Whole-grain super-concentrated nutritional essence instant milk tea and preparation method thereof

Abstract

The invention discloses whole-grain super-concentrated nutritional essence instant milk tea and a preparation method thereof, and relates to the technical field of food processing. The preparation method sequentially comprises the following steps: mixing the whole grains and the nutritional food materials, and adding purified water for soaking; performing supercritical fluid extraction and filtration to obtain a mixed extract; mixing the mixed extract with the crushed tea substrate, and then adding a compound enzyme for enzymolysis; performing microwave-assisted extraction, and filtering to obtain a microwave-assisted extract; performing high-pressure homogenization treatment on the microwave-assisted extract twice; carrying out microencapsulation, using Arabic gum as a wall material, forming microcapsules by using a microencapsulation technology, and enabling the particle size of the microcapsules to be 1-5 [mu] m; and drying the microcapsules, and mixing the microcapsules with a milk base to obtain the whole-grain super-concentrated nutritional essence instant milk tea. The milk tea prepared by the preparation method disclosed by the invention can well retain nutritional ingredients in whole grains and nutritional food materials, and has good solubility, good stability and long shelf life.

Description

Technical Field

[0001] The invention relates to the technical field of food processing, and in particular to whole-grain super-concentrated nutritional essence instant milk tea and a preparation method thereof. Background Art

[0002] In the field of food science, whole grains such as oats, brown rice, coix seeds, black rice, quinoa, etc., have attracted much attention because they retain the three parts of the grain: the germ, endosperm and bran, and are rich in various nutrients. Nutritious ingredients such as spirulina, wolfberry, maca, etc. are also valued because they are rich in antioxidants, vitamins and other beneficial ingredients. Traditional processing methods such as grinding, boiling and other simple treatments can no longer meet modern needs. Existing processing methods also have problems such as low extraction efficiency and easy damage to nutrients. In addition, due to the limitations of existing processing methods, whole grains and nutritious ingredients still have problems such as poor solubility when made into brewed beverages. Summary of the invention

[0003] In order to solve the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a whole grain super concentrated nutritional essence instant milk tea and a preparation method thereof. The present invention can retain the nutritional components in whole grains and nutritious ingredients, and also has good solubility and taste.

[0004] The present invention provides the following technical solutions:

[0005] The present invention provides a method for preparing whole grain super concentrated nutritional essence instant milk tea, comprising the following steps:

[0006] S1: Grind the whole grains and the nutritious ingredients and mix them evenly, then add purified water at a material-liquid ratio of 1:(3-7) and soak for 3-5 hours; then perform supercritical fluid extraction, filter, and obtain a mixed extract; the nutritious ingredients include spirulina, wolfberry, and maca;

[0007] S2: adding a composite enzyme to the mixed extract for enzymolysis; the composite enzyme comprises cellulase and protease;

[0008] S3: mixing the sample treated in step S2 with an ethanol solution having a mass concentration of 70% at a volume ratio of 1:10, performing microwave-assisted extraction, and filtering to obtain a microwave-assisted extract;

[0009] S4: subjecting the microwave-assisted extract to two high-pressure homogenization treatments to a particle size of 80-100 mesh;

[0010] S5: microencapsulating the sample after high-pressure homogenization in step S4, using gum arabic as the wall material, mixing the sample with gum arabic in a ratio of 1:(2-5), and then using microencapsulation technology to form microcapsules, wherein the particle size of the microcapsules is 1-5 μm; drying the microcapsules, and then mixing them with crushed tea base and milk base to obtain whole grain ultra-concentrated nutritional essence instant milk tea.

[0011] Preferably, the supercritical fluid extraction is supercritical carbon dioxide extraction, and supercritical carbon dioxide is used to extract these raw materials to protect heat-sensitive components from being destroyed and to retain their nutritional value to the maximum extent.

[0012] Preferably, in the step S4, an additive may be added after the drying process, and the additive is selected from at least one of a sweetener and a probiotic freeze-dried powder.

[0013] Preferably, the natural sweetener is selected from one of steviol glycosides, mogroside and erythritol.

[0014] Preferably, the tea base is black tea or green tea.

[0015] Furthermore, in step S2, the conditions for enzymatic hydrolysis are: pH value of 5.5-6.5, temperature of 45-55°C, and enzymatic hydrolysis time of 0.5-2h. Decomposing macromolecular substances by the action of specific enzymes can improve the absorbability and solubility of the extract, making it easier to be absorbed by the human body.

