Formula milk powder and mixing method thereof

Abstract

The invention provides formula milk powder and a mixing method thereof. The mixing method comprises the following steps: mixing dry-mixed base powder with DHA (docosahexaenoic acid) to obtain formula milk powder, wherein the ratio of the specific surface area of the DHA to the specific surface area of the dry-mixed base powder is (0.8-2.5): 1, and the ratio of the mass of the DHA to the mass of the dry-mixed base powder is (2-7): 1000. The problem that dry-mixed base powder and DHA are difficult to uniformly mix when formula milk powder is prepared in the prior art can be solved, and the method is suitable for the field of milk powder preparation methods.

Description

Technical Field

[0001] The invention relates to the field of milk powder preparation methods, in particular to a formula milk powder and a mixing method thereof. Background Art

[0002] Formula milk powder is a scientifically designed infant food that is designed to simulate the nutritional components of breast milk and meet the growth and development needs of infants. It is usually based on skim milk powder, whole milk powder or other dairy products, with appropriate amounts of vitamins, minerals and essential fatty acids, such as DHA, added to provide comprehensive nutrition for infants. The production process of formula milk powder requires precise mixing of base powder and various nutrients during the production process to ensure the nutritional value and safety of the final product.

[0003] However, although the prior art can mix the dry-mixed base powder and heat-sensitive nutrients such as DHA to a certain extent to obtain formula milk powder by adjusting parameters such as premixing time, premixing paddle speed, dry mixing time and dry mixing paddle speed, it still faces the challenge of achieving uniform mixing. Although these parameters are considered to be the main factors affecting the uniformity of dry mixing, in actual operation, due to the limitations of various material properties and equipment performance, it is difficult to achieve the ideal mixing effect even after fine adjustment. This leads to uneven distribution of nutrients in the products obtained from the same batch of mixing. After such uneven products are packaged, the content of nutrients in different packages varies greatly, which in turn affects the overall quality of the formula milk powder and the health experience of consumers. Therefore, exploring more effective mixing technologies to overcome the limitations of the prior art and achieve higher quality uniform mixing is a technical problem that needs to be solved urgently in the formula milk powder industry. Summary of the invention

[0004] The main purpose of the present invention is to provide a formula milk powder and a mixing method thereof, so as to solve the problem in the prior art that dry-mixed base powder and DHA are difficult to mix uniformly when preparing formula milk powder.

[0005] In order to achieve the above-mentioned purpose, according to the first aspect of the present invention, a mixing method of formula milk powder is provided, the mixing method comprising: mixing a dry mixed base powder with DHA to obtain formula milk powder; wherein the ratio of the specific surface area of ​​DHA to the specific surface area of ​​the dry mixed base powder is 0.8-2.5:1, and the ratio of the mass of DHA to the mass of the dry mixed base powder is 2-7:1000.

[0006] Furthermore, the ratio of the specific surface area of ​​DHA to the specific surface area of ​​the dry mixed base powder is 1.5-2.0:1; preferably, the ratio of the mass of DHA to the mass of the dry mixed base powder is 3-4:1000; preferably, the specific surface area of ​​DHA is 40-125m 2 / kg; preferably, the specific surface area of ​​the dry mixed base powder is 45-55m 2 / kg, more preferably 50m 2 / kg.

[0007] Furthermore, mixing includes premixing and dry mixing performed in sequence, wherein premixing includes: placing the dry mixed base powder and DHA in the same container, performing preliminary mixing, and obtaining a premixed material; dry mixing includes: further mixing the premixed material to obtain formula milk powder; preferably, before premixing, the dry mixed base powder, DHA and heat-sensitive materials are placed in the same container, and then premixed to obtain a premixed material; the heat-sensitive material includes one or more of probiotics, ARA, lactoferrin or nucleotides.

[0008] Furthermore, the premixing time is 50-70 seconds, and the rotation speed of the stirring paddle used for premixing is 14-34 rpm.

[0009] Furthermore, the dry mixing time is 100-140 s, and the rotation speed of the stirring paddle used for dry mixing is 60-80 rpm.

