Staphylococcus terrae with high temperature resistance and its application

Abstract

The application discloses a soil staphylococcus with high-temperature resistance and smoking resistance, and application thereof, and belongs to the technical field of microbial application and fermented meat products. The soil staphylococcus has a preservation number of CGMCC No. 34994, is named XUCSB 058, has nitrate reductase, catalase, proteolytic enzyme and lipolytic enzyme, can produce acid by utilizing glucose, and has the characteristics of acid resistance, salt resistance, nitrite resistance, low-temperature resistance, non-hemolysis, non-stick production, non-gas production, non-biogenic amine production, non-NH3 production, non-H2S production and the like. The soil staphylococcus has the characteristics of high-temperature resistance and smoking resistance, can promote the persistent formation of color and flavor of smoking fermented meat (such as bacon, sausage, smoked ham and the like), and has the potential of being safely used in the production of various smoking fermented meat (such as bacon, sausage, smoked ham and the like).

Description

Technical Field

[0001] This invention belongs to the field of microbial application and fermented meat product technology, specifically relating to a strain of Staphylococcus aureus with resistance to smoke and high temperatures and its application. Background Technology

[0002] Fermented meat products are popular with consumers due to their long shelf life, unique taste, and rich nutrition. Traditional fermented meat products rely on natural fermentation by local microorganisms without the addition of starter cultures, making them highly susceptible to contamination by other microorganisms, which can spoil the final product and even produce harmful substances that endanger human health. The use of local starter cultures helps standardize product characteristics, improve the safety and stability of fermented meat, inhibit spoilage and harm caused by harmful microorganisms, shorten production cycles, enrich product flavor, and preserve original and specific sensory qualities.

[0003] Smoked bacon and sausages are traditional Chinese fermented meat products with a history of thousands of years, especially in the southern regions of China, where they are favored by many consumers for their rich smoky flavor, aroma, texture, and taste. The smoking process, which involves the incomplete combustion of materials such as wood, sawdust, and tea leaves, is used to enhance the flavor, color, and aroma of fermented meats. The smoking temperature for traditionally smoked fermented meats varies significantly depending on the local processing methods. For example, Sichuan bacon is typically smoked at 40-55℃, while Hunan bacon is typically smoked at 50-70℃. The smoking temperature can also be manually adjusted according to different processing requirements, such as long-term cold smoking at 12-25℃, short-term warm smoking at 25-45℃, and short-term hot smoking at 45-70℃. However, the starter cultures are easily deactivated or killed under the high temperatures of smoking, leading to interruption of fermentation in cured meats or sausages, insufficient flavor development, and inconsistent product batches, severely restricting the development of smoked and fermented meats. Therefore, the development and industrialization of high-temperature resistant fermentation cultures for meat products with local smoked flavor characteristics are crucial for ensuring people's health and food safety, and for promoting the improvement of the quality and efficiency of smoked meat products in my country.

[0004] Invention patent CN 119570693 A describes a strain of Staphylococcus aureus H3 and its applications. This strain promotes color development in meat product fermentation without the addition of nitrite. Strain H3 also exhibits strong antioxidant properties, inhibits lipid oxidation, and produces polysaccharides with antioxidant effects, contributing to the maintenance of meat color. When sausages were fermented with strain H3, the nitrite content was significantly reduced, and the sausage's firmness, cohesiveness, elasticity, and chewiness were improved, resulting in a richer flavor and enhanced umami. However, the application of this Staphylococcus aureus H3 in smoked meat products, especially its suitability for hot smoking processes, has not been described. Furthermore, strains with high-temperature resistance to smoking are rarely reported. Summary of the Invention

[0005] The technical problem to be solved by this invention is how to provide a strain of Staphylococcus aureus with resistance to smoke and high temperatures and its application.

[0006] The present invention solves the above-mentioned technical problems through the following technical means:

[0007] The first aspect of this invention provides a strain of Staphylococcus aureus that is resistant to smoke and high temperatures. Staphylococcus edaphicus XUCSB 058, accession number CGMCCNo.34994.

[0008] Preferably, the 16S rDNA sequence of this strain is shown in SEQ ID NO. 1.

[0009] A second aspect of the present invention proposes the application of the above-mentioned Staphylococcus aureus XUCSB 058 in the fermentation preparation of meat products.

[0010] The present invention also proposes the application of the above-mentioned Staphylococcus aureus XUCSB 058 in the preparation of meat fermentation inoculants.

[0011] A third aspect of the present invention provides a meat fermentation agent with resistance to high temperatures from smoking, the main components of which include one or more of the above-mentioned Staphylococcus aureus XUCSB 058, its bacterial suspension or fermentation broth.

[0012] The fourth aspect of the present invention provides a method for improving the flavor quality of smoked meat fermented products, comprising the following steps: adding the above-mentioned meat fermentation agent during the preparation of smoked meat fermented products.

[0013] Preferably, the meat includes, but is not limited to, pork, beef, mutton, or its heart, liver, lungs, kidneys, etc.

[0014] Preferably, the fermented meat products include, but are not limited to, cured meat, sausage, ham, and sausage.

[0015] Preferably, the main component of the meat fermentation inoculant is *Staphylococcus aureus* XUCSB 058, and the concentration of *Staphylococcus aureus* XUCSB 058 in the meat fermentation inoculant is 1.5~2.5×10⁻⁶. 7 CFU / g.

[0016] Preferably, the process includes the following steps: cutting the meat into long strips, adding ingredients and meat fermentation agents, and semi-dry marinating; then hanging it in a pre-sterilized constant temperature and humidity chamber for fermentation; then taking it out and hanging it for smoking.

[0017] Preferably, the ingredients include salt, sodium nitrite, Sichuan pepper, white sugar, and white wine.

[0018] Preferably, the fermentation process is as follows: fermentation at 10~20℃ for 4~8 days, with a relative humidity of 50~70%.

[0019] Preferably, the fumigation conditions are: 40~50℃, 4~8h.

[0020] Preferably, the method includes the following steps: cutting the meat into long strips, adding 2.0-3.0% salt, 0.005-0.02% sodium nitrite, 0.2-0.6% Sichuan peppercorns, 0.5-2.0% white sugar, and 0.1-0.2% white wine by weight; and adding Staphylococcus aureus XUCSB058 to a concentration of 1.5-2.5 × 10⁻⁶. 7 CFU / g; semi-dry pickling at 3~5℃ for 0.5~1.5 days; then hanging in a pre-sterilized constant temperature and humidity chamber for fermentation; fermentation program: fermentation at 10~20℃ for 4~8 days, relative humidity 50~70%; then take it out, hang it at 40~50℃ for smoking for 4~8 hours, hang it in a ventilated place to dissipate heat for 4~8 hours; finally, store at 10℃ for 1~3 days to allow its flavor to mature.

