Process for preparing umami peptide by using hole-sharpening embedding technology

Abstract

The invention discloses a process for preparing umami peptide by using a hole-sharpening embedding technology, which comprises the following steps: S11, preparing a wall material solution: weighing a proper amount of sodium alginate, adding the sodium alginate into a proper amount of distilled water, then fully mixing and dissolving, and standing for 12 hours at a constant temperature of 50-60 DEG C, so that the sodium alginate is thoroughly absorbed and swelled for later use; s12, preparing a mixture of a core material and a wall material: adding the umami peptide and the density-promoting micro-capsule membrane into the wall material solution according to a certain proportion, stirring for 30 minutes, and keeping the temperature at 50 DEG C for later use; s13, preparing a curing liquid: adding CaCl2 into distilled water according to different proportions, and cooling to room temperature for later use; according to the process for preparing the umami peptide by applying the hole-sharpening method embedding technology, the umami peptide prepared by the hole-sharpening method is relatively high in stability, the umami peptide is prevented from being quickly oxidized due to the influence of temperature and an acid environment, the influence on the umami effect is reduced, and a slow-release effect can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of umami peptide preparation, in particular to a process for preparing umami peptide by using sharp hole embedding technology. Background Art

[0002] The embedding technology was developed for the development of pressure-sensitive wall materials for carbonless copy writing paper, and its birth can be traced back to the 1950s. It was then widely used in chemical, casting, medical, pharmaceutical and other industries. In the 1970s, the embedding technology began to be applied to the food field. The early applications were mainly concentrated in food additives, ingredients, health foods, probiotics, etc. In recent years, various embedding processes have continued to emerge, especially the emergence of new wall materials, which has greatly enriched the application of embedding technology.

[0003] At present, encapsulation technology is mainly used to deal with three key issues in the food industry: first, the instability of food ingredients, such as oxidation of proteins, lipids, and active ingredients; fading and discoloration of pigments; and the impact of physical factors on food ingredients. Second, the controlled release of food ingredients, such as the sustained release and delivery of additives, probiotics and other ingredients. Third, the sensory quality of food, such as the adsorption or masking of flavor and odor substances.

[0004] The encapsulation method can change the form of substances, isolate the interactions between substances, reduce volatility, and controllable release. Encapsulation technology was first used in medicines and health products, especially for functional ingredients and probiotics, and then gradually applied to the food field.

[0005] In food processing, wall materials can prevent environmental factors such as oxygen, temperature, humidity, ultraviolet light, etc. from damaging the core material, thereby improving stability and extending shelf life; improving the solubility, hydrophilicity, lipophilicity and other physical properties of the core material; controlling the release conditions and speed of the core material; and shielding the unpleasant taste and odor of the core material to improve product quality. The methods used in food packaging include: spray drying, extrusion, freeze drying, condensation, sharp hole method, adsorption method, etc.

[0006] During food processing, conventional flavor enhancers will be affected by temperature and acidic environment, and the flavor effect will be affected. Therefore, we propose a process for preparing umami peptides using sharp hole embedding technology. Summary of the invention

[0007] The object of the present invention is to provide a process for preparing umami peptides using sharp hole embedding technology to solve the problems raised in the above background technology.

[0008] To achieve the above object, the present invention provides the following technical solution: a process for preparing umami peptides using sharp hole embedding technology, comprising the following steps:

[0009] S11. Preparation of wall material solution: weigh an appropriate amount of sodium alginate, add it to an appropriate amount of distilled water, and then mix it thoroughly. After dissolving, place it at a constant temperature of 50-60°C for 12 hours to allow the sodium alginate to be completely absorbed and expanded before use;

[0010] S12, preparing a mixture of core material and wall material: adding umami peptide and densification-promoting microcapsule membrane to the wall material solution in a certain proportion, stirring for 30 minutes, and keeping warm at 50° C. for standby use;

[0011] S13, preparation of solidifying liquid: adding CaCl2 into distilled water in different proportions and cooling to room temperature for standby use;

[0012] S14, granulation: at a distance of 10 cm from the liquid surface, slowly inject the mixture of the core material and the wall material into the solidifying liquid using an injector to prepare microcapsules;

[0013] S15, curing and drying: stirring and curing at room temperature for 30 minutes to obtain microcapsules, then washing with water to remove CaCl2 on the microcapsules, and then drying in an oven at 40°C to obtain microcapsules.

