The Effect Of Starch Debranching On Its Molecules Self-Assembling Behavious And Its Applications

In this paper, we used debranching enzyme to debranch the gelatinized waxy maize starch. After the resurrection with different conditions, crystals of different forms and characteristics was produced, whose structure was analyzed to study the recrystallization process of molecular self-assembly behavior. Results are as follows:With different debranching treatment time, starch hydrolysis presented different molecular distribution. The longer debranching time, the higher content of small molecular weight components in enzymatic liquid medium. And with the extension of debranching time, the viscosity of the starch paste systems exhibited different degrees of decline. Enzyme solution debranched for 2h had a porous structure and the highest yield (82.19%) after crystallization at room temperature. Its morphological characteristics were significantly distinct of that which are debranched for 12h and 24h, whose crystals formed spherical microcrystalline structure. Infrared analysis found that extension of debranching time helped to improve the structure factor index, showing that molecules are highly ordered. X-ray diffraction test found that starch recrystallization crystals debranched for 2h, 12h and 24h showed a B-type structure, and reflected the highest degree of crystallinity (12.79%) when the debranching time was fixed at 24h.As the recrystallization temperature increased, the yield of starch crystallization debranched with different time showed a downward trend. The morphology of starch recrystallized crystals was influenced differently by different temperature. For samples debranched for 24h, with the temperature increased, the morphology of starch microspheres was broken, and the size of the particle decreased. The particle size distribution of crystal debranched for 2h were concentrated in 6.505-7.241μm and 13.76-18.97μm without much difference in the crystal with different temperature. X-ray diffraction pattern shows that when debranching time reached 24h, the structure of crystals in enzymatic liquid at higher temperature (50℃) could be converted to A-type. When the temperature increased, the starch crystal structure factor index increased, indicating the enhancement of internal ordering, which resulted in starch crystals formed at higher temperature had a greater resistance to enzymatic digestion.From the result of complexation reaction of polyphenols and starch, we found that the yield of the complexes debranched for 12h was the biggest, and sample debranched for 24h had the highest proportion of polyphenols in complexes. SEM showed that polyphenols had influenced the morphology of starch crystal debranched for 2h at the maximum extent. IR spectrum analysis showed that polyphenols had different effects on the rearrangement of assembly behavior of debranched starch, which led to the change of internal molecular ordering.