Stable and efficient OSA starch-grease novel composite resistant starch, and one-step method induction preparation and application thereof

Abstract

The invention belongs to the field of food processing and food nutrition, and particularly relates to stable and efficient OSA starch-grease novel composite resistant starch, including starch-triglyceride novel composite resistant starch, a one-step induction preparation process and application thereof, and application of the starch-triglyceride novel composite resistant starch in high-resistance special medical food for correspondingly regulating and controlling blood sugar. The invention innovatively provides the process stages of melting reaction, cooling compounding and the like in the compound preparation process through precise regulation and control, the starch-triglyceride compound with a typical VII type crystal structure is prepared through efficient induction for the first time, and the starch-triglyceride compound is high in thermal stability and high in processing adaptability. Furthermore, the starch-coconut oil special medical food is prepared through one-step induction, and the starch-coconut oil special medical food has high digestion resistance and can regulate and control the change of the blood sugar function. Compared with a starch-triglyceride compound which cannot be obtained by a traditional process, the preparation method disclosed by the invention has the advantages that not only is the starch-triglyceride compound efficiently prepared, but also the quality is better, and the improvement of food quality and the regulation and improvement of human blood sugar health are more facilitated.

Description

Technical Field

[0001] The present invention belongs to the fields of food processing and food nutrition, specifically to a stable and efficient new OSA starch-oil composite resistant starch, including a starch-triglyceride composite resistant starch, a one-step induction preparation process and its application in fields such as special medical foods. This composite resistant starch also has the ability to regulate blood sugar, among other properties. Background Art

[0002] Increasing dietary fiber intake can prevent and control the onset of chronic diseases to a certain extent, providing an ideal, low-cost, and sustainable approach. Starch-lipid complexes, also known as RS5 resistant starch, are a special type of dietary fiber and have attracted widespread attention due to their unique functional and nutritional health properties.

[0003] Starch-lipid complexes (SLCs) are supramolecular single helical structures formed primarily by the self-assembly of amylose and lipids during thermal processing. They are ubiquitous in processed starchy foods. Their formation and structural stability are influenced by a variety of factors, including the starch source, lipid structure, and preparation conditions. The alkyl chain length, degree of unsaturation, and solubility of the lipids influence the structural and functional properties of SLCs. Studies have shown that fatty acids, monoglycerides, and diglycerides can form single helical SLCs with processed starch. However, edible oils, primarily triglycerides in our daily diet, are difficult to complex with due to their strong hydrophobicity and structural complexity, significantly limiting their application and development in nutritional and health-enhancing foods for special medical use. Finding new methods to promote the complex interaction between starch and edible oils (triglycerides) to form complexes that better meet food quality and human nutritional health needs has become a critical issue in the fields of food processing and nutrition.

[0004] Based on this dilemma, the inventors proposed a one-step method to induce the efficient preparation of starch-triglyceride complexes with stable structures and blood sugar regulation functions, and their corresponding special medical foods, by changing the hydrophobicity of starch itself and regulating the parameters of starch and edible oil (triglycerides) during the melting and compounding stages. The patented method of this invention is highly efficient, produces high-quality products, has good application prospects and development potential, and is suitable for large-scale industrial production. At the same time, it is low-cost and is expected to play a role in improving or alleviating chronic diseases such as diabetes, three highs, and obesity.

[0005] Glossary:

[0006] V IIType single helix crystal structure: Driven by hydrophobic forces, the triglyceride hydrophobic chain enters the helical cavity of amylose, thereby forming a left-handed single helical molecule with a highly ordered crystal structure; subsequently, a large number of OSA starch-triglyceride molecules are further arranged and stacked in an orderly manner to form a crystal structure.

[0007] OSA starch: Octenyl Succiniate anhydrate starch, octenyl succinate starch ester.

[0008] Glyceryl trilaurate: CAS: 538-24-9; trilaurin; Chinese alias: trilaurin, trilaurin, 1,2,3-propylene glycol tri(dodecanoate), laurin. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to propose a stable and efficient OSA starch-oil new composite resistant starch, including a starch-triglyceride new composite resistant starch, its one-step induction preparation process and application, and its application in high-resistant special medical foods corresponding to blood sugar regulation.

