Kiwi fruit raw material-based meal replacement powder and preparation method therefor

Abstract

A kiwi fruit raw material-based meal replacement powder preparation method, comprising: freeze-drying kiwi fruit to obtain a freeze-dried kiwi fruit powder, and pre-gelatinizing a konjac refined powder to obtain a pre-gelatinized konjac refined powder; using carrageenan, the pre-gelatinized konjac refined powder, xylitol, oat powder, whey protein and magnesium oxide to prepare a mixture I, and then adding the kiwi fruit freeze-dried powder, multivitamin, ferrous gluconate, zinc citrate and sodium tripolyphosphate to prepare a mixture II; performing melting and dispersing treatment on the mixture, and then cooling and pulverizing same to prepare a product.

Description

A meal replacement powder based on kiwifruit and its preparation method Technical Field

[0001] This invention relates to a method for preparing meal replacement powder based on kiwifruit. Background Technology

[0002] Currently, many meal replacement powders suffer from poor palatability due to their dry texture, tendency to clump after mixing, and unsuitable taste. This is primarily caused by improper ingredient combinations and outdated manufacturing processes. Regarding nutritional balance, some products either overemphasize fat loss while neglecting the proportions of key nutrients like protein and vitamins, or they offer a limited range of nutrients, failing to provide adequate nutritional supplementation. The feeling of fullness also lasts only a short time, making it difficult to sustain energy expenditure for extended periods. This is related to the types and amounts of satiating components in the powder. Furthermore, some products suffer from limited functionality, serving only as meal replacements without offering other beneficial effects. Therefore, developing a freeze-dried meal replacement powder that offers good taste, nutritional balance, a strong feeling of fullness, and comprehensive functionality is of great significance.

[0003] Kiwifruit contains actinidin, an active protease that can directly act on the protein in meal replacements and the intestinal environment, relieving the digestive burden of high-protein meal replacements. Therefore, using kiwifruit powder as a raw material in meal replacement powder preparation effectively improves the nutritional value of the powder, promotes intestinal peristalsis, and enhances the body's absorption efficiency of protein in high-protein meal replacements. However, in the process of mixing kiwifruit powder with other components to prepare meal replacement powder, the insoluble fiber in kiwifruit powder easily causes agglomeration, resulting in clumping and a rough texture during preparation. Kiwifruit powder is also rich in fruit acids, which can easily cause protein denaturation and precipitation when in contact with protein during long-term storage or preparation. While actinidin can aid protein digestion, it can also slowly decompose the protein during long-term storage, leading to protein structure damage and the production of bitter peptides, affecting the taste and protein function of the meal replacement powder. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing meal replacement powder based on kiwifruit.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A method for preparing a meal replacement powder based on kiwifruit includes the following steps:

[0007] S1. Raw material pretreatment

[0008] (1) Wash and peel the kiwifruit, cut it into small pieces, and freeze-dry it to obtain kiwifruit freeze-dried powder;

[0009] (2) Konjac flour is pregelatinized to obtain pregelatinized konjac flour;

[0010] S2. Mixing

[0011] (1) According to the weight parts, carrageenan, pregelatinized konjac flour, xylitol, oat flour, whey protein and magnesium oxide are prepared into mixture I;

[0012] (2) Add kiwi freeze-dried powder, compound vitamins, ferrous gluconate, zinc citrate and sodium tripolyphosphate in sequence to make mixture II;

[0013] S3. Melting treatment

[0014] Mixture II is fed into a twin-screw extruder for melt dispersion treatment;

[0015] S4. Cooling and pulverizing

[0016] The material extruded from the twin-screw extruder head is placed under an air-cooling system, with the cooling rate controlled at 5~10℃ / min, and cooled to room temperature. Then it is pulverized and passed through an 80~100 mesh sieve to obtain meal replacement powder.

