High-protein milk and preparation method thereof

Abstract

The invention relates to the technical field of food, in particular to high-protein milk and a preparation method thereof.The preparation method comprises the steps that raw milk is sequentially subjected to milk purification, fat standardization, primary homogenization, pasteurization, concentration, secondary homogenization, protein maintenance, ultrahigh-temperature sterilization and sterile filling; the fat standardization comprises the step of adjusting the ratio of fat to protein in the raw milk to 1.11: 1-1.17: 1; the concentration comprises the step of concentrating the protein content of the pasteurized milk to 3.6 g / 100g or above. According to the invention, the proportion of fat and protein in the raw milk is adjusted in the purified milk separation process, so that the proportion is controlled within a specific range, and the problem of inconsistent product stability and taste of the high-protein milk can be effectively solved; by optimizing technological parameters such as primary homogenization, secondary homogenization and ultra-high-temperature sterilization, the use of food additives can be avoided, and meanwhile, the uniform taste of the product and the stable system can be effectively ensured.

Description

Technical Field

[0001] The invention relates to the technical field of food, and in particular to high-protein milk and a preparation method thereof. Background Art

[0002] As consumers' demand for food nutrition continues to grow, high-protein milk has been widely favored by the market due to its nutritional value.

[0003] At present, the processing technology for producing high-protein products is mainly based on the concentration and sterilization of milk. The specific process includes: raw milk inspection, milk purification, pasteurization, concentration, homogenization, ultra-high temperature sterilization and aseptic filling. Specifically, in the raw milk inspection stage, raw milk is inspected in accordance with the "GB 19301 National Food Safety Standard Raw Milk"; in the milk purification stage, the milk purifier effectively removes impurities in raw milk at 0~6℃; in the pasteurization stage, raw milk is sterilized at 75℃ and 15 seconds to prepare pasteurized milk; in the concentration stage, RO membrane technology is used to concentrate pasteurized milk to achieve the expected protein content; in the homogenization stage, 200~240bar pressure (secondary pressure 40~50bar) and 50~90℃ are used for homogenization of pasteurized milk; in the ultra-high temperature sterilization stage, 135~140℃ and 4~6 seconds are used to sterilize pasteurized milk; finally, the aseptic filling stage completes the product filling through an aseptic filling machine. However, the existing technology cannot guarantee the uniformity of the product in terms of taste and physical and chemical indicators, and it is difficult to maintain good stability during the shelf life. In addition, the fat and protein indicators of raw milk (raw milk) used to produce high-protein milk fluctuate due to factors such as season, region, and dairy cow breed, which not only leads to inconsistency in product taste and physical and chemical indicators, but also affects the stability of the product during the shelf life.

[0004] Generally speaking, the higher the protein content of the product and the longer the shelf life, the worse its stability. In order to improve product stability, the industry often uses the method of adding thickeners and emulsifiers. This process includes: raw milk inspection, milk purification, batching, mixing, concentration, homogenization, pasteurization, ultra-high temperature sterilization and aseptic filling. In the specific operation, the raw milk is heated to the optimal dissolution temperature of the thickener and emulsifier in the batching stage, and then added and fully dissolved; in the mixing stage, the raw milk after batching is fully mixed with the remaining raw milk. Although this technology can ensure the stability of the product, there are still problems in the consistency of taste and physical and chemical indicators, and food additives need to be identified in the product ingredient list. Clean product ingredients (labeling) are becoming a development trend in the food industry.

[0005] Therefore, it is very important to provide a preparation method for high-protein milk based on clean product ingredients and improvements to traditional processing technology that can ensure the product stability of high-protein milk. Summary of the invention

[0006] The present invention provides high-protein milk and a preparation method thereof, so as to solve the defects of high-protein milk with a protein content of more than 3.6g / 100g in the prior art, that is, the product is unstable or cannot meet the clean product label, realizes improvement based on clean product ingredients and traditional processing technology, and provides a preparation method of high-protein milk, which can ensure the product stability of high-protein milk.

[0007] Specifically, the present invention provides a method for preparing high-protein milk, characterized by comprising: sequentially subjecting raw milk to milk purification, fat standardization, primary homogenization, pasteurization, concentration, secondary homogenization, protein retention, ultra-high temperature sterilization, and aseptic filling; The fat standardization includes adjusting the ratio of fat to protein in raw milk to 1.11:1 to 1.17:1; The concentration includes concentrating the protein content of the pasteurized milk to above 3.6 g / 100 g.

