Hollow salt microsphere, preparation method and application

Abstract

The invention discloses a hollow salt microsphere as well as a preparation method and application thereof. The preparation method of the hollow salt microspheres comprises the following steps: mixing nano starch particles, sodium chloride crystals, water and oil, homogenizing to form a Pickering emulsion, and carrying out spray drying to prepare the hollow salt microspheres with the particle size of 180-360nm. According to the preparation method provided by the invention, the self-assembly performance of the nano starch is utilized to stabilize the NaCl oil-in-water Pickering emulsion, so that the construction of the hollow salt microspheres is realized. The particle size of the prepared hollow salt microspheres reaches the nanometer level, the particle size is small, the hollow salt microspheres can be rapidly dissolved in oral saliva, salty taste is generated, and the effects of reducing salt and increasing salty taste are achieved.

Description

Technical Field

[0001] The invention belongs to the field of edible salt and relates to a hollow salt microsphere, a preparation method and an application. Background Art

[0002] A high-salt diet can easily induce high blood pressure and increase the risk of cardiovascular diseases (heart disease, hypertension, stroke, etc.). Salty foods in snack foods account for about 1 / 3 of the market size of the snack food industry. Therefore, proposing an effective salt reduction strategy for salty snack foods is not only a health appeal for the whole people, but also the basis for the vigorous development of related industries. At present, salty snack foods mainly reduce salt through NaCl crystal micro-crystal miniaturization technology (such as ultrasound-assisted anti-solvent crystallization, spray drying, electrofluid atomization drying, foam pad drying and other technologies to prepare NaCl nano-micro crystals), NaCl substitute screening (KCl, yeast extract, etc.) and consumer health cognition adjustment. The particle size of salt particles significantly affects its salty taste perception. Larger salt particles dissolve and release more slowly in the mouth, resulting in poor salty taste perception. Especially in solid low-moisture foods, up to 70-95% of salt crystals cannot be released before swallowing. In contrast, smaller salt particles can release sodium ions from the matrix faster, thereby improving the efficiency of salty taste perception. Summary of the invention

[0003] The particle size of edible salt obtained by the current preparation method is at the micron level, which is relatively large and affects the salt reduction effect.

[0004] In view of the problem that the edible salt obtained by the current preparation method has a large particle size, which affects the salt reduction effect, a hollow salt microsphere, a preparation method and an application are provided.

[0005] In some embodiments, a method for preparing hollow salt microspheres is provided, comprising the following steps:

[0006] Nano starch particles, sodium chloride crystals, water and oil are mixed, homogenized to form a Pickering emulsion, and spray-dried to prepare the hollow salt microspheres with a particle size of 180nm to 360nm.

[0007] In some embodiments, the method for preparing hollow salt microspheres provides one or more of the following characteristics:

[0008] The mass volume ratio of the sodium chloride crystals to the water is (0.5-1) g:100 mL;

[0009] The mass ratio of the sodium chloride crystals to the nano starch particles is (0.5-1): 0.1;

[0010] The mass ratio of the oil to the nano starch particles is (1~2):1.

[0011] In some embodiments, the method for preparing hollow salt microspheres provides one or more of the following characteristics:

[0012] The starch in the nano starch particles comprises one or more of cereal starch, tuber and root starch, legume starch, tropical crop starch, nut starch and algae starch;

[0013] The oil comprises one or more of plant oil, animal oil and algae oil;

[0014] The homogenization is carried out at a rotation speed of 12000 r / min to 20000 r / min.

[0015] In some embodiments, the method for preparing hollow salt microspheres provides one or more of the following characteristics:

[0016] The particle size of the Pickering emulsion is 2 μm to 980 μm;

[0017] The particle size of the nano starch particles is 50nm~200nm.

[0018] In some embodiments, the preparation method of hollow salt microspheres provided, the preparation method of the nano starch particles comprises the following steps: gelatinizing starch in the presence of a buffer solution with a pH value of 4.5 to 6 to prepare gelatinized starch, treating the gelatinized starch with a debranching enzyme, separating the solid from the liquid, and recrystallizing and drying the obtained supernatant to prepare the nano starch particles;

[0019] Optionally, the method for preparing the nano starch particles satisfies one or more of the following characteristics:

[0020] In the step of gelatinizing the starch, the concentration of the starch is 0.05 g / mL to 0.2 g / mL based on the amount of feed;

[0021] In the step of gelatinizing the starch, the gelatinization is carried out by heating in a boiling water bath for 20 minutes to 60 minutes under stirring;

[0022] The debranching enzyme comprises one or more of glucoamylase, glycogen debranching enzyme, and starch debranching enzyme; alternatively, the starch debranching enzyme comprises one or more of pullulanase and isoamylase;

[0023] In the step of treating the gelatinized starch with a debranching enzyme, the gelatinized starch is treated with a debranching enzyme at 40° C. to 60° C. for 5 h to 10 h;

[0024] After the step of treating the gelatinized starch with a debranching enzyme, the method further comprises heating the reaction product at 90° C. to 100° C. for 30 min to 60 min to inactivate the debranching enzyme;

[0025] The supernatant is allowed to stand at 0°C to 10°C for 5h to 20h for the recrystallization.

[0026] In some embodiments, the method for preparing hollow salt microspheres provides one or more of the following characteristics:

[0027] The inlet air temperature of spray drying is 130℃~160℃;

[0028] The outlet air temperature of spray drying is less than or equal to 80 ℃;

[0029] The pressure of spray drying is 0.1Mpa~0.3Mpa;

[0030] The liquid delivery rate for spray drying is 10 mL / min~13 mL / min;

[0031] The drying air volume of spray drying is 0.05 m 3 / min~0.1 m 3 / min.

[0032] In some embodiments, a hollow salt microsphere is provided, which is prepared by the preparation method.

[0033] In some embodiments, the particle size of the hollow salt microspheres is 180 nm to 360 nm.

[0034] In some embodiments, hollow salt microspheres are provided that meet one or more of the following characteristics:

[0035] In the hollow salt microspheres, the mass percentage of C element is 26% to 27%, the mass percentage of O element is 3% to 4%, the mass percentage of Na element is 41% to 42%, and the mass percentage of Cl element is 28% to 29%;

[0036] The hollow salt microspheres are porous structures.

[0037] In some embodiments, there is provided a use of at least one of the hollow salt microspheres prepared by the preparation method and the hollow salt microspheres in preparing seasonings or foods. Optionally, the food is a solid food.

