Multifunctional powdered oil rich in diglyceride, and large-scale preparation method and application thereof

Abstract

The invention belongs to the field of food processing, food nutrition and special medical food, and relates to an embedding technology of composite resistant starch and multi-structure functional lipid, in particular to multifunctional powdered oil and fat and a large-scale preparation method of the multifunctional powdered oil and fat. A series of powdered oil products based on OSA starch (wall material)-diglyceride (core material) are constructed through non-covalent interaction, crystal structure diffraction characteristic peaks exist at 12.8 degrees and 19.8 degrees in an X-ray diffraction pattern, and the structure is stable. The preparation method is simple and easy to operate, green in process and free of any small molecule additive. The food has a good antioxidant protection effect, high oxidation resistance, high digestion resistance and high emulsifying activity, has multiple nutritional and healthy characteristics, and can be used in the fields of special medical foods, functional foods, nutritional additives and the like.

Description

Technical Field

[0001] The present invention belongs to the fields of food processing, food nutrition and special medical foods, and relates to the encapsulation technology of composite resistant starch and multi-structure functional lipids. Specifically, the present invention relates to a multifunctional powdered oil rich in diglyceride with high antioxidant properties, high enzyme resistance and high emulsification activity, as well as a large-scale preparation method thereof, and its application in special medical foods, functional foods and nutritional additives. Background Art

[0002] Long-term excessive intake of fats and oils increases the risk of chronic diseases such as obesity, hypertension, hyperlipidemia, and diabetes, causing varying degrees of harm to human health. A balanced diet not only provides energy but also boosts immune function and maintains neural and physiological activity. Therefore, while controlling dietary fat intake, it is particularly important to enhance the health properties of fats and oils.

[0003] Diacylglycerol (DAG), a key intermediate in oil metabolism, is safe, nutritious, and healthy. Depending on the position of the fatty acid acyl group attached to the hydroxyl group on the glycerol backbone, diacylglycerol can be divided into two different configurations: 1,2- and 1,3-diacylglycerol. In recent years, increasing dietary diacylglycerol intake has been shown to reduce visceral fat, lower blood lipids, improve cardiovascular health, alleviate diabetes and its complications, and prevent obesity, among other nutritional and health benefits. However, as a functional oil, diacylglycerol presents various disadvantages in actual food processing and application. These include susceptibility to oxidation under environmental factors such as light, heat, and oxygen; poor distribution uniformity; and immiscibility between oil and water, which limits its application in the food industry. Common diacylglycerols include dilaurin, dimyristin, dipalmitin, and distearin.

[0004] Powdered oil is a common food ingredient, mainly composed of raw materials such as lipids, carbohydrates, and proteins. It is widely used in the processing of various foods such as coffee, oatmeal, condiments, and baked goods. The powdered oil obtained by microencapsulation has an internal core material (oil) that is not easily affected by the environment because it is protected. The oxidative stability of the product is improved, the storage period is extended, the special flavor of odorous substances is masked, and it is easy to circulate and store. It overcomes the limitations of the original oil in the application process and expands its scope of use. Despite this, the common powdered oils prepared by the current public technology still have many problems such as complicated and cumbersome processes, single functions and nutritional qualities, the use of a large number of artificially synthesized additives such as antioxidants and emulsifiers, complex ingredients and poor product stability. These will bring hidden dangers to it in the processing of various foods, increase food safety risks, and make it difficult to meet consumers' demand for healthy and high-quality food.

[0005] Therefore, it is urgent to develop a powdered oil preparation technology that has simple preparation steps, is easy to operate, is green and additive-free, rich in functional oils and meets diversified nutritional needs. This will help promote the diversification and high-end development of food products in related fields, and has important theoretical significance and application value for improving food quality and nutritional health.

[0006] POV: Peroxide value, peroxide value of diglyceride.

[0007] TBARS: Thiobarbituric acid reactive substances.

[0008] OSA starch: Octenyl Succiniate anhydrate starch, octenyl succinate starch ester.

[0009] Functional oils: edible oils that contain nutrients that can regulate human health. Summary of the Invention

[0010] In view of this, the present invention aims to overcome the defects in the prior art and develop a powdered oil preparation technology that has simple preparation steps, is easy to operate, is green and additive-free, rich in functional oils and meets diversified nutritional needs, and constructs a multifunctional powdered oil rich in diglycerides.

[0011] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0012] The method of the present invention is the first to construct a multifunctional powdered oil rich in diglyceride by utilizing modified starch and lipid through non-covalent bond interaction.

[0013] The multifunctional powdered oil of the present invention has characteristic diffraction peaks of crystal structure at 12.8° and 19.8° in its X-ray diffraction spectrum.

[0014] The multifunctional powdered oil of the present invention has a relative crystallinity of 22.3-25.7%, a short-range molecular order determined by infrared spectroscopy of 0.68-0.71, and a short-range molecular order determined by Raman spectroscopy of 15.21-15.56. The oil has a rod-like morphology of a certain size with a width of about 13.57-17.86 μm and a length of about 31.43-42.14 μm.

[0015] The multifunctional powdered oil of the present invention has strong enzyme resistance of 55.8-57.1%, and has strong antioxidant protection effect on functional oils (POV range is 3.91-4.12 mmol / kg, TBARS range is 3.05-3.15 μmol / kg).

[0016] The multifunctional powdered oil of the present invention comprises OSA starch as the modified starch and functional oil as the lipid.

[0017] Furthermore, in the multifunctional powdered oil, the OSA starch is selected from corn starch with A-type crystal structure, potato starch with B-type crystal structure, and pea starch with C-type crystal structure, and is obtained through an OSA esterification modification reaction.