[0021] The beneficial effects of this invention are as follows: 1. This invention provides a native fermentation agent, Staphylococcus aureus XUCSB 058 ( Staphylococcus edaphicus XUCSB 058) is beneficial for the rapid development of fermented meat products with smoky flavor, improving the problem of fermentation interruption caused by high-temperature smoking, and enhancing product uniformity, stability, and safety.

[0022] 2. This invention screened a strain of Staphylococcus aureus XUCSB 058 with excellent fermentation characteristics from cured pork from Changsha, Hunan. Staphylococcus edaphicusThe strain XUCSB 058, deposited at the China General Microbiological Culture Collection Center (CGMCC, deposit date June 24, 2025, accession number CGMCCNo. 34994, address: No. 3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing), is a *Staphylococcus aureus* strain. This invention provides a strain of *Staphylococcus aureus* XUCSB 058 that possesses nitrate reductase, catalase, proteolytic enzymes, and lipolytic enzymes. It can utilize glucose to produce acid and exhibits acid resistance, salt resistance, nitrite resistance, low-temperature resistance, non-hemolysis, non-viscosity, non-gas production, non-producing of biogenic amines, non-producing NH3, and non-producing H2S. It is sensitive to eight common antibiotics, including rifampin, chloramphenicol, kanamycin, streptomycin, tetracycline, penicillin, vancomycin, and gentamicin, and no enterotoxin genes or biogenic amine genes were detected. Among them, Staphylococcus aureus XUCSB 058 exhibits high-temperature resistance to smoking, which can promote the sustained formation of color and flavor characteristics in smoked and fermented meat. These characteristics indicate that this strain has the potential to be safely used in the production of various smoked and fermented meats (such as bacon, sausage, and smoked ham).

[0023] 3. Breaking through the bottlenecks of traditional high-temperature smoking processes, achieving a balance between continuous fermentation and stable quality. Traditional fermented meat products often suffer from inactivation of starter cultures due to high temperatures during the smoking stage of the smoking process, leading to interruption of fermentation, hindered flavor development, and significant batch-to-batch variations. The *Staphylococcus aureus* XUCSB 058 provided by this invention exhibits excellent heat resistance. Experiments show that this strain can maintain a high viable count (>1.9 × 10⁻⁶) even under 50 °C heat stress. 6 (CFU / mL). This characteristic enables it to continuously perform fermentation during the smoking process, achieving simultaneous fermentation and smoking, effectively avoiding fermentation interruption caused by high temperatures, and significantly improving the product's process stability, flavor consistency, and production controllability.

[0024] 4. Possesses multi-enzyme activity and excellent fermentation characteristics, comprehensively optimizing product quality. This strain possesses multiple enzymatic activities, including nitrate reductase, catalase, protease, and lipase, which synergistically promote color formation, flavor compound generation, and texture improvement in fermented meat products. Specifically, nitrate reduction ability contributes to color development and curing, enhancing product appearance; protein and fat hydrolysis activities promote the release of flavor precursors, enriching flavor profiles; and catalase activity inhibits fat oxidation, delaying rancidity and extending shelf life. Furthermore, the strain exhibits environmental adaptability, including acid, salt, and nitrite tolerance, as well as low-temperature resistance, making it suitable for various traditional fermented meat product production conditions.

[0025] 5. High safety, meeting food microbiological application standards. Systematic safety evaluation of the strain showed that it does not carry enterotoxin genes (sea, seb, sec, sed, see) or biogenic amine synthesis genes (hdc, ldc, odc, tdc), thus eliminating the generation of toxins and harmful metabolites at the source; it is non-hemolytic, does not produce mucus, gas, NH3, or H2S, avoiding unpleasant odor and texture problems; it is sensitive to eight common antibiotics, with no risk of drug resistance, meets GRAS (Generally Recognized As Safe) standards, and has good safety for food applications.

[0026] 6. Effectively promotes color formation and stabilization The strain has a strong nitrate-reducing ability, which can effectively promote the formation of nitrosomyoglobin in fermented meat and significantly increase the redness value (α) of the product. Compared to the control group, it increased by 2.52, improving and stabilizing the color of fermented meat and enhancing its visual appeal.

[0027] 7. Significantly enhances the complexity and distinctiveness of product flavor. Smoked bacon inoculated with this strain exhibits significant advantages in the composition of volatile flavor compounds: the types and contents of flavor compounds such as ketones, esters, unsaturated hydrocarbons, aromatics, phenols, and acids are significantly increased; the detection of unique flavor compounds such as 2,5-dimethyl-4-hydroxy-3(2H)-furanone, 4-methyl-3-heptanone, 2-methylpyrazine, β-phellandrene, γ-terpinene, α-terpinene, myrcene, isopropyl hexanoate, and ethyl benzoate endows the product with unique fruity, nutty, roasted, citrus, herbal, pine, and laurel aromas; the overall flavor spectrum is optimized, enhancing the richness, layering, and harmony of the flavor of smoked and fermented meat products, thereby improving product recognition and consumer appeal.

[0028] 8. Reduce nitrite residue and enhance product health attributes Experimental results showed that the nitrite residue in smoked bacon inoculated with XUCSB 058 was reduced by 37.57% compared to the control group, and the final residue was far below the national standard limit (30 mg / kg). This strain has a good nitrite degradation capacity, which helps to reduce potential health risks and is in line with the modern food development trend of "reducing nitrite, lowering salt, and promoting health".

[0029] 9. Promote the industrialization and standardization of traditional meat products. The strains provided by this invention are suitable for the continuous fermentation of various fermented meat products, including cured meats, sausages, hams, and bacon, especially smoked meats. They effectively solve problems associated with traditional processes, such as reliance on natural fermentation, unstable quality, and long production cycles. Through targeted inoculation and controlled fermentation, the flavor, color, and texture of the products can be standardized, facilitating the large-scale, industrialized production of traditional specialty meat products and promoting technological upgrading and increased product added value within the industry.

