Fermented milk rich in lactobacillus plantarum and preparation method thereof

Abstract

The invention discloses fermented milk rich in lactobacillus plantarum and a preparation method thereof, relates to the technical field of fermented milk, and aims to solve the technical problem that the taste of the produced fermented milk cannot achieve an expected effect due to the fact that an existing continuous stirring mode is not beneficial to the fermentation process of raw materials. Comprising the following components in percentage by weight: 85%-99% of high-quality fresh milk, 0.05%-0.5% of a growth promoter, 0.001%-0.05% of a composition of cytosine nucleotide and uracil nucleotide, 0.5%-10% of oligosaccharide, 0.1%-0.8% of carrageenan, 0.01%-0.05% of a natural vanilla extract and the balance of an efficient leavening agent. The efficient leavening agent comprises zymophyte, vitamins, mineral substances and precursor substances, and the inoculum size of the zymophyte is 1.0 * 10 < 6 >-5.0 * 10 < 7 > CFU / mL; the zymophyte is any one of high-activity lactobacillus plantarum, streptococcus thermophilus or lactobacillus casei; wherein the high-activity lactobacillus plantarum is lactobacillus fermentum ELF041, and the preservation number of the lactobacillus fermentum ELF041 is CCTCC (China Center For Type Culture Collection) NO: M20221240. The method has the advantages that the fermentation effect of the raw materials is promoted, and the taste of the fermented milk is improved.

Description

Technical Field

[0001] The invention relates to the technical field of fermented milk, and more specifically to a fermented milk rich in Lactobacillus plantarum and a preparation method thereof. Background Art

[0002] Fermented milk (yogurt) is an acidic curd-like product made by fermenting milk and dairy products under the action of characteristic bacteria. The characteristic bacteria of this type of product must exist in large quantities, survive and be active during the shelf life. Therefore, fermented milk refers to a curd-like product made by adding lactic acid bacteria (Lactobacillus bulgaricus and Streptococcus thermophilus) to milk and fermenting it with lactic acid. The finished product must contain a large number of corresponding active microorganisms.

[0003] At present, for fermented milk rich in Lactobacillus plantarum, the raw materials usually need to be stirred during the production process. The traditional stirring method is continuous stirring. During the fermentation process of the raw materials, the continuous stirring method is not conducive to the fermentation process of the raw materials, which results in the taste of the produced fermented milk failing to achieve the expected effect. In view of this, we propose a fermented milk rich in Lactobacillus plantarum and a method for manufacturing the same. Summary of the invention

[0004] One of the purposes of the present invention is to provide a fermented milk rich in Lactobacillus plantarum to solve the technical problem that the existing continuous stirring method is not conducive to the fermentation process of the raw materials, resulting in the taste of the produced fermented milk failing to achieve the expected effect.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a fermented milk rich in Lactobacillus plantarum, comprising the following components in weight percentage: 85-99% high-quality fresh milk, 0.05-0.5% growth promoter, 0.001-0.05% cytosine nucleotide and uracil nucleotide composition, 0.5-10% oligosaccharide, 0.1-0.8% carrageenan, 0.01-0.05% natural vanilla extract, and the rest are high-efficiency fermentation agents;

[0006] The high-efficiency fermentation agent includes fermentation bacteria, vitamins, minerals and precursor substances, wherein the inoculation amount of the fermentation bacteria is 1.0×10 6 Up to 5.0×10 7 CFU / mL;

[0007] The fermentation bacteria is any one of highly active Lactobacillus plantarum, Streptococcus thermophilus or Lactobacillus casei;

[0008] Wherein, the highly active plant lactobacillus is fermented lactobacillus ELF041, and the preservation number of fermented lactobacillus ELF041 is CCTCCNO: M20221240.

[0009] Preferably, the growth promoter is a mixture of valine and leucine.

