CN111955548B

CN111955548B - Pure probiotic flavored fermented milk and preparation method thereof

Info

Publication number: CN111955548B
Application number: CN202010915333.2A
Authority: CN
Inventors: 肖杨; 刘振民; 徐致远; 苏米亚; 廖文艳
Original assignee: Bright Dairy and Food Co Ltd
Current assignee: Bright Dairy and Food Co Ltd
Priority date: 2020-09-03
Filing date: 2020-09-03
Publication date: 2022-09-02
Anticipated expiration: 2040-09-03
Also published as: CN111955548A

Abstract

The invention discloses pure probiotic flavored fermented milk and a preparation method thereof, wherein the pure probiotic flavored fermented milk comprises the following components in percentage by mass: 2 to 10 percent of sweetening agent, 0.5 to 5 percent of proliferation agent, 0 to 1 percent of stabilizing agent, 0.001 to 0.1 percent of probiotics and the balance of raw milk to 100 percent. The invention also discloses a preparation method thereof, which comprises the steps of preheating the raw milk, adding the proliferation agent, the stabilizer and the sweetening agent, keeping the temperature and stirring, heating and homogenizing the obtained material, sterilizing the material after homogenization, inoculating probiotics in a pollution-free environment after cooling, fermenting at the fermentation temperature of 35-42 ℃ until the acidity of the fermentation end point is 70-90 DEG T to obtain fermented milk, cooling and filling to obtain the pure probiotic flavored fermented milk. The invention realizes the acceleration of the proliferation of probiotics, shortens the fermentation time and improves the production stability and the food safety of products.

Description

Pure probiotic flavored fermented milk and preparation method thereof

Technical Field

The invention belongs to the field of dairy product production, and particularly relates to pure probiotic flavored fermented milk and a production method thereof.

Background

The intestinal tract plays a vital role in human health. In addition to being responsible for the digestion, absorption and metabolism of nutrients, the gut is an important immune and endocrine organ, and is also called the "second brain", which is rich in the enteric nervous system and establishes a connection with the brain via the vagus nerve. More and more researches show that intestinal flora can be regarded as a 'microorganism organ' in the body, and participates in local and systemic physiological processes in various aspects such as metabolism, immunity, incretion, nerves and the like of a host through mechanisms such as the self components, metabolites and derivatives of the flora, and translocation of pathogenic symbiosis bacteria, so that the risks of diseases such as obesity, diabetes, cardiovascular diseases, autoimmune diseases, inflammatory diseases and the like are influenced.

The probiotics are mainly live bacteria preparations which can improve the ecological balance of host intestinal flora, play a beneficial role and improve the health level of the host, and are mainly colonized in oral cavity, intestinal tract, skin and other places of a human body. The probiotics mainly comprise lactobacillus, bifidobacterium, enterococcus, lactococcus, streptococcus, leuconostoc and the like. Research on the effect of probiotics in intestinal tract and influence factors thereof shows that the effect of the probiotics mainly comprises the following steps: promoting digestion and absorption of nutrient substances, maintaining balance of intestinal flora, inhibiting growth and reproduction of pathogenic bacteria, stimulating immune system to improve body resistance, improving lactose utilization of lactose intolerance patients, reducing cholesterol in blood serum, and preventing intestinal diseases.

Currently, the probiotic dairy products commonly found on the market include three major categories: the probiotic fermented lactobacillus beverage is prepared by fermenting and processing probiotics serving as a leavening agent for a long time, and the mainstream product is a refrigerated brown active lactobacillus beverage; secondly, the flavor fermented milk is added with probiotics, the main leaven in the product is usually streptococcus thermophilus and lactobacillus bulgaricus, the addition amount of the probiotics is limited, the number of the probiotics is increased very slowly in the fermentation process, and the number of the probiotics in the product is usually about 107 CFU/g; thirdly, the flavored fermented milk is fermented by single probiotics, the main leavening agent in the product is the probiotics, but the flavor of the product is still obviously different from that of the mainstream fermented milk in the market. Because the fermentation time is long, the risk of contaminating mixed bacteria exists, and the sanitation requirements on equipment and environment in the production process are high.