[0030] Of course, implementing any product or method of the present invention does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0031] Figure 1 The images show the morphological characteristics of Staphylococcus aureus XUCSB 058 on an MSA solid plate and Gram staining under a microscope in Example 1 of this invention. Figure 2 This is a phylogenetic tree diagram of Staphylococcus aureus XUCSB 058 in Example 1 of the present invention; Figure 3 This is a graph showing the change in viable count of Staphylococcus aureus XUCSB 058 in soil under high temperature stress of 50 °C in Example 1 of the present invention; Note: Different letters indicate statistical differences (P<0.05), and error bars represent standard deviations (SD).

[0032] Figure 4 The redness value (a) of the smoked bacon inoculated with Staphylococcus aureus XUCSB 058 in Example 1 of this invention is given by the example. Change diagram; Note: Different letters indicate statistical differences (P<0.05), and error bars represent standard deviations (SD).

[0033] Figure 5 This is a graph showing the residual nitrite content of bacon 10 days after inoculation with Staphylococcus aureus XUCSB 058 in Example 1 of the present invention.

[0034] Note: Different letters indicate statistical differences (P<0.05), and error bars represent standard deviations (SD). Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical terms used below have the same meaning as understood by those skilled in the art.

[0036] Unless otherwise specified, the test materials and reagents used in the following examples are commercially available or prepared by known methods.

[0037] Unless otherwise specified, all techniques or conditions described in the embodiments can be performed in accordance with the techniques or conditions described in the literature in this field or in the product manual. Unless otherwise specified, the quantitative experiments in the following embodiments are all repeated three times or more, and the results are averaged.

[0038] Example 1: 2. Experimental Materials and Methods 2.1 Experimental Materials 2.1.1 Preparation of culture medium MSA liquid culture medium (1000 mL): 3 g beef extract, 10 g peptone, 25 g NaCl, 10 g D-mannitol, added to distilled water. Adjust the pH to approximately 7.2, then sterilize at 121 ℃ for 20 min.

[0039] MSA solid medium (1000 mL): 3 g beef extract, 10 g peptone, 25 g NaCl, 10 g D-mannitol, 18 g agar powder, and distilled water. Adjust the pH to approximately 7.2 and sterilize at 121 °C for 20 min.

[0040] Fermentation medium for producing gas and acid from glucose (100 mL): 1 g peptone, 0.5 g NaCl, 1 g glucose, add distilled water, adjust pH to 7.4, add a trace amount of 1.6% bromocresol purple solution (0.16 g dissolved in 10 mL of 95% ethanol solution) until the solution turns purple, dispense 10 mL into test tubes, invert the Durham tubes into the test tubes and remove the air, sterilize at 121℃ for 20 min.

[0041] Arginine ammonia-producing medium (100 mL): 0.5 g peptone, 0.5 g yeast extract, 0.5 g beef extract, 0.25 g NaCl, 0.05 g glucose, 0.2 g ammonium citrate, 0.2 g dipotassium hydrogen phosphate, 1 g L-arginine, dissolved in distilled water, pH adjusted to 5.3. Dispense into test tubes, 10 mL per tube, add inverted Durham tubes, remove air, and sterilize at 121°C for 20 min.

[0042] Ferrous sulfate agar medium (100 mL): 0.3 g beef extract, 0.3 g yeast extract, 1 g peptone, 0.02 g ferrous sulfate, 0.03 g sodium thiosulfate, 0.5 g NaCl, 1.2 g agar. Mix well in distilled water and adjust pH to 7.4. Dispense into test tubes, 10 mL per tube, and sterilize at 121°C for 20 min. After sterilization, remove from heat and stand upright to allow it to solidify into a homogeneous solid for later use.

[0043] Amino acid decarboxylase detection medium (100 mL): 0.5 g peptone, 0.3 g beef extract, 0.1 g glucose, 0.002 g bromocresol purple, and 0.5 g amino acids (L-lysine and L-ornithine, respectively) dissolved in distilled water, adjusted to pH 6.8. Dispense into test tubes, 10 mL per tube, and sterilize at 121°C for 20 min.

[0044] 2.1.2 Biochemical reagents The biochemical reagents required for the experiment were purchased from Beijing Solarbio Technology Co., Ltd. or Shanghai McLean Biotech Co., Ltd.

[0045] 2.2 Experimental Methods 2.2.1 Strain screening, identification and preservation The bacterial strains required for the experiment were screened from cured pork from Changsha, Hunan. Primers were used. 7F: 5'-CAGAGTTTGATCCTGGCT-3', (SEQ ID NO.2) 1540R: 5'-AGGAGGTGATCCAGCCGCA-3', (SEQ ID NO.3) PCR amplification of 16S rDNA was performed. PCR conditions were: 95 °C pre-denaturation for 5 min; 95 °C denaturation for 15 s, 57 °C annealing for 15 s, 72 °C extension for 1 min 30 s, 34 cycles; 72 °C final extension for 10 min; reaction terminated at 4 °C. After purification, the samples were sent to Shanghai Sangon Biotech for sequencing. Sequence alignment was performed using NCBI Nucleotide BLAST after receiving the sequencing results. The bacterial culture was mixed 1:1 with 50% glycerol (v / v) in cryovials and stored at -80 °C in the Key Laboratory of Meat Microbiology and Control, Hefei University of Technology. The strain was then deposited at the China General Microbiological Culture Collection Center (CGMCC) using the streak agar method.

[0046] 2.2.1 Physicochemical properties of Staphylococcus aureus XUCSB 058: 1. Hemolytic Using a sterile inoculation loop, streak the activated third-generation bacterial culture from MSA liquid medium onto a Columbia blood agar plate, incubate at 37°C for 48 hours, and observe whether a hemolytic zone appears around the bacterial strain.

[0047] 2. Nitrate Reduction Characteristics Nitrate-reducing solid medium: MSA liquid medium was prepared by adding 0.2% potassium nitrate and sterilizing. The isolated and purified colonies were inoculated onto the nitrate-reducing medium and incubated upside down at 37 °C for 8 h. 1 mL of Griess reagent A and 1 mL of reagent B were added to the colonies growing in the center of the medium. After reacting for one minute, the remaining liquid was poured off, and the presence and size of the red color zone around the bacterial strain were observed.

[0048] 3. Protease activity Add 5% skim milk powder to MSA solid medium and sterilize at 115 °C for 20 min. Inoculate onto SM medium using the single colony inoculation method and incubate at 37 °C for 48 h. Observe the decomposition and size of the clear zone around the strain.