[0038] The preparation method provided above utilizes the self-assembly property of nano starch to stabilize the NaCl water-in-oil Pickering emulsion to achieve the construction of hollow salt microspheres. The prepared hollow salt microspheres have a particle size of nanometer level, are small in size, can be quickly dissolved in oral saliva, produce salty taste, and achieve the effect of reducing salt and increasing saltiness. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the implementation methods and examples of the present application and to more completely understand the present application and its beneficial effects, the following is a brief introduction to the drawings required for use in the description of the implementation methods or examples. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0040] Figure 1 is a diagram of the formation mechanism of hollow salt microspheres in one embodiment;

[0041] Figure 2 The morphology of starch nanoparticles and pregelatinized waxy corn starch in Example 1, wherein A is a scanning electron microscopy result of pregelatinized waxy corn starch, and B is a scanning electron microscopy result of starch nanoparticles;

[0042] Figure 3 This is the distribution diagram of starch nanoparticle size in Example 1;

[0043] Figure 4 The results of characterization of the Pickering emulsion in Example 1 are shown in Figure A, wherein Figure A is a laser confocal scanning result; Figure B is an optical microscope observation result;

[0044] Figure 5 is a particle size distribution diagram of the oil-in-water Pickering emulsion in Example 1;

[0045] Figure 6 The scanning electron microscopy test results of commercially available edible salt and hollow salt microspheres in Example 1, wherein A is the scanning electron microscopy result of commercially available edible salt, and B is the scanning electron microscopy result of hollow salt microspheres;

[0046] Figure 7 The transmission electron microscopy results of the hollow salt microspheres in Example 1;

[0047] Figure 8 The results of elemental analysis of the hollow salt microspheres in Example 1, wherein A is a scanning electron microscope image of the hollow salt microspheres, and B is an elemental point analysis image of the hollow salt microspheres;

[0048] Fig. 9 The particle size distribution result of the hollow salt microspheres in Example 1;

[0049] Fig.10 This is a morphology of the hollow salt formed by the nanoemulsion prepared with the soapberry saponin emulsifier in Comparative Example 1;

[0050] Fig.11 This is the morphology of the hollow salt using chitosan & acid as carrier in Comparative Example 2;

[0051] Fig.12 This is the morphology of the hollow salt formed using gum arabic as the raw material in Comparative Example 3;

[0052] Fig.13 It is a scale diagram of the gLMS saltiness intensity scaling method in the application example;

[0053] Fig.14 These are the result graphs of the saltiness evaluation of the sample group and the control group in the application example, where Figure A is a frequency graph for qualitatively evaluating the saltiness of the sample group and the control group, and Figure B is a scoring result graph for quantitatively describing the saltiness intensity of the sample group and the control group. DETAILED DESCRIPTION

[0054] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0055] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0056] the term

[0057] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0058] In the present application, "plurality", "multiple", "multiple times", "multiples", etc., unless otherwise specified, refer to a number greater than 2 or equal to 2. For example, "one or more" means one or greater than or equal to two.

[0059] The terms "combination thereof", "any combination thereof", "any combination thereof" and the like used in this application include all suitable combinations of any two or more of the listed items.

[0060] In this application, the "suitable" mentioned in "suitable combination", "suitable method", "any suitable method", etc. is based on the ability to implement the technical solution of this application, solve the technical problems of this application, and achieve the expected technical effects of this application.

[0061] In the present application, "preferred", "better", "more preferred" and "suitable" are only used to describe implementation methods or examples with better effects. It should be understood that they do not constitute limitations on the scope of protection of the present application.

[0062] In the present application, "further", "further", "particularly" and the like are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of the present application.

[0063] In this application, "optionally", "optional", and "optional" mean optional or dispensable, that is, any one of the two parallel schemes of "yes" or "no". If multiple "options" appear in a technical solution, unless otherwise specified and there is no contradiction or mutual restriction, each "optional" is independent.

[0064] In the present invention, in the "first aspect", "second aspect", "third aspect", "fourth aspect", etc., the terms "first", "second", "third", "fourth", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first", "second", "third", "fourth", etc. only serve the purpose of non-exhaustive enumeration and description, and it should be understood that they do not constitute a closed limitation on quantity.

[0065] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0066] In the present application, when it comes to numerical intervals (i.e., numerical ranges), unless otherwise specified, the optional numerical distribution is considered continuous within the above numerical interval, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical range, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to the integers within the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints. In this article, it is equivalent to directly listing each integer, such as t is an integer selected from 1 to 10, indicating that t is any integer selected from the group of integers consisting of 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10. In addition, when multiple ranges are provided to describe features or characteristics, these ranges can be combined. In other words, unless otherwise specified, the ranges disclosed herein should be understood to include any and all subranges included therein.

[0067] The temperature parameters in this application, unless otherwise specified, are allowed to be either constant temperature treatment or to vary within a certain temperature range. It should be understood that the constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within the range of ±5°C, ±4°C, ±3°C, ±2°C, and ±1°C are allowed.

[0068] In the present application, % (w / w) and wt% both represent weight percentage, % (v / v) refers to volume percentage, and % (w / v) refers to mass volume percentage.

[0069] The "room temperature" in this application generally refers to 5°C to 30°C, preferably 25±5°C.

[0070] The particle size of salt particles significantly affects their salty taste perception. Larger salt particles dissolve and release more slowly in the mouth, resulting in poor salty taste perception. Especially in solid low-water content foods, up to 70-95% of salt crystals cannot be released before swallowing. In contrast, smaller salt particles are able to release sodium ions from the matrix faster, thereby improving the efficiency of salty taste perception.

[0071] The edible salt prepared by the current preparation method has a large particle size and does not reach the nanometer level, and the salt reduction effect is poor. Some edible salt preparation systems add acid and chitosan, which will produce sour and astringent tastes, affect the flavor, and reduce consumer acceptance.

[0072] In some embodiments, a method for preparing hollow salt microspheres is provided, comprising the following steps:

[0073] Nano starch particles, sodium chloride crystals, water and oil are mixed, homogenized to form a Pickering emulsion, and spray dried to prepare hollow salt microspheres with a particle size of 180nm~360nm. For example, the prepared hollow salt microspheres have a particle size of 180nm, 190nm, 200nm, 210nm, 220nm, 230nm, 240nm, 250nm, 260nm, 270nm, 280nm, 290nm, 300nm, 310nm, 320nm, 330nm, 340nm, 350nm, 360nm, etc. or a range consisting of any two of the foregoing values.