[0017] Preferably, the kiwifruit freeze-drying process involves pre-freezing at -50 to -45°C for 5 to 6 hours, then turning on the vacuum and setting it to -0.05 MPa to -0.08 MPa, heating at a rate of 8 to 10°C / h to -20 to -15°C, maintaining the temperature for 10 to 12 hours, and then pulverizing the kiwifruit through a 120-mesh sieve.

[0018] Preferably, the pregelation is carried out by mixing konjac flour and water at a mass ratio of 1:15~20, stirring at 200~300 rpm for 10~12 min, freezing at -40~-35℃ for 2~3 h, adjusting the vacuum degree to 8~10 Pa, drying at 20~30℃, and then pulverizing into particles with a particle size of 100~200 μm.

[0019] Preferably, carrageenan is added to warm water at 40-45°C to form a 0.5% dilute solution. Pregelatinized konjac flour, xylitol, and oat flour are added and stirred at 500-600 rpm for 8-10 minutes. Then whey protein and magnesium oxide are added and stirred for another 5-8 minutes. The mixture is then heated to 65-70°C and stirred at 200-300 rpm for 4-6 minutes to form mixture I.

[0020] Preferably, by weight, the mixture I contains 2-5 parts carrageenan, 10-15 parts pregelatinized konjac flour, 6-8 parts xylitol, 20-25 parts oat flour, 15-20 parts whey protein, and 1-3 parts magnesium oxide.

[0021] Preferably, after mixture I cools to room temperature, kiwi freeze-dried powder, compound vitamins, ferrous gluconate, zinc citrate, and sodium tripolyphosphate are added sequentially, and the mixture is stirred at 1000~1200 rpm for 5~8 min to obtain mixture II.

[0022] Preferably, by weight, the mixture II contains 20-30 parts of freeze-dried kiwi fruit powder, 1-2 parts of compound vitamins, 0.3-0.5 parts of ferrous gluconate, 0.3-0.5 parts of zinc citrate, and 0.05-0.08 parts of sodium tripolyphosphate.

[0023] Preferably, the feed temperature of the melt dispersion treatment is 40-50℃, the melting temperature is 60-70℃, the homogenization temperature is 50-60℃, the die head temperature is 55-65℃, and the screw speed is 150-200 r / min.

[0024] A key indicator of satiety in meal replacement powder is its expansion efficiency after being mixed with water. Because the raw materials contain high levels of dietary fiber and protein, meal replacement powder expands after absorbing water, efficiently filling the stomach and enhancing satiety. However, maintaining this expanded state is crucial for achieving satiety. In this invention, although the added konjac flour contains glucomannan, it undergoes pre-gelation. Under alkaline conditions (pH adjusted with sodium tripolyphosphate and magnesium oxide), the degree of deacetylation is increased. The deacetylated konjac flour dissolves and gels rapidly during mixing, forming an interpenetrating network with the double helix structure of carrageenan through hydrogen bonds and hydrophobic interactions. This significantly improves gel strength, increases the expansion rate of the meal replacement powder, and stabilizes the expanded structure.

[0025] Oatmeal has a high starch content, which gelatinizes and absorbs water during preparation, increasing the expansion rate of meal replacement powders. However, this gelatinization can also lead to the binding of free metal ions, causing structural rearrangement and aging, ultimately resulting in the collapse of the expanded structure. Sodium tripolyphosphate (STP), on the other hand, can bind to free metal ions, reducing the binding between metal ions and starch molecules. Furthermore, STP and MgO adjust the pH of the system, inhibiting starch molecule aggregation. Additionally, STP's phosphate groups interact with the hydroxyl groups of starch molecules, anchoring the gelatinized molecules and preventing excessive aggregation. This reduces starch molecule rearrangement and maintains the integrity of the expanded starch structure.