[0010] Furthermore, the dry mixed base powder includes: 366-427 parts of raw milk dry powder, 200-250 parts of desalted whey powder, 200-250 parts of skimmed milk powder, 80-100 parts of galacto-oligosaccharide, 50-80 parts of 1,3-dioleoyl-2-palmitoylglycerol, 1-4 parts of concentrated whey protein powder, 7-12 parts of xylitol, 7-17 parts of calcium carbonate, 4-7 parts of milk mineral salts, 1-3 parts of compound vitamins, 0.5-2 parts of compound minerals, 0.5-2 parts of compound nutrients, 1-3 parts of arachidonic acid oil powder and 2-4 parts of docosahexaenoic acid oil powder.

[0011] Furthermore, the compound vitamins include, by mass percentage: 0.6% to 0.9% retinyl acetate, 0.8% to 1.1% cholecalciferol, 3.5% to 5.2% DL-α-tocopherol acetate, 0.3% to 0.4% phytonadione, 0.2% to 0.3% thiamine nitrate, 0.03% to 0.12% riboflavin, 0.08% to 0.12% pyridoxine hydrochloride, and 0.4% to 0.5% cyanocobalamin. , niacinamide 0.4% ~ 0.7%, folic acid 0.2% ~ 0.4%, D-calcium pantothenate 0.4% ~ 0.6%, L-sodium ascorbate 15% ~ 24%, biotin 0.3% ~ 0.5%, lutein 0.5% ~ 1.1%, inositol 3.1% ~ 4.0%, L-carnitine 1.5% ~ 1.9%, choline 32% ~ 44% and lactose as a carrier of complex vitamins 14.2% ~ 35.73%.

[0012] Furthermore, in terms of mass percentage, the complex minerals include: 0.08% to 0.14% copper sulfate, 0.5% to 7.5% magnesium sulfate, 1.2% to 2.4% ferrous sulfate, 0.7% to 1.2% zinc sulfate, 0.008% to 0.015% manganese sulfate, 0.3% to 0.8% potassium iodate, 0.4% to 0.7% sodium selenite, 42% to 81% calcium citrate, 6% to 23% sodium citrate, 8% to 15% potassium chloride, and 1 to 34.51% lactose as a carrier of the complex minerals; preferably, in terms of mass percentage, the complex nutrients include: 0.5% to 1.1% lutein, 3.1% to 4.0% inositol, 1.5% to 1.9% L-carnitine, 42% to 54% choline, and 40.20% to 51.73% lactose as a carrier of the complex nutrients.

[0013] Furthermore, the preparation method of the dry mixed base powder includes: sterilizing the raw milk, mixing and homogenizing with nutrients to obtain a mixed liquid; evaporating the water in the mixed liquid to obtain concentrated milk; and preheating and spray-drying the concentrated milk in sequence to obtain the dry mixed base powder.

[0014] To achieve the above object, according to a second aspect of the present invention, a formula milk powder is provided. The formula milk powder is prepared by the mixing method of the above formula milk powder, and the relative standard deviation of DHA content between different positions in the formula milk powder is ≤10%.

[0015] By applying the technical solution of the present invention, by controlling the ratio of the specific surface areas of the dry-mixed base powder and DHA during dry mixing, the dry-mixed base powder and DHA can be uniformly mixed during dry mixing to obtain a formula milk powder, in which the relative standard deviation of the DHA content between different parts (different positions) in the formula milk powder is ≤10%. DETAILED DESCRIPTION

[0016] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0017] Terminology explanation:

[0018] Specific surface area: the total surface area of ​​powder particles per unit mass, in m 2 / kg.

[0019] As mentioned in the background art, in the prior art, in the dry mixing step of milk powder, the uniform mixing of heat-sensitive nutrients such as DHA in the dry mixed base powder is usually controlled by adjusting parameters such as premixing time, premixing paddle speed, dry mixing time, and dry mixing paddle speed. However, in actual production, it is difficult to achieve more uniform mixing by only adjusting the above parameters. Therefore, in this application, the inventors tried to develop a new mixing method and proposed a series of protection schemes of this application.

