Multi-strain soybean milk fermentation product and preparation method thereof

Abstract

The invention discloses a multi-strain soybean milk fermentation product and a preparation method thereof, and relates to the technical field of fermentation products. The strains in the mixed fermentation seed solution of the multi-strain soybean milk fermentation product comprise corynebacterium glutamicum, lactobacillus acidophilus, lactobacillus casei and streptococcus thermophilus, and the volume ratio of the soybean milk to the mixed fermentation seed solution is (62-85): 1. When the multi-strain soybean milk fermentation product is prepared, the synergistic effect of flora is good, the symbiotic efficiency is high, and the skin care effect of the fermentation product is excellent.

Description

Technical Field

[0001] The present invention relates to the field of fermented personal care products, and in particular to a multi-strain soymilk fermentation product and a preparation method thereof. Background Art

[0002] During the fermentation process of soy milk, proteins are broken down by microorganisms into more easily absorbed amino acids. These amino acids can not only provide nutrition for skin cells, but the monosaccharides and unsaturated fatty acids produced by fermentation have better cell membrane permeability and can more smoothly pass through the cell membrane into the cell, providing essential nutrition and energy for cell metabolism, promoting the normal functioning and vitality maintenance of cells, and also have moisturizing and repairing effects, which help to improve dry and rough skin conditions; and the organic acid polysaccharides, peptides, vitamins and other ingredients produced during the fermentation process have antioxidant, anti-inflammatory and anti-aging effects, which can reduce the damage of free radicals to the skin.

[0003] However, in the current multi-strain fermentation method for soy milk, the skin care effect of the fermented products generated is comparable to that of single-strain fermentation, the synergistic effect of the bacterial community is poor, the symbiotic efficiency is low, and the skin care effect of the fermented products is not ideal. Summary of the invention

[0004] The present invention is made in view of the above-mentioned problems and provides a multi-strain soymilk fermentation product and a preparation method thereof.

[0005] The first aspect of the present invention provides a multi-strain soy milk fermentation product, wherein the strains in the mixed fermentation seed liquid of the multi-strain soy milk fermentation product include Corynebacterium glutamicum, Lactobacillus acidophilus, Lactobacillus casei and Streptococcus thermophilus, and the volume ratio of the soy milk to the mixed fermentation seed liquid is (62-85):1.

[0006] In some embodiments of the present invention, the average number of strain cells in the mixed fermentation seed solution is (1.5-2.5)×10 7 Bacterial count / mL.

[0007] In some embodiments of the present invention, in the mixed fermentation seed liquid, the volume ratio of Corynebacterium glutamicum seed liquid, Lactobacillus acidophilus seed liquid, Lactobacillus casei seed liquid and Streptococcus thermophilus seed liquid is 1:1:1:1.

[0008] A second aspect of the present invention provides a method for preparing a multi-strain soymilk fermentation product, comprising the following steps:

[0009] S1, sterilize the soy milk and pour it into a stainless steel fermentation tank;

[0010] S2, inverting 4 inoculation bottles of different strain types on the inoculation tube and tightening them, the seed liquid in the inoculation bottle flows into the retention bottle along the strain transmission tube by gravity and mixes to obtain a mixed seed liquid, and the mixed seed liquid is allowed to flow into the fermentation tank to complete the inoculation;

[0011] S3, setting fermentation parameters, inactivating after fermentation is completed, and obtaining multi-strain soy milk fermentation products.

[0012] In some embodiments of the present invention, the sterilization includes using atmospheric pressure cold plasma to treat deionized water to generate activated water, and the activated water is mixed with soy milk for cyclic treatment.

[0013] In some embodiments of the present invention, the volume ratio of the activated water to the soy milk is 1:(7-9).

[0014] In some embodiments of the present invention, the temperature of the cyclic treatment is less than 40°C.

[0015] In some embodiments of the present invention, the fermentation parameters include a fermentation temperature of 25 to 32° C. and a fermentation time of 3 to 7 days.

[0016] In some embodiments of the present invention, the stainless steel fermenter includes a spiral stirring propeller with a surface contact angle of >150°, and the fermentation parameters include setting the rotation speed of the spiral stirring propeller to 150 r / min to 280 r / min.

[0017] In some embodiments of the present invention, the inactivation destroys the cell membrane potential by a 10T pulsed magnetic field, thereby inhibiting the protease activity to ≤5%.

