Old-jar pickled Chinese cabbage and preparation method thereof

Abstract

The invention discloses an old jar pickled Chinese cabbage and a preparation method thereof, the old jar pickled Chinese cabbage is obtained by fermenting lactobacillus plantarum KSF001, the lactobacillus plantarum KSF001 is preserved in the China General Microbiological Culture Collection Center on June 14, 2024, and the preservation number of the lactobacillus plantarum KSF001 is CGMCC (China General Microbiological Culture Collection Center) No: 30957. According to the pickled Chinese cabbages provided by the embodiment of the invention, the dominant strain lactobacillus plantarum KSF001 screened from existing pickled Chinese cabbage samples of enterprises is adopted to prepare the pickled Chinese cabbages, so that the prepared pickled Chinese cabbages are good in flavor and rich in nutrient substances such as amino acids and lactic acid bacteria, food safety can be ensured, and the pickled Chinese cabbages are suitable for large-scale production. The method solves the problems of long fermentation period, serious loss of flavor nutrient substances, low safety controllability and the like in the traditional jar-returning secondary fermentation process of the pickled Chinese cabbages.

Description

Technical Field

[0001] The invention relates to the field of fermented foods, and in particular to old-style pickled mustard greens and a preparation method thereof. Background Art

[0002] Salted vegetables are traditional fermented foods in my country with a long history and profound culture. They are widely used as side dishes, appetizers and condiments. The crispness, tenderness and sourness of salted vegetables are deeply loved by consumers, and the demand is increasing year by year, which has also prompted the production method of salted vegetables to change from manual workshops to industrial-scale processing.

[0003] At present, the general process of industrial-scale salted vegetables is to use fresh vegetables as raw materials, pickle them with high-concentration salt (more than 12wt%), and then process them through processes such as cleaning, desalting, dehydration, seasoning, filling, and sterilization. Microorganisms grow and metabolize slowly under the high-salt conditions of industrial-scale salted vegetables, and the complicated processes will cause the loss of their fermented flavor. Enterprises can only make up for the flavor of the final product by adding acids, spices, etc. Therefore, most companies have begun to use the method of returning to the altar for secondary fermentation to give salted vegetables the flavor of "old altar pickles" to improve their quality and market competitiveness. The secondary fermentation of industrial-scale salted vegetables refers to the salted vegetables (salted embryos) that have been fermented in the salting tank for a period of time (1-6 months), and after simple processes such as cleaning and desalting, they are put into the pottery altar for fermentation again.

[0004] However, the current industrial-scale secondary fermentation of pickled vegetables in pots is mainly based on natural fermentation, with a long fermentation cycle, often requiring more than one month. This makes it difficult to turn over the pottery pots, which is inefficient to use, and hinders the production of pickled vegetables and corporate benefits. In addition, the cleaning and desalting processes before fermentation in the pots will reduce the number of microorganisms, resulting in weak secondary fermentation and low acid production, making it difficult to achieve the flavor of "old pot pickles". Moreover, when pickled vegetables are processed through multiple processes, they may contaminate environmental microorganisms, causing the pickled vegetables to grow film, soften, and other corruption, and the content of nitrite and biogenic amines is high, which seriously affects the edible safety of pickled vegetables. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a traditional pickled cabbage and a preparation method thereof, which solves the problems of long fermentation cycle, serious loss of flavor nutrients, low safety controllability, etc. in the traditional pickled cabbage secondary fermentation process.

[0006] The invention provides a traditional Chinese pickled cabbage. The traditional Chinese pickled cabbage is obtained by fermenting Lactobacillus plantarum KSF001. The Lactobacillus plantarum KSF001 is deposited in China General Microbiological Culture Collection Center on June 14, 2024, with a deposit address in Beijing, China, and a deposit number of CGMCC No: 30957.

[0007] The present invention also provides a method for preparing old-style pickled cabbage, which is used to prepare the old-style pickled cabbage as described above, and the preparation method comprises:

[0008] First fermentation step: fresh green vegetables are added with salt for sealed fermentation to obtain salt-cured mature green vegetables;

[0009] Washing step: washing the salted mature green vegetables, draining to obtain washed green vegetables, and measuring the salinity of the washed green vegetables;

[0010] The second fermentation step: placing the washed green vegetables in a pickle jar, adding mother water containing the Lactobacillus plantarum KSF001, and fermenting to obtain the old pickled vegetables.

[0011] Optionally, the first fermentation step comprises:

[0012] Fresh green vegetables that meet food safety requirements are added with iodine-free salt, wherein the weight ratio of the fresh green vegetables to the iodine-free salt is 100:8-16. The vegetables are placed in a pickling tank in a layer of fresh green vegetables and a layer of iodine-free salt, and sealed and fermented for more than 3 months.

[0013] Optionally, the cleaning step includes:

[0014] The salted mature green vegetables are washed by a bubbling washing machine and drained to obtain washed green vegetables. The salinity of the washed green vegetables is measured. The salinity of the washed green vegetables is controlled to be 5wt% to 8wt%.

[0015] Optionally, the mother water containing the Lactobacillus plantarum KSF001 is prepared by the following method:

[0016] Weigh 140kg to 165kg of pure water or tap water, calculate the amount of salt to be added according to the salinity of the washed green vegetables and the equilibrium salinity of the final vegetable water, then mix and dissolve the salt, 4kg to 7kg of white sugar and 140kg to 165kg of water to obtain salt water, wherein the equilibrium salinity is controlled at 5wt% to 6.5wt%;

[0017] The activated Lactobacillus plantarum KSF001 is added to the salt water to obtain mother water containing the Lactobacillus plantarum KSF001.

