Lactose-free high-calcium milk having double calcium content and preparation method therefor

Abstract

Lactose-free high-calcium milk having double calcium content and a preparation method therefor. The calcium content in the milk is 200 mg / 100 mL or above; the problem of particle precipitation caused by externally added suspended calcium is solved by using a stabilizer and a phosphate, and the problem of fat floating is solved by optimizing the preparation process; lactase is used to achieve zero lactose and generated galactooligosaccharide promotes high calcium absorption, and the browning degree of milk is also reduced, resulting in less observed fat floating in the milk.

Description

Lactose-free high-calcium milk with double calcium content and preparation method thereof

[0001] priority

[0002] This application claims the priority benefit of the Chinese patent application with application date of January 18, 2024, application number: 202410074214.7, and invention name: "A lactose-free, double calcium content high-calcium milk and its preparation method". Technical Field

[0003] The present invention relates to the technical field of liquid milk preparation, in particular to lactose-free high-calcium milk with double calcium content and a preparation method thereof. Background Art

[0004] Calcium demand in my country is increasing, while the average daily calcium intake is generally below the recommended daily intake. Milk is a high-quality source of calcium, but the calcium content of currently marketed room-temperature high-calcium milk is primarily claimed to be between 120-150mg / 100mL. Existing high-calcium milks have yet to achieve a calcium content exceeding 200mg / 100mL.

[0005] The calcium content of high-calcium milk is primarily achieved through the addition of exogenous calcium supplements. These supplements are typically water-insoluble calcium salts, which tend to settle during shelf life, resulting in substandard calcium content. Currently, the conventional method for suspending calcium supplements in high-calcium milk is to combine carrageenan and microcrystalline cellulose, adding glyceryl monostearate as an emulsifier to prevent fat from floating.

[0006] However, in high-calcium milk with a calcium content of 200mg / 100mL or more, the increased amount of exogenous calcium added significantly increases the amount of calcium ions in the milk product, disrupting its ionization balance and stability. This prevents the exogenous calcium from being suspended, exacerbating the problem of fat floating. As a result of these issues, no high-calcium milk with a calcium content of 200mg / 100mL or more has yet been released. Summary of the Invention

[0007] The present invention aims to provide a high-calcium milk with a calcium content of more than 200 mg / 100 mL.

[0008] In a first aspect, in the high-calcium milk provided by the present invention, the mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is (992-995):(4-5):(0.26-1.7):(0.5-1); in the stabilizer, the mass ratio of carrageenan, gellan gum and citrus fiber is (0-0.3):(0.23-0.4):(0-1).

[0009] The present invention uses a significantly higher amount of exogenous calcium than that used in prior art. To achieve suspension of the exogenous calcium, the present invention proposes the use of carrageenan, gellan gum, and citrus fiber as stabilizers for the first time, and provides an optimal ratio of carrageenan, gellan gum, and citrus fiber. After the exogenous calcium is added, some free calcium ions remain unsuspended. The present invention uses phosphate to chelate the free calcium ions in the milk system.

[0010] Specifically, in the high-calcium milk of the present invention, the phosphate includes one or both of sodium tripolyphosphate and sodium hexametaphosphate.

[0011] In addition to the suspension problem of exogenous calcium supplements, milk with a high calcium content will cause increased fat floating. The present invention slows down fat floating by standardizing the fat content of raw milk. Specifically, the fat content of the raw milk in the formula of the high-calcium milk of the present invention is 3.5-4.0g / 100g.

[0012] The high calcium milk provided by the present invention also includes: Nurica TM Lactase. Specifically, the lactase used in the present invention is Nurica TM Lactase. Using Nurica TM Lactase can not only achieve zero lactose, but also the oligosaccharides produced by lactase promote high calcium absorption. At the same time, the lower reducing sugar content in milk reduces the browning degree of milk. Therefore, the high-calcium milk prepared by the present invention has less fat floating in the milk observed from the sensory visual level.

[0013] As a specific embodiment of the present invention, the high calcium milk provided by the present invention comprises 992-995 parts by weight of raw cow's milk, 3-5 parts by weight of milk mineral salt, 0.1-0.3 parts by weight of carrageenan, 0.23-0.40 parts by weight of gellan gum, 0.2-1.0 parts by weight of citrus fiber, 0.1-0.5 parts by weight of sodium tripolyphosphate, 0.1-0.5 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.010-0.035 parts by weight.