[0049] 4. Lipase activity Add 1% glyceryl tartrate to MSA solid medium, dissolve the soluble substance uniformly by sonication, and sterilize at 115 °C for 20 min. Inoculate the glyceryl tartrate medium using the single colony inoculation method, and incubate at 37 °C for 72 h. Observe the presence and size of the clear zone decomposition of the strain.

[0050] 5. Catalase positive test Place a drop of 3% hydrogen peroxide solution on a glass slide, pick up a single colony of the bacteria to be tested with an inoculation needle, smear it in the hydrogen peroxide solution, and observe whether the strain produces bubbles.

[0051] 6. Produces viscosity Use an inoculation needle to directly pick up a single colony growing on MSA solid medium and observe whether the strain exhibits filamentous behavior.

[0052] 7. Detection of glucose gas and acid production Inoculate 1% bacterial culture into a test tube containing 10 mL of glucose-generating liquid culture medium. Place the Durham tube upside down at the bottom of the tube to remove air, and incubate at 37 °C and 150 rpm for 24 h. Observe whether bubbles are generated in the Durham tube and whether the liquid turns yellow.

[0053] 8. NH3 production detection The test strain was inoculated with a 1% bacterial suspension into a test tube containing arginine-containing ammonia-producing medium. Sterile liquid paraffin was added to cover the surface of the medium, and the tube was incubated at 37 ℃ and 150 rpm for 48 h. The phenomenon of bubble formation in the Durham tubes was observed.

[0054] 9. Detection of biological amines The test strain was inoculated at 1% bacterial concentration into test tubes containing amino acid decarboxylase detection media containing L-lysine and L-ornithine, respectively. The tubes were covered with sterile liquid paraffin and incubated at 37 ℃ and 150 rpm for 48 h. Color changes were observed. A yellow color indicates a negative result; a yellow color followed by a purple color indicates a positive result.

[0055] 10. H2S detection Use a sterile colony needle to pick a single colony and insert it into a test tube containing ferrous sulfate agar medium. Incubate at 37°C and 150 rpm for 48 hours and observe whether a black color appears.

[0056] 11. NaNO2 resistance test 1% of the activated third-generation bacterial culture was inoculated into 150 mg / L MSA liquid enrichment medium. After incubation at 37°C and 150 rpm for 24 h, turbidity was observed and OD was recorded. 600 .

[0057] 12. Acid resistance test 1% of the activated third-generation bacterial culture was inoculated into MSA liquid medium at pH 4.5, 5.0, and 5.5. After incubation at 37°C and 150 rpm for 48 h, turbidity was observed and OD was recorded. 600 .

[0058] 13. Salt tolerance test 1% of the activated third-generation bacterial culture was inoculated into MSA liquid enrichment medium containing 10% NaCl. After incubation at 37°C and 150 rpm for 48 h, turbidity was observed and OD was recorded. 600 .

[0059] 14. Low-temperature resistance test 1% of the activated third-generation bacterial culture was inoculated into MSA liquid enrichment medium and incubated at 10°C for 48 hours. Turbidity was observed and OD was recorded. 600 .

[0060] 2.2.2 Virulence gene detection Direct PCR was used to determine whether strain XUCSB 058 contained pathogenic genes and biogenic amine-producing genes. Genes detected included sea, seb, sec, sed, and see enterotoxin genes, histidine decarboxylase gene hdc, lysine decarboxylase gene ldc, ornithine decarboxylase gene odc, and tyrosine decarboxylase gene tdc. Primer design, gene length, and PCR annealing temperature (Tm) are shown in Table 1. PCR conditions were: initial denaturation at 95 °C for 5 min; denaturation at 95 °C for 15 s, annealing at Tm (°C) for 15 s, extension at 72 °C (calculated based on a gene length of 1000 bp as 1 min), 34 cycles; and final extension at 72 °C for 10 min.

[0061] Table 1. Primers and annealing temperatures required for PCR detection of enterotoxin and amine-producing genes in strain XUCSB 058.

[0062] 2.2.3 Antibiotic susceptibility testing The antibiotic susceptibility of strain XUCSB 058 was determined using the KB method of disk agar diffusion. 100 μL of activated, third-generation, late-log phase *Staphylococcus aureus* XUCSB 058 suspension was evenly spread onto MSA solid medium. After the bacterial suspension on the plate dried, antibiotic disks containing eight antibiotics (rifampin (5 μg), chloramphenicol (30 μg), kanamycin (30 μg), streptomycin (10 μg), tetracycline (10 μg), penicillin (10 μg), vancomycin (30 μg), and gentamicin (10 μg)) were affixed to the plate with sterile forceps. The plate was incubated at 37 ℃ for 48 h, and the diameter of the inhibition zone (mm) was measured. The size of the inhibition zone represents the sensitivity of the strain to the tested drugs.

[0063] 2.3 Detection of thermostable viable count of Staphylococcus aureus XUCSB 058 in soil At an inoculation rate of 2%, *Staphylococcus aureus* XUCSB 058 was passaged every 12 hours. Three generations of activated *Staphylococcus aureus* XUCSB 058 were incubated at 37 °C and 50 °C on shakers at 150 rpm, respectively. Samples were taken every 3 hours to measure the viable cell count at 0 h, 3 h, and 6 h. The bacterial suspension was serially diluted, plated on MSA agar plates, and incubated at 37 °C for 48 h. The experimental results were then observed.

[0064] 2.4 Application of Staphylococcus aureus XUCSB 058 in Smoked Cured Meat 2.4.1 Preparation of Smoked Cured Meat The pork used was selected from the hind leg meat of free-range pigs, cut into strips approximately 35 cm long, 5 cm wide, and 3.5 cm thick, with skin, at a weight of about 0.5 kg. Seasonings were added, and the meat was semi-dry cured. The seasonings used per kg of pork were: 0.025 kg salt, 0.0001 kg sodium nitrite, 0.004 kg Sichuan peppercorns, 0.01 kg white sugar, and 0.0015 kg white liquor. The experimental group was inoculated with bacteria at a concentration of 2 × 10⁻⁶ bacteria. 7 CFU / g. The bacterial strain was activated third-generation Staphylococcus aureus XUCSB 058. After washing three times with sterile water, it was resuspended in a bacterial suspension of 1% sterile water relative to the weight of the fermented meat. It was then chopped, mixed thoroughly, and cured at 4 ℃ for 1 day, turning over every 6 hours. The control group received no bacterial strain but the same proportion of sterile water. Afterward, the meat was hung in a pre-sterilized constant temperature and humidity chamber for fermentation. The procedure was: fermentation at 15 ℃ for 6 days, relative humidity 60%. It was then removed and air-dried for 1 day in a sunny outdoor environment with an outdoor temperature below 15 ℃. Applewood was used as the smoking material, and the meat was smoked at 45 ℃ for 6 hours, then hung in a ventilated area to dissipate heat for 6 hours. Finally, it was stored at 10 ℃ for 2 days to allow the flavor to mature. Sampling times were 0, 4, 7, and 10 days.