[0010] The present invention innovatively proposes to precisely control the melting reaction, cooling and compounding process in the preparation of the composite, and for the first time efficiently induces the preparation of a typical V II The starch-triglyceride complex has a type crystalline structure and has high thermal stability and strong processing adaptability.

[0011] Furthermore, the method of the present invention is used to induce the preparation of starch-coconut oil special medical foods in a one-step process. These foods have strong digestion resistance and can regulate changes in blood sugar function. Compared with traditional processes that cannot produce starch-triglyceride complexes, the patented method of the present invention not only efficiently prepares starch-triglyceride complexes, but also has better quality, which is more conducive to improving food quality and regulating human blood sugar health.

[0012] The OSA starch-oil composite resistant starch of the present invention comprises an oil selected from one or more of edible oil and triglyceride; further, the oil is selected from one or more of coconut oil and trilaurin.

[0013] The novel starch-triglyceride composite resistant starch of the present invention has a typical type VII single helical crystal structure, with XRD characteristic diffraction peaks at 12.8° and 19.8°, a relative crystallinity of 15.8-22.3%, and a short-range molecular ordered structure at 1047 / 1022cm -1 The infrared absorbance ratio at 480 cm is 0.67-0.76. -1 The half-peak width at 17.34-15.08.

[0014] The OSA starch-oil composite resistant starch of the present invention has an OS group substitution degree in the OSA starch of 0.010 to 0.040; further, an OS group substitution degree in the OSA starch of 0.0150 to 0.035; preferably 0.0161 to 0.0318.

[0015] The OSA starch-oil composite resistant starch of the present invention has a mass ratio of OSA starch to trilaurin of 1:0.01 to 0.10; further, the mass ratio of OSA starch to trilaurin is 1:0.04 to 0.08.

[0016] The present invention provides a stable and efficient one-step induction preparation process for a novel starch-triglyceride composite resistant starch. To achieve the above objectives, the technical solution created by the present invention is implemented as follows:

[0017] (1) Pre-mixing stage: Add oil to starch suspension, and mix starch and oil thoroughly by ultrasonic combined with magnetic stirring;

[0018] (2) Heating and melting stage: The mixed starch-oil suspension is heated in a water bath, reacted at a controlled temperature and magnetically stirred for 2 h;

[0019] (3) Cooling and compounding stage: The starch-oil reaction system is subjected to a gradient cooling treatment, and the uncompounded oil in the starch paste is washed with anhydrous ethanol precipitation, freeze-dried, and ground to obtain a new type of starch-triglyceride composite resistant starch.

[0020] Furthermore, in the novel starch-triglyceride composite resistant starch, the starch is selected from OSA starch, and the oil is selected from triglyceride.

[0021] Furthermore, in the novel starch-triglyceride composite resistant starch, the degree of substitution of OS groups in OSA starch is 0.0161-0.0318, the oil is selected from trilaurin, and the mass ratio of OSA starch to trilaurin is 1:0.04-0.08.

[0022] Furthermore, the concentration of the OSA starch suspension of the novel starch-triglyceride composite resistant starch is 5% to 8%.

[0023] Furthermore, the novel starch-triglyceride composite resistant starch has an ultrasonic power range of 100-300 W, an ultrasonic treatment interval time of 4-12 s / min (ultrasonic time / stirring time), a magnetic stirring speed of 300-600 rpm, and a stirring time of 5 min.

[0024] Furthermore, the starch-triglyceride novel composite resistant starch is prepared by heating the reaction system to 90°C at a rate of 5°C / min, maintaining the internal temperature of the system at 90±1°C, and stirring at a magnetic stirring speed of 1000-1500 rpm.

[0025] Furthermore, the starch-triglyceride novel composite resistant starch has a magnetic stirring rate of 100-150 rpm, and during the cooling and compounding stage, the starch paste is gradually cooled from 90°C to 20°C within 4 hours. After the starch paste is treated with anhydrous ethanol in a volume ratio of 1:2 to 5, the supernatant is removed, the paste is quick-frozen in liquid nitrogen for 5 minutes, and then freeze-dried at -80°C and ground through a 100-mesh sieve.