[0074] During the preparation process, first, the self-assembly property of nano starch can stabilize the NaCl water-in-oil Pickering emulsion, and the NaCl water-in-oil Pickering emulsion is atomized to form fine droplets through spray drying. The water in the droplets evaporates rapidly during the drying process, and the salt crystals are concentrated on the surface of the droplets to form a solid shell layer, and finally a hollow salt microsphere with a hollow structure composed of NaCl crystals is formed. The formation mechanism of hollow salt microspheres is as follows Figure 1 shown.

[0075] Hollow salt microspheres are prepared by utilizing the self-assembly properties of nano-starch. On the one hand, starch is green and economical, has certain biocompatibility, and is harmless to the human body. The hollow structure spontaneously formed by starch nanoparticles has load-bearing capacity and does not bring in any flavor other than salty taste, which greatly improves consumer acceptance and enhances the perception of salty taste.

[0076] In some embodiments, in the preparation method of hollow salt microspheres provided, the mass volume ratio of sodium chloride crystals to water is (0.5~1) g:100 mL. For example, the mass volume ratio of sodium chloride crystals to water can be 0.5 g:100 mL, 0.5 g:100 mL, 0.6 g:100 mL, 0.7 g:100 mL, 0.8 g:100 mL, 0.9 g:100 mL, 1 g:100 mL or a range selected from any two of the foregoing ratios.

[0077] In some embodiments, in the preparation method of hollow salt microspheres provided, the mass ratio of sodium chloride crystals to nano starch particles is (0.5~1):0.1. For example, the mass ratio of sodium chloride crystals to nano starch particles can be 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1 or a range selected from any two of the foregoing ratios.

[0078] In some embodiments, in the preparation method of hollow salt microspheres provided, the mass ratio of oil to nano starch particles is (1~2):1, for example, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, 2:1 or a range selected from any two of the foregoing ratios.

[0079] It can be understood that in some embodiments, in the method for preparing hollow salt microspheres provided, the starch used to prepare nano starch particles includes one or more of the natural starches existing in all plants and microorganisms in nature.

[0080] In some embodiments, the preparation method of hollow salt microspheres provided, the starch in the nano starch particles comprises one or more of cereal starch, tuber and root starch, bean starch, tropical crop starch, nut starch and algae starch. In some embodiments, cereal starch comprises one or more of corn starch, wheat starch, rice starch, sorghum starch, oat starch, barley starch and buckwheat starch. In some embodiments, tuber and root starch comprises one or more of potato starch, cassava starch, sweet potato starch, yam starch, taro starch, Jerusalem artichoke starch and lotus root starch. In some embodiments, bean starch comprises one or more of pea starch, mung bean starch, chickpea starch, red bean starch and soybean starch. In some embodiments, tropical crop starch comprises one or more of water chestnut starch, sago starch and banana starch. In some embodiments, nut starch comprises chestnut starch. In some embodiments, algae starch comprises spirulina starch.

[0081] In some embodiments, in the preparation method of hollow salt microspheres provided, the starch in the nano starch particles comprises one or more of corn starch, chestnut starch, bean starch, potato starch, sweet potato starch, potato starch, cereal starch, wheat starch, water chestnut starch, and lotus root starch.

[0082] It can be understood that, in some embodiments, in the method for preparing hollow salt microspheres provided, the oil includes one or more of all edible natural oils.

[0083] In some embodiments, the preparation method of hollow salt microsphere provided, oil comprises one or more of vegetable oil, animal oil and algae oil. In some embodiments, vegetable oil comprises one or more of corn oil, rice bran oil, peanut oil, walnut oil, almond oil, hazelnut oil, pine nut oil, soybean oil, rapeseed oil, sunflower seed oil, sesame oil, cottonseed oil, pumpkin seed oil, grape seed oil, olive oil, coconut oil, palm oil, avocado oil, safflower oil, tea seed oil, sunflower seed oil, castor oil, cocoa butter and shea butter. In some embodiments, animal oil comprises one or more of lard, tallow, mutton fat, chicken fat, duck fat, goose fat, fish oil, whale oil, butter and ghee.

[0084] In some embodiments, in the method for preparing hollow salt microspheres provided, the oil comprises one or more of sunflower oil, olive oil, soybean oil, corn oil, rapeseed oil, grape seed oil, linseed oil, peanut oil, and safflower oil.

[0085] In some embodiments, the preparation method of hollow salt microspheres provided is homogenized at a speed of 12000 r / min to 20000 r / min. For example, the speed for homogenization can be 12000 r / min, 13000 r / min, 14000 r / min, 15000 r / min, 16000 r / min, 17000 r / min, 18000 r / min, 19000 r / min, 20000 r / min, etc. or a range consisting of any two of the foregoing values.

[0086] In some embodiments, in the preparation method of hollow salt microspheres provided, the particle size of the Pickering emulsion can be 2 μm to 980 μm, for example, 2 μm, 10 μm, 50 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 980 μm, etc., or a range consisting of any two of the foregoing values.

[0087] When Pickering emulsions are spray-dried to prepare hollow salts, the stability and uniformity of the Pickering emulsions have an important influence on the formation and effect of hollow salt particles. First, the stability of the Pickering emulsion determines whether a complete and uniform hollow structure can be formed during the spray drying process. If the emulsion is unstable, the oil droplets are easy to merge, resulting in the failure of the spray-dried particles to form an ideal hollow structure. This situation will reduce the specific surface area of ​​the hollow salt, affect the release rate of sodium ions, and thus reduce the perception of saltiness. Second, the uniformity of the Pickering emulsion is crucial to the size and structural consistency of the final particles. A uniform emulsion can ensure that the oil droplets are of uniform size and form hollow salt particles with uniform particle size after spray drying, thereby improving the stability of the product and the uniformity of saltiness perception. If the emulsion is not uniform, the particles after spray drying will have large size and morphological differences, affecting the dissolution rate of the hollow salt and the overall sensory experience.

[0088] During the spray drying process, Pickering emulsions with larger particle sizes will lead to uneven internal structures of the formed particles, uneven wall thickness distribution, and even the failure to form an ideal hollow structure. This irregular structure leads to a decrease in the solubility of the hollow salt and the release rate of sodium ions, thereby affecting the perceived intensity and uniformity of the salty taste. Secondly, the uniformity of the emulsion directly affects the uniformity of the hollow salt particles. Emulsion particles with larger particle sizes are prone to forming uneven oil droplets, which in turn leads to different shapes of salt particles after spray drying. Poor uniformity of particles will lead to different dissolution rates of salt in the mouth, and the perceived intensity and time of saltiness will also differ, affecting the overall sensory experience of the product.

