阅读说明：本技术 一种富含活性物质的长保质期的鲜牛奶及其制备方法 (Active substance-rich fresh milk with long shelf life and preparation method thereof ) 是由 任璐 刘振民 于鹏 张锋华 王辉 姜雪 艾正文 徐杭蓉 于 2021-10-11 设计创作，主要内容包括：本发明涉及液态奶领域,特别是涉及一种富含活性物质的长保质期的鲜牛奶及其制备方法。本发明提供一种鲜牛奶的制备方法,包括：将原料乳进行脱脂处理,以提供稀奶油和脱脂乳；将稀奶油进行高温杀菌处理,以提供灭菌稀奶油；将脱脂乳进行过滤处理,以提供过滤液；将过滤液进行超高压均质处理,以提供均质液；将灭菌稀奶油、均质液混合、无菌均质处理。通过本发明所提供的鲜牛奶的制备方法制备获得的鲜牛奶,是一种富含乳铁蛋白、免疫球蛋白和乳过氧化物酶的鲜牛奶,鲜牛奶可以在低温下保藏超过26天,明显优于现有技术中的其他普通鲜牛奶,具有良好的产业化前景。(The invention relates to the field of liquid milk, in particular to fresh milk rich in active substances and having a long shelf life and a preparation method thereof. The invention provides a preparation method of fresh milk, which comprises the following steps: carrying out degreasing treatment on raw milk to provide cream and skim milk; subjecting cream to a high temperature sterilization process to provide sterilized cream; filtering skim milk to provide a filtrate; carrying out ultrahigh pressure homogenization treatment on the filtrate to provide a homogenized liquid; mixing sterilized cream and homogenized solution, and performing aseptic homogenization treatment. The fresh milk prepared by the preparation method of the fresh milk provided by the invention is the fresh milk rich in lactoferrin, immunoglobulin and lactoperoxidase, can be preserved at low temperature for more than 26 days, is obviously superior to other common fresh milk in the prior art, and has good industrialization prospect.)

1. A method for preparing fresh milk comprises:

1) carrying out degreasing treatment on raw milk to provide cream and skim milk;

2) carrying out high-temperature sterilization treatment on the cream provided in the step 1) to provide sterilized cream;

3) filtering the skim milk provided in the step 1) to provide a filtrate;

4) carrying out ultrahigh pressure homogenization treatment on the filtrate provided in the step 3) to provide a homogenized liquid;

5) mixing the sterilized cream provided by the step 2) and the homogenized liquid provided by the step 4), and carrying out aseptic homogenization treatment.

2. The method for producing fresh milk according to claim 1, wherein the raw milk is raw milk subjected to a concentration treatment.

3. The method for preparing fresh milk according to claim 2, wherein in the concentration treatment, the concentration multiple is 1.2-2.8 times, preferably 1.5-2.5 times;

and/or in the concentration treatment, the temperature of the material is less than or equal to 10 ℃, and preferably 2-6 ℃.

4. The method for preparing fresh milk according to claim 1, wherein the raw milk is selected from one or more of raw milk and fresh milk.

5. The method for preparing fresh milk according to claim 4, wherein the whole milk is selected from whole milk, and the fresh milk is selected from fresh milk, and the total number of bacteria in the fresh milk is less than or equal to 100000cfu/ml, preferably less than or equal to 50000 cfu/ml.

6. The preparation method of fresh milk according to claim 1, wherein in the step 1), the temperature of the materials in the degreasing treatment is 45-55 ℃, preferably 47-50 ℃;

and/or in the step 1), the degreasing treatment is centrifugal degreasing treatment, wherein in the centrifugal degreasing treatment, fat in the material is sufficiently removed.

7. The method for preparing fresh milk according to claim 1, wherein in the step 2), the sterilization temperature in the high-temperature sterilization treatment is 120-140 ℃, preferably 125-137 ℃, and the sterilization time is 4-15 s.

8. The preparation method of fresh milk according to claim 1, wherein in the step 3), the temperature of the material in the filtering treatment is 45-55 ℃, preferably 47-50 ℃;

and/or, in the step 3), the pore diameter of the filter medium used in the filtering treatment is 0.7-0.9 μm;

and/or in the step 3), the filtration treatment is membrane filtration treatment, preferably ceramic membrane filtration treatment, and the outlet pressure of the membrane filtration exudate in the membrane filtration treatment is 1-4 bar, preferably 2-3 bar.

