Frozen lactic acid bacteria fermented potato juice beverage and method for preparing the same

Abstract

The application discloses a kind of frozen lactic acid bacteria fermented potato juice beverage and preparation method thereof.The method comprises the following steps: after freezing and thawing potato, mixing with water and adding VC beating pulp, ultrasonic treatment, filtering and centrifuging to obtain supernatant, inoculating plant lactobacillus LIP1 and lactobacillus C31 after sterilization, and then compounding and fermenting, and then obtaining finished product after cold storage and maturation.The application can significantly improve the extraction rate of protein and soluble dietary fiber by freezing and ultrasonic treatment to destroy cell structure, effectively inhibit juice browning, remove starch by centrifugation to reduce the glycemic index of product and improve stability, further improve flavor by lactic acid bacteria fermentation, enrich prebiotic oligosaccharides, functional amino acids and antioxidant substances, and comprehensively improve nutritional quality.The method is simple in operation, low in cost and suitable for industrial production.

Description

Technical Field

[0001] This invention relates to the field of fruit and vegetable juice beverage processing technology, specifically to a fermented potato juice beverage and its preparation method, and more particularly to a potato juice beverage and its preparation method that combines freezing-ultrasound combined pretreatment with lactic acid bacteria fermentation. Background Technology

[0002] Potato (Solanum tuberosum L.) is the world's fourth largest food crop, rich in protein, dietary fiber, organic acids, polyphenols, and other bioactive nutrients, possessing high nutritional and processing value. Potato juice, as an intermediate product of potato processing, retains most of the potato's water-soluble nutrients and has good development potential. However, traditional potato juice preparation processes suffer from numerous technical bottlenecks, severely restricting its application in the functional beverage field.

[0003] First, traditional direct pressing methods have limited impact on the cell structure of potatoes, making it difficult to fully release intracellular proteins, dietary fiber, and other nutrients, resulting in low raw material utilization and low product nutritional value. Second, potatoes are prone to enzymatic browning during processing, where polyphenol oxidase catalyzes the oxidation of phenolic substances to produce quinone pigments, severely affecting the product's color and appearance. Furthermore, potato juice often has unpleasant flavors such as earthy, grassy, ​​and beany notes, especially due to the presence of volatile flavor compounds like 2-pentyl-furan and hexanal, leading to poor palatability and low consumer acceptance. Additionally, the high starch content in potato juice not only results in poor product stability and easy sedimentation but also a high glycemic index, making it unsuitable for people with blood sugar sensitivity.

[0004] Lactic acid bacteria fermentation, as a mild bioprocessing technology, can effectively improve the flavor and quality of plant-based raw materials, degrade macromolecular nutrients, and synthesize functional metabolites, and has been widely used in the field of fruit and vegetable juice fermentation. However, the application of lactic acid bacteria fermentation in potato juice is rarely reported, and existing potato fermentation beverages mostly use enzymatic hydrolysis-assisted processes, which are complex and require sophisticated equipment. Therefore, there is an urgent need to develop a simple, low-cost method for preparing potato juice beverages that can simultaneously address multiple issues such as nutrient extraction, browning inhibition, flavor improvement, and product stability. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, the present invention aims to provide a frozen lactic acid bacteria fermented potato juice beverage and its preparation method.

[0006] To achieve the aforementioned objective, the technical solution of the present invention is implemented as follows: a method for preparing a frozen lactic acid bacteria fermented potato juice beverage, comprising the following steps: (1) Wash fresh potatoes, freeze and thaw them, peel them, mix them with water at a certain material-liquid ratio, add VC, and mash them to obtain potato slurry. (2) The potato slurry obtained in step (1) is subjected to ultrasonic treatment; (3) Filter the ultrasonically treated slurry, centrifuge to remove starch, and collect the supernatant, which is potato juice. (4) After sterilizing the potato juice obtained in step (3), inoculate it with a mixed bacterial solution of Lactobacillus plantarum LIP-1 and Lactobacillus casei C3-1 for fermentation. After fermentation to the endpoint, refrigerate and mature to obtain fermented potato juice beverage.