[0008] Generally, the fat-to-protein ratio of raw milk that has only been treated with impurities removal fluctuates between 0.8:1 and 1.9:1. Studies have found that the fluctuation in the fat-to-protein ratio is an important factor causing inconsistent product taste and system instability. The present invention uses fat standardization to adjust the fat-to-protein ratio in raw milk to 1.11:1-1.17:1. Experimental verification shows that the consistency of product taste and system stability can be effectively guaranteed.

[0009] In the present invention, the ratio of fat to protein is adjusted to 1.11:1-1.17:1, for example, it can be any value among 1.11:1, 1.12:1, 1.13:1, 1.14:1, 1.15:1, 1.16:1 and 1.17:1, or a range formed between any values.

[0010] According to the method for preparing high-protein milk provided by the present invention, the secondary pressure of the primary homogenization is 25~35 bar.

[0011] In the present invention, the secondary pressure of the primary homogenization is 25~35 bar, for example, it can be any value among 25 bar, 26 bar, 27 bar, 28 bar, 29 bar, 30 bar, 31 bar, 32 bar, 33 bar, 34 bar and 35 bar, or a range formed between any values.

[0012] According to the method for preparing high-protein milk provided by the present invention, the secondary pressure of the secondary homogenization is 25~35 bar.

[0013] In the present invention, the secondary pressure of the secondary homogenization is 25~35 bar, for example, it can be any value among 25 bar, 26 bar, 27 bar, 28 bar, 29 bar, 30 bar, 31 bar, 32 bar, 33 bar, 34 bar and 35 bar, or a range formed between any values.

[0014] Commonly used homogenization secondary pressure (including primary and secondary homogenization): total pressure ≈ 20%. Studies have found that the present invention adopts the above-mentioned secondary pressure to obtain the best homogenization effect and effectively promote the stability of the product system.

[0015] According to the method for preparing the high-protein milk provided by the present invention, the protein preservation comprises preserving the protein of the milk after the secondary homogenization at a temperature of 85-95°C.

[0016] In the present invention, the protein is maintained at 85-95°C, wherein the temperature can be, for example, any value of 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C or a range formed between any values.

[0017] According to the method for preparing the high-protein milk provided by the present invention, the ultra-high temperature sterilization is carried out at 136-138°C.

[0018] Generally, the ultra-high temperature sterilization parameters of the ultra-high temperature sterilization process are set at 135-140° C. The present invention adopts the above range, which is beneficial to the taste and stability of the high-protein milk of the present invention.

[0019] In the present invention, the step of performing the step at a temperature of 136-138° C. may be any value among 136° C., 137° C. and 138° C. or a range formed between any values.

[0020] According to the method for preparing high-protein milk provided by the present invention, the fat standardization adopts a milk separator with fat standardization capability to adjust the ratio of fat and protein.

[0021] The milk purifying separator used in the present invention can take into account the functions of milk purifying and fat standardization, thus realizing "one machine with multiple effects".

[0022] According to the method for preparing the high-protein milk provided by the present invention, the concentration uses an RO membrane to concentrate the protein content of the pasteurized milk to 3.6-4.5 g / 100 g.

[0023] In the experiment, it was found that if the protein content is greater than 4.5g / 100mL, on the one hand, the acidity of the product will be higher than 18, and on the other hand, the product system will be unstable.

[0024] In the present invention, the protein content is concentrated to 3.6-4.5 g / 100 g, for example, it can be any value among 3.6 g / 100 g, 3.7 g / 100 g, 3.8 g / 100 g, 3.9 g / 100 g, 4.0 g / 100 g, 4.1 g / 100 g, 4.2 g / 100 g, 4.3 g / 100 g, 4.4 g / 100 g and 4.5 g / 100 g, or a range formed between any values.

[0025] According to the method for preparing high-protein milk provided by the present invention, the process flow adopted comprises in sequence: clean milk separation, cooling storage, primary homogenization, pasteurization, cooling, concentration, cooling storage, secondary homogenization, stable maintenance, ultra-high temperature sterilization, cooling, aseptic storage and aseptic filling; The clean milk separation includes clean milk and the fat standardization.

[0026] The preparation method of the present invention comprises the following specific steps: (1) Clean milk separation: removing impurities from raw milk and performing fat standardization at a temperature of 45-55°C.

[0027] The milk purification and separation process of the present invention is carried out under the temperature condition of 45-55° C., which can ensure the effect of milk purification and fat separation and reduce the troubleshooting loss of the separator to the greatest extent.

[0028] (2) First cooling storage: chilling the fat-standardized raw milk to 0-4°C.

[0029] (3) Primary homogenization: homogenizing the raw milk after the first cooling and storage under the conditions of a total homogenization pressure of 100-120 bar and secondary pressure parameters.