9. The preparation method of fresh milk according to claim 1, wherein in the step 4), the material temperature of the ultrahigh-pressure homogenization treatment is 55-65 ℃, preferably 58-62 ℃, and the homogenization pressure is 250-400 Mpa, preferably 300-370 Mpa.

10. The method for preparing fresh milk according to claim 1, wherein in the step 5), the temperature of the material for homogenizing treatment is 55-65 ℃, and the homogenizing pressure is 15-25 Mpa, preferably 18-22 Mpa.

Technical Field

The invention relates to the field of liquid milk, in particular to fresh milk rich in active substances and having a long shelf life and a preparation method thereof.

Background

Fresh milk, also called pasteurized milk, refers to milk processed by pasteurization. The method aims at keeping the natural nutrition of the milk, the common pasteurization conditions are 72-75 ℃, 15-20 seconds or 80-85 ℃, 10-15 seconds, and the sterilization process is mild, so the method has the characteristics of pure nature, original taste and flavor, activity maintenance and the like, but the quality guarantee period of the product is short, and the product is usually stored for 7-15 days at the temperature of 2-6 ℃. In order to further enlarge the sales radius, some enterprises begin to produce 'pseudo-pasteurized' products, which are sterilized at high temperature for a short time, so that the shelf life of the products is further prolonged, and the products are conveniently sold to markets farther away from the production place. How to develop a fresh milk product which contains abundant nutrition, retains more bioactive substances and is suitable for large-scale transportation in a longer shelf life is always the problem to be solved.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, it is an object of the present invention to provide fresh milk rich in active substances and having a long shelf life and a method for preparing the same, which solve the problems of the prior art.

In order to achieve the above objects and other related objects, the present invention provides a method for preparing fresh milk, comprising:

1) carrying out degreasing treatment on raw milk to provide cream and skim milk;

2) carrying out high-temperature sterilization treatment on the cream provided in the step 1) to provide sterilized cream;

3) filtering the skim milk provided in the step 1) to provide a filtrate;

4) carrying out ultrahigh pressure homogenization treatment on the filtrate provided in the step 3) to provide a homogenized liquid;

5) mixing the sterilized cream provided by the step 2) and the homogenized liquid provided by the step 4), and carrying out aseptic homogenization treatment.

In some embodiments of the invention, the raw milk is raw milk after being subjected to a concentration treatment.

In some embodiments of the present invention, in the concentration treatment, the concentration ratio is 1.2 to 2.8 times, preferably 1.5 to 2.5 times;

and/or in the concentration treatment, the temperature of the material is less than or equal to 10 ℃, and preferably 2-6 ℃.

In some embodiments of the invention, the starting milk is selected from one or more combinations of raw fresh milk.

In some embodiments of the invention the whole milk is selected from whole milk and the raw milk is selected from raw milk in which the total number of bacteria is 100000cfu/ml or less, preferably 50000cfu/ml or less.

In some embodiments of the invention, in the step 1), the temperature of the material in the degreasing treatment is 45-55 ℃, preferably 47-50 ℃;

and/or in the step 1), the degreasing treatment is centrifugal degreasing treatment, wherein in the centrifugal degreasing treatment, fat in the material is sufficiently removed.

In some embodiments of the present invention, in the step 2), the sterilization temperature in the high-temperature sterilization treatment is 120-140 ℃, preferably 125-137 ℃, and the sterilization time is 4-15 s.

In some embodiments of the invention, in the step 3), the temperature of the material in the filtering treatment is 45-55 ℃, preferably 47-50 ℃;

and/or, in the step 3), the pore diameter of the filter medium used in the filtering treatment is 0.7-0.9 μm;

and/or in the step 3), the filtration treatment is membrane filtration treatment, preferably ceramic membrane filtration treatment, and the outlet pressure of the membrane filtration exudate in the membrane filtration treatment is 1-4 bar, preferably 2-3 bar.

In some embodiments of the present invention, in the step 4), the material temperature for the ultrahigh-pressure homogenization treatment is 55 to 65 ℃, preferably 58 to 62 ℃, and the homogenization pressure is 250 to 400Mpa, preferably 300 to 370 Mpa.

In some embodiments of the invention, in the step 5), the material temperature for the homogenization treatment is 55 to 65 ℃, and the homogenization pressure is 15 to 25Mpa, preferably 18 to 22 Mpa.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments, and other advantages and effects of the present invention will be apparent to those skilled in the art from the disclosure of the present specification.

