A preparation method of low-salt lactic acid bacteria fermented pickled cabbage

Abstract

The present application relates to a kind of preparation methods of low-salt lactic acid bacteria fermented pickled vegetable, belong to the technical field of fermented vegetable processing, comprising the following steps: step S1, lactic acid bacteria is put into pre-activation culture medium, keep environmental temperature 20-25 ℃ constant temperature culture, activation duration 60-120 min, obtain activated lactic acid bacteria bacterial liquid;Step S2, green vegetables, salt, fermentation slow-release granules are uniformly mixed, then water is divided into three equal parts, and is evenly sprayed to green vegetables mixture in three times, after each time of spraying water, continue stirring 3 min, obtain mixed green vegetable material.The low-salt lactic acid bacteria fermented pickled vegetable prepared according to the method of the present application compared with traditional salted pickled vegetable, total acid is moderate, and salt content is lower, therefore, the preparation method of low-salt lactic acid bacteria fermented pickled vegetable by lactic acid bacteria is involved in fermentation is better, by using the amount of salt is reduced, in the production process, the discharged salt is also less, the maturation period of pickled vegetable is shortened, at the same time, low-salt lactic acid bacteria fermented pickled vegetable removes salted flavor, and the flavor of pickled vegetable is improved.

Description

Technical Field

[0001] This invention belongs to the field of fermented vegetable processing technology, specifically relating to a method for preparing sauerkraut fermented with low-salt lactic acid bacteria. Background Technology

[0002] Sauerkraut is highly favored by the market due to its unique lactic acid fermentation flavor. It is a high-volume processed product among pickled vegetables. Currently, most sauerkraut producers still use the traditional high-salt natural fermentation process for processing. This process relies on high concentrations of salt to achieve short-term antibacterial effects and is a mature processing model that has been widely used in the industry for a long time.

[0003] Traditional high-salt fermentation processes involve a high proportion of salt added, resulting in a large amount of salt remaining in the production waste liquid after fermentation. This leads to excessive salt content in the wastewater, significantly increasing the load on downstream wastewater treatment equipment and environmental treatment costs. At the same time, the high-salt environment inhibits the normal proliferation and metabolism of lactic acid bacteria, resulting in slow fermentation start-up, a long overall maturation cycle, and low production turnover efficiency. The high-salt system also masks the natural lactic acid aroma produced by lactic acid bacteria metabolism, giving the finished product a heavy, salty, and astringent off-flavor, weakening the pure fermented flavor of the sauerkraut itself, and resulting in significant shortcomings in the product's taste and flavor quality. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing low-salt lactic acid bacteria fermented sauerkraut in order to solve the above-mentioned problems.

[0005] The present invention achieves the above objectives through the following technical solutions:

[0006] This invention provides a method for preparing low-salt lactic acid bacteria fermented sauerkraut, comprising the following steps:

[0007] Step S1: Add lactic acid bacteria to the pre-activated culture medium, maintain the ambient temperature at 20-25℃ for constant temperature culture, and activate for 60-120 minutes to obtain activated lactic acid bacteria solution;

[0008] Step S2: After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0009] Step S3: Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and pack into a sealed fermentation tank;

[0010] Step S4: Seal the fermentation tank, control the fermentation temperature at 18-24℃, and ferment for 8-18 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0011] As a further optimization of the present invention, the raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include:

[0012] 100-110 parts green vegetables, 9-9.9 parts salt, 2-6 parts water, 0.03-0.05 parts lactic acid bacteria, 8-15 parts pre-activated culture medium, 0.63-1.21 parts fermentation slow-release granules.

[0013] As a further optimization of the present invention, the raw materials for preparing the pre-activated culture medium, by weight, include: 80-90 parts water, 8-12 parts food-grade glucose, and 15-22 parts malt extract.

[0014] As a further optimization of the present invention, the preparation process of the pre-activated culture medium is as follows:

[0015] (a) Add water to the mixing tank, then add food-grade glucose, control the temperature inside the tank to 20-25℃, control the stirring speed to 100-300rpm, and stir for 8-15 minutes to obtain a transparent sugar solution.

[0016] (ii) Add malt extract stock solution to the mixing tank, mix and stir with transparent sugar solution, control the stirring time to 5-10 min, control the temperature inside the tank to 20-25℃, control the stirring speed to 200-330 rpm, and obtain composite culture solution;

[0017] (iii) Control the temperature inside the tank to 20-25℃, stir the composite culture medium at a speed of 50-80 rpm, add food-grade citric acid to adjust the pH to 5.5-6.5, then stop stirring to obtain the pre-pH culture medium;

[0018] (iv) Let the pre-pH culture medium stand for 8-24 minutes to obtain the pre-activated culture medium.

[0019] As a further optimization of the present invention, the raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material, 12-16 parts grain mixture juice, 3-10 parts fig pectin, 0.8-2.5 parts food-grade L-calcium lactate aqueous solution, and 40-130 parts potato resistant starch.

[0020] Specifically, the core material is defatted and dephenolized cottonseed protein powder;

[0021] The grain mixture juice, by weight, includes millet juice and corn juice in a 1:1 mass ratio.

[0022] As a further optimization of the present invention, the preparation process of the grain mixture juice is as follows:

[0023] (a) Add the millet juice and corn juice to the vacuum concentration tank and stir to mix well;

[0024] (ii) Control the temperature inside the vacuum concentration tank to 50-60℃ and the vacuum degree to -0.06~-0.08MPa, and stir at a speed of 100-120rpm until the solid content of the mixture reaches 40%-50% of the concentrate.

[0025] (iii) Cool the concentrate to 15-29℃ and filter it using a 120-mesh filter to obtain the filtrate;

[0026] (iv) The filtrate is transferred into a sealed storage tank and left to stand at 20-24℃ for 15-30 minutes to obtain grain mixture juice.