[0018] The beneficial effects that can be achieved by the present invention are:

[0019] The present invention provides a multi-strain soy milk fermentation product, wherein Corynebacterium glutamicum can decompose protein to produce multiple amino acids, provide nutrition for thermophilic streptococcus, promote its rapid growth and acid production, and accelerate the fermentation process. At the same time, the rapid metabolism of thermophilic streptococcus can change environmental conditions, which is conducive to the growth and metabolism of other strains, and jointly promotes fermentation. Multiple strains interact to form a stable flora structure, and each strain restricts and balances each other, improves the stability of the fermentation system, and makes the fermentation process more stable. Finally, multiple strains synergistically decompose macromolecules into small molecule peptides, amino acids, bacteriocins, lactic acid, trace minerals, etc., which are more easily absorbed by the skin, improve the bioavailability of nutrients in cosmetics, and enable the skin to more fully absorb and utilize the effective ingredients therein, so as to better play the skin care effect of cosmetics. DETAILED DESCRIPTION

[0020] The following description is provided for those skilled in the art to fully understand the present invention, and is not intended to limit the subject matter described in the claims.

[0021] The "range" disclosed in the present invention is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range. For example, if a range of 60 to 120 and 80 to 110 is listed for a particular parameter, it is understood that a range of 60 to 110 and 80 to 120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following ranges can all be expected: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4 and 2 to 5. In the present invention, unless otherwise specified, the numerical range "a to b" represents an abbreviation of any real number combination between a and b, wherein a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0022] If not otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form a new technical solution.

[0023] Unless otherwise specified, all technical features and optional technical features of the present invention can be combined with each other to form a new technical solution.

[0024] If not otherwise specified, all steps of the present invention may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0025] During the fermentation process of soy milk, proteins are broken down by microorganisms into more easily absorbed amino acids. These amino acids can not only provide nutrition for skin cells, but the monosaccharides and unsaturated fatty acids produced by fermentation have better cell membrane permeability and can more smoothly pass through the cell membrane into the cell, providing essential nutrition and energy for cell metabolism, promoting the normal functioning and vitality maintenance of cells, and also have moisturizing and repairing effects, which help to improve dry and rough skin conditions; and the organic acid polysaccharides, peptides, vitamins and other ingredients produced during the fermentation process have antioxidant, anti-inflammatory and anti-aging effects, which can reduce the damage of free radicals to the skin.

[0026] However, in the current multi-strain fermentation method for soy milk, the skin care effect of the fermented products generated is comparable to that of single-strain fermentation, the synergistic effect of the bacterial flora is poor, the symbiotic efficiency is low, and the skin care effect is not ideal.

[0027] In view of this, the present invention proposes a multi-strain soy milk fermentation product, wherein the strains in the mixed fermentation seed liquid of the multi-strain soy milk fermentation product include Corynebacterium glutamicum, Lactobacillus acidophilus, Lactobacillus casei and Streptococcus thermophilus, and the volume ratio of the soy milk to the mixed fermentation seed liquid is (62-85):1.

[0028] Corynebacterium glutamicum efficiently metabolizes glutamine in soy protein to generate free glutamate, and stabilizes the pH of the fermentation system at 5.8-6.2 through deamination, providing a weakly acidic environment for the symbiosis of Lactobacillus acidophilus and Lactobacillus casei.

[0029] Lactobacillus acidophilus and Lactobacillus casei work together to secrete β-glucosidase, which converts soy isoflavone glycosides into active aglycones, decomposes phytic acid, and releases mineral components to participate in anti-aging.

[0030] Streptococcus thermophilus secretes heat-resistant proteases that rapidly hydrolyze soybean protein into peptides in the early stages of fermentation and enhance catalytic efficiency in a multi-strain system.

[0031] The volume ratio of this solution is set to optimize the carbon-nitrogen ratio, match the ratio of total sugar to protein in soy milk with the needs of the bacterial community, avoid excessive proliferation of a single strain, and promote aerobic metabolism of Corynebacterium glutamicum at a low inoculation amount and initial dissolved oxygen; as fermentation proceeds, lactic acid bacteria dominate anaerobic fermentation, forming a dynamic metabolic relay. In some embodiments, soy milk specifically refers to soy milk made from black beans.

[0032] In the multi-strain soy milk fermentation product of this scheme, Corynebacterium glutamicum can decompose protein to produce a variety of amino acids, provide nutrition for Streptococcus thermophilus, promote its rapid growth and acid production, and accelerate the fermentation process. At the same time, the rapid metabolism of Streptococcus thermophilus can change environmental conditions, which is conducive to the growth and metabolism of other strains, and jointly promotes the fermentation process. Multiple strains interact with each other to form a stable flora structure, and each strain restricts and balances each other, improves the stability of the fermentation system, and makes the fermentation process more stable. Ultimately, the synergistic effect of multiple strains can decompose macromolecules into small molecule peptides, amino acids, bacteriocins, lactic acid, trace minerals and other ingredients that are more easily absorbed by the skin, improve the bioavailability of nutrients in cosmetics, and enable the skin to more fully absorb and utilize the effective ingredients therein, thereby better exerting the skin care effect of cosmetics.