[0014] As a more preferred formula, the high calcium milk provided by the present invention comprises 992-995 parts by weight of raw cow's milk, 4.0-4.6 parts by weight of milk mineral salts, 0.1-0.3 parts by weight of carrageenan, 0.23-0.35 parts by weight of gellan gum, 0.2-0.8 parts by weight of citrus fiber, 0.1-0.5 parts by weight of sodium tripolyphosphate, 0.1-0.5 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.010-0.035 parts by weight.

[0015] In a second aspect, the present invention provides a method for preparing the above-mentioned high-calcium milk, comprising: premixing, mixing, volume setting, sterilization and homogenization, secondary sterilization and homogenization, enzymolysis and enzyme inactivation;

[0016] The process comprises: stirring milk mineral salts and a stabilizer in raw milk at 35-55° C. for 3-10 minutes, adding phosphate and vitamin D3, stirring for 3-10 minutes, and continuously heating to 70-90° C. and stirring for 10-30 minutes to complete the process; during the process, the weight of the raw milk is 30-160 times the total weight of the milk mineral salts, the stabilizer, the phosphate and the vitamin D3;

[0017] The total pressure of the secondary sterilization and homogenization is 230-260 bar, and the secondary pressure is 25-60 bar.

[0018] The preparation method provided by the present invention comprises:

[0019] (1) Pre-treating raw milk to obtain raw milk.

[0020] (2) Premix milk mineral salts and stabilizers; premix phosphate and vitamin D3.

[0021] (3) After heating the raw milk obtained in step (1), the milk mineral salts and stabilizers premixed in step (2), as well as the premixed phosphates and vitamin D3 are added to the raw milk to obtain a mixed liquid.

[0022] (4) adding the remaining raw milk to the mixed liquid obtained in step (3), sterilizing and homogenizing the mixture, and performing secondary sterilization and homogenization to obtain a high-calcium milk semi-finished product.

[0023] (5) Add Nurica to the high calcium milk semi-finished product obtained in step (4) TM After enzymatic hydrolysis with lactase, the enzyme is inactivated to obtain the high-calcium milk.

[0024] As a specific embodiment of the present invention, the preparation method provided by the present invention comprises:

[0025] 1) Raw milk fat standardization: Use centrifugation and other methods to control the raw milk fat content to 3.5-4.0g / 100g.

[0026] The preferred raw milk fat content is 3.5-3.7g / 100g.

[0027] 2) Premix: premix milk mineral salts and stabilizers; premix phosphate and vitamin D3.

[0028] 3) Chemical processing: Pour 30-160 times the total mass of raw milk into the chemical processing tank. Make sure that the raw milk does not fall below the minimum stirring level. When the temperature reaches 35-55°C, add pre-mixed milk mineral salts and stabilizers from the high-speed shear port and stir for 3-10 minutes. Then continue to add pre-mixed phosphates and vitamin D3 and stir for 3-10 minutes. Continue to heat to 70-90°C and continue stirring for 10-30 minutes to ensure that all raw materials are fully dissolved.

[0029] Preferably, the amount of raw milk used is 50-140 times the total mass of the raw materials.

[0030] 4) Inspection: Take an appropriate amount of liquid and place it in a steel basin. Observe it under natural light or light. The color of the liquid should be uniform and there should be no particles in the structure.

[0031] 5) Mixing: After the dissolved liquid is passed through a 2.00mm filter, it is fully mixed with raw milk in a mixing tank and then transferred to a buffer tank.

[0032] 6) Homogenization sterilization: homogenization temperature 50-80℃, homogenization total pressure 140-180bar (secondary pressure 30-60bar); sterilization conditions 80-90℃ / 15-30s.

[0033] 7) Volume adjustment: Add raw milk to the mixed liquid and adjust the volume to the desired semi-finished product quality. If the production requirements of high-calcium milk have been met after mixing in step 5), step 7) can be omitted.