[0026] Meal replacement powders need to balance satiety and bowel regularity. Konjac flour and oats contain a large amount of soluble dietary fiber, which can significantly increase satiety. However, soluble dietary fiber alone can slow down intestinal peristalsis and easily lead to constipation. Kiwifruit, on the other hand, contains a large amount of insoluble dietary fiber, which stimulates the intestinal wall and promotes intestinal peristalsis, complementing the soluble dietary fiber. Furthermore, the kiwifruit alkaloid active ingredient promotes protein absorption, reducing the digestive burden of high protein intake on the stomach and intestines, while also stimulating intestinal peristalsis and improving intestinal motility. However, freeze-dried kiwifruit powder contains abundant fruit acids, which can easily cause protein denaturation and precipitation when in contact with protein during long-term storage or preparation. Although the kiwifruit alkaloid it contains can aid protein digestion, it can slowly decompose the protein during long-term storage, leading to protein structure damage and the production of bitter peptides, affecting the taste and protein function of the meal replacement powder.

[0027] In this invention, sodium tripolyphosphate and MgO are used to adjust the pH of the system, neutralizing the fruit acids in the freeze-dried kiwi fruit powder and inhibiting protein denaturation caused by fruit acids upon contact with other proteins. Furthermore, in this invention, oat flour, konjac flour, and carrageenan are first mixed to form a preliminary loose structure. After adding whey protein, the mixture is stirred at a medium-speed within a specific temperature to promote the whey protein's penetration and filling of the structure. Then, the temperature is increased and the stirring speed is decreased. At this temperature, starch gelatinization and continuous stirring promote the rearrangement of the structure around the protein. As the temperature decreases, the structure shrinks and densifies, forming... A denser barrier is formed when kiwi freeze-dried powder is added later. Under high-speed stirring, centrifugal force causes the kiwi freeze-dried powder to embed into the barrier surface, preventing direct contact between protein molecules and the kiwi freeze-dried powder. During melting and dispersion, the starch and other components in the oat colloid in the network colloid undergo secondary gelatinization and melt with carrageenan to form a gel network that interpenetrates and fuses, further densifying the network and encapsulating the kiwi freeze-dried powder. This reduces the loss of vitamin C and buffers the effect of temperature on the protein during melting and dispersion, inhibiting excessive protein denaturation that could lead to clumping and insolubility during subsequent brewing.

[0028] The present invention has the following technical effects:

[0029] This invention effectively improves the expansion rate and structural stability of meal replacement powder by pretreating konjac flour, adding sodium tripolyphosphate, MgO, and other components, and combining this with a specific preparation process. Simultaneously, the addition of kiwi powder effectively mitigates the negative impact on protein in the meal replacement powder and inhibits the loss of vitamin C from the kiwi powder, thus stabilizing the nutritional value of the meal replacement powder. Embodiments of the present invention

[0030] The present invention will be specifically described below through embodiments. These embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention.

[0031] The compound vitamins used in this invention were purchased from Hubei Haijia Biotechnology Co., Ltd., and their specific nutrient indicators are as follows:

[0032] Vitamin B1 86.89 mg / g, Niacin 286.81 mg / g, Vitamin B2 77.55 mg / g, Folic Acid 4108.81 μg / g, Vitamin B6 91.32 mg / g, Pantothenic Acid 130.25 μg / g, Vitamin B12 142.06 μg / g

[0033] Example 1

[0034] A method for preparing a meal replacement powder based on kiwifruit includes the following steps:

[0035] S1. Raw material pretreatment

[0036] (1) Wash and peel the kiwifruit, cut it into small pieces, pre-freeze it at -45℃ for 6 hours, then turn on the vacuum degree, set the vacuum to -0.06MPa, raise the temperature to -20℃ at a rate of 10℃ / h, keep the temperature constant for 10 hours, and then crush it through a 120-mesh sieve to obtain kiwifruit freeze-dried powder.

[0037] (2) Mix konjac flour and water at a mass ratio of 1:18, stir at 250 rpm for 12 min, then freeze at -40℃ for 2 h, then adjust the vacuum degree to 8 Pa, dry at 25℃, and then pulverize into pregelatinized konjac flour with a particle size of 100~200 μm.