[0020] In a first typical embodiment of the present application, a mixing method for formula milk powder is provided, characterized in that the mixing method comprises: mixing a dry mixed base powder with DHA to obtain formula milk powder; wherein the ratio of the specific surface area of ​​DHA to the specific surface area of ​​the dry mixed base powder is 0.8-2.5:1, and the ratio of the mass of DHA to the mass of the dry mixed base powder is 2-7:1000.

[0021] In the preparation of formula milk powder, for heat-sensitive materials such as DHA that are easily decomposed and deteriorated by heat, a dry mixing method is usually used to mix them with a dry mixed base powder to finally obtain formula milk powder. In daily actual production practice, the inventor accidentally discovered that the ratio of the specific surface area of ​​the dry mixed base powder and DHA will affect the uniformity of dry mixing. Therefore, in the mixing method of the present application, by controlling the specific surface area of ​​the dry mixed base powder and DHA, the ratio of the specific surface area of ​​DHA to the specific surface area of ​​the dry mixed base powder is controlled at 0.8-2.5:1, and the mass ratio of DHA to the dry mixed base powder is controlled at 2-7:1000, and then mixing is performed, which can improve the uniformity of dry mixing and obtain a uniformly mixed formula milk powder.

[0022] Preferably, multiple sampling is performed at different positions in the above formula milk powder, and the DHA content in the sampled samples is tested respectively. The relative standard deviation (RSD) of the DHA content is ≤10% (the number of samples sampled is ≥12), which means that the DHA in the formula milk powder is uniformly mixed.

[0023] In a preferred embodiment, the ratio of the specific surface area of ​​DHA to the specific surface area of ​​the dry mixed base powder is 1.5-2.0:1.

[0024] More preferably, in order to further improve the uniform distribution of DHA in the formula milk powder, the ratio of the specific surface areas of the materials is controlled before dry mixing, and the ratio of the specific surface area of ​​DHA to the specific surface area of ​​the dry mixed base powder is controlled at 1.5-2.0:1, including but not limited to 1.5:1, 1.55:1, 1.6:1, 1.65:1, 1.7:1, 1.75:1, 1.8:1, 1.85:1, 1.9:1, 1.95:1, and 2.0:1, which can further ensure the uniform distribution of DHA in the formula milk powder and obtain a uniformly mixed formula milk powder.

[0025] The ratio of the mass of DHA to the mass of the dry mixed base powder is 2-7:1000, including but not limited to 2:1000, 2.5:1000, 3:1000, 3.5:1000, 4:1000, 4.5:1000, 5:1000, 5.5:1000, 6:1000, 6.5:1000 or 7:1000. In a preferred embodiment, the ratio of the mass of DHA to the mass of the dry mixed base powder is 3-4:1000.

[0026] In a preferred embodiment, the specific surface area of ​​DHA is 40-125 m 2 / kg, including but not limited to 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, 115, 120 or 125 m 2 / kg.

[0027] In a preferred embodiment, the specific surface area of ​​the dry mixed base powder is 45-55m 2 / kg, including but not limited to 45, 46, 47, 48, 49, 50, 51, 52, 53, 54 or 55m 2 / kg; more preferably 50m 2 / kg. In actual production applications, the specific surface area of ​​dry-mixed base powder does not change much, and is between 45-55m 2 In the above mixing method, the specific surface area of ​​DHA is mainly controlled to achieve uniform mixing of DHA in formula milk powder.

[0028] In a preferred embodiment, mixing includes premixing and dry mixing performed in sequence, wherein premixing includes: placing the dry mixed base powder and DHA in the same container, performing preliminary mixing, and obtaining a premixed material; dry mixing includes: further mixing the premixed material to obtain a formula milk powder; preferably, before premixing, placing the dry mixed base powder, DHA and a heat-sensitive material in the same container, and then premixing to obtain a premixed material; the heat-sensitive material includes one or more of probiotics, ARA, lactoferrin or nucleotides.

