CN114921377A

CN114921377A - Weissella greek, screening method and application thereof

Info

Publication number: CN114921377A
Application number: CN202210616743.6A
Authority: CN
Inventors: 王斌; 苟中军; 邹滢; 杜江; 黄巧; 杨光; 肖�琳
Original assignee: Juhui Food Technology Chongqing Co ltd
Current assignee: Juhui Food Technology Chongqing Co ltd
Priority date: 2022-06-01
Filing date: 2022-06-01
Publication date: 2022-08-19
Anticipated expiration: 2042-06-01
Also published as: CN114921377B

Abstract

The Weissella Greek is a Weissella Greek (Weissella hellenicai L-1) strain which is screened from pickled pickles, and the Weissella Greek (Weissella hellenicai L-1) strain is used for preparing fermented products of vegetables such as purple sweet potato fermented products and kelp fermented products. The Weissella Greek L-1 provided by the invention can produce lactic acid with high yield, can tolerate the acid environment of 50g/L NaCl and pH 2 to the maximum extent, can effectively utilize the inherent ingredients of food, improves the total acid content in the fermented product, enables the product to have strong acid note and excellent color, and meets the requirements of consumers on the fermented food.

Description

Weissella greek, screening method and application thereof

Technical Field

The invention belongs to the technical field of microorganisms, and particularly relates to Weissella Greek, a screening method and application thereof.

Background

The vegetarian food in the southwest region has the tradition of edible fermented food and contains rich probiotic resources, but the probiotic resources in the southwest region are unclear at the bottom, and the research on mining and basic characteristics is insufficient, so that the development bottleneck of the fermented food industry in the southwest region is limited. The flavor of the fermented food is an important factor influencing the sensory quality and the consumer acceptance of the product, the pleasant flavor of the traditional pickled vegetables in the southwest region is obtained from the fermentation of the heterotypic lactic acid bacteria and the fermentation of the homotypic lactic acid bacteria, the heterotypic lactic acid bacteria rapidly generate a large amount of flavor substances such as acetic acid, ethanol, mannitol and the like in the initial stage of the fermentation, and the homotypic lactic acid bacteria can replace the heterotypic lactic acid bacteria to generate a large amount of acid along with the fermentation, so that the final product has a very sour and refreshing feeling, and the two are fermented in a synergistic manner to form the unique flavor. The fermentation bacteria in the traditional pickles in the southwest region are researched and used for rapid fermentation in fermented foods, and the method has wide application prospect in deep research on flavor characteristics, tolerance and the like of the fermented foods to obtain high-quality products.

Purple sweet potato (Ipomoea batatas L.) is an edible root, belonging to the family Convolvulaceae. The purple sweet potato with dark color is a highly acylated anthocyanin which takes anthocyanin or paeoniflorin as aglycone, and is a natural pigment which is very beneficial to health. A large amount of anthocyanin and phenolic substances in purple sweet potatoes have physiological activities of resisting oxidation, resisting cancer, resisting inflammation, resisting hyperglycemia and the like. In addition, the purple sweet potato also contains 18% of purple sweet potato starch, about 5% of sugar, about 2% of protein, dietary fiber, vitamins (C, B1, B2 and E), mineral substances (potassium, calcium, magnesium and zinc) and other nutrient components, and iodine and selenium are more than 20 times of those of common sweet potatoes. Therefore, the purple sweet potato is a good name of life-prolonging food, and is a green and healthy food raw material. However, in the prior art, the purple sweet potatoes have the problems of easy color change, easy taste change, poor taste and the like in the processing process.

