Preparation And Physicochemical Characterization On Solid Complex Of Starches With Rutin And Quercetin

Study on preparation and physicochemical characterization on solid complex of starches with rutin and quercetin, we chose porous starch and pregelatinized starch as the solid support, respectively.During the production process of porous starch,oil absorption ratio of porous starch and degree of the corn starch hydrolysised were use as the index to evaluate the porous starch. Based on single factors and orthogonal experiment designed, optional conditions of porous starch production were obtained:the ratio of alpha-amylase and glucoamylase is1:6; quantity of complex enzymes added could theoretically hydrolyze50%of raw starch; reaction temperature is55℃; soluble solid concentration is40%(w/v); pH is5.5and the reaction time is32h. The oil absorption of porous corn starch is59.62%under this condition. Porous starch was used to absorb rutin and quercetin, the maximum adsorption capacity of rutin is5.32mg/g; the maximum adsorption capacity of quercetin is7.94mg/g.Prepared the sharch with different content of rutin and quercetin by solvent dispersing method and freeze-drying. Rutin-starch samples have good solubility and swelling power at different temperatures. The solubility was enhanced with the increaseing of rutin, when the swelling power tapered off. Starches with different percentage of rutin were prepared and their formation was confirmed by the presence of the carbonyl signal around1662cm-1in the FT-IR spectra. Scanning electron microscopy (SEM) suggested most of the starch granules disintegrated with many visible fragments along with increasing rutin content in the binary mixtures. X-ray diffraction of rutin-starch complexes revealed that new crystalline regions were formed with the increasing of rutin. The thermal behavior of rutin-starch was investigated using TG/DTA and DSC. It was observed that the mass loss and thermal stability of complexes less depend on the contents of rutin. There were no obvious differences between pregelatinized starch and rutin-starch complexes in digestion rate.Quercetin-starch samples have good solubility and swelling power at different temperatures. The solubility was enhanced with the increaseing of quercetin, when the swelling power tapered off. Starches with different content of quercetin were prepared and their formation was confirmed by the presence of the carbonyl signal around1662cm-1in the FT-IR spectra. SEM suggested most of the starch granules disintegrated with many visible fragments along with increasing quercetin content in the binary mixtures. X-ray of quercetin-starch complexes revealed that the crystal structure of native starch was disappeared and new crystalline regions were formed. The thermal behavior of quercetin-starch was investigated using thermogravimetric analyses and differential scanning calorimetry. It was observed that the mass loss and thermal stability of complexes depend on the content of quercetin in the complexes. There were obvious differences between pregelatinized starch and quercetin-starch complexes in digestion rate. The digestion rate was drastically reduced as the quercetin was blended. The digestion rate was steady at about37.3%for pregelatinized starch and10.1%for quercetin-starch (with2.5%quercetin) after incubating2hours. The residual starch of quercetin-starch complexes can be thought as resistant starch, the amounts of resistant starch were sharply increased in comparison with the pregelatinized starch.