High-load starch-based steady-state morinda citrifolia enzyme spray-dried microcapsule and preparation method thereof

Abstract

The invention discloses a high-load starch-based steady-state morinda citrifolia enzyme spray-dried microcapsule and a preparation method thereof, belongs to the technical field of food spray drying, and provides the high-load starch-based steady-state morinda citrifolia enzyme spray-dried microcapsule which comprises morinda citrifolia enzyme and modified starch N-zorbit M / porous starch. The preparation method comprises the following steps: stirring and mixing the morinda citrifolia enzyme and the wall material according to different proportions to obtain a morinda citrifolia enzyme and wall material mixed solution; and carrying out spray drying on the morinda citrifolia enzyme mixed solution to obtain the high-load starch-based morinda citrifolia enzyme spray-dried microcapsule. Modified starch N-zorbit M / porous starch is used as a wall material to prepare the high-load morinda citrifolia enzyme spray-dried microcapsule, so that the volatile unpleasant odor of morinda citrifolia enzyme is reduced, and the total phenol content and the oxidation resistance of the morinda citrifolia enzyme are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of food spray drying, and in particular relates to a high-load starch-based stable noni enzyme spray-dried microcapsule and a preparation method thereof. Background Art

[0002] Noni fruit (Morinda citrifolia Linn.), a plant of the Rubiaceae family, is primarily distributed in Hainan, the Xisha Islands, and Taiwan. Studies have shown that noni fruit contains a rich variety of bioactive components, including phenolic compounds, cyclopentane compounds, anthraquinone compounds, fatty acids, and lignans, which contribute to antioxidant, antibacterial, anti-inflammatory, anti-cancer, and immune-enhancing properties. Noni enzyme is a product containing specific active ingredients, produced using noni fruit as the primary raw material, with or without the addition of auxiliary materials, through a process of selection, washing, fermentation, juicing, filtration, homogenization, and sterilization. Due to the fruit's excellent health and medicinal properties, the development of noni enzyme products has garnered significant attention in recent years. In addition to preserving the fruit's inherent nutritional value, fermentation increases its total phenolic and flavonoid contents and reduces undesirable flavor compounds such as butyric acid and octanoic acid, which are abundant in the fruit. However, noni enzyme itself still contains a strong rancid smell. As a liquid product, its biologically active ingredients are easily affected by environmental factors such as light, heat, and oxygen during storage, transportation, and sales, resulting in the deterioration of the biologically active ingredients. This greatly limits the acceptability of noni enzyme and restricts the promotion and development of the product.

[0003] Spray drying microencapsulation technology involves combining a core material (polysaccharides, peptides, additives, etc.) with a corresponding wall material under the action of an emulsifier. Under certain conditions, the wall material tightly wraps around the core material surface, and a subsequent drying process results in powdered microcapsules. Spray drying microencapsulation technology can effectively encapsulate noni enzyme, effectively improving its physical and chemical properties and masking its unpleasant odor. However, using spray drying to concentrate noni enzyme still presents many problems. Among them, pectin and polysaccharides have high viscosity. The hydrophilic effect of these substances makes it difficult for water to evaporate quickly during drying, resulting in stickiness and wall deposition. Therefore, it is important to select the appropriate wall material and control the spray drying parameters to achieve the goal of preserving the biological active ingredients of noni enzyme and improving its flavor.