[0034] 8) Ultra-high temperature sterilization by homogenization: homogenization temperature 60-90°C, homogenization total pressure 230-260 bar (secondary pressure 25-60 bar); sterilization conditions: 135-145°C / 2-20s.

[0035] The preferred homogenization total pressure is 235-255 bar (secondary pressure 30-50 bar).

[0036] 9) Aseptic addition: Add Nurica under aseptic conditions TM Lactase.

[0037] 10) Enzymolysis: Enzymolysis at 25-45°C for 2-5 hours.

[0038] 11) Inactivate enzyme: 80-90℃ / 15-30s.

[0039] Beneficial effects of the present invention:

[0040] During production, this invention uses a combination of gellan gum, carrageenan, and citrus fiber in a specific ratio to suspend a large amount of molecular calcium from milk mineral salts, achieving a calcium content of ≥200mg / 100mL in a high-calcium milk product. This invention pioneers the use of double calcium, meaning the calcium content is twice that of conventional pure milk. Furthermore, the invention utilizes a combination of phosphates in a specific ratio to chelate more calcium ions in the system, maintaining product stability and minimizing the impact of addition on milk flavor.

[0041] The present invention standardizes the fat content of raw milk during production, controls the fat content of the product, and simultaneously controls the homogenization pressure, effectively alleviating fat buoyancy. In the high-calcium milk preparation process, the present invention optimizes the order and multiple of ingredient batching, increasing product stability and reducing the amount of raw material precipitation and fat buoyancy during shelf life.

[0042] The present invention uses Nurica in production TM Lactase achieves zero lactose and produces galacto-oligosaccharides to promote high calcium absorption, while reducing the reducing sugar content in milk, reducing the degree of milk browning, and visually slowing down the effect of fat floating. DETAILED DESCRIPTION

[0043] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention are described clearly and completely below. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0044] Example 1

[0045] This embodiment provides a lactose-free high-calcium milk with double calcium content and a preparation method thereof.

[0046] The formula of high calcium milk in this embodiment is: 994.93 parts by weight of raw milk, 4 parts by weight of milk mineral salt, 0.26 parts by weight of gellan gum, 0.5 parts by weight of sodium hexametaphosphate, Nurica TM 0.3 parts by weight of lactase and 0.01 parts by weight of vitamin D3.

[0047] In this embodiment, the mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 994.93:4:0.26:0.5.

[0048] The preparation method of this embodiment includes:

[0049] 1) Raw milk fat standardization: Raw cow milk with a fat content of 3.5 g / 100 g was obtained as raw material.

[0050] 2) Premix: premix milk mineral salt and stabilizer; premix phosphate and vitamin D3.

[0051] 3) Chemical Processing: 50 times the total mass of the premix obtained in step 2) was added to the chemical process tank. It was necessary to ensure that the raw milk did not fall below the minimum stirring level. When the temperature was raised to 35°C, the premixed milk mineral salts and stabilizer were added from the high-speed shear port and stirred for 3 minutes. Then, the premixed phosphate and vitamin D3 were added and stirred for 3 minutes. The temperature was continued to rise to 70°C and stirred for 10 minutes to ensure that all the raw materials were fully dissolved.

[0052] 4) Inspection: Take an appropriate amount of liquid and place it in a steel basin. Observe it under natural light or light. The color of the liquid should be uniform and there should be no particles in the structure.

[0053] 5) Mixing: After the dissolved liquid is passed through a 2.00mm filter, it is fully mixed with raw milk in a mixing tank and then transferred to a buffer tank.

[0054] 6) Homogenization sterilization: Homogenization temperature 50-80°C, homogenization total pressure 140-180 bar (secondary pressure 30-60 bar). Sterilization conditions: 80-90°C / 15-30 seconds.

[0055] 7) Volume adjustment: Add raw milk to the mixed liquid and adjust the volume to the desired semi-finished product quality. If the mixture in step 5) has already met the production requirements of high-calcium milk, step 7) can be omitted.

[0056] 8) Ultra-high temperature sterilization by homogenization: homogenization temperature 60-90°C, homogenization total pressure 230 bar (secondary pressure 25 bar); sterilization conditions: 135-145°C / 2-20s.