[0018] Furthermore, in the multifunctional powdered oil, the degree of substitution of OSA starch is 0.0147-0.0486.

[0019] Furthermore, in the multifunctional powdered oil, the functional oil is selected from functional glycerides and polyunsaturated fatty acids; further, functional diglycerides are preferred among the functional glycerides; preferably, the diglycerides are any one or more of 1,2 configuration or 1,3 configuration.

[0020] The diglyceride can be selected from: 1,2-configuration diglyceride is 1,2-configuration dilaurin, 1,2-configuration dimyristin, 1,2-configuration dipalmitin, 1,2-configuration distearin; 1,3-configuration dilaurin, 1,3-configuration dimyristin, 1,3-configuration dipalmitin, 1,3-configuration distearin.

[0021] The multifunctional powdered oil rich in diglyceride of the present invention can be prepared by the following method:

[0022] (1) OSA modification of natural starch to obtain OSA starch;

[0023] (2) preparing an OSA starch suspension, adding diglyceride, and heating;

[0024] (3) Cooling under controlled temperature, centrifugation with ethanol precipitation, and drying.

[0025] Furthermore, the present invention can prepare the multifunctional powdered oil rich in diglyceride by:

[0026] (1) Disperse natural starch in deionized water solution, add OSA modification reagent after heating, adjust pH value, control OSA modification reagent to be added dropwise within a certain period of time, continue to stir and modify, and then centrifuge to obtain precipitate, i.e. OSA starch.

[0027] (2) Add diglyceride to the OSA starch suspension, continue magnetic stirring, heat to 90°C and stir thoroughly to obtain a powdered oil sample solution.

[0028] (3) The powdered oil sample solution was stirred and cooled to 20°C. The cooled powdered oil sample solution was then precipitated with anhydrous ethanol at a ratio of 1:4 (v / v) for 15 h. The precipitate was centrifuged at 3000 g for 8 min. The precipitate was dried for 12 h and ground through a 100-mesh sieve to obtain the powdered oil.

[0029] The method for preparing the multifunctional powdered oil rich in diglyceride of the present invention can be:

[0030] In step (1), the natural starch is corn starch, the amount of OSA modification reagent added is 3-9% based on the dry weight of the starch, the reagent addition time is continuous for 1-1.5 hours, and the reaction is continued for 2-3 hours, during which the pH value is regulated at 7.5-8.0 and the stirring rate is 900-1200 rpm.

[0031] In step (2), the concentration of the starch suspension is 5-10% (wt%), the diglyceride is 5-8% (w / w) based on the dry basis of the starch, the stirring speed is 600-800 rpm, the duration is 7-9 minutes, and the heating reaction is continued for 1.5-2.5 hours, during which the speed is 500-800 rpm.

[0032] In the step (3), the powdered oil sample solution is cooled to 70° C. within 3-4 hours at a cooling rate of 0.3-0.4° C. / min, and the stirring rate during the cooling period is 100-200 rpm.

[0033] The products described in the present invention include special medical foods and functional foods.

[0034] Compared with the traditional method, the present invention has the following advantages and effects, including but not limited to:

[0035] (1) Stable product structure;

[0036] (2) High antioxidant properties;

[0037] (3) Stronger enzyme resistance and lower enzyme digestibility;

[0038] (4) High emulsifying activity;

[0039] (5) rich in diacylglycerol (23.66-29.05 mg of diacylglycerol per gram of sample);

[0040] (6) No need for any small molecule additives, green process;

[0041] (7) The preparation method is simple and easy to operate;

[0042] (8) It has multiple nutritional and health properties.

[0043] The present invention provides a method for preparing powdered oils and fats with simple preparation steps, easy operation, green and additive-free, rich in functional oils and fats, and meeting diversified nutritional needs. The method utilizes OSA chemical esterification to modify starch, and reacts it with functional oils and fats through non-covalent bond interactions. After a continuous heating stage and a temperature-controlled cooling stage, a series of multifunctional powdered oils and fats based on OSA starch (wall material) and diglyceride (core material) are constructed. Compared with powdered oils and fats prepared by traditional methods, the powdered oils and fats prepared by the present invention are rich in diglyceride, have a V-type crystal structure, and are highly stable. The X-ray diffraction pattern has characteristic peaks of a V-type crystal structure at 12.8° and 19.8°, and the structure is stable.

[0044] Compared with traditional preparation methods, the preparation method of the present invention is simple and easy to operate, and the green process does not require any small molecule additives. It is low-cost, green and sustainable, easy to operate, does not require the addition of additional reagents or excipients, is environmentally friendly, safe, and non-toxic to organisms.

[0045] The multifunctional powdered oil of the present invention has good antioxidant protection for oils and fats, high antioxidant activity, high digestibility, high emulsification activity, and multiple nutritional and health properties, and can be used in the fields of special medical foods, functional foods, nutritional additives, etc.

[0046] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 The molecular model diagrams of dipalmitin with different configurations;

[0048] Figure 2 The 1H NMR spectra of the embodiments and comparative examples are shown in FIG.

[0049] Figure 3 The X-ray diffraction patterns of the embodiments and comparative examples are shown in FIG.