[0027] As a further optimization of the present invention, the preparation process of the fermentation slow-release granules is as follows:

[0028] (a) Divide the core material into three equal parts by weight and prepare controlled-release particles with different coating layers in batches:

[0029] Take one portion of core material and place it in the pellet mill. Use a 0.12-0.15MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surface is evenly moistened and there is no dry material left. Then add potato resistant starch powder into the pellet mill to complete one round of coating. Take another portion of core material and place it in the pellet mill. Use a 0.12-0.15MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surface is evenly moistened and there is no dry material left. Then add potato resistant starch powder into the pellet mill to complete two rounds of coating. Take the last portion of core material and place it in the pellet mill. Use a 0.12-0.15MPa atomizing nozzle to spray the mixture juice. The grain mixture juice is sprayed at a uniform speed until all dry powder surfaces are evenly moistened and free of dry material. Then, potato resistant starch powder is added to the granulator to complete three rounds of coating. Fig pectin is sprayed onto the three coated core materials at a pressure of 0.10-0.13 MPa, and the mixture is rolled and bonded to form a continuous coating film. Finally, food-grade L-calcium lactate aqueous solution is sprayed at a single spray amount of 0.4%-0.6% of the total mass of the core material. Then, the mixture is sealed and left to stand at room temperature (20-24℃) for 15 minutes, and then transferred to a vacuum drying oven and dried at 40-42℃ until the moisture content of the material is 5% by mass, resulting in one-layer slow-release granules, two-layer slow-release granules, and three-layer slow-release granules.

[0030] (ii) Mix one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules evenly to obtain fermentation slow-release granules.

[0031] As a further optimization of the present invention, the fig pectin contains fig powder and water in a mass ratio of 3%-4%, and the food-grade L-calcium lactate aqueous solution has a mass concentration of 4%-5%.

[0032] The beneficial effects of the present invention are as follows: Compared with traditional salted sauerkraut, the low-salt lactic acid bacteria fermented sauerkraut prepared according to the method of the present invention has a moderate total acidity and a lower salt content. Therefore, the preparation method of low-salt lactic acid bacteria fermented sauerkraut with lactic acid bacteria participation in fermentation is superior. The amount of salt used is reduced, less salt is emitted during the production process, the sauerkraut maturation cycle is shortened, and the low-salt lactic acid bacteria fermented sauerkraut removes the salt flavor, thereby improving the flavor of the sauerkraut.

[0033] A pre-activated culture medium is prepared by mixing pure water, food-grade glucose and malt extract. The ratio of each raw material is scientifically adapted to the growth requirements of lactic acid bacteria. Before fermentation, the lactic acid bacteria are placed in this culture medium at a constant temperature for pre-activation, which can quickly awaken dormant bacteria, significantly increase the number of live bacteria and the metabolic activity of the bacteria, accelerate the fermentation start-up rate of green vegetables, and greatly improve the overall fermentation and processing efficiency.

[0034] Using defatted and dephenolized cottonseed protein powder as the nutrient core material, combined with grain mixed juice, fig pectin, and potato resistant starch, and coated with food-grade L-calcium lactate aqueous solution, gradient-layer fermentation slow-release granules are prepared. These granules can release carbon and nitrogen nutrients in stages and stably throughout the anaerobic fermentation process of sauerkraut, continuously providing growth substrates for lactic acid bacteria, maintaining a high level of lactic acid bacteria activity throughout the process, ensuring a stable and sufficient fermentation process, and effectively improving the fermentation quality of sauerkraut. Detailed Implementation

[0035] The present application will now be described in further detail. It should be noted that the following specific embodiments are only used to further illustrate the present application and should not be construed as limiting the scope of protection of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application based on the above application content.

[0036] Unless otherwise specified, all methods used in this invention are conventional methods known to those skilled in the art, and all reagents and materials used are commercially available products.

[0037] In this invention:

[0038] The water is pure water;

[0039] Preparation of fig pectin: Mix dried fig powder with water until the mass ratio of dried fig powder to water is 3%-4%;

[0040] The content of the food-grade L-calcium lactate aqueous solution is 5 wt%.

[0041] Example 1

[0042] A method for preparing low-salt lactic acid bacteria fermented sauerkraut includes the following steps:

[0043] The preparation process of the pre-activated culture medium is as follows: (i) Water is added to a mixing tank, then food-grade glucose is added, the temperature inside the tank is controlled at 20°C, the stirring speed is controlled at 100 rpm, and the mixture is stirred for 8 minutes to obtain a transparent sugar solution; (ii) Malt extract is added to the mixing tank and mixed with the transparent sugar solution, the stirring time is controlled at 5 minutes, the temperature inside the tank is controlled at 20°C, and the stirring speed is controlled at 200 rpm to obtain a composite culture solution; (iii) The temperature inside the tank is controlled at 20°C, the composite culture solution is stirred at 50 rpm, food-grade citric acid is added dropwise to adjust the pH to 5.5, and then the stirring is stopped to obtain a pre-pH culture solution; (iv) The pre-pH culture solution is allowed to stand for 8 minutes to obtain a pre-activated culture medium.

[0044] Lactic acid bacteria were added to a pre-activated culture medium and cultured at a constant temperature of 20°C for 60 minutes to obtain activated lactic acid bacteria solution.

[0045] The preparation process of the grain mixture juice is as follows: (i) Millet juice and corn juice are put into a vacuum concentration tank and stirred until well mixed; (ii) The temperature inside the vacuum concentration tank is controlled at 50°C and the vacuum degree is -0.06MPa, and the mixture is stirred at 100rpm until the solid content of the mixture juice reaches 40% concentration; (iii) The concentration is cooled to 15°C and filtered using a 120-mesh filter to obtain filtrate; (iv) The filtrate is transferred to a sealed storage tank and left to stand at 20°C for 15 minutes to obtain grain mixture juice.