[0007] Preferably, in step (1), the freezing is performed at -18 to -25°C for 6 to 24 hours, and the thawing is performed at 2 to 6°C for 0.5 to 3 hours; the ratio of potato to water is 1:0.5 to 1:2 (w / w); and the amount of VC added is 0.05% to 0.20% (w / w) based on the total mass of the final slurry.

[0008] More preferably, the freezing in step (1) is freezing at -20°C for 12 hours, and the thawing is thawing at 4°C for 1 hour; the ratio of potato to water is 1:0.5 (w / w); and the amount of VC added is 0.15% (w / w) based on the total mass of the final slurry.

[0009] Preferably, the ultrasonic treatment in step (2) has a power of 200-400 W and a duration of 30-50 min.

[0010] More preferably, the ultrasonic treatment in step (2) has a power of 400 W and a time of 40 min.

[0011] Preferably, the filtration in step (3) is performed using a 100-mesh sieve; the centrifugation conditions are 1500-2500 r / min for 3-10 min; and the sterilization is performed at 70-80℃ for 15-30 min.

[0012] More preferably, the centrifugation conditions in step (3) are 2000 r / min for 4 min; the sterilization conditions are 75℃ for 20 min.

[0013] Preferably, in step (3), before sterilization, 0.05% to 0.30% (w / w) of low-ester pectin is added to the total mass of potato juice.

[0014] Preferably, in step (4), the ratio of viable Lactobacillus plantarum LIP-1 to Lactobacillus casei C3-1 is 1:1 to 1:5, the inoculum amount of the mixed bacterial solution is 1% to 5% (v / v), the fermentation temperature is 35 to 45°C, and the final pH of the fermentation is 4.5 to 4.8.

[0015] More preferably, in step (4), the ratio of viable Lactobacillus plantarum LIP-1 to Lactobacillus casei C3-1 is 1:3, the inoculum amount of the mixed bacterial solution is 3% (v / v), the fermentation temperature is 42℃, and the final pH of the fermentation is 4.55 to 4.6.

[0016] Preferably, the post-ripening conditions described in step (4) are refrigeration at 2-6°C for 12-36 hours.

[0017] More preferably, the post-cold ripening conditions described in step (4) are refrigeration at 4°C for 24 hours.

[0018] The *Lactobacillus plantarum* LIP-1 strain used in this invention was isolated from fermented mare's milk in Xinjiang and has a significant effect on lowering blood lipids; *Lactobacillus casei* C3-1 was isolated from naturally fermented mare's milk in Xilingol League, Inner Mongolia and has a significant effect on lowering cholesterol.

[0019] The beneficial effects of this invention are reflected in: (1) The extraction rate of nutrients is significantly improved. Freezing causes water in potato cells to form ice crystals, initially disrupting the cell structure; ultrasonic treatment further mechanically damages the cell wall and cell membrane, promoting the dissolution of nutrients such as intracellular protein and soluble dietary fiber. The sequential freezing and ultrasonic treatment produce a synergistic effect, achieving a 1+1>2 effect. According to the test, the protein extraction rate of potato juice prepared by the method of this invention is 1.19 g / 100 g potato, which is 83.08% higher than that of direct pressing; the soluble dietary fiber extraction rate is 0.87 g / 100 g potato, which is 89.13% higher than that of direct pressing.

[0020] (2) Effectively inhibits juice browning. Freezing and ultrasonic treatment can effectively inactivate the activity of polyphenol oxidase, reduce the occurrence of enzymatic browning reaction, and thus maintain the good color quality of the product.

[0021] (3) Good product stability and low glycemic index. By removing starch by centrifugation, not only is the stability problem of potato juice being prone to stratification and sedimentation solved, but the glycemic index of the product is also effectively reduced, expanding the consumer base of the product; at the same time, the starch separated by centrifugation can be recycled as an industrial raw material, realizing the full utilization of potato resources.

