetic acid through acetic acid bacteria. A dissolved oxygen pump 106 is provided at the center of the bottom of the fermentation vessel 101 for supplying oxygen to the fermentation liquid. A stirring assembly 200 is provided at the internal axis of the fermentation vessel 101 for stirring the fermentation liquid to promote the dissolution of oxygen therein. An interception assembly 400 is provided below the stirring assembly 200 in the fermentation vessel 101 for intercepting impurities. The impurities are mainly insoluble substances produced by the denaturation of proteins in the acetic acid bacteria and the combination of metal ions. A cleaning assembly 300 for absorbing impurities is provided at a non-central position above the interception assembly 400.

[0070] The dissolved oxygen pump 106 can impact the impurities on the top of the interception component 400 from the center to the edge, and the vortex generated by the rotation of the stirring component 200 can drive the impurities on the top edge of the interception component 400 to rotate. The cleaning component 300 can take away solid impurities and filter out the fermentation liquid in the process of absorbing impurities. The dissolved oxygen pump 106 can drive the fermentation liquid to backwash the interception component 400 to prevent the interception component 400 from being blocked by impurities, and a groove is provided at the bottom of the interception component 400 for gathering the airflow ejected by the dissolved oxygen pump 106. The angle between the path of the fermentation liquid driven by the dissolved oxygen pump 106 through the interception component 400 and the horizontal plane is between 0° and 90°.

[0071] Continue reading Figure 2 and Figure 4 A pH meter 105 for testing the acidity and alkalinity of the fermentation liquid is provided on the inner wall of the fermentation tank 101. The electrodes of the pH meter 105 extend into the fermentation liquid, and the display screen of the pH meter 105 is located outside the fermentation tank 101 for easy reading.

[0072] The improvement lies in the placement of pH meter 105 at a height of one-third of the total depth of the fermentation liquid from the bottom of fermenter 101. This location is chosen because it is within the mainstream flow field of stirring assembly 200, where high turbulence eliminates local variations in acidity. When the stirring speed is ≥180 r / min, the concentration deviation in this area is less than 5%. If pH meter 105 were placed at the bottom of fermenter 101 or at the surface of the fermentation liquid, bacterial cells or solids would readily accumulate at the bottom, leading to locally high acidity. Furthermore, near the surface of the fermentation liquid, evaporation and aeration foaming would cause significant pH fluctuations.

[0073] During implementation, after the fermentation liquid undergoes anaerobic fermentation, most of the glucose in the fermentation liquid has been converted into alcohol. The fermentation liquid that has completed anaerobic fermentation is then transferred to the fermentation tank 101, and acetic acid bacteria is then inoculated into the fermentation liquid. Activated acetic acid bacteria liquid is taken at a rate of 5%-10% of the volume of the fermentation liquid and inoculated into the fermentation liquid in the fermentation tank 101. For example, 5-10 L of acetic acid bacteria liquid is inoculated into 100 L of fermentation liquid. At this time, the data of the pH meter 105 is read to record the initial pH value of the fermentation liquid. After 24 hours of acetic acid fermentation, the stirring component 200 is turned off and the liquid level is stabilized. The data of the pH meter 105 is then read again to compare whether the pH value of the fermentation liquid has decreased.

[0074] exist Figure 3 and Figure 4 In the embodiment, a peristaltic pump 104 is provided on the top of the fermentation tank 101. The peristaltic pump 104 is used to supply acetic acid bacteria liquid to the interior of the fermentation tank 101 to increase the acetic acid bacteria content in the fermentation liquid.

[0075] In addition, a sterile water pump 103 is provided on the top of the fermentation tank 101. The sterile water pump 103 is used to inject sterile water into the fermentation tank 101 to dilute the concentration of alcohol in the fermentation liquid.

[0076] It should be noted that when the pH meter 105 detects that the acidity of the fermentation liquid has not increased after 24 hours of acetic acid fermentation, that is, the reading of the pH meter 105 has not decreased, first, the sterile water pump 103 is started to inject sterile water into the fermentation tank 101 to dilute the alcohol concentration in the fermentation liquid. The alcohol concentration is preferably diluted to 5%-8% to prevent the high alcohol concentration from inhibiting the activity of acetic acid bacteria. Then, the peristaltic pump 104 is used to replenish the acetic acid bacteria liquid into the fermentation tank 101 to improve the acetic acid fermentation, that is, the efficiency of converting alcohol into acetic acid.