[0018] Optionally, the activated Lactobacillus plantarum KSF001 is obtained by the following method:

[0019] 100 mL of pure water, 1 g of salt and 1 g of white sugar were placed in a conical flask, and 5 g of the Lactobacillus plantarum KSF001 was added after shaking and dissolving, and covered with a latex stopper after shaking, and placed in a 37° C. incubator for 1 hour to obtain the activated Lactobacillus plantarum KSF001.

[0020] Optionally, the second fermentation step comprises:

[0021] The cleaned green vegetables are placed in a kimchi jar, and the green vegetables are fixed at the mouth of the kimchi jar with bamboo strips. After fixation, mother water containing Lactobacillus plantarum KSF001 is added to submerge the green vegetables and reach the bottom edge of the kimchi jar. Then, water is added to seal the jar for fermentation to obtain the old-style pickled vegetables.

[0022] Optionally, in the second fermentation step, the weight ratio of the green vegetables to the mother water is 2.5-3.5:1.

[0023] Optionally, the green vegetable is broadleaf mustard.

[0024] Optionally, in the second fermentation step, the fermentation temperature is 20°C to 30°C.

[0025] The traditional pickled mustard greens and the preparation method thereof provided by the embodiments of the present invention have the following advantages compared with the prior art:

[0026] The traditional pickled cabbage provided in the embodiment of the present invention is prepared by using the dominant strain Lactobacillus plantarum KSF001 screened out from existing traditional pickled cabbage samples of the enterprise, so that the prepared traditional pickled cabbage has good flavor, is rich in nutrients such as amino acids and lactic acid bacteria, and can ensure food safety.

[0027] In addition, the method for preparing old-style pickled cabbage provided by the embodiment of the present invention applies the dominant strain Lactobacillus plantarum KSF001 to the method for preparing old-style pickled cabbage of the present invention, and through the first fermentation step, the cleaning step, and the second fermentation step, can realize rapid start-up fermentation in the industrial production application of pickled cabbage, with large acid production, shortening the time of the secondary fermentation of pickled cabbage, and making the prepared old-style pickled cabbage have good flavor, rich nutrients such as amino acids and lactic acid bacteria, and can ensure food safety.

[0028] Furthermore, by applying superior strains for fermentation and optimizing key fermentation processes and parameters (the weight ratio of green vegetables to mother water, salinity control in the cleaning step and the second fermentation step, and fermentation temperature control in the second fermentation step), the flavor of old-style pickled cabbage was improved, and a old-style pickled cabbage product with stable quality (stable total acid, pH, salinity and nutritional indicators, and small fermentation differences in different regions), good flavor, and rich nutrition (amino acids and lactic acid bacteria) was obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The present invention is a process flow chart of traditional pickled cabbage in an embodiment of the present invention.

[0030] Figure 2 The total acid determination results of the sauerkraut samples in Example 1 and Comparative Example 1 are shown.

[0031] Figure 3 The pH measurement results of the sauerkraut samples in Example 1 and Comparative Example 1 are shown.

[0032] Figure 4 The microbial count results of the sauerkraut samples in Example 1 and Comparative Example 1 are shown.

[0033] Figure 5 The following are the results of flavor substance determination of sauerkraut samples in Example 1 and Comparative Example 1.

[0034] Figure 6 These are the results of determining the biogenic amine content of the sauerkraut samples in Example 1 and Comparative Example 1.

[0035] Figure 7 These are the total acid determination results of multiple rounds of sauerkraut samples in Example 2 and Comparative Example 2.

[0036] Figure 8 These are the microbial count results of the sauerkraut samples in Example 2 and Comparative Example 2.

[0037] Fig. 9 The total acid determination results of the sauerkraut samples in Example 3 and Comparative Example 3 are shown.

[0038] Fig.10 These are the microbial count results of the sauerkraut samples in Example 3 and Comparative Example 3.

[0039] Fig.11 The total acid determination results of multiple rounds of sauerkraut samples were obtained by applying Example 1 and Comparative Example 1 to three different companies.

[0040] Fig.12 The amino acid determination results of multiple rounds of sauerkraut samples were obtained by applying Example 1 and Comparative Example 1 to three different companies. DETAILED DESCRIPTION

[0041] As described in the background technology, the current industrial-scale secondary fermentation of salted vegetables is mainly based on natural fermentation, and the fermentation cycle is long, often requiring more than one month, which will make it difficult to turn over the pottery pots, and the use efficiency is low, which hinders the production of salted vegetables and the benefits of enterprises. In addition, the cleaning and desalting processes before the fermentation in the pot will reduce the number of microorganisms, resulting in weak secondary fermentation and low acid production, making it difficult to achieve the flavor of "old pot pickles". Moreover, salted vegetables may contaminate environmental microorganisms when processed through multiple processes, resulting in the growth of film and softening of salted vegetables, and the high content of nitrite and biogenic amines, which seriously affects the edible safety of salted vegetables.

[0042] After research and development, the inventors found that the main problems with the secondary fermentation process of sauerkraut are: first, the fermentation is mainly carried out in pottery jars, and the number and site of pottery jars are limited, so it is necessary to shorten the fermentation cycle and improve the turnover rate of earthen jars; second, the vegetables have undergone a long period of fermentation during the first salting period, and their basic nutritional substrates such as carbon source and nitrogen source have been almost exhausted. In addition, the salt embryo will be washed, desalted, cut and other processes before returning to the jar, which will cause the flavor nutrients of the salted vegetables to be further lost, making secondary fermentation difficult. At present, enterprises mainly use old mother water for immersion in the jar for fermentation, but the old mother water has low output in industrial production, is in short supply, and is difficult to produce sustainably, and the flavor of the product seasoned by acid adjustment is not as good as the traditional fermentation flavor. Third, the existing inoculation fermentation is immature, and the fermentation cycle is long, and the economic cost is high.