[0016] Furthermore, in the step S2, after the enzymatic hydrolysis is completed, the temperature needs to be maintained at 80-90°C for more than 10 minutes until the activity of the enzyme is terminated; then the enzyme residue is removed and the extract after enzymatic hydrolysis is collected.

[0017] Furthermore, the whole grains include the following components in proportions by mass: 10-20 parts of oats, 5-10 parts of brown rice, 5-10 parts of coix seeds, 5-10 parts of black rice and 5-10 parts of quinoa.

[0018] Furthermore, the mass ratio of spirulina, wolfberry and maca is (3-5): (3-5): (2-5).

[0019] Furthermore, the mass ratio of the whole grains, nutritious ingredients, tea base, milk base and additives is (23-45): (15-30): (10-20): 5: (1-5).

[0020] Preferably, the whole grains and nutritious ingredients have a particle size of 5-10 μm after crushing.

[0021] Furthermore, the supercritical fluid extraction is performed at least three times; the pressure of the supercritical fluid extraction is 250-350 bar, the temperature is 30-35° C., and the extraction time is 1.5-2.5 h.

[0022] Furthermore, the microwave-assisted extraction utilizes microwave energy to quickly and efficiently promote the release of effective ingredients, improve extraction efficiency, and ensure the quality of the extract. The microwave-assisted extraction is performed at least three times.

[0023] Furthermore, the added amount of the complex enzyme is 0.1%-1% of the total mass of the raw materials; the mass ratio of the cellulase and the protease is (2-5):(1-2).

[0024] Furthermore, the pressure of the high temperature homogenization treatment is 100-300 bar.

[0025] Furthermore, the drying process specifically comprises the following steps:

[0026] The microcapsules are spray dried at an air inlet temperature of 180±5°C and an air outlet temperature of 80±5°C; the spray dried sample is pre-frozen at -50±2.5°C for 3-4 hours, and then the vacuum degree is adjusted to 0.1±0.02mbar, and freeze dried until the moisture content is less than 2%. The spray drying can improve the solubility and stability of the milk tea; the freeze drying can retain the nutrients and active ingredients to the maximum extent.

[0027] Preferably, after spray drying, the average particle size of the sample powder is 20-50 μm.

[0028] The present invention also provides whole grain super concentrated nutritional essence instant milk tea prepared by the preparation method of the whole grain super concentrated nutritional essence instant milk tea.

[0029] The present invention has the following technical effects:

[0030] The present invention adopts supercritical fluid extraction, enzymatic hydrolysis technology and microwave-assisted extraction to extract essence ingredients from whole grains and nutritious ingredients. Combined with microencapsulation and drying technology, the prepared milk tea is easy to dissolve, has a rich taste and high nutritional value. Supercritical fluid extraction is used to extract effective ingredients and protect heat-sensitive ingredients; enzymatic hydrolysis technology is used to decompose macromolecules to improve absorbency; microwave-assisted extraction is used to accelerate the release of effective ingredients and improve extraction efficiency; high-pressure homogenization technology is used to refine particles to improve solubility and taste; microencapsulation is used to protect active ingredients and improve stability and shelf life. DETAILED DESCRIPTION

[0031] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solution of the present invention. 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.

[0032] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0033] In order to more fully understand the technical content of the present invention, the technical solution of the present invention is further introduced and illustrated in conjunction with specific embodiments below.

[0034] Specifically, the pretreatment of raw materials is as follows:

[0035] (1) Pretreatment of whole grains

[0036] Washing: Wash the whole grains under running water for 5-10 minutes to remove dust and impurities attached to the surface.

[0037] Soaking: Soak the washed whole grains at room temperature for 3-5 hours to allow them to fully absorb water and swell.

[0038] Steaming: Put the soaked whole grains into a pressure cooker and steam for 25-35 minutes to soften them for subsequent processing.

[0039] (2) Pretreatment of nutritious ingredients

[0040] Cleaning: Use tap water to clean spirulina, wolfberry and maca for 5-10 minutes to remove dust and impurities attached to the surface.

[0041] Drying: Air dry the cleaned nutritious ingredients or use drying equipment to dry them, ensuring that their moisture content is below 10% to avoid sticking during crushing.

[0042] Example 1

[0043] A method for preparing whole grain super concentrated nutritional essence instant milk tea comprises the following steps:

[0044] S1: Raw material selection;

[0045] Select the following components by weight:

[0046] Whole grains: 20 portions of oats, 5 portions of brown rice, 5 portions of coix seeds, 5 portions of black rice, 5 portions of quinoa;

[0047] Nutritional ingredients: 3 parts of spirulina, 3 parts of wolfberry, 2 parts of maca;

[0048] 10 parts of black tea base;

[0049] 5 servings of milk powder;

[0050] Natural sweetener 5 servings.