[0029] In the above-mentioned mixing, the dry-mixed base powder and DHA are first premixed in a premixer, i.e., preliminarily mixed to obtain a premixed material, and then the premixed material is transferred to a dry mixer for dry mixing (i.e., the above-mentioned further mixing) to obtain a mixed product formula milk powder. The dry-mixed base powder is a mixture of milk powder, auxiliary materials, and nutrients that are stable at high temperatures. In the above-mentioned mixing process, the raw materials are not limited to the dry-mixed base powder and DHA, and other heat-sensitive materials (including but not limited to one or more of probiotics, ARA, lactoferrin or nucleotides) can also be mixed with the dry-mixed base powder according to actual needs to obtain a more nutritious formula milk powder.

[0030] Preferably, the probiotics include but are not limited to Bifidobacterium animalis.

[0031] In a preferred embodiment, the premixing time is 50-70 s, preferably 55-65 s, more preferably 60 s.

[0032] In a preferred embodiment, the rotation speed of the stirring paddle used for premixing is 14-34 rpm, preferably 19-29 rpm, and more preferably 24 rpm.

[0033] In the premixing, the premixing time includes but is not limited to 50, 52.5, 55, 57.5, 60, 62.5, 65, 67.5 or 70 s, and the speed of the stirring paddle used for premixing includes but is not limited to 19, 20, 21, 22, 23, 24, 25, 26, 27, 28 or 29 rpm.

[0034] In a preferred embodiment, the dry mixing time is 100-140 s, preferably 110-130 s, and more preferably 120 s.

[0035] In a preferred embodiment, the rotation speed of the stirring paddle used for dry mixing is 60-80 rpm, preferably 65-75 rpm, and more preferably 69.3 rpm.

[0036] In dry mixing, the dry mixing time includes but is not limited to 100, 105, 110, 115, 120, 125, 130, 135 or 140s, and the speed of the stirring paddle used for premixing includes but is not limited to 60, 62.5, 65, 67.5, 70, 72.5, 75, 77.5 or 80rpm.

[0037] By using the above parameters of premixing and dry mixing, the dry mixed base powder and DHA can be uniformly mixed in the above mixing method. In the above premixing and dry mixing, the same agitator is used, and the above mixing can be achieved by performing premixing and dry mixing in the same device.

[0038] In a preferred embodiment, the dry mixed base powder includes: 366-427 parts of raw milk dry powder, 200-250 parts of desalted whey powder, 200-250 parts of skimmed milk powder, 80-100 parts of galacto-oligosaccharide, 50-80 parts of 1,3-dioleyl-2-palmitoylglycerol triester, 1-4 parts of concentrated whey protein powder, 7-12 parts of xylitol, 7-17 parts of calcium carbonate, 4-7 parts of milk mineral salts, 1-3 parts of compound vitamins, 0.5-2 parts of compound minerals, 0.5-2 parts of compound nutrients, 1-3 parts of arachidonic acid oil powder and 2-4 parts of docosahexaenoic acid oil powder.

[0039] The above-mentioned dry mixed base powder contains milk powder, auxiliary materials and nutrients that are stable under high temperature conditions. The raw milk dry powder in the above-mentioned dry mixed base powder is the product of drying raw milk, that is, the dry matter in raw milk. The preparation method of the above-mentioned dry mixed base powder includes but is not limited to: mixing liquid raw milk with other components of the dry mixed base powder, and then drying to obtain a dry powdered dry mixed base powder. For the convenience of measurement, in the above-mentioned dry mixed base powder, the raw milk dry powder (that is, the dry matter in raw milk) is measured. This measurement method does not affect and limit the preparation method of the dry mixed base powder. Preferably, the dry matter content in the liquid raw milk is 12.0%-12.5%.

[0040] In the prior art, for this type of formula milk powder, a mixing method similar to that of the present application is mostly used, that is, auxiliary materials and nutritional ingredients that are stable under high temperature conditions are mixed with an emulsion and then dried to obtain a dry mixed base powder, and then the dry mixed base powder is dry mixed with heat-sensitive ingredients to prevent high temperature from destroying the heat-sensitive ingredients, and finally a nutritious formula milk powder is obtained. Those skilled in the art can flexibly adjust the ingredients and proportions in the dry mixed base powder according to the actual needs of the formula milk powder.