[0038] S2. Mixing

[0039] (1) According to the weight, add 4 parts of carrageenan to 45°C warm water to form a 0.5% dilute solution. Add 12 parts of pregelatinized konjac flour, 7 parts of xylitol and 24 parts of oat flour. Stir at 550 rpm for 10 min. Then add 18 parts of whey protein and 2 parts of magnesium oxide and continue stirring for 6 min. Then heat to 70°C and stir at 300 rpm for 4 min to form mixture I.

[0040] (2) After mixture I cools to room temperature, add 25 parts of kiwi freeze-dried powder, 1.5 parts of compound vitamins, 0.4 parts of ferrous gluconate, 0.4 parts of zinc citrate and 0.06 parts of sodium tripolyphosphate in sequence, and stir at 1100 rpm for 6 min to obtain mixture II;

[0041] S3. Melting treatment

[0042] Mixture II was fed into a twin-screw extruder, and the temperatures of each section of the extruder were set as follows: feed section 45℃, melting section 65℃, homogenization section 55℃, die head temperature 60℃; screw speed was 180 r / min.

[0043] S4. Cooling and pulverizing

[0044] The material extruded from the twin-screw extruder head is placed under an air-cooled cooling system at a cooling rate of 6°C / min until it reaches room temperature. Then it is pulverized and passed through a 100-mesh sieve to obtain meal replacement powder.

[0045] Comparative Example 1

[0046] Compared with Example 1, the konjac flour was not pre-gelled, but the remaining steps were the same as in Example 1.

[0047] Comparative Example 2

[0048] Compared with Example 1, in the mixing process, after the whey protein was added, there was no heating and slowing down the stirring. Step (2) was carried out directly. The remaining steps were the same as in Example 1.

[0049] Comparative Example 3

[0050] Compared with Example 1, the difference is that the order of adding MgO and sodium tripolyphosphate during the mixing process is changed, while the other steps remain the same.

[0051] Take equal amounts (10g, bulk density 0.53, initial volume approximately 18.9 mL, i.e. V1) of the meal replacement powder prepared in Example 1 and each comparative example, add an equal amount of room temperature water (100mL) to test the expansion rate of the prepared meal paste, and then place it at 4℃ to cool to room temperature and observe the volume change of the meal paste again. The expansion rate is calculated using the following formula:

[0052] R(v) = (V) 总 -V 水 ) / V1×100%

[0053] In the formula V 总 V: The total volume after the meal replacement powder has fully expanded after brewing and standing. 水 V1: Volume of water used for preparation; V2: Naturally accumulated volume of meal replacement powder. The results are shown in Table 1.

[0054] Table 1:

[0055] Expansion Volume Expansion Rate and Volume Change Rate After Cooling: Example 1: 176.3%, 456.7%, 173.8%, -6.71%; Comparative Example 1: 152.9%, 332.8%, 152.4%, -12.58%; Comparative Example 2: 144.7%, 289.4%, 139.9%, -9.57%; Comparative Example 3: 167.4%, 409.5%, 165.3%, -6.82%.

[0056] It can be seen that during the brewing process, the expansion rate of the meal replacement powder in Example 1 was significantly higher than that in Comparative Example 1 and Comparative Example 2, and the volume shrinkage after cooling was also minimal.

[0057] The meal replacement powders prepared in Example 1 and each comparative example were added to 60°C warm water for brewing. The brewing characteristics and taste were observed. The meal replacement powders were placed in a room temperature environment for 12 months, and their powder characteristics were observed. The results are shown in Table 2.

