Deep hypothermia breast milk freeze-dried powder as well as preparation method and application thereof

Abstract

The invention discloses deep hypothermia breast milk freeze-dried powder as well as a preparation method and application thereof. The method comprises the following steps: collecting breast milk, freezing the breast milk at low temperature to prepare smoothie particles, freeze-drying, and grinding to obtain the deep hypothermia breast milk freeze-dried powder. After the breast milk is frozen at low temperature, the breast milk is prepared into smoothie particles, so that the freeze-drying efficiency is improved, the freeze-drying time is shortened, more active factors are reserved, and the storage life is prolonged.

Description

Technical Field

[0001] The invention belongs to the field of biotechnology and relates to deep-low temperature breast milk freeze-dried powder and a preparation method and application thereof. Background Art

[0002] Breast milk is the best food for feeding infants. It contains nutrients and bioactive substances that infants need for survival and healthy growth. The known nutrients in breast milk include three nutrients with high content, namely protein, fat and carbohydrates, and micronutrients with low content, such as minerals and vitamins. The content and proportion of each nutrient are moderate, easy to digest and absorb, and beneficial to the healthy growth and development of infants.

[0003] The protein in breast milk is not only of good quality but also of moderate proportion. The ratio of albumin to casein is about 7:3, of which casein is β-casein, which is not easy to coagulate and is easy for infants to digest and absorb. The fat in breast milk provides about half of the energy for infants. It also contains a variety of essential fatty acids, such as linoleic acid, arachidonic acid, docosahexaenoic acid, etc., which play an important role in the intelligence, vision and physical growth and development of infants. The carbohydrates in breast milk are mainly lactose, among which the highest content of beta-lactose is not only conducive to the growth of beneficial bacteria, but also makes them produce a large number of vitamins, promote intestinal peristalsis, help the small intestine absorb calcium, magnesium and amino acids, and help the development of the brain. The mineral content in breast milk is moderate, which plays an important role in the growth and development of infants. In addition, breast milk also contains a large number of bioactive substances, mainly immune factors, immunoglobulins, chemokines, growth factors, oligosaccharides, etc., which can not only promote the development of infants' intestinal and endocrine systems, but also have anti-infection and antioxidant effects.

[0004] The disposal of excess breast milk has become a research hotspot in recent years, mainly focusing on the development of breast milk storage, donation, processing and utilization and related technologies. The following are several main disposal methods: 1. Frozen storage, 2. Donation to breast milk banks, 3. Processing and utilization of breast milk.

[0005] Cryo-storage method: freeze and store excess breast milk for future use when the baby needs it. Studies have found that some immune components and fatty acids in breast milk will be reduced during the freezing process, so improving freezing and thawing technology to reduce nutritional losses is one of the main research directions.

[0006] Breast milk bank donation method: donate excess breast milk to a breast milk bank to help babies in need. Currently, many countries have established standardized breast milk bank systems for collecting, testing and distributing breast milk. Research focuses on how to ensure the safety of donated breast milk and improve the efficiency of breast milk bank management, including the optimization of sterilization technologies such as pasteurization.

[0007] Breast milk processing and utilization methods: Breast milk is processed into breast milk powder, breast milk fat supplements and other forms for use in infant formula and clinical purposes. Research on breast milk powder and other breast milk-derived products focuses on how to retain the key active ingredients in breast milk during processing. Technologies such as spray drying and freeze drying have been used to maximize the preservation of nutrients and bioactive substances in breast milk.

[0008] Patent CN101422240A discloses a production process of freeze-dried human breast milk (including colostrum) powder, its products and uses. It mentions that freeze-dried breast milk powder can be obtained by centrifugation to remove impurities, remove fat, pasteurize, and freeze-dry at low temperature. However, the freeze-drying process of this patent requires fat removal and pasteurization, which greatly reduces the nutritional value and biological activity.