The development of fermented milk with pure probiotic flavor containing high viable count has the problems that most probiotics grow very slowly in milk, have long lag phase and long total fermentation time, so that the probiotics are very easily polluted by mixed bacteria, and have the problems of difficult application, poor production stability and poor product safety, so that the production stability and food safety need to be improved.

Disclosure of Invention

In order to solve the problems, the invention selects a large amount of food raw materials to preferably select a proliferation agent which can accelerate the proliferation of probiotics, meets the requirements of food regulations and is easy to accept by consumers, and provides the pure probiotic flavored fermented milk with high viable count and the preparation method thereof through reasonable formula and process design.

The invention is realized by the following technical scheme in order to achieve the purpose:

the preparation method of the probiotics-flavored fermented milk comprises the following raw materials in percentage by mass: 2 to 10 percent of sweetening agent, 0.5 to 5 percent of proliferation agent, 0 to 1 percent of stabilizing agent, 0.001 to 0.1 percent of probiotics and the balance of raw milk to 100 percent;

the preparation method comprises the following steps:

(1) preheating the raw milk to 40-60 ℃, adding a proliferation agent, a stabilizing agent and a sweetening agent, and stirring for 10-20 min under heat preservation;

(2) heating the material obtained in the step (1) to 60-70 ℃, and homogenizing under 18-22 MPa, wherein the primary pressure is 16-18 MPa, and the secondary pressure is 2-4 MPa;

(3) sterilizing the material obtained in the step (2), wherein the sterilization temperature is 90-95 ℃, and the sterilization time is 5-60 min;

(4) cooling the material obtained in the step (3) to 35-42 ℃, inoculating probiotics in a pollution-free environment for fermentation at the fermentation temperature of 35-42 ℃ until the acidity of the fermentation end point is 70-90 ℃ T, and obtaining fermented milk;

(5) and (4) cooling the fermented milk obtained in the step (4), and filling to obtain the pure probiotic flavored fermented milk.

Further, the sweetener comprises 1-6% of white granulated sugar and 1-3% of glucose, and the balance of sugar substitutes or other sweet substances, wherein the percentages are mass percentages of the total mass of the raw materials. In the invention, a certain amount of white granulated sugar and glucose are required to be added, because a carbon source which is easy to utilize for the growth of the probiotics needs to be provided. On the premise that the white granulated sugar and the glucose meet the conditions, the specific dosage and the type of the sweetener can be selected according to the flavor requirement and the market orientation of the product.

Furthermore, the raw milk is raw milk or reconstituted milk which meets the national standard of China.

Further, the proliferation agent is one or more of enzymolysis oat flour, solid malt extract, liquid malt extract, rice extract and wheat germ powder.

Further, the stabilizer is one or more of starch, pectin, agar and gelatin; and/or the addition amount of the stabilizer is 0.2-0.5%.

Further, after the sterilization treatment in the step (3), the materials are kept in the fermentation cylinder at the temperature of 90-95 ℃ for 10-50 min, and then are cooled by cold exchange through a jacket of the fermentation cylinder. The sterilization can be adjusted according to the length of the fermentation time, the growth characteristics of the probiotics used and the cleanliness grade of the key production line. If the following conditions are met: the fermentation time is long, the growth lag phase of probiotics is long, the cleanness of the production line from sterilization to the fermentation cylinder is limited, materials can be selected to pass through sterilization equipment, then the materials are continuously kept at 90-95 ℃ for 10-50 min in the fermentation cylinder, and then the materials are cooled through cold exchange of a fermentation cylinder jacket.