For the sake of brevity, only some numerical ranges are explicitly disclosed herein. However, any lower limit may be combined with any upper limit to form a range not explicitly recited, and any lower limit may be combined with other lower limits to form a range not explicitly recited, as well as any upper limit may be combined with any other upper limit to form a range not explicitly recited. Also, although not explicitly recited, each point or individual value between endpoints of a range is encompassed within the range. Thus, each point or individual value can form a range not explicitly recited as its own lower or upper limit in combination with any other point or individual value or in combination with other lower or upper limits.

In the description herein, it is to be noted that, unless otherwise specified, "above" and "below" are inclusive, and "one or more" of "plural" means two or more.

The above summary of the present invention is not intended to describe each disclosed embodiment or every implementation of the present invention. The following description more particularly exemplifies illustrative embodiments. At various points throughout this application, guidance is provided through a series of embodiments that can be used in various combinations. In various embodiments, the list is merely a representative group and should not be construed as exhaustive.

The invention provides a preparation method of fresh milk in a first aspect, which comprises the following steps:

1) carrying out degreasing treatment on raw milk to provide cream and skim milk;

2) carrying out high-temperature sterilization treatment on the cream provided in the step 1) to provide sterilized cream;

3) filtering the skim milk provided in the step 1) to provide a filtrate;

4) carrying out ultrahigh pressure homogenization treatment on the filtrate provided in the step 3) to provide a homogenized liquid;

5) mixing the sterilized cream provided by the step 2) and the homogenized liquid provided by the step 4), and carrying out aseptic homogenization treatment.

In the preparation method of the fresh milk provided by the invention, the used raw milk can be various raw milk which can be suitable for preparing fresh milk products, for example, raw fresh milk and the like. A person skilled in the art can select suitable whole milk and/or raw fresh milk for use in the preparation methods provided herein, for example, the raw fresh milk may be raw fresh milk in general, and may specifically be raw fresh milk meeting GB-19301 national Standard for food safety milk, and further for example, the total number of bacteria in the raw fresh milk is usually not more than 100000cfu/ml, not more than 80000cfu/ml, not more than 60000cfu/ml, not more than 50000cfu/ml, not more than 40000cfu/ml, not more than 30000cfu/ml, not more than 20000cfu/ml, not more than 10000cfu/ml, preferably not more than 50000 cfu/ml.

In the preparation method of the fresh milk provided by the invention, the used raw milk can be raw milk which is not subjected to concentration treatment or raw milk which is subjected to concentration treatment. Concentration treatment generally refers to a treatment process that reduces the solvent fraction (e.g., water, etc.) in the fluid to be treated, thereby providing a product with a higher solute concentration. The concentration process usually requires the use of appropriate concentration methods and parametric conditions. For example, the concentration treatment may be ro (reverse osmosis) reverse osmosis concentration treatment. For example, in the concentration treatment, the concentration ratio may be 1.2 to 2.8 times, 1.2 to 1.4 times, 1.4 to 1.5 times, 1.5 to 1.6 times, 1.6 to 1.7 times, 1.7 to 1.8 times, 1.8 to 1.9 times, 1.9 to 2.0 times, 2.0 to 2.1 times, 2.1 to 2.2 times, 2.2 to 2.3 times, 2.3 to 2.4 times, 2.4 to 2.5 times, 2.5 to 2.6 times, or 2.6 to 2.8 times, preferably 1.5 to 2.5 times. For another example, in the concentration treatment, the temperature of the material may be 10 ℃ or lower, 0 to 2 ℃, 2 to 4 ℃, 4 to 6 ℃, 6 to 8 ℃, or 8 to 10 ℃, preferably 2 to 6 ℃.

The preparation method of the fresh milk provided by the invention can comprise the following steps: the raw milk is subjected to a degreasing treatment to provide cream and skim milk. The skim treatment generally refers to a treatment method in which cream is partially removed from raw milk to provide a corresponding viscous product (e.g., cream, etc.) having a high cream content and a liquid product (e.g., skim milk, etc.) substantially free of cream. Proper parameter conditions are generally required in the degreasing treatment process. For example, the temperature of the material in the degreasing treatment is 45 to 47 ℃, 47 to 48 ℃, 48 to 49 ℃, 49 to 50 ℃, 50 to 51 ℃, 51 to 53 ℃, or 53 to 55 ℃, preferably 47 to 50 ℃. For another example, the degreasing treatment may be a centrifugal degreasing treatment in which fat in the material is sufficiently removed, and the fat content in skim milk may be less than 0.5%.