[0046] The preparation process of the fermented slow-release granules is as follows: (I) Divide the core material into 3 equal parts by weight and prepare slow-release granules with different coating layers in batches: Take one part of the core material and place it in a pellet mill. Use a 0.12MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete one round of coating. Take another part of the core material and place it in a pellet mill. Use a 0.12MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. Take the last part of the core material and place it in a pellet mill. Use a 0.12MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. Spray the grain mixture juice evenly with the nozzle until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the granulator to complete 3 rounds of coating. Spray fig pectin on the three coated core materials with a pressure of 0.10MPa and roll them together to form a continuous coating film. Finally, spray food-grade L-calcium lactate aqueous solution at a single spray amount of 0.4% of the total mass of the core material. Then, let it stand in a sealed container at room temperature of 20℃ for 15 minutes, transfer it to a vacuum drying oven, and dry it at 40℃ until the moisture content of the material is 5% to obtain one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules. (II) Mix the one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules evenly to obtain fermented slow-release granules.

[0047] After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0048] Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and then pack into a sealed fermentation tank.

[0049] A sealed fermentation tank was used to control the fermentation temperature at 18℃ for 8 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0050] The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 100 parts green vegetables, 9 parts salt, 2 parts water, 0.03 parts lactic acid bacteria, 8 parts pre-activated culture medium, and 0.63 parts fermentation slow-release granules.

[0051] The raw materials for preparing the pre-activated culture medium, by weight, include: 80 parts water, 8 parts food-grade glucose, and 15 parts malt extract.

[0052] The raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material (defatted and dephenolized cottonseed protein powder), 12 parts mixed grain juice (millet juice and corn juice in a mass ratio of 1:1), 3 parts fig pectin (fig pectin with a mass ratio of fig powder to water of 3%), 0.8 parts food-grade L-calcium lactate aqueous solution (mass concentration of 4%), and 40 parts potato resistant starch.

[0053] Example 2

[0054] A method for preparing low-salt lactic acid bacteria fermented sauerkraut includes the following steps:

[0055] The preparation process of the pre-activated culture medium is as follows: (i) Water is added to a mixing tank, then food-grade glucose is added, the temperature inside the tank is controlled at 22℃, the stirring speed is controlled at 200 rpm, and the mixture is stirred for 11 min to obtain a transparent sugar solution; (ii) Malt extract is added to the mixing tank and mixed with the transparent sugar solution, the stirring time is controlled at 7 min, the temperature inside the tank is controlled at 22℃, and the stirring speed is controlled at 265 rpm to obtain a composite culture solution; (iii) The temperature inside the tank is controlled at 22℃, the composite culture solution is stirred at 65 rpm, food-grade citric acid is added dropwise to adjust the pH to 6, and then the stirring is stopped to obtain a pre-pH culture solution; (iv) The pre-pH culture solution is allowed to stand for 16 min to obtain a pre-activated culture medium;

[0056] Lactic acid bacteria were added to a pre-activated culture medium and cultured at a constant temperature of 22℃ for 90 minutes to obtain activated lactic acid bacteria solution.

[0057] The preparation process of the grain mixture juice is as follows: (i) Millet juice and corn juice are put into a vacuum concentration tank and stirred until well mixed; (ii) The temperature inside the vacuum concentration tank is controlled at 55℃ and the vacuum degree is -0.07MPa, and the mixture is stirred at 110rpm until the solid content of the mixture juice reaches 45% concentration; (iii) The concentration is cooled to 22℃ and filtered using a 120-mesh filter to obtain filtrate; (iv) The filtrate is transferred to a sealed storage tank and left to stand at 22℃ for 22min to obtain concentrated grain mixture juice.

[0058] The preparation process of the fermented slow-release granules is as follows: (I) Divide the core material into 3 equal parts by weight and prepare slow-release granules with different coating layers in batches: Take one part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete one round of coating. Take another part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. Take the last part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. a. Atomizing nozzle, uniformly spray the grain mixture juice until all dry powder surfaces are evenly moistened and no dry material remains. Then, add potato resistant starch dry powder into the granulator to complete 3 rounds of coating. Spray fig pectin onto the three coated core materials at a pressure of 0.115 MPa, roll and bond to form a continuous coating film. Finally, spray food-grade L-calcium lactate aqueous solution at a single spray amount of 0.5% of the total mass of the core material. Then, let it stand in a sealed container at room temperature of 22℃ for 15 minutes and transfer it to a vacuum drying oven. Dry it at 41℃ until the moisture content of the material is 5% to obtain one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules. (ii) Mix the one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules evenly to obtain fermented slow-release granules.

[0059] After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0060] Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and then pack into a sealed fermentation tank.

[0061] A sealed fermentation tank was used to control the fermentation temperature at 21℃ for 13 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0062] The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 105 parts green vegetables, 9.45 parts salt, 4 parts water, 0.04 parts lactic acid bacteria, 11.5 parts pre-activated culture medium, and 0.92 parts fermentation slow-release granules.

[0063] The raw materials for preparing the pre-activated culture medium, by weight, include: 85 parts water, 10 parts food-grade glucose, and 18.5 parts malt extract.

[0064] The raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material (defatted and dephenolized cottonseed protein powder), 14 parts mixed grain juice (millet juice and corn juice in a mass ratio of 1:1), 6.5 parts fig pectin (fig pectin with a mass ratio of fig dry powder to water of 3.5%), 1.4 parts food-grade L-calcium lactate aqueous solution (mass concentration of 4.5%), and 85 parts potato resistant starch.

[0065] Example 3

[0066] A method for preparing low-salt lactic acid bacteria fermented sauerkraut includes the following steps:

[0067] The preparation process of the pre-activated culture medium is as follows: (i) Water is added to a mixing tank, then food-grade glucose is added, the temperature inside the tank is controlled at 25°C, the stirring speed is controlled at 300 rpm, and the mixture is stirred for 15 min to obtain a transparent sugar solution; (ii) Malt extract is added to the mixing tank and mixed with the transparent sugar solution, the stirring time is controlled at 10 min, the temperature inside the tank is controlled at 25°C, and the stirring speed is controlled at 330 rpm to obtain a composite culture solution; (iii) The temperature inside the tank is controlled at 25°C, the composite culture solution is stirred at 80 rpm, food-grade citric acid is added dropwise to adjust the pH to 6.5, and then the stirring is stopped to obtain a pre-pH culture solution; (iv) The pre-pH culture solution is allowed to stand for 24 min to obtain a pre-activated culture medium.