[0026] Furthermore, the starch-triglyceride novel composite resistant starch has a gradient cooling process of 4 steps: from 90°C to 75°C within 0-0.5h; from 75°C to 50°C within 0.5-1h; from 50°C to 30°C within 1-3h; and from 30°C to 20°C within 3-4h.

[0027] The starch-edible oil special medical food rich in OSA starch-trilaurin novel composite resistant starch of the present invention comprises the following steps:

[0028] (1) OSA starch with a specific degree of substitution, edible oil, and water are mixed thoroughly to obtain a mixture;

[0029] (2) heating the mixture in (1) above in a water bath for 2 h;

[0030] (3) The obtained starch paste is subjected to gradient cooling treatment, freeze-dried and ground to obtain the corresponding special medical food.

[0031] Furthermore, in the starch-edible oil special medical food, the edible oil is selected from coconut oil.

[0032] The OSA starch-oil composite resistant starch and related special medical foods described in the present invention have significant enzyme resistance and low digestibility; the low digestibility is less than 70%; further, the low digestibility is less than 60%, for example, about 53.3%.

[0033] The OSA starch-oil composite resistant starch of the present invention can be used to prepare common food, special medical food and functional food.

[0034] Compared with the traditional method, the present invention has the following advantages and effects:

[0035] The present invention overcomes the bottleneck of the traditional method that cannot prepare starch-triglyceride complex, and provides a method for preparing starch-triglyceride with simple preparation process, easy operation and no need of any external additives. The novel composite resistant starch of starch triglyceride prepared by the present invention has typical V IIThe crystalline structure is characterized by high thermal stability and strong processing adaptability. Through a one-step method, a special medical food made from starch and edible oil is efficiently induced and prepared. This food is resistant to amylase digestion, lowers the glycemic index of the food, and has the function of regulating blood sugar. This is of great significance for improving the nutritional health of people with chronic diseases such as diabetes, three highs, and obesity.

[0036] 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

[0037] Figure 1 The hydrogen nuclear magnetic resonance spectra of Examples 2-4 and Comparative Examples 1-2 are shown;

[0038] Figure 2 The X-ray diffraction patterns of Examples 2-4 and Comparative Example 1 are shown;

[0039] Figure 3 The following are Fourier transform infrared spectra of Examples 2-4 and Comparative Example 1;

[0040] Figure 4 The differential scanning calorimeter diagrams of Examples 2-4 and Comparative Example 1;

[0041] Figure 5 The 1H NMR spectra of Example 5 and Comparative Examples 3-4 are shown;

[0042] Figure 6 The X-ray diffraction patterns of Example 5 and Comparative Example 3 are shown;

[0043] Figure 7 The Fourier transform infrared spectra of Example 5 and Comparative Examples 3-4 are shown;

[0044] Figure 8 The differential scanning calorimeter diagrams of Example 5 and Comparative Example 3 are shown;

[0045] Figure 9 It is the in vitro digestion curve diagram of Example 5 and Comparative Example 3. DETAILED DESCRIPTION

[0046] 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.

[0047] Example 1 Preparation of OSA starch (native corn starch source)

[0048] The OSA starch used in the following examples can be prepared by the following method:

[0049] 15g (dry weight) of native corn starch was accurately weighed to prepare a 25% starch suspension (wt%). An OSA modifier (3-9% by weight, 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.

[0050] Example 2 Preparation of a new starch-triglyceride composite resistant starch (OS group ratio is 0.0161)

[0051] (1) Pre-premixing stage: Use OSA corn starch with an OS group ratio of 0.0161 to prepare a starch suspension of 7% (wt%), add trilaurin (ratio of 1:0.06, w / w), and use ultrasound combined with magnetic stirring to fully mix the starch and oil. The ultrasonic power is 150 W, the ultrasonic treatment interval is 12 s / min (ultrasound time / stirring time), the magnetic stirring is 600 rpm, and the stirring time is 5 min.