Kelp is rich in chemical components and bioactive substances, and has been used in many industrial fields such as food, feed, and prodrugs. Research shows that the kelp contains rich fucoidan, which is divided into 3 substances of algin, algin starch and fucoidan, wherein the proportion of the algin is 15-25%, and the application value of the kelp in the reprocessing process of functional foods and partial medicines is very high. In addition, the kelp also contains abundant alginic acid, vitamins, mineral substances and various trace elements, and has very abundant delicate flavor due to the free glutamic acid. At present, the cultivation technology of the kelp in China is quite mature, but the processing and utilization of the kelp are still in a primary stage, the products mainly comprise salted kelp, light dried kelp and instant seasoning kelp, the kelp deep processing industry is innovatively developed, healthy and nutritional kelp processing products are researched and developed, the requirements of health Chinese strategies in 2030 of China are met, the additional value of the kelp can be increased, and the sustainable development of the kelp industry chain is promoted.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides Weissella Greek, a screening method and application thereof, the obtained Weissella Greek produces acid quickly and produces lactic acid with high yield, and the screened Weissella Greek is applied to fermented food, so that the fermented food has the characteristics of soft acidity, full flavor, good color and luster and the like.

The technical problem to be solved by the invention is realized by adopting the following technical scheme:

the first purpose of the invention is to provide Weissella Greek, which is characterized in that the Weissella Greek is Weissella Greek (Weissella helllerniai L-1) and is preserved in China center for type culture collection, the address is Wuchang Lodojia mountain in Wuhan city, Hubei China, the preservation number is CCTCC M2022425, and the preservation time is 19 days at 4 months in 2022 years.

Further, the 16S rDNA sequence of the Welsh-Greek bacterium (Weissella hellernica L-1) is shown in SEQ ID NO. 3.

The second purpose of the invention is to provide a screening method of Weissella Greek, which is characterized by comprising the following steps:

s1, weighing a pickled Chinese cabbage sample in the southwest region, putting the pickled Chinese cabbage sample into a test tube containing sterile deionized water, and fully oscillating to form a mother suspension; preparing the mother suspension to 10 ^-1 、10 ^-2 、10 ^-3 、10 ^-4 、10 ^-5 Deionized water gradient diluent for later use; coating each gradient diluent on an MRS solid culture medium respectively, culturing for 48h at 35 ℃, and separating and purifying to obtain separated strains;

s2, inoculating the separated strain obtained from S1 into an MRS liquid culture medium, and culturing at 35 ℃ and 80rpm for 18h to obtain seed liquid;

s3, inoculating the seed liquid obtained in the step S2 into an MRS liquid culture medium according to the inoculation amount of 1%, and culturing at 35 ℃ and 80rpm for 24h to obtain the Weissella Shewanela Hellenicai L-1 strain.

Furthermore, the Weissella greek (Weissella hellerinica L-1) strain can endure an acid environment with 50g/L NaCl and pH 2, so that the Weissella greek strain can be effectively colonized in the pickled vegetables to start vegetable fermentation, quick acid production is realized, the acid production rate is increased, quick start of vegetable fermentation is realized, and vegetable fermented products are obtained.

The third purpose of the invention is to provide the application of the Weissella Greek (Weissella hellerinica L-1) strain in the vegetable fermentation products.

Further, the vegetable fermentation product comprises a purple sweet potato fermentation product and a kelp fermentation product.

Further, the purple sweet potato fermented product is purple sweet potato fermented sauce.

Further, the kelp fermentation product is kelp vegetable juice.

The fourth purpose of the invention is to provide a purple sweet potato fermented product taking the Welsh cereus (Weissella hellenenicai L-1) strain as a leavening agent, and the preparation method is characterized by comprising the following steps:

activating the Weissella Greek L-1 strain to obtain an activated strain; cleaning fresh purple sweet potatoes, cooking the fresh purple sweet potatoes and water according to the ratio of 1:1, performing constant volume pulping, filling the pulp into a sterilized triangular flask, inoculating the Weissella Sheessica L-1 strain activated strain according to the inoculation amount of 5% of the volume-mass ratio, and standing and fermenting at the temperature of 20-25 ℃ for 7 days to obtain the purple sweet potato fermented product.

Preferably, the fermentation temperature of the purple sweet potatoes is 21 ℃.

