Method for synergistically fermenting ginseng powder by bacteria and enzyme, acetobacter fruit, ginseng spice and application

Abstract

The present application belongs to the field of microorganism and fermentation technology, and discloses a method for synergistically fermenting ginseng powder by bacteria and enzymes, and fructobacillus, ginseng spice and application. The method comprises the following steps: (1) preparing ginseng powder liquid medium; (2) inoculating fructobacillus and cellulase, and liquid fermentation for 24-36 hours; (3) inoculating amylase, and continuing fermentation for 96-120 hours; (4) after the fermentation is completed, supplementing ethanol to a final volume concentration of 45%-55%, stirring at room temperature for 24 hours, standing and settling, and filtering to obtain supernatant, which is ginseng spice. Through the synergistic fermentation of bacteria and enzymes and the specific microbial fermentation metabolism control technology, the ginseng spice obtained by the present application can significantly reduce the earthy smell of traditional ginseng spice, has typical aroma characteristics, has strong absorbability, and effectively improves the product quality of ginseng spice series cigarettes.

Description

Technical Field

[0001] This invention belongs to the field of microbiology and fermentation technology, and in particular to a method for synergistic fermentation of ginseng powder by bacteria and enzymes, as well as the fruit acetobacterium, ginseng flavoring, and their applications. Background Technology

[0002] Product flavor is a key indicator for evaluating quality. The presence of off-odors can severely reduce product quality, directly affecting consumers' sensory evaluation and causing significant economic losses to businesses. Typically, compounds that cause off-odors exist in low concentrations but produce a strong smell; therefore, these "small in quantity, large in aroma" compounds directly impact product quality.

[0003] Ginseng-flavored cigarettes are made with ginseng and other spices, resulting in a rich aroma, lingering fragrance, unique formula, and high-quality ingredients. Each puff fills the room with fragrance, making them very popular. However, most ginseng spices are extracted directly from ginseng using various methods, often resulting in a slightly earthy or off-odor that negatively impacts product quality.

[0004] To further enhance the development and application of ginseng flavoring, after a thorough study of the off-odor characteristics of the existing ginseng flavoring's "earthy" aroma, octadecyl vinyl ether (CDE) was identified as the key off-odor compound. Furthermore, targeting the metabolic characteristics of CDE, the global metabolic pathway was obtained using the KEGG database, identifying the dominant microorganisms and key enzyme systems that can influence its synthesis and metabolism. Simultaneously, using metabolic flux models and microbial resource databases, a synergistic microbial-enzyme system was determined that can effectively reduce CDE content and increase volatile flavor compounds. Finally, using microbial directed synthesis and metabolic control technology, ginseng fermented flavoring was prepared and applied to cigarettes to improve product quality and highlight its unique style. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for synergistic fermentation of ginseng powder by bacteria and enzymes, as well as the fruit acetobacterium, ginseng flavoring, and their applications.

[0006] The technical solution adopted by this invention to solve its technical problem is:

[0007] A strain of Acetobacter fruitii that can ferment ginseng powder through synergistic fermentation of bacteria and enzymes ( Acetobacter pomorum The name of the *Acetobacter fructus* is AAF20190930-9, its classification name is *Acetobacter fructus*, its accession number is CGMCCNo.18664, its accession date is October 11, 2019, and its depository institution is the China General Microbiological Culture Collection Center, No. 3, No. 1, Beichen West Road, Chaoyang District, Beijing.

[0008] The method of co-fermenting ginseng powder using Acetobacter fructus as described above, wherein cellulase, amylase and Acetobacter fructus are co-fermented.

[0009] Furthermore, it includes the following steps:

[0010] (1) Prepare a liquid culture medium for ginseng powder with 2%-10% ginseng powder, 0.5% glucose and 0.05%-0.1% potassium chloride and adjust the pH value to 4.5-5.0. Sterilize by autoclaving at 115℃ for 30 min. The percentages mentioned above are final mass concentrations and the solvent is water.