[0050] Figure 4 The following are Fourier transform infrared spectra of the embodiments and comparative examples;

[0051] Figure 5 The differential scanning calorimeter diagrams of the embodiments and comparative examples;

[0052] Figure 6 The morphology and structure diagrams of the embodiments and comparative examples are shown;

[0053] Figure 7 is the intermolecular interaction force of the embodiment;

[0054] Figure 8 It is the digestion curve diagram of Example and Comparative Example;

[0055] Figure 9 1 is a graph showing the change in POV levels of oils and fats in Examples and Comparative Examples over storage time;

[0056] Figure 10 Graph showing changes in TBARS levels of oils and fats in Examples and Comparative Examples over storage time. DETAILED DESCRIPTION

[0057] The following will describe in more detail exemplary optimized embodiments disclosed in the present invention to further illustrate the present invention. Although the specification shows exemplary optimized embodiments disclosed in the present invention, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art, so as to help those skilled in the art have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention.

[0058] Example 1 Preparation of OSA starch (from corn starch)

[0059] The OSA starch used in the following examples can be prepared by the following method:

[0060] 10g (dry weight) of native corn starch was accurately weighed to prepare a 20% starch suspension (wt%). A 3% OSA modifier (based on the starch dry weight) was added dropwise over 1.5 hours. The pH was adjusted between 7.9 and 8.0. The reaction was continued at 40°C for 3 hours with a stirring rate of 1200 rpm. The OSA starch solution was centrifuged at 3000g for 8 minutes, followed by three cycles of washing with deionized water and anhydrous ethanol. The resulting sample was dried for 12 hours and ground through a 100-mesh sieve to obtain OSA starch (OSAMS).

[0061] Preparation of Example 2OSA starch (sourced from potato starch)

[0062] The OSA starch used in the following examples can be prepared by the following method:

[0063] 10g (dry weight) of native potato starch was accurately weighed to prepare a 20% starch suspension (wt%). A 3% OSA modifier (based on the starch dry weight) was added dropwise over 1.5 hours. The pH was adjusted between 7.9 and 8.0. The reaction was continued at 40°C for 3 hours with a stirring rate of 1200 rpm. The OSA starch solution was centrifuged at 3000g for 8 minutes, followed by three cycles of washing with deionized water and anhydrous ethanol. The resulting sample was dried for 12 hours and ground through a 100-mesh sieve to obtain OSA starch (OSAMS).

[0064] Example 3 Preparation of OSA starch (pea starch source)

[0065] The OSA starch used in the following examples can be prepared by the following method:

[0066] 10 g (dry weight) of native pea starch was accurately weighed to prepare a 20% starch suspension (wt%). A 3% OSA modifier (based on the starch dry weight) was added dropwise over 1.5 hours. The pH was adjusted between 7.9 and 8.0. The reaction was continued at 40°C for 3 hours with a stirring rate of 1200 rpm. The OSA starch solution was centrifuged at 3000 g for 8 minutes, followed by three cycles of washing with deionized water and anhydrous ethanol. The resulting sample was dried for 12 hours and ground through a 100-mesh sieve to obtain OSA starch (OSAMS).

[0067] Example 4 Preparation of Powdered Grease (OSAMS-1,2DPG)

[0068] OSA starch (degree of substitution 0.0191) was prepared into an 8% starch suspension (wt%), and 6% (w / w) 1,2-dipalmitoylglycerol (1,2DPG; see Figure 1 ), stirring at 800 rpm for 8 min, and heating at 90° C. for 2.5 h at a stirring speed of 700 rpm.

[0069] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain the powdered oil (OSAMS-1,2DPG).

[0070] Example 5 Preparation of Powdered Grease (OSAMS-1,3DPG)

[0071] OSA starch (degree of substitution 0.0191) was prepared into an 8% starch suspension (wt%), and 6% (w / w) of 1,3-dipalmitoylglycerol (1,3DPG; see Figure 1 ), stirring at 800 rpm for 8 min, and heating at 90° C. for 2.5 h at a stirring speed of 700 rpm.

[0072] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain the powdered oil (OSAMS-1,3DPG).

[0073] Comparative Example 1 Preparation of Comparative Powdered Grease (NMS-1,2DPG)

[0074] The native corn starch (substitution degree is 0) is prepared into 8% starch suspension (wt%), and 6% (w / w) 1,2-configuration dipalmitoylglycerol (see Figure 1 ), stirring at 800 rpm for 8 min, and heating at 90° C. for 2.5 h at a stirring speed of 700 rpm.

[0075] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain powdered oil (NMS-1,2DPG).

[0076] Comparative Example 2 Preparation of Comparative Powdered Grease (NMS-1,3DPG)

[0077] The native starch (substitution degree is 0) is prepared into 8% starch suspension (wt%), and 6% (w / w) 1,3-dipalmitoylglycerol (see Figure 1 ), stirring at 800 rpm for 8 min, and heating at 90° C. for 2.5 h at a stirring speed of 700 rpm.

[0078] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain powdered oil (NMS-1,3DPG).

[0079] Comparative Example 3 Preparation of Comparative Grease (1,2DPG)

[0080] The 1,2-configured dipalmitoylglycerol (1,2DPG) was placed in the same water bath conditions as in Example 4 and treated using the same operating steps to obtain the 1,2DPG comparison oil.

[0081] Comparative Example 4 Preparation of Comparative Grease (1,3DPG)

[0082] The 1,3-configured dipalmitoylglycerol (1,3DPG) was placed in the same water bath conditions as in Example 5 and treated using the same operating steps to obtain the 1,3DPG comparison oil.

[0083] Comparative Example 5: Natural corn starch

[0084] Natural corn starch that has not been processed in any way.

[0085] Comparative Example 6: A new preparation method designed by the applicant and subsequently eliminated

[0086] Conventional corn starch was prepared with the prepared ionic liquid complex to form a 10wt% starch emulsion; the pH value of the system was then adjusted to 8.0-8.5; 3% of the dry weight of the starch was weighed as octenylsuccinic anhydride, and the reaction was continued at 25°C for 5 hours (the modification reagent was added within 2.5 hours) with a stirring rate of 200 rpm; after the reaction, the pH value of the system was adjusted to 6.0; the mixture was washed three times with deionized water and 70% ethanol by alternating centrifugation (5000g, 10min); the precipitate after centrifugation was placed in a vacuum drying oven at 40°C and dried for 12 hours.