[0057] 9) Aseptic addition: Add Nurica under aseptic conditions TM Lactase.

[0058] 10) Enzymolysis: Enzymolysis at 25-45°C for 2-5 hours.

[0059] 11) Inactivate enzyme: 80-90℃ / 15-30s.

[0060] Example 2

[0061] The formula of high calcium milk in this embodiment is: 994.72 parts by weight of raw milk, 4 parts by weight of milk mineral salt, 0.26 parts by weight of gellan gum, 0.2 parts by weight of citrus fiber, 0.1 parts by weight of sodium tripolyphosphate, 0.4 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0062] In this embodiment, the mass ratio of raw milk, milk mineral salt, stabilizer and phosphate is 994.72:4:0.46:0.5.

[0063] The difference between the preparation method of this embodiment and that of Example 1 is:

[0064] The fat content of the raw milk used in this embodiment is 3.6 g / 100 g.

[0065] Step 3) Chemical processing: 70 times the total mass of the premix obtained in step 2) is added to the chemical processing tank, ensuring that the raw milk does not fall below the minimum stirring level. When the temperature is raised to 55°C, the premixed milk mineral salts and stabilizer are added from the high-speed shear port and stirred for 10 minutes. Then, the premixed phosphate and vitamin D3 are added and stirred for 10 minutes. The temperature is continued to be raised to 90°C and stirred for 30 minutes to ensure that all the raw materials are fully dissolved.

[0066] Step 8) The total homogenization pressure used for ultra-high temperature sterilization is 240 bar (secondary pressure 60 bar).

[0067] Example 3

[0068] The formula of high calcium milk in this embodiment is: 994.55 parts by weight of raw milk, 4.3 parts by weight of milk mineral salt, 0.1 parts by weight of carrageenan, 0.23 parts by weight of gellan gum, 0.2 parts by weight of sodium tripolyphosphate, 0.3 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0069] In this embodiment, the mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 994.55:4.3:0.33:0.5.

[0070] The difference between the preparation method of this embodiment and that of Example 1 is:

[0071] The fat content of the raw milk used in this embodiment is: 3.7g / 100g.

[0072] Step 3) Chemical processing: 90 times the total mass of the premix obtained in step 2) is added to the chemical processing tank, ensuring that the raw milk does not fall below the minimum stirring level. When the temperature is raised to 40°C, the premixed milk mineral salts and stabilizer are added from the high-speed shear port and stirred for 8 minutes. Then, the premixed phosphate and vitamin D3 are added and stirred for 8 minutes. The temperature is continued to be raised to 80°C and stirred for 20 minutes to ensure that all the raw materials are fully dissolved.

[0073] Step 8) The total homogenization pressure used for ultra-high temperature sterilization is 250 bar (secondary pressure 30 bar).

[0074] Example 4

[0075] The formula of high calcium milk in this embodiment is: 993.99 parts by weight of raw milk, 4.3 parts by weight of milk mineral salt, 0.2 parts by weight of carrageenan, 0.29 parts by weight of gellan gum, 0.4 parts by weight of citrus fiber, 0.3 parts by weight of sodium tripolyphosphate, 0.2 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0076] In this embodiment, the mass ratio of raw milk, milk mineral salts, stabilizer, and phosphate is 993.99:4.3:0.89:0.5. In the stabilizer, the mass ratio of carrageenan, gellan gum, and citrus fiber is 0.2:0.29:0.4.

[0077] The difference between the preparation method of this embodiment and that of Example 1 is:

[0078] The fat content of the raw milk used in this embodiment is: 3.8g / 100g.

[0079] Step 3) Chemical processing: 110 times the total mass of the premix obtained in step 2) is added to the chemical processing tank, ensuring that the raw milk does not fall below the minimum stirring level. When the temperature is raised to 40°C, the premixed milk mineral salts and stabilizer are added from the high-speed shear port and stirred for 8 minutes. Then, the premixed phosphate and vitamin D3 are added and stirred for 8 minutes. The temperature is continued to be raised to 80°C and stirred for 20 minutes to ensure that all the raw materials are fully dissolved.

[0080] Step 8) The total homogenization pressure used for ultra-high temperature sterilization is 260 bar (secondary pressure 50 bar).