[0010] The second object of the present invention is to provide a method for producing the above-mentioned fermented milk rich in Lactobacillus plantarum, comprising the following steps:

[0011] S1, raw material selection and pretreatment;

[0012] Select fresh, pollution-free, high-quality fresh milk with a fat content of 3.0-4.0%, and pre-treat it through a double filter to remove impurities and microorganisms, wherein the pore size of the double filter is ≤0.5μm;

[0013] S2, batching and mixing;

[0014] At a temperature of 45-55°C, the pretreated milk and all the above components are mixed uniformly in a high-speed stirrer according to a predetermined ratio, and the stirring speed is controlled at 1000-1500 rpm for 5-10 minutes;

[0015] S3, homogenization and sterilization;

[0016] Two-stage homogenization technology is used, with the first stage homogenization pressure of 150-200 bar and the second stage homogenization pressure of 5-10 bar, followed by pasteurization at 85-90℃ for 30 minutes, or high temperature short-time sterilization at 130-135℃ for 4-8 seconds;

[0017] S4, inoculation and fermentation;

[0018] On a sterile operating table, a high-efficiency starter is inoculated into cow milk cooled to 40-42° C., and sealed fermentation is performed immediately after inoculation. During the fermentation process, the temperature of the fermentation chamber is controlled to be 41±0.5° C., the fermentation time is 6-10 hours, and intermittent stirring is adopted, stirring once every 30 minutes, each stirring lasts for 2 minutes, the stirring speed is controlled at 50-100 rpm, and a trace amount of oxygen is introduced to promote the growth of Lactobacillus plantarum, wherein the oxygen concentration is controlled at 0.5-1.5%;

[0019] S5, post-processing and packaging;

[0020] After fermentation, the fermented milk is immediately cooled to below 4°C and gently stirred to prevent precipitation. It is then aseptically filled into pre-sterilized PET bottles or glass bottles, sealed and stored in a refrigerated environment at 2-6°C.

[0021] Furthermore, step S1 also includes standardizing the milk, adjusting the fat content to 3.2-3.5%, and removing whey protein and other non-fat solid impurities in the milk by centrifugation to improve the stability and taste of the fermented milk.

[0022] Furthermore, in step S2, phosphate buffer is added during the mixing process to maintain pH stability during the fermentation process and further promote the growth of Lactobacillus plantarum.

[0023] Furthermore, in step S3, a preheating treatment is performed before homogenization to raise the temperature of the milk to 55-60° C. to soften the fat globule membrane and improve the homogenization effect.

[0024] Furthermore, in step S4, the fermentation container is disinfected before inoculation, and a sterile air filtration system is used to ensure that there is no exogenous microbial contamination during the inoculation process. In addition, the pH value and redox potential of the fermentation liquid are monitored to adjust the fermentation conditions in a timely manner and optimize the growth environment of Lactobacillus plantarum.

[0025] Furthermore, in step S5, the post-treatment process also includes homogenization treatment to further refine the texture of the fermented milk and improve its taste and stability.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The invention adopts intermittent stirring, stirring once every 30 minutes, each stirring lasting for 2 minutes, and controlling the stirring speed at 50-100 rpm, which is conducive to staged stagnation in the fermentation process of the raw material, providing a static fermentation process for the raw material for a certain period of time, thereby facilitating the fermentation effect of the raw material and improving the taste of the fermented milk produced, and optionally introducing a trace amount of oxygen to promote the growth of plant lactobacillus, thereby increasing the density of textile lactobacillus, thereby further promoting the fermentation process and improving the fermentation effect of the raw material.

[0028] Biological Deposit Description

[0029] Biological material: ELF041, classification name: Lactiplantibacillus fermertum, deposited in the China Center for Type Culture Collection on August 4, 2022, the address of the collection center is: Wuhan University, No. 299, Bayi Road, Wuchang District, Wuhan City, Hubei Province; the collection number is CCTCCNO: M20221240.