[0068] Lactic acid bacteria were added to a pre-activated culture medium and cultured at a constant temperature of 25°C for 120 minutes to obtain activated lactic acid bacteria solution.

[0069] The preparation process of the grain mixture juice is as follows: (i) Millet juice and corn juice are put into a vacuum concentration tank and stirred until well mixed; (ii) The temperature inside the vacuum concentration tank is controlled at 60℃ and the vacuum degree is -0.08MPa, and the mixture is stirred at 120rpm until the solid content of the mixture juice reaches 50% concentration; (iii) The concentration is cooled to 29℃ and filtered using a 120-mesh filter to obtain filtrate; (iv) The filtrate is transferred to a sealed storage tank and left to stand at 24℃ for 30min to obtain concentrated grain mixture juice.

[0070] The preparation process of the fermented slow-release granules is as follows: (I) Divide the core material into 3 equal parts by weight and prepare slow-release granules with different coating layers in batches: Take one part of the core material and place it in a pellet mill. Use a 0.15MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete one round of coating. Take another part of the core material and place it in a pellet mill. Use a 0.15MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. Take the last part of the core material and place it in a pellet mill. Use a 0.15MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. Spray the grain mixture juice evenly with the nozzle until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the granulator to complete 3 rounds of coating. Spray fig pectin on the three coated core materials with a 0.13MPa pressure and roll to form a continuous coating film. Finally, spray food-grade L-calcium lactate aqueous solution with a single spray amount of 0.6% of the total mass of the core material. Then, let it stand in a sealed container at room temperature of 24℃ for 15 minutes, transfer it to a vacuum drying oven, and dry it at 42℃ until the moisture content of the material is 5% to obtain one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules. (II) Mix the one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules evenly to obtain fermented slow-release granules.

[0071] After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0072] Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and then pack into a sealed fermentation tank.

[0073] A sealed fermentation tank was used to control the fermentation temperature at 24℃ for 18 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0074] The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 110 parts green vegetables, 9.9 parts salt, 6 parts water, 0.05 parts lactic acid bacteria, 15 parts pre-activated culture medium, and 1.21 parts fermentation slow-release granules.

[0075] The raw materials for preparing the pre-activated culture medium, by weight, include: 90 parts water, 12 parts food-grade glucose, and 22 parts malt extract.

[0076] The raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material (defatted and dephenolized cottonseed protein powder), 16 parts mixed grain juice (millet juice and corn juice in a mass ratio of 1:1), 10 parts fig pectin (fig pectin with a mass ratio of 4% fig powder to water), 2.5 parts food-grade L-calcium lactate aqueous solution (mass concentration of 5%), and 130 parts potato resistant starch.

[0077] Comparative Example 1

[0078] A method for preparing salted sauerkraut includes the following steps:

[0079] Put the green vegetables, salt, and water into a sealed fermentation jar;

[0080] A sealed fermentation tank was used to control the fermentation temperature at 21℃ for 13 days to obtain salted sauerkraut.

[0081] The raw materials for preparing the salted sauerkraut, by weight, include: 105 parts of green vegetables, 13.6 parts of salt, and 4 parts of water.

[0082] Comparative Example 2

[0083] A method for preparing low-salt lactic acid bacteria fermented sauerkraut includes the following steps:

[0084] The preparation process of the grain mixture juice is as follows: (i) Millet juice and corn juice are put into a vacuum concentration tank and stirred until well mixed; (ii) The temperature inside the vacuum concentration tank is controlled at 55℃ and the vacuum degree is -0.07MPa, and the mixture is stirred at 110rpm until the solid content of the mixture juice reaches 45% concentration; (iii) The concentration is cooled to 22℃ and filtered using a 120-mesh filter to obtain filtrate; (iv) The filtrate is transferred to a sealed storage tank and left to stand at 22℃ for 22min to obtain concentrated grain mixture juice.

[0085] The preparation process of the fermented slow-release granules is as follows: (I) Divide the core material into 3 equal parts by weight and prepare slow-release granules with different coating layers in batches: Take one part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete one round of coating. Take another part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. Take the last part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. a. Atomizing nozzle, uniformly spray the grain mixture juice until all dry powder surfaces are evenly moistened and no dry material remains. Then, add potato resistant starch dry powder into the granulator to complete 3 rounds of coating. Spray fig pectin onto the three coated core materials at a pressure of 0.115 MPa, roll and bond to form a continuous coating film. Finally, spray food-grade L-calcium lactate aqueous solution at a single spray amount of 0.5% of the total mass of the core material. Then, let it stand in a sealed container at room temperature of 22℃ for 15 minutes and transfer it to a vacuum drying oven. Dry it at 41℃ until the moisture content of the material is 5% to obtain one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules. (ii) Mix the one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules evenly to obtain fermented slow-release granules.

[0086] After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0087] Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and then pack into a sealed fermentation tank.

[0088] A sealed fermentation tank was used to control the fermentation temperature at 21℃ for 13 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0089] The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 115.08 parts of green vegetables, 10.3572 parts of salt, 4.384 parts of water, 0.04384 parts of lactic acid bacteria, and 1.04496 parts of fermentation slow-release granules.

[0090] The raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material (defatted and dephenolized cottonseed protein powder), 14 parts mixed grain juice (millet juice and corn juice in a mass ratio of 1:1), 6.5 parts fig pectin (fig pectin with a mass ratio of fig dry powder to water of 3.5%), 1.4 parts food-grade L-calcium lactate aqueous solution (mass concentration of 4.5%), and 85 parts potato resistant starch.

