CN114617242A

CN114617242A - Processing technology of black pickled vegetables and product thereof

Info

Publication number: CN114617242A
Application number: CN202210378459.XA
Authority: CN
Inventors: 蒋立文; 刘洋; 廖卢艳; 李跑; 覃业优; 王蓉蓉
Original assignee: Hunan Agricultural University
Current assignee: Hunan Agricultural University
Priority date: 2022-04-12
Filing date: 2022-04-12
Publication date: 2022-06-14
Anticipated expiration: 2042-04-12
Also published as: CN114617242B

Abstract

The invention discloses a processing technology of black pickled vegetables and a product thereof, and relates to the technical field of food processing. The invention discloses lactobacillus plantarum and application thereof in black pickled vegetable processing. The invention also discloses a processing technology of the black pickled vegetable, which comprises the following steps: (1) cleaning and cutting; (2) preserving heat and fermenting; (3) dehydrating; (4) drying; (5) complex enzyme treatment; (6) steaming under high pressure; (7) drying; (8) spreading and moisture regaining. The processing technology of the invention can overcome the quality difference caused by different raw materials, improve the content of the soluble dietary fiber, improve the taste, ensure the consistent quality and flavor of the product, ensure the product quality and promote the healthy development of the industry.

Description

Processing technology of black pickled vegetables and product thereof

Technical Field

The invention relates to the technical field of food processing, in particular to a processing technology of black pickled vegetables and a product thereof.

Background

China is the biggest world producing country of fruit and vegetable raw materials. The annual output of fruits and vegetables in China is 7 hundred million tons in 2020, which accounts for more than 40% of the total world output, and the fresh price of fruits and vegetables in China is the lowest globally. The cost of the fresh fruits and vegetables is only one tenth of the cost of the fresh fruits and vegetables in developed countries, and the rotting loss rate of the fresh fruits and vegetables in China is high. The fruit reaches 30 percent, the vegetable reaches 40 to 50 percent, and the loss rate of developed countries is less than 7 percent. The deep processing technology level of fruits and vegetables in China is low. The processing rate of fruits is lower than 10 percent, the processing rate of vegetables is less than 1 percent, and the difference is quite large compared with 40 to 70 percent of developed countries. The vegetable is one of large agricultural economic crops in China, is an important support for realizing the quality improvement and upgrading development of the Shaoxing agricultural industry, the comprehensive processing capacity of the vegetable in China is not systematic, and the fresh-keeping and processing technology system is incomplete, so that leaf vegetables except fresh food are treated as feed or garbage, the resource is greatly wasted, the quantity of vegetable raw material waste accounts for more than 30% every year, and the vegetable is one of important bottlenecks for restricting the high-quality development of agriculture in China.

The leaf vegetable has wide raw material source, high yield, low value, rich nutrition of vegetable leaves, a large amount of oligosaccharide, a small amount of protein, higher mineral elements and vitamins, but higher moisture content and easy rotting. The salted vegetables are food culture and are all accumulated in culture. Because farmers almost need to pickle every family, the farmer can eat the pickled Chinese cabbage, and the pickled Chinese cabbage is inherited in all generations in autumn. The grandma pickles, old pickled vegetables, black pickles and the like are leaf vegetable processing products, the processing means of each region are different, the taste and style of the products are different, and regional diet culture with different regional characteristics is formed.

The processing method of the leaf vegetables in China has a plurality of processing modes, and the finished products are generally prepared by withering fresh leaf vegetables, directly pickling the fresh leaf vegetables in high salt for maturity, desalting, cutting, slightly fermenting with lactic acid, seasoning and sterilizing. The second processing mode is that the vegetable leaves are dried in the sun or air, then rehydrated, cut up and put into a jar to be fermented with or without salt, so that a semi-finished product with the water content of 30-50% is formed, and the semi-finished product is fried to be a table food in the catering industry, such as grandma vegetables in Hunan, Hubei and Jiangxi; the third processing mode is that leaf vegetables are directly cut up for fermentation, and then the leaf vegetables are made into the preserved vegetable or the black pickled vegetable with the moisture content of about 10 percent, black and bright color and special fragrance through specific 'three-steaming three-sun-drying' or 'nine-steaming nine-sun-drying', and the preserved vegetable or the black pickled vegetable is mainly used as a main ingredient of the preserved pork with the preserved vegetables with characteristics in the south and is also popular among consumers.