[0043] After further research, the inventors found that by optimizing the inoculation fermentation and optimizing the key process of secondary fermentation in the jar, it is expected to break through the above-mentioned industry bottleneck problems and enhance the flavor and nutritional value of old-style pickled cabbage.

[0044] In order to solve the above technical problems, the old-style pickled cabbage provided in the embodiment of the present invention is prepared by using the dominant strain Lactobacillus plantarum KSF001 screened out from the existing old-style pickled cabbage samples of the enterprise, so that the prepared old-style pickled cabbage has good flavor, is rich in nutrients such as amino acids and lactic acid bacteria, and can ensure food safety.

[0045] In addition, the method for preparing old-style pickled cabbage provided by the embodiment of the present invention applies the dominant strain Lactobacillus plantarum KSF001 to the method for preparing old-style pickled cabbage of the present invention, and through the first fermentation step, the cleaning step, and the second fermentation step, can realize rapid start-up fermentation in the industrial production application of pickled cabbage, with large acid production, shortening the time of the secondary fermentation of pickled cabbage, and making the prepared old-style pickled cabbage have good flavor, rich nutrients such as amino acids and lactic acid bacteria, and can ensure food safety.

[0046] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0047] Unless otherwise specified, the raw materials, samples, reagents, and equipment used in the embodiments of the present invention are all commercially available and can be purchased on the market.

[0048] The strains used in the following examples of the present invention are derived from the following:

[0049] Lactobacillus plantarum KSF001 is separated from an existing old-style pickled cabbage sample of an enterprise in Meishan City, Sichuan Province. After determining the acid production capacity and safety test, Lactobacillus plantarum KSF001 is used for old-style pickled cabbage fermentation. The Lactobacillus plantarum KSF001 is deposited in the China General Microbiological Culture Collection Center on June 14, 2024, and the deposit number is: CGMCC 30957.

[0050] The embodiment of the present invention provides a traditional pickled cabbage, which is obtained by fermenting Lactobacillus plantarum KSF001. The Lactobacillus plantarum KSF001 was deposited in the China General Microbiological Culture Collection Center on June 14, 2024, with a deposit number of CGMCC No: 30957.

[0051] Please refer to Figure 1 , Figure 1 The present invention is a process flow chart of traditional pickled cabbage in an embodiment of the present invention.

[0052] As described below, an embodiment of the present invention provides a method for preparing old-style pickled cabbage, which is used to prepare the old-style pickled cabbage described in the embodiment of the present invention. The preparation method includes the following steps.

[0053] S100, the first fermentation step: adding salt to fresh green vegetables for sealed fermentation to obtain salt-pickled mature green vegetables.

[0054] In some embodiments, the first fermentation step comprises:

[0055] Fresh green vegetables that meet food safety requirements are added with iodine-free salt, wherein the weight ratio of the fresh green vegetables to the iodine-free salt is 100:8-16. The vegetables are placed in a pickling tank in a layer of fresh green vegetables and a layer of iodine-free salt, and sealed and fermented for more than 3 months.

[0056] Optionally, the greens are large-leaf mustard greens, which have high yield and production capacity, and less leaf fiber, and are suitable for long-term pickling into traditional pickled mustard greens.

[0057] S200, washing step: washing the salted mature green vegetables, draining to obtain washed green vegetables, and measuring the salinity of the washed green vegetables.

[0058] In some embodiments, the washing step includes: washing the salted mature greens with a bubbling washing machine, draining to obtain washed greens, and measuring the salinity of the washed greens, wherein the salinity of the washed greens is controlled to be between 5wt% and 8wt%. It should be noted that the salinity of the washed greens is the mass of salt / the mass of the washed greens.

[0059] S300, a second fermentation step: placing the washed green vegetables in a pickle jar, adding mother water containing the Lactobacillus plantarum KSF001, and fermenting to obtain the old pickled vegetables.

[0060] In some embodiments, the mother water containing the Lactobacillus plantarum KSF001 is prepared by the following method: weighing 140Kg to 165Kg of pure water or tap water, calculating the amount of salt to be added according to the salinity of the washed green vegetables and the equilibrium salinity of the final vegetable water, and then mixing and dissolving the salt, 4Kg to 7Kg ​​of white sugar and 140Kg to 165Kg of water to obtain brine, wherein the equilibrium salinity is controlled at 5wt% to 6.5wt%; adding the activated Lactobacillus plantarum KSF001 to the brine to obtain the mother water containing the Lactobacillus plantarum KSF001.

[0061] It should be noted that the equilibrium salinity is the final ratio of the green vegetables and the salt water in the jar, and the equilibrium salinity in the embodiment of the present invention is 5wt% to 6.5wt%. In specific implementation, the amount of salt to be added when preparing the mother water can be calculated based on the salt content of the green vegetables and the equilibrium salinity value.

[0062] In some embodiments, the activated Lactobacillus plantarum KSF001 is obtained by the following method: 100 mL of pure water, 1 g of table salt and 1 g of white sugar are placed in a conical flask, and 5 g of the Lactobacillus plantarum KSF001 is added after shaking to dissolve, and then covered with a latex stopper after shaking, and placed in a 37° C. incubator for 1 hour to obtain the activated Lactobacillus plantarum KSF001.