[0022] (4) Significantly improved flavor quality. This invention uses Lactobacillus plantarum LIP-1 and Lactobacillus casei C3-1 for compound fermentation, and the flavor system of potato juice is positively reconstructed after fermentation. 1-Octen-3-ol (mushroom aroma, fungal aroma), which represents the fresh flavor of potatoes, becomes the core dominant flavor of the sample; the contribution of undesirable flavor substances such as 2-pentyl-furan, the main source of earthy and beany flavor, and hexanal and (E,E)-2,6-nonadienal, the source of grassy and astringent flavor, is greatly reduced; at the same time, the flavor contribution of fruity and sweet aroma substances such as heptanal and benzaldehyde is significantly improved, and new floral and fruity sweet aroma substances such as phenylacetaldehyde and benzyl alcohol are added, making the flavor layers fuller and more rounded.

[0023] (5) Comprehensive improvement in nutritional quality. After compound fermentation, the functional nutrients in potato juice are significantly enriched. At the carbohydrate metabolism level, probiotic oligosaccharides such as trehalose, gentiobiose, and fructooligosaccharide, as well as functional sugar acids such as gluconolactone and gluconic acid, are significantly upregulated; at the amino acid metabolism level, the conditionally essential amino acid arginine is significantly upregulated, and the level of the umami amino acid glutamic acid is increased; at the organic acid and functional active substance level, key intermediates of the tricarboxylic acid cycle such as pyruvate and 2-ketoglutarate, as well as antioxidant substances such as caffeic acid, are significantly upregulated. Overall, the product of this invention achieves significant improvements in probiotic function, antioxidant activity, and comprehensive nutritional value.

[0024] (6) The process is simple and the cost is low. This invention does not require complicated enzymatic hydrolysis steps and expensive equipment. It is easy to operate and suitable for industrial production. Attached Figure Description

[0025] In the attached diagram: Figure 1 This is a flowchart of the preparation method of the present invention; Figure 2 The bar chart shows the changes in the extraction amounts of protein and soluble dietary fiber in potato juice before and after freezing-ultrasound treatment. Detailed Implementation

[0026] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the invention, and not all of them. Unless otherwise specified, the embodiments and features described in this application can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0027] Furthermore, "multiple" refers to two or more. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of a person skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the invention.

[0028] Example 1

[0029] (1) Activation of strains: L. plant lactobacillus LIP-1 and L. casei C3-1 were activated for 2 generations and cultured to prepare fermentation agents for later use.

[0030] (2) Wash the fresh potatoes, freeze them at -20℃ for 12 hours, and thaw them at 4℃ for 1 hour. After peeling, take a certain weight of potatoes, mix them with distilled water at a ratio of 1:0.5 (w / w), add 0.15% VC (w / w based on the total mass of the final pulp), and juice them using a juicer for later use.

[0031] (3) The potato slurry was ultrasonically treated at 400 W for 40 min. After the slurry was filtered through a 100-mesh standard nylon screen at normal pressure, the filtrate was centrifuged at 2000 r / min for 4 min to remove starch. The supernatant was collected to obtain potato juice.

[0032] (4) Add 0.15% low-ester pectin (w / w based on the total mass of potato juice) to the potato juice obtained in step (3), mix well, and sterilize at 75°C for 20 min.

[0033] (5) Cool the sterilized potato juice from step (4) to 30-40°C and inoculate it with a starter culture for fermentation. The starter culture is a bacterial solution of Lactobacillus plantarum LIP-1 and Lactobacillus casei C3-1 obtained in step (1) at a live cell ratio of 1:3. The inoculation amount is 3% (v / v), the fermentation temperature is controlled at 42°C, and the pH at the end of fermentation is controlled at 4.55-4.6.

[0034] (6) After cooling the fermented potato juice from step (5), it is fermented in a refrigerator at 4°C for 24 hours to obtain the fermented potato juice beverage.

[0035] Example 2

[0036] (1) Activation of strain: Same as step (1) in Example 1.

[0037] (2) Wash the fresh potatoes, freeze them at -18℃ for 24 hours, and thaw them at 4℃ for 2 hours. After peeling, take a certain weight of potatoes, mix them with distilled water at a ratio of 1:1 (w / w), add 0.10% VC (w / w based on the total mass of the final pulp), and juice them using a juicer for later use.