The pickled black vegetables can be pickled by using pickled black mustard tuber, root mustard, Chinese cabbage and radish leaf as the preferred raw materials for preparing the black pickled vegetables (the preserved vegetable), the black pickled vegetables are subjected to lactic acid fermentation and then dried in the sun, and then are steamed, braised, aired, steamed, braised and aired into finished products, and the finished products are mainly used for dishes such as preserved pork, preserved vegetable egg soup and the like, the industry of the prefabricated vegetables in China is prosperous, the market scale of the prefabricated vegetables in China is increased by 20 percent year by year, and the pickled black pickled vegetable is the next ten thousand-year catering market. The production and consumption of the braised pork with preserved vegetable in the plum at least exceed one hundred million parts per year in Hunan alone, the output value is at least more than 50 hundred million yuan, and one part of braised pork with preserved vegetable is calculated by 100g, the dosage of only one single item of dried plum per year exceeds 1000 tons, and the area of the vegetable for planting leaves is at least more than 10000 mu, so that the method plays a great supporting role in the growth of the industry in the Xingxing.

However, the existing processing technology of the preserved vegetables is complex, and has the problems of no datamation, insufficient standardization, lack of optimization technology, unstable quality and the like, and the specific operation process has the following problems: (1) the method comprises the following steps of (1) harvesting different seasons of each leaf vegetable, short picking time, unstable fermentation control, large quality difference and incapability of controlling the old and tender degree of vegetable leaves, so that the too tender part of the fermentation process is easy to melt, the old part of the fermentation process has high fiber content, and the commodity characteristics of products are influenced, (2) the quality of each leaf vegetable is different, and the difference of different raw material components, even the difference of lactobacillus fermentum, causes large quality and flavor difference; (3) the content of dietary fiber of the leaf vegetables is high, and the taste of the product is influenced because the leaf vegetables are very rough after being steamed and dried for many times.

Disclosure of Invention

The invention aims to provide a processing technology of black pickled vegetables and a product thereof, and aims to solve the problems in the prior art.

In order to achieve the purpose, the invention provides the following scheme:

the invention provides a Lactobacillus plantarum (Lactobacillus plantarum) which is preserved in the China general microbiological culture Collection center of China Committee for culture Collection of microorganisms, has the preservation number of CGMCC No.22097, the preservation date of 2021 year, 3 month and 30 days, and the preservation address of No. 3 Silu 1 of Beijing, the sunward area.

The invention also provides application of the lactobacillus plantarum in processing of black pickled vegetables.

The invention also provides a processing technology of the black pickled vegetables, which comprises the following steps:

(1) cleaning and cutting: cleaning fresh vegetable leaves, drying the water on the surface of the fresh vegetable leaves by blowing, and then cutting the vegetable into sheets or strips;

(2) and (3) heat preservation fermentation: inoculating Lactobacillus (Lactobacillus casei) and the Lactobacillus plantarum into the cut vegetables for fermentation to obtain fermented vegetables; the Lactobacillus is Lactobacillus (Lactobacillus casei) CGMCC No. 1.8727;

(3) and (3) dehydrating: dehydrating the water in the fermented vegetables and reducing the water content to 30-45 wt%;

(4) and (3) drying: drying the dehydrated vegetables by a steam drying method until the water content is 20-30 wt%;

(5) complex enzyme treatment: adding neutral cellulase, tannase and pectinase into the dried vegetables for enzymolysis to obtain the vegetables subjected to enzymolysis;

(6) high-pressure steaming: steaming the vegetables for 4 times under high pressure after enzymolysis to obtain the vegetables steamed under high pressure;

(7) drying: the vegetables are dried after the high-pressure steaming until the water content is reduced to 15 to 25 weight percent,

(8) spreading and moisture regaining: spreading the dried product until the water content is 25-30 wt% to obtain the black pickled vegetable.