[0030] The ELF041 described in the present invention is the strain with the above-mentioned deposit number of CCTCCNO: M20221240. DETAILED DESCRIPTION

[0031] In order to facilitate those skilled in the art to understand the technical solution of the present invention, the technical solution of the present invention is further explained.

[0032] Embodiment 1

[0033] The present embodiment provides a fermented milk rich in Lactobacillus plantarum, comprising the following components in weight percentage: 85-99% high-quality fresh milk, 0.05-0.5% growth promoter, 0.001-0.05% cytosine nucleotide and uracil nucleotide composition, 0.5-10% oligosaccharide, 0.1-0.8% carrageenan, 0.01-0.05% natural vanilla extract, and the rest are high-efficiency fermentation agents;

[0034] The high-efficiency fermentation agent includes fermentation bacteria, vitamins, minerals and precursor substances, wherein the inoculation amount of the fermentation bacteria is 1.0×10 6 Up to 5.0×10 7 CFU / mL;

[0035] The fermentation bacteria is any one of highly active Lactobacillus plantarum, Streptococcus thermophilus or Lactobacillus casei;

[0036] Among them, the highly active plant lactobacillus is fermented lactobacillus ELF041, and the preservation number of fermented lactobacillus ELF041 is CCTCCNO: M20221240; fermented lactobacillus, as a potential probiotic, is widely distributed in the gastrointestinal tract and is a normal flora of the intestine, oral cavity and vagina; fermented lactobacillus has the functions of acid and bile resistance, cholesterol degradation, antioxidant, antibacterial and the like, and it can also regulate the balance of the host microbial flora, can reach the intestine through oral administration, is well adsorbed on the epithelial cells of the small intestine, and produces surfactant components to prevent harmful bacteria from adhering to the intestine, thereby improving the system environment in the host body and promoting the health of the host.

[0037] The growth promoter is a mixture of valine and leucine.

[0038] Embodiment 2

[0039] This embodiment provides a method for producing fermented milk rich in Lactobacillus plantarum in Embodiment 1, comprising the following steps:

[0040] S1, raw material selection and pretreatment;

[0041] Select fresh, pollution-free, high-quality fresh milk with a fat content of 3.0%, and pre-treat it through a double filter to remove impurities and microorganisms, wherein the pore size of the double filter is ≤0.5μm; standardize the milk to adjust the fat content to 3.2%, and remove whey protein and other non-fat solid impurities in the milk through centrifugation to improve the stability and taste of the fermented milk;

[0042] S2, batching and mixing;

[0043] The pretreated milk and all the above components were mixed uniformly in a high-speed stirrer at a temperature of 45°C according to a predetermined ratio, and the stirring speed was controlled at 1000 rpm for 5 minutes; wherein, a phosphate buffer was also added during the mixing process to maintain pH stability during the fermentation process and further promote the growth of Lactobacillus plantarum;

[0044] S3, homogenization and sterilization;

[0045] First, the milk is preheated to 55°C to soften the fat globule membrane and improve the homogenization effect. Then, a two-stage homogenization technology is used, with a first-stage homogenization pressure of 150 bar and a second-stage homogenization pressure of 5 bar. Then, the milk is pasteurized at 85°C for 30 minutes, or at 130°C for 4 seconds.

[0046] S4, inoculation and fermentation;

[0047] The fermentation container is disinfected before inoculation, and a sterile air filtration system is used to ensure that there is no exogenous microbial contamination during the inoculation process. In addition, the pH value and redox potential of the fermentation liquid are monitored to adjust the fermentation conditions in a timely manner and optimize the growth environment of Lactobacillus plantarum. Then, on a sterile operating table, a high-efficiency starter is introduced into the cow's milk cooled to 40°C, and sealed fermentation is performed immediately after inoculation. During the fermentation process, the temperature of the fermentation chamber is controlled to be 41°C, the fermentation time is 6 hours, and intermittent stirring is adopted, stirring once every 30 minutes, each stirring lasts for 2 minutes, the stirring speed is controlled at 50rpm, and a trace amount of oxygen is introduced to promote the growth of Lactobacillus plantarum, wherein the oxygen concentration is controlled at 0.5%;

[0048] S5, post-processing and packaging;

[0049] After fermentation, the fermented milk is immediately cooled to below 4°C and gently stirred to prevent precipitation. It is then aseptically filled into pre-sterilized PET bottles or glass bottles, sealed and stored in a refrigerated environment at 4°C.

