CN102630803A - Humanized milk protein and preparation method thereof - Google Patents

Abstract

The invention discloses a humanized milk protein and a preparation method thereof. The invention adopts cow's milk as a raw material, grades and filters the cow's milk through membranes with different molecular weight cut-offs, mixes the concentrates in proportion, and sprays and dries to directly prepare the breastmilkized cow's milk protein. Breastmilkized milk protein can be directly added to infant formula milk powder and food as a protein raw material. The advantage is that the ratio of casein to whey protein is close to the level of breast milk, which is convenient for infants to digest and utilize.

Description

Humanized milk protein and preparation method thereof

technical field

The invention relates to a milk protein and a preparation method thereof, in particular to a milk protein which can be used for formula milk powder and food for breastmilkized infants and a preparation method thereof.

Background technique

In breast milk protein, casein accounts for about 30%, whey protein accounts for about 70%, of which lactalbumin accounts for about 26%, and basically does not contain lactoglobulin. Cow's milk is the main raw material for the production of infant milk powder, and its protein composition is quite different from that of breast milk. Casein accounts for about 80%, whey protein accounts for about 20%, of which lactalbumin accounts for about 17%, and lactoglobulin accounts for about 43%. %. Milk powder produced directly from cow’s milk forms a hard gel in the human stomach due to the action of acid and enzymes, which has poor digestibility, and milk powder contains more lactoglobulin, which is the cause of allergies substance. The gastrointestinal digestion function of newborns and infants is weak. Excessive casein and lactoglobulin will not only lead to a decrease in the protein utilization rate of infants, but also easily cause allergic reactions.

Using graded membrane technology to process cow's milk, different proteins can be separated according to the molecular weight of proteins in milk, the concentrated solution is mixed in proportion, concentrated and spray-dried, and protein products with a protein composition close to breast milk can be directly produced. It can be directly applied to baby milk powder and food.

Contents of the invention

The object of the present invention is to provide a kind of humanized milk protein and its preparation method.

The breastmilk milk protein provided by the present invention has a protein composition, the ratio of casein to whey protein is 40:60-30:70; lactoglobulin accounts for less than 5% of the whey protein.

The present invention also provides a method for preparing breastmilk milk protein, the preparation method comprising the following steps:

(a) skimming raw milk to obtain skimmed milk;

(b) microfiltering the skim milk to obtain a casein-rich concentrate;

(c) obtaining the whey protein permeate through ultrafiltration of the microfiltration permeate;

(d) The ultrafiltration permeate is subjected to ultrafiltration to obtain a lactalbumin concentrate

(e) mixing (b) and (d) obtained concentrate;

(f) homogeneously sterilizing the mixed solution obtained in (e);

(g) Spray-drying the sterilized mixed solution to obtain humanized milk protein.

In the method, the step (a) further includes filtering the raw milk before skimming, and preheating to 35-40°C.

In the method, in the degreasing step in the step (a), the fat content of the obtained skim milk should be less than 0.1%.

In the method, the microfiltration membrane in the step (b) is treated with a ceramic membrane, and the membrane pore size is 70-80nm. The microfiltration concentration temperature is 20-25° C., the pressure is 0.2-0.3 MPa, and the concentration ratio is 4-5.5 times.

In the method, the step (c) further includes using citric acid to adjust the pH value of the microfiltration permeate to 5.0-5.5 before the ultrafiltration.

In the method, in the ultrafiltration process in the step (c), the material of the ultrafiltration membrane is polyethersulfone, and the molecular weight cut-off is 30kDa. The ultrafiltration concentration temperature is 40-50° C., the ultrafiltration pressure is 0.2-0.3 MPa, and the concentration ratio is 4-5.5 times.

In the method, in the ultrafiltration process in the step (d), the material of the ultrafiltration membrane is polyethersulfone, and the molecular weight cut-off is 10kDa. The ultrafiltration concentration temperature is 40-50° C., the ultrafiltration pressure is 0.2-0.3 MPa, and the concentration ratio is 4-5.5 times.

In the method, in the mixing process in the step (e), the microfiltration concentrate and the lactalbumin concentrate are mixed in a ratio of 1.5:10 to 1:10.

In the method, in the homogenization process described in the step (f), the homogenization pressure is 15-20 MPa.

In the method, in the sterilizing process in the step (f), the sterilizing temperature is 70-75° C., and the time is 15 s.

In the method, the step (g) also includes concentrating the obtained mixed solution to a dry matter content of 40% before spray drying, and then spray drying.

In the method, the spray drying in the step (g) adopts a vertical spray drying tower, the spray drying air inlet temperature is 110~200°C, preferably 120~150°C, the outlet air temperature is 90~105°C, and the spray drying The pressure is 0.18~0.20MPa.

Detailed ways

Example 1

The raw material is the fresh raw milk of the day, which is refrigerated and stored at 4°C.

After filtering, preheat to 40°C, and use a cream separator to separate the fat. The fat content of the obtained skim milk is 0.06%.