[0063] Optionally, in some embodiments, the second fermentation step includes: placing the washed green vegetables in a kimchi jar, fixing the green vegetables at the mouth of the kimchi jar with bamboo strips, and then adding mother water containing the Lactobacillus plantarum KSF001 after fixation, so that the mother water submerges the green vegetables and reaches the bottom edge of the kimchi jar, and then adding water at the edge of the jar to seal the jar for fermentation to obtain the old-style jar pickled cabbage.

[0064] Optionally, in some embodiments, in the second fermentation step, the weight ratio of the green vegetables to the mother water is 2.5-3.5:1.

[0065] Optionally, in some embodiments, in the second fermentation step, the fermentation temperature is 20°C to 30°C.

[0066] The invention improves the flavor of old-style pickled cabbage by applying superior strains for fermentation and optimizing key fermentation processes and parameters (the weight ratio of green vegetables to mother water, salinity control in a washing step and a second fermentation step, and fermentation temperature control in the second fermentation step), and obtains an old-style pickled cabbage product with stable quality (stable total acid, pH, salinity and nutritional indicators, and small fermentation difference in different regions), good flavor, and rich nutrition (amino acids and lactic acid bacteria).

[0067] Example 1 Preparation of Old Pickled Cabbage

[0068] 1. Materials

[0069] Activated Lactobacillus plantarum KSF001 is obtained by the following method:

[0070] Put 100 mL of pure water, 1 g of salt and 1 g of white sugar in a conical flask, shake well to dissolve, add 5 g of Lactobacillus plantarum KSF001, shake well, cover with a latex stopper, and place in a 37° C. incubator for 1 hour to obtain activated Lactobacillus plantarum KSF001.

[0071] Greens: Large-leaf mustard greens.

[0072] 2. Preparation method

[0073] (1) First fermentation: Add iodine-free salt to food-safe vegetables, with the weight ratio of fresh vegetables to iodine-free salt being 100:12. Place the vegetables in a pickling tank in a layer of fresh vegetables and a layer of iodine-free salt, and ferment for more than 3 months.

[0074] (2) Cleaning: 1100 kg of salted mature green vegetables were cleaned using a bubbling cleaning machine and drained to obtain cleaned green vegetables. The salinity of the cleaned green vegetables was measured and the salinity of the cleaned green vegetables was controlled to be 7.5 wt %.

[0075] (3) Preparation of mother water containing Lactobacillus plantarum KSF001: Weigh 150 kg of tap water, calculate the amount of salt to be added according to the salinity of the washed green vegetables and the equilibrium salinity of the final vegetable water, and do not add salt to the water because the salinity of the washed green vegetables is 7.5 wt %. Then, 4 kg of white sugar is mixed with 150 kg of water and dissolved to obtain salt water, and the equilibrium salinity is controlled at 5 wt %. Activated Lactobacillus plantarum KSF001 is added to the salt water to obtain mother water containing Lactobacillus plantarum KSF001.

[0076] (4) Second fermentation: 350 kg of washed green vegetables are placed in a kimchi jar, and the green vegetables are fixed at the mouth of the kimchi jar with bamboo strips. After fixation, mother water containing Lactobacillus plantarum KSF001 is added, and the weight ratio of green vegetables to mother water is 3:1. The mother water is made to submerge the green vegetables and reach the bottom edge of the kimchi jar. Then, water is added to the jar edge to seal the jar and ferment it at 25°C for 8 days to obtain old jar pickled vegetables.

[0077] Example 2 Preparation of Old Pickled Cabbage

[0078] 1. Materials

[0079] The activated Lactobacillus plantarum KSF001 is obtained by the following method:

[0080] 100 mL of pure water, 1 g of salt and 1 g of sugar were placed in a conical flask, and 5 g of Lactobacillus plantarum KSF001 was added after shaking to dissolve, and the mixture was covered with a latex stopper after shaking, and the mixture was placed in a 37° C. incubator for 1 hour to obtain activated Lactobacillus plantarum KSF001.

[0081] Greens: Large-leaf mustard greens.

[0082] 2. Preparation method

[0083] (1) First fermentation: Add iodine-free salt to food-safe vegetables, with the weight ratio of fresh vegetables to iodine-free salt being 100:12. Place the vegetables in a pickling tank in a layer of fresh vegetables and a layer of iodine-free salt, and ferment for more than 3 months.

[0084] (2) Cleaning: 3300 kg of salt-ripened green vegetables were cleaned using a bubbling cleaning machine and drained to obtain cleaned green vegetables. The salinity of the cleaned green vegetables was measured and the salinity of the cleaned green vegetables was controlled at 7.5 wt %.

[0085] (3) Preparation of mother water containing Lactobacillus plantarum KSF001: Weigh 150 kg of tap water, calculate the amount of salt to be added according to the salinity of the washed green vegetables and the equilibrium salinity of the final vegetable water, and do not add salt to the water because the salinity of the washed green vegetables is 7.5 wt %. Then, mix 4.8 kg of white sugar with 150 kg of water and dissolve them to obtain salt water, and control the equilibrium salinity to 6 wt %. Add activated Lactobacillus plantarum KSF001 to the salt water to obtain mother water containing Lactobacillus plantarum KSF001.

[0086] (4) Second fermentation: 400 kg of washed green vegetables are placed in a kimchi jar and fixed at the mouth of the kimchi jar with bamboo strips. After fixation, mother water containing Lactobacillus plantarum KSF001 is added, and the weight ratio of green vegetables to mother water is 3:1. The mother water is made to submerge the green vegetables and reach the bottom edge of the kimchi jar. Then, water is added to seal the jar and fermented at 25°C for 7 days to obtain old-style pickled cabbage.