[0087] The dried sample was prepared into an 8wt% octenylsuccinate starch suspension. Dipalmitoylglycerol (1,2 configuration) was then added to the suspension (at a 1:20 weight ratio to the modified starch dry basis) and stirred at 260 rpm for 2 minutes. Finally, a binary complex of octenylsuccinate-modified starch and palmitic acid was obtained through preheating, mixing, heating, and cooling. Specifically, the modified starch-lipid suspension was preheated and stirred at 50°C for 2 minutes at a stirring rate of 200 rpm; the temperature was increased to 100°C at a heating rate of 25°C / min, the composite reaction time was 1 hour, and the stirring rate was 260 rpm; the temperature was then cooled to 25°C at a cooling rate of 10°C / min and the stirring rate was 100 rpm; the obtained paste sample was placed in liquid nitrogen and cooled for 5 minutes, freeze-dried for 24 hours, and then ground using a high-throughput liquid nitrogen cryo-grinder at a rotation speed of 10 cps for 10 minutes and passed through a 100-mesh sieve.

[0088] Example 6 Preparation of Powdered Grease (OSAMS-1,2DPG)

[0089] OSA starch (degree of substitution 0.0147) was prepared into a 5% starch suspension (wt%). 1,2-dipalmitoylglycerol was added at 5% (w / w) based on the dry starch basis. The mixture was stirred at 600 rpm for 7 minutes and heated at 90°C for 1.5 hours at 600 rpm. The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm during the cooling period.

[0090] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain the powdered oil (OSAMS-1,2DPG).

[0091] Example 7 Preparation of Powdered Grease (OSAMS-1,2DPG)

[0092] OSA starch (degree of substitution 0.0147) was prepared into a 10% starch suspension (wt%). 8% (w / w) 1,2-dipalmitoylglycerol, based on the dry starch basis, was added. The mixture was stirred at 800 rpm for 9 minutes and heated at 90°C for 2.5 hours at 800 rpm. The sample solution was then cooled to 20°C at a cooling rate of 0.4°C / min over 3 hours, with a stirring rate of 200 rpm during the cooling period.

[0093] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain the powdered oil (OSAMS-1,2DPG).

[0094] Example 8 Preparation of Powdered Grease (OSAMS-1,3DPG)

[0095] OSA starch (degree of substitution 0.0486) was prepared into a 5% starch suspension (wt%). 1,3-dipalmitoylglycerol was added at 5% (w / w) based on the dry starch basis. The mixture was stirred at 600 rpm for 7 minutes and heated at 90°C for 1.5 hours at 600 rpm. The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm during the cooling period.

[0096] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain the powdered oil (OSAMS-1,3DPG).

[0097] Example 9 Preparation of Powdered Grease (OSAMS-1,3DPG)

[0098] OSA starch (degree of substitution 0.0486) was prepared into a 10% starch suspension (wt%). 8% (w / w) 1,3-dipalmitoylglycerol, based on the dry starch basis, was added. The mixture was stirred at 800 rpm for 9 minutes and heated at 90°C for 2.5 hours at 800 rpm. The sample solution was then cooled to 20°C at a cooling rate of 0.4°C / min over 3 hours, with a stirring rate of 200 rpm during the cooling period.

[0099] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain the powdered oil (OSAMS-1,3DPG).

[0100] Example 10 Preparation of powdered oil (OSAMS-1,2DLG)

[0101] OSA starch (degree of substitution 0.0147) was prepared into a 5% starch suspension (wt%), and 5% (w / w) 1,2-dilaurin (1,2DLG) based on the dry starch was added. The mixture was stirred at 600 rpm for 7 minutes and heated at 90°C for 1.5 hours at 600 rpm. Subsequently, the sample solution was cooled to 20°C at a cooling rate of 0.3°C / min over 4 hours, with a stirring rate of 100 rpm during the cooling period.

[0102] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain powdered oil (OSAMS-1,2DLG).

[0103] Example 11 Preparation of powdered oil (OSAMS-1,3DLG)

[0104] OSA starch (degree of substitution 0.0147) was prepared into a 5% starch suspension (wt%), and 5% (w / w) 1,3-dilaurin (1,3DLG) based on the dry starch was added. The mixture was stirred at 600 rpm for 7 minutes and heated at 90°C for 1.5 hours at 600 rpm. The sample solution was then cooled to 20°C at a cooling rate of 0.3°C / min over 4 hours, with a stirring rate of 100 rpm during the cooling period.

[0105] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain powdered oil (OSAMS-1,3DLG).

[0106] Example 12 Preparation of powdered oil (OSAMS-1,2DMG)

[0107] OSA starch (degree of substitution 0.0147) was prepared into a 5% starch suspension (wt%), and 5% (w / w) 1,2 dimyristoylglycerol (1,2DMG) based on the dry starch was added. The mixture was stirred at 600 rpm for 7 minutes and heated at 90°C for 1.5 hours at 600 rpm. Subsequently, the sample solution was cooled to 20°C at a cooling rate of 0.3°C / min over 4 hours, with a stirring rate of 100 rpm during the cooling period.

[0108] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain powdered oil (OSAMS-1,2DMG).

