Citrus beverage based on probiotic fermentation and preparation technology thereof

Abstract

The invention belongs to the technical field of fermentation, and particularly relates to a citrus beverage based on probiotic fermentation and a preparation process thereof. The preparation technology of the fermented citrus beverage based on the probiotics comprises the following steps: S1, pretreating raw material juice to obtain a fermentation base solution; s2, inoculating; s3, fermenting to obtain fermentation liquor; and S4, carrying out post-treatment. Bitter substances are directionally degraded through a compound enzyme preparation, synergistic fermentation is performed by adopting a compound acid-resistant strain, and substrate optimization, staged temperature-controlled fermentation and low-temperature post-treatment technologies are combined, so that the content of naringin and limonin is remarkably reduced, the retention rate of total phenols and total flavonoids and the survival rate of probiotics are increased, and the content of the bitter substances is increased. The prepared citrus beverage has excellent flavor, nutrition and health care value and stability.

Description

Technical Field

[0001] The invention belongs to the technical field of fermentation, and in particular relates to a citrus beverage based on probiotic fermentation and a preparation process thereof. Background Art

[0002] Probiotic beverages are widely popular for their health benefits, including regulating intestinal flora and boosting immunity. Currently, probiotic beverages on the market are primarily based on dairy products like yogurt and lactic acid bacteria beverages, or fermented grains. Citrus beverages are popular among consumers for their rich vitamin C and bioactive ingredients, but existing preparation processes present numerous challenges.

[0003] Bitter substances like naringin and limonin in citrus fruits are difficult to effectively remove, and traditional single-enzymatic or chemical debittering methods easily destroy nutrients. Probiotics have a low survival rate in the acidic environment of citrus fruits, and high-temperature processing and storage further lead to a sharp drop in viable bacteria counts, making it difficult to achieve sustained health benefits. Furthermore, high-temperature sterilization and rough handling in traditional processes lead to a significant loss of heat-sensitive ingredients like vitamin C, making the product prone to precipitation and stratification, and poor stability. Furthermore, existing products often rely on single-strain fermentation, resulting in limited functionality and insufficient flavor coordination, failing to meet consumer demand for high-quality, multifunctional health drinks.

[0004] Therefore, it is of great significance to develop a citrus beverage preparation process that can efficiently remove bitterness, increase probiotic survival rate, retain nutrients well and have excellent stability. Summary of the Invention

[0005] The purpose of the present invention is to provide a citrus beverage based on probiotic fermentation and a preparation process thereof, which significantly reduces the content of naringin and limonin, improves the retention rate of total phenols and total flavonoids and the survival rate of probiotics, so that the prepared citrus beverage has excellent flavor, nutritional and health value and stability.

[0006] A preparation process of a citrus beverage based on probiotic fermentation comprises the following steps: S1, pretreatment of raw juice to obtain fermentation bottom liquid; S2, vaccination; S3, fermentation to obtain fermentation liquid; S4. Post-processing.

[0007] Preferably, in step S1, the specific steps of pre-treating the raw juice are: squeezing the citrus juice, passing it through an 80-150 mesh sieve to obtain the citrus raw juice, adding an enzyme preparation for enzymatic hydrolysis, adding a sugar source and stirring evenly, adjusting the pH to 4.2-4.8, pasteurizing, and cooling to 30-32°C.

[0008] Preferably, the enzyme preparation comprises naringinase, β-glucosidase, cellulase, and neutral protease.

[0009] Preferably, the added amount of the enzyme preparation is 130-200 U / mL citrus juice.

[0010] Preferably, the ratio of the added amounts of naringinase, β-glucosidase, cellulase and neutral protease is (3-5): (1-3): (1-2): 1.

[0011] By selecting a combination of several specific enzymes, it is possible to target the degradation of bitter substances, increase the efficiency of releasing nutritional active ingredients, and improve the flavor and taste. This may be because, on the one hand, through the synergistic action of naringinase and β-glucosidase, the molecular structure of bitter substances is directionally broken, reducing the content of bitter substances from the source. On the other hand, cellulase destroys the structure of citrus cell walls, and neutral proteases break down proteins bound to pectin. The two synergistically destroy the cell structure, promote the release of fat-soluble active ingredients such as total phenols and total flavonoids in the cells, and reduce the interference of protein impurities on flavor. By optimizing the compound ratio of the four enzymes, the content of naringin and limonin in beverages can be significantly reduced, the content of total phenols and total flavonoids can be increased, and the basic flavor base can be improved.