[0030] (4) Pasteurization: The raw milk after the primary homogenization is pasteurized to prepare pasteurized milk; the pasteurization temperature is 75° C. and the time is 15 seconds.

[0031] (5) First cooling: cooling the pasteurized milk to 1-7°C.

[0032] (6) Concentration: The milk after the first cooling is concentrated using an RO membrane.

[0033] (7) Second cooling storage: cooling the pasteurized milk to 1-7°C.

[0034] (8) Secondary homogenization: homogenize the milk after the second cooling and storage under the parameter conditions of total pressure of 220-250 bar, secondary pressure, and homogenization temperature of 70-80°C.

[0035] (9) Protein retention: The protein of the milk after the secondary homogenization is retained for 60 to 120 seconds.

[0036] (10) Ultra-high temperature sterilization: The milk after the protein retention is subjected to ultra-high temperature sterilization for 4 to 6 seconds.

[0037] (11) Second cooling: Cooling the ultra-high temperature sterilized milk to 15-35°C.

[0038] (12) Aseptic storage: The milk after the second cooling is stored as an aseptic liquid.

[0039] (13) Aseptic filling: filling the aseptically stored milk into products.

[0040] Further preferably, the method for preparing high-protein milk of the present invention adopts a continuous production line for production.

[0041] Wherein, the clean milk separation is carried out using a clean milk separator from Tetra Pak.

[0042] The first cooling storage is performed using a cold plate from Tetra Pak.

[0043] The primary homogenization is performed using a Tetra Pak homogenizer.

[0044] The pasteurization is carried out using a pasteurization machine from Tetra Pak.

[0045] The first cooling is performed using a cold plate from Tetra Pak.

[0046] The concentration adopts Tetra Pak RO membrane (reverse osmosis membrane).

[0047] The second cooling storage is performed using a cold plate from Tetra Pak.

[0048] The secondary homogenization is performed using a Tetra Pak homogenizer.

[0049] The protein retention is performed using a tubular retention tube.

[0050] The ultra-high temperature sterilization is carried out using an ultra-high temperature sterilizer from Tetra Pak.

[0051] The second cooling is performed using a tubular cooling tube from Tetra Pak.

[0052] The aseptic storage is carried out using Tetra Pak aseptic tanks.

[0053] The aseptic filling is performed using a Tetra Pak aseptic filling machine.

[0054] The present invention also provides high-protein milk prepared by the high-protein milk preparation method as described above.

[0055] The high-protein milk provided according to the present invention has a protein content of 3.6 g / 100 g or more.

[0056] The present invention provides a high-protein milk and a preparation method thereof, which can effectively solve the problems of product stability and inconsistent taste of high-protein milk by adjusting the ratio of raw milk fat to protein in the pure milk separation process to control it within a specific range.

[0057] Furthermore, the present invention also limits the total homogenization pressure and secondary pressure in the primary homogenization process to promote the stability of the product system and achieve energy saving and consumption reduction, limits the total homogenization pressure, secondary pressure, and homogenization temperature in the secondary homogenization process to promote the stability of the product system, and limits the sterilization temperature range in the ultra-high temperature sterilization process, which can avoid the use of food additives and effectively ensure the uniform taste of the product and the stability of the system. Thus, the improvement of traditional processing technology is achieved as a whole, and a preparation method for high-protein milk based on clean product ingredients is proposed. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0059] 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.

[0060] The raw milk used in the present invention is all inspected and accepted according to the standard "GB 19301 National Food Safety Standard Raw Milk" and used after passing the inspection. However, in different embodiments and comparative examples, the fat to protein ratio of the raw milk used fluctuates between 0.8:1 and 1.9:1.

[0061] Example 1 This embodiment provides a method for preparing high-protein milk, and the steps are as follows: (1) Milk separation process: Tetra Pak's milk separator with fat standardization capability is used to remove impurities in raw milk at a temperature of 45°C and adjust the fat-protein ratio in the raw milk to 1.11:1.

[0062] (2) First cooling and storage process: Use Tetra Pak's cold plate to cool the raw milk after the clean milk separation process to 2°C.

[0063] (3) Primary homogenization process: The chilled raw milk was homogenized using a Tetra Pak homogenizer under the parameters of a total homogenization pressure of 100 bar and a secondary pressure of 25 bar.

[0064] (4) Pasteurization process: The raw milk after the homogenization process is pasteurized using a Tetra Pak pasteurizer to prepare pasteurized milk; the pasteurization temperature is 75°C and the time is 15 seconds.