Further, in the step (2), the temperature of the heat preservation fermentation is 30 ℃, and the time is 2-5 days.

Further, in the step (3), the dehydration is performed by centrifugation or extrusion.

Further, in the step (4), the drying temperature is 50-60 ℃.

Further, in the step (5), the addition amount of the neutral cellulase is 0.03-0.05 wt%, the addition amount of the tannase is 0.01-0.03 wt%, and the addition amount of the pectinase is 0.02-0.04 wt%.

Further, in the step (5), the conditions of the enzymolysis are as follows: the temperature is 50-60 ℃, the pH value is 4.5-6.0, and the time is 2-4 h.

Further, in the step (6), the high-pressure steaming is specifically performed by: steaming at 121 deg.C for 1 hr, directly and rapidly releasing pressure, spraying with steamed water, and continuously steaming.

The invention also provides the black pickled vegetable prepared by the processing technology.

The invention discloses the following technical effects:

the invention overcomes the defects brought by the traditional process, and adopts the inoculated lactobacillus for pre-fermentation and the added enzyme preparation for assistance, thereby not only ensuring the stable fermentation quality, but also adopting leaf vegetables with different sources as raw materials and being carried out in different seasons, realizing the homogenization of different raw materials, simultaneously ensuring the content of the soluble dietary fiber to be improved, and achieving the softening effect. In addition, a continuous production process is adopted, namely, a continuous cooking, stewing, maturing and drying mode is adopted, so that the continuity of production is ensured, and the commodity characteristics and market attributes of the product are ensured.

Drawings

FIG. 1 is a gram-stained photograph of LPHN-6 strain;

FIG. 2 shows a phylogenetic tree identified by LPHN-6.

Detailed Description

Reference will now be made in detail to various exemplary embodiments of the invention, the detailed description should not be construed as limiting the invention but as a more detailed description of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Further, for numerical ranges in this disclosure, it is understood that each intervening value, between the upper and lower limit of that range, is also specifically disclosed. Every smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in a stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference herein for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the present disclosure without departing from the scope or spirit of the disclosure. Other embodiments will be apparent to those skilled in the art from consideration of the specification. The description and examples are intended to be illustrative only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are open-ended terms that mean including, but not limited to.

The lactic acid bacteria (Lactobacillus casei) CGMCC No.1.8727 used in the following examples was purchased from China general microbiological culture Collection center;

in the following examples, neutral cellulase (50U/mg, relative molecular weight: 58.7KD, activity defined as 1 enzyme activity unit for 1 hour hydrolysis of substrate (filter paper, CMC, absorbent cotton or salicyl) to produce 1mg of glucose at 50 deg.C and pH4.8, temperature range of 40-60 deg.C, preferably 50 deg.C) was used; pectinase (500U/mg, 1 g enzyme powder or 1mL enzyme solution at 50 deg.C and pH3.5, 1 enzyme activity unit of enzyme catalyzing hydrolysis of pectin to produce 1 μ g galacturonic acid per hour); tannase (200U/g,1U represents the change in absorbance at 310 nm/minute at a pH of 4.7 and a temperature of 30 ℃ with 3mL of tannic acid as a substrate).

EXAMPLE 1 isolation, identification, preservation of the Strain

First, separate

Separating a strain from sour bamboo shoot, and naming the strain as LPHN-6.

II, identification

1. Morphological identification

The gram-stained picture of LPHN-6 is shown in FIG. 1(10 × 100 times), and it is identified that LPHN-6 belongs to gram-positive bacteria, and it is found that the bacteria can ferment with lactose, glucose, fructose, mannose, xylose, rhamnose, raffinose, maltose and sucrose, except that esculin, gelatin and catalase are negative.