The ceramic membrane used for microfiltration and concentration has a membrane pore size of 80nm, the microfiltration temperature is 25°C, the microfiltration pressure is 0.3MPa, and the concentration factor is 4 times.

Ultrafiltration concentrates the microfiltration permeate, adopts polyethersulfone ultrafiltration membrane, the molecular weight cut-off is 30kDa, the ultrafiltration temperature is 50°C, the ultrafiltration pressure is 0.25MPa, and the concentration ratio is 5 times.

Ultrafiltration concentrates the ultrafiltration permeate, using a polyethersulfone ultrafiltration membrane with a molecular weight cut-off of 10kDa, an ultrafiltration temperature of 50°C, an ultrafiltration pressure of 0.25MPa, and a concentration factor of 5.5.

The microfiltration concentrate is mixed with the second step ultrafiltration concentrate at a volume ratio of 1:10.

The mixed solution is homogenized, and the homogenization pressure is 18MPa; after homogenization, it is sterilized, and the sterilization condition is 72°C, 15s.

The air inlet temperature of the spray drying tower is 130°C, the outlet air temperature is 90°C, and the spray pressure is 0.18MPa. The resulting product is human milk protein.

The human milk protein obtained above was analyzed by the national standard method for its protein composition index, and the results are shown in Table 1:

母乳化牛乳蛋白的蛋白组成 surface

Protein composition of human milk protein

The sensory indicators of the above-mentioned breastmilk milk protein made:

1. Color: uniform milky white or slightly yellow;

2. Nourishing smell: It has the unique milky smell of this product, no spoilage smell;

3. Organizational state: uniform powder, no sundries, no lumps, no impurities visible to the naked eye.

Claims (9)

1. emulsified milk albumen, its albumen is formed:

The ratio of casein and lactalbumin is 40:60 ~ 30:70; Wherein lactoglobulin content accounts for protein content of whey and is less than 5%.

2. prepare the method for emulsified milk albumen, comprise the steps:

(a) with raw material milk carry out degreasing obtain defatted milk;

(b) skimmed milk must be rich in caseic concentrate through micro-filtration;

(c) micro-filtration is seen through liquid and get lactalbumin through liquid through ultrafiltration;

(d) ultrafiltration is seen through liquid and get the lactoalbumin concentrate through ultrafiltration

(e) with (b) and (d) the gained concentrate mix;

(f) with the sterilization of (e) gained mixed liquor homogeneous;

(g) with the spray-dried emulsified milk albumen that obtains of the mixed liquor after the sterilization.

3. according to the said method of claim 2, it is characterized in that:

Before also being included in degreasing in the step (a) raw milk is filtered, be preheated to 35 ~ 40 ℃, the fat content of gained skimmed milk should be less than 0.1%.

4. according to the said method of claim 2, it is characterized in that:

Micro-filtration membrane described in the step (b) adopts ceramic membrane to handle, and membrane aperture is 70 ~ 80nm, and said micro-filtration thickening temperature is 20 ~ 25 ℃, and pressure is 0.2 ~ 0.3MPa, and cycles of concentration is 4 ~ 5.5 times.

5. according to the said method of claim 2, it is characterized in that:

Before also being included in ultrafiltration in the step (c), utilize citric acid that the pH value that micro-filtration sees through liquid is transferred to 5.0 ~ 5.5, said ultra-filtration process, the material of milipore filter are polyether sulfone, and molecular cut off is 30kDa; The ultrafiltration thickening temperature is 40 ~ 50 ℃, and ultrafiltration pressure is 0.2 ~ 0.3MPa, and cycles of concentration is 4 ~ 5.5 times.

6. according to the said method of claim 2, it is characterized in that:

Ultra-filtration process described in the step (d), the material of milipore filter are polyether sulfone, and molecular cut off is 10kDa, and the ultrafiltration thickening temperature is 40 ~ 50 ℃, and ultrafiltration pressure is 0.2 ~ 0.3MPa, and cycles of concentration is 4 ~ 5.5 times.

7. according to the said method of claim 2, it is characterized in that:

Mixed process described in the step (e), micro-filtration concentrate and lactoalbumin concentrate are pressed 1.5:10 ~ 1:10 mixed.

8. according to the said method of claim 2, it is characterized in that:

Homogenizing process described in the step (f), homogenization pressure are 15 ~ 20MPa, and said sterilization process, sterilization temperature are 70 ~ 75 ℃, and the time is 15s.

9. according to the said method of claim 2, it is characterized in that:

Also be included in the step (g) and will obtain mixed liquor before the spray-drying to be concentrated into dry matter content be 40%; Carry out spray-drying again; Spray-drying adopts vertical spray drying tower in the step (g), and said spray-drying EAT is 110 ~ 200 ℃, preferred 120 ~ 150 ℃; Leaving air temp is 90 ~ 105 ℃, and atomisation pressure is 0.18 ~ 0.20MPa.