[0011] (2) First stage fermentation: After the ginseng powder liquid culture medium is sterilized, acetic acid bacteria and cellulase are inoculated and liquid fermentation is carried out for 24-36 hours;

[0012] (3) Second stage fermentation: After fermentation for 24-36 hours, amylase is added and fermentation continues for 96-120 hours;

[0013] (4) After fermentation, add ethanol to a final volume concentration of 45%-55%, stir at room temperature for 24 hours, let stand to settle and filter to obtain the supernatant, which is ginseng flavoring.

[0014] Furthermore, in steps (2) and (3), based on the total weight of the ginseng powder liquid culture medium, the amount of *Acetobacter fructus* added is 0.5-1% of the total weight of the ginseng powder liquid culture medium, and the viable count of the *Acetobacter fructus* inoculant is (1-8) × (10^6)^2. 8 ~10 9 The dosage of cellulase is 8000-10000 U / kg; the dosage of amylase is 1000-5000 U / kg.

[0015] Furthermore, in step (2), the fermentation conditions are: fermentation temperature 28-32℃, stirring during fermentation, stirring speed 50-100 rpm, and aeration rate 50-70 L / h.

[0016] Furthermore, in step (3), the fermentation conditions are: fermentation temperature 33-35℃, stirring during fermentation, stirring speed 120-150 rpm, and aeration rate 120-150 L / h.

[0017] The ginseng flavoring was prepared using the method described above.

[0018] Furthermore, the content of octadecyl vinyl ether in the ginseng flavoring can be reduced by more than 80%.

[0019] The application of ginseng flavoring in cigarette production as described above.

[0020] Furthermore, adding ginseng flavoring to cigarette products can significantly reduce the earthy taste in the combustion smoke.

[0021] The advantages and positive effects of this invention are as follows:

[0022] 1. The bacterial-enzyme synergistic technology of this invention relies on the metabolic characteristics of octadecyl vinyl ether. It uses the KEGG database to obtain the global metabolic pathway, identifies the dominant microorganisms and their key enzyme systems that can affect its synergistic metabolism, and determines the minimum scale of colony metabolic pathways through pathway splicing and other methods. Furthermore, it uses metabolic flux models and microbial resource databases to obtain candidate microorganisms and key enzyme systems, and determines the optimal bacterial-enzyme synergistic system through database mining, high-throughput screening and other methods.

[0023] 2. The Acetobacter flavum strain AAF20190930-9 selected in this invention has undergone multiple rounds of screening and evaluation. The combination of this strain with cellulase and amylase, and through specific fermentation metabolism control technology, achieves the most efficient bacterial-enzyme synergistic fermentation technology, which can minimize the content of octadecyl vinyl ether and increase the content of volatile flavor substances.

[0024] 3. The fermentation metabolism control technology in the method of this invention is optimized based on the clear understanding of the synergistic metabolic network and interaction mechanism of cellulase, amylase and Acetobacter fructus CGMCC No.18664. KEGG enrichment analysis revealed that their synergistic metabolic pathways are mainly the tricarboxylic acid cycle, β-alanine metabolism and tyrosine metabolism.

[0025] 4. The method of this invention uses cellulase and amylase as the core enzyme system, and simultaneously inoculates *Acetobacter flavum* into the ginseng powder culture medium. Liquid fermentation is carried out through fermentation metabolism control and other methods. After fermentation is terminated, ginseng flavoring is prepared. This invention, through synergistic microbial-enzyme interaction and specific microbial fermentation metabolism control technologies, obtains ginseng flavoring that significantly reduces the earthy taste of traditional ginseng flavoring while retaining typical aroma characteristics and strong smokeability, effectively improving the product quality of ginseng flavored cigarettes. Attached Figure Description

[0026] Figure 1 This is a colony morphology diagram of Acetobacter fructus AAF20190930-9 in this invention;

[0027] The name of *Acetobacter flavus* in this invention is: AAF20190930-9, the classification name is: *Acetobacter flavus*, the accession number is: CGMCC No.18664, the accession date is: October 11, 2019, and the depository is: China General Microbiological Culture Collection Center, No.3, No.1 Beichen West Road, Chaoyang District, Beijing. Detailed Implementation

[0028] The present invention will be further described below with reference to the embodiments. The following embodiments are descriptive and not limiting, and should not be used to limit the scope of protection of the present invention.