[0065] 2.4.2 Color Changes of Smoked Cured Meat Take a lean meat sample of the cured pork, approximately 0.5 cm thick. Use a colorimeter (TS7600, 3nh, Shenzhen, China) to measure the redness value (α) of the smoked cured pork. Three parallel determinations were performed.

[0066] 2.4.3 Nitrite Residue in Smoked Cured Meat The spectrophotometric method in GB 5009.33-2016 was used to detect the residual amount of nitrite in cured meat.

[0067] 2.4.4 Detection of flavor compounds in smoked bacon (1) Sample pretreatment Weigh 2.0 g of chopped smoked bacon sample into a 20 mL headspace vial, and add 10 μL of 0.1 g / L 2-methyl-3-heptanone as an internal standard. Headspace solid-phase microextraction (SPME) was used. For the first use, a syringe was used for injection. The SPME extraction head was first aged at the GC inlet (250 °C) for 20 min. Then, the microextraction needle was inserted into the headspace vial, and extraction was performed at 60 °C for 30 min. After that, the sample was manually fed into the inlet and desorbed for 5 min.

[0068] (2) GC conditions: The chromatographic column was a DB-5 MS capillary column (60 m × 0.32 mm, 1 μm); the carrier gas was high-purity helium; the flow rate was 0.8 mL / min; the injection port temperature was 250 ℃, and the splitless mode was used. The solvent delay was 1 min. The initial column temperature was 40 ℃, and it was held for 5 min. The temperature program was as follows: the temperature was increased to 90 ℃ at a rate of 2 ℃ / min, held for 0 min, then increased to 100 ℃ at a rate of 5 ℃ / min, held for 0 min, and then increased to 230 ℃ at a rate of 10 ℃ / min, held for 8 min.

[0069] (3) MS conditions: Full scan mode was used, and the mass spectrometer scanning mass was 45-500 m / z. The ion source was EI, the ion source temperature was 230 ℃, the electron energy was 70 eV, and the sample inlet temperature was 250 ℃.

[0070] The content of each volatile component is calculated using the following formula: The amount of flavor compound (mg / kg) = (C0×V0 / m)×(A1 / A2), where C0 is the concentration of the internal standard (mg / L), V0 is the injection volume of the internal standard (µL), and m is the mass of the chopped sample (g). A1 is the peak area of ​​the compound, and A2 is the peak area of ​​the internal standard.

[0071] 3. Experimental Results 3.1 Isolation, purification, and sequencing identification of Staphylococcus aureus XUCSB 058 The colony status of *Staphylococcus aureus* XUCSB 058 streaked on MSA plates and incubated at 37°C for 48 h, and the Gram staining results of the strain under a 60x magnification optical microscope are shown in the figure. Figure 1 The strain on MSA agar plates was approximately 0.12 ± 0.09 cm in size, white, with slightly transparent colonies. The surface and edges of the colonies appeared moist and smooth, without a raised center. After Gram staining, it turned purple, thus identifying it as a Gram-positive bacterium.

[0072]

[0073] According to NCBI comparison, the sequence is similar to Staphylococcus edaphicus strain BPs2 showed 99.86% sequence similarity. To further determine the strain's phylogenetic relationship and taxonomic position, a phylogenetic tree was constructed, and the results are as follows: Figure 2 As shown, Staphylococcus aureus XUCSB 058 and Staphylococcus edaphicus BPs2 (MT269536.1) clustered in a phylogenetic tree, therefore, this strain was identified as Staphylococcus aureus (Staphylococcus aureus). Staphylococcus edaphicus This laboratory named it Staphylococcus aureus XUCSB 058 ( Staphylococcus edaphicus XUCSB 058 is deposited at the Key Laboratory of Meat Microbiology and Control, Hefei University of Technology; it is also deposited at the China General Microbiological Culture Collection Center (CGMCC) on June 24, 2025, with the accession number CGMCCNo.34994, located at No.3, Courtyard 1, Beichen West Road, Chaoyang District, Beijing.

[0074] 3.2 Physicochemical properties of Staphylococcus aureus XUCSB 058 The physicochemical properties of *Staphylococcus aureus* XUCSB 058 are shown in Table 2. As can be seen from the table, *Staphylococcus aureus* XUCSB 058 has strong nitrate-reducing properties, which are beneficial for the color development and solidification of meat products. It also has strong protein and fat hydrolysis properties, which are conducive to the formation of volatile flavor compounds in meat products, improving the texture of fermented meat and the final product's taste. The strain has hydrogen peroxide decomposition properties, thus helping to prevent myoglobin oxidation, stabilize and maintain the ideal bright red or pink color of fermented meat products, inhibit excessive lipid oxidation, prevent rancidity, improve the oxidative stability and overall quality consistency of the product, and extend shelf life. The strain is not hemolytic, indicating that it does not produce hemolysins that can lyse red blood cells, and has the potential for safe use. The strain does not produce mucilage, gas, NH3, H2S, or amines, meaning that it will not produce interfering off-flavor byproducts when applied to fermented meat. It has acid-producing properties, which can inhibit the growth of spoilage bacteria and pathogenic bacteria to a certain extent, promoting the formation of good sensory characteristics in the final product. The strain exhibits tolerance to low temperatures of 10 °C, 10% NaCl, and 150 mg / L NaNO2, and maintains good growth characteristics even at pH 4.5. Therefore, it demonstrates good adaptability to the fermentation environment of low-temperature, high-salt fermented meats produced in climatic conditions, such as cured meats and sausages made in winter, and can maintain continuous fermentation even under less than ideal fermentation conditions. Based on the above physicochemical characteristics, this strain is an excellent candidate strain with significant development value and application potential in fermented meat products.

[0075] Table 2. Fermentation characteristics of Staphylococcus aureus XUCSB 058 in soil

[0076]

[0077]

[0078]

[0079] Note: "+" and "-" indicate whether the reaction is positive or negative. The numbers represent OD values. 600 The average absorbance measured.