[0009] Therefore, there is an urgent need to provide a freeze-drying method that effectively ensures the nutritional value and biological activity of breast milk. Summary of the invention

[0010] In view of the deficiencies in the prior art and actual needs, the present invention provides a deep-low temperature breast milk freeze-dried powder and a preparation method and application thereof, which solves the problems of the prior freeze-drying technology in insufficient surface area utilization of breast milk samples, slow water evaporation rate, long freeze-drying time, and damage to nutrients and bioactive substances in breast milk.

[0011] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0012] In a first aspect, the present invention provides a method for preparing deep-low temperature breast milk freeze-dried powder, the method comprising: collecting breast milk, freezing the breast milk at low temperature to make smoothie particles, freeze-drying the particles, and grinding the freeze-dried particles to obtain the deep-low temperature breast milk freeze-dried powder.

[0013] The invention processes breast milk through low-temperature freezing to prepare ice smoothie particles, thereby improving freeze-drying efficiency, reducing freeze-drying time, retaining more active factors, and extending the shelf life.

[0014] Preferably, the low-temperature freezing temperature is -40°C to -20°C (e.g., -40°C, -38°C, -35°C, -30°C, -25°C, -22°C, -21°C, -20°C), and the low-temperature freezing time is 1-5h (e.g., 1h, 2h, 3h, 4h, 5h).

[0015] Preferably, the diameter of the smoothie particles is 6-8 mm (eg, 6 mm, 7 mm, 8 mm).

[0016] Preferably, the freeze-drying comprises: performing freeze-drying using a freeze-drying machine with a support, wherein the support is connected to a tray.

[0017] Preferably, the number of the trays is 6 to 8 (eg, 6, 7, 8), and the diameter of the tray is 20 to 28 cm (eg, 20 cm, 25 cm, 28 cm).

[0018] Preferably, the height of the bracket is 3 to 5 cm (eg, 3 cm, 4 cm, 5 cm).

[0019] Preferably, the grinding speed is 1500-2000 r / min (eg, 1500 r / min, 1800 r / min, 2000 r / min), and the grinding time is 10-20 s (eg, 10 s, 15 s, 20 s).

[0020] Preferably, the method further comprises irradiating after grinding.

[0021] Preferably, the irradiation temperature is 2°C to 5°C (e.g., 2°C, 3°C, 4°C, 5°C), the irradiation dose is 8 to 10 kGy (e.g., 8 kGy, 9 kGy, 10 kGy), and the irradiation time is 5 to 15 min (e.g., 5 min, 8 min, 15 min).

[0022] In a second aspect, the present invention provides a deep-low temperature breast milk freeze-dried powder, which is prepared by the method described in the first aspect.

[0023] In a third aspect, the present invention provides a freeze-dried breast milk powder product, which contains the deep-temperature freeze-dried breast milk powder described in the second aspect, and the mass percentage of the deep-temperature freeze-dried breast milk powder in the freeze-dried breast milk powder product is 1 to 99% (for example, 1%, 2%, 3%, 10%, 50%, 90%, 99%).

[0024] In a fourth aspect, the present invention provides the use of the deep-low temperature breast milk freeze-dried powder described in the second aspect or the breast milk freeze-dried powder product described in the third aspect in the preparation of a product for preventing and / or treating immunodeficiency.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The low-temperature freezing treatment of breast milk samples by the method of the present invention can ensure the stability of the emulsion, which is beneficial to improving the freeze-drying efficiency, reducing the freeze-drying time, retaining more active factors, and extending the shelf life;

[0027] (2) After the frozen breast milk of the present invention is placed in an ice crusher for crushing, ice is formed into 6-8 mm sized smoothie particles, and then the smoothie particles are placed in a freeze dryer for precooling, thereby increasing the surface area of ​​the breast milk sample, facilitating the volatilization of water during the freeze drying process, shortening the freeze drying time, and increasing the content of active factors;

[0028] (3) The present invention places a support in the freeze-drying tray, and improves the surface area utilization rate of the sample by adjusting the height of the support, the number and diameter of the freeze-drying tray, accelerates the volatilization rate of water, can effectively shorten the freeze-drying time, and increase the content of active factors in breast milk. DETAILED DESCRIPTION

[0029] To further illustrate the technical means and effects of the present invention, the present invention is further described below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention.