[0087] Example 3 Preparation of Old Pickled Cabbage

[0088] 1. Materials

[0089] Activated Lactobacillus plantarum KSF001 is obtained by the following method:

[0090] 100 mL of pure water, 1 g of salt and 1 g of sugar were placed in a conical flask, and 5 g of Lactobacillus plantarum KSF001 was added after shaking to dissolve, and the mixture was covered with a latex stopper after shaking, and the mixture was placed in a 37° C. incubator for 1 hour to obtain activated Lactobacillus plantarum KSF001.

[0091] Greens: Large-leaf mustard greens.

[0092] 2. Preparation method

[0093] (1) First fermentation: Add iodine-free salt to food-safe vegetables, with the weight ratio of fresh vegetables to iodine-free salt being 100:12. Place the vegetables in a pickling tank in a layer of fresh vegetables and a layer of iodine-free salt, and ferment for more than 3 months.

[0094] (2) Cleaning: 3300 kg of salt-ripened green vegetables were cleaned with a bubbling cleaning machine and drained to obtain cleaned green vegetables. The salinity of the cleaned green vegetables was measured and the salinity of the cleaned green vegetables was controlled at 7.5 wt %.

[0095] (3) Preparation of mother water containing Lactobacillus plantarum KSF001: Weigh 180 kg of tap water, calculate the amount of salt to be added according to the salinity of the washed green vegetables and the equilibrium salinity of the final vegetable water, and do not add salt to the water because the salinity of the washed green vegetables is 7.5 wt %. Then, 4.8 kg of white sugar is mixed with 180 kg of water and dissolved to obtain salt water, and the equilibrium salinity is controlled at 6.5 wt %. Activated Lactobacillus plantarum KSF001 is added to the salt water to obtain mother water containing Lactobacillus plantarum KSF001.

[0096] (4) Second fermentation: 400 kg of washed green vegetables are placed in a kimchi jar, and the green vegetables are fixed at the mouth of the kimchi jar with bamboo strips. After fixation, mother water containing Lactobacillus plantarum KSF001 is added, and the weight ratio of green vegetables to mother water is 3:1. The mother water is made to submerge the green vegetables and reach the bottom edge of the kimchi jar. Then, water is added to the jar edge to seal the jar and ferment it at 25°C for 7 days to obtain old jar pickled vegetables.

[0097] Comparative Example 1 Preparation of Traditional Old-style Pickled Cabbage

[0098] 1. Materials

[0099] Brine: Weigh 150 kg of tap water, calculate the amount of salt to be added based on the salinity of the washed vegetables and the equilibrium salinity of the final vegetable water. Since the salinity of the washed vegetables is 7.5 wt%, no salt is added to the water. Then mix 4 kg of sugar and 150 kg of water, dissolve them, and obtain brine. The equilibrium salinity is controlled at 5 wt%.

[0100] 2. Preparation method

[0101] Except that the mother water containing Lactobacillus plantarum KSF001 was replaced by the saline of this comparative example during the second fermentation, the rest was the same as Example 1.

[0102] Comparative Example 2 Preparation of Traditional Old-style Pickled Cabbage

[0103] 1. Materials

[0104] Brine: Weigh 150 kg of tap water, calculate the amount of salt to be added based on the salinity of the washed vegetables and the equilibrium salinity of the final vegetable water. Since the salinity of the washed vegetables is 7.5 wt%, no salt is added to the water. Then mix 4.8 kg of white sugar with 150 kg of water and dissolve them to obtain brine. The equilibrium salinity is controlled at 6 wt%.

[0105] 2. Preparation method

[0106] The process was the same as that of Example 2 except that the mother water containing Lactobacillus plantarum KSF001 was replaced by the saline solution of this comparative example during the second fermentation.

[0107] Comparative Example 3 Preparation of Traditional Old-style Pickled Cabbage

[0108] 1. Materials

[0109] Brine: Weigh 180 kg of pure water, calculate the amount of salt to be added based on the salinity of the washed vegetables and the equilibrium salinity of the final vegetable water. Since the salinity of the washed vegetables is 7.5 wt%, no salt is added to the water. Then mix 4.8 kg of white sugar with 180 kg of water and dissolve them to obtain brine. The equilibrium salinity is controlled at 6.5 wt%.

[0110] 2. Preparation method

[0111] The process was the same as that of Example 3 except that the mother water containing Lactobacillus plantarum KSF001 was replaced by the saline solution of this comparative example during the second fermentation.

[0112] Effect Example 1

[0113] The advantages of the old-style pickled cabbage and the preparation method thereof provided by the embodiments of the present invention are illustrated below by subjecting the old-style pickled cabbage sample prepared in Example 1 of the present invention and the traditional pickled cabbage sample prepared in Comparative Example 1 to sensory evaluation and physical and chemical testing.

[0114] 1. Sensory evaluation Sensory evaluators: consist of 10 members in the laboratory.

[0115] Taste scoring method: The color, shape, aroma, taste and other sensory descriptions of the sauerkraut in each round are given. The five-point preference scale method is used to score the preference of the sauerkraut samples in each round. The specific scoring criteria are: "1" means very dislike and unacceptable; "2" means dislike; "3" means neither dislike nor hate; "4" means like; "5" means very like. The evaluation time for each sample is 60 seconds. During this process, the sensory evaluators are required to score the color, texture, aroma and taste of the sauerkraut. These four indicators are independent indicators and are scored separately without calculating the total score. At least 1 hour before the sensory evaluation experiment, the sensory evaluators are not allowed to eat other food and drinks except purified water. Rinse your mouth with deionized water after each evaluation, and the interval between two evaluations should be greater than 30 seconds.