[0109] Example 13 Preparation of powdered oil (OSAMS-1,3DMG)

[0110] OSA starch (degree of substitution 0.0147) was prepared into a 5% starch suspension (wt%), and 5% (w / w) 1,3 dimyristin (1,3DMG) based on the dry starch was added. The mixture was stirred at 600 rpm for 7 minutes and heated at 90°C for 1.5 hours at 600 rpm. Subsequently, the sample solution was cooled to 20°C at a cooling rate of 0.3°C / min over 4 hours, with a stirring rate of 100 rpm during the cooling period.

[0111] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain powdered oil (OSAMS-1,3DMG).

[0112] Example 14 Preparation of Powdered Grease (OSAMS-1,2DSG)

[0113] OSA starch (degree of substitution 0.0147) was prepared into a 5% starch suspension (wt%), and 5% (w / w) 1,2-distearin (1,2DSG) was added based on the dry starch basis. The mixture was stirred at 600 rpm for 7 minutes and heated at 90°C for 1.5 hours at 600 rpm. Subsequently, the sample solution was cooled to 20°C at a cooling rate of 0.3°C / min over 4 hours, with a stirring rate of 100 rpm during the cooling period.

[0114] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain powdered oil (OSAMS-1,2DSG).

[0115] Example 15 Preparation of powdered oil (OSAMS-1,3DSG)

[0116] OSA starch (degree of substitution 0.0147) was prepared into a 5% starch suspension (wt%), and 5% (w / w) 1,3 distearin (1,3DSG) based on the dry starch was added. The mixture was stirred at 600 rpm for 7 minutes and heated at 90°C for 1.5 hours at 600 rpm. Subsequently, the sample solution was cooled to 20°C at a cooling rate of 0.3°C / min over 4 hours, with a stirring rate of 100 rpm during the cooling period.

[0117] The sample solution was then cooled to 20°C over 4 hours at a cooling rate of 0.3°C / min, with a stirring rate of 100 rpm. The resulting powdered oil sample was centrifuged three times at 5000 g for 10 minutes in n-hexane (powdered oil:n-hexane = 1:2, v / v). The resulting sample was freeze-dried and ground through a 100-mesh sieve to obtain powdered oil (OSAMS-1,3DSG).

[0118] Example 16 H NMR spectra of the examples and comparative samples

[0119] The molecular structure characterization method of powdered oil is as follows:

[0120] The powdered oil was mixed and dispersed evenly with deuterated dimethyl sulfoxide (DMSO-d6) and measured by high field nuclear magnetic resonance. 1 H NMR spectra were acquired using a DMX 300 high-field NMR spectrometer (300 MHz, Bruker, Germany) at 30°C with a pulse angle of 30°, a delay time of 10 s, and an acquisition time of 2 s. All spectra were manually corrected for phase and baseline.

[0121] The samples of the embodiment and the comparative example were measured by hydrogen nuclear magnetic resonance spectroscopy. Figure 2. Compared with Comparative Examples 3 and 4, Examples 4 and 5 showed several new NMR peaks in the region of 0.86-2.26 ppm. Among these new peaks, the signals at 0.86, 1.26-1.60 and 2.2 ppm were the resonances of -CH3, -CH2- and -COCH2- from the ends of the lipid saturated chains, respectively, indicating that dipalmitin esters with different structures had successfully interacted with OSA starch to form a V-shaped crystal structure powdered oil with a single helix encapsulating diglyceride. However, in Comparative Examples 1 and 2 prepared by the general method, the characteristic peaks representing dipalmitin esters did not appear, indicating that Comparative Examples 1-2 did not form a V-shaped crystal structure powdered oil with a specific single helix encapsulating diglyceride.

[0122] Example 17 Long-range crystal ordered structure of the example and comparative example samples (X-ray diffraction)

[0123] The characterization method of the long-range crystal ordered structure of powdered oil is as follows:

[0124] Prior to analysis, the powdered fat was equilibrated in a saturated sodium chloride (NaCl) solution at room temperature (25°C) for 7 days. The long-range crystalline structure of the equilibrated starch samples was then determined using an X-ray diffractometer (D8 ADVANCE, Bruker, Germany) at 40 kV and 40 mA. Scans were performed over the 4-40° (2θ) range at a scan rate of 2° / min and a step size of 0.02°. The relative crystallinity of the powdered fat was calculated using TOPAS 5.0 software.

[0125] Figure 3 X-ray diffraction patterns of the Examples and Comparative Examples are shown. Compared to Comparative Examples 1 and 2, Examples 4 and 5 exhibit two distinct diffraction peaks at 12.8 and 19.8° (2θ), which is attributed to the formation of an OSA starch-diglyceride complex with a V-shaped crystal structure, which is absent in Comparative Examples 1 and 2. As shown in Table 1, the relative crystallinity of Example 4, at 25.7%, is higher than that of Example 5, at 22.3%. This indicates that OSA starch can form a powdered oil with a 1,2-configuration dipalmitoylglycerol complex with a better long-range crystal structure, resulting in greater stability.

[0126] Table 1 Relative crystallinity, infrared absorbance ratio and half-peak width of Examples 3-4 and Comparative Examples 1-2

[0127]

[0128] Note: Data are expressed as mean ± standard deviation. Different lowercase letters indicate significant differences between values in the same column (p < 0.05).

[0129] nd, not detected.