[0029] The various experimental operations involved in the specific embodiments are all conventional techniques in the art. For parts not specifically annotated herein, those skilled in the art can refer to various commonly used reference books, scientific and technological literature, or related instructions and manuals prior to the filing date of this invention for implementation. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art, and the raw materials used are all commercially available products.

[0030] A strain of Acetobacter fruitii that can ferment ginseng powder through synergistic fermentation of bacteria and enzymes ( Acetobacter pomorum The name of the *Acetobacter fructus* is AAF20190930-9, its classification name is *Acetobacter fructus*, its accession number is CGMCCNo.18664, its accession date is October 11, 2019, and its depository institution is the China General Microbiological Culture Collection Center, No. 3, No. 1, Beichen West Road, Chaoyang District, Beijing.

[0031] The method of co-fermenting ginseng powder using Acetobacter fructus as described above, wherein cellulase, amylase and Acetobacter fructus are co-fermented.

[0032] Preferably, the steps include:

[0033] (1) Prepare a liquid culture medium for ginseng powder with 2%-10% ginseng powder, 0.5% glucose and 0.05%-0.1% potassium chloride and adjust the pH value to 4.5-5.0. Sterilize by autoclaving at 115℃ for 30 min. The percentages mentioned above are final mass concentrations and the solvent is water.

[0034] (2) First stage fermentation: After the ginseng powder liquid culture medium is sterilized, acetic acid bacteria and cellulase are inoculated and liquid fermentation is carried out for 24-36 hours;

[0035] (3) Second stage fermentation: After fermentation for 24-36 hours, amylase is added and fermentation continues for 96-120 hours;

[0036] (4) After fermentation, add ethanol to a final volume concentration of 45%-55%, stir at room temperature for 24 hours, let stand to settle and filter to obtain the supernatant, which is ginseng flavoring.

[0037] Preferably, in steps (2) and (3), the amount of *Acetobacter fructus* added is 0.5-1% of the total weight of the ginseng powder liquid culture medium, and the viable count of the *Acetobacter fructus* inoculant is (1-8) × (10^6)^6. 8 ~10 9 The dosage of cellulase is 8000-10000 U / kg; the dosage of amylase is 1000-5000 U / kg.

[0038] Preferably, in step (2), the fermentation conditions are: fermentation temperature 28-32℃, stirring during fermentation, stirring speed 50-100 rpm, and aeration rate 50-70 L / h.

[0039] Preferably, in step (3), the fermentation conditions are: fermentation temperature 33-35℃, stirring during fermentation, stirring speed 120-150 rpm, and aeration rate 120-150 L / h.

[0040] The ginseng flavoring was prepared using the method described above.

[0041] Preferably, the content of octadecyl vinyl ether in the ginseng flavoring can be reduced by more than 80%.

[0042] The application of ginseng flavoring in cigarette production as described above.

[0043] Preferably, adding ginseng flavoring to cigarette products can significantly reduce the earthy taste in the combustion smoke.

[0044] Specifically, the relevant preparation and testing methods are as follows:

[0045] A strain of Acetobacter fruitii that can ferment ginseng powder through synergistic fermentation of bacteria and enzymes ( Acetobacter pomorum The name of the *Acetobacter fructus* is AAF20190930-9, its classification name is *Acetobacter fructus*, its accession number is CGMCCNo.18664, its accession date is October 25, 2019, and its depository institution is the China General Microbiological Culture Collection Center, No. 3, No. 1, Beichen West Road, Chaoyang District, Beijing.

[0046] The relevant screening method for the fruit acetobacterium AAF20190930-9 is as follows:

[0047] Sample source: vinegar mash, collected from the acetic acid fermentation workshop of Shanxi Zilin Vinegar Industry Co., Ltd.

[0048] The culture medium used is:

[0049] Glucose-yeast extract solid culture medium: 10g glucose, 10g yeast extract, 15g calcium carbonate, 1000mL distilled water, 2.0 g / L agar. Sterilize at 121℃ for 30min.

[0050] Glucose-yeast extract liquid culture medium: 10g glucose, 10g yeast extract, 15g calcium carbonate, 20ml anhydrous ethanol, 1000mL distilled water. Sterilize at 121℃ for 30min.