[0030] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased through regular channels.

[0031] Example 1

[0032] This embodiment provides a method for preparing deep-low temperature freeze-dried breast milk powder.

[0033] 1. Breast milk collection and processing

[0034] Collect fresh breast milk: Choose healthy mothers for breast milk collection to ensure the quality of breast milk. Use sterile containers during the collection process to avoid any possible contamination.

[0035] Transportation conditions: During transportation, breast milk is kept in a low temperature environment of 4°C to 8°C to prevent degradation of components and loss of active factors. The transportation time should be shortened as much as possible to ensure that the breast milk is delivered to the processing location in the shortest time.

[0036] 2. Freezing treatment

[0037] Freezing temperature: The collected breast milk is frozen at -40°C to ensure the stability of the emulsion and avoid degradation of the components. The freezing time is 5 hours to ensure that the breast milk is completely frozen.

[0038] 3. Freeze-drying process

[0039] Equipment preparation: Turn on the power of the freeze dryer (Ningbo SCIENTZ-18N freeze dryer, power 1300W), wait for 3 minutes to ensure that the equipment starts normally. Press the refrigeration button, and when the temperature on the display drops to -40℃, prepare to put in the smoothie particles.

[0040] Preparation of smoothie particles: Use an ice crusher to make smoothies from frozen breast milk with a particle size of 6-8mm in diameter.

[0041] Tray configuration: A circular bracket with a height of 4 cm is placed on each tray, and another tray is placed on the bracket. Each freeze dryer can simultaneously put 8 trays, and the tray diameter is 24 cm. By increasing the number and height of trays, the surface area utilization rate of the sample is improved, and the volatilization rate of water is accelerated.

[0042] Freeze drying operation: Cover the glass cover to ensure good sealing, press the vacuum button to start cooling and vacuuming. When the temperature drops to -47℃ and the internal air pressure remains at 1Pa, it proves that the freeze dryer is operating normally. In this state, it takes 24 hours to complete freeze drying.

[0043] End freeze-drying: open the deflation valve, close the vacuum button after deflation is complete, open the glass cover, and take out the freeze-dried breast milk.

[0044] 4. Powder

[0045] Crushing process: Pour the freeze-dried breast milk into the grinder and make sure the upper cover of the grinder is fixed. Turn on the power, grind at a speed of 1800r / min for 15s, and collect the powder. This step ensures the fineness and uniformity of the freeze-dried milk powder.

[0046] 5. Filling

[0047] Packaging equipment: Use a granular powder packaging machine (Chuangfeng Machinery) to fill the freeze-dried milk powder into sealed bags. The sealed bags are made of aluminum foil film to ensure good barrier and moisture resistance.

[0048] Irradiation sterilization: Irradiation sterilization is carried out at a low temperature of 4°C, with an irradiation dose of 9kGy and an irradiation time of 10min to ensure that the safety of the product meets food safety standards.

[0049] Example 2

[0050] This embodiment provides a method for preparing deep-low temperature freeze-dried breast milk powder.

[0051] 1. Breast milk collection and processing

[0052] Collect fresh breast milk: Choose healthy mothers for breast milk collection to ensure the quality of breast milk. Use sterile containers during the collection process to avoid any possible contamination.

[0053] Transportation conditions: During transportation, breast milk is kept in a low temperature environment of 4°C to 8°C to prevent degradation of components and loss of active factors. The transportation time should be shortened as much as possible to ensure that the breast milk is delivered to the processing location in the shortest time.

[0054] 2. Freezing treatment

[0055] Freezing temperature: The collected breast milk is frozen at -20°C to ensure the stability of the milk and avoid degradation of its components. The freezing time is 5 hours to ensure that the breast milk is completely frozen.

[0056] 3. Freeze-drying process

[0057] Equipment preparation: Turn on the freeze dryer (Ningbo SCIENTZ-18N freeze dryer, power 1300W), wait for 3 minutes to ensure the equipment starts normally. Press the refrigeration button, and when the temperature on the display drops to -20℃, prepare to put in the smoothie particles.