[0012] Preferably, the specific steps of the enzymatic hydrolysis are: first adding naringinase, β-glucosidase, and cellulase, and performing enzymatic hydrolysis for 1-2 hours at a pH of 4.0 and a temperature of 40-50° C., with a stirring speed of 40-60 rpm, and then adjusting the pH to 6.5-7.5, maintaining the temperature and stirring speed unchanged, and performing enzymatic hydrolysis for 45-60 minutes.

[0013] Preferably, the sugar source is fructooligosaccharide or inulin.

[0014] Preferably, the added amount of the sugar source is 2%-6% of the mass of the citrus juice.

[0015] Preferably, the specific conditions of the pasteurization are: temperature of 85-90° C. and time of 1-3 minutes.

[0016] Preferably, in step S2, the specific step of inoculation is: inoculating the composite probiotic starter into the fermentation base liquid.

[0017] Preferably, the composite probiotic fermentation agent includes Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus acidophilus.

[0018] Preferably, the inoculation amount of the composite probiotic fermentation agent is 1×10 7 -5×10 7 CFU / mL fermentation base liquid.

[0019] Preferably, the inoculum ratio of Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus acidophilus is (4-6):(3-5):1; more preferably, it is 5:4:1.

[0020] By selecting specific probiotic strains as fermentation agents, the survival stability of probiotics can be enhanced, and the nutritional and health functions of citrus beverages can be strengthened. This may be because all three bacteria can survive under acidic conditions, and the three work together to form an acid-resistant synergistic system. The organic acids produced by the metabolism of Lactobacillus plantarum can maintain the pH stability of the system, providing a suitable growth environment for Lactobacillus rhamnosus and Lactobacillus acidophilus; the extracellular polysaccharides secreted by Lactobacillus rhamnosus can wrap the bacteria, reducing the damage to the cell structure caused by acidic conditions; Lactobacillus acidophilus inhibits the growth of miscellaneous bacteria by competing for nutrients. By optimizing the compound ratio of the three probiotic strains and improving the mutualistic effect between bacteria, not only the survival stability of probiotics during fermentation and storage is significantly improved, but also the acid-resistant strains reduce vitamin C oxidation at low pH, thereby increasing the vitamin C retention rate. In addition, the antioxidant enzymes produced by the metabolism of the strains can protect phenolic substances from oxidation, improve the stability of nutritional and health substances such as total phenols, total brass, and total phenols, and reduce their loss rate, thereby ensuring the intestinal regulatory function.

[0021] Preferably, in step S3, the fermentation is a two-stage temperature-controlled fermentation, and the specific fermentation steps are: in the first stage, microaerobic fermentation is carried out at 30-32°C for 18-24 hours. When the pH drops to 3.8-4.2, oligofructose is added, the temperature is lowered to 20-25°C, and the second stage is entered, anaerobic fermentation is carried out at 20-25°C for 12-24 hours, and the temperature is rapidly cooled to 4-10°C to terminate the fermentation.

[0022] Preferably, the dissolved oxygen concentration during the microaerobic fermentation is controlled to be 0.2-0.4 mg / L.

[0023] Preferably, the supplementary amount of the oligofructose is 3%-5% of the mass of the fermentation base liquid.

[0024] The two-stage temperature control during the fermentation process improves fermentation efficiency, regulates the accumulation of flavor and active ingredients, improves taste harmony, and increases total phenolic and flavonoid content. This is because in the first stage, Lactobacillus plantarum and Lactobacillus acidophilus rapidly proliferate, producing large amounts of acid and initiating the degradation of bitter substances. When the pH drops to 3.8-4.2, supplementation with oligofructose prevents the bacteria from entering a period of decline due to carbon deficiency. The second, lower-temperature stage then begins. The low temperature environment inhibits acid production and reduces the astringency caused by over-acidification. At the same time, Lactobacillus rhamnosus is more likely to synthesize flavor substances such as esters at low temperatures, imparting a refreshing aroma to the beverage. Furthermore, the increased permeability of the cell membrane at low temperatures promotes the dissolution of phenolic and flavonoid substances in citrus fruits. This staged temperature control achieves the orderly progression of "efficient bitterness removal, flavor balance, and active ingredient accumulation."