[0051] The vinegar mash was rinsed with 0.9% sterile saline solution to prepare a dilution of 10. -1 The mother liquor was serially diluted using the 10-fold dilution method to obtain a dilution factor of 10. -2 ~10 -5 200 μL of the bacterial suspension was spread onto glucose yeast extract solid medium for culture. The appropriate dilution was selected based on the number of colonies grown on the medium. 100 μL of the sample solution was then plated on glucose yeast extract solid medium and incubated at 30°C for 24 h. Colonies were picked and streaked repeatedly until single colonies appeared. The cells were then inoculated into 5 mL of fresh glucose yeast extract liquid medium and cultured under the following conditions: 30°C at 180 r / min for 24 h. The resulting bacterial suspension was then subcultured for one generation at a 2% inoculum as the seed culture for subsequent experiments.

[0052] Its colony morphology diagram is as follows Figure 1 As shown, from Figure 1 As can be seen, the colony is round, with rough edges, opaque, milky white, moist, and easy to pick up.

[0053] Example 1

[0054] The method for preparing ginseng flavoring by co-fermenting ginseng powder with the enzymes of Acetobacter fruit as described above includes the following steps:

[0055] Prepare 3500 mL of liquid culture medium with 5% ginseng powder, 0.5% glucose, and 0.05% potassium chloride, and adjust the pH to 5.0. Autoclave at 115℃ for 30 min. All percentages are final mass concentrations, and water is the solvent. After sterilization, inoculate with 24 g of *Acetobacter flavus* AAF20190930-9 (5 × 10⁻⁶ viable cells). 8The ginseng was fermented with 36,000 U of cellulase (cFu / g) at 30°C, with a stirring speed of 80 rpm and an aeration rate of 50 L / h for 36 hours. After fermentation, 10,000 U of amylase was added, and the fermentation conditions were adjusted to 35°C, 150 rpm, and 150 L / h for 120 hours. After fermentation was terminated, anhydrous ethanol was added to bring the final ethanol concentration to 50%, and the mixture was stirred at room temperature for 24 hours. The mixture was allowed to settle and then filtered to obtain the supernatant, which is the ginseng flavoring.

[0056] Comparative Example 1

[0057] This comparative example was inoculated with another strain of Acetobacter flavum CICC 24175 (purchased from the China Industrial Microbial Culture Collection Center), and other conditions were the same as in Example 1.

[0058] The specific steps are as follows: Prepare 3500 mL of liquid culture medium with 5% ginseng powder, 0.5% glucose, and 0.05% potassium chloride, and adjust the pH to 5.0. Autoclave at 115℃ for 30 min; all percentages mentioned above are final mass concentrations, and the solvent is water; after sterilization, inoculate with 24 g of Acetobacter fruit bacteria agent (5 × 10⁻⁶ viable cells). 8 The ginseng was fermented with 36,000 U of cellulase (cFu / g) at 30°C, with a stirring speed of 80 rpm and an aeration rate of 50 L / h for 36 hours. After fermentation, 10,000 U of amylase was added, and the fermentation conditions were adjusted to 35°C, 150 rpm, and 150 L / h for 120 hours. After fermentation was terminated, anhydrous ethanol was added to bring the final ethanol concentration to 50%, and the mixture was stirred at room temperature for 24 hours. The mixture was allowed to settle and then filtered to obtain the supernatant, which is the ginseng flavoring.

[0059] Comparative Example 2

[0060] This comparative example was not inoculated with Acetobacter flavum, and all other conditions were the same as in Example 1.

[0061] The specific steps are as follows: Prepare 3500 mL of liquid culture medium with 5% ginseng powder, 0.5% glucose, and 0.05% potassium chloride, and adjust the pH to 5.0. Autoclave at 115℃ for 30 min. All percentages are final mass concentrations, and the solvent is water. After sterilization, add 36000 U of cellulase, ferment at 30℃, stir at 80 rpm, and aerate at 50 L / h. After 36 h of liquid fermentation, add 10000 U of amylase and adjust the fermentation conditions to 35℃, 150 rpm, and 150 L / h. Continue fermentation for 120 h. After fermentation is terminated, add anhydrous ethanol to a final ethanol volume concentration of 50%, stir at room temperature for 24 h, allow to settle, and filter to obtain the supernatant, which is the ginseng flavoring.