Further, the probiotics is one or more of lactobacillus paracasei, lactobacillus casei, lactobacillus rhamnosus, lactobacillus acidophilus, lactobacillus plantarum, bifidobacterium lactis, bifidobacterium bifidum, bifidobacterium longum, bifidobacterium breve, bifidobacterium infantis, bifidobacterium adolescentis, lactobacillus fermentum and lactobacillus helveticus. The probiotic bacteria have to meet the requirements of the following scientific definition: in 2001, the scientific definition of probiotics was proposed by the Food and Agriculture Organization/World Health Organization (FAO/WHO) joint expert committee of the united nations: probiotic bacteria refer to living microorganisms that, when ingested in sufficient quantities, are beneficial to the health of the host. Furthermore, the probiotic bacteria also need to comply with the regulations of China.

Further, after the probiotics are inoculated in the step (4), the initial viable count in the material is 1.0 multiplied by 10 ⁶ CFU/mL-2.0×10 ⁷ CFU/mL. Inoculation of the probiotic bacteria also requires that no traditional fermentation strains or environmental contaminating bacteria are introduced; the equipment for adding the strains needs to be thoroughly cleaned and disinfected, and the cleanliness of the ambient air in an operation room needs to be controlled in the strain adding process.

Further, in the step (4), the fermentation time of the fermentation is 8-15 h.

According to the requirement of flavor adjustment, flavor ingredients such as essence, fruit juice and jam can be added into the product.

On the basis of the common knowledge in the field, the above preferred conditions can be combined randomly to obtain various preferred examples of the invention.

The starting materials used in the present invention are all commercially available.

The invention also provides the fermented milk with the pure probiotic flavor, which is prepared by the preparation method of the fermented milk with the pure probiotic flavor.

The positive progress effects of the invention are as follows:

the functional pure probiotic flavored fermented milk has practical operation value, stable production and high product safety, and can improve the intestinal health and the immunity, and the preparation method thereof, aims at the problem that probiotics are slowly proliferated in milk base materials, adopts proliferation raw materials with stable sources and quality, and is matched with a proper production process, so that the proliferation of the probiotics is accelerated, the fermentation time is shortened, and the production stability and the food safety of the product are improved. Therefore, the probiotic-flavored fermented milk for improving the intestinal health and the immunity of the human body can be widely popularized and benefits the health of the Chinese people.

Drawings

FIG. 1 is a graph showing fermentation curves of example 3 of the present invention and comparative example 2.

Detailed Description

The invention is further illustrated by the following examples, which are not intended to limit the invention thereto. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions.

The present invention is described in further detail below with reference to specific examples.

Example 1

Example 1 raw material formulation the following table 1:

TABLE 1

The preparation procedure for example 1 was as follows:

(1) preheating raw milk to 40 ℃, adding a proliferation agent, a stabilizing agent and a sweetening agent, and stirring for 20min under heat preservation;

(2) heating the material in the step (1) to 60 ℃, and homogenizing under 18MPa of homogenizing pressure, wherein the primary pressure is 16MPa, and the secondary pressure is 2 MPa;

(3) sterilizing the material obtained in the step (2), wherein the sterilization temperature is 90 ℃, and the sterilization time is 5 min;

(4) cooling the material obtained in the step (3) to 35 ℃, inoculating probiotics in a pollution-free environment for fermentation at the fermentation temperature of 35 ℃ for 13 hours until the acidity of the fermentation end point is 80 DEG T, and obtaining fermented milk;

Example 2

Example 2 the raw material formulation is as follows 2:

TABLE 2

The preparation procedure for example 2 was as follows:

(1) preheating raw milk to 60 ℃, adding a proliferation agent, a stabilizing agent and a sweetening agent, and stirring for 10min under heat preservation;

(2) heating the material obtained in the step (1) to 70 ℃, and homogenizing under the homogenizing pressure of 22MPa, wherein the primary pressure is 17MPa, and the secondary pressure is 3 MPa;

(3) sterilizing the material obtained in the step (2), wherein the sterilization temperature is 93 ℃, and the sterilization time is 60 min;

(4) and (4) cooling the material obtained in the step (3) to 38 ℃, inoculating probiotics in a pollution-free environment for fermentation at 38 ℃, and fermenting for 8 hours until the acidity of the fermentation end point is 70 DEG T to obtain the fermented milk.

