Lactobacillus mucilaginosus INM3119 as well as preparation and application thereof

Abstract

The invention provides a strain of fermented lactobacillus mucus INM3119 as well as preparation and application thereof, the strain of the fermented lactobacillus mucus INM3119 is preserved in Guangdong Province Microbial Culture Collection Center on August 13, 2024, the preservation number is GDMCC NO: 65005, and the preservation address is No. 59 building, No. 100 Courtyard, Xianlie Middle Road, Guangzhou City, Guangdong Province. The lactobacillus mucus INM3119 has the advantages that the lactobacillus mucus INM3119 can improve the content and flavor of 5-hydroxymethylfurfural in fructus momordicae juice, can be used for cooking rice in the later period, and can effectively improve the flavor of the product and prolong the shelf life of the product.

Description

Technical Field

[0001] The invention belongs to the technical field of industrial microorganisms and relates to a fermented mucus lactobacillus INM3119 and a preparation method and application thereof. Background Art

[0002] Rice is the most widely consumed staple food for people in China and Southeast Asia. How to develop this traditional staple food into a new type of convenient rice ball food that can be industrially mass-produced is a topic of great concern to many countries and companies.

[0003] 5-Hydroxymethylfurfural (5-HMF) is a naturally occurring compound, a cyclic compound formed by the condensation reaction of fructose under acidic conditions, with a special aroma at room temperature. 5-HMF is widely found in nature, such as honey, fruit juice, and smoked foods. 5-HMF is widely present in dairy products and caramelized foods, and has a certain effect on the color and flavor of food. It can be used as an indicator of the freshness and browning degree of food. With the deepening of research, the antioxidant and antibacterial biological activities of 5-HMF have gradually been discovered. The application prospect of preparing food with 5-HMF as raw material is very promising. It can not only improve learning and memory, lower blood sugar, and protect nerve cells, but also 5-HMF does not pose a serious health threat within the daily human intake range. However, the current preparation process still has many challenges such as time-consuming and energy-consuming, difficult to control the reaction process, and unsuitable for industrial production.

[0004] 5-HMF can be synthesized by a variety of methods, among which the most common method is the causticization method. Biomass such as cellulose or lignin is pretreated to convert it into sugar substances under acidic conditions. Then, the sugar substances are converted into furfural through acidic hydrolysis reaction, and finally, furfural is oxidized to 5-hydroxymethylfurfural through oxidation reaction. However, this method has the problem that the catalyst is not easy to separate and recover, resulting in low purity and limited yield. Yuan Liang et al. studied that the preparation of 5-HMF from hexose is currently the most effective way, and high-yield 5-HMF is mostly obtained by dehydrating raw materials such as fructose and glucose under the action of catalysts (solid acid, resin, inorganic acid enzyme, various metal salts and molecular sieves). In the reaction process, byproducts such as polymer humin and hydration products such as formic acid and levulinic acid are also formed. Its disadvantages are that various factors such as the selection of raw materials, catalyst type, solvent system, etc. will have a significant impact on the experimental results. In recent years, more and more researchers tend to hydrolyze cellulose into glucose to further prepare 5-HMF. DUMESIC et al. found that the reaction of glucose dehydration to prepare 5-HMF needs to go through two stages. Using HCl catalyst in a two-phase system consisting of water and organic phase, 5-HMF can be generated in the aqueous phase. The timely extraction of the obtained product into the organic phase will help reduce the probability of side reactions between 5-HMF and water and improve the yield and selectivity of HMF. At the same time, by adding inorganic salts such as NaCl to the aqueous phase, the extraction ability of inorganic salts for 5-HMF can be improved. However, the green and efficient preparation of 5-HMF from glucose still faces huge challenges, and it is particularly important to find other in situ isomerization catalysts. At present, the patented method for preparing 5-hydroxymethylfurfural CN201911328766.1, the preparation method disclosed in the invention directly mixes a hexose compound, an ionic liquid and an acidic catalyst to obtain a mixture, and vacuumizes the water during the reaction to obtain 5-hydroxymethylfurfural. This method uses an ionic liquid as a solvent to prepare HMF under mild conditions. In this invention, due to the low reaction temperature, basically no side reactions occur, and the solution after the reaction is clear and transparent. However, it has not yet been used in food. Patent: A method for preparing 5-hydroxymethylfurfural using microalgae as raw materials CN201510520140.6 uses microalgae, an environmentally friendly renewable biomass resource, to obtain a high value-added platform compound 5-hydroxymethylfurfural, thereby achieving CO 2 Through efficient biological fixation and catalytic conversion of microalgae, the hydrolysis and dehydration reaction conditions are mild, the process is simple, the raw material conversion rate is high, the selectivity for the target product 5-hydroxymethylfurfural is good, and the catalyst can be regenerated after simple solid-liquid separation. However, it is mainly used in industry.