[0065] (5) First cooling process: Use Tetra Pak cold plates to cool the pasteurized milk to 1°C.

[0066] (6) Concentration process: The milk after the first cooling process is concentrated using Tetra Pak RO membrane to concentrate its protein content to 3.6 g / 100 g.

[0067] (7) Second cooling and storage process: Use Tetra Pak cold plates to cool the concentrated milk to 1°C.

[0068] (8) Secondary homogenization process: The milk after the second cooling and storage process was homogenized using a Tetra Pak homogenizer under the following parameters: total pressure of 220 bar, secondary pressure of 25 bar, and homogenization temperature of 70 °C.

[0069] (9) Protein retention process: A tubular retention tube is used to retain the protein of the milk after the secondary homogenization process at 85°C and 60 seconds.

[0070] (10) Ultra-high temperature sterilization process: The milk after the protein retention process is sterilized using a Tetra Pak ultra-high temperature sterilizer at 136°C for 5 seconds.

[0071] (11) Second cooling process: The milk after the ultra-high temperature sterilization process is cooled to 15°C using Tetra Pak tubular cooling tubes.

[0072] (12) Aseptic storage process: Use Tetra Pak aseptic tanks to store the milk after the second cooling process as aseptic liquid.

[0073] (13) Aseptic filling process: Tetra Pak aseptic filling machine is used to fill the milk after the aseptic storage process.

[0074] Example 2 This embodiment provides a method for preparing high-protein milk, and the steps are as follows: (1) Milk separation process: Tetra Pak's milk separator with fat standardization capability is used to remove impurities in raw milk at a temperature of 50°C and adjust the ratio of fat to protein in the raw milk to 1.14:1.

[0075] (2) First cooling and storage process: Use Tetra Pak's cold plate to cool the raw milk after the clean milk separation process to 3°C.

[0076] (3) Primary homogenization process: The chilled raw milk was homogenized using a Tetra Pak homogenizer under the parameters of a total homogenization pressure of 110 bar and a secondary pressure of 30 bar.

[0077] (4) Pasteurization process: The raw milk after the homogenization process is pasteurized using a Tetra Pak pasteurizer to prepare pasteurized milk; the pasteurization temperature is 75°C and the time is 15 seconds.

[0078] (5) First cooling process: Use Tetra Pak cold plates to cool the pasteurized milk to 4°C.

[0079] (6) Concentration process: The milk after the first cooling process is concentrated using Tetra Pak RO membrane to concentrate its protein content to 4 g / 100 g.

[0080] (7) Second cooling and storage process: Use Tetra Pak cold plates to cool the concentrated milk to 4°C.

[0081] (8) Secondary homogenization process: The milk after the second cooling and storage process was homogenized using a Tetra Pak homogenizer under the following parameters: total pressure of 235 bar, secondary pressure of 30 bar, and homogenization temperature of 75 °C.

[0082] (9) Protein retention process: A tubular retention tube is used to retain the protein of the milk after the secondary homogenization process at 90°C and 90 seconds.

[0083] (10) Ultra-high temperature sterilization process: The milk after the protein retention process is sterilized at 137°C for 5 seconds using Tetra Pak’s ultra-high temperature sterilizer.

[0084] (11) Second cooling process: The milk after the ultra-high temperature sterilization process is cooled to 25°C using Tetra Pak tubular cooling tubes.

[0085] (12) Aseptic storage process: Use Tetra Pak aseptic tanks to store the milk after the second cooling process as aseptic liquid.

[0086] (13) Aseptic filling process: Tetra Pak aseptic filling machine is used to fill the milk after the aseptic storage process.

[0087] Example 3 This embodiment provides a method for preparing high-protein milk, and the steps are as follows: (1) Milk separation process: Tetra Pak's milk separator with fat standardization capability is used to remove impurities in raw milk at a temperature of 55°C and adjust the ratio of fat to protein in the raw milk to 1.17:1.

[0088] (2) First cooling and storage process: Use Tetra Pak's cold plate to cool the raw milk after the clean milk separation process to 4°C.

[0089] (3) Primary homogenization process: The chilled raw milk was homogenized using a Tetra Pak homogenizer under the parameters of a total homogenization pressure of 120 bar and a secondary pressure of 35 bar.

[0090] (4) Pasteurization process: The raw milk after the homogenization process is pasteurized using a Tetra Pak pasteurizer to prepare pasteurized milk; the pasteurization temperature is 75°C and the time is 15 seconds.

[0091] (5) First cooling process: Use Tetra Pak cold plates to cool the pasteurized milk to 7°C.