[0116] Table 1 Sensory evaluation results

[0117]

[0118] From the sensory evaluation results in Table 1, based on the degree of preference, the liking scores of the fermented sauerkraut inoculated with bacteria in Example 1 of the present invention were all higher than those of the comparative example 1 which was not inoculated with bacteria.

[0119] 2. Physical and chemical test results

[0120] (1) Total acid (g / 100g) and pH determination

[0121] Detection method: The total acid of the sauerkraut samples of Example 1 and Comparative Example 1 was determined by the acid-base indicator titration method in accordance with GB / T12456-2021 "Determination of total acid in food, national food safety standard"; the pH value of the sauerkraut samples of Example 1 and Comparative Example 1 was determined by a PHS-3C pH meter in accordance with GB5009.237-2016 "Determination of pH value of food, national food safety standard", and the results are shown in Table 1. Figure 2 and Figure 3 .

[0122] According to the total acid test results of Example 1 and Comparative Example 1, the total acid growth rate of the uninoculated sauerkraut in Comparative Example 1 (blank) was slow and the fermentation speed was slow; the total acid growth rate of the inoculated sauerkraut in Example 1 (inoculated) was fast, the pH dropped rapidly after fermentation, reached a peak value after 5 days and then stabilized, and the fermentation effect was good.

[0123] (2) Microbial count

[0124] Detection method: The lactic acid bacteria count of the sauerkraut samples of Example 1 and Comparative Example 1 was determined according to GB 4789.35-2023 "National Food Safety Standard Food Microbiology Test Lactic Acid Bacteria Test". The yeast count of the sauerkraut samples of Example 1 and Comparative Example 1 was determined according to GB 4789.15-2016 "National Food Safety Standard Food Microbiology Test Mold and Yeast Count". The results are shown in Table 1. Figure 4 .

[0125] according to Figure 4 As shown, the number of lactic acid bacteria in the inoculated sauerkraut of Example 1 (inoculation) is higher than that in the uninoculated sauerkraut of Comparative Example 1 (blank), and the number of yeast in the inoculated sauerkraut of Example 1 (inoculation) is lower than that in the uninoculated sauerkraut of Comparative Example 1. Example 1 (inoculation) is more beneficial to the entire fermentation system.

[0126] (3) Flavor substance content

[0127] Detection method: With reference to GB5009.157-2016 "National Food Safety Standard Determination of Organic Acids in Food", the organic acids in the sauerkraut samples of Example 1 and Comparative Example 1 were determined.

[0128] Specifically, 10 mL of sauerkraut water was centrifuged at 6000 r / min for 5 min, and 1 mL of the supernatant was filtered through a 0.22 μm water filter membrane for high performance liquid chromatography analysis. The analysis conditions were: chromatographic column: Carbomix H-NP10: 8% (10 μm, 7.8 mm × 300 mm), mobile phase A: 2.5 mmol / L H2SO4, column temperature 55 ° C, flow rate 0.6 mL / min, injection volume 10 μL, detector: UV detector UV 210 nm and differential refractometer.

[0129] Preparation of standard curve: Accurately weigh 100 mg of various organic acid, sugar, and alcohol standards and dissolve them in 10 mL of ultrapure water. The concentration of each organic acid is 10 g / L. Pipette 1 mL of various organic acid and sugar alcohol standard stock solutions and mix them evenly. The concentration of the mixed solution is 1 g / L. Pipette 0.0 mL, 0.2 mL, 0.4 mL, 0.8 mL, and 1 mL of the mixed solution into small test tubes respectively, make up to 1 mL of solution, filter with a 0.22 μm filter membrane, and analyze on the machine. Draw a standard curve with the peak area of ​​the chromatogram result as the horizontal axis and the concentration of the standard as the vertical axis. At the same time, add a certain amount of organic acid mixed standard to the sample treatment solution to calculate the absolute recovery rate. Quantitative and qualitative analysis of the samples to be tested: Qualitative analysis is performed by retention time, and quantitative analysis is performed by drawing a standard curve. The results are shown in the table. Figure 5 .

[0130] according to Figure 5The test results show that three organic acids were detected in the pickled cabbage samples of Example 1 (inoculated with bacteria) and Comparative Example 1 (blank), mainly L-lactic acid, the pickled cabbage samples of Comparative Example 1 (blank) had low organic acid content, and the pickled cabbage samples fermented with bacteria in Example 1 (inoculated with bacteria) had higher organic acid content. An appropriate amount of ethanol is beneficial to improving the flavor of kimchi, and the pickled cabbage samples fermented with bacteria in Example 1 (inoculated with bacteria) have a high ethanol content, which is more suitable for the fermentation of traditional pickled cabbage.

[0131] (4) Biogenic amine content

[0132] Detection method: With reference to the liquid chromatography method in GB5009.2008-2016 "Determination of biogenic amines in food" and the determination method of Tang Xiaoman et al. (Tang Xiaoman, Tang Yao, Zhang Qisheng, et al. Formation and degradation analysis of major biogenic amines in Sichuan industrial pickled cowpea [J]. Food and Fermentation Industries, 2019, 45(21): 86-92. DOI: 10.13995 / j.cnki.11) and with slight modifications, the sauerkraut samples of Example 1 and Comparative Example 1 were subjected to biogenic amine determination. The results are shown in Table 1. Figure 6 .