Further, the activation process is as follows: inoculating Weissella Greessica L-1 strain on MRS solid culture medium, activating and culturing at 35 deg.C for 24h, taking out thallus with toothpick, inoculating into 250mL triangular flask containing 100mL MRS liquid culture medium, culturing at 35 deg.C under 80r/min shaking table for 18h until bacterial liquid concentration reaches 10 ⁸ CFU/mL。

The fifth purpose of the invention is to provide a kelp fermentation product using the Weissella Greek (Weissella hellenenicai L-1) strain as a fermentation agent, which is characterized in that the preparation method comprises the following steps:

activating the Weissella Sheessica L-1 strain to obtain an activated strain; cleaning the selected kelp and vegetables, pulping the kelp and water in a ratio of 1:3, and pulping the vegetables and the water in a ratio of 1: 2; and (3) filling the pulped kelp liquid and vegetable liquid into a sterilized triangular flask, inoculating the Weissella Greek L-1 strain activated strain according to the inoculation amount of 2% of the volume mass ratio, and standing and fermenting at the temperature of 20-25 ℃ for 6 days to obtain the kelp fermented product.

Preferably, the fermentation temperature of the kelp is 21 ℃.

Further, the volume ratio of the kelp liquid and the vegetable liquid which are mixed before inoculation and subjected to pulping is 1: 3.

Further, the vegetable is cabbage.

Compared with the prior art, the invention has the beneficial technical effects that:

the Weissella sierra (Weissella hellerinica L-1) strain provided by the invention has remarkable lactic acid producing capability and can endow a product with unique and soft acid aroma. The bacterial strain can tolerate an acid environment of 50g/L NaCl and pH 2, has a high acid production rate, and can quickly start vegetable fermentation. The purple sweet potato fermented sauce prepared by fermentation is comprehensive in nutrition, thick in taste and high in additional value, the original color system of purple sweet potatoes is not changed, and released small molecular substances are more beneficial to digestion and absorption of a human body. The natural ingredients in the kelp and the cabbage are fully utilized to generate the organic acid, so that the product has the special sour note of lactobacillus fermentation, and the flavor is full and soft. The preparation process of the vegetable fermented product is simple, is beneficial to large-scale industrialization, does not add any essence, pigment and preservative, and is a safe food for lactobacillus fermented vegetables.

The pickled Chinese cabbage selected by the invention is pickled Chinese cabbage of common farmers in the southwest region, pickled Chinese cabbage sold in the southwest region and the like.

The above description is only an overview of the technical solutions of the present invention, and the present invention can be implemented in accordance with the content of the description so as to make the technical means of the present invention more clearly understood, and the above and other objects, features, and advantages of the present invention will be more clearly understood.

Drawings

FIG. 1 shows the colony morphology of Wessella Greek (Weissella helleronica L-1) strain in MRS solid medium.

FIG. 2 is a microscope image of the strain of Wessella Greek (Weissella hellernica L-1) of the present invention.

FIG. 3 is a graph showing salt concentration tolerance of strains of Wessella Greek (Weissella helleronica L-1) according to the present invention.

FIG. 4 is a graph showing the acid pH tolerance of strains of Wessella Greek (Weissella hellernica L-1) according to the present invention.

FIG. 5 is a graph showing the acid production rate of Wessella Greek (Weissella hellernica L-1) strain according to the present invention.

Detailed Description

The technical scheme of the invention is further explained in detail by combining the drawings and the specific embodiment. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.

In addition, unless otherwise specifically indicated, various starting materials, reagents, instruments and equipment used in the present invention may be commercially available or prepared by existing methods. In the quantitative experiments in the embodiments of the invention, three repeated experiments are set, and the results are averaged.