[0092] (6) Concentration process: The milk after the first cooling process is concentrated using Tetra Pak RO membrane to concentrate its protein content to 4.5 g / 100 g.

[0093] (7) Second cooling and storage process: Use Tetra Pak cold plates to cool the concentrated milk to 7°C.

[0094] (8) Secondary homogenization process: The milk after the second cooling and storage process is homogenized using a Tetra Pak homogenizer under the following parameter conditions: total pressure of 250 bar, secondary pressure of 35 bar, and homogenization temperature of 80 °C.

[0095] (9) Protein retention process: A tubular retention tube is used to retain the protein of the milk after the secondary homogenization process at 95°C and 120 seconds.

[0096] (10) Ultra-high temperature sterilization process: The milk after the protein retention process is sterilized at 138°C for 5 seconds using Tetra Pak’s ultra-high temperature sterilizer.

[0097] (11) Second cooling process: The milk after the ultra-high temperature sterilization process is cooled to 35°C using Tetra Pak tubular cooling tubes.

[0098] (12) Aseptic storage process: Use Tetra Pak aseptic tanks to store the milk after the second cooling process as aseptic liquid.

[0099] (13) Aseptic filling process: Tetra Pak aseptic filling machine is used to fill the milk after the aseptic storage process.

[0100] Example 4 This embodiment provides a method for preparing high-protein milk, and the steps are as follows: (1) Milk separation process: Tetra Pak's milk separator with fat standardization capability is used to remove impurities in raw milk at a temperature of 55°C and adjust the ratio of fat to protein in the raw milk to 1.17:1.

[0101] (2) First cooling and storage process: Use Tetra Pak's cold plate to cool the raw milk after the clean milk separation process to 4°C.

[0102] (3) Primary homogenization process: The chilled raw milk was homogenized using a Tetra Pak homogenizer under the parameters of a total homogenization pressure of 120 bar and a secondary pressure of 35 bar.

[0103] (4) Pasteurization process: The raw milk after the homogenization process is pasteurized using a Tetra Pak pasteurizer to prepare pasteurized milk; the pasteurization temperature is 75°C and the time is 15 seconds.

[0104] (5) First cooling process: Use Tetra Pak cold plates to cool the pasteurized milk to 7°C.

[0105] (6) Concentration process: The milk after the first cooling process is concentrated using Tetra Pak RO membrane to concentrate its protein content to 3.6 g / 100 g.

[0106] (7) Second cooling and storage process: Use Tetra Pak cold plates to cool the concentrated milk to 7°C.

[0107] (8) Secondary homogenization process: The milk after the second cooling and storage process is homogenized using a Tetra Pak homogenizer under the following parameter conditions: total pressure of 250 bar, secondary pressure of 35 bar, and homogenization temperature of 80 °C.

[0108] (9) Protein retention process: A tubular retention tube is used to retain the protein of the milk after the secondary homogenization process at 95°C and 120 seconds.

[0109] (10) Ultra-high temperature sterilization process: The milk after the protein retention process is sterilized at 138°C for 5 seconds using Tetra Pak’s ultra-high temperature sterilizer.

[0110] (11) Second cooling process: The milk after the ultra-high temperature sterilization process is cooled to 35°C using Tetra Pak tubular cooling tubes.

[0111] (12) Aseptic storage process: Use Tetra Pak aseptic tanks to store the milk after the second cooling process as aseptic liquid.

[0112] (13) Aseptic filling process: Tetra Pak aseptic filling machine is used to fill the milk after the aseptic storage process.

[0113] Example 5 This embodiment provides a method for preparing high-protein milk, and the steps are as follows: (1) Milk separation process: Tetra Pak's milk separator with fat standardization capability is used to remove impurities in raw milk at a temperature of 45°C and adjust the fat-protein ratio in the raw milk to 1.11:1.

[0114] (2) First cooling and storage process: Use Tetra Pak's cold plate to cool the raw milk after the clean milk separation process to 2°C.

[0115] (3) Primary homogenization process: The chilled raw milk was homogenized using a Tetra Pak homogenizer under the parameters of a total homogenization pressure of 100 bar and a secondary pressure of 25 bar.

[0116] (4) Pasteurization process: The raw milk after the homogenization process is pasteurized using a Tetra Pak pasteurizer to prepare pasteurized milk; the pasteurization temperature is 75°C and the time is 15 seconds.

[0117] (5) First cooling process: Use Tetra Pak cold plates to cool the pasteurized milk to 1°C.

[0118] (6) Concentration process: The milk after the first cooling process is concentrated using Tetra Pak RO membrane to concentrate its protein content to 4.5 g / 100 g.