[0080] 3.3 Detection of virulence genes in Staphylococcus aureus XUCSB 058 Table 3 shows the PCR results of enterotoxin and amine-producing genes in *Staphylococcus aureus* XUCSB 058. The results indicate that *Staphylococcus aureus* XUCSB 058 does not contain virulence genes. The enterotoxin encoding genes *sea*, *seb*, *sec*, *sed*, and *see* were not detected in the strain, indicating that this bacterium does not secrete potent toxins that can directly attack human intestinal cells, thus preventing bacterial food poisoning. No biogenic amine-forming genes, such as histamine (hdc), cadaverine (ldc), putrescine (odc), and tyramine (tdc), were also detected in the strain. This indicates that the strain lacks amino acid decarboxylases, fundamentally eliminating the harm to food and human health caused by biogenic amine formation. Therefore, *Staphylococcus aureus* XUCSB 058 has the potential for relatively safe application in fermented meat.

[0081] Table 3. PCR detection of enterotoxin and amine-producing genes in Staphylococcus aureus XUCSB 058

[0082] Note: "+" and "-" indicate whether the phenomenon is positive or negative.

[0083] 3.4 Antibiotic susceptibility test of Staphylococcus aureus XUCSB 058 The susceptibility of bacteria to antibiotics was studied using the antibiotic susceptibility testing method, with the size of the inhibition zone representing the degree of antibiotic sensitivity. The results of the antibiotic susceptibility test for *Staphylococcus aureus* XUCSB 058 are shown in Table 4. The results indicate that *Staphylococcus aureus* XUCSB 058 exhibited inhibition zones against all eight commonly tested antibiotics in this study, demonstrating susceptibility. Among them, gentamicin, rifampin, and kanamycin showed the largest inhibition zones, indicating the highest sensitivity, with inhibition zone sizes of 15.18 ± 0.94 mm, 14.06 ± 1.08 mm, and 13.62 ± 0.73 mm, respectively. Therefore, *Staphylococcus aureus* XUCSB 058 is a very low-risk, non-drug-resistant bacterium, and common antibiotics can effectively inhibit or kill this bacterium at certain doses. It is also unlikely that this bacterium will transfer resistance genes to the intestinal flora or other pathogens through the food chain or environment. Meeting GRAS standards, it possesses food microbiological safety, ensuring the safety of fermented foods.

[0084] Table 4. Drug susceptibility of Staphylococcus aureus XUCSB 058

[0085] 3.5 Changes in the number of thermostable Staphylococcus aureus XUCSB 058 cells The inoculum was subcultured every 12 hours in MSA liquid medium at a 2% inoculum concentration. The activated third-generation Staphylococcus aureus XUCSB 058 was then incubated at 37 °C and 150 rpm for 6 hours on a shaker. Changes in viable cell count were monitored, and the results are as follows: Figure 3 As shown in the figure, the viable count of *Staphylococcus aureus* XUCSB 058 in the control group continued to increase after 6 hours of cultivation at 37 ℃ and 150 rpm in a shaker, indicating that the strain was still in a highly active state during the logarithmic growth phase. In the experimental group, *Staphylococcus aureus* XUCSB 058, after continuous high-temperature stress at 50 ℃, had a viable count density of 1.92 × 10⁻⁶ at 6 hours. 6 The CFU / mL count still indicates a high viable bacterial level, demonstrating that *Staphylococcus aureus* XUCSB 058 can withstand temperatures up to 50 °C. This characteristic meets the requirement for smoked fermented meat to maintain continuous fermentation even after short-term high-temperature smoking. This characteristic has significant practical implications for the high-quality development of smoked fermented meat products.

[0086] 3.6 Application of Staphylococcus aureus XUCSB 058 in Smoked Cured Meat 3.6.1 Color changes of smoked bacon The effect of soil-inoculated Staphylococcus aureus XUCSB 058 (C58) on the redness value (a) of smoked bacon within 10 days was measured using a colorimeter. The changes in ) resulted in the following: Figure 4As shown. From day 4 until day 10, when fermentation was completed and storage continued for two more days, the redness value (a) of the smoked bacon inoculated with C58 in the experimental group was measured. The redness value on day 10 was consistently higher than that of the control group (smoked bacon without inoculation). The average value was 15.94, which was 2.52 higher than that of the control group. This indicates that inoculation with Staphylococcus aureus XUCSB 058 can improve the color of smoked and fermented meat products and promote the formation of red solidification.

[0087] 3.6.2 Nitrite Residue in Smoked Cured Meat After 10 days of fermentation, the residual nitrite level in the smoked bacon was as follows: Figure 5 As shown in the figure, the average nitrite residue in the control group (uninoculated smoked bacon) was 8.73 mg / kg. In contrast, the nitrite residue in the experimental group (inoculated with C58) was 5.45 mg / kg, a reduction of 37.57% compared to the control group. This is significantly lower than the national food safety standard GB 2760-2014, which stipulates that the nitrite residue in fermented meat products must not exceed 30 mg / kg. This indicates that *Staphylococcus aureus* XUCSB 058 has a good ability to degrade nitrite.

[0088] 3.6.3 Detection of volatile flavor compounds in smoked bacon Volatile compounds (VOCs) in smoked bacon in the Staphylococcus aureus C58 inoculation group and the uninoculated CK group were extracted by headspace solid-phase microextraction (HS-SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS) on an Agilent 8890-5977B system. The results are shown in Table 5. A total of 32 VOCs were detected, including 4 ketones, 3 alcohols, 6 esters, 5 unsaturated hydrocarbons, 5 aromatic hydrocarbons and phenols, 5 acids, and 4 other compounds. The formation of VOCs in fermented meat products mainly originates from exogenously added flavorings and endogenous biochemical reactions, the latter mainly including microbial and endogenous enzyme-driven lipid oxidation, protein (amino acid) degradation, and carbohydrate metabolism. A total of 12 VOCs were detected in the CK group, including 3 alcohols, 2 esters, 1 unsaturated hydrocarbon, 2 aromatic hydrocarbons and phenols, 1 acid, and 3 other compounds. A total of 23 volatile compounds were detected in the group inoculated with Staphylococcus aureus XUCSB 058, including 4 ketones, 4 esters, 5 unsaturated hydrocarbons, 4 aromatic hydrocarbons and phenols, 4 acids, and 2 other compounds. Among the volatile flavor compounds, ketones and alcohols were unique to the C58 and CK groups, respectively. For other types of flavor compounds (such as esters, unsaturated hydrocarbons, aromatic hydrocarbons and phenols, and acids), the C58 inoculation group showed significantly more detected species than the control group. These results indicate that inoculation with Staphylococcus aureus XUCSB058 helps promote the formation of flavor in fermented meat, increasing its richness and diversity.