[0091] Comparative Example 3

[0092] A method for preparing low-salt lactic acid bacteria fermented sauerkraut includes the following steps:

[0093] The preparation process of the pre-activated culture medium is as follows: (i) Water is added to a mixing tank, then food-grade glucose is added, the temperature inside the tank is controlled at 22℃, the stirring speed is controlled at 200 rpm, and the mixture is stirred for 11 min to obtain a transparent sugar solution; (ii) Malt extract is added to the mixing tank and mixed with the transparent sugar solution, the stirring time is controlled at 7 min, the temperature inside the tank is controlled at 22℃, and the stirring speed is controlled at 265 rpm to obtain a composite culture solution; (iii) The temperature inside the tank is controlled at 22℃, the composite culture solution is stirred at 65 rpm, food-grade citric acid is added dropwise to adjust the pH to 6, and then the stirring is stopped to obtain a pre-pH culture solution; (iv) The pre-pH culture solution is allowed to stand for 16 min to obtain a pre-activated culture medium;

[0094] Lactic acid bacteria were added to a pre-activated culture medium and cultured at a constant temperature of 22℃ for 90 minutes to obtain activated lactic acid bacteria solution.

[0095] After mixing the green vegetables and salt evenly, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0096] Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and then pack into a sealed fermentation tank.

[0097] A sealed fermentation tank was used to control the fermentation temperature at 21℃ for 13 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0098] The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 105.74 parts of green vegetables, 9.52 parts of salt, 4.028 parts of water, 0.042 parts of lactic acid bacteria, and 11.58 parts of pre-activated culture medium.

[0099] The raw materials for preparing the pre-activated culture medium, by weight, include: 85 parts water, 10 parts food-grade glucose, and 18.5 parts malt extract.

[0100] Comparative Example 4

[0101] A method for preparing low-salt lactic acid bacteria fermented sauerkraut includes the following steps:

[0102] The preparation process of the pre-activated culture medium is as follows: (i) Water is added to a mixing tank, then food-grade glucose is added, the temperature inside the tank is controlled at 22℃, the stirring speed is controlled at 200 rpm, and the mixture is stirred for 11 min to obtain a transparent sugar solution; (ii) Malt extract is added to the mixing tank and mixed with the transparent sugar solution, the stirring time is controlled at 7 min, the temperature inside the tank is controlled at 22℃, and the stirring speed is controlled at 265 rpm to obtain a composite culture solution; (iii) The temperature inside the tank is controlled at 22℃, the composite culture solution is stirred at 65 rpm, food-grade citric acid is added dropwise to adjust the pH to 6, and then the stirring is stopped to obtain a pre-pH culture solution; (iv) The pre-pH culture solution is allowed to stand for 16 min to obtain a pre-activated culture medium;

[0103] Lactic acid bacteria were added to a pre-activated culture medium and cultured at a constant temperature of 22℃ for 90 minutes to obtain activated lactic acid bacteria solution.

[0104] The preparation process of the grain mixture juice is as follows: (i) Millet juice and corn juice are put into a vacuum concentration tank and stirred until well mixed; (ii) The temperature inside the vacuum concentration tank is controlled at 55℃ and the vacuum degree is -0.07MPa, and the mixture is stirred at 110rpm until the solid content of the mixture juice reaches 45% concentration; (iii) The concentration is cooled to 22℃ and filtered using a 120-mesh filter to obtain filtrate; (iv) The filtrate is transferred to a sealed storage tank and left to stand at 22℃ for 22min to obtain concentrated grain mixture juice.

[0105] The preparation process of the fermented slow-release granules is as follows: (I) Divide the core material into two equal parts by weight and prepare slow-release granules with different coating layers in batches: Take one part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. Take the other part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete two rounds of coating. Potato resistant starch powder was added to the granulator to complete three rounds of coating; fig pectin was sprayed onto the two coated core materials at a pressure of 0.115 MPa and rolled to form a continuous coating film. Finally, food-grade L-calcium lactate aqueous solution was sprayed at a single spray amount of 0.5% of the total mass of the core material. Then, the mixture was placed in a sealed container at room temperature of 22°C for 15 minutes and then transferred to a vacuum drying oven. The material was dried at 41°C until the moisture content was 5% to obtain two-layer slow-release granules and three-layer slow-release granules; (II) The two-layer slow-release granules and three-layer slow-release granules were mixed evenly to obtain fermented slow-release granules.

[0106] After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0107] Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and then pack into a sealed fermentation tank.

[0108] A sealed fermentation tank was used to control the fermentation temperature at 21℃ for 13 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0109] The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 105 parts green vegetables, 9.45 parts salt, 4 parts water, 0.04 parts lactic acid bacteria, 11.5 parts pre-activated culture medium, and 0.92 parts fermentation slow-release granules.

[0110] The raw materials for preparing the pre-activated culture medium, by weight, include: 85 parts water, 10 parts food-grade glucose, and 18.5 parts malt extract.

[0111] The raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material (defatted and dephenolized cottonseed protein powder), 14 parts mixed grain juice (millet juice and corn juice in a mass ratio of 1:1), 6.5 parts fig pectin (fig pectin with a mass ratio of fig dry powder to water of 3.5%), 1.4 parts food-grade L-calcium lactate aqueous solution (mass concentration of 4.5%), and 85 parts potato resistant starch.

[0112] Comparative Example 5

[0113] A method for preparing low-salt lactic acid bacteria fermented sauerkraut includes the following steps:

[0114] The preparation process of the pre-activated culture medium is as follows: (i) Water is added to a mixing tank, then food-grade glucose is added, the temperature inside the tank is controlled at 22℃, the stirring speed is controlled at 200 rpm, and the mixture is stirred for 11 min to obtain a transparent sugar solution; (ii) Malt extract is added to the mixing tank and mixed with the transparent sugar solution, the stirring time is controlled at 7 min, the temperature inside the tank is controlled at 22℃, and the stirring speed is controlled at 265 rpm to obtain a composite culture solution; (iii) The temperature inside the tank is controlled at 22℃, the composite culture solution is stirred at 65 rpm, food-grade citric acid is added dropwise to adjust the pH to 6, and then the stirring is stopped to obtain a pre-pH culture solution; (iv) The pre-pH culture solution is allowed to stand for 16 min to obtain a pre-activated culture medium;

[0115] Lactic acid bacteria were added to a pre-activated culture medium and cultured at a constant temperature of 22℃ for 90 minutes to obtain activated lactic acid bacteria solution.