[0051] S2: Supercritical fluid extraction: Whole grains and nutritious ingredients are extracted with supercritical carbon dioxide at a pressure of 300 bar and a temperature of 31°C for 2 hours. Three supercritical fluid extractions are performed, and the extracts are collected and the residues are filtered after each extraction. The three extracts are mixed to obtain a supercritical fluid extract.

[0052] S3: Enzymatic hydrolysis: add 0.144 parts of cellulase and 0.096 parts of protease to the supercritical fluid extract, and perform enzymatic hydrolysis at pH 5.5 and temperature 50°C for 1 hour. After the enzymatic hydrolysis is completed, heat to 85°C and maintain for 10 minutes to terminate the activity of the enzyme. Remove the enzyme residue by centrifugation or filtration, and collect the extract after enzymatic hydrolysis.

[0053] S4: Microwave-assisted extraction; use a microwave extraction device, set the power to 700W, the time to 5 minutes, the temperature during the extraction process does not exceed 70°C, and use an ethanol solution with a mass concentration of 70% as the solvent. The enzymatic extract and the ethanol solution are mixed and extracted at a volume ratio of 10:1. Microwave-assisted extraction 3 times: After the first extraction is completed, the extract is collected and the residue is filtered; the second extraction uses the residue of the first extraction as a sample and repeats the first operation; the third extraction uses the residue of the second extraction as a sample, and the operation is repeated so that the content of the active ingredient in the extract no longer increases significantly. The extracts after the three extractions are mixed evenly to obtain a microwave-assisted extract.

[0054] S5: High-pressure homogenization: Add the microwave-assisted extract to the high-pressure homogenizer, set the pressure of the high-pressure homogenizer to 200 bar, and perform two homogenization processes to make the particle size of the extract after homogenization reach 80-100 mesh.

[0055] S6: Microencapsulation; using gum arabic as the wall material, the homogenized extract and gum arabic are mixed in a ratio of 1:3, and then microencapsulation technology is used to form microcapsules, and the particle size of the microcapsules is controlled between 1-5 μm.

[0056] S7: spray drying: spray drying the microcapsules at an air inlet temperature of 180° C. and an air outlet temperature of 80° C. The powder particle size distribution after spray drying is 20-50 μm.

[0057] S8: Freeze drying: precool the spray-dried powder at -50°C for 3 hours, adjust the vacuum degree to 0.1 mbar, and continue freeze drying for 24 hours to maintain the original nutrient content and make the moisture content less than 2%. Finally, mix the freeze-dried powder with milk powder and natural sweetener to obtain whole grain super concentrated nutrient essence instant milk tea.

[0058] Example 2

[0059] A method for preparing whole grain super concentrated nutritional essence instant milk tea comprises the following steps:

[0060] S1: Raw material selection;

[0061] Select the following components by weight:

[0062] Whole grains: 10 portions of oats, 6 portions of brown rice, 8 portions of coix seeds, 10 portions of black rice, 6 portions of quinoa;

[0063] Nutritional ingredients: 4 parts of spirulina, 5 parts of wolfberry, 3 parts of maca;

[0064] 16 parts of black tea base;

[0065] 5 servings of milk powder.

[0066] S2: Supercritical fluid extraction: Whole grains and nutritious ingredients were extracted with supercritical carbon dioxide at a pressure of 250 bar and a temperature of 30°C for 2.5 hours. Four supercritical fluid extractions were performed, and the extracts were collected and the residues were filtered after each extraction. The four extracts were mixed to obtain a supercritical fluid extract.

[0067] S3: Enzymatic hydrolysis: add 0.284 parts of cellulase and 0.142 parts of protease to the supercritical fluid extract, and perform enzymatic hydrolysis for 1.5 hours at a pH of 6.5 and a temperature of 45°C. After the enzymatic hydrolysis is completed, heat to 80°C and maintain for 10 minutes to terminate the activity of the enzyme. Remove the enzyme residue by centrifugation or filtration, and collect the extract after enzymatic hydrolysis; the composite enzyme includes cellulase and protease in a mass ratio of 6:4.