[0025] Preferably, in step S4, the specific steps of post-processing are: centrifuging the fermentation broth at low temperature, collecting the centrifuge, adding a natural stabilizer, stirring evenly, aseptically filtering through a 0.22 μm membrane, low-temperature pasteurizing, rapidly cooling to 2-8° C., and refrigerating to obtain the citrus beverage.

[0026] Preferably, the specific conditions of the low-temperature centrifugation are: temperature of 4-10°C, rotation speed of 3000-5000 r / min, and time of 10-20 min.

[0027] Through a gentle post-processing process, probiotic loss is reduced, probiotic activity is guaranteed, centrifugal sedimentation rates are lowered, and product stability is improved. Low-temperature centrifugation removes large impurities while preventing thermal damage to probiotics caused by high temperatures. High-fat pectin and gellan gum are used as natural stabilizers. High-fat pectin combines with calcium ions in citrus to enhance gel strength, while gellan gum increases system viscosity. The two synergistically form a three-dimensional gel network that encapsulates tiny particles and reduces precipitation. Low-temperature pasteurization inactivates bacteria while maximizing probiotic activity. The gentle post-processing process uses low temperatures throughout the entire process, from physical separation to sterilization, ensuring both probiotic activity and product stability.

[0028] Preferably, the natural stabilizer includes one or more of high ester pectin and gellan gum.

[0029] Preferably, the mass ratio of the high-fat pectin to gellan gum is (7-9):1.

[0030] Preferably, the amount of the natural stabilizer added is 0.1%-0.3% of the mass of the centrifuge.

[0031] Preferably, the specific conditions for the low-temperature pasteurization are: temperature of 60-65° C., time of 10-20 seconds.

[0032] Through enzymatic hydrolysis, fermentation, and post-processing, the synergistic optimization of the flavor, nutrition, and stability of citrus beverages is achieved through multi-step linkage. The efficient debittering of the complex enzyme preparation lays a good flavor foundation for subsequent fermentation; the complex acid-resistant bacteria efficiently proliferate under optimized substrate and fermentation conditions, and their metabolites assist in the enzymatic hydrolysis of residual bitter substances; staged fermentation coordinates the acid production rate with the accumulation of flavor substances; and mild post-processing preserves the activity of probiotics while fixing the nutrients through stabilizers. Each link forms a closed-loop synergistic effect of "debittering-proliferation-life preservation-stabilization," ultimately achieving a comprehensive improvement in product flavor, nutrition, and stability.

[0033] The citrus beverage is prepared by the preparation process of the citrus beverage based on probiotic fermentation.

[0034] Compared with the prior art, the advantages and beneficial effects of the present invention are: 1. The present invention provides a citrus beverage fermented with probiotics. The beverage uses a composite enzyme preparation to target the degradation of bitter substances, adopts a composite acid-resistant bacterial strain for collaborative fermentation, and combines substrate optimization, staged temperature-controlled fermentation, and low-temperature post-treatment technology to significantly reduce the content of naringin and limonin, improve the retention rate of total phenols and total flavonoids, and improve the survival rate of probiotics. The resulting citrus beverage has excellent flavor, nutritional and health value, and stability.

[0035] 2. The present invention selects several specific enzyme compounds to target the degradation of bitter substances, improve the release efficiency of nutritional active ingredients, and improve flavor and taste.

[0036] 3. The present invention can enhance the survival stability of probiotics and strengthen the nutritional and health functions of citrus beverages by selecting concentrated and specific probiotic strains as fermentation agents.

[0037] 4. The present invention uses two-stage temperature-controlled fermentation during the fermentation process, which can improve fermentation efficiency, directionally regulate the accumulation of flavor substances and active ingredients, improve taste coordination, and increase the content of total phenols and total flavonoids.

[0038] 5. The present invention reduces the loss of probiotics through a mild post-treatment process, ensures the activity of probiotics, reduces the centrifugal sedimentation rate, and improves product stability. DETAILED DESCRIPTION

[0039] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0040] The raw materials described in the present invention are all commercially available, and are specifically as follows: Naringinase, enzyme activity about 100 U / mg; β-glucosidase, enzyme activity about 100 U / g; cellulase, enzyme activity about 50 U / mg; neutral protease, enzyme activity about 100 U / mg; oligofructose; inulin; gellan gum; all from Shanghai Macklin Reagent.