[0041] In a preferred embodiment, the compound vitamins include, by mass percentage: 0.6% to 0.9% retinyl acetate, 0.8% to 1.1% cholecalciferol, 3.5% to 5.2% DL-α-tocopherol acetate, 0.3% to 0.4% phytonadione, 0.2% to 0.3% thiamine nitrate, 0.03% to 0.12% riboflavin, 0.08% to 0.12% pyridoxine hydrochloride, 0.4% to 0.06% cyanocobalamin. .5%, niacinamide 0.4% ~ 0.7%, folic acid 0.2% ~ 0.4%, D-calcium pantothenate 0.4% ~ 0.6%, L-sodium ascorbate 15% ~ 24%, biotin 0.3% ~ 0.5%, lutein 0.5% ~ 1.1%, inositol 3.1% ~ 4.0%, L-carnitine 1.5% ~ 1.9%, choline 32% ~ 44% and lactose as a carrier of complex vitamins 14.2% ~ 35.73%.

[0042] In a preferred embodiment, the complex minerals include, by mass percentage, 0.08% to 0.14% copper sulfate, 0.5% to 7.5% magnesium sulfate, 1.2% to 2.4% ferrous sulfate, 0.7% to 1.2% zinc sulfate, 0.008% to 0.015% manganese sulfate, 0.3% to 0.8% potassium iodate, 0.4% to 0.7% sodium selenite, 42% to 81% calcium citrate, 6% to 23% sodium citrate, 8% to 15% potassium chloride, and 1 to 34.51% lactose as a carrier of the complex minerals.

[0043] In a preferred embodiment, the compound nutrients include, by mass percentage, 0.5% to 1.1% lutein, 3.1% to 4.0% inositol, 1.5% to 1.9% L-carnitine, 42% to 54% choline, and 40.20% to 51.73% lactose as a carrier of the compound nutrients.

[0044] In a preferred embodiment, the preparation method of the dry mixed base powder includes: sterilizing raw milk, mixing and homogenizing with nutrients to obtain a mixed liquid; evaporating water in the mixed liquid to obtain concentrated milk; and preheating and spray drying the concentrated milk in sequence to obtain a dry mixed base powder.

[0045] Preferably, in the present application, the preparation method of the dry mixed base powder is as follows, and those skilled in the art can also flexibly adjust it according to actual production.

[0046] 1. Fresh milk reception and sterilization: After the raw milk arrives at the factory, it is sampled and tested. After passing the test, it is cooled and pumped into a storage tank through the milk collection pipeline for temporary storage. After the milk is purified, it is heated and sterilized through a plate heat exchanger. After sterilization and cooling, it is pumped into a storage tank for temporary storage.

[0047] 2. Mixing: According to the production formula, pasteurized milk and RO water are pumped into the circulating mixing system composed of a wet mixing tank and a vacuum mixer. When the mixing temperature reaches 50°C, the vacuum mixer absorbs the raw and auxiliary materials in the powder bin through negative pressure. After the system circulates the mixing, it is temporarily stored in the wet mixing tank.

[0048] 3. Homogenization and wet mixing storage: The edible vegetable blending oil and the wet mixed liquid are heated up in the static mixer and then enter the homogenizer for homogenization. After homogenization, the liquid is cooled down and enters the wet mixing storage tank for temporary storage.

[0049] 4. Water evaporation: The mixed liquid is pumped from the mixing storage tank into the evaporator balance tank, then enters the preheater for preheating, enters the top of the flash evaporator for heating, and then enters the heater and insulation pipe for sterilization. The sterilized material enters the lower part of the flash evaporator for cooling, and then enters the effect body for concentration. The effect body is steam heated by a hot pressure pump. The material is evaporated and concentrated in the first, second and third effect bodies (i.e. the first evaporator, the second evaporator and the third evaporator) and enters the concentrated milk tank.

[0050] 5. Preheating of concentrated milk: The concentrated milk is heated by a tubular heat exchanger and then enters the atomizing spray gun.