[0068] S4: Microwave-assisted extraction; use a microwave extraction device, set the power to 650W, the time to 5 minutes, the temperature during the extraction process is 70°C, and use an ethanol solution with a mass concentration of 70% as the solvent. The enzymatic extract and the ethanol solution are mixed and extracted at a volume ratio of 10:1. Microwave-assisted extraction 3 times: After the first extraction is completed, the extract is collected and the residue is filtered; the second extraction uses the residue of the first extraction as a sample and repeats the first operation; the third extraction uses the residue of the second extraction as a sample, and repeats the operation so that the content of the active ingredient in the extract no longer increases significantly. The extracts after the three extractions are mixed evenly to obtain a microwave-assisted extract.

[0069] S5: High-pressure homogenization: Add the microwave-assisted extract to the high-pressure homogenizer, set the pressure of the high-pressure homogenizer to 200 bar, and perform two homogenization processes to make the particle size of the extract after homogenization reach 80-100 mesh.

[0070] S6: Microencapsulation; using gum arabic as the wall material, the homogenized extract and gum arabic are mixed in a ratio of 1:2, and then microencapsulation technology is used to form microcapsules, and the particle size of the microcapsules is controlled between 1-5 μm.

[0071] S7: spray drying: spray drying the microcapsules at an air inlet temperature of 185° C. and an air outlet temperature of 75° C. The powder particle size distribution after spray drying is 20-50 μm.

[0072] S8: Freeze drying: precool the spray-dried powder at -52.5°C for 3.5 hours, adjust the vacuum degree to 0.12 mbar, and continue freeze drying for 24 hours to maintain the original nutrient content and make the moisture content less than 2%. Finally, mix the freeze-dried powder with milk powder to obtain whole grain super concentrated nutrient essence instant milk tea.

[0073] Example 3

[0074] A method for preparing whole grain super concentrated nutritional essence instant milk tea comprises the following steps:

[0075] S1: Raw material selection;

[0076] Select the following components by weight:

[0077] Whole grains: 10 portions of oats, 5 portions of brown rice, 5 portions of coix seeds, 5 portions of black rice, 5 portions of quinoa;

[0078] Nutritional ingredients: 3 parts of spirulina, 4 parts of wolfberry, 5 parts of maca;

[0079] 10 parts of black tea base;

[0080] 5 servings of milk powder;

[0081] 2 portions of probiotic freeze-dried powder.

[0082] S2: Supercritical fluid extraction: Whole grains and nutritious ingredients are extracted using supercritical carbon dioxide at a pressure of 350 bar and a temperature of 31°C for 1.5 hours. Three supercritical fluid extractions are performed, and the extracts are collected and the residues are filtered after each extraction. The three extracts are mixed to obtain a supercritical fluid extract.

[0083] S3: Enzymatic hydrolysis: 0.421 parts of cellulase and 0.169 parts of protease were added to the supercritical fluid extract, and the enzymatic hydrolysis was carried out at a pH of 5.5 and a temperature of 50°C for 1 hour. After the enzymatic hydrolysis was completed, the extract was heated to 85°C and maintained for 10 minutes to terminate the activity of the enzyme. The enzyme residue was removed by centrifugation or filtration, and the extract after enzymatic hydrolysis was collected.

[0084] S4: Microwave-assisted extraction; use a microwave extraction device, set the power to 750W, the time to 5 minutes, the temperature during the extraction process is 70°C, and use an ethanol solution with a mass concentration of 70% as the solvent. The enzymatic extract and the ethanol solution are mixed and extracted at a volume ratio of 10:1. Microwave-assisted extraction 3 times: After the first extraction is completed, the extract is collected and the residue is filtered; the second extraction uses the residue of the first extraction as a sample and repeats the first operation; the third extraction uses the residue of the second extraction as a sample, and the operation is repeated so that the content of the active ingredient in the extract no longer increases significantly. The extracts after the three extractions are mixed evenly to obtain a microwave-assisted extract.

[0085] S5: High-pressure homogenization: Add the microwave-assisted extract to the high-pressure homogenizer, set the pressure of the high-pressure homogenizer to 200 bar, and perform two homogenization processes to make the particle size of the extract after homogenization reach 80-100 mesh.

[0086] S6: Microencapsulation; using gum arabic as the wall material, the homogenized extract and gum arabic are mixed in a ratio of 1:5, and then microencapsulation technology is used to form microcapsules, and the particle size of the microcapsules is controlled between 1-5 μm.

[0087] S7: spray drying: spray drying the microcapsules at an air inlet temperature of 180° C. and an air outlet temperature of 85° C. The particle size distribution of the powder after spray drying is 20-50 μm.