[0004] Combining drying technology can effectively process noni enzyme. Currently, the development of noni enzyme products primarily involves compounding multiple raw materials with noni enzyme or using multiple drying processes to form a powder. However, there is no simple and efficient process for improving noni enzyme powder, limiting the application of noni enzyme to specific products. Chinese patent CN 113679035 A describes a method for preparing a special dietary powder of noni fruit. The fermented noni enzyme is then concentrated by vacuum and spray-dried to convert the noni enzyme concentrate into noni fruit enzyme powder. The vacuum process prevents the destruction and loss of unstable components in the enzyme concentrate, while the spray drying process removes microbial contamination and preserves the flavor, color, and nutritional value of the noni enzyme. The vacuum freeze-drying conditions are a pressure of 0.01–0.02 MPa, a temperature of -20°C–-10°C, and a freezing time of 4–5 hours. This technique increases processing costs, and the continuous use of two drying techniques increases energy consumption, making it unsuitable for large-scale production. Chinese patent CN 108185339 A describes a noni enzyme composition and its preparation, produced by combining noni enzyme juice, blueberry juice, ginger extract, red date extract, and tremella extract using vacuum drying technology. The composition synergistically enhances anti-aging and immune-boosting effects, while also improving the inherent sour and pungent smell of noni enzyme and enhancing its taste. However, the addition of multiple raw materials requires multiple heating steps, making the preparation process complex and time-consuming.

[0005] The above-mentioned existing technologies have high operating costs, large energy consumption, and complicated processes. To address the above problems, the high-load starch-based stable noni enzyme spray-dried microcapsules produced under the preferred method of the present invention have the characteristics of less added raw materials, simple process, high loading capacity, significant odor masking effect, and maintained biological activity. Summary of the Invention

[0006] The present invention aims to address the above-mentioned deficiencies in the prior art by providing a high-load, starch-based, stable spray-dried microcapsule containing Morinda citrifolia enzyme. Maltodextrin National M1, modified starch N-zorbit M, and porous starch are mixed with Morinda citrifolia enzyme as protective agents, thereby increasing the loading capacity of Morinda citrifolia enzyme during the drying process, maintaining its biological activity, and masking unpleasant odors.

[0007] Another object of the present invention is to provide a method for preparing the microcapsules.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] S1. Weighing: Weigh the noni enzyme and starch-based material according to the following ratio: 10%-50% noni enzyme, 50%-90% starch-based material, and the sum of the percentages of all components is 100%.

[0010] S2. Mixing: Stir the weighed materials described in S1 using a magnetic stirrer until the wall material is completely dissolved.

[0011] S3. Spray drying: The instrument parameters were set to an inlet air temperature of 120-200°C, an air flow rate of 30 m³ / h, and a peristaltic pump speed of 10 rpm. The peristaltic pump was started to feed the material when the outlet air temperature reached 80-85°C.

[0012] Preferably, it is composed of the following components in percentage: 25% to 40% noni enzyme, 60% to 75% starch-based materials, and the sum of all component contents is 100%.

[0013] Furthermore, in step S1, the soluble solid content of the noni enzyme is adjusted to 5%-10%.

[0014] Preferably, the soluble solid content of the noni enzyme is adjusted to 6%-8%.

[0015] Furthermore, the starch-based material in step S1 is edible modified starch.

[0016] Preferably, the starch-based material in step S1 includes but is not limited to any one of modified starch N-zorbit M and porous starch.

[0017] Preferably, the core-to-wall ratio (w / w) of the noni enzyme and starch-based material is 1:5-1:1.

[0018] Furthermore, the core-wall ratio (w / w) of the noni enzyme and starch-based material is 1:4-2:3

[0019] Furthermore, the mixing in step S2 is performed by stirring the mixture at a speed of 800-1200 rpm using a magnetic stirrer and heating the mixture in a water bath at 50-80° C. for 15-45 minutes until the wall material is completely dissolved.

[0020] Preferably, the mixing in step S2 is performed by stirring the mixture at a speed of 1000 rpm using a magnetic stirrer and heating the mixture in a water bath at 50-80° C. for 15-45 minutes until the wall material is completely dissolved.

[0021] Preferably, the mixing in step S2 is performed by stirring the mixture at a speed of 1000 rpm using a magnetic stirrer and heating the mixture in a water bath at 70° C. for 15 to 45 minutes until the wall material is completely dissolved.

[0022] Preferably, the mixing in step S2 is performed by stirring the mixture at a speed of 1000 rpm using a magnetic stirrer and heating the mixture in a water bath at 70° C. for 30 minutes until the wall material is completely dissolved.