[0052] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0053] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0054] Example 3 Preparation of a new starch-triglyceride composite resistant starch (OS group ratio is 0.0236)

[0055] (1) Pre-premixing stage: OSA corn starch with an OS group ratio of 0.0236 was used to prepare a starch suspension of 7% (wt%), trilaurin was added (ratio of 1:0.06, w / w), and the starch and oil were fully mixed by ultrasonic combined with magnetic stirring. The ultrasonic power was 150 W, the ultrasonic treatment interval was 12 s / min (ultrasonic time / stirring time), the magnetic stirring was 600 rpm, and the stirring time was 5 min.

[0056] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0057] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0058] Example 4 Preparation of a Novel Starch-Triglyceride Composite Resistant Starch (OS Group Ratio is 0.0318)

[0059] (1) Pre-premixing stage: OSA corn starch with an OS group ratio of 0.0318 was used to prepare a starch suspension of 7% (wt%), trilaurin was added (ratio of 1:0.06, w / w), and the starch and oil were fully mixed by ultrasonic combined with magnetic stirring. The ultrasonic power was 150 W, the ultrasonic treatment interval was 12 s / min (ultrasonic time / stirring time), the magnetic stirring was 600 rpm, and the stirring time was 5 min.

[0060] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0061] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0062] Example 5 Preparation of a new type of starch-edible oil (coconut oil) composite resistant starch (OS group ratio is 0.0318)

[0063] (1) Pre-premixing stage: OSA corn starch with an OS group ratio of 0.0318 was used to prepare a starch suspension of 7% (wt%), and coconut oil was added (ratio of 1:0.06, w / w). The starch and oil were fully mixed by ultrasonic combined with magnetic stirring. The ultrasonic power was 150 W, the ultrasonic treatment interval was 12 s / min (ultrasonic time / stirring time), the magnetic stirring was 600 rpm, and the stirring time was 5 min.

[0064] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0065] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncompounded oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-coconut oil composite resistant starch.

[0066] Comparative Example 1

[0067] (1) Pre-premixing stage: A starch suspension containing 7% (wt%) of natural corn starch with 0 OS group was prepared, trilaurin was added (ratio of 1:0.06, w / w), and the starch and oil were fully mixed by ultrasonic combined with magnetic stirring. The ultrasonic power was 150 W, the ultrasonic treatment interval was 12 s / min (ultrasonic time / stirring time), the magnetic stirring was 600 rpm, and the stirring time was 5 min.

[0068] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0069] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0070] Comparative Example 2

[0071] Trilaurin was not treated in any way and was used as one of the control samples of the present invention.

[0072] Comparative Example 3

[0073] (1) Pre-premixing stage: A starch suspension containing 7% (wt%) of natural corn starch with 0 OS group was prepared, and coconut oil was added (ratio of 1:0.06, w / w). The starch and oil were fully mixed by ultrasonic combined with magnetic stirring. The ultrasonic power was 150 W, the ultrasonic treatment interval was 12 s / min (ultrasonic time / stirring time), the magnetic stirring was 600 rpm, and the stirring time was 5 min.

[0074] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0075] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncompounded oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-coconut oil composite resistant starch.

[0076] Comparative Example 4

[0077] Coconut oil, without any treatment, was used as one of the control samples of the present invention.

[0078] Example 6 Preparation of a Novel Starch-Triglyceride Composite Resistant Starch (OS Group Ratio is 0.0161, Trilaurin Ratio is 1:0.04 (w / w))

[0079] (1) Pre-premixing stage: OSA corn starch with an OS group ratio of 0.0161 was used to prepare a starch suspension of 7% (wt%), trilaurin was added (ratio of 1:0.04, w / w), and the starch and oil were fully mixed by ultrasonic combined with magnetic stirring. The ultrasonic power was 150 W, the ultrasonic treatment interval was 12 s / min (ultrasonic time / stirring time), the magnetic stirring was 600 rpm, and the stirring time was 5 min.

[0080] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0081] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0082] Example 7 Preparation of a Novel Starch-Triglyceride Composite Resistant Starch (OS Group Ratio is 0.0161, Trilaurin Ratio is 1:0.08 (w / w))

[0083] (1) Pre-premixing stage: Use OSA corn starch with an OS group ratio of 0.0161 to prepare a 7% (wt%) starch suspension, add trilaurin (ratio of 1:0.08, w / w), and use ultrasound combined with magnetic stirring to fully mix the starch and oil. The ultrasonic power is 150 W, the ultrasonic treatment interval is 12 s / min (ultrasound time / stirring time), the magnetic stirring is 600 rpm, and the stirring time is 5 min.