[0088] S8: Freeze drying: precool the spray-dried powder at -47.5°C for 4 hours, adjust the vacuum degree to 0.08 mbar, and continue freeze drying for 24 hours to maintain the original nutrient content and make the moisture content less than 2%. Finally, mix the freeze-dried powder, the crushed black tea base, milk powder and probiotic freeze-dried powder evenly to obtain whole grain super concentrated nutrient essence instant milk tea.

[0089] Example 4

[0090] A method for preparing whole grain super concentrated nutritional essence instant milk tea comprises the following steps:

[0091] S1: Raw material selection;

[0092] Select the following components by weight:

[0093] Whole grains: 20 portions of oats, 10 portions of brown rice, 10 portions of coix seeds, 10 portions of black rice, 10 portions of quinoa;

[0094] Nutritional ingredients: 5 parts of spirulina, 5 parts of wolfberry, 2 parts of maca;

[0095] Green tea base 20 parts;

[0096] 5 servings of milk powder;

[0097] 3 parts natural sweetener;

[0098] 2 portions of probiotic freeze-dried powder.

[0099] S2: Supercritical fluid extraction: Whole grains and nutritious ingredients are extracted with supercritical carbon dioxide at a pressure of 300 bar and a temperature of 35°C for 2 hours. Three supercritical fluid extractions are performed, and the extracts are collected and the residues are filtered after each extraction. The three extracts are mixed to obtain a supercritical fluid extract.

[0100] S3: Enzymatic hydrolysis: add 0.126 parts of cellulase and 0.084 parts of protease to the supercritical fluid extract, and perform enzymatic hydrolysis at pH 5.5 and temperature 50°C for 1 hour. After the enzymatic hydrolysis is completed, heat to 90°C and maintain for 10 minutes to terminate the activity of the enzyme. Remove the enzyme residue by centrifugation or filtration, and collect the extract after enzymatic hydrolysis.

[0101] S4: Microwave-assisted extraction; use a microwave extraction device, set the power to 700W, the time to 5 minutes, the temperature during the extraction process is 68°C, and use an ethanol solution with a mass concentration of 70% as the solvent. The enzymatic extract and the ethanol solution are mixed and extracted at a volume ratio of 10:1. Microwave-assisted extraction 3 times: After the first extraction is completed, the extract is collected and the residue is filtered; the second extraction uses the residue of the first extraction as a sample and repeats the first operation; the third extraction uses the residue of the second extraction as a sample, and the operation is repeated so that the content of the active ingredient in the extract no longer increases significantly. The extracts after the three extractions are mixed evenly to obtain a microwave-assisted extract.

[0102] S5: High-pressure homogenization: Add the microwave-assisted extract to the high-pressure homogenizer, set the pressure of the high-pressure homogenizer to 200 bar, and perform two homogenization processes to make the particle size of the extract after homogenization reach 80-100 mesh.

[0103] S6: Microencapsulation; using gum arabic as the wall material, the homogenized extract and gum arabic are mixed in a ratio of 1:3, and then microencapsulation technology is used to form microcapsules, and the particle size of the microcapsules is controlled between 1-5 μm.

[0104] S7: spray drying: spray drying the microcapsules at an air inlet temperature of 175° C. and an air outlet temperature of 80° C. The powder particle size distribution after spray drying is 20-50 μm.

[0105] S8: Freeze drying: precool the spray-dried powder at -60°C for 3 hours, adjust the vacuum degree to 0.1 mbar, and continue freeze drying for 24 hours to maintain the original nutrient content and make the moisture content less than 2%. Finally, mix the freeze-dried powder, crushed green tea base, milk powder, natural sweetener and probiotic freeze-dried powder evenly to obtain whole grain super concentrated nutrient essence instant milk tea.

[0106] Example 5

[0107] A method for preparing whole grain super concentrated nutritional essence instant milk tea comprises the following steps:

[0108] S1: Raw material selection;

[0109] Select the following components by weight:

[0110] Whole grains: 20 portions of oats, 5 portions of brown rice, 5 portions of coix seeds, 10 portions of black rice, 5 portions of quinoa;

[0111] Nutritional ingredients: 3 parts of spirulina, 4 parts of wolfberry, 2 parts of maca;

[0112] 12 parts of black tea base;

[0113] 5 servings of milk powder;

[0114] Natural sweetener 5 servings.

[0115] S2: Supercritical fluid extraction: Whole grains and nutritious ingredients are extracted with supercritical carbon dioxide at a pressure of 300 bar and a temperature of 31°C for 2 hours. Three supercritical fluid extractions are performed, and the extracts are collected and the residues are filtered after each extraction. The three extracts are mixed to obtain a supercritical fluid extract.