The improved MRS solid culture medium used in the embodiment of the invention comprises 10g of peptone, 5g of yeast extract, 10g of beef extract, 20g of glucose, 2g of dipotassium phosphate, 2g of ammonium citrate tribasic, 5g of sodium acetate, 801 mL of tween, 0.58g of magnesium sulfate heptahydrate, 0.25g of manganese sulfate tetrahydrate, 20g of agar, 10g of calcium carbonate, 0.1g of bromocresol purple, 1000mL of deionized water and pH of 6.2-6.4.

Example 1: separation, screening and identification of Weissella Sheessica L-1 strain

1.1 isolation of Wessella Greek L-1 Strain

The separation of the Weissella Sheessica L-1 strain comprises three steps of sampling, enrichment, primary screening and secondary screening, and specifically comprises the following steps:

1. sampling

The pickled Chinese sauerkraut sample is collected from peasants in southwest by using an ice box, is filled into a clean sampling bag, is marked, and is transported back to a laboratory to be stored in a refrigerator at 4 ℃ to serve as a sample.

2. Enrichment and prescreening

In a sterile super clean bench, 1.0g of a self-made pickled Chinese cabbage sample of farmhouse is weighed and placed into a test tube containing 9mL of sterile deionized water, and the mother suspension is prepared by fully shaking through vortex. The mother suspension was then prepared to 10 using deionized water ^-1 、 10 ^-2 、10 ^-3 、10 ^-4 、10 ^-5 Gradient deionized water diluent, coating 100 μ L of each gradient diluent on improved MRS solid agar culture medium, culturing at 35 deg.C for 48 hr, and dissolving calcium ringAfter streaking and purifying the strains with different forms, separated strains are obtained and stored in a refrigerator with the temperature of minus 80 ℃ by using 50 percent of glycerol for standby.

3. Double sieve

Inoculating the separated bacterial strain obtained by primary screening into an MRS liquid culture medium, culturing at 35 ℃ and 80rpm for 18h to prepare a seed solution, inoculating the seed solution into a triangular flask with the volume of 250mL containing 100mL of the MRS liquid culture medium according to the inoculation amount of 1%, culturing at 35 ℃ and 80rpm for 24h to obtain bacterial strains, sequentially naming the bacterial strains as a bacterial strain L-1, a bacterial strain M-2, a bacterial strain M-6, a bacterial strain L-3 and a bacterial strain L-7, determining the content of lactic acid in fermentation liquor of the bacterial strains separated from all pickled Chinese sauerkraut samples, and obtaining experimental results shown in table 1.

TABLE 1 comparison of lactic acid production

1.2 identification of the Strain

Performing a series of physiological and biochemical identification on the pure culture of the strain L-1 obtained by separation and purification, performing DNA extraction, amplifying and sequencing 16S rDNA, amplifying the 16S rDNA by using primers F27 and R1492,

the primer sequences are as follows:

f27:5'-AGAGTTGATCATGGCAG-3', shown as SEQ ID NO. 1;

r1492:5'-TAGGGTTACCTTGTTACGCTT-3', shown as SEQ ID NO.2

PCR amplification conditions of 95 deg.C for 5min, 94 deg.C for 30s, 55 deg.C for 30s, 72 deg.C for 90s, 30 cycles, 72 deg.C for 10min, and 4 deg.C for storage.

Sequencing the PCR amplification product, wherein the sequencing result is shown as SEQ ID NO. 3.

The strain L-1 is subjected to homology comparison, and is named as Weissella Greek (Weissella hellenenicai L-1) by combining morphological and physiological and biochemical characteristics of the strain L-1. The Weissella Sheessica L-1 strain separated and screened in this example was cultured on MRS solid medium and observed for colony morphology, and the strain was observed by microscopic image, and the observation results are shown in FIG. 1 and FIG. 2. Referring to FIG. 1, it can be seen that the Weissella Sheessica L-1 strain of the present invention forms white round, regular-edged, smooth-surfaced and opaque colonies on MRS solid medium.

Referring to FIG. 2, the strain of Wessella Greek L-1 was observed microscopically and microscopically revealed irregular short rods, paired or short chain arranged bacteria.