[0005] Fermented Lactobacillus mucilaginosus is a Gram-positive rod-shaped bacterium with multiple characteristics, including the ability to grow under low pH conditions, an optimal growth temperature of 30-40°C, and the ability to use glucose and other monosaccharides and disaccharides to produce metabolites such as lactic acid. It is often used to make fermented Lactobacillus mucilaginosus beverages, yogurt and other dairy products, and can be added to other foods as a probiotic to increase their nutritional value, with a very broad prospect for industrial application.

[0006] Although there are many methods for synthesizing 5-hydroxymethylfurfural, there are many shortcomings in practical applications. From the perspective of environmental protection and health, the current synthesis method has low production safety and heavy environmental pollution. From the perspective of application fields, the application range in food is small, especially in rice products. At present, 5-hydroxymethylfurfural belongs to chemical raw materials and cannot be directly added in food production. How to safely apply 5-hydroxymethylfurfural to food is also urgently needed. Summary of the invention

[0007] In view of the above problems, the present invention provides a fermented Lactobacillus mucilaginosus INM3119 capable of improving the content and flavor of 5-hydroxymethylfurfural, and a preparation method and application thereof.

[0008] The purpose of the invention is achieved through the following scheme: a strain of fermented mucus lactobacillus, fermented mucus lactobacillus (Limosilactobacillus fermentum) INM3119, which was deposited in Guangdong Provincial Microbiological Culture Collection Center on August 13, 2024, with the deposit number: GDMCC NO: 65005, and the deposit address: 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou City, Guangdong Province.

[0009] Furthermore, the colony characteristics of Limosilactobacillus fermentum are as follows: after culturing on solid MRS plate medium for 48 hours, the colony diameter reaches 1 to 3 mm, the colony is milky white, round, flat, with a smooth surface and neat colony edges.

[0010] A kind of preparation method of fermented mucus lactobacillus

[0011] Step 1: Isolation of fermented mucus Lactobacillus: Isolate and screen fermented mucus Lactobacillus from yogurt samples, add the dairy product into a slurry, add it to sterile water, and dilute it to a concentration of 10 5 -10 6 , the dairy products of different dilution concentrations were evenly spread on the solid MRS medium, and then placed in an incubator at 37°C for 48 hours. Then, white colonies were selected on the solid MRS medium, and the fermentation mucus lactobacilli with the morphology were screened;

[0012] Step 2: Screening of fermented mucus lactobacillus: The fermented mucus lactobacillus was cultured to the logarithmic growth phase, and then inoculated with 1% of the strain, and the final concentration of the strain was 1×10 6 cfu / mL, inoculated into modified MRS medium, placed at 37℃ for 3 days to obtain the fermentation broth, and the 5-hydroxymethylfurfural content was detected.

[0013] Furthermore, the formula of the improved MRS medium is: weigh 10g of peptone, 8g of beef extract powder, 4g of yeast extract powder, 10g of Luo Han juice, 2g of dipotassium hydrogen phosphate, 2g of diammonium hydrogen citrate, 5g of sodium acetate, 0.2g of magnesium sulfate, 0.04g of manganese sulfate, and 1g of Tween 80, dissolve in 1000mL of distilled water, and sterilize at 0.1MPa and 121°C for 15min.

[0014] An application of fermented mucus lactobacillus is characterized in that 4g of monk fruit juice is added to 100ml of water, and 1g of fermented mucus lactobacillus is inoculated, and the mixture is fermented at 32°C for 24h, and the content of 5-hydroxymethylfurfural in the fermented liquid is detected after inactivation, and the obtained fermented liquid is used for cooking rice.