[0081] Example 5

[0082] The formula of high calcium milk in this embodiment is: 993.46 parts by weight of raw milk, 4.6 parts by weight of milk mineral salt, 0.2 parts by weight of carrageenan, 0.32 parts by weight of gellan gum, 0.6 parts by weight of citrus fiber, 0.4 parts by weight of sodium tripolyphosphate, 0.1 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0083] In this embodiment, the mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 993.46:4.6:1.12:0.5; in the stabilizer, the mass ratio of carrageenan, gellan gum and citrus fiber is 0.2:0.32:0.6.

[0084] The preparation method of this embodiment is the same as that of Example 4.

[0085] Example 6

[0086] The formula of high calcium milk in this embodiment is: 993.115 parts by weight of raw milk, 4.6 parts by weight of milk mineral salt, 0.3 parts by weight of carrageenan, 0.35 parts by weight of gellan gum, 0.8 parts by weight of citrus fiber, 0.5 parts by weight of sodium tripolyphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.035 parts by weight.

[0087] In this embodiment, the mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 993.115:4.6:1.45:0.5; in the stabilizer, the mass ratio of carrageenan, gellan gum and citrus fiber is 0.3:0.35:0.8.

[0088] The preparation method of this embodiment is the same as that of Example 4.

[0089] Comparative Example 1

[0090] In this comparative example, the amount of milk mineral salt is reduced, and the formula of high calcium milk is: 995.18 parts by weight of raw milk, 3 parts by weight of milk mineral salt, 0.2 parts by weight of carrageenan, 0.5 parts by weight of citrus fiber, 0.8 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0091] The mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 995.18:3:0.7:0.8.

[0092] The preparation method is the same as that of Example 4.

[0093] Comparative Example 2

[0094] The formula of this comparative example is compared with that of Example 4, in which the amount of carrageenan is increased; the formula of high calcium milk is: 993.39 parts by weight of raw milk, 4.3 parts by weight of milk mineral salt, 0.8 parts by weight of carrageenan, 0.29 parts by weight of gellan gum, 0.4 parts by weight of citrus fiber, 0.3 parts by weight of sodium tripolyphosphate, 0.2 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0095] The mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 993.39:4.3:1.49:0.5; the mass ratio of carrageenan, gellan gum and citrus fiber is 0.8:0.29:0.4.

[0096] The preparation method is the same as that of Example 4.

[0097] Comparative Example 3

[0098] Compared with Example 4, the formula of this comparative example reduces the amount of gellan gum: 994.12 parts by weight of raw milk, 4.3 parts by weight of milk mineral salt, 0.2 parts by weight of carrageenan, 0.16 parts by weight of gellan gum, 0.4 parts by weight of citrus fiber, 0.3 parts by weight of sodium tripolyphosphate, 0.2 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0099] The mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 994.12:4.3:0.76:0.5. The mass ratio of carrageenan, gellan gum and citrus fiber is 0.2:0.16:0.4.

[0100] The preparation method is the same as that of Example 4.

[0101] Comparative Example 4

[0102] Compared with Example 4, the formula of this comparative example increases the amount of citrus fiber: 993.19 parts by weight of raw milk, 4.3 parts by weight of milk mineral salt, 0.2 parts by weight of carrageenan, 0.29 parts by weight of gellan gum, 1.2 parts by weight of citrus fiber, 0.3 parts by weight of sodium tripolyphosphate, 0.2 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0103] The mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 993.19:4.3:1.69:0.5. The mass ratio of carrageenan, gellan gum and citrus fiber is 0.2:0.29:1.2.

[0104] The preparation method is the same as that of Example 4.

[0105] Comparative Example 5

[0106] Compared with Example 4, the formula of this comparative example omits phosphate: 994.49 parts by weight of raw milk, 4.3 parts by weight of milk mineral salt, 0.2 parts by weight of carrageenan, 0.29 parts by weight of gellan gum, 0.4 parts by weight of citrus fiber, 0.5 parts by weight of Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0107] The mass ratio of raw milk, milk mineral salts and stabilizer is 994.49:4.3:0.89. The mass ratio of carrageenan, gellan gum and citrus fiber is 0.2:0.29:0.4.