[0050] Embodiment 3

[0051] This embodiment provides a method for producing fermented milk rich in Lactobacillus plantarum in Embodiment 1, comprising the following steps:

[0052] S1, raw material selection and pretreatment;

[0053] Select fresh, pollution-free high-quality fresh milk with a fat content of 4.0%, and pre-treat it through a double filter to remove impurities and microorganisms, wherein the pore size of the double filter is ≤0.5μm; standardize the milk to adjust the fat content to 3.5%, and remove whey protein and other non-fat solid impurities in the milk through centrifugation to improve the stability and taste of the fermented milk;

[0054] S2, batching and mixing;

[0055] The pretreated milk and all the above components were mixed uniformly in a high-speed stirrer at a temperature of 55°C according to a predetermined ratio, and the stirring speed was controlled at 1500 rpm for 10 minutes. A phosphate buffer was also added during the mixing process to maintain pH stability during the fermentation process and further promote the growth of Lactobacillus plantarum.

[0056] S3, homogenization and sterilization;

[0057] First, the milk is preheated to 60°C to soften the fat globule membrane and improve the homogenization effect. Then, a two-stage homogenization technology is used, with a first-stage homogenization pressure of 200 bar and a second-stage homogenization pressure of 10 bar. Then, the milk is pasteurized at 90°C for 30 minutes, or at 135°C for 4 seconds.

[0058] S4, inoculation and fermentation;

[0059] The fermentation container is disinfected before inoculation, and a sterile air filtration system is used to ensure that there is no exogenous microbial contamination during the inoculation process. In addition, the pH value and redox potential of the fermentation liquid are monitored to adjust the fermentation conditions in a timely manner and optimize the growth environment of Lactobacillus plantarum. Then, on a sterile operating table, a high-efficiency starter is introduced into the milk cooled to 42° C., and sealed fermentation is performed immediately after inoculation. During the fermentation process, the temperature of the fermentation chamber is controlled to be 41° C., the fermentation time is 10 hours, and intermittent stirring is adopted, stirring once every 30 minutes, each stirring lasts for 2 minutes, the stirring speed is controlled at 100 rpm, and a trace amount of oxygen is introduced to promote the growth of Lactobacillus plantarum, wherein the oxygen concentration is controlled at 1.5%;

[0060] S5, post-processing and packaging;

[0061] After fermentation, the fermented milk is immediately cooled to below 4°C and gently stirred to prevent precipitation. It is then aseptically filled into pre-sterilized PET bottles or glass bottles, sealed and stored in a refrigerated environment at 4°C.

[0062] The invention adopts intermittent stirring, stirring once every 30 minutes, each stirring lasting for 2 minutes, and controlling the stirring speed at 50-100 rpm, which is conducive to staged stagnation in the fermentation process of the raw material, providing a static fermentation process for the raw material for a certain period of time, thereby facilitating the fermentation effect of the raw material and improving the taste of the fermented milk produced, and optionally introducing a trace amount of oxygen to promote the growth of plant lactobacillus, thereby increasing the density of textile lactobacillus, thereby further promoting the fermentation process and improving the fermentation effect of the raw material.

[0063] The embodiments of the present invention disclose preferred embodiments, but are not limited thereto. A person skilled in the art can easily understand the spirit of the present invention based on the above embodiments and make different extensions and changes. However, as long as they do not deviate from the spirit of the present invention, they are all within the protection scope of the present invention.