The preparation method of the fresh milk provided by the invention can also comprise the following steps: carrying out high-temperature sterilization treatment on the cream provided in the step 1) to provide sterilized cream. The above-mentioned pasteurization treatment generally refers to a treatment method in which proteins and enzymes of microorganisms in a material to be treated are coagulated or denatured by high temperature to be killed, and the pasteurization treatment of a dairy product is generally performed in a short time. For example, in the high-temperature sterilization treatment of the cream, the sterilization temperature in the high-temperature sterilization treatment is 120 to 140 ℃, 120 to 123 ℃, 123 to 125 ℃, 125 to 127 ℃, 127 to 129 ℃, 129 to 131 ℃, 131 to 133 ℃, 133 to 135 ℃, 135 to 137 ℃, or 137 to 140 ℃, preferably 125 to 137 ℃, and the sterilization time may be 4 to 15s, 4 to 6s, 6 to 8s, 8 to 10s, 10 to 12s, or 12 to 15s, and generally speaking, the higher the sterilization temperature, the shorter the sterilization time.

The preparation method of the fresh milk provided by the invention can also comprise the following steps: filtering the skim milk provided in step 1) to provide a filtrate. The filtration process generally refers to a process of allowing fluid (e.g., liquid, gas, etc.) in the material to be processed to permeate through the filter medium under the action of a driving force or other external force, while other substances (e.g., solid particles, etc.) are retained by the filter medium. During the filtration process, the material is usually kept at a suitable temperature so as to achieve the best filtration effect. For example, the temperature of the material in the filtration treatment may be 45 to 55 ℃, 45 to 47 ℃, 47 to 48 ℃, 48 to 49 ℃, 49 to 50 ℃, 50 to 51 ℃, 51 to 53 ℃, or 53 to 55 ℃, and preferably 47 to 50 ℃. During filtration, it is often necessary to use a suitable filter medium to achieve the purpose of filter sterilization. For example, the pore size of the filter medium used in the filtration treatment may be 0.7 to 0.9. mu.m, 0.7 to 0.75. mu.m, 0.75 to 0.8. mu.m, 0.8 to 0.85. mu.m, or 0.85 to 0.9. mu.m. For another example, the filtration treatment may be a membrane filtration treatment, preferably a ceramic membrane filtration treatment. For another example, the outlet pressure of the membrane filtration exudate in the membrane filtration treatment may be 1 to 4bar, 1 to 2bar, 2 to 3bar, or 3 to 4bar, preferably 2 to 3 bar.

The preparation method of the fresh milk provided by the invention can also comprise the following steps: carrying out ultrahigh pressure homogenization treatment on the filtrate provided in the step 3) to provide a homogenized liquid. Homogenization generally refers to a process of micronization and homogenization of a dispersion in a material system (e.g., suspension, emulsion, etc.), and this process generally can simultaneously reduce the size of the dispersion and improve the uniformity of distribution of the dispersion. The homogenization process is generally carried out under appropriate pressure and temperature conditions so that fat separation can be effectively prevented. For example, in the ultrahigh-pressure homogenization treatment performed on the filtrate, the material temperature of the homogenization treatment may be 55 to 65 ℃, 55 to 57 ℃, 57 to 58 ℃, 58 to 59 ℃, 59 to 60 ℃, 60 to 61 ℃, 61 to 62 ℃, 62 to 63 ℃ or 63 to 65 ℃, preferably 58 to 62 ℃, and the homogenization pressure may be 250 to 400Mpa, 250 to 270Mpa, 270 to 290Mpa, 290 to 300Mpa, 300 to 310Mpa, 310 to 320Mpa, 320 to 330Mpa, 330 to 340Mpa, 340 to 350Mpa, 350 to 360Mpa, 360 to 370Mpa, 370 to 380Mpa or 380 to 400Mpa, preferably 300 to 370 Mpa.