[0041] High-fat pectin, from Jiangsu Yuanzhiyuan Biotechnology Co., Ltd.

[0042] Lactobacillus plantarum, strain number CICC 25125; Lactobacillus rhamnosus, strain number CICC 6137; Lactobacillus acidophilus, strain number CICC 6091; all from the China Industrial Microbiology Culture Collection Center.

[0043] Example 1

[0044] This embodiment provides a preparation process for a citrus beverage based on probiotic fermentation, comprising the following steps: S1, pretreatment of raw juice to obtain fermentation bottom liquid; S2, vaccination; S3, fermentation to obtain fermentation liquid; S4. Post-processing.

[0045] In step S1, the specific steps of pre-treating the raw juice are: squeezing the citrus juice, passing it through a 100-mesh sieve to obtain the citrus raw juice, adding an enzyme preparation for enzymatic hydrolysis, adding a sugar source, stirring evenly, adjusting the pH to 4.5, pasteurizing, and cooling to 30°C.

[0046] The added amount of the enzyme preparation is 170 U / mL citrus juice.

[0047] The enzyme preparation comprises naringinase, beta-glucosidase, cellulase and neutral protease, and the addition ratio is 4:2:1.5:1.

[0048] The specific steps and conditions of the enzymatic hydrolysis are as follows: first, naringinase, β-glucosidase, and cellulase are added; the enzymatic hydrolysis time is 1.5 hours under the conditions of pH 4.0 and temperature 45° C., and the stirring speed is 50 rpm; then, the pH is adjusted to 7, the temperature and stirring speed are kept unchanged, and the enzymatic hydrolysis is carried out for 50 minutes.

[0049] The sugar source is fructooligosaccharide.

[0050] The added amount of the sugar source is 4% of the mass of the citrus juice.

[0051] The specific conditions of the pasteurization are: temperature of 85° C. and time of 2 minutes.

[0052] In step S2, the specific step of inoculation is: inoculating the composite probiotic starter into the fermentation base liquid.

[0053] The composite probiotic fermentation agent comprises Lactobacillus plantarum, Lactobacillus rhamnosus and Lactobacillus acidophilus, and the inoculation ratio is 5:4:1.

[0054] The inoculation amount of the composite probiotic fermentation agent is 2.5×10 7 CFU / mL fermentation base liquid.

[0055] In step S3, the fermentation is a two-stage temperature-controlled fermentation, and the specific fermentation steps are: in the first stage, microaerobic fermentation is carried out at 30°C for 20 hours. When the pH drops to 4.0, oligofructose is added, the temperature is lowered to 22°C, and the second stage is entered, anaerobic fermentation is carried out at 22°C for 18 hours, and the temperature is quickly cooled to 4°C to terminate the fermentation.

[0056] The dissolved oxygen concentration during the microaerobic fermentation was controlled to be 0.3 mg / L.

[0057] The supplementary amount of the oligofructose is 4% of the mass of the fermentation base liquid.

[0058] In step S4, the specific steps of post-processing are: centrifuging the fermentation liquid at low temperature, collecting the centrifuge, adding a natural stabilizer, stirring evenly, aseptically filtering through a 0.22 μm membrane, low-temperature pasteurizing, rapidly cooling to 4° C., and refrigerating to obtain the citrus beverage.

[0059] The specific conditions of the low-temperature centrifugation are: temperature of 4° C., rotation speed of 4000 r / min, and time of 15 min.

[0060] The natural stabilizers are high ester pectin and gellan gum, with a mass ratio of 8:1.

[0061] The added amount of the natural stabilizer is 0.2% of the mass of the centrifuge liquid.

[0062] The specific conditions of the low-temperature pasteurization are: temperature of 60° C. and time of 15 seconds.

[0063] Example 2

[0064] The difference between this embodiment and embodiment 1 is that the enzyme preparation comprises naringinase, β-glucosidase, cellulase, and neutral protease, and the addition ratio is 4:3:1:1.

[0065] Comparative Example 1 The difference between this comparative example and Example 1 is that the enzyme preparation comprises naringinase, cellulase and neutral protease, and the addition ratio is 4:1.5:1.