[0033] In some embodiments, the average number of strain cells in the mixed fermentation seed liquid is (1.5-2.5)×10 7 By controlling the cell count of the strain, the fermentation process can be controlled more accurately, ensuring the stability and consistency of the fermentation conditions, thereby improving the quality and efficacy of the fermentation product.

[0034] In some embodiments, in the mixed fermentation seed solution, the volume ratio of Corynebacterium glutamicum seed solution, Lactobacillus acidophilus seed solution, Lactobacillus casei seed solution and Streptococcus thermophilus seed solution is 1:1:1:1. This ratio avoids excessive action of a single strain, and the efficiency of synergistic fermentation is higher.

[0035] The second aspect of the present invention provides a method for preparing the multi-strain soymilk fermentation product, comprising the following steps:

[0036] S1, sterilize the soy milk and pour it into a stainless steel fermentation tank;

[0037] S2, inverting 4 inoculation bottles of different strain types on the inoculation tube and tightening them, the seed liquid in the inoculation bottle flows into the retention bottle along the strain transmission tube by gravity and mixes to obtain a mixed seed liquid, and the mixed seed liquid is allowed to flow into the fermentation tank to complete the inoculation;

[0038] S3, setting fermentation parameters, inactivating after fermentation is completed, and obtaining multi-strain soy milk fermentation products.

[0039] By sterilizing and killing the foreign bacteria in soy milk, we can ensure that only the target strains participate in the fermentation process, thereby avoiding the contamination of foreign bacteria that affects the quality and safety of the fermentation products.

[0040] It can be understood that the four inoculation bottles of different strain types are containers for the above four strains (Corynebacterium glutamicum seed liquid, Lactobacillus acidophilus seed liquid, Lactobacillus casei seed liquid and Streptococcus thermophilus seed liquid).

[0041] The mixed seed liquid flows into the fermentation tank through the strain transmission tube to complete the inoculation. This inoculation method can ensure that the seed liquid is evenly distributed in the soy milk in the fermentation tank, promoting uniform fermentation. In some embodiments, the inoculation of step S2 also uses a micro flow pump and a sensor to control the flow rate of each strain flowing into the retention bottle in real time to ensure an accurate volume ratio.

[0042] After fermentation, it is inactivated to ensure that it will not cause skin infection or other adverse reactions during use.

[0043] In some embodiments, sterilization includes treating deionized water with atmospheric pressure cold plasma to generate activated water, and the activated water is mixed with soy milk for cyclic treatment. CAP can produce a variety of active substances, such as hydroxyl radicals (·OH), hydrogen peroxide (H 2 O 2 ), superoxide (O 2 - ·), singlet oxygen ( 1 O 2 ) and ozone (O 3 ), these substances have a strong bactericidal effect and can effectively kill bacteria in soy milk, ensuring that only the target strains participate in the fermentation process, avoiding the contamination of bacteria affecting the quality and safety of the fermentation products. CAP treatment can be completed in a short time. Compared with traditional heat sterilization methods, it greatly shortens the sterilization time and improves production efficiency, achieving a spore inactivation rate of >99.99%, a protein retention rate of >95%, and an isoflavone loss rate of <5%.

[0044] In some embodiments, conventional high temperature and high pressure sterilization, pasteurization, UHT ultra-high temperature instantaneous sterilization, membrane filtration sterilization, irradiation sterilization, high hydrostatic pressure sterilization and other methods can also replace the sterilization step of this solution, but it is difficult to achieve the above-mentioned effect.

[0045] In some embodiments, the volume ratio of the activated water to the soy milk is 1:(7-9). Preferably, the volume ratio is 1:9.

[0046] In some embodiments, the temperature of the circulation treatment is less than 40° C. The low treatment temperature can retain the inherent nutrients of the soy milk to the maximum extent and avoid damaging the fermentation matrix.

[0047] In some embodiments, the fermentation parameters include a fermentation temperature of 25-32° C. and a fermentation time of 3-7 days. Preferably, the fermentation temperature is 28° C. and the fermentation time is 5 days.