[0089] In some embodiments, the preparation method of hollow salt microspheres provided, the particle size of nano starch particles can be 50nm~200nm, for example, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, 160nm, 170nm, 180nm, 190nm, 200nm, etc. or a range consisting of any two of the foregoing values.

[0090] When using starch as an emulsifier to prepare Pickering emulsions, the particle size of the starch directly affects the stability and performance of the emulsion. Smaller starch particles are more helpful in stabilizing Pickering emulsions. This is because smaller particles can be more evenly adsorbed on the oil-water interface to form a stable particle layer, reducing the aggregation and merging of oil droplets. If the starch particles are too large, such as exceeding 10 microns, it is difficult to distribute evenly at the oil-water interface during the emulsion preparation process, which will result in low coverage at the interface and reduce the stability of the emulsion. Larger particles may also detach from the interface due to gravity sedimentation, resulting in emulsion stratification. Therefore, when using starch as an emulsifier for Pickering emulsions, select particles with a moderate particle size to ensure that they can effectively adsorb at the oil-water interface to form a stable physical barrier, thereby improving the stability and uniformity of the emulsion.

[0091] In some embodiments, the preparation method of hollow salt microspheres provided, the preparation method of nano starch particles comprises the following steps: in the presence of a buffer solution with a pH value of 4.5 to 6, for example, the pH value of the buffer solution can be 4.5, 5, 5.5, 6, etc. or a range composed of any two of the foregoing values, gelatinizing starch to prepare gelatinized starch, treating the gelatinized starch with a debranching enzyme, separating the solid from the liquid, recrystallizing the obtained supernatant, and drying to prepare nano starch particles.

[0092] In some embodiments, in the method for preparing hollow salt microspheres and the method for preparing nano starch particles provided, in the step of gelatinizing the starch, the concentration of the starch is 0.05 g / mL to 0.2 g / mL, based on the amount of feed. For example, the concentration of the starch can be 0.05 g / mL, 0.06 g / mL, 0.07 g / mL, 0.08 g / mL, 0.09 g / mL, 0.10 g / mL, 0.11 g / mL, 0.12 g / mL, 0.13 g / mL, 0.14 g / mL, 0.15 g / mL, 0.16 g / mL, 0.17 g / mL, 0.18 g / mL, 0.19 g / mL, 0.20 g / mL, or a range consisting of any two of the foregoing values.

[0093] In some embodiments, in the method for preparing hollow salt microspheres and the method for preparing nano starch particles provided, in the step of gelatinizing the starch, the starch is heated in a boiling water bath for 20 min to 60 min under stirring for gelatinization. For example, the heating time in the boiling water bath can be 20 min, 30 min, 40 min, 50 min, 60 min, etc. or a range consisting of any two of the foregoing values.

[0094] In some embodiments, in the method for preparing hollow salt microspheres and the method for preparing nano starch particles provided, the debranching enzyme comprises one or more of glucoamylase, glycogen debranching enzyme, and starch debranching enzyme.

[0095] In some embodiments, in the method for preparing hollow salt microspheres and the method for preparing nano starch particles provided, the starch debranching enzyme comprises one or more of pullulanase and isoamylase.

[0096] In some embodiments, in the method for preparing hollow salt microspheres and the method for preparing nano starch particles provided, in the step of treating gelatinized starch with a debranching enzyme, the gelatinized starch is treated with a debranching enzyme for 5 h to 10 h, for example, 5 h, 6 h, 7 h, 8 h, 9 h, 10 h, under conditions of 40°C to 60°C, for example, 40°C, 50°C, 60°C, etc. or within a range of any two of the foregoing numerical values.

[0097] In some embodiments, in the method for preparing hollow salt microspheres and the method for preparing nano starch particles provided, after the step of treating gelatinized starch with a debranching enzyme, the step further includes heating the reaction product at 90°C to 100°C for 30 min to 60 min to inactivate the debranching enzyme.

[0098] In some embodiments, in the method for preparing hollow salt microspheres and the method for preparing nano starch particles provided, the supernatant is allowed to stand at 0° C. to 10° C. for 5 h to 20 h for recrystallization.

[0099] In some embodiments, in the method for preparing hollow salt microspheres provided, the inlet air temperature of spray drying is 130°C to 160°C. For example, the inlet air temperature of spray drying can be 130°C, 140°C, 150°C, 160°C, etc. or a range consisting of any two of the foregoing values.

[0100] In some embodiments, in the method for preparing hollow salt microspheres provided, the outlet air temperature of the spray drying is less than or equal to 80°C.

[0101] In some embodiments, in the method for preparing hollow salt microspheres provided, the spray drying pressure is 0.1 MPa to 0.3 MPa. For example, the spray drying pressure can be 0.1 MPa, 0.2 MPa, 0.3 MPa, etc., or a range consisting of any two of the foregoing values.

[0102] In some embodiments, in the preparation method of hollow salt microspheres provided, the liquid delivery rate of spray drying is 10 mL / min~13 mL / min, for example, 10 mL / min, 11 mL / min, 12 mL / min, 13 mL / min, etc. or a range consisting of any two of the foregoing values.

[0103] In some embodiments, the method for preparing hollow salt microspheres provided, the dry air volume of the spray drying is 0.05m 3 / min~0.1m 3 / min, for example, the drying air volume for spray drying can be 0.05m 3 / min, 0.06m 3 / min, 0.07m 3 / min, 0.08m 3 / min, 0.09m 3 / min, 0.10m 3 / min, etc. or a range consisting of any two of the aforementioned values.

[0104] In some embodiments, a hollow salt microsphere is provided, which is prepared by the aforementioned preparation method.

[0105] In some embodiments, the particle size of the hollow salt microspheres is 180nm~360nm. For example, the particle size of the hollow salt microspheres can be 180nm, 190nm, 200nm, 210nm, 220nm, 230nm, 240nm, 250nm, 260nm, 270nm, 280nm, 290nm, 300nm, 310nm, 320nm, 330nm, 340nm, 350nm, 360nm, etc. or a range consisting of any two of the foregoing values.

[0106] The particle size of the hollow salt microspheres directly affects the contact area between the salt particles and saliva. If the particle size of the hollow salt microspheres is large, the advantages of their hollow structure are difficult to play, and thus the surface area cannot be effectively increased to promote the release of sodium ions, which reduces the dissolution rate of the hollow salt microspheres in the mouth and affects the overall salty taste perception effect.