[0089] Ketones are formed through the secondary oxidation of aldehydes and are the final products of fatty acid oxidation and decomposition in meat products. With increasing carbon chain and diketone content, ketones exhibit strong floral characteristics, typically possessing meaty and buttery aromas, and are usually products of the initial stage of the Maillard reaction. The *Staphylococcus aureus* C58 group inoculated with this bacterium contained four types of ketones. Acetone has a high aroma threshold and is perceived as fruity or sweet at lower concentrations. 3-Pentanone, a type of fatty ketone, has an ether-like sensation and is perceived as fruity or sweet. 4-Methyl-3-heptanone, a type of methyl ketone, is a characteristic product of lipid β-oxidation, contributing grassy, ​​fatty, and fruity aromas. Among the ketones in smoked bacon inoculated with *Staphylococcus aureus* C58, 2,5-dimethyl-4-hydroxy-3(2H)-furanone was the most abundant. It is an important aroma compound in fruits and also possesses strawberry-like aromas in some wines, but has not been reported in fermented meat aromas; therefore, it belongs to the volatile aroma compounds unique to smoked bacon in the C58 group.

[0090] Alcohols are formed through various biochemical pathways, such as carbohydrate metabolism, reduction of methyl ketones and aldehydes, amino acid metabolism, and lipid oxidation. Eucalyptol, an epoxide, possesses a cool eucalyptus aroma and camphor odor, and is widely used in pharmaceuticals, food flavorings, and daily chemicals. 2-Methyl-2-hexanol is a fatty alcohol with a strawberry aroma. (R)-3-pyrrolidone is a nitrogen-containing heterocyclic alcohol, classified as a thiazole, thiophene, and pyridine in flavorings. It had the highest content in the uninoculated group and has not been previously reported in the flavor compounds of meat products; its presence may be due to non-enzymatic thermal degradation of proteins or amino acids in the sample or the presence of exogenous bacteria.

[0091] Esters are highly aromatic compounds with very low odor thresholds, contributing fruity notes to fermented meats. Esters are primarily formed through esterification reactions between short-chain acids and alcohols. Methyl acetate has a sweet and fruity flavor, while methyl isovalerate has an apple aroma, characteristic of group CK. Ethyl octanoate has a brandy aroma and fruity notes of pineapple and apple. Ethyl benzoate has a fruity aroma and is naturally found in peach, pineapple, and tobacco. Ethyl valerate is a permitted food flavoring used in flavorings such as strawberry, apple, and jackfruit. Isopropyl hexanoate is also a permitted food flavoring, reportedly detected in strawberries near ripeness. These four esters are characteristic of group C58 smoked bacon; although present in low amounts, their very low odor thresholds contribute significantly to the flavor of smoked bacon.

[0092] Unsaturated hydrocarbons, such as terpenes, are commonly reported in fermented meats. α-Phappenene and α-terpinene have a fresh, slightly spicy citrus aroma, while β-phappenene, γ-terpinene, α-terpinene, and myrcene contribute herbal, pine, and turpentine notes, as well as typical pepper and bay leaf aromas. Several of these substances are commonly found in the volatile components of spices and smoking materials. However, β-phappenene, γ-terpinene, α-terpinene, and myrcene are specific to the inoculated group; therefore, they are likely the result of the combined effects of microbial inoculation and the spice and smoking processes.

[0093] Among the results for aromatics and phenols, toluene can be obtained by cracking free tyrosine, or by unsaturated hydrocarbons produced from the auto-oxidation and thermal oxidative decomposition products of fatty acids. Toluene is commonly found in volatile organic compounds emitted during pork grilling or in beef cooked at high temperatures, and is generally not a major flavor contributor. 4-Ethyl-2-methylphenol has a similar structure to 4-ethylguaiacol, which has been widely recognized as a key flavor compound in smoked bacon. Its presence can be considered an effective chemical marker of the smoking process, but its content was low in the control group (CK) and not observed in the microbial inoculation group, suggesting possible microbial transformation or degradation. 4-Propylphenol has a distinctive aromatic odor and is a type of flavoring agent; studies have reported its availability from lignin oil. Propoxybenzene has a strong aromatic odor and can be used to synthesize flavorings and fragrances. 1,2,3-Trimethylbenzene itself has a strong aromatic odor but is not used directly as a flavoring agent; it is used industrially as an important raw material for the artificial synthesis of flavorings.

[0094] Short-chain acids are mainly produced by microbial carbohydrate metabolism or amino acid conversion, while long-chain and medium-chain fatty acids come from the hydrolysis of triglycerides and phospholipids, as well as lipid degradation. Phenylacetic acid is the most abundant acid in the C58 inoculation group, with a honey-like flavor profile, thus contributing a sweet aroma to fermented meat. Propylene acid is a fatty acid, but not a flavor compound, and is present in extremely low amounts in natural food systems. The cinnamic acid structures of 3,4-dimethoxycinnamic acid and 3,5-dimethoxycinnamic acid have applications in the spice industry, possibly originating from plant-based ingredients added during the processing of cured meat, and may play a positive role in the oxidative stability of the product. 3,5-Dimethoxycinnamic acid is explicitly labeled as a synthetic flavoring agent under the flavoring and fragrance category; the difference may be due to different biochemical reactions occurring after microbial inoculation. 5-tert-butylisophthalic acid is an aromatic acid, but there are no reports of it being used as a volatile flavor compound.

[0095] Among other substances, 2-methylpyrazine possesses aromas of nuts, cocoa / chocolate, roasting, and meat, and exhibits a pronounced chocolate aroma when diluted to specific concentrations. It is naturally found in various high-temperature or fermented foods such as coffee, roasted barley, roasted beef, peanuts, potato chips, and dairy products, and is a typical product of Maillard reactions or microbial fermentation, characteristic of smoked bacon from the C58 inoculation group. O-cymenes possess herbal and woody aromas and have wide applications in the flavor and fragrance industry. They are important components of many plant essential oils and are also present in hop extracts. In smoked bacon, the content of 2-methylpyrazine in the C58 inoculation group is higher than that in the control group. Itaconic anhydride is a fatty acid present in mainstream smoke but is not a flavor contributor. 4-Methylthiazole is a flavor intermediate with aromas of green, vegetables, meat, and onions. It is found in cooked beef and pork, coffee, cocoa, peanuts, and other substances. It is a natural equivalent flavoring agent. Its presence is a marker of Maillard reaction and thiamine degradation during processing. Its nutty and meaty aromas are important components of the basic flavor of cured meat and are unique to the CK group.