[0014] Preferably, the process includes selecting the mass ratio of core material to wall material: under the conditions of an operating temperature of 50°C, a CaCl2 mass fraction of 2%, a sucrose fatty acid ester mass fraction of 0.2%, and a sodium alginate mass fraction of 1.5%, different core-to-wall ratios are selected, and the core-to-wall mass ratio is 0.1-0.7.

[0015] Preferably, the process includes selecting the mass fraction of sodium alginate: under the conditions that the mass ratio of core material to wall material is 0.3, the operating temperature is 50°C, the mass fractions of CaCl2 and sucrose fatty acid ester are 2% and 0.2%, the mass fraction of sodium alginate is 0.5%-3.5%.

[0016] Preferably, the process includes the selection of operating temperature: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 1.5%, and CaCl2 and sucrose fatty acid ester mass fractions of 2.0% and 0.2%, the operating temperature is 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, and 60°C.

[0017] Preferably, the process includes selecting the mass fraction of CaCl2: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 1.5%, an operating temperature of 50°C and a sucrose fatty acid ester mass fraction of 0.2%, the mass fraction of CaCl2 is 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, and 3.5%.

[0018] Preferably, the process includes selecting the mass fraction of sucrose fatty acid ester: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 1.5%, an operating temperature of 50°C, and a CaCl2 mass fraction of 2.0%, the sucrose fatty acid ester is 0.1%-0.4%.

[0019] Preferably, Design-Expert 7.0 and Origin 2021 are used to process and plot the test data, and Duncan's new multiple range test is used.

[0020] A method for determining the embedding rate of umami peptides, the method comprising the following steps:

[0021] S21. Preparation of simulated gastric fluid: Prepare according to the Chinese Pharmacopoeia: Take 16.4 mL of dilute hydrochloric acid, add 800 mL of water and 10 g of pepsin, shake, and dilute with water to 1000 mL;

[0022] S22. Drawing of standard curve: Weigh out 600 mg of umami peptide, dissolve in simulated gastric fluid, dilute in a 100 mL volumetric flask, shake evenly, accurately transfer 0-10 mL to a 50 mL volumetric flask, dilute with simulated gastric solution at a wavelength of 280 nm, perform linear regression on absorbance and mass concentration, and obtain the linear regression equation: y=0.039x+0.0308, R2=0.9986;

[0023] S23. Accurately weigh 100 mg of dry microcapsules, crush them, put them into a 100 mL conical flask with a stopper, add 50 mL of 0.5 mol / L sodium citrate solution, shake at 40°C and 50 r / min for 6 hours, centrifuge at 5000 r / min for 10 min, dilute the supernatant to 10 mL, use the obtained supernatant as a control without adding core material, measure the absorbance at 280 nm, determine the mass concentration of the microcapsules by the above linear regression equation, and calculate the embedding rate of the microcapsules according to the following formula:

[0024]

[0025] A method for measuring the content and release of umami peptides is measured by the following formula:

[0026]

[0027] An in vitro release experimental method of a microcapsule preparation in gastric juice comprises the following steps:

[0028] S31, put 200 mg of the dried microcapsules into a 250 mL conical container, then add 200 mL of simulated gastric fluid, react at 60 r / min and 37±1° C., and take 5 mL of sample at regular intervals;

[0029] S32, filtering with a 0.45 μm microporous filter membrane, measuring the absorbance at 280 nm, calculating the concentration of the umami peptide in the simulated gastric fluid by using a standard curve, and calculating the cumulative release in vivo;

[0030] S32, with the unencapsulated goose bone paste fresh peptide as the control group, was compared under the same release conditions.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The preparation process of the umami peptide microcapsules in the present invention is as follows: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 2%, CaCl2 and sucrose fatty acid ester mass fractions of 2.5% and 0.3% respectively, and an operating temperature of 50°C, which is the optimal process for preparing umami peptide microcapsules, and the microcapsule embedding rate is 75.44%.