Meanwhile, physiological and biochemical characteristics of the Weissella Greek L-1 strain are tested, and the results are shown in the table 2:

TABLE 2 physiological and biochemical characteristics of Weissella Greek L-1 strains

Note: "+" indicates a positive reaction, presence or presence, "-" indicates a negative reaction, absence or absence.

The Weissella Greek obtained by the method is Weissella Greek (Weissella hellenicai L-1), is preserved in China center for type culture collection, is preserved in Wuchang Lojia mountain in Wuhan City, Hubei China, has the preservation number of CCTCC M2022425, and has the preservation time of 2022, 4 months and 19 days.

It can be seen that in this example, the method for screening strains of Weissella greek (Weissella hellenenica L-1) from typical farmhouse pickles in the southwest region employs a gradient concentration dilution method, coats the diluted sample liquid on an improved solid MRS plate, anaerobically cultures for 48h at 35 ℃, selects strains with different colonies and calcium-soluble rings, further streaks, separates and purifies to obtain isolated strains, then combines with lactic acid production capacity experiments to determine L-1 strains, and determines the strain species by sequence comparison. The L-1 strain has strong capacity of producing lactic acid, and the concentration of the lactic acid can reach 10.46 mg/L.

Example 2: the salt tolerance, acid tolerance and acid production capability of the Weissella Greek strain L-1 are detected by the Weissella Greek (Weissella hellenicai L-1) strain:

after the Weissella Greek strain L-1 is activated in an MRS liquid culture medium for 12 hours, the OD600 value of the bacterial liquid reaches 0.8. Inoculating the strain into a 250mL triangular flask containing 100mL MRS liquid culture medium with different NaCl mass concentrations (0, 10, 20, 30, 40, 50 and 60g/L) according to the inoculation amount of 1 percent respectively, taking the seed culture medium without inoculation as a blank control, setting 3 replicates in each group, carrying out shake culture at 35 ℃ and 80r/min for 48h, and then measuring the light absorption value of the culture solution at 600nm by using a spectrophotometer.

As shown in FIG. 3, the Greek Welsh strain L-1 has a wide salt tolerance, which can tolerate 50g/L NaCl at most, and the results show that the Greek Welsh strain L-1 has a high salt tolerance.

Acid resistance of Wessel Greek strain L-1:

activating the Weissella Greek strain L-1 in an MRS liquid culture medium for 12 hours until the OD600 value of the bacterial liquid reaches 0.8. The cells were inoculated into 250 mL-volume flasks containing 100mL of seed medium at different pH concentrations (1, 2, 3, 4, 5, 6, 7) at 1% inoculum size, 3 replicates of each group were set using the non-inoculated seed medium as a blank, and after incubation at 35 ℃ for 48h at 80r/min, the OD at 600nm of the culture was determined.

The results are shown in FIG. 4, the tolerance range of the acid pH of the strain L-1 is 2-7, and the maximum tolerance range of the acid pH is 2, which shows that the strain L-1 has good adaptability to a wide range of acid conditions.

Acid production capacity of Wessel Greek strain L-1:

a colony of a one-ring Greek Wessel strain L-1 is picked by using an aseptic inoculating ring, inoculated in an MRS liquid culture medium and activated for 12 hours, and the OD600 value of the bacterial liquid reaches 0.8. Inoculating the strains into 250mL triangular flasks containing 100mL of MRS liquid culture medium according to the inoculation amount of 1%, using the MRS liquid culture medium without inoculation as a blank control, setting three times for each group, performing shake culture at 35 ℃ and 80r/min for 24 hours, sampling every 3 hours, detecting the pH value of the culture solution by using a pH meter, and calculating the acid production rate of the strains, wherein the acid production rate is the initial pH of the culture medium-the pH of each time point.