[0084] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0085] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0086] Example 8 Preparation of a Novel Starch-Triglyceride Composite Resistant Starch (OS Group Ratio is 0.0161, OSA Starch Suspension Ratio is 5%)

[0087] (1) Pre-premixing stage: Use OSA corn starch with an OS group ratio of 0.0161 to prepare a 5% (wt%) starch suspension, add trilaurin (ratio of 1:0.06, w / w), and use ultrasound combined with magnetic stirring to fully mix the starch and oil. The ultrasonic power is 150 W, the ultrasonic treatment interval is 12 s / min (ultrasound time / stirring time), the magnetic stirring is 600 rpm, and the stirring time is 5 min.

[0088] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0089] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0090] Example 9 Preparation of a Novel Starch-Triglyceride Composite Resistant Starch (OS Group Ratio is 0.0161, OSA Starch Suspension Ratio is 8%)

[0091] (1) Pre-premixing stage: Use OSA corn starch with an OS group ratio of 0.0161 to prepare an 8% (wt%) starch suspension, add trilaurin (ratio of 1:0.06, w / w), and use ultrasound combined with magnetic stirring to fully mix the starch and oil. The ultrasonic power is 150 W, the ultrasonic treatment interval is 12 s / min (ultrasound time / stirring time), the magnetic stirring is 600 rpm, and the stirring time is 5 min.

[0092] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0093] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0094] Example 10 Preparation of a Novel Starch-Triglyceride Composite Resistant Starch (Ultrasonic Treatment Interval 4 s / min (Ultrasonic Time / Stirring Time))

[0095] (1) Pre-premixing stage: OSA corn starch with an OS group ratio of 0.0161 was used to prepare a starch suspension of 7% (wt%), trilaurin was added (ratio of 1:0.06, w / w), and the starch and oil were fully mixed by ultrasonic combined with magnetic stirring. The ultrasonic power was 150 W, the ultrasonic treatment interval was 4 s / min (ultrasonic time / stirring time), the magnetic stirring was 600 rpm, and the stirring time was 5 min.

[0096] (2) Heating and melting stage: The mixed starch-oil suspension was heated in a water bath. The reaction system was heated to 90°C at a rate of 5°C / min, and the internal temperature of the system was maintained at 90±1°C. The magnetic stirring speed was 1500 rpm. The temperature was controlled and the magnetic stirring was continued for 2 h.

[0097] (3) Cooling and compounding stage: The starch-oil reaction system was cooled gradually from 90°C to 20°C within 4 hours, with a total of 4 steps: from 90°C to 75°C within 0-0.5 hours; from 75°C to 50°C within 0.5-1 hours; from 50°C to 30°C within 1-3 hours; and from 30°C to 20°C within 3-4 hours. During this period, magnetic stirring was maintained at 100 rpm. The uncomplexed oil in the starch paste was washed with anhydrous ethanol at a volume ratio of 1:2 (v / v). The supernatant was removed, and the mixture was quick-frozen in liquid nitrogen for 5 minutes, then freeze-dried at -80°C, and ground through a 100-mesh sieve to obtain a new starch-triglyceride composite resistant starch.

[0098] Example 11 Examples 2-4 and Comparative Examples 1-2 1 H-NMR spectrum

[0099] The molecular structure characterization method of OSA starch-trilaurin novel composite resistant starch and its special medical food is as follows:

[0100] OSA starch-trilaurin new composite resistant starch and its special medical food were 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 DMX300 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.

[0101] The samples of Examples 2-4 and Comparative Examples 1-2 were subjected to H NMR spectroscopy. Figure 1. Compared with Comparative Examples 1 and 2, Examples 2-4 show several characteristic NMR peaks representing triglycerides in the region of 0.86-1.68 ppm. Among these new peaks, the NMR peaks at 0.86 and 1.26-1.60 ppm are the resonances of -CH3 and -CH2- from the saturated chain ends of triglycerides, respectively, indicating that triglycerides have been successfully complexed with OSA starch, while native starch cannot form a binary complex with triglycerides. As the degree of substitution of OSA starch increases, the hydrogen proton peaks of the composite samples at 0.86 and 1.26-1.60 ppm gradually increase, indicating that the number of OSA starch-triglyceride complexes increases.