The preparation method of the fresh milk provided by the invention can also comprise the following steps: mixing the sterilized cream provided by the step 2) and the homogenized liquid provided by the step 4), and carrying out aseptic homogenization treatment. In this step, the sterilized cream derived from a certain amount of raw milk and the homogenized liquid may be directly mixed in a corresponding ratio (for example, when 30g of sterilized cream and 30ml of homogenized liquid are prepared from 100ml of raw milk, 30g of sterilized cream and 30ml of homogenized liquid may be mixed, or 15g of sterilized cream and 15ml of homogenized liquid may be mixed), or the ratio between them may be appropriately adjusted, for example, the sterilized cream and the homogenized liquid may have a fat content of 0.1% to 4.0%, 0.1% to 0.3%, 0.3% to 0.5%, 0.5% to 1.0%, 1.0% to 1.5%, 1.5% to 2.0%, 2.0% to 2.5%, 2.5% to 3.0%, 3.0% to 3.5%, 3.5% to 4.0%, and/or a protein content of 3.5% to 8.0%, 3.5% to 4.0%, or a protein content of 3.5% to 8.0%, 3.5% to 4.0%, 4.0% -4.5%, 4.5% -5.0%, 5.0% -5.5%, 5.5% -6.0%, 6.0% -6.5%, 6.5% -7.0%, 7.0% -7.5%, or 7.5% -8.0%. The homogenization treatment process generally needs to be performed under appropriate pressure and temperature conditions, so that floating of fat can be effectively prevented, for example, in the ultrahigh-pressure homogenization treatment performed on a mixed solution of sterilized cream and a homogenized liquid, the material temperature of the homogenization treatment may be 55 to 65 ℃, 55 to 57 ℃, 57 to 58 ℃, 58 to 59 ℃, 59 to 60 ℃, 60 to 61 ℃, 61 to 62 ℃, 62 to 63 ℃, or 63 to 65 ℃, preferably 60 to 65 ℃, and the homogenization pressure may be 15 to 25Mpa, 15 to 17Mpa, 17 to 18Mpa, 18 to 19Mpa, 19 to 20Mpa, 20 to 21Mpa, 21 to 22Mpa, 22 to 23Mpa, or 23 to 25Mpa, preferably 18 to 22 Mpa.

In a second aspect, the invention provides fresh milk, which is prepared by the preparation method of the fresh milk provided by the first aspect of the invention. By the preparation method, the required fresh milk can be provided after the obtained liquid phase substance is cooled (for example, cooled to 2-6 ℃, 2-3 ℃, 3-4 ℃, 4-5 ℃ or 5-6 ℃). The fresh milk provided by the application is high-quality fresh milk with extremely low heat treatment intensity, generally has very low furosine, higher protein content, immunoglobulin IgG content and lactoferrin content, and can have a longer quality guarantee period under the condition of low-temperature preservation temperature (for example, less than or equal to 10 ℃, preferably 2-6 ℃, 2-3 ℃, 3-4 ℃, 4-5 ℃ or 5-6 ℃). For example, in the fresh milk, the content of the furosine can be less than or equal to 6mg/100g of protein, and is far lower than the stipulation that the furosine of the common pasteurized milk is less than or equal to 12mg/100g (NY/T939-2005 identification of reconstituted milk in pasteurized milk and UHT sterilized milk), the content of the protein can be more than or equal to 3.4 percent, the content of immunoglobulin IgG can be more than or equal to 260mg/L, the content of lactoferrin can be more than or equal to 70mg/L, the content of lactoperoxidase can be more than or equal to 3000mg/L, and the shelf life time can be more than or equal to 26 days.

The fresh milk prepared by the preparation method of the fresh milk provided by the invention is the fresh milk rich in lactoferrin, immunoglobulin and lactoperoxidase, can be preserved at low temperature for more than 26 days, is obviously superior to other common fresh milk in the prior art, and has good industrialization prospect.

The present application is further illustrated by the following examples, which are not intended to limit the scope of the present application.

The detection methods of protein content, immunoglobulin IgG content, lactoferrin content and lactoperoxidase content used in the examples are as follows:

the detection method for the content of immunoglobulin IgG, the content of lactoferrin and the content of lactoperoxidase refers to the following steps:

T/CSCA 110059-;

the detection method of the content of furfuryl acid used in the examples refers to: NY/T939-2005 identification of reconstituted milk in pasteurized milk and UHT sterilized milk;

the shelf life detection method used in the examples is as follows:

the determination of microorganisms, organoleptic properties, acidity and microorganisms is carried out by cold storage at a predetermined temperature, wherein the organoleptic evaluation, boiling test, acidity, microbiological determination methods are as follows: GB 19645 pasteurized milk of national standard of food safety.