The result is shown in fig. 5, the acid production capacity of the welsh strain L-1 is continuously enhanced with the increase of the fermentation time, when the fermentation liquid is cultured for 9 hours, the pH of the fermentation liquid reaches 4.40, the acid production rate reaches 1.99, the acid production rate of most lactic acid bacteria after the fermentation for 9 hours is 0.43-1.29 according to literature reports, the acid production rate of the screened welsh strain L-1 in the experiment is 1.99, which is obviously higher than the value, and the great advantage is obtained, which indicates that the acid production rate of the strain L-1 is very fast, and the characteristic plays an important role in subsequent fermentation.

Example 3 Welsh Sheeela hellernica L-1 strain as a starter for the preparation of purple sweet potato sauce

S1, inoculating the Weissella Greek L-1 strain on MRS solid culture medium, performing activated culture at 35 ℃ for 24h, taking thallus by using toothpick, inoculating the thallus into a 250mL triangular flask containing 100mL MRS liquid culture medium, performing shake culture at 35 ℃ and 80r/min for 18h until the concentration of bacterial liquid reaches 10 ⁸ CFU/mL to obtain activated strain of Weissella Sheessi L-1 strain for use;

s2, cleaning fresh purple sweet potatoes, cooking the fresh purple sweet potatoes with water in a ratio of 1:1, fixing the volume, pulping, filling the pulp into a sterilized triangular flask, inoculating a Weissella Shewanella L-1 strain activated strain in an inoculation amount of 5% by volume and mass, and standing and fermenting for 7 days at 20-25 ℃ (preferably 21 ℃) to obtain the purple sweet potato fermented sauce.

Sample test 1: referring to the food analysis manual compiled by Ningzhengxiang, the content of total acid in the purple sweet potato fermented sauce is determined by adopting a NaoH titration method, and the result is shown in a table 3, wherein the content of the total acid in the purple sweet potato sauce fermented by the Weissella Greessica (Weissella helleronica L-1) strain is 0.66%.

TABLE 3 analysis of total acid in purple sweet potato sauce fermented by Weissella Greek L-1 strain

Sample test 2: 1g of the fermentation sample was weighed and dissolved in 9mL of 80% ethanol. Sucking 0.5mL of the sample to be detected by a pipette, placing the sample into a 10mL colorimetric tube with a plug, adding 0.5mL of deionized water, shaking uniformly, adding 0.5mL of welan reagent, mixing uniformly, adding 1.5mL of 20% Na after 1min ₂ CO ₃ Mixing the solutions, diluting with deionized water to 10mL, heating in 70 deg.C constant temperature water bath for 10min, and coolingAfter cooling, the OD was measured in an ultraviolet spectrophotometer at 765 nm. The gallic acid is used as a standard substance for comparison, and the test result is shown in a table 4. The result shows that the total phenol content of the purple sweet potato sauce fermented by the Weissella Greek L-1 strain is 14.37mg of gallic acid/g of purple sweet potato sauce, which is 5 times of that of unfermented purple sweet potatoes.

TABLE 4 analysis of total phenols in Weissella Greek L-1 fermented purple sweet potato sauce

Sample test 3: measuring the color of the fermented purple sweet potatoes by using a Lovibond colorimeter, wherein the length of a cuvette is 10 mm. The result shows that the purple sweet potato sauce fermented by the Weissella Greek L-1 strain is reddish yellow, does not change the color system of the purple sweet potatoes and is basically close to the color of a control group.