[0130] Example 18 Short-range molecular order of the examples and comparative samples (infrared spectrum, Raman spectrum)

[0131] The characterization method of the short-range molecular order of powdered oils is as follows:

[0132] The Fourier transform infrared spectra of the samples were measured using a Tensor Fourier transform infrared spectrometer (IS50, Thermo Fisher Scientific, USA) equipped with a DLATGS detector. 2 mg of starch sample was accurately weighed and mixed with 150 mg of potassium bromide (KBr), thoroughly ground, and pressed into a transparent disc to form a transparent sheet. The sample was analyzed with air as the background at a wavelength of 4000 to 400 cm -1 The spectrum was recorded between 32 scans with a resolution of 4 cm -1 All spectra were automatically baseline corrected and normalized by OMNIC 9.2 and then centered at 19 cm -1 The deconvolution was performed with a half-peak width of 1.0 and an enhancement factor of 1.9.

[0133] The short-range molecular order changes of the examples and comparative examples were measured by infrared spectrometer. Figure 4 and Table 1. Compared with Comparative Example 1 and Comparative Example 2, Example 4 and Example 5 have the following characteristics: -1 The ratios at 0.681-0.706 are both higher than those of 0.463-0.477 of Comparative Example 1 and Comparative Example 2, indicating that OSA starch interacts with different configurations of dipalmitoylglycerol (1,2 configuration and 1,3 configuration) to form a powdered oil with a single helical V-shaped crystal structure.

[0134] Subsequently, a Raman microscope system (InviaReflex, Renishaw, UK) equipped with a Leica microscope (Leica Biosystems, Wetzlar, Germany) was used to measure the Raman spectra of the samples. First, a small amount of starch sample was placed on a glass slide and pressed into a smooth, opaque sheet. The instrument was then calibrated at 520 cm using a single-crystal silicon wafer. -1 Place the starch sample slice under the microscope field of view, adjust the microscope magnification and focus to select a clear sample field of view for testing. -1 Within the scanning range, a laser with a 785nm green diode laser source is used to collect the spectrum with a resolution of 7cm -1 , laser power 100%. Using WiRE 2.0 software at 480cm -1 The full width at half maximum (FWHM) value data for characterizing the short-range molecular order of starch was obtained.

[0135] The short-range molecular order of the examples and comparative examples was measured by Raman spectroscopy, as shown in Table 1. -1 The half-peak widths at 480 cm-1 and 480 cm-2 were lower than those in Comparative Examples 1 and 2, indicating that OSA starch and dipalmitoylglycerol with different structures (1,2 configuration and 1,3 configuration) formed a powdered oil with stronger short-range molecular order (powdered oil at 480 cm-1). -1 The lower the half-peak width at , the stronger the short-range molecular order is), and the short-range molecular order of Example 4 is better than that of Example 5.

[0136] Example 19 Thermodynamic properties of the examples and comparative examples

[0137] The method for determining the thermodynamic properties of powdered oils is as follows:

[0138] A differential scanning calorimeter (200F3, Netzsch, Germany) equipped with a thermal analysis data station was used to determine the thermodynamic properties of the analyzed samples. 3 mg of starch sample (dry basis) was accurately weighed in an aluminum crucible (40 μL), and then deionized water was added to obtain a sealed crucible with a starch to water mass ratio of 1:3 (w / w). After the aluminum crucible was equilibrated at room temperature for 12 h, it was scanned in the range of 20-100 °C at a heating rate of 10 °C / min, and a blank crucible was used as a blank control. The onset temperature (T o ), peak temperature (T p ), termination temperature (T c ) and enthalpy (△H).

[0139] DSC thermodynamic curves and corresponding thermodynamic transition parameters (T o 、T p , T c and ΔH) see Figure 5 and Table 2. Comparative Examples 1 and 2 did not show melting peaks representing single helical V-type crystal structures, indicating that natural starch could not interact with 1,2 or 1,3 configurations of dipalmitin to form powdered fats. Example 4 showed two endothermic transition peaks at 104.5°C and 124.8°C, respectively, which was due to the formation of V IIa Type and V IIb The enthalpy values of the composites with type crystal structure are 5.0 J / g and 2.3 J / g respectively. Compared with Example 4, there is only one V at 104.7℃ in the DSC curve of Example 5. IIaThe melting peak of the composite with a crystalline structure of type 1 was 7.3 J / g. The above results show that the powdered fats obtained in Examples 4 and 5 have stronger thermal stability than those in Comparative Examples 1 and 2, and the thermal stability of the powdered fat formed in Example 4 is stronger than that in Example 5.

[0140] Table 2 Thermodynamic properties of Examples 4-5 and Comparative Examples 1-2

[0141]

[0142] Note: Data are presented as mean ± standard deviation. Different lowercase letters indicate significant differences (p < 0.05) between values in the same column. nd, not detected.

[0143] Example 20 Morphology and structure diagram of example and comparative example samples

[0144] The morphology and structure characterization methods of powdered oils are as follows:

[0145] The morphological structure images of the stained samples were observed and photographed using a laser confocal scanning microscope (Leica TCSSP5, Leica Microsystems, Germany). Approximately 15 mg of sample was thoroughly mixed with 1 mL of Nile red solution (0.1%, w / w, dissolved in acetone) and 1 mL of Nile blue solution (0.1%, w / w, dissolved in deionized water). The mixed sample was stained in the dark at 4°C and centrifuged after 24 hours (4200g, 15min). The precipitate was washed with acetone and deionized water to remove excess dye and improve resolution. The stained sample was placed on a concave slide and covered with a glass coverslip. The fluorescence of the sample was excited with 488nm Ar and 633nm He / Ne lasers.