Example 1

In the raw milk (conventional raw milk), the total number of bacterial colonies is 100000 cfu/m;

(1) concentrating all raw milk by RO reverse osmosis at 10 deg.C for 1.2 times to obtain concentrated milk;

(2) preheating concentrated milk at 45 deg.C, centrifuging to defat (fat of skim milk is less than 0.5%, and dilute cream is about 30-40%, the same applies below) to obtain dilute cream and skim milk;

(3) sterilizing the obtained cream at high temperature of 120 deg.C for 15S to obtain sterilized cream;

(4) preheating the obtained skim milk, wherein the preheating temperature is 45 ℃, and after filtering through a ceramic membrane with the aperture of 0.8 micron, the outlet pressure of a membrane filtration exudate is 4bar to obtain a filtrate;

(5) homogenizing the obtained filtrate at ultrahigh pressure of 250MPa and 65 deg.C to obtain homogenized solution;

(6) and (3) mixing the sterilized cream in the step (3) with the homogenized liquid in the step (5), performing aseptic homogenization at 65 ℃ and 25Mpa, cooling, filling and preserving, cooling to 6 ℃, performing aseptic filling, refrigerating, and performing cold storage at 10 ℃ to obtain the cream.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

item	Index (I)
		Protein	3.5％
Immunoglobulin IgG	260mg/L
		Lactoferrin	70mg/L
Lactoperoxidase	3000mg/L
		Furfurin	4.5mg/100g
Shelf life	26 days

Example 2

In the raw milk (conventional raw milk), the total number of bacterial colonies is 50000 cfu/m;

(1) concentrating raw milk by RO reverse osmosis at 2.8 times and 6 deg.C to obtain concentrated milk;

(2) preheating the concentrated milk at 55 deg.C, and centrifuging to obtain cream and skim milk;

(3) sterilizing the obtained cream at ultra-high temperature of 140 deg.C for 4s to obtain sterilized cream;

(4) preheating the obtained skim milk, wherein the preheating temperature is 55 ℃, and after filtering by using a ceramic membrane with the aperture of 0.8 micron, the outlet pressure of a membrane filtration exudate is 1bar to obtain a filtrate;

(5) homogenizing the obtained filtrate at ultrahigh pressure of 400MPa and 55 deg.C to obtain homogenized solution;

(6) and (3) mixing the sterilized cream in the step (3) with the homogenized liquid in the step (5), performing sterile homogenization at 55 ℃ and 15Mpa, cooling, filling and preserving, cooling to 2 ℃, performing sterile filling, refrigerating, and performing cold storage at 6 ℃ to obtain the cream.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

item	Index (I)
		Protein	8％
Immunoglobulin IgG	515mg/L
		Lactoferrin	140mg/L
Lactoperoxidase	6000mg/L
		Furfurin	5.8mg/100g
Shelf life	31 days

Example 3

The total number of bacterial colonies in the raw milk (conventional raw milk) is 60000 cfu/m;

(1) concentrating raw milk by RO reverse osmosis at 2.5 times at 2 deg.C to obtain concentrated milk;

(2) preheating the concentrated milk at 50 ℃, and centrifugally degreasing to obtain cream and skim milk;

(3) sterilizing the obtained cream at high temperature of 125 deg.C for 15s to obtain sterilized cream;

(4) preheating the obtained skim milk, wherein the preheating temperature is 45 ℃, and after filtering through a ceramic membrane with the aperture of 0.8 micron, the outlet pressure of a membrane filtration exudate is 2bar to obtain a filtrate;

(5) homogenizing the obtained filtrate at ultrahigh pressure of 300MPa and 58 deg.C to obtain homogenized solution;

(6) and (3) mixing the sterilized cream in the step (3) with the homogenized liquid in the step (5), performing sterile homogenization at 55 ℃ and 15Mpa, cooling, filling and preserving, cooling to 2 ℃, performing sterile filling, refrigerating, and performing cold storage at 6 ℃ to obtain the cream.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

item	Index (I)
		Protein	6.8％
Immunoglobulin IgG	500mg/L
		Lactoferrin	124mg/L
Lactoperoxidase	3900mg/L
		Furfurin	5.2mg/100g
Shelf life	29 days

Example 4

The total number of bacterial colonies in the raw milk (conventional raw milk) is 60000 cfu/m;

(1) concentrating raw milk by RO reverse osmosis at 1.4 times at 4 deg.C to obtain concentrated milk;

