CN112741154A - Formula liquid milk for premature infants and preparation method thereof - Google Patents

Abstract

A premature infant formula liquid milk and a preparation method thereof belong to the technical field of premature infant formula food processing. In order to solve the problems of troublesome dissolving, inconvenient carrying when people go out, non-uniform concentration and potential health safety hazard of the traditional premature infant formula milk powder, the invention provides the premature infant formula liquid milk and the preparation method thereof, wherein the liquid milk is prepared from raw milk, skim milk, compound vegetable oil, whey protein powder, desalted whey powder, lactose, glucose polymer, compound vitamins, compound mineral substances, nucleotide, taurine, lactoferrin, bifidobacterium animalis Bb-12 and food additives. The premature infant formula liquid milk provided by the invention does not need to be mixed, and is convenient to eat, more uniform in concentration, more sanitary and safer compared with the traditional premature infant formula milk powder.

Description

Formula liquid milk for premature infants and preparation method thereof

Technical Field

The invention relates to formula liquid milk for premature infants and a preparation method thereof, belonging to the technical field of formula food processing for premature infants.

Background

Preterm infants are neonates with gestational age less than 37 weeks, i.e., neonates with gestational age less than 259 days. The premature infant born in each year in China is about 100 ten thousand, the premature infant needs high energy supply to make up for the low birth weight, the premature infant can grow at a growth speed exceeding that of a full-term infant after birth, the sucking and swallowing reflex of the premature infant is not perfect, the gastrointestinal secretion and the digestive function are weak, and the digestive function disorder and the nutritional disorder are easily caused. Meanwhile, premature babies cannot fully absorb the nutrients in mothers, so that the growth and storage requirements cannot be met, the problems of incomplete development of tissues and organs, incomplete function and low resistance are easily caused, and the growth, development and digestive ability are poor due to the fact that nutrients required for growth cannot be timely supplemented after birth. The correct feeding of premature infants means that the premature infants need to be fed correctly to meet the requirements of growth and development because the premature infants need to be fed correctly not only to avoid dysplasia and long-term cognitive behavior caused by insufficient essential nutrients and conditional essential nutrients, but also to avoid the risk that overnutrition may increase metabolic diseases such as hypertension, hyperlipidemia, type II diabetes and the like after adults.

The infant formula liquid milk is internationally recognized as one of the most advanced infant foods at present, represents a brand new feeding concept, is highly concerned by the industry since the market, is relatively strange for most people, and is a new thing. Foreign enterprises such as the minister of Meizan, the Yapei, the love of Taimei, the cowshed and the like have own brands of infant formula liquid milk for a long time, and have been produced and sold for more than ten years, but domestic consumers have little knowledge of the brands. Currently, infant formula liquid milk is being produced and sold in many countries around the world, such as the united states, finland, etc., which are becoming new players in the infant formula market.

The infant formula liquid milk becomes a new pet in the infant formula food market, and mainly has the advantages that firstly, the infant formula liquid milk does not need to be brewed, a lot of time is saved, the infant formula liquid milk has great attraction to office workers, secondly, compared with the brewed infant formula milk powder, the concentration of the infant formula liquid milk is uniform, the infant formula liquid milk is convenient to feed and suitable for being carried outdoors, and most importantly, the infant formula liquid milk is safe and sanitary, and is more beneficial to healthy growth of infants.

At present, infant formula liquid milk in domestic and foreign markets is mainly divided into three segments (the segment 1 is 0-6 months old, the segment 2 is 6-12 months old, and the segment 3 is 12-36 months old), and formula liquid milk products for premature infants are not provided, so that the research and development of the formula liquid milk for premature infants are vital, theoretical basis is provided for production, and technical guidance is provided for production.