[0033] In an in vitro simulated digestion experiment of the umami peptide after microcapsulation and the umami peptide not embedded in the present invention, the release amount of the microencapsulated umami peptide is 13.28% after 5 hours, which is basically in a constant release state and the release amount is not high; while the release amount of the umami peptide not embedded reaches 98.68%, and the umami peptide is almost completely released; the release amount of the microcapsule microspheres in the gastric juice is relatively low, and the purpose of sustained release is achieved; the umami peptide after the sharp hole microcapsule is relatively stable, which prevents the umami peptide from being rapidly oxidized by the influence of temperature and acidic environment, reduces the influence on the umami effect, and can achieve the effect of sustained release, etc.; it shows that the sharp hole microcapsule is a more suitable microencapsulation method, and at the same time, the wall material made of sodium alginate has higher solubility in the intestine. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the effect of the ratio of core material to wall material on the embedding rate;

[0035] Figure 2 Schematic diagram of the effect of sodium alginate mass fraction on the embedding rate;

[0036] Figure 3 Schematic diagram of the effect of operating temperature on embedding efficiency;

[0037] Figure 4 Schematic diagram of the effect of CaCl2 content on embedding rate;

[0038] Figure 5 This is a schematic diagram showing the effect of the mass fraction of sucrose fatty acid ester on the embedding efficiency;

[0039] Figure 6 This is a schematic diagram of the standard curve of umami peptide content;

[0040] Figure 7 This is a scanning electron microscope image of the microcapsule (Note: a is magnified 43 times, b is magnified 317 times). DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The present invention provides a technical solution: a process for preparing umami peptides using sharp hole embedding technology, comprising the following steps:

[0043] S11. Preparation of wall material solution: weigh an appropriate amount of sodium alginate, add it to an appropriate amount of distilled water, and then mix it thoroughly. After dissolving, place it at a constant temperature of 50-60°C for 12 hours to allow the sodium alginate to be completely absorbed and expanded before use;

[0044] S12, preparing a mixture of core material and wall material: adding umami peptide and densification-promoting microcapsule membrane to the wall material solution in a certain proportion, stirring for 30 minutes, and keeping warm at 50° C. for standby use;

[0045] S13, preparation of solidifying liquid: adding CaCl2 into distilled water in different proportions and cooling to room temperature for standby use;

[0046] S14, granulation: at a distance of 10 cm from the liquid surface, slowly inject the mixture of the core material and the wall material into the solidifying liquid using an injector to prepare microcapsules;

[0047] S15, curing and drying: stirring and curing at room temperature for 30 minutes to obtain microcapsules, then washing with water to remove CaCl2 on the microcapsules, and then drying in an oven at 40°C to obtain microcapsules.

[0048] As a preferred embodiment, Design-Expert 7.0 and Origin 2021 are used to process and plot the test data, and Duncan's new multiple range test is adopted.

[0049] As a preferred embodiment, the process includes selecting the mass ratio of core material to wall material: under the conditions of an operating temperature of 50°C, a CaCl2 mass fraction of 2%, a sucrose fatty acid ester mass fraction of 0.2%, and a sodium alginate mass fraction of 1.5%, different core-to-wall ratios are selected, and the core-to-wall mass ratio is 0.1-0.7.

[0050] like Figure 1 As shown in the data, when the core-to-wall mass ratio is 0.1-0.3, the embedding rate increases with the increase of the core-to-wall mass ratio; when the core-to-wall ratio exceeds 0.3, the embedding rate decreases. The reason for this is that the embedding performance of three-dimensional calcium alginate is limited; when it reaches its limit, adding more will prevent it from being completely wrapped, thus affecting the embedding efficiency; variance analysis shows that the mass ratio of core material to wall material has a great influence on the embedding effect (P<0.05).

[0051] As a preferred embodiment, the process includes selecting the mass fraction of sodium alginate: under the conditions of a core material to wall material mass ratio of 0.3, an operating temperature of 50°C, and CaCl2 and sucrose fatty acid ester mass fractions of 2% and 0.2%, the mass fraction of sodium alginate is 0.5%-3.5%.

[0052] from Figure 2 It can be seen that when the mass content of sodium alginate is 0.5%-2.0%, the embedding rate of microcapsules shows an increasing trend and reaches the maximum value at 2.0%; at 2.0%-3.5%, the embedding rate decreases instead; the sodium alginate content is low, the reaction with CaCl2 is incomplete, the obtained microcapsule film thickness is small, easy to break, and the embedding rate is low; but after adding a large amount of sodium alginate, the viscosity of its solution increases, which is not conducive to the full fusion and embedding with the flavor enhancer, and reduces the embedding rate. The results show that the amount of sodium alginate has a certain effect on the mechanical strength, ball formation rate and morphology of microcapsules.