(2) preheating the concentrated milk, wherein the preheating temperature is 47 ℃, and performing centrifugal degreasing to obtain cream and skim milk;

(3) sterilizing the obtained cream at high temperature of 137 deg.C for 4S to obtain sterilized cream;

(4) preheating the obtained skim milk, wherein the preheating temperature is 50 ℃, and after filtering through a ceramic membrane with the aperture of 0.8 micron, the outlet pressure of a membrane filtration exudate is 3bar to obtain a filtrate;

(5) homogenizing the obtained filtrate at ultrahigh pressure of 370Mpa at 62 deg.C to obtain homogenized solution;

(6) and (3) mixing the sterilized cream in the step (3) with the homogenized liquid in the step (5), performing sterile homogenization at 55 ℃ and 18Mpa, cooling, filling and preserving, cooling to 4 ℃, performing sterile filling, refrigerating, and performing cold storage at 4 ℃ to obtain the cream.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

example 5

The total number of bacterial colonies in the raw milk (conventional raw milk) is 20000 cfu/m;

(1) concentrating raw milk by RO reverse osmosis at 1.8 times at 4 deg.C to obtain concentrated milk;

(2) preheating the concentrated milk at 48 ℃, and centrifugally degreasing to obtain cream and skim milk;

(3) sterilizing the obtained cream at high temperature of 137 deg.C for 4s to obtain sterilized cream;

(4) preheating the obtained skim milk, wherein the preheating temperature is 48 ℃, and after filtering by using a ceramic membrane with the aperture of 0.8 micron, the outlet pressure of the membrane-filtered exudate is 2.5bar to obtain filtrate;

(5) homogenizing the obtained filtrate at ultrahigh pressure of 350MPa and 60 deg.C to obtain homogenized solution;

(6) and (3) mixing the sterilized cream in the step (3) with the homogenized liquid in the step (5), performing sterile homogenization at the homogenization temperature of 60 ℃ and the homogenization pressure of 20Mpa, cooling, filling and preserving, cooling to 6 ℃, performing sterile filling, refrigerating, and performing cold storage at the refrigeration temperature of 7 ℃ to obtain the cream.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

item	Index (I)
		Protein	4.0％
Immunoglobulin IgG	3.08mg/L
		Lactoferrin	78mg/L
Lactoperoxidase	3820mg/L
		Furfurin	5.1mg/100g
Shelf life	28 days

Comparative example 1

The raw materials and process used in comparative example 1 were as in example 5, except that the RO reverse osmosis concentration was changed to a flash evaporation concentration technique, and the flash evaporation temperature was about 75 ℃.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

item	Index (I)
		Protein	4.0％
Immunoglobulin IgG	149mg/L
		Lactoferrin	41mg/L
Lactoperoxidase	560mg/L
		Furfurin	10.5mg/100g
Shelf life	15 days

Comparative example 2

The raw materials and process used in comparative example 2 were as described in example 5, except that the 0.8 micron ceramic membrane filtration process was changed to a 1.4 micron ceramic membrane filtration process.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

item	Index (I)
		Protein	4.0％
Immunoglobulin IgG	310mg/L
		Lactoferrin	81mg/L
Lactoperoxidase	3800mg/L
		Furfurin	5.1mg/100g
Shelf life	20 days

Comparative example 3

The raw materials and process used in comparative example 3 were as in example 5 except that the ultra-high pressure homogenization process was omitted.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

item	Index (I)
		Protein	4.0％
Immunoglobulin IgG	315mg/L
		Lactoferrin	83mg/L
Lactoperoxidase	3900mg/L
		Furfurin	4.9mg/100g
Shelf life	12 days

Comparative example 4

The raw materials and process used in comparative example 4 were as described in example 5, except that the ultra-high pressure homogenization process was changed to a thermal sterilization process at a sterilization temperature of 78 ℃ for a sterilization time of 15 seconds.

Detecting the protein content, the immunoglobulin IgG content, the lactoferrin content, the lactoperoxidase content and the furfuryl acid content of the prepared fresh milk, and further detecting the quality guarantee period, wherein the detection results are as follows:

item	Index (I)
		Protein	4.0％
Immunoglobulin IgG	155mg/L
		Lactoferrin	51mg/L
Lactoperoxidase	1200mg/L
		Furfurin	9.6mg/100g
Shelf life	18 days

In conclusion, the present invention effectively overcomes various disadvantages of the prior art and has high industrial utilization value.

The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.