Disclosure of Invention

The invention provides a premature formula liquid milk and a preparation method thereof, and aims to solve the problems that the traditional premature formula milk powder is troublesome to prepare, inconvenient to carry when people go out, non-uniform in concentration and hidden health and safety hazards exist. The formula liquid milk for the premature infant is prepared from the following raw materials in percentage by volume based on the prepared liquid milk: the mass concentration of raw milk is 62-115g/L, the mass concentration of skim milk is 62-65g/L, the mass concentration of compound vegetable oil is 11.6-28.8g/L, the mass concentration of whey protein powder is 6.5-7.5g/L, the mass concentration of desalted whey powder is 91-100g/L, the mass concentration of lactose is 22.5-58.5g/L, the mass concentration of glucose polymer is 2.5-6.5g/L, the mass concentration of compound vitamin is 0.25-0.5g/L, the mass concentration of compound mineral is 0.2-0.5g/L, the mass concentration of nucleotide is 0.05-0.09g/L, the mass concentration of taurine is 0.4-0.5mg/L, the mass concentration of lactoferrin is 0.05-0.13g/L, the mass concentration of animal bifidobacterium Bb-12 is 1800 white matter/L, the mass concentration of the food additive is 0.95-1.02 g/L.

Preferably, the compound vegetable oil is composed of soybean oil, corn oil, low erucic acid rapeseed oil, coconut oil and high oleic acid sunflower seed oil, and the mass ratio of the soybean oil, the corn oil, the low erucic acid rapeseed oil, the coconut oil and the high oleic acid sunflower seed oil is 5:37:23:19: 15.

Preferably, the compound vitamin is composed of vitamin A, vitamin D, vitamin K, vitamin E, vitamin B1, vitamin B2, vitamin B6, vitamin B12, nicotinamide, folic acid, pantothenic acid, vitamin C, biotin and choline, and the mass ratio of the vitamin A, the vitamin D, the vitamin K, the vitamin E, the vitamin B1, the vitamin B2, the vitamin B6, the vitamin B12, the nicotinamide, the folic acid, the pantothenic acid, the vitamin C, the biotin and the choline is 31:0.57:0.9:370:12.6:18.7:9.6:0.017:102.5:3.55:69:1630: 3429.

Preferably, the compound mineral is composed of sodium, potassium, copper, magnesium, iron, zinc, manganese, calcium, phosphorus, iodine, chlorine and selenium, and the mass ratio of sodium, potassium, copper, magnesium, iron, zinc, manganese, calcium, phosphorus, iodine, chlorine and selenium is 3841:8213:5.71:859:114:111:0.43:7430:4290:1.86:82130: 0.17.

Preferably, based on the volume of the prepared liquid milk, the mass concentration of the soybean lecithin in the food additive is 0.5-0.52g/L, the mass concentration of the monoglyceride and diglyceride fatty acid ester is 0.45-0.5g/L, the mass concentration of calcium carbonate is 1-1.5mg/L, and the mass concentration of calcium bicarbonate is 0.05-0.1 mg/L.

Preferably, the ratio of the total mass of whey protein to the total mass of casein in raw milk and skim milk is (5-6): 1.

the preparation method of the formula liquid milk for the premature infant comprises the following steps:

(1) filtering raw milk;

(2) mixing and dissolving the raw milk, the skim milk, the whey protein powder, the desalted whey powder, the lactose, the glucose polymer, the compound mineral, the nucleotide, the taurine, the lactoferrin, the bifidobacterium animalis Bb-12, the calcium carbonate and the calcium monohydrogen phosphate in the food additive and water after the filtration in the step (1) to obtain a water-soluble ingredient solution;

(3) adding the compound vitamins, soybean lecithin and mono-diglycerol fatty acid ester in the food additive into the compound vegetable oil, and mixing and dissolving the mixture to obtain a fat-soluble ingredient solution;

(4) mixing the water-soluble ingredient solution in the step (2) and the fat-soluble ingredient solution in the step (3), and adding water to a constant volume to reach the final concentration of each component;

(5) homogenizing the solution with constant volume in the step (4) under high pressure;

(6) putting the material homogenized under high pressure in the step (5) into a glass container, and sealing;

(7) sterilizing the container filled with the materials in the step (6);

(8) and (5) cooling the sterilized product in the step (7) to obtain a finished product.

Preferably, the filtration in step (1) is performed by using a double-layer gauze with a pore size of 44 meshes.

Preferably, the high-pressure homogenizing pressure in the step (5) is 25-35 Mpa.

Preferably, the sterilization condition in the step (7) is that the temperature is 110-120 ℃, and the sterilization time is 10-15 min.