TABLE 5 Weissella Sheeensis L-1 fermented purple sweet potato sauce color detection value

In conclusion, the purple sweet potato fermented sauce prepared by the method is appropriate in acidity and comprehensive in nutrition. The Weissella Greek L-1 strain can fully utilize inherent components of the purple sweet potato raw material to generate organic acid, so that the product has the unique sour note of lactic acid bacteria fermentation, the flavor is full and soft, the original color system of the purple sweet potato cannot be changed after the Weissella Greek L-1 strain ferments the purple sweet potato sauce, and the processing mode can not damage the nutritional components such as purple sweet potato anthocyanin and the like. Moreover, the total phenol content in the purple sweet potato fermented sauce is increased, which indicates that Weissella Shewanella L-1 can generate a specific enzyme system to break the insoluble substances of phenolic acid in the purple sweet potato esterified with carboxyl on a phenol ring or carboxyl on a molecular structure, and release the phenolic acid. The purple sweet potato fermented sauce prepared by fermentation is comprehensive in nutrition, thick in taste and high in added value, and released small molecular substances are more beneficial to digestion and absorption of a human body.

Example 4 preparation of kelp vegetable juice with Weissella Greek (Weissella hellernica L-1) Strain as leavening agent

S1, inoculating the Weissella Greek L-1 strain on an MRS solid culture medium, performing activated culture at 35 ℃ for 24h, taking the thallus by using a toothpick, inoculating the thallus into a 250mL triangular flask containing 100mL of MRS liquid culture medium, performing shake culture at 80r/min at the constant temperature of 35 ℃ for 18h until the concentration of the bacterial liquid reaches 10 ⁸ CFU/mL to obtain activated strain of Weissella Sheessi L-1 strain for use;

s2, removing the sample with scabs and rotten spots from the kelp and the cabbage, washing with tap water, pulping the kelp and the water in a ratio of 1:3, and pulping the cabbage and the water in a ratio of 1:2 for later use.

S3, filling the pulped kelp liquid and the cabbage liquid obtained in the step S2 into a sterilized triangular flask in a ratio of 1:3, inoculating a Weissella Greek L-1 strain activated strain with an inoculation amount of 2% by volume mass, and standing and fermenting for 6 days at 20-25 ℃ (preferably 21 ℃) to obtain a kelp vegetable juice fermented product.

Sample test 1: the total number of colonies was determined by reference to GB 4789.2-2016, and the pH was measured by a pH meter. Referring to table 6, the results show that the total number of colonies in the kelp vegetable juice after 6 days of fermentation of the welsh bacilli L-1 of the invention is increased to 7.38(lg (CFU/mL)), which indicates that the welsh bacilli L-1 can well metabolize organic matters in the kelp cabbage, and shows stronger growth capacity; the pH value of the kelp vegetable juice after the Weissella Greek L-1 is fermented for 6 days is reduced from 6.78 to 3.67, which shows that the Weissella Greek L-1 can utilize nutrient substances in the kelp cabbage liquid to grow and simultaneously generate acidic metabolic substances, so that the pH value of the environment is continuously reduced along with the fermentation.

TABLE 6 analysis of the total number of colonies and pH value in Weissella Greek L-1 fermented kelp vegetable juice

Sample test 2: centrifuging a kelp vegetable juice sample fermented by Weissella Greek L-1 for 6 days at 8000r/min for 15min, sucking supernatant, measuring total sugar content by adopting a phenol-sulfuric acid method, and measuring reducing sugar content by adopting a DNS method. Referring to Table 7, the results show that the total sugar in the kelp vegetable juice after 6 days of fermentation of the Weissella Greek L-1 of the invention is reduced from 40.49mg/mL to 33.79mg/mL, and the content of the reducing sugar is reduced from 16.69mg/mL to 14.46mg/mL, which indicates that the Weissella Greek L-1 can be well colonized in the kelp vegetable juice and can utilize the existing carbon sources in the kelp and the cabbage through fermentation.

TABLE 7 analysis of total sugar and reducing sugar in Weissella Greek L-1 fermented Laminaria japonica vegetable juice

In conclusion, the kelp vegetable juice prepared by the method of the embodiment is suitable for sour and sweet. The Weissella Sheessica L-1 strain can fully utilize inherent components in kelp and cabbage to generate organic acid, so that the product has the acid aroma peculiar to lactobacillus fermentation, and the flavor is full and soft.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

While the present invention has been described with reference to the particular illustrative embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various modifications, equivalent arrangements, and equivalents thereof, which may be made by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A Wessella-Greek, characterized in that: the Weissella Greek is Weissella Greek (Weissella hellerinica L-1), and is preserved in China center for type culture Collection with a preservation number of CCTCC M2022425.