[0048] In some embodiments, the stainless steel fermenter includes a propeller with a surface contact angle of >150°, and the fermentation parameters include setting the rotation speed of the propeller to 150 r / min to 280 r / min. During the stirring process, the droplets form a "lotus effect" on the super-hydrophobic surface, reducing the adsorption of macromolecules such as proteins and polysaccharides.

[0049] In some embodiments, the inactivation destroys the cell membrane potential by a 10T pulsed magnetic field, inhibiting the protease activity to ≤5%, ensuring that the remaining strains fermented during use will not cause skin infection or other adverse reactions.

[0050] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the following specific embodiments are only used to explain the present invention, and are not used to limit the present invention.

[0051] Example 1

[0052] S1. Using atmospheric pressure cold plasma to treat deionized water to generate activated water, mixing the activated water with soybean milk, with a mixing volume ratio of activated water: soybean milk = 1:9, performing a mixing cycle treatment at 30° C. to sterilize the soybean milk, and then pouring it into a stainless steel fermentation tank;

[0053] S2. Invert four different inoculation bottles containing Corynebacterium glutamicum seed solution, Lactobacillus acidophilus seed solution, Lactobacillus casei seed solution and Streptococcus thermophilus seed solution in a volume ratio of 1:1:1:1 on the inoculation tube and tighten them. The seed solution in the inoculation bottle flows into the retention bottle along the strain transmission tube by gravity and is mixed to obtain a mixed seed solution. The average number of strain cells in the mixed seed solution is 2×10 7 The number of bacteria / mL, the mixed seed liquid was allowed to flow into the fermentation tank, the volume ratio of soy milk and mixed fermentation seed liquid was 70:1, and the inoculation was completed;

[0054] S3. The rotation speed of the spiral stirring paddle (surface contact angle>150°) in the stainless steel fermentation tank is set to 220 r / min, and the fermentation is carried out at 28° C. for 5 days. After the fermentation is completed, the cell membrane potential is destroyed by a 10T pulse magnetic field, and the protease activity is inhibited to ≤5%, thereby obtaining a multi-strain soymilk fermentation product.

[0055] Example 2

[0056] The average number of strain cells in the mixed fermentation seed solution was 1.5×10 7 The number of bacteria / mL, the volume ratio of soy milk to the mixed fermentation seed liquid is 78:1, and the rest is referred to Example 1.

[0057] Comparative Example 1

[0058] Only the Corynebacterium glutamicum seed solution was used for fermentation, so that the volume ratio of soy milk to the Corynebacterium glutamicum seed solution was 70:1. The rest was referred to Example 1.

[0059] Comparative Example 2

[0060] Only Lactobacillus acidophilus seed liquid was used for fermentation, so that the volume ratio of soy milk to Lactobacillus acidophilus seed liquid was 70:1. The rest was referred to Example 1.

[0061] Comparative Example 3

[0062] Only Lactobacillus casei seed liquid was used for fermentation, so that the volume ratio of soy milk to Lactobacillus casei seed liquid was 70:1. The rest was referred to Example 1.

[0063] Comparative Example 4

[0064] Only the thermophilic Streptococcus seed liquid was used for fermentation, so that the volume ratio of soy milk to the thermophilic Streptococcus seed liquid was 70:1. The rest was referred to Example 1.

[0065] Performance Test:

[0066] The total amount of free amino acids (HPLC), isoflavone aglycone conversion rate (HPLC), and phytic acid degradation rate of the multi-strain soymilk fermentation products obtained in the examples and comparative examples were measured, and the results were recorded in Table 1.

[0067] 1. Total free amino acids

[0068] After derivatization, the amino acids were separated and quantified using a chromatographic column.

[0069] 2. Isoflavone aglycone conversion rate

[0070] Isoflavone glycosides (such as daidzein and genistein) are hydrolyzed into aglycones (such as daidzein and genistein) by β-glucosidase, and the conversion rate is calculated by the chromatographic peak area.

[0071] 3. Phytic acid degradation rate

[0072] Phytic acid and FeCl3 form a complex under acidic conditions, and the unreacted Fe in the supernatant is measured after centrifugation. 3 + (color development with sulfosalicylic acid), and indirectly calculate the phytic acid content.

[0073] Furthermore, the multi-strain soy milk fermentation products of Examples 1-2 and Comparative Examples 1-4 were mixed with conventional doses of water, butylene glycol and 1,2-pentanediol to prepare skin care water. The addition amount of the multi-strain soy milk fermentation products was 1%. A total of 30 test volunteers were divided into 6 groups to use the skin care water once in the morning and once in the evening. After 2 weeks, the allergy rate (%), soothing effect (reduce redness) (0-10 points), moisturizing effect (0-10 points) and absorption feeling (0-10 points) were tested, and the results were recorded in Table 2.