[0108] The preparation method is the same as that of Example 4.

[0109] Comparative Example 6

[0110] Compared with Example 4, the formula of this comparative example increases the amount of phosphate: 992.89 parts by weight of raw milk, 4.3 parts by weight of milk mineral salt, 0.2 parts by weight of carrageenan, 0.29 parts by weight of gellan gum, 0.4 parts by weight of citrus fiber, 0.8 parts by weight of sodium tripolyphosphate, 0.8 parts by weight of sodium hexametaphosphate, Nurica TM Lactase 0.3 parts by weight and vitamin D3 0.02 parts by weight.

[0111] The mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 992.89:4.3:0.89:1.6. The mass ratio of carrageenan, gellan gum and citrus fiber is 0.2:0.29:0.4.

[0112] The preparation method is the same as that of Example 4.

[0113] Comparative Example 7

[0114] Compared with Example 4, the formula of this comparative example uses ordinary lactase instead of Nurica TM Lactase: 993.29 parts by weight of raw cow's milk, 4.3 parts by weight of milk mineral salts, 0.2 parts by weight of carrageenan, 0.29 parts by weight of gellan gum, 0.4 parts by weight of citrus fiber, 0.3 parts by weight of sodium tripolyphosphate, 0.2 parts by weight of sodium hexametaphosphate, 0.02 parts by weight of vitamin D3 and 1 part by weight of ordinary lactase.

[0115] The mass ratio of raw milk, milk mineral salts, stabilizer and phosphate is 993.99:4.3:0.89:0.5. The mass ratio of carrageenan, gellan gum and citrus fiber is 0.2:0.29:0.4.

[0116] The preparation method is the same as that of Example 4.

[0117] Comparative Examples 8-13

[0118] The formulations of Comparative Examples 8-13 are the same as those of Example 3.

[0119] The preparation method of Comparative Example 8 differs from that of Example 3 in that: the total homogenization pressure used in step 8) homogenization and ultrahigh temperature sterilization is 190 bar.

[0120] The preparation method of Comparative Example 9 differs from that of Example 3 in that the total homogenization pressure used in step 8) homogenization and ultrahigh temperature sterilization is 280 bar.

[0121] The difference between the preparation method of Comparative Example 10 and Example 3 is that the order of adding phosphate and stabilizer is different.

[0122] Specifically, in step 2), milk mineral salts and phosphates are premixed; stabilizers and vitamin D3 are premixed; in step 3), the premixed milk mineral salts and phosphates are first added and stirred, and then the premixed combined stabilizer and vitamin D3 are added and stirred to ensure that all the raw materials are fully dissolved.

[0123] The preparation method of Comparative Example 11 differs from that of Example 3 in that the fat content of the raw cow's milk used is 4.3 g / 100 g.

[0124] The difference between the preparation method of Comparative Example 12 and Example 3 is that the fat content of the raw cow's milk used is 3.4g / 100g.

[0125] The difference between the preparation method of Comparative Example 13 and Example 3 is that in step 3), the raw milk used in the chemical process is 20 times the total mass of the premix obtained in step 2).

[0126] Experimental Example 1 Milk Stability Test

[0127] The resulting high-calcium milk was allowed to stand at room temperature for 180 days. The milk was then slowly poured out of the bag. The samples were tested for fat floating thickness, bottom sedimentation, centrifugal sedimentation rate, average particle size, clarity index, and viscosity. The yellowness and whiteness of the milk obtained in Example 4 and Comparative Example 7 were also measured. The results are shown in Table 1.

[0128] Table 1 Milk stability test results

[0129] Experimental Example 2 Determination of calcium content in milk

[0130] The calcium content in milk was measured at the end of each month using flame atomic absorption spectrometry, method 1 of GB 5009.92-2016. The results are shown in Table 2. It should be noted that the density of the high-calcium milk in the present invention is between 1.030 and 1.040 g / mL. When tested using flame atomic absorption spectrometry, the calcium content is measured in mg / 100 g. When converted to liquid high-calcium milk, the calcium content per 100 mL of high-calcium milk is slightly higher than the data in Table 2.