2. Molecular biological identification

And (3) identification process:

2.1 DNA extraction

The TSINGKE plant DNA extraction kit (universal type) is used, and the specific steps are as follows:

(1) placing Spin Column in Collection Tube, adding 250 μ L Buffer BL, and centrifuging at 12000rpm/min for 1min to activate silica gel membrane;

(2) samples of dried tissue (no more than 20mg) were taken and ground thoroughly with liquid nitrogen. Grinding, placing in a 1.5mL centrifuge tube, adding 400 μ l Buffer gP1, vortex oscillating for 1min, and water bath at 65 ℃ for 10-30 min, wherein the mixture can be taken out, inverted and mixed uniformly for full cracking;

(3) adding 150 μ L Buffer gP2, vortex and shake for 1min, ice bath for 5 min;

(4) centrifuging at 12000rpm/min for 5min, and transferring the supernatant into a new centrifuge tube;

(5) adding absolute ethyl alcohol with the same volume as the supernatant, immediately and fully oscillating and uniformly mixing, transferring all liquid into Spin Column, centrifuging at 12000rpm/min for 30s, and discarding waste liquid;

(6) adding 500 mu L Buffer Pw (absolute ethyl alcohol is added before use) into Spin Column, centrifuging at 12000rpm/min for 30s, and discarding waste liquid;

(7) adding 500 mu L of Wash Buffer (absolute ethyl alcohol is added before use) into Spin Column, centrifuging at 12000rpm/min for 30s, and discarding the waste liquid;

(8) repeating the operation step 7;

(9) putting Spin Column back into Collection Tube, centrifuging at 12,000rpm/min for 2min, uncovering and air drying for 1 min;

(10) taking out Spin Column, putting into a clean centrifuge tube, adding 50-100 μ L TE Buffer (preheating TE Buffer at 65 ℃) at the center of the adsorption film, standing for 2min at 20-25 ℃, and centrifuging for 2min at 12,000 rpm/min.

2.2 PCR amplification

(1) Universal primer for identifying bacterial strains

The extracted DNA sample is diluted in proper amount and used as PCR template, and amplification is carried out by Scenario 1 XTSE 101 gold medal mix, and the components of the amplification system are as follows:

1 × TSE101 gold medal mix	45μL
		27F(10P)	2μL
1492R(10P)	2μL
		DNA template	1μL

The above amplification system was amplified according to the following amplification procedure:

2.3 electrophoretic detection

The amplified PCR product was subjected to agarose gel electrophoresis (2. mu.L sample + 6. mu.L bromophenol blue) at 300V for 12 minutes to obtain an identification gel image. The prepared PCR product was sent to the sequencing department of the Sichuan organism for one-generation sequencing (27F/1492R as sequencing primer). The construction of a phylogenetic tree is shown in FIG. 2.

Through identification, LPHN-6 is a strain of Lactobacillus plantarum (Lactobacillus plantarum).

3. Preservation of

The strain LPHN-6 is preserved in the common microorganism center of China Committee for culture Collection of microorganisms, the preservation number is CGMCC No.22097, the preservation date is 2021 years, 3 months and 30 days, and the preservation address is No. 3 of Xilu No.1 of Beijing, Chaoyang, Beicheng.

Example 2

The processing technology of the embodiment is as follows:

(1) after the harvesting of the fresh leaf mustard is finished, an automatic spraying cleaning device is used for cleaning and removing impurities, and the moisture on the surface is dried by adopting a wind force forced combination vibration mode.

(2) The vegetable is cut into pieces or strips by an automatic vegetable cutter without sticking.

(3) And (3) heat preservation fermentation: inoculating starter of lactobacillus CGMCC No.1.8727 and lactobacillus plantarum CGMCC No.22097 capable of producing bacteriocin, fermenting at the inoculation amount of 0.05% (W/W) at 30 deg.C for 2 days. This step can reduce the unpleasant smell of the pathogens in the natural fermentation process.

Preparing a leavening agent: the two strains are respectively cultured by adopting MRS culture media, and the culture conditions are as follows: standing at 30 deg.C for 72 hr, and centrifuging to obtain bacterial sludge as leaven.