[0116] The preparation process of the grain mixture juice is as follows: (i) Millet juice and corn juice are put into a vacuum concentration tank and stirred until well mixed; (ii) The temperature inside the vacuum concentration tank is controlled at 55℃ and the vacuum degree is -0.07MPa, and the mixture is stirred at 110rpm until the solid content of the mixture juice reaches 45% concentration; (iii) The concentration is cooled to 22℃ and filtered using a 120-mesh filter to obtain filtrate; (iv) The filtrate is transferred to a sealed storage tank and left to stand at 22℃ for 22min to obtain concentrated grain mixture juice.

[0117] The preparation process of the fermented slow-release granules is as follows: (I) Divide the core material into two equal parts by weight and prepare slow-release granules with different coating layers in batches: Take one part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete one round of coating. Take the other part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete one round of coating. Potato resistant starch powder was added to the granulator to complete three rounds of coating; fig pectin was sprayed onto the three coated core materials at a pressure of 0.115 MPa and rolled to form a continuous coating film. Finally, food-grade L-calcium lactate aqueous solution was sprayed at a single spray amount of 0.5% of the total mass of the core material. Then, the mixture was placed in a sealed container at room temperature of 22°C for 15 minutes and then transferred to a vacuum drying oven at 41°C until the moisture content of the material was 5% to obtain one layer of slow-release granules and three layers of slow-release granules; (II) The one layer of slow-release granules and three layers of slow-release granules were mixed evenly to obtain fermented slow-release granules.

[0118] After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0119] Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and then pack into a sealed fermentation tank.

[0120] A sealed fermentation tank was used to control the fermentation temperature at 21℃ for 13 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0121] The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 105 parts green vegetables, 9.45 parts salt, 4 parts water, 0.04 parts lactic acid bacteria, 11.5 parts pre-activated culture medium, and 0.92 parts fermentation slow-release granules.

[0122] The raw materials for preparing the pre-activated culture medium, by weight, include: 85 parts water, 10 parts food-grade glucose, and 18.5 parts malt extract.

[0123] The raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material (defatted and dephenolized cottonseed protein powder), 14 parts mixed grain juice (millet juice and corn juice in a mass ratio of 1:1), 6.5 parts fig pectin (fig pectin with a mass ratio of fig dry powder to water of 3.5%), 1.4 parts food-grade L-calcium lactate aqueous solution (mass concentration of 4.5%), and 85 parts potato resistant starch.

[0124] Comparative Example 6

[0125] A method for preparing low-salt lactic acid bacteria fermented sauerkraut includes the following steps:

[0126] The preparation process of the pre-activated culture medium is as follows: (i) Water is added to a mixing tank, then food-grade glucose is added, the temperature inside the tank is controlled at 22℃, the stirring speed is controlled at 200 rpm, and the mixture is stirred for 11 min to obtain a transparent sugar solution; (ii) Malt extract is added to the mixing tank and mixed with the transparent sugar solution, the stirring time is controlled at 7 min, the temperature inside the tank is controlled at 22℃, and the stirring speed is controlled at 265 rpm to obtain a composite culture solution; (iii) The temperature inside the tank is controlled at 22℃, the composite culture solution is stirred at 65 rpm, food-grade citric acid is added dropwise to adjust the pH to 6, and then the stirring is stopped to obtain a pre-pH culture solution; (iv) The pre-pH culture solution is allowed to stand for 16 min to obtain a pre-activated culture medium;

[0127] Lactic acid bacteria were added to a pre-activated culture medium and cultured at a constant temperature of 22℃ for 90 minutes to obtain activated lactic acid bacteria solution.

[0128] The preparation process of the grain mixture juice is as follows: (i) Millet juice and corn juice are put into a vacuum concentration tank and stirred until well mixed; (ii) The temperature inside the vacuum concentration tank is controlled at 55℃ and the vacuum degree is -0.07MPa, and the mixture is stirred at 110rpm until the solid content of the mixture juice reaches 45% concentration; (iii) The concentration is cooled to 22℃ and filtered using a 120-mesh filter to obtain filtrate; (iv) The filtrate is transferred to a sealed storage tank and left to stand at 22℃ for 22min to obtain concentrated grain mixture juice.

[0129] The preparation process of the fermented slow-release granules is as follows: (I) Divide the core material into two equal parts by weight and prepare slow-release granules with different coating layers in batches: Take one part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete one round of coating. Take the other part of the core material and place it in a pellet mill. Use a 0.135MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surfaces are evenly moistened and there is no dry material. Then add potato resistant starch dry powder into the pellet mill to complete one round of coating. Potato resistant starch powder was added to the granulator to complete two rounds of coating; fig pectin was sprayed onto the three coated core materials at a pressure of 0.115 MPa and rolled to form a continuous coating film. Finally, food-grade L-calcium lactate aqueous solution was sprayed at a single spray amount of 0.5% of the total mass of the core material. Then, the mixture was placed in a sealed container at room temperature of 22°C for 15 minutes and then transferred to a vacuum drying oven at 41°C until the moisture content of the material was 5% to obtain one layer of slow-release granules and two layers of slow-release granules; (II) The one layer of slow-release granules and the two layers of slow-release granules were mixed evenly to obtain fermented slow-release granules;

[0130] After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material.

[0131] Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and then pack into a sealed fermentation tank.

[0132] A sealed fermentation tank was used to control the fermentation temperature at 21℃ for 13 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

[0133] The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 105 parts green vegetables, 9.45 parts salt, 4 parts water, 0.04 parts lactic acid bacteria, 11.5 parts pre-activated culture medium, and 0.92 parts fermentation slow-release granules.

[0134] The raw materials for preparing the pre-activated culture medium, by weight, include: 85 parts water, 10 parts food-grade glucose, and 18.5 parts malt extract.