[0102] Example 12 Long-range crystal ordered structure of Examples 2-4 and Comparative Example 1 (X-ray diffraction)

[0103] The long-range crystal ordered structure characterization method of OSA starch-trilaurin novel composite resistant starch and its special medical food is as follows:

[0104] Prior to analysis, the OSA starch-trilaurin resistant starch composite and its FSMP food were 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 OSA starch-trilaurin resistant starch composite and its FSMP food was calculated using TOPAS 5.0 software.

[0105] Figure 2 The XRD patterns of the samples of Examples 2-4 and Comparative Example 1 are shown. Compared with Comparative Example 1, Examples 2-4 show two obvious diffraction peaks at 12.8 and 19.8° (2θ). The crystallinity of the composite sample gradually increases with the increase of the OSA addition ratio of the modified starch, from 15.8% to 22.3% (Table 1), indicating that more lipids are involved in the formation of the composite. This is attributed to the fact that OSA modification improves the emulsification of natural starch, which in turn facilitates the dispersion of triglycerides in the reaction aqueous phase system and promotes the complex interaction of more triglycerides and OSA starch.

[0106] Table 1 Relative crystallinity (RS), infrared absorbance ratio and half-peak width of Examples 2-4 and Comparative Example 1

[0107]

[0108] Note: Data are expressed as mean ± standard deviation. Different lowercase letters indicate significant differences between values in the same column (p < 0.05).

[0109] nd, not detected.

[0110] Example 13 Short-range molecular order of Examples 2-4 and Comparative Example 1 (Infrared spectroscopy + Raman spectroscopy)

[0111] The characterization method of the short-range molecular order of OSA starch-trilaurin novel composite resistant starch and its special medical food is as follows:

[0112] 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.

[0113] Figure 3 The FITR spectra of the samples of Examples 2-4 and Comparative Example 1 are shown. Compared with Comparative Example 1, the infrared spectra of Examples 2-4 at 1710 and 2857 cm -1 There are two new spectral peaks at about 1701 cm -1 It showed absorption at 1734 cm due to the formation of starch-lipid complex. -1 The higher value ( Figure 3 ). In the binary complex, the absorption of CH asymmetric stretching vibration of the lipid methylene group changes from 2851 cm -1 Blue shift to 2857 cm -1 These results demonstrate the successful preparation of starch-triglyceride complexes.

[0114] The changes in the short-range molecular order of the samples of Examples 2-4 and Comparative Example 1 were measured by infrared spectroscopy. As shown in Table 1, the short-range molecular order of the samples of Examples 2-4 and Comparative Example 1 prepared with different degrees of substitution OSA starch was quantified at 1047 / 1022 cm -1 The infrared absorbance ratios of the OSA starch and trilaurin were 0.67, 0.71 and 0.76, respectively, which were much higher than 0.49 of Comparative Example 1, indicating that the short-range molecular order of the complex formed by OSA starch and trilaurin was gradually increasing.

[0115] The Raman spectra of the samples were measured using a Raman microscope system (Invia Reflex, Renishaw, UK) equipped with a Leica microscope (Leica Biosystems, Wetzlar, Germany). 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.

[0116] Subsequently, the structures of the samples of Examples 2-4 and Comparative Example 1 were further determined by Raman spectroscopy. -1 The lower the FWHM value at , the higher the degree of short-range molecular order of the complex or the greater the number of complexes. Compared with Comparative Example 1, the FWHM of Examples 2-4 is significantly reduced. As the degree of substitution increases (0.0161-0.0318), the FWHM values of Examples 2-4 samples decrease from 17.34 to 15.08, indicating that their short-range molecular order gradually increases.

[0117] Example 14 Thermodynamic properties of Examples 2-4 and Comparative Example 1

[0118] The thermodynamic properties of OSA starch-trilaurin novel composite resistant starch and its special medical food are determined as follows:

[0119] 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 hours, 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) of the new composite resistant starch of OSA starch-trilaurin and its special medical food was calculated using Proteus analysis software. o ), peak temperature (T p ), termination temperature (T c) and enthalpy (ΔH).