[0119] (7) Second cooling and storage process: Use Tetra Pak cold plates to cool the concentrated milk to 1°C.

[0120] (8) Secondary homogenization process: The milk after the second cooling and storage process was homogenized using a Tetra Pak homogenizer under the following parameters: total pressure of 220 bar, secondary pressure of 25 bar, and homogenization temperature of 70 °C.

[0121] (9) Protein retention process: A tubular retention tube is used to retain the protein of the milk after the secondary homogenization process at 85°C and 60 seconds.

[0122] (10) Ultra-high temperature sterilization process: The milk after the protein retention process is sterilized using a Tetra Pak ultra-high temperature sterilizer at 136°C for 5 seconds.

[0123] (11) Second cooling process: The milk after the ultra-high temperature sterilization process is cooled to 15°C using Tetra Pak tubular cooling tubes.

[0124] (12) Aseptic storage process: Use Tetra Pak aseptic tanks to store the milk after the second cooling process as aseptic liquid.

[0125] (13) Aseptic filling process: Tetra Pak aseptic filling machine is used to fill the milk after the aseptic storage process.

[0126] Example 6 This embodiment provides a method for preparing high-protein milk, and the steps are as follows: (1) Milk separation process: Tetra Pak's milk separator with fat standardization capability is used to remove impurities in raw milk at a temperature of 45°C and adjust the fat-protein ratio in the raw milk to 1.11:1.

[0127] (2) First cooling and storage process: Use Tetra Pak's cold plate to cool the raw milk after the clean milk separation process to 2°C.

[0128] (3) Primary homogenization process: The chilled raw milk was homogenized using a Tetra Pak homogenizer under the parameters of a total homogenization pressure of 100 bar and a secondary pressure of 25 bar.

[0129] (4) Pasteurization process: The raw milk after the homogenization process is pasteurized using a Tetra Pak pasteurizer to prepare pasteurized milk; the pasteurization temperature is 75°C and the time is 15 seconds.

[0130] (5) First cooling process: Use Tetra Pak cold plates to cool the pasteurized milk to 1°C.

[0131] (6) Concentration process: The milk after the first cooling process is concentrated using Tetra Pak RO membrane to concentrate its protein content to 4 g / 100 g.

[0132] (7) Second cooling and storage process: Use Tetra Pak cold plates to cool the concentrated milk to 1°C.

[0133] (8) Secondary homogenization process: The milk after the second cooling and storage process was homogenized using a Tetra Pak homogenizer under the following parameters: total pressure of 220 bar, secondary pressure of 25 bar, and homogenization temperature of 70 °C.

[0134] (9) Protein retention process: A tubular retention tube is used to retain the protein of the milk after the secondary homogenization process at 85°C and 60 seconds.

[0135] (10) Ultra-high temperature sterilization process: The milk after the protein retention process is sterilized using a Tetra Pak ultra-high temperature sterilizer at 136°C for 5 seconds.

[0136] (11) Second cooling process: The milk after the ultra-high temperature sterilization process is cooled to 15°C using Tetra Pak tubular cooling tubes.

[0137] (12) Aseptic storage process: Use Tetra Pak aseptic tanks to store the milk after the second cooling process as aseptic liquid.

[0138] (13) Aseptic filling process: Tetra Pak aseptic filling machine is used to fill the milk after the aseptic storage process.

[0139] Example 7 This embodiment provides a method for preparing high-protein milk, and the steps are as follows: (1) Milk separation process: Tetra Pak's milk separator with fat standardization capability is used to remove impurities in raw milk at a temperature of 54°C and adjust the ratio of fat to protein in the raw milk to 1.14:1.

[0140] (2) First cooling and storage process: Use Tetra Pak's cold plate to cool the raw milk after the clean milk separation process to 3°C.

[0141] (3) Primary homogenization process: The chilled raw milk was homogenized using a Tetra Pak homogenizer under the parameters of a total homogenization pressure of 110 bar and a secondary pressure of 30 bar.

[0142] (4) Pasteurization process: The raw milk after the homogenization process is pasteurized using a Tetra Pak pasteurizer to prepare pasteurized milk; the pasteurization temperature is 75°C and the time is 15 seconds.

[0143] (5) First cooling process: Use Tetra Pak cold plates to cool the pasteurized milk to 4°C.

[0144] (6) Concentration process: The milk after the first cooling process is concentrated using Tetra Pak RO membrane to concentrate its protein content to 4 g / 100 g.

[0145] (7) Second cooling and storage process: Use Tetra Pak cold plates to cool the concentrated milk to 4°C.