[0066] Comparative Example 2 The difference between this comparative example and Example 1 is that the enzyme preparation comprises naringinase, β-glucosidase, cellulase, and neutral protease, and the addition ratio is 7:1:1:1.

[0067] Comparative Example 3 The difference between this comparative example and Example 1 is that the enzyme preparation is naringinase.

[0068] Comparative Example 4 The difference between this comparative example and Example 1 is that the composite probiotic fermentation agent is Lactobacillus plantarum.

[0069] Comparative Example 5 The difference between this comparative example and Example 1 is that the composite probiotic fermentation agent is Lactobacillus plantarum and Lactobacillus rhamnosus, and the inoculation ratio is 5:4.

[0070] Comparative Example 6 The difference between this comparative example and Example 1 is that the composite probiotic fermentation agent contains Lactobacillus plantarum, Lactobacillus rhamnosus, and Lactobacillus acidophilus, and the inoculation ratio is 8:1:1.

[0071] Comparative Example 7 The difference between this comparative example and Example 1 is that in step S3, the specific fermentation steps are: in the first stage, microaerobic fermentation is carried out at 30° C. for 38 hours, and then the fermentation is terminated by rapid cooling to 4° C.

[0072] Comparative Example 8 The difference between this comparative example and Example 1 is that in step S4, the specific steps of post-treatment are: centrifuging the fermentation broth at low temperature, collecting the centrifuge, adding a natural stabilizer, stirring evenly, aseptically filtering through a 0.22 μm membrane, pasteurizing, rapidly cooling to 4° C., and refrigerating to obtain a citrus beverage.

[0073] The specific conditions of the pasteurization are: temperature of 85° C. and time of 30 seconds.

[0074] Performance Testing Refer to the method in patent CN 108308481B to test the polyphenol content in citrus beverages. Also, test the naringin and limonin content in citrus juice and citrus beverages. Calculate the naringin and limonin removal rates using the formula: (Content of a substance in citrus juice - Content of a substance in citrus beverage) / Content of a substance in citrus juice × 100%. Refer to GB / T 20574-2006 to test the total flavonoid content in citrus beverages. Refer to GB 5009-2016 to test the vitamin C content in citrus juice and citrus beverages. Calculate the vitamin C retention rate: (Vitamin C content in citrus beverage / Vitamin C content in citrus juice) × 100%. Refer to GB 4789-2016 to test the viable probiotic count in citrus beverages. Stability test: Take 10 mL of sample and centrifuge at 4000 rpm for 20 min at 4°C. Discard the supernatant and dry the precipitate at 105°C to constant weight. Calculate the precipitation rate = (precipitate mass / sample mass) × 100%. Results are shown in Table 1.

[0075] Table 1 Measurement results Total phenols / (mg / L) Naringin removal rate / % Limonin removal rate / % Total flavonoids / (mg / L) Probiotics / (CFU / mL) VC retention rate / % Sedimentation rate / % Example 1 985 88.8 86.9 356 <![CDATA[2.8×10 9 ]]> 91.5 2.1 Example 2 1020 90.3 88.9 372 <![CDATA[2.7×10 9 ]]> 91.0 2.3 Comparative Example 1 810 66.2 60.5 285 <![CDATA[2.5×10 9 ]]> 89.7 3.0 Comparative Example 2 745 74.9 71.8 262 <![CDATA[1.8×10 9 ]]> 85.2 4.8 Comparative Example 3 680 45.8 49.8 198 <![CDATA[2.1×10 9 ]]> 82.3 6.3 Comparative Example 4 752 88.1 85.8 238 <![CDATA[6.3×10 7 ]]> 90.2 8.7 Comparative Example 5 795 87.2 83.7 275 <![CDATA[1.2×10 8 ]]> 88.4 5.4 Comparative Example 6 730 86.5 81.8 221 <![CDATA[3.5×10 7 ]]> 84.6 12.5 Comparative Example 7 795 87.5 84.2 265 <![CDATA[9.8×10 7 ]]> 86.3 5.2 Comparative Example 8 805 88.3 86.3 278 <![CDATA[2.1×10 7 ]]> 73.6 3.5 According to statistics, the probiotic fermentation-based citrus beverages prepared in Examples 1 and 2 of the present invention have high contents of total phenols and total flavonoids, high numbers of viable probiotic bacteria, and high vitamin C retention rates, indicating that the prepared citrus beverages have excellent nutritional and health value; at the same time, the removal rate of bitter substances such as naringin and limonin is high, which helps to improve the flavor; in addition, the sedimentation rate in the centrifugal sedimentation test is low, indicating that the product prepared by the present invention has high stability. Comparative Example 1 lacks β-glucosidase; Comparative Example 2 has an imbalanced enzyme ratio; Comparative Example 3 is treated with only naringinase; Comparative Example 4 uses only plant lactobacillus; Comparative Example 5 lacks Lactobacillus acidophilus; Comparative Example 6 has an imbalanced ratio of composite probiotic fermentation agents; Comparative Example 7 uses a one-stage constant temperature fermentation; Comparative Example 8 uses high-temperature pasteurization in the post-treatment of step S4. The prepared citrus beverages have low contents of total phenols, total flavonoids, and probiotics, low VC retention rate, poor nutritional value, low removal rates of naringin and limonin, bitter taste, and low centrifugal sedimentation rate. This indicates that the citrus beverage prepared using the raw materials and method described in this application has excellent flavor, nutritional and health value, and stability.