Advantageous effects

1. The premature infant formula liquid milk disclosed by the invention does not need to be prepared, is convenient to eat, has more uniform concentration and is more sanitary and safe compared with the traditional premature infant formula milk powder;

2. the weight ratio of the whey protein to the milk casein in the formula liquid milk for the premature infant is (5-6): 1, the kidney burden is reduced, and the absorption of premature infants is facilitated;

3. the skim milk is added into the liquid milk in the formula of the premature infant to replace the traditional skim milk powder, so that the skim milk more retains the original nutrient substances in the milk compared with the skim milk powder;

4. the skim milk is added into the liquid milk in the formula of the premature infant, and the fat is filled with the compound vegetable oil, so that the healthy proportion of saturated fatty acid and unsaturated fatty acid is ensured, the digestion and absorption are promoted, and the constipation of the premature infant is reduced;

5. the glucose polymer replaces part of lactose, is glycogen formed by connecting a plurality of monomeric glucose through glycosidic bonds, and can be converted into the monomeric glucose which is beneficial to the absorption of an organism through the glycogen;

6. the bifidobacterium animalis Bb-12 added into the liquid milk in the formula of the premature infant contains beta-galactosidase, and compared with bifidobacterium lactis HN-019 and bifidobacterium lactis Bi-07, the bifidobacterium animalis Bb-12 has higher survival rate, can better maintain intestinal lactose fermentation and promote lactose decomposition;

7. the liquid milk in the formula of the premature infant is added with taurine, so that the brain development, nerve conduction and visual function improvement of the premature infant are promoted;

8. the nucleotide is added into the formula liquid milk for premature infants to promote the growth of gastrointestinal tracts and improve the immunity;

9. lactoferrin is added into the formula liquid milk for the premature infant, so that the lactoferrin can regulate the running and storage of iron ions in a body, promote the proliferation of erythrocytes, promote the growth of bones, promote the proliferation and differentiation of epithelial cells of the small intestine and regulate the immune function of an organism;

10. according to the invention, an autoclave is used for in-bottle sterilization, the sterilization temperature is 110-120 ℃, the sterilization time is 10-15 min, and compared with an ultrahigh temperature instant sterilization method, the sterilization method has a better sterilization effect and is more suitable for feeding premature babies.

Detailed Description

The present invention will be further described with reference to the following specific examples, but the present invention is not limited to these examples.

The following examples relate to the following raw material information:

glucose polymers were purchased from Henan Nolan environmental technologies, Inc.;

bifidobacterium animalis was purchased from Sairantoze Biotech Ltd;

nucleotides were purchased from shanxi morning bioscience, ltd;

the compound vegetable oil is composed of soybean oil, corn oil, low erucic acid rapeseed oil, coconut oil and high oleic acid sunflower seed oil, and the mass ratio of the soybean oil, the corn oil, the low erucic acid rapeseed oil, the coconut oil and the high oleic acid sunflower seed oil is 5:37:23:19: 15. The compound vegetable oil used in the invention is purchased from Hebei Jiafeng vegetable oil Co Ltd;

the compound vitamin is composed of vitamin A, vitamin D, vitamin K, vitamin E, vitamin B1, vitamin B2, vitamin B6, vitamin B12, nicotinamide, folic acid, pantothenic acid, vitamin C, biotin and choline, and the mass ratio of the vitamin A, the vitamin D, the vitamin K, the vitamin E, the vitamin B1, the vitamin B2, the vitamin B6, the vitamin B12, the nicotinamide, the folic acid, the pantothenic acid, the vitamin C and the choline is 31:0.57:0.9:370:12.6:18.7:9.6:0.017:102.5:3.55:69:1630: 3429. The compound vitamin used in the invention is purchased from Guangzhou Shuowei food science and technology company;

the compound mineral substance is composed of sodium, potassium, copper, magnesium, iron, zinc, manganese, calcium, phosphorus, iodine, chlorine and selenium, and the mass ratio of sodium, potassium, copper, magnesium, iron, zinc, manganese, calcium, phosphorus, iodine, chlorine and selenium is 3841:8213:5.71:859: 111:0.43:7430:4290:1.86:82130: 0.17. The compound mineral used in the invention is purchased from Guangzhou Shuowei food science and technology company;

example 1. preterm formula liquid milk.