Example 3

Example 3 the raw material formulation is as follows 3:

TABLE 3

The preparation procedure for example 3 was as follows:

(1) preheating the raw milk to 50 ℃, adding a proliferation agent, a stabilizing agent and a sweetening agent, and stirring for 15min under heat preservation;

(2) heating the material obtained in the step (1) to 65 ℃, and homogenizing under the homogenizing pressure of 20MPa, wherein the primary pressure is 16MPa, and the secondary pressure is 4 MPa;

(3) sterilizing the material obtained in the step (2), wherein the sterilization temperature is 90 ℃, and the sterilization time is 10 min;

(4) and (4) cooling the material obtained in the step (3) to 37 ℃, inoculating probiotics in a pollution-free environment for fermentation at the fermentation temperature of 37 ℃ for 12 hours until the acidity of the fermentation end point is 75 DEG T, and obtaining the fermented milk.

Example 4

The raw material formulation of example 4 is as follows:

TABLE 4

The preparation procedure for example 4 was as follows:

(1) preheating raw milk to 45 ℃, adding a proliferation agent, a stabilizing agent and a sweetening agent, and stirring for 18min under heat preservation;

(2) heating the material in the step (1) to 63 ℃, and homogenizing under 18MPa of homogenizing pressure, wherein the primary pressure is 16MPa, and the secondary pressure is 2 MPa;

(3) sterilizing the material obtained in the step (2), wherein the sterilization temperature is 93 ℃, and the sterilization time is 30 min;

(4) cooling the material obtained in the step (3) to 36 ℃, inoculating probiotics in a pollution-free environment for fermentation at the fermentation temperature of 36 ℃ for 11h until the acidity of the fermentation end point is 90 DEG T, and obtaining fermented milk;

Example 5

The raw material formulation of example 5 is as follows:

TABLE 5

The preparation procedure for example 5 was as follows:

(1) preheating raw milk to 55 deg.C, adding proliferation agent, stabilizer, and sweetener, stirring for 16 min;

(2) heating the material obtained in the step (1) to 66 ℃, and homogenizing under the homogenizing pressure of 18MPa, wherein the primary pressure is 16MPa, and the secondary pressure is 2 MPa;

(3) sterilizing the material obtained in the step (2), wherein the sterilization temperature is 94 ℃, and the sterilization time is 40 min;

(4) cooling the material obtained in the step (3) to 37 ℃, inoculating probiotics in a pollution-free environment for fermentation at 42 ℃ for 10h until the acidity of the fermentation end point is 85 DEG T, and obtaining fermented milk;

Comparative example 1

A pure probiotic flavored fermented milk is prepared by adding no wheat germ powder in the raw material composition, supplementing part of the wheat germ powder in the formula with water, and fermenting for 26 hours until the final acidity is 80 DEG T, wherein the rest is the same as in example 1.

Comparative example 2

A fermented milk with probiotic flavor is prepared by adding water to supplement part of raw materials without enzymolysis oat flour and solid malt extract, fermenting for 18 hours to reach an end acidity of 75 ° T, and performing the same operation as in example 3.

Effect example 1

The pure probiotic flavored fermented milk products of examples 1 and 3 and controls 1 and 2 were subjected to the measurement of the end point acidity, the end point pH, the number of live probiotics, and the sensory evaluation of flavor preference, and all evaluation results are shown in table 6.

The sensory evaluation is carried out by 20 persons, the flavor preference degree of the product is graded (0-5 points, 5 points are full points, which indicates the best evaluation), and the average points are counted.

The method for measuring the number of the live bacteria of the probiotics adopts a method for measuring the total number of the lactic acid bacteria in food safety national standard food microbiology inspection lactic acid bacteria inspection GB 4789.35-2016.