[0107] Hollow salt microspheres prepared by self-assembling nano starch particles can quickly release salty taste in the mouth, increase the solubility of NaCl in saliva, and enhance the effect of salty taste perception. Sodium ions can be quickly released, improving salty taste perception.

[0108] The hollow salt microspheres provided have a small particle size and excellent uniformity and stability. The hollow salt microspheres with nano-scale particles significantly improve the solubility and dispersibility of salt, achieving faster and more efficient salt release in taste perception, providing scientific support for reducing salt usage while maintaining flavor.

[0109] In some embodiments, in the hollow salt microspheres provided, the mass percentage of the C element is 26% to 27%, the mass percentage of the O element is 3% to 4%, the mass percentage of the Na element is 41% to 42%, and the mass percentage of the Cl element is 28% to 29%;

[0110] In some embodiments, the hollow salt microspheres provided are porous structures.

[0111] The hollow salt microspheres provided have a unique hollow spherical porous structure with a cavity or partial cavity inside, which significantly reduces the overall density; at the same time, its surface is smooth and has a high porosity. This design not only increases the specific surface area of ​​the particles, but also accelerates the dissolution of salt, thereby significantly improving the efficiency of salty taste perception.

[0112] In some embodiments, there is provided a use of at least one of the hollow salt microspheres prepared by the aforementioned preparation method and the aforementioned hollow salt microspheres in preparing seasonings or foods.

[0113] In some embodiments, in the provided uses, the food is a solid food.

[0114] The method for preparing hollow salt microspheres provides a method for the first time of utilizing the self-assembly performance of nano starch to stabilize the Pickering emulsion of NaCl and spray-drying the emulsion to form nano-scale hollow salt microsphere particles.

[0115] The hollow salt microspheres prepared by self-assembly of nano-starch increase the adhesion of NaCl on the surface of solid food, reduce loss, and achieve the best salt reduction effect.

[0116] The hollow salt microspheres provided above were prepared by using green and safe emulsifiers and economical and efficient preparation processes. Starch is used as an emulsifier. Compared with traditional emulsifiers (such as saponin), starch has the advantages of being green, safe, and low-cost, while simplifying the process of obtaining and using raw materials. In addition, the hollow salt is prepared using spray drying equipment. This method is safer and more economical than electrofluid atomization drying (the currently reported technology for preparing the smallest salt microsphere particle size) equipment, and is suitable for large-scale industrial production.

[0117] The hollow salt microspheres provided can significantly reduce the amount of salt in food. When applied to solid foods such as potato chips, the amount of salt can be reduced by 70% while maintaining the flavor and taste compared to ordinary edible salt. It can significantly reduce the health risks of high-salt foods and provide a new solution for the food industry that takes both flavor and health into consideration.

[0118] Pregelatinized waxy corn starch was purchased from Nantong Gaofeng Biotechnology Co., Ltd.; pullulanase was purchased from Cangzhou Xiasheng Enzyme Biotechnology Co., Ltd.; sodium dihydrogen phosphate was purchased from Henan Gaobao Industrial Co., Ltd.; baking soda was purchased from Angel Yeast Co., Ltd.; NaCl and commercially available edible salt were purchased from Jiangsu Salt Industry Group Co., Ltd.; blended oil was purchased from Shanghai Nissin Oil Co., Ltd.; Nile red was purchased from Shanghai MacLean Biochemical Technology Co., Ltd.

[0119] Example 1. Preparation of hollow salt microspheres

[0120] 1 Preparation and characterization of starch nanoparticles

[0121] 1.1 Preparation of starch nanoparticles by vacuum freeze drying

[0122] Weigh 12g of sodium dihydrogen phosphate and place it in 500mL of pure water. Mix well and use 0.1mol / L NaOH to prepare a phosphate buffer with a pH of 5.0. Weigh 50g of waxy corn starch in 500mL of phosphate buffer with a pH of 5.0 to prepare a waxy corn starch milk (m / V) with a concentration of 10%. Heat in a boiling water bath and stir for 30min to ensure that the starch is fully gelatinized. Remove and cool to 58℃, add 7.5mL of pullulanase solution, place the gelatinized starch solution in a constant temperature water bath at 58℃ for 6h, take it out and heat at 100℃ for 30min to terminate the reaction. Centrifuge at 3000r / min for 15min to separate and remove the precipitate, pour out the supernatant and cool to room temperature, then place it in a 4℃ refrigerator for 13h for recrystallization. The prepared solution containing the formed starch nanoparticles was pre-frozen in a −40°C refrigerator and then dried in a vacuum freeze dryer under the following freeze drying conditions: sample temperature 20°C, cold trap temperature −60°C, and vacuum degree 1 Pa. The formed starch nanoparticle powder was then stored in a sealed bottle at ambient temperature for further analysis.

[0123] 1.2 Structural characterization of starch nanoparticles

[0124] The morphology of the obtained starch nanoparticles and pregelatinized waxy corn starch was observed using a Hitachi S-4800 field emission scanning electron microscope. Figure 2 As shown, A is the scanning electron microscopy result of pregelatinized waxy corn starch, and B is the scanning electron microscopy result of starch nanoparticles. Figure 2It can be seen that after the gelatinized corn starch fully reacts with the enzyme, it finally forms nano- and micro-sized starch particles under the physical action of vacuum freeze drying. The obtained starch nanoparticles can be used to stabilize the NaCl water-in-oil Pickering emulsion, providing a relatively ideal structural basis for the formation of hollow salts.

[0125] 1.3 Starch nanoparticle size distribution

[0126] The particle size distribution of starch nanoparticles was measured using the British Malvern Panalytical ZS ZEN3600 nanoparticle size and Zeta potential analyzer. Figure 3 As shown. Figure 3 It can be seen that the particle size of the prepared starch nanoparticles is 50nm~200nm.

[0127] 2 Preparation and characterization of oil-in-water Pickering emulsions stabilized by starch nanoparticles

[0128] 2.1 Preparation of oil-in-water Pickering emulsions stabilized by starch nanoparticles

[0129] Weigh 0.5 g of NaCl and mix it with 100 mL of deionized water, and add 0.1 g of starch nanoparticles. Add 0.1 g of blending oil as the oil phase, and use a high-speed emulsifying disperser at 14000 r / min for 3 min to disperse the blending oil in the aqueous solution to obtain a Pickering emulsion.