[0146] The examples and comparative examples were stained using a laser confocal microscope to observe their morphological structures. Green fluorescence represents starch, red fluorescence represents dipalmitoylglycerol (1,2 configuration and 1,3 configuration), and yellow represents starch-diacylglycerol complex. Figure 6 As shown, only irregular block-shaped starch was present in Comparative Examples 1 and 2, with no red fluorescence representing diglyceride and no yellow fluorescence representing the complex powdered fat. This indicates that no powdered fat with a V-type crystal structure was present in Comparative Examples 1 and 2. However, red fluorescence representing diglyceride and rod-shaped powdered fat with yellow fluorescence were present in Examples 4 and 5, indicating that powdered fat with a stable V-type crystal structure was produced in Examples 4 and 5. The structure size of Example 4 was stronger and larger than that of Example 5.

[0147] Example 21 Molecular Force Analysis of Example Samples

[0148] In Examples 4 and 5, the main interaction forces between OSA starch and diacylglycerols of different configurations in diacylglycerol-rich powdered oils were analyzed by molecular dynamics simulation technology. Figure 7 As shown in the figure, the main interaction forces between OSA starch and diacylglycerol with different configurations are van der Waals force, electrostatic interaction and hydrophobic interaction.

[0149] Example 22 Digestion curves of examples and comparative examples

[0150] The in vitro digestibility characteristics of powdered fats and oils were determined as follows:

[0151] 100 mg of sample (dry basis) was accurately weighed and dispersed in 9 mL of sodium acetate buffer containing 6.67 mmol / L CaCl₂. 1 mL of freshly prepared porcine pancreatic α-amylase solution (160 U) was added. The reaction was continued in a 37°C water bath at 260 rpm for 300 min. At specific time points (0, 5, 10, 20, 30, 40, 50, 60, 90, 120, 180, 240, and 300 min), 100 μL of the digestion solution was collected and mixed with 900 μL of 0.5 M Na₂CO₃ to inactivate the α-amylase. The supernatant was then centrifuged at 13,000 g for 4 min. The reducing sugar content of the supernatant was determined using the hydroxybenzoic acid hydrazide (PAHBAH) method. A standard curve ranging from 3.91 to 1000 μg / mL was constructed using a maltose standard. The hydrolysis rate (%) was calculated using the following formula:

[0152]

[0153] Among them C rs is the concentration of reducing sugars (mg / mL), D is the dilution factor, V is the volume of the digestion fluid (mL), and SW is the weight of the starch sample (mg)

[0154] Figure 8 The in vitro digestion curves of the examples and comparative examples are shown. The final digestion levels for Comparative Examples 1 and 2 were 70.6%-71.8%. In comparison, the final in vitro digestion levels for Examples 4 and 5 were significantly lower, at 55.8%-57.1%, indicating that the powdered fats obtained in Examples 4 and 5 have stronger enzyme resistance and lower digestibility.

[0155] Example 23 Analysis of emulsification properties of examples and comparative examples

[0156] The emulsifying activity and emulsifying stability of Example 1 and Examples 4-5, Comparative Examples 1-2 and Comparative Example 5 are shown in Table 3. Compared with Comparative Example 5, the emulsifying activity and emulsifying stability of Example 1 were significantly improved by OSA modification. Compared with Comparative Examples 1-2, Examples 4-5 have stronger emulsifying properties. In addition to the reasons for OSA modification, the introduction of hydrophobic diglyceride also further increases its hydrophobicity. The emulsifying activity and emulsifying stability of Example 4 are better than those of Example 5, which may be attributed to the difference in emulsifying properties caused by the different structures of 1,2DPG and 1,3DPG.

[0157] Table 3 Emulsification properties of Examples 1 and 4-5, Comparative Examples 1-2 and 5

[0158]

[0159] Note: Data are presented as mean ± standard deviation. Different lowercase letters indicate significant differences (p < 0.05) between values in the same column. nd, not detected.

[0160] Example 24 Oxidative Stability Analysis of Diglycerides in Example and Comparative Example Samples

[0161] The oxidative stability of diglycerides in powdered oils and fats is determined as follows:

[0162] Accelerated test for oxidation stability

[0163] To evaluate the effect of powdered oil on the oxidative stability of diacylglycerols, samples were stored in sealed transparent glass bottles in the dark at 50°C and 50% relative humidity for 15 days to accelerate oxidation. At days 0, 3, 6, 9, 12, and 15, 1 g of each sample was accurately weighed, added to 10 mL of deionized water and 5 mL of 0.5 M hydrochloric acid, mixed thoroughly, and heated in a 70°C water bath for 1 h. After cooling to room temperature, 15 mL of petroleum ether and anhydrous ether were added, mixed thoroughly, and the supernatant was collected by filtration in a rotary evaporator. This step was repeated three times. The resulting supernatant was rotary evaporated at 40°C to remove the oil from the sample, flushed with N2, and dried for use in determining the peroxide value (POV) and thiobarbituric acid reactive substances (TBARS) of the diacylglycerols in the sample. The specific steps are as follows.

[0164] (1) POV determination

[0165] Accurately weigh 10 mg of diacylglycerol extracted from each sample into a 5 mL test tube. Add 3 mL of a methanol / n-butanol mixture (2:1, v / v) and mix thoroughly. Subsequently, add 15 μL of ammonium bisulfate solution (3.94 M) and 15 μL of ferrous chloride solution (0.072 M). Mix thoroughly and incubate in the dark for 20 minutes. Measure the sample's absorbance at 510 nm and calculate the diacylglycerol peroxide value according to the following formula.

[0166]

[0167] Among them A s and A b are the absorbance values of the sample and blank, respectively, and M is Fe 3+ The slope of the standard curve, M0 is the mass of the sample.