[0062] Comparative Example 3

[0063] This comparative example did not include cellulase, and all other conditions were the same as in Example 1.

[0064] The specific steps are as follows: Prepare 3500 mL of liquid culture medium with 5% ginseng powder, 0.5% glucose, and 0.05% potassium chloride, and adjust the pH to 5.0. Autoclave at 115℃ for 30 min. All percentages are final mass concentrations, and the solvent is water. After sterilization, inoculate with 24 g of *Acetobacter flavus* AAF20190930-9 bacterial agent (5 × 10⁻⁶ viable cells). 8 The fermentation conditions were as follows: fermentation temperature 30℃, stirring speed 80 rpm, aeration rate 50 L / h. After 36 hours of liquid fermentation, 10000 U of amylase was added, and the fermentation conditions were adjusted to fermentation temperature 35℃, stirring speed 150 rpm, aeration rate 150 L / h, and fermentation continued for 120 hours. After fermentation was terminated, anhydrous ethanol was added to bring the final ethanol concentration to 50%, and the mixture was stirred at room temperature for 24 hours. After settling and filtration, the supernatant was obtained, which is the ginseng flavoring.

[0065] Comparative Example 4

[0066] This comparative example did not include amylase, and all other conditions were the same as in Example 1.

[0067] The specific steps are as follows: Prepare 3500 mL of liquid culture medium with 5% ginseng powder, 0.5% glucose, and 0.05% potassium chloride, and adjust the pH to 5.0. Autoclave at 115℃ for 30 min. All percentages are final mass concentrations, and the solvent is water. After sterilization, inoculate with 24 g of *Acetobacter flavus* AAF20190930-9 bacterial agent (5 × 10⁻⁶ viable cells). 8 The ginseng was fermented with 36,000 U of cellulase (cFu / g) at 30°C, with a stirring speed of 80 rpm and an aeration rate of 50 L / h for 36 hours. After fermentation, the conditions were adjusted to 35°C, 150 rpm, and 150 L / h, and fermentation continued for another 120 hours. After fermentation was terminated, anhydrous ethanol was added to bring the final ethanol concentration to 50%, and the mixture was stirred at room temperature for 24 hours. The mixture was allowed to settle and then filtered to obtain the supernatant, which was the ginseng flavoring.

[0068] Comparative Example 5

[0069] In this comparative example, after adding amylase, the fermentation conditions were not adjusted, and other conditions were the same as in Example 1.

[0070] The specific steps are as follows: Prepare 3500 mL of liquid culture medium with 5% ginseng powder, 0.5% glucose, and 0.05% potassium chloride, and adjust the pH to 5.0. Autoclave at 115℃ for 30 min. All percentages are final mass concentrations, and the solvent is water. After sterilization, inoculate with 24 g of *Acetobacter flavus* AAF20190930-9 bacterial agent (5 × 10⁻⁶ viable cells). 8 The mixture was prepared with 36,000 U of cellulase (cFu / g), fermented at 30°C, stirred at 80 rpm, and aerated at 50 L / h. After 36 hours of liquid fermentation, 10,000 U of amylase was added, and fermentation continued for another 120 hours. After fermentation was terminated, anhydrous ethanol was added to bring the final ethanol concentration to 50%. The mixture was stirred at room temperature for 24 hours, allowed to settle, and filtered to obtain the supernatant, which is the ginseng flavoring.

[0071] Comparative Example 6

[0072] This comparative example was not inoculated with bacterial enzymes and did not ferment; other conditions were the same as in Example 1.

[0073] The specific steps are as follows: Prepare 3500 mL of liquid culture medium with 5% ginseng powder, 0.5% glucose, and 0.05% potassium chloride, and adjust the pH value to 5.0. Autoclave at 115℃ for 30 min. All percentages mentioned above are final mass concentrations, and the solvent is water. After standing at room temperature for 156 h, add anhydrous ethanol to a final ethanol volume concentration of 50%, stir at room temperature for 24 h, let stand to settle, and filter to obtain the supernatant, which is the ginseng flavoring.