[0051] 6. Atomization and agglomeration: After concentration, the material is atomized at high pressure, and the droplets come into contact with hot air and dry instantly. The fine powder particles brought out by the exhaust of the drying tower enter the top of the drying tower through the backflush pipe and undergo dry-wet agglomeration with the concentrated milk droplets. The droplets and powder particles adhere together to increase the diameter of the powder particles.

[0052] 7. Static bed agglomeration and cooling: The powder particles of concentrated milk droplets after instant drying by hot air fall into the static bed at the bottom of the drying tower, and are cooled by 60-68℃ hot air. The powder particles are dry-dry agglomerated to increase the diameter of the powder particles.

[0053] 8. Fluidized bed agglomeration cooling: The milk powder enters the next process after being cooled by clean air.

[0054] 9. Negative pressure dense phase conveying: The dried and cooled milk powder is transported and stored in the silo through pipeline negative pressure dense phase conveying, which reduces the damage of powder particles during the transportation process.

[0055] 10. Dry mixing: Use a double-blade dry mixer to evenly mix the wet semi-finished product and the dry mixed raw material DHA to achieve a relative standard deviation of dry mixed nutrients ≤10%, wherein the key points are premixing time 50-70s, dry mixing time 100-140s, the speed of the stirring paddle used for premixing 14-34rpm, the speed of the stirring paddle used for dry mixing 60-80rpm, the specific surface area ratio of DHA to the specific surface area of ​​the dry mixed base powder is controlled in the range of 0.8-2.5, preferably 1.5-2.0, which can ensure that the relative standard deviation of the uniformity of dry mixed DHA is ≤10%.

[0056] 11. Packaging: Vacuum powder filling technology and mixed gas (carbon dioxide and nitrogen) pre-filling system are used to can milk powder in a mixed gas environment.

[0057] In a second typical embodiment of the present application, a formula milk powder is provided. The formula milk powder is prepared by the mixing method of the formula milk powder described above, and the relative standard deviation of the DHA content between different positions in the formula milk powder is ≤10%.

[0058] More preferably, the relative standard deviation of the DHA content in the formula milk powder includes but is not limited to ≤9%, ≤8.5%, ≤8%, ≤7.5%,

[0059] ≤7%, ≤6.5%, ≤6%, ≤5.5%, ≤5%, ≤4.5%, ≤4%, ≤3.5%, ≤3.2%, ≤3% or ≤2.7%.

[0060] The formula milk powder prepared by the above mixing method was sampled at different positions of the formula milk powder prepared in the same batch, and the relative standard deviation of the DHA content in the samples was ≤10%.

[0061] The beneficial effects of the present application will be further explained in detail below in conjunction with specific embodiments.

[0062] Example 1

[0063] 1. Premix and dry mix

[0064] The experiment used the same supplier, different specific surface areas as dry mixed raw materials DHA and specific surface areas of 45-55m 2 / kg infant formula milk powder (i.e. dry mixed base powder, Feifan infant formula milk powder (not containing DHA) used in this embodiment) was used as the experimental material for dry mixing uniformity verification. The data of the particle size of DHA, the specific surface area of ​​the dry mixed base powder and the specific surface area ratio used in Experimental Examples 1-6 and Comparative Examples 1-4 are shown in Table 1.

[0065] The experimental premixing equipment was a single-paddle premixer, and the dry mixing equipment was a double-paddle dry mixer. The amount of DHA added in each experiment was 2.5 kg, the amount of dry mixed base powder added was 997.5 kg, the premixing time was 60 s, the premixer agitator speed was 24 rpm, the dry mixing time was 120 s, and the dry mixer agitator speed was 69.3 rpm.

[0066] The specific surface area results in this application were all obtained using a Malvern particle size analyzer Mastersizer 3000.

[0067] Table 1

[0068]

[0069] 2. Sampling process:

[0070] After dry mixing, samples were evenly distributed from the front to the back of the packaging process. A total of 12 samples were taken and sent to the laboratory for testing of DHA content.