[0168] (2) Determination of TBARS

[0169] Accurately weigh 10 mg of diacylglycerol extracted from each sample into a 10 mL test tube. Add 0.7 mL of deionized water and 1 mL of TBA reagent, mix thoroughly, and heat in a 90°C water bath for 30 minutes. After cooling to room temperature, add 5 mL of chloroform, centrifuge at 3500 g for 10 minutes, and discard the supernatant. After incubation at room temperature for 10 minutes, measure the absorbance of the sample at 532 nm. Determine the concentration of TBARS in diacylglycerol using a standard curve prepared with 1,1,3,3-tetraethoxypropane.

[0170] Figure 9 and Figure 10 The graph shows the changes in POV and TBARS levels of Examples 4-5 and Comparative Examples 1-4 and Comparative Example 6 at 50°C over storage time. Comparative Examples 3 and 4 are natural, unprotected diglycerides. As storage time increases, their POV and TBARS values gradually increase to reach maximum values. Compared with Comparative Examples 1-4 and Comparative Example 6, the POV and TBARS values of the diglycerides in Examples 4 and 5 are both the lowest. The above data show that the obtained powdered oil has a good antioxidant protection effect on diglycerides of different configurations, significantly improving the oxidative stability of diglycerides. Its antioxidant protection effect on functional diglycerides is significantly better than previous methods (such as Comparative Example 6, etc.).

[0171] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

[0172] All structural changes made based on the concept of the present invention without creative work fall within the scope of protection of the present invention.

Claims

1. A powdered fat prepared from modified starch and lipid, wherein the powdered fat has an X-ray diffraction pattern with peaks at 12.8° and 19.8°.

2. The powdered fat according to claim 1, wherein the relative crystallinity is 22.3-25.7%, the short-range molecular order in infrared spectrum is 0.68-0.71, and the short-range molecular order in Raman spectrum is 15.21-15.

56.

3. The powdered fat according to claim 2, having a rod-like morphology and structure, with a width of about 13.57-17.86 μm and a length of about 31.43-42.14 μm.

4. The powdered fat according to claim 1, characterized in that Enzyme resistance 55.8-57.1%.

5. powdered oil according to claim 1, wherein the POV range is 3.91-4.12 mmol / kg, and the TBARS range is 3.05-3.15 μmol / kg.

6. The powdered oil according to claim 1, wherein the modified starch is OSA starch; and the oil is selected from glycerides and polyunsaturated fatty acids.

7. The powdered fat according to claim 6, characterized in that OSA starch: It is obtained by esterification modification reaction of corn starch with A-type crystal structure, potato starch with B-type crystal structure, and pea starch with C-type crystal structure, or more than one of them as raw materials.

8. The powdered fat according to claim 7, characterized in that The degree of substitution of OSA starch is 0.0147-0.0486.

9. The multifunctional powdered oil according to claim 6, characterized in that The glycerides are selected from diglycerides.

10. The powdered fat according to claim 9, characterized in that The diglyceride is selected from: any one or more of 1,2-configuration diglyceride and 1,3-configuration diglyceride.

11. The powdered fat according to claim 10, characterized in that The diglyceride is selected from: 1,2-configuration diglyceride is 1,2-configuration dilaurin, 1,2-configuration dimyristin, 1,2-configuration dipalmitin, 1,2-configuration distearin; 1,3-configuration dilaurin, 1,3-configuration dimyristin, 1,3-configuration dipalmitin, 1,3-configuration distearin.

12. The powdered fat according to claim 11, characterized in that The diglyceride is selected from: any one or more of 1,2-configuration dipalmitin glyceride and 1,3-configuration dipalmitin glyceride.

13. A method for preparing the powdered fat according to any one of claims 1 to 12, characterized in that: The modified starch and lipid are bound via non-covalent interactions.

14. The method for preparing the powdered fat according to claim 13, wherein: (1) OSA modification of natural starch to obtain OSA starch; (2) preparing an OSA starch suspension, adding diglyceride, and heating; (3) Cooling under controlled temperature, centrifugation with ethanol precipitation, and drying.

15. The preparation method according to claim 14, characterized in that: (1) Dispersing natural starch in a deionized water solution, adding an OSA modifying agent after heating, adjusting the pH value, controlling the OSA modifying agent to be added dropwise within a certain period of time, continuously stirring for modification, and then centrifuging to obtain a precipitate, i.e., OSA starch; (2) Add diglyceride to the OSA starch suspension and continue magnetic stirring. Heat to 90°C and stir thoroughly to obtain a powdered oil sample solution. (3) The powdered oil sample solution was stirred and cooled to 20°C. The cooled powdered oil sample solution was then precipitated with anhydrous ethanol at a ratio of 1:4 (v / v) for 15 h. The precipitate was centrifuged at 3000 g for 8 min. The precipitate was dried for 12 h and ground through a 100-mesh sieve to obtain the powdered oil.

16. The preparation method according to claim 15, characterized in that: In step (1), the natural starch is corn starch, the amount of OSA modification agent added is 3-9% based on the dry weight of the starch, the reagent addition time is continuous for 1-1.5 hours, and the reaction is continued for 2-3 hours, during which the pH value is adjusted to 7.5-8.0 and the stirring rate is 900-1200 rpm; In step (2), the concentration of the starch suspension is 5-10% (wt%), the diglyceride is 5-8% (w / w) based on the dry basis of the starch, the stirring speed is 600-800 rpm, the duration is 7-9 minutes, and the heating reaction is continued for 1.5-2.5 hours, during which the rotation speed is 500-800 rpm; In the step (3), the powdered oil sample solution is cooled to 70° C. within 3-4 hours at a cooling rate of 0.3-0.4° C. / min, and the stirring rate during the cooling period is 100-200 rpm.

17. Use of the powdered oil according to any one of claims 1 to 12 in foods for special medical purposes, functional foods, and nutritional additives.

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