The premature infant formula liquid milk described in this embodiment is prepared by taking the prepared liquid milk volume as a reference, and comprises raw milk with a mass concentration of 85g/L, skim milk with a mass concentration of 63g/L, compound vegetable oil with a mass concentration of 20g/L, whey protein powder with a mass concentration of 7g/L, desalted whey powder with a mass concentration of 95g/L, lactose with a mass concentration of 40g/L, glucose polymer with a mass concentration of 4g/L, compound vitamin with a mass concentration of 0.35g/L, compound mineral with a mass concentration of 0.35g/L, nucleotide with a mass concentration of 0.07g/L, taurine with a mass concentration of 0.45mg/L, lactoferrin with a mass concentration of 0.1g/L, bifidobacterium animalis with a mass concentration of 1400/L, and food additive with a mass concentration of 1 g/L.

The preparation method comprises the following specific steps:

(1) filtering raw milk by using double-layer gauze with the aperture of 44 meshes;

(2) mixing and dissolving the raw milk, the skim milk, the whey protein powder, the desalted whey powder, the lactose, the glucose polymer, the compound mineral, the nucleotide, the taurine, the lactoferrin, the bifidobacterium animalis Bb-12, the calcium carbonate and the calcium monohydrogen phosphate in the food additive and water after the filtration in the step (1) to obtain a water-soluble ingredient solution;

(3) adding the compound vitamins, soybean lecithin and mono-diglycerol fatty acid ester in the food additive into the compound vegetable oil, and mixing and dissolving the mixture to obtain a fat-soluble ingredient solution;

(4) mixing the water-soluble ingredient solution in the step (2) and the fat-soluble ingredient solution in the step (3), and fixing the volume to the final concentration of each component;

(5) homogenizing the solution with the constant volume in the step (4) at high pressure of 30 MPa;

(6) putting the material homogenized under high pressure in the step (5) into a glass container, and sealing;

(7) sterilizing the container filled with the materials in the step (6) at 115 ℃ for 13 min;

(8) and (5) cooling the sterilized product in the step (7) to obtain a finished product.

Example 2 preterm formula liquid milk.

The premature infant formula liquid milk described in this embodiment is prepared by taking the prepared liquid milk volume as a reference, wherein the raw milk mass concentration is 62g/L, the skim milk mass concentration is 65g/L, the compound vegetable oil mass concentration is 11.6g/L, the whey protein powder mass concentration is 7.5g/L, the desalted whey powder mass concentration is 91g/L, the lactose mass concentration is 58.5g/L, the glucose polymer mass concentration is 2.5g/L, the compound vitamin mass concentration is 0.5g/L, the compound mineral mass concentration is 0.2g/L, the nucleotide mass concentration is 0.09g/L, the taurine mass concentration is 0.4mg/L, the lactoferrin mass concentration is 0.13g/L, the bifidobacterium animalis Bb-12 mass concentration is 1000 g/L, and the food additive mass concentration is 1.02 g/L.

The preparation method comprises the following specific steps:

(1) filtering raw milk by using double-layer gauze with the aperture of 44 meshes;

(2) mixing and dissolving the raw milk, the skim milk, the whey protein powder, the desalted whey powder, the lactose, the glucose polymer, the compound mineral nucleotide, the taurine, the lactoferrin and the bifidobacterium animalis Bb-12 which are filtered in the step (1), the calcium carbonate and the calcium monohydrogen phosphate in the food additive and water to obtain a water-soluble ingredient solution;

(3) adding the compound vitamins, soybean lecithin and mono-diglycerol fatty acid ester in the food additive into the compound vegetable oil, and mixing and dissolving the mixture to obtain a fat-soluble ingredient solution;

(4) mixing the water-soluble ingredient solution in the step (2) and the fat-soluble ingredient solution in the step (3), and fixing the volume to the final concentration of each component;

(5) homogenizing the solution with constant volume in the step (4) at high pressure, wherein the pressure of the high-pressure homogenization is 35 Mpa;

(6) putting the material homogenized under high pressure in the step (5) into a glass container, and sealing;

(7) sterilizing the container filled with the materials in the step (6) at 120 ℃ for 15 min;

(8) and (5) cooling the sterilized product in the step (7) to obtain a finished product.