[0096] The results indicate that inoculation with Staphylococcus aureus XUCSB 058 effectively enhances the diversity of volatile compounds in the fermentation system, thereby promoting the formation of the unique flavor of smoked bacon. Overall, the application of this strain significantly enhances the richness and complexity of the final product's flavor. This study provides support for the subsequent development of smoked and fermented meat products with continuous fermentation processes, contributing to the industrialization of my country's local specialty fermented meat products and improving their overall quality.

[0097] Table 5. Volatile compound content of bacon inoculated with Staphylococcus aureus XUCSB 058 in soil.

[0098] Note: Different lowercase letters indicate statistically significant differences (P < 0.05) in the data of different sample groups on the same line; ND indicates that the corresponding compound was not detected.

[0099] Example 2: The difference between this embodiment and Embodiment 1 lies in the subtle differences in the preparation steps of the smoked bacon, specifically: The ingredients used to prepare 1 kg of pork were: 0.02 kg salt, 0.00005 kg sodium nitrite, 0.002 kg Sichuan peppercorns, 0.005 kg white sugar, and 0.001 kg white liquor. The experimental group was inoculated with bacteria at a concentration of 1.5 × 10⁻⁶. 7CFU / g. The bacterial strain was activated third-generation Staphylococcus aureus XUCSB 058. After washing three times with sterile water, it was resuspended in a bacterial suspension of 1% sterile water relative to the weight of the fermented meat. It was then chopped, mixed thoroughly, and cured at 3 ℃ for 1.5 days, turning over every 6 hours. The control group received no bacterial strain but the same proportion of sterile water. Afterward, the meat was hung in a pre-sterilized constant temperature and humidity chamber for fermentation. The procedure was: fermentation at 10 ℃ for 8 days, relative humidity 50%. It was then removed and air-dried for 1 day in a sunny outdoor environment with an outdoor temperature below 15 ℃. Applewood was used as the smoking material, and the meat was smoked at 40 ℃ for 8 hours, then hung in a ventilated area to dissipate heat for 6 hours. Finally, it was stored at 10 ℃ for 2 days to allow the flavor to mature.

[0100] Example 3: The difference between this embodiment and Embodiment 1 lies in the subtle differences in the preparation steps of the smoked bacon, specifically: The ingredients used to prepare 1 kg of pork were: 0.03 kg salt, 0.0002 kg sodium nitrite, 0.006 kg Sichuan peppercorns, 0.02 kg white sugar, and 0.002 kg white liquor. The experimental group was inoculated with bacteria at a concentration of 1.5 × 10⁻⁶. 7 CFU / g. The bacterial strain was activated third-generation Staphylococcus aureus XUCSB 058. After washing three times with sterile water, it was resuspended in a bacterial suspension of 1% sterile water relative to the weight of the fermented meat. It was then chopped, mixed thoroughly, and cured at 5℃ for 0.5 days, turning over every 6 hours. The control group received no bacterial strain but the same proportion of sterile water. Afterward, the meat was hung in a pre-sterilized constant temperature and humidity chamber for fermentation. The procedure was: fermentation at 20℃ for 4 days, with a relative humidity of 70%. It was then removed and air-dried for 1 day in a sunny outdoor environment with an outdoor temperature below 15℃. Applewood was used as the smoking material, and the meat was smoked at 50℃ for 4 hours, then hung in a ventilated area to dissipate heat for 6 hours. Finally, it was stored at 10℃ for 2 days to allow the flavor to mature.

[0101] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A strain of Staphylococcus aureus XUCSB 058, characterized by its resistance to smoke and high temperatures, is characterized by: The accession number is CGMCCNo.34994.

2. The application of Staphylococcus aureus XUCSB 058 as described in claim 1 in the fermentation preparation of meat products.

3. The application of Staphylococcus aureus XUCSB 058 as described in claim 1 in the preparation of meat fermentation inoculants.

4. A meat fermentation agent with resistance to high temperatures and smoke, characterized in that, Its main components include one or more of the following: Staphylococcus aureus XUCSB 058 as described in claim 1, its bacterial suspension or fermentation broth.

5. A method for improving the flavor and quality of fermented smoked meat products, characterized in that, In the preparation of smoked meat fermented products, the meat fermentation agent described in claim 4 can be added.

6. The method according to claim 5, characterized in that, The meats mentioned include pork, beef, mutton, or their heart, liver, lungs, and kidneys.

7. The method according to claim 5, characterized in that, The fermented meat products include bacon, sausage, ham, and sausage.

8. The method according to claim 5, characterized in that, The main component of the meat fermentation inoculant is *Staphylococcus aureus* XUCSB 058, and the concentration of *Staphylococcus aureus* XUCSB 058 in the meat fermentation inoculant is 1.5~2.5×10⁻⁶. 7 CFU / g.

9. The method according to claim 5, characterized in that, The process includes the following steps: cutting the meat into long strips, adding ingredients and meat fermentation agents, and semi-dry marinating; then hanging it in a pre-sterilized constant temperature and humidity chamber for fermentation; then taking it out for hanging smoking, and finally removing it to mature; the ingredients include salt, sodium nitrite, Sichuan peppercorns, white sugar, and white wine.

10. The method according to claim 9, characterized in that, The process includes the following steps: cut the meat into long strips, add 2.0-3.0% salt, 0.005-0.02% sodium nitrite, 0.2-0.6% Sichuan peppercorns, 0.5-2.0% white sugar, and 0.1-0.2% white wine by weight; Add Staphylococcus aureus XUCSB 058 to a concentration of 1.5~2.5×10⁻⁶. 7 CFU / g; semi-dry pickling at 3~5℃ for 0.5~1.5 days; then hanging in a pre-sterilized constant temperature and humidity chamber for fermentation; fermentation program: fermentation at 10~20℃ for 4~8 days, relative humidity 50~70%; then take it out, hang it at 40~50℃ for smoking for 4~8 hours, hang it in a ventilated place to dissipate heat for 4~8 hours; finally, store at 10℃ for 1~3 days to allow its flavor to mature.

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