[0074] Effect evaluation:

[0075] This invention provides a method for fermenting ginseng powder using a synergistic fermentation technique to reduce the earthy odor of ginseng flavoring, and a fruit acetobacterium. To demonstrate its effectiveness, the research results are as follows:

[0076] Qualitative and quantitative analysis of octadecyl vinyl ether in ginseng flavoring was performed using headspace solid-phase microextraction (HS-SPME) combined with two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS). GC×GC-TOF-MS data were obtained from LECO Chroma TOF. The workstation performs data processing, automatically integrating, deconvolving, and comparing the chromatographic peaks with NIST 14 and Wiley 9 mass spectrometry libraries to generate a "peak table". Compounds with both forward and reverse similarities >800 are selected from the "peak table". Retention indices (RIs) are obtained by calibration using straight-chain n-alkane (C7-C30) standard solutions under the same temperature program. Compounds with retention indices >50 compared to those recorded in the literature (Sun Huifan, Wu Shengwen, Lin Pei, et al. Analysis of three special-aroma baijiu flavor compounds based on GC×GC-TOF MS technology [J]. China Brewing, 2025, 44 (08): 277-285.) are removed. Octadecyl vinyl ether is quantitatively analyzed using the internal standard method and standard curve.

[0077] Furthermore, at an addition rate of 1 / 1000, the ginseng flavoring prepared in the examples and comparative examples was injected into the finished cigarette using a syringe. Sensory quantitative descriptive analysis was used to evaluate and score the finished cigarette containing the ginseng flavoring. The sensory evaluation team consisted of 10 evaluators, including 5 men and 5 women, aged 23-26 years, each of whom had undergone 3 months of training. Samples were randomly numbered and presented. Evaluators scored the aroma based on the intensity of the earthy scent, ranging from 0 to 5 points, where 0 points represent no perceptibility, 1 point represents weak aroma, 2 points represent identifiable aroma, 3 points represent strong aroma, 4 points represent prominent aroma, and 5 points represent extremely strong aroma, with a minimum score difference of 0.5. The sensory evaluation was conducted in a sensory evaluation room at 25°C, and the experiment was repeated three times. The final score was the average.

[0078] The results of the content detection and sensory evaluation of octadecyl vinyl ether in the examples and comparative examples are shown in Table 1. Comparative Example 6, prepared by conventional extraction method, had the highest octadecyl vinyl ether content and earthy smell score. The ginseng flavoring in the examples was prepared under optimal conditions obtained after extensive data mining, high-throughput screening, and screening of superior strains. Its octadecyl vinyl ether content was much lower than that of Comparative Example 6, less than 15% of that in Comparative Example 6. That is, the ginseng flavoring prepared by the method described in this invention can significantly reduce the earthy smell characteristic compounds by more than 80%. In addition, in terms of earthy smell sensory scoring, the ginseng flavoring in the examples had the weakest earthy smell. Specifically, compared with the comparative examples, Example 1 had the lowest octadecyl vinyl ether content. Compared with Comparative Examples 1-6, its octadecyl vinyl ether content was 31%, 16%, 19%, 18%, 21%, and 13%, respectively. Meanwhile, comparing the earthy smell scores of Example 1 with the comparative examples, Example 1 had the lowest score. Compared with Comparative Examples 1-6, its earthy smell scores were 56%, 24%, 27%, 25%, 28%, and 21%, respectively.

[0079] Compared with Example 1, Comparative Example 1 (inoculated with another Acetobacter fructus CICC 24175) showed significant differences in octadecyl vinyl ether content and earthy odor score. Furthermore, Comparative Example 1 (inoculated with another Acetobacter fructus CICC 24175) also showed the lowest octadecyl vinyl ether content and earthy odor score compared to other comparative examples, indicating the important role of Acetobacter fructus in the ginseng powder fermentation process, especially the Acetobacter fructus CGMCC No. 18664 described in this patent, which exhibits the best effect.

[0080] Secondly, compared with Comparative Example 6 (which was not inoculated with bacterial enzymes and did not ferment), Comparative Examples 2-5 showed certain differences in their octadecyl vinyl ether content and earthy smell score, indicating that each key preparation step described in this patent has a positive effect on the octadecyl vinyl ether content and earthy smell score.