[0074] Table 1: Characterization test results of Examples 1 to 2 and Comparative Examples 1 to 4

[0075]

[0076] Table 2: Trial test results of Examples 1 to 2 and Comparative Examples 1 to 4

[0077]

[0078] It can be seen from Table 1 and Table 2 that the Corynebacterium glutamicum in the multi-strain soy milk fermentation product of this scheme can decompose protein to produce various amino acids, provide nutrition for thermophilic streptococci, promote its rapid growth and acid production, and accelerate the fermentation process. At the same time, the rapid metabolism of thermophilic streptococci can change environmental conditions, which is conducive to the growth and metabolism of other strains, and jointly promotes fermentation. Multiple strains interact to form a stable flora structure, and each strain restricts and balances each other, improves the stability of the fermentation system, and makes the fermentation process more stable. Finally, the synergistic effect of multiple strains can decompose macromolecules into small molecule peptides, amino acids, bacteriocins, lactic acid, trace minerals, etc., which are more easily absorbed by the skin, improve the bioavailability of nutrients in cosmetics, and enable the skin to more fully absorb and utilize the effective ingredients therein, so as to better play the skin care effect of cosmetics.

[0079] It should be noted that the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments are only examples, and the embodiments having the same structure as the technical idea and exerting the same effect within the scope of the technical solution of the present invention are all included in the technical scope of the present invention. In addition, without departing from the scope of the main purpose of the present invention, various modifications that can be thought of by those skilled in the art to the embodiments and other methods of combining some of the constituent elements in the embodiments are also included in the scope of the present invention.

Claims

1. A multi-strain soymilk fermentation product, characterized in that: The strains in the mixed fermentation seed liquid of the multi-strain soy milk fermentation product include Corynebacterium glutamicum, Lactobacillus acidophilus, Lactobacillus casei and Streptococcus thermophilus. The volume ratio of the soy milk to the mixed fermentation seed liquid is (62-85):

1.

2. The multi-strain soymilk fermentation product according to claim 1, characterized in that: The average number of strain cells in the mixed fermentation seed liquid is (1.5-2.5)×10 7 Bacterial count / mL.

3. The multi-strain soymilk fermentation product according to claim 1 or 2, characterized in that: In the mixed fermentation seed liquid, the volume ratio of the Corynebacterium glutamicum seed liquid, the Lactobacillus acidophilus seed liquid, the Lactobacillus casei seed liquid and the Streptococcus thermophilus seed liquid is 1:1:1:

1.

4. A method for preparing a multi-strain soymilk fermentation product according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1, sterilize the soy milk and pour it into a stainless steel fermentation tank; S2, inverting 4 inoculation bottles of different strain types on the inoculation tube and tightening them, the seed liquid in the inoculation bottle flows into the retention bottle along the strain transmission tube by gravity and mixes to obtain a mixed seed liquid, and the mixed seed liquid is allowed to flow into the fermentation tank to complete the inoculation; S3, setting fermentation parameters, inactivating after fermentation is completed, and obtaining multi-strain soy milk fermentation products.

5. The method for preparing a multi-strain soymilk fermentation product according to claim 4, characterized in that: The sterilization comprises treating deionized water with atmospheric pressure cold plasma to generate activated water, and the activated water is mixed with soybean milk for cyclic treatment.

6. The method for preparing a multi-strain soymilk fermentation product according to claim 5, characterized in that: The volume ratio of the activated water to the soy milk is 1:(7-9).

7. The method for preparing a multi-strain soymilk fermentation product according to claim 5, characterized in that: The temperature of the cycle treatment is less than 40°C.

8. The method for preparing a multi-strain soymilk fermentation product according to claim 4, characterized in that: The fermentation parameters include a fermentation temperature of 25 to 32° C. and a fermentation time of 3 to 7 days.

9. The method for preparing a multi-strain soymilk fermentation product according to claim 4, characterized in that: The stainless steel fermenter includes a spiral stirring propeller with a surface contact angle of more than 150°, and the fermentation parameters include setting the rotation speed of the spiral stirring propeller to 150 r / min to 280 r / min.

10. The method for preparing a multi-strain soymilk fermentation product according to claim 4, characterized in that: The inactivation destroys the cell membrane potential by a 10T pulse magnetic field, thereby inhibiting the protease activity to ≤5%.

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