[0023] Further preferably, when the starch-based material in step S2 is modified starch N-zorbit M, the mixing in step S2 is performed by stirring at a speed of 1000 rpm using a magnetic stirrer until the wall material is completely dissolved.

[0024] Further preferably, when the starch-based material in step S2 is porous starch, the mixing in step S2 is stirred at a speed of 1000 rpm using a magnetic stirrer and heated in a water bath at 70° C. for 30 min until the wall material is completely dissolved.

[0025] Furthermore, the parameters of the S3 spray drying instrument are set as an inlet air temperature of 150-190°C, an air flow rate of 30 m³ / h, and a feed peristaltic speed of 10 rpm. When the outlet air temperature reaches 80-85°C, the peristaltic pump feed is started.

[0026] Compared with the prior art, the present invention has the following advantages and technical effects:

[0027] This invention proposes a starch-based spray-dried microcapsule containing stable noni enzyme and a preparation method thereof. Modified starch N-zorbit M and porous starch are mixed with noni enzyme as starch-based materials and then spray-dried. Spray drying effectively reduces the water content of the microcapsules, maintains strong resolubility, improves the fluidity of the microcapsules, reduces agglomeration, and significantly increases the total amount of polyphenols and antioxidant capacity in the microcapsules.

[0028] 1) The present invention is the first to use modified starch N-zorbit M and porous starch as the spray drying wall materials of noni enzyme, which helps to improve the water content, re-dissolution ability, fluidity and agglomeration of noni enzyme microcapsules, thereby realizing the process improvement of noni enzyme microcapsules.

[0029] 2) The high-load starch-based noni enzyme spray-dried microcapsules prepared by this method have high total phenol content and antioxidant capacity, which is conducive to its application in functional foods.

[0030] 3) The high-load starch-based noni enzyme spray-dried microcapsules prepared by this method have a simple and efficient preparation process, which helps to reduce production costs and improve the product quality of high-load starch-based steady-state noni enzyme spray-dried microcapsules. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 shows the starch-based noni enzyme sample solutions with different wall material types and loadings (from left to right: 25% solid content-maltodextrin National M1 mixture, 40% solid content-maltodextrin National M1 mixture, 25% solid content-modified starch N-zorbit M mixture, 40% solid content-modified starch N-zorbit M mixture, 40% solid content-porous starch mixture, 25% solid content-porous starch mixture.

[0032] Figure 2 shows images of starch-based noni enzyme microcapsules with different wall materials and different solid loadings at different drying temperatures (from left to right, from top to bottom: 40% noni enzyme, maltodextrin National M1, 150 ℃; 40% noni enzyme, modified starch N-zorbit M, 150 ℃; 40% noni enzyme, porous starch, 150 ℃; 25% noni enzyme, maltodextrin National M1, 150 ℃; 25% noni enzyme, modified starch N-zorbit M, 150 ℃; 25% noni enzyme, porous starch, 150 ℃; 40% noni enzyme, maltodextrin National M1, 190 ℃; 40% noni enzyme, modified starch N-zorbit M, 190 ℃; 40% noni enzyme, porous starch, 190 ℃; 25% noni enzyme, maltodextrin National M1, 190 ℃; 25% Noni enzyme, modified starch N-zorbit M, 190 ℃; 25% Noni enzyme, porous starch, 190 ℃)

[0033] Figure 3 shows the SEM images of 40% solid loading starch-based noni enzyme microcapsules with different wall materials and different drying temperatures (A: maltodextrin National M1 group, 150 °C; B: maltodextrin National M1 group, 190 °C; C: modified starch N-zorbit M group: 150 °C; D: modified starch N-zorbit M group: 190 °C; E: porous starch group: 150 °C; F: porous starch group: 190 °C)

[0034] Figure 4 shows the tap density of high-load starch-based stable noni enzyme spray-dried microcapsules at 150°C and 190°C drying conditions (different letters indicate significant differences, p<0.05)

[0035] Figure 5 shows the total phenol preservation rate of high-load starch-based stable noni enzyme spray-dried microcapsules with different wall materials and different solid contents at an inlet air drying temperature of 150°C.