[0015] An application of fermenting mucus lactobacillus to increase the content of 5-hydroxymethylfurfural.

[0016] The invention discloses an application of fermented mucus lactobacillus in rice cooking to extend the shelf life of rice.

[0017] Advantages of the present invention: 1. The screening method of the fermented Lactobacillus mucilaginosus INM3119 of the present invention is universal and can be widely used in the screening of strains for 5-hydroxymethylfurfural content and flavor.

[0018] 2. The fermented mucus Lactobacillus INM3119 provided by the present invention can increase the 5-hydroxymethylfurfural content and flavor in monk fruit juice, and can be used for rice cooking in the later stage, which can effectively improve the product flavor and extend its shelf life. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The figure is a flowchart of the screening.

[0020] Figure 2 This is a morphological observation diagram of the fermentation culture medium of Lactobacillus mucilaginosus.

[0021] Figure 3 This is a picture of fermented mucus Lactobacillus observed under a microscope after Gram staining.

[0022] Figure 4 The inoculum concentration was 1.0×10 7 Total ion chromatogram of 5-hydroxymethylfurfural fermented by CFU / mL Lactobacillus mucilaginosus. DETAILED DESCRIPTION

[0023] The present invention will be further described below in conjunction with specific embodiments:

[0024] Unless otherwise specified, the experimental methods used in the following embodiments are all conventional methods; the materials, reagents, etc. used, unless otherwise specified, can be obtained from commercial channels.

[0025] Example 1, see attached Figure 1-3 , a strain of fermented mucus lactobacillus, fermented mucus lactobacillus (Limosilactobacillus fermentum) INM3119, which was deposited in Guangdong Provincial Microbiological Culture Collection Center on August 13, 2024, with the deposit number: GDMCC NO: 65005, and the deposit address: 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou City, Guangdong Province.

[0026] Furthermore, the colony characteristics of Limosilactobacillus fermentum are as follows: after culturing on solid MRS plate medium for 48 hours, the colony diameter reaches 1 to 3 mm, the colony is milky white, round, flat, with a smooth surface and neat colony edges.

[0027] A kind of preparation method of fermented mucus lactobacillus

[0028] Step 1: Isolation of fermented mucus Lactobacillus: Isolate and screen fermented mucus Lactobacillus from yogurt samples, add the dairy product into a slurry, add it to sterile water, and dilute it to a concentration of 10 5 -10 6 , the dairy products of different dilution concentrations were evenly spread on the solid MRS medium, and then placed in an incubator at 37°C for 48 hours. Then, white colonies were selected on the solid MRS medium, and the fermentation mucus lactobacilli with the morphology were screened;

[0029] Step 2: Screening of fermented mucus lactobacillus: The fermented mucus lactobacillus was cultured to the logarithmic growth phase, and then inoculated with 1% of the strain, and the final concentration of the strain was 1×10 6 cfu / mL, inoculated into modified MRS medium, placed at 37℃ for 3 days to obtain the fermentation broth, and the 5-hydroxymethylfurfural content was detected.

[0030] Furthermore, the formula of the improved MRS medium is: weigh 10g of peptone, 8g of beef extract powder, 4g of yeast extract powder, 10g of Luo Han juice, 2g of dipotassium hydrogen phosphate, 2g of diammonium hydrogen citrate, 5g of sodium acetate, 0.2g of magnesium sulfate, 0.04g of manganese sulfate, and 1g of Tween 80, dissolve in 1000mL of distilled water, and sterilize at 0.1MPa and 121°C for 15min.

[0031] An application of fermented mucus lactobacillus is characterized in that 4g of monk fruit juice is added to 100ml of water, and 1g of fermented mucus lactobacillus is inoculated, and the mixture is fermented at 32°C for 24h, and the content of 5-hydroxymethylfurfural in the fermented liquid is detected after inactivation, and the obtained fermented liquid is used for cooking rice.

[0032] An application of fermenting mucus lactobacillus to increase the content of 5-hydroxymethylfurfural.

[0033] The invention discloses an application of fermented mucus lactobacillus in rice cooking to extend the shelf life of rice.