[0053] The experiment found that when the sodium alginate content was less than 1.5%, the microspheres collapsed during the drying process; when the mass content of sodium alginate exceeded 2.0%, its permeability became poor, it was difficult to form a ball, and in severe cases, tailing would occur. Variance analysis showed that the mass fraction of sodium alginate had a very significant effect on the embedding rate (P<0.05), so the appropriate mass fraction of sodium alginate was about 2.0%.

[0054] As a preferred embodiment, the process includes the selection of operating temperature: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 1.5%, and a CaCl2 and sucrose fatty acid ester mass fractions of 2.0% and 0.2%, the operating temperature is 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, and 60°C.

[0055] See also Figure 3 At a working temperature of 50°C, the embedding rate of microcapsules is the highest. This is because the viscosity of sodium alginate is high at low temperatures, which is not conducive to sharp hole granulation; when the temperature is increased, the entanglement between the molecular segments of sodium alginate will stretch, making it easier to bind with Ca 2+ Bonding to form a network structure. When the temperature is too high, the molecular structure of sodium alginate is easily dispersed, and it is difficult to form a network structure with calcium ions, resulting in a decrease in gel performance.

[0056] The results of variance analysis showed that the reaction temperature had a significant effect on the entrapment rate of umami peptides (P<0.05). Since high temperature can easily lead to the inactivation of umami peptides, the optimal process condition of 50°C was adopted in this process.

[0057] As a preferred embodiment, the process includes selecting the mass fraction of CaCl2: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 1.5%, an operating temperature of 50°C and a sucrose fatty acid ester mass fraction of 0.2%, the mass fraction of CaCl2 is 0.5%, 1%, 1.5%, 2%, 2.5%, 3% and 3.5%.

[0058] Depend on Figure 4 It can be seen that when the mass content of CaCl2 is 0.5%-2.5%, the embedding rate of the microcapsules increases with the passage of time; when the concentration is 2.5%-3.5%, the embedding rate decreases instead.

[0059] Due to the low CaCl2 content in the gel solution, the cross-linking degree between sodium alginate and calcium ions is reduced. Therefore, the epidermis of calcium alginate microspheres becomes thinner and the strength decreases, thereby affecting the embedding rate of alginate microspheres. However, when the CaCl2 content is too high, the surface layer solidifies quickly, and a dense epidermis will appear before the inner layer solidifies, preventing the coagulant from further diffusing into the inner layer, causing the inner layer to harden completely, which is not conducive to enhancing the strength of the microspheres.

[0060] Calcium chloride also has a certain effect on the morphology and color of microcapsules. The experimental results show that when the CaCl2 content is lower than 2.5%, the generation rate of calcium alginate microspheres is slow and there is a large agglomeration phenomenon; in products above 2.5%, the product color becomes darker and has an astringent taste; variance analysis shows that when the CaCl2 content is different, the encapsulation rate has a very obvious difference (P<0.05).

[0061] As a preferred embodiment, the process includes selecting the mass fraction of sucrose fatty acid ester: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 1.5%, an operating temperature of 50°C, and a CaCl2 mass fraction of 2.0%, the sucrose fatty acid ester is 0.1%-0.4%.

[0062] Depend on Figure 5 It shows that when the mass content of sucrose fatty acid ester is 0.3%, the embedding rate of microcapsules is the highest, and then begins to decrease. The reason is that when its mass content is very small, it can interact with sodium alginate through van der Waals force, hydrophobic bond, electrostatic force, and hydrogen bond, and can form a composite structure in the sodium alginate network structure. The prepared microcapsule structure is tighter and the embedding effect is better. When excessive sucrose fatty acid ester enters the sodium alginate chain, it will increase the gap between the sodium alginate chains and reduce the force between the chains, thereby weakening the strength of the prepared microcapsules and reducing the embedding rate.

[0063] The variance analysis showed that the effect of sucrose fatty acid content on the embedding rate was very significant (P<0.05), and the sucrose fatty acid ester content was measured to be 0.3%.