[0131] Table 2 Determination of calcium content in milk

[0132] From the results in Tables 1 and 2, it can be seen that compared with Example 4, Comparative Example 1 cannot meet the double calcium requirement due to the lower content of milk mineral salts used and the lower calcium content, and its original calcium content is significantly lower than that of Example 4.

[0133] In Comparative Example 2, a large amount of carrageenan was added, resulting in an extremely unstable gel system. As shown in Table 1, the viscosity of the high-calcium milk obtained in Comparative Example 2 was 12.69 cp, which was significantly higher than 5.20 cp in Example 4. The fineness was very poor and the milk was rather mushy.

[0134] In Comparative Example 3, the amount of gellan gum added was relatively small, and the added milk mineral salts could not be completely suspended. Therefore, in Comparative Example 3, the initial calcium content was 201 mg / 100 mg, but the calcium content dropped to 176 mg / 100 mg at the end of the sixth month, indicating a significant decrease in the calcium content of the product. Furthermore, the centrifugal sedimentation rate of the product obtained in Comparative Example 3 was 3.28%, and the average particle size was 2.35 μm, significantly higher than those in the examples.

[0135] In Comparative Example 4, the amount of citrus fiber added was too much, causing the citrus fiber to precipitate itself. Therefore, the average particle size of Comparative Example 4 was 8.79 μm, which was significantly higher than 0.6 μm of Example 4.

[0136] In Comparative Example 5, no phosphate was added, which could not chelate the excessive exogenous calcium, resulting in a system with more calcium ions and instability, which was specifically reflected in the high centrifugal sedimentation rate of the product and more sediment at the bottom.

[0137] In Comparative Example 6, excessive addition of phosphate resulted in a salty overall taste and a sharp drop in the pH value of milk. The centrifugal sedimentation rate was 1.98%, which was significantly higher than that in the examples.

[0138] The results in Table 1-2 show that the high-calcium milk prepared in the embodiments of the present invention can achieve a product calcium content of ≥200 mg / 100 mL, and the calcium content in the high-calcium milk is stable during the shelf life.

[0139] Experimental Example 3 Consumer Testing

[0140] Fifty ordinary consumers were selected to taste test the aforementioned beverages, assigning a comprehensive score based on milky flavor, fullness, smoothness, and texture, with a maximum score of 10. Higher scores for milky flavor, fullness, smoothness, and texture indicate better taste. The results are shown in Table 3.

[0141] Table 3 Consumer taste test results

[0142] In Comparative Example 7, ordinary lactase was used to replace Nurica TM Although the dosage of ordinary lactase was increased, the milk obtained in Comparative Example 7 had a higher reducing sugar content due to the high content of reducing sugars produced by the hydrolysis of lactose by ordinary lactase, which easily accelerated browning during heating or storage. As can be seen from Table 1, the milk obtained in Comparative Example 7 had a lower whiteness and a higher yellowness than the milk in the examples, resulting in easier sensory observation of fat floating.

[0143] Compared with Example 3, the homogenization pressure in Comparative Example 8 is relatively low, and the fat particles cannot be divided into smaller particles to a greater extent, and are easily aggregated and floated. Its centrifugal sedimentation rate, average particle size and clarification index are significantly higher than those in the example.

[0144] In Comparative Example 9, the homogenization pressure is relatively high, which easily destroys the fat globule membrane and releases fat, resulting in system instability and easy floating of fat. The centrifugal sedimentation rate, average particle size and clarification index are significantly higher than those in the embodiment.

[0145] In Comparative Example 10, due to the different order of adding phosphate and stabilizer, the thickness of the fat floating on the surface increased, the sedimentation at the bottom increased, and the centrifugal sedimentation rate increased.

[0146] In Comparative Example 11, since the fat content of the raw cow milk used was too high, fat was easily caused to float, and the centrifugal sedimentation rate, average particle size and clarification index were significantly higher than those in the embodiment.

[0147] In Comparative Example 12, since the fat content of the raw cow's milk used is too low, the milk flavor is weak and is not easily accepted by consumers.

[0148] In Comparative Example 13, the dissolution ratio is too low, so that the stabilizer cannot be completely dissolved in the milk, resulting in decreased thickening and suspension capabilities, which in turn causes the centrifugal sedimentation rate, average particle size and clarification index to be significantly higher than those in the examples, increased precipitation and low calcium content.