[0130] 2.2 Microscopic observation of oil-in-water Pickering emulsion

[0131] (1) Laser confocal microscopy

[0132] The results were observed using a German Leica TCS SP8 laser confocal scanning microscope. 1 / 12 (v / v) Nile red (0.01% anhydrous ethanol, w / v) staining solution was mixed evenly with 0.1 g blending oil, added to the prepared 100 mL salt solution dispersed with starch nanoparticles, and homogenized at 14000 r / min for 3 minutes using a German Aika T 25 D S25 high-speed emulsifier disperser. The emulsion was dropped on a glass slide with a pipette, and a cover glass was clamped with tweezers, one end of which was placed on the emulsion. The cover glass was slowly laid flat, and the emulsion on the surface of the glass slide and cover glass was wiped dry with filter paper, and then observed on the machine at 40 times. The excitation wavelength of Nile red is 488 nm, and the emission wavelength is 553~593 nm. The image was observed and taken. The results are as follows Figure 4 As shown in A.

[0133] (2) Optical microscope observation

[0134] The microscopic morphology of Pickering emulsion was observed using an EI optical microscope from Nanjing Jiangnan Yongxin Optical Co., Ltd. The emulsion was dropped onto a glass slide using a pipette, and a cover glass was picked up with tweezers. One end of the cover glass was placed on the emulsion, and the cover glass was slowly laid flat to prevent bubbles from forming. The emulsion on the surface of the glass slide and cover glass was wiped dry with filter paper, and fixed on the stage. The sample was observed under an oil immersion microscope with a magnification of 40 times and a magnification of 100 times. The results are shown in Figure 1. Figure 4 As shown in B.

[0135] Depend on Figure 4 As shown in Figure A, through laser confocal microscopy, it was found that the Nile red dye solution was fluorescently labeled green at the corresponding excitation wavelength, and the emulsion was a stable water-in-oil system at the micron level, indicating that the starch nanoparticles have interface effects and small size effects, and can be stably adsorbed at the oil-water interface to form a water-in-oil Pickering emulsion. At the same time, it can be observed that the emulsion droplets are of different sizes, and some droplets have a larger particle size. The reason may be that the liquid carried on the glass slide has a certain thickness, and these droplets are not on the same layer of the liquid. The relative particle size is larger when it is close to the lens, and smaller when it is far away from the lens; it may also be that the emulsion is rough and the droplet size distribution is wider. Figure 4 As shown in Figure B, the emulsion is in a uniform state through optical microscopy observation, the droplets are evenly distributed, and the emulsion droplets are micrometer-sized and relatively stable, which is consistent with the results of laser confocal microscopy observation, and there is a phenomenon that some droplets are larger in size.

[0136] 2.3 Particle size analysis of oil-in-water Pickering emulsions

[0137] The particle size of the NaCl water-in-oil Pickering emulsion stabilized by starch nanoparticles was measured by the British Malvern Mastersizer 3000 laser nanoparticle size analyzer. The results are as follows: Figure 5 As shown. Figure 5 It can be found that the particle size of the emulsion is mainly concentrated in 2~45 μm and 300~980 μm, which belongs to microemulsion.

[0138] 3 Preparation and characterization of hollow salt microspheres

[0139] 3.1 Preparation of hollow salt microspheres

[0140] The prepared Pickering emulsion was spray dried using a Yamato ADL311 spray dryer. Clean all parts of the spray drying equipment, install the spray chamber, cyclone separator and collection bottle in order, connect the feed pipe to the peristaltic pump, install the spray gun, connect the feed pipe, air inlet pipe and needle air pipe; turn on the power, turn on the pump switch and the pump gate, turn on the leakage protection switch, turn on the equipment, select the parameter settings, where the inlet temperature of the spray drying equipment is 150℃ and the outlet temperature is lower than 80℃; start the air compressor, fan and heater, and after the inlet temperature stabilizes at the set temperature, start the needle and peristaltic pump, set the pressure to 0.15 Mpa, the average liquid delivery volume to 11.3 mL / min, and the average dry air volume to 0.07 m 3 / min. After a period of time, hollow salt microspheres were obtained, which were collected and stored in a centrifuge tube.

[0141] 3.2 Structural characterization of hollow salt microspheres

[0142] (1) Scanning electron microscopy observation of hollow salt microspheres

[0143] The hollow salt microspheres were observed using a ZEISS Gemini 300 field emission scanning electron microscope. Commercially available edible salt and the prepared hollow salt microsphere samples were placed on a sample stage evenly covered with conductive glue, and the excess sample was blown off with an ear-cleaning bulb. The sample stage was then placed in an ion sputtering instrument for gold spraying. After the gold spraying was completed, the scanning electron microscope was used for observation. The working voltage of the scanning electron microscope was 10 kV. The results of the scanning electron microscope observation are shown in the figure. Figure 6 As shown, A is the result of scanning electron microscopy of commercially available edible salt, and B is the result of scanning electron microscopy of hollow salt microspheres.

[0144] pass Figure 6 From the results shown, it can be seen that the hollow salt microspheres provided have a smaller particle size than commercially available salt. The particle size of the hollow salt microspheres provided has reached the nanometer level, with a particle size of about 270.13±89.49nm. The hollow salt microspheres provided have a porous structure, which not only increases its surface area, but also when combined with saliva, the saliva can pass through the pore structure and quickly enter the interior of the hollow salt, thereby achieving the purpose of rapid dissolution and producing a stronger and faster salty taste intensity.

[0145] (2) Transmission electron microscopy observation of hollow salt microspheres

[0146] The prepared hollow salt microspheres were observed by transmission electron microscopy. Figure 7 As shown. Figure 7 It can be seen that the prepared hollow salt microspheres have a hollow spherical structure.

[0147] (3) Elemental analysis of hollow salt microspheres

[0148] The elements of the hollow salt microspheres were analyzed using an OXFORD Xplore 30 spectrometer. Energy dispersive spectroscopy (EDS) can be used for micro-area component analysis and is usually used in conjunction with a scanning electron microscope. High-speed electrons impact the sample surface to produce a characteristic X-ray continuum. EDS uses the position of the characteristic X-ray line peak to determine the type of element. After setting the parameters, start the EDS external control, use element point analysis, obtain the element distribution results, and then conduct a qualitative analysis of the elemental composition of the sample surface. The results are as follows: Figure 8 As shown. Among them, Figure 8 A in the figure is a scanning electron microscope image of the hollow salt microspheres, and B is an element point analysis image of the hollow salt microspheres. Through elemental analysis, the mass percentage of C element in the prepared hollow salt microspheres is 26.73%, the mass percentage of O element is 3.77%, the mass percentage of Na element is 41.23%, and the mass percentage of Cl element is 28.27%. It can be judged that the elements on the surface of the hollow salt microspheres are mainly composed of Na and Cl, so they are NaCl crystals, and there are a certain amount of C and O elements, which are presumed to be starch nanoparticles.