[0058] Preparation of smoothie particles: Use an ice crusher to make smoothies from frozen breast milk with a particle size of 6-8mm in diameter.

[0059] Tray configuration: A circular bracket with a height of 3 cm is placed on each tray, and another tray is placed on the bracket. Each freeze dryer can simultaneously put 8 trays, and the tray diameter is 20 cm. By increasing the number and height of trays, the surface area utilization rate of the sample is improved, and the volatilization rate of water is accelerated.

[0060] Freeze drying operation: Cover the glass cover to ensure good sealing, press the vacuum button to start cooling and vacuuming. When the temperature drops to -47℃ and the internal air pressure remains at 1Pa, it proves that the freeze dryer is operating normally. In this state, it takes 25 hours to complete freeze drying.

[0061] End freeze-drying: open the deflation valve, close the vacuum button after deflation is complete, open the glass cover, and take out the freeze-dried breast milk.

[0062] 4. Powder

[0063] Crushing process: Pour the freeze-dried breast milk into the grinder and make sure the upper cover of the grinder is fixed. Turn on the power, grind at a speed of 1500r / min for 20s, and collect the powder. This step ensures the fineness and uniformity of the freeze-dried milk powder.

[0064] 5. Filling

[0065] Packaging equipment: Use a granular powder packaging machine (Chuangfeng Machinery) to fill the freeze-dried milk powder into sealed bags. The sealed bags are made of aluminum foil film to ensure good barrier and moisture resistance.

[0066] Irradiation sterilization: Irradiation sterilization is carried out at a low temperature of 2°C, with an irradiation dose of 8kGy and an irradiation time of 15min to ensure that the safety of the product meets food safety standards.

[0067] Example 3

[0068] This embodiment provides a method for preparing deep-low temperature freeze-dried breast milk powder.

[0069] 1. Breast milk collection and processing

[0070] Collect fresh breast milk: Choose healthy mothers for breast milk collection to ensure the quality of breast milk. Use sterile containers during the collection process to avoid any possible contamination.

[0071] Transportation conditions: During transportation, breast milk is kept in a low temperature environment of 4°C to 8°C to prevent degradation of components and loss of active factors. The transportation time should be shortened as much as possible to ensure that the breast milk is delivered to the processing location in the shortest time.

[0072] 2. Freezing treatment

[0073] Freezing temperature: The collected breast milk is frozen at -38°C to ensure the stability of the emulsion and avoid degradation of the components. The freezing time is 1 hour to ensure that the breast milk is completely frozen.

[0074] 3. Freeze-drying process

[0075] Equipment preparation: Turn on the freeze dryer (Ningbo SCIENTZ-18N freeze dryer, power 1300W) and wait for 3 minutes to ensure the equipment starts normally. Press the refrigeration button and when the temperature on the display drops to -38℃, prepare to put in the smoothie particles.

[0076] Preparation of smoothie particles: Use an ice crusher to make smoothies from frozen breast milk with a particle size of 6-8mm in diameter.

[0077] Tray configuration: A circular bracket with a height of 5 cm is placed on each tray, and another tray is placed on the bracket. Each freeze dryer can simultaneously put 8 trays, and the tray diameter is 20 cm. By increasing the number and height of trays, the surface area utilization rate of the sample is improved, and the volatilization rate of water is accelerated.

[0078] Freeze drying operation: Cover the glass cover to ensure good sealing, press the vacuum button to start cooling and vacuuming. When the temperature drops to -47℃ and the internal air pressure remains at 1Pa, it proves that the freeze dryer is operating normally. In this state, it takes 26 hours to complete freeze drying.

[0079] End freeze-drying: open the deflation valve, close the vacuum button after deflation is complete, open the glass cover, and take out the freeze-dried breast milk.

[0080] 4. Powder

[0081] Crushing process: Pour the freeze-dried breast milk into the grinder and make sure the upper cover of the grinder is fixed. Turn on the power, grind at a speed of 2000r / min for 10s, and collect the powder. This step ensures the fineness and uniformity of the freeze-dried milk powder.