[0038] (3) The potato slurry was ultrasonically treated at 300 W for 50 min. After the slurry was filtered through a 100-mesh standard nylon screen at normal pressure, the filtrate was centrifuged at 2000 r / min for 5 min to remove starch. The supernatant was collected to obtain potato juice.

[0039] (4) Add 0.20% low-ester pectin (w / w based on the total mass of potato juice) to the potato juice obtained in step (3), mix well, and sterilize at 75°C for 20 min.

[0040] (5) Cool the sterilized potato juice from step (4) to 30-40°C and inoculate it with a starter culture for fermentation. The starter culture is a bacterial solution of Lactobacillus plantarum LIP-1 and Lactobacillus casei C3-1 at a live cell ratio of 1:2. The inoculum amount is 4% (v / v), the fermentation temperature is controlled at 40°C, and the pH at the end of fermentation is controlled at 4.6-4.7.

[0041] (6) After cooling the fermented potato juice from step (5), it is fermented in a refrigerator at 4°C for 36 hours to obtain the fermented potato juice beverage.

[0042] Example 3

[0043] (1) Activation of strain: Same as step (1) in Example 1.

[0044] (2) Wash the fresh potatoes, freeze them at -25℃ for 8 hours, and thaw them at 4℃ for 1.5 hours. After peeling, take a certain weight of potatoes, mix them with distilled water at a ratio of 1:1.5 (w / w), add 0.18% VC (w / w based on the total mass of the final pulp), and blend them with a juicer for later use.

[0045] (3) The potato slurry was ultrasonically treated at 250 W for 35 min. After the slurry was filtered through a 100-mesh standard nylon screen at normal pressure, the filtrate was centrifuged at 1800 r / min for 6 min to remove starch. The supernatant was collected to obtain potato juice.

[0046] (4) Add 0.10% low-ester pectin (w / w based on the total mass of potato juice) to the potato juice obtained in step (3), mix well, and sterilize at 70°C for 25 min.

[0047] (5) Cool the sterilized potato juice from step (4) to 30-40°C and inoculate it with a starter culture for fermentation. The starter culture is a bacterial solution of Lactobacillus plantarum LIP-1 and Lactobacillus casei C3-1 at a live cell ratio of 1:4. The inoculation amount is 2% (v / v), the fermentation temperature is controlled at 37°C, and the pH at the end of fermentation is controlled at 4.7-4.8.

[0048] (6) After cooling the fermented potato juice from step (5), it is fermented in a refrigerator at 4°C for 12 hours to obtain the fermented potato juice beverage.

[0049] Experimental Example 1: Protein Content Determination Follow the BCA kit instructions. Prepare the BCA working solution by mixing BCA reagent A and reagent B at a 5:1 ratio. Take 0.025 mL of diluted direct-pressed potato juice sample and the frozen-ultrasonic treated potato juice sample prepared in Example 1, add 0.2 mL of the working solution, mix well, and incubate at 37℃ for 25 min. Measure the absorbance at 562 nm. Simultaneously, prepare standard protein solutions at concentrations of 0, 25, 125, 250, 500, 750, 1000, 1500, and 2000 μg / mL, and perform the same procedure. The linear regression equation for the standard protein solution satisfies R0. 2 If the value is ≥0.99, multiply the measurement result by the dilution factor to obtain the protein content.

[0050] The results are as follows Figure 1 As shown in Table 3, after freeze-ultrasound treatment, the protein extraction rate in potato juice was 1.19 g / 100 g potato, which was 83.08% higher than that of the direct pressing control group (0.65 g / 100 g potato).

[0051] Table 3. Extraction amounts of protein and dietary fiber from potato juice before and after freezing-ultrasound treatment.

[0052] Experimental Example 2: Determination of Soluble Dietary Fiber Content The content of soluble dietary fiber in potato juice obtained by direct pressing and frozen-ultrasonic treatment was determined by enzyme-gravimetric method.