[0077] The advantage of diluting the alcohol concentration before inoculating acetic acid bacteria is that if the acidity hasn't increased due to high alcohol content, then even if you add more acetic acid bacteria to the fermentation broth, the alcohol will inhibit the activity of the bacteria. If the acidity hasn't increased due to insufficient bacteria, then diluting the fermentation broth won't increase the acidity. Regardless of whether the acidity hasn't increased after 24 hours due to high alcohol content or insufficient acetic acid bacteria, diluting the alcohol concentration first can prevent inhibition of acetic acid bacteria activity before inoculating the broth to improve the efficiency of acetic acid fermentation.

[0078] See also Figure 5 and Figure 6 As shown, a mounting platform 102 is provided at the axis center of the top of the fermentation kettle 101, and a main rod 210 is provided on the mounting platform 102 inside the fermentation kettle 101. A stirring paddle 220 is provided radially of the main rod 210. The stirring paddle 220 is used to promote the dispersion of oxygen pumped into the fermentation kettle 101 by the dissolved oxygen pump 106 in the fermentation liquid. At the same time, the vortex generated by the stirring paddle 220 drives the impurities on the top of the interception component 400 to rotate along the edge of the interception component 400. The main rod 210 is driven by a motor, that is, the output shaft of the motor is coaxially connected to the main rod 210.

[0079] It should be noted that after the potato pulp that has undergone anaerobically fermented is transferred into the fermentation kettle 101 and acetic acid bacteria is inoculated into the fermentation liquid, the motor power is turned on to drive the main rod 210 to rotate. The main rod 210 stirs the fermentation liquid to promote the dispersion of acetic acid bacteria and oxygen in the fermentation liquid. At the same time, the vortex generated by the stirring paddle 220 drives the impurities on the top of the interception component 400 to rotate along the edge of the interception component 400. After the impurities rotate to the vicinity of the cleaning component 300, they are extracted by it to the outside of the fermentation kettle 101.

[0080] Next, through Figure 7 and Figure 8 The specific structure of the interception assembly 400 is disclosed. The interception assembly 400 includes an interception plate 410 integrally provided with the inner wall of the fermentation kettle 101 . A plurality of filter holes 430 are formed on the interception plate 410 .

[0081] Furthermore, a dispersion slope 420 is provided on the top of the interception plate 410 for preventing the accumulation of impurities. The groove at the bottom of the interception component 400 includes a dispersion groove 440 opened at the bottom of the interception plate 410. The upper opening of the filter hole 430 is located on one side of the dispersion slope 420, and the lower opening of the filter hole 430 is located in the dispersion groove 440. This allows the airflow ejected by the dissolved oxygen pump 106 to gather in the dispersion groove 440, thereby driving the fermentation liquid to backwash the filter hole 430 to prevent it from being blocked by impurities. In addition, since the filter hole 430 is opened at an angle on the interception plate 410, the dissolved oxygen pump 106 can drive the fermentation liquid to remove the impurities intercepted at the top of the interception plate 410 from the center to the edge of the interception plate 410.

[0082] That is, as the acetic acid fermentation process progresses, the alcohol in the fermentation liquid is converted into acetic acid by acetic acid bacteria, the pH of the fermentation liquid decreases, and the protein of the bacteria is promoted to combine with metal ions and precipitate, producing insoluble impurities. These insoluble impurities are intercepted by the interception plate 410. Since the dissolved oxygen pump 106 continuously pumps oxygen into the fermentation liquid, this airflow drives the fermentation liquid from the lower opening in the dispersion tank 440 into the filter hole 430, and then flows out from the upper opening at the top of the interception plate 410, thereby preventing the filter hole 430 from being blocked by impurities. At the same time, the inclined filter hole 430 allows the impurities on the top of the interception plate 410 to flow from the center to the edge.

[0083] Based on the above description, Figures 9-11 To explain the preferred effect of the cleaning component 300, the cleaning component 300 includes a suction nozzle 310 located above the filter hole 430, and a transfer pipe 320 is connected to the top of the suction nozzle 310. The cleaning component 300 also includes a slag discharge pipe 330 arranged on the top of the fermentation kettle 101, and a U-shaped pipe 340 is connected between the slag discharge pipes 330 of the transfer pipe 320. The end of the slag discharge pipe 330 away from the U-shaped pipe 340 is connected to an external extraction pump. The U-shaped pipe 340 is used to extract impurities on the top of the intercepting plate 410, and at the same time filter out the fermentation liquid extracted along with the impurities.