[0146] (8) Secondary homogenization process: The milk after the second cooling and storage process was homogenized using a Tetra Pak homogenizer under the following parameters: total pressure of 235 bar, secondary pressure of 30 bar, and homogenization temperature of 75 °C.

[0147] (9) Protein retention process: A tubular retention tube is used to retain the protein of the milk after the secondary homogenization process at 90°C and 90 seconds.

[0148] (10) Ultra-high temperature sterilization process: The milk after the protein retention process is sterilized at 137°C for 5 seconds using Tetra Pak’s ultra-high temperature sterilizer.

[0149] (11) Second cooling process: The milk after the ultra-high temperature sterilization process is cooled to 25°C using Tetra Pak tubular cooling tubes.

[0150] (12) Aseptic storage process: Use Tetra Pak aseptic tanks to store the milk after the second cooling process as aseptic liquid.

[0151] (13) Aseptic filling process: Tetra Pak aseptic filling machine is used to fill the milk after the aseptic storage process.

[0152] Comparative Example 1 This comparative example provides a method for preparing high-protein milk, and the steps are as follows: (1) Milk purification process: Tetra Pak milk purifier is used to remove impurities in raw milk.

[0153] (2) First cooling and storage process: Use Tetra Pak's cold plate to cool the raw milk after the milk purification process to 3°C.

[0154] (3) Mixing process: Heat a portion of raw milk to 75°C, then add carrageenan and monoglyceride and fully dissolve them.

[0155] (4) Mixing process: fully mix the mixed raw milk with the remaining raw milk.

[0156] (5) Primary homogenization process: The mixed raw milk was homogenized using a Tetra Pak homogenizer under the parameters of a total homogenization pressure of 150 bar and a secondary pressure of 30 bar.

[0157] (6) Pasteurization process: The raw milk after the homogenization process is pasteurized using a Tetra Pak pasteurizer to prepare pasteurized milk; the pasteurization temperature is 75°C and the time is 15 seconds.

[0158] (7) First cooling process: Use Tetra Pak cold plates to cool the pasteurized milk to 4°C.

[0159] (8) Concentration process: The milk after the first cooling process is concentrated using Tetra Pak RO membrane to concentrate its protein content to 3.6 g / 100 g.

[0160] (9) Second cooling and storage process: Use Tetra Pak cold plates to cool the pasteurized milk to 4°C.

[0161] (10) Secondary homogenization process: The milk after the second cooling and storage process was homogenized using a Tetra Pak homogenizer under the following parameter conditions: total pressure of 235 bar, secondary pressure of 47 bar, and homogenization temperature of 75 °C.

[0162] (11) Protein retention process: A tubular retention tube is used to retain the protein of the milk after the secondary homogenization process at 90°C and 60 seconds.

[0163] (12) Ultra-high temperature sterilization process: The milk after the protein retention process is sterilized using Tetra Pak's ultra-high temperature sterilizer at 137°C for 5 seconds.

[0164] (13) Second cooling process: The milk after the ultra-high temperature sterilization process is cooled to 25°C using Tetra Pak tubular cooling tubes.

[0165] (14) Aseptic storage process: Use Tetra Pak aseptic tanks to store the milk after the second cooling process as aseptic liquid.

[0166] (15) Aseptic filling process: Tetra Pak aseptic filling machine is used to fill the milk after the aseptic storage process.

[0167] Comparative Example 2 This comparative example is substantially the same as Example 1, except that in the clean milk separation step, the ratio of fat to protein in the raw milk is adjusted to 1.1:1.

[0168] Comparative Example 3 This comparative example is substantially the same as Example 1, except that in the clean milk separation step, the ratio of fat to protein in the raw milk is adjusted to 1.18:1.

[0169] Comparative Example 4 This comparative example is substantially the same as Example 4, except that in the clean milk separation step, the ratio of fat to protein in the raw milk is adjusted to 1.18:1.

[0170] Comparative Example 5 This comparative example is substantially the same as Example 3, except that in the clean milk separation step, the ratio of fat to protein in the raw milk is adjusted to 1.1:1.

[0171] Comparative Example 6 This comparative example is substantially the same as Example 3, except that in the clean milk separation step, the ratio of fat to protein in the raw milk is adjusted to 1.18:1.

[0172] Comparative Example 7 This comparative example is substantially the same as Example 5, except that in the clean milk separation step, the ratio of fat to protein in the raw milk is adjusted to 1.18:1.

[0173] Comparative Example 8 This comparative example is basically the same as Example 1, except that in the first homogenization process, the secondary pressure is 24 bar.