(4) And (3) dehydrating: the water content in the fermented vegetable is reduced to 30 wt% by adopting a centrifugal dehydration or extrusion dehydration mode.

(5) Drying: a steam drying method is adopted, the temperature is controlled to be 50 ℃, and the drying is carried out until the moisture content is 30 wt%.

(6) Complex enzyme treatment: adding neutral cellulase 0.03%, tannase 0.01% and pectase 0.02% relative to the weight of the dried vegetable in step (5) at 50 deg.C, and performing enzymolysis at pH4.5 for 4 hr.

(7) High-pressure steaming: steaming at 121 ℃, directly and quickly releasing pressure after steaming for 1 hour, then completely and slowly pouring and thoroughly pouring by using the steamed water, continuously steaming after pouring and pouring, repeating for 4 times, ensuring uniform and stable color and luster, and the quick pressure release process is also a process for releasing evil and foreign flavor, loosening materials and being beneficial to the pouring effect.

(8) Drying: the temperature is controlled at 45 ℃, and the moisture content is reduced to 25 wt% to meet the requirement.

(9) Spreading and moisture regaining: the dried product is properly backwashed until the water content is 30 wt%, thus obtaining the finished product.

TABLE 1 volatile components of black pickles in example 2 after the first autoclaving in the step (7)

TABLE 2 volatile components of black pickled vegetables in example 2 after the fourth high-pressure cooking in the step (7)

TABLE 3 volatile ingredients of black pickled vegetables after atmospheric cooking

CAS	Name of Chinese	Name of English	Molecular formula	Molecular mass	Similarity SI	Retention time	Area of	Relative amounts of
									294-93-9	12-crown-4-Ether	12-Crown-4	C8H16O4	176	89	3.146	342942	12.52
469-61-4	alpha-cedrene	(-)-alpha-cedrene	C15H24	204	93	10.701	339729	12.41
									546-28-1	B-cedrene	(+)-β-CEDRENE	C15H24	204	89	11.113	71818	2.62
77-53-2	Cedarwood jelly	cedrol	C15H26O	222	97	17.97	1394025	50.91
									502-69-2	Phytolone	Perhydrofarnesyl Acetone	C18H36O	268	97	18.436	589680	21.54

By comparing the volatile components after the first (table 1) and the fourth (table 2) high-pressure cooking treatments, it is found that the continuous four times of cooking, the intermediate pressure relief and the pouring are beneficial to the optimization of the volatile components, the volatile components after the four times of cooking are more harmonious, most of the volatile components in the normal-pressure cooking process (table 3) are taken away by steam in the cooking process, although cedarwood brain and the like are similarly concentrated and have obviously improved contents, the flavor is not good in high-pressure cooking effect, and the Hexahydrofarnesenyl acetate (6, 10, 14-Trimethyl-2-pentadecanone) is the sesquiterpene separated from Launea mcronata and is the main component of the volatile oil. Hexahydrofarnesyl acetone has antibacterial, analgesic and anti-inflammatory activities. The cedar brain (fragrance) has the sleep improving effect which is comparable to that of hypnotic.

Short high-pressure steaming time, good effect, long normal-pressure steaming time, large loss of volatile components and large energy consumption. The steaming process does optimize the volatile components of the black pickles, wherein cedrol is a biologically active sesquiterpene with anti-sepsis, anti-inflammatory, anti-spasmodic, tonic, astringent, diuretic, sedative, insecticidal and antifungal activities. The phytone has the effects of improving fragrance and reducing miscellaneous gas, so that the proper consumption of the black pickled vegetable is beneficial to body health.

Example 3

The processing technology of the embodiment is as follows:

(3) And (3) heat preservation fermentation: inoculating starter of lactobacillus CGMCC No.1.8727 and lactobacillus plantarum CGMCC No.22097 capable of producing bacteriocin, fermenting at the inoculation amount of 0.05% (W/W) at 30 deg.C for 2-5 days. This step can reduce the unpleasant smell of the pathogens in the natural fermentation process.