[0135] The raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material (defatted and dephenolized cottonseed protein powder), 14 parts mixed grain juice (millet juice and corn juice in a mass ratio of 1:1), 6.5 parts fig pectin (fig pectin with a mass ratio of fig dry powder to water of 3.5%), 1.4 parts food-grade L-calcium lactate aqueous solution (mass concentration of 4.5%), and 85 parts potato resistant starch.

[0136] Sauerkraut testing experiment

[0137] 1. The salt content of the low-salt lactic acid bacteria fermented sauerkraut prepared in Examples 1-3 and the salted sauerkraut prepared in Comparative Example 1 were tested according to the potentiometric titration method of GB 5009.44-2016 "National Food Safety Standard - Determination of Chloride in Food". The results are shown in Table 1.

[0138] 2. The total acid (calculated as lactic acid) of the low-salt lactic acid bacteria fermented sauerkraut prepared in Examples 1-3 and the salted sauerkraut prepared in Comparative Example 1 were determined according to the acid-base titration method of GB 12456-2021 "National Food Safety Standard - Determination of Total Acid in Food". The results are shown in Table 1.

[0139] 3. The low-salt lactic acid bacteria fermented sauerkraut prepared in Examples 1-3 and the salted sauerkraut prepared in Comparative Example 1 were tested according to GB 2714-2015 "National Food Safety Standard for Pickled Vegetables". The results are shown in Table 1.

[0140] Example 1 7.4% 1.1 It has a golden color, a distinct crispness, a pronounced sour and fragrant aroma, and a distinct sauerkraut flavor. Example 2 7.1% 1.02 It has a golden color, a distinct crispness, a pronounced sour and fragrant aroma, and a distinct sauerkraut flavor. Example 3 7.6% 0.98 It has a golden color, a distinct crispness, a sour and fragrant aroma, and a sauerkraut flavor. Comparative Example 1 11.2% 0.91 It is golden in color, has a distinct crispness, a slightly sour and savory aroma, a hint of pickled cabbage flavor, and a pronounced salty smell. Table 1

[0141] As can be seen from Table 1 above, the low-salt lactic acid bacteria fermented sauerkraut prepared according to Examples 1, 2, and 3 has a moderate total acidity and a lower salt content compared to the salted sauerkraut prepared in Comparative Example 1. In contrast, the traditional salted sauerkraut has a significantly lower acidity and a higher salt content. Furthermore, the traditional salted sauerkraut is also inferior to the low-salt lactic acid bacteria fermented sauerkraut in terms of sensory characteristics. Therefore, the preparation method of low-salt lactic acid bacteria fermented sauerkraut with lactic acid bacteria fermentation is superior. It reduces the amount of salt used, minimizes salt emissions during production, shortens the sauerkraut maturation period, and removes the salty flavor, thus enhancing the sauerkraut's flavor.

[0142] Lactic acid bacteria activity detection experiment

[0143] 1. The activity of the activated lactic acid bacteria solution prepared in Example 2 and the lactic acid bacteria used in Comparative Example 2 was tested according to GB 4789.35-2023 "National Food Safety Standard for Microbiological Examination of Food - Examination of Lactic Acid Bacteria". The results are shown in Table 2.

[0144] Example 1 <![CDATA[13.27×10 8 ]]> 0.63 Example 2 <![CDATA[16.21×10 8 ]]> 0.79 Example 3 <![CDATA[13.33×10 8 ]]> 0.67 Comparative Example 2 <![CDATA[10.12×10 8 ]]> 0.32 Table 2

[0145] As can be seen from Table 2 above, the activated lactic acid bacteria solutions prepared in Examples 1-3 have more live bacteria compared to the lactic acid bacteria directly used in Comparative Example 2. The activated lactic acid bacteria solution prepared in Example 2 is the best. The pre-activated culture medium is prepared by combining water, food-grade glucose and malt extract. The ratio of each raw material is scientifically adapted to the growth requirements of lactic acid bacteria. Pre-activating the lactic acid bacteria in this culture medium at a constant temperature before fermentation can quickly awaken dormant bacteria, significantly increase the number of live bacteria and the metabolic activity of the bacteria, accelerate the fermentation start-up rate of green vegetables, and greatly improve the overall fermentation and processing efficiency.

[0146] Lactic acid bacteria content detection experiment

[0147] 1. Based on GB 4789.35-2023 "National Food Safety Standard - Microbiological Examination of Food - Examination of Lactic Acid Bacteria"

[0148] The lactic acid bacteria content of the low-salt lactic acid bacteria fermented sauerkraut prepared in Examples 1-3 and Comparative Examples 3-6 was detected, and the results are shown in Table 3.

[0149] Example 2 <![CDATA[7.25×10 8 ]]> <![CDATA[9.61×10 8 ]]> <![CDATA[16.20×10 8 ]]> Comparative Example 3 <![CDATA[6.14×10 8 ]]> <![CDATA[8.33×10 8 ]]> <![CDATA[10.41×10 8 ]]> Comparative Example 4 <![CDATA[7.14×10 8 ]]> <![CDATA[8.48×10 8 ]]> <![CDATA[12.23×10 8 ]]> Comparative Example 5 <![CDATA[6.71×10 8 ]]> <![CDATA[8.44×10 8 ]]> <![CDATA[12.98×10 8 ]]> Comparative Example 6 <![CDATA[7.11×10 8 ]]> <![CDATA[8.97×10 8 ]]> <![CDATA[13.43×10 8 ]]> Table 3

[0150] As can be seen from Table 3 above, compared with Comparative Examples 3-6, Example 2 showed the best stability of the active number of lactic acid bacteria during the preparation of sauerkraut. Using defatted and dephenolized cottonseed protein powder as the nutrient core material, combined with grain mixed juice, fig pectin, and potato resistant starch, and cross-linked with food-grade L-calcium lactate aqueous solution to prepare gradient stratified fermentation slow-release granules, these granules can release carbon and nitrogen nutrients in stages and stably throughout the anaerobic fermentation process of sauerkraut, continuously supplying growth substrates for lactic acid bacteria, maintaining a high level of lactic acid bacteria activity throughout the process, ensuring a stable and sufficient fermentation process, and effectively improving the fermentation quality of sauerkraut.