Example 3. preterm formula liquid milk.

The premature infant formula liquid milk described in this embodiment is prepared by taking the prepared liquid milk volume as a reference, wherein the raw milk mass concentration is 115g/L, the skim milk mass concentration is 62g/L, the compound vegetable oil mass concentration is 28.8g/L, the whey protein powder mass concentration is 6.5g/L, the desalted whey powder mass concentration is 100g/L, the lactose mass concentration is 22.5g/L, the glucose polymer mass concentration is 6.5g/L, the compound vitamin mass concentration is 0.25g/L, the compound mineral mass concentration is 0.5g/L, the nucleotide mass concentration is 0.05g/L, the taurine mass concentration is 0.5mg/L, the lactoferrin mass concentration is 0.05g/L, the bifidobacterium animalis Bb-12 mass concentration is 1800 g/L, and the food additive mass concentration is 0.95-1.02 g/L.

The preparation method comprises the following specific steps:

(1) filtering raw milk by using double-layer gauze with the aperture of 44 meshes;

(2) mixing and dissolving the raw milk, the skim milk, the whey protein powder, the desalted whey powder, the lactose, the glucose polymer, the compound mineral, the nucleotide, the taurine, the lactoferrin, the bifidobacterium animalis Bb-12, the calcium carbonate and the calcium monohydrogen phosphate in the food additive and water after the filtration in the step (1) to obtain a water-soluble ingredient solution;

(3) adding the compound vitamins, soybean lecithin and mono-diglycerol fatty acid ester in the food additive into the compound vegetable oil, and mixing and dissolving the mixture to obtain a fat-soluble ingredient solution;

(4) mixing the water-soluble ingredient solution in the step (2) and the fat-soluble ingredient solution in the step (3), and fixing the volume to the final concentration of each component;

(5) homogenizing the solution with constant volume in the step (4) at high pressure of 25 Mpa;

(6) putting the material homogenized under high pressure in the step (5) into a glass container, and sealing;

(7) sterilizing the container filled with the materials in the step (6) at the temperature of 110 ℃ for 10 min;

(8) and (5) cooling the sterilized product in the step (7) to obtain a finished product.

Comparative example 1 high oil preterm infant formula liquid milk.

Example 1 is repeated, and the difference from example 1 is that in the liquid milk raw material described in the comparative example, the weight concentration of the compounded vegetable oil is 30g/L based on the volume of the prepared liquid milk.

Comparative example 2 low oil preterm formula liquid milk.

Example 1 is repeated, and the difference from example 1 is that in the liquid milk raw material described in the comparative example, the weight concentration of the compounded vegetable oil is 10g/L based on the volume of the prepared liquid milk.

Comparative example 3 full fat preterm formula liquid milk.

According to the formula liquid milk for the premature infant, based on the volume of the prepared liquid milk, each 1000L of the formula liquid milk contains 134.02kg of fresh raw milk, 7.3kg of whey protein powder, 40.58kg of desalted whey powder, 52.8kg of lactose, 6.5kg of glucose polymer, 0.27kg of compound vitamin, 0.22kg of compound mineral, 0.08kg of nucleotide and 0.12kg of lactoferrin.

The specific preparation method is the same as that of example 1.

Comparative example 4. preterm formula liquid milk fortified with no taurine, nucleotides, lactoferrin.

The formula liquid milk for the premature infant described in this embodiment contains, based on the volume of the prepared liquid milk, 95.27kg of fresh raw milk, 50.26kg of skim milk, 20.2kg of compound vegetable oil, 7kg of whey protein powder, 73.6kg of desalted whey powder, 43.5kg of glucose polymer, 0.27kg of compound vitamin, and 0.22kg of compound mineral substance per 1000L.

The specific preparation method is the same as that of example 1.

To demonstrate the effects that can be obtained by the present invention, the following experiments were carried out:

sensory evaluation and mouse experiments were carried out using the preterm formula liquid milk prepared in example 1, comparative example 1 and comparative example 2 to demonstrate that the formula liquid milk suitable for preterm infants is good in homogeneity and can promote digestive absorption and development of brain nerves.