[0149] The results of comparative examples 7-13 show that the present invention can TM Lactase, adjustment of raw milk fat content, and optimization of the preparation process solved the problem of fat floating in high-calcium milk products.

[0150] 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 various embodiments of the present invention.

Claims

1. A high-calcium milk, characterized in that, In the high-calcium milk, the mass ratio of raw milk, milk mineral salts, stabilizer, and phosphate is (992 - 995):(4 - 5):(0.26 - 1.7):(0.5 - 1); in the stabilizer, the mass ratio of carrageenan, gellan gum, and citrus fiber is (0 - 0.3):(0.23 - 0.4):(0 - 1).

2. The high-calcium milk according to claim 1, characterized in that, In the high-calcium milk, the phosphate includes one or both of sodium tripolyphosphate and sodium hexametaphosphate.

3. The high-calcium milk according to any one of claims 1-2, characterized in that, The fat content of the raw milk is 3.5 - 4.0 g / 100 g.

4. The high-calcium milk according to any one of claims 1 to 3, characterized in that, In the high-calcium milk, lactase is also included.

5. The high-calcium milk according to any one of claims 1 to 4, characterized in that, In the high-calcium milk, there are 992 - 995 parts by weight of raw milk, 3 - 5 parts by weight of milk mineral salts, 0.1 - 0.3 parts by weight of carrageenan, 0.23 - 0.40 parts by weight of gellan gum, 0.2 - 1.0 parts by weight of citrus fiber, 0.1 - 0.5 parts by weight of sodium tripolyphosphate, 0.1 - 0.5 parts by weight of sodium hexametaphosphate, 0.3 parts by weight of lactase, and 0.010 - 0.035 parts by weight of vitamin D3.

6. The high-calcium milk according to any one of claims 1-5, characterized in that, In the high-calcium milk, there are 992 - 995 parts by weight of raw milk, 4.0 - 4.6 parts by weight of milk mineral salts, 0.1 - 0.3 parts by weight of carrageenan, 0.23 - 0.35 parts by weight of gellan gum, 0.2 - 0.8 parts by weight of citrus fiber, 0.1 - 0.5 parts by weight of sodium tripolyphosphate, 0.1 - 0.5 parts by weight of sodium hexametaphosphate, 0.3 parts by weight of lactase, and 0.010 - 0.035 parts by weight of vitamin D3.

7. The preparation method of the high-calcium milk according to any one of claims 1-6, characterized in that, After stirring the milk mineral salts and the stabilizer in the raw milk at 35 - 55 °C for 3 - 10 min, add the phosphate and vitamin D3, stir for 3 - 10 min, continue to heat up to 70 - 90 °C, and continuously stir for 10 - 30 min to complete the material melting.

8. The preparation method of the high-calcium milk according to claim 7, wherein, It includes: Premixing, material melting, volume fixing, sterilization and homogenization, secondary sterilization and homogenization, enzymatic hydrolysis, and enzyme inactivation.

9. The method for preparing high-calcium milk according to claim 8, characterized in that, During the material melting, the weight of the raw milk is 30 - 160 times the mass of the milk mineral salts, stabilizer, phosphate, and vitamin D3. The total pressure of the secondary sterilization and homogenization is 230 - 260 bar, and the secondary pressure is 25 - 60 bar.

10. The method for preparing high-calcium milk according to any one of claims 7-9, characterized in that, It includes: (1) Pretreat the raw milk to obtain raw milk; (2) Premix the milk mineral salts and the stabilizer; Premix the phosphate and vitamin D3; (3) After heating up the raw milk obtained in step (1), add the premixed milk mineral salts and stabilizer in step (2), and the premixed phosphate and vitamin D3 for material melting to obtain a mixed liquid; (4) Add the remaining raw milk to the mixed liquid obtained in step (3), perform sterilization and homogenization and secondary sterilization and homogenization to obtain a semi-finished high-calcium milk; (5) Add lactase to the semi-finished high-calcium milk obtained in step (4) for enzymatic hydrolysis, and then inactivate the enzyme to obtain the high-calcium milk.