[0082] 5. Filling

[0083] Packaging equipment: Use a granular powder packaging machine (Chuangfeng Machinery) to fill the freeze-dried milk powder into sealed bags. The sealed bags are made of aluminum foil film to ensure good barrier and moisture resistance.

[0084] Irradiation sterilization: Irradiation sterilization is carried out at a low temperature of 2°C, with an irradiation dose of 10kGy and an irradiation time of 15min to ensure that the safety of the product meets food safety standards.

[0085] Example 4

[0086] The difference between this embodiment and embodiment 1 is that the low temperature freezing during the freezing process is -50°C.

[0087] Example 5

[0088] The only difference between this embodiment and embodiment 1 is that the low-temperature freezing temperature during the freezing process is -10°C.

[0089] Example 6

[0090] The only difference between this embodiment and embodiment 1 is that the diameter of the ice smoothie particles is 1 cm.

[0091] Example 7

[0092] The only difference between this embodiment and embodiment 1 is that the diameter of the ice smoothie particles is 4 mm.

[0093] Example 8

[0094] The only difference between this embodiment and Embodiment 1 is that the number of trays is 4.

[0095] Example 9

[0096] The only difference between this embodiment and embodiment 1 is that the height of the bracket is 8 cm.

[0097] Comparative Example 1

[0098] The only difference between this comparative example and Example 1 is that the breast milk sample is not made into smoothie particles, and the freeze-drying step is directly performed after freezing.

[0099] Test Example 1

[0100] This test example tests the freeze-drying time of breast milk, where the freeze-drying time is the time taken for the breast milk to be completely frozen.

[0101] The results are shown in Table 1.

[0102] Table 1

[0103] Group Freeze drying time Example 1 24h Example 2 25h Example 3 26h Example 4 30h Example 5 31h Example 6 32h Example 7 31h Example 8 34h Example 9 32h Comparative Example 1 36h

[0104] It can be seen from the results in Table 1 that the method for preparing deep-low temperature breast milk freeze-dried powder in Examples 1-3 of the present invention has a short freeze-drying time of only 24-26 hours. The results of Examples 4-5 extend the freeze-drying time to 31 hours, indicating that the temperature of low-temperature freezing must be strictly controlled to ensure the freeze-drying efficiency. The results of Example 6 show that the ice smoothie particles are too large, resulting in prolonged freeze-drying time and reduced sublimation efficiency. The results of Example 7 show that the ice smoothie particles are too small, resulting in dense accumulation between particles, and the water sublimation path is blocked, affecting the freeze-drying efficiency. The results of Examples 8-9 show that increasing the number of trays and the height of the bracket improves the surface area utilization rate of the breast milk sample and accelerates the volatilization rate of water. The results of Comparative Example 1 show that adding ice smoothie can effectively shorten the freeze-drying time.

[0105] Test Example 2

[0106] This test example detects active factors in breast milk.

[0107] Immunoglobulin IgA was detected by immunoscattering turbidimetry, immunocytokines interleukin II (IL-2), interleukin IV (IL-4), interleukin VI (IL-6), tumor necrosis factor α (TNF-α) were detected by chemiluminescence, and albumin was detected by bromocresol green method. The retention rate of each component was calculated based on the data of each component before and after freeze-dried preparation. Component retention rate (%) = detection value before freeze-dried preparation / detection value after freeze-dried preparation * 100%. The retention rate of components before preparation is uniformly stipulated to be 100%. The results of Example 1 are shown in Table 2.

[0108] Table 2

[0109] project Before freeze-drying After freeze-dried preparation Retention rate (%) Total Protein 14.2 14.1 99.3 albumin 10 10 100.0 globulin 4.2 4.1 97.6 Immunoglobulin IgA 0.32 0.32 100.0 Interleukin Ⅱ (IL-2) 1.78 1.77 99.4 Interleukin Ⅳ (IL-4) 1.74 1.73 99.4 Interleukin VI (IL-6) 1.61 1.61 100.0 Tumor necrosis factor alpha (TNF-α) 2.92 2.9 99.3

[0110] Total mean value of retention rate = sum of retention rates of each component divided by the number of detected components. According to the data in Table 1, the total mean value of retention rate of the breast milk active factor in Example 1 is 99.4%.