[0116] S3: Enzymatic hydrolysis: add 0.365 parts of cellulase and 0.243 parts of protease to the supercritical fluid extract, and perform enzymatic hydrolysis at pH 5.5 and temperature 50°C for 1 hour. After the enzymatic hydrolysis is completed, heat to 85°C and maintain for 10 minutes to terminate the activity of the enzyme. Remove the enzyme residue by centrifugation or filtration, and collect the extract after enzymatic hydrolysis.

[0117] S4: Microwave-assisted extraction; use a microwave extraction device, set the power to 700W, the time to 5 minutes, the temperature during the extraction process does not exceed 70°C, and use an ethanol solution with a mass concentration of 70% as the solvent. The enzymatic extract and the ethanol solution are mixed and extracted at a volume ratio of 10:1. Microwave-assisted extraction 3 times: After the first extraction is completed, the extract is collected and the residue is filtered; the second extraction uses the residue of the first extraction as a sample and repeats the first operation; the third extraction uses the residue of the second extraction as a sample, and the operation is repeated so that the content of the active ingredient in the extract no longer increases significantly. The extracts after the three extractions are mixed evenly to obtain a microwave-assisted extract.

[0118] S5: High pressure homogenization: Add micro

[0119] The wave-assisted extraction was performed by setting the pressure of the high-pressure homogenizer to 200 bar and performing two homogenization processes. The particle size of the extract after homogenization reached 80-100 mesh.

[0120] S6: Microencapsulation; using gum arabic as the wall material, the homogenized extract and gum arabic are mixed in a ratio of 1:3, and then microencapsulation technology is used to form microcapsules, and the particle size of the microcapsules is controlled between 1-5 μm.

[0121] S7: spray drying: spray drying the microcapsules at an air inlet temperature of 180° C. and an air outlet temperature of 85° C. The particle size distribution of the powder after spray drying is 20-50 μm.

[0122] S8: Freeze drying: precool the spray-dried powder at -51°C for 3 hours, adjust the vacuum degree to 0.1 mbar, and continue freeze drying for 24 hours to maintain the original nutrient content and make the moisture content less than 2%. Finally, mix the freeze-dried powder, crushed black tea base, milk powder and natural sweetener evenly to obtain whole grain super concentrated nutrient essence instant milk tea.

[0123] To illustrate the technical effect of the present invention, the following test experiments were carried out on Examples 1-5.

[0124] (I) Solubility test

[0125] (1) Solubility test of the homogenized extracts of Examples 1-5

[0126] The solubility test method is as follows:

[0127] Weigh 1 g of each of the homogenized extract samples of Examples 1-5 as samples, and use a quantitative pipette to add 10 ml of distilled water to the container containing the sample, with a sample to solvent ratio of 1:10. Use a magnetic stirrer to stir the mixture at a medium speed for 5 minutes. After stopping stirring, let the mixture stand for 10 minutes and record the state of the mixture. Subsequently, use a microscope to observe the particle distribution to confirm whether the particles are evenly dispersed.

[0128] The test results are shown in Table 1 below:

[0129] Table 1 Solubility test results of the extracts after homogenization of Examples 1-5

[0130]

[0131] (1) Solubility test of whole grain super concentrated nutritional essence instant milk tea

[0132] In order to explore the effect of spray drying on the solubility of milk tea, comparative examples 1-4 were set up based on Example 1 as follows:

[0133] Comparative Example 1

[0134] The only difference between this comparative example and Example 1 is that the inlet air temperature is 160°C.

[0135] Comparative Example 2

[0136] The only difference between this comparative example and Example 1 is that the air inlet temperature is 200°C.

[0137] Comparative Example 3

[0138] The difference between this comparative example and Example 1 is that the air outlet temperature is 70°C.

[0139] Comparative Example 4

[0140] The difference between this comparative example and Example 1 is that the air outlet temperature is 90°C.

[0141] The solubility test of the milk tea prepared in Comparative Examples 1-4 and Example 1 was carried out using the same solubility test method as above. The test results are shown in Table 2 below:

[0142] Table 2 Solubility test results of milk tea prepared in Comparative Examples 1-4 and Example 1

[0143] Sample No. Mixture state Particle distribution Average particle size (μm) Solubility (%) Example 1 Evenly dispersed Uniform 32 95 Comparative Example 1 Partial reunion Uneven 45 80 Comparative Example 2 Partial reunion Uneven 20 85 Comparative Example 3 Average dispersion Uneven 24 84 Comparative Example 4 Partial reunion Uneven 25 82

[0144] (II) Nutritional value test

[0145] (1) Component retention test

[0146] In order to explore the effect of freeze drying on the retention rate of ingredients, comparative examples 5-8 were set up based on Example 1 as follows:

[0147] Comparative Example 5

[0148] The only difference between this comparative example and Example 1 is that the freeze-drying temperature is -40°C.