[0034] A preparation method of fermented mucus lactobacillus,

[0035] 1. Processing of raw materials

[0036] Take a yogurt sample and dilute it to 10 with sterile saline. -1 , 10 -2 , 10 -3 , 10 -4 , 10 -5 , 10 -6 Concentration, make bacterial dilutions, take 0.1mL from each concentration dilution and evenly spread it on a solid MRS (containing 0.015% bromocresol purple) medium plate, culture at 37℃ for 48h, select colonies that are milky white, round, flat, with a smooth surface and neat colony edges. Streak the colonies on the solid MRS medium base for secondary purification, culture at 37℃ for 48h, pick single colonies for glycerol storage, and name them XJ0701 to XJ0709. The screening process is as follows Figure 1 shown.

[0037] 2. Preliminary screening of bacterial strains

[0038] The 9 strains were inoculated into MRS liquid medium at 1% inoculum and cultured at 37°C for 24 h. Then, they were inoculated into modified MRS medium at 1% inoculum and cultured at 37°C for 24 h. The final cell density reached 10 6 cfu / mL.

[0039] After 24 hours of fermentation, samples were taken from each tube and centrifuged at 10000 r / min for 10 minutes to obtain the supernatant, which was the sample for physical and chemical index testing. The results are shown in Table 1.

[0040] 5-Hydroxymethylfurfural gas phase detection: DB-WAX (30m, 0.25mm, 0.25μm) capillary column was selected. GC conditions were: helium as carrier gas, carrier gas flow rate was set to 1mL / min, non-split injection, and injection port temperature was 250℃. MS conditions were: ion source temperature 230℃, MS quadrupole temperature 150℃, electron energy 70eV, mass spectrometry scanning range 45-500, and scanning mode was full scan. The column box heating program was: 40℃ for 2min, increased to 150℃ at 3℃ / min, and then increased to 220℃ at 20℃ / min, and maintained for 1min. The mass spectrometry database method was used to identify the compound, and each peak was compared with the NISTLibrary mass spectrometry database by computer. The material matching degree greater than 800 was used as the qualitative basis.

[0041] Table 1 Analysis of 5-hydroxymethylfurfural produced by fermentation

[0042] Strain name pH <![CDATA[OD 600 ]]> 5-Hydroxymethylfurfural(μg / L) XJ0701 4.87 0.523 813.65 XJ0702 4.90 0.546 512.24 XJ0703 4.88 0.512 795.23 XJ0704 5.23 0.204 617.62 XJ0705 5.67 0.380 456.71 XJ0706 4.84 0.536 358.92 XJ0707 5.10 0.292 420.70 XJ0708 4.83 0.454 789.26 XJ0709 5.01 0.298 714.44

[0043] Strains XJ0701, XJ0703 and XJ0708 with lower pH and higher 5-hydroxymethylfurfural content were selected for rescreening.

[0044] 3. Strain rescreening

[0045] The lactic acid bacteria strains XJ0701, XJ0703, and XJ0708 selected in the initial screening were reactivated and cultured at a bacterial concentration of 10 6 cfu / mL The medium seed was prepared according to the national standard GB / T14612-2008 method, and the fermentation liquid was obtained by adding it to monk fruit juice, and then made into rice for sensory evaluation. The results are shown in Table 2

[0046] Table 2 Sensory analysis of rice

[0047] Species name Appearance taste Average score XJ0701 4.7 4.6 4.7 XJ0703 4.8 4.3 4.55 XJ0708 4.9 4.5 4.65

[0048] Note: The maximum score for each indicator is 5 points, and the higher the score, the better the result.

[0049] From the results in Table 2, we can see that XJ0701 has the best sensory evaluation result. As the target strain for rescreening, the morphological observation of this strain on the solid MRS plate medium is as follows: Figure 2 As shown, the colony diameter is 1-3 mm, the colony is milky white, round, flat, with a smooth surface and neat colony edges.

[0050] After Gram staining, the results were observed under a microscope. Figure 3 shown.