[0036] Figure 6 shows the total phenol preservation rate of high-load starch-based stable noni enzyme spray-dried microcapsules with different wall materials and different solid contents at an inlet air drying temperature of 190°C.

[0037] Figure 7 shows the total antioxidant preservation rate of high-load starch-based stable noni enzyme spray-dried microcapsules with different wall materials and different solid contents at an inlet air drying temperature of 150°C.

[0038] Figure 8 shows the total antioxidant preservation rate of high-load starch-based stable noni enzyme spray-dried microcapsules with different wall materials and different solid contents at an inlet air drying temperature of 190°C. DETAILED DESCRIPTION

[0039] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0040] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0041] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0042] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the description of the invention. The description and examples are intended to be exemplary only.

[0043] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0044] Sources of the materials used in the present invention: National M1 maltodextrin and modified starch N-zorbit M were purchased from Innovent Biologics Co., Ltd.; porous starch was purchased from Shaanxi Baichuan Biotechnology Co., Ltd.; Noni enzyme stock solution was purchased from Hainan Xisha Noni Biotechnology Co., Ltd.; spray dryer was purchased from Shanghai Yacheng Instrument Equipment Co., Ltd., and digital display constant temperature water bath was purchased from Shanghai Lichen Bangxi Instrument Technology Co., Ltd.

[0045] The present invention will be further described below in conjunction with the embodiments:

[0046] Example 1

[0047] To prepare a sample containing noni enzyme, a noni enzyme with a solids content of 7.0 ± 0.2% was mixed with modified starch N-zorbit M at a core-to-wall ratio (w / w) of 1:3. The mixture was stirred at room temperature using a magnetic stirrer at 1000 rpm until the wall material was completely dissolved. The spray dryer was set to an inlet air temperature of 150°C, an air flow rate of 30 m³ / h, and a feed peristaltic speed of 10 rpm. The peristaltic pump feed was started when the outlet air temperature reached 80-85°C.

[0048] Example 2

[0049] The method is basically the same as Example 1, except that the ratio (w / w) of noni enzyme to modified starch N-zorbit M core wall is set to 2:3.

[0050] Example 3

[0051] The process is basically the same as Example 1, except that the air inlet temperature of the spray dryer is set to 190°C.

[0052] Example 4

[0053] The method is basically the same as Example 1, except that the core-wall ratio (w / w) of Noni enzyme and maltodextrin National M1 is set to 2:3, and the inlet air temperature of the spray dryer is set to 190°C.

[0054] Example 5

[0055] The noni enzyme with a solid content of 7.0±0.2% was mixed with porous starch at a core-to-wall ratio of 1:3 (w / w).

[0056] The sample containing noni enzyme was stirred at room temperature using a magnetic stirrer at 1000 rpm until the wall material was completely dissolved. The spray dryer was set to an inlet air temperature of 150°C, an air flow of 30 m³ / h, and a peristaltic feed speed of 10 rpm. The peristaltic pump feed was activated when the outlet air temperature reached 80-85°C.

[0057] Example 6

[0058] The method is basically the same as Example 5, except that the ratio of noni enzyme to porous starch core wall (w / w) is set to 2:3.

[0059] Example 7

[0060] The process is basically the same as Example 5, except that the air inlet temperature of the spray dryer is set to 190°C.

[0061] Example 8

[0062] The method is basically the same as Example 5, except that the ratio of noni enzyme to porous starch core wall (w / w) is set to 2:3, and the inlet air temperature of the spray dryer is set to 190°C.

[0063] Comparative Example 1

[0064] To prepare a sample containing noni enzyme, a noni enzyme with a solids content of 7.0 ± 0.2% was mixed with National M1 maltodextrin at a core-to-wall ratio of 1:3 (w / w). The mixture was stirred at room temperature using a magnetic stirrer at 1000 rpm until the wall material was completely dissolved. The spray dryer was set to an inlet air temperature of 150°C, an air flow of 30 m³ / h, and a peristaltic feed speed of 10 rpm. The peristaltic pump feed was activated when the outlet air temperature reached 80–85°C.