[0076] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A preparation process for a citrus beverage based on probiotic fermentation, characterized in that: The following steps are involved: S1, pretreatment of raw juice to obtain fermentation bottom liquid; S2, vaccination; S3, fermentation to obtain fermentation liquid; S4, post-processing; In step S1, the specific steps of pre-treating the raw juice are: squeezing the citrus juice, sieving to obtain the citrus juice, adding the enzyme preparation for enzymatic hydrolysis, adding the sugar source, stirring evenly, adjusting the pH, pasteurizing, and cooling; The enzyme preparation comprises naringinase, beta-glucosidase, cellulase and neutral protease.

2. The preparation process of the probiotic fermented citrus beverage according to claim 1, characterized in that: The added amount of the enzyme preparation is 130-200 U / mL citrus juice.

3. The preparation process of the probiotic fermented citrus beverage according to claim 2, characterized in that: The ratio of the added amounts of naringinase, β-glucosidase, cellulase and neutral protease is (3-5): (1-3): (1-2):

1.

4. The preparation process of the probiotic fermented citrus beverage according to claim 3, characterized in that: The specific steps of the enzymatic hydrolysis are: first adding naringinase, β-glucosidase and cellulase, carrying out enzymatic hydrolysis for 1-2 hours at a pH of 4.0 and a temperature of 40-50° C., stirring at a speed of 40-60 rpm, then adjusting the pH to 6.5-7.5, keeping the temperature and stirring speed unchanged, and carrying out enzymatic hydrolysis for 45-60 minutes.

5. The preparation process of the probiotic fermented citrus beverage according to claim 1, characterized in that: In step S2, the specific step of inoculation is: inoculating the composite probiotic starter into the fermentation base liquid.

6. The process for preparing a probiotic fermented citrus beverage according to claim 5, characterized in that: The composite probiotic fermentation agent comprises Lactobacillus plantarum, Lactobacillus rhamnosus and Lactobacillus acidophilus.

7. The process for preparing a probiotic fermented citrus beverage according to claim 6, characterized in that: The inoculation amount of the composite probiotic fermentation agent is 1×10 7 -5×10 7 CFU / mL fermentation base liquid.

8. The process for preparing a probiotic fermented citrus beverage according to claim 7, characterized in that: The inoculation ratio of Lactobacillus plantarum, Lactobacillus rhamnosus and Lactobacillus acidophilus is (4-6): (3-5):

1.

9. The process for preparing a probiotic fermented citrus beverage according to claim 8, characterized in that: In step S3, the fermentation is a two-stage temperature-controlled fermentation, and the specific fermentation steps are: in the first stage, microaerobic fermentation is performed at 30-32°C for 18-24 hours. When the pH drops to 3.8-4.2, oligofructose is added, the temperature is lowered to 20-25°C, and the second stage is entered, anaerobic fermentation is performed at 20-25°C for 12-24 hours, and the temperature is rapidly cooled to 4-10°C to terminate the fermentation.

10. A citrus beverage prepared according to the process for preparing a citrus beverage based on probiotic fermentation according to any one of claims 1 to 9.