[0151] The embodiments described above are merely examples of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A method for preparing sauerkraut fermented with low-salt lactic acid bacteria, characterized in that, Includes the following steps: Step S1: Add lactic acid bacteria to the pre-activated culture medium, maintain the ambient temperature at 20-25℃ for constant temperature culture, and activate for 60-120 minutes to obtain activated lactic acid bacteria solution; Step S2: After evenly mixing the green vegetables, salt, and fermented slow-release granules, divide the water into three equal parts and spray it evenly into the green vegetable mixture three times. After each spray, continue stirring for 3 minutes to obtain the mixed green vegetable material. Step S3: Add activated lactic acid bacteria solution to the mixed green vegetables, mix thoroughly, and pack into a sealed fermentation tank; Step S4: Seal the fermentation tank, control the fermentation temperature at 18-24℃, and ferment for 8-18 days to obtain low-salt lactic acid bacteria fermented sauerkraut.

2. The method for preparing low-salt lactic acid bacteria fermented sauerkraut according to claim 1, characterized in that, The raw materials for preparing the low-salt lactic acid bacteria fermented sauerkraut, by weight, include: 100-110 parts green vegetables, 9-9.9 parts salt, 2-6 parts water, 0.03-0.05 parts lactic acid bacteria, 8-15 parts pre-activated culture medium, 0.63-1.21 parts fermentation slow-release granules.

3. The method for preparing low-salt lactic acid bacteria fermented sauerkraut according to claim 2, characterized in that, The raw materials for preparing the pre-activated culture medium, by weight, include: 80-90 parts water, 8-12 parts food-grade glucose, and 15-22 parts malt extract.

4. The method for preparing low-salt lactic acid bacteria fermented sauerkraut according to claim 3, characterized in that, The preparation process of the pre-activated culture medium is as follows: (a) Add water to the mixing tank, then add food-grade glucose, control the temperature inside the tank to 20-25℃, control the stirring speed to 100-300rpm, and stir for 8-15 minutes to obtain a transparent sugar solution. (ii) Add malt extract stock solution to the mixing tank, mix and stir with transparent sugar solution, control the stirring time to 5-10 min, control the temperature inside the tank to 20-25℃, control the stirring speed to 200-330 rpm, and obtain composite culture solution; (iii) Control the temperature inside the tank to 20-25℃, stir the composite culture medium at a speed of 50-80 rpm, add food-grade citric acid to adjust the pH to 5.5-6.5, then stop stirring to obtain the pre-pH culture medium; (iv) Let the pre-pH culture medium stand for 8-24 minutes to obtain the pre-activated culture medium.

5. The method for preparing low-salt lactic acid bacteria fermented sauerkraut according to claim 1, characterized in that, The raw materials for preparing the fermented slow-release granules, by weight, include: 100 parts core material, 12-16 parts grain mixture juice, 3-10 parts fig pectin, 0.8-2.5 parts food-grade L-calcium lactate aqueous solution, and 40-130 parts potato resistant starch. Specifically, the core material is defatted and dephenolized cottonseed protein powder; The grain mixture juice, by weight, includes millet juice and corn juice in a 1:1 mass ratio.

6. The method for preparing low-salt lactic acid bacteria fermented sauerkraut according to claim 5, characterized in that, The preparation process of the grain mixture juice is as follows: (a) Add the millet juice and corn juice to the vacuum concentration tank and stir to mix well; (ii) Control the temperature inside the vacuum concentration tank to 50-60℃ and the vacuum degree to -0.06~-0.08MPa, and stir at a speed of 100-120rpm until the solid content of the mixture reaches 40%-50% of the concentrate. (iii) Cool the concentrate to 15-29℃ and filter it using a 120-mesh filter to obtain the filtrate; (iv) The filtrate is transferred into a sealed storage tank and left to stand at 20-24℃ for 15-30 minutes to obtain grain mixture juice.

7. The method for preparing low-salt lactic acid bacteria fermented sauerkraut according to claim 5, characterized in that, The preparation process of the fermented slow-release granules is as follows: (a) Divide the core material into three equal parts by weight and prepare controlled-release particles with different coating layers in batches: Take one portion of core material and place it in the pellet mill. Use a 0.12-0.15MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surface is evenly moistened and there is no dry material left. Then add potato resistant starch powder into the pellet mill to complete one round of coating. Take another portion of core material and place it in the pellet mill. Use a 0.12-0.15MPa atomizing nozzle to spray the grain mixture juice at a uniform speed until all the dry powder surface is evenly moistened and there is no dry material left. Then add potato resistant starch powder into the pellet mill to complete two rounds of coating. Take the last portion of core material and place it in the pellet mill. Use a 0.12-0.15MPa atomizing nozzle to spray the mixture juice. The grain mixture juice is sprayed at a uniform speed until all dry powder surfaces are evenly moistened and free of dry material. Then, potato resistant starch powder is added to the granulator to complete three rounds of coating. Fig pectin is sprayed onto the three coated core materials at a pressure of 0.10-0.13 MPa, and the mixture is rolled and bonded to form a continuous coating film. Finally, food-grade L-calcium lactate aqueous solution is sprayed at a single spray amount of 0.4%-0.6% of the total mass of the core material. Then, the mixture is sealed and left to stand at room temperature (20-24℃) for 15 minutes, and then transferred to a vacuum drying oven and dried at 40-42℃ until the moisture content of the material is 5% by mass, resulting in one-layer slow-release granules, two-layer slow-release granules, and three-layer slow-release granules. (ii) Mix one layer of slow-release granules, two layers of slow-release granules, and three layers of slow-release granules evenly to obtain fermentation slow-release granules.

8. The method for preparing low-salt lactic acid bacteria fermented sauerkraut according to claim 5, characterized in that, The fig pectin contains fig powder and water in a mass ratio of 3%-4%, and the food-grade L-calcium lactate aqueous solution has a mass concentration of 4%-5%.