[0064] Determination of the embedding rate of microcapsule products:

[0065] The determination method comprises the following steps:

[0066] S21. Preparation of simulated gastric fluid: Prepare according to the Chinese Pharmacopoeia: Take 16.4 mL of dilute hydrochloric acid (corresponding to 3.84 mL of concentrated hydrochloric acid), add 800 mL of water and 10 g of pepsin, shake, and dilute to 1000 mL with water;

[0067] S22. Drawing of standard curve: Weigh out 600 mg of umami peptide, dissolve it in simulated gastric fluid, dilute it in a 100 mL volumetric flask, shake it evenly, accurately transfer 0-10 mL to a 50 mL volumetric flask, dilute it with simulated gastric solution at a wavelength of 280 nm, perform linear regression between absorbance and mass concentration, and obtain the standard curve. Figure 6 It can be seen that the linear regression equation is y = 0.039x + 0.0308, R2 = 0.9986, indicating that the concentration of umami peptides has a good linear relationship with absorbance, so the absorbance can be used to determine the concentration of umami peptides;

[0068] S23. Accurately weigh 100 mg of dry microcapsules, crush them, put them into a 100 mL conical flask with a stopper, add 50 mL of 0.5 mol / L sodium citrate solution, shake at 40°C and 50 r / min for 6 hours, centrifuge at 5000 r / min for 10 min, dilute the supernatant to 10 mL, use the obtained supernatant as a control without adding core material, measure the absorbance at 280 nm, determine the mass concentration of the microcapsules by the above linear regression equation, and calculate the embedding rate of the microcapsules according to the following formula:

[0069]

[0070] Comparison of moisture content and fluidity of microcapsule products:

[0071] The method for measuring the water content is: first weigh the constant weight of the bottle in an oven at 105°C: place a clean weighing bottle in an oven at 105°C for several hours (usually two hours or more), then remove it, keep it in the oven for 30 minutes and weigh it accurately. Place it in the oven and dry it at 105°C for one hour, then remove it, keep it in a drying dish at room temperature for 30 minutes, and weigh it accurately until the difference in weight after two consecutive dryings is less than 0.3mg; then weigh the test object, crush the test object into particles or fragments with a diameter of no more than 3mm, 2-5g (or the weight listed in this category) is spread on a flat weighing device that is dried to constant weight, its height is no more than 5mm, and the loose sample is no more than 10mm, and weigh it accurately; finally dry weigh: if there is no special instruction, place the weighing bottle with the test object in an oven heated to 105°C, and remove the lid and place it next to the weighing bottle.

[0072] The method for determining the fluidity of microcapsule products is: There are many ways to determine the angle of repose. The most common way to determine the angle of repose is: when the particle passes through the "funnel", its height is related to the frame, or its height can change with the shape of the cone; the fluidity of the particle is determined by measuring the angle of repose.

[0073] Moisture content is an important indicator for measuring the shelf life of products. If the humidity is too high, the product is easy to clump, moldy, and difficult to preserve. The fluidity will have a certain impact on subsequent processing such as transportation, screening, drying, etc. It is very necessary to detect the fluidity of microcapsules. The fluidity of powders cannot usually be characterized by a single characteristic parameter, but can also be described by the angle of repose. The smaller the angle of repose, the smaller the friction will be, and the better the flow performance. Usually, when θ≤30°, the fluidity is good, when 30°≤θ≤45°, the fluidity is good, when 45°≤θ≤60°, the fluidity is general, and when θ≥60°, the fluidity is poor. The moisture content and flow performance of the microcapsule products measured in this experiment are shown in Table 1.

[0074] Table 1 Moisture content and fluidity of microcapsules

[0075] Moisture content / % Angle of repose / ° Microcapsules 2.98±0.21 43.6±0.36

[0076] As shown in Table 1, the water content of the microcapsules is 2.98±0.21%, which is an extremely low water content and is suitable for long-term storage. Under this condition, the repose angle of the microcapsules is 43.6°±0.36°, which has good rheological properties. Due to the large size of the microcapsules and the weak adhesion between the particles, the repose angle is small and the flow performance is better. In addition, attention should be paid to whether its surface is smooth, the charge on the particles, the hygroscopicity of the wall material used, and other factors that will have a negative impact on the fluidity of the microcapsules.

[0077] Observation of the morphology of microencapsulated products:

[0078] The prepared microcapsules were placed in an oven for drying at 105°C, conductive glue was adhered to the sample stage, and then gold was sprayed, and the surface structure was analyzed by SEM.