[0120] Figure 4 Table 2 shows the DSC thermodynamic curves and corresponding thermodynamic transition parameters (T o 、T p , T c and ΔH). All samples showed a DSC melting peak around 40-50 °C, which was attributed to the thermal decomposition of uncomplexed trilaurin. Figure 4 It can be seen that the crystal melting peak representing the composite does not appear in Comparative Example 1, while V appears in Examples 2-4. Ⅱ The melting peak of the complex with a type crystal structure indicates that OSA starch can interact with trilaurin and form a starch-triglyceride binary complex, while trilaurin cannot form a complex with native starch. The enthalpy value of the starch-lipid complex is considered to reflect the amount of the complex and, to a lesser extent, the structural order of the complex. Compared with Comparative Example 1, the high enthalpy values of Examples 2-4 (3.3-7.5 J / g) indicate that the examples prepared by the patented method of the present invention can promote the formation of more complexes than the traditional method, and the complex prepared by OSA starch and trilaurin has V Ⅱa and V Ⅱb As the degree of substitution of OSA starch increases from 0.0161 to 0.0318, the enthalpy values (3.3-7.5 J / g) and T p The temperature gradually increased (105.6-126.9℃), indicating that it was able to form more OSA starch-triglyceride complexes with good crystal structure.

[0121] Table 2 Thermodynamic properties of Examples 2-4 and Comparative Example 1

[0122]

[0123] Note: Data are expressed as mean ± standard deviation. Different lowercase letters indicate significant differences between values in the same column (p < 0.05).

[0124] nd, not detected.

[0125] Example 15 Analysis of structural characteristics of Example 5 and Comparative Examples 3-4

[0126] Based on Examples 11-14, the hydrogen nuclear magnetic resonance spectra of the samples of Example 5 and Comparative Examples 3-4 were analyzed ( Figure 5 ), long-range crystal ordered structure ( Figure 6 ), short-range molecular order ( Figure 7 ) and thermodynamic properties ( Figure 8 and Table 3). Figure 5 As shown, the resonance peaks of -CH3 and -CH2- representing the ends of the saturated chains of triglycerides appeared at 0.86 and 1.26-1.60 ppm in the nuclear magnetic peaks of Example 5, respectively, indicating that OSA starch interacted with coconut oil and successfully prepared an OSA starch-coconut oil binary complex, while the natural starch in Comparative Example 3 could not interact with coconut oil. The XRD spectrum of Example 5 shows the typical characteristic peaks of the V-type crystal structure of the complex (12.8 and 19.8°), and the crystallinity is 24.4% (Table 3), indicating that OSA starch and coconut oil formed a complex with a good V-type crystal structure. Subsequently, the complex interaction of OSA starch and coconut oil was further demonstrated by FITR spectroscopy. As Figure 7 As shown, Example 5 at 1734 cm -1 and 2857cm -1 The absorption peaks representing the carboxyl peak and CH asymmetric stretching vibration of methylene in triglycerides appeared, indicating that OSA starch interacted with coconut oil. Compared with Comparative Example 3 (0.43), Example 5 had a peak at 1047 / 1022 cm -1 The infrared absorbance ratio at 0.68 indicates that it has strong short-range molecular order. Figure 8 Table 3 shows the thermodynamic curves of Example 5 and Comparative Example 3. p is 100.8℃, which forms V Ⅰb The crystalline structure of amylose-oil complex has an enthalpy of 6.5 J / g.

[0127] Table 3 Relative crystallinity, infrared absorbance ratio and thermodynamic properties of Example 5 and Comparative Example 3

[0128]

[0129] Note: Data are presented as mean ± SD. nd, not detected.

[0130] Example 16 In vitro digestion curves of Example 5 and Comparative Example 3

[0131] The in vitro digestibility test method for the starch-oil novel composite resistant starch food for special medical use is as follows:

[0132] 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:

[0133]

[0134] 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).