Claims

1. A fermented milk rich in Lactobacillus plantarum, It is characterized in that The invention comprises the following components in weight percentage: 85-99% high-quality fresh milk, 0.05-0.5% growth promoter, 0.001-0.05% cytosine nucleotide and uracil nucleotide composition, 0.5-10% oligosaccharide, 0.1-0.8% carrageenan, 0.01-0.05% natural vanilla extract, and the rest are high-efficiency fermentation agents; The high-efficiency fermentation agent includes fermentation bacteria, vitamins, minerals and precursor substances, wherein the inoculation amount of the fermentation bacteria is 1.0×10 6 Up to 5.0×10 7 CFU / mL; The fermentation bacteria is any one of highly active Lactobacillus plantarum, Streptococcus thermophilus or Lactobacillus casei; Wherein, the highly active plant lactobacillus is fermented lactobacillus ELF041, and the preservation number of fermented lactobacillus ELF041 is CCTCCNO: M20221240.

2. The fermented milk rich in Lactobacillus plantarum according to claim 1, Features: The growth promoter is a mixture of valine and leucine.

3. A method for producing the fermented milk rich in Lactobacillus plantarum according to claim 1 or 2, It is characterized in that The following steps are involved: S1, raw material selection and pretreatment; Select fresh, pollution-free, high-quality fresh milk with a fat content of 3.0-4.0%, and pre-treat it through a double filter to remove impurities and microorganisms, wherein the pore size of the double filter is ≤0.5μm; S2, batching and mixing; At a temperature of 45-55°C, the pretreated milk and all the above components are mixed uniformly in a high-speed stirrer according to a predetermined ratio, and the stirring speed is controlled at 1000-1500 rpm for 5-10 minutes; S3, homogenization and sterilization; Two-stage homogenization technology is used, with the first stage homogenization pressure of 150-200 bar and the second stage homogenization pressure of 5-10 bar, followed by pasteurization at 85-90℃ for 30 minutes, or high temperature short-time sterilization at 130-135℃ for 4-8 seconds; S4, inoculation and fermentation; On a sterile operating table, a high-efficiency starter is inoculated into cow milk cooled to 40-42° C., and sealed fermentation is performed immediately after inoculation. During the fermentation process, the temperature of the fermentation chamber is controlled to be 41±0.5° C., the fermentation time is 6-10 hours, and intermittent stirring is adopted, stirring once every 30 minutes, each stirring lasts for 2 minutes, the stirring speed is controlled at 50-100 rpm, and a trace amount of oxygen is introduced to promote the growth of Lactobacillus plantarum, wherein the oxygen concentration is controlled at 0.5-1.5%; S5, post-processing and packaging; After fermentation, the fermented milk is immediately cooled to below 4°C and gently stirred to prevent precipitation. It is then aseptically filled into pre-sterilized PET bottles or glass bottles, sealed and stored in a refrigerated environment at 2-6°C.

4. The method for producing fermented milk rich in Lactobacillus plantarum according to claim 3, It is characterized in that Step S1 also includes standardizing the milk to adjust the fat content to 3.2-3.5%, and removing whey protein and other non-fat solid impurities in the milk by centrifugation.

5. The method for producing fermented milk rich in Lactobacillus plantarum according to claim 3, It is characterized in that In step S2, phosphate buffer is also added during the mixing process.

6. The method for producing fermented milk rich in Lactobacillus plantarum according to claim 3, It is characterized in that In step S3, a preheating treatment is performed before homogenization to raise the temperature of the milk to 55-60°C.

7. The method for producing fermented milk rich in Lactobacillus plantarum according to claim 3, It is characterized in that In step S4, the fermentation container is disinfected before inoculation, and a sterile air filtration system is used to ensure that there is no exogenous microbial contamination during the inoculation process. In addition, the pH value and redox potential of the fermentation liquid are monitored.

8. The method for producing fermented milk rich in Lactobacillus plantarum according to claim 3, It is characterized in that In step S5, the post-treatment process also includes homogenization treatment to further refine the texture of the fermented milk.