[0079] The influence of the surface state of microcapsules on a series of properties is most significant on the sustained release and controlled release of the core material. It has a great influence on the fluidity of microcapsules and the pore structure of particles. The structure is usually observed using a scanning electron microscope or an optical microscope, such as Figure 7 The surface structure of the microcapsules observed by SEM, using sodium alginate as the wall material and calcium chloride as the coagulant, the shape of the prepared umami peptide microcapsules is spherical; the microspheres are uniform in size, without deformation, complete in structure, without cracks on the surface, and have good integrity and density; the results show that the microcapsules prepared by the sharp hole method have a better protective effect on the core material.

[0080] In vitro release experiment of microcapsule preparation in gastric juice:

[0081] The impact of environmental factors in the human body on microencapsulated food has many changes, and the amount of release is an important indicator for evaluating its changes in the body. Especially when the core material is easily decomposed by gastric acid and pepsin, sudden release is more likely to occur. Therefore, the release amount is the most important indicator for evaluating the quality of microcapsules. The umami peptide content and release amount are determined by the following formula:

[0082]

[0083] The experimental method includes the following steps:

[0084] S31, put 200 mg of the dried microcapsules into a 250 mL conical container, then add 200 mL of simulated gastric fluid, react at 60 r / min and 37±1° C., and take 5 mL of sample at regular intervals;

[0085] S32, filtering with a 0.45 μm microporous filter membrane, measuring the absorbance at 280 nm, calculating the concentration of the umami peptide in the simulated gastric fluid by using a standard curve, and calculating the cumulative release in vivo;

[0086] S32, with the unencapsulated goose bone paste fresh peptide as the control group, was compared under the same release conditions.

[0087] As shown in Table 2, after the unencapsulated umami peptide was dissolved in gastric juice for 5 hours, its release amount was as high as 98.68%, which was basically completely released. The unencapsulated umami peptide was rapidly released because it was not resistant to decomposition by gastric acid and pepsin. The release amount of umami peptide after microencapsulation was 13.28%, and it was released at a constant rate. The release amount was not large. This was because the wall material of the microcapsule, alginate microspheres, had pH-sensitive properties and were not easy to swell in an acidic environment, but could swell under alkaline conditions, thereby hindering the release of the core material.

[0088] Table 2 Release amount of umami peptide microcapsules in simulated gastric fluid

[0089]

[0090] The results showed that the optimal process for preparing umami peptide microcapsules was when the mass ratio of core material to wall material was 0.3, the mass fraction of sodium alginate was 2%, the mass fractions of CaCl2 and sucrose fatty acid ester were 2.5% and 0.3% respectively, and the operating temperature was 50°C, and the microcapsule encapsulation efficiency was 75.44%.

[0091] In the in vitro simulated digestion experiment of the umami peptides after microencapsulation and the unencapsulated umami peptides, the release of the microencapsulated umami peptides was 13.28% after 5 hours, which was basically in a constant rate release state and the release amount was not high; while the release amount of the unencapsulated umami peptides reached 98.68%, and the umami peptides were almost completely released; the release amount of the microcapsule microspheres in the gastric juice was low, achieving the purpose of sustained release; the umami peptides after sharp-hole microencapsulation were more stable, preventing the umami peptides from being quickly oxidized by the temperature and acidic environment, reducing the impact on the umami effect, and achieving the effect of sustained release, etc.; it shows that the sharp-hole microencapsulation method is a more suitable microencapsulation method, and at the same time, the wall material made of sodium alginate has a higher solubility in the intestine.

[0092] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0093] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for preparing umami peptides using sharp hole embedding technology, characterized in that: The following steps are involved: S11. Preparation of wall material solution: weigh an appropriate amount of sodium alginate, add it to an appropriate amount of distilled water, and then mix it thoroughly. After dissolving, place it at a constant temperature of 50-60°C for 12 hours to allow the sodium alginate to be completely absorbed and expanded before use; S12, preparing a mixture of core material and wall material: adding umami peptide and densification-promoting microcapsule membrane to the wall material solution in a certain proportion, stirring for 30 minutes, and keeping warm at 50° C. for standby use; S13, preparation of solidifying liquid: adding CaCl2 into distilled water in different proportions and cooling to room temperature for standby use; S14, granulation: at a distance of 10 cm from the liquid surface, slowly inject the mixture of the core material and the wall material into the solidifying liquid using an injector to prepare microcapsules; S15, curing and drying: stirring and curing at room temperature for 30 minutes to obtain microcapsules, then washing with water to remove CaCl2 on the microcapsules, and then drying in an oven at 40°C to obtain microcapsules.