[0051] The XJ0701 obtained by the above screening was subjected to 16SrDNA sequencing and identification. After comparative analysis, the 16S region sequence obtained from the strain of the present invention was 99.86% similar to that of Limosilactobacillus fermentum. It can be determined that the strain is a fermentation strain of Lactobacillus fermentum INM3119, which was deposited in the Guangdong Provincial Microbial Strains and Lactobacillus fermentum on August 13, 2024. It can be used in the food fermentation industry and is named as the Collection Center. The collection number is: GDMCC No65005. Therefore, INM3119 and XJ0701 in this application refer to the same strain. The XJ0701 strain of the present invention has been genetically identified, and its gene sequence is as follows:

[0052] GGCTCAGGATGAACGCCGGCGGTGTGCCTAATACATGCAAGTCGAACGCGTTGGCCCAATTGA

[0053] TTGATGGTGCTTGCACCTGATTGATTTTGGTCGCCAACGAGGTGGCGGACGGGTGAGTAACACG

[0054] TAGGTAACCTGCCCAGAAGCGGGGGACAACATTTGGAAACAGATGCTAATACCGCATAACAAC

[0055] GTTGTTCGCATGAACAACGCTTAAAAGATGGCTTCTCGCTATCACTTCTGGATGGACCTGCGG

[0056] TGCATTAGCTTGTTGGTGGGGTAACGGCCTACCAAGGCGATGATGCATAGCCGAGTTGAGAGA

[0057] CTGATCGGCCACAATGGGACTGAGACACGGCCCATACTCCTACGGGAGGCAGCAGTAGGGAAT

[0058] CTTCCACAATGGGCGCAAGCCTGATGGAGCAACACCGCGTGAGTGAAGAAGGGTTTCGGCTCG

[0059] TAAAGCTCTGTTGTTAAAGAAGAACACGTATGAGAGTAACTGTTCATACGTTGACGGTATTTA

[0060] ACCAGAAAGTCACGGCTAACTACGTGCCAGCAGCCGCGGTAATACGTAGGTGGCAAGCGTTAT

[0061] CCGGATTTATTGGGCGTAAAGAGAGTGCAGGCGGTTTTCTAAGTCTGATGTGAAAGCCTTCGG

[0062] CTTAACCGGAGAAGTGCATCGGAAACTGGATAACTTGAGTGCAGAAGAGGGTAGTGGAACTCC

[0063] ATGTGTAGCGGTGGAATGCGTAGATATATGGAAGAACACCAGTGGCGAAGGCGGCTACCTGGT

[0064] CTGCAACTGACGCTGAGACTCGAAAGCATGGGTAGCGAACAGGATTAGATACCCTGGTAGTCC

[0065] ATGCCGTAAACGATGAGTGCTAGGTGTTGGAGGGTTTCCGCCCTTCAGTGCCGGAGCTAACGC

[0066] ATTAAGCACTCCGCCTGGGGAGTACGACCGCAAGGTTGAAACTCAAAGGAATTGACGGGGGCC

[0067] CGCACAAGCGGTGGAGCATGTGGTTTAATTCGAAGCTACGCGAAGAACCTTACCAGGTCTTGA

[0068] CATCTTGCGCCAACCCTAGAGATAGGGCGTTTCCTTCGGGAACGCAATGACAGGTGGTGCATG

[0069] GTCGTCGTCAGCTCGTGTCGTGAGATGTTGGGTTAAGTCCCGCAACGAGCGCAACCCTTGTTA

[0070] CTAGTTGCCAGCATTAAGTTGGGCACTCTAGTGAGACTGCCGGTGACAAACCGGAGGAAGGTG

[0071] GGGACGACGTCAGATCATCATGCCCCTTATGACCTGGGCTACACACGTGCTACAATGGACGGT

[0072] ACAACGAGTCGCGAACTCGCGAGGGCAAGCAAATCTCTTAAAACCGTTCTCAGTTCGGACTGC

[0073] AGGCTGCAACTCGCCTGCACGAAGTCGGAATCGCTAGTAATCGCGGATCAGCATGCCGCGGTG

[0074] AATACGTTCCCGGGCCTTGTACACACCGCCCGTCACACCATGAGAGTTTGTAACACCCAAAGT

[0075] CGGTGGGGTAACCTTTTA

[0076] Example 2 Genetic stability test of fermented Lactobacillus mucilaginosus INM3119

[0077] The fermented mucus Lactobacillus INM3119 in Example 1 was continuously propagated for 10 generations on the modified MRS liquid medium, and the 1st, 5th and 10th generation samples were centrifuged at 10,000 r / min for 10 min, and the supernatant obtained was the sample, which was tested for physical and chemical indicators. The method for detecting the content of 5-hydroxymethylfurfural was referenced to Example 1. At the same time, sensory evaluation was performed to determine its stability of propagation, and the specific data are shown in Table 3.