[0065] Comparative Example 2

[0066] The method is basically the same as Comparative Example 1, except that the ratio (w / w) of Noni enzyme to maltodextrin National M1 core wall is set to 2:3.

[0067] Comparative Example 3

[0068] The process is basically the same as Comparative Example 1, except that the air inlet temperature of the spray dryer is set to 190°C.

[0069] Comparative Example 4

[0070] The method is basically the same as Comparative Example 1, except that the core wall ratio (w / w) of Noni enzyme and maltodextrin National M1 is set to 2:3, and the air inlet temperature of the spray dryer is set to 190°C.

[0071] Test Example 1

[0072] Figure 2 shows the flowability of the different groups of noni enzyme microcapsules prepared in Examples 1-8 and Comparative Examples 1-4. Under the same drying temperature and solid loading conditions, the porous starch group exhibited the best flowability, followed by the modified starch N-zorbit M group. The maltodextrin National M1 group exhibited the worst flowability, and the maltodextrin National M1 group was more prone to agglomeration, which may be related to the friction between the dried particles.

[0073] Test Example 2

[0074] Table 1 shows the solubility results of the starch-based stable noni enzyme spray-dried microcapsules prepared in Examples 1-8 and Comparative Examples 1-4. Under drying conditions with an inlet air temperature of 150°C and 190°C, the dissolution times of microcapsules with different wall materials (maltodextrin National M1, modified starch N-zorbit M, and porous starch) showed significant differences (p < 0.05). Modified starch N-zorbit M had the shortest dissolution time, followed by maltodextrin National M1, and porous starch had the longest dissolution time. On the other hand, no significant differences in dissolution time were observed between microcapsules with the same drying temperature, wall material, and different solid loadings (p > 0.05). The shorter the dissolution time of a powder, the faster the dissolution rate, indicating that the powder has a stronger resolubility. The re-dissolution ability of starch-based stable noni enzyme spray-dried microcapsules had no significant correlation with solid loading (p > 0.05), but had a strong correlation with the wall material (maltodextrin National M1, modified starch N-zorbit M, porous starch) (p < 0.05). Among them, maltodextrin National M1 had the strongest re-dissolution ability, while porous starch had the weakest re-dissolution ability.

[0075] Table 1 Dissolution time of microcapsules under drying conditions of 150℃ and 190℃

[0076] Group 150 ℃ 190 ℃ Maltodextrin (40%) <![CDATA[165.83±9.46 a ]]> <![CDATA[165.13±12.05 a ]]> Maltodextrin (25%) <![CDATA[166.26±8.03 a ]]> <![CDATA[174.89±5.43 a ]]> Modified starch (40%) <![CDATA[116.60±9.36 a ]]> <![CDATA[129.47±8.93 a ]]> Modified starch (25%) <![CDATA[116.72±7.90 b ]]> <![CDATA[135.43±7.28 a ]]> Porous starch (40%) <![CDATA[206.46±14.30 a ]]> <![CDATA[204.30±7.74 a ]]> Porous starch (25%) <![CDATA[198.20±18.64 a ]]> <![CDATA[197.61±17.36 a ]]>

[0077] Note: Different letters in the same column indicate statistically significant differences (p < 0.05)

[0078] Drying temperature has a certain impact on dissolution time. As shown, the dissolution time of microcapsules prepared from modified starch N-zorbit M (25%) at 190°C inlet air drying temperature was significantly (p < 0.05) longer than that at 150°C inlet air drying temperature. This may be because at higher drying temperatures, the powder moisture evaporates further, forming a more solid shell that hinders particle dissolution.