2. The weissella-greek of claim 1, wherein: the 16S rDNA sequence of the Weissella Greek (Weissella hellerinica L-1) is shown in SEQ ID NO. 3.

3. A screening method of weissella-greek according to claim 1 or 2, characterized in that it comprises the following steps:

s1, weighing a pickled Chinese cabbage sample in the southwest region, placing the pickled Chinese cabbage sample into a test tube containing sterile deionized water, and fully oscillating to form a mother suspension; preparing the mother suspension to 10 ^-1 、10 ^-2 、10 ^-3 、10 ^-4 、10 ^-5 Deionized water gradient diluent for later use; respectively coating each gradient diluent on an MRS solid culture medium, culturing for 48 hours at 35 ℃, and separating and purifying to obtain separated strains;

4. The method for screening Welsh Greek bacteria of claim 3, wherein: the Weissella Greece (Weissella hellerinica L-1) strain can resist an acidic environment with 50g/L of NaCl and pH of 2, so that the Weissella Greece strain can be effectively colonized in pickled vegetables to start vegetable fermentation, quick acid production is realized, the acid production rate is increased, quick start of vegetable fermentation is realized, and a vegetable fermented product is obtained.

5. Use of a strain of Weissella Greek (Weissella hellenicai L-1) according to any one of claims 1 to 4 in a vegetable fermented product.

6. The use of claim 5, wherein: the vegetable fermentation product comprises a purple sweet potato fermentation product and a kelp fermentation product.

7. A fermented purple sweet potato product using Weissella Greek (Weissella hellerinica L-1) strain as a starter according to claim 6, wherein the preparation method comprises the following steps:

activating the Weissella Sheessica L-1 strain to obtain an activated strain; cleaning fresh purple sweet potatoes, cooking the fresh purple sweet potatoes and water according to the ratio of 1:1, performing constant volume pulping, filling the pulp into a sterilized triangular flask, inoculating the Weissella Sheessica L-1 strain activated strain according to the inoculation amount of 5% of the volume-mass ratio, and standing and fermenting at the temperature of 20-25 ℃ for 7 days to obtain the purple sweet potato fermented product.

8. A fermented purple sweet potato product using the Weissella greek (Weissella hellerinica L-1) strain as a starter as claimed in claim 7, wherein the activation process is: inoculating Weissella Greece L-1 strain on MRS solid culture medium, activating and culturing at 35 deg.C for 24h, taking out thallus with toothpick, inoculating in 250mL triangular flask containing 100mL MRS liquid culture medium, culturing at constant temperature of 35 deg.C for 18h at 80r/min by shaking table until bacterial liquid concentration reaches 10 ⁸ CFU/mL。

9. A fermented kelp product using the Welsh Greek fungus (Weissella helleniacai L-1) strain as a starter according to claim 6, wherein the preparation method comprises the following steps:

activating the Weissella Sheessica L-1 strain to obtain an activated strain; cleaning the selected kelp and vegetables, pulping the kelp and water in a ratio of 1:3, and pulping the vegetables and the water in a ratio of 1: 2; and (3) filling the pulped kelp liquid and vegetable liquid into a sterilized triangular flask, inoculating the Weissella Sheessica L-1 strain activated strain according to the inoculation amount of 2% of the volume mass ratio, and standing and fermenting at the temperature of 20-25 ℃ for 6 days to obtain the kelp fermented product.

10. A kelp fermentation product using said strain of welshilla greek (Weissella hellerinica L-1) as a starter according to claim 9, wherein: the volume ratio of the kelp liquid and the vegetable liquid which are mixed before inoculation and subjected to pulping is 1: 3.