[0149] (4) Particle size analysis of hollow salt microspheres

[0150] The particle size of the hollow salt microspheres was measured by Malvern ZS ZEN3600 nanoparticle size and Zeta potential analyzer. Fig. 9 shown. Fig. 9 The results show that the average particle size of the hollow salt microspheres is about 270.13±89.49 nm, which is relatively small.

[0151] The above characterization results show that hollow salt microspheres were successfully constructed based on self-assembled starch nanoparticles by spray drying.

[0152] Comparative Example 1

[0153] (1) Preparation of nanoemulsion

[0154] The nanoemulsion template was prepared by ultrasonic one-pot method: 10% lemon oil or garlic oil and 1.5% quince saponin were added into a 20 mL vial together with deionized water, and then ultrasonicated at 20 kHz and 80% interval for 5 min in an ice bath environment, with the ultrasonic head of 95 mm and the power of 70% (280 W); the ultrasonic probe was inserted 40 mm below the liquid surface.

[0155] (2) Preparation of hollow salt microspheres

[0156] Accurately weigh 25 g of edible salt and the flavor oil nanoemulsion (1%) prepared in (1) into a beaker, add deionized water to 100 g, and stir and disperse for 30 min. Then use a micro spray dryer to spray dry, where the inlet temperature is 150 ° C, and the outlet temperature is controlled to be lower than 75 ° C by the flow rate. After collection, put it into a sealed polyethylene bottle.

[0157] (3) Morphology observation

[0158] Scanning electron microscopy (SEM): The SEM was observed using a German ZEISS Merlin field emission SEM. A small amount of powder sample was fixed on the sample stage with conductive glue, and the excess powder was blown off with an ear bulb. After gold spraying, it was placed in a field emission SEM for observation. The results are shown in the figure. Fig.10 shown.

[0159] Comparative Example 2

[0160] (1) Preparation of chitosan

[0161] The shrimp powder was repeatedly treated with 2N HCl for about 2 h to remove CaCO 3 , until CO is no longer observed 2 Production. Wash the shrimp powder and soak it in 2 N NaOH (shrimp powder: NaOH = 1:10) for 1 hour (80°C) to hydrolyze the shell protein. Then wash the treated shrimp powder and soak it in 1% potassium manganate at room temperature for 1 hour to remove astaxanthin. Soak the powder in 1% oxalic acid at 80°C for 1 hour to remove excess potassium manganate. Subsequently, wash and dry the powder to obtain chitin.

[0162] The prepared chitosan was mixed with 50% NaOH at a ratio of 1:10 and incubated at 100°C for 3 h. After 1.5 h of hot alkaline treatment, the alkalinity was replaced with fresh 50% NaOH. Finally, it was rinsed with water until neutral and dried at 50°C to obtain chitosan.

[0163] (2) Preparation of hollow salt microspheres

[0164] 5 g chitosan, 15 mL lactic acid and 485 mL water were mixed. After stirring for 24 h, 15 g NaCl was added to the chitosan / lactic acid solution, stirred for 2 h and then spray dried, wherein the solution was passed at a feed flow rate of 18.52 mL / min, 15,000 rpm, and the inlet and outlet temperatures were 140°C and 90°C, respectively, to finally form microparticles from the solution.

[0165] (3) Morphology observation

[0166] The spray-dried samples were firmly attached to the aluminum ingot using carbon gel. A gold coating machine (ion sputtering, Hitachi E-1010; Tokyo, Japan) was used to coat the samples with a 2 nm thick platinum film. Scanning electron microscopy was used for observation (Hitachi scanning electron microscope S-3400N; Tokyo, Japan). The results are shown in Fig.11 shown.

[0167] Comparative Example 3

[0168] A certain amount of salt and gum arabic (GA) were dispersed or dissolved in deionized water, stirred continuously for 60 min at room temperature to form a salt solution, and then spray dried. The inlet air temperature was 130°C, the salt concentration was 35% (m / V), the GA concentration was 0.50% (m / V), and the outlet air temperature was 80°C. By adjusting the ventilation volume, hollow salt microspheres were obtained.

[0169] The microstructure of the hollow salt microspheres was observed using a scanning electron microscope (SEM). A small amount of the product was evenly dispersed on a sample table with conductive glue, and then the excess product was blown away with an ear-cleaning bulb. The sample table was then placed in an ion sputtering instrument for gold spraying. The operating voltage of the scanning electron microscope was 10 kV. The results are shown in Figure 2. Fig.12 shown.

[0170] By comparison Figure 6 B and Figure 10~Figure 12 It can be seen that the hollow salt microspheres prepared in Example 1 have the following advantages compared to the hollow salts prepared in Comparative Examples 1 to 3: First, the particle size reaches the nanometer level, with a particle size of about 270.13±89.49nm, while the particle size of the hollow salts prepared in Comparative Examples 1 to 3 is at the micrometer level; secondly, the hollow salt microspheres prepared in Example 1 are porous structures, which not only increase their surface area, but also when combined with saliva, saliva can quickly enter the interior of the hollow salt through the pore structure, achieving the purpose of rapid dissolution and producing a stronger and faster saltiness intensity. Finally, Example 1 is the first time that nano starch is used to stabilize the Pickering emulsion of NaCl and spray-dry it to form hollow salt microsphere particles.

[0171] Application example: Hollow salt microspheres are used in salt-reduced potato chips

[0172] 1. Preparation of Potato Chips

[0173] Peel and wash the potatoes, steam them in a steamer, and then mash them into a paste. Take out an appropriate amount of mashed potatoes and put them into a beater for beating until they become a paste. Mix the mashed potatoes with the unbeaten mashed potatoes. After mixing, take out about 6 g of mashed potatoes by hand and knead them into balls for later use. On average, add 0.24 g of blending oil to every 6 g of mashed potatoes, press them into sheets with a pressing mold, and bake them in an oven after completion. The first baking temperature is 120 ℃ for the upper and lower tubes for 30 min. After baking, take them out, apply 0.3 g of blending oil to each potato chip, put them in the oven and set the upper and lower tube temperatures to 110 ℃ for 30 min. After completion, take them out, cool them to room temperature, and package them. A total of 60 potato chips were baked, and 30 potato chips were put into each bag. The potato chips in the control group were 51.99 g, and 0.800 g of salt was added; the potato chips in the sample group were 50.86 g, 70% of the salt was reduced, and 0.336 g of hollow salt microspheres were added. The bag was shaken manually for 5 min to mix well and then the sensory test was started.