Preparation of a leavening agent: the two strains are respectively cultured by adopting MRS culture media, and the culture conditions are as follows: standing at 30 deg.C for 72 hr, and centrifuging to obtain bacterial sludge as leaven.

(4) And (3) dehydrating: the water content in the fermented vegetable is reduced to 40 wt% by adopting a centrifugal dehydration or extrusion dehydration mode.

(5) And (3) drying: the steam drying method is adopted, the temperature is controlled to be 55 ℃, and the drying is carried out until the moisture content is 25 wt%.

(6) Complex enzyme treatment: and (3) adding neutral cellulase, tannase and pectinase which are 0.04 percent, 0.02 percent and 0.03 percent relative to the weight of the dried vegetables in the step (5) at the temperature of 55 ℃, and performing enzymolysis for 3 hours under the condition of pH 5.5.

(7) High-pressure steaming: steaming at 121 ℃, directly and quickly releasing pressure after steaming for 1 hour, then completely and slowly pouring and thoroughly pouring by using the steamed water, continuously steaming after pouring and pouring, repeating for 4 times, ensuring uniform and stable color and luster, wherein the pressure release process is also a process for releasing evil and foreign flavor, loosening materials and being beneficial to the pouring and pouring effect.

(8) Drying: the temperature is controlled at 50 ℃, and the water content is reduced to 20 wt% to meet the requirement.

(9) Spreading and moisture regaining: the dried product is properly backwashed until the water content is 25 wt%, thus obtaining the finished product.

Example 4

The processing technology of the embodiment is as follows:

(1) after the fresh leaf mustard is harvested, an automatic spraying cleaning device is used for cleaning and removing impurities, and the surface moisture is dried by adopting a wind force forced combination vibration mode.

(4) And (3) dehydrating: the water content in the fermented vegetable is reduced to 45 wt% by adopting a centrifugal dehydration or extrusion dehydration mode.

(5) Drying: the steam drying method is adopted, the temperature is controlled to be 60 ℃, and the drying is carried out until the moisture content is 20 wt%.

(6) Complex enzyme treatment: adding neutral cellulase 0.05%, tannase 0.03% and pectinase 0.04% relative to the weight of the dried vegetables in step (5) at 60 deg.C, and performing enzymolysis at pH6.0 for 2 hr.

(7) High-pressure steaming: steaming at 121 deg.C for 1 hr, directly releasing pressure, slowly pouring with steamed water, pouring thoroughly, continuously steaming after pouring, repeating for 4 times, ensuring uniform and stable color, and releasing odor, loosening material, and benefiting pouring.

(8) Drying: the temperature is controlled at 55 ℃, and the water content is reduced to 15 wt% generally, so that the requirement can be met.

Comparative example 1

The original processing technology comprises the following steps:

(1) after the collection of the fresh leaf mustard is finished, cleaning and impurity removal are carried out, and the moisture on the surface is forced to blow dry by wind power;

(2) cutting different vegetable leaves into sheets or strips by using a manual or vegetable cutter without adhesion;

(3) extruding and fermenting: traditionally, the natural fermentation is carried out for 3 to 5 days by adopting artificial picking and compacting, the temperature is generally 1 to 2 days when exceeding 30 ℃, and the total acid content is about 1 percent.

(4) Drying: drying by natural light or steam for standby

(5) Steaming for the first time: steaming for 4-6 hr in wooden steamer while circulating normal pressure steaming.

(6) Primary stewing: steaming for 10 hr

(7) Drying for the first time: drying by utilizing natural light and sun for later use;

(8) steaming for the second time: steaming for 4-6 hr in wooden steamer while circulating normal pressure steaming.

(9) And (3) second stewing: steaming for 10 hr

(10) And (3) drying for the second time: drying by utilizing natural light and sun for later use;

(11) steaming for the third time: steaming for 4-6 hr in wooden steamer while circulating normal pressure steaming.

(12) And (3) stewing for the third time: steaming for 10 hr

(13) And (3) drying for the third time: the finished product is obtained by drying in the sun or baking by natural light.