[0058] Table 2:

[0059] Brewing Properties and Taste: Powder after 12 months of storage: Example 1: Dissolves quickly upon brewing, the paste is evenly and stably dispersed, with no undissolved clumps or particles, and has a faint milky aroma. The powder is evenly and loosely dispersed. Comparative Example 1: Slight insolubility occurs during brewing. The paste tastes bitter, the milky aroma diminishes, and the loose texture transforms into a sticky, lumpy consistency. Comparative Example 2: Slight insolubility occurs during brewing. The paste tastes bitter, the milky aroma diminishes, and the loose texture transforms into a sticky, lumpy consistency. Comparative Example 3: Obvious lumps and insolubility occur during brewing. The paste tastes significantly bitter, lacks a milky aroma, and the loose texture transforms into a sticky, severely lumpy consistency.

[0060] The meal replacement powder prepared in Example 1 exhibits stable storage properties and excellent brewing characteristics and taste. However, in Comparative Example 1, the konjac flour was not pretreated, resulting in poor barrier effects against the protein and kiwi powder. After long-term storage, contact between the two leads to protein denaturation. Comparative Example 2 also faces similar problems. In Comparative Example 3, the addition of sodium tripolyphosphate first anchors starch molecules during the initial heating and gelatinization process, preventing the formation of a dense film layer around the protein molecules. This results in incomplete protein coating. When kiwi freeze-dried powder is added subsequently, contact between the two leads to severe protein denaturation during the melting and dispersion process, which is exacerbated during long-term storage.

[0061] Tests on changes in vitamin C content in meal replacement powders:

[0062] Take the sample, extract it with 1% oxalic acid solution to remove impurities and obtain the test solution. Take 2 mL of the test solution and add 0.5 mL of 1% o-phenylenediamine solution and 0.5 mL of 0.1 mol / L hydrochloric acid. React in the dark for 30 min. Prepare vitamin C standard solutions with concentrations of 0, 5, 10, 20, and 40 μg / mL. Develop the color according to the above steps. Measure the fluorescence intensity at an excitation wavelength of 350 nm and an emission wavelength of 430 nm, and plot the "concentration-fluorescence intensity" standard curve. Sample determination: Measure the fluorescence intensity of the test solution, substitute it into the standard curve equation, and calculate the vitamin C content in the sample.

[0063] The vitamin C in the meal replacement powder mainly comes from freeze-dried kiwi fruit powder. The vitamin C content in the freeze-dried kiwi fruit powder was tested according to the above method. After the meal replacement powder was prepared, the vitamin C content in the meal replacement powder was tested. After the meal replacement powder was stored for 12 months, the vitamin C content in the meal replacement powder was tested again. The changes in vitamin C during the preparation and storage process were observed. The results are shown in Table 3.

[0064] Table 3:

[0065] Vitamin C content (mg / 100g) in freeze-dried kiwi fruit powder; initial vitamin C content (mg / 100g) in meal replacement powder; vitamin C content (mg / 100g) in meal replacement powder after 12 months; Example 1: 123.7, 28.6, 27.7; Comparative Example 1: 122.9, 19.8, 15.2; Comparative Example 2: 123.4, 23.2, 13.3; Comparative Example 3: 124.8, 16.7, 12.9

[0066] It can be seen that, during the preparation of the meal replacement powder, the vitamin C content of Comparative Examples 1-3 was lost to varying degrees compared with Example 1. After 12 months of storage, the amount of vitamin C lost in the meal replacement powder of Example 1 was significantly lower than that of the comparative examples.

[0067] Example 2

[0068] A method for preparing a meal replacement powder based on kiwifruit includes the following steps:

[0069] S1. Raw material pretreatment

[0070] (1) Wash and peel the kiwifruit, cut it into small pieces, pre-freeze it at -50℃ for 5 hours, then turn on the vacuum degree, set the vacuum to -0.05MPa, raise the temperature to -15℃ at a rate of 8℃ / h, keep the temperature constant for 12 hours, and then crush it through a 120-mesh sieve to obtain kiwifruit freeze-dried powder.