[0079] The results show a strong correlation between different wall materials (maltodextrin National M1, modified starch N-zorbit M, and porous starch) and the resolubility of high-load starch-based stable noni enzyme spray-dried microcapsules. Microcapsules coated with modified starch N-zorbit M exhibited the shortest dissolution time and exhibited superior wettability and resolubility. Although drying temperature did affect the resolubility of microcapsules, resulting in a significant increase in the dissolution time of modified starch N-zorbit M at a higher drying temperature (190°C) (p < 0.05), modified starch N-zorbit M maintained relatively good resolubility. In actual production, we generally expect dry powders to have stronger resolubility. Therefore, if only the resolubility of the powder is considered, modified starch N-zorbit M is a better wall material choice for high-load starch-based noni enzyme spray-dried microcapsules.

[0080] Test Example 3

[0081] Electron microscopy scanning was performed on the microcapsules prepared in Examples 2, 4, 6, and 8 to observe the microstructure of the particles of noni enzyme with different wall materials and at different drying temperatures, and to explore the shell-forming behavior of the dried particles of noni enzyme. As shown in Figures 3A-3F, maltodextrin National M1 and modified starch N-zorbit M have similar spherical shapes with wrinkles on the surface, but the surface of modified starch N-zorbit M is smoother; porous starch forms a bowl-shaped structure with one side concave inward.

[0082] On the other hand, no significant effect of drying temperature on the shelling behavior of the granules was found. The final morphology of the granules also affects their related properties: the surface of the granules containing the modified starch N-zorbit M is smooth, suggesting good fluidity; the wrinkles on the surface of the granules containing maltodextrin National M1 increase friction and collisions between the granules, reducing the granule fluidity; and although the surface of the granules containing porous starch is smooth, the bowl-shaped morphology may cause the granules to mechanically lock with each other, resulting in reduced fluidity.

[0083] Test Example 4

[0084] The tap density results of the Noni enzyme microcapsules prepared by Examples 1 to 8 and Comparative Examples 1 to 4 are shown in FIG4 . It can be seen from the figure that the tap density of the Noni enzyme microcapsules with different solid loadings is different. Under the condition of an inlet air drying temperature of 150°C, the tap density of the microcapsules with a low solid loading (25%) of the same wall material is significantly greater than the tap density of the microcapsules with a high solid loading (40%) (p < 0.05). This is because the droplets with a lower solid loading can form smaller dry particles when drying. However, under the drying temperature of 190°C, the difference in tap density between different solid loadings is not significant (p > 0.05). The reason for this may be that the increase in drying temperature further reduces the water content of the microcapsules, and the dry particles with a high solid loading further shrink, resulting in a smaller difference in tap density between different solid loadings. This also resulted in the tap density of dried microcapsules with the same wall material and solid loading being significantly higher at 190°C than at 150°C (p < 0.05). The tap density of dried microcapsules with different wall materials also varied, with those with porous starch walls showing significantly higher tap density than those with National M1 maltodextrin (p < 0.05). Observations of the particle microstructure suggest that this is because the surface of the National M1 maltodextrin group exhibited more and deeper wrinkles than the porous starch group. More severe surface wrinkles increase the gaps between particles, leading to a lower packing density. Furthermore, the porous starch group had a lower initial solids content in the droplets during drying, resulting in smaller dried particles compared to National M1 maltodextrin and modified starch N-zorbit M.

[0085] Test Example 4

[0086] The total polyphenol content (TPC) of the microcapsules in Examples 1 to 8 is shown in Figures 5 and 6. As can be seen from the figures, when the noni enzyme was dried at a drying temperature of 150°C, the TPC content of the maltodextrin National M1 (25%), modified starch N-zorbit M (25%), and porous starch (25%) sample groups increased significantly after spray drying (p < 0.05). However, the TPC content of the (40%), modified starch N-zorbit M (40%), and porous starch (40%) sample groups did not increase significantly (p > 0.05). However, when dried at a drying temperature of 190°C, the TPC content of all sample groups increased significantly (p < 0.05).