1. Sensory evaluation: selecting 10 professionals with dairy product expertise and receiving sensory evaluation training for sensory evaluation.

The grading standard comprises taste, smell, tissue state and color, and the proportion of the taste, the smell, the tissue state and the color is respectively 60, 30 and 10 for sensory grading.

TABLE 1 sensory evaluation Table

Single item score: when calculating the score, one of the highest score and the lowest score should be removed from the total singles scores. The calculation is carried out according to the following formula, and the result is an integer.

Single score is the sum of the remaining single scores/(assessor number-2)

Total points are as follows: when calculating the score, one highest score and one lowest score should be removed from the total score. Calculated according to the following formula. The result is an integer.

Total score is the sum of the remaining total scores/(number of assessors-2)

The following table is the sensory evaluation results:

TABLE 2 sensory evaluation Total score of the examples

Experimental group	Total score
		Example 1 (Compound vegetable oil medium dose)	88
Comparative example 1 (high dose of compounded vegetable oil)	98
		Comparative example 2 (Low dose of compounded vegetable oil)	95

According to table 2, it can be found that when the compound vegetable oil is added in the medium-dose group, the sensory evaluation score of the preterm formula liquid milk is up to 98 points, and the color, the taste and the tissue state of the product are more suitable for consumers and preterm infants compared with the high-dose group and the low-dose group.

2. Mouse experiment

(1) Experimental Material

Experimental materials: selecting SPF-grade healthy Kunming mice with the weight of 20 +/-0.5 g, using male and female simultaneously, adapting for 3 days under natural illumination at the room temperature of 21 +/-1 ℃ and the indoor relative humidity RH (32% +/-2%) in an experimental environment, feeding the prepared feed during the adaptation period, freely feeding water, and stopping feeding in the morning on the 4 th day.

(2) Experimental methods and procedures

150 mice, male and female halves, were randomly divided into 5 groups. The following formulated liquid milks, example 1, comparative example 2, comparative example 3, and comparative example 4 were fed, respectively.

Quantitatively filling 0.5mL of formula liquid milk into each mouse, slaughtering three animals in each group at 0.5h, 1h, 2h and 4h, rapidly opening abdominal cavity, taking out stomach and duodenum, and storing small intestine in ice box for determining fat digestibility, glucose polymer digestibility and protein digestibility.

1) Fat digestibility determination

Flushing the digestive tract with normal saline, collecting gastric juice and intestinal juice in normal saline, and measuring the fat content in each sample by an acid hydrolysis method to obtain the total fat content of the gavage emulsion as the digestibility.

Fat digestibility (%) - (total fat content in sample-gastrointestinal fat content)/total fat content in sample x 100%

TABLE 3 Effect of preterm formula liquid milk on fat digestibility in mice

As can be seen from table 3, the fat digestibility of the preterm formula liquid milk with the added compounded vegetable oil was higher in the mouse digestion test compared to the full fat preterm formula liquid milk. The lowest fat digestibility of the liquid milk of the full fat preterm formula fully indicates that the liquid milk of the full fat preterm formula is not suitable for the preterm. The preterm formula in the high dose group had a higher digestibility during the early stages of digestion and the fat digestibility increased well with time. In contrast, however, the total digestibility of fat was not as good as in the medium dose addition group. Medium dose addition group the initial digestibility of the preterm formula liquid milk was not as good as in the high dose group, but over time the digestibility of the preterm formula liquid milk was progressively higher than in the high dose group. The digestibility of the preterm formula liquid milk in the medium dose group is therefore better. The effects obtained in example 2 and example 3 are similar to those of example 1.

2) Mouse T cell subsets and immune factor assay

120 mice, half male and half female, were randomly divided into 5 groups. The following formulated liquid milks, example 1, comparative example 2, comparative example 3, and comparative example 4 were fed, respectively.