[0149] Comparative Example 6

[0150] The only difference between this comparative example and Example 1 is that the freeze-drying temperature is -60°C.

[0151] Comparative Example 7

[0152] The only difference between this comparative example and Example 1 is that the vacuum degree of freeze drying is 0.05 mbar.

[0153] Comparative Example 8

[0154] The only difference between this comparative example and Example 1 is that the freeze-drying temperature is 0.2 mbar.

[0155] The milk teas of Comparative Examples 5-8 and Example 1 were subjected to component analysis using a high performance liquid chromatograph (HPLC), and the component retention rate was tested, and the sublimation rate during freeze drying was tested. The test results are shown in Table 3 below.

[0156] Table 3 Test results of ingredient retention rate and freeze drying sublimation rate of comparative examples 5-8 and embodiment 1

[0157]

[0158]

[0159] As shown in Table 3, when the temperature is increased to -40 ° C, the drying time is shortened to 20 hours, but the component retention rate drops to 85%, because the higher temperature accelerates the sublimation process, resulting in the loss of some effective ingredients. When the temperature is reduced to -60 ° C, the drying time is extended to 28 hours, and the component retention rate rises slightly to 87%, because the lower temperature slows down the sublimation rate, so that the loss of effective ingredients is reduced. When the vacuum degree is reduced to 0.05 mbar, the drying time is shortened to 18 hours, and the component retention rate drops to 82%, because the lower vacuum degree accelerates the sublimation process, resulting in the loss of effective ingredients. When the vacuum degree is increased to 0.2 mbar, the drying time is extended to 30 hours, and the component retention rate is 83%, because the higher vacuum degree slows down the sublimation rate, but also increases the drying time. Therefore, it can be seen that adjusting the temperature and vacuum degree of freeze drying in the present application scheme will cause the component retention rate to change.

[0160] (2) Nutritional content test

[0161] In order to verify the effects of various steps of the present invention on the nutritional components in milk tea, the raw materials of Examples 1-5 and the samples after supercritical fluid extraction, enzymatic hydrolysis and microwave-assisted extraction were analyzed by high performance liquid chromatography (HPLC). The test results are shown in Table 4 below.

[0162] Table 4 Test of nutrient content of Examples 1-5

[0163]

[0164]

[0165] As shown in Table 4, the content of effective ingredients in milk tea can be significantly increased after being treated with supercritical fluid extraction, enzymatic hydrolysis and microwave-assisted extraction in sequence. In addition, enzymatic hydrolysis can decompose macromolecular substances, improve the protein absorbability of the extract, and increase the functionality and health benefits of the product.

[0166] (III) Stability test

[0167] (1) Microencapsulation stability test experiment

[0168] In order to verify the effect of the microencapsulation step on the stability of the sample, the microcapsule samples obtained after microencapsulation in Examples 1-5 were kept at room temperature for 6 months and the content of each active ingredient was tested. The test results are shown in Table 5 below.

[0169] Table 5 Stability test results

[0170]

[0171]

[0172] As shown in Table 5, the microencapsulation embedding rates of Examples 1-5 are all above 90%, and after being stored at room temperature for six months, the effective substance content can still be maintained at above 88%.

[0173] Furthermore, based on Examples 1-5, comparative examples 9-13 without microencapsulation were set up, and the total active ingredient contents after 1 month, 3 months and 6 months were tested respectively. The test results are shown in Table 6 below.

[0174] Table 6 Comparative results of microencapsulation stability test of Examples 1-5 and Comparative Examples 9-13

[0175]

[0176]

[0177] As shown in Table 6, the content of active ingredients in the samples without microencapsulation decreased significantly after 6 months of storage compared with the samples after microencapsulation, indicating that the microencapsulation step can significantly improve the stability of the samples at room temperature and effectively protect the active ingredients from degradation over time. This shows that microencapsulation is an effective method to improve product stability and extend shelf life.

[0178] Therefore, microencapsulation can significantly extend the shelf life of the product, allowing it to maintain a high content of active ingredients and antioxidant activity after being stored at room temperature for 6 months, which is of great significance for product marketing and consumer use.