[0111] The results of the total mean value of the retention rate of the breast milk active factors in each example are shown in Table 3.

[0112] Table 3

[0113] Group Before freeze-drying After freeze-dried preparation Example 1 100％ 99.4％ Example 2 100％ 98.4％ Example 3 100％ 98.7％ Example 4 100％ 95.2％ Example 5 100％ 95.1％ Example 6 100％ 95.3％ Example 7 100％ 96.5％ Example 8 100％ 94.8％ Example 9 100％ 95.1％ Comparative Example 1 100％ 90.4％

[0114] It can be seen from the results in Table 1 that the deep low temperature breast milk freeze-dried powder prepared by the methods of Examples 1-3 of the present invention contains more active factors and is rich in nutrition. The results of Examples 4-5 show that the temperature of low-temperature freezing must be strictly controlled to ensure the diversity of active factors in breast milk freeze-dried powder. The results of Example 6 show that the ice smoothie particles are too large, resulting in prolonged freeze-drying time and reduced content of active factors in breast milk freeze-dried powder. The results of Example 7 show that the ice smoothie particles are too small, resulting in dense accumulation between particles, and the water sublimation path is blocked, affecting the content of active factors in breast milk freeze-dried powder. The results of Examples 8-9 show that increasing the number of trays and the height of the bracket improves the surface area utilization rate of the breast milk sample, accelerates the volatilization rate of water, and is beneficial to ensure the diversity of active factors in breast milk freeze-dried powder. The results of Comparative Example 1 show that adding ice smoothie can effectively shorten the freeze-drying time and ensure the richness of active factors in breast milk freeze-dried powder.

[0115] In summary, the present invention processes breast milk through low-temperature freezing to prepare smoothie particles, thereby improving freeze-drying efficiency, reducing freeze-drying time, retaining more active factors, and extending the shelf life.

[0116] The applicant declares that the present invention illustrates the detailed method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed method, that is, it does not mean that the present invention must rely on the above-mentioned detailed method to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing deep-low temperature breast milk freeze-dried powder, characterized in that: The method comprises: collecting breast milk, freezing the breast milk at low temperature to make ice smoothie particles, and then freeze-drying the particles; and grinding the particles after freeze-drying to obtain the deep low temperature breast milk freeze-dried powder.

2. The method according to claim 1, characterized in that The temperature of the low-temperature freezing is -40°C to -20°C, and the time of the low-temperature freezing is 1-5h.

3. The method according to claim 1 or 2, characterized in that: The diameter of the ice smoothie particles is 6 to 8 mm.

4. The method according to any one of claims 1 to 3, characterized in that The freeze drying comprises: freeze drying using a freeze dryer with a support, the support being connected to a tray; Preferably, the number of the trays is 6 to 8, and the diameter of the tray is 20 to 28 cm.

5. The method according to claim 4, characterized in that The height of the bracket is 3 to 5 cm.

6. The method according to any one of claims 1 to 5, characterized in that The grinding speed is 1500-2000 r / min, and the grinding time is 10-20 s.

7. The method according to any one of claims 1 to 6, characterized in that The method also includes irradiating after grinding; Preferably, the irradiation temperature is 2°C to 5°C, the irradiation dose is 8 to 10 kGy, and the irradiation time is 5 to 15 min.

8. A deep low temperature breast milk freeze-dried powder, characterized in that: The deep-low temperature breast milk freeze-dried powder is prepared by the method described in any one of claims 1-7.

9. A freeze-dried breast milk powder product, characterized in that: The breast milk freeze-dried powder product contains the deep-temperature breast milk freeze-dried powder according to claim 8, and the mass percentage of the deep-temperature breast milk freeze-dried powder in the breast milk freeze-dried powder product is 1 to 99%.

10. Use of the deep-low temperature freeze-dried breast milk powder according to claim 8 or the freeze-dried breast milk powder product according to claim 9 in the preparation of a product for preventing and / or treating immunodeficiency.