After the experiment is started, 3 mice are randomly taken from each group on the 0 th day and the 28 th day, after ether anesthesia, the heart is subjected to blood sampling, EDTA (ethylene diamine tetraacetic acid) anticoagulation, 10 mu L of peripheral blood is sucked into an EP (EP) tube, 1 mu L of CD3-FITC, CD4-PE and CD8a-Per CP monoclonal antibodies are respectively added to the peripheral blood and dyed in a dark place for 30min, 2ml of erythrocyte lysate with the ratio of 1:10 is added to each sample, the mixture is uniformly mixed, and the mixture is stood at the room temperature for 10min and then centrifuged at 3000r/min for 5 min. The supernatant was carefully discarded, 2ml of PBS buffer pH 7.4 was added, the mixture was washed 2 times, the supernatant was discarded, 400. mu.L of PBS buffer was added and mixed, and the number of CD3+ T, CD4+ T, CD8+ T cells was measured on a flow cytometer within 1 hour.

TABLE 4 Effect of preterm formula liquid milk on mouse T cell subpopulations

As can be seen from table 4, in example 1, comparative examples 1,2 and 3, T lymphocyte CD3+ showed significant difference (p <0.05), T lymphocyte CD4+ also showed significant difference (p <0.05) and T lymphocyte CD8+ showed no significant difference although it was increased compared with comparative example 4. T cells can participate in cellular immunity, so that the addition of nucleotides and lactoferrin is shown to improve the proliferation and growth of the T cells and improve the cellular immunity. The effects obtained in example 2 and example 3 are similar to those of example 1.

3) Diving platform experiment

40 male Kunming mice were randomly divided into 5 groups. The following formulated liquid milks, example 1, comparative example 2, comparative example 3, and comparative example 4 were fed, respectively.

The study and memory ability of each group of mice is tested by adopting a diving platform method, and the test is carried out in a quiet environment. The mouse diving tower instrument is divided into 2 rooms by a black plastic plate, a copper grid capable of being electrified is paved on the bottom surface of the mouse diving tower instrument, and a rubber platform with the length, width and height of 5cm is arranged in each room and is used as a safety area for avoiding electric shock of animals. During the experiment, the animal is firstly put into the reaction box to adapt for 3min, then the power is immediately switched on, the animal is shocked by electricity, and the escape reaction is that the animal jumps to the rubber table. At the moment, the electric stimulation is turned off, the mouse jumps to the copper grid for multiple times due to the fact that the mouse feels unsafe, when the four limbs of the mouse fall on the copper grid, the electric stimulation is turned on, the mouse jumps back to the platform quickly after receiving the electric shock, and the training is carried out for 5 min. After 24 hours, under the condition that a copper grid at the bottom is electrified, the mouse is directly and lightly placed on the platform, the time from the time when the mouse is placed on the rubber table to the time when the mouse jumps down for the first time is recorded, the latency period (LT) is called, the mouse can jump on the rubber table in an evasive way after being shocked, the number (n) of times when the mouse jumps down within 5min is recorded, and the LT and n are jointly used as the learning and memory achievement of the mouse.

Table 5 achievement of kunming mice in the diving platform experiment (n ═ 8)

Group number	Incubation period	Number of times of jumping from one platform to another
			Example 1	172.54±116.57	1.22±0.93
Comparative example 1	170.37±143.21	1.41±0.71
			Comparative example 2	171.24±119.74	1.31±0.99
Comparative example 3	171.78±121.14	1.35±0.77
			Comparative example 4	184.26±118.64	0.76±0.92

As shown in Table 5, the latency period and the number of jumping from the platform were not significantly different (p >0.01) in the case of example 1 and the cases of comparative examples 1,2 and 3 compared with the case of comparative example 4, but it was found that the cases of example 1 and the cases of comparative examples 1,2 and 3 compared with the case of comparative example 4 were increased, indicating that taurine promotes the development of the cerebral nerves and improves the learning and memory ability of the mice.

The effects obtained in example 2 and example 3 are similar to those of example 1.