[0133] Specific methods include:

[0134] Extraction of biogenic amines: Accurately weigh 10g of sauerkraut sample and place it in a 50mL centrifuge tube, then add 1.25mL of 1.0mg / mL 1,7-diaminoheptane internal standard solution, then add 15mL of 0.1mol / L HCL to extract the sample, shake for 30min, and centrifuge at 4000r / min for 20min. Take the supernatant and extract the residue again under the same conditions, combine the above two supernatants, and finally dilute to 50mL with 0.1mol / L HCL solution.

[0135] Derivatization of biogenic amines in sauerkraut samples: Take 1.0 mL of biogenic amine standard solution in a 50 mL centrifuge tube, add 200 μL of 2 mol / L sodium hydroxide solution, 300 μL of saturated sodium bicarbonate solution for buffering, then add 2.0 mL of dansyl chloride derivatization agent (10 mg / mL, solvent is acetone), shake and mix well, place in a 40°C dark water bath for 60 min, shake once every 15 min. Add 200 μL of 100 mg / mL proline solution, vortex for 1 min, place in a room temperature dark place for 15 min to terminate the derivatization reaction, add 0.4 g NaCl, vortex for 1 min, add 1 mL of ether, vortex for 30 s, stand for stratification, aspirate the upper organic phase, extract once, combine the organic phases, and place the organic phases in a 45°C water bath to evaporate. Add 1.0 mL of acetonitrile to dissolve the residue, filter the dissolved matter with a 0.22 μm organic membrane, store the filtrate at 4°C in a dark place, and use it for high performance liquid chromatography determination.

[0136] The conditions and methods for derivatization of the sample solution were the same as those for the standard solution.

[0137] Chromatographic detection:

[0138] Chromatographic conditions: Liquid chromatography reference conditions

[0139] The chromatographic column was a C18 column (column length 250 mm, column inner diameter 4.6 mm, column filler particle size 5 μm), UV detection wavelength 254 nm, injection volume 10 μL, column temperature 35 ° C, mobile phase A was 90% acetonitrile

[0140] The mobile phase A was 10% acetonitrile / 90% (0.01 mol / L ammonium acetate solution containing 0.1% acetic acid), and the flow rate was 0.8 mL / min. The gradient elution program is shown in Table 2.

[0141] Table 2 Gradient elution program

[0142] Time / min 0 22 25 32 32.01 37 Mobile phase A / % 60 85 100 100 60 60 Mobile phase B / % 40 15 0 0 40 40

[0143] according to Figure 6 The results show that the content of biogenic amines in the fermented sauerkraut sample in Example 1 (inoculation) is much lower than that in the fermented sauerkraut sample in Comparative Example 1 (blank). Therefore, the sauerkraut sample in Example 1 (inoculation) is safer.

[0144] Effect Example 2

[0145] The advantages of the old pickled cabbage and the preparation method provided by the embodiments of the present invention are illustrated below by subjecting the old pickled cabbage sample prepared in Example 2 and the traditional pickled cabbage sample prepared in Comparative Example 2 to multiple rounds of fermentation and then conducting physical and chemical tests.

[0146] 1. Determination of total acid (g / 100g)

[0147] Detection method: Same as the determination method of total acid in Example 1, the results are shown in Figure 7 .

[0148] according to Figure 7 The results show that the total acid content in the sauerkraut sample of Example 2 (inoculated with bacteria) increased more rapidly than that in Comparative Example 2 (blank), which was consistent with the change trend of the first round. The total acid content in the second round was higher, exceeding 0.8g / 100g when mature (when taken out of the jar).

[0149] 2. Microbial Count

[0150] Detection method: Same as the microbial count in Example 1, the results are shown in Figure 8 .

[0151] according to Figure 8The results show that compared with the sauerkraut sample of Comparative Example 2 (blank), the sauerkraut sample of Example 2 (inoculated) has a higher number of lactic acid bacteria and a lower number of yeast in both rounds, which is more beneficial to the entire fermentation system.

[0152] Effect Example 3

[0153] The advantages of the Laotan pickled cabbage and the preparation method provided by the embodiments of the present invention are illustrated below by subjecting the Laotan pickled cabbage sample prepared in Example 3 and the traditional pickled cabbage sample prepared in Comparative Example 3 to multiple rounds of fermentation and then conducting physical and chemical tests.

[0154] 1. Determination of total acid (g / 100g)

[0155] Detection method: Same as the determination method of total acid in Example 1, the results are shown in Fig. 9 .

[0156] according to Fig. 9 The results show that the total acid content in the sauerkraut sample of Example 3 (inoculated with bacteria) increases more rapidly than that in Comparative Example 3 (blank), the total acid content in the sauerkraut sample of Example 3 (inoculated with bacteria) is higher, the total acid content in the second round is higher, and the total acid content of the sauerkraut sample of Example 3 (inoculated with bacteria) exceeds 0.9g / 100g when mature.

[0157] 2. Microbial Count

[0158] Detection method: Same as the microbial count in Example 1, the results are shown in Fig.10 .

[0159] according to Fig.10 The results show that compared with the sauerkraut sample of Comparative Example 3 (blank), the sauerkraut sample of Example 3 (inoculated) has a higher number of lactic acid bacteria and a lower number of yeast in both rounds, which is more beneficial to the entire fermentation system.

[0160] Effect Example 4

[0161] The advantages of the old-style pickled cabbage and the preparation method provided by the embodiments of the present invention are illustrated below by applying the pickled cabbage preparation processes of Example 1 and Comparative Example 1 to three different enterprises, performing multiple rounds of fermentation, and then conducting physical and chemical tests.

[0162] 1. Determination of total acid (g / 100g)

[0163] Detection method: Same as the determination method of total acid in Example 1, the results are shown in Fig.11 .