[0084] Furthermore, the U-shaped tube 340 includes a tube body 341, and the two openings of the tube body 341 are respectively connected to the slag discharge pipe 330 and the transfer pipe 320. The opening of the tube body 341 is perpendicular to the axis of the fermentation tank 101. The tube wall of the tube body 341 is downwardly provided with a plurality of drainage holes 342. Each drainage hole 342 is provided with a one-way valve 343. The one-way valve 343 is used for the fermentation liquid extracted along with the impurities to pass through and flow back into the fermentation liquid body in the fermentation tank 101, while the impurities pass through the slag discharge pipe 330 and are extracted out of the fermentation tank 101 by the extraction pump.

[0085] During operation of the above structure, the protein of the acetic acid bacteria cells is denatured by acetic acid and combines with metal ions to produce insoluble impurities, which fall onto the top of the interception plate 410. The impurities are then driven by the vortex generated by the rotation of the stirring paddle 220 to rotate along the edge of the interception plate 410. When these impurities reach the vicinity of the suction nozzle 310, the suction force generated by the extraction pump drives the impurities and the fermentation liquid through the transfer pipe 320 into the tube body 341. The fermentation liquid is recovered into the fermentation liquid body through the drainage hole 342, while the impurities are blocked by the one-way valve 343 and cannot return to the fermentation liquid body. Therefore, the impurities are extracted from the fermentation kettle 101 through the slag discharge pipe 330 by the extraction pump.

[0086] In summary, the working principle of the present invention is as follows:

[0087] After the fermentation liquid undergoes anaerobic fermentation, most of the glucose in the fermentation liquid has been converted into alcohol. The fermentation liquid that has completed anaerobic fermentation is then transferred to the fermentation tank 101. Acetic acid bacteria are then inoculated into the fermentation liquid. Activated acetic acid bacteria liquid is taken at a rate of 5% to 10% of the volume of the fermentation liquid and inoculated into the fermentation liquid in the fermentation tank 101. At this time, the data from the pH meter 105 is read to record the initial pH value of the fermentation liquid. After 24 hours of acetic acid fermentation, the stirring paddle 220 is turned off and the liquid level is stabilized. The data from the pH meter 105 is then read again to compare whether the pH value of the fermentation liquid has decreased.

[0088] When the pH meter 105 detects that the acidity of the fermentation liquid has not increased after 24 hours of acetic acid fermentation, that is, the reading of the pH meter 105 has not decreased, the sterile water pump 103 is first started to inject sterile water into the fermentation tank 101 to dilute the alcohol concentration in the fermentation liquid to prevent the high alcohol concentration from inhibiting the activity of acetic acid bacteria. Then, the peristaltic pump 104 is used to replenish the acetic acid bacteria liquid into the fermentation tank 101 to improve the efficiency of acetic acid fermentation, that is, the efficiency of converting alcohol into acetic acid.

[0089] As the acetic acid fermentation process progresses, the alcohol in the fermentation liquid is converted into acetic acid by acetic acid bacteria, and the pH of the fermentation liquid decreases, which promotes the combination and precipitation of bacterial proteins and metal ions, resulting in the production of insoluble impurities. These insoluble impurities are intercepted by the interception plate 410. As the dissolved oxygen pump 106 continuously pumps oxygen into the fermentation liquid, this airflow drives the fermentation liquid into the filter hole 430 from the lower opening in the dispersion tank 440 and then flows out from the upper opening at the top of the interception plate 410, thereby preventing the filter hole 430 from being clogged by impurities. At the same time, the inclined filter hole 430 allows impurities on the top of the interception plate 410 to flow from the center to the edge.

[0090] After the insoluble impurities generated above reach the edge of the interception plate 410, they are driven by the vortex generated by the rotation of the stirring paddle 220 to rotate along the edge of the interception plate 410. When these impurities reach the vicinity of the suction nozzle 310, the suction force generated by the extraction pump drives the impurities and the fermentation liquid through the transfer pipe 320 into the tube body 341. The fermentation liquid is recovered into the fermentation liquid body through the drainage hole 342, while the impurities are blocked by the one-way valve 343 and cannot return to the fermentation liquid body. Therefore, the impurities are extracted out of the fermentation kettle 101 through the slag discharge pipe 330 by the extraction pump.