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (10)

1. The formula liquid milk for the premature infant is characterized by comprising the following raw materials by volume: the mass concentration of raw milk is 62-115g/L, the mass concentration of skim milk is 62-65g/L, the mass concentration of compound vegetable oil is 11.6-28.8g/L, the mass concentration of whey protein powder is 6.5-7.5g/L, the mass concentration of desalted whey powder is 91-100g/L, the mass concentration of lactose is 22.5-58.5g/L, the mass concentration of glucose polymer is 2.5-6.5g/L, the mass concentration of compound vitamin is 0.25-0.5g/L, the mass concentration of compound mineral is 0.2-0.5g/L, the mass concentration of nucleotide is 0.05-0.09g/L, the mass concentration of taurine is 0.4-0.5mg/L, the mass concentration of lactoferrin is 0.05-0.13g/L, the mass concentration of animal bifidobacterium Bb-12 is 1800 white matter/L, the mass concentration of the food additive is 0.95-1.02 g/L.

2. The preterm infant formula liquid milk according to claim 1, wherein the compounded vegetable oil is composed of soybean oil, corn oil, low erucic acid rapeseed oil, coconut oil and high oleic acid sunflower seed oil, and the mass ratio of the soybean oil, the corn oil, the low erucic acid rapeseed oil, the coconut oil and the high oleic acid sunflower seed oil is 5:37:23:19: 15.

3. The premature infant formula liquid milk of claim 1, wherein the vitamin complex is composed of vitamin A, vitamin D, vitamin K, vitamin E, vitamin B1, vitamin B2, vitamin B6, vitamin B12, nicotinamide, folic acid, pantothenic acid, vitamin C, biotin and choline, and the mass ratio of the vitamin A, the vitamin D, the vitamin K, the vitamin E, the vitamin B1, the vitamin B2, the vitamin B6, the vitamin B12, the nicotinamide, folic acid, pantothenic acid, vitamin C, biotin and choline is 31:0.57:0.9:370:12.6:18.7:9.6:0.017:102.5:3.55:69:1630: 3429.

4. The premature infant formula liquid milk according to claim 1, wherein the compound minerals are composed of sodium, potassium, copper, magnesium, iron, zinc, manganese, calcium, phosphorus, iodine, chlorine and selenium, and the mass ratio of the sodium, potassium, copper, magnesium, iron, zinc, manganese, calcium, phosphorus, iodine, chlorine and selenium is 3841:8213:5.71:859:114:111:0.43:7430:4290:1.86:82130: 0.17.

5. The preterm infant formula liquid milk according to claim 1, wherein the food additive comprises 0.5-0.52g/L of soybean lecithin, 0.45-0.5g/L of monoglyceride/diglyceride fatty acid ester, 1-1.5mg/L of calcium carbonate and 0.05-0.1 mg/L of calcium monohydrogen phosphate by mass based on the volume of the prepared liquid milk.

6. The preterm infant formula liquid milk according to any one of claims 1 to 5, wherein the ratio of the total mass of whey protein to the total mass of casein in raw milk and skim milk is (5-6): 1.

7. the method of preparing preterm formula liquid milk of claim 6, comprising the steps of:

(1) filtering raw milk;

(2) mixing and dissolving the raw milk, the skim milk, the whey protein powder, the desalted whey powder, the lactose, the glucose polymer, the compound mineral, the nucleotide, the taurine, the lactoferrin, the bifidobacterium animalis Bb-12, the calcium carbonate and the calcium monohydrogen phosphate in the food additive and water after the filtration in the step (1) to obtain a water-soluble ingredient solution;

(3) adding the compound vitamins, soybean lecithin and mono-diglycerol fatty acid ester in the food additive into the compound vegetable oil, and mixing and dissolving the mixture to obtain a fat-soluble ingredient solution;

(4) mixing the water-soluble ingredient solution in the step (2) and the fat-soluble ingredient solution in the step (3), and adding water to a constant volume to reach the final concentration of each component;

(5) homogenizing the solution with constant volume in the step (4) under high pressure;

(6) putting the material homogenized under high pressure in the step (5) into a glass container, and sealing;

(7) sterilizing the container filled with the materials in the step (6);

(8) and (5) cooling the sterilized product in the step (7) to obtain a finished product.

8. The method according to claim 7, wherein the filtration in step (1) is carried out using a 44 mesh double-layer gauze.

9. The method according to claim 7, wherein the high-pressure homogenization in step (5) is carried out at a pressure of 25 to 35 MPa.

10. The preparation method according to claim 7, wherein the sterilization conditions in the step (7) are 110-120 ℃ and 10-15 min.