Establishment Of Amylose Flavonoid Compound System In Tartary Buckwheat And Study On Its Digestion Kinetics Model

Tartary buckwheat belongs to Polygonaceae Fagopyrum pseudograss plant.It is a kind of food and medicine homologous food crop rich in flavonoids such as rutin and quercetin.Its outstanding antioxidant,hypoglycemic,the health-care functions such as lowering blood lipids have attracted wide attention from researchers at home and abroad.Studies have shown that the interaction between Tartary buckwheat starch and flavonoids during processing will affect the physical and chemical properties and functional properties of Tartary buckwheat products,but the mechanism of its effect is still unclear.In this paper,alkaline extraction combined with pullulanase is used to treat Tartary buckwheat flour,and modern analysis methods such as scanning electron microscope,X-ray diffraction analyzer,Fourier infrared spectroscopy are used to construct the gelatinization treatment,ultrasonic treatment and ultra-high pressure treatment under different conditions.The physical and chemical properties and structural properties of the Tartary buckwheat amylose flavonoid complex system(HBS-BF)have been studied carefully.The in vitro simulation system was further established,and the Ritger-Peppas equation and the first-order kinetic equation were used to reveal the release law of flavonoids in the composite system.The main findings are as follows:(1)The composite degree results show that the ultra-high pressure treatment can significantly increase the composite degree of starch and flavonoids in the composite.Compared with the composite degree of starch and flavonoids in natural Tartary buckwheat(3.31%),the composite after HHP600-4 is composited.Degree increased to 53.16%.The particle size results of the composite show that,compared with the thermal gelatinization treatment,the ultrasonic treatment and the ultra-high pressure treatment reduce the particle size of the composite,and the particle size distribution range of the composite after the ultra-high pressure treatment is more concentrated.The transparency results show that with the increase of the standing time,the rate of decrease in transparency will increase,but the composite system after ultra-high pressure treatment has a high degree of compounding,and the decrease in transparency tends to be smaller.The study of solubility and swelling potential showed that the solubility of the compound increased with the increase of temperature.Compared with the gelatinization treatment group,the ultra-high pressure treatment significantly reduced the solubility of the compound,but had little effect on its swelling potential.The freeze-thaw stability results show that ultra-high pressure treatment can reduce the water separation rate of the compound during the freezing process,thereby prolonging the shelf life of starchy foods.(2)The research results of the HBS-BF structure after different treatment methods show that gelatinization,ultrasonic treatment and 600 MPa ultra-high pressure treatment will cause the surface of the Tartary buckwheat amylose flavonoid complex to become rough,and there are many and small appearances.Hollow,and the surface of the composite after 400 MPa ultra-high pressure treatment is smooth and still maintains the ellipsoidal shape of natural Tartary buckwheat starch.Thermal characteristics studies have shown that ultra-high pressure treatment can improve the thermal stability and gelatinization enthalpy of the composite,which may be due to the fact that the flavonoids increase the interaction force between the Tartary buckwheat amylose chain and the chain.The X-ray diffraction results show that the complex after ultra-high pressure treatment is A-type crystal,which is consistent with natural Tartary buckwheat starch,while the complex crystal form after gelatinization and ultrasonic treatment becomes V-type.And the crystallinity of the composite after ultra-high pressure treatment increased significantly.The results of Fourier infrared spectroscopy showed that compared with the gelatinization and ultrasonic treatment groups,the ultra-high pressure treatment compound had a wider absorption peak between 3000 cm^-1 and 3500 cm^-1,and1047 cm^-1/1022 cm^-1 The value of becomes larger,indicating that there are more hydrogen bonds and a higher degree of order in the composite system after ultra-high pressure treatment.However,in general,no new covalent bonds have been produced,which indicates that the binding mode between Tartary buckwheat amylose and flavonoids is non-covalent bonds such as hydrogen bonds and hydrophobic forces.(3)Further,the Ritger-Peppas equation and the first-order kinetic equation are used to analyze the release law of flavonoids in HBS-BF under different processing conditions.The results show that:in the three environments of simulated human oral cavity,gastric juice and intestinal juice,the flavonoids are at different times After fitting the Ritger-Peppas equation,R² is greater than 0.96,and the fitting degree is good;according to the release parameter n,the release law of the compound in different simulated environments is classified,and the simulated oral cavity and simulated intestinal juice are processed under different conditions.The difference in the release of the compound after the treatment is relatively small,and the main influencing factors are the difference in the concentration of flavonoids(simulated oral cavity)and the degradation rate of surface starch(simulated intestinal juice).In the simulated gastric juice,the compound after gelatinization treatment has a higher performance.The high flavonoid release(62.35%)and the release parameter n>0.85 indicate that the degradation rate of the starch surface layer is the main factor affecting the release of flavonoids.The complex after ultra-high pressure treatment showed a lower flavonoid release(25.26%?32.16%),the release parameter n is between 0.43 and 0.85,indicating that the release law of flavonoids at this time is dependent on both its own concentration difference and the degradation rate of surface starch.After the first-order kinetic equation is fitted,R² is all>0.97,and the fit is good.In the simulated oral cavity,the maximum release of flavonoids is 5.36%,and the maximum release of flavonoids after gelatinization in gastric juice is 62.35%,The maximum release amount of the compound after ultra-high pressure treatment in the simulated gastric juice was 32.16%,which confirmed the conclusion of the Ritger-Peppas equation.Studies on the digestibility of the compound under different treatment conditions show that the compound after ultra-high pressure treatment has a higher digestibility resistance,which is directly proportional to the compound degree of Tartary buckwheat amylose flavonoids.The compound after treatment at 600 MPa for 4 times has the highest The resistant starch(RS)content of the sulphate is 41.26%,which is 21.06%higher than that of the gelatinized compound.In summary,the ultra-high pressure technology is a method that can increase the degree of binding between Tartary buckwheat starch and flavonoids,and is also a new method for preparing resistant starch.