[0078] Table 3 Results of the stability test for passage

[0079] Number of generations 5-Hydroxymethylfurfural(μg / L) Rice sensory INM3119 1st Generation 813.5±0.26 4.8 INM3119 5th generation 811.5±0.30 5.0 INM3119 10th generation 814.2±0.38 4.9

[0080] The results in Table 3 show that the fermentation performance of Lactobacillus mucilaginosus INM3119 of different generations is normal, the content of 5-hydroxymethylfurfural varies within 10%, the strain has good genetic stability and meets the requirements for production and use.

[0081] Example 35 - Application of hydroxymethylfurfural monk fruit juice fermentation liquid in rice cooking

[0082] Rice cooking method: fermented mucus lactobacillus INM3119 was inoculated into monk fruit juice, and the inoculation fermentation bacteria concentration was 10 4 -10 8CFU / mL, 100 mL of water was added, and the mixture was fermented at 32°C for 24 h, inactivated, and fermented liquid was obtained. 30% of the fermented liquid was added to the rice for cooking. The method for detecting the content of 5-hydroxymethylfurfural in the fermented liquid was as described in Example 1. The content of 5-hydroxymethylfurfural in the rice was first added with pure water, boiled, cooled, and filtered. The detection method was as described in Example 1. The results are shown in Table 4. The sensory evaluation of the rice is shown in Table 5.

[0083] Table 4 5-HMF content in fermentation broth and rice

[0084]

[0085] Table 5 Sensory evaluation results of rice

[0086] Grouping Inoculation volume cfu / mL Appearance taste Taste Overall Rating Experimental Group 1 <![CDATA[1.0×10 4 ]]> 6.9 6.8 8.2 21.9 Experimental Group 2 <![CDATA[1.0×10 5 ]]> 7.5 8.4 7.1 23.0 Experimental Group 3 <![CDATA[1.0×10 6 ]]> 8.1 7.8 8.6 24.5 Experimental Group 4 <![CDATA[1.0×10 7 ]]> 9.6 9.4 9.0 28.0 Experimental Group 5 <![CDATA[1.0×10 8 ]]> 8.6 8.0 8.5 25.1

[0087] Note: Each item has a full score of 10 points, with a scoring interval of 0.1, and the comprehensive score is the sum of the values ​​of each item.

[0088] From the results in Tables 4 and 5, it can be seen that fermenting Lactobacillus mucilaginosus INM3119 in the fermentation broth can significantly increase the content of 5-HMF in monk fruit juice, and the more the inoculation amount, the higher the content of 5-HMF; however, too high or too low inoculation concentration of Lactobacillus mucilaginosus INM3119 will affect the appearance, taste and mouthfeel of rice. The most suitable inoculation concentration is 1.0×10 7 CFU / mL, and its test results are as follows Figure 4 This concentration can provide a higher 5-hydroxymethylfurfural content and improve the flavor of rice.

[0089] Example 4 Test of different rice shelf life

[0090] The rice prepared from the experimental group 4 and the control group (unfermented monk fruit juice) in Example 3 was used for shelf life detection, and the rice category was rice, black rice included black rice, polished rice, polished glutinous rice, and quinoa rice included rice and quinoa. The detection method was to place the product in a 2-6°C constant temperature box and detect the physical and chemical indicators and microbial indicators of the product every day. The moisture content is tested according to the first method of GB5009.3-2016, the acid value is tested according to the second method of GB 5009.229-2016, the peroxide value is tested according to the first method of GB5009.227-2023, the total colony count is tested according to GB 4789.2-2022, the coliform group is tested according to the second method of GB 4789.3-2016, the salmonella is tested according to GB 4789.4-2016, the Staphylococcus aureus is tested according to the second method of GB 4789.10-2016, the monocytogenes Listeria is tested according to the first method of GB 4789.30-2016, and the technical requirements are tested according to QZYM 0002S. The specific results are shown in Table 6 for the shelf life test of rice, Table 7 for the shelf life test of black rice, and Table 8 for the shelf life test of quinoa rice;