[0164] according to Fig.11The results show that when the sauerkraut preparation process of Example 1 (inoculation) was applied to three different companies, the total acid content after each round of fermentation could be maintained above 0.7g / 100g; when the sauerkraut preparation process of Comparative Example 1 (blank) was applied to three different companies, the total acid content in each round of fermentation was unstable and varied greatly.

[0165] 2. Amino Acid Determination

[0166] Detection method: Weigh 5.0g of each of the sauerkraut samples of Example 1 and Comparative Example 1, add 5mL of ultrapure water to mix, place in a constant temperature water bath at 50°C for 30min, centrifuge and take 5mL of supernatant; place 100μL of the treated supernatant and amino acid standard in 5mL test tubes, add 200μL of a derivatizing agent (mixed from 1600μL of acetonitrile, 200μL of triethylamine and 20μL of phenyl isothiocyanate), mix and let stand for 60min. Add 2mL of ultrapure water and 1mL of n-hexane to mix, remove the upper solution, add 1mL of n-hexane and vortex for 1min, let stand at room temperature for 10min, take the lower solution and filter through a 0.22μm water filter for later use. The detection conditions are as follows: chromatographic column: Yuedan Ultimate Amino Aci chromatographic column (4.6mmx250 mm, 5μm), mobile phase A is 0.1mol / L sodium acetate (pH 6.50): acetonitrile = 93:7, mobile phase B is ultrapure water: acetonitrile = 20:80, column temperature: 40℃, flow rate: 1.0mL / min, injection volume: 10μL, detector: UV210 nm, results are shown in Fig.12 .

[0167] according to Fig.12 The results show that the sauerkraut preparation processes of Example 1 (inoculation) and Comparative Example 1 (blank) were respectively applied to three different companies. Compared with Comparative Example 1 (blank), the content of essential amino acids for human body in the sauerkraut prepared by Example 1 (inoculation) was significantly increased.

[0168] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A traditional pickled vegetable, characterized in that: The old-style pickled cabbage is obtained by fermenting Lactobacillus plantarum KSF001, and the Lactobacillus plantarum KSF001 was deposited in the China General Microbiological Culture Collection Center on June 14, 2024, with a deposit number of: CGMCC No: 30957.

2. A method for preparing old pickled mustard greens, characterized in that: For preparing the old pickled mustard greens as claimed in claim 1, the preparation method comprising: The first fermentation step: adding salt to fresh green vegetables for sealed fermentation to obtain salt-cured mature green vegetables; the washing step: washing the salt-cured mature green vegetables, draining them to obtain washed green vegetables, and measuring the salinity of the washed green vegetables; The second fermentation step: placing the washed green vegetables in a pickle jar, adding mother water containing the Lactobacillus plantarum KSF001, and fermenting to obtain the old pickled vegetables.

3. The method for preparing old pickled mustard greens as claimed in claim 2, characterized in that: The first fermentation step comprises: Fresh green vegetables that meet food safety requirements are added with iodine-free salt, wherein the weight ratio of the fresh green vegetables to the iodine-free salt is 100:8-16. The vegetables are placed in a pickling tank in a layer of fresh green vegetables and a layer of iodine-free salt, and sealed and fermented for more than 3 months.

4. The method for preparing old pickled mustard greens as claimed in claim 2, characterized in that: The cleaning step comprises: The salted mature green vegetables are washed by a bubbling washing machine and drained to obtain washed green vegetables. The salinity of the washed green vegetables is measured. The salinity of the washed green vegetables is controlled to be 5wt% to 8wt%.

5. The method for preparing traditional pickled mustard greens as claimed in claim 2, characterized in that: The mother water containing the Lactobacillus plantarum KSF001 is prepared by the following method: Weigh 140kg to 165kg of pure water or tap water, calculate the amount of salt to be added according to the salinity of the washed green vegetables and the equilibrium salinity of the final vegetable water, then mix and dissolve the salt, 4kg to 7kg of white sugar and 140kg to 165kg of water to obtain salt water, wherein the equilibrium salinity is controlled within 5wt% to 6.5wt%; The activated Lactobacillus plantarum KSF001 is added to the salt water to obtain mother water containing the Lactobacillus plantarum KSF001.

6. The method for preparing traditional pickled mustard greens as claimed in claim 5, characterized in that: The activated Lactobacillus plantarum KSF001 is obtained by the following method: 100 mL of pure water, 1 g of salt and 1 g of white sugar were placed in a conical flask, and 5 g of the Lactobacillus plantarum KSF001 was added after shaking and dissolving, and covered with a latex stopper after shaking, and placed in a 37° C. incubator for 1 hour to obtain the activated Lactobacillus plantarum KSF001.

7. The method for preparing traditional pickled mustard greens as claimed in claim 2, characterized in that: The second fermentation step comprises: The cleaned green vegetables are placed in a kimchi jar, and the green vegetables are fixed at the mouth of the kimchi jar with bamboo strips. After fixation, mother water containing Lactobacillus plantarum KSF001 is added to submerge the green vegetables and reach the bottom edge of the kimchi jar. Then, water is added to seal the jar for fermentation to obtain the old-style pickled vegetables.

8. The method for preparing traditional pickled mustard greens as claimed in claim 7, characterized in that: In the second fermentation step, the weight ratio of the green vegetables to the mother water is 2.5-3.5:

1.

9. The method for preparing traditional pickled mustard greens as claimed in claim 2, characterized in that: The green vegetables are large-leaf mustard greens.

10. The method for preparing traditional pickled mustard greens according to claim 7, characterized in that: In the second fermentation step, the fermentation temperature is 20°C to 30°C.

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