[0053] The results are as follows Figure 1 As shown in Table 3, the soluble dietary fiber content in the samples significantly increased after freeze-sonic treatment, with an extraction yield of 0.87 g / 100 g potato, which was 89.13% higher than that of the direct pressing control group (0.46 g / 100 g potato).

[0054] Experimental Example 3: Flavor Analysis Before and After Fermentation The flavor compounds of potato juice before and after fermentation were qualitatively and quantitatively analyzed by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS), and the relative odor activity (rOAV) was calculated. The results are shown in Table 1.

[0055] Table 1. Statistical results of key flavor active substances (rOAV ≥ 1) in potato juice before and after lactic acid bacteria fermentation.

[0056] Note: "-" indicates that the substance rOAV < 1 and has no core contribution to flavor; rOAV ≥ 1 is a key flavor active substance, and a value of 100 indicates the characteristic substance with the greatest flavor contribution in this group.

[0057] In the control group (unfermented) potato juice, 2-pentyl-furan (the core source of earthy and beany flavor, rOAV=100) was the dominant flavor compound. Hexanal (a grassy and astringent flavor), (E,E)-2,6-nonadienal (a raw and green flavor), (E)-2-pentenal and other undesirable raw and astringent flavor compounds were the core contributing components, resulting in prominent off-flavors and poor palatability of the sample.

[0058] In the treatment group (potato juice after fermentation in Example 1), the flavor system underwent positive reconstruction: 1-octen-3-ol (mushroom aroma, fungal aroma), representing the fresh flavor characteristic of potatoes, increased to 100, becoming the core dominant flavor of the sample; the contribution of undesirable flavor substances was greatly reduced, 2-pentyl-furan rOAV decreased from 100 to 68.53, hexanal decreased from 9.24 to 2.07, (E,E)-2,6-nonadienal decreased from 55.55 to 4.54, and (E)-2-pentenal and (Z)-4-heptenal decreased to the level of no core contribution (rOAV<1). Meanwhile, the treatment group significantly improved the flavor contribution of fruity and sweet aroma compounds such as heptanal (rOAV increased from 2.55 to 4.58) and benzaldehyde (rOAV increased from 1.05 to 3.31), and added four new floral and sweet aroma compounds that had no core contribution in the control group, namely phenylacetaldehyde (rOAV=4.37), benzyl alcohol (rOAV=9.46), 2-methoxyphenol (rOAV=1.50), and hexyl acetate (rOAV=1.18), resulting in a fuller and more rounded flavor profile.

[0059] Overall, after compound fermentation, the potato juice effectively weakened unpleasant flavors and enhanced pleasant flavors, resulting in a comprehensive improvement in flavor quality.

[0060] Experimental Example 4: Nutritional Composition Analysis Before and After Fermentation Untargeted metabolomics analysis of potato juice metabolites before and after fermentation was performed using ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS / MS), and the results are shown in Table 2.

[0061] Table 2. Differential metabolites and their up- and down-regulation in potato juice before and after lactic acid bacteria fermentation.

[0062] After compound fermentation, the functional nutrients in potato juice are significantly enriched: At the carbohydrate metabolism level: reducing sugars such as glucose were downregulated (FC=0.5048), providing substrates for strain reproduction and the synthesis of functional substances; trehalose (FC=2717.47), gentiobiose (FC=618.90), and fructotriose (FC=6.57×10) were also downregulated. 6 Probiotic oligosaccharides such as , and gluconolactone (FC=5.63×10) 7 Functional sugar acids such as fructose-1,6-bisphosphate (FC=2.35) were all significantly upregulated (P<0.01); fructose-1,6-bisphosphate (FC=3.43×10⁻⁶) was also significantly upregulated. 7 The significant upward adjustment confirms that the sugar metabolism pathway in the fermentation system is relatively active.

[0063] At the level of amino acid metabolism: the conditionally essential amino acid arginine was significantly upregulated (FC = 3.25 × 10⁻⁶). 9 P < 0.01); umami amino acid glutamic acid was upregulated (FC = 1.16); creatine (FC = 148.45), creatinine (FC = 64.95), and pyroglutamic acid (FC = 7.00 × 10⁻⁶) were also upregulated. 6 Functional amino acid derivatives such as ) all maintained a highly significant upregulation trend (P<0.05).