[0091] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely preferred examples of the present invention and are not intended to limit the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and improvements fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing low-sugar, high-acid potato vinegar, characterized in that: The steps include: S1, raw material pretreatment; S2, limited saccharification; S3, anaerobic fermentation; S4, acetic acid fermentation: the fermentation liquid obtained in S3 is transferred to an aerobic fermentation device, and the acetic acid bacteria are activated and inoculated into the fermentation liquid; S5, post-processing and aging; The aerobic fermentation device comprises a fermentation kettle (101), a dissolved oxygen pump (106) is provided at the bottom center of the fermentation kettle (101), a stirring assembly (200) is provided at the internal axis center of the fermentation kettle (101), an interception assembly (400) is provided below the stirring assembly (200) in the fermentation kettle (101), and a cleaning assembly (300) is provided at a non-central position above the interception assembly (400); The dissolved oxygen pump (106) can impact the impurities on the top of the interception component (400) from the center to the edge, the vortex generated by the rotation of the stirring component (200) can drive the impurities on the top edge of the interception component (400) to rotate, and the cleaning component (300) can take away solid impurities and filter out the fermentation liquid in the process of absorbing impurities. The dissolved oxygen pump (106) can drive the fermentation liquid to backwash the interception component (400), and the bottom of the interception component (400) is provided with a groove for gathering the airflow ejected by the dissolved oxygen pump (106). The angle between the path of the fermentation liquid driven by the dissolved oxygen pump (106) through the interception component (400) and the horizontal plane is between 0° and 90°.

2. The method for preparing low-sugar, high-acid potato vinegar according to claim 1, wherein: A pH meter (105) for testing the acidity and alkalinity of the fermentation liquid is provided on the inner wall of the fermentation tank (101).

3. The method for preparing low-sugar, high-acid potato vinegar according to claim 2, wherein: The pH meter (105) is located at a height of one third of the total depth of the fermentation liquid from the bottom of the fermentation tank (101).

4. The method for preparing low-sugar, high-acid potato vinegar according to claim 1, wherein: A peristaltic pump (104) is provided on the top of the fermentation tank (101), and the peristaltic pump (104) is used to replenish acetic acid bacteria liquid into the fermentation tank (101).

5. The method for preparing low-sugar, high-acid potato vinegar according to claim 1, wherein: A sterile water pump (103) is also provided on the top of the fermentation tank (101), and the sterile water pump (103) is used to inject sterile water into the fermentation tank (101).

6. The method for preparing low-sugar, high-acid potato vinegar according to claim 1, wherein: A mounting platform (102) is provided at the axis center of the top of the fermentation kettle (101), and a main rod (210) is provided on the mounting platform (102) inside the fermentation kettle (101). A stirring paddle (220) is provided radially of the main rod (210). The stirring paddle (220) is used to promote the oxygen pumped into the fermentation kettle (101) by the dissolved oxygen pump (106) to be dispersed in the fermentation liquid. At the same time, the vortex generated by the stirring paddle (220) drives the impurities on the top of the interception component (400) to rotate along the edge of the interception component (400).

7. The method for preparing low-sugar, high-acid potato vinegar according to claim 1, wherein: The interception assembly (400) includes an interception plate (410) integrally arranged with the inner wall of the fermentation kettle (101), and a plurality of filter holes (430) are formed on the interception plate (410).

8. The method for preparing low-sugar, high-acid potato vinegar according to claim 7, wherein: A dispersion slope (420) is provided on the top of the interception plate (410) for preventing impurities from accumulating. The groove at the bottom of the interception assembly (400) includes a dispersion groove (440) opened at the bottom of the interception plate (410). The upper opening of the filter hole (430) is located on one side of the dispersion slope (420), and the lower opening of the filter hole (430) is located in the dispersion groove (440). This allows the airflow ejected by the dissolved oxygen pump (106) to be gathered in the dispersion groove (440), thereby driving the fermentation liquid to backwash the filter hole (430) to prevent it from being blocked by impurities.

9. The method for preparing low-sugar, high-acid potato vinegar according to claim 7, wherein: The cleaning assembly (300) includes a suction nozzle (310) located above the filter hole (430), and the top of the suction nozzle (310) is connected to a transfer pipe (320). The cleaning assembly (300) also includes a slag discharge pipe (330) arranged on the top of the fermentation kettle (101), and a U-shaped pipe (340) is connected between the slag discharge pipe (330) of the transfer pipe (320). The end of the slag discharge pipe (330) away from the U-shaped pipe (340) is connected to an external extraction pump. The U-shaped pipe (340) is used to extract impurities on the top of the interception plate (410) and filter out the fermentation liquid extracted along with the impurities.

10. The method for preparing low-sugar, high-acid potato vinegar according to claim 9, characterized in that: The U-shaped tube (340) includes a tube body (341), the two openings of the tube body (341) are respectively connected to the slag discharge pipe (330) and the transfer pipe (320), the opening of the tube body (341) is perpendicular to the axis of the fermentation kettle (101), and the tube wall of the tube body (341) is provided with a plurality of drainage holes (342) facing downward, and each of the drainage holes (342) is provided with a one-way valve (343).

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