[0135] The in vitro digestion curves of Example 5 and Comparative Example 3 are as follows: Figure 9 As shown in the figure, the final digestion degree of Example 5 was approximately 53.3%, compared to the final digestion degree of Comparative Example 3 (-73.6%). This is attributed to the fact that the starch-coconut oil complex formed by OSA starch and coconut oil has a stable V-type crystal structure, and the introduction of the OS-group increases steric hindrance, thereby hindering the contact of amylase with the starch chain binding site, thereby reducing starch digestibility.

[0136] 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.

[0137] 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. An OSA starch-oil composite resistant starch, characterized in that The fat is selected from edible oil and triglyceride.

2. The OSA starch-oil composite resistant starch according to claim 1, characterized in that The oil is selected from: one or more of coconut oil and trilaurin.

3. The OSA starch-oil composite resistant starch according to claim 1, wherein the XRD characteristic diffraction peaks are located at 12.8° and 19.8°, and the relative crystallinity is 15.8-22.3%.

4. The OSA starch-oil composite resistant starch according to claim 1, wherein the IR characteristics are: Its short-range molecular ordered structure is at 1047 / 1022cm -1 The infrared absorbance ratio at 480 cm is 0.67 to 0.

76. -1 The half-peak width at 17.34~15.

08.

5. The OSA starch-oil composite resistant starch according to claim 1, characterized in that The degree of substitution of OS groups in OSA starch is between 0.010 and 0.

040.

6. The OSA starch-oil composite resistant starch according to claim 1, characterized in that The degree of substitution of OS groups in OSA starch is between 0.0150 and 0.

035.

7. The OSA starch-oil composite resistant starch according to claim 6, characterized in that The degree of OS group substitution in OSA starch ranges from 0.0161 to 0.0318.

8. The OSA starch-oil composite resistant starch according to claim 1, characterized in that The mass ratio of OSA starch to trilaurin is 1:0.01 to 0.

10.

9. The OSA starch-oil composite resistant starch according to claim 8, characterized in that The mass ratio of OSA starch to trilaurin is 1:0.04-0.

08.

10. A method for preparing the OSA starch-oil composite resistant starch according to any one of claims 1 to 9, characterized in that: (1) Adding oil to starch suspension, and thoroughly mixing starch and oil by ultrasonic combined with magnetic stirring; (2) heating the mixed starch-oil suspension in a water bath, controlling the temperature and reacting with magnetic stirring for 2 h; (3) The starch-oil reaction system is subjected to a gradient cooling treatment, and the uncomplexed oil in the starch paste is washed with anhydrous ethanol precipitation, freeze-dried, and ground to obtain starch-oil ester composite resistant starch.

11. The preparation method according to claim 10, characterized in that: In the step (1), OSA starch is dispersed in the aqueous phase to form a suspension with a concentration of 5% to 8%.

12. The preparation method according to claim 10, characterized in that In the step (1), the ultrasonic power range is 100-300 W, the ultrasonic treatment interval time is 4-12 s / min (ultrasonic time / stirring time), the magnetic stirring is 300-600 rpm, and the stirring time is 5 min.

13. The preparation method according to claim 10, characterized in that In step (2), the reaction system is heated to 90° C. at a rate of 5° C. / min, the internal temperature of the system is maintained at 90±1° C., and the magnetic stirring speed is 1000-1500 rpm.

14. The preparation method according to claim 10, characterized in that In the step (3), the magnetic stirring rate is 100-150 rpm, and in the cooling and compounding stage, the starch paste is gradually cooled from 90° C. to 20° C. within 4 hours. After the starch paste is treated with anhydrous ethanol in a volume ratio of 1:2 to 5, the supernatant is removed, the paste is quick-frozen in liquid nitrogen for 5 minutes, and then freeze-dried at -80° C. and ground through a 100-mesh sieve.

15. The preparation method according to claim 10, characterized in that In step (3), the gradient cooling is divided into 4 steps: cooling from 90°C to 75°C within 0-0.5h; cooling from 75°C to 50°C within 0.5-1h; cooling from 50°C to 30°C within 1-3h; cooling from 30°C to 20°C within 3-4h.

16. Use of the OSA starch-oil composite resistant starch according to any one of claims 1 to 9 in the preparation of food, food for special medical use, and functional food.

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