[0071] (2) Mix konjac flour and water at a mass ratio of 1:15, stir at 300 rpm for 10 min, freeze at -35℃ for 3 h, adjust the vacuum degree to 10 Pa, dry at 20℃, and then pulverize into pregelatinized konjac flour with a particle size of 100~200 μm.

[0072] S2. Mixing

[0073] (1) According to the weight, add 2 parts of carrageenan to warm water at 40~45℃ to form a dilute solution with a concentration of 0.5%. Add 10 parts of pregelatinized konjac flour, 6 parts of xylitol and 20 parts of oat flour. Stir at 500rpm for 10min. Then add 15 parts of whey protein and 1 part of magnesium oxide and continue stirring for 5min. Then heat to 65℃ and stir at 200rpm for 6min to form mixture I.

[0074] (2) After mixture I cools to room temperature, add 20 parts of kiwi freeze-dried powder, 1 part of compound vitamin, 0.3 parts of ferrous gluconate, 0.3 parts of zinc citrate and 0.05 parts of sodium tripolyphosphate in sequence, and stir at 1000 rpm for 8 min to obtain mixture II;

[0075] S3. Melting treatment

[0076] Mixture II was fed into a twin-screw extruder, and the temperatures of each section of the extruder were set as follows: feed section 40°C, melting section 60°C, homogenization section 50°C, and die head temperature 55°C; the screw speed was 150 r / min.

[0077] S4. Cooling and pulverizing

[0078] The material extruded from the twin-screw extruder head is placed under an air-cooled cooling system at a cooling rate of 5°C / min until it reaches room temperature. Then it is pulverized and passed through an 80-mesh sieve to obtain meal replacement powder.

[0079] The meal replacement powder prepared in this embodiment dissolves rapidly upon reconstitution, with the paste dispersed evenly and stably, without any undissolved clumps or particles. It has a light milky aroma, and its expansion rate upon reconstitution reaches 434.7%, while its volume decreases by 6.81% after cooling. The meal replacement powder did not exhibit stickiness or clumping during long-term storage, demonstrating excellent stability and maintaining a stable vitamin C content.

[0080] Example 3

[0081] A method for preparing a meal replacement powder based on kiwifruit includes the following steps:

[0082] S1. Raw material pretreatment

[0083] (1) Wash and peel the kiwifruit, cut it into small pieces, pre-freeze it at -48℃ for 5.5h, then turn on the vacuum degree, set the vacuum to -0.08MPa, heat it to -18℃ at a heating rate of 9℃ / h, keep it at a constant temperature for 11h, and then crush it through a 120-mesh sieve to obtain kiwifruit freeze-dried powder.

[0084] (2) Mix konjac flour and water at a mass ratio of 1:20, stir at 300 rpm for 10 min, then freeze at -38℃ for 2.5 h, then adjust the vacuum degree to 9 Pa, dry at 30℃, and then pulverize into pregelatinized konjac flour with a particle size of 100~200 μm.

[0085] S2. Mixing

[0086] (1) According to the weight, add 5 parts of carrageenan to 42°C warm water to form a 0.5% dilute solution. Add 15 parts of pregelatinized konjac flour, 8 parts of xylitol and 25 parts of oat flour. Stir at 500~600 rpm for 9 min. Then add 20 parts of whey protein and 3 parts of magnesium oxide and continue stirring for 8 min. Then heat to 68°C and stir at 250 rpm for 5 min to form mixture I.

[0087] (2) After mixture I cools to room temperature, add 30 parts of kiwi freeze-dried powder, 2 parts of compound vitamins, 0.5 parts of ferrous gluconate, 0.5 parts of zinc citrate and 0.08 parts of sodium tripolyphosphate in sequence, and stir at 1200 rpm for 5 min to obtain mixture II;

[0088] S3. Melting treatment

[0089] Mixture II was fed into a twin-screw extruder, and the temperatures of each section of the extruder were set as follows: feed section 50℃, melting section 70℃, homogenization section 60℃, die head temperature 65℃; screw speed was 200 r / min.