[0174] Comparative Example 9 This comparative example is basically the same as Example 1, except that in the secondary homogenization process, the secondary pressure is 24 bar.

[0175] Comparative Example 10 This comparative example is basically the same as Example 1, except that in the first homogenization process, the secondary pressure is 36 bar.

[0176] Comparative Example 11 This comparative example is basically the same as Example 1, except that in the secondary homogenization process, the secondary pressure is 36 bar.

[0177] Comparative Example 12 This comparative example is substantially the same as Example 5, except that in the concentration step, the protein content is concentrated to 4.6 g / 100 g.

[0178] Comparative Example 13 This comparative example is substantially the same as Example 3, except that the temperature is 84° C. during the protein holding step.

[0179] Comparative Example 14 This comparative example is substantially the same as Example 3, except that the temperature is 96° C. in the protein holding step.

[0180] Comparative Example 15 This comparative example is basically the same as Example 1, except that in the ultra-high temperature sterilization process, the sterilization temperature is 135°C.

[0181] Comparative Example 16 This comparative example is basically the same as Example 1, except that in the ultra-high temperature sterilization process, the sterilization temperature is 139°C.

[0182] The milk obtained in the above embodiment and comparative example was tested, and the testing method was as follows: Product taste test: The difference between the samples prepared by the comparative example and the standard samples was analyzed using the "GB / T12311-2012 Three-point Test for Sensory Analysis Method".

[0183] Product sensory inspection: After the samples are stored at room temperature for 180 days, the sensory requirements of GB25190-2010 "National Food Safety Standard Sterilized Milk" are used for evaluation.

[0184] Among them, the selection of standard samples for taste analysis: Principle ⑴ Collect product data throughout the year, first summarize the product fat and protein data, generate a histogram using Minitab software, and then select samples with the most concentrated fat and protein detection values ​​as standard samples; Principle (2) The protein label value of the standard sample and the control sample in the product nutritional composition table must be the same.

[0185] The test results are as follows:

[0186] It can be seen from the above test results that the present invention can avoid the use of food additives when producing high-protein milk products with a protein content of 3.6g / 100mL~4.5g / 100mL through the above method, while effectively ensuring the uniform taste and stable system of the high-protein milk products.

[0187] The product was analyzed for taste using the "GB / T12311-2012 Sensory Analysis Method Three-Point Test". Under the premise of the same protein content, there was no significant difference between the product taste and the standard sample. The product system stability was analyzed using the sensory requirements in the "National Food Safety Standard Sterilized Milk" and met the standards. It also met the product acidity of 12~18 specified in GB25190-2010 "National Food Safety Standard Sterilized Milk".

[0188] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing high-protein milk, characterized in that: include: The raw milk is sequentially subjected to milk purification, fat standardization, primary homogenization, pasteurization, concentration, secondary homogenization, protein retention, ultra-high temperature sterilization, and aseptic filling; The fat standardization includes adjusting the ratio of fat to protein in raw milk to 1.11:1 to 1.17:1; The concentration includes concentrating the protein content of the pasteurized milk to above 3.6 g / 100 g.

2. The method for preparing high-protein milk according to claim 1, characterized in that: The secondary pressure of the primary homogenization is 25~35bar.

3. The method for preparing high-protein milk according to claim 1, characterized in that: The secondary pressure of the secondary homogenization is 25-35 bar.

4. The method for preparing high-protein milk according to claim 1, characterized in that: The protein preservation includes preserving the protein of the milk after the secondary homogenization at a temperature of 85-95°C.

5. The method for preparing high-protein milk according to claim 1, characterized in that: The ultra-high temperature sterilization is carried out at 136-138°C.

6. The method for preparing high-protein milk according to claim 1, characterized in that: The fat standardization uses a milk separator with fat standardization capability to adjust the ratio of fat and protein.

7. The method for preparing high-protein milk according to claim 1, characterized in that: The concentration uses an RO membrane to concentrate the protein content of the pasteurized milk to 3.6-4.5 g / 100 g.

8. The method for preparing high-protein milk according to any one of claims 1 to 7, characterized in that: The process flow includes: pure milk separation, cooling storage, primary homogenization, pasteurization, cooling, concentration, cooling storage, secondary homogenization, stable maintenance, ultra-high temperature sterilization, cooling, aseptic storage and aseptic filling; The clean milk separation includes clean milk and the fat standardization.

9. High-protein milk obtained by the method for preparing high-protein milk according to any one of claims 1 to 8.

10. The high-protein milk according to claim 9, characterized in that: The protein content of the high-protein milk is above 3.6 g / 100 g.

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