[0081] Table 1. Content detection and off-odor scoring results

[0082]

[0083] Meanwhile, by comparing Example 1, Comparative Example 2, and Comparative Example 3, it can be seen that the *Acetobacter fructus* AAF20190930-9 inoculum and cellulase in the method of the present invention have a synergistic effect, which can synergistically improve the relevant properties of the prepared ginseng flavoring. In particular, in the method of the present invention, 24g of *Acetobacter fructus* inoculum (viable count 5 × 10⁻⁶) is added to 3500mL of liquid culture medium. 8 The cFu / g and 36000U cellulase have a significant synergistic effect, which can significantly improve the relevant properties of the prepared ginseng flavoring.

[0084] Meanwhile, by comparing Examples 1, 3, and 4, it can be seen that the amylase and cellulase in the method of the present invention have a synergistic effect, which can synergistically improve the relevant properties of the prepared ginseng flavoring. In particular, the cellulase and amylase in the ratio of 36000U:10000U in the method of the present invention have a significant synergistic effect, which can significantly synergistically improve the relevant properties of the prepared ginseng flavoring.

[0085] In summary, the method and Acetobacter fruit strain of the present invention, which uses a synergistic fermentation technique to ferment ginseng powder to reduce the earthy odor of ginseng flavoring, have good application effects. They can significantly reduce the content of octadecyl vinyl ether, a characteristic compound of earthy odor in ginseng flavoring, and reduce the earthy odor in ginseng series cigarette products.

[0086] Although embodiments of the invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations, and modifications are possible without departing from the spirit and scope of the invention and the appended claims. Therefore, the scope of the invention is not limited to the contents disclosed in the embodiments.

Claims

1. A strain of Acetobacter fruitii capable of fermenting ginseng powder through synergistic fermentation of bacteria and enzymes ( Acetobacter pomorum ), characterized by: The name of the Acetobacter fructus is AAF20190930-9, the classification name is Acetobacter fructus, the accession number is CGMCC No.18664, the accession date is October 11, 2019, and the depository is China General Microbiological Culture Collection Center, No.3, No.1 Beichen West Road, Chaoyang District, Beijing.

2. The method for co-fermenting ginseng powder using *Acetobacter flavum* and its enzymes as described in claim 1, characterized in that: The method employs synergistic fermentation of cellulase, amylase, and acetic acid bacteria.

3. The method according to claim 2, characterized in that: Includes the following steps: (1) Prepare a liquid culture medium for ginseng powder with 2%-10% ginseng powder, 0.5% glucose and 0.05%-0.1% potassium chloride and adjust the pH value to 4.5-5.

0. Sterilize by autoclaving at 115℃ for 30 min. The percentages mentioned above are final mass concentrations and the solvent is water. (2) First stage fermentation: After the ginseng powder liquid culture medium is sterilized, acetic acid bacteria and cellulase are inoculated and liquid fermentation is carried out for 24-36 hours; (3) Second stage fermentation: After fermentation for 24-36 hours, amylase is added and fermentation continues for 96-120 hours; (4) After fermentation, add ethanol to a final volume concentration of 45%-55%, stir at room temperature for 24 hours, let stand to settle and filter to obtain the supernatant, which is ginseng flavoring.

4. The method according to claim 3, characterized in that: In steps (2) and (3), the amount of Acetobacter fructus added is 0.5-1% of the total weight of the ginseng powder liquid culture medium, and the viable count of Acetobacter fructus is (1-8) × (10^6)^6. 8 ~10 9 The dosage of cellulase is 8000-10000 U / kg; the dosage of amylase is 1000-5000 U / kg.

5. The method according to claim 3, characterized in that: In step (2), the fermentation conditions are: fermentation temperature 28-32℃, stirring during fermentation, stirring speed 50-100 rpm, and aeration rate 50-70 L / h.

6. The method according to any one of claims 3 to 5, characterized in that: In step (3), the fermentation conditions are: fermentation temperature 33-35℃, stirring during fermentation, stirring speed 120-150 rpm, and aeration rate 120-150 L / h.

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