[0064] At the level of organic acids and functional active substances: key intermediates of the tricarboxylic acid cycle, such as pyruvate (FC=30.92, P<0.01) and 2-ketoglutarate (FC=15.06, P<0.01), were significantly upregulated; antioxidants such as caffeic acid (FC=3.49, P<0.01) were significantly upregulated.

[0065] Overall, the fermentation of compound strains achieved targeted enrichment of functional nutrients in potato juice, with significant optimization in probiotic functions, antioxidant activity, and flavor quality, effectively enhancing the comprehensive nutritional value of the product.

[0066] In summary, the potato juice beverage prepared by the frozen-ultrasonic combined lactic acid bacteria fermentation method provided by this invention has significant improvements over traditional methods in terms of nutrient extraction, product stability, flavor quality, and nutritional quality, and has good prospects for industrial application.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0068] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0069] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a frozen lactic acid bacteria fermented potato juice beverage, characterized in that, Includes the following steps: (1) After freezing and thawing potatoes, mix them with water, add vitamin C, and blend to obtain potato pulp; (2) The potato slurry obtained in step (1) is subjected to ultrasonic treatment; (3) Filter the ultrasonically treated slurry, centrifuge it, collect the supernatant, and sterilize it; (4) Inoculate the supernatant after sterilization in step (3) with a mixed bacterial culture of Lactiplantibacillusplantarum LIP-1 and Lactobacillus casei C3-1 for fermentation. After fermentation to the endpoint, refrigerate and mature to obtain fermented potato juice beverage.

2. The preparation method according to claim 1, characterized in that, The freezing in step (1) is freezing at -18 to -25°C for 6 to 24 hours, and the thawing is thawing at 2 to 6°C for 0.5 to 3 hours.

3. The preparation method according to claim 1, characterized in that, The ratio of potato to water in step (1) is 1:0.5 to 1:2 (w / w), and the amount of VC added is 0.05% to 0.20% (w / w) based on the total mass of the final slurry.

4. The preparation method according to claim 1, characterized in that, The ultrasonic treatment in step (2) has a power of 200-400 W and a time of 30-50 min.

5. The preparation method according to claim 1, characterized in that, The filtration in step (3) uses a 100-mesh sieve, the centrifugation conditions are 1500-2500 r / min for 3-10 min, and the sterilization is 70-80℃ for 15-30 min.

6. The preparation method according to claim 1, characterized in that, In step (4), the ratio of viable Lactobacillus plantarum LIP-1 to Lactobacillus casei C3-1 is 1:1 to 1:5, the inoculation amount of the mixed bacterial solution is 1% to 5% (v / v), the fermentation temperature is 35 to 45℃, and the final pH of the fermentation is 4.5 to 4.

8.

7. The preparation method according to claim 1, characterized in that, The conditions for post-cold ripening described in step (4) are refrigeration at 2-6°C for 12-36 hours.

8. The preparation method according to claim 1, characterized in that, In step (3), before sterilization, 0.05% to 0.30% (w / w) of low-ester pectin is added to the total mass of potato juice.

9. The preparation method according to any one of claims 1 to 8, characterized in that, The material-to-liquid ratio in step (1) is 1:0.5 (w / w), and the amount of VC added is 0.15% (w / w); the ultrasonic power in step (2) is 400 W, and the time is 40 min; the centrifugation conditions in step (3) are 2000 r / min for 4 min, and sterilization is 75℃ for 20 min; the ratio of viable bacteria of *Lactobacillus plantarum* to *Lactobacillus casei* in step (4) is 1:3, the inoculum amount is 3% (v / v), the fermentation temperature is 42℃, and the final pH of fermentation is 4.55~4.6; the post-ripening after refrigeration is refrigerated at 4℃ for 24 hours.

10. A frozen lactic acid bacteria fermented potato juice beverage prepared by any one of claims 1 to 9.

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