2. The process for preparing umami peptides using sharp hole embedding technology according to claim 1, characterized in that: The process includes selecting the mass ratio of core material to wall material: under the conditions of operating temperature of 50°C, CaCl2 mass fraction of 2%, sucrose fatty acid ester mass fraction of 0.2%, and sodium alginate mass fraction of 1.5%, different core-to-wall ratios are selected, and the core-to-wall mass ratio is 0.1-0.

7.

3. The process for preparing umami peptides by using sharp hole embedding technology according to claim 1, characterized in that: The process includes the selection of the mass fraction of sodium alginate: under the conditions that the mass ratio of core material to wall material is 0.3, the operating temperature is 50°C, the mass fractions of CaCl2 and sucrose fatty acid ester are 2% and 0.2%, the mass fraction of sodium alginate is 0.5%-3.5%.

4. The process for preparing umami peptides by using sharp hole embedding technology according to claim 1, characterized in that: The process includes the selection of operating temperature: under the conditions that the mass ratio of core material to wall material is 0.3, the mass fraction of sodium alginate is 1.5%, and the mass fractions of CaCl2 and sucrose fatty acid ester are 2.0% and 0.2%, the operating temperature is 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, and 60°C.

5. The process for preparing umami peptides by using sharp hole embedding technology according to claim 1, characterized in that: The process includes the selection of the mass fraction of CaCl2: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 1.5%, an operating temperature of 50°C and a sucrose fatty acid ester mass fraction of 0.2%, the mass fraction of CaCl2 is 0.5%, 1%, 1.5%, 2%, 2.5%, 3% and 3.5%.

6. The process for preparing umami peptides by using sharp hole embedding technology according to claim 1, characterized in that: The process includes the selection of the mass fraction of sucrose fatty acid ester: under the conditions of a core material to wall material mass ratio of 0.3, a sodium alginate mass fraction of 1.5%, an operating temperature of 50°C, and a CaCl2 mass fraction of 2.0%, the sucrose fatty acid ester is 0.1%-0.4%.

7. The process for preparing umami peptides by using sharp hole embedding technology according to claim 1, characterized in that: Design-Expert 7.0 and Origin 2021 were used to process and plot the test data, and Duncan’s new multiple range test was used.

8. A method for determining the embedding rate of umami peptides, characterized in that: The method comprises the following steps: S21. Preparation of simulated gastric fluid: Prepare according to the Chinese Pharmacopoeia: Take 16.4 mL of dilute hydrochloric acid, add 800 mL of water and 10 g of pepsin, shake, and dilute with water to 1000 mL; S22. Drawing of standard curve: Weigh out 600 mg of umami peptide, dissolve in simulated gastric fluid, dilute in a 100 mL volumetric flask, shake evenly, accurately transfer 0-10 mL to a 50 mL volumetric flask, dilute with simulated gastric solution at a wavelength of 280 nm, perform linear regression on absorbance and mass concentration, and obtain the linear regression equation: y=0.039x+0.0308, R2=0.9986; S23. Accurately weigh 100 mg of dry microcapsules, crush them, put them into a 100 mL conical flask with a stopper, add 50 mL of 0.5 mol / L sodium citrate solution, shake at 40°C and 50 r / min for 6 hours, centrifuge at 5000 r / min for 10 min, dilute the supernatant to 10 mL, use the obtained supernatant as a control without adding core material, measure the absorbance at 280 nm, determine the mass concentration of the microcapsules by the above linear regression equation, and calculate the embedding rate of the microcapsules according to the following formula:

9. A method for determining the content and release of umami peptides, characterized in that: This method determines the content and release of umami peptides using the following formula:

10. An in vitro release test method of a microcapsule preparation in gastric juice, characterized in that: The experimental method includes the following steps: S31, put 200 mg of the dried microcapsules into a 250 mL conical container, then add 200 mL of simulated gastric fluid, react at 60 r / min and 37±1° C., and take 5 mL of sample at regular intervals; S32, filtering with a 0.45 μm microporous filter membrane, measuring the absorbance at 280 nm, calculating the concentration of the umami peptide in the simulated gastric fluid by using a standard curve, and calculating the cumulative release in vivo; S32, with the unencapsulated goose bone paste fresh peptide as the control group, was compared under the same release conditions.

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