[0091] Table 6 Test results of rice shelf life

[0092]

[0093] Table 7 Black rice shelf life test results

[0094]

[0095] Table 8 Test results of shelf life of quinoa rice

[0096]

[0097] From the results of Table 6, Table 7, and Table 8, it can be seen that after fermented mucus lactobacillus INM3119 is inoculated in monk fruit juice for rice cooking, the storage time of rice at 2-6°C can be extended. From the physical and chemical properties, the moisture content of rice decreases during storage, the acid value and peroxide value indicators do not change much, the total colony count gradually increases during storage, the number of coliform bacteria does not change much, and Salmonella, Staphylococcus aureus and Listeria monocytogenes are all within the standard. Compared with the control group, the shelf life of rice in the experimental group is 5 days, and that in the control group is 3 days, indicating that fermented mucus lactobacillus INM3119 can extend the shelf life of rice after being used for rice cooking.

[0098] Based on the results of the above embodiments, the fermented mucus Lactobacillus INM3119 provided by the present invention is applied to rice cooking. On the basis of not changing the existing process, the 5-hydroxymethylfurfural content in the fermented broth of monk fruit juice can be significantly increased, and the aroma and taste of the rice product can be improved, and the shelf life of the rice product can be extended.

[0099] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. A fermentative Lactobacillus mucilaginosus, characterized in that: Limosilactobacillusfermentum INM3119, the strain was deposited in Guangdong Provincial Microbiological Culture Collection Center on August 13, 2024, with the deposit number: GDMCC NO: 65005, and the deposit address: 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou City, Guangdong Province.

2. A fermented mucus lactobacillus according to claim 1, characterized in that: The colony characteristics of Limosilactobacillus fermentum are as follows: after culturing on solid MRS plate medium for 48 hours, the colony diameter reaches 1 to 3 mm, the colonies are milky white, round, flat, with a smooth surface and neat colony edges.

3. A method for preparing the fermented mucus lactobacillus according to claim 1, characterized in that: Step 1: Isolation of fermented mucus Lactobacillus: Isolate and screen fermented mucus Lactobacillus from yogurt samples, add the dairy product into a slurry, add it to sterile water, and dilute it to a concentration of 10 5 -10 6 , the dairy products of different dilution concentrations were evenly spread on the solid MRS medium, and then placed in an incubator at 37°C for 48 hours. Then, white colonies were selected on the solid MRS medium, and the fermentation mucus lactobacilli with the morphology were screened; Step 2: Screening of fermented mucus lactobacillus: The fermented mucus lactobacillus was cultured to the logarithmic growth phase, and then inoculated with 1% of the strain, and the final concentration of the strain was 1×10 6 cfu / mL, inoculated into modified MRS medium, placed at 37℃ for 3 days to obtain the fermentation broth, and the 5-hydroxymethylfurfural content was detected.

4. A method for preparing a fermented mucus lactobacillus according to claim 3, characterized in that: The formula of the improved MRS medium is as follows: weigh 10g of peptone, 8g of beef extract powder, 4g of yeast extract powder, 10g of Luo Han juice, 2g of dipotassium hydrogen phosphate, 2g of diammonium hydrogen citrate, 5g of sodium acetate, 0.2g of magnesium sulfate, 0.04g of manganese sulfate, and 1g of Tween 80, dissolve in 1000mL of distilled water, and sterilize at 0.1MPa and 121℃ for 15min.

5. An application of the fermented mucus lactobacillus according to claim 1, characterized in that: 4 g of monk fruit juice was added to 100 ml of water, and 1 g of fermented mucus lactobacillus was inoculated, and the mixture was fermented at 32° C. for 24 h. After inactivation, the content of 5-hydroxymethylfurfural in the fermentation liquid was detected, and the obtained fermentation liquid was used for cooking rice.

6. A use of the fermented mucus lactobacillus according to claim 1 to increase the content of 5-hydroxymethylfurfural.

7. Use of the fermented mucus lactobacillus according to claim 1 in cooking rice to extend its shelf life.

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