[0090] S4. Cooling and pulverizing

[0091] The material extruded from the twin-screw extruder head is placed under an air-cooled cooling system at a cooling rate of 10℃ / min until it reaches room temperature. Then it is pulverized and passed through a 100-mesh sieve to obtain meal replacement powder.

[0092] The meal replacement powder prepared in this embodiment dissolves rapidly upon reconstitution, with the paste dispersed evenly and stably, without any undissolved clumps or particles. It has a light milky aroma, and its expansion rate upon reconstitution reaches 446.9%, with a volume decrease of 6.49% after cooling. The meal replacement powder did not exhibit stickiness or clumping during long-term storage, demonstrating excellent stability and maintaining a stable vitamin C content.

Claims

1. A method for preparing a meal replacement powder based on kiwifruit, characterized in that, Includes the following steps: S1. Raw material pretreatment (1) Wash and peel the kiwifruit, cut it into small pieces, and freeze-dry it to obtain kiwifruit freeze-dried powder; (2) Konjac flour is pregelatinized to obtain pregelatinized konjac flour; S2. Mixing (1) According to the weight parts, carrageenan, pregelatinized konjac flour, xylitol, oat flour, whey protein and magnesium oxide are prepared into mixture I; (2) Add kiwi freeze-dried powder, compound vitamins, ferrous gluconate, zinc citrate and sodium tripolyphosphate in sequence to make mixture II; S3. Melting treatment Mixture II was fed into a twin-screw extruder for melt dispersion. S4. Cooling and pulverizing The material extruded from the twin-screw extruder head is placed under an air-cooling system, with the cooling rate controlled at 5~10℃ / min, and cooled to room temperature. Then it is pulverized and passed through an 80~100 mesh sieve to obtain meal replacement powder.

2. The preparation method according to claim 1, characterized in that: The freeze-drying of kiwifruit involves pre-freezing at -50 to -45°C for 5 to 6 hours, then turning on the vacuum and setting it to -0.05 MPa to -0.08 MPa, heating at a rate of 8 to 10°C / h to -20 to -15°C, maintaining the temperature for 10 to 12 hours, and then pulverizing it through a 120-mesh sieve.

3. The preparation method according to claim 2, characterized in that: The pregelation process involves mixing konjac flour and water at a mass ratio of 1:15~20, stirring at 200~300 rpm for 10~12 min, freezing at -40~-35℃ for 2~3 h, adjusting the vacuum degree to 8~10 Pa, drying at 20~30℃, and then pulverizing into particles with a diameter of 100~200 μm.

4. The preparation method according to claim 3, characterized in that: Add carrageenan to warm water at 40-45℃ to form a 0.5% dilute solution. Add pre-gelled konjac flour, xylitol and oat flour, and stir at 500-600 rpm for 8-10 minutes. Then add whey protein and magnesium oxide and continue stirring for 5-8 minutes. Then heat the mixture to 65-70℃ and stir at 200-300 rpm for 4-6 minutes to form mixture I.

5. The preparation method according to claim 4, characterized in that: By weight, the mixture I contains 2-5 parts carrageenan, 10-15 parts pregelatinized konjac flour, 6-8 parts xylitol, 20-25 parts oat flour, 15-20 parts whey protein, and 1-3 parts magnesium oxide.

6. The preparation method according to claim 5, characterized in that: After mixture I cools to room temperature, add kiwi freeze-dried powder, compound vitamins, ferrous gluconate, zinc citrate, and sodium tripolyphosphate in sequence, and stir at 1000-1200 rpm for 5-8 minutes to obtain mixture II.

7. The preparation method according to claim 6, characterized in that: By weight, the mixture II contains 20-30 parts of freeze-dried kiwi fruit powder, 1-2 parts of compound vitamins, 0.3-0.5 parts of ferrous gluconate, 0.3-0.5 parts of zinc citrate, and 0.05-0.08 parts of sodium tripolyphosphate.