[0071] 3. Evaluation methods and standards for dry mixing uniformity:

[0072] 1. Mixing uniformity qualification evaluation standard: relative standard deviation (RSD) ≤ 10%.

[0073] 2. Relative standard deviation calculation formula:

[0074]

[0075] 4. The experimental results are shown in Table 2:

[0076] Table 2

[0077]

[0078] V. Conclusion:

[0079] The specific surface area ratio of DHA to the specific surface area of ​​the dry-mixed base powder is controlled in the range of 0.8-2.5:1, which can ensure that the relative standard deviation of the dry-mixed DHA is ≤10%, and more preferably, when it is 1.5-2.0:1, the relative standard deviation of the dry-mixed DHA is ≤4%, which can ensure that the distribution of DHA after dry mixing is more uniform.

[0080] Example 2

[0081] The sources of DHA and dry mixed base powder are the same as those in Example 1, and the specific surface area of ​​DHA is 100m 2 / kg, the specific surface area of ​​dry mixed base powder is 50m 2 / kg, the specific surface area ratio (DHA specific surface area ÷ dry mixed base powder specific surface area) is 2. The difference between the experiments lies in the mass ratio of DHA to dry mixed base powder.

[0082] The mixing method is the same as in Example 1. The experimental premixing equipment is a single-blade premixer, and the dry mixing equipment is a double-blade dry mixer. The amount of DHA added and the amount of dry mixed base powder added in each test are shown in Table 3. The premixing time is 60s, the premixer stirring paddle speed is 24rpm, the dry mixing time is 120s, and the dry mixer stirring paddle speed is 69.3rpm.

[0083] The sampling process, dry mixing uniformity evaluation method and standard are the same as those in Example 1.

[0084] The test parameters and results are shown in Table 3.

[0085] Table 3

[0086]

[0087] The mass ratio of DHA to dry mixed base powder is controlled in the range of 2-7:1000, which can ensure that the relative standard deviation of dry mixed DHA is ≤10%, and more preferably, when it is 3-4:1000, the relative standard deviation of dry mixed DHA is ≤3%, which can ensure that the distribution of DHA after dry mixing is more uniform.

[0088] Example 3

[0089] Select 1000kg and specific surface area of ​​50m 2 / kg dry mixed base powder was used to carry out the experiments of Comparative Examples 11-14, the specific surface area and addition amount of DHA were adjusted, and the mixing method was the same as that of Example 1. The sampling process, dry mixing uniformity evaluation method and standard were the same as those of Example 1.

[0090] The test parameters and results are shown in Table 4. The RSDs of Comparative Examples 11-14 all failed to meet the requirements, and the DHA was unevenly distributed in the dry-mixed base powder after dry-mixing.

[0091] Table 4

[0092]

[0093] From the above description, it can be seen that the above-mentioned embodiments of the present invention achieve the following technical effects: in the above-mentioned mixing method, by controlling the specific surface area of ​​the dry mixed base powder and DHA to 0.8-2.5:1, and the ratio of the mass of DHA to the mass of the dry mixed base powder to 2-7:1000, the dry mixed base powder and DHA can be uniformly mixed to obtain a formula milk powder with a relative standard deviation of DHA ≤10%.

[0094] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for mixing formula milk powder, characterized in that: The hybrid method includes: Mixing the dry mixed base powder with DHA to obtain the formula milk powder; Wherein, the ratio of the specific surface area of ​​the DHA to the specific surface area of ​​the dry mixed base powder is 0.8-2.5:1; The ratio of the mass of the DHA to the mass of the dry mixed base powder is 2-7:1000.

2. The mixing method according to claim 1, characterized in that The ratio of the specific surface area of ​​the DHA to the specific surface area of ​​the dry mixed base powder is 1.5-2.0:1; Preferably, the ratio of the mass of the DHA to the mass of the dry mixed base powder is 3-4:1000; Preferably, the specific surface area of ​​the DHA is 40-125 m 2 / kg; Preferably, the specific surface area of ​​the dry mixed base powder is 45-55m 2 / kg.

