Starch

as a natural polymer

has unique microstructures and complex processing properties

which involves multiple physical and chemical reactions

i.e.water diffusion

granule expansion

gelatinization

melting

decomposition

recrystallization

etc.In this paper an attempt has been made to review the current state of knowledge and development on the microstructures and the phase transitions of starch under shear and shearless conditions.It reviews both fundamental science such as microstructures

phase transitions (especially for gelatinization

retrogradation and thermal stability) and rheological properties of different kinds of starches

and various processing techniques which have specific influneces on the phase changes.This paper also covers the general principles

capabilities

advantages and limitations of various techniques and methods available to study microstructures and phases transitions of starch.Based on the knowledge that have received widespread acceptance and those are still under debate

this comprehensive review aims at distinguishing the relationship between the microstructure and phase transitions.In particular

using corn starch with different ratios of amylose/amylopectin as model material

which provide a better understanding of the phase transitions and microstructure of starches

to develop the approach for product design and processing control of thermal procession of starch

and starch modification.The achievements in this area have increased our knowledge of polymer science

in particular that of natural polymers.