[0087] Experimental results showed that spray drying significantly increased the TPC of noni enzyme at a higher drying temperature (190°C) (p < 0.05). The higher the drying temperature, the greater the increase in phenolic content. This is because phenolic compounds are generally less susceptible to thermal decomposition and more thermally stable than most bioactive compounds (such as vitamin C). Furthermore, they may be transformed after drying, becoming more soluble or more soluble in the extraction solvent, leading to an increase in the TPC of the reconstituted solution. During the spray drying process, noni enzyme is exposed to high temperatures. The heat energy provided by these conditions may cleave the glycosidic bonds of the phenolic sugars within the noni enzyme, producing phenolic glycosides. These phenolic glycosides also react with the Folin-phenol reagent in the TPC test, resulting in an increase in the TPC value. Furthermore, at 190°C, polyphenol aggregation and synthesis may occur, which also increases the TPC value.

[0088] Test Example 5

[0089] As shown in Figures 7 and 8, the experimental results show that when spray-dried at a drying temperature of 150°C, the total antioxidant capacity (TAC) of the maltodextrin National M1 and modified starch N-zorbit M samples significantly increased after spray drying (p < 0.05), while the TAC value of porous starch did not increase significantly (p > 0.05). However, when dried at a drying temperature of 190°C, the TAC values ​​of the maltodextrin National M1 (25%) and modified starch N-zorbit M (40%) samples did not increase significantly (p > 0.05). The experimental results show that at an inlet air drying temperature of 150°C, the TAC values ​​of the noni enzyme using maltodextrin National M1 and modified starch N-zorbit M as wall materials increased significantly after spray drying (p < 0.05).

[0090] The present invention utilizes modified starch N-zorbit M and porous starch as wall materials to encapsulate noni enzyme and spray-dry the resulting high-load starch-based, stable noni enzyme spray-dried microcapsules. This helps extend the shelf life of noni enzyme, enabling better industrial applications. The microcapsules mask odors, retain phenolic active substances, and enhance antioxidant capacity. Using only one spray-drying step reduces operating costs and improves the quality of the noni enzyme spray-dried microcapsules.

[0091] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A high-load starch-based stable noni enzyme spray-dried microcapsule, characterized in that: The high-load starch-based stable noni enzyme spray-dried microcapsules include noni enzyme and starch matrix.

2. The high-load starch-based stable noni enzyme spray-dried microcapsules according to claim 1, characterized in that: The noni enzyme is obtained by fermenting noni fruit.

3. The high-load starch-based stable noni enzyme spray-dried microcapsules according to claim 1, characterized in that: The starch matrix includes but is not limited to any one of modified starch N-zorbit M and porous starch.

4. The high-load starch-based stable noni enzyme spray-dried microcapsules according to claim 1, characterized in that: The modified starch N-zorbit M sample solution is obtained by mixing noni enzyme and modified starch N-zorbit M; the porous starch sample solution is obtained by heating and mixing noni enzyme and porous starch.

5. The method for preparing high-load starch-based stable noni enzyme spray-dried microcapsules according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Noni enzyme is mixed with modified starch N-zorbit M and stirred until the wall material is completely dissolved, and the resulting solution is the modified starch N-zorbit M sample solution; (2) Noni enzyme is mixed with porous starch, stirred, and heated until the wall material is completely dissolved, and the resulting solution is the porous starch sample solution; (3) The mixed solution obtained in steps (1), (2), and (3) is spray-dried to obtain high-load starch-based stable Noni enzyme spray-dried microcapsules.

6. The preparation method according to claim 5, characterized in that: The mixing of the noni enzyme and the modified starch N-zorbit M in step (1) has a solid content of 10% to 50%; the stirring speed in step (1) is 500-1200 rpm / min.

7. The preparation method according to claim 5, characterized in that: The mixing of the noni enzyme and the porous starch in step (2) has a solid content of 10% to 50%; the stirring speed in step (2) is 500-1200 rpm / min.

8. The preparation method according to claim 5, characterized in that: The feed creep speed of the spray drying in step (3) is 5-20 rpm, the inlet air temperature of the spray drying is 120-160°C, and the spray drying time is 3-8 min.

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