3. The mixing method according to claim 1 or 2, characterized in that: The mixing includes premixing and dry mixing performed sequentially, The premixing comprises: placing the dry mixed base powder and the DHA in the same container, performing preliminary mixing to obtain a premixed material; The dry mixing includes: further mixing the premixed materials to obtain the formula milk powder; Preferably, before the premixing, the dry mixed base powder, the DHA and the heat-sensitive material are placed in the same container, and then the premixing is performed to obtain the premixed material; The heat-sensitive material includes one or more of probiotics, ARA, lactoferrin or nucleotides.

4. The mixing method according to claim 3, characterized in that The premixing time is 50-70s, and the rotation speed of the stirring paddle used for the premixing is 14-34rpm.

5. The mixing method according to claim 3, characterized in that The dry mixing time is 100-140s, and the rotation speed of the stirring paddle used for the dry mixing is 60-80rpm.

6. The mixing method according to any one of claims 1 to 5, characterized in that The dry mixed base powder comprises: 366-427 parts of raw milk dry powder, 200-250 parts of desalted whey powder, 200-250 parts of skimmed milk powder, 80-100 parts of galacto-oligosaccharide, 50-80 parts of 1,3-dioleoyl-2-palmitoylglycerol triester, 1-4 parts of concentrated whey protein powder, 7-12 parts of xylitol, 7-17 parts of calcium carbonate, 4-7 parts of milk mineral salts, 1-3 parts of complex vitamins, 0.5-2 parts of complex minerals, 0.5-2 parts of complex nutrients, 1-3 parts of arachidonic acid oil powder and 2-4 parts of docosahexaenoic acid oil powder.

7. The mixing method according to claim 6, characterized in that In terms of mass percentage, the compound vitamins include: 0.6% to 0.9% retinyl acetate, 0.8% to 1.1% cholecalciferol, 3.5% to 5.2% DL-α-tocopherol acetate, 0.3% to 0.4% phytonadione, 0.2% to 0.3% thiamine nitrate, 0.03% to 0.12% riboflavin, 0.08% to 0.12% pyridoxine hydrochloride, 0.4% to 0.5% cyanocobalamin, nicotinic acid The invention discloses a compound vitamin comprising 0.4% to 0.7% chrysanthemum amine, 0.2% to 0.4% folic acid, 0.4% to 0.6% D-calcium pantothenate, 15% to 24% L-sodium ascorbate, 0.3% to 0.5% biotin, 0.5% to 1.1% lutein, 3.1% to 4.0% inositol, 1.5% to 1.9% L-carnitine, 32% to 44% choline and 14.2% to 35.73% lactose as a carrier of the compound vitamins.

8. The mixing method according to claim 6, characterized in that In terms of mass percentage, the composite minerals include: 0.08% to 0.14% copper sulfate, 0.5% to 7.5% magnesium sulfate, 1.2% to 2.4% ferrous sulfate, 0.7% to 1.2% zinc sulfate, 0.008% to 0.015% manganese sulfate, 0.3% to 0.8% potassium iodate, 0.4% to 0.7% sodium selenite, 42% to 81% calcium citrate, 6% to 23% sodium citrate, 8% to 15% potassium chloride, and 1% to 34.51% lactose as a carrier of the composite minerals; Preferably, in terms of mass percentage, the compound nutrients include: 0.5% to 1.1% lutein, 3.1% to 4.0% inositol, 1.5% to 1.9% L-carnitine, 42% to 54% choline, and 40.20% to 51.73% lactose as a carrier of the compound nutrients.

9. The mixing method according to any one of claims 1 to 8, characterized in that The preparation method of the dry mixed base powder comprises: After sterilizing the raw milk, it is mixed and homogenized with the nutrients to obtain a mixed liquid; Evaporating the water in the mixed liquid to obtain concentrated milk; The concentrated milk is preheated and spray-dried in sequence to obtain the dry mixed base powder.

10. A formula milk powder, characterized in that: The formula milk powder is a formula milk powder prepared by the mixing method of formula milk powder according to any one of claims 1 to 9, Preferably, the relative standard deviation of the DHA content at different locations within the formula milk powder is ≤10%.

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