[0174] 2. Sensory evaluation

[0175] Ten evaluators who had no recent cold, were in good health, were sensitive to salty taste, and had experience in sensory analysis were selected for the experiment. The saltiness intensity of the control and sample potato chips was determined using paired comparison tests and the gLMS intensity scale method. The test was repeated three times. During the test, the evaluators chewed the potato chips in their mouths for 30 seconds, rinsed their mouths before evaluating the next sample, and rested for 1 to 2 minutes. Statistical analysis was performed using the analysis of variance method. Fig.13 This is the scale diagram of the gLMS saltiness intensity scale. When evaluating samples, based on Fig.13 Saltiness was scored using the scale shown. Fig.14 The diagram is a result diagram of the saltiness evaluation of the sample group and the control group, wherein Diagram A is a frequency diagram for qualitatively evaluating the saltiness of the sample group and the control group, and Diagram B is a scoring result diagram for quantitatively describing the saltiness intensity of the sample group and the control group.

[0176] 3. Sensory evaluation results of potato chips

[0177] Depend on Fig.14 From A in the figure, we can see that in the paired comparison, 29 of the 30 participants thought that the potato chips sprinkled with hollow salt microspheres in the test sample were saltier, and 1 person thought that the potato chips sprinkled with table salt in the control sample were saltier. From the binomial distribution significance test table (α=0.05), we can see that 30 people participated in the evaluation, and the minimum number of affirmative answers required at the significance level of α≤0.05 is 21. Because 29>21, under α≤0.05, the test sample is saltier than the control sample. Therefore, the hollow salt microspheres are saltier than ordinary table salt when the salt reduction is 70%, and the saltiness intensity is higher; Fig.14From B, we can see that the saltiness intensity of potato chips sprinkled with hollow salt microspheres is 19.41, which is higher than the saltiness intensity of potato chips sprinkled with table salt (7.45), and there is a significant difference between the two when α=0.05. Therefore, when the salt reduction is 70%, the hollow salt microspheres are significantly saltier than table salt.

[0178] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0179] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims, and the description and drawings may be used to interpret the content of the claims.

Claims

1. A method for preparing hollow salt microspheres, characterized in that: The steps include: Nano starch particles, sodium chloride crystals, water and oil are mixed, homogenized to form a Pickering emulsion, and spray-dried to prepare the hollow salt microspheres with a particle size of 180nm to 360nm.

2. The preparation method according to claim 1, characterized in that: Meet one or more of the following characteristics: The mass volume ratio of the sodium chloride crystals to the water is (0.5-1) g:100 mL; The mass ratio of the sodium chloride crystals to the nano starch particles is (0.5-1): 0.1; The mass ratio of the oil to the nano starch particles is (1~2):

1.

3. The preparation method according to claim 1 or 2, characterized in that: Meet one or more of the following characteristics: The starch in the nano starch particles comprises one or more of cereal starch, tuber and root starch, legume starch, tropical crop starch, nut starch and algae starch; The oil comprises one or more of plant oil, animal oil and algae oil; The homogenization is carried out at a rotation speed of 12000 r / min to 20000 r / min.

4. The preparation method according to any one of claims 1 to 3, characterized in that Meet one or more of the following characteristics: The particle size of the Pickering emulsion is 2 μm to 980 μm; The particle size of the nano starch particles is 50nm~200nm.

5. The preparation method according to any one of claims 1 to 3, characterized in that The method for preparing the nano starch particles comprises the following steps: gelatinizing starch in the presence of a buffer solution with a pH value of 4.5 to 6 to prepare gelatinized starch, treating the gelatinized starch with a debranching enzyme, separating the solid from the liquid, and recrystallizing and drying the obtained supernatant to prepare the nano starch particles; Optionally, the method for preparing the nano starch particles satisfies one or more of the following characteristics: In the step of gelatinizing the starch, the concentration of the starch is 0.05 g / mL to 0.2 g / mL based on the amount of feed; In the step of gelatinizing the starch, the gelatinization is carried out by heating in a boiling water bath for 20 minutes to 60 minutes under stirring; The debranching enzyme comprises one or more of glucoamylase, glycogen debranching enzyme, and starch debranching enzyme; alternatively, the starch debranching enzyme comprises one or more of pullulanase and isoamylase; In the step of treating the gelatinized starch with a debranching enzyme, the gelatinized starch is treated with a debranching enzyme at 40° C. to 60° C. for 5 h to 10 h; After the step of treating the gelatinized starch with a debranching enzyme, the method further comprises heating the reaction product at 90° C. to 100° C. for 30 min to 60 min to inactivate the debranching enzyme; The supernatant is allowed to stand at 0°C to 10°C for 5h to 20h for the recrystallization.

6. The preparation method according to any one of claims 1 to 5, characterized in that Meet one or more of the following characteristics: The inlet air temperature of spray drying is 130℃~160℃; The outlet air temperature of spray drying is less than or equal to 80 ℃; The pressure of spray drying is 0.1Mpa~0.3Mpa; The liquid delivery rate for spray drying is 10 mL / min~13 mL / min; The drying air volume of spray drying is 0.05 m 3 / min~0.1 m 3 / min.

7. A hollow salt microsphere, characterized in that: It is prepared by the preparation method according to any one of claims 1 to 6.

8. The hollow salt microspheres according to claim 7, characterized in that: The particle size of the hollow salt microspheres is 180nm~360nm.

9. The hollow salt microspheres according to claim 7 or 8, characterized in that: Meet one or more of the following characteristics: In the hollow salt microspheres, the mass percentage of C element is 26% to 27%, the mass percentage of O element is 3% to 4%, the mass percentage of Na element is 41% to 42%, and the mass percentage of Cl element is 28% to 29%; The hollow salt microspheres are porous structures.

10. Use of at least one of the hollow salt microspheres prepared by the preparation method according to any one of claims 1 to 6 and the hollow salt microspheres according to any one of claims 7 to 9 in preparing seasonings or foods, wherein the food is a solid food.

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