TABLE 6 comparison of end-point acidity and fermentation time

As shown in table 6, the addition of the growth promoter of this patent resulted in the same end-point acidity (80 ° T), which shortened the fermentation time by half in example 1 (13 hours) compared to comparative example 1 (26 hours), and the viable counts of probiotics were very close. Similarly, by adding the proliferation agent of this patent, the same end-point acidity (75 ° T) was achieved, example 3 (12 hours) shortened the fermentation time by 6 hours compared to comparative example 2 (18 hours), and the viable counts of probiotics were very close. Therefore, the growth and reproduction speed of the probiotics is obviously increased by adding the proliferation agent, so that the risk of contamination in the fermentation process is reduced, and the production stability and safety are improved; on the other hand, the fermentation time is shortened, and the production efficiency is improved. From the flavor evaluation results, it was found that the effect of the addition of the proliferation agent on the flavor was very limited, and that the proliferation agent added was a cereal material widely accepted by consumers.

As shown in FIG. 1, the fermentation curves of example 3 and comparative example 2 were measured using an icinac device, and the total fermentation time was uniformly adjusted to 18 hours, resulting in the fermentation curves of both as shown in FIG. 1. The pH reached 5.5, which took 8 hours for example 3 and 10.3 hours for comparative example 2. It can be seen that the lag phase of example 3 is shortened by 2.3 hours compared to comparative example 2, which greatly reduces the risk of contamination.

In conclusion, the probiotic fermented milk produced by the related technology has high probiotic viable count, and the technology also has the advantages of short fermentation time, strong practical production operability, stable production and high product safety.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The preparation method of the fermented milk with the flavor of the pure probiotics is characterized in that the raw materials comprise the following components in percentage by mass: 2 to 10 percent of sweetening agent, 0.5 to 5 percent of proliferation agent, 0 to 1 percent of stabilizing agent, 0.001 to 0.1 percent of probiotics and the balance of raw milk to 100 percent; the proliferation agent is one or more of solid malt extract, liquid malt extract, rice extract and wheat germ powder; the probiotics are one or more of lactobacillus paracasei, lactobacillus casei, lactobacillus rhamnosus, lactobacillus acidophilus, lactobacillus plantarum, bifidobacterium lactis, bifidobacterium bifidum, bifidobacterium longum, bifidobacterium breve, bifidobacterium infantis, bifidobacterium adolescentis, lactobacillus fermentum and lactobacillus helveticus;

the preparation method comprises the following steps:

(2) heating the material obtained in the step (1) to 60-70 ℃, and homogenizing under the homogenizing pressure of 18-22 MPa, wherein the primary pressure is 16-18 MPa, and the secondary pressure is 2-4 MPa;

(5) and (5) cooling the fermented milk obtained in the step (4), and filling to obtain the probiotic-flavored fermented milk.

2. The preparation method of the probiotics-flavored fermented milk according to claim 1, wherein the sweetener comprises 1-6% of white granulated sugar and 1-3% of glucose, and the percentages are mass percentages of the total mass of the raw materials.

3. The method of producing fermented milk with a pure probiotic flavor according to claim 1, wherein the raw milk is raw milk or reconstituted milk.

4. The method for preparing probiotic-flavored fermented milk according to claim 1, wherein the stabilizer is one or more of starch, pectin, agar and gelatin; and/or the addition amount of the stabilizer is 0.2-0.5%.

5. The method for preparing fermented milk with pure probiotic flavor according to claim 1, wherein after the sterilization treatment in step (3), the material is kept at 90-95 ℃ for 10-50 min in a fermentation cylinder, and then cooled by cooling through jacket cooling exchange of the fermentation cylinder.

6. The method for preparing fermented milk with pure probiotic flavor according to claim 1, wherein the initial viable count of the material after inoculation of probiotic bacteria in step (4) is 1.0 x 10 ⁶ CFU/mL-2.0×10 ⁷ CFU/mL。

7. The method for preparing probiotic-flavored fermented milk according to claim 1, wherein the fermentation time of the fermentation in step (4) is 8-15 h.

8. A probiotic-flavored fermented milk produced by the method for producing a probiotic-flavored fermented milk according to any one of claims 1 to 7.