[0179] (2) Stability test of whole grain super concentrated nutritional essence instant milk tea

[0180] In order to test the storage stability of the whole grain super concentrated nutritional essence instant milk tea prepared in the present application at room temperature, a comparative example 14 was set on the basis of Example 2. The difference between Comparative Example 14 and Example 2 was only that the freeze drying step was not performed. The whole grain super concentrated nutritional essence instant milk tea obtained in Example 2 and Comparative Example 14 was tested for a shelf life of 12 months, and the content of various active ingredients was tested every three months. The test results are shown in Table 7 below.

[0181] Table 7 Stability test results

[0182]

[0183]

[0184] As shown in Table 7, after being stored at room temperature for 12 months, the content of effective substances in the whole grain super concentrated nutritional essence instant milk tea of ​​the present application changes little, indicating that the technical solution of the present application can improve the stability of the milk tea and can further extend its shelf life so that it can still maintain a high content of effective substances within 12 months.

[0185] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for preparing whole grain super concentrated nutritional essence instant milk tea, characterized in that: The following steps are involved: S1: Grind the whole grains and the nutritious ingredients and mix them evenly, then add purified water at a material-liquid ratio of 1:(3-7) and soak for 3-5 hours; then perform supercritical fluid extraction, filter, and obtain a mixed extract; the nutritious ingredients include spirulina, wolfberry, and maca; S2: adding a composite enzyme to the mixed extract for enzymolysis to obtain an enzymolysis mixture; the composite enzyme comprises cellulase and protease; S3: mixing the enzymatic hydrolysis mixture with an ethanol solution having a mass concentration of 70% at a volume ratio of 1:10, performing microwave-assisted extraction, and filtering to obtain a microwave-assisted extract; S4: subjecting the microwave-assisted extract to two high-pressure homogenization treatments to a particle size of 80-100 mesh; S5: microencapsulating the sample after high-pressure homogenization in step S4, using gum arabic as the wall material, mixing the sample and gum arabic in a mass ratio of 1:(2-5), and then using microencapsulation technology to form microcapsules, wherein the particle size of the microcapsules is 1-5 μm; drying the microcapsules, and then mixing them with a milk base and a tea base to obtain whole grain ultra-concentrated nutritional essence instant milk tea.

2. The method for preparing the whole grain super concentrated nutritional essence instant milk tea according to claim 1, characterized in that: The whole grains include the following components in proportion by weight: 10-20 parts of oats, 5-10 parts of brown rice, 5-10 parts of coix seeds, 5-10 parts of black rice and 5-10 parts of quinoa.

3. The method for preparing the whole grain super concentrated nutritional essence instant milk tea according to claim 2, characterized in that: The mass ratio of spirulina, wolfberry and maca is (3-5): (3-5): (2-5).

4. The method for preparing the whole grain super concentrated nutritional essence instant milk tea according to claim 3, characterized in that: The mass ratio of the whole grains, the nutritious ingredients, the tea base and the milk base is (23-45):(15-30):(10-20):

5.

5. The method for preparing the whole grain super concentrated nutritional essence instant milk tea according to claim 1, characterized in that: The supercritical fluid extraction is performed at least three times; the pressure of the supercritical fluid extraction is 250-350 bar, the temperature is 30-35° C., and the extraction time is 1.5-2.5 h.

6. The method for preparing the whole grain super concentrated nutritional essence instant milk tea according to claim 1, characterized in that: The microwave-assisted extraction is performed at least three times.

7. The method for preparing the whole grain super concentrated nutritional essence instant milk tea according to claim 1, characterized in that: The mass ratio of the cellulase to the protease is (2-5):(1-2).

8. The method for preparing the whole grain super concentrated nutritional essence instant milk tea according to claim 1, characterized in that: The pressure of the high temperature homogenization treatment is 100-300 bar.

9. The method for preparing the whole grain super concentrated nutritional essence instant milk tea according to claim 1, characterized in that: The drying process specifically comprises the following steps: The microcapsules were spray dried at an inlet air temperature of 180±5°C and an outlet air temperature of 80±5°C; the spray-dried sample was pre-frozen at -50±2.5°C for 3-4h, and then the vacuum degree was adjusted to 0.1±0.02mbar, and freeze-dried until the moisture content was less than 2%.

10. A whole grain super concentrated nutritional essence instant milk tea, characterized in that: The instant milk tea with super-concentrated whole grain nutritional essence is prepared by the preparation method of any one of claims 1 to 9.

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