The black pickled vegetable produced by the process of the comparative example 1 is black and bright in color and luster and rich in smell, and has fragrant smell after being used as an ingredient for steaming the meat of the preserved vegetable, but the process flow is complex, the operation experience is strong, continuous production cannot be realized, and the cellulose content of the product is high but the soluble dietary fiber content is low. Generally, the vegetable dietary fiber is 0.6g/100g (wet basis, water content is 95%), the insoluble dietary fiber of the black pickled vegetable prepared by the traditional method accounts for 0.527g/100g, and the soluble dietary fiber only accounts for 0.073g/100g (calculated according to the wet basis).

Compared with the traditional process of the comparative example 1, the process of the embodiments 2 to 4 simplifies the production process, shortens the production period, inoculates and ferments lactic acid bacteria, reduces the influence caused by different vegetable leaf raw materials to the maximum extent, reduces the influence of mixed bacteria on the fermentation quality, reduces the foreign flavor, stabilizes the quality and the flavor of lactic acid fermentation, achieves the softening effect of the cellulose after the complex enzyme is added for treatment, obviously improves the soluble dietary fiber, adopts the normal-pressure back pouring process to ensure the uniform and stable color of the product, ensures that the prepared black pickled vegetable has sharp aroma and bright color, is softer than the product prepared by the traditional process in steaming, has stronger oil absorption capacity, and is beneficial to forming the sensory characteristic of the braised pork with the preserved vegetables. The content of soluble dietary fiber is improved by more than 10% compared with the content of soluble dietary fiber in the traditional process. In example 2, the insoluble dietary fiber of the black pickled vegetable prepared by the modern enzyme treatment and high pressure treatment combined method accounts for 0.478g/100g, and the soluble dietary fiber accounts for only 0.122g/100g (calculated according to a wet basis).

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.

Claims

1. A lactobacillus plantarum strain is characterized in that the lactobacillus plantarum strain is preserved in China general microbiological culture Collection center (CGMCC) with the preservation number of CGMCC No.22097, the preservation date of 2021 year, 3 months and 30 days, and the preservation address of No. 3 Hospital No.1 of Beijing, northwest of the sunward district.

2. Use of lactobacillus plantarum according to claim 1 in black-pickled vegetable processing.

3. The processing technology of the black pickled vegetables is characterized by comprising the following steps:

(1) cleaning and cutting: cleaning fresh vegetable leaves, drying the surface water in a blowing mode, and then cutting the vegetables into sheets or strips;

(2) and (3) heat preservation fermentation: inoculating Lactobacillus (Lactobacillus casei) and the Lactobacillus plantarum of claim 1 into the cut vegetables for fermentation to obtain fermented vegetables; the Lactobacillus is Lactobacillus (Lactobacillus casei) CGMCC No. 1.8727;

(4) drying: drying the dehydrated vegetables by a steam drying method until the water content is 20-30 wt%;

4. The process for preparing black pickled vegetables according to claim 3, wherein the temperature of the incubation fermentation in step (2) is 30 ℃ for 2-5 days.

5. The process for producing black pickled vegetables according to claim 3, wherein the dehydration is carried out by centrifugation or pressing in the step (3).

6. The process for producing black pickled vegetables according to claim 3, wherein the temperature of the drying step (4) is 50-60 ℃.

7. The process for preparing black pickled vegetables according to claim 3, wherein in the step (5), the neutral cellulase is added in an amount of 0.03 to 0.05 wt%, the tannase is added in an amount of 0.01 to 0.03 wt%, and the pectinase is added in an amount of 0.02 to 0.04 wt%.

8. The process for producing black pickled vegetables according to claim 3, wherein the conditions of the enzymatic hydrolysis in step (5) are as follows: the temperature is 50-60 ℃, the pH value is 4.5-6.0, and the time is 2-4 h.

9. The process for producing black pickled vegetables according to claim 3, wherein in step (6), the high pressure steaming is carried out by: steaming at 121 deg.C for 1 hr, directly releasing pressure, spraying with steamed water, and steaming.

10. A black